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Each year, the world produces 300 million tons of plastic, much of which resists degradation and ends up polluting every corner of the globe. But a team of European scientists may have found a unique solution to the plastic problem. They discovered that a common insect can chew sizable holes in a plastic shopping bag within 40 minutes.

"This study is another milestone discovery for the research on biodegradation of plastics," says Wei-Min Wu, an environmental engineer at Stanford University.

The discovery was led by Federica Bertocchini, a developmental biologist at the University of Cantabria in Spain. She first noticed the possibility as she cleaned out her backyard bee hives two years ago.

She removed some wax worms ( Galleria mellonella) living in the hive and placed them in an old plastic bag. When she checked the bag an hour later, however, she discovered small holes in the part of the bag with the larvae. Although Bertocchini wasn't an entomologist, she guessed immediately what was happening.

The larval form of a small moth, wax worms get their names because they live on the wax in bee hives. Like plastic, wax is a polymer, which consists of a long string of carbon atoms held together, with other atoms branching off the sides of the chain. Both wax and the polyethylene in Bertocchini's plastic bag had a similar carbon backbone.

"Since they eat wax, they may have evolved a molecule to break it down, and that molecule might also work on plastic," Bertocchini said.

Bertocchini teamed up with fellow scientists Paolo Bombelli and Christopher Howe to figure out how the wax worms were pigging out on plastic.

When they placed the worms on polyethylene plastic, they found that each worm created an average of 2.2 holes per hour. Overnight, 100 wax worms degraded 92 milligrams of a plastic shopping bag. At this rate, it would take these same 100 worms nearly a month to completely break down an average, 5.5 gram plastic bag.

To rule out munching action from their jaws as the source of degradation, the team applied a soupy blend of recently deceased worms to the plastic and waited. Sure enough, they found the liquid larvae could also eat holes in plastic. This told Bertocchini and colleagues that an enzyme in the worms or the bacteria living in and on their bodies was dissolving the plastic.

That enzyme converted polyethylene into ethylene glycol, a chemical commonly used in antifreeze. Bertocchini hopes to identify the precise enzymes that break down polyethylene in future work.

Searching for a Solution

Scientists have searched for a way to biodegrade plastics for decades, says Uwe Bornscheuer, a biochemist at the University of Greifswald in Germany.

"Plastic pollution is a big global problem," Bornscheuer said.

In 2014, Wu and colleagues at Stanford University found that a gut bacterium in another species of wax worm could break down polyethylene, although it had different byproducts. A 2016 study identified the enzymes in a species of bacteria that could break down a type of plastic called poly(ethylene terephthalate).

"There are probably lots of other worm species out there that can degrade plastics," he said.

To marine biologist Tracy Mincer at the Woods Hole Oceanographic Institute, the solution to plastic pollution needs to focus on producing less and recycling more.

"Polyethylene is a high-quality resin that can be up-cycled in many ways and can fetch up to $500 per tonne," he said in an email. "In my opinion, although this is an amazing natural history story and wonderful academic exercise, it is not a solution for disposing of polyethylene as this is throwing away money."

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This Bug Can Eat Plastic. But Can It Clean Up Our Mess?

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Each year, the world produces 300 million tons of plastic, much of which resists degradation and ends up polluting every corner of the globe. But a team of European scientists may have found a unique solution to the plastic problem. They discovered that a common insect can chew sizable holes in a plastic shopping bag within 40 minutes.

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Car accidents, sports injuries, even too much typing and texting can injure the peripheral nerves, leaving people with numbness, tingling and weakness in their hands, arms or legs. Recovery can take months, and doctors have little to offer to speed it along.

Now, researchers at Washington University School of Medicine in St. Louis and Northwestern University have developed an implantable, biodegradable device that delivers regular pulses of electricity to damaged peripheral nerves in rats, helping the animals regrow nerves in their legs and recover their nerve function and muscle strength more quickly. The size of a quarter, the device lasts about two weeks before being completely absorbed into the body.

The findings are published Oct. 8 in Nature Medicine.

For most people with peripheral nerve injuries, doctors suggest painkillers such as aspirin and physical therapy. Severe cases may require surgery, and standard practice is to administer some electrical stimulation to the injured nerves during the surgery to aid recovery.

"We know that electrical stimulation during surgery helps, but once the surgery is over, the window for intervening is closed," said co-senior author Wilson "Zack" Ray, MD, an associate professor of neurosurgery, of biomedical engineering and of orthopedic surgery at Washington University. "With this device, we've shown that electrical stimulation given on a scheduled basis can further enhance nerve recovery."

Unlike neurons in the brain and spinal cord, the peripheral nerves that run through the arms, legs and torso can regenerate after injury. Electrical stimulation triggers the release of growth-promoting proteins, boosting nerve cells' natural abilities and helping them regrow faster and more completely.

But until now, doctors have lacked a means to continuously provide that added boost.

Co-senior author John Rogers, PhD, of Northwestern, and colleagues designed and developed a device that wraps around an injured nerve and delivers electrical pulses for days before the device harmlessly degrades in the body. The device is powered wirelessly by a transmitter outside the body that acts much like a cell phone charging mat.

"These platforms represent the first examples of a 'bioelectronic medicine' -- engineered systems that provide active, therapeutic function in a programmable, dosed format and then naturally disappear into the body, without a trace," Rogers said. "In the case reported here, we built bioresorbable electronic devices that support unique function relevant to recovery from damage to a peripheral nerve, via electrical stimulation at select time points during the healing process."

The researchers studied rats with injured sciatic nerves. This nerve sends signals up and down the legs and controls the hamstrings and muscles of the lower legs and feet. They used the device to provide one hour per day of electrical stimulation to the rats for one, three or six days, or no electrical stimulation at all, and then monitored their recovery for the next 10 weeks. Any electrical stimulation was better than none at all at helping the rats recover muscle mass and muscle strength. In addition, the more days of electrical stimulation the rats received, the more quickly and thoroughly they recovered nerve signaling and muscle strength.

"Before we did this study, we weren't sure that longer stimulation would make a difference, and now that we know it does we can start trying to find the ideal time frame to maximize recovery," Ray said. "Had we delivered electrical stimulation for 12 days instead of six, would there have been more therapeutic benefit? Maybe. We're looking into that now."

By varying the composition and thickness of the materials in the device, Rogers and colleagues can control the precise number of days it lasts before disintegrating. They are working now on creating new versions that can provide electrical pulses for weeks before degrading.

"There really are no therapeutic options for some of these nerve injury patients," Ray said. "This isn't a therapeutic option yet either, as it hasn't been tested in people. But I'm excited about it because it's a new approach to treating peripheral nerve injury, and it might offer a solution where really there is none today in the clinical realm."

Journal Reference:

Jahyun Koo, Matthew R. MacEwan, Seung-Kyun Kang, Sang Min Won, Manu Stephen, Paul Gamble, Zhaoqian Xie, Ying Yan, Yu-Yu Chen, Jiho Shin, Nathan Birenbaum, Sangjin Chung, Sung Bong Kim, Jawad Khalifeh, Daniel V. Harburg, Kelsey Bean, Michael Paskett, Jeonghyun Kim, Zohny S. Zohny, Seung Min Lee, Ruoyao Zhang, Kaijing Luo, Bowen Ji, Anthony Banks, Hyuck Mo Lee, Younggang Huang, Wilson Z. Ray, John A. Rogers. Wireless bioresorbable electronic system enables sustained nonpharmacological neuroregenerative therapy. Nature Medicine, 2018; DOI: 10.1038/s41591-018-0196-2

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neuropathy; nervous system; eye care; brain injury; depression; neuroscience; biology; life sciences; molecular biology

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Implantable, biodegradable devices speed nerve regeneration in rats: Pulses of electrical stimulation help heal injured nerves

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Car accidents, sports injuries, even too much typing and texting can injure the peripheral nerves, leaving people with numbness, tingling and weakness in their hands, arms or legs. Recovery can take months, and doctors have little to offer to speed it along. Now, researchers at Washington University School of Medicine in St.

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The northern eyewall of Hurricane Michael comes ashore between St. Vincent Island and Panama City, Florida, on Oct. 10, 2018.

Credit: NOAA

Forecasters watching Hurricane Michael barrel toward the Gulf coast of Florida earlier this week saw the storm do something "most unusual."

The hurricane intensified despite encountering wind shear -a change in wind speed or direction at different levels in the atmosphere-that might have normally weakened the storm.

"Michael's steady intensification over the past 48 hours in the face of 20-knot [23 mph] westerly shear defies traditional logic," hurricane specialist Stacy Stewart wrote in a memo from the National Hurricane Center on Monday (Oct. 8). "Either the shear calculations are unrepresentative or Michael has become more inertially stable due to its large eye and large outer wind field, making it more shear-resistant."

So how would forecasters typically expect wind shear to affect a storm? That's explained in part by the shape of a hurricane. [ Hurricane Season 2018: How Long It Lasts and What to Expect]

Other non-hurricane storm systems, such as Nor'easters that hit the mid-Atlantic, are driven by differences in temperature and take on a sloped shape in the atmosphere. The warmest parts of the storm closest to Earth's surface are usually out at the front of the system with the highest part trailing back usually to the west and northwest to where the cold air is.

Hurricanes, meanwhile, stretch from Earth's surface to the upper reaches of the atmosphere and each level of the storm needs to be stacked and working in coordination to help the massive system gain energy and grow in intensity.

"With a hurricane you can see the eye from outer space; it's more like a chimney," Joel Cline, Tropical Program Coordinator at NOAA's National Weather Service, told Live Science. "If the chimney's not perfectly straight, you can have the hottest fire -in other words, the warmest water -but the flame goes out."(Warm water fuels hurricanes.)

Wind shear could disrupt the hurricane, essentially tilting or breaking up the chimney, which would weaken the storm. But that didn't happen in Hurricane Michael's case.

"There was some available wind shear when it was near Cuba right before it went into the Gulf, and wind shear is one of the variables that will decrease the intensity of a storm," Marangelly Fuentes, a NASA atmospheric scientist, told Live Science. But the storm really intensified, going from a Category 1 to a Category 4 hurricane in a matter of 24 hours, once it went into the Gulf.

"You have to remember that Michael actually intensified to a Category 4 -almost 5 right now -after it was in the Gulf of Mexico where there was not that much shear," Fuentes said.

A lack of shear was just one of the factors that caused Michael to intensify, Fuentes explained. Sea-surface temperatures are warmer than average in the Gulf of Mexico right now, adding more fuel to the storm. A lack of friction from land also allowed Michael to keep gaining strength over the water.

The huge storm strengthened to a Category 4 hurricane overnight, packing winds up to 145 mph (230 km/h) as it approached the Florida Panhandle this morning.

"People get very fixated on the category numbers-it doesn'tmatter at this point," Kline said. In addition to the potentially deadly storm surge expected to hit parts of the Florida coast, the wind damage will be extensive near the eye of the storm, Kline said, and rainfall is a big concern, especially in areas that were lashed by Florence last month. "Because of what's happened [with Florence] in the recent past, there's a greater chance of flash floods."

And while a Category 4 storm might be unprecedented for the Florida Panhandle, Kline noted that major hurricanes are predicted to strike this part of the Florida coast about every 30 years, as a National Hurricane Center map shows.

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Why Did Hurricane Michael Become Such a Monster Storm So Quickly?

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Forecasters watching Hurricane Michael barrel toward the Gulf coast of Florida earlier this week saw the storm do something "most unusual." The hurricane intensified despite encountering wind shear -a change in wind speed or direction at different levels in the atmosphere-that might have normally weakened the storm.

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The Big Bang Theory explains how the universe began with an infinitely hot and dense single point that inflated to form the ever-expanding cosmos we see today.

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Astronomers from Lund University in Sweden have now found the explanation to a recent mystery at the centre of the Milky Way galaxy: the high levels of scandium discovered last spring near the galaxy's giant black hole were in fact an optical illusion.

Last spring, researchers published a study about the apparent presence of astonishing and dramatically high levels of three different elements in red giant stars, located less than three light years away from the big black hole at the centre of our galaxy. Various possible explanations were presented, for example that the high levels were a result of earlier stars being disrupted as they fall into the black hole, or a result of debris from the collisions of neutron stars.

Now another group of astronomers from Lund University among others, in collaboration with UCLA in California, have found an explanation for the high levels of scandium, vanadium and yttrium. They argue that the so-called spectral lines presented last spring were actually an optical illusion. Spectral lines are used to find out which elements a star contains -- by using its own light.

"These giant red stars have used up most of their hydrogen fuel and their temperatures are therefore only half of the sun's," says Brian Thorsbro, lead author of the study and doctoral student in astronomy at Lund University.

According to the new study, the lower temperatures of the giant stars helped to create the optical illusion that appeared in the measurements of spectral lines. Specifically, it means that the electrons in the elements behave differently at different temperatures, which in turn can be misleading when measuring the spectral lines of elements in different stars. The conclusion is the result of a close collaboration between astronomers and atomic physicists.

Brian Thorsbro and his colleagues have had the world's largest telescope, at the W. M. Keck Observatory on Mauna Kea, Hawaii, at their disposal, thanks to their collaboration with R. Michael Rich at UCLA. Using this telescope and others, the research team is currently conducting a comprehensive mapping of the central areas of the Milky Way, exploring the spectral lines in the light from different stars to find out which elements they contain. The purpose is to gain an understanding of the events that have occurred in the history of the Milky Way, but also to understand how galaxies in general have formed.

"Our research collaboration is world-leading in terms of systematically mapping the elements contained in the huge central star cluster -- the star cluster that surrounds the black hole," says research leader and astronomer Nils Ryde at Lund University.

The spectral lines for different elements are recorded in a high-resolution spectrometer -- an advanced camera that generates a rainbow of the starlight. The research team has studied the part of the spectrum consisting of near-infrared light, i.e. the heat radiation emitted by the stars. The reason for this is that infrared light can penetrate the dust that obstructs the line-of-sight between us and the centre of the Milky Way, approximately 25,000 light years away. The technology for recording this light is very advanced, and has only recently become available to astronomers.

"We have only started to map the stellar compositions in these central areas of the Milky Way," says Nils Ryde.

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stars; galaxies; astronomy; black holes; astrophysics; cosmology; space telescopes; extrasolar planets

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Mystery at the center of the Milky Way solved

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Astronomers from Lund University in Sweden have now found the explanation to a recent mystery at the centre of the Milky Way galaxy: the high levels of scandium discovered last spring near the galaxy's giant black hole were in fact an optical illusion.

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A global shift towards healthy and more plant-based diets, halving food loss and waste, and improving farming practices and technologies are required to feed 10 billion people sustainably by 2050, a new study finds. Adopting these options reduces the risk of crossing global environmental limits related to climate change, the use of agricultural land, the extraction of freshwater resources, and the pollution of ecosystems through overapplication of fertilizers, according to the researchers.

The study, published in the journal Nature, is the first to quantify how food production and consumption affects the planetary boundaries that describe a safe operating space for humanity beyond which Earth's vital systems could become unstable.

"No single solution is enough to avoid crossing planetary boundaries. But when the solutions are implemented together, our research indicates that it may be possible to feed the growing population sustainably," says Dr Marco Springmann of the Oxford Martin Programme on the Future of Food and the Nuffield Department of Population Health at the University of Oxford, who led the study.

"Without concerted action, we found that the environmental impacts of the food system could increase by 50-90% by 2050 as a result of population growth and the rise of diets high in fats, sugars and meat. In that case, all planetary boundaries related to food production would be surpassed, some of them by more than twofold."

The study, funded by EAT as part of the EAT-Lancet Commission for Food, Planet and Health and by Wellcome's "Our Planet, Our Health" partnership on Livestock Environment and People, combined detailed environmental accounts with a model of the global food system that tracks the production and consumption of food across the world. With this model, the researchers analysed several options that could keep the food system within environmental limits. They found:

Climate change cannot be sufficiently mitigated without dietary changes towards more plant-based diets. Adopting more plant-based "flexitarian" diets globally could reduce greenhouse gas emissions by more than half, and also reduce other environmental impacts, such as fertilizer application and the use of cropland and freshwater, by a tenth to a quarter.

In addition to dietary changes, improving management practices and technologies in agriculture is required to limit pressures on agricultural land, freshwater extraction, and fertilizer use. Increasing agricultural yields from existing cropland, balancing application and recycling of fertilizers, and improving water management, could, along with other measures, reduce those impacts by around half.

Finally, halving food loss and waste is needed for keeping the food system within environmental limits. Halving food loss and waste could, if globally achieved, reduce environmental impacts by up to a sixth (16%).

"Many of the solutions we analysed are being implemented in some parts of the world, but it will need strong global co-ordination and rapid upscale to make their effects felt," says Springmann.

"Improving farming technologies and management practices will require increasing investment in research and public infrastructure, the right incentive schemes for farmers, including support mechanisms to adopt best available practices, and better regulation, for example of fertilizer use and water quality," says Line Gordon, executive director of the Stockholm Resilience Centre and an author on the report.

Fabrice de Clerck, director of science at EAT says, "Tackling food loss and waste will require measures across the entire food chain, from storage, and transport, over food packaging and labelling to changes in legislation and business behaviour that promote zero-waste supply chains."

"When it comes to diets, comprehensive policy and business approaches are essential to make dietary changes towards healthy and more plant-based diets possible and attractive for a large number of people. Important aspects include school and workplace programmes, economic incentives and labelling, and aligning national dietary guidelines with the current scientific evidence on healthy eating and the environmental impacts of our diet," adds Springmann.

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agriculture and food; food and agriculture; food; nature; environmental issues; environmental policy; ecology; environmental awareness

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Feeding 10 billion people by 2050 within planetary limits may be achievable

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A new study quantifies how food production and consumption affects the planetary boundaries that describe a safe operating space for humanity beyond which Earth's vital systems could become unstable.

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jeremy roos

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People have always taken space for granted. It is just emptiness, after all-a backdrop to everything else. Time, likewise, simply ticks on incessantly. But if physicists have learned anything from the long slog to unify their theories, it is that space and time form a system of such staggering complexity that it may defy our most ardent efforts to understand.

Albert Einstein saw what was coming as early as November 1916. A year earlier he had formulated his general theory of relativity, which postulates that gravity is not a force that propagates through space but a feature of spacetime itself. When you throw a ball high into the air, it arcs back to the ground because Earth distorts the spacetime around it, so that the paths of the ball and the ground intersect again. In a letter to a friend, Einstein contemplated the challenge of merging general relativity with his other brainchild, the nascent theory of quantum mechanics. That would not merely distort space but dismantle it. Mathematically, he hardly knew where to begin. "How much have I already plagued myself in this way!" he wrote.

Einstein never got very far. Even today there are almost as many contending ideas for a quantum theory of gravity as scientists working on the topic. The disputes obscure an important truth: the competing approaches all say space is derived from something deeper-an idea that breaks with 2,500 years of scientific and philosophical understanding.

Down the Black Hole

A kitchen magnet neatly demonstrates the problem that physicists face. It can grip a paper clip against the gravity of the entire Earth. Gravity is weaker than magnetism or than electric or nuclear forces. Whatever quantum effects it has are weaker still. The only tangible evidence that these processes occur at all is the mottled pattern of matter in the very early universe-thought to be caused, in part, by quantum fluctuations of the gravitational field.

Black holes are the best test case for quantum gravity. "It's the closest thing we have to experiments," says Ted Jacobson of the University of Maryland, College Park. He and other theorists study black holes as theoretical fulcrums. What happens when you take equations that work perfectly well under laboratory conditions and extrapolate them to the most extreme conceivable situation? Will some subtle flaw manifest itself?

General relativity predicts that matter falling into a black hole becomes compressed without limit as it approaches the center-a mathematical cul-de-sac called a singularity. Theorists cannot extrapolate the trajectory of an object beyond the singularity; its time line ends there. Even to speak of "there" is problematic because the very spacetime that would define the location of the singularity ceases to exist. Researchers hope that quantum theory could focus a microscope on that point and track what becomes of the material that falls in.

Out at the boundary of the hole, matter is not so compressed, gravity is weaker and, by all rights, the known laws of physics should still hold. Thus, it is all the more perplexing that they do not. The black hole is demarcated by an event horizon, a point of no return: matter that falls in cannot get back out. The descent is irreversible. That is a problem because all known laws of fundamental physics, including those of quantum mechanics as generally understood, are reversible. At least in principle, you should be able to reverse the motion of all the particles and recover what you had.

A very similar conundrum confronted physicists in the late 1800s, when they contemplated the mathematics of a "black body," idealized as a cavity full of electromagnetic radiation. James Clerk Maxwell's theory of electromagnetism predicted that such an object would absorb all the radiation that impinges on it and that it could never come to equilibrium with surrounding matter. "It would absorb an infinite amount of heat from a reservoir maintained at a fixed temperature," explains Rafael Sorkin of the Perimeter Institute for Theoretical Physics in Ontario. In thermal terms, it would effectively have a temperature of absolute zero. This conclusion contradicted observations of real-life black bodies (such as an oven). Following up on work by Max Planck, Einstein showed that a black body can reach thermal equilibrium if radiative energy comes in discrete units, or quanta.

Theoretical physicists have been trying for nearly half a century to achieve an equivalent resolution for black holes. The late Stephen Hawking of the University of Cambridge took a huge step in the mid-1970s, when he applied quantum theory to the radiation field around black holes and showed they have a nonzero temperature. As such, they can not only absorb but also emit energy. Although his analysis brought black holes within the fold of thermodynamics, it deepened the problem of irreversibility. The outgoing radiation emerges from just outside the boundary of the hole and carries no information about the interior. It is random heat energy. If you reversed the process and fed the energy back in, the stuff that had fallen in would not pop out; you would just get more heat. And you cannot imagine that the original stuff is still there, merely trapped inside the hole, because as the hole emits radiation, it shrinks and, according to Hawking's analysis, ultimately disappears.

This problem is called the information paradox because the black hole destroys the information about the infalling particles that would let you rewind their motion. If black hole physics really is reversible, something must carry information back out, and our conception of spacetime may need to change to allow for that.

Atoms of Spacetime

Heat is the random motion of microscopic parts, such as the molecules of a gas. Because black holes can warm up and cool down, it stands to reason that they have parts-or, more generally, a microscopic structure. And because a black hole is just empty space (according to general relativity, infalling matter passes through the horizon but cannot linger), the parts of the black hole must be the parts of space itself. As plain as an expanse of empty space may look, it has enormous latent complexity.

Even theories that set out to preserve a conventional notion of spacetime end up concluding that something lurks behind the featureless facade. For instance, in the late 1970s Steven Weinberg, now at the University of Texas at Austin, sought to describe gravity in much the same way as the other forces of nature. He still found that spacetime is radically modified on its finest scales.

Physicists initially visualized microscopic space as a mosaic of little chunks of space. If you zoomed in to the Planck scale, an almost inconceivably small size of 10 ⁻³⁵ meter, they thought you would see something like a chessboard. But that cannot be quite right. For one thing, the grid lines of a chessboard space would privilege some directions over others, creating asymmetries that contradict the special theory of relativity. For example, light of different colors might travel at different speeds-just as in a glass prism, which refracts light into its constituent colors. Whereas effects on small scales are usually hard to see, violations of relativity would actually be fairly obvious.

The thermodynamics of black holes casts further doubt on picturing space as a simple mosaic. By measuring the thermal behavior of any system, you can count its parts, at least in principle. Dump in energy and watch the thermometer. If it shoots up, that energy must be spread out over comparatively few molecules. In effect, you are measuring the entropy of the system, which represents its microscopic complexity.

If you go through this exercise for an ordinary substance, the number of molecules increases with the volume of material. That is as it should be: If you increase the radius of a beach ball by a factor of 10, you will have 1,000 times as many molecules inside it. But if you increase the radius of a black hole by a factor of 10, the inferred number of molecules goes up by only a factor of 100. The number of "molecules" that it is made up of must be proportional not to its volume but to its surface area. The black hole may look three-dimensional, but it behaves as if it were two-dimensional.

This weird effect goes under the name of the holographic principle because it is reminiscent of a hologram, which presents itself to us as a three-dimensional object. On closer examination, however, it turns out to be an image produced by a two-dimensional sheet of film. If the holographic principle counts the microscopic constituents of space and its contents-as physicists widely, though not universally, accept-it must take more to build space than splicing together little pieces of it.

The relation of part to whole is seldom so straightforward, anyway. An H ₂O molecule is not just a little piece of water. Consider what liquid water does: it flows, forms droplets, carries ripples and waves, and freezes and boils. An individual H ₂ O molecule does none of that: those are collective behaviors. Likewise, the building blocks of space need not be spatial. "The atoms of space are not the smallest portions of space," says Daniele Oriti of the Max Planck Institute for Gravitational Physics in Potsdam, Germany. "They are the constituents of space. The geometric properties of space are new, collective, approximate properties of a system made of many such atoms."

What exactly those building blocks are depends on the theory. In loop quantum gravity, they are quanta of volume aggregated by applying quantum principles. In string theory, they are fields akin to those of electromagnetism that live on the surface traced out by a moving strand or loop of energy-the namesake string. In M-theory, which is related to string theory and may underlie it, they are a special type of particle: a membrane shrunk to a point. In causal set theory, they are events related by a web of cause and effect. In the amplituhedron theory and some other approaches, there are no building blocks at all-at least not in any conventional sense.

Although the organizing principles of these theories vary, all strive to uphold some version of the so-called relationalism of 17th- and 18th-century German philosopher Gottfried Leibniz. In broad terms, relationalism holds that space arises from a certain pattern of correlations among objects. In this view, space is a jigsaw puzzle. You start with a big pile of pieces, see how they connect and place them accordingly. If two pieces have similar properties, such as color, they are likely to be nearby; if they differ strongly, you tentatively put them far apart. Physicists commonly express these relations as a network with a certain pattern of connectivity. The relations are dictated by quantum theory or other principles, and the spatial arrangement follows.

Phase transitions are another common theme. If space is assembled, it might be disassembled, too; then its building blocks could organize into something that looks nothing like space. "Just like you have different phases of matter, like ice, water and water vapor, the atoms of space can also reconfigure themselves in different phases," says Thanu Padmanabhan of the Inter-University Center for Astronomy and Astrophysics in India. In this view, black holes may be places where space melts. Known theories break down, but a more general theory would describe what happens in the new phase. Even when space reaches its end, physics carries on.

Entangled Webs

The big realization of recent years-and one that has crossed old disciplinary boundaries-is that the relevant relations involve quantum entanglement. An extrapowerful type of correlation, intrinsic to quantum mechanics, entanglement seems to be more primitive than space. For instance, an experimentalist might create two particles that fly off in opposing directions. If they are entangled, they remain coordinated no matter how far apart they may be.

Traditionally when people talked about "quantum" gravity, they were referring to quantum discreteness, quantum fluctuations and almost every other quantum effect in the book-but never quantum entanglement. That changed when black holes forced the issue. Over the lifetime of a black hole, entangled particles fall in, but after the hole evaporates fully, their partners on the outside are left entangled with-nothing. "Hawking should have called it the entanglement problem," says Samir Mathur of Ohio State University.

Even in a vacuum, with no particles around, the electromagnetic and other fields are internally entangled. If you measure a field at two different spots, your readings will jiggle in a random but coordinated way. And if you divide a region in two, the pieces will be correlated, with the degree of correlation depending on the only geometric quantity they have in common: the area of their interface. In 1995 Jacobson argued that entanglement provides a link between the presence of matter and the geometry of spacetime-which is to say, it might explain the law of gravity. "More entanglement implies weaker gravity-that is, stiffer spacetime," he says.

Several approaches to quantum gravity-most of all, string theory-now see entanglement as crucial. String theory applies the holographic principle not just to black holes but also to the universe at large, providing a recipe for how to create space-or at least some of it. For instance, a two-dimensional space could be threaded by fields that, when structured in the right way, generate an additional dimension of space. The original two-dimensional space would serve as the boundary of a more expansive realm, known as the bulk space. And entanglement is what knits the bulk space into a contiguous whole.

In 2009 Mark Van Raamsdonk of the University of British Columbia gave an elegant argument for this process. Suppose the fields at the boundary are not entangled-they form a pair of uncorrelated systems. They correspond to two separate universes, with no way to travel between them. When the systems become entangled, it is as if a tunnel, or wormhole, opens up between those universes, and a spaceship can go from one to the other. As the degree of entanglement increases, the wormhole shrinks in length, drawing the universes together until you would not even speak of them as two universes anymore. "The emergence of a big spacetime is directly tied into the entangling of these field theory degrees of freedom," Van Raamsdonk says. When we observe correlations in the electromagnetic and other fields, they are a residue of the entanglement that binds space together.

Many other features of space, besides its contiguity, may also reflect entanglement. Van Raamsdonk and Brian Swingle, now at the University of Maryland, College Park, argue that the ubiquity of entanglement explains the universality of gravity-that it affects all objects and cannot be screened out. As for black holes, Leonard Susskind of Stanford University and Juan Maldacena of the Institute for Advanced Study in Princeton, N.J., suggest that entanglement between a black hole and the radiation it has emitted creates a wormhole-a back-door entrance into the hole. That may help preserve information and ensure that black hole physics is reversible.

Whereas these string theory ideas work only for specific geometries and reconstruct only a single dimension of space, some researchers have sought to explain how all of space can emerge from scratch. For instance, ChunJun Cao, Spyridon Michalakis and Sean M. Carroll, all at the California Institute of Technology, begin with a minimalist quantum description of a system, formulated with no direct reference to spacetime or even to matter. If it has the right pattern of correlations, the system can be cleaved into component parts that can be identified as different regions of spacetime. In this model, the degree of entanglement defines a notion of spatial distance.

In physics and, more generally, in the natural sciences, space and time are the foundation of all theories. Yet we never see spacetime directly. Rather we infer its existence from our everyday experience. We assume that the most economical account of the phenomena we see is some mechanism that operates within spacetime. But the bottom-line lesson of quantum gravity is that not all phenomena neatly fit within spacetime. Physicists will need to find some new foundational structure, and when they do, they will have completed the revolution that began just more than a century ago with Einstein.

This article is part of a special report, "The Biggest Questions in Science," sponsored by The Kavli Prize. It was produced independently by Scientific American and Nature editors, who have sole responsibility for all the editorial content.

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People have always taken space for granted. It is just emptiness, after all-a backdrop to everything else. Time, likewise, simply ticks on incessantly. But if physicists have learned anything from the long slog to unify their theories, it is that space and time form a system of such staggering complexity that it may defy our most ardent efforts to understand.

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from research organizations

Is there a second Earth out there in space? Our knowledge of planetary systems far, far away is increasing constantly, as new technologies continue to sharpen our gaze into space. To date, 3,700 planets have already been discovered outside our solar system. The planetary masses and radii of these exoplanets can be used to infer their mean density, but not their exact chemical composition and structure. The intriguing question about what these planets could look like is thus still open.

"Theoretically, we can assume various compositions, such as a world of pure water, a world of pure rock, and planets that have hydrogen-helium atmospheres and explore what radii are expected" explains Michael Lozovsky, a doctoral candidate in the group of Prof. Ravit Helled at the Institute for Computational Science at the University of Zurich.
Thresholds for planetary composition
Lozovsky and collaborators have used databases and statistical tools to characterize exoplanets and their atmospheres. These are fairly common and surrounded by a volatile layer of hydrogen and helium. However, the directly measured data previously didn't allow the researchers to determine the exact structure, since different compositions may lead to the same mass and radius. In addition to the accuracy of the data relating to mass and radius, the research team thus also investigated the assumed internal structure, temperature and reflected radiation in 83 of the 3,700 known planets, for which the masses and radii are well-determined.

"We used a statistical analysis to set limits on possible compositions. Using a database of detected exoplanets, we found that every theoretical planetary structure has a 'threshold radius', a planetary radius above which no planets of this composition exist," explains Michael Lozovsky. The amount of elements in the gaseous layer that are heavier than helium, the percentage of hydrogen and helium, as well as the distribution of elements in the atmosphere are important factors in determining the threshold radius.
Super-Earths and mini-Neptunes
The researchers from the Institute for Computational Science found that planets with a radius of up to 1.4 times that of Earth (6,371 kilometers) can be earth-like, i.e. they have a composition similar to Earth. Planets with radii above this threshold have a higher share of silicates or other light materials. Most of the planets with a radius above 1.6 radii of the Earth must have a layer of hydrogen-helium gas or water in addition to their rocky core, while those larger than 2.6 Earth radii can't be water worlds and therefore might be surrounded by an atmosphere. Planets with radii larger than 4 Earth radii are expected to be very gaseous and consist of at least 10 percent hydrogen and helium, similarly to Uranus and Neptune.

The findings of the study provide new insights into the development and diversity of these planets. One particularly interesting threshold concerns the difference between large terrestrial-like planets -- otherwise known as super-Earths -- and small gaseous planets, also referred to as mini-Neptunes. According to the researchers, this threshold lies at a radius of three times that of Earth. Below this threshold, it is therefore possible to find earth-like planets in the vast expanse of the galaxy.

Journal Reference:

M. Lozovsky, R. Helled, C. Dorn, J. Venturini. Threshold Radii of Volatile-rich Planets. The Astrophysical Journal, 2018; 866 (1): 49 DOI: 10.3847/1538-4357/aadd09

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extrasolar planets; pluto; kuiper belt; asteroids

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comets and meteors; astrophysics; satellites; nebulae; solar system

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Researchers have analyzed the composition and structure of faraway exoplanets using statistical tools. Their analysis indicates whether a planet is earth-like, made up of pure rock or a water-world. The larger the planet, the more hydrogen and helium surround it.

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https://www.nasa.gov/audience/forstudents/k-4/stories/nasa-knows/what-is-a-black-hole-k4.html

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Multimedia Gallery - Zealandia on deck: a sediment core obtained through deep-sea drilling is pored over by scientists. | NSF - National Science Foundation

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NSF's mission is to advance the progress of science, a mission accomplished by funding proposals for research and education made by scientists, engineers, and educators from across the country.

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Credit: Vadim Sadovski/Shutterstock

The Earth's mantle acts like a giant churn, circulating cool oceanic crust downward toward the core, where it heats up into a goopy solid and then rises again - a process that powers everything from plate tectonics to volcanism.

But there are some hitches in this system, and new research reveals why: A slippery layer about 416 miles (670 kilometers) deep stops chunks of crust in their tracks, creating "stagnant slabs" in the middle of the mantle, the layer between the Earth's crust and its core. [ In Photos: Ocean Hidden Beneath Earth's Surface]

"This deflection of slabs was always puzzling to our understanding of [the mantle]," said Shijie Zhong, a physicist at the University of Colorado Boulder and the co-author of the new study published Oct. 1 in the journal Nature Geoscience.

There is no way to look directly at the mantle, but scientists study its dynamics using seismic waves from earthquakes. By detecting the waves as they propagate through the globe, researchers can construct a picture of the mantle, not unlike how radar can image objects using radio waves.

What happens in the mantle is related to what's going on in the crust. The crust is made up of tectonic plates that ride across the mantle like rafts on a very, very thick sea (the consistency of the crust is similar to that of hot asphalt). In some areas, called subduction zones, one tectonic plate dives under another, grinding chunks of oceanic crust down into the mantle. From seismology, Zhong said, researchers knew that some of these slabs of crust don't always travel the full 1,860 miles (3,000 km) to the core-mantle boundary. Essentially, they get stuck partway down.

Particularly in the western Pacific Ocean, near Japan and at the Mariana Trench, for example, the slabs of crust seem to stall out at around 416 miles (670 km) deep. In these areas, they seem to deflect and travel horizontally as much as 1,243 miles (2,000 km).

The layer of mantle at that particular depth is unusual, Zhong said, because the rock there goes through a sudden density increase, which is the result of the pressure of all the rock pushing down on top of it. In the new study, Zhong and University of Colorado graduate student Wei Mao built a computer model of the mantle's dynamics, including both this density increase and the past 130 million years of continental plate movements.

This more complete model of the mantle naturally produced the same sort of stagnating slabs seen in the real mantle, the researchers found. What seems to be going on, Zhong said, is that the accumulated pressure of the overlying rock at 670 km creates an area of reduced viscosity - in essence, the mantle is more slippery and less gooey.

"That reduced viscosity essentially provides what we call lubrication on the slabs," Zhong said. The chunks of crust are able to slip and slide sideways instead of continuing their downward plunge.

This hitch in the machine is only temporary. The slabs are probably only trapped for 20 million years or so, Zhong said - a blink of the eye in terms of Earth's history. But their dynamics might be important for some of the geological phenomena seen on the surface. For example, volcanic activity in northeastern China, far from the volcanic arc of Japan, could be due, in part, to some of these slab dynamics, Zhong said.

The model doesn't answer all the questions about the stagnating slabs. It's not clear, Zhong said, why the western Pacific seems to give rise to so many of these stagnant slabs, while subduction zones near North and South America currently don't. There are also other mystery spots around the globe, he said.

"In places like New Zealand, there is still some disagreement between our convection model and the observations," he said, "so we need to reconcile those places."

Original article on Live Science.

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Scientists Find Weird Reason Diving Plates Get Stuck 400 Miles Beneath Earth's Surface

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The Earth's mantle acts like a giant churn, circulating cool oceanic crust downward toward the core, where it heats up into a goopy solid and then rises again - a process that powers everything from plate tectonics to volcanism.

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A new study suggests that plate tectonics -- a scientific theory that divides Earth into large chunks of crust that move slowly over hot viscous mantle rock -- could have been active from the planet's very beginning. The new findings defy previous beliefs that tectonic plates were developed over the course of billions of years.

The paper, published in Earth and Planetary Science Letters, has important implications in the fields of geochemistry and geophysics. For example, a better understanding of plate tectonics could help predict whether planets beyond our solar system could be hospitable to life.

"Plate tectonics set up the conditions for life," said Nick Dygert, assistant professor of petrology and geochemistry in UT's Department of Earth and Planetary Sciences and coauthor of the study. "The more we know about ancient plate tectonics, the better we can understand how Earth got to be the way it is now."

For the research, Dygert and his team looked into the distribution of two very specific noble gas isotopes: Helium-3 and Neon-22. Noble gases are those that don't react to any other chemical element.

Previous models have explained Earth's current Helium-3/Neon-22 ratio by arguing that a series of large-scale impacts (like the one that produced our moon) resulted in massive magma oceans, which degassed and incrementally increased the ratio each time.

However, Dygert believes the scenario is unlikely.

"While there is no conclusive evidence that this didn't happen," he said, "it could have only raised the Earth's Helium-3/Neon-22 ratio under very specific conditions."

Instead, Dygert and his team believe the Helium-3/Neon-22 ratio raised in a different way.

As Earth's crust is continuously formed, the ratio of helium to neon in the mantle beneath the crust increases. By calculating this ratio in the mantle beneath the crust, and considering how this process would affect the bulk Earth over long periods of time, a rough timeline of Earth's tectonic plate cycling can be established.

"Helium-3 and Neon-22 were produced during the formation of the solar system and not by other means," Dygert said. "As such, they provide valuable insight into Earth's earliest conditions and subsequent geologic activity."

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geology; earthquakes; earth science; natural disasters; near-earth object impacts; tsunamis; environmental issues; geochemistry

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Plate tectonics may have been active on Earth since the very beginning

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A new study suggests that plate tectonics -- a scientific theory that divides the earth into large chunks of crust that move slowly over hot viscous mantle rock -- could have been active from the planet's very beginning. The new findings defy previous beliefs that tectonic plates were developed over the course of billions of years.

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Researchers have discovered a huge chain of ancient, underwater volcanoes about 250 miles (400 kilometers) east of Tasmania. This sonar map shows some of the massive seamounts, beginning about 3 miles (5,000 meters) below the ocean's surface.

Credit: CSIRO

Thanks to an especially slobbery "Looney Tune," the island of Tasmania is best-known for its eponymous devils. But the nearby Tasman Sea is no less rich in oddball biodiversity. Take, for example, the newest discovery reported by the Australian research vessel the Investigator. A team of seafaring scientists has uncovered an ancient highway of massive underwater volcanoes - and those submerged mountains (or "seamounts") are apparently brimming with whales, according to a news release from Australia's national science agency. [ Infographic: Tallest Mountain to Deepest Ocean Trench]

"While we were over the chain of seamounts, the ship was visited by large numbers of humpback and long-finned pilot whales," Eric Woehler, a seabird ecologist at the University of Tasmania and a crewmember aboard the Investigator during its recent expedition, said in a statement. "We estimated that at least 28 individual humpback whales visited us on one day, followed by a pod of 60 to 80 long-finned pilot whales the next."

The research vessel crew spotted nearly 30 humpback whales near their boat in one day. It's possible that the massive, volcanic mountains nearby serve as underwater "signposts" that help the whales find their way to and from their breeding grounds.

Credit: ©Eric Woehler

Woehler and a crew of colleagues had recently embarked on a 25-day tourof the Tasman Sea to study ocean productivity - the process by which microscopic phytoplankton turn sunlight into the carbon that sustains entire ocean ecosystems. While Woehler surveyed the local marine life, other crewmembers scanned for signs of phytoplankton activity and mapped previously uncharted chunks of the ocean floor using a special sonar.

Once the Investigator had sailed about 250 miles (400 kilometers) east of Tasmania, the crew saw spikes in phytoplankton activity. Sonar scans revealed that the activity coincided with the appearance of a gargantuan chain of volcanic mountains submerged thousands of feet below the surface of the sea.

Sonar scans revealed that these hidden, underwater mountain ranges rose up from the seafloor beginning about 3 miles (5,000 meters) below the water's surface. The mounts varied in size and inclination; some were jagged peaks that stabbed up to 2 miles (3,000 m) above the seafloor, while others were vast, low plateaus. But each of the titanic hills and valleys likely formed many millennia ago as a result of ancient volcanic activity in the area, the researchers said.

Today, that variety of terrain likely provides habitats for a hugely diverse population of marine life. The jutting mounts could serve as underwater "signposts" on a migratory highway for regional whales, helping to guide them from their winter breeding grounds to their summer feeding grounds, Woehler said. In addition to the plentiful phytoplankton and whale sightings, the Investigator crew also reported seeing a significant variety of seabirds, including four species of albatrosses and petrels.

"This is a very diverse landscape and will undoubtedly be a biological hotspot that supports a dazzling array of marine life," said Tara Martin, a researcher with the Commonwealth Scientific and Industrial Research Organization (CSIRO), the Australian science agency that owns and operates the Investigator.

Researchers will have to study these newly discovered seamounts further to find out if they are indeed what Woehler called a "highway of marine life." Two fresh expeditions to the area are set to embark in November and December. In these trips, the team plans to bring back high-resolution video of the sea life swarming on and around the ancient seamounts. Stay tuned for the footage on the Investigator's website.

Originally published on Live Science.

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Lost Chain of Underwater Volcanoes Is a Massive Whale Superhighway

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Thanks to an especially slobbery "Looney Tune," the island of Tasmania is best-known for its eponymous devils. But the nearby Tasman Sea is no less rich in oddball biodiversity. Take, for example, the newest discovery reported by the Australian research vessel the Investigator.

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jeremy roos

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The disastrous mortal disease known as the Black Death spread across Europe in the years 1346-53. The frightening name, however, only came several centuries after its visitation (and was probably a mistranslation of the Latin word 'atra' meaning both 'terrible' and 'black)'. Chronicles and letters from the time describe the terror wrought by the illness. In Florence, the great Renaissance poet Petrarch was sure that they would not be believed: 'O happy posterity, who will not experience such abysmal woe and will look upon our testimony as a fable.' A Florentine chronicler relates that,

All the citizens did little else except to carry dead bodies to be buried [...] At every church they dug deep pits down to the water-table; and thus those who were poor who died during the night were bundled up quickly and thrown into the pit. In the morning when a large number of bodies were found in the pit, they took some earth and shovelled it down on top of them; and later others were placed on top of them and then another layer of earth, just as one makes lasagne with layers of pasta and cheese.

The accounts are remarkably similar. The chronicler Agnolo di Tura 'the Fat' relates from his Tuscan home town that

... in many places in Siena great pits were dug and piled deep with the multitude of dead [...] And there were also those who were so sparsely covered with earth that the dogs dragged them forth and devoured many bodies throughout the city.

The tragedy was extraordinary. In the course of just a few months, 60 per cent of Florence's population died from the plague, and probably the same proportion in Siena. In addition to the bald statistics, we come across profound personal tragedies: Petrarch lost to the Black Death his beloved Laura to whom he wrote his famous love poems; Di Tura tells us that 'I [...] buried my five children with my own hands'.

The Black Death was an epidemic of bubonic plague, a disease caused by the bacterium Yersinia pestis that circulates among wild rodents where they live in great numbers and density. Such an area is called a 'plague focus' or a 'plague reservoir'. Plague among humans arises when rodents in human habitation, normally black rats, become infected. The black rat, also called the 'house rat' and the 'ship rat', likes to live close to people, the very quality that makes it dangerous (in contrast, the brown or grey rat prefers to keep its distance in sewers and cellars). Normally, it takes ten to fourteen days before plague has killed off most of a contaminated rat colony, making it difficult for great numbers of fleas gathered on the remaining, but soon- dying, rats to find new hosts. After three days of fasting, hungry rat fleas turn on humans. From the bite site, the contagion drains to a lymph node that consequently swells to form a painful bubo, most often in the groin, on the thigh, in an armpit or on the neck. Hence the name bubonic plague. The infection takes three-five days to incubate in people before they fall ill, and another three-five days before, in 80 per cent of the cases, the victims die. Thus, from the introduction of plague contagion among rats in a human community it takes, on average, twenty-three days before the first person dies.

When, for instance, a stranger called Andrew Hogson died from plague on his arrival in Penrith in 1597, and the next plague case followed twenty-two days later, this corresponded to the first phase of the development of an epidemic of bubonic plague. And Hobson was, of course, not the only fugitive from a plague-stricken town or area arriving in various communities in the region with infective rat fleas in their clothing or luggage. This pattern of spread is called 'spread by leaps' or 'metastatic spread'. Thus, plague soon broke out in other urban and rural centres, from where the disease spread into the villages and townships of the surrounding districts by a similar process of leaps.

In order to become an epidemic the disease must be spread to other rat colonies in the locality and transmitted to inhabitants in the same way. It took some time for people to recognize that a terrible epidemic was breaking out among them and for chroniclers to note this. The timescale varies: in the countryside it took about forty days for realisation to dawn; in most towns with a few thousand inhabitants, six to seven weeks; in the cities with over 10,000 inhabitants, about seven weeks, and in the few metropolises with over 100,000 inhabitants, as much as eight weeks.

Plague bacteria can break out of the buboes and be carried by the blood stream to the lungs and cause a variant of plague that is spread by contaminated droplets from the cough of patients (pneumonic plague). However, contrary to what is sometimes believed, this form is not contracted easily, spreads normally only episodically or incidentally and constitutes therefore normally only a small fraction of plague cases. It now appears clear that human fleas and lice did not contribute to the spread, at least not significantly. The bloodstream of humans is not invaded by plague bacteria from the buboes, or people die with so few bacteria in the blood that bloodsucking human parasites become insufficiently infected to become infective and spread the disease: the blood of plague-infected rats contains 500-1,000 times more bacteria per unit of measurement than the blood of plague-infected humans.

Importantly, plague was spread considerable distances by rat fleas on ships. Infected ship rats would die, but their fleas would often survive and find new rat hosts wherever they landed. Unlike human fleas, rat fleas are adapted to riding with their hosts; they readily also infest clothing of people entering affected houses and ride with them to other houses or localities. This gives plague epidemics a peculiar rhythm and pace of development and a characteristic pattern of dissemination. The fact that plague is transmitted by rat fleas means plague is a disease of the warmer seasons, disappearing during the winter, or at least lose most of their powers of spread. The peculiar seasonal pattern of plague has been observed everywhere and is a systematic feature also of the spread of the Black Death. In the plague history of Norway from the Black Death 1348-49 to the last outbreaks in 1654, comprising over thirty waves of plague, there was never a winter epidemic of plague. Plague is very different from airborne contagious diseases, which are spread directly between people by droplets: these thrive in cold weather.

This conspicuous feature constitutes proof that the Black Death and plague in general is an insect-borne disease. Cambridge historian John Hatcher has noted that there is 'a remarkable transformation in the seasonal pattern of mortality in England after 1348': whilst before the Black Death the heaviest mortality was in the winter months, in the following century it was heaviest in the period from late July to late September. He points out that this strongly indicates that the 'transformation was caused by the virulence of bubonic plague'.

***

Another very characteristic feature of the Black Death and plague epidemics in general, both in the past and in the great outbreaks in the early twentieth century, reflects their basis in rats and rat fleas: much higher proportions of inhabitants contract plague and die from it in the countryside than in urban centres. In the case of English plague history, this feature has been underlined by Oxford historian Paul Slack. When around 90 per cent of the population lived in the countryside, only a disease with this property combined with extreme lethal powers could cause the exceptional mortality of the Black Death and of many later plague epidemics. All diseases spread by cross-infection between humans, on the contrary, gain increasing powers of spread with increasing density of population and cause highest mortality rates in urban centres.

Lastly it could be mentioned that scholars have succeeded in extracting genetic evidence of the causal agent of bubonic plague, the DNA-code of Yersinia pestis, from several plague burials in French cemeteries from the period 1348-1590.

It used to be thought that the Black Death originated in China, but new research shows that it began in the spring of 1346 in the steppe region, where a plague reservoir stretches from the north-western shores of the Caspian Sea into southern Russia. People occasionally contract plague there even today. Two contemporary chroniclers identify the estuary of the river Don where it flows into the Sea of Azov as the area of the original outbreak, but this could be mere hearsay, and it is possible that it started elsewhere, perhaps in the area of the estuary of the river Volga on the Caspian Sea. At the time, this area was under the rule of the Mongol khanate of the Golden Horde. Some decades earlier the Mongol khanate had converted to Islam and the presence of Christians, or trade with them, was no longer tolerated. As a result the Silk Road caravan routes between China and Europe were cut off. For the same reason the Black Death did not spread from the east through Russia towards western Europe, but stopped abruptly on the Mongol border with the Russian principalities. As a result, Russia which might have become the Black Death's first European conquest, in fact was its last, and was invaded by the disease not from the east but from the west.

The epidemic in fact began with an attack that the Mongols launched on the Italian merchants' last trading station in the region, Kaffa (today Feodosiya) in the Crimea. In the autumn of 1346, plague broke out among the besiegers and from them penetrated into the town. When spring arrived, the Italians fled on their ships. And the Black Death slipped unnoticed on board and sailed with them.

***

The extent of the contagious power of the Black Death has been almost mystifying. The central explanation lies within characteristic features of medieval society in a dynamic phase of modernisation heralding the transformation from a medieval to early modern European society. Early industrial market-economic and capitalistic developments had advanced more than is often assumed, especially in northern Italy and Flanders. New, larger types of ship carried great quantities of goods over extensive trade networks that linked Venice and Genoa with Constantinople and the Crimea, Alexandria and Tunis, London and Bruges. In London and Bruges the Italian trading system was linked to the busy shipping lines of the German Hanseatic League in the Nordic countries and the Baltic area, with large broad-bellied ships called cogs. This system for long-distance trade was supplemented by a web of lively short and medium-distance trade that bound together populations all over the Old World.

The strong increase in population in Europe in the High Middle Ages (1050-1300) meant that the prevailing agricultural technology was inadequate for further expansion. To accommodate the growth, forests were cleared and mountain villages settled wherever it was possible for people to eke out a living. People had to opt for a more one-sided husbandry, particularly in animals, to create a surplus that could be traded for staples such as salt and iron, grain or flour. These settlements operated within a busy trading network running from coasts to mountain villages. And with tradesmen and goods, contagious diseases reached even the most remote and isolated hamlets.

In this early phase of modernisation, Europe was also on the way to 'the golden age of bacteria', when there was a great increase in epidemic diseases caused by increases in population density and in trade and transport while knowledge of the nature of epidemics, and therefore the ability to organise efficient countermeasures to them, was still minimal. Most people believed plague and mass illness to be a punishment from God for their sins. They responded with religious penitential acts aimed at tempering the Lord's wrath, or with passivity and fatalism: it was a sin to try to avoid God's will.

Much new can be said on the Black Death's patterns of territorial spread. Of particular importance was the sudden appearance of the plague over vast distances, due to its rapid transportation by ship. Ships travelled at an average speed of around 40km a day which today seems quite slow. However, this speed meant that the Black Death easily moved 600km in a fortnight by ship: spreading, in contemporary terms, with astonishing speed and unpredictability. By land, the average spread was much slower: up to 2km per day along the busiest highways or roads and about 0.6km per day along secondary lines of communication.

As already noted, the pace of spread slowed strongly during the winter and stopped completely in mountain areas such as the Alps and the northerly parts of Europe. Yet, the Black Death often rapidly established two or more fronts and conquered countries by advancing from various quarters.

Italian ships from Kaffa arrived in Constantinople in May 1347 with the Black Death on board. The epidemic broke loose in early July. In North Africa and the Middle East, it started around September 1st, having arrived in Alexandria with ship transport from Constantinople. Its spread from Constantinople to European Mediterranean commercial hubs also started in the autumn of 1347. It reached Marseilles by about the second week of September, probably with a ship from the city. Then the Italian merchants appear to have left Constantinople several months later and arrived in their home towns of Genoa and Venice with plague on board, some time in November. On their way home, ships from Genoa also contaminated Florence's seaport city of Pisa. The spread out of Pisa is characterized by a number of metastatic leaps. These great commercial cities also functioned as bridgeheads from where the disease conquered Europe.

In Mediterranean Europe, Marseilles functioned as the first great centre of spread. The relatively rapid advance both northwards up the Rhône valley to Lyons and south-westwards along the coasts towards Spain - in chilly months with relatively little shipping activity - is striking. As early as March 1348, both Lyon's and Spain's Mediterranean coasts were under attack.

En route to Spain, the Black Death also struck out from the city of Narbonne north-westwards along the main road to the commercial centre of Bordeaux on the Atlantic coast, which by the end of March had become a critical new centre of spread. Around April 20th, a ship from Bordeaux must have arrived in La Coruña in northwestern Spain; a couple of weeks later another ship from there let loose the plague in Navarre in northeastern Spain. Thus, two northern plague fronts were opened less than two months after the disease had invaded southern Spain.

Another plague ship sailed from Bordeaux, northwards to Rouen in Normandy where it arrived at the end of April. There, in June, a further plague front moved westwards towards Brittany, south-eastwards towards Paris and northwards in the direction of the Low Countries.

Yet another ship bearing plague left Bordeaux a few weeks later and arrived around May 8th, in the southern English town of Melcombe Regis, part of present-day Weymouth in Dorset: the epidemic broke out shortly before June 24th. The significance of ships in the rapid transmission of contagion is underscored by the fact that at the time the Black Death landed in Weymouth it was still in an early phase in Italy. From Weymouth, the Black Death spread not only inland, but also in new metastatic leaps by ships, which in some cases must have travelled earlier than the recognized outbreaks of the epidemic: Bristol was contaminated in June, as were the coastal towns of the Pale in Ireland; London was contaminated in early August since the epidemic outbreak drew comment at the end of September. Commercial seaport towns like Colchester and Harwich must have been contaminated at about the same time. From these the Black Death spread inland. It is now also clear that the whole of England was conquered in the course of 1349 because, in the late autumn of 1348, ship transport opened a northern front in England for the Black Death, apparently in Grimsby.

***

The early arrival of the Black Death in England and the rapid spread to its southeastern regions shaped much of the pattern of spread in Northern Europe. The plague must have arrived in Oslo in the autumn of 1348, and must have come with a ship from south-eastern England, which had lively commercial contacts with Norway. The outbreak of the Black Death in Norway took place before the disease had managed to penetrate southern Germany, again illustrating the great importance of transportation by ship and the relative slowness of spread by land. The outbreak in Oslo was soon stopped by the advent of winter weather, but it broke out again in the early spring. Soon it spread out of Oslo along the main roads inland and on both sides of the Oslofjord. Another independent introduction of contagion occurred in early July 1349 in the town of Bergen; it arrived in a ship from England, probably from King's Lynn. The opening of the second plague front was the reason that all Norway could be conquered in the course of 1349. It disappeared completely with the advent of winter, the last victims died at the turn of the year.

The early dissemination of the Black Death to Oslo, which prepared the ground for a full outbreak in early spring, had great significance for the pace and pattern of the Black Death's further conquest of Northern Europe. Again ship transport played a crucial role, this time primarily by Hanseatic ships fleeing homewards from their trading station in Oslo with goods acquired during the winter. On their way the seaport of Halmstad close to the Sound was apparently contaminated in early July. This was the starting point for the plague's conquest of Denmark and Sweden, which was followed by several other independent introductions of plague contagion later; by the end of 1350 most of these territories had been ravaged.

However, the voyage homewards to the Hanseatic cities on the Baltic Sea had started significantly earlier. The outbreak of the Black Death in the Prussian town of Elbing (today the Polish town of Elblag) on August 24th, 1349, was a new milestone in the history of the Black Death. A ship that left Oslo at the beginning of June would probably sail through the Sound around June 20th and reach Elbing in the second half of July, in time to unleash an epidemic outbreak around August 24th. Other ships that returned at the end of the shipping season in the autumn from the trading stations in Oslo or Bergen, brought the Black Death to a number of other Hanseatic cities both on the Baltic Sea and the North Sea. The advent of winter stopped the outbreaks initially as had happened elsewhere, but contagion was spread with goods to commercial towns and cities deep into northern Germany. In the spring of 1350, a northern German plague front was formed that spread southwards and met the plague front which in the summer of 1349 had formed in southern Germany with importation of contagion from Austria and Switzerland.

***

Napoleon did not succeed in conquering Russia. Hitler did not succeed. But the Black Death did. It entered the territory of the city state of Novgorod in the late autumn of 1351 and reached the town of Pskov just before the winter set in and temporarily suppressed the epidemic; thus the full outbreak did not start until the early spring of 1352. In Novgorod itself, the Black Death broke out in mid-August. In 1353, Moscow was ravaged, and the disease also reached the border with the Golden Horde, this time from the west, where it petered out. Poland was invaded by epidemic forces coming both from Elbing and from the northern German plague front and, apparently, from the south by contagion coming across the border from Slovakia via Hungary.

Iceland and Finland are the only regions that, we know with certainty, avoided the Black Death because they had tiny populations with minimal contact abroad. It seems unlikely that any other region was so lucky.

How many people were affected? Knowledge of general mortality is crucial to all discussions of the social and historical impact of the plague. Studies of mortality among ordinary populations are far more useful, therefore, than studies of special social groups, whether monastic communities, parish priests or social elites. Because around 90 per cent of Europe's population lived in the countryside, rural studies of mortality are much more important than urban ones.

Researchers generally used to agree that the Black Death swept away 20-30 per cent of Europe's population. However, up to 1960 there were only a few studies of mortality among ordinary people, so the basis for this assessment was weak. From 1960, a great number of mortality studies from various parts of Europe were published. These have been collated and it is now clear that the earlier estimates of mortality need to be doubled. No suitable sources for the study of mortality have been found in the Muslim countries that were ravaged.

The mortality data available reflects the special nature of medieval registrations of populations. In a couple of cases, the sources are real censuses recording all members of the population, including women and children. However, most of the sources are tax registers and manorial registers recording households in the form of the names of the householders. Some registers aimed at recording all households, also the poor and destitute classes who did not pay taxes or rents, but the majority recorded only householders who paid tax to the town or land rent to the lord of the manor. This means that they overwhelmingly registered the better-off adult men of the population, who for reasons of age, gender and economic status had lower mortality rates in plague epidemics than the general population. According to the extant complete registers of all households, the rent or tax-paying classes constituted about half the population both in the towns and in the countryside, the other half were too poor. Registers that yield information on both halves of the populations indicate that mortality among the poor was 5-6 per cent higher. This means that in the majority of cases when registers only record the better-off half of the adult male population, mortality among the adult male population as a whole can be deduced by adding 2.5-3 per cent.

Another fact to consider is that in households where the householder survived, other members often died. For various reasons women and children suffer higher incidence of mortality from plague than adult men. A couple of censuses produced by city states in Tuscany in order to establish the need for grain or salt are still extant. They show that the households were, on average, reduced in the countryside from 4.5 to 4 persons and in urban centres from 4 to 3.5 persons. All medieval sources that permit the study of the size and composition of households among the ordinary population produce similar data, from Italy in southern Europe to England in the west and Norway in northern Europe. This means that the mortality among the registered households as a whole was 11-12.5 per cent higher than among the registered householders.

Detailed study of the mortality data available points to two conspicuous features in relation to the mortality caused by the Black Death: namely the extreme level of mortality caused by the Black Death, and the remarkable similarity or consistency of the level of mortality, from Spain in southern Europe to England in north-western Europe. The data is sufficiently widespread and numerous to make it likely that the Black Death swept away around 60 per cent of Europe's population. It is generally assumed that the size of Europe's population at the time was around 80 million. This implies that that around 50 million people died in the Black Death. This is a truly mind-boggling statistic. It overshadows the horrors of the Second World War, and is twice the number murdered by Stalin's regime in the Soviet Union. As a proportion of the population that lost their lives, the Black Death caused unrivalled mortality.

This dramatic fall in Europe's population became a lasting and characteristic feature of late medieval society, as subsequent plague epidemics swept away all tendencies of population growth. Inevitably it had an enormous impact on European society and greatly affected the dynamics of change and development from the medieval to Early Modern period. A historical turning point, as well as a vast human tragedy, the Black Death of 1346-53 is unparalleled in human history.

Ole J. Benedictow is Emeritus Professor of History at the Universtiy of Oslo, Norway.
Further Reading:

The Black Death, 1346-1353. The Complete History (Boydell & Brewer, 2004)

Ole J. Benedictow, 'Plague in the Late Medieval Nordic Countries', Epidemiological Studies (1996)

M.W. Dols,The Black Death in the Middle East (Princeton, 1970)

J. Hatcher,Plague, Population and the English Economy 1348-1530 (Basingstoke, 1977)

J. Hatcher 'England in the Aftermath of the Black Death' (Past & Present, 1994)

L.F. Hirst, The Conquest of Plague (Oxford, 1953).

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The Black Death: The Greatest Catastrophe Ever

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The disastrous mortal disease known as the Black Death spread across Europe in the years 1346-53. The frightening name, however, only came several centuries after its visitation (and was probably a mistranslation of the Latin word 'atra' meaning both 'terrible' and 'black)'. Chronicles and letters from the time describe the terror wrought by the illness.

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A giant ring of black holes has been discovered 300 million light-years away, offering new clues about what happens when galaxies collide.

Using NASA's Chandra X-ray Observatory, astronomers detected a very bright source of X-rays that is likely fueled by either a ring of stellar-mass black holes or neutron stars - the small, dense corpses left after stellar explosions, - according to a new study.

The bright X-ray source emanates from the ring galaxy AM 0644-741 (abbreviated AM 0644), which lies approximately 300 million light-years from Earth. By combining data from Chandra and NASA's Hubble Space Telescope, astronomers created a composite image of X-ray and optical observations of the galaxy. [ Images: Black Holes of the Universe]

The observed ring of black holes or neutron stars is believed to be the result of a galaxy collision. The galaxies were likely drawn together by gravity, and the gravitational force from one galaxy created waves in the gas surrounding its neighbor, which, in this case, is AM 0644. The ripples would have then caused the gas to expand or clump together in denser areas, triggering the birth of new stars.

A composite image of the ring galaxy AM 0644-741. The image includes X-ray data from the Chandra X-ray Observatory (purple) and optical data from NASA's Hubble Space Telescope (red, green and blue). The galaxy AM 0644 is located in the lower right.

Credit: NASA/CXC/INAF/A. Wolter et al; NASA/STScI

"The most massive of these fledgling stars will lead short lives - in cosmic terms - of millions of years," representatives from the Chandra X-ray Observatory said in a statement. "After that, their nuclear fuel is spent, and the stars explode as supernovas, leaving behind either black holes with masses typically between about five to twenty times that of the sun, or neutron stars with a mass approximately equal to that of the sun."

The black holes or neutron stars have close cosmic companions from which they siphon gas. This gas falls inward and is heated by friction, creating the bright X-rays detected by Chandra, according to the statement.

What's more, the bright X-rays from AM 0644 are classified as ultraluminous X-ray sources (ULXs). These objects produce hundreds to thousands of times more X-rays than most other neutron star or black-hole X-ray binaries. However, the identity of the individual ULXs in AM 0644 is currently unknown, according to the statement.

In addition to the ring of black holes or neutron stars surrounding AM 0644, the Chandra data revealed a supermassive black hole located at the center of the galaxy, as well as a rapidly growing black hole that's located well behind the galaxy at a distance of 9.1 billion light-years from Earth.

And AM 0644 wasn't the only ring galaxy Chandra inspected. The telescope observed six other ring galaxies, revealing a total of 63 X-ray sources, 50 of which are considered ULXs.

In fact, the seven ring galaxies contain a higher number of ULXs per galaxy than other types of galaxies. Therefore, these galaxies could help astronomers better understand the origin of ULXs, according to the statement.

The study was published Aug. 10 in The Astrophysical Journal and is available online.

Follow Samantha Mathewson @Sam_Ashley13. Follow us @Spacedotcom, Facebook and Google+. Original article on Space.com.

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Galaxy Punches Through Neighbor to Spawn Giant Ring of Black Holes

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A giant ring of black holes has been discovered 300 million light-years away, offering new clues about what happens when galaxies collide. Using NASA's Chandra X-ray Observatory, astronomers detected a very bright source of X-rays that is likely fueled by either a ring of stellar-mass black holes or neutron stars - the small, dense corpses left after stellar explosions, - according to a new study.

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Highlights for penicillin V

1. Penicillin V oral tablet is only available as a generic drug.

2. Penicillin V also comes as an oral solution.

3. Penicillin V oral tablet is used to treat certain infections caused by bacteria. It won't work for infections caused by viruses, such as the common cold.

Penicillin V is a prescription drug that comes as an oral tablet and an oral solution.

Penicillin V oral tablet is only available as a generic drug.

Why it's used

Penicillin V oral tablet is used to treat certain infections caused by bacteria. It won't work to treat infections caused by viruses, such as the common cold. Bacterial infections this drug is used to treat include:

streptococcal upper respiratory tract infections, scarlet fever, and erysipelas infections

pneumococcal upper respiratory infections

staphylococcal skin and soft tissue infections

fusospirochetosis (infection of the oropharynx or middle part of the throat)

prevention of rheumatic fever and chorea

This drug may be used as part of a combination therapy. This means you may need to take it with other medications.

How it works

Penicillin V belongs to a class of drugs called antibiotics. A class of drugs is a group of medications that work in a similar way. These drugs are often used to treat similar conditions.

Penicillin V works by stopping the bacteria from multiplying. This kills off the bacteria that are causing your infection.

Penicillin V oral tablet doesn't cause drowsiness. However, it may cause other side effects.

More common side effects

The more common side effects of penicillin V can include:

If these effects are mild, they may go away within a few days or a couple of weeks. If they're more severe or don't go away, talk to your doctor or pharmacist.

Serious side effects

Call your doctor right away if you have serious side effects. Call 911 if your symptoms feel life-threatening or if you think you're having a medical emergency. Serious side effects and their symptoms can include the following:

Allergic reaction. Symptoms can include:

skin rash with or without blisters

flu-like symptoms, such as a fever, feeling ill, or joint pain

swelling of your throat, tongue, or mouth

Diarrhea. Symptoms include:
bloody or watery diarrhea with or without stomach cramps and a fever

Disclaimer: Our goal is to provide you with the most relevant and current information. However, because drugs affect each person differently, we cannot guarantee that this information includes all possible side effects. This information is not a substitute for medical advice. Always discuss possible side effects with a healthcare provider who knows your medical history.

Penicillin V oral tablet can interact with other medications, vitamins, or herbs you may be taking. An interaction is when a substance changes the way a drug works. This can be harmful or prevent the drug from working well.

To help prevent interactions, your doctor should manage all of your medications carefully. Be sure to tell your doctor about all medications, vitamins, or herbs you're taking. To find out how this drug might interact with something else you're taking, talk to your doctor or pharmacist.

Disclaimer: Our goal is to provide you with the most relevant and current information. However, because drugs interact differently in each person, we cannot guarantee that this information includes all possible interactions. This information is not a substitute for medical advice. Always speak with your healthcare provider about possible interactions with all prescription drugs, vitamins, herbs and supplements, and over-the-counter drugs that you are taking.

This dosage information is for penicillin V oral tablet. All possible dosages and drug forms may not be included here. Your dosage, drug form, and how often you take the drug will depend on:

your age

the condition being treated

the severity of your condition

other medical conditions you have

how you react to the first dose

Forms and strengths

Generic: Penicillin V

Dosage for streptococcal infection
Adult dosage (ages 18 years and older)
Typical dosage: 125-250 mg taken every 6-8 hours for 10 days.
Child dosage (ages 12-17 years)
Typical dosage: 125-250 mg taken every 6-8 hours for 10 days.
Child dosage (ages 0-11 years)
It hasn't been confirmed that this drug is safe and effective for use in people younger than 12 years.

Dosage for pneumococcal upper respiratory infection
Adult dosage (ages 18 years and older)
Typical dosage: 250-500 mg taken every 6 hours until you no longer have a fever for at least 2 days.
Child dosage (ages 12-17 years)
Typical dosage: 250-500 mg taken every 6 hours until you no longer have a fever for at least 2 days.
Child dosage (ages 0-11 years)
It hasn't been confirmed that this drug is safe and effective for use in people younger than 12 years.

Dosage for staphylococcal skin or soft tissue infection
Adult dosage (ages 18 years and older)
Typical dosage: 250-500 mg taken every 6-8 hours.
Child dosage (ages 12-17 years)
Typical dosage: 250-500 mg taken every 6-8 hours.
Child dosage (ages 0-11 years)
It hasn't been confirmed that this drug is safe and effective for use in people younger than 12 years.

Dosage for prevention of rheumatic fever or chorea or both
Adult dosage (ages 18 years and older)
Typical dosage: 125-250 mg taken two times per day.
Child dosage (ages 12-17 years)
Typical dosage: 125-250 mg taken two times per day.
Child dosage (ages 0-11 years)
It hasn't been confirmed that this drug is safe and effective for use in people younger than 12 years.

Dosage for fusospirochetosis (oropharynx infection)
Adult dosage (ages 18 years and older)
Typical dosage: 250-500 mg taken every 6-8 hours.
Child dosage (ages 12-17 years)
Typical dosage: 250-500 mg taken every 6-8 hours.
Child dosage (ages 0-11 years)
It hasn't been confirmed that this drug is safe and effective for use in people younger than 12 years.

Disclaimer: Our goal is to provide you with the most relevant and current information. However, because drugs affect each person differently, we cannot guarantee that this list includes all possible dosages. This information is not a substitute for medical advice. Always speak with your doctor or pharmacist about dosages that are right for you.

Penicillin V oral tablet is used for short-term treatment. It comes with serious risks if you don't take it as prescribed.

If you stop taking the drug suddenly or don't take it at all: Your infection may not get better or may get worse. Even if you're starting to feel better, you should still finish all of your medication.

If you miss doses or don't take the drug on schedule: Your medication may not work as well or may stop working completely. For this drug to work well, a certain amount needs to be in your body at all times.

If you take too much: You could have dangerous levels of this drug in your body. Symptoms of an overdose of this drug can include:

Diarrhea

Nausea

Oral infection. Symptoms can include:

creamy white lesions that look like cottage cheese

cotton mouth (dry mouth)

Vomiting

Blackened tongue

If you think you've taken too much of this drug, call your doctor or seek guidance from the American Association of Poison Control Centers at 1-800-222-1222 or through their online tool. But if your symptoms are severe, call 911 or go to the nearest emergency room right away.

What to do if you miss a dose: Take your dose as soon as you remember. But if you remember just a few hours before your next scheduled dose, take only one dose. Never try to catch up by taking two doses at once. This could result in dangerous side effects.

How to tell if the drug is working: Your symptoms and your infection should get better.

Keep these considerations in mind if your doctor prescribes penicillin V oral tablet for you.

General

Do not take this drug with food. Take it on an empty stomach, at least 1 hour before eating or 2 hours after eating.

You can cut or crush the tablet.

Storage

Store this drug at room temperature. Keep it between 68°F and 77°F (15°C and 30°C).

Keep the container tightly closed.

Don't store this medication in moist or damp areas, such as bathrooms.

Refills

A prescription for this medication is refillable. You should not need a new prescription for this medication to be refilled. Your doctor will write the number of refills authorized on your prescription.

Travel

When traveling with your medication:

Always carry your medication with you. When flying, never put it into a checked bag. Keep it in your carry-on bag.

Don't worry about airport X-ray machines. They can't hurt your medication.

You may need to show airport staff the pharmacy label for your medication. Always carry the original prescription-labeled container with you.

Don't put this medication in your car's glove compartment or leave it in the car. Be sure to avoid doing this when the weather is very hot or very cold.

Clinical monitoring

Your doctor may do blood tests to check how well your kidneys are working. If your kidneys aren't working well, your doctor may lower your dose of this drug.

There are other drugs available to treat your condition. Some may be better suited for you than others. Talk to your doctor about other drug options that may work for you.

Serious allergic reaction warning: This drug can cause a severe allergic reaction. Symptoms include a skin rash with or without blisters, flu-like symptoms (such as a fever, feeling ill, or joint pain), or swelling of your throat, tongue, or mouth. If you have an allergic reaction, call your doctor or local poison control center right away. If your symptoms are severe, call 911 or go to the nearest emergency room. Don't take this drug again if you've ever had an allergic reaction to it.

Severe diarrhea warning: This drug may cause diarrhea during and after your treatment with it. This diarrhea can be caused by an infection in your intestine called Clostridium difficile. Call your doctor right away if you have bloody or watery diarrhea with or without stomach cramps and a fever while you're taking this drug.

Prescription completion warning: It's important you finish all of your penicillin V prescription even if you're feeling better. If you skip doses or don't complete the full course of treatment, this drug won't work as well. Also, the bacteria causing your infection may become resistant to treatment. Resistance means that it won't respond to penicillin V or other antibiotics in the future.

Allergy warning

Penicillin V can cause a severe allergic reaction. Symptoms can include:

skin rash with or without blisters

flu-like symptoms, such as a fever, feeling ill, or joint pain

swelling of your throat, tongue, or mouth

If you have an allergic reaction, call your doctor or local poison control center right away. If your symptoms are severe, call 911 or go to the nearest emergency room.

Don't take this drug again if you've ever had an allergic reaction to it or any other type of penicillin. Taking it again could be fatal (cause death).

If you have severe allergies, you have a higher risk of developing a severe allergic reaction to penicillin. This type of allergic reaction is called anaphylaxis. Symptoms can include throat swelling, trouble swallowing, wheezing, and trouble breathing.

Warnings for people with certain health conditions

For people with asthma: If you have asthma, you have a higher risk of developing a severe allergic reaction to penicillin. This type of allergic reaction is called anaphylaxis. Symptoms can include throat swelling, trouble swallowing, wheezing, and trouble breathing.

For people with kidney problems: If you have kidney problems or a history of kidney disease, you may not be able to clear this drug from your body well. This may increase the levels of penicillin V in your body and cause more side effects.

Warnings for other groups

For pregnant women: The Food and Drug Administration (FDA) hasn't assigned a pregnancy category to penicillin V. It is not yet known if penicillin V is safe and effective for use in pregnant women. Tell your doctor if you're pregnant or plan to become pregnant. Penicillin V should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.

For women who are breastfeeding: Penicillin V may pass into breast milk and may cause side effects in a child who is breastfed. Talk to your doctor if you breastfeed your child. You may need to decide whether to stop breastfeeding or stop taking this medication.

For seniors: The kidneys of older adults may not work as well as they used to. This can cause your body to process drugs more slowly. As a result, more of a drug stays in your body for a longer time. This raises your risk of side effects.

For children: This drug hasn't been studied in children. It shouldn't be used in people younger than 12 years of age.

Disclaimer: Healthline has made every effort to make certain that all information is factually correct, comprehensive, and up-to-date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or other healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.

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Penicillin V | Side Effects, Dosage, Uses, and More

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Penicillin V oral tablet is a prescription drug. It's used to treat bacterial infections such as scarlet fever and certain upper respiratory tract and skin infections, and to prevent rheumatic fever and chorea. The tablet is only available as a generic drug. Learn about side effects, warnings, dosage, and more.

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A team of astronomers using the latest set of data from ESA's Gaia mission to look for high-velocity stars being kicked out of the Milky Way were surprised to find stars instead sprinting inwards -- perhaps from another galaxy. The study is published in the journal Monthly Notices of the Royal Astronomical Society.

Stars circle around our galaxy at hundreds of kilometres per second, and their motions contain a wealth of information about the past history of the Galaxy. The fastest class of these stars are called hypervelocity stars, which are thought to start their life near the Galactic centre, later to be flung towards the edge of the Milky Way via interactions with the black hole at its centre.

Only a small number of hypervelocity stars have ever been discovered, and Gaia's recently published second data release provides a unique opportunity to look for more of them.

"Of the seven million Gaia stars with full 3D velocity measurements, we found twenty that could be travelling fast enough to eventually escape from the Milky Way," explains Elena Maria Rossi, one of the authors of the new study, based at Leiden University, in the Netherlands.

However, the team were in for a surprise: "Rather than flying away from the Galactic centre, most of the high-velocity stars we spotted seem to be racing towards it," adds co-author Tommaso Marchetti. "These could be stars from another galaxy, zooming right through the Milky Way."

It is possible that these intergalactic interlopers come from the Large Magellanic Cloud, a relatively small galaxy orbiting the Milky Way, or they may originate from a galaxy even further afield. If that is the case, they carry the imprint of their site of origin, and studying them at much closer distances than their parent galaxy could provide unprecedented information on the nature of stars in another galaxy -- similar in a way to studying Martian material brought to our planet by meteorites.

"Stars can be accelerated to high velocities when they interact with a supermassive black hole," Elena explains. "So the presence of these stars might be a sign of such black holes in nearby galaxies. But the stars may also have once been part of a binary system, flung towards the Milky Way when their companion star exploded as a supernova. Either way, studying them could tell us more about these kinds of processes in nearby galaxies."

An alternative explanation is that the newly identified sprinting stars could be native to our Galaxy's halo, accelerated and pushed inwards through interactions with one of the dwarf galaxies that fell towards the Milky Way during its build-up history. Additional information about the age and composition of the stars could help the astronomers clarify their origin.

New data will help to nail down the nature and origin of these stars with more certainty, and the team will use ground-based telescopes to find out more about them. At least two more Gaia data releases are planned in the 2020s, and each will provide both more precise and new information on a larger set of stars.

"We eventually expect full 3D velocity measurements for up to 150 million stars," explains co-author Anthony Brown, chair of the Gaia Data Processing and Analysis Consortium Executive. "This will help find hundreds or thousands of hypervelocity stars, understand their origin in much more detail, and use them to investigate the Galactic centre environment as well as the history of our Galaxy," he adds.

"This exciting result shows that Gaia is a true discovery machine, providing the ground for completely unexpected discoveries about our Galaxy," concludes Timo Prusti, Gaia project scientist at ESA.

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galaxies; stars; astrophysics; astronomy; nebulae; black holes; cosmology; esa

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Gaia spots stars flying between galaxies

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A team of astronomers using the latest set of data from ESA's Gaia mission to look for high-velocity stars being kicked out of the Milky Way were surprised to find stars instead sprinting inwards -- perhaps from another galaxy. The study is published in the journal Monthly Notices of the Royal Astronomical Society.

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https://www.cnn.com/2013/08/23/us/hurricane-katrina-statistics-fast-facts/index.html

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jeremy

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This story was originally published on Smarter Than That in 2008. We are republishing a lightly edited version on Popular Science in light of recent interest in the subject.

Humanity has known Earth is round for a few millenia, and I've been meaning to show more methods that prove the world is not flat. I've had a few ideas on how to do that, but recently got an interesting incentive, when Phil Plait, The Bad Astronomer, wrote about a recently published BBC article about "The Flat Earth" society. (Most recently, rapper B.o.B. went on a Twitter rant on the topic.) Phil claims it's ridiculous to even bother rebutting the Flat Earth Society-and I tend to agree. But the history of our species' intellectual pursuit is important and interesting. You don't need to denounce all science and knowledge and believe in a kooky conspiracy theory to enjoy some historical factoids about humanity's quest for space.

On we go, to the top 10 ways to know the Earth is unequivocally, absolutely, positively, 100% not flat!

1. The Moon

Now that humanity knows quite positively that the Moon is not a piece of cheese or a playful god, the phenomena that accompany it (from its monthly cycles to lunar eclipses) are well-explained. It was quite a mystery to the ancient Greeks, though, and in their quest for knowledge, they came up with a few insightful observations that helped humanity figure out the shape of our planet.

Aristotle (who made quite a lot of observations about the spherical nature of the Earth) noticed that during lunar eclipses (when the Earth's orbit places it directly between the Sun and the Moon, creating a shadow in the process), the shadow on the Moon's surface is round. This shadow is the planet's, and it's a great clue about the spherical shape of the Earth.

Since the earth is rotating (see the " Foucault Pendulum " experiment for a definite proof, if you are doubtful), the consistent oval-shadow it produces in each and every lunar eclipse proves that the earth is not only round but spherical-absolutely, utterly, beyond a shadow of a doubt not flat.

2. Ships and the horizon

If you've been next to a port lately, or just strolled down a beach and stared off vacantly into the horizon, you might have noticed a very interesting phenomenon: Approaching ships do not just "appear" out of the horizon (like they should have if the world was flat), but rather seem to emerge from beneath the sea.

But-you say-ships do not submerge and rise up again as they approach our view (except in Pirates of the Caribbean, but we are hereby assuming that was a fictitious movie series). The reason ships appear as if they "emerge from the waves" is because the world is not flat: It's round.

Imagine an ant walking along the surface of an orange, into your field of view. If you look at the orange "head on", you will see the ant's body slowly rising up from the "horizon" because of the curvature of the orange. If you would do that experiment with the ant approaching along a long road rather than a round object, the effect would change: The ant would slowly "materialize" into view (depending on how sharp your vision is).

3. Varying star constellations

This observation was originally made by Aristotle (384-322 BCE), who declared the Earth was round judging from the different constellations one sees while moving away from the equator.

After returning from a trip to Egypt, Aristotle noted, "There are stars seen in Egypt and...Cyprus which are not seen in the northerly regions." This phenomenon can only be explained if humans were viewing the stars from a round surface, Aristotle continued, claiming that the sphere of the Earth is "of no great size, for otherwise the effect of so slight a change of place would not be quickly apparent." (De caelo, 298a2-10)

The farther you go from the equator, the farther the "known" constellations go towards the horizon, to be replaced by different stars. This would not have happened if the world was flat:

4. Shadows and sticks

If you stick a stick in the (sticky) ground, it will produce a shadow. The shadow moves as time passes (which is the principle for ancient Shadow Clocks). If the world had been flat, then two sticks in different locations would produce the same shadow:

But they don't. This is because the Earth is round, and not flat:

Eratosthenes (276-194 BCE) used this principle to calculate the circumference of the Earth quite accurately. To see this demonstrated, refer to my experiment video about Eratosthenes and the circumference of the Earth.

5. Seeing farther from higher

Standing on a flat plateau, you look ahead toward the horizon. You strain your eyes, then take out your favorite binoculars and stare through them, as far as your eyes (with the help of the binocular lenses) can see.

Next, climb up the closest tree-the higher the better, just be careful not to drop those binoculars and break their lenses. Then look again, strain your eyes, and stare through the binoculars out to the horizon.

The higher up you climb, the farther you will see. Usually, we tend to relate this to Earthly obstacles-like the fact we have houses or other trees obstructing our vision on the ground, and climbing upwards we have a clear view-but that's not the true reason. Even if you stood on a completely clear plateau with no obstacles between you and the horizon, you would see much farther from the greater height than you would on the ground.

This phenomenon is caused by the curvature of the Earth as well, and would not happen if the Earth was flat:

6. Ride a plane

If you've ever taken a trip out of the country, specifically long-distance trips, you could notice two interesting facts about planes and the Earth:

1. Planes can travel in a relatively straight line for a very long time and not fall off any edges. They can also circle the Earth without stopping.

2. If you look out the window on a trans-Atlantic flight, you can, most of the times, see the curvature of the Earth on the horizon. The best view of the curvature used to be on the Concorde, but that plane's long gone. I can't wait to see the pictures from the new plane by Virgin Galactic-the horizon should look absolutely curved, as it actually is from a distance.

7. Look at other planets

The Earth is different from other planets, that much is true. After all, we have life, and we haven't found any other planets with life (yet). However, there are certain characteristics all planets have, and it will be quite logical to assume that if all planets behave a certain way, or show certain characteristics-specifically if those planets are in different places or were created under different circumstances-our planet is the same.

In other words: If so many planets that were created in different locations and under different circumstances show the same property, it's likely that our own planet has the same property as well. All of our observations show that other planets are spherical (and since we know how they're created, it's also obvious why they take this shape). Unless we have a very good reason to think otherwise (which we don't), our planet is very likely the same.

In 1610, Galileo Galilei observed the moons of Jupiter rotating around it. He described them as small planets orbiting a larger planet-a description (and observation) that was very difficult for the church to accept, as it challenged a geocentric model where everything was supposed to revolve around the Earth. This observation also showed that the planets (Jupiter, Neptune, and later Venus was observed too) are all spherical, and all orbit the sun.

A flat planet (ours or any other planet) would be such an incredible observation that it would pretty much go against everything we know about how planets form and behave. It would not only change everything we know about planet formation, but also about star formation (our sun would have to behave quite differently to accommodate the flat-earth theory) and what we know of speeds and movements in space (like planets' orbits and the effects of gravity). In short, we don't just suspect that our planet is spherical. We know it.

8. The existence of time zones

The time in New York, at the moment these words are written, is 12:00pm. The sun is in the middle of the sky (though it's hard to see with the current cloud coverage). In Beijing, it's 12:00am, midnight, and the sun is nowhere to be found. In Adelaide, Australia, it is 1:30am. More than 13 hours ahead. There, the sunset is long gone-so much so, that the sun will soon rise up again at the beginning of a new day.

This can only be explained if the world is round, and rotating around its own axis. At a certain point when the sun is shining on one part of the Earth, the opposite side is dark, and vice versa. That allows for time differences and time zones, specifically ones that are larger than 12 hours.

Another point concerning timezones, the sun, and Earth: If the sun was a "spotlight" (very directionally located so that light only shines on a specific location) and the world was flat, we would see the sun even if it didn't shine on top of us (as you can see in the drawing below). Similarly, you can see the light coming out of a spotlight on a stage in the theater, even though you-the crowd-are sitting in the dark. The only way to create two distinctly separate time zones, where there is complete darkness in one while there's light in the other, is if the world is spherical.

9. The pull of gravity

Here's an interesting fact about mass: It attracts things to it. The force of attraction (gravity) between two objects depends on their mass and the distance between them. Simply said, gravity will pull toward the center of mass of the objects. To find the center of mass, you have to examine the object.

Consider a sphere. Since a sphere has a consistent shape, no matter where on it you stand, you have exactly the same amount of sphere under you. (Imagine an ant walking around on a crystal ball. From the insect's point of view, the only indication of movement would be the fact the ant is moving its feet-the shape of the surface would not change at all.) A sphere's center of mass is in the center of the sphere, which means gravity will pull anything on the surface of the sphere straight down toward the center of the sphere. This will occur no matter where on the surface the object is located.

Consider a flat plane. The center of mass of a flat plane is in its center, so the force of gravity will pull anything on the surface toward the middle of the plane. That means that if you stand on the edge of the plane, gravity will be pulling you sideways toward the plane's middle, not straight down like you usually experience when you stand on Earth.

I am quite positive that, even for Australians, an apple falls downwards, not sideways. But if you have your doubts, I urge you to try dropping something-just make sure it's nothing that can break or hurt you.

For further reading about the center of mass and distribution of mass, check out this link. And if you are brave enough to handle some equations (not involving integration), you can learn more about Newton's Law of Universal Gravitation here.

10. Images from space

In the past 60 years of space exploration, we've launched satellites, probes, and people into space. Some of them got back, some of them still float through the solar system (and almost beyond it), and many transmit amazing images to our receivers on Earth. In all of these photos, the Earth is (wait for it) spherical. The curvature of the Earth is also visible in the many, many, many, many photos snapped by astronauts aboard the International Space Station. You can see a recent example from ISS Commander Scott Kelly's Instagram right here:

You know what they say-a picture is worth a thousand diss tracks.
Moriel Schottlender is a software engineer at Wikimedia Foundation. This article was originally posted on her Smarter Than That blog in 2008.
You may also be interested in:

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10 easy ways you can tell for yourself that the Earth is not flat

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This story was originally published on Smarter Than That in 2008. We are republishing a lightly edited version on Popular Science in light of recent interest in the subject. Humanity has known Earth is round for a few millenia, and I've been meaning to show more methods that prove the world is not flat.

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Nuclear Bombs and Hydrogen Bombs

A discovery by nuclear physicists in a laboratory in Berlin, Germany, in 1938 made the first atomic bomb possible, after Otto Hahn, Lise Meitner and Fritz Strassman discovered nuclear fission.

In nuclear fission, the nucleus of an atom of radioactive material splits into two or more smaller nuclei, which causes a sudden, powerful release of energy. The discovery of nuclear fission opened up the possibility of nuclear technologies, including weapons.

Atomic bombs get their energy from fission reactions. Thermonuclear weapons, or hydrogen bombs, rely on a combination of nuclear fission and nuclear fusion. Nuclear fusion is another type of reaction in which two lighter atoms combine to release energy.

Manhattan Project

On December 28, 1942, President Franklin D. Roosevelt authorized the formation of the Manhattan Project to bring together various scientists and military officials working on nuclear research.

The Manhattan Project was the code name for the American-led effort to develop a functional atomic bomb during World War II. The project was started in response to fears that German scientists had been working on a weapon using nuclear technology since the 1930s.

Who Invented the Atomic Bomb?

Much of the work in the Manhattan Project was performed in Los Alamos, New Mexico, under the direction of theoretical physicist J. Robert Oppenheimer, the " father of the atomic bomb."

On July 16, 1945, in a remote desert location near Alamogordo, New Mexico, the first atomic bomb was successfully detonated-the Trinity Test. It created an enormous mushroom cloud some 40,000 feet high and ushered in the Atomic Age.

Hiroshima And Nagasaki Bombings

Scientists at Los Alamos had developed two distinct types of atomic bombs by 1945-a uranium-based design called "the Little Boy" and a plutonium-based weapon called "the Fat Man." (Uranium and plutonium are both radioactive elements.)

While the war in Europe had ended in April, fighting in the Pacific continued between Japanese forces and U.S. troops. In late July, President Harry Truman called for Japan's surrender with the Potsdam Declaration. The declaration promised "prompt and utter destruction" if Japan did not surrender.

On August 6, 1945, the United States dropped its first atomic bomb from a B-29 bomber plane called the Enola Gay over the city of Hiroshima, Japan. The "Little Boy" exploded with about 13 kilotons of force, leveling five square miles of the city and killing 80,000 people instantly. Tens of thousands more would later die from radiation exposure.

When the Japanese did not immediately surrender, the United States dropped a second atomic bomb three days later on the city of Nagasaki. The "Fat Man" killed an estimated 40,000 people on impact.

Nagasaki had not been the primary target for the second bomb. American bombers initially had targeted the city of Kokura, where Japan had one of its largest munitions plants, but smoke from firebombing raids obscured the sky over Kokura. American planes then turned toward their secondary target, Nagasaki.

Citing the devastating power of "a new and most cruel bomb," Japanese Emperor Hirohito announced his country's surrender on August 15-a day that became known as ' V-J Day '-ending World War II.

The Cold War

The United States was the only country with nuclear weaponry in the years immediately following World War II. The Soviet Union initially lacked the knowledge and raw materials to build nuclear warheads.

Within just a few years, however, the U.S.S.R. had obtained-through a network of spies engaging in international espionage-blueprints of a fission-style bomb and discovered regional sources of uranium in Eastern Europe. On August 29, 1949, the Soviets tested their first nuclear bomb.

The United States responded by launching a program in 1950 to develop more advanced thermonuclear weapons. The Cold War arms race had begun, and nuclear testing and research became high-profile goals for several countries, especially the United States and the Soviet Union.

Cuban Missile Crisis

Over the next few decades, each world superpower would stockpile tens of thousands of nuclear warheads. Other countries, including Great Britain, France, and China, developed nuclear weapons during this time, too.

To many observers, the world appeared on the brink of nuclear war in October of 1962. The Soviet Union had installed nuclear-armed missiles on Cuba, just 90 miles from U.S. shores. This resulted in a 13-day military and political standoff known as the Cuban Missile Crisis.

President John F. Kennedy enacted a naval blockade around Cuba and made it clear the United States was prepared to use military force if necessary to neutralize the perceived threat.

Disaster was avoided when the United States agreed to an offer made by Soviet leader Nikita Khrushchev to remove the Cuban missiles in exchange for the United States promising not to invade Cuba.

Three Mile Island

Many Americans became concerned about the health and environmental effects of nuclear fallout-the radiation left in the environment after a nuclear blast-in the wake of World War II and after extensive nuclear weapons testing in the Pacific during the 1940s and 1950s.

The antinuclear movement emerged as a social movement in 1961 at the height of the Cold War. During Women Strike for Peace demonstrations on November 1, 1961 co-organized by activist Bella Abzug, roughly 50,000 women marched in 60 cities in the United States to demonstrate against nuclear weapons.

The antinuclear movement captured national attention again in the 1970s and 1980s with high profile protests against nuclear reactors after the Three Mile Island accident-a nuclear meltdown at a Pennsylvania power plant in 1979.

In 1982, a million people marched in New York City protesting nuclear weapons and urging an end to the Cold War nuclear arms race. It was one of the largest political protests in United States history.

Nuclear Non-Proliferation Treaty (NPT)

The United States and Soviet Union took the lead in negotiating an international agreement to halt the further spread of nuclear weapons in 1968.

The Treaty on the Non-Proliferation of Nuclear Weapons (also called the Non-Proliferation Treaty or NPT) went into effect in 1970. It separated the world's countries into two groups-nuclear weapons states and non-nuclear weapons states.

Nuclear weapons states included the five countries that were known to possess nuclear weapons at the time-the United States, the U.S.S.R., Great Britain, France and China.

According to the treaty, nuclear weapons states agreed not to use nuclear weapons or help non-nuclear states acquire nuclear weapons. They also agreed to gradually reduce their stockpiles of nuclear weapons with the eventual goal of total disarmament. Non-nuclear weapons states agreed not to acquire or develop nuclear weapons.

When the Soviet Union collapsed in the early 1990s, there were still thousands of nuclear weapons scattered across Eastern Europe and Central Asia. Many of the weapons were located in Belarus, Kazakhstan and Ukraine. These weapons were deactivated and returned to Russia.

Illegal Nuclear Weapon States

Some countries wanted the option of developing their own nuclear weapons arsenal and never signed the NPT. India was the first country outside of the NPT to test a nuclear weapon in 1974.

Other non-signatories to the NTP include: Pakistan, Israel and South Sudan. Pakistan has a known nuclear weapons program. Israel is widely believed to possess nuclear weapons, though has never officially confirmed or denied the existence of a nuclear weapons program. South Sudan is not known or believed to possess nuclear weapons.

North Korea

North Korea initially signed the NPT treaty, but announced its withdrawal from the agreement in 2003. Since 2006, North Korea has openly tested nuclear weapons, drawing sanctions from various nations and international bodies.

North Korea tested two long-range intercontinental ballistic missiles in 2017-one reportedly capable of reaching the United States mainland. In September 2017, North Korea claimed it had tested a hydrogen bomb that could fit on top an intercontinental ballistic missile.

Iran, while a signatory of the NPT, has said it has the capability to initiate production of nuclear weapons at short notice.

Sources

Pioneering Nuclear Science: The Discovery of Nuclear Fission. International Atomic Energy Agency.
The Development and Proliferation of Nuclear Weapons. NobelPrize.org.
Here are the facts about North Korea's nuclear test. NPR.

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Atomic Bomb: Nuclear Bomb, Hiroshima & Nagasaki - HISTORY

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The atomic bomb and nuclear bombs, powerful weapons that use nuclear reactions as their source of explosive energy, are regulated by international agreements.

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iPhone XS. With an all-screen design. Super Retina display in two sizes. TrueDepth Camera. Face ID. Dual-camera system. And A12 Bionic chip.

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A certified medical assistant in Corpus Christi, Texas, prepares a Gardasil shot.

Credit: Matthew Busch for The Washington Post via Getty Images

The U.S. Food and Drug Administration announced last week that Gardasil 9, the HPV vaccine, is now approved for use in people ages 27 to 45.

The vaccine, which protects against several strains of a sexually transmitted infection called human papillomavirus, has been on the market for 12 years; however, it was approved only for people ages 9 to 26. New research led the agency to expand the age range to 45, the FDA said in an Oct. 5 statement.

But does the new age approval mean that adults who never got the HPV vaccine should get one now? Not necessarily. [ 51 Facts About Sex]

To understand why that might be the case, it's important to understand what the vaccine can and cannot do. Gardasil 9, which is the version offered in the U.S., protects people from nine strains of HPV, seven of which can cause cancer in the cervix, vagina, anus, penis and throat, and two of which can cause genital warts. (The original version of the vaccine, simply called Gardasil, protected against the warts strains and two of the strains linked to cancer, the FDA said.)

All told, the vaccine prevents over 90 percent of possible HPV-caused cancers, said Gypsyamber D'Souza, an epidemiologist at the Bloomberg School of Public Health at Johns Hopkins University.

But here's the catch: The vaccine only works if the recipient hasn't had HPV before. If someone has already been exposed to a given strain of HPV - which a majority of reproductive-age Americans already have, according to the Centers for Disease Control and Prevention - the vaccine can't clear that infection, D'Souza told Live Science.

Still, because the vaccine protects against nine strains, if an adult hasn't previously been exposed to some of the other strains in the vaccine, it could protect against future infection with those strains.

Most HPV infections, including potentially cancer-causing varieties, go away on their own, the National Cancer Institute says. But about 33,700 people are diagnosed with HPV-induced cancers each year, the CDC says. And for those individuals whose infection would cause cancer, getting the vaccine before becoming sexually active can prevent their HPV encounters from turning into an infection and, eventually, leading to cancer, D'Souza said. Indeed, that's why the FDA approval and vaccine recommendations focused on younger, potentially less sexually active people in the past.

Generally, adults ages 27 to 45 are expected to have already been exposed to HPV, D'Souza said, because they're more likely to be in monogamous, long-term sexual relationships. Of course, not everyone in this age group is having low-risk sex, and now they have the option of getting the HPV vaccine. With the new research and approval of Gardasil 9 in this age group, the FDA is saying that the drug can still prevent HPV infections in these adults, D'Souza said.

The FDA announcement means that "it's approved for them because it's safe and will allow them to get vaccinated if they so desire," D'Souza said. "But we're going to need to look to our [medical] organizations that make recommendations about prevention and disease screening to review the data and understand whether the vaccine should be widely recommended for the age group."

Vaccines of any kind can have emotional and, depending on insurance coverage, financial costs. And while the HPV vaccine will not cause any harm, D'Souza said, medical organizations won't make any official recommendations until they have ample data showing the benefits of the vaccine for the entire age group. (Some of the organizations that will weigh in include the such as the American Society for Colposcopy and Cervical Pathology and the U.S. Preventive Services Task Force.)

Editor's note: This story was updated on Oct. 10 to clarify that, if a person has already been exposed to a particularly strain of the HPV virus before being vaccinated, the vaccine won't protect against that strain. However, it will protect against strains the person hasn't been exposed to.

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The HPV Vaccine Was Just Approved for Adults Up to Age 45. Should They Get It?

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The U.S. Food and Drug Administration announced last week that Gardasil 9, the HPV vaccine, is now approved for use in people ages 27 to 45. The vaccine, which protects against several strains of a sexually transmitted infection called human papillomavirus, has been on the market for 12 years; however, it was approved only for people ages 9 to 26.

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The Cassini-Huygens mission has revolutionized our knowledge of the Saturn system and revealed surprising places in the solar system where life could potentially gain a foothold-bodies we call ocean worlds.

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A New Age in Human Evolution

By now, most of us know what CRISPR gene editing is. At the very least, we have heard of this revolutionary technology that allows us to alter DNA-the source code of life itself. One day, CRISPR could allow us to delete genes in order to eradicate genetic diseases, add in new genes in order to vastly improve various biological functions, or even genetically modify human embryos in order to create an entirely new class of humans...of super humans.

But first, we have a lot of research to do.

And that brings us to today. Reports from MIT were just released which assert that the very first attempt at creating genetically modified human embryos in the United States has been carried out by a team of researchers in Portland, Oregon.

"So far as I know this will be the first study reported in the U.S.," Jun Wu, who played a role in the project and is a collaborator at the Salk Institute, said to MIT.

According to MIT, the work was led by Shoukhrat Mitalipov, who comes from the Oregon Health and Science University. Although details are scarce at this point, sources familiar with the work assert that the research involved changing the DNA of one-cell embryos using CRISPR gene-editing. Further, Mitalipov is believed to have broken records in two notable ways:

1. He broke the record on the number of embryos experimented upon.

2. He is the first researcher to ever conclusively demonstrate that it is possible to safely and efficiently correct defective genes that cause inherited diseases.

This is notable because, despite the fact that it has been around for several years now, CRISPR is still an incredibly new tool-one that could have unintended consequences. As previous work published in the journal Nature Methods revealed, CRISPR-Cas9 could lead to unintended mutations in a genome. However, the work was later reviewed by researchers at another institution and the findings were brought into question. It remains to be seen whether the original study will be corrected or retracted, but this development highlights the importance of peer review in science.

In this regard, Mitalipov's work brings us further down the path to understanding exactly how CRISPR works in humans, and reveals that is it possible to avoid both mosaicism (changes that are taken up not by only some of the cells of an embryo, as opposed to all of them) and "off-target" effects.

A Long Road to Travel

It is important to note that none of the embryos were allowed to develop for more than a few days, and that the team never had any intention of implanting them into a womb. However, it seems that this is largely due to ongoing regulatory issues, as opposed to issues with the technology itself.

In the United States, all efforts to turn edited embryos into a baby-to bring the embryo to full term-have been blocked by Congress, which added language to the Department of Health and Human Services funding bill that forbids it from approving any such clinical trials.

Yet, the potential of the CRISPR-Cas9 system as a gene editing technology is undeniable. As previously mentioned, it has seen success in developing possible cancer treatments, in making animals disease-resistant, and it has even shown promise in replacing antibiotics altogether.

This new work adds to the promise of CRISPR, and stands as an important step toward the birth of the first genetically modified humans.

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BREAKING: Scientists Just Successfully Edited the First Human Embryo Ever in The U.S.

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By now, most of us know what CRISPR gene editing is. At the very least, we have heard of this revolutionary technology that allows us to alter DNA-the source code of life itself.

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Researchers from Keele University have worked with an international team of astronomers to find for the first time that a white dwarf and a brown dwarf collided in a 'blaze of glory' that was witnessed on Earth in 1670.

Using the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, the international team of astronomers, including workers from the Universities of Keele, Manchester, South Wales, Arizona State, Minnesota, Ohio State, Warmia & Mazury, and the South African Astronomical Observatory, found evidence that a white dwarf (the remains of a star like the Sun at the end of its life) and a brown dwarf (a 'failed' star without sufficient mass to sustain thermonuclear fusion) collided in a short-lived blaze of glory that was witnessed on Earth in 1670 as Nova Cygni -- 'a new star below the head of the Swan.' The brown dwarf star was 'shredded' and dumped on the surface of a white dwarf star, leading to the 1670 eruption and the hourglass we see today.

In July of 1670, observers on Earth witnessed a 'new star', or nova, in the constellation Cygnus -- the Swan. Where previously there was no obvious star, there abruptly appeared a star as bright as those in the Plough, that gradually faded, reappeared, and finally disappeared from view.

Modern astronomers studying the remains of this cosmic event initially thought it was triggered by the merging of two main-sequence stars -- stars on the same evolutionary path as our Sun. This so-called 'new star' was long referred to as 'Nova Vulpeculae 1670', and later became known as CK Vulpeculae.

However, we now know that CK Vulpeculae was not what we would today describe as a 'nova', but is in fact the merger of two stars -- a white dwarf and a brown dwarf.

By studying the debris from this explosion -- which takes the form of dual rings of dust and gas, resembling an hourglass with a compact central object -- the research team concluded that a brown dwarf, a so-called failed star without the mass to sustain nuclear fusion, had merged with a white dwarf.

Professor Nye Evans, Professor of Astrophysics at Keele University and co-author on the paper appearing in the Monthly Notices of the Royal Astronomical Society explains:

"CK Vulpeculae has in the past been regarded as the oldest 'old nova'. However, the observations of CK Vulpeculae I have made over the years, using telescopes on the ground and in space, convinced me more and more that this was no nova. Everyone knew what it wasn't -- but nobody knew what it was! But a stellar merger of some sort seemed the best bet. With our ALMA observations of the exquisite dusty hourglass and the warped disc, plus the presence of lithium and peculiar isotope abundances, the jig-saw all fitted together: in 1670 a brown dwarf star was 'shredded' and dumped on the surface of a white dwarf star, leading to the 1670 eruption and the hourglass we see today."

The team of European, American and South African astronomers used the Atacama Large Millimeter/submillimeter Array to examine the remains of the merger, with some interesting findings. By studying the light from two, more distant, stars as they shine through the dusty remains of the merger, the researchers were able to detect the tell-tale signature of the element lithium, which is easily destroyed in stellar interiors.

Dr Stewart Eyres, Deputy Dean of the Faculty of Computing, Engineering and Science at the University of South Wales and lead author on the paper explains:

"The material in the hourglass contains the element lithium, normally easily destroyed in stellar interiors. The presence of lithium, together with unusual isotopic ratios of the elements C, N, O, indicate that an (astronomically!) small amount of material, in the form of a brown dwarf star, crashed onto the surface of a white dwarf in 1670, leading to thermonuclear 'burning', an eruption that led to the brightening seen by the Carthusian monk Anthelme and the astronomer Hevelius, and in the hourglass we see today."

Professor Albert Zijlstra, from The University of Manchester's School of Physics & Astronomy, co-author of the study, says:

"Stellar collisions are the most violent events in the Universe. Most attention is given to collisions between neutrons stars, between two white dwarfs -- which can give a supernova -- and star-planet collisions.

"But it is very rare to actually see a collision, and where we believe one occurred, it is difficult to know what kind of stars collided. The type we believe that happened here is a new one, not previously considered or ever seen before. This is an extremely exciting discovery."

Professor Sumner Starrfield, Regents' Professor of Astrophysics at Arizona State University comments:

"The white dwarf would have been about 10 times more massive than the brown dwarf, so as the brown dwarf spiralled into the white dwarf it would have been ripped apart by the intense tidal forces exerted by the white dwarf. When these two objects collided, they spilled out a cocktail of molecules and unusual element isotopes.

"These organic molecules, which we could not only detect with ALMA, but also measure how they were expanding into the surrounding environment, provide compelling evidence of the true origin of this blast. This is the first time such an event has been conclusively identified.

"Intriguingly, the hourglass is also rich in organic molecules such as formaldehyde (H2CO), methanol (CH3OH) and methanamide (NH2CHO). These molecules would not survive in an environment undergoing nuclear fusion and must have been produced in the debris from the explosion. This lends further support to the conclusion that a brown dwarf met its demise in a star-on-star collision with a white dwarf."

Since most star systems in the Milky Way are binary, stellar collisions are not that rare, the astronomers note.

Professor Starrfield adds:

"Such collisions are probably not rare and this material will eventually become part of a new planetary system, implying that they may already contain the building-blocks of organic molecules as they are forming."

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stars; eris (xena); galaxies; extrasolar planets; origin of life; early climate; evolution; fossils

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When is a nova not a nova? When a white dwarf and a brown dwarf collide

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Researchers from Keele University have worked with an international team of astronomers to find for the first time that a white dwarf and a brown dwarf collided in a 'blaze of glory' that was witnessed on Earth in 1670.

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The northern eyewall of Hurricane Michael comes ashore between St. Vincent Island and Panama City, Florida, on Oct. 10, 2018.

Credit: NOAA

Forecasters watching Hurricane Michael barrel toward the Gulf coast of Florida earlier this week saw the storm do something "most unusual."

The hurricane intensified despite encountering wind shear -a change in wind speed or direction at different levels in the atmosphere-that might have normally weakened the storm.

"Michael's steady intensification over the past 48 hours in the face of 20-knot [23 mph] westerly shear defies traditional logic," hurricane specialist Stacy Stewart wrote in a memo from the National Hurricane Center on Monday (Oct. 8). "Either the shear calculations are unrepresentative or Michael has become more inertially stable due to its large eye and large outer wind field, making it more shear-resistant."

So how would forecasters typically expect wind shear to affect a storm? That's explained in part by the shape of a hurricane. [ Hurricane Season 2018: How Long It Lasts and What to Expect]

Other non-hurricane storm systems, such as Nor'easters that hit the mid-Atlantic, are driven by differences in temperature and take on a sloped shape in the atmosphere. The warmest parts of the storm closest to Earth's surface are usually out at the front of the system with the highest part trailing back usually to the west and northwest to where the cold air is.

Hurricanes, meanwhile, stretch from Earth's surface to the upper reaches of the atmosphere and each level of the storm needs to be stacked and working in coordination to help the massive system gain energy and grow in intensity.

"With a hurricane you can see the eye from outer space; it's more like a chimney," Joel Cline, Tropical Program Coordinator at NOAA's National Weather Service, told Live Science. "If the chimney's not perfectly straight, you can have the hottest fire -in other words, the warmest water -but the flame goes out."(Warm water fuels hurricanes.)

Wind shear could disrupt the hurricane, essentially tilting or breaking up the chimney, which would weaken the storm. But that didn't happen in Hurricane Michael's case.

"There was some available wind shear when it was near Cuba right before it went into the Gulf, and wind shear is one of the variables that will decrease the intensity of a storm," Marangelly Fuentes, a NASA atmospheric scientist, told Live Science. But the storm really intensified, going from a Category 1 to a Category 4 hurricane in a matter of 24 hours, once it went into the Gulf.

"You have to remember that Michael actually intensified to a Category 4 -almost 5 right now -after it was in the Gulf of Mexico where there was not that much shear," Fuentes said.

A lack of shear was just one of the factors that caused Michael to intensify, Fuentes explained. Sea-surface temperatures are warmer than average in the Gulf of Mexico right now, adding more fuel to the storm. A lack of friction from land also allowed Michael to keep gaining strength over the water.

The huge storm strengthened to a Category 4 hurricane overnight, packing winds up to 145 mph (230 km/h) as it approached the Florida Panhandle this morning.

"People get very fixated on the category numbers-it doesn'tmatter at this point," Kline said. In addition to the potentially deadly storm surge expected to hit parts of the Florida coast, the wind damage will be extensive near the eye of the storm, Kline said, and rainfall is a big concern, especially in areas that were lashed by Florence last month. "Because of what's happened [with Florence] in the recent past, there's a greater chance of flash floods."

And while a Category 4 storm might be unprecedented for the Florida Panhandle, Kline noted that major hurricanes are predicted to strike this part of the Florida coast about every 30 years, as a National Hurricane Center map shows.

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Why Did Hurricane Michael Become Such a Monster Storm So Quickly?

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Forecasters watching Hurricane Michael barrel toward the Gulf coast of Florida earlier this week saw the storm do something "most unusual." The hurricane intensified despite encountering wind shear -a change in wind speed or direction at different levels in the atmosphere-that might have normally weakened the storm.

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Hydrogen Finally Mega-Evolved

As reported back in September, two studies, each with a different approach, were attempting to created metallic hydrogen, and now, more than 80 years after it was predicted to be possible, the Harvard University team has finally managed to produce the elusive state. Physicists Isaac Silvera, who has been working on this problem for 45 years, and Ranga Dias published their study's results this week in the journal .

To develop metallic hydrogen, Silvera's team squeezed two opposing heavy-duty diamonds together to compress gaseous hydrogen, and then they transitioned it into its liquid state by lowering the temperature [hydrogen liquifies at a temperature of -252°C (-423°F)]. They then gradually increased the applied pressure on the solid hydrogen by twisting a steel screw to exert force on the diamond anvil. It was then that changes were noticed.

At about 2 million atmospheres (or 200 gigapascal), the hydrogen stayed transparent. It turned an opaque black at 4 million atmospheres, pressure levels greater than those found at the center of the Earth. Then, at around 4.95 million atmospheres, the hydrogen started to reflect 90 percent of light shone on it. This meant it had become metallic, a state of hydrogen that had never existed on our planet before. Silvera calls it "the holy grail of high-pressure physics."

This, of course, is no small feat. Transforming hydrogen gas into a metallic state, a phenomenon known as the Wigner-Huntington transition, was first predicted in 1935. Previous tests to bring this phenomenon to life had not been successful because diamonds would break under such extreme pressure, either due to flaws in the diamonds or the hydrogen itself diffusing into the crystalline lattice of the diamonds, causing them to break apart. To work around these problems, Silvera's team used a reactive ion etching technique to remove any nanoscale imperfections and created a diffusion barrier by coating the diamonds with a thin layer of alumina.

Simple But Powerful

Hydrogen, element number one on the periodic table, is the most basic atom, just one proton with one electron. However, it supposedly possesses incredible potential in its metallic form. For one thing, physicists predict that metallic hydrogen is an authentic superconductor. This gives metallic hydrogen a myriad of potential applications.

"Let's say you could make wires out of superconducting metallic hydrogen," Silvera speculated. "Then if you transport energy, you would have no dissipation because it doesn't have resistance. Right now, in our electrical grid we lose energy just by heating up the wire during transmission." Dias also believes it could lead to the creation of superconducting magnetic storage, which "maintains persistent currents in superconducting coils." This could be a useful tool for maintaining equilibrium in the power grid when using renewable sources like solar and wind, which produce electricity intermittently. Because it is expected to work both at room temperatures or higher, metallic hydrogen could replace the magnets currently used in MRI machines as well.

Another application, which Dias calls the "most romantic," would be "magnetic levitation of high-speed trains, based on the perfect diamagnetism of superconductors." This could revolutionize transportation, as magnetic levitation is used for high-speed systems like the Hyperloop. Then there's rocketry. A metallic state could make hydrogen "the most powerful rocket propellant known to man," Silvera explained, about four times as powerful as existing rocket propellants that use molecular hydrogen and liquid oxygen. When heated, metallic hydrogen changes back to molecular hydrogen, which could produce a great deal of efficiently packed energy. "It would revolutionize rocketry," he explained, "enabling you to explore the outer planets, to put rockets into orbit with a single stage, and lift large payloads." This is no doubt why NASA partly funded the team's research.

While this is all exciting and potentially technology-changing, the only metallic hydrogen on Earth today remains in Silvera's lab, in the diamond anvil under high pressure. The team has yet to see if metallic hydrogen could remain stable once that pressure is released, so for now, let's just celebrate the discovery and remain hopeful for the day that metallic hydrogen changes the world.

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Scientists Have Finally Created Metallic Hydrogen

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By applying 4.95 million atmospheres of pressure to liquid hydrogen, Harvard physicists have claimed they were able to make it metallic, a state of hydrogen that had never existed on Earth before. Physicists predict that metallic hydrogen is an authentic superconductor, so if stabilized, it could revolutionize everything from energy storage to rocketry.

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from research organizations

A new DNA tool created by Michigan State University can accurately predict people's height, and more importantly, could potentially assess their risk for serious illnesses, such as heart disease and cancer.

For the first time, the tool, or algorithm, builds predictors for human traits such as height, bone density and even the level of education a person might achieve, purely based on one's genome. But the applications may not stop there.

"While we have validated this tool for these three outcomes, we can now apply this method to predict other complex traits related to health risks such as heart disease, diabetes and breast cancer," said Stephen Hsu, lead investigator of the study and vice president for research and graduate studies at MSU. "This is only the beginning."

Further applications have the potential to dramatically advance the practice of precision health, which allows physicians to intervene as early as possible in patient care and prevent or delay illness.

The research, featured in the October issue of Genetics, analyzed the complete genetic makeup of nearly 500,000 adults in the United Kingdom using machine learning, where a computer learns from data.

In validation tests, the computer accurately predicted everyone's height within roughly an inch. While bone density and educational attainment predictors were not as precise, they were accurate enough to identify outlying individuals who were at risk of having very low bone density associated with osteoporosis or were at risk of struggling in school.

Traditional genetic testing typically looks for a specific change in a person's genes or chromosomes that can indicate a higher risk for diseases such as breast cancer. Hsu's model considers numerous genomic differences and builds a predictor based on the tens of thousands of variations.

Using data from the UK Biobank, an international resource for health information, Hsu and his team put the algorithm to work, evaluating each participant's DNA and teaching the computer to pull out these distinct differences.

"The algorithm looks at the genetic makeup and height of each person," Hsu said. "The computer learns from each person and ultimately produces a predictor that can determine how tall they are from their genome alone."

Hsu's team will continue to improve the algorithms, while tapping into larger, more diverse data sets. Doing this would further validate the techniques and continue to help map out the genetic architecture of these important traits and disease risks.

With greater computing power and decreasing costs around DNA sequencing, what was once thought to be five to 10 years out, is now a lot closer when it comes to this type of work, Hsu added.

"Our team believes this is the future of medicine," he said. "For the patient, a genomic test can be as simple as a cheek swab, with a cost of about $50. Once we calculate the predictors for genetically based diseases, early intervention can save billions of dollars in treatment costs, and more importantly, save lives."

Journal Reference:

Louis Lello, Steven G. Avery, Laurent Tellier, Ana I. Vazquez, Gustavo de los Campos, Stephen D. H. Hsu. Accurate Genomic Prediction of Human Height. Genetics, 2018; 210 (2): 477 DOI: 10.1534/genetics.118.301267

Cite This Page:

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personalized medicine; diseases and conditions; breast cancer; women's health; technology; organic chemistry; forensic research; microarrays

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New DNA tool predicts height, shows promise for serious illness assessment

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from research organizations A new DNA tool created by Michigan State University can accurately predict people's height, and more importantly, could potentially assess their risk for serious illnesses, such as heart disease and cancer.

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Galaxies abound in this spectacular Hubble image; spiral arms swirl in all colors and orientations.

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Researchers have discovered a huge chain of ancient, underwater volcanoes about 250 miles (400 kilometers) east of Tasmania. This sonar map shows some of the massive seamounts, beginning about 3 miles (5,000 meters) below the ocean's surface.

Credit: CSIRO

Thanks to an especially slobbery "Looney Tune," the island of Tasmania is best-known for its eponymous devils. But the nearby Tasman Sea is no less rich in oddball biodiversity. Take, for example, the newest discovery reported by the Australian research vessel the Investigator. A team of seafaring scientists has uncovered an ancient highway of massive underwater volcanoes - and those submerged mountains (or "seamounts") are apparently brimming with whales, according to a news release from Australia's national science agency. [ Infographic: Tallest Mountain to Deepest Ocean Trench]

"While we were over the chain of seamounts, the ship was visited by large numbers of humpback and long-finned pilot whales," Eric Woehler, a seabird ecologist at the University of Tasmania and a crewmember aboard the Investigator during its recent expedition, said in a statement. "We estimated that at least 28 individual humpback whales visited us on one day, followed by a pod of 60 to 80 long-finned pilot whales the next."

The research vessel crew spotted nearly 30 humpback whales near their boat in one day. It's possible that the massive, volcanic mountains nearby serve as underwater "signposts" that help the whales find their way to and from their breeding grounds.

Credit: ©Eric Woehler

Woehler and a crew of colleagues had recently embarked on a 25-day tourof the Tasman Sea to study ocean productivity - the process by which microscopic phytoplankton turn sunlight into the carbon that sustains entire ocean ecosystems. While Woehler surveyed the local marine life, other crewmembers scanned for signs of phytoplankton activity and mapped previously uncharted chunks of the ocean floor using a special sonar.

Once the Investigator had sailed about 250 miles (400 kilometers) east of Tasmania, the crew saw spikes in phytoplankton activity. Sonar scans revealed that the activity coincided with the appearance of a gargantuan chain of volcanic mountains submerged thousands of feet below the surface of the sea.

Sonar scans revealed that these hidden, underwater mountain ranges rose up from the seafloor beginning about 3 miles (5,000 meters) below the water's surface. The mounts varied in size and inclination; some were jagged peaks that stabbed up to 2 miles (3,000 m) above the seafloor, while others were vast, low plateaus. But each of the titanic hills and valleys likely formed many millennia ago as a result of ancient volcanic activity in the area, the researchers said.

Today, that variety of terrain likely provides habitats for a hugely diverse population of marine life. The jutting mounts could serve as underwater "signposts" on a migratory highway for regional whales, helping to guide them from their winter breeding grounds to their summer feeding grounds, Woehler said. In addition to the plentiful phytoplankton and whale sightings, the Investigator crew also reported seeing a significant variety of seabirds, including four species of albatrosses and petrels.

"This is a very diverse landscape and will undoubtedly be a biological hotspot that supports a dazzling array of marine life," said Tara Martin, a researcher with the Commonwealth Scientific and Industrial Research Organization (CSIRO), the Australian science agency that owns and operates the Investigator.

Researchers will have to study these newly discovered seamounts further to find out if they are indeed what Woehler called a "highway of marine life." Two fresh expeditions to the area are set to embark in November and December. In these trips, the team plans to bring back high-resolution video of the sea life swarming on and around the ancient seamounts. Stay tuned for the footage on the Investigator's website.

Originally published on Live Science.

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Lost Chain of Underwater Volcanoes Is a Massive Whale Superhighway

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Thanks to an especially slobbery "Looney Tune," the island of Tasmania is best-known for its eponymous devils. But the nearby Tasman Sea is no less rich in oddball biodiversity. Take, for example, the newest discovery reported by the Australian research vessel the Investigator.

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jeremy roos

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It doesn't happen often. But most summers, several Americans -- usually healthy, young people -- suffer sudden, tragic deaths from a brain-eating amoeba.

What is this scary bug? How does it get to the brain? Where is it and how can I avoid it? WebMD answers these and other questions.

How Do People Get Infected With Brain-Eating Amoeba?

The term " brain-eating amoeba" makes the amoeba sound like a tiny zombie stalking your skull. But brains are accidental food for them.

According to the CDC, N. fowleri normally eats bacteria. But when the amoeba gets into humans, it uses the brain as a food source.

How Long Until Symptoms of a Brain-Eating Amoeba Appear?

It takes two to 15 days for symptoms to appear after N. fowleri amoebas enter the nose. Death usually occurs three to seven days after symptoms appear. The average time to death is 5.3 days from symptom onset. Only a handful of patients worldwide have been reported to have survived an infection.

What Are the First Symptoms Someone Might Have?

Symptoms of PAM are not specific to this disease. At first, PAM may seem like viral meningitis. Symptoms include:

There may also be hallucinations, drooping eyelid, blurred vision, and loss of the sense of taste.

Is There a Treatment for Infection With Brain-Eating Amoeba?

The right treatment isn't clear. A number of drugs kill N. fowleri amoebas in the test tube. But even when treated with these drugs, very few patients survive.

Is There a Rapid Test for Infection With Brain-Eating Amoeba?

There is no rapid test for infection with brain-eating amoeba. But researchers are working to develop one. Until such tests come along, it can take weeks to identify the amoeba.

How Do Amoebas Dissolve Brain Tissue?

One study suggests that N. fowleri amoebas produce two proteases -- enzymes that dissolve protein.

Are Certain Groups Affected More Than Others?

Over 60% of U.S. cases are in children age 13 or younger. About 80% of cases are in males.

It's not at all clear whether children or males are more susceptible to the amoeba, or whether young males are more likely to engage in activities that expose them to the amoeba.

How Can I Protect Myself Against Brain-Eating Amoeba?

It makes sense to avoid swimming underwater, diving, water skiing, and jumping in warm, still waters during the late summer. It also makes sense to wear a nose clip when swimming, boating, or playing in or on warm waters.

It's also a good idea to avoid stirring up mud while taking part in such activities.

And if you are cleansing your nostrils, be sure to fill your neti pot or squeeze bottle with distilled or sterile water -- not tap water. You can also use water that has been boiled for one minute (three minutes at high elevations) and then cooled. And you can filter the water using filters with pores no larger than 1 micron (1 micrometer).

Continued

The nose is the pathway of the amoeba, so infection occurs most often from diving, water skiing, or performing water sports in which water is forced into the nose. But infections have occurred in people who dunked their heads in hot springs or who cleaned their nostrils with neti pots filled with untreated tap water.

A person infected with N. fowleri cannot spread the infection to another person.

How Do Amoebas Get in the Brain?

Studies suggest that N. fowleri amoebas are attracted to the chemicals that nerve cells use to communicate with one another. Once in the nose, the amoebas travel through the olfactory nerve (the nerve connected with sense of smell) into the frontal lobe of the brain.

How Frequently Do People Get Infected by a Brain-Eating Amoeba?

Even though N. fowleri amoebas are relatively common, they only rarely cause brain disease. N. fowleri disease is known as primary amoebic meningoencephalitis (PAM). It occurs from zero to eight times a year, almost always from July to September.

Continued

It's considered a rare infection. But some cases may be unreported. A study in Virginia that looked at more than 16,000 autopsy records from patients who died of meningitis found five previously unreported cases of PAM.

Studies show that many people may have antibodies to N. fowleri. That suggests that they became infected with the amoeba but that their immune systems fought it off.

It's not at all clear whether N. fowleri is a rare infection that always causes PAM and is almost always fatal, or a more common infection that only sometimes causes PAM.

In a 2009 study, CDC researchers suggested that the common finding of antibodies to the amoeba in humans and the frequent finding of N. fowleri in U.S. waters indicates "that exposure to the amoeba is much more common than the incidence of PAM suggests."

What Is a Brain-Eating Amoeba?

Amoebas are single-celled organisms. The so-called brain-eating amoeba is a species discovered in 1965. It's formal name is Naegleria fowleri. Although first identified in Australia, this amoeba is believed to have evolved in the U.S.

There are several species of Naegleria but only the fowleri species causes human disease. There are several fowleri subtypes. All are believed equally dangerous.

N. fowleri is microscopic: 8 micrometers to 15 micrometers in size, depending on its life stage and environment. By comparison, a hair is 40 to 50 micrometers wide.

Like other amoebas, Naegleria reproduces by cell division. When conditions aren't right, the amoebas become inactive cysts. When conditions are favorable, the cysts turn into trophozoites -- the feeding form of the amoeba.

Where Are Brain-Eating Amoebas Found?

Naegleria loves very warm water. It can survive in water as hot as 113 degrees Fahrenheit.

These amoebas can be found in warm places around the globe. N. fowleri is found in:

Warm lakes, ponds, and rock pits

Mud puddles

Warm, slow-flowing rivers, especially those with low water levels

Untreated swimming pools and spas

Untreated well water or untreated municipal water

Hot springs and other geothermal water sources

Thermally polluted water, such as runoff from power plants

Aquariums

Soil, including indoor dust

Naegleria can't live in salt water. It can't survive in properly treated swimming pools or in properly treated municipal water.

Most cases of N. fowleri disease occur in Southern or Southwestern states. Over half of all infections have been in Florida and Texas.

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Brain-Eating Amoeba (Naegleria Fowleri): FAQ, Symptoms, Treatment

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It doesn't happen often. But most summers, several Americans -- usually healthy, young people -- suffer sudden, tragic deaths from a brain-eating amoeba. What is this scary bug? How does it get to the brain? Where is it and how can I avoid it? WebMD answers these and other questions.

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Political humorist Mark Russell once joked, "The scientific theory I like best is that the rings of Saturn are composed entirely of lost airline luggage."

Well, there's no luggage, it turns out. But a new study appearing in Science based on data from the final orbits last year of NASA's Cassini spacecraft shows the rings of Saturn -- some of the most visually stupendous objects in the universe -- are far more chemically complicated than previously was understood.

Furthermore, the paper shows the innermost D ring of the gas giant is hurling dust grains coated in its chemical cocktail into the planet's upper atmosphere at an extraordinary rate as it spins. Over long timescales, the researchers say this infalling material may change the carbon and oxygen content of the atmosphere.

"This is a new element of how our solar system works," said Thomas Cravens, professor of physics & astronomy at the University of Kansas and a co-author of the new paper. "Two things surprised me. One is the chemical complexity of what was coming off the rings -- we thought it would be almost entirely water based on what we saw in the past. The second thing is the sheer quantity of it -- a lot more than we originally expected. The quality and quantity of the materials the rings are putting into the atmosphere surprised me."

Cravens is a member of Cassini's Ion and Neutral Mass Spectrometer (INMS) team. During Cassini's "Grand Finale" plunge into Saturn's innermost ring and upper atmosphere in 2017, the mass spectrometer aboard the probe sampled chemicals at altitudes between Saturn's rings and atmosphere.

More than simply water, the INMS found the rings to be composed of water, methane, ammonia, carbon monoxide, molecular nitrogen and carbon dioxide.

"What the paper is describing is the environment in the gap between the inner ring and upper atmosphere, and some of the things found were expected, such as water," Cravens said. "What was a surprise was the mass spectrometer saw methane -- no one expected that. Also, it saw some carbon dioxide, which was unexpected. The rings were thought to be entirely water. But the innermost rings are fairly contaminated, as it turns out, with organic material caught up in ice."

A further new finding from Cassini's mass spectrometer showed large amounts of the chemical brew from Saturn's D ring is flung into the planet's upper atmosphere by the ring spinning faster than the planet's atmosphere itself.

"We saw it was happening even though it's not fully understood," the KU researcher said. "What we saw is this material, including some benzine, was altering the uppermost atmosphere of Saturn in the equatorial region. There were both grains and dust that were contaminated."

Cravens said the findings could cast new light on mechanisms underpinning our solar system as well as other solar systems and exoplanets -- and also prompt a host of new scientific questions.

"This could help us understand, how does a planet get rings? Some do, some don't," he said. "What's the lifetime of a ring? And what's replenishing the rings? Was there a time when Saturn didn't have rings? How did that composition get into there in the first place? Is it left over from the formation of our solar system? Does it date back to proto pre-solar nebula, the nebula that collapsed out of interstellar media that formed the sun and planets?"

According to Cravens, the higher-than-expected rate of material being expelled from Saturn's D Ring into the planet's upper atmosphere, or ionosphere, is sufficient that astronomers now think the lifespan of the ring may be briefer than previously estimated.

"Because of this data, we now have shortened the lifetime of inner rings because of the quantity of material being moved out -- it's much more than we thought before," Cravens said. We know that it's bumping material out of the rings at least 10 times faster than we thought. If it's not being replenished, the rings aren't going to last -- you've got a hole in your bucket. Jupiter probably had a ring that evolved into the current wispy ring, and it could be for similar reasons. Rings do come and go. At some point they gradually drain away unless somehow they're getting new material."

Assisted by KU graduate and undergraduate students, a first stage of Cravens' work involved sorting and cleaning raw data from Cassini's INMS instrument.

"The raw data came through from our instrument on Cassini to deep-space antennas to NASA's Jet Propulsion Laboratory and then to computers at the Southwest Research Institute in San Antonio where Hunter Waite, the first author, is based," he said.

But Cravens' main contribution involved interpreting that data with a focus on how materials from the rings are altering Saturn's ionosphere. Cravens and his colleagues report the influx of chemicals from the rings change Saturn's equatorial ionospheric chemistry by converting the hydrogen ions and triatomic hydrogen ions into heavier molecular ions, depleting the planet's ionospheric density.

"My interest was in the ionosphere, the charged-particle environment, and that's what I focused on," Cravens said. "This gunk coming in chews up a lot of the ionosphere, affects its composition and causes observable effects -- that's what we're trying to understand now. The data are clear, but explanations are still being modeled and that will take a while. The material is coming into Saturn at high speeds because the rings are moving faster than the atmosphere quite a bit. It doesn't just drop in gently. It comes flying in there like a satellite re-entering our own planet. These dust grains moving at satellite speed, depositing energy that can dissociate the atmosphere. Per atom, it's pretty energetic stuff because of the speed differentiation between the rings and the atmosphere. We think it may be heating the upper atmosphere, changing its composition."

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saturn; solar system; astronomy; mars; extrasolar planets; space probes; astrophysics; pluto

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Surprising chemical complexity of Saturn's rings changing planet's upper atmosphere

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A new study based on data from the final orbits last year of NASA's Cassini spacecraft shows the rings of Saturn -- some of the most visually stupendous objects in the universe -- are far more chemically complicated than previously was understood.

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Newton's theory of "Universal Gravitation"

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How Newton related the motion of the moon to the gravitational acceleration g; part of an educational web site on astronomy, mechanics, and space

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Which species scare you most? Wild animals or insects. Wild animals would be your answer. But, do you know many insect stings can cause many deadly diseases. Without proper treatment, some insect bites may even result in death. Here is the list of 10 most dangerous insects in the world.

10 Bullet Ant

Bullet ant is the largest of all ants in the world. They mostly found in rainforests of Nicaragua and Paraguay. Bullet ants named after their painful sting. After the bite victim would feel like being shot. In fact, the sting by a bullet ant is 30 times more painful than of a wasp or a honey bee.

The one-inch sized bullet ant also called as '24-hour ant' by locals. It is because one full day pain followed by its sting. Each bullet ant colonies contain hundreds of members. They usually make a nest at the base of large trees. Bullet ants also release unpleasant odor once they found any predator. If that trick didn't drive the predators away, they would attack together with the powerful sting.

The larvae of botflies are internal parasites of mammals. Unfortunately, the dangerous larvae also live beneath human's skin and cause horrible effects. The human bot flies mostly found across Central and South America. 'Myiasis' known parasite infestation makes severe changes in skin tissues.

The young female bot flies laid eggs within the skin of mammals. The larvae penetrate through skin and lives in subdermal zones of human skin for more than 60 days. The patients could feel the movement of larvae beneath their skin. Once larvae development gets complete, it leaves out of the body.

Fleas are external parasites that suck blood from humans, birds, reptiles and wild and domestic animals. The fleas could cause itching spots on the skin of hosts. Fleas only have a size of the tip of a pen and reproduce very quickly. Every female flea lay 2000 eggs within their life span.

There are 2000 known species of flies in the world. Young fleas can consume the volume of blood that over 15 times their body weight. The flea bites on human body result in red bumps. They commonly found around waist, knees, and elbows. The bite of fleas are very itchy, and it may also lead to infection.

There are 285 different species of fire ants in the world. Once disturbed, they would sting the intruder repeatedly. The fire ant sting is very painful also. A white pustule caused by fire ant sting last for weeks. Their venom also would cause several skin problems. Fire ants usually attack in the group that contains ten to hundreds of ants. The venom of fire ants also result in allergic reaction

6 Kissing Bug

Kissing bugs grow up by sucking the blood of vertebrates. Kissing bugs named after their habit of biting the lip of human while they sleep. They also transmit parasite called as Trypanosoma cruzi. The kissing bug disease or 'changas' kills 12000 people every year.

The changa disease spread to animals and pets in the same way. The kissing bug bite results in instant changes within victim's body such as welts and rashes.

5 Giant Japanese Hornet

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Giant Japanese hornet is the largest species of hornet in the world. They grow up to a size of 2 inches. Every year up to 40 deaths are recorded by the sting of Japanese hornet. The venom of Japanese Hornet would cause an allergic reaction and dissolve tissues within the short time. The repeated stinging from the group of Hornets could also result in death.

Japanese hornets are very aggressive and fearless. Each colony of Japanese Hornet contains up to 700 members. They feed on honey bee larvae to a significant amount. They have the power to finish up to 40 honey bees in a minute.

4 Tsetse Flies

TseTse flies is a deadliest biting insect native to Africa. They mainly feed on the blood of vertebrates. The extreme dangerous insects inject potent toxin on each string. It is estimated that about half a million people lost their life by the attack of tsetse flies in Africa. At the primary stage, the venom of tsetse flies would make sleeping sickness on the victim. But it may lead to fatality without proper treatment.

3 Killer Bees

Killer bees also are known as Africanized honey bees. It is one of the very aggressive and dominant insects in the world. The group of killer bees follows the victim for more than 1 miles. They attacked in the group and made repetitive stinging.

The killer bees mainly target the face and eyes of humans. Their toxin is not so dangerous. But an attack by a group of killer bees could cause even death. They live within large colonies that contain more than 80000 members. Once they get disturbed, the bees become alerted for next 24 hours and would attack any animals or humans that come within their range.

2 Driver Ants

Driver ant has the largest colony than any other insects in the world. Each colony of driver ants has members up to 22 million. Even elephants would run away from the group attack of driver ants. They try to finish off any animal that comes across their path.

Driver ants typically kill thousands of different animals within a single raid. They make repetitive wounds on animals and humans using their strong mandibles. Driver ants also raid nests of other insects for food and kill them

Related Articles

1 Mosquitoes

Mosquitoes are most dangerous insect species on Earth. This deadliest insect causes 1 million death every year by transmitting deadly malaria disease. Mosquitoes carry malaria germs from one place to another, and they spread germs into the blood of victim by biting. WHO estimated that in every 30 seconds a child dies due to malaria and 500 million cases of malaria reported every year.

Malaria is a blood transmitting disease. This disease won't affect by contact with the sick person. It transmitted through parasites, mainly by bites of mosquitoes. In addition to malaria mosquitoes also spreads dengue fever, yellow fever, encephalitis and West Nile virus.

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Top 10 Deadliest Insects In The World - The Mysterious World

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Which species scare you most? Wild animals or insects. Wild animals would be your answer. But, do you know many insect stings can cause many deadly diseases. Without proper treatment, some insect bites may even result in death. Here is the list of 10 most dangerous insects in the world.

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Sharing meat after hunting and exchanging other valued food items is considered key in the evolution of cooperation in human societies. One prominent idea is that humans share valuable foods to gain future favors, such that those we chose to share with are more likely to cooperate with us in the future. Despite regularly occurring in humans, sharing food outside of kinship or mating relationships is rare in non-human animals. Our two closest living relatives, chimpanzees and bonobos, are two of the rare exceptions, and because of the important role of food sharing in human evolution, examining the sharing patterns of chimpanzees can help to answer questions on how sharing food amongst adults evolved and how it may have shaped human cooperation.

Researchers from the MPI-EVA observed natural food sharing behavior of the chimpanzees of the Tai National Park, Ivory Coast, and found that chimpanzees are very selective in who they share desirable food items, like meat, honey or large fruits, with. They show that chimpanzees were more likely to share food with their friends, and that neither high dominance status nor harassment by beggars influenced their decision. This complements results from another study by the same team published last month that examined meat sharing after group hunting of monkeys. There they found that chimpanzees in possession of meat after successful hunts were likely to reward other hunters by sharing with them. "Collectively our research shows that the chimpanzees decide when to share food based on the likelihood that this favor will be returned in the future," says Liran Samuni, first author of both studies. "Or, in case of sharing after group hunts, sharing of meat is returning the favor for helping out."

Previous studies in another subspecies of chimpanzees have suggested that food sharing in chimpanzees mainly occurs because of harassment pressure from beggars. "This was not the case for the Tai chimpanzees," Catherine Crockford, senior author on the studies, points out, "emphasizing the high variation in cooperation across chimpanzee populations." Human populations also vary in how cooperative they are and research is ongoing in both humans and non-human animals assessing what might make some populations more cooperative than others. "The need to stay in a cohesive unit, because of high predation pressure, or the capability to exhibit strong cohesion, because of rich food sources, are two possible scenarios to promote the expression of cooperative acts," suggests Roman Wittig, the second senior author of the studies.

Additionally, the researchers collected urine samples from chimpanzees after hunting and food sharing events and measured the hormone oxytocin. "We know that oxytocin plays a strong role in lactation, which you could look at as an example of food sharing between mother and infant, and is generally involved in social behavior and bonding," Liran Samuni explains. The researchers found high levels of oxytocin after chimpanzees shared meat and other valued foods, and after chimpanzee participated in hunting with others. "That we found higher oxytocin levels after both hunting and sharing adds to the idea that oxytocin is a key hormone involved in cooperation in general," Liran Samuni points out.

The researchers conclude that like humans, Tai chimpanzee sharing is selective, and that friends and others that helped acquiring the food benefit more. Emotional connection, as is obvious amongst friends, likely played a crucial role in the evolution of human cooperation.

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apes; food; food and agriculture; agriculture and food; nature; evolutionary biology; bacteria; endangered animals

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Wild chimpanzees share food with their friends

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Why share food with non-family members when there is no immediate gain? An international team of researchers conducted observations of natural food sharing behavior of the chimpanzees of the Tai National Park, Ivory Coast.

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(Image credit: MARK GARLICK/SCIENCE PHOTO LIBRARY via Getty Images)

The order of the planets in the solar system, starting nearest the sun and working outward is the following: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and then the possible Planet Nine.

The solar system extends from the sun, goes past the four inner planets, through the asteroid belt to the four gas giants and on to the disk-shaped Kuiper Belt and far beyond to the teardrop-shaped heliopause.

Scientists estimate that the edge of the solar system is about 9 billion miles (15 billion kilometers) from the sun. Beyond the heliopause lies the giant, spherical Oort Cloud, which is thought to surround the solar system.
Related: 10 incredible volcanoes in our solar system
Ever since the discovery of Pluto in 1930, kids grew up learning that the solar system has nine planets. That all changed in the late 1990s when astronomers started arguing about whether Pluto was indeed a planet. In a highly controversial decision, the International Astronomical Union ultimately decided in 2006 to designate Pluto as a "dwarf planet," reducing the list of the solar system's true planets to just eight.

If you insist on including Pluto, it would come after Neptune on the list. Pluto is truly way out there and on a wildly tilted, elliptical orbit (two of the several reasons it was demoted).
Related: 15 stunning places on Earth that look like they're from another planet
Astronomers, however, are still hunting for another possible planet in our solar system, a true ninth planet, after mathematical evidence of its existence was revealed on Jan. 20, 2016. The alleged "Planet Nine," also called "Planet X," is believed to be about 10 times the mass of Earth and 5,000 times the mass of Pluto.

Types of planets in the solar system

The inner four planets closest to the sun - Mercury, Venus, Earth and Mars - are often called the " terrestrial planets" because their surfaces are rocky. Pluto also has a rocky, albeit frozen, surface but has never been grouped with the four terrestrials.

The four large outer worlds - Jupiter, Saturn, Uranus and Neptune - are sometimes called the Jovian or "Jupiter-like" planets because of their enormous size relative to the terrestrial planets. They're also mostly made of gases like hydrogen, helium and ammonia rather than of rocky surfaces, although astronomers believe some or all of them may have solid cores.

Jupiter and Saturn are sometimes called the gas giants, whereas the more distant Uranus and Neptune have been nicknamed the ice giants. This is because Uranus and Neptune have more atmospheric water and other ice-forming molecules, such as methane, hydrogen sulfide and phosphene, that crystallize into clouds in the planets' frigid conditions, according to the Planetary Society. For perspective, methane crystallizes at minus 296 Fahrenheit (minus 183 degrees Celsius), according to the U.S. National Library of Medicine.

Solar system FAQs answered by an expert

We asked Maximilian Guenther, ESA Project Scientist and mission representative of ESA's Characterising Exoplanet Satellite (CHEOPS) mission a few frequently asked questions about solar systems.

What is (and isn't) a planet?

The IAU defines a true planet as a body that circles the sun without being some other object's satellite; is large enough to be rounded by its own gravity (but not so big that it begins to undergo nuclear fusion, like a star); and has "cleared its neighborhood" of most other orbiting bodies.

But that restrictive definition helped isolate what should and should not be considered a planet - a problem that arose as astronomers discovered more and more planet-like objects in the solar system. Pluto was among the bodies that didn't make the cut and was re-classified as a dwarf planet.

The problem with Pluto, aside from its small size and offbeat orbit, is that it doesn't clear its neighborhood of debris - it shares its space with lots of other objects in the Kuiper Belt. Still, the demotion of Pluto remains controversial.

The IAU planet definition also put other small, round worlds into the dwarf planet category, including the Kuiper Belt objects Eris, Haumea and Makemake.

Ceres, a round object in the Asteroid Belt between Mars and Jupiter, also got the boot. Ceres was considered a planet when it was discovered in 1801, but it was later deemed to be an asteroid. That still didn't quite fit because it was so much larger (and rounder) than the other asteroids. Astronomers instead deemed it a dwarf planet in 2006, although some astronomers like to consider Ceres as a 10th planet (not to be confused with Nibiru or Planet X).

Below is a brief overview of the eight true planets in our solar system, moving from that closest to the sun to the farthest from the sun:
Related: Solar eclipses 2023: When, where & how to see them
The sun is by far the largest object in our solar system, containing 99.8% of the solar system's mass. It sheds most of the heat and light that makes life possible on Earth and possibly elsewhere. Planets orbit the sun in oval-shaped paths called ellipses, with the sun slightly off-center of each ellipse.

NASA has a fleet of spacecraft observing the sun, such as the Parker Solar Probe, to learn more about its composition, and to make better predictions about space weather and its effect on Earth.

Mercury: The closest planet to the sun

Mercury is the closest planet to the sun and the smallest planet in the solar system - it is only a little larger than Earth's moon. Mercury zips around the sun in only 88 days and because it is so close to our star (about two-fifths the distance between Earth and the sun).

Mercury experiences dramatic changes in its day and night temperatures. Mercury temperatures can reach a scorching 840 F (450 C) in the day, which is hot enough to melt lead. Meanwhile, on the night side, temperatures drop to minus 290 F (minus 180 C).

- Diameter: 3,031 miles (4,878 km)

Mercury's atmosphere is very thin and primarily composed of oxygen, sodium, hydrogen, helium and potassium. Because the atmosphere is so thin it cannot incoming meteors, its surface is therefore pockmarked with craters, just like our moon.

Over its four-year mission, NASA's MESSENGER spacecraft revealed incredible discoveries that challenged astronomers' expectations. Among those findings was the discovery of water ice and frozen organic compounds at Mercury's north pole and that volcanism played a major role in shaping the planet's surface.

Related: How was Mercury formed?

Venus: Earth's solar system twin

Venus is the second planet from the sun and is the hottest planet in the solar system. Its thick atmosphere is extremely toxic and composed of sulfuric acid clouds, the planet is an extreme example of the greenhouse effect.

The average temperature on Venus' surface is 900 F (465 C). At 92 bar, the pressure at the surface would crush and kill you. And oddly, Venus spins slowly from east to west, the opposite direction of most of the other planets.

Venus is sometimes referred to as Earth's twin as they are similar in size and radar images beneath its atmosphere reveal numerous mountains and volcanoes. But beyond that, the planets could not be more different.

The Greeks believed Venus was two different objects - one in the morning sky and another in the evening. Because it is often brighter than any other object in the sky, Venus has generated many UFO reports.

Related: How was Venus formed?

Earth: Our home planet, filled with life

Earth, our home planet, is the third planet from the sun. It is a water world with two-thirds of the planet covered by water. Earth's atmosphere is rich in nitrogen and oxygen and it is the only world known to harbor life.

- Diameter: 7,926 miles (12,760 km)

- Orbit: 365.24 days

- Day: 23 hours, 56 minutes

- Number of moons: 1

Earth rotates on its axis at 1,532 feet per second (467 meters per second) - slightly more than 1,000 mph (1,600 kph) - at the equator. The planet zips around the sun at more than 18 miles per second (29 km per second).

Related: 10 Earth impact craters you must see

Mars: The solar system's Red Planet

Mars is the fourth planet from the sun. It is a cold, desert-like planet covered in iron oxide dust that gives the planet its signature red hue. Mars shares similarities with Earth: It is rocky, has mountains, valleys and canyons, and storm systems ranging from localized tornado-like dust devils to planet-engulfing dust storms.

Substantial scientific evidence suggests that Mars at one point billions of years ago was a much warmer, wetter world, rivers and maybe even oceans existed. Although Mars' atmosphere is too thin for liquid water to exist on the surface for any length of time, remnants of that wetter Mars still exist today. Sheets of water ice the size of California lie beneath Mars' surface, and at both poles are ice caps made in part of frozen water.

- Diameter: 4,217 miles (6,787 km)

- Number of moons: 2

Scientists also think ancient Mars would have had the conditions to support life like bacteria and other microbes. Hope that signs of this past life - and the possibility of even current lifeforms - may exist on the Red Planet has driven numerous Mars missions and the Red Planet is now one of the most explored planets in the solar system.

Related: How long does it take to get to Mars?

The asteroid belt

Between Mars and Jupiter lies the asteroid belt. Asteroids are minor planets, and according to NASA there are approximately between 1.1 and 1.9 million asteroids in the main asteroid belt larger than 0.6 miles (1 km) in diameter and millions more smaller asteroids.

The dwarf planet Ceres, about 590 miles (950 km) in diameter, resides here. A number of asteroids have orbits that take them closer into the solar system that sometimes lead them to collide with Earth or the other inner planets.

Jupiter: The largest planet in our solar system

Jupiter is the fifth planet from the sun and the largest planet in the solar system. The gas giant is more than twice as massive as all the other planets combined, according to NASA.

Its swirling clouds are colorful due to different types of trace gases including ammonia ice, ammonium hydrosulfide crystals as well as water ice and vapor.

A famous feature in its swirling clouds is Jupiter's Great Red Spot, a giant storm more than 10,000 miles wide, first observed in 1831 by amateur astronomer Samuel Heinrich Schwabe. It has raged at more than 400 mph for the last 150 years, at least.

Jupiter has a strong magnetic field, and with 75 moons, including the largest moon in the solar system, Ganymede.

Related: Jupiter's moons: Facts about the largest Jovian moons

Saturn: The ringed jewel of the solar system
Related: How far away is Saturn?
Saturn is the sixth planet from the sun and is famous for its large and distinct ring system. Though Saturn is not the only planet in the solar system with rings.

When polymath Galileo Galilei first studied Saturn in the early 1600s, he thought it was an object with three parts: a planet and two large moons on either side. Not knowing he was seeing a planet with rings, the stumped astronomer entered a small drawing - a symbol with one large circle and two smaller ones - in his notebook, as a noun in a sentence describing his discovery. More than 40 years later, Christiaan Huygens proposed that they were rings.

The rings are made of ice and rock and scientists are not yet sure how they formed. The gaseous planet is mostly hydrogen and helium and has numerous moons.

Uranus: The tilted, sideways planet in our solar system

Uranus is the seventh planet from the sun and is a bit of an oddball.

It has clouds made of hydrogen sulfide, the same chemical that makes rotten eggs smell so foul. It rotates from east to west like Venus. But unlike Venus or any other planet, its equator is nearly at right angles to its orbit - it basically orbits on its side.

- Diameter: 31,763 miles (51,120 km)

- Orbit: 84 Earth years

- Day: 18 Earth hours
Related: How did Uranus form?
- Number of moons: 27

Astronomers believe an object twice the size of Earth collided with Uranus roughly 4 billion years ago, causing Uranus to tilt. That tilt causes extreme seasons that last 20-plus years, and the sun beats down on one pole or the other for 84 Earth-years at a time.

The collision is also thought to have knocked rock and ice into Uranus' orbit. These later became some of the planet's 27 moons. Methane in Uranus' atmosphere gives the planet its blue-green tint. It also has 13 sets of faint rings.

Uranus holds the record for the coldest temperature ever measured in the solar system - minus 371.56 degrees F (minus 224.2 degrees C). The average temperature of Uranus is minus 320 degrees Fahrenheit (-195 degrees Celsius).

Neptune: A giant, stormy blue planet

Neptune is the eighth planet from the sun and is on average the coldest planet in the solar system. The average temperature of Neptune at the top of the clouds is minus 346 degrees Fahrenheit (minus 210 degrees Celsius).

Neptune is approximately the same size as Uranus and is known for its supersonic strong winds. The planet is more than 30 times as far from the sun as Earth.

Neptune was the first planet predicted to exist by using math, rather than being visually detected. Irregularities in the orbit of Uranus led French astronomer Alexis Bouvard to suggest some other planet might be exerting a gravitational tug. German astronomer Johann Galle used calculations to help find Neptune in a telescope. Neptune is about 17 times as massive as Earth and has a rocky core.

Related: There's something strange going on inside Neptune

Trans-Neptunian region

Astronomers had long suspected that a band of icy material known as the Kuiper Belt existed past the orbit of Neptune extending from about 30 to 55 times the distance of Earth to the sun, and from the last decade of the 20th century up to now, they have found more than a thousand of such objects. Scientists estimate the Kuiper Belt is likely home to hundreds of thousands of icy bodies larger than 60 miles (100 km) wide, as well as an estimated trillion or more comets.

Pluto, now considered a dwarf planet, dwells in the Kuiper Belt. It is not alone - recent additions include Makemake, Haumea and Eris. Another Kuiper Belt object dubbed Quaoar is probably massive enough to be considered a dwarf planet, but it has not been classified as such yet. Sedna, which is about three-fourths the size of Pluto, is the first dwarf planet discovered in the Oort Cloud. NASA's New Horizons mission performed history's first flyby of the Pluto system on July 14, 2015.

Pluto: Once a planet, now a dwarf planet

Pluto was once the ninth planet from the sun and is unlike any other planet in the solar system.

It is smaller than Earth's moon; its orbit is highly elliptical, falling inside Neptune's orbit at some points and far beyond it at others; and Pluto's orbit doesn't fall on the same plane as all the other planets - instead, it orbits 17.1 degrees above or below.

It is smaller than Earth's moon; its orbit is highly elliptical, falling inside Neptune's orbit at some points and far beyond it at others; and Pluto's orbit doesn't fall on the same plane as all the other planets - instead, it orbits 17.1 degrees above or below, taking 288 years to complete a single orbit according to ESA.

From 1979 until early 1999, Pluto had been the eighth planet from the sun. Then, on Feb. 11, 1999, it crossed Neptune's path and once again became the solar system's most distant planet - until it was redefined as a dwarf planet. It's a cold, rocky world with a tenuous atmosphere.

Scientists thought it might be nothing more than a hunk of rock on the outskirts of the solar system. But when NASA's New Horizons mission performed history's first flyby of the Pluto system on July 14, 2015, it transformed scientists' view of Pluto.

Pluto is a very active ice world that's covered in glaciers, mountains of ice water, icy dunes and possibly even cryovolcanoes that erupt icy lava made of water, methane or ammonia.

Related: Why isn't Pluto a planet anymore?

Planet Nine: A planet search at solar system's edge

In 2016, researchers proposed the possible existence of a ninth planet, for now, dubbed "Planet Nine" or Planet X. The planet is estimated to be about 10 times the mass of Earth and to orbit the sun between 300 and 1,000 times farther than the orbit of the Earth.

Scientists have not seen Planet Nine. They inferred its existence by its gravitational effects on other objects in the Kuiper Belt, a region at the fringe of the solar system that is home to icy rocks left over from the birth of the solar system. Also called trans-Neptunian objects, these Kuiper Belt objects have highly elliptical or oval orbits that align in the same direction.

Scientists Mike Brown and Konstantin Batygin at the California Institute of Technology in Pasadena described the evidence for Planet Nine in a study published in the Astronomical Journal. The research is based on mathematical models and computer simulations using observations of six other smaller Kuiper Belt Objects with orbits that aligned in a similar matter.

A hypothesis proposed in September 2019 on the pre-print server arXiv suggests Planet Nine might not be a planet at all. Instead, Jaku Scholtz of Durham University and James Unwin of the University of Illinois at Chicago speculate it could be a primordial black hole that formed soon after the Big Bang and that our solar system later captured, according to Newsweek. Unlike black holes that form from the collapse of giant stars, primordial black holes are thought to have formed from gravitational perturbations less than a second after the Big Bang, and this one would be so small (5 centimeters in diameter) that it would be challenging to detect.

Astronomers continue to come up empty in their search for Planet 9. A recent 2022 sky survey using the 6-meter Atacama Cosmology Telescope (ACT) in Chile found thousands of tentative candidate sources but none could be confirmed.

Related: The nonexistent planet Nibiru

The edge of the solar system

Past the Kuiper Belt is the very edge of the solar system, the heliosphere, a vast, teardrop-shaped region of space containing electrically charged particles given off by the sun. Many astronomers think that the limit of the heliosphere, known as the heliopause, is about 9 billion miles (15 billion km) from the sun.

The Oort Cloud lies well past the Kuiper Belt, considered to be located between 2,000 and 5,000 astronomical units (AU) from the sun. The outer edge of the Oort Cloud may reach as far as 10,000 up to 100,000 AU from the sun. One AU is equal to approximately 93,000,000 miles (150 million kilometers). The Oort Cloud is home to billions, or even trillions of objects, according to NASA Science.

Solar system formation and discovery

Approximately 4.5 billion years ago a dark cloud of gas and dust began to collapse. As it shrank, the cloud flattened into a swirling disk known as a solar nebula, according to NASA Science.

The heat and pressure eventually became so high that hydrogen atoms began to combine to form helium. The nuclear reactions released vast amounts of energy and our sun was formed.

The sun accumulated about 99% of the available matter and the remaining material further from the sun formed smaller clumps inside the spinning disk. Some of these clumps gained enough mass that their gravity shaped them into spheres, becoming planets, dwarf planets and moons. Other leftover pieces became asteroids, comets and smaller moons that make up our solar system.

Read more: How did the solar system form?

For millennia, astronomers have followed points of light that seemed to move among the stars. The ancient Greeks named them planets, meaning "wanderers." Mercury, Venus, Mars, Jupiter and Saturn were known in antiquity, and the invention of the telescope added the Asteroid Belt, Uranus, Neptune, Pluto and many of these worlds' moons. The dawn of the space age saw dozens of probes launched to explore our system, an adventure that continues today.
NASA solar system exploration
There have been five human-made objects so far, Voyager 1, Voyager 2, New Horizons, Pioneer 10 and Pioneer 11, that have crossed the threshold into interstellar space.

Related: How much of the solar system is made of interstellar stuff?

Additional resources

Explore the solar system in greater detail with these interactive resources from NASA. Discover the wonders of the solar system with this educational material from ESA. See where the planets are in their current orbit of the sun with this interactive orrery from NASA.

Bibliography

Prialnik, Dina K., Antonella Barucci, and Leslie Young, eds. The Trans-Neptunian Solar System. Elsevier, 2019.

Pirani, Simona, et al. " Consequences of planetary migration on the minor bodies of the early solar system." Astronomy & Astrophysics 623 (2019): A169.

Scholtz, Jakub, and James Unwin. " What if Planet 9 is a primordial black hole?." Physical Review Letters 125.5 (2020): 051103.

Brown, Michael E., and Konstantin Batygin. " Observational constraints on the orbit and location of planet nine in the outer solar system." The Astrophysical Journal Letters 824.2 (2016): L23.

Raymond, Sean N., et al. " Building the terrestrial planets: Constrained accretion in the inner Solar System." Icarus 203.2 (2009): 644-662.

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Solar System Planets: Order of the 8 (or 9) Planets

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Explore the eight (or nine) planets of the solar system in order from nearest to the sun and discover the many wonders of our solar system along the way.

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DNA, or deoxyribonucleic acid, is the hereditary material in humans and almost all other organisms. Nearly every cell in a person's body has the same DNA. Most DNA is located in the cell nucleus (where it is called nuclear DNA), but a small amount of DNA can also be found in the mitochondria (where it is called mitochondrial DNA or mtDNA). Mitochondria are structures within cells that convert the energy from food into a form that cells can use.

The information in DNA is stored as a code made up of four chemical bases: adenine (A), guanine (G), cytosine (C), and thymine (T). Human DNA consists of about 3 billion bases, and more than 99 percent of those bases are the same in all people. The order, or sequence, of these bases determines the information available for building and maintaining an organism, similar to the way in which letters of the alphabet appear in a certain order to form words and sentences.

DNA bases pair up with each other, A with T and C with G, to form units called base pairs. Each base is also attached to a sugar molecule and a phosphate molecule. Together, a base, sugar, and phosphate are called a nucleotide. Nucleotides are arranged in two long strands that form a spiral called a double helix. The structure of the double helix is somewhat like a ladder, with the base pairs forming the ladder's rungs and the sugar and phosphate molecules forming the vertical sidepieces of the ladder.

An important property of DNA is that it can replicate, or make copies of itself. Each strand of DNA in the double helix can serve as a pattern for duplicating the sequence of bases. This is critical when cells divide because each new cell needs to have an exact copy of the DNA present in the old cell.

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DNA, or deoxyribonucleic acid, is the hereditary material in humans and almost all other organisms. Nearly every cell in a person's body has the same DNA. Most DNA is located in the cell nucleus (where it is called nuclear DNA), but a small amount of DNA can also be found in the mitochondria (where it is called mitochondrial DNA or mtDNA).

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Engineers at The Australian National University (ANU) have invented a semiconductor with organic and inorganic materials that can convert electricity into light very efficiently, and it is thin and flexible enough to help make devices such as mobile phones bendable.

The invention also opens the door to a new generation of high-performance electronic devices made with organic materials that will be biodegradable or that can be easily recycled, promising to help substantially reduce e-waste.

The huge volumes of e-waste generated by discarded electronic devices around the world is causing irreversible damage to the environment. Australia produces 200,000 tonnes of e-waste every year -- only four per cent of this waste is recycled.

The organic component has the thickness of just one atom -- made from just carbon and hydrogen -- and forms part of the semiconductor that the ANU team developed. The inorganic component has the thickness of around two atoms. The hybrid structure can convert electricity into light efficiently for displays on mobile phones, televisions and other electronic devices.

Lead senior researcher Associate Professor Larry Lu said the invention was a major breakthrough in the field.

"For the first time, we have developed an ultra-thin electronics component with excellent semiconducting properties that is an organic-inorganic hybrid structure and thin and flexible enough for future technologies, such as bendable mobile phones and display screens," said Associate Professor Lu from the ANU Research School of Engineering.

PhD researcher Ankur Sharma, who recently won the ANU 3-Minute Thesis competition, said experiments demonstrated the performance of their semiconductor would be much more efficient than conventional semiconductors made with inorganic materials such as silicon.

"We have the potential with this semiconductor to make mobile phones as powerful as today's supercomputers," said Mr Sharma from the ANU Research School of Engineering.

"The light emission from our semiconducting structure is very sharp, so it can be used for high-resolution displays and, since the materials are ultra-thin, they have the flexibility to be made into bendable screens and mobile phones in the near future."

The team grew the organic semiconductor component molecule by molecule, in a similar way to 3D printing. The process is called chemical vapour deposition.

"We characterised the opto-electronic and electrical properties of our invention to confirm the tremendous potential of it to be used as a future semiconductor component," Associate Professor Lu said.

"We are working on growing our semiconductor component on a large scale, so it can be commercialised in collaboration with prospective industry partners."

Journal Reference:

Linglong Zhang, Ankur Sharma, Yi Zhu, Yuhan Zhang, Bowen Wang, Miheng Dong, Hieu T. Nguyen, Zhu Wang, Bo Wen, Yujie Cao, Boqing Liu, Xueqian Sun, Jiong Yang, Ziyuan Li, Arara Kar, Yi Shi, Daniel Macdonald, Zongfu Yu, Xinran Wang, Yuerui Lu. Efficient and Layer-Dependent Exciton Pumping across Atomically Thin Organic-Inorganic Type-I Heterostructures. Advanced Materials, 2018; 30 (40): 1803986 DOI: 10.1002/adma.201803986

Cite This Page:

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technology; graphene; electronics; materials science; chemistry; spintronics; engineering and construction; organic chemistry

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Part-organic invention can be used in bendable mobile phones

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Engineers at The Australian National University (ANU) have invented a semiconductor with organic and inorganic materials that can convert electricity into light very efficiently, and it is thin and flexible enough to help make devices such as mobile phones bendable.

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jeremy roos

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Flesh-eating screwworms have infested a larger portion of the Florida Keys than previously thought, according to a joint announcement Tuesday by the U.S. Department of Agriculture and Florida Department of Agriculture.

Two weeks ago, this blow fly and its parasitic maggots were thought to be contained on two islands - Big Pine Key and No Name Key - causing the state to issue an agricultural state of emergency. Adult screwworms are now infesting islands of Middle Torch Key, Little Torch Key, Cudjoe, Ramrod and Summerland. Officials said close to 100 deer in the Florida Keys have died. A dog, feral cat and pig have also tested positive.

Screwworms will live inside an animal until it is deceased.

Nearby states have started taking precautions. Robert Cobb, Georgia's State Veterinarian, has banned the import of animals from the quarantined area in the Florida Keys unless a special permit is issued.

"Please make yourself familiar with Screwworms and how they present in animals. Be alert." Cobb said in a statement. "This can rapidly cause serious illness and even death."

So, here's what you need to know about these buggers, just in case this festering outbreak continues to grow.
1. Last time the U.S. had a screwworm outbreak, 'Eye of the Tiger' topped the Billboard charts
The last reported case of screwworms in the U.S. was reported on August 30, 1982 in Starr County, Texas. Florida's ongoing outbreak is the state's first in half a century.

"It's an age thing," Texas A&M livestock and veterinary entomologist Sonja told PBS NewsHour. "Anybody under the age of 40 knows nothing about this screwworm unless you went to school to learn about bugs."
2. Two screwworms roam this Earth, one worse than the other
There are two types of screwworm flies: Old World (Chrysomya bezziana) and New World (Cochliomyia hominivorax). "Hominivorax," by the way, means "man-eater."

Old World screwworms are present throughout Africa, Southeast Asia and several countries on the west coast of the Persian Gulf. Meanwhile, the New World species sticks to the western hemisphere. They have similar parasitic needs and nearly identical lifecycles.

However, New World screwworms, such as those in Florida, outmatch their Old World cousins by laying more than one clutch of eggs at a time. In fact, New World flies can lay six to eight batches or more into a wound. Deaths appear to be more common with New World than Old World screwworms.

New and Old World screwworms are the only flies that consume live flesh as a primary food source, Swiger said, and the closest alternative in this regard is botflies.

But botflies create a wound with a small number of eggs to avoid killing their host. Once botfly maggots mature into adults, they take off. Screwworms, in contrast, will live inside an animal until it is deceased.
3. Flesh-munching screwworms attack humans, but we're Plan B on the menu
Humans can catch screwworms in the same manner as other warm-blooded animals. Mother screwworm flies are attracted by the smell of open wounds. Upon finding one, the fly lays its eggs, which hatch and go to work.

The maggots' powerful jaws slice through tissue, allowing the larvae to dig close to two inches into a wound. Little spines on the outside of the screwworm anchor into the tissue, making the creepy crawlers hard to remove.

The buggers can also squirm into the belly buttons of newborn mammals.

Aside from open wounds, screwworms can invade mucus-covered tissue - like that in eyes, ears, nostrils and the anus. The buggers can also squirm into the belly buttons of newborn mammals.

The screwworms then expand their feeding area from skin into deeper tissue, such as muscles. The larvae eventually crawl out of an animal and fall to the ground, where they mature into adult flies An infestation of screwworm maggots on a human body is called myiasis.

So far in Florida, livestock and house pets have tested positive for screwworms, but no humans.

In fact, human infestations, in general, are rare. "It is actually very rare for screwworms to infest humans. We're their last choice usually," Swiger said. If left untreated, myiasis can be fatal, but that's also an uncommon outcome for humans.
4. Screwworms are tricky to treat, so cover those wounds, especially with pets
Here's what you should do in the unlikely event that you, a friend or a pet catch screwworms.

No medications are available, at least none approved by the FDA. Therapy options are limited to surgical removal of the pests and antibiotics to prevent secondary infections by other germs.

" With pets, you could go to a vet and help remove maggots but we do not have that option with wild animals," Dr. Swiger said.

Ranchers can tend to tackle livestock infestations by rubbing approved insecticides into the wound, which is followed by pulling out individual larva with tweezers.

Any open wound is attractive to the New World screwworm, either natural or human-inflicted. Female screwworm eggs reach maturity within five days after hatching. This can result in up to 3,000 larvae being present in a single wound.

"They get into a wound, and even if you have a chemical control, it won't heal the wound," Swiger said. For now, she says the most effective prevention method is to watch your animals.
5. Human cases are cringeworthy
Yes, what follows is gross.

A 4-year-old girl in India was once treated for a screwworm infestation inside her rectum. Her rectal ulcer had grown to 1.9 inches by 1.2 inches. That's roughly twice the size of a quarter.

"[The] wound became maggot free in four days during which hundreds of whitish briskly motile maggots measuring 10-18 mm [0.39 - 0.71 inches long] were retrieved," according to a case report from Department of Pediatrics at RD Gardi Medical College.

Another case of a 12-year-old girl was reported in 2008, after she returned to the U.S. from a trip in Colombia. Doctors in Connecticut had to manually extract 142 larvae from the girl's scalp.
6. Salvation is coming by way of Panama
In 1972, the U.S. and Mexico established the Screwworm Eradication Program agreement. By 1991, Animal and Plant Health Inspection Service had a 6-year action plan to eradicate the screwworm from all of Central and North America.

The plan involved using planes to airdrop sterile male flies across hard hit regions.

To achieve maximum eradication, the Mexico-United States Commission developed flight paths to release millions of sterile flies in Mexico, Panama, El Salvador, Costa Rica and other areas at risk including Texas, Arizona and California.

The mutant males competed with normal ones for females, and ultimately wiped out the New World screwworm population from the U.S. and Mexico by 1984.

But eradication labs tend to move south, once an affected area has been eradicated. Today, USDA and its partners maintain a permanent sterile fly barrier between Panama and Colombia to prevent the establishment of any deadly flies from South America. The screwworm rearing facility is located in Pacora, Colombia, and is capable of producing 200 million flies per week.

"We still have screwworms being produced in the eradication program, in Panama, which is shipping worms to Florida," Swiger said. This transport process started on October 11 for the Florida Keys.

7. If the screwworm outbreak spreads, it'll cost us

Now that screwworms are back, Swiger expects eradication efforts to take months.

"I don't know if they'll ever figure it out how it got there. In the past, we know people traveled with animals. But this is a wild native species and finding several deer infested is troubling especially when it has not been reported how," Swiger said.

Flies on their own can travel several miles without any wind behind them. Good news is Hurricane Matthew did not directly hit the Keys, which makes additional infestations less likely.

The main worry at the moment revolves around a lack of surveillance, Swiger said. Most fly species fall for traps, but such devices don't exist for screwworms.

That's too bad because the stakes are high for livestock owners. The cattle market was so affected by the last outbreak that the nation was essentially forced into an eradication program, Swiger said.

By 1930, screwworms had spread to the southeast, where livestock producers in the U.S. were losing $400 million annually. In 1957, Florida state legislature allotted $3 million for an eradication program.

These days, USDA estimates the nation's livestock industry could lose $750 million a year from a widespread screwworm outbreak.

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7 reasons flesh-eating screwworms are as gross as you think

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Flesh-eating screwworms have infested a larger portion of the Florida Keys than previously thought, according to a joint announcement Tuesday by the U.S. Department of Agriculture and Florida Department of Agriculture. Two weeks ago, this blow fly and its parasitic maggots were thought to be contained on two islands - Big Pine Key and No Name Key - causing the state to issue an agricultural state of emergency.

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The oldest flying squirrel fossil ever found has unearthed new insight on the origin and evolution of these airborne animals.

Writing in the open-access journal eLife, researchers from the Institut Català de Paleontologia Miquel Crusafont (ICP) in Barcelona, Spain, described the 11.6-million-year-old fossil, which was discovered in Can Mata landfill, approximately 40 kilometers outside the city.

"Due to the large size of the tail and thigh bones, we initially thought the remains belonged to a primate," says first author Isaac Casanovas-Vilar, researcher at the ICP. In fact, and much to the disappointment of paleoprimatologists, further excavation revealed that it was a large rodent skeleton with minuscule specialised wrist bones, identifying it as Miopetaurista neogrivensis -- an extinct flying squirrel.

Combining molecular and paleontological data to carry out evolutionary analyses of the fossil, Casanovas-Vilar and the team demonstrated that flying squirrels evolved from tree squirrels as far back as 31 to 25 million years ago, and possibly even earlier.

In addition, their results showed that Miopetaurista is closely related to an existing group of giant flying squirrels called Petaurista. Their skeletons are in fact so similar that the large species that currently inhabits the tropical and subtropical forests of Asia could be considered living fossils.

With 52 species scattered across the northern hemisphere, flying squirrels are the most successful group of mammals that adopted the ability to glide. To drift between trees in distances of up to 150 metres, these small animals pack their own 'parachute': a membrane draping between their lower limbs and the long cartilage rods that extend from their wrists. Their tiny, specialised wrist bones, which are unique to flying squirrels, help support the cartilaginous extensions.

But the origin of these animals is highly debated. While most genetic studies point towards the group splitting from tree squirrels about 23 million years ago, some 36-million-year-old remains that could belong to flying squirrels have previously been found. "The problem is that these ancient remains are mainly teeth," Casanovas-Vilar explains. "As the dental features used to distinguish between gliding and non-gliding squirrels may actually be shared by the two groups, it is difficult to attribute the ancient teeth undoubtedly to a flying squirrel. In our study, we estimate that the split took place around 31 and 25 million years ago, earlier than previously thought, suggesting the oldest fossils may not belong to flying squirrels.

"Molecular and paleontological data are often at odds, but this fossil shows that they can be reconciled and combined to retrace history," he adds. "Discovering even older fossils could help to retrace how flying squirrels diverged from the rest of their evolutionary tree."
An exceptional site in a rubbish dump
The Can Mata landfill holds a set of more than 200 sites ranging in age between 12.6 and 11.4 Ma (middle to late Miocene). In the last 20 years, excavations carried out by the ICP in Can Mata have led to the identification of more than 80 species of mammals, birds, amphibians and reptiles. A remarkable number of primate remains from the site have revealed three new species of hominoids, nicknamed 'Pau' (Pierolapithecus catalaunicus), 'Laia' (Pliobates cataloniae) and 'Lluc' (Anoiapithecus brevirostris). Various studies of mammal remains recovered from the site, including the current work in eLife, indicate the existence of a dense subtropical forest.

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new species; trees; evolutionary biology; nature; fossils; evolution; early mammals; origin of life

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Oldest fossil of a flying squirrel sheds new light on its evolutionary tree

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The oldest flying squirrel fossil ever found has unearthed new insight on the origin and evolution of these airborne animals. Writing in the open-access journal eLife, researchers from the Institut Català de Paleontologia Miquel Crusafont (ICP) in Barcelona, Spain, described the 11.6-million-year-old fossil, which was discovered in Can Mata landfill, approximately 40 kilometers outside the city.

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https://www.forbes.com/sites/startswithabang/2018/01/23/the-three-meanings-of-emc2-einsteins-most-famous-equation/#2180f70871c0

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A novel tiny, soft robot with caterpillar-like legs capable of carrying heavy loads and adaptable to adverse environment was developed from a research led by City University of Hong Kong (CityU). This mini delivery-robot could pave way for medical technology advancement such as drugs delivery in human body.

Around the world, there has been research about developing soft milli-robots. But the CityU's new design with multi-legs helps reduce friction significantly, so that the robot can move efficiently inside surfaces within the body lined with, or entirely immersed in, body fluids such as blood or mucus.

The research findings have been published in the latest issue of the scientific journal Nature Communications, titled "A Bio-inspired Multilegged Soft Millirobot that Functions in Both Dry and Wet Conditions."
Bio-inspired robot design
What makes this milli-robot stand out is its hundreds of less than 1 mm long pointed legs that looks like short tiny hair. This unique design was not a random choice. The research team has studied the leg structures of hundreds of ground animals including those with 2, 4, 8 or more legs, in particular the ratio between leg-length and the gap between the legs. And from there, they got their inspiration.

"Most animals have a leg-length to leg-gap ratio of 2:1 to 1:1. So we decided to create our robot using 1:1 proportion," explains Dr Shen Yajing, Assistant Professor at CityU's Department of Biomedical Engineering (BME), who led the research.

The robot's body thickness measures approximately 0.15 mm, with each conical leg measuring 0.65 mm long and the gap between the legs measuring approximately 0.6 mm, making the leg-length-to-gap ratio around 1:1. Moreover, the robot's pointed legs have greatly reduced their contact area and hence the friction with the surface. Laboratory tests showed that the multi-legged robot has 40 times less friction than a limbless robot in both wet and dry environment.

Apart from the multi-leg design, the materials also matter. The robot is fabricated with a silicon material called polydimethylsiloxane (PDMS) embedded with magnetic particles which enables it to be remotely controlled by applying electromagnetic force. "Both the materials and the mutli-leg design greatly improve the robot's hydrophobic property. Besides, the rubbery piece is soft and can be cut easily to form robots of various shapes and sizes for different applications," says Professor Wang Zuankai at CityU's Department of Mechanical Engineering (MNE) who conceived this research idea and initiated the collaboration among the researchers.
Moving at ease in harsh environment
Controlled by a magnetic manipulator used in experiments, the robot can move in both a flap propulsion pattern and an inverted pendulum pattern, meaning that it can use its front feet to flap forward as well as swinging the body by standing on the left and right feet alternately to advance respectively.

"The rugged surface and changing texture of different tissues inside the human body make transportation challenging. Our multi-legged robot shows an impressive performance in various terrains and hence open wide applications for drug delivery inside the body," says Professor Wang.

The research team further proved that when facing an obstacle ten times higher than its leg length, the robot, with its deformable soft legs, is capable to lift up one end of its body to form an angle of up to 90-degree and cross the obstacle easily. And the robot can increase its speed by increasing the electromagnetic frequency applied.

The robot also shows a remarkable loading ability. Laboratory tests showed that the robot was capable of carrying a load 100 times heavier than itself, a strength comparable to an ant, one of the strongest Hercules in nature, or to a human being able to easily lift a 26-seated mini-bus.

The amazingly strong carrying capability, efficient locomotion and good obstacle-crossing ability make this milli-robot extremely suitable for applications in a harsh environment, for example delivering a drug to a designated spot through the digestive system, or carrying out medical inspection," adds Dr Shen.

Before conducting further tests in animals and eventually in humans, the research teams are further developing and refining their research in three aspects, namely finding a biodegradable material, studying new shapes, and adding extra features.

"We are hoping to create a biodegradable robot in the next two to three years so it will decompose naturally after its meds delivery mission," says Dr Shen.

The co-first authors of the paper are Lu Haojian from BME Department and Dr Zhang Mei from MNE Department of CityU. The other co-authors include Yang Yuanyuan from BME Department of CityU, and Professor Huang Qiang and Professor Toshio Fukuda from the Beijing Institute of Technology.

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medical devices; pharmacology; restless leg syndrome; robotics research; engineering; vehicles; robotics; artificial intelligence; software

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Tiny soft robot with multilegs paves way for drugs delivery in human body

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A novel tiny, soft robot with caterpillar-like legs capable of carrying heavy loads and adaptable to adverse environment was developed from a research led by City University of Hong Kong (CityU). This mini delivery-robot could pave way for medical technology advancement such as drugs delivery in human body.

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Credit: Vadim Sadovski/Shutterstock

The Earth's mantle acts like a giant churn, circulating cool oceanic crust downward toward the core, where it heats up into a goopy solid and then rises again - a process that powers everything from plate tectonics to volcanism.

But there are some hitches in this system, and new research reveals why: A slippery layer about 416 miles (670 kilometers) deep stops chunks of crust in their tracks, creating "stagnant slabs" in the middle of the mantle, the layer between the Earth's crust and its core. [ In Photos: Ocean Hidden Beneath Earth's Surface]

"This deflection of slabs was always puzzling to our understanding of [the mantle]," said Shijie Zhong, a physicist at the University of Colorado Boulder and the co-author of the new study published Oct. 1 in the journal Nature Geoscience.

There is no way to look directly at the mantle, but scientists study its dynamics using seismic waves from earthquakes. By detecting the waves as they propagate through the globe, researchers can construct a picture of the mantle, not unlike how radar can image objects using radio waves.

What happens in the mantle is related to what's going on in the crust. The crust is made up of tectonic plates that ride across the mantle like rafts on a very, very thick sea (the consistency of the crust is similar to that of hot asphalt). In some areas, called subduction zones, one tectonic plate dives under another, grinding chunks of oceanic crust down into the mantle. From seismology, Zhong said, researchers knew that some of these slabs of crust don't always travel the full 1,860 miles (3,000 km) to the core-mantle boundary. Essentially, they get stuck partway down.

Particularly in the western Pacific Ocean, near Japan and at the Mariana Trench, for example, the slabs of crust seem to stall out at around 416 miles (670 km) deep. In these areas, they seem to deflect and travel horizontally as much as 1,243 miles (2,000 km).

The layer of mantle at that particular depth is unusual, Zhong said, because the rock there goes through a sudden density increase, which is the result of the pressure of all the rock pushing down on top of it. In the new study, Zhong and University of Colorado graduate student Wei Mao built a computer model of the mantle's dynamics, including both this density increase and the past 130 million years of continental plate movements.

This more complete model of the mantle naturally produced the same sort of stagnating slabs seen in the real mantle, the researchers found. What seems to be going on, Zhong said, is that the accumulated pressure of the overlying rock at 670 km creates an area of reduced viscosity - in essence, the mantle is more slippery and less gooey.

"That reduced viscosity essentially provides what we call lubrication on the slabs," Zhong said. The chunks of crust are able to slip and slide sideways instead of continuing their downward plunge.

This hitch in the machine is only temporary. The slabs are probably only trapped for 20 million years or so, Zhong said - a blink of the eye in terms of Earth's history. But their dynamics might be important for some of the geological phenomena seen on the surface. For example, volcanic activity in northeastern China, far from the volcanic arc of Japan, could be due, in part, to some of these slab dynamics, Zhong said.

The model doesn't answer all the questions about the stagnating slabs. It's not clear, Zhong said, why the western Pacific seems to give rise to so many of these stagnant slabs, while subduction zones near North and South America currently don't. There are also other mystery spots around the globe, he said.

"In places like New Zealand, there is still some disagreement between our convection model and the observations," he said, "so we need to reconcile those places."

Original article on Live Science.

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Scientists Find Weird Reason Diving Plates Get Stuck 400 Miles Beneath Earth's Surface

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The Earth's mantle acts like a giant churn, circulating cool oceanic crust downward toward the core, where it heats up into a goopy solid and then rises again - a process that powers everything from plate tectonics to volcanism.

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Credit: Shutterstock

Physicists have revealed that just seven quantum particles can behave as if they were in a crowd of billions.

At larger scales, matter goes through changes, called phase transitions, in which (for example) water turns into a solid (ice) or a vapor (steam). Scientists were used to seeing this behavior in large masses of molecules, but never in such a tiny cluster.

In a new study, detailed today (Sept. 10) in the journal Nature Physics, researchers witnessed these phase transitions in systems made up of just seven light particles, or photons, which took on an exotic physical state known as a Bose-Einstein condensate (BEC). That's the physical state that matter can reach at ultracold temperatures, in which particles begin to blend together and act in unison.

Because photons are packets of light, they're made of energy, not matter, which makes the idea of them going through a phase transition strange. But back in 2010, a team of German researchers showed that light particles could be induced to behave as a BEC would, just like their matter-particle cousins.

To trap the photons, those researchers built a small mirrored chamber and filled it with a colored dye. When the light particles banged into the dye particles, the dye particles would absorb them and re-emit them, so the photons took longer to move through the chamber - effectively slowing them down. When the photons struck the chamber's mirrored walls, the photons would bounce off without being absorbed or escaping. So the chamber was effectively a space where researchers could make photons sluggish and put them in close quarters. And in that situation, the physicists found, the photons would interact with one another like matter, and exhibit behaviors recognizable as those of a BEC.

In the more recent experiment, the researchers wanted to figure out the minimum number of photons necessary for that to happen. Using a fine-tuned laser, they pumped photons into a similar dye-filled mirror trap one at a time and observed the concoction to figure out when a BEC would emerge. They found that after an average of just seven photons, the photons formed a BEC - they began acting like one particle. That's a new low bar for particle counts necessary for a phase transition. [ The Coolest Little Particles in Nature]

"Now that it's confirmed that 'phase transition' is still a useful concept in such small systems, we can explore properties in ways that would not be possible in larger systems," lead author Robert Nyman, a physicist at Imperial College London, said in a statement.

There were some differences between the micro-BEC and phase transitions involving larger groups of particles, the researchers noted. When ice heats up past its melting point, it seems to go from solid to liquid form instantly, without any in-between stage. The same is true for most phase transitions of most chemicals. But the seven-photon BEC seemed to form a bit more gradually, the researchers said in the statement, rather than all at once.

Still, they wrote in the paper, the photon phase transition showed that even at very small scales, phase transitions are remarkably like what's common at larger scales. Physics is physics, all the way down.

Originally published on Live Science.

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7 Quantum Particles Act Like Billions in Weird Physics Experiment

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Physicists have revealed that just seven quantum particles can behave as if they were in a crowd of billions. At larger scales, matter goes through changes, called phase transitions, in which (for example) water turns into a solid (ice) or a vapor (steam).

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Egoism, Machiavellianism, narcissism, psychopathy, sadism, spitefulness, and others are among the traits that stand for the malevolent dark sides of human personality. As results from a recently published German-Danish research project show, these traits share a common 'dark core'. So, if you have one of these tendencies, you are also likely to have one or more of the others.

Both world history and everyday life are full of examples of people acting ruthlessly, maliciously, or selfishly. In psychology as well as in everyday language, we have diverse names for the various dark tendencies human may have, most prominently psychopathy (lack of empathy), narcissism (excessive self-absorption), and Machiavellianism (the belief that the ends justify the means), the so-called 'dark triad', along with many others such as egoism, sadism, or spitefulness.

Although at first glance there appear to be noteworthy differences between these traits -- and it may seem more 'acceptable' to be an egoist than a psychopath -- new research shows that all dark aspects of human personality are very closely linked and are based on the same tendency. That is, most dark traits can be understood as flavoured manifestations of a single common underlying disposition: The dark core of personality. In practice, this implies that if you have a tendency to show one of these dark personality traits, you are also more likely to have a strong tendency to display one or more of the others.

As the new research reveals, the common denominator of all dark traits, the D-factor, can be defined as the general tendency to maximize one's individual utility -- disregarding, accepting, or malevolently provoking disutility for others -- , accompanied by beliefs that serve as justifications.

In other words, all dark traits can be traced back to the general tendency of placing one's own goals and interests over those of others even to the extent of taking pleasure in hurting other's -- along with a host of beliefs that serve as justifications and thus prevent feelings of guilt, shame, or the like. The research shows that dark traits in general can be understood as instances of this common core -- although they may differ in which aspects are predominant (e.g., the justifications-aspect is very strong in narcissism whereas the aspect of malevolently provoking disutility is the main feature of sadism) .

Ingo Zettler, Professor of Psychology at the University of Copenhagen, and two German colleagues, Morten Moshagen from Ulm University and Benjamin E. Hilbig from the University of Koblenz-Landau, have demonstrated how this common denominator is present in nine of the most commonly studied dark personality traits:

Egoism: an excessive preoccupation with one's own advantage at the expense of others and the community

Machiavellianism: a manipulative, callous attitude and a belief that the ends justify the means

Moral disengagement: cognitive processing style that allow behaving unethically without feeling distress

Narcissism: excessive self-absorption, a sense of superiority, and an extreme need for attention from others

Psychological entitlement: a recurring belief that one is better than others and deserves better treatment

Psychopathy: lack of empathy and self-control, combined with impulsive behaviour

Sadism: a desire to inflict mental or physical harm on others for one's own pleasure or to benefit oneself

Self-interest: a desire to further and highlight one's own social and financial status

Spitefulness: destructiveness and willingness to cause harm to others, even if one harms oneself in the process

In a series of studies with more than 2,500 people, the researchers asked to what extent people agreed or disagreed with statements such as "It is hard to get ahead without cutting corners here and there.," "It is sometimes worth a little suffering on my part to see others receive the punishment they deserve.," or "I know that I am special because everyone keeps telling me so." In addition, they studied other self-reported tendencies and behaviors such as aggression or impulsivity and objective measures of selfish and unethical behaviour.

The researchers' mapping of the common D-factor, which has just been published in the academic journal Psychological Review, can be compared to how Charles Spearman showed about 100 years ago that people who score highly in one type of intelligence test typically also score highly in other types of intelligence tests, because there is something like a general factor of intelligence.

"In the same way, the dark aspects of human personality also have a common denominator, which means that -- similar to intelligence -- one can say that they are all an expression of the same dispositional tendency," Ingo Zettler explains.

'For example, in a given person, the D-factor can mostly manifest itself as narcissism, psychopathy or one of the other dark traits, or a combination of these. But with our mapping of the common denominator of the various dark personality traits, one can simply ascertain that the person has a high D-factor. This is because the D-factor indicates how likely a person is to engage in behaviour associated with one or more of these dark traits', he says. In practice, this means that an individual who exhibits a particular malevolent behaviour (such as likes to humiliate others) will have a higher likelihood to engage in other malevolent activities, too (such as cheating, lying, or stealing).

The nine dark traits are by no means the same, and each can result in specific kinds of behaviour. However, at their core, the dark traits typically have far more in common that actually sets them apart. And knowledge about this 'dark core' can play a crucial role for researchers or therapists who work with people with specific dark personality traits, as it is this D-factor that affects different types of reckless and malicious human behaviour and actions, often reported in the media.

'We see it, for example, in cases of extreme violence, or rule-breaking, lying, and deception in the corporate or public sectors. Here, knowledge about a person's D-factor may be a useful tool, for example to assess the likelihood that the person will reoffend or engage in more harmful behaviour', he says.
Fact box:
Dark personality traits studied in the research project:

Egoism

Machiavellianism

Moral disengagement

Narcissism

Psychological entitlement

Psychopathy

Sadism

Self-interest

Spitefulness

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workplace health; cold and flu; healthy aging; borderline personality disorder; autism; psychology; stem education; poverty and learning; scientific conduct

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Psychologists define the 'dark core of personality'

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Egoism, Machiavellianism, narcissism, psychopathy, sadism, spitefulness are all traits that stand for the malevolent dark sides of human personality. Results from a recent project show, these traits share a common 'dark core.' So, if you have one of these tendencies, you are also likely to have one or more of the others.

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factmonster.com, image: https://pixabay.com (public domain)

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Scientists have created a mutant enzyme that breaks down plastic drinks bottles - by accident. The breakthrough could help solve the global plastic pollution crisis by enabling for the first time the full recycling of bottles.

The new research was spurred by the discovery in 2016 of the first bacterium that had naturally evolved to eat plastic, at a waste dump in Japan. Scientists have now revealed the detailed structure of the crucial enzyme produced by the bug.

The international team then tweaked the enzyme to see how it had evolved, but tests showed they had inadvertently made the molecule even better at breaking down the PET (polyethylene terephthalate) plastic used for soft drink bottles. "What actually turned out was we improved the enzyme, which was a bit of a shock," said Prof John McGeehan, at the University of Portsmouth, UK, who led the research. "It's great and a real finding."

The mutant enzyme takes a few days to start breaking down the plastic - far faster than the centuries it takes in the oceans. But the researchers are optimistic this can be speeded up even further and become a viable large-scale process.

"What we are hoping to do is use this enzyme to turn this plastic back into its original components, so we can literally recycle it back to plastic," said McGeehan. "It means we won't need to dig up any more oil and, fundamentally, it should reduce the amount of plastic in the environment."

About 1m plastic bottles are sold each minute around the globe and, with just 14% recycled, many end up in the oceans where they have polluted even the remotest parts, harming marine life and potentially people who eat seafood. "It is incredibly resistant to degradation. Some of those images are horrific," said McGeehan. "It is one of these wonder materials that has been made a little bit too well."

However, currently even those bottles that are recycled can only be turned into opaque fibres for clothing or carpets. The new enzyme indicates a way to recycle clear plastic bottles back into clear plastic bottles, which could slash the need to produce new plastic.

"You are always up against the fact that oil is cheap, so virgin PET is cheap," said McGeehan. "It is so easy for manufacturers to generate more of that stuff, rather than even try to recycle. But I believe there is a public driver here: perception is changing so much that companies are starting to look at how they can properly recycle these."

PET - or polyethylene terephthalate - is the most common plastic used for soft drinks bottles. This is because it is lightweight, shatterproof, easy to mould and colour and cheap to produce. The key raw material is oil. PET in a different form is also used in clothing, where it is called polyester.

The estimated recycling rates for PET bottles vary significantly around the world, from 31% in the US, to 48% in Europe, 72% in Japan and 90% in India, where rag pickers collect the bottles to sell to waste traders. Deposit return schemes are very successful in some countries. But, globally, many bottles end polluting the environment.

PET bottles that are recycled have to be cleaned, sorted by colour, then shredded and dried to produce PET flakes. These can then be used to make new plastic but, due to impurities, it is not usually possible to make new, clear PET bottles. Instead, recycled bottles are mostly used to make polyester fibres.

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The new research, published in the journal Proceedings of the National Academy of Sciences, began by determining the precise structure of the enzyme produced by the Japanese bug. The team used the Diamond Light Source, near Oxford, UK, an intense beam of X-rays that is 10bn times brighter than the sun and can reveal individual atoms.

The structure of the enzyme looked very similar to one evolved by many bacteria to break down cutin, a natural polymer used as a protective coating by plants. But when the team manipulated the enzyme to explore this connection, they accidentally improved its ability to eat PET.

"It is a modest improvement - 20% better - but that is not the point," said McGeehan. "It's incredible because it tells us that the enzyme is not yet optimised. It gives us scope to use all the technology used in other enzyme development for years and years and make a super-fast enzyme."

Industrial enzymes are widely used in, for example, washing powders and biofuel production, They have been made to work up to 1,000 times faster in a few years, the same timescale McGeehan envisages for the plastic-eating enzyme. A patent has been filed on the specific mutant enzyme by the Portsmouth researchers and those from the US National Renewable Energy Laboratory in Colorado.

One possible improvement being explored is to transplant the mutant enzyme into an "extremophile bacteria" that can survive temperatures above 70C, at which point PET changes from a glassy to a viscous state, making it likely to degrade 10-100 times faster.

Earlier work had shown that some fungi can break down PET plastic, which makes up about 20% of global plastic production. But bacteria are far easier to harness for industrial uses.

Other types of plastic could be broken down by bacteria currently evolving in the environment, McGeehan said: "People are now searching vigorously for those." PET sinks in seawater but some scientists have conjectured that plastic-eating bugs might one day be sprayed on the huge plastic garbage patches in the oceans to clean them up.

"I think [the new research] is very exciting work, showing there is strong potential to use enzyme technology to help with society's growing waste problem," said Oliver Jones, a chemist at RMIT University in Melbourne, Australia, and not part of the research team.

"Enzymes are non-toxic, biodegradable and can be produced in large amounts by microorganisms," he said. "There is still a way to go before you could recycle large amounts of plastic with enzymes, and reducing the amount of plastic produced in the first place might, perhaps, be preferable. [But] this is certainly a step in a positive direction."

Prof Adisa Azapagic, at the University of Manchester in the UK, agreed the enzyme could be useful but added: "A full life-cycle assessment would be needed to ensure the technology does not solve one environmental problem - waste - at the expense of others, including additional greenhouse gas emissions."

This article was amended on 17 April 2018 to make clear that PET becomes viscous above 70C. Its melting point is above 250C.

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Scientists accidentally create mutant enzyme that eats plastic bottles

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Scientists have created a mutant enzyme that breaks down plastic drinks bottles - by accident. The breakthrough could help solve the global plastic pollution crisis by enabling for the first time the full recycling of bottles. The new research was spurred by the discovery in 2016 of the first bacterium that had naturally evolved to eat plastic, at a waste dump in Japan.

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Astronomers from Lund University in Sweden have now found the explanation to a recent mystery at the centre of the Milky Way galaxy: the high levels of scandium discovered last spring near the galaxy's giant black hole were in fact an optical illusion.

Last spring, researchers published a study about the apparent presence of astonishing and dramatically high levels of three different elements in red giant stars, located less than three light years away from the big black hole at the centre of our galaxy. Various possible explanations were presented, for example that the high levels were a result of earlier stars being disrupted as they fall into the black hole, or a result of debris from the collisions of neutron stars.

Now another group of astronomers from Lund University among others, in collaboration with UCLA in California, have found an explanation for the high levels of scandium, vanadium and yttrium. They argue that the so-called spectral lines presented last spring were actually an optical illusion. Spectral lines are used to find out which elements a star contains -- by using its own light.

"These giant red stars have used up most of their hydrogen fuel and their temperatures are therefore only half of the sun's," says Brian Thorsbro, lead author of the study and doctoral student in astronomy at Lund University.

According to the new study, the lower temperatures of the giant stars helped to create the optical illusion that appeared in the measurements of spectral lines. Specifically, it means that the electrons in the elements behave differently at different temperatures, which in turn can be misleading when measuring the spectral lines of elements in different stars. The conclusion is the result of a close collaboration between astronomers and atomic physicists.

Brian Thorsbro and his colleagues have had the world's largest telescope, at the W. M. Keck Observatory on Mauna Kea, Hawaii, at their disposal, thanks to their collaboration with R. Michael Rich at UCLA. Using this telescope and others, the research team is currently conducting a comprehensive mapping of the central areas of the Milky Way, exploring the spectral lines in the light from different stars to find out which elements they contain. The purpose is to gain an understanding of the events that have occurred in the history of the Milky Way, but also to understand how galaxies in general have formed.

"Our research collaboration is world-leading in terms of systematically mapping the elements contained in the huge central star cluster -- the star cluster that surrounds the black hole," says research leader and astronomer Nils Ryde at Lund University.

The spectral lines for different elements are recorded in a high-resolution spectrometer -- an advanced camera that generates a rainbow of the starlight. The research team has studied the part of the spectrum consisting of near-infrared light, i.e. the heat radiation emitted by the stars. The reason for this is that infrared light can penetrate the dust that obstructs the line-of-sight between us and the centre of the Milky Way, approximately 25,000 light years away. The technology for recording this light is very advanced, and has only recently become available to astronomers.

"We have only started to map the stellar compositions in these central areas of the Milky Way," says Nils Ryde.

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stars; galaxies; astronomy; black holes; astrophysics; cosmology; space telescopes; extrasolar planets

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Mystery at the center of the Milky Way solved

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Astronomers from Lund University in Sweden have now found the explanation to a recent mystery at the centre of the Milky Way galaxy: the high levels of scandium discovered last spring near the galaxy's giant black hole were in fact an optical illusion.

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Palaeopascichnus linearis, which resembles a chain of fossilized poop, is the earliest macroscopic creature found with an exoskeleton. Figures B and C show magnified images of the exoskeletons of sediment the creatures cemented to themselves with their own excretions.

Credit: nton Kolesnikov

Mysterious fossils found all over the world belong to creatures that built their own skeletons more than 550 million years ago.

Palaeopascichnus linearis is among the world's oldest skeletal creatures, according to new research published in the October issue of the journal Precambrian Research. These tiny globular, ocean bottom-dwellers may have been amoeba-like creatures that accrued bits of sand and sediment around themselves to create their own exoskeleton. All earlier organisms with similar exoskeletons were much, much smaller, said study leader Anton Kolesnikov, a paleontologist at the Institute of Petroleum Geology and Geophysics at the Siberian Branch of the Russian Academy of Sciences and the University of Lille in France. [ In Images: The Oldest Fossils on Earth]

"It is the oldest known macroscopic skeletal organism," Kolesnikov said of P. linearis.

Palaeopascichnus fossils are found the world over in rocks from the Ediacaran period, which spanned from 635 million to 541 million years ago. No one had been able to agree on exactly what the fossils were, though, Kolesnikov wrote in an email to Live Science. Some thought they were trace fossils left behind by some organism shuffling along the seafloor. Others suspected they were coprolites - fossilized poop. Still others argued they were organisms in and of themselves.

Figuring out the answer was difficult because many areas where Ediacaran fossils are found around the world are protected, Kolesnikov said. But in the Olenek Uplift of northeastern Siberia, past the Arctic Circle, Kolesnikov and his colleagues discovered sites where they collected more than 300 new specimens of the fossils. They also discovered more fossils from the area in collections dating back to the 1980s.

"Huge amounts of fossils from Siberia allowed us to experiment with thin sampling, sectioning, cutting, studying in [electron] microscopes" and more, Kolesnikov said.

This analysis revealed that the fossils were made up of chains of between two and 40 spherical or oval modules, each between 0.04 inches and 0.2 inches (1 and 5 millimeters) in diameter. Each module was bordered by a fine rim of sediment.

More than anything, the researchers reported, the fossils looked like today's xenophyophores, which are giant foraminifera. These bizarre creatures are amoebas that protect themselves with "agglutinated tests," or exoskeletons of sediment they cement to themselves with their own excretions. Scientists reporting in a March 2018 paper in the Zoological Journal detailed the discovery of a new species of these xenophyophores, Aschemonella monile, which look remarkably similar to the fossil versions from Siberia.

The oldest microorganisms with agglutinized skeletons date back to about 742 million years ago, the researchers wrote in their new study. But P. linearis, which dates back to around 613 million to 544 million years ago, may be the oldest non-microscopic organism to boast a skeleton. Previously, Kolesnikov said, macroscopic organisms (those visible to the naked eye) weren't thought to evolve skeletons until the Paleozoic. The new findings suggest this happened slightly before that, in the late Proterozoic.

Original article on Live Science.

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Petrified Chains of 'Poop' Turn Out to Be One of Earth's Oldest Skeletons

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Mysterious fossils found all over the world belong to creatures that built their own skeletons more than 550 million years ago. Palaeopascichnus linearis is among the world's oldest skeletal creatures, according to new research published in the October issue of the journal Precambrian Research.

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Is that circle green or gray? Are the center lines straight or tilted?

Optical illusions can be fun to experience and debate, but understanding how human brains perceive these different phenomena remains an active area of scientific research. For one class of optical illusions, called contextual phenomena, those perceptions are known to depend on context. For example, the color you think a central circle is depends on the color of the surrounding ring. Sometimes the outer color makes the inner color appear more similar, such as a neighboring green ring making a blue ring appear turquoise -- but sometimes the outer color makes the inner color appear less similar, such as a pink ring making a grey circle appear greenish.

A team of Brown University computer vision experts went back to square one to understand the neural mechanisms of these contextual phenomena. Their study was published on Sept. 20 in Psychological Review.

"There's growing consensus that optical illusions are not a bug but a feature," said Thomas Serre, an associate professor of cognitive, linguistic and psychological sciences at Brown and the paper's senior author. "I think they're a feature. They may represent edge cases for our visual system, but our vision is so powerful in day-to-day life and in recognizing objects."

For the study, the team lead by Serre, who is affiliated with Brown's Carney Institute for Brain Science, started with a computational model constrained by anatomical and neurophysiological data of the visual cortex. The model aimed to capture how neighboring cortical neurons send messages to each other and adjust one another's responses when presented with complex stimuli such as contextual optical illusions.

One innovation the team included in their model was a specific pattern of hypothesized feedback connections between neurons, said Serre. These feedback connections are able to increase or decrease -- excite or inhibit -- the response of a central neuron, depending on the visual context.

These feedback connections are not present in most deep learning algorithms. Deep learning is a powerful kind of artificial intelligence that is able to learn complex patterns in data, such as recognizing images and parsing normal speech, and depends on multiple layers of artificial neural networks working together. However, most deep learning algorithms only include feedforward connections between layers, not Serre's innovative feedback connections between neurons within a layer.

Once the model was constructed, the team presented it a variety of context-dependent illusions. The researchers "tuned" the strength of the feedback excitatory or inhibitory connections so that model neurons responded in a way consistent with neurophysiology data from the primate visual cortex.

Then they tested the model on a variety of contextual illusions and again found the model perceived the illusions like humans.

In order to test if they made the model needlessly complex, they lesioned the model -- selectively removing some of the connections. When the model was missing some of the connections, the data didn't match the human perception data as accurately.

"Our model is the simplest model that is both necessary and sufficient to explain the behavior of the visual cortex in regard to contextual illusions," Serre said. "This was really textbook computational neuroscience work -- we started with a model to explain neurophysiology data and ended with predictions for human psychophysics data."

In addition to providing a unifying explanation for how humans see a class of optical illusions, Serre is building on this model with the goal of improving artificial vision.

State-of-the-art artificial vision algorithms, such as those used to tag faces or recognize stop signs, have trouble seeing context, he noted. By including horizontal connections tuned by context-dependent optical illusions, he hopes to address this weakness.

Perhaps visual deep learning programs that take context into account will be harder to fool. A certain sticker, when stuck on a stop sign can trick an artificial vision system into thinking it is a 65-mile-per-hour speed limit sign, which is dangerous, Serre said.

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Researchers teach computers to see optical illusions

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By making a neural-network computer model that can be fooled by optical illusions like humans, the researchers advanced knowledge of the human visual system and may help improve artificial vision.

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Scientists have developed a human-friendly, ultra-flexible organic sensor powered by sunlight, which acts as a self-powered heart monitor. Previously, they developed a flexible photovoltaic cell that could be incorporated into textiles. In this study, they directly integrated a sensory device, called an organic electrochemical transistor -- a type of electronic device that can be used to measure a variety of biological functions -- into a flexible organic solar cell. Using it, they were then able to measure the heartbeats of rats and humans under bright light conditions.

Self-powered devices that can be fit directly on human skin or tissue have great potential for medical applications. They could be used as physiological sensors for the real-time monitoring of heart or brain function in the human body. However, practical realization has been impractical due to the bulkiness of batteries and insufficient power supply, or due to noise interference from the electrical supply, impeding conformability and long-term operation.

The key requirement for such devices is a stable and adequate energy supply. A key advance in this study, published in Nature, is the use of a nano-grating surface on the light absorbers of the solar cell, allowing for high photo-conversion efficiency (PCE) and light angle independency. Thanks to this, the researchers were able to achieve a PCE of 10.5 percent and a high power-per-weight ratio of 11.46 watts per gram, approaching the "magic number" of 15 percent that will make organic photovoltaics competitive with their silicon-based counterparts. They demonstrated a PCE decrease of only 25 percent (from 9.82% to 7.33%) under repetitive compression test (900 cycles) and a higher PCE gain of 45 percent compared to non-grating devices under 60 degree light angle.

To demonstrate a practical application, sensory devices called organic electrochemical transistors were integrated with organic solar cells on an ultra-thin (1 ?m) substrate, to allow the self-powered detection of heartbeats either on the skin or to record electrocardiographic (ECG) signals directly on the heart of a rat. They found that the device worked well at a lighting level of 10,000 lux, which is equivalent to the light seen when one is in the shade on a clear sunny day, and experienced less noise than similar devices connected to a battery, presumably because of the lack of electric wires.

According to Kenjiro Fukuda of the RIKEN Center for Emergent Matter Science, "This is a nice step forward in the quest to make self-powered medical monitoring devices that can be placed on human tissue. There are some important remaining tasks, such as the development of flexible power storage devices, and we will continue to collaborate with other groups to produce practical devices. Importantly, for the current experiments we worked on the analog part of our device, which powers the device and conducts the measurement. There is also a digital silicon-based portion, for the transmission of data, and further work in that area will also help to make such devices practical." The research was carried out by RIKEN in collaboration with researchers from the University of Tokyo.

Journal Reference:

Sungjun Park, Soo Won Heo, Wonryung Lee, Daishi Inoue, Zhi Jiang, Kilho Yu, Hiroaki Jinno, Daisuke Hashizume, Masaki Sekino, Tomoyuki Yokota, Kenjiro Fukuda, Keisuke Tajima, Takao Someya. Self-powered ultra-flexible electronics via nano-grating-patterned organic photovoltaics. Nature, 2018; 561 (7724): 516 DOI: 10.1038/s41586-018-0536-x

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medical devices; heart disease; diseases and conditions; electronics; technology; graphene; spintronics research; mobile computing; neural interfaces

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A self-powered heart monitor taped to the skin

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Scientists have developed a human-friendly, ultra-flexible organic sensor powered by sunlight, which acts as a self-powered heart monitor. In this study, they directly integrated a sensory device, called an organic electrochemical transistor -- a type of electronic device that can be used to measure a variety of biological functions -- into a flexible organic solar cell.

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from research organizations

Is there a second Earth out there in space? Our knowledge of planetary systems far, far away is increasing constantly, as new technologies continue to sharpen our gaze into space. To date, 3,700 planets have already been discovered outside our solar system. The planetary masses and radii of these exoplanets can be used to infer their mean density, but not their exact chemical composition and structure. The intriguing question about what these planets could look like is thus still open.

"Theoretically, we can assume various compositions, such as a world of pure water, a world of pure rock, and planets that have hydrogen-helium atmospheres and explore what radii are expected" explains Michael Lozovsky, a doctoral candidate in the group of Prof. Ravit Helled at the Institute for Computational Science at the University of Zurich.
Thresholds for planetary composition
Lozovsky and collaborators have used databases and statistical tools to characterize exoplanets and their atmospheres. These are fairly common and surrounded by a volatile layer of hydrogen and helium. However, the directly measured data previously didn't allow the researchers to determine the exact structure, since different compositions may lead to the same mass and radius. In addition to the accuracy of the data relating to mass and radius, the research team thus also investigated the assumed internal structure, temperature and reflected radiation in 83 of the 3,700 known planets, for which the masses and radii are well-determined.

"We used a statistical analysis to set limits on possible compositions. Using a database of detected exoplanets, we found that every theoretical planetary structure has a 'threshold radius', a planetary radius above which no planets of this composition exist," explains Michael Lozovsky. The amount of elements in the gaseous layer that are heavier than helium, the percentage of hydrogen and helium, as well as the distribution of elements in the atmosphere are important factors in determining the threshold radius.
Super-Earths and mini-Neptunes
The researchers from the Institute for Computational Science found that planets with a radius of up to 1.4 times that of Earth (6,371 kilometers) can be earth-like, i.e. they have a composition similar to Earth. Planets with radii above this threshold have a higher share of silicates or other light materials. Most of the planets with a radius above 1.6 radii of the Earth must have a layer of hydrogen-helium gas or water in addition to their rocky core, while those larger than 2.6 Earth radii can't be water worlds and therefore might be surrounded by an atmosphere. Planets with radii larger than 4 Earth radii are expected to be very gaseous and consist of at least 10 percent hydrogen and helium, similarly to Uranus and Neptune.

The findings of the study provide new insights into the development and diversity of these planets. One particularly interesting threshold concerns the difference between large terrestrial-like planets -- otherwise known as super-Earths -- and small gaseous planets, also referred to as mini-Neptunes. According to the researchers, this threshold lies at a radius of three times that of Earth. Below this threshold, it is therefore possible to find earth-like planets in the vast expanse of the galaxy.

Journal Reference:

M. Lozovsky, R. Helled, C. Dorn, J. Venturini. Threshold Radii of Volatile-rich Planets. The Astrophysical Journal, 2018; 866 (1): 49 DOI: 10.3847/1538-4357/aadd09

Cite This Page:

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extrasolar planets; pluto; kuiper belt; asteroids

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comets and meteors; astrophysics; satellites; nebulae; solar system

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Researchers have analyzed the composition and structure of faraway exoplanets using statistical tools. Their analysis indicates whether a planet is earth-like, made up of pure rock or a water-world. The larger the planet, the more hydrogen and helium surround it.

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This image, taken with the Wide Field Planetary Camera 2 on board the NASA/ESA Hubble Space Telescope, shows the galaxy NGC 6052, located around 230 million light-years away in the constellation of Hercules.

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jeremy roos

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Scientists are uncovering the secrets of tapeworms that can live in the human brain.

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Mercury is small, fast and close to the sun, making the rocky world challenging to visit. Only one probe has ever orbited the planet and collected enough data to tell scientists about the chemistry and landscape of Mercury's surface. Learning about what is beneath the surface, however, requires careful estimation.

After the probe's mission ended in 2015, planetary scientists estimated Mercury's crust was roughly 22 miles thick. One University of Arizona scientist disagrees.

Using the most recent mathematical formulas, Lunar and Planetary Laboratory associate staff scientist Michael Sori estimates that the Mercurial crust is just 16 miles thick and is denser than aluminum. His study, "A Thin, Dense Crust for Mercury," will be published May 1 in Earth and Planetary Science Letters and is currently available online.

Sori determined the density of Mercury's crust using data collected by the Mercury Surface, Space Environment and Geochemistry Ranging (MESSENGER) spacecraft. He created his estimate using a formula developed by Isamu Matsuyama, a professor in the Lunar and Planetary Laboratory, and University of California Berkeley scientist Douglas Hemingway.

Sori's estimate supports the theory that Mercury's crust formed largely through volcanic activity. Understanding how the crust was formed may allow scientists to understand the formation of the entire oddly structured planet.

"Of the terrestrial planets, Mercury has the biggest core relative to its size," Sori said.

Mercury's core is believed to occupy 60 percent of the planet's entire volume. For comparison, Earth's core takes up roughly 15 percent of its volume. Why is Mercury's core so large?

"Maybe it formed closer to a normal planet and maybe a lot of the crust and mantle got stripped away by giant impacts," Sori said. "Another idea is that maybe, when you're forming so close to the sun, the solar winds blow away a lot of the rock and you get a large core size very early on. There's not an answer that everyone agrees to yet."

Sori's work may help point scientists in the right direction. Already, it has solved a problem regarding the rocks in Mercury's crust.
Mercury's Mysterious Rocks
When the planets and Earth's moon formed, their crusts were born from their mantles, the layer between a planet's core and crust that oozes and flows over the course of millions of years. The volume of a planet's crust represents the percentage of mantle that was turned into rocks.

Before Sori's study, estimates of the thickness of Mercury's crust led scientists to believe 11 percent of the planet's original mantle had been turned into rocks in the crust. For the Earth's moon -- the celestial body closest in size to Mercury -- the number is lower, near 7 percent.

"The two bodies formed their crusts in very different ways, so it wasn't necessarily alarming that they didn't have the exact same percentage of rocks in their crust," Sori said.

The moon's crust formed when less dense minerals floated to the surface of an ocean of liquid rock that became the body's mantle. At the top of the magma ocean, the moon's buoyant minerals cooled and hardened into a "flotation crust." Eons of volcanic eruptions coated Mercury's surface and created its "magmatic crust."

Explaining why Mercury created more rocks than the moon did was a scientific mystery no one had solved. Now, the case can be closed, as Sori's study places the percentage of rocks in Mercury's crust at 7 percent. Mercury is no better than the moon at making rocks.

Sori solved the mystery by estimating the crust's depth and density, which meant he had to find out what kind of isostasy supported Mercury's crust.
Determining Density and Depth
The most natural shape for a planetary body to take is a smooth sphere, where all points on the surface are an equal distance from the planet's core. Isostasy describes how mountains, valleys and hills are supported and kept from flattening into smooth plains.

There are two main types isostasy: Pratt and Airy. Both focus on balancing the masses of equally sized slices of the planet. If the mass in one slice is much greater than the mass in a slice next to it, the planet's mantle will ooze, shifting the crust on top of it until the masses of every slice are equal.

Pratt isostasy states that a planet's crust varies in density. A slice of the planet that contains a mountain has the same mass as a slice that contains flat land, because the crust that makes the mountain is less dense than the crust that makes flat land. In all points of the planet, the bottom of the crust floats evenly on the mantle.

Until Sori completed his study, no scientist had explained why Pratt isostasy would or wouldn't support Mercury's landscape. To test it, Sori needed to relate the planet's density to its topography. Scientists had already constructed a topographic map of Mercury using data from MESSENGER, but a map of density didn't exist. So Sori made his own using MESSENGER's data about the elements found on Mercury's surface.

"We know what minerals usually form rocks, and we know what elements each of these minerals contain. We can intelligently divide all the chemical abundances into a list of minerals," Sori said of the process he used to determine the location and abundance of minerals on the surface. "We know the densities of each of these minerals. We add them all up, and we get a map of density."

Sori then compared his density map with the topographic map. If Pratt isostasy could explain Mercury's landscape, Sori expected to find high-density minerals in craters and low-density minerals in mountains; however, he found no such relationship. On Mercury, minerals of high and low density are found in mountains and craters alike.

With Pratt isostasy disproven, Sori considered Airy isostasy, which has been used to make estimates of Mercury's crustal thickness. Airy isostasy states that the depth of a planet's crust varies depending on the topography.

"If you see a mountain on the surface, it can be supported by a root beneath it," Sori said, likening it to an iceberg floating on water.

The tip of an iceberg is supported by a mass of ice that protrudes deep underwater. The iceberg contains the same mass as the water it displaces. Similarly, a mountain and its root will contain the same mass as the mantle material being displaced. In craters, the crust is thin, and the mantle is closer to the surface. A wedge of the planet containing a mountain would have the same mass as a wedge containing a crater.

"These arguments work in two dimensions, but when you account for spherical geometry, the formula doesn't exactly work out," Sori said.

The formula recently developed by Matsuyama and Hemingway, though, does work for spherical bodies like planets. Instead of balancing the masses of the crust and mantle, the formula balances the pressure the crust exerts on the mantle, providing a more accurate estimate of crustal thickness.

Sori used his estimates of the crust's density and Hemingway and Matsuyama's formula to find the crust's thickness. Sori is confident his estimate of Mercury's crustal thickness in its northern hemisphere will not be disproven, even if new data about Mercury is collected. He does not share this confidence about Mercury's crustal density.

MESSENGER collected much more data on the northern hemisphere than the southern, and Sori predicts the average density of the planet's surface will change when density data is collected over the entire planet. He already sees the need for a follow-up study in the future.

The next mission to Mercury will arrive at the planet in 2025. In the meantime, scientists will continue to use MESSENGER data and mathematical formulas to learn everything they can about the first rock from the sun.

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mercury; solar system; moon; extrasolar planets; jupiter; eris (xena); kuiper belt; pluto

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Mercury's thin, dense crust: Mercury's crust is thinner than anyone thought, new mathematical calculations reveal

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Mercury is small, fast and close to the sun, making the rocky world challenging to visit. Only one probe has ever orbited the planet and collected enough data to tell scientists about the chemistry and landscape of Mercury's surface. Learning about what is beneath the surface, however, requires careful estimation.

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An illustration of the Large Hadron Collider, the world's largest particle accelerator, in Switzerland.

Credit: Daniel Dominguez; Maximilien Brice/CERN

The future could be glorious or grim, and the gust of wind that tips things one way or another is us - the humans of the 21st century.

"The stakes are very high this century," said British cosmologist Martin Rees. "It's the first century when human beings ... can determine the planet's future." [ 10 Technologies That Will Transform Your Life]

For the past couple of days, news outlets have been reporting that Rees' new book "On the Future: Prospects for Humanity" (Princeton University Press, 2018) makes a rather spectacular claim: If things go wrong, particle accelerators that slam subatomic particles together at immense speeds - like the Large Hadron Collider near Geneva, Switzerland,- could turn Earth into a dense sphere or black hole.

In fact, Rees told Live Science in a recent interview, his book claims the opposite: The probability of this happening is very, very low. The idea of the LHC forming mini-black holes has been circulating for a while and is not something to worry about, he said.

"I think people quite rightly thought about this question before they did the experiments, but they were reassured," he said. The reassurance mainly comes from the fact that nature already performs such experiments - to an extreme.

Cosmic rays, or particles with much higher energies than those created in particle accelerators, frequently collide in the galaxy, and haven't yet done anything disastrous like rip space apart, Rees said.

"It's not stupid to think about these things, but on the other hand, they're not serious worries," he said. But in contrast, "if you're doing something where you have no guidance from nature, then you've got to be a bit careful."

It's in these cases that technology can be a realistic threat for the future, he said.

Gene editing, for example, can yield new organic products that don't exist in nature, Rees said.

Sometimes, if "you tinker with a virus, then of course you can't be quite sure what the consequences are," he said. "It may well be that you can create a form of a virus which has not arisen through natural mutations."

There's much conversation around gene drives, for example - modifications that are being considered for mosquitoes to reduce disease transmission. Gene drives essentially tweak the genetic code to alter the likelihood of inheriting certain traits, and can lead to "unpredictable environmental effects," he said.

Technology is also making it easier for one person's actions to have far-reaching consequences, he said.

"Just a few people anywhere in the world can cause something which has global consequences in a way they couldn't [before]," Rees said. One example is a cyberattack.

Technology also does incredible things, especially in medicine and space travel. And as such, "things can go extremely well," Rees said. "But there are all these hazards along the way because of misuse of technologies."

The second major threat to the future is our collective influence on the climate, environment and biodiversity, he said. So, it's important to have international conversations about how to combat the pressures humanity has placed on the world, he added. And it's much easier to solve the world's problems, such as by combating climate change, than by packing up our things and going to a new planet, he said.

"It's a dangerous illusion to think that we can escape the world's problems by going to Mars," Rees said. In fact, robots - who will likely be better-adapted to space travel than humans - will mostly be the ones exploring the cosmos. [ Super-Intelligent Machines: 7 Robotic Futures]

Rees doesn't think robots are truly a threat for the future.

"I don't worry as much as some people do about AI taking over," Rees said. Humans evolved from earlier primates because of natural selection, and the traits that were favored were intelligence and aggression, he said. Electronics "are not engaged in a struggle for survival as in Darwinian selection, so there's no reason why they should be aggressive," he said.

For that reason, they probably won't kill off the human race and expand into the universe. That would be too "anthropomorphic" of them, he said. "They might just want to sit and think," he said.

Originally published on Live Science.

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No, Particle Accelerators Will Not Destroy the Planet, But Humans Might

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The future could be glorious or grim, and the gust of wind that tips things one way or another is us - the humans of the 21st century. "The stakes are very high this century," said British cosmologist Martin Rees. "It's the first century when human beings ...

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Palaeopascichnus linearis, which resembles a chain of fossilized poop, is the earliest macroscopic creature found with an exoskeleton. Figures B and C show magnified images of the exoskeletons of sediment the creatures cemented to themselves with their own excretions.

Credit: nton Kolesnikov

Mysterious fossils found all over the world belong to creatures that built their own skeletons more than 550 million years ago.

Palaeopascichnus linearis is among the world's oldest skeletal creatures, according to new research published in the October issue of the journal Precambrian Research. These tiny globular, ocean bottom-dwellers may have been amoeba-like creatures that accrued bits of sand and sediment around themselves to create their own exoskeleton. All earlier organisms with similar exoskeletons were much, much smaller, said study leader Anton Kolesnikov, a paleontologist at the Institute of Petroleum Geology and Geophysics at the Siberian Branch of the Russian Academy of Sciences and the University of Lille in France. [ In Images: The Oldest Fossils on Earth]

"It is the oldest known macroscopic skeletal organism," Kolesnikov said of P. linearis.

Palaeopascichnus fossils are found the world over in rocks from the Ediacaran period, which spanned from 635 million to 541 million years ago. No one had been able to agree on exactly what the fossils were, though, Kolesnikov wrote in an email to Live Science. Some thought they were trace fossils left behind by some organism shuffling along the seafloor. Others suspected they were coprolites - fossilized poop. Still others argued they were organisms in and of themselves.

Figuring out the answer was difficult because many areas where Ediacaran fossils are found around the world are protected, Kolesnikov said. But in the Olenek Uplift of northeastern Siberia, past the Arctic Circle, Kolesnikov and his colleagues discovered sites where they collected more than 300 new specimens of the fossils. They also discovered more fossils from the area in collections dating back to the 1980s.

"Huge amounts of fossils from Siberia allowed us to experiment with thin sampling, sectioning, cutting, studying in [electron] microscopes" and more, Kolesnikov said.

This analysis revealed that the fossils were made up of chains of between two and 40 spherical or oval modules, each between 0.04 inches and 0.2 inches (1 and 5 millimeters) in diameter. Each module was bordered by a fine rim of sediment.

More than anything, the researchers reported, the fossils looked like today's xenophyophores, which are giant foraminifera. These bizarre creatures are amoebas that protect themselves with "agglutinated tests," or exoskeletons of sediment they cement to themselves with their own excretions. Scientists reporting in a March 2018 paper in the Zoological Journal detailed the discovery of a new species of these xenophyophores, Aschemonella monile, which look remarkably similar to the fossil versions from Siberia.

The oldest microorganisms with agglutinized skeletons date back to about 742 million years ago, the researchers wrote in their new study. But P. linearis, which dates back to around 613 million to 544 million years ago, may be the oldest non-microscopic organism to boast a skeleton. Previously, Kolesnikov said, macroscopic organisms (those visible to the naked eye) weren't thought to evolve skeletons until the Paleozoic. The new findings suggest this happened slightly before that, in the late Proterozoic.

Original article on Live Science.

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Petrified Chains of 'Poop' Turn Out to Be One of Earth's Oldest Skeletons

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Mysterious fossils found all over the world belong to creatures that built their own skeletons more than 550 million years ago. Palaeopascichnus linearis is among the world's oldest skeletal creatures, according to new research published in the October issue of the journal Precambrian Research.

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Human evolution used to be depicted as a straight line, gradually progressing from an ape-like ancestor to modern Homo sapiens. But thanks to next-generation sequencing -- as well as the discovery of genetic material from extinct subspecies of early humans -- findings in recent years have shown that it wasn't quite so orderly. The human family tree is full of twists and branches that helped shape what we are today. Now, a study published in the journal Cell is reporting new details about the role of viruses in shaping evolution, in particular viral interactions between modern humans and Neanderthals.

"It's not a stretch to imagine that when modern humans met up with Neanderthals, they infected each other with pathogens that came from their respective environments," says first author David Enard (@DavidEnard), an assistant professor in ecology and evolutionary biology at the University of Arizona. "By interbreeding with each other, they also passed along genetic adaptations to cope with some of those pathogens."

Current thinking is that modern humans began moving out of Africa and into Eurasia about 70,000 years ago. When they arrived, they met up with Neanderthals who, along with their own ancestors, had been adapting to that geographic area for hundreds of thousands of years. The Eurasian environment shaped Neanderthals' evolution, including the development of adaptations to viruses and other pathogens that were present there but not in Africa.

The Cell study provides new details about the role of adaptive introgression, or hybridization between species, in human evolution. "Some of the Neanderthals had adaptive mutations that gave them advantages against these pathogens, and they were able to pass some of these mutations on to modern humans," explains Enard, who completed the work while he was a postdoctoral researcher at Stanford University. "That's called positive natural selection -- it favors certain individuals that carry these advantageous mutations."

Enard and Dmitri Petrov (@PetrovADmitri), the Michelle and Kevin Douglas Professor of Biology at Stanford University and senior author of the new study, use bioinformatics tools to study global patterns of evolution across tens of thousands of years. Their earlier research focused on how viruses impacted the evolution of humans. In 2016, they reported that about one-third of protein adaptations since humans split from other great apes was driven by a response to infectious viruses. The new work built on those findings looked at which of those adaptations may have come from Neanderthals.

In the current study, the investigators annotated thousands of genes in the human genome that are known to interact with pathogens -- more than 4,000 of the 25,000 total genes. "We focused on these genes because the ones that interact with viruses are much more likely to have been involved in adaptation against infectious disease compared with genes that don't have anything to do with viruses," Enard says.

They then looked at whether there was an enrichment of stretches of Neanderthal DNA in those 4,000 genes. Earlier studies from other groups have shown that Neanderthal DNA is present in humans. Those sequences are publicly available to investigators in the field. Based on the analysis, Enard and Petrov found strong evidence that adaptive genes that provided resistance against viruses were shared between Neanderthals and modern humans.

"Many Neanderthal sequences have been lost in modern humans, but some stayed and appear to have quickly increased to high frequencies at the time of contact, suggestive of their selective benefits at that time," Petrov says. "Our research aims to understand why that was the case. We believe that resistance to specific RNA viruses provided by these Neanderthal sequences was likely a big part of the reason for their selective benefits."

"One of the things that population geneticists have wondered about is why we have maintained these stretches of Neanderthal DNA in our own genomes," Enard adds. "This study suggests that one of the roles of those genes was to provide us with some protection against pathogens as we moved into new environments."

In addition to revealing new details about human evolution, Enard notes, another benefit of this type of research is that it will help investigators uncover new clues about ancient disease outbreaks. This could potentially inform better ways to monitor for and treat future epidemics. "RNA is very fragile and gets degraded fast, so it's hard to learn much about ancient diseases that were caused by RNA-based viruses," he says. "You can think of these genetic adaptations like footprints from long-extinct dinosaurs preserved in fossilized mud. Even without having access to the viruses themselves, scientists who study prehistoric epidemics will be able to learn about the pathogens that drove them."

This research was funded by the National Institutes of Health.

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genes; human biology; viruses; microbes and more; evolutionary biology; biology; early humans; human evolution; evolution

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Viruses influenced gene sharing between Neanderthals and humans

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Human evolution used to be depicted as a straight line, gradually progressing from an ape-like ancestor to modern Homo sapiens. But thanks to next-generation sequencing, findings in recent years have shown that it wasn't quite so orderly. Now, a new study is reporting new details about the role of viruses in shaping evolution, in particular viral interactions between modern humans and Neanderthals.

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Electricity

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Contributors: jimblom

Getting Started

Electricity is all around us--powering technology like our cell phones, computers, lights, soldering irons, and air conditioners. It's tough to escape it in our modern world. Even when you try to escape electricity, it's still at work throughout nature, from the lightning in a thunderstorm to the synapses inside our body. But what exactly is electricity? This is a very complicated question, and as you dig deeper and ask more questions, there really is not a definitive answer, only abstract representations of how electricity interacts with our surroundings.

Electricity is a natural phenomenon that occurs throughout nature and takes many different forms. In this tutorial we'll focus on current electricity: the stuff that powers our electronic gadgets. Our goal is to understand how electricity flows from a power source through wires, lighting up LEDs, spinning motors, and powering our communication devices.

Electricity is briefly defined as the flow of electric charge, but there's so much behind that simple statement. Where do the charges come from? How do we move them? Where do they move to? How does an electric charge cause mechanical motion or make things light up? So many questions! To begin to explain what electricity is we need to zoom way in, beyond the matter and molecules, to the atoms that make up everything we interact with in life.

This tutorial builds on some basic understanding of physics, force, energy, atoms, and [fields](http://en.wikipedia.org/wiki/Field_(physics)) in particular. We'll gloss over the basics of each of those physics concepts, but it may help to consult other sources as well.

Going Atomic

To understand the fundamentals of electricity, we need to begin by focusing in on atoms, one of the basic building blocks of life and matter. Atoms exist in over a hundred different forms as chemical elements like hydrogen, carbon, oxygen, and copper. Atoms of many types can combine to make molecules, which build the matter we can physically see and touch.

Atoms are tiny, stretching at a max to about 300 picometers long (that's 3x10⁻¹⁰ or 0.0000000003 meters). A copper penny (if it actually were made of 100% copper) would have 3.2x10 ²² atoms (32,000,000,000,000,000,000,000 atoms) of copper inside it.

Even the atom isn't small enough to explain the workings of electricity. We need to dive down one more level and look in on the building blocks of atoms: protons, neutrons, and electrons.

Building Blocks of Atoms

An atom is built with a combination of three distinct particles: electrons, protons, and neutrons. Each atom has a center nucleus, where the protons and neutrons are densely packed together. Surrounding the nucleus are a group of orbiting electrons.

A very simple atom model. It's not to scale but helpful for understanding how an atom is built. A core nucleus of protons and neutrons is surrounded by orbiting electrons.

Every atom must have at least one proton in it. The number of protons in an atom is important, because it defines what chemical element the atom represents. For example, an atom with just one proton is hydrogen, an atom with 29 protons is copper, and an atom with 94 protons is plutonium. This count of protons is called the atom's atomic number.

The proton's nucleus-partner, neutrons, serve an important purpose; they keep the protons in the nucleus and determine the isotope of an atom. They're not critical to our understanding of electricity, so let's not worry about them for this tutorial.

Electrons are critical to the workings of electricity (notice a common theme in their names?) In its most stable, balanced state, an atom will have the same number of electrons as protons. As in the Bohr atom model below, a nucleus with 29 protons (making it a copper atom) is surrounded by an equal number of electrons.

As our understanding of atoms has evolved, so too has our method for modeling them. The Bohr model is a very useful atom model as we explore electricity.

The atom's electrons aren't all forever bound to the atom. The electrons on the outer orbit of the atom are called valence electrons. With enough outside force, a valence electron can escape orbit of the atom and become free. Free electrons allow us to move charge, which is what electricity is all about. Speaking of charge...

Flowing Charges

As we mentioned at the beginning of this tutorial, electricity is defined as the flow of electric charge. Charge is a property of matter--just like mass, volume, or density. It is measurable. Just as you can quantify how much mass something has, you can measure how much charge it has. The key concept with charge is that it can come in two types: positive (+) or negative (-).

In order to move charge we need charge carriers, and that's where our knowledge of atomic particles--specifically electrons and protons--comes in handy. Electrons always carry a negative charge, while protons are always positively charged. Neutrons (true to their name) are neutral, they have no charge. Both electrons and protons carry the same amount of charge, just a different type.

A lithium atom (3 protons) model with the charges labeled.

The charge of electrons and protons is important, because it provides us the means to exert a force on them. Electrostatic force!

Electrostatic Force

Electrostatic force (also called Coulomb's law) is a force that operates between charges. It states that charges of the same type repel each other, while charges of opposite types are attracted together. Opposites attract, and likes repel.

The amount of force acting on two charges depends on how far they are from each other. The closer two charges get, the greater the force (either pushing together, or pulling away) becomes.

Thanks to electrostatic force, electrons will push away other electrons and be attracted to protons. This force is part of the "glue" that holds atoms together, but it's also the tool we need to make electrons (and charges) flow!

Making Charges Flow

We now have all the tools to make charges flow. Electrons in atoms can act as our charge carrier, because every electron carries a negative charge. If we can free an electron from an atom and force it to move, we can create electricity.

Consider the atomic model of a copper atom, one of the preferred elemental sources for charge flow. In its balanced state, copper has 29 protons in its nucleus and an equal number of electrons orbiting around it. Electrons orbit at varying distances from the nucleus of the atom. Electrons closer to the nucleus feel a much stronger attraction to the center than those in distant orbits. The outermost electrons of an atom are called the valence electrons, these require the least amount of force to be freed from an atom.

This is a copper atom diagram: 29 protons in the nucleus, surrounded by bands of circling electrons. Electrons closer to the nucleus are hard to remove while the valence (outer ring) electron requires relatively little energy to be ejected from the atom.

Using enough electrostatic force on the valence electron--either pushing it with another negative charge or attracting it with a positive charge--we can eject the electron from orbit around the atom creating a free electron.

Now consider a copper wire: matter filled with countless copper atoms. As our free electron is floating in a space between atoms, it's pulled and prodded by surrounding charges in that space. In this chaos the free electron eventually finds a new atom to latch on to; in doing so, the negative charge of that electron ejects another valence electron from the atom. Now a new electron is drifting through free space looking to do the same thing. This chain effect can continue on and on to create a flow of electrons called electric current.

A very simplified model of charges flowing through atoms to make current.

Conductivity

Some elemental types of atoms are better than others at releasing their electrons. To get the best possible electron flow we want to use atoms which don't hold very tightly to their valence electrons. An element's conductivity measures how tightly bound an electron is to an atom.

Elements with high conductivity, which have very mobile electrons, are called conductors. These are the types of materials we want to use to make wires and other components which aid in electron flow. Metals like copper, silver, and gold are usually our top choices for good conductors.

Elements with low conductivity are called insulators. Insulators serve a very important purpose: they prevent the flow of electrons. Popular insulators include glass, rubber, plastic, and air.

Static or Current Electricity

Before we get much further, let's discuss the two forms electricity can take: static or current. In working with electronics, current electricity will be much more common, but static electricity is important to understand as well.

Static Electricity

Static electricity exists when there is a build-up of opposite charges on objects separated by an insulator. Static (as in "at rest") electricity exists until the two groups of opposite charges can find a path between each other to balance the system out.

When the charges do find a means of equalizing, a static discharge occurs. The attraction of the charges becomes so great that they can flow through even the best of insulators (air, glass, plastic, rubber, etc.). Static discharges can be harmful depending on what medium the charges travel through and to what surfaces the charges are transferring. Charges equalizing through an air gap can result in a visible shock as the traveling electrons collide with electrons in the air, which become excited and release energy in the form of light.

Spark gap igniters are used to create a controlled static discharge. Opposite charges build up on each of the conductors until their attraction is so great charges can flow through the air.

One of the most dramatic examples of static discharge is lightning. When a cloud system gathers enough charge relative to either another group of clouds or the earth's ground, the charges will try to equalize. As the cloud discharges, massive quantities of positive (or sometimes negative) charges run through the air from ground to cloud causing the visible effect we're all familiar with.

Static electricity also familiarly exists when we rub balloons on our head to make our hair stand up, or when we shuffle on the floor with fuzzy slippers and shock the family cat (accidentally, of course). In each case, friction from rubbing different types of materials transfers electrons. The object losing electrons becomes positively charged, while the object gaining electrons becomes negatively charged. The two objects become attracted to each other until they can find a way to equalize.

Working with electronics, we generally don't have to deal with static electricity. When we do, we're usually trying to protect our sensitive electronic components from being subjected to a static discharge. Preventative measures against static electricity include wearing ESD (electrostatic discharge) wrist straps, or adding special components in circuits to protect against very high spikes of charge.

Current Electricity

Current electricity is the form of electricity which makes all of our electronic gizmos possible. This form of electricity exists when charges are able to constantly flow. As opposed to static electricity where charges gather and remain at rest, current electricity is dynamic, charges are always on the move. We'll be focusing on this form of electricity throughout the rest of the tutorial.

Circuits

In order to flow, current electricity requires a circuit: a closed, never-ending loop of conductive material. A circuit could be as simple as a conductive wire connected end-to-end, but useful circuits usually contain a mix of wire and other components which control the flow of electricity. The only rule when it comes to making circuits is they can't have any insulating gaps in them.

If you have a wire full of copper atoms and want to induce a flow of electrons through it, all free electrons need somewhere to flow in the same general direction. Copper is a great conductor, perfect for making charges flow. If a circuit of copper wire is broken, the charges can't flow through the air, which will also prevent any of the charges toward the middle from going anywhere.

On the other hand, if the wire were connected end-to-end, the electrons all have a neighboring atom and can all flow in the same general direction.

We now understand how electrons can flow, but how do we get them flowing in the first place? Then, once the electrons are flowing, how do they produce the energy required to illuminate light bulbs or spin motors? For that, we need to understand electric fields.

Electric Fields

We have a handle on how electrons flow through matter to create electricity. That's all there is to electricity. Well, almost all. Now we need a source to induce the flow of electrons. Most often that source of electron flow will come from an electric field.

What's a Field?

A field is a tool we use to model physical interactions which don't involve any observable contact. Fields can't be seen as they don't have a physical appearance, but the effect they have is very real.

We're all subconsciously familiar with one field in particular: Earth's gravitational field, the effect of a massive body attracting other bodies. Earth's gravitational field can be modeled with a set of vectors all pointing into the center of the planet; regardless of where you are on the surface, you'll feel the force pushing you towards it.

The strength or intensity of fields isn't uniform at all points in the field. The further you are from the source of the field the less effect the field has. The magnitude of Earth's gravitational field decreases as you get further away from the center of the planet.

As we go on to explore electric fields in particular remember how Earth's gravitational field works, both fields share many similarities. Gravitational fields exert a force on objects of mass, and electric fields exert a force on objects of charge.

Electric Fields

Electric fields (e-fields) are an important tool in understanding how electricity begins and continues to flow. Electric fields describe the pulling or pushing force in a space between charges. Compared to Earth's gravitational field, electric fields have one major difference: while Earth's field generally only attracts other objects of mass (since everything is so significantly less massive), electric fields push charges away just as often as they attract them.

The direction of electric fields is always defined as the direction a positive test charge would move if it was dropped in the field. The test charge has to be infinitely small, to keep its charge from influencing the field.

We can begin by constructing electric fields for solitary positive and negative charges. If you dropped a positive test charge near a negative charge, the test charge would be attracted towards the negative charge. So, for a single, negative charge we draw our electric field arrows pointing inward at all directions. That same test charge dropped near another positive charge would result in an outward repulsion, which means we draw arrows going out of the positive charge.

The electric fields of single charges. A negative charge has an inward electric field because it attracts positive charges. The positive charge has an outward electric field, pushing away like charges.

Groups of electric charges can be combined to make more complete electric fields.

The uniform e-field above points away from the positive charges, towards the negatives. Imagine a tiny positive test charge dropped in the e-field; it should follow the direction of the arrows. As we've seen, electricity usually involves the flow of electrons--negative charges--which flow against electric fields.

Electric fields provide us with the pushing force we need to induce current flow. An electric field in a circuit is like an electron pump: a large source of negative charges that can propel electrons, which will flow through the circuit towards the positive lump of charges.

Electric Potential (Energy)

When we harness electricity to power our circuits, gizmos, and gadgets, we're really transforming energy. Electronic circuits must be able to store energy and transfer it to other forms like heat, light, or motion. The stored energy of a circuit is called electric potential energy.

Energy? Potential Energy?

To understand potential energy we need to understand energy in general. Energy is defined as the ability of an object to do work on another object, which means moving that object some distance. Energy comes in many forms, some we can see (like mechanical) and others we can't (like chemical or electrical). Regardless of what form it's in, energy exists in one of two states: kinetic or potential.

An object has kinetic energy when it's in motion. The amount of kinetic energy an object has depends on its mass and speed. Potential energy, on the other hand, is a stored energy when an object is at rest. It describes how much work the object could do if set into motion. It's an energy we can generally control. When an object is set into motion, its potential energy transforms into kinetic energy.

Let's go back to using gravity as an example. A bowling ball sitting motionless at the top of Khalifa tower has a lot of potential (stored) energy. Once dropped, the ball--pulled by the gravitational field--accelerates towards the ground. As the ball accelerates, potential energy is converted into kinetic energy (the energy from motion). Eventually all of the ball's energy is converted from potential to kinetic, and then passed on to whatever it hits. When the ball is on the ground, it has a very low potential energy.

Electric Potential Energy

Just like mass in a gravitational field has gravitational potential energy, charges in an electric field have an electric potential energy. A charge's electric potential energy describes how much stored energy it has, when set into motion by an electrostatic force, that energy can become kinetic, and the charge can do work.

Like a bowling ball sitting at the top of a tower, a positive charge in close proximity to another positive charge has a high potential energy; left free to move, the charge would be repelled away from the like charge. A positive test charge placed near a negative charge would have low potential energy, analogous to the bowling ball on the ground.

To instill anything with potential energy, we have to do work by moving it over a distance. In the case of the bowling ball, the work comes from carrying it up 163 floors, against the field of gravity. Similarly, work must be done to push a positive charge against the arrows of an electric field (either towards another positive charge, or away from a negative charge). The further up the field the charge goes, the more work you have to do. Likewise, if you try to pull a negative charge away from a positive charge--against an electric field--you have to do work.

For any charge located in an electric field its electric potential energy depends on the type (positive or negative), amount of charge, and its position in the field. Electric potential energy is measured in units of joules ( J).

Electric Potential

Electric potential builds upon electric potential energy to help define how much energy is stored in electric fields. It's another concept which helps us model the behavior of electric fields. Electric potential is not the same thing as electric potential energy!

At any point in an electric field the electric potential is the amount of electric potential energy divided by the amount of charge at that point. It takes the charge quantity out of the equation and leaves us with an idea of how much potential energy specific areas of the electric field may provide. Electric potential comes in units of joules per coulomb ( J/C), which we define as a volt (V).

In any electric field there are two points of electric potential that are of significant interest to us. There's a point of high potential, where a positive charge would have the highest possible potential energy, and there's a point of low potential, where a charge would have the lowest possible potential energy.

One of the most common terms we discuss in evaluating electricity is voltage. A voltage is the difference in potential between two points in an electric field. Voltage gives us an idea of just how much pushing force an electric field has.

With potential and potential energy under our belt we have all of the ingredients necessary to make current electricity. Let's do it!

Electricity in Action!

After studying particle physics, field theory, and potential energy, we now know enough to make electricity flow. Let's make a circuit!

First we will review the ingredients we need to make electricity:

The definition of electricity is the flow of charge. Usually our charges will be carried by free-flowing electrons.

Negatively-charged electrons are loosely held to atoms of conductive materials. With a little push we can free electrons from atoms and get them to flow in a generally uniform direction.

A closed circuit of conductive material provides a path for electrons to continuously flow.

The charges are propelled by an electric field. We need a source of electric potential (voltage), which pushes electrons from a point of low potential energy to higher potential energy.

A Short Circuit

Batteries are common energy sources which convert chemical energy to electrical energy. They have two terminals, which connect to the rest of the circuit. On one terminal there are an excess of negative charges, while all of the positive charges coalesce on the other. This is an electric potential difference just waiting to act!

If we connected our wire full of conductive copper atoms to the battery, that electric field will influence the negatively-charged free electrons in the copper atoms. Simultaneously pushed by the negative terminal and pulled by the positive terminal, the electrons in the copper will move from atom to atom creating the flow of charge we know as electricity.

After a second of the current flow, the electrons have actually moved very little--fractions of a centimeter. However, the energy produced by the current flow is huge, especially since there's nothing in this circuit to slow down the flow or consume the energy. Connecting a pure conductor directly across an energy source is a bad idea. Energy moves very quickly through the system and is transformed into heat in the wire, which may quickly turn into melting wire or fire.

Illuminating a Light Bulb

Instead of wasting all that energy, not to mention destroying the battery and wire, let's build a circuit that does something useful! Generally an electric circuit will transfer electric energy into some other form--light, heat, motion, etc. If we connect a light bulb to the battery with wires in between, we have a simple, functional circuit.

Schematic: A battery (left) connecting to a lightbulb (right), the circuit is completed when the switch (top) closes. With the circuit closed, electrons can flow, pushed from the negative terminal of the battery through the lightbulb, to the positive terminal.

While the electrons move at a snails pace, the electric field affects the entire circuit almost instantly (we're talking speed of light fast). Electrons throughout the circuit, whether at the lowest potential, highest potential, or right next to the light bulb, are influenced by the electric field. When the switch closes and the electrons are subjected to the electric field, all electrons in the circuit start flowing at seemingly the same time. Those charges nearest the light bulb will take one step through the circuit and start transforming energy from electrical to light (or heat).

Resources and Going Further

In this tutorial we've uncovered just a tiny portion of the tip of the proverbial iceberg. There's still a ton of concepts left uncovered. From here we'd recommend you step right on over to our Voltage, Current, Resistance, and Ohm's Law tutorial. Now that you know all about electric fields (voltage) and flowing electrons (current), you're well on your way to understanding the law that governs their interaction.

For more information and visualizations explaining electricity, visit this site.

Here are some other beginner level concept tutorials we'd recommend reading through:

Or, maybe you'd like to learn something practical? In that case, check out some of these basic level skill tutorials:

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Contributors: jimblom Electricity is all around us--powering technology like our cell phones, computers, lights, soldering irons, and air conditioners. It's tough to escape it in our modern world. Even when you try to escape electricity, it's still at work throughout nature, from the lightning in a thunderstorm to the synapses inside our body.

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https://www.independent.co.uk/life-style/slime-toys-poisonous-chemicals-boron-parents-warning-which-a8450666.html

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A certified medical assistant in Corpus Christi, Texas, prepares a Gardasil shot.

Credit: Matthew Busch for The Washington Post via Getty Images

The U.S. Food and Drug Administration announced last week that Gardasil 9, the HPV vaccine, is now approved for use in people ages 27 to 45.

The vaccine, which protects against several strains of a sexually transmitted infection called human papillomavirus, has been on the market for 12 years; however, it was approved only for people ages 9 to 26. New research led the agency to expand the age range to 45, the FDA said in an Oct. 5 statement.

But does the new age approval mean that adults who never got the HPV vaccine should get one now? Not necessarily. [ 51 Facts About Sex]

To understand why that might be the case, it's important to understand what the vaccine can and cannot do. Gardasil 9, which is the version offered in the U.S., protects people from nine strains of HPV, seven of which can cause cancer in the cervix, vagina, anus, penis and throat, and two of which can cause genital warts. (The original version of the vaccine, simply called Gardasil, protected against the warts strains and two of the strains linked to cancer, the FDA said.)

All told, the vaccine prevents over 90 percent of possible HPV-caused cancers, said Gypsyamber D'Souza, an epidemiologist at the Bloomberg School of Public Health at Johns Hopkins University.

But here's the catch: The vaccine only works if the recipient hasn't had HPV before. If someone has already been exposed to a given strain of HPV - which a majority of reproductive-age Americans already have, according to the Centers for Disease Control and Prevention - the vaccine can't clear that infection, D'Souza told Live Science.

Still, because the vaccine protects against nine strains, if an adult hasn't previously been exposed to some of the other strains in the vaccine, it could protect against future infection with those strains.

Most HPV infections, including potentially cancer-causing varieties, go away on their own, the National Cancer Institute says. But about 33,700 people are diagnosed with HPV-induced cancers each year, the CDC says. And for those individuals whose infection would cause cancer, getting the vaccine before becoming sexually active can prevent their HPV encounters from turning into an infection and, eventually, leading to cancer, D'Souza said. Indeed, that's why the FDA approval and vaccine recommendations focused on younger, potentially less sexually active people in the past.

Generally, adults ages 27 to 45 are expected to have already been exposed to HPV, D'Souza said, because they're more likely to be in monogamous, long-term sexual relationships. Of course, not everyone in this age group is having low-risk sex, and now they have the option of getting the HPV vaccine. With the new research and approval of Gardasil 9 in this age group, the FDA is saying that the drug can still prevent HPV infections in these adults, D'Souza said.

The FDA announcement means that "it's approved for them because it's safe and will allow them to get vaccinated if they so desire," D'Souza said. "But we're going to need to look to our [medical] organizations that make recommendations about prevention and disease screening to review the data and understand whether the vaccine should be widely recommended for the age group."

Vaccines of any kind can have emotional and, depending on insurance coverage, financial costs. And while the HPV vaccine will not cause any harm, D'Souza said, medical organizations won't make any official recommendations until they have ample data showing the benefits of the vaccine for the entire age group. (Some of the organizations that will weigh in include the such as the American Society for Colposcopy and Cervical Pathology and the U.S. Preventive Services Task Force.)

Editor's note: This story was updated on Oct. 10 to clarify that, if a person has already been exposed to a particularly strain of the HPV virus before being vaccinated, the vaccine won't protect against that strain. However, it will protect against strains the person hasn't been exposed to.

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The HPV Vaccine Was Just Approved for Adults Up to Age 45. Should They Get It?

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The U.S. Food and Drug Administration announced last week that Gardasil 9, the HPV vaccine, is now approved for use in people ages 27 to 45. The vaccine, which protects against several strains of a sexually transmitted infection called human papillomavirus, has been on the market for 12 years; however, it was approved only for people ages 9 to 26.

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Political humorist Mark Russell once joked, "The scientific theory I like best is that the rings of Saturn are composed entirely of lost airline luggage."

Well, there's no luggage, it turns out. But a new study appearing in Science based on data from the final orbits last year of NASA's Cassini spacecraft shows the rings of Saturn -- some of the most visually stupendous objects in the universe -- are far more chemically complicated than previously was understood.

Furthermore, the paper shows the innermost D ring of the gas giant is hurling dust grains coated in its chemical cocktail into the planet's upper atmosphere at an extraordinary rate as it spins. Over long timescales, the researchers say this infalling material may change the carbon and oxygen content of the atmosphere.

"This is a new element of how our solar system works," said Thomas Cravens, professor of physics & astronomy at the University of Kansas and a co-author of the new paper. "Two things surprised me. One is the chemical complexity of what was coming off the rings -- we thought it would be almost entirely water based on what we saw in the past. The second thing is the sheer quantity of it -- a lot more than we originally expected. The quality and quantity of the materials the rings are putting into the atmosphere surprised me."

Cravens is a member of Cassini's Ion and Neutral Mass Spectrometer (INMS) team. During Cassini's "Grand Finale" plunge into Saturn's innermost ring and upper atmosphere in 2017, the mass spectrometer aboard the probe sampled chemicals at altitudes between Saturn's rings and atmosphere.

More than simply water, the INMS found the rings to be composed of water, methane, ammonia, carbon monoxide, molecular nitrogen and carbon dioxide.

"What the paper is describing is the environment in the gap between the inner ring and upper atmosphere, and some of the things found were expected, such as water," Cravens said. "What was a surprise was the mass spectrometer saw methane -- no one expected that. Also, it saw some carbon dioxide, which was unexpected. The rings were thought to be entirely water. But the innermost rings are fairly contaminated, as it turns out, with organic material caught up in ice."

A further new finding from Cassini's mass spectrometer showed large amounts of the chemical brew from Saturn's D ring is flung into the planet's upper atmosphere by the ring spinning faster than the planet's atmosphere itself.

"We saw it was happening even though it's not fully understood," the KU researcher said. "What we saw is this material, including some benzine, was altering the uppermost atmosphere of Saturn in the equatorial region. There were both grains and dust that were contaminated."

Cravens said the findings could cast new light on mechanisms underpinning our solar system as well as other solar systems and exoplanets -- and also prompt a host of new scientific questions.

"This could help us understand, how does a planet get rings? Some do, some don't," he said. "What's the lifetime of a ring? And what's replenishing the rings? Was there a time when Saturn didn't have rings? How did that composition get into there in the first place? Is it left over from the formation of our solar system? Does it date back to proto pre-solar nebula, the nebula that collapsed out of interstellar media that formed the sun and planets?"

According to Cravens, the higher-than-expected rate of material being expelled from Saturn's D Ring into the planet's upper atmosphere, or ionosphere, is sufficient that astronomers now think the lifespan of the ring may be briefer than previously estimated.

"Because of this data, we now have shortened the lifetime of inner rings because of the quantity of material being moved out -- it's much more than we thought before," Cravens said. We know that it's bumping material out of the rings at least 10 times faster than we thought. If it's not being replenished, the rings aren't going to last -- you've got a hole in your bucket. Jupiter probably had a ring that evolved into the current wispy ring, and it could be for similar reasons. Rings do come and go. At some point they gradually drain away unless somehow they're getting new material."

Assisted by KU graduate and undergraduate students, a first stage of Cravens' work involved sorting and cleaning raw data from Cassini's INMS instrument.

"The raw data came through from our instrument on Cassini to deep-space antennas to NASA's Jet Propulsion Laboratory and then to computers at the Southwest Research Institute in San Antonio where Hunter Waite, the first author, is based," he said.

But Cravens' main contribution involved interpreting that data with a focus on how materials from the rings are altering Saturn's ionosphere. Cravens and his colleagues report the influx of chemicals from the rings change Saturn's equatorial ionospheric chemistry by converting the hydrogen ions and triatomic hydrogen ions into heavier molecular ions, depleting the planet's ionospheric density.

"My interest was in the ionosphere, the charged-particle environment, and that's what I focused on," Cravens said. "This gunk coming in chews up a lot of the ionosphere, affects its composition and causes observable effects -- that's what we're trying to understand now. The data are clear, but explanations are still being modeled and that will take a while. The material is coming into Saturn at high speeds because the rings are moving faster than the atmosphere quite a bit. It doesn't just drop in gently. It comes flying in there like a satellite re-entering our own planet. These dust grains moving at satellite speed, depositing energy that can dissociate the atmosphere. Per atom, it's pretty energetic stuff because of the speed differentiation between the rings and the atmosphere. We think it may be heating the upper atmosphere, changing its composition."

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saturn; solar system; astronomy; mars; extrasolar planets; space probes; astrophysics; pluto

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Surprising chemical complexity of Saturn's rings changing planet's upper atmosphere

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A new study based on data from the final orbits last year of NASA's Cassini spacecraft shows the rings of Saturn -- some of the most visually stupendous objects in the universe -- are far more chemically complicated than previously was understood.

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There is a ton of information regarding how deep is the ocean, or how big it is. But one question that people often forget to ask is, where do we figure in there?

How deep can we dive? How much of the ocean have we explored?

If you have ever wondered what our connection to the ocean deeps is, you're gonna love this infographic!

Embed How Deep Can We Dive on Your Site: Copy and Paste the Code Below

Here's a closer look at the ocean depth from the infographic:
1. The official scuba-diving limit is 100 meters (328ft)
Scuba diving is tricky. There are some inherent dangers because of the way gasses found in the air we breathe act at high pressures (air is mostly comprised of nitrogen, oxygen, and carbon-dioxide).

With every 10 meters under water, the pressure rises by one atmosphere, which means that at 50 meters the pressure is five times as high as it is on surface.

This isn't so much a problem for us, our bodies can take this if trained properly, but we can't breathe normal air at these depths due to the nitrogen narcosis and oxygen toxicity.

Narcosis is an effect similar to drowsiness or being slightly drunk, where inhaling gasses at high pressure can cause the slight change in our consciousness. Almost all gasses have this anesthetic effect, but at different pressures.

Most diving associations don't allow recreational divers to dive below 60 meters, and 66 meters is considered a limit for using compressed air. After that, special mixtures have to be used in order to prevent oxygen toxicity. These special mixtures substitute a part of oxygen, and even nitrogen, with helium.

When a diver reaches depths with relatively high pressures, the partial pressure of oxygen that we breathe in increases to a point where the oxygen penetrates the tissue of our eyes, lungs and nervous system, which in turn can cause vomiting, seizures, blindness, organ damage and failure, and death. In order to avoid these terrible consequences, we use special gas mixtures instead of normal compressed air, of which the most famous is the so called Trimix - a mixture of oxygen, helium and nitrogen.

These pressure issues are the reason why scuba divers have to take a lot of time when returning from the dives, in order to prevent oxygen toxicity damage, and decompression issues (which is sort of opposite to toxicity - gas bubbles are released from the tissue due to the rapid lowering of the pressure). It took some time to establish these limits, which naturally leads us to:
2. Maurice Fargues, the first scuba diving casualty, dived at 120 meters (390 ft)
It is fairly logical to conclude that scuba diving is by its nature very dangerous, and it especially was in the first half of the twentieth century when technology wasn't as developed as it is today, and some risk were still unknown. One of the men that unfortunately paid dearly to further our knowledge on this topic was a French diver, Maurice Fargues.

Fargues was a part of French Navy diving team, and he was an extremely adept diver who even saved two of his teammates from drowning on one of their diving missions. What he is most well known for, unfortunately, is his decision to establish what the safe scuba diving limit is. After several months of preparation, on September 17, 1947, Fargues made a dive off the coast of Toulon, where one of the French navy bases was located.

The plan was fairly simple:

He was going to dive down the anchored line which was marked at 10 meter intervals, and he would sign each marker as he passed it. He would occasionally have to tug on his safety line, so that his spotter on the surface, Frédéric Dumas, knows that everything is ok. After around 3 minutes into the dive, Maurice stopped signaling, and his teammates scrambled to rescue him. Dumas started pulling him up by his safety line, while a couple of divers dived in to meet him half-way at the depth of around 60 meters. When they reached him, they found him unconscious with his mouthpiece loose.

They quickly pulled him up and tried to resuscitate him, but after 12 hours without success, they had to proclaim him dead, to the great despair of Frédéric Duma and Jacques Cousteau, men whose life Fargues saved.

As Cousteau wrote in his book, "The Silent World":
"Dumas and I owed our lives to Maurice Fargues, who had resurrected us from the death cave at Vaucluse. We will not be consoled that we were unable to save him."
Besides the signed 120-meter marker on the line, Maurice left one more proof of his feat:

He etched his name into a rock slate at that depth, a fitting monument to this brave diver.

3. 253.2 meters (831 feet) is the deepest free dive made by Austrian Herbert Nitsch

Free diving can be done with various supporting equipment, but it must be done on a single breath - without use of the scuba equipment. There are numerous free-dive categories, such as with fins and without fins, length, static, and so on, with their individual records, but the most impressive by far is the so-called No-limits apnea (NLT), where any sort of equipment can be used to help diver descend and ascend. Naturally, this category is responsible for the deepest free-dive ever made.

This feat was accomplished by an Austrian free diver, Herbert Nitsch. Twice. He actually beat his own record he set in 2007, with his of 253.2 meters (831 feet) dive he made in 2012. In the no limit dives, motorized sleds have become the most popular means of descent and ascent, and Nitsch used a special, purpose built torpedo sled for his latest achievement. He had to train extensively for months, to prepare himself for a rapid shift in pressure that he was going to experience.

As one might notice, this depth is considerably greater than the scuba diving limit. This is because narcosis and oxygen toxicity only happen if we inhale gasses under pressure, not if we ourselves are subjected to it. However, Nitsch did suffer from several unpleasant effects: he suffered a blackout during the last 10 meters of his descent that he later described as "blackout through narcosis", which was found strange by some, as the expected culprit would be oxygen starvation. He regained his consciousness on the ascent, but suffered from serious symptoms of decompression and had to be helped by the safety divers in the last 10 meters of the ascent, which was followed by an emergency transfer to a decompression chamber that was on alert for this particular dive.
4. Deepest dive with scuba-gear stands at 332 meters (1,089 ft)

This amazing feat was done by the Egyptian diver Ahmed Gabr, who beat the previous world record of 318.25 meters (also made by Gabr in 2010). Gabr, who was 41 at the time, is an extremely accomplished diver with over 9000 dives to his belt. He was an officer in the Egyptian army, and is the only certified US combat diver in Egypt.

As already stated, the technical limit before oxygen toxicity kicks in is officially at 100 meters, but nothing stops expert divers to push further with special breathing gas mixtures. The Trimix (Oxygen-Nitrogen-Helium) mixture Gabr used is a jealously kept secret by Gabr and his team, along with his diving plan.

The initial plan for Gabr was to reach the round number of 350 meters, but he had to cut it short due to the high-pressure nervous syndrome (HPNS) he experienced during the last leg of his dive.

After he decided that it is too dangerous to continue he still had a long way to go:

His ascent took 13 hours and 35 minutes. He had to make frequent stops, in order to avoid decompression, each stop being longer as he approached the surface. While Gabr is the official record holder, a whole team of support divers, doctors, and other experts were part of this achievement.

All these extreme human dives pass the so-called euphotic zone which is the depth at which sun can penetrate water. The growing darkness of the ocean depths below 200 meters is one of the many causes for a myriad of bioluminescent creatures that inhabit the ocean, like various deep-sea fish, jellies, and plankton.

This change in light levels is also an important psychological factor for the divers, and lowered visibility increases this already dangerous endeavor.
5. Depth that deep diving sharks can reach is between 1,500 meters (5,000 feet) and 1800 meters (6000 feet)
The Frilled shark is a very unusual looking eel-like fish that spends most of its time at depths of 50-200 m (160-660 ft), but it has been caught as deep as 1,570 m (5,150 ft). This living fossil, dubbed so because of how old the species is, can reach up to 2 m (6.6 ft) in length.

Another deep diver is the so-called Bluntnose sixgill shark, with a slightly more conventional look. These sharks, commonly referred to as cow sharks, can reach lengths of 4.9 m (16 ft), and mostly feed on mollusks, crustaceans, and hagfish. Most sharks today have 5 gill slits, unlike the aptly named six gills shark, which makes this species older than most sharks, but still younger than the Frilled shark. These deep diving sharks can typically be found at depths greater than 90 m (300 ft), but in some cases sixgills have been recorded as deep as 6,000 feet (over 1,800 meters). These sharks tend to drift up while they're sleeping, so they can be found at shallow waters at times, but extremely rarely.
6. Deepest recorded whale dive is at 2,992 meters (9,816 feet)

What humans train for extensively for years, some mammals can do naturally. Of course, diving does come a bit easier to an animal that has evolved to live in the water. Whales can in general hold breath for hours and some species, like sperm whales, are notorious deep divers.

The deep diving crown goes to Cuvier's beaked whales:

This elusive species regularly dives to depths of more than 2000 meters (6600 ft), and one particular specimen is current record holder for both the longest and the deepest dive made by a whale.

This adventurous whale was recorded off the coast of California, where it was underwater for 2 hours and 17 minutes, with the maximum dive depth of whopping 2,992 meters (9,816 feet)!

The Cuvier's beaked whales, sperm whales, and other deep diving whales make these crazy dives in search of food. Whales are often found to have weird behavior, but this deep diving habit is fairly easily explained - their diet mostly consists of giant and colossal squids, and other deep diving whale-snacks. Besides high pressures, and other dangers of deep diving, such eating habits can be quite dangerous - a fact proven by numerous scars made by squid beaks commonly found on sperm whales.
7. Deepest part of the ocean, which we reached twice: 10,994 meters (36,070 feet)
There have been over 536 people, 30 monkeys, 12 dogs, cats, guinea pigs, rabbits, spiders in space so far but only 3 people have been to the deepest part of the ocean.

The deepest part of the ocean is the Challenger deep in Mariana Trench, located near the Mariana Islands in Pacific Ocean. It was first discovered by the British Royal Navy survey ship HMS Challenger, sometime in the 1870s. While it was a point of great fascination, we were able to send humans down there for the first time in the 1960, in special purpose-built bathyscape (A small submersible that is self propelled) called Trieste. Two men, scientist Jacques Piccard (son of the bathyscaphe designer August Piccard), and the US navy officer Don Walsh were selected for this particular mission.

Their decent took almost 5 hours, and allowed them to stay only 20 minutes on the ocean floor. Nevertheless, the information they brought back with them to surface was invaluable to the scientists of the time.

Our second time around went a bit better:

James Cameron, a Canadian director, dove in his Deep Submergence Vehicle (DSV), Deep Sea Challenger on March 26, 2012. Advances in technology could easily be seen, as his descend was almost two times faster than on the previous dive made by Trieste. Cameron spent around 3 hours on the ocean floor, before having to resurface. He donated the Deep Sea Challenger to the Woods Hole Oceanographic Institution, but the submarine never got in one piece there. It was damaged during the transport, when the track that carried it caught fire. Since then, it has been stored away in the Woods-Hole, but to this day hasn't been used again.

More than 536 people have been in space but only 3 have been to the deepest part of the ocean. Click to Tweet

Conclusion:

Ocean depths are amazing, mysterious, and intimidating. We know so little about them, yet they are literally at our doorstep.

We have explored a larger surface area of Moon and Mars, than of the ocean floor, but luckily we are making strides in understand our own planet more.

Ever since we started conquering our seas and oceans, they have been a symbol of human thirst for exploration, and our indomitable spirit.

One can only wonder, what wondrous discoveries await us down there.

Who knows what awaits us down there?

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How Deep Is The Ocean: An Incredible Facts About The Ocean's Depths

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There is a ton of information regarding how deep is the ocean, or how big it is. But one question that people often forget to ask is, where do we figure in there? How deep can we dive? How much of the ocean have we explored?

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Eris was first found by a team of astronomers at Palomar Observatory in California. Mike Brown and his team found Eris in 2003. It was not until 2005 that Eris was identified as another possible planet in our solar system. In 2006, astronomers decided that Eris should not be called a planet.

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One of the most important discoveries in medicine, the discovery of blood circulation is credited to the English physician William Harvey who, in 1628, was the first person to completely describe the systemic circulation and properties of blood being pumped to the brain and body by the heart.

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Over the course of ages, we have made countless discoveries that have improved the quality of our life and helped us to understand the world around us. It is very difficult (if not impossible) to rank the importance of the discoveries we have made, but one thing is for sure - some of them have literally changed our life. From penicillin and the screw pump to X-rays and electricity, here are 25 Biggest Scientific Discoveries in History of Mankind.

Feature Image: shutterstock

On March 26, 1953, American medical researcher Jonas Salk announced that he had successfully tested a vaccine against poliomyelitis, the virus that causes the crippling disease of polio. In 1952, an epidemic year for polio, there were 58,000 new cases reported in the US and more than 3,000 deaths caused by the disease.

Enjoy this post? Check out 25 Most Fascinating Scientific Discoveries Of 2015.

Lists Going Viral Right Now

Photos: 23. WP, Planets2013, CC BY-SA 3.0, 22. Bryan Brandenburg, 21. David Hawgood via geographic.org.uk, 17. Ildar Sagdejev ( Specious), 2008-07-11 Air conditioners at UNC-CH, CC BY-SA 4.0, 12. © Nevit Dilmen, Medical X-Ray imaging FKJ04 nevit, CC BY-SA 3.0, 10. Sandbh, 18 column periodic table, with Lu and Lr in group 3, CC BY-SA 4.0, 9. AIRS via flickr, CC BY 2.0, 8. Mj-bird, HITACHI, Magnetic Resonance Imaging System, ECHELON OVAL,, CC BY-SA 3.0, 2. William Hook via flickr, CC BY-SA 2.0, 1. GDC Global via flickr, CC BY 2.0

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25 Biggest Scientific Discoveries In History Of Mankind

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From penicillin and the screw pump to X-rays and electricity, here are 25 Biggest Scientific Discoveries in History of Mankind.

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The line for iPads at Apple's flagship Manhattan store on the first day the product was released, Saturday April 3.

Credit: Denise Chow

When Apple released its iPad, people lined up for hours to get their hands on the latest shiny techno-gadget stamped with the Apple logo.

While there likely wasn't reason to worry iPads would go out of style, or worse, become unavailable, and those die-hard consumers didn't urgently need the tablet for an essential task that same day, still the lines persisted - as they often do when Apple comes out with something new.

The seemingly odd behavior makes sense to market researchers and psychologists who weigh in on the reasons for Apple's cult-like following, and why members feel such affection for these products.

The unadulterated loyalty often invovles brand-centric fan groups, which scientists refer to as brand communities. These groups, which have formed around Apple, Harley-Davidson and even Hello Kitty, seem to rise up largely without the aid of sly marketing campaigns and instead by grassroots movements with their own rituals and traditions. Some even say the Apple community has the makings of a cult, with fanaticism that comes close to religious furor.

These groups can form out of necessity, the desire to be part of a community, and a shared sense that members understand something that, well, not everybody else gets.

In addition, Apple fans always have something new to keep their interest, an important component in fueling any fanaticism, researchers say. And, as is the case with fans of any brand, objects can become more than the sum of their parts - they can represent a lifestyle and more.

"I think people have values that they're pursuing, they have core goals in their life, and it's different for different people, but Apple has done a good job of becoming symbolically part of one type of lifestyle, or one type of concept," said Lynn Kahle, a professor of marketing at the University of Oregon who studies consumer psychology. "The brand becomes more than just a set of attributes to get you somewhere, it's a core part of who you are."

I'm a Mac...

A key component of any brand community is what researchers call "consciousness of kind," which really means a sense of "we-ness." Today, this element is driven home in the Mac community by the "I'm a PC, I'm a Mac" ad campaign that the company started running in 2006. But the bond between Mac users stretches back decades.

"I remember speaking to early Mac fans, folks who had adopted the platform back in the 80s, and they would tell me things like: 'At that time, it was clear, IBM people were one way - wore suits and voted for Reagan. Mac people were another way - wore jeans and didn't vote for Reagan,'" said Albert M. Muniz, Jr., a professor of marketing at DePaul University in Chicago, who has studied the Apple brand community.

Brand communities also involve rituals and traditions, or some type of shared culture. Harley riders have their group rides; Apple users have store openings or a new product release. As was evident with the iPad, loyalists chose to camp out despite the fact that, if they simply wanted the product, they could have ordered it online.

Finally, members feel an obligation to each other, and help each other out - like a Harley rider who stops on the side of the road to help another Harley rider, Muniz said.

"There's probably a belief that 'This person is like me, at some level they get it,'" Muniz said. With Apple users, "there might be an assumption that there are shared values on a whole range of things, but certainly on computing," he said.

Why do these groups form?

Strong brand followings don't tend to form at the snap of a marketer's fingers. In fact, it's the other way around.

"To date, the strongest examples of brand community I've encountered have been grass roots in nature, meaning, they have formed independent of the marketer," Muniz said.

In other words, there's often no telling what brand will strike a chord with people - these groups tend to have a life of their own. For example, some other companies that have tried to rally a cult following, like Saturn cars, were not as successful, said Russell Belk, a marketing professor at York University in Ontario, Canada.

One reason groups like the Apple community form is purely out of necessity. Macs have always been a minority computer compared with PCs, and if users have a problem with their device, they often find themselves turning to other community members for help, making the bonds between users all the more strong.

Then, there's the feeling that you're part of something special, which ties into the sense of "we-ness." For Apple users, there might be the feeling that, by going with the PC-alternative, they're heading against the mainstream. It's the idea that "We're the people marching to a different drum, if there are fewer of us, that just proves that we understand something that not everyone else can get," Muniz said.

Scott Thorne, a marketing professor at Southeast Missouri State University, has also seen this type of exclusiveness in many fan communities, some of which use jargon as a way to refer to outsiders. "It's kind of a way to feel superior - 'We know something you don't, we're aware how cool this product is, or how good this singer is, or how cool this technology is, we know something that other people are not aware of,'" Thorne said.

Brand communities might also serve as a substitute for real, location-based communities, which recent research suggests are declining.

"There's less community, and we're social creatures, so I've always suspected that we seek or create or reinforce community where we find it," Muniz said. "So if we can create community around a shared interest or brand, that can become a platform for generating that kind of social contact, generating that kind of cohesion or collectivity."

Fan, fanatic

Within these communities, all members seem to have shared characteristics that denote them as fans.

Thorne and his colleagues have identified four: They have a personal interested in the topic or product; they do things to show that they're fans (like wearing a T-shirt); they feel the need to associate with others that share their interests; and they feel the need to find out more about the object of their fanaticism.

Such fanaticism, defined as excessive devotion or enthusiasm, can have components of addiction or obsession. But research has also shown it doesn't usually cause harm to the consumer or to others.

Not all fanatics are created equal, and Thorne has found there are generally four flavors of fandom:

Dilettante - Casual involvement. To take a baseball example, if the game is on, you'll watch it, but won't go out of your way to do so.

Dedicated - If the game is on, you make a point to be home, and you might make your own fantasy baseball league.

Devoted - You might fly out to see your favorite team play around the county, and have a shrine of memorabilia in your home.

Dysfunctional - A level that's disruptive to the individual or society. (Think planning one's wedding around baseball season.)

"At all three of [the first] levels, your family and society may view you as eccentric, but you're not viewed as harmful or dangerous," Thorne said.

Generally, if there's nothing new to continue one's interest in a "brand," most fans will go back to the casual level.

However, Apple fans never want for such stimulation.

"That's one of the reasons Apple has such a devoted fandom, is because there's always talk about what's the next product Apple's going to come out with," Thorne said.

Is Apple a cult?

Some market researchers have gone so far as to dub Apple fans a "brand cult," a group with some cult-like attributes.

Here's why: Some fans have retold and romanticized Apple's history, giving a "legend" quality to the company and its founders. In 2005, Belk and his colleges found evidence for several myths within the Apple community, including a "creation myth" involving the creation of one of the first computers in Apple founder and CEO Steve Jobs's garage, a"heroic myth" surrounding the founders, and a "satanic component" involving the company's rivals, portraying them almost like the Antichrist.

"I think that if ever there is a brand cult, Apple deserves it, they come close to religious fanaticism on the part of enthusiastic followers," Belk said.

He points to some Apple enthusiasts who went out and bought iPads despite complaining early on that the iPad didn't offer much new, saying it was essentially a big iPod touch.

"That sort of loyalty and devotion would suggest that there's something more than an objective appraisal going on, and it's the same sort of faith and loyalty that we see in religions oftentimes," he said.

However, some feel "cult" is too strong a label to throw around when discussing brand communities, since it conjures thoughts of conflict surrounding other cult groups, such as religious cults. "That's kind of heavy baggage, it's an emotionally charged word," Muniz said.

It's a lifestyle

Whether or not Apple fans are cult-like, there is no doubt that a strong sense of devotion to the brand is there. At the core of the devotion could be "a sense of self." The brand taps into what's truly important to people - it's about more than just the technological bells and whistles, it's a lifestyle, experts say.

"Apple I think has done a good job of having its brandimage connect to the core values and core lifestyle aspects of people," said Kahle, of the University of Oregon.

He points to the famous "1984" Macintosh Super Bowl ad, which alluded to George Orwell's book by the same name. In the ad, people were mindlessly watching a screen, meant to symbolize Big Brother, or conformity. A woman comes in and throws a hammer at the screen, blowing it up.

"The implication is, if you don't want a world like '1984,' you should identify with Apple," Kahle said. "Apple created an image as being a brand that's associated with independence and freedom, that the kind of tyranny of technology that's too complicated for people to use, that's something Apple was against. And Apple would create freedom or independence for you through technology, as opposed to making you a slave to technology."

Apple fans are also expressing a certain mindset.

"I would really consider people who use it [as] open-minded to technology, and liberal and everything," said Florian Brunbauer, an Apple user who designs and sells iPhone and iPad apps, and who stood in line the day the iPad was released. "I think it's a way to express that too."

Appealing product

All that said, Apple fans aren't just crazed over nothing. The company has at times been a technology innovator, said, Kahle, popularizing new concepts, like the idea of a computer mouse. And products often come with a sleek, different design that users find appealing.

Also, many of the products integrate with each other - you download iTunes on your iMac to put music on your iPod, for instance.

"That's the only way to guarantee the best experience I think," Brunbauer said. "Everything you're using comes from the same company, and that really helps. The whole process all works together, and it's very efficient in a way that you cannot achieve at all with Windows."

And since Apple allows third party developers to design applications for its products, such as the iPhone, users with a little programming know-how can jump right in and broaden the product's toolkit beyond what's provided by the company.

And fans find the products to be user-friendly, a plus with any kind of technology.

"You don't really have to learn how to use a Mac," Brunbauer said. "You just start it, and it all makes sense."

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Apple Obsession: The Science of iPad Fanaticism

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When Apple released its iPad, people lined up for hours to get their hands on the latest shiny techno-gadget stamped with the Apple logo. While there likely wasn't reason to worry iPads would go out of style, or worse, become unavailable, and those die-hard consumers didn't urgently need the tablet for an essential task that same day, still the lines persisted - as they often do when Apple comes out with something new.

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The oldest flying squirrel fossil ever found has unearthed new insight on the origin and evolution of these airborne animals.

Writing in the open-access journal eLife, researchers from the Institut Català de Paleontologia Miquel Crusafont (ICP) in Barcelona, Spain, described the 11.6-million-year-old fossil, which was discovered in Can Mata landfill, approximately 40 kilometers outside the city.

"Due to the large size of the tail and thigh bones, we initially thought the remains belonged to a primate," says first author Isaac Casanovas-Vilar, researcher at the ICP. In fact, and much to the disappointment of paleoprimatologists, further excavation revealed that it was a large rodent skeleton with minuscule specialised wrist bones, identifying it as Miopetaurista neogrivensis -- an extinct flying squirrel.

Combining molecular and paleontological data to carry out evolutionary analyses of the fossil, Casanovas-Vilar and the team demonstrated that flying squirrels evolved from tree squirrels as far back as 31 to 25 million years ago, and possibly even earlier.

In addition, their results showed that Miopetaurista is closely related to an existing group of giant flying squirrels called Petaurista. Their skeletons are in fact so similar that the large species that currently inhabits the tropical and subtropical forests of Asia could be considered living fossils.

With 52 species scattered across the northern hemisphere, flying squirrels are the most successful group of mammals that adopted the ability to glide. To drift between trees in distances of up to 150 metres, these small animals pack their own 'parachute': a membrane draping between their lower limbs and the long cartilage rods that extend from their wrists. Their tiny, specialised wrist bones, which are unique to flying squirrels, help support the cartilaginous extensions.

But the origin of these animals is highly debated. While most genetic studies point towards the group splitting from tree squirrels about 23 million years ago, some 36-million-year-old remains that could belong to flying squirrels have previously been found. "The problem is that these ancient remains are mainly teeth," Casanovas-Vilar explains. "As the dental features used to distinguish between gliding and non-gliding squirrels may actually be shared by the two groups, it is difficult to attribute the ancient teeth undoubtedly to a flying squirrel. In our study, we estimate that the split took place around 31 and 25 million years ago, earlier than previously thought, suggesting the oldest fossils may not belong to flying squirrels.

"Molecular and paleontological data are often at odds, but this fossil shows that they can be reconciled and combined to retrace history," he adds. "Discovering even older fossils could help to retrace how flying squirrels diverged from the rest of their evolutionary tree."
An exceptional site in a rubbish dump
The Can Mata landfill holds a set of more than 200 sites ranging in age between 12.6 and 11.4 Ma (middle to late Miocene). In the last 20 years, excavations carried out by the ICP in Can Mata have led to the identification of more than 80 species of mammals, birds, amphibians and reptiles. A remarkable number of primate remains from the site have revealed three new species of hominoids, nicknamed 'Pau' (Pierolapithecus catalaunicus), 'Laia' (Pliobates cataloniae) and 'Lluc' (Anoiapithecus brevirostris). Various studies of mammal remains recovered from the site, including the current work in eLife, indicate the existence of a dense subtropical forest.

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new species; trees; evolutionary biology; nature; fossils; evolution; early mammals; origin of life

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Oldest fossil of a flying squirrel sheds new light on its evolutionary tree

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The oldest flying squirrel fossil ever found has unearthed new insight on the origin and evolution of these airborne animals. Writing in the open-access journal eLife, researchers from the Institut Català de Paleontologia Miquel Crusafont (ICP) in Barcelona, Spain, described the 11.6-million-year-old fossil, which was discovered in Can Mata landfill, approximately 40 kilometers outside the city.

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A new species of a giant dinosaur has been found in South Africa's Free State Province. The plant-eating dinosaur, named , weighed 12 tonnes and stood about four metres high at the hips. Ledumahadi mafube was the largest land animal alive on Earth when it lived, nearly 200 million years ago. It was roughly double the size of a large African elephant.

A team of international scientists, led by University of the Witwatersrand (Wits) palaeontologist Professor Jonah Choiniere, described the new species in the journal Current Biology today.

The dinosaur's name is Sesotho for "a giant thunderclap at dawn" (Sesotho is one of South Africa's 11 official languages and an indigenous language in the area where the dinosaur was found).

"The name reflects the great size of the animal as well as the fact that its lineage appeared at the origins of sauropod dinosaurs," said Choiniere. "It honours both the recent and ancient heritage of southern Africa."

Ledumahadi mafube is one of the closest relatives of sauropod dinosaurs. Sauropods, weighing up to 60 tonnes, include well-known species like Brontosaurus. All sauropods ate plants and stood on four legs, with a posture like modern elephants. Ledumahadi evolved its giant size independently from sauropods, and although it stood on four legs, its forelimbs would have been more crouched. This caused the scientific team to consider Ledumahadi an evolutionary "experiment" with giant body size.

Ledumahadi's fossil tells a fascinating story not only of its individual life history, but also the geographic history of where it lived, and of the evolutionary history of sauropod dinosaurs.

"The first thing that struck me about this animal is the incredible robustness of the limb bones," says lead author, Dr Blair McPhee. "It was of similar size to the gigantic sauropod dinosaurs, but whereas the arms and legs of those animals are typically quite slender, Ledumahadi's are incredibly thick. To me this indicated that the path towards gigantism in sauropodomorphs was far from straightforward, and that the way that these animals solved the usual problems of life, such as eating and moving, was much more dynamic within the group than previously thought."

The research team developed a new method, using measurements from the "arms" and "legs" to show that Ledumahadi walked on all fours, like the later sauropod dinosaurs, but unlike many other members of its own group alive at its time such as Massospondylus. The team also showed that many earlier relatives of sauropods stood on all fours, that this body posture evolved more than once, and that it appeared earlier than scientists previously thought.

"Many giant dinosaurs walked on four legs but had ancestors that walked on two legs. Scientists want to know about this evolutionary change, but amazingly, no-one came up with a simple method to tell how each dinosaur walked, until now," says Dr Roger Benson.

By analysing the fossil's bone tissue through osteohistological analysis, Dr Jennifer Botha-Brink from the South African National Museum in Bloemfontein established the animal's age.

"We can tell by looking at the fossilised bone microstructure that the animal grew rapidly to adulthood. Closely-spaced, annually deposited growth rings at the periphery show that the growth rate had decreased substantially by the time it died," says Botha-Brink. This indicates that the animal had reached adulthood.

"It was also interesting to see that the bone tissues display aspects of both basal sauropodomorphs and the more derived sauropods, showing that Ledumahadi represents a transitional stage between these two major groups of dinosaurs."

Ledumahadi lived in the area around Clarens in South Africa's Free State Province. This is currently a scenic mountainous area, but looked much different at that time, with a flat, semi-arid landscape and shallow, intermittently dry streambeds.

"We can tell from the properties of the sedimentary rock layers in which the bone fossils are preserved that 200 million years ago most of South Africa looked a lot more like the current region around Musina in the Limpopo Province of South Africa, or South Africa's central Karoo," says Dr Emese Bordy.

Ledumahadi is closely related to other gigantic dinosaurs from Argentina that lived at a similar time, which reinforces that the supercontinent of Pangaea was still assembled in the Early Jurassic. "It shows how easily dinosaurs could have walked from Johannesburg to Buenos Aires at that time," says Choiniere.

South Africa's Minister of Science and Technology Mmamoloko Kubayi-Ngubane says the discovery of this dinosaur underscores just how important South African palaeontology is to the world.

"Not only does our country hold the Cradle of Humankind, but we also have fossils that help us understand the rise of the gigantic dinosaurs. This is another example of South Africa taking the high road and making scientific breakthroughs of international significance on the basis of its geographic advantage, as it does in astronomy, marine and polar research, indigenous knowledge, and biodiversity," says Kubayi-Ngubane.

The research team behind Ledumahadi includes South African-based palaeoscientists, Dr Emese Bordy and Dr Jennifer Botha-Brink, from the University of Cape Town and the South African National Museum in Bloemfontein, respectively.

The project also had a strong international component with the collaboration of Professor Roger BJ Benson of Oxford University and Dr Blair McPhee, currently residing in Brazil.

"South Africa employs some of the world's top palaeontologists and it was a privilege to be able to build a working group with them and leading researchers in the UK," says Choiniere, who recently emigrated from the USA to South Africa. "Dinosaurs didn't observe international boundaries and it's important that our research groups don't either."

Video: https://www.youtube.com/watch?v=Q8FHxPocwDM

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extinction; animals; nature; new species; dinosaurs; paleontology; fossils; ancient dna

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Ledumahadi mafube: South Africa's new jurassic giant

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A new species of a giant dinosaur has been found in South Africa's Free State Province. The plant-eating dinosaur, named Ledumahadi mafube, weighed 12 tons and stood about four meters high at the hips. Ledumahadi mafube was the largest land animal alive on Earth when it lived, nearly 200 million years ago.

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Air Conditioning

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Many Americans are turning to their air conditioners to combat the current heat wave. These artificial breezes are a relatively novel innovation, however, as this history of air conditioning explains. Throughout the ages, humans have gone to great lengths to keep cool, from transporting mountains of snow to putting their underwear in the icebox, as Will Oremus reported in 2011. His original article is reprinted below.

Anyone tempted to yearn for a simpler time must reckon with a few undeniable unpleasantries of life before modern technology: abscessed teeth, chamber pots, the bubonic plague-and a lack of air conditioning in late July. As temperatures rise into the triple digits across the eastern United States, it's worth remembering how we arrived at the climate-controlled summer environments we have today.

Until the 20 th century, Americans dealt with the hot weather as many still do around the world: They sweated and fanned themselves. Primitive air-conditioning systems have existed since ancient times, but in most cases, these were so costly and inefficient as to preclude their use by any but the wealthiest people. In the United States, things began to change in the early 1900s, when the first electric fans appeared in homes. But cooling units have only spread beyond American borders in the last couple of decades, with the confluence of a rising global middle class and breakthroughs in energy-efficient technology.

Attempts to control indoor temperatures began in ancient Rome, where wealthy citizens took advantage of the remarkable aqueduct system to circulate cool water through the walls of their homes. The emperor Elagabalus took things a step further in the third century, building a mountain of snow-imported from the mountains via donkey trains-in the garden next to his villa to keep cool during the summer. Marvelously inefficient, the effort presaged the spare-no-cost attitude behind our modern-day central air-conditioning systems. Even back then some scoffed at the concept of fighting heat with newfangled technologies. Seneca, the stoic philosopher, mocked the "skinny youths" who ate snow to keep cool rather than simply bearing the heat like a real Roman ought to.

Such luxuries disappeared during the Dark Ages, and large-scale air-conditioning efforts didn't resurface in the West until the 1800s, when well-funded American engineers began to tackle the problem. In the intervening centuries, fans were the coolant of choice. Hand fans were used in China as early as 3,000 years ago, and a second-century Chinese inventor has been credited with building the first room-sized rotary fan (it was powered by hand). Architecture also played a major role in pre-modern temperature control. In traditional Middle Eastern construction, windows faced away from the sun, and larger buildings featured " wind towers" designed to catch and circulate the prevailing breezes.

In late 19 th-century America, engineers had the money and the ambition to pick up where the Romans had left off. In 1881, a dying President James Garfield got a respite from Washington, D.C.'s oppressive summer swelter thanks to an awkward device involving air blown through cotton sheets doused in ice water. Like Elagabalus before him, Garfield's comfort required enormous energy consumption; his caretakers reportedly went through half a million pounds of ice in two months.

The big breakthrough, of course, was electricity. Nikola Tesla's development of alternating current motors made possible the invention of oscillating fans in the early 20 th century. And in 1902, a 25-year-old engineer from New York named Willis Carrier invented the first modern air-conditioning system. The mechanical unit, which sent air through water-cooled coils, was not aimed at human comfort, however; it was designed to control humidity in the printing plant where he worked. In 1922, he followed up with the invention of the centrifugal chiller, which added a central compressor to reduce the unit's size. It was introduced to the public on Memorial Day weekend, 1925, when it debuted at the Rivoli Theater in Times Square. For years afterward, people piled into air-conditioned movie theaters on hot summer days, giving rise to the summer blockbuster.

It's not an exaggeration to say that Carrier's innovation shaped 20 th-century America. In the 1930s, air conditioning spread to department stores, rail cars, and offices, sending workers' summer productivity soaring. Until then, central courtyards and wide-open windows had offered the only relief. Residential air conditioning was slower to take hold: As late as 1965, just 10 percent of U.S. homes had it, according to the Carrier Corporation. Families in the South made do by sleeping on the porch or even putting their underwear in the icebox. By 2007, however, the number was 86 percent. As cool air spread across the country, Sun Belt cities that had been unbearable in the summer became more attractive places to live and work, facilitating a long-term shift in U.S. population.

Europeans have been slower to embrace air conditioning, but like cold beer and ice water, it's beginning to catch on there, too. Data on air conditioning in the developing world is scarce, but it's safe to say most Africans and South Asians still make do without it. A recent Times of India article on how to stay cool in summer recommended wearing linens and drinking lots of fluids to avoid heat stroke. The modern Indian version of iced tea on the front porch? Nimbu paani from a street cart.

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Many Americans are turning to their air conditioners to combat the current heat wave. These artificial breezes are a relatively novel innovation, however, as this history of air conditioning explains. Throughout the ages, humans have gone to great lengths to keep cool, from transporting mountains of snow to putting their underwear in the icebox, as Will Oremus reported in 2011.

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The amount of plastic washing up onto the shores of remote South Atlantic islands is 10 times greater than it was a decade ago, according to new research published today (8 October) in the journal Current Biology.

Scientists investigating plastics in seas surrounding the remote British Overseas Territories discovered they are invading these unique biologically-rich regions. This includes areas that are established or proposed Marine Protected Areas (MPAs).

The study shows for the first time that plastic pollution on some remote South Atlantic beaches is approaching levels seen in industrialised North Atlantic coasts.

During four research cruises on the BAS research ship RRS James Clark Ross between 2013 and 2018, a team of researchers from ten organisations sampled the water surface, water column and seabed, surveyed beaches and examined over 2000 animals across 26 different species.

The amount of plastic reaching these remote regions has increased at all levels, from the shore to the seafloor. More than 90% of beached debris was plastic, and the volume of this debris is the highest recorded in the last decade.

Lead author Dr David Barnes from British Antarctic Survey (BAS) explains:

"Three decades ago these islands, which are some of the most remote on the planet, were near-pristine. Plastic waste has increased a hundred-fold in that time, it is now so common it reaches the seabed. We found it in plankton, throughout the food chain and up to top predators such as seabirds."

The largest concentration of plastic was found on the beaches. In 2018 we recorded up to 300 items per metre of shoreline on the East Falkland and St Helena -- this is ten times higher than recorded a decade ago. Understanding the scale of the problem is the first step towards helping business, industry and society tackle this global environmental issue."

Plastic causes many problems including entanglement, poisoning and starving through ingestion. The arrival of non-indigenous species on floating plastic "rafts" has also been identified as a problem for these remote islands. This study highlights that the impacts of plastic pollution are not only affecting industrialised regions but also remote biodiverse areas, which are established or proposed MPAs.

Andy Schofield, biologist, from the RSPB, who was involved in this research says:

"These islands and the ocean around them are sentinels of our planet's health. It is heart-breaking watching Albatrosses trying to eat plastic thousands of miles from anywhere. This is a very big wake up call. Inaction threatens not just endangered birds and whale sharks, but the ecosystems many islanders rely on for food supply and health."

Journal Reference:

D.K.A. Barnes, S.A. Morley, J. Bell, P. Brewin, K. Brigden, M. Collins, T. Glass, W.P. Goodall-Copestake, L. Henry, V. Laptikhovsky, N. Piechaud, A. Richardson, P. Rose, C.J. Sands, A. Schofield, R. Shreeve, A. Small, T. Stamford, B. Taylor. Marine plastics threaten giant Atlantic Marine Protected Areas. Current Biology, 2018; 28 (19): R1137 DOI: 10.1016/j.cub.2018.08.064

Cite This Page:

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new species; nature; marine biology; soil types; recycling and waste; geography; environmental issues; environmental awareness

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Increase in plastics waste reaching remote South Atlantic islands

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The amount of plastic washing up onto the shores of remote South Atlantic islands is 10 times greater than it was a decade ago, according to new research. Scientists investigating plastics in seas surrounding the remote British Overseas Territories discovered they are invading these unique biologically-rich regions.

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A new study shows that Atlantic salmon use the Earth's magnetic field as a navigational tool -- much like their cousins, Pacific salmon -- and don't lose that ability through several generations of fish even after they have been transplanted into a land-locked lake.

The findings suggest that Atlantic salmon, which are widely used in aquaculture, may have greater potential to navigate and thus invade novel habitats if they escape their pens, researchers say.

Results of the study are being published this week in the journal Proceedings of the National Academy of Sciences.

This is the first time in which scientists have documented that another genus of salmon use the magnetic field as a map for navigation. A landmark 2014 study by Oregon State University researchers show that Chinook salmon use the magnetic field to orient themselves as they migrate over hundreds, even thousands of miles through the Pacific Ocean to target their oceanic foraging grounds.

The researchers constructed a testing apparatus at the Oregon Hatchery Research Center with several "arenas" surrounded by wooden coils wrapped in copper wire to mimic Earth's magnetic field, and tested 1,150 juvenile Atlantic salmon transported from Oregon's Hosmer Lake.

Atlantic salmon had first been brought to the land-locked lake from Maine some 60 years ago, and the researchers were curious to see if they had navigational abilities similar to ocean-going salmon, according to lead author Michelle Scanlan, faculty research assistant in OSU's College of Agricultural Sciences and lead author on the PNAS article.

"We wanted to see how Atlantic salmon would respond if we put them into different magnetic fields at the boundaries of Pacific salmon oceanic range," Scanlan said. "If we put them into an extreme northern field, would they 'course-correct' and align themselves in a southerly direction, and vice-versa? And the answer was yes. They clearly aligned themselves in the tank to adjust to an appropriate magnetic field signal."

This ability to use the magnetic field to navigate by land-locked Atlantic salmon is of particular concern because of an incident in August of 2017, when 200,000 to 300,000 Atlantic salmon escaped an aquaculture pen in Washington's Puget Sound. Eight months later, one of the fish was reportedly caught 40 miles up the Skagit River, raising concerns about the impact on native salmon and the ecosystem.

The state of Washington has since banned Atlantic salmon farms.

The study also raises some interesting questions about how long fish in general, and salmon in particular, retain skills they no longer need, said Nathan Putman, a senior scientist with LGL Ecological Research Associates in Bryan, Texas, who led the 2014 Pacific salmon navigation study as a post-doctoral scholar at OSU.

"Why didn't the Hosmer Lake fish lose their ability to navigate?" Putman said. "It apparently isn't a 'use it or lose it' skill. It may be possible that they have some finer-scale navigation tools at their disposal to use in a lake. Even at small-scales, fish are confronted by a variety of spatial tasks that might benefit from use of magnetic cues -- from traveling in a straight line to maneuvering through the water column. More research is needed to answer those questions."

A study by the same researchers published in February in Biology Letters found that larval salmon use the magnetic field when emerging from "redds" or nests and into the water column -- suggesting salmon do have some fine-scale magnetic tools that may not have been fully identified.

On a broad scale, however, the use of the magnetic field explains, in part, how salmon can find the way to their river of origin.

"The magnetic field is kind of like having a GPS system in your car," said Amanda Pollock, a graduate student in OSU's Department of Fisheries and Wildlife and co-author on the study. "That gets them close to their river and then their olfactory senses kick in."

And that ability is retained even throughout many generations of landlocked individuals.

The senior scientist for the project is David Noakes, professor in the OSU Department of Fisheries and Wildlife.

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fisheries; fish; marine biology; agriculture and food; atmosphere; geomagnetic storms; geography; water

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Land-locked Atlantic salmon also use magnetic field to navigate

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A new study shows that Atlantic salmon use the Earth's magnetic field as a navigational tool -- much like their cousins, Pacific salmon -- and don't lose that ability through several generations of fish even after they have been transplanted into a land-locked lake.

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This question does not have a straightforward answer. The history of the automobile is very rich and dates back to the 15th century when Leonardo da Vinci was creating designs and models for transport vehicles.

There are many different types of automobiles - steam, electric, and gasoline - as well as countless styles. Exactly who invented the automobile is a matter of opinion. If we had to give credit to one inventor, it would probably be Karl Benz from Germany. Many suggest that he created the first true automobile in 1885/1886.

Below is a table of some automobile firsts, compiled from information in Leonard Bruno's book Science and Technology Firsts (Detroit, c1997) and ThoughtCo.'s History of the Automobile.

Further Reading

Bruno, Leonard. Transportation. In Science and technology firsts. Detroit, Gale, c1997: 499-534.

Burness, Tad. Ultimate auto album: an illustrated history of the automobile. Iola, WI, Krause Publications, c2001. 503 p.

Coffey, Frank. America on wheels: the first 100 years: 1896-1996. Los Angeles, General Publishing Group, c1998. 304 p.

Eckermann, Erik. World history of the automobile. Warrendale, PA, Society of Automotive Engineers, c2001. 371 p.

Georgano, G.N., and Thorkil Ry Andersen, editors. The new encyclopedia of motorcars, 1885 to the present. New York, Dutton, 1982. 688 p.

Lafferty, Peter. Top gear: the history of automobiles. New York, F. Watts, c1990. 32 p.

For more print resources...
Search on "automobiles history" or "automobile industry and trade" in the Library of Congress Online Catalog.

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invent automobile car karl benz question everyday mystery mysteries science fact kids fun library congress science reference services

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This question does not have a straightforward answer. The history of the automobile is very rich and dates back to the 15th century when Leonardo da Vinci was creating designs and models for transport vehicles. There are many different types of automobiles - steam, electric, and gasoline - as well as countless styles.

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A supernova is the explosion of a star -- the largest explosion that takes place in space.

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A progressively drying climate punctuated by variable wetter episodes may have precipitated the transition from our hominin ancestors to anatomically modern humans, according to research published on Oct. 8 in the online edition of the Proceedings of the National Academy of Science (PNAS).

Since the discovery of a rich assemblage of human fossils as well as stone tools and other archeological evidence in the rift valley of East Africa, a region often referred to as the cradle of humanity, scientists have attempted to piece together the complex puzzle that is the history of our human origins, including the environmental context of that history.

The study, based on lake sediment cores, is the first to provide a continuous environmental context for the diverse archeological evidence recovered from nearby localities in the rift valley basins of southern Kenya. The cores were sampled from Lake Magadi as part of the Hominin Sites and Paleolakes Drilling Project, or HSPDP, which is directed by University of Arizona professor Andrew Cohen.

Lake Magadi, a shallow, periodically dry lake, is close to the Olorgesailie basin in Kenya, one of the most productive sites for archaeological evidence of human evolution in Africa. The authors suggest that the profound climatic changes may have been driving forces behind hominin evolution, the origins of modern Homo sapiens and the onset of the Middle Stone Age.

While previous hypotheses have related hominin evolution to climate change, most prior studies lack regional-scale evidence for a link between environment and hominin evolution, the authors write in the paper, "Progressive aridification in East Africa over the last half million years and implications for human evolution." According to the study, a trend toward intense aridification in the area began 575,000 years ago. The change, not previously documented in continuous continental cores from East Africa, corresponds with faunal extinctions and a major transformation in stone tool technology documented in the Olorgesailie region.

"Much evidence for human evolution has been gathered from the area, but linking those records to detailed environmental records was missing until now," said the study's lead author, Richard Owen, of Hong Kong Baptist University. "There is a big gap in the records between the last Early Stone Age tools 500,000 years ago and the appearance of Middle Stone Age tools about 320,000 years ago. Our results plugged that gap with a continuous environmental record."

A critical transition occurred sometime during this gap, a period for which archeologists have unearthed evidence of a leap in early humans' abilities to make, use and trade stone tools.

The cores from Lake Magadi provide the first detailed link between climate change and events known from the region's archeological record.

"We have known for a while that the climate at the time was very varied, but the key here is that the records are in proximity to the archeological evidence for this transition," says Cohen, a professor in the University of Arizona's Department of Geosciences. "The older stone tools found at Olorgesailie did not change much between 1.2 million and a half-million years ago. And suddenly, after 500,000 and before 320,000 years ago -- we don't know exactly when, but in that timespan -- there was a critical transition in archeology when tools became more sophisticated and were transported over longer distances."

At the same time the lake core records point to the climate becoming drier and more variable, there is evidence elsewhere in Africa of the appearance of modern Homo sapiens, prompting much speculation whether the two are connected, Cohen said.

"Whether the evolution of bigger brains goes hand in hand with new toolkits is not entirely clear," he said. "But the earliest modern Homo sapiens fossils from Morocco date back 325,000 years, the same time we see this transition of tools. And both happened around the same time that our core record indicates severe drying very close to the archeological sites."

The deepest core drilled at Lake Magadi reached 200 meters (650 feet), penetrating all sedimentary layers down to the volcanic bedrock of the lake. The core samples, each about 10 feet long and 2 1/2 inches in diameter, are cut into manageable 5-foot segments, packaged and air-freighted to the National Lake Core Facility at the University of Minnesota for curation, analysis and storage.

According to the hypothesis of variability selection, a rapidly changing environment creates selective pressure that forces species to adapt to rapid change, Owen said. Under that scenario, the larger brains of anatomically modern humans would have allowed our ancestors to adapt quickly to an increasingly less predictable world.

"Now we have evidence that at the same time the toolkits were changing, the mammal fauna changed and the climate became more arid," Owen said. "So you have a series of coincidences that makes you think, 'This could be real.' Now we can say when the environment changed and then compare that to the archeological evidence of the region."

Drilling at other nearby sites by HSPDP has been completed as researchers gather more of the region's climate data to continue studying the importance of environmental variability in the course of human evolution.

The Hong Kong Research Grants Council, the International Continental Drilling Program, the U.S. National Science Foundation and the Ministry of Science and Technology of Taiwan funded the research.

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climate; environmental awareness; ice ages; environmental policy; early climate; human evolution; early humans; evolution

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Drier, less predictable environment may have spurred human evolution

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Evidence of a variable but progressively drying climate coincides with a major shift in stone-tool-making abilities and the appearance of modern Homo sapiens. Sediment cores obtained by the Hominin Sites and Paleolakes Drilling Project provide the first continuous environmental context for the diverse archeological evidence recovered from nearby localities in the East African rift valley.

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NASA Telescope Reveals Record-Breaking Exoplanet Discovery

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NASA's Spitzer Space Telescope has revealed the first known system of seven Earth-size planets around a single star. Three of these planets are firmly located in the habitable zone, the area around the parent star where a rocky planet is most likely to have liquid water.

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The Royal Swedish Academy of Sciences has decided to award the Sveriges Riksbank Prize in Economic Sciences in Memory of Alfred Nobel 2018 to William D. Nordhaus, Yale University, New Haven, USA "for integrating climate change into long-run macroeconomic analysis" and Paul M. Romer, NYU Stern School of Business, New York, USA "for integrating technological innovations into long-run macroeconomic analysis."
Integrating innovation and climate with economic growth
William D. Nordhaus and Paul M. Romer have designed methods for addressing some of our time's most basic and pressing questions about how we create long-term sustained and sustainable economic growth.

At its heart, economics deals with the management of scarce resources. Nature dictates the main constraints on economic growth and our knowledge determines how well we deal with these constraints. This year's Laureates William Nordhaus and Paul Romer have significantly broadened the scope of economic analysis by constructing models that explain how the market economy interacts with nature and knowledge.
Technological change
Romer demonstrates how knowledge can function as a driver of long-term economic growth. When annual economic growth of a few per cent accumulates over decades, it transforms people's lives. Previous macroeconomic research had emphasised technological innovation as the primary driver of economic growth, but had not modelled how economic decisions and market conditions determine the creation of new technologies. Paul Romer solved this problem by demonstrating how economic forces govern the willingness of firms to produce new ideas and innovations.

Romer's solution, which was published in 1990, laid the foundation of what is now called endogenous growth theory. The theory is both conceptual and practical, as it explains how ideas are different to other goods and require specific conditions to thrive in a market. Romer's theory has generated vast amounts of new research into the regulations and policies that encourage new ideas and long-term prosperity.
Climate change
Nordhaus' findings deal with interactions between society and nature. Nordhaus decided to work on this topic in the 1970s, as scientists had become increasingly worried about the combustion of fossil fuel resulting in a warmer climate. In the mid-1990s, he became the first person to create an integrated assessment model, i.e. a quantitative model that describes the global interplay between the economy and the climate. His model integrates theories and empirical results from physics, chemistry and economics. Nordhaus' model is now widely spread and is used to simulate how the economy and the climate co-evolve. It is used to examine the consequences of climate policy interventions, for example carbon taxes.

The contributions of Paul Romer and William Nordhaus are methodological, providing us with fundamental insights into the causes and consequences of technological innovation and climate change. This year's Laureates do not deliver conclusive answers, but their findings have brought us considerably closer to answering the question of how we can achieve sustained and sustainable global economic growth.
The Laureates:

William D. Nordhaus, born 1941 in Albuquerque, USA. Ph.D. in 1967 from Massachusetts Institute of Technology, Cambridge, USA. Sterling Professor of Economics, Yale University, New Haven, USA.

Paul M. Romer, born 1955 in Denver, USA. Ph.D. in 1983 from University of Chicago, USA. Professor at NYU Stern School of Business, New York, USA.

The Prize amount: 9 million Swedish krona, to be shared equally between the Laureates

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technology; alternative fuels; energy policy; environmental awareness; climate; global warming; economics; environmental policies; poverty and learning

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Nobel Prize in Economics 2018: Integrating innovation and climate with economic growth

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The 2018 Sveriges Riksbank Prize in Economic Sciences in Memory of Alfred Nobel is being awarded to William D. Nordhaus "for integrating climate change into long-run macroeconomic analysis" and Paul M. Romer "for integrating technological innovations into long-run macroeconomic analysis."

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Louis Goodman discovers nitrogen mustards can be used in the treatment of cancer. Goodman studied chemical warfare agents during WWII and published a paper reporting the use of nitrogen mustards as the first chemotherapeutic agents against Hodgkin's Disease, lymphosarcoma, and leukemias.1

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Researchers from Keele University have worked with an international team of astronomers to find for the first time that a white dwarf and a brown dwarf collided in a 'blaze of glory' that was witnessed on Earth in 1670.

Using the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, the international team of astronomers, including workers from the Universities of Keele, Manchester, South Wales, Arizona State, Minnesota, Ohio State, Warmia & Mazury, and the South African Astronomical Observatory, found evidence that a white dwarf (the remains of a star like the Sun at the end of its life) and a brown dwarf (a 'failed' star without sufficient mass to sustain thermonuclear fusion) collided in a short-lived blaze of glory that was witnessed on Earth in 1670 as Nova Cygni -- 'a new star below the head of the Swan.' The brown dwarf star was 'shredded' and dumped on the surface of a white dwarf star, leading to the 1670 eruption and the hourglass we see today.

In July of 1670, observers on Earth witnessed a 'new star', or nova, in the constellation Cygnus -- the Swan. Where previously there was no obvious star, there abruptly appeared a star as bright as those in the Plough, that gradually faded, reappeared, and finally disappeared from view.

Modern astronomers studying the remains of this cosmic event initially thought it was triggered by the merging of two main-sequence stars -- stars on the same evolutionary path as our Sun. This so-called 'new star' was long referred to as 'Nova Vulpeculae 1670', and later became known as CK Vulpeculae.

However, we now know that CK Vulpeculae was not what we would today describe as a 'nova', but is in fact the merger of two stars -- a white dwarf and a brown dwarf.

By studying the debris from this explosion -- which takes the form of dual rings of dust and gas, resembling an hourglass with a compact central object -- the research team concluded that a brown dwarf, a so-called failed star without the mass to sustain nuclear fusion, had merged with a white dwarf.

Professor Nye Evans, Professor of Astrophysics at Keele University and co-author on the paper appearing in the Monthly Notices of the Royal Astronomical Society explains:

"CK Vulpeculae has in the past been regarded as the oldest 'old nova'. However, the observations of CK Vulpeculae I have made over the years, using telescopes on the ground and in space, convinced me more and more that this was no nova. Everyone knew what it wasn't -- but nobody knew what it was! But a stellar merger of some sort seemed the best bet. With our ALMA observations of the exquisite dusty hourglass and the warped disc, plus the presence of lithium and peculiar isotope abundances, the jig-saw all fitted together: in 1670 a brown dwarf star was 'shredded' and dumped on the surface of a white dwarf star, leading to the 1670 eruption and the hourglass we see today."

The team of European, American and South African astronomers used the Atacama Large Millimeter/submillimeter Array to examine the remains of the merger, with some interesting findings. By studying the light from two, more distant, stars as they shine through the dusty remains of the merger, the researchers were able to detect the tell-tale signature of the element lithium, which is easily destroyed in stellar interiors.

Dr Stewart Eyres, Deputy Dean of the Faculty of Computing, Engineering and Science at the University of South Wales and lead author on the paper explains:

"The material in the hourglass contains the element lithium, normally easily destroyed in stellar interiors. The presence of lithium, together with unusual isotopic ratios of the elements C, N, O, indicate that an (astronomically!) small amount of material, in the form of a brown dwarf star, crashed onto the surface of a white dwarf in 1670, leading to thermonuclear 'burning', an eruption that led to the brightening seen by the Carthusian monk Anthelme and the astronomer Hevelius, and in the hourglass we see today."

Professor Albert Zijlstra, from The University of Manchester's School of Physics & Astronomy, co-author of the study, says:

"Stellar collisions are the most violent events in the Universe. Most attention is given to collisions between neutrons stars, between two white dwarfs -- which can give a supernova -- and star-planet collisions.

"But it is very rare to actually see a collision, and where we believe one occurred, it is difficult to know what kind of stars collided. The type we believe that happened here is a new one, not previously considered or ever seen before. This is an extremely exciting discovery."

Professor Sumner Starrfield, Regents' Professor of Astrophysics at Arizona State University comments:

"The white dwarf would have been about 10 times more massive than the brown dwarf, so as the brown dwarf spiralled into the white dwarf it would have been ripped apart by the intense tidal forces exerted by the white dwarf. When these two objects collided, they spilled out a cocktail of molecules and unusual element isotopes.

"These organic molecules, which we could not only detect with ALMA, but also measure how they were expanding into the surrounding environment, provide compelling evidence of the true origin of this blast. This is the first time such an event has been conclusively identified.

"Intriguingly, the hourglass is also rich in organic molecules such as formaldehyde (H2CO), methanol (CH3OH) and methanamide (NH2CHO). These molecules would not survive in an environment undergoing nuclear fusion and must have been produced in the debris from the explosion. This lends further support to the conclusion that a brown dwarf met its demise in a star-on-star collision with a white dwarf."

Since most star systems in the Milky Way are binary, stellar collisions are not that rare, the astronomers note.

Professor Starrfield adds:

"Such collisions are probably not rare and this material will eventually become part of a new planetary system, implying that they may already contain the building-blocks of organic molecules as they are forming."

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stars; eris (xena); galaxies; extrasolar planets; origin of life; early climate; evolution; fossils

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When is a nova not a nova? When a white dwarf and a brown dwarf collide

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Researchers from Keele University have worked with an international team of astronomers to find for the first time that a white dwarf and a brown dwarf collided in a 'blaze of glory' that was witnessed on Earth in 1670.

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New Planet Is Largest Discovered That Orbits Two Suns

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If you cast your eyes toward the constellation Cygnus, you'll be looking in the direction of the largest planet yet discovered around a double-star system. It's too faint to see with the naked eye, but a team led by astronomers from Goddard and San Diego State University, used NASA's Kepler Space Telescope to identify the new planet.

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human evolution, the process by which human beings developed on Earth from now-extinct primates. Viewed zoologically, we humans are Homo sapiens, a culture-bearing upright-walking species that lives on the ground and very likely first evolved in Africa about 315,000 years ago. We are now the only living members of what many zoologists refer to as the human tribe, Hominini, but there is abundant fossil evidence to indicate that we were preceded for millions of years by other hominins, such as Ardipithecus, Australopithecus, and other species of Homo, and that our species also lived for a time contemporaneously with at least one other member of our genus, H. neanderthalensis (the Neanderthals). In addition, we and our predecessors have always shared Earth with other apelike primates, from the modern-day gorilla to the long-extinct Dryopithecus. That we and the extinct hominins are somehow related and that we and the apes, both living and extinct, are also somehow related is accepted by anthropologists and biologists everywhere. Yet the exact nature of our evolutionary relationships has been the subject of debate and investigation since the great British naturalist Charles Darwin published his monumental books On the Origin of Species (1859) and The Descent of Man (1871). Darwin never claimed, as some of his Victorian contemporaries insisted he had, that "man was descended from the apes," and modern scientists would view such a statement as a useless simplification-just as they would dismiss any popular notions that a certain extinct species is the " missing link" between humans and the apes. There is theoretically, however, a common ancestor that existed millions of years ago. This ancestral species does not constitute a "missing link" along a lineage but rather a node for divergence into separate lineages. This ancient primate has not been identified and may never be known with certainty, because fossil relationships are unclear even within the human lineage, which is more recent. In fact, the human "family tree" may be better described as a "family bush," within which it is impossible to connect a full chronological series of species, leading to Homo sapiens, that experts can agree upon.
(Read T. H. Huxley's 1875 Britannica essay on evolution & biology.)
The primary resource for detailing the path of human evolution will always be fossil specimens. Certainly, the trove of fossils from Africa and Eurasia indicates that, unlike today, more than one species of our family has lived at the same time for most of human history. The nature of specific fossil specimens and species can be accurately described, as can the location where they were found and the period of time when they lived; but questions of how species lived and why they might have either died out or evolved into other species can only be addressed by formulating scenarios, albeit scientifically informed ones. These scenarios are based on contextual information gleaned from localities where the fossils were collected. In devising such scenarios and filling in the human family bush, researchers must consult a large and diverse array of fossils, and they must also employ refined excavation methods and records, geochemical dating techniques, and data from other specialized fields such as genetics, ecology and paleoecology, and ethology ( animal behaviour)-in short, all the tools of the multidisciplinary science of paleoanthropology.

This article is a discussion of the broad career of the human tribe from its probable beginnings millions of years ago in the Miocene Epoch (23 million to 5.3 million years ago [mya]) to the development of tool-based and symbolically structured modern human culture only tens of thousands of years ago, during the geologically recent Pleistocene Epoch (about 2.6 million to 11,700 years ago). Particular attention is paid to the fossil evidence for this history and to the principal models of evolution that have gained the most credence in the scientific community. See the article evolution for a full explanation of evolutionary theory, including its main proponents both before and after Darwin, its arousal of both resistance and acceptance in society, and the scientific tools used to investigate the theory and prove its validity.

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Human evolution | History, Stages, Timeline, Tree, Chart, & Facts

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Human evolution, the process by which human beings developed on Earth from now-extinct primates. The only extant members of the human tribe, Hominini, belong to the species Homo sapiens. The exact nature of the evolutionary relationships between modern humans and their ancestors remains the subject of debate.

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In 1543, while on his deathbed, Polish astronomer Nicholas Copernicus published his theory that the Sun is at the center of the solar system with the planets revolving around it. Before that, astronomers believed the Earth was at the center of the universe.

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Over the course of ages, we have made countless discoveries that have improved the quality of our life and helped us to understand the world around us. It is very difficult (if not impossible) to rank the importance of the discoveries we have made, but one thing is for sure - some of them have literally changed our life. From penicillin and the screw pump to X-rays and electricity, here are 25 Biggest Scientific Discoveries in History of Mankind.

Feature Image: shutterstock

On March 26, 1953, American medical researcher Jonas Salk announced that he had successfully tested a vaccine against poliomyelitis, the virus that causes the crippling disease of polio. In 1952, an epidemic year for polio, there were 58,000 new cases reported in the US and more than 3,000 deaths caused by the disease.

Enjoy this post? Check out 25 Most Fascinating Scientific Discoveries Of 2015.

Lists Going Viral Right Now

Photos: 23. WP, Planets2013, CC BY-SA 3.0, 22. Bryan Brandenburg, 21. David Hawgood via geographic.org.uk, 17. Ildar Sagdejev ( Specious), 2008-07-11 Air conditioners at UNC-CH, CC BY-SA 4.0, 12. © Nevit Dilmen, Medical X-Ray imaging FKJ04 nevit, CC BY-SA 3.0, 10. Sandbh, 18 column periodic table, with Lu and Lr in group 3, CC BY-SA 4.0, 9. AIRS via flickr, CC BY 2.0, 8. Mj-bird, HITACHI, Magnetic Resonance Imaging System, ECHELON OVAL,, CC BY-SA 3.0, 2. William Hook via flickr, CC BY-SA 2.0, 1. GDC Global via flickr, CC BY 2.0

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25 Biggest Scientific Discoveries In History Of Mankind

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From penicillin and the screw pump to X-rays and electricity, here are 25 Biggest Scientific Discoveries in History of Mankind.

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Super-Earth LHS 1140b

Only a few decades ago, the thought of any alien planets existing in the reaches of space were just hypothetical ideas. Now, we know of thousands of such planets - and today, scientists may have discovered the best candidate yet for alien life.

That candidate is an exoplanet orbiting a red dwarf star 40 light-years from Earth-what the international team of astronomers who discovered it have deemed a "super-Earth." Using ESO's HARPS instrument and a range of telescopes around the world, the astronomers located the exoplanet orbiting the dim star - LHS 1140 - within its habitable zone. This world passes in front of its parent stars as it orbits, has likely retained most of its atmosphere, and is a little larger and much more massive than the Earth. In short, super-Earth LHS 1140b is among the most exciting known subjects for atmospheric studies.

Although the faint red dwarf star LHS 1140b is ten times closer to its star than the Earth is to the Sun, because red dwarfs are much smaller and cooler than the Sun is, the super-Earth lies in the middle of the habitable zone and receives around half as much sunlight from its star as the Earth does.

"This is the most exciting exoplanet I've seen in the past decade," lead author Jason Dittmann of the Harvard-Smithsonian Center for Astrophysics said in an ESO science release. "We could hardly hope for a better target to perform one of the biggest quests in science - searching for evidence of life beyond Earth."

Life As We Know It

To support life as we know it, a planet must retain an atmosphere and have liquid surface water. When red dwarf stars are young, they emit radiation that can damage the atmospheres of planets around them. This planet's large size indicates that a magma ocean may have existed on its surface for eons, feeding steam into the atmosphere and replenishing the planet with water until well within the time the star had cooled to its current, steady glow. The astronomers estimate the planet is at least five billion years old, and deduce that it has a diameter of almost 18,000 kilometers (11,185 mi)- 1.4 times larger than that of the Earth. Its greater mass and density implies that it is probably made of rock with a dense iron core.

Two of the European members of the team, Xavier Delfosse and Xavier Bonfils, stated in the release: "The LHS 1140 system might prove to be an even more important target for the future characterization of planets in the habitable zone than Proxima b or TRAPPIST-1. This has been a remarkable year for exoplanet discoveries!"

Scientists expect observations with the Hubble Space Telescope will soon allow them to assess how much high-energy radiation the exoplanet receives, and further into the future - with the help of new telescopes like ESO's Extremely Large Telescope and the James Webb Telescope - detailed observations of the atmospheres of exoplanets will be possible.

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Scientists Just Discovered an Alien Planet That's The Best Candidate for Life As We Know It

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Only a few decades ago, the thought of any alien planets existing in the reaches of space were just hypothetical ideas. Now, we know of thousands of such planets - and today, scientists may have discovered the best candidate yet for alien life.

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The super star cluster Westerlund 1, only 15,000 light-years away in our Milky Way neighborhood, hosts one of the largest stars ever discovered.

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jeremy roos

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Plague is an infectious disease caused by the bacteria Yersinia pestis, a zoonotic bacteria, usually found in small mammals and their fleas. It is transmitted between animals through fleas. Humans can be infected through:

the bite of infected vector fleas

unprotected contact with infectious bodily fluids or contaminated materials

the inhalation of respiratory droplets/small particles from a patient with pneumonic plague.

Plague is a very severe disease in people, particularly in its septicaemic (systemic infection caused by circulating bacteria in bloodstream) and pneumonic forms, with a case-fatality ratio of 30% to 100% if left untreated. The pneumonic form is invariably fatal unless treated early. It is especially contagious and can trigger severe epidemics through person-to-person contact via droplets in the air.

Historically, plague was responsible for widespread pandemics with high mortality. It was known as the "Black Death" during the fourteenth century, causing more than 50 million deaths in Europe. Nowadays, plague is easily treated with antibiotics and the use of standard precautions to prevent acquiring infection.

Signs and symptoms

People infected with plague usually develop acute febrile disease with other non-specific systemic symptoms after an incubation period of one to seven days, such as sudden onset of fever, chills, head and body aches, and weakness, vomiting and nausea.

There are two main forms of plague infection, depending on the route of infection: bubonic and pneumonic.

Bubonic plague is the most common form of plague and is caused by the bite of an infected flea. Plague bacillus, Y. pestis, enters at the bite and travels through the lymphatic system to the nearest lymph node where it replicates itself. The lymph node then becomes inflamed, tense and painful, and is called a 'bubo'. At advanced stages of the infection the inflamed lymph nodes can turn into open sores filled with pus. Human to human transmission of bubonic plague is rare. Bubonic plague can advance and spread to the lungs, which is the more severe type of plague called pneumonic plague.

Pneumonic plague, or lung-based plague, is the most virulent form of plague. Incubation can be as short as 24 hours. Any person with pneumonic plague may transmit the disease via droplets to other humans. Untreated pneumonic plague, if not diagnosed and treated early, can be fatal. However, recovery rates are high if detected and treated in time (within 24 hours of onset of symptoms).

Where is plague found?

As an animal disease, plague is found in all continents, except Oceania. There is a risk of human plague wherever the presence of plague natural foci (the bacteria, an animal reservoir and a vector) and human population co-exist.

Plague epidemics have occurred in Africa, Asia, and South America; but since the 1990s, most human cases have occurred in Africa. The three most endemic countries are the Democratic Republic of Congo, Madagascar, and Peru. In Madagascar cases of bubonic plague are reported nearly every year, during the epidemic season (between September and April).

Diagnosing plague

Confirmation of plague requires lab testing. The best practice is to identify Y. pestis from a sample of pus from a bubo, blood or sputum. A specific Y. pestis antigen can be detected by different techniques. One of them is a laboratory validated rapid dipstick test now widely used in Africa and South America, with the support of WHO.

Treatment

Untreated pneumonic plague can be rapidly fatal, so early diagnosis and treatment is essential for survival and reduction of complications. Antibiotics and supportive therapy are effective against plague if patients are diagnosed in time. Pneumonic plague can be fatal within 18 to 24 hours of disease onset if left untreated, but common antibiotics for enterobacteria (gram negative rods) can effectively cure the disease if they are delivered early.

Prevention

Preventive measures include informing people when zoonotic plague is present in their environment and advising them to take precautions against flea bites and not to handle animal carcasses. Generally people should be advised to avoid direct contact with infected body fluids and tissues. When handling potentially infected patients and collecting specimens, standard precautions should apply.

Vaccination

WHO does not recommend vaccination, except for high-risk groups (such as laboratory personnel who are constantly exposed to the risk of contamination, and health care workers).

Managing plague outbreaks

Find and stop the source of infection. Identify the most likely source of infection in the area where the human case(s) was exposed, typically looking for clustered areas with large numbers of small animal deaths. Institute appropriate infection, prevention and control procedures. Institute vector control, then rodent control. Killing rodents before vectors will cause the fleas to jump to new hosts, this is to be avoided.

Protect health workers. Inform and train them on infection prevention and control. Workers in direct contact with pneumonic plague patients must wear standard precautions and receive a chemoprophylaxis with antibiotics for the duration of seven days or at least as long as they are exposed to infected patients.

Ensure correct treatment: Verify that patients are being given appropriate antibiotic treatment and that local supplies of antibiotics are adequate.

Isolate patients with pneumonic plague. Patients should be isolated so as not to infect others via air droplets. Providing masks for pneumonic patients can reduce spread.

Surveillance: identify and monitor close contacts of pneumonic plague patients and give them a seven-day chemoprophylaxis. Chemoprophylaxis should also be given to household members of bubonic plague patients.

Obtain specimens which should be carefully collected using appropriate infection, prevention and control procedures and sent to labs for testing.

Disinfection. Routine hand-washing is recommended with soap and water or use of alcohol hand rub. Larger areas can be disinfected using 10% of diluted household bleach (made fresh daily).

Ensure safe burial practices. Spraying of face/chest area of suspected pneumonic plague deaths should be discouraged. The area should be covered with a disinfectant-soaked cloth or absorbent material.

Surveillance and control

Surveillance and control requires investigating animal and flea species implicated in the plague cycle in the region and developing environmental management programmes to understand the natural zoonosis of the disease cycle and to limit spread. Active long-term surveillance of animal foci, coupled with a rapid response during animal outbreaks has successfully reduced numbers of human plague outbreaks.

In order to effectively and efficiently manage plague outbreaks it is crucial to have an informed and vigilant health care work force (and community) to quickly diagnose and manage patients with infection, to identify risk factors, to conduct ongoing surveillance, to control vectors and hosts, to confirm diagnosis with laboratory tests, and to communicate findings with appropriate authorities.

WHO Response

WHO aims to prevent plague outbreaks by maintaining surveillance and supporting at-risk countries to prepare. As the type of animal reservoir differs according to the region and influences the risk and conditions of human transmission, WHO has developed specific guidelines for the Indian sub-continent, South-America and Sub-Saharan Africa.

WHO works with ministries of health to support countries facing outbreaks for field control activities.

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Fact sheets on plague: key facts, signs and symptoms, diagnosing, treatment and prevention

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Researchers at Northwestern University and Washington University School of Medicine have developed the first example of a bioelectronic medicine: an implantable, biodegradable wireless device that speeds nerve regeneration and improves the healing of a damaged nerve.

The collaborators -- materials scientists and engineers at Northwestern and neurosurgeons at Washington University -- developed a device that delivers regular pulses of electricity to damaged peripheral nerves in rats after a surgical repair process, accelerating the regrowth of nerves in their legs and enhancing the ultimate recovery of muscle strength and control. The size of a dime and the thickness of a sheet of paper, the wireless device operates for about two weeks before naturally absorbing into the body.

The scientists envision that such transient engineered technologies one day could complement or replace pharmaceutical treatments for a variety of medical conditions in humans. This type of technology, which the researchers refer to as a "bioelectronic medicine," provides therapy and treatment over a clinically relevant period of time and directly at the site where it's needed, thereby reducing side effects or risks associated with conventional, permanent implants.

"These engineered systems provide active, therapeutic function in a programmable, dosed format and then naturally disappear into the body, without a trace," said Northwestern's John A. Rogers, a pioneer in bio-integrated technologies and a co-senior author of the study. "This approach to therapy allows one to think about options that go beyond drugs and chemistry."

Rogers is the Louis Simpson and Kimberly Querrey Professor of Materials Science and Engineering, Biomedical Engineering and Neurological Surgery in the McCormick School of Engineering and Northwestern University Feinberg School of Medicine.

The research will be published Oct. 8 in the journal Nature Medicine.

While the device has not been tested in humans, the findings offer promise as a future therapeutic option for nerve injury patients. For cases requiring surgery, standard practice is to administer some electrical stimulation during the surgery to aid recovery. But until now, doctors have lacked a means to continuously provide that added boost at various time points throughout the recovery and healing process.

"We know that electrical stimulation during surgery helps, but once the surgery is over, the window for intervening is closed," said co-senior author Dr. Wilson "Zack" Ray, an associate professor of neurosurgery, of biomedical engineering and of orthopedic surgery at Washington University. "With this device, we've shown that electrical stimulation given on a scheduled basis can further enhance nerve recovery."

Over the past eight years, Rogers and his lab have developed a complete collection of electronic materials, device designs and manufacturing techniques for biodegradable devices with a broad range of options that offer the potential to address unmet medical needs. When Ray and his colleagues at Washington University identified the need for electrical stimulation-based therapies to accelerate wound healing, Rogers and colleagues at Northwestern went to their toolbox and set to work.

They designed and developed a thin, flexible device that wraps around an injured nerve and delivers electrical pulses at selected time points for days before the device harmlessly degrades in the body. The device is powered and controlled wirelessly by a transmitter outside the body that acts much like a cellphone-charging mat. Rogers and his team worked closely with the Washington University team throughout the development process and animal validation.

The Washington University researchers then studied the bioelectronic device in rats with injured sciatic nerves. This nerve sends signals up and down the legs and controls the hamstrings and muscles of the lower legs and feet. They used the device to provide one hour per day of electrical stimulation to the rats for one, three or six days or no electrical stimulation at all, and then monitored their recovery for the next 10 weeks.

They found that any electrical stimulation was better than none at all at helping the rats recover muscle mass and muscle strength. In addition, the more days of electrical stimulation the rats received, the more quickly and thoroughly they recovered nerve signaling and muscle strength. No adverse biological effects from the device and its reabsorption were found.

"Before we did this study, we weren't sure that longer stimulation would make a difference, and now that we know it does, we can start trying to find the ideal time frame to maximize recovery," Ray said. "Had we delivered electrical stimulation for 12 days instead of six, would there have been more therapeutic benefit? Maybe. We're looking into that now."

By varying the composition and thickness of the materials in the device, Rogers and colleagues can control the precise number of days it remains functional before being absorbed into the body. New versions can provide electrical pulses for weeks before degrading. The ability of the device to degrade in the body takes the place of a second surgery to remove a non-biodegradable device, thereby eliminating additional risk to the patient.

"We engineer the devices to disappear," Rogers said. "This notion of transient electronic devices has been a topic of deep interest in my group for nearly 10 years -- a grand quest in materials science, in a sense. We are excited because we now have the pieces -- the materials, the devices, the fabrication approaches, the system-level engineering concepts -- to exploit these concepts in ways that could have relevance to grand challenges in human health."

The research study also showed the device can work as a temporary pacemaker and as an interface to the spinal cord and other stimulation sites across the body. These findings suggest broad utility, beyond just the peripheral nervous system.

The work was supported by DARPA, the Center for Bio-Integrated Electronics at Northwestern University and the National Science Foundation (grant nos. 1400169, 1534120 and 1635443).

Video: https://www.youtube.com/watch?time_continue=2&v=BoOlL5LPb7o

Journal Reference:

Jahyun Koo, Matthew R. MacEwan, Seung-Kyun Kang, Sang Min Won, Manu Stephen, Paul Gamble, Zhaoqian Xie, Ying Yan, Yu-Yu Chen, Jiho Shin, Nathan Birenbaum, Sangjin Chung, Sung Bong Kim, Jawad Khalifeh, Daniel V. Harburg, Kelsey Bean, Michael Paskett, Jeonghyun Kim, Zohny S. Zohny, Seung Min Lee, Ruoyao Zhang, Kaijing Luo, Bowen Ji, Anthony Banks, Hyuck Mo Lee, Younggang Huang, Wilson Z. Ray, John A. Rogers. Wireless bioresorbable electronic system enables sustained nonpharmacological neuroregenerative therapy. Nature Medicine, 2018; DOI: 10.1038/s41591-018-0196-2

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medical devices; wounds and healing; neuropathy; alternative medicine; electronics; energy technology; medical technology; technology

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First example of a bioelectronic medicine: Biodegradable implant provides electrical stimulation that speeds nerve regeneration

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Researchers have developed the first example of a bioelectronic medicine: an implantable, biodegradable wireless device that speeds nerve regeneration and improves healing of a damaged nerve. Their device delivered pulses of electricity to damaged nerves in rats after a surgical repair process, accelerating the regrowth of nerves and enhancing the recovery of muscle strength and control.

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Hubble Space Telescope image of largest known population of globular clusters, in Abell 1689 galaxy grouping. Image Credit: NASA/ESA

NASA's Hubble Space Telescope has uncovered the largest known population of globular star clusters, an estimated 160,000, swarming like bees inside the crowded core of the giant grouping of galaxies known as Abell 1689.

An international team of astronomers used Hubble's Advanced Camera for Surveys to discover this bounty of stellar fossils and confirm such compact groupings can be used as reliable tracers for dark matter, the invisible gravitational scaffolding on which galaxies are built.

"We show how the relationship between globular clusters and dark matter depends on the distance from the center of the galaxy grouping," Karla Alamo-Martinez of the Center for Radio Astronomy and Astrophysics of the National Autonomous University of Mexico in Morelia. "In other words, if you know how many globular clusters are within a certain distance, we can give you an estimate of the amount of dark matter."

Alamo-Martinez is lead author of a paper on the findings published online Sept. 10 and appearing in the Sept. 20 print edition of The Astrophysical Journal, and part of a team led by John Blakeslee of National Research Council Canada's Herzberg Institute of Astrophysics at the Dominion Radio Astrophysical Observatory in Victoria, British Columbia.

Globular clusters, dense bunches of hundreds of thousands of stars, are the homesteaders of galaxies. They contain some of the oldest surviving stars in the universe. Almost 95 percent of globular cluster formation occurred within the first 1 billion to 2 billion years after our universe was born in the theorized Big Bang 13.8 billion years ago.

Studying globular clusters is critical to understanding the early, intense star-forming events that mark galaxy formation. Understanding dark matter can yield clues on how large structures such as galaxies and galaxy clusters were assembled billions of years ago.

The globular star cluster in Abell 1689 is roughly twice as large as any other population found in previous globular cluster surveys -- in comparison, our Milky Way galaxy hosts about 150 -- and constitutes the most distant such systems ever studied, at 2.25 billion light-years away. The Hubble study shows most of the globular clusters in Abell 1689 formed near the center of the galaxy grouping, which contains a deep well of dark matter. The farther away from the galaxy core Hubble looked, the fewer globular clusters it detected. This observation corresponded with a comparable drop in the amount of dark matter, based on previous research.

"The globular clusters are fossils of the earliest star formation in Abell 1689, and our work shows they were very efficient in forming in the denser regions of dark matter near the center of the galaxy cluster," Blakeslee said. "Our findings are consistent with studies of globular clusters in other galaxy clusters, but extend our knowledge to regions of higher dark matter density."

Peering deep inside the heart of Abell 1689, Hubble detected the visible-light glow of 10,000 globular clusters, some as dim as 29th magnitude, which is 1 one-billionth the faintness of the dimmest star that can be seen with the naked eye. Based on that number, Blakeslee's team estimated that more than 160,000 globular clusters are huddled within a diameter of 2.4 million light-years.

"Even though we are looking deep into the cluster, we're only seeing the brightest globular clusters, and only near the center of Abell 1689 where Hubble was pointed," he said.

For images and more information about the Abell 1689, visit:
http://www.nasa.gov/hubble
or
http://hubblesite.org/news/2013/36
-end-

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Hubble Uncovers Largest Known Group of Star Clusters, Clues to Dark Matter

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Hubble Space Telescope image of largest known population of globular clusters, in Abell 1689 galaxy grouping. Image Credit: NASA/ESA NASA's Hubble Space Telescope has uncovered the largest known population of globular star clusters, an estimated 160,000, swarming like bees inside the crowded core of the giant grouping of galaxies known as Abell 1689.

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The image above is an extreme close-up of a common British insect called a planthopper. You're looking at it from below, at the point where its two hind legs connect to its body. In the middle, you can clearly see that the top of each leg has a row of small teeth, which interlock together. As the planthopper jumps, the teeth ensure that its legs rotate together and extend at the same time.

This insect has gears.

GEARS!

It's a steampunk bug!

The gears are found on many young planthoppers but Gregory Sutton from the University of Cambridge first discovered them on a common British species called Issus coeleoptratus. "We didn't have to go to some obscure monastery in Outer Slaubvinia to find these things," he says. "We had to go to a place called The Garden, in The Backyard. Either the most complicated gearing in nature happens to be in our backyard, or there is stuff that's vastly more intricate and complicated that hasn't been found yet."

Sutton has been working with Malcolm Burrows from the University of Cambridge for the last 10 years, to study the movements of jumping insects like fleas, locusts, leafhoppers and pygmy mole crickets. When they filmed young planthoppers taking off, they saw that the hind legs would always move within 30 microseconds (millionths of a second) of each other. Such extreme coordination makes sense-the slightest difference in timing would send the insects spinning off to the side. But how could they achieve such tightly synchronised movements?

The nervous system can't be involved. In 30 microseconds, a neuron can barely begin to fire, much less trigger something that tweaks the insect's movements.

The answer lies on the insect's undersides. Back in the 1950s, other scientists noted that young planthoppers have small bumps on their trochanters-the first segment of the legs, which connect to the hip-like coxa. They were only found on the hind legs, and not the other pairs. No one knew what they were for. No one seemed to care. "It was one of those odd little footnotes in anatomical books," says Sutton.

Burrows and Sutton discovered the function of the bumps by planthoppers that had been restrained on their backs. The insects would try to jump whenever the duo gently prodded their abdomens. Just before their legs shot out, their trochanters would squeeze together. The bumps engaged and rolled against each other, exactly like man-made gears. "I was gobsmacked," says Sutton.

Gears allow two machines to rotate together in opposite directions. That's exactly what the planthopper's trochanter bumps do. Sutton tested this by pulling on the tendons of its jumping muscles with some forceps ("It's the Serious Edition of Operation ", he says.). Even if he only pulled one tendon, both legs would extend because the gears transmitted the motion of one trochanter into the other.

"Then, we got really lucky because we saw a few jumps where the gears wouldn't engage perfectly," says Sutton. When this happened, one leg was partially extended before the gears finally snagged and the planthopper's nigh-perfect coordination was ruined.

Wait! It gets better. These gears are training wheels!

The planthopper nymphs lose them when they become adults. But the adults don't shoot off in uncoordinated spins-if anything, they're better jumpers than the youngsters. Their hind trochanters make much closer contact with each other, and Sutton thinks that the friction between them helps to keep them in time. "We're kind of sure about that, but not entirely sure," he says.

"This is to our knowledge the first time that proper, engaging, counter-rotating gears have been seen in the animal kingdom," says Sutton. Crocodiles have cog-like teeth in their heart valves, and the wheel bug and cog-wheel turtle have teeth on their shells. But none of these structures actually act like gears. "You never see one cog-wheel turtle sidle up next to another, engage their shells, and spin in opposite directions," says Sutton. "If you did, I want you to call me. If I see that on your website, and I haven't been called, I will be an angry man."

The discovery is astounding in itself, but Sutton-a mechanical engineer-thinks that they could help us to make more effective machines at incredibly small scales. The teeth of most modern gears harken back to the 18th century, when mathematician Leonhard Euler designed a shape that could be easily cut by a machine. It's called an involute and it looks like a hill with a plateau at the top. It has been a standard part of gears ever since.

But the planthopper's gear teeth look more like a shark fin. "What we have is a prototype for a tooth shape for a high-speed, one-directional gear that's not constrained by the machining techniques of the 18th century," says Sutton.

Modern machines, such as 3-D printers, could easily create gears with these shark-fin teeth. Sutton is really excited by the prospect, and suspects that they may perform better in very small machines. "Modern machinery often doesn't work at very small scales," he says. "Friction doesn't matter so much when you have two big gears next to each other but when you get small, friction starts killing you."

The planthoppers might help to solve that problem. "We're still being impressed and shocked by what we find in the back garden," says Sutton.

Reference: Burrows & Sutton. 2013. Interacting Gears Synchronize Propulsive Leg Movements in a Jumping Insect. Science http://dx.doi.org/10.1126/science.1240284

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The image above is an extreme close-up of a common British insect called a planthopper. You're looking at it from below, at the point where its two hind legs connect to its body. In the middle, you can clearly see that the top of each leg has a row of small teeth, which interlock together.

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Newton’s third law of motion describes the nature of a force as the result of a mutual and simultaneous interaction between an object and a second object in its surroundings. This interaction results in a simultaneously exerted push or pull upon both objects involved in the interaction.

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Find out everything there is to know about NASA and stay updated on the latest space and NASA news with the comprehensive articles, interactive features and NASA pictures at LiveScience.com. Learn more about space and astronauts as NASA's amazing discoveries are reported.

Related Topics: Technology, Robots, Drones, Military Weapons, Spy Tech and Defense News

Copyright © All Rights Reserved.

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NASA News - 2018 Space Discoveries and Theories

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Find out everything there is to know about NASA and stay updated on the latest space and NASA news with the comprehensive articles, interactive features and NASA pictures at LiveScience.com. Learn more about space and astronauts as NASA's amazing discoveries are reported.

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Discovery became the third operational orbiter to enter service, preceded by and Challenger . It embarked on its last mission, STS-133, on February 24, 2011 and touched down for the final time at Kennedy Space Center on March 9, having spent a cumulative total of almost a full year in space.

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A team recovers NASA's Antarctic Impulsive Transient Antenna (ANITA) after a successful flight.

Credit: Australian Antarctic Division

There's something mysterious coming up from the frozen ground in Antarctica, and it could break physics as we know it.

Physicists don't know what it is exactly. But they do know it's some sort of cosmic ray - a high-energy particle that's blasted its way through space, into the Earth, and back out again. But the particles physicists know about - the collection of particles that make up what scientists call the Standard Model (SM) of particle physics - shouldn't be able to do that. Sure, there are low-energy neutrinos that can pierce through miles upon miles of rock unaffected. But high-energy neutrinos, as well as other high-energy particles, have "large cross-sections." That means that they'll almost always crash into something soon after zipping into the Earth and never make it out the other side.

And yet, since March 2016, researchers have been puzzling over two events in Antarctica where cosmic rays did burst out from the Earth, and were detected by NASA's Antarctic Impulsive Transient Antenna (ANITA) - a balloon-borne antenna drifting over the southern continent.

ANITA is designed to hunt cosmic rays from outer space, so the high-energy neutrino community was buzzing with excitement when the instrument detected particles that seemed to be blasting up from Earth instead of zooming down from space. Because cosmic rays shouldn't do that, scientists began to wonder whether these mysterious beams are made of particles never seen before.

Since then, physicists have proposed all sorts of explanations for these "upward going" cosmic rays, from sterile neutrinos (neutrinos that rarely ever bang into matter) to " atypical dark matter distributions inside the Earth," referencing the mysterious form of matter that doesn't interact with light [ The 18 Biggest Unsolved Mysteries in Physics]

All the explanations were intriguing, and suggested that ANITA might have detected a particle not accounted for in the Standard Model. But none of the explanations demonstrated conclusively that something more ordinary couldn't have caused the signal at ANITA.

A new paper uploaded today (Sept. 26) to the preprint server arXiv changes that. In it, a team of astrophysicists from Penn State University showed that there have been more upward-going high-energy particles than those detected during the two ANITA events. Three times, they wrote, IceCube (another, larger neutrino observatory in Antarctica) detected similar particles, though no one had yet connected those events to the mystery at ANITA. And, combining the IceCube and ANITA data sets, the Penn State researchers calculated that, whatever particle is bursting up from the Earth, it has much less than a 1-in-3.5 million chance of being part of the Standard Model. (In technical, statistical terms, their results had confidences of 5.8 and 7.0 sigma, depending on which of their calculations you're looking at.)

Derek Fox, the lead author on the new paper, said that he first came across the ANITA events in May 2018, in one of the earlier papers attempting to explain them.

"I was like, 'Well this model doesn't make much sense,'" Fox told Live Science, "but the [ANITA] result is very intriguing, so I started checking up on it. I started talking to my office neighbor Steinn Sigurdsson [the second author on the paper, who is also at Penn State] about whether maybe we could gin up some more plausible explanations than the papers that have been published to date."

Fox, Sigurdsson and their colleagues started looking for similar events in data collected by other detectors. When they came across possible upward-going events in IceCube data, he said, he realized that he might have come across something really game-changing for physics. [ 5 Mysterious Particles Lurking Underground]

The surface facility for the IceCube experiment, which is located under nearly 1 mile (1.6 kilometers) of ice in Antarctica. IceCube suggests ghostly neutrinos don't exist, but a new experiment says they do.

Credit: Courtesy of IceCube Neutrino Observatory

"That's what really got me going, and looking at the ANITA events with the utmost seriousness," he said, later adding, "This is what physicists live for. Breaking models, setting new constraints [on reality], learning things about the universe we didn't know."

As Live Science has previously reported, experimental, high-energy particle physics has been at a standstill for the last several years. When the 17-mile (27 kilometers), $10 billion Large Hadron Collider (LHC) was completed on the border between France and Switzerland in 2009, scientists thought it would unlock the mysteries of supersymmetry - the mysterious, theoretical class of particles that scientists suspect might exist outside of current physics, but had never detected. According to supersymmetry, every existing particle in the Standard Model has a supersymmetric partner. Researchers suspect these partners exist because the masses of known particles are out of wack - not symmetric with one another.

"Even though the SM works very well in explaining a plethora of phenomena, it still has many handicaps," said Seyda Ipek, a particle physicist at UC Irvine, who was not involved in the current research. "For example, it cannot account for the existence of dark matter, [explain mathematical weirdness in] neutrino masses, or the matter-antimatter asymmetry of the universe."

Instead, the LHC confirmed the Higgs boson, the final undetected part of the Standard Model, in 2012. And then it stopped detecting anything else that important or interesting. Researchers began to question whether any existing physics experiment could ever detect a supersymmetric particle.

"We need new ideas," Jessie Shelton, a theoretical physicist at the University of Illinois at Urbana-Champaign, told Live Science in May, around the same time that Fox first became interested in the ANITA data.

Now, several scientists not involved in the Penn State paper told Live Science that it offers solid (if incomplete) evidence that something new has really arrived.

"It was clear from the start that if the ANITA anomalous events are due to particles that had propagated through thousands of kilometers of Earth, then those particles were very likely not SM particles," said Mauricio Bustamante, an astrophysicist at the Niels Bohr Institute at the University of Copenhagen, who was not an author on the new paper.

"The paper that appeared today is the first systematic calculation of how unlikely is that these events were due to SM neutrinos," he added. "Their result strongly disfavors a SM explanation."

"I think it's very compelling," said Bill Louis, a neutrino physicist at Los Alamos National Laboratory who was not involved in the paper and has been following research into the ANITA events for several months.

If standard model particle created these anomalies, they should have been neutrinos. Researchers know that both because of the particles they decayed into, and because no other standard model particle would even have a fragment of a chance in a million of making it through the Earth.

But neutrinos of this energy, Louis said, just shouldn't make it through the Earth often enough for ANITA or IceCube to detect. It's not how they work. But neutrino detectors like ANITA and IceCube don't detect neutrinos directly. Instead, they detect the particles that neutrinos decay into after smashing into Earth's atmosphere or Antarctic ice. And there are other events that can generate those particles, triggering the detectors. This paper strongly suggests that those events must have been supersymmetric, Louis said, though he added that more data is necessary.

Fox and his colleagues went on to argue that the particles are most likely to be a sort of theoretical supersymmetric particle called "stau sleptons." Stau sleptons are supersymmetric versions of a Standard Model particle called the tau lepton. The "S" is for "supersymmetric" (really). [ Sparticles to Neutrinos: The Coolest Little Particles in the Universe]

Louis said that at this stage he thinks that level of specificity is "a bit of a stretch."

The authors make a strong statistical case that no conventional particle would be likely to travel through the Earth in this way, he said, but there isn't yet enough data to be certain. And there's certainly not enough that they could definitively figure out what particle made the trip.

Fox didn't dispute that.

"As an observer, there's no way that I can know that this is a stau," he said. "From my perspective, I go trawling around trying to discover new things about the universe, I come upon some really bizarre phenomenon, and then with my colleagues, we do a little literature search to see if anybody has ever thought that this might happen. And then if we find papers in the literature, including one from 14 years ago that predict something just like this phenomenon, then that gets really high weight from me."

He and his colleagues did find a long chain of papers from theorists predicting that stau sleptons might turn up like this in neutrino observatories. And because those papers were written before the ANITA anomaly, Fox said, that suggests strongly to him that those theorists were onto something.

But there remains a lot of uncertainty on that front, he said. Right now, researchers just know that whatever this particle is, it interacts very weakly with other particles, or else it would have never survived the trip through the planet's dense mass.

Every physicist who spoke with Live Science agreed that researchers need to collect more data to verify that ANITA and IceCube have cracked supersymmetry. It's possible, Fox said, that when IceCube researchers dig into their data archives they'll find more, similar events that had previously gone unnoticed. Louis and Bustamante both said that NASA should run more ANITA flights to see if similar upward-going particles turn up.

"For us to be certain that these events are not due to unknown unknowns - say, unmapped properties of the Antarctic ice - we would like other instruments to also detect these sort of events," Bustamante said.

Over the long-term, if these results are confirmed and the details of what particle is causing them are nailed down, several researchers said that the ANITA anomaly might unlock even more new physics at the LHC.

"Any observation a non-SM particle would be a game changer, because it would tell us which path we should take after the SM," Ipek said. "The type of [supersymmetric] particle they claim to have produced the signals of, sleptons, are very hard to produce and detect at LHC."

"So, it is very interesting if they can be observed by other types of experiments. Of course, if this is true, then we will expect a ladder of other [supersymmetric] particles to be observed at the LHC, which would be a complementary test of the claims."

In other words, the ANITA anomalies could offer scientists the key information necessary to properly tune the LHC to unlock more of supersymmetry. Those experiments might even turn up an explanation for dark matter.

Right now, Fox said, he's just hungry for more data.

Originally published on Live Science.

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Bizarre Particles Keep Flying Out of Antarctica's Ice, and They Might Shatter Modern Physics

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There's something mysterious coming up from the frozen ground in Antarctica, and it could break physics as we know it. Physicists don't know what it is exactly. But they do know it's some sort of cosmic ray - a high-energy particle that's blasted its way through space, into the Earth, and back out again.

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This history of the telephone chronicles the development of the electrical telephone, and includes a brief overview of its predecessors. The first telephone patent was granted to Alexander Graham Bell in 1869.

Actor portraying Ethan William Ward in a 1932 silent film. Shows Bell's second telephone transmitter (microphone), invented 1876 and first displayed at the Centennial Exposition, Philadelphia.

A 19th century acoustic tin can or "lovers' telephone"

Before the invention of electromagnetic telephones, mechanical acoustic devices existed for transmitting speech and music over a greater distance. This distance was greater than that of normal direct speech. The earliest mechanical telephones were based on sound transmission through pipes or other physical media.[1] The acoustic tin can telephone, or "lovers' phone", has been known for centuries.[1] It connects two diaphragms with a taut string or wire, which transmits sound by mechanical vibrations from one to the other along the wire (and not by a modulated electric current). The classic example is the children's toy made by connecting the bottoms of two paper cups, metal cans, or plastic bottles with tautly held string.[1][2]

Some of the earliest known experiments were conducted by the British physicist and polymath, Robert Hooke, from 1664 to 1685.[1][3] An acoustic string phone made in 1667 has been attributed to him.[4] An early version was also found in use by the Chimu in Peru. The gourd and stretched-hide version resides in the Smithsonian Museum collection and dates back to around the 7th century AD.[5]

For a few years in the late 1800s, acoustic telephones were marketed commercially as a competitor to the electrical telephone. When the Bell telephone patents expired and many new telephone manufacturers began competing, acoustic telephone makers quickly went out of business. Their maximum range was very limited.[2] An example of one such company was the Pulsion Telephone Supply Company created by Lemuel Mellett in Massachusetts, which designed its version in 1888 and deployed it on railroad right-of-ways.

Additionally, speaking tubes have long been common, especially within buildings and aboard ships, and they are still in use today.[6]

The telephone emerged from the making and successive improvements of the electrical telegraph. In 1804, Spanish polymath and scientist Francisco Salva Campillo constructed an electrochemical telegraph.[7] The first working telegraph was built by the English inventor Francis Ronalds in 1816 and used static electricity.[8] An electromagnetic telegraph was created by Baron Schilling in 1832. Carl Friedrich Gauss and Wilhelm Weber built another electromagnetic telegraph in 1833 in Göttingen. At the University of Göttingen, the two had been working together in the field of magnetism. They built the first telegraph to connect the observatory and the Institute of physics, which was able to send eight words per minute.[9]

Bell prototype telephone stamp
Centennial Issue of 1976

The electrical telegraph was first commercialized by Sir William Fothergill Cooke and entered use on the Great Western Railway in England. It ran for 13 mi (21 km) from Paddington station to West Drayton and came into operation on April 9, 1839.

Another electrical telegraph was independently developed and patented in the United States in 1837 by Samuel Morse. His assistant, Alfred Vail, developed the Morse code signaling alphabet with Morse. America's first telegraph was sent by Morse on January 6, 1838, across 2 miles (3 km) of wiring.

Credit for the invention of the electric telephone is frequently disputed, and new controversies over the issue have arisen from time to time. Antonio Meucci, Alexander Graham Bell, and Elisha Gray amongst others, have all been credited with the telephone's invention. The early history of the telephone became and still remains a confusing morass of claims and counterclaims, which were not clarified by the huge number of lawsuits filed in order to resolve the patent claims of the many individuals and commercial competitors. The Bell and Edison patents, however, were commercially decisive, because they dominated telephone technology and were upheld by court decisions in the United States.

Antonio Meucci, 1854, constructed telephone-like devices.

Alexander Graham Bell was awarded the first U.S. patent for the invention of the telephone in 1876.

The modern telephone is the result of the work of many people. Alexander Graham Bell was, however, the first to patent the telephone, as an "apparatus for transmitting vocal or other sounds telegraphically". Bell has most often been credited as the inventor of the first practical telephone. Johann Philipp Reis coined the term "telephon". Models of it were sent abroad, to London, Dublin, Tiflis, and other places. It became a subject for popular lectures, and an article for scientific cabinets. Edison credited him as the "first inventor of the telephone." The Italian-American inventor and businessman Antonio Meucci has been recognized by the U.S. House of Representatives for his contributory work on the telephone. Several other controversies also surround the question of priority of invention for the telephone.

The Elisha Gray and Alexander Bell telephone controversy considers the question of whether Bell and Gray invented the telephone independently and, if not, whether Bell stole the invention from Gray. This controversy is narrower than the broader question of who deserves credit for inventing the telephone, for which there are several claimants.

The Canadian Parliamentary Motion on Alexander Graham Bell article reviews the controversial June 2002 United States House of Representatives resolution recognizing Meucci's contributionsthe invention of the telephone (not 'for' the invention of the telephone). The same resolution was not passed in the U.S. Senate, thus labeling the House resolution as "political rhetoric". A subsequent counter-motion was unanimously passed in Canada's Parliament 10 days later which declared Bell its inventor. This webpage examines critical aspects of both the parliamentary motion and the congressional resolution.

The main users of the electrical telegraph were post offices, railway stations, the more important governmental centers (ministries), stock exchanges, very few nationally distributed newspapers, the largest internationally important corporations, and wealthy individuals.

Telegraph exchanges worked mainly on a store and forward basis. Although telephones devices were in use before the invention of the telephone exchange, their success and economical operation would have been impossible with the schema and structure of the contemporary telegraph systems.

Prior to the invention of the telephone switchboard, pairs of telephones were connected directly with each other, which was primarily useful for connecting a home to the owner's business (They practically functioned as a primitive intercom). A telephone exchange provides telephone service for a small area. Either manually by operators, or automatically by machine switching equipment, it interconnects individual subscriber lines for calls made between them. This made it possible for subscribers to call each other at homes, businesses, or public spaces. These made telephones an available and comfortable communication tool for many purposes, and it gave the impetus for the creation of a new industrial sector.

The telephone exchange was an idea of the Hungarian engineer Tivadar Puskás (1844-1893) in 1876, while he was working for Thomas Edison on a telegraph exchange. The first commercial telephone exchange was opened at New Haven, Connecticut, with 21 subscribers on 28 January 1878, in a storefront of the Boardman Building in New Haven, Connecticut. George W. Coy designed and built the world's first switchboard for commercial use. Coy was inspired by Alexander Graham Bell's lecture at the Skiff Opera House in New Haven on 27 April 1877.

In Bell's lecture, during which a three-way telephone connection with Hartford and Middletown, Connecticut, was demonstrated, he first discussed the idea of a telephone exchange for the conduct of business and trade. On 3 November 1877, Coy applied for and received a franchise from the Bell Telephone Company for New Haven and Middlesex Counties. Coy, along with Herrick P. Frost and Walter Lewis, who provided the capital, established the District Telephone Company of New Haven on 15 January 1878.

The switchboard built by Coy was, according to one source, constructed of "carriage bolts, handles from teapot lids and bustle wire." According to the company records, all the furnishings of the office, including the switchboard, were worth less than forty dollars. While the switchboard could connect as many as sixty-four customers, only two conversations could be handled simultaneously and six connections had to be made for each call.

The District Telephone Company of New Haven went into operation with only twenty-one subscribers, who paid $1.50 per month. By 21 February 1878, however, when the first telephone directory was published by the company, fifty subscribers were listed. Most of these were businesses and listings such as physicians, the police, and the post office; only eleven residences were listed, four of which were for persons associated with the company.

The New Haven District Telephone Company grew quickly and was reorganized several times in its first years. By 1880, the company had the right from the Bell Telephone Company to service all of Connecticut and western Massachusetts. As it expanded, the company was first renamed Connecticut Telephone, and then Southern New England Telephone in 1882. The site of the first telephone exchange was granted a designation as a National Historic Landmark on 23 April 1965. However it was withdrawn in 1973 in order to demolish the building and construct a parking garage.

The following is a brief summary of the history of the development of the telephone:

A French Gower telephone of 1912 at the Musée des Arts et Métiers in Paris

Early 7th century AD - Chimu culture in Peru invents a string telephone using gourds and stretched hide. The original artifact is in the Smithsonian's National Museum of the American Indian storage facility in Suitland, Maryland.

1667: Robert Hooke invents a string telephone that conveys sounds over an extended wire by mechanical vibrations. It was to be termed an 'acoustic' or 'mechanical' (non-electrical) telephone.

1753: Charles Morrison proposes the idea that electricity can be used to transmit messages, by using different wires for each letter.[22]

1844: Innocenzo Manzetti first moots the idea of a "speaking telegraph" (telephone).

1854: Charles Bourseul writes a memorandum on the principles of the telephone. (See the article: "Transmission électrique de la parole", L'Illustration, Paris, 26 August 1854.)

1854: Antonio Meucci demonstrates an electric voice-operated device in New York; exactly what kind of device he demonstrates is unknown.

1861: Philipp Reis constructs the first speech-transmitting telephone

28 December 1871: Antonio Meucci files a patent caveat (No. 3353, a notice of intent to invent, but not a formal patent application) at the U.S. Patent Office for a device he names a "Sound Telegraph".[23]

1872: Elisha Gray establishes Western Electric Manufacturing Company.

1 July 1875: Bell uses a bi-directional "gallows" telephone that is able to transmit "voicelike sounds", but not clear speech. Both the transmitter and the receiver are identical membrane electromagnet instruments.

1875: Thomas Edison experiments with acoustic telegraphy and in November builds an electro-dynamic receiver, but does not exploit it.

1875: Hungarian Tivadar Puskás (the inventor of the telephone exchange) arrives in the USA.

6 April 1875: Bell's U.S. Patent 161,739 "Transmitters and Receivers for Electric Telegraphs" is granted. This uses multiple vibrating steel reeds in make-break circuits, and the concept of multiplexed frequencies.

20 January 1876: Bell signs and notarizes his patent application for the telephone.

11 February 1876: Elisha Gray designs a liquid transmitter for use with a telephone, but does not build one.

7 March 1876: Bell's U.S. patent No. 174,465 for the telephone is granted.

10 March 1876: Bell transmits the sentence: "Mr. Watson, come here! I want to see you!" using a liquid transmitter and an electromagnetic receiver.

10 August 1876: Using the telegraph line between Brantford and Paris, Ontario, eight miles (thirteen kilometres) distant, Bell makes a telephone call, said by some to be the "world's first long-distance call".[24]

30 January 1877: Bell's U.S. patent No. 186,787 is granted for an electromagnetic telephone using permanent magnets, iron diaphragms, and a call bell.

27 April 1877: Edison files for a patent on a carbon (graphite) transmitter. Patent No. 474,230 is granted on 3 May 1892, after a 15-year delay because of litigation. Edison is later granted patent No. 222,390 for a carbon granules transmitter in 1879.

6 October 1877: Scientific American publishes the invention from Bell-at that time still without a ringer.

25 October 1877: the article in Scientific American is discussed at the Telegraphenamt in Berlin

12 November 1877: The first commercial telephone company enters telephone business in Friedrichsberg close to Berlin[25] using the Siemens pipe as ringer and telephone devices built by Siemens.

1877: The first experimental Telephone Exchange is established in Boston.

1877: First long-distance telephone line

1877: Emile Berliner invents the telephone transmitter.

14 January 1878: Bell demonstrates the telephone to Queen Victoria and makes the first publicly witnessed long-distance calls in the UK. The queen tries the device and finds it to be "quite extraordinary".[26]

26 January 1878: The first permanent telephone connection in the UK is made between two businesses in Manchester

28 January 1878: The first commercial US telephone exchange opens in New Haven, Connecticut.

15 June 1878: The first commercial toll line enters operation, connecting Springfield and Holyoke, Massachusetts[27]

1887: Tivadar Puskás introduces the multiplex switchboard, that has an epochal significance in the further development of telephone exchanges.[28]

1915: The first U.S. coast-to-coast long-distance telephone call, is ceremonially inaugurated by A.G. Bell in New York City and his former assistant Thomas Augustus Watson in San Francisco, California.

1927: The first transatlantic phone call is made, from the United States to the United Kingdom.[29]

Early telephones were technically diverse. Some of them used liquid transmitters which soon went out of use. Others were dynamic: their diaphragms vibrated a coil of wire in the field of a permanent magnet or vice versa. Such sound-powered telephones survived in small numbers through the 20th century in military and maritime applications where the ability to create its own electrical power was crucial. Most, however, used Edison/Berliner carbon transmitters, which were much louder than the other kinds, even though they required induction coils, actually acting as impedance matching transformers to make it compatible to the line impedance. The Edison patents kept the Bell monopoly viable into the 20th century, by which time telephone networks were more important than the instrument.

Early telephones were locally powered by a dynamic transmitter. One of the jobs of outside plant personnel was to visit each telephone periodically to inspect the battery. During the 20th century, the " common battery" operation came to dominate, and was powered by the "talk battery" from the telephone exchange over the same wires that carried the voice signals. Late in the century, wireless handsets brought a revival of local battery power.

The earliest telephones had only one wire for transmitting and receiving of audio, and used a ground return path. The earliest dynamic telephones also had only one opening for sound, and the user listened and spoke into the same hole. Sometimes the instruments were operated in pairs at each end, making conversation more convenient but also more expensive.

At first, telephones were leased in pairs to the subscriber, for example one for his home and one for his shop, and the subscriber had to arrange with telegraph contractors to construct a line between them. Users who wanted the ability to speak to three or four different shops, suppliers etc. would obtain and set up three or four pairs of telephones. Western Union, already using telegraph exchanges, quickly extended the principle to its telephones in New York City and San Francisco, and Bell was not slow in appreciating the potential.

Signaling began in an appropriately primitive manner. The user alerted the other end, or the exchange operator, by whistling into the transmitter. Exchange operation soon resulted in telephones being equipped with a bell, first operated over a second wire and later with the same wire using a condenser. Telephones connected to the earliest Strowger automatic exchanges had seven wires, one for the knife switch, one for each telegraph key, one for the bell, one for the push button and two for speaking.

Rural and other telephones that were not on a common battery exchange had hand cranked " magneto" generators to produce an alternating current to ring the bells of other telephones on the line and to alert the exchange operator.

In 1877 and 1878, Edison invented and developed the carbon microphone used in all telephones along with the Bell receiver until the 1980s. After protracted patent litigation, a federal court ruled in 1892 that Edison and not Emile Berliner was the inventor of the carbon microphone. The carbon microphone was also used in radio broadcasting and public address work through the 1920s.

1896 Telephone (Sweden)

In the 1890s a new smaller style of telephone was introduced, the candlestick telephone, and it was packaged in three parts. The transmitter stood on a stand, known as a "candlestick" for its shape. When not in use, the receiver hung on a hook with a switch in it, known as a "switchhook." Previous telephones required the user to operate a separate switch to connect either the voice or the bell. With the new kind, the user was less likely to leave the phone "off the hook". In phones connected to magneto exchanges, the bell, induction coil, battery, and magneto were in a separate bell box called a " ringer box." In phones connected to common battery exchanges, the ringer box was installed under a desk, or other out of the way place, since it did not need a battery or magneto.

Cradle designs were also used at this time, with a handle with the receiver and transmitter attached, separate from the cradle base that housed the magneto crank and other parts. They were larger than the "candlestick" and more popular.

Disadvantages of single-wire operation, such as crosstalk and hum from nearby AC power wires, had already led to the use of twisted pairs and, for long-distance telephones, four-wire circuits. Users at the beginning of the 20th century did not place long-distance calls from their own telephones but made an appointment to use a special sound-proofed long-distance telephone booth furnished with the latest technology.

Around 1893, the country leading the world in telephones per 100 persons-known as teledensity-was Sweden with 0.55 in the whole country but 4 in Stockholm (10,000 out of a total of 27,658 subscribers).[30] This compares with 0.4 in the US for that year.[31] Telephone service in Sweden developed through a variety of institutional forms: the International Bell Telephone Company (a U.S. multinational), town and village co-operatives, the General Telephone Company of Stockholm (a Swedish private company), and the Swedish Telegraph Department (part of the Swedish government). Since Stockholm consists of islands, telephone service offered relatively large advantages, but had to use submarine cables extensively. Competition between Bell Telephone and General Telephone, and later between General Telephone and the Swedish Telegraph Dept., was intense.

In 1893, the U.S. was considerably behind Sweden, New Zealand, Switzerland, and Norway in teledensity. The U.S. became the world leadership in teledensity with the rise of many independent telephone companies after the Bell patents expired in 1893 and 1894.

A German rotary dial telephone, the W48

By 1904, over three million phones in the U.S.[32] were connected by manual switchboard exchanges. By 1914, the U.S. was the world leader in telephone density and had more than twice the teledensity of Sweden, New Zealand, Switzerland, and Norway. The relatively good performance of the U.S. occurred despite competing telephone networks not interconnecting.[33] On January 7, 1927, W. S. Gifford, president of the American Telephone & Telegraph Company, called Evelyn P. Murray to test the first commercial telephone line across the Atlantic Ocean.[29]

What turned out to be the most popular and longest-lasting physical style of telephone was introduced in the early 20th century, including Bell's model 102 telephone. A carbon granule transmitter and electromagnetic receiver were united in a single molded plastic handle, which when not in use were placed in a cradle in the base unit. The circuit diagram[34] of the model 102 shows the direct connection of the receiver to the line, while the transmitter was induction coupled, with energy supplied by a local battery. The coupling transformer, battery, and ringer were in a separate enclosure from the desk set. The rotary dial in the base interrupted the line current by repeatedly but very briefly disconnecting the line 1 to 10 times for each digit, and the hook switch (in the center of the circuit diagram) permanently disconnected the line and the transmitter battery while the handset was on the cradle.

Starting in the 1930s, the base of the telephone also enclosed its bell and induction coil, obviating the need for a separate ringer box. Power was supplied to each subscriber line by central-office batteries instead of the user's local battery, which required periodic service. For the next half century, the network behind the telephone grew progressively larger and much more efficient, and, after the rotary dial was added, the instrument itself changed little until Touch-Tone signaling started replacing the rotary dial in the 1960s.

The history of mobile phones can be traced back to two-way radios permanently installed in vehicles such as taxicabs, police cruisers, railroad trains, and the like. Later versions such as the so-called transportables or "bag phones" were equipped with a cigarette-lighter plug so that they could also be carried, and thus could be used as either mobile two-way radios or as portable phones by being patched into the telephone network.

In December 1947, Bell Labs engineers Douglas H. Ring and W. Rae Young proposed hexagonal cell transmissions for mobile phones.[35] Philip T. Porter, also of Bell Labs, proposed that the cell towers be at the corners of the hexagons rather than the centers and have directional antennas that would transmit/receive in 3 directions (see picture at right) into 3 adjacent hexagon cells.[36][37] The technology did not exist then and the radio frequencies had not yet been allocated. Cellular technology was undeveloped until the 1960s, when Richard H. Frenkiel and Joel S. Engel of Bell Labs developed the electronics.

Meanwhile, the 1956 inauguration of the TAT-1 cable and later international direct dialing were important steps in putting together the various continental telephone networks into a global network.

On 3 April 1973, Motorola manager Martin Cooper placed a cellular-phone call (in front of reporters) to Dr. Joel S. Engel, head of research at AT&T's Bell Labs. This began the era of the handheld cellular-mobile phone.

Cable-television companies began to use their fast-developing cable networks with ducting under the streets of the United Kingdom in the late 1980s to provide telephony services in association with major telephone companies. One of the early cable operators in the UK, Cable London, connected its first cable telephone customer in about 1990.

Digital telephone technology edit

The rapid development and wide adoption of pulse-code modulation (PCM) digital telephony was enabled by metal-oxide-semiconductor (MOS) technology.[38] The MOS field-effect transistor (MOSFET) was invented by Mohamed M. Atalla and Dawon Kahng at Bell Telephone Laboratories in 1959, and the MOS integrated circuit (MOS IC) chip was proposed soon after, but MOS technology was initially overlooked by Bell because they did not find it practical for analog telephone applications, before it was commercialized by Fairchild and RCA for digital electronics such as computers.[39][38] MOS technology eventually became practical for telephone applications with the MOS mixed-signal integrated circuit, which combines analog and digital signal processing on a single chip, developed by former Bell engineer David A. Hodges with Paul R. Gray at UC Berkeley in the early 1970s.[38] In 1974, Hodges and Gray worked with R.E. Suarez to develop MOS switched capacitor (SC) circuit technology, which they used to develop the digital-to-analog converter (DAC) chip, using MOSFETs and MOS capacitors for data conversion. This was followed by the analog-to-digital converter (ADC) chip, developed by Gray and J. McCreary in 1975.[38]

MOS SC circuits led to the development of PCM codec-filter chips in the late 1970s.[38][40] The silicon-gate CMOS (complementary MOS) PCM codec-filter chip, developed by Hodges and W.C. Black in 1980,[38] has since been the industry standard for digital telephony.[38][40] By the 1990s, telecommunication networks such as the public switched telephone network (PSTN) had been largely digitized with very-large-scale integration (VLSI) CMOS PCM codec-filters, widely used in switching systems for telephone exchanges, private branch exchanges (PBX) and key telephone systems (KTS); user-end modems; data transmission applications such as digital loop carriers, pair gain multiplexers, telephone loop extenders, integrated services digital network (ISDN) terminals, digital cordless telephones and digital cell phones; and applications such as speech recognition equipment, voice data storage, voice mail and digital tapeless answering machines.[40] The bandwidth of digital telecommunication networks has been rapidly increasing at an exponential rate, as observed by Edholm's law,[41] largely driven by the rapid scaling and miniaturization of MOS technology.[42][38]

The British companies Pye TMC, Marconi-Elliott and GEC developed the digital push-button telephone, based on MOS IC technology, in 1970. It was variously called the "MOS telephone", the "push-button telephone chip", and the "telephone on a chip". It used MOS IC logic, with thousands of MOSFETs on a chip, to convert the keypad input into a pulse signal. This made it possible for push-button telephones to be used with pulse dialing at most telephone exchanges.[43][44] MOS telephone technology introduced a new feature: the use of MOS memory chips to store phone numbers, which could then be used for speed dialing at the push of a button.[43][44][45] This was demonstrated in the United Kingdom by Pye TMC, Marcno-Elliot and GEC in 1970.[43][44] Between 1971 and 1973, Bell combined MOS technology with touch-tone technology to develop a push-button MOS touch-tone phone called the "Touch-O-Matic" telephone, which could store up to 32 phone numbers. This was made possible by the low cost, low power requirements, small size and high reliability of MOSFETs, over 15,000 of which were contained on ten MOS IC chips, including one chip for logic, one for the keypad dial interface, and eight for memory.[46]

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This history of the telephone chronicles the development of the electrical telephone, and includes a brief overview of its predecessors. The first telephone patent was granted to Alexander Graham Bell in 1869. Before the invention of electromagnetic telephones, mechanical acoustic devices existed for transmitting speech and music over a greater distance.

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The man's "pancake kidney" is visible between the two arrows in this CT scan, sitting just above the bladder (the darker blue circular structure). Normally, the two separate kidneys would sit higher up in the body, closer to the top two vertebra (the white squares) that appear in the scan, and farther out to either side of the body.

Credit: BMJ Case Reports 2018

When an 18-year-old man in India went to the emergency room for intestinal problems, doctors ordered a computed tomography (CT) scan to get a clear look at the issue. But the scan revealed something completely unrelated to the man's gut problems: He had a rarely encountered condition called "pancake kidney," according to a recent report of his case.

The "extraordinarily rare" condition is almost exactly what it sounds like, said Dr. Steven Chang, an assistant professor of surgery in the division of urology at Brigham and Women's Hospital in Boston. Chang treats patients who have kidney cancer but was not involved in the man's case.

A "pancake kidney" occurs when the top and bottom of the kidneys fuse together, so instead of two separate, kidney-bean-shaped organs, the person ends up with one big, fused kidney, Chang told Live Science. [ 27 Oddest Medical Cases]

Of course, pancakes aren't the only flat, disc-like objects: The unconventional, fused organ may also be referred to as a "disc, doughnut, cake or a shield kidney," according to the case report, which was published online Oct. 2 in the journal BMJ Case Reports.

A pancake kidney forms during embryological development, Chang said. Normally, when the kidneys form, these two developing structures ascend to a location in the body that's closer to the mid-spine, with one kidney migrating to either side of the spine, he said.

But in a person who develops a pancake kidney, something goes awry during this ascent. The tops and bottoms of the two developing kidneys fuse, and a slight misdirection in the path of the kidney alters its body position, Chang said.

The pancake kidney can't get to a location in the body as high up as the mid-spine, Chang said. Instead the fused kidney settles into a lower position, located closer to the pelvis, Chang said. In the Indian man's case, his pancake kidney sat right above his bladder.

A pancake kidney isn't the only variety of kidney abnormality, however. A more common, but still rare, condition occurs when the two developing kidneys fuse together at the bottom - but not at the tops - creating a U-shape. This is known as a "horseshoe kidney," Chang said.

People can live their whole lives with a pancake kidney and never know they have it, Chang said.

Indeed, in the man's case, doctors weren't looking for a pancake kidney, and it wasn't causing any problems. (The reason that the man went to the hospital, an i ntestinal obstruction, was successfully treated, and wasn't related to his oddly shaped kidney.)

Still, a pancake kidney can cause some problems, Chang said. For example, a person with a pancake kidney may have recurring urinary tract infections or kidney stones. That's because the fused kidney may have trouble draining due to its location in the body and because other blood vessels and structures may be in the way, he noted.

But there's no need to treat a pancake kidney by surgically separating the mass into two kidneys, especially if a person has normal kidney function like this young man did, Chang said. This type of surgery would be difficult, and the risks would outweigh the benefits, he noted.

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This Man's 'Pancake' Kidney Looks Like It Sounds

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When an 18-year-old man in India went to the emergency room for intestinal problems, doctors ordered a computed tomography (CT) scan to get a clear look at the issue. But the scan revealed something completely unrelated to the man's gut problems: He had a rarely encountered condition called "pancake kidney," according to a recent report of his case.

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Credit: Shutterstock

SAN FRANCISCO - As scary as it may sound, a root canal is a fairly routine dental procedure. But for one 60-year-old man, the procedure turned life threatening when he developed meningitis, a swelling of the tissue surrounding his brain and spinal cord. Even more surprising, though, was that this dangerous outcome wasn't due to some ghastly slip of the dentist's drill or a germ-coated dental instrument. Indeed, the procedure went off without a hitch.

But several days after the procedure, the man arrived at an emergency room in New Jersey with a fever, headaches and neck pain. He informed doctors of his recent root canal and also mentioned that his dentist had instructed him to take amoxicillin - a common antibiotic - several days before the procedure.

Because of his symptoms, doctors suspected he had meningitis, which is almost always caused by an infection of some kind. So, they started him on antibiotics, but he only got worse. [ 27 Oddest Medical Cases]

That's when the doctors treating him suspected he might have drug-induced meningitis, or symptoms of meningitis that are triggered not by an infection, but by a specific drug. And in this case, the drug was amoxicillin.

Such a side effect is very rare, said Dr. Maria Nagori, an infectious-disease doctor at Geisinger Community Medical Center in Scranton, Pennsylvania, who treated the patient in 2017. "It's such an uncommon thing; I'd never heard of it before," said Nagori, who was completing a fellowship at Cooper University Hospital in Camden, New Jersey, at the time of the case.

Indeed, upon further research, Nagori found that only about a dozen cases of amoxicillin-induced meningitis had ever been reported.

Nagori presented the man's case report here on Oct. 4 at IDWeek, a meeting of several organizations focused on infectious diseases. The report has not yet been published in a peer-reviewed journal.

When tests for various infections came back negative, doctors stopped the man's antibiotic treatment, and he started getting better. At a follow-up visit, he was doing well, Nagori told Live Science.

After further questioning, doctors learned that the man had developed meningitis twice before: in 2011 and 2015. Each time, his meningitis symptoms occurred after he took amoxicillin before a dental procedure. But because the man had been treated at several different hospitals, and this is a rare side effect, no one made the connection with amoxicillin until his 2017 treatment.

What's more, the man didn't have any medical condition or risk factors that would have caused him to need antibiotics before a dental procedure like a root canal, Nagori said, meaning the antibiotics were unnecessary.

Nagori and colleagues advised the patient not to take amoxicillin again. Instead, he could take the antibiotic clindamycin.

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A Man Took Antibiotics Before Going to the Dentist. He Developed An Ultra-Rare Brain Side Effect

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SAN FRANCISCO - As scary as it may sound, a root canal is a fairly routine dental procedure. But for one 60-year-old man, the procedure turned life threatening when he developed meningitis, a swelling of the tissue surrounding his brain and spinal cord.

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The history of the elevator, if you define it as a platform that can move people and objects up and down, is actually a rather long one. Rudimentary elevators are known to have been in use in ancient Rome as far back as 336 B.C., with the first reference of one built by the talented Archimedes.

These early elevators were open cars rather than enclosed ones, and consisted of a platform with hoists that would enable the car to move vertically. The hoists were typically worked manually, either by people or animals, though sometimes water wheels were used. Romans continued to use these simple elevators for many years, usually to move water, building materials, or other heavy items from one place to another.

As for the dedicated passenger elevator, this was created in the 18th century, with one of the first used by King Louis XV in 1743. He had an elevator constructed at Versailles that would carry him from his apartments on the first floor to his mistress' apartments on the second floor. This elevator wasn't much more technologically advanced than those used in Rome. To make it work, men stationed in a chimney pulled on the ropes. They called it a "flying chair."

It wasn't until the 1800s that elevator technology really started to advance. For starters, elevators no longer needed to be worked manually. In 1823, two British architects-Burton and Hormer-built a steam-powered "ascending room" to take tourists up to a platform for a view of London. Several years later, their invention was expanded upon by architects Frost and Stutt who added a belt and counter-weight to the steam power.

Soon enough, hydraulic systems began to be created as well, using water pressure to raise and lower the elevator car. However, this wasn't practical in some cases-pits had to be dug below the elevator shaft to enable the piston to pull back. The higher the elevator went, the deeper the pit had to be. Thus, this wasn't a viable option for taller buildings in big cities.

So despite the hydraulic systems being somewhat safer than steam-powered/cabled elevators, the steam powered ones with cables and counterweights, stuck around. They had just one major drawback: the cables could snap, and sometimes did, which sent the elevator plummeting to the bottom of the shaft, killing passengers and damaging building materials or other items being transported. Needless to say, no one was jumping to get on these dangerous elevators and so passenger elevators up to this point were largely a novelty.

The man who solved the elevator safety problem, making skyscrapers possible, was Elisha Otis, who is generally known as the inventor of the modern elevator. In 1852, Otis came up with a design that had a safety "brake." In the event that the cables broke, a wooden frame at the top of the elevator car would snap out and hit the walls of the shaft, stopping the elevator in its tracks.

Otis himself demonstrated the device, which he called a "safety hoist," at the New York World's Fair in 1854, when he went up in a make-shift elevator himself and had the ropes cut. Rather than plummeting to his death as the audience thought might happen, his safety hoist snapped out, catching the elevator within seconds. Needless to say, the crowd was impressed.

Otis went on to found his own elevator company, which installed the first public elevator in a New York building in 1874. The Otis Elevator Company is still known today as the world's largest elevator manufacturer.

While the cable elevator design has remained, many additional improvements have been made, the most obvious of which is that elevators now run on electricity rather than steam power, a change that came about starting in the 1880s. The electric elevator was patented by Alexander Miles in 1887, though one had been built by the German inventor Werner von Siemens in 1880.

Otis' safety hoist wasn't the end of safety innovation, either. These days, it's virtually impossible for an elevator to plummet and kill passengers. There are now multiple steel cables to hold the elevator's weight, plus a number of different braking systems to stop an elevator from falling if the cables somehow snap. If, despite all these safety measures, the elevator does fall, there are shock absorbers at the bottom of the shaft, making it unlikely death will occur and reducing the possibility of serious injury.

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Bonus Facts:

Elisha Otis is not considered to be the inventor of the modern elevator by everyone. Another man, Otis Tufts, patented an elevator design that had doors that opened and closed automatically and benches inside. However, Tufts' design did away with the typical cable system because of the safety issues, and instead used an impractical, expensive system of threading the elevator car up a giant screw. Obviously, this would be prohibitively expensive in tall buildings. Elisha Otis' design was much simpler (and closer to modern designs), easier to use, and less expensive to make, which is why he generally gets the credit and not Tufts. That said, the "Vertical Screw Railway" was installed in a few buildings in New York and Philadelphia.

The first elevator shaft was put in a building before Elisha Otis designed his safe, steam powered elevator. This was done in 1853 at the Cooper Union Foundation building in New York. Peter Cooper felt that elevators would be perfected and made safe at some point in the near future, so included it in the design of the building. It took a couple decades, but an elevator was eventually installed in the shaft by Elisha Otis' company.

Elisha Otis was born into a farming family in 1811, but he spent a lot of time at the blacksmith's as a child, fascinated by tools and making things. He created a number of inventions to help out around the farm, including a pulley and lift system. At one point, he also worked in a bed-making factory and built a machine that increased production rates significantly.

Otis' daring elevator safety demonstration at the World Fair was hyped up by Phineas Barnum, who is also responsible for making phrases like "jump on the bandwagon" popular.

Otis Tufts also invented the steam-powered printing press and steam-powered pile driver.

Emily Upton writes for the wildly popular interesting fact website TodayIFoundOut.com. To subscribe to Today I Found Out's "Daily Knowledge" newsletter, click here or like them on Facebook here. You can also check 'em out on YouTube here. has been republished with permission from TodayIFoundOut.com.

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The history of the elevator, if you define it as a platform that can move people and objects up and down, is actually a rather long one. Rudimentary elevators are known to have been in use in ancient Rome as far back as 336 B.C., with the first reference of one built by the talented Archimedes.

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#5 - A newly developed light bulb is much more - LSAT Discussion Forum