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Sleep-deprived mice find 🤬 more rewarding

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Sleep-deprived mice find 🤬 more rewarding

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I thought this article was very... interesting to say the least. At first i was just thinking why??? But then i realised that this also applies to humans

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Sleep deprivation may pave the way to cocaine addiction. Too-little sleep can increase the rewarding properties of cocaine, according to new research in mice published in eNeuro.

Poor sleep and cocaine use go hand-in-hand. Both acute and chronic cocaine use disrupts sleep, and sleep disturbances can increase the likelihood of relapse. But it's unclear how sleep deprivation contributes to cocaine addiction. The orexin system, which influences motivated and addictive behaviors through the peptide orexin, may underly the relationship: orexin activity increases during sleep deprivation, and blocking orexin receptors reduces reward-seeking.

Bjorness and Greene conditioned mice to associate a room with cocaine and examined how sleep deprivation affected their ability to develop a preference for the cocaine room. Sleep-deprived mice formed a preference for a lower dose of cocaine, one that did not affect rested mice. They also formed a stronger preference for a standard cocaine dose, indicating an increase in the amount of reward cocaine provided. Blocking the orexin system reduced the increased cocaine preference driven by sleep deprivation.

Journal Reference:

Theresa E. Bjorness, Robert W. Greene. Sleep deprivation enhances conditioned place preference in an orexin receptor modulated manner. eneuro, 2020; ENEURO.0283-20.2020 DOI: 10.1523/ENEURO.0283-20.2020

Cite This Page:

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insomnia; cocaine; sleep disorders; obstructive sleep apnea; illegal drugs; addiction; parenting; disorders and syndromes

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Sleep-deprived mice find cocaine more rewarding: Sleep deprivation increases rewarding properties of cocaine through motivation peptide

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Sleep deprivation may pave the way to cocaine addiction. Too-little sleep can increase the rewarding properties of cocaine, according to new research in mice published in eNeuro. Poor sleep and cocaine use go hand-in-hand. Both acute and chronic cocaine use disrupts sleep, and sleep disturbances can increase the likelihood of relapse.

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I found this article intriguing as it discusses how human fingerprints have a self-regulating moisture mechanism that not only helps us to avoid dropping things, but could help scientists to create better prosthetic limbs, robotic equipment and virtual reality environments. A new study has revealed that Primates(Humans, apes etc.) have evolved epidermal ridges on their hands and feet with a higher density of sweat glands than elsewhere on their bodies. This allows precise regulation of skin moisture to give greater levels of grip when manipulating objects.

Questions:
1.x

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Human fingerprints have a self-regulating moisture mechanism that not only helps us to avoid dropping our smartphone, but could help scientists to develop better prosthetic limbs, robotic equipment and virtual reality environments, a new study reveals.

Primates -- including humans, monkeys and apes -- have evolved epidermal ridges on their hands and feet with a higher density of sweat glands than elsewhere on their bodies. This allows precise regulation of skin moisture to give greater levels of grip when manipulating objects.

Fingerprints help to increase friction when in contact with smooth surfaces, boost grip on rough surfaces and enhance tactile sensitivity. Their moisture-regulating mechanism ensures the best possible hydration of the skin's keratin layer to maximise friction.

Researchers at the University of Birmingham worked with partners at research institutions in South Korea, including Seoul National University and Yonsei University -- publishing their findings today in Proceedings of the National Academy of Sciences (PNAS).

Co-author Mike Adams, Professor in Product Engineering and Manufacturing, at the University of Birmingham commented: "Primates have evolved epidermal ridges on their hands and feet. During contact with solid objects, fingerprint ridges are important for grip and precision manipulation. They regulate moisture levels from external sources or the sweat pores so that friction is maximised and we avoid 'catastrophic' slip and keep hold of that smartphone."

"Understanding the influence of finger pad friction will help us to develop more realistic tactile sensors -- for example, applications in robotics and prosthetics and haptic feedback systems for touch screens and virtual reality environments."

Ultrasonic lubrication is commonly used in touch screen displays that provide sensory 'haptic' feedback, but its effectiveness is reduced when a user has dry compared with moist finger pads. Moreover, being able to distinguish between fine-textured surfaces, such as textiles, by touch relies on the induced lateral vibrations but the absence of sliding friction inhibits our ability to identify what we are actually touching.

Fingerprints are unique to primates and koalas -- appearing to have the dual function of enhancing evaporation of excess moisture whist providing a reservoir of moisture at their bases that enables grip to be maximised.

The researchers have discovered that, when finger pads are in contact with impermeable surfaces, the sweat from pores in the ridges makes the skin softer and thus dramatically increases friction. However, the resulting increase in the compliance of the ridges causes the sweat pores eventually to become blocked and hence prevents excessive moisture that would reduce our ability to grip objects.

Using hi-tech laser-based imaging technology, the scientists found that moisture regulation could be explained by the combination of this sweat pore blocking and the accelerated evaporation of excessive moisture from external wetting as a result of the specific cross-sectional shape of the epidermal furrows when in contact with an object.

These two functions result in maintaining the optimum amount of moisture in the fingerprint ridges that maximises friction whether the finger pad is initially wet or dry.

"This dual-mechanism for managing moisture has provided primates with an evolutionary advantage in dry and wet conditions -- giving them manipulative and locomotive abilities not available to other animals, such as bears and big cats," added Professor Adams.

Journal Reference:

Seoung-Mok Yum, In-Keun Baek, Dongpyo Hong, Juhan Kim, Kyunghoon Jung, Seontae Kim, Kihoon Eom, Jeongmin Jang, Seonmyeong Kim, Matlabjon Sattorov, Min-Geol Lee, Sungwan Kim, Michael J. Adams, Gun-Sik Park. Fingerprint ridges allow primates to regulate grip. Proceedings of the National Academy of Sciences, 2020; 202001055 DOI: 10.1073/pnas.2001055117

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eye care; psoriasis; alternative medicine; monkeys; animal learning and intelligence; apes; thermodynamics; biometric; engineering

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Human fingerprints have a self-regulating moisture mechanism that not only helps us to avoid dropping our smartphone, but could help scientists to develop better prosthetic limbs, robotic equipment and virtual reality environments, a new study reveals.

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Scientists invent technology to extract oxygen and fuel from Mars’ salty water in huge step forward to colonising Red Planet

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Scientists invent technology to extract oxygen and fuel from Mars’ salty water in huge step forward to colonising Red Planet

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This article dictates the advancements in electrolysis that will further advance the ability to put humans on Mars.

I've found this article interesting as it exposes the fundamentals in how humans on Mars, whether they be living there permanently or temporarily, will be able to thrive and survive. It hints at the possibility of a 'Star Trek' like future where Mars may even become its own independent state. The topic is still very much in its infancy, however I expect great advancements in the field soon.

Questions
1. How long would it take for this technology to be refined enough to be taken to Mars itself for experimentation and implementation?

2. Could this newfound technology have negative impacts that have not been found yet? And how devastating may these impacts be

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Humankind's quest to set up base on Mars has received a boost as scientists have now claimed to have discovered a way that can help extract oxygen and fuel from the salty water found on the red planet.

The water which is salty due to the Martian soil can't be used for drinking purposes. Even electrolysis, the usual method of using electricity to break it down into oxygen (to breathe) and hydrogen (for fuel) requires removing the salt - a cumbersome method that can be a costly endeavour in a harsh environment like Mars.

But now researchers at Washington University in St Louis have developed an electrolysis system that can directly separate oxygen and hydrogen from briny water - in a less complicated and expensive manner.

They examined their system in a simulated Martian atmosphere where the temperature was about -36C, in addition to testing it under typical terrestrial conditions.

"Our Martian brine electrolyser radically changes the logistical calculus of missions to Mars and beyond. This technology is equally useful on Earth where it opens up the oceans as a viable oxygen and fuel source," said Vijay Ramani of Washington University.

In the summer of 2008, NASA's Phoenix Mars Lander "touched and tasted" Martian water, vapors from melted ice dug up by the lander. Since then, the European Space Agency's Mars Express has discovered several underground ponds of water which remain in a liquid state thanks to the presence of magnesium perchlorate - salt.

For instance, for living on Mars and returning to Earth, astronauts would need to manufacture some of the necessities, including water and fuel and this research could be very useful for such a purpose.

In years ahead, space agencies - both private and public - aim to send manned missions to Mars and even try to live there temporarily.

Space exploration company SpaceX's founder and chief executive officer Elon Musk on Tuesday said he expected humans to land on Mars in six years. He also said that SpaceX plans to launch an unmanned spacecraft and land on Mars in two years, with a chance of the first human landing on Mars in four years instead of six.

United States' space agency Nasa's Perseverance rover which was launched in July 2020 is scheduled to land at Jezero Crater on Mars on 18 February 2021. It will look at signs of ancient life and collect rock and soil samples for a possible return to Earth.

It is carrying instruments that will use high-temperature electrolysis but the Mars Oxygen In-Situ Resource Utilization Experiment (MOXIE) will be producing oxygen only, from the carbon dioxide in the air.

Mars rover Curiosity finds evidence of ancient fast-moving streams on surface of red planet
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Mars rover Curiosity finds evidence of ancient fast-moving streams on surface of red planet

Mars rover Curiosity finds evidence of ancient fast-moving streams on surface of red planet

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Mars rover Curiosity finds evidence of ancient fast-moving streams on surface of red planet

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AP

However, this latest research claims that by the system developed in Mr Ramani's lab can produce 25 times more oxygen than MOXIE using the same amount of power and can also produce hydrogen that can be used to fuel the return trip.

Several underground ponds of water on Mars have earlier been discovered which remain in a liquid state thanks to the presence of magnesium perchlorate.

Shrihari Sankarasubramanian, a research scientist and joint first author of the paper, said: "Paradoxically, the dissolved perchlorate in the water, so-called impurities, actually help in an environment like that of Mars.

"They prevent the water from freezing ... and also improve the performance of the electrolyser system by lowering the electrical resistance."

The researchers intend to use it on Earth as well. They believe it could be useful in defense, creating oxygen on demand in submarines and could also provide oxygen during deep sea exploration.

The research was published in the journal Proceedings of the National Academy of Sciences.

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Scientists invent technology that can extract oxygen and fuel from Mars' salty water in huge step forward to colonising Red Planet

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Humankind's quest to set up base on Mars has received a boost as scientists have now claimed to have discovered a way that can help extract oxygen and fuel from the salty water found on the red planet. The water which is salty due to the Martian soil can't be used for drinking purposes.

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Planets with many neighbours may be the best places to look for life

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Planets with many neighbours may be the best places to look for life

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This article discusses how it is more likely for life to exist on a planet that has multiple sibling planets, than ones that do not. Systems with a number of planets have much rounder orbits than those with just one, indicating a "calmer family history". According to Uffe Gråe,  a long-lasting profusion of sibling planets may be one of the reasons why life on Earth became possible. This means that life is more promising on planets amongst other surrounding planets, since they have depended on them for billions of years to be protected and to survive. This article interests me as I find it very fascinating how the process for life to be possible on Earth has taken billions of years. The possibility that other planets have also undergone this long process of maintaining life blows my mind.

Questions:
1. What other characteristics are required for planets to have life on them?
2. Are there any specific planets with neighbours in the universe that are suspected to have life?

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If you're looking for life beyond the solar system, there's strength in numbers.

A new study suggests that systems with multiple planets tend to have rounder orbits than those with just one, indicating a calmer family history. Only child systems and planets with more erratic paths hint at past planetary sibling clashes violent enough to knock orbits askew, or even lead to banishment. A long-lasting abundance of sibling planets might therefore have protected Earth from destructive chaos, and may be part of what made life on Earth possible, says astronomer Uffe Gråe Jørgensen of the Niels Bohr Institute in Copenhagen.

"Is there something other than the Earth's size and position around the star that is necessary in order for life to develop?" Jørgensen says. "Is it required that there are many planets?"

Most of the 4,000-plus exoplanets discovered to date have elongated, or eccentric, orbits. That marks a striking difference from the neat, circular orbits of the planets in our solar system. Rather than being an oddity, those round orbits are actually perfectly normal - for a system with so many planets packed together, Jørgensen and his Niels Bohr colleague Nanna Bach-Møller report in a paper published online October 30 in the Monthly Notices of the Royal Astronomical Society.

Bach-Møller and Jørgensen analyzed the eccentric paths of 1,171 exoplanets orbiting 895 different stars. The duo found a tight correlation between number of planets and orbit shape. The more planets a system has, the more circular their orbits, no matter where you look or what kind of star they orbit.

Earlier, smaller studies also saw a correlation between number of planets and orbit shapes, says astrophysicist Diego Turrini of the Italian National Astrophysics Institute in Rome. Those earlier studies used only a few hundred planets.

"This is a very important confirmation," Turrini says. "It is providing us an idea of ... how likely it is there will be no fight in the family, no destructive events, and your planetary system will remain as it formed ... long enough to produce life."

Systems with as many planets as ours are exceedingly rare, though. Only one known system comes close: the TRAPPIST-1 system, with seven roughly Earth-sized worlds ( SN: 2/22/17). Astronomers have found no solar systems so far, other than ours, with eight or more planets. Extrapolating out to the number of stars expected to have planets in the galaxy, Jørgensen estimates that about 1 percent of planetary systems have as many planets as we do.

"It's not unique, but the solar system belongs to a rare type of planetary system," he says.

That could help explain why life seems to be rare in the galaxy, Jørgensen suggests. Exoplanet studies indicate that there are billions of worlds the same size as Earth, whose orbits would make them good places for liquid water. But just being in the so-called "habitable zone" is not enough to make a planet habitable ( SN: 10/4/19).

"If there are so many planets where we could in principle live, why are we not teeming with UFOs all the time?" Jørgensen says. "Why do we not get into traffic jams with UFOs?"

The answer might lie in the different histories of planetary systems with eccentric and circular orbits. Theories of solar system formation predict that most planets are born in a disk of gas and dust that encircles a young star. That means young planets should have circular orbits, and all orbit in the same plane as the disk.

"You want the planets to not come too close to each other, otherwise their interactions might destabilize the system," says Torrini. "The more planets you have the more delicate the equilibrium is."

Planets that end up on elliptical orbits may have gotten there via violent encounters with neighboring planets, whether direct collisions that break both planets apart or near-misses that toss the planets about ( SN: 2/27/15). Some of those encounters may have ejected planets from their solar systems altogether, possibly explaining why planets with eccentric orbits have fewer siblings ( SN: 3/20/15).

Earth's survival may therefore have depended on its neighbors playing nice for billions of years ( SN: 5/25/05). It doesn't need to have escaped violence altogether, either, Jørgensen says. One popular theory holds that Jupiter and Saturn shifted in their orbits billions of years ago, a reshuffling that knocked the orbits of distant comets askew and send them careening into the inner solar system. Several lines of evidence suggest comets could have brought water to the early Earth ( SN: 5/6/15).

"It's not the Earth that is important," Jørgensen says. "It's the whole configuration of the planetary system that's important for life to originate on an earthlike planet."

Questions or comments on this article? E-mail us at feedback@sciencenews.org

Lisa Grossman is the astronomy writer. She has a degree in astronomy from Cornell University and a graduate certificate in science writing from University of California, Santa Cruz. She lives near Boston.

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Planets with many neighbors may be the best places to look for life

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If you're looking for life beyond the solar system, there's strength in numbers. A new study suggests that systems with multiple planets tend to have rounder orbits than those with just one, indicating a calmer family history. Only child systems and planets with more erratic paths hint at past planetary sibling clashes violent enough to knock orbits askew, or even lead to banishment.

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🤬 may help treat depression, a small study finds

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🤬 may help treat depression, a small study finds

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https://www.sciencenews.org/article/🤬-treat-depression-mushrooms-psychedelic

I find this study interesting, because the use of psychedelics in medicine (as opposed to traditional recreational use) is a growing field. Additionally, it's a controversial topic that certainly needs to have larger scale studies done to produce credible results. The topic is extremely intriguing, through the study is flawed, due to the small number of participants and lack of racial diversity.

QUESTIONS
1. How will all ethnicities react to 🤬 as a treatment for depression? Will particular ethnicities posses any intolerances (as many East Asians experience with alcohol)?

2. Recreational drugs are a controversial topic and can have ethical and religious dilemmas. If this topic is further researched will the negative connotations be removed?

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Gene drive wiped out a population of mosquitoes:

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Gene drive wiped out a population of mosquitoes:

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https://www.sciencenews.org/article/lab-tests-gene-drive-wiped-out-population-mosquitoes

This study caught my eye because it proves to us that altering so much as even a single gene can result in the eradication of populations of parasites. In this case, it (the inserted gene) physically prevents female mosquitoes from laying eggs, thus preventing a "next-to-subsequent" generation of mosquitoes from arising.

Questions:

1. Can the transcription of the heriditary structural genes of the tapeworm Taenia saginata, which code for the proteins that form the suckers and hooks of the creature be inhibited by a gene drive with a regulatory function
(i.e., it codes for transcription factors that prevent the transcription of the targeted structural genes)

OR

Can the heriditary structural genes themselves be modified in such a manner that the mutated genes produce proteins that form weak/defective  hooks or suckers that in turn prevent the attaching of the tapeworm to the walls of the intestine as a result of which it is unable to parasitize or lay eggs.

[I assume this "defect" can arise as a result of even a single point mutation as is the case in sickle haemoglobin where codon GAG (codes for Gly) is mutated into GUG (which codes for Val) and as a result of this single change in ONLY ONE out of the total 287 amino acids that make up the protein, the shape of the red blood cell changes from an elliptical shape to a distorted, asymmetrical "sickle like" shape. As a result of this deformation, the affected red blood cell doesn't function properly.]

2. TBC

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The first known particle with four of the same kind of heavy Quark

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The first known particle with four of the same kind of heavy Quark

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https://www.sciencenews.org/article/new-particle-cern-tetraquark-first-four-same-kind-quark

forces and strong interactions.The article is based on an already on going experiments and further extensive researching o expand the horizons of particle physics.

A major breakthrough occurred in particle physics when a particle was found to be constructed by 4 of the same kind of quarks. while all the previous known particle are composed of 3 quarks.

the discovery of this particle could lead to developing a clearer understanding of forces which bind these quarks, hence contribute to strong interactions in particle physics.

Q1. what properties of the individual quarks would have to be relayed upon to create a particle with four quarks?

Q2. how would investigating a four heavy quark particle help scientist relate this to fundamental forces and strong interactions?

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I found this article to be interesting as it takes a closer look at the biological advancements of earths much more smaller eco-systems. Tiny life on our planet has such a huge impact on giant life, this is why I have always taken an interest towards smaller life forms.

To see how protective the armour is, the researchers tested the hardness of the ant exoskeleton by poking armored and nonarmored pieces until an indentation formed. Despite being a mere 7 percent of the overall thickness of the exoskeleton, the calcite coating at least doubles the exoskeleton’s hardness, the team found.

It’s unclear how the armour is made, though Currie thinks bacteria are involved. If so, this could be another way the ants’ microbiome makes a huge difference to the insects’ survival.

My Questions:
Can these natural forming mineral armours be used on other insects in order to decrease the population of leaf-cutting insects?

Does the increase of population of leaf-cutting insects, as a result of this natural forming armour, pose a threat to farming?

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Leaf-cutting worker ants might look like they'd be helpless against an enemy soldier ant many times their size. But some of the smaller ants have a secret: Their entire body is coated with a thin but tough layer of mineral armor.

It's the first time that this type of external, whole-body mineralization has been found in an adult insect, researchers report online November 24 in Nature Communications.

"I found rock ants," evolutionary biologist Hongjie Li recalls telling his colleague, evolutionary biologist Cameron Currie, when the first experimental results of the hard coating came in. "I can still feel the excitement now," Li says.

The discovery was serendipitous, says Currie, of the University of Wisconsin-Madison, who has been studying leaf-cutting ants for more than 20 years. His lab had been examining interactions between ants and their external microbes, which are thought to play a pivotal role in the ants' farming practices ( SN: 4/23/20), when the team encountered a white sheen on the exoskeletons of Acromyrmex echinatior worker ants.

That coating needed to come off so the researchers could examine the structure of the exoskeleton in greater detail. So Currie tasked Li, then a postdoctoral student in Currie's lab who's now at Ningbo University in China, with removing it. But nothing seemed to work, suggesting the coating wasn't a wax or other carbon-based compound. Then, while brushing his teeth, Li had an epiphany: mouthwash. It helps remove all sorts of food residue without harming the tongue, and can dissolve mineral deposits on teeth, so Li decided to give the liquid a try.

The mouthwash did the trick, and also gave the team its first clue that the coating was mineral in nature. Further chemical, X-ray and microscopic examinations revealed a thin layer of calcite containing high levels of magnesium.

To see how protective the armor is, the researchers tested the hardness of the ant exoskeleton by poking armored and nonarmored pieces until an indentation formed. Despite being a mere 7 percent of the overall thickness of the exoskeleton, the calcite coating at least doubles the exoskeleton's hardness, the team found.

The discovery is surprising, says Duncan Murdock, a paleobiologist at the Oxford University Museum of Natural History, though perhaps not wholly unexpected, he adds. That's because ants are distant cousins of crabs and other crustaceans, which generally have mineralized exoskeletons.

It's unclear how the armor is made, though Currie thinks bacteria are involved. If so, this could be another way the ants' microbiome makes a huge difference to the insects' survival.

The team also tested how well the armor protected the ants in fights with other, bigger ant species. In staged battles between a trio of workers and a solitary soldier ant from a different species, Atta cephalotes, this mineral armor singlehandedly tipped the scale in the workers' favor, the researchers say. Nearly all the ants that were raised not to produce armor were killed by the soldier ant, while the vast majority of the armored ants survived.

From left: Caitlin M. Carlson; H. Li et al/Nature Communications 2020

Robert Schofield, a biophysicist at the University of Oregon in Eugene, isn't convinced by the battle data, and wonders whether the armorless ants had other differences that may have led to their demise. Still, he's intrigued, and plans to investigate similar coatings he's seen on other leaf-cutting ants.

Currie plans to examine other ants as well, in the hopes of determining how widespread the armor phenomenon is. Figuring out how the thin but tough coating forms, he says, could one day prove useful to people in developing protective coatings for all kind of products.

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Mineral body armor helps some leaf-cutting ants win fights with bigger kin

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Leaf-cutting worker ants might look like they'd be helpless against an enemy soldier ant many times their size. But some of the smaller ants have a secret: Their entire body is coated with a thin but tough layer of mineral armor.

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This rare bird is male on one side and female on the other

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This rare bird is male on one side and female on the other

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https://www.sciencenews.org/article/bird-male-female-grosbeak-gynandromorph

I found this article interesting as it explores the findings of a strange bird that is a half-male, half-female creature known as a gynandromorph. Researchers state this bird is likely the result of an unusual event when two sperm fertilize an egg that has two nuclei instead of one. This means that the egg can then develop male 🤬 chromosomes on one side and female 🤬 chromosomes on the other, ultimately leading to a bird with a testis and other male characteristics on one half of its body and an ovary and other female qualities on the other half.

1. Can these types of creatures reproduce?
2. Are all of the somatic cells in gynandromorphs identical? For example if the organism were to undergo cloning, would the product have the same traits as the parent and also be gynandromorphs?

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Calories by the clock,Squeezing most of your calories in early doesn't impact weight loss

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Calories by the clock,Squeezing most of your calories in early doesn't impact weight loss

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Time-restricted eating, which restricts eating to specific hours of the day, did not impact weight among overweight adults with prediabetes or diabetes. Adults in the 12-week study ate the same healthy, pre-prepared foods, however, one group ate the bulk of their calories before 1 p.m. each day, versus the other group that ate 50% of their calories after 5 p.m.

1.does the caloric intake have an impact on the results ?

2: If it doesn't improve ones weight loss goals, why has it become a trend and well known method?

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Restricting meals to early in the day did not affect weight among overweight adults with prediabetes or diabetes, according to preliminary research to be presented at the American Heart Association's Scientific Sessions 2020. The meeting will be held virtually, Friday, November 13 -- Tuesday, November 17, 2020.

"We have wondered for a long time if when one eats during the day affects the way the body uses and stores energy," said study author Nisa M. Maruthur, M.D., M.H.S., associate professor of medicine, epidemiology and nursing at Johns Hopkins University in Baltimore. "Most prior studies have not controlled the number of calories, so it wasn't clear if people who ate earlier just ate fewer calories. In this study, the only thing we changed was the time of day of eating."

Maruthur and colleagues followed 41 overweight adults in a 12-week study. Most participants (90%) were Black women with prediabetes or diabetes, and average age of 59 years. Twenty-one of the adults followed a time-restricted eating pattern, limiting eating to specific hours of the day and ate 80% of their calories before 1 p.m. The remaining 20 participants ate at usual times during a 12-hour window, consuming half of their daily calories after 5 p.m. for the entire 12 weeks. All participants consumed the same pre-prepared, healthy meals provided for the study. Weight and blood pressure were measured at the beginning of the study; then at 4 weeks, 8 weeks and 12 weeks.

The analysis found that people in both groups lost weight and had decreased blood pressure regardless of when they ate.

"We thought that the time-restricted group would lose more weight," Maruthur said. "Yet that didn't happen. We did not see any difference in weight loss for those who ate most of their calories earlier versus later in the day. We did not see any effects on blood pressure either."

The researchers are now collecting more detailed information on blood pressure recorded over 24 hours, and they will be compiling this information with the results of a study on the effects of time-restricted feeding on blood sugar, insulin and other hormones.

"Together, these findings will help us to more fully understand the effects of time-restricted eating on cardiometabolic health," Maruthur said.

Co-authors are Scott Pilla, M.D., M.H.S.; May T.T. Maw, M.B.B.S.M., M.P.H.; Daisy Duan, M.D.; Di Zhao, Ph.D.; Eliseo Guallar, M.D., Dr. P.H.; Ruth Alma Turkson Ocran, Ph.D.; Karen White, M.S.; Beiwen Wu, M.S.P.H.; Jeanne Charleston, R.N.; Lawrence J. Appel, M.D., M.P.H.; and Jeanne M. Clark, M.D., M.P.H.

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diet and weight loss; hypertension; fitness; obesity; heart disease; blood clots; anemia; diseases and conditions

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Calories by the clock? Squeezing most of your calories in early doesn't impact weight loss

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Time-restricted eating, which restricts eating to specific hours of the day, did not impact weight among overweight adults with prediabetes or diabetes. Adults in the 12-week study ate the same healthy, pre-prepared foods, however, one group ate the bulk of their calories before 1 p.m.

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This breakthrough in technology is interesting because it will change the way electronic information is processed as it is far more efficient due to the fact it mimics the structure of the human brain.

My two questions:

1. How are the chips so much more efficient solely due to the fact they mimic the structure of our brains?

2. How do you teach or force technology to work the same way the nervous system does?

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The ability of the human brain to process massive amounts of information while consuming minimal energy has long fascinated scientists. When there is a need, the brain dials up computation, but then it rapidly reverts to a baseline state. Within the realm of silicon-based computing, such efficiencies have never been possible. Processing large volumes of data requires massive amounts of electrical energy. Moreover, when artificial intelligence (AI) and its cousins deep learning and machine learning enter the picture, the problem grows exponentially worse.

Emerging neuromorphic chip designs may change all of this. The concept of a brain-like computing architecture, conceived in the late 1980s by California Institute of Technology professor Carver Mead, is suddenly taking shape. Neuromorphic frameworks incorporate radically different chip designs and algorithms to mimic the way the human brain works-while consuming only a fraction of the energy of today's microprocessors. The computing model takes direct aim at the inefficiencies of existing computing frameworks-namely the von Neumann bottleneck-which forces a processor to remain idle while it waits for data to move to and from memory and other components. This causes slow-downs and limits more advanced uses.

Figure. Intel combines 64 of its Loihi "brain-on-a-chip" neuromorphic chips to form a "Pohoiki Beach" neuromorphic system featuring eight million artificial neurons.

"Neuromorphic chips introduce a level of parallelism that doesn't exist in today's hardware, including GPUs and most AI accelerators," says Chris Eliasmith, a professor in the departments of Systems Design Engineering, and Philosophy, of the University of Waterloo in Ontario, Canada. Although today's deep learning systems rely on software to run basic neuromorphic systems using conventional field-programmable gate arrays (FPGA), central processing units (CPUs), and graphics processing units (GPUs), chips specifically designed to accomplish these tasks could revolutionize computing. Neuromorphic chips are packed with artificial neurons and artificial synapses that mimic the activity spikes that occur within the human brain-and they handle all this processing on the chip. This results in smarter, far more energy-efficient computing systems.

The impact of commercial neuromorphic computing could be enormous. The technology has repercussions across a wide swath of fields, including image and speech recognition, robotics and autonomous vehicles, sensors running in the Internet of Things (IoT), medical devices, and even artificial body parts.

As Adam Stieg, associate director of the California NanoSystems Institute at the University of California at Los Angeles (UCLA) puts it: "The ability to perform computation and learning on the device itself, combined with ultra-low energy consumption, could dramatically change the landscape of modern computing technology."

Modeling the Brain

The human brain is a remarkable product of evolution. It has a baseline energy footprint of about 20 watts, while processing complex tasks in milliseconds. While today's CPUs and GPUs can dramatically outperform the human brain for serial processing tasks, the process of moving data from memory to a processor and back not only creates latency, it expends enormous amounts of energy. A typical desktop computer burns through approximately 200 watts, while some supercomputers pull as much as 20 megawatts.

The value of neuromorphic systems is they perform on-chip processing asynchronously. Just as the human brain uses the specific neurons and synapses it needs to perform any given task at maximum efficiency, these chips use event-driven processing models to address complex computing problems. The resulting spiking neural network-so called because it encodes data in a temporal domain known as a "spike train"-differs from deep learning networks on GPUs. Existing deep learning methods rely on a more basic brain model for handling tasks, and they must be trained in a different way than neuromorphic chips.

"If we look at biology, we see incredible energy efficiency. This is something we're hoping to emulate in artificial systems," says Garrick Orchard, a researcher in Intel's Neuromorphic Computing Lab. The artificial neurons and synapses in neuromorphic chips can be stacked into layers and inserted in multiple cores. "The idea is that by taking inspiration from biology and by trying to better understand what principles are crucial for low-power computation, we can mimic these characteristics in silicon and push the boundaries of what's possible."

However, it isn't just slashing energy consumption that's appealing. Today's CPUs and GPUs-especially when they are used in autonomous vehicles and other independent systems-typically rely on external systems, primarily clouds, to handle some of the processing. The resulting latency is a problem for on-board systems that must make split-second decisions. "You can't collect a frame, pass it through to a deep neural net, and wait for the response when you're traveling down a freeway at 70 miles an hour," explains Abu Sebastian, Principal Research Staff Member at IBM Zurich. "Everything has to happen instantaneously, and that requires fast on-board processing."

So, while the need for clouds and edge networks won't disappear with neuromorphic chips, autonomous systems will be able to handle additional critical computing tasks on board. In areas such as image processing, this could produce exponential improvements. The latency gain of a spike-based neural network is a fundamental benefit-and it evolves beyond today's GPU systems. "Due to the asynchronous data-driven mode of computing, the salient information propagates in a fast manner through multiple layers of the network. The spikes begin to propagate immediately to higher layers once the lower layer provides sufficient activity. This is very different from conventional deep learning, where all layers have to be fully evaluated before the final output is obtained," Sebastian says.

Neuromorphic systems perform on-chip processing asynchronously, using event-driven processing models to address complex computing problems.

Neuromorphic chips also have the ability to learn continuously. "Because of their synaptic plasticity and the way they learn, they can continue to adapt and evolve," says Sebastian. In practical terms, for example, a robotic arm could learn to recognize different objects and pick them up and move them in a nuanced way. If a heavier grip is needed, the system would adjust accordingly, and if a lighter touch is required, it would also adapt. New items wouldn't throw a neuromorphic system off-kilter; it would simply "evolve" and "at a much faster rate than a CPU could," Orchard says.

By combining improved energy efficiency, reduced latency, and improved on-board learning, neuromorphic chips could push image recognition and speech processing to new levels of speed, efficiency, and accuracy. The technology could seed speech processing on virtually every type of device and produce new types of video cameras that operate at lower power and detect patterns and events more efficiently, Eliasmith says. Still another possible gain could take place in datacenters, which consume vast amounts of power and produce enormous carbon footprints.

The sum of these gains could produce revolutionary breakthroughs. Researchers have begun to explore the possibility of developing prosthetics that would give amputees the sensation of touch, brain-implanted chips that could aid stroke or Alzheimer's victims, self-healing electronic skin, and even vision sensors-essentially retinal implants-that could restore vision to the blind. Scientists also are exploring probabilistic neuromorphic systems that could predict the odds of an earthquake or recession with a high level of accuracy.

Says Eliasmith, "Neuromorphic designs allow scaling that hasn't been possible the past. We're able to go far beyond what today's systems can do."

Getting Smarter

Neuromorphic chips won't replace today's CPUs and GPUs; they are more likely to be embedded next to them as separate cores. This would expand the way we use existing digital technology-particularly on the edge of the network-and provide an accelerator for niche tasks. "Today's computers are very good at what they do. They will continue to outperform neuromorphic computing systems for conventional processing tasks. The technologies are complementary and so they will coexist," says G. Dan Hutcheson, CEO of VLSI Research, an independent market analysis and consulting firm that tracks the semiconductor industry.

Research and development efforts are beginning to produce tangible results. For instance, Intel Labs has developed Loihi, a research chip that uses a spiking neural network architecture. The processor contains 128 neuromorphic cores, three Lakemont (Intel Quark) CPU cores, and an off-chip communications network. The chip is designed with a high level of configurability, along with cores that can be optimized for specific tasks. This makes it appealing for specialized devices. More than 80 members of Intel's Neuromorphic Research Community-including universities, government labs, neuromorphic startup companies, and Fortune 500 firms, are now experimenting with Loihi.

IBM has developed a neuromorphic chip named TrueNorth. It has 4,096 cores, each with 256 neurons that, in turn, contain 256 synapses each. The microprocessor has 1/10,000th of the power density of a conventional von Neumann processor. It achieves this efficiency with a spiking neural network. Activity in the synthetic neurons occurs only when and where it is needed. This makes the chip particularly suited to high-speed and low-energy image processing and classification tasks. Although TrueNorth is an experimental chip, IBM is continuing to actively research neuromorphic technology, including approaches that focus on learning in the chip, Sebastian says.

More than 50 other AI startups around the world are actively developing neuromorphic chips and technology for a wide array of purposes, Hutcheson says. While all of this is taking place, others are developing software and systems to optimize chip performance. For instance, Eliasmith, who also heads a startup company called Applied Brain Research, develops algorithms and software used to program neuromorphic chips. This includes algorithms used for deep spiking networks, spiking and non-spiking adaptive controls, recurrent neural networks, on-chip learning, and spiking and non-spiking hierarchical reinforcement learning.

Neuromorphic technology remains in its infancy; there are no commercial products or killer applications. Yet the field is advancing rapidly and radically.

Meanwhile, in research labs, scientists are experimenting further with the technology. For example, at UCLA, Stieg and chemistry professor James Gimzewski have developed neuromorphic systems that can recognize rewards-similar to a rat in a maze-and artificial synapses that can "forget" by using varying input waves. Borrowing methods from human psychology, "We're building circuits that can adapt more efficiently by forgetting what isn't important," Gimzewski explains. The pair also have developed nano-wire technology that mimics millions of connections in the brain. "This introduces a level of impermanence that allows the devices to be far more flexible," says Stieg.

A New Model

For now, neuromorphic technology remains in its infancy. There are no commercial products, there are no killer applications. Yet, the field is advancing rapidly and radically. Commercially available chips should begin appearing within the next year or two, and the technology will likely take off in earnest within the next three to five years. Neuromorphic chips are likely to have a significant impact on edge devices and IoT systems that "must integrate dynamic and changing information that doesn't necessary run on a single algorithm-all while conserving energy," Stieg says.

"The world is not linear. It's not deterministic. It doesn't give definitive answers," he concludes. "Conventional von Neumann-based computing systems deal mostly with high-speed, predictable, deterministic processes. They perform these tasks well, but struggle when things become more complex. Neuromorphic computing aims to open up an entirely new and unexplored area of computing. It could allow us to do things with computers that we couldn't have imagined in the past."

Further Reading

Demis, E.C., Aguilera, R., Sillin, H.O., Scharnhorst, K., Sandouk, E.J., Aono, M., Stieg, A.Z., and Gimzewski, J. K.
Atomic Switch Networks - Nanoarchitectonic Design of a Complex System for Natural Computing. Nanotechnology, Volume 26, Number 20. April 27, 2015. https://iopscience.iop.org/article/10.1088/0957-4484/26/20/204003/meta

Davies, M., Srinivasa, N., Lin, T. Chinya, G., Cao, Y., Choday, S., Dimou, G., Joshi, P., Imam, N., Jain, S., Liao, Y. Lin, C., Lines, A., Liu, R., Mathaikutty, D., McCoy, S., Paul, A., Tse, J., Venkataramanan, G., Weng, Y., Wild, A., Yang, Y., and Wang, H.
Loihi: A Neuromorphic Manycore Processor with On-Chip Learning, IEEE Micro Volume: 38, Issue: 1, January/February 2018, pp. 82-99. https://ieeexplore.ieee.org/abstract/document/8259423

DeBole, M.V., Taba, B., Amir, A., Akopyan, F., Andreopoulos, A., Risk, W., Kusnitz, J., Otero, C.O., Nayak, T.K., Appuswamy, R., Carlson, P.J., Cassidy, A.S., Datta, P., Esser, S.K., Garreau, G.J., Holland, K.L., Lekuch, S., Mastro, M., McKinstry, J., di Nolfo, C., Paulovicks, B., Sawada, J., Schleupen, K., Shaw, B.G., Klamo, J.L., Flickner, M.D., Arthur, J.V., and Modha, D.S.
TrueNorth: Accelerating From Zero to 64 Million Neurons in 10 Years. Computer, Volume: 52, Issue: 5, May 2019, pp. 20-29. https://ieeexplore.ieee.org/abstract/document/8713821

Blouw., P., Choo, X., Hunsberger, E., and Eliasmith, C.
Benchmarking Keyword Spotting Efficiency on Neuromorphic Hardware. NICE '19: Proceedings of the 7th Annual Neuro-inspired Computational Elements Workshop March 2019 Article No.: 1 pp. 1-8. https://doi.org/10.1145/3320288.3320304

Author

Samuel Greengard is an author and journalist based in West Linn, OR, USA.
©2020 ACM 0001-0782/20/8
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The ability of the human brain to process massive amounts of information while consuming minimal energy has long fascinated scientists. When there is a need, the brain dials up computation, but then it rapidly reverts to a baseline state. Within the realm of silicon-based computing, such efficiencies have never been possible.

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Caribbean coral reefs under siege from aggressive algae

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Caribbean coral reefs under siege from aggressive algae

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https://www.sciencedaily.com/releases/2020/11/201130131412.htm

I found this article interesting as it highlights the fragile nature of marine ecosystems and how climate change can produce unexpected consequences that are still not completely understood by Scientists. The destructive Algae is "an ecological winner in our changing world", and it makes it "even harder for reef-systems to grow" in the Caribbean. This one example can be used to show the importance of getting on top of Global warming and climate change before it is too late.

1.  What consequential negative effects will be brought to other marine life in the area from the drastic shift in coral biodiversity?

2. What makes this certain species of Algae more effective in dominating an environmental scene other than other species?

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Prevention of sleep deprivation induced memory impairment and oxidative stress

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Prevention of sleep deprivation induced memory impairment and oxidative stress

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I found this interesting as it links to the ideas of trans humanism as well as is very applicable to a lot of people in a society that demands more and more of people's time as it allows more time to be used on things other than sleep and improvement of the human body.

1. How would using this as a medical application impact other bodily functions.
2. What would be the sociological changes caused by this

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Highlights

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Chronic sleep deprivation induced memory impairment.

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Cerebrolysin prevented this impairment.

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This was possibly achieved via normalizing antioxidant mechanisms changes in the hippocampus.

Abstract

Sleep plays a critical role in body health maintenance and well-being throughout a lifetime. Sleeplessness is the most prevalent feature in the modernist societies, which impairs memory. Studies have shown a strong correlation between sleep deprivation and memory impairment in humans and animals, which is related to oxidative stress induced damage within the brain. Cerebrolysin (CBL) is a neuropeptide that is used to treat vascular dementia. In this study, the effect of CBL on sleep-deprivation induced memory impairment was investigated. Sleep deprivation was induced in rats using the modified multiple platform model (8 h/day for 4 weeks). Concurrently, CBL was administered intraperitoneally for four weeks. Animal's performance (spatial learning and memory) was assessed using the radial arm water maze (RAWM). Additionally, oxidative stress biomarkers including reduced glutathione (GSH), oxidized Glutathione (GSSG), GSH/GSSG ratio, glutathione peroxidase (GPx), and catalase were assessed in the hippocampus. Current results showed that sleep deprivation impaired both short- and long- term memories ( P < 0.05), and that chronic CBL administration prevented such impairment. Additionally, CBL prevented decreases in hippocampal GPx, catalase, GSH and GSH/GSSG ratio and normalized increases in GSSG levels, which were impaired by the sleep deprivation model ( P < 0.05). In conclusion, result showed a protective effect for CBL administration against sleep-deprivation induced memory impairment, which could be related to CBL induced prevention of oxidative stress in the hippocampus.

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Cerebrolysin prevents sleep deprivation induced memory impairment and oxidative stress

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Chronic sleep deprivation induced memory impairment. * Cerebrolysin prevented this impairment. * This was possibly achieved via normalizing antioxidant mechanisms changes in the hippocampus. Sleep plays a critical role in body health maintenance and well-being throughout a lifetime. Sleeplessness is the most prevalent feature in the modernist societies, which impairs memory.

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Bacteriophages in Super-bug Bacteria and Cancer Cells

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Bacteriophages in Super-bug Bacteria and Cancer Cells

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http://www.clinicsinoncology.com/full-text/cio-v2-id1295.php

These two articles explain two different applications of bacteriophages. One is to use T4 phages to fight against super-bug bacteria and the other is to adopt this virus' unique features to deliver cancer drugs into target cells. Meanwhile, I learn about the history of bacteriophages being applied for a medical weapon. Now, as bacteriophages have been disregarded by scientists for a long time, now it is again attached importance, aiming to potentially cure superbug and deliver cancer drugs.

My two questions:
1. How to determine and improve the recognisability of phages to specific, targeted cancer cells or superbugs?
2. Because cancer cells are not bacteria, they may not be so easily recognised and attacked by phages. How can bacteriophages invade them by disguising cancer cells as "bacteria"?

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In 'The Perfect Predator,' viruses vanquish a deadly superbug

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In 'The Perfect Predator,' an epidemiologist recounts the battle to save her husband from an antibiotic-resistant infection.

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Can sports videogames be used as a motivation/method to get fit?

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Can sports videogames be used as a motivation/method to get fit?

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This article explains why and how  videogames should be used to improve fitness and talks about the health, physical and social benefits of using this new technology.  I believe that this is a very interesting topic and website as most people look down on videogames and think they are a waste of time.

1. How would accessibility of the proper equipment and technology fit into the equation?
2. Would they be workarounds for people who cannot play videogames such as people who suffer from photosensitive epilepsy or Parkinson's disease etc.

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Fitness gaming (aka: active gaming, exer-gaming, exertainment) combines two very popular concepts: video games and fitness. Studies show that people play interactive games for a number of reasons: to have fun, dance, stay fit, meet other people, or simply to enjoy the challenge of the game itself. No matter what the reason, players reap a number of benefits that are intrinsic to each of these activities: the health benefits of exercise and the improved cognitive skills that develop as a positive side-effect of video gaming.

Research into the benefits that fitness games have on health is growing, studies have shown that fitness gaming elevates energy expenditure to moderate or vigorous activity, and can indeed offer the same health benefits as traditional exercise. There is a growing number of studies that support the positive effect fitness gaming has on health, fitness, coordination, anxiety and stress reduction, as well as social, cognitive and problem solving skills, among other things.

The single greatest advantage active gaming has over traditional forms of exercise is that it is not just a physical activity, but also a form of entertainment. Axtion Fitness Games and similar activity-based-video-games offer participants a much higher level of engagement than regular exercise, which significantly reduces the level of perceived exertion in players. As a result, the level of motivation to stick with the exercise program is also much higher than with traditional exercise.

As an additional plus, Axtion Technology provides a fitness solution designed for participants of all ages, which makes the 'stealth health' factor accessible to everyone, regardless of age and fitness level.

Because it is interactive in nature, fitness gaming inspires enthusiasm for exercise, and the combined benefits of these interactive fitness and other fitness games make them an excellent gateway to more demanding forms of exercise, to sports and, by extension, to a healthier lifestyle.

What is Fitness Gaming For? The short term goal of fitness-gaming is to engage children and adults in physical activity as a substitute for sedentary activities. The medium term goal of fitness-gaming is to improve health and fitness of participants, increase self-esteem and physical ability towards the long term goal of increasing physical activity levels for long term healthy lifestyles - including VPA (voluntary physical activity) beyond fitness-gaming alone - and ultimately to realize health and wellness benefits by this.

These are some of the benefits that fitness gaming offers to players:

Health and weight management

Experts agree that an hour of moderate to vigorous exercise a day is essential for children's health. In spite of this, children and teenagers today are growing increasingly used to a sedentary lifestyle, which leads to a number of health issues, even at an early age. While fitness gaming may not be the cure for diseases that come with an inactive lifestyle, obesity being the most frequent one, the engaging nature of the game makes it an extremely fun activity not only for children, but for adults and seniors as well. This makes Fitness Games an excellent choice for anyone who has a hard time staying motivated to exercise. With other forms of exercise, people will usually be thinking about how exhausted they are; with fitness gaming, their mind is immersed in the game and they are just having fun.

When it comes to weight management, experts frequently recommend fitness gaming as a complement to other forms of exercise such as cycling, but for people whose fitness level is relatively low, dance games are an excellent place to start. They burn as many calories or more than a brisk walking pace and, needless to say, the energy expenditure is three times higher than that in sedentary activities.

Fitness gaming can be particularly beneficial to overweight children and those who do not usually participate in any kind of physical activity. For one thing, it provides them with a quality exercise tool and a healthy alternative to the regular kind of video games, which are often blamed for the part they play in childhood obesity. For another, the addictive nature of video games is precisely what makes fitness gaming intrinsically motivating. Another reason why fitness gaming is particularly well suited to overweight children is that they burn more calories during the exercise than normal weight children.

Fitness gaming can also have a beneficial effect on people suffering from type 2 diabetes who often lose interest in various forms of exercise even though treatment requires regular physical activity. While it is not as vigorous an activity as, for instance, running on a treadmill, products like (Twall Interactive, StepManiaX, Nexersys, Immersive Wall Fitness, and Lu Gym) are a lot more engaging and not as demanding on the body when played at lower levels, which encourages people to stick with it and yields better results in the long term.

Physical benefits

Axtion Fitness Games delivers a level of activity similar to the cardiovascular exercise achieved by joggers and runners. Sometimes it even surpasses it, as players get more carried away by the exercise than they would while running.

The physical benefits of Axtion Fitness Games include improved speed, balance, agility, sense of rhythm, coordination, spatial awareness, endurance and reaction time. As an added benefit, all the skills acquired while playing can be transferred to real-world situations.

Cognitive benefits

The interactive aspects of fitness gaming - competition, attention to details in the virtual environment, the need for participants to anticipate events and make decisions - all have a very positive effect on executive functioning as well as on attention, working memory, planning, multi-tasking and problem solving skills. This can be particularly beneficial to seniors, as it helps delay dementia and improve cognitive skills.

Because of their potential to improve children's academic performance and not just physical health, Fitness Games are becoming part of students' physical education classes. With machine dance in particular, researchers have found a positive correlation between the use of the SportGames and StepManiax system and performance in school. The cognitive benefits of Dance & Step Games range from better ordering and sequencing skills to pattern recognition and higher overall competence level.

Studies of sedentary video gaming have shown an improved processing and visual attention capacity, better visual-spatial skills, estimation, pattern recognition, judgment, hypothesis testing, the ability to switch between tasks, and other cognitive skills that improve academic performance. While there are no current studies on the correlation between attention and active video gaming, it is likely that fitness gaming has the same positive effect in this respect as traditional gaming.

Social benefits

Fitness gaming is a social experience. It provides an opportunity to interact with peers with similar interests, which can in turn foster friendships among players.

The multiplayer experience and ability to have people playing at different difficulty levels side by side has a positive effect on self-esteem, especially with children, while the immersive nature of the game gives them a sense of commonality and collaboration. At the same time, the level of any player is never compromised, which gives each player a sense of autonomy. Reduced body self-consciousness is another factor that can contribute to self-esteem, especially with children. The players' attention is always directed at a screen, not at themselves or at other players.

For all these and many other reasons, fitness gaming has become one of the fastest growing market segments in the health games arena in recent years. It is being implemented into physical education curriculum's in schools, and widely accepted in health clubs, senior homes, hospitals, and other recreational and non-recreational settings, both for the health benefits it offers and for its appealing, engaging, fun nature.
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Fitness-gaming exploits the single, most fundamental cause cited for creating the obesity epidemic as the antidote: video games. Contrary to the stereotype, video games are now being used to get kids moving again. This evolutionary stage is called "Fitness-gaming" because it combines exercise with playing entertaining virtual reality games and simultaneous multi player gaming featuring the latest in video and computer technology.

Fitness-gaming's solutions foster social interaction, and allow competition between individuals and groups located in diverse and remote locations leading to the creation of valuable social networks. Fitness-gaming products were created for, and intended to be, a catalyst in transforming today's sedentary kids into healthy active kids. Fitness-gaming makes exercise fun and sustainable, and is a great tool to motivate all kids to get up and exercise.

Fitness-Gaming's products are designed according to the needs and demands of today's kids - colorful, interactive, social, robust, loud, challenging, entertaining, musical, educational, and on walls, floors and ceilings.

Benefits for Children:

A series of studies conducted in recent years have shown that fitness gaming / active gaming is good for children in a number of ways, some of them more surprising than others. Axtion Fitness Games and similar games improve children's agility and coordination, give them the daily dose of exercise they need and, like other types of fitness activities, active games have been known to improve children's academic performance. However, unlike many other forms of exercise that are just as good for them, fitness gaming / active gaming is also an activity that children tend to enjoy. Because Fitness Games are designed to engage kids in a video game, one that requires them to perform physical tasks in order to score points and move from one level to the next, children tend to take to them pretty quickly.

Almost a half of preschool children do not get an hour of exercise a day, which is the level of physical activity recommended by the American Academy of Pediatrics. The reasons why kids don't exercise enough range from a lack of motivation and competence to insufficient support from parents and friends. Yet the main reason why children do not get as much exercise as they should is the same as the reason why they do exercise when they do: because it's fun. Some children find different forms of physical activity fun, while others find video games and TV programs more entertaining. For this reason, a growing number of schools - and families - have recognized the benefits and appeal of active video games and begun introducing them to their children.

Fitness Games are increasingly becoming part of the curriculum at schools not only to make exercise more fun for children, who are already used to spending a lot of time playing sedentary video games, but also to motivate kids to exercise more. Twall Interactive, like other fun active games, does not only eliminate the usual barriers to physical activity, mainly the lack of interest, but also inspires enthusiasm for exercise, which is essential to long term success in making a fitness workout part of their daily routine.

What makes Lu Gym, StepManiaX, Twall, Active Wall and similar games particularly appealing to children is that they can play with their friends and family. The camaraderie and support in a group exercise motivate kids to stick with the workout routine. The video game aspect, being intrinsically motivating, leaves children more energized and can inspire them to engage in sports and other vigorous activities that involve group play.

Here are some of the factors that children who play active video games benefit from:

Improved fitness level and physical skills

The amount of energy expended in fitness gaming / active gaming is equal to that in moderate or vigorous exercise, depending on the players' level. Like any other form of exercise, Twall Interactive and other active games have a beneficial effect on health and can significantly improve children's agility, motor skills and cardiovascular endurance, as well as their sensory motor learning. Active games that encourage players to jump and maintain balance are known to improve balance by up to 30% in the long term!

The physical skills acquired through fitness gaming / active gaming include balance, improved reaction time, endurance, coordination and speed. As an additional benefit, these skills are transferable to other activities and have the potential to boost physical activity in children and motivate them to engage in traditional forms of exercise and sports. This in turn benefits their physical, cognitive and social development even more down the line.

Fitness gaming / active gaming is known to improve levels of activity in students. Schools that have introduced fitness gaming / active gaming to their curriculum have recorded a 33% increase in activity, as active video gaming is an activity children genuinely enjoy.

Weight loss

Childhood obesity and lack of physical activity among children have grown to epidemic proportions in western countries in recent decades. Other than increasing the risk of cardiovascular disease and type 2 diabetes, obesity has a number of other negative effects on children, with their self-esteem and motivation being the first in the line of fire. Video games, computers, television and other screen activities are often blamed for the decrease in physical activity in children and teenagers.

Fitness gaming / active gaming and machine dance can assist in weight loss. While the energy expenditure depends on the level of the game, research has shown that active video gaming has a small but definite effect on the body mass index in obese and overweight children, and that time spent playing active games tends to increase. Studies of individual Fitness Games over a longer period of time have yet to be conducted, but the existing ones show that the moderate exercise required to complete tasks and the reduction of sedentary activity and everything that usually comes with it (snacks, for one thing) can indeed help children lose weight and improve their body composition. Among different types of Fitness Games studied so far, dance games are the ones with the highest energy expenditure level. While playing, children burn three times as many calories than at rest.

Academics

Both children who engage in sports and those who play passive video games benefit from their hobbies, as each activity has a positive effect on their cognitive skills by itself. Research has shown that video games improve a number of factors that are vital to children's academic performance, including their attention capacity, problem solving skills, pattern recognition, task switching ability, hypothesis testing, and estimation among other things. Physical activity, on the other hand, is known to improve cognitive skills in children and adolescents, including their perceptual and verbal skills, developmental level, and even their intelligence quotient. This is why exercise is vital for children and adolescents, as it affects how their brain develops and has a longer lasting effect compared to the one fitness activities have on adults and seniors.

Like other vigorous physical activities, fitness gaming / active gaming is known to improve academic performance among students by building new neurological connections that enhance memory, learning and critical thinking. Schools that have introduced fitness gaming / active gaming to their activities have recorded a grade average increase by 1.5 grades, reading scores 17% higher than the state average, and math scores 18% better than the state average. As an aside, schools that use Fitness Games to boost their students' activity level in the morning are seeing a significant decrease in tardiness.

The level of fitness that results from fitness gaming / active gaming and other forms of aerobic exercise enhances neurological and physiological mechanisms, increases neurotransmitter availability and cerebral circulation, and these processes lead to an improved cognitive performance. With Axtion Fitness Games and other games similar in nature, children also benefit from an improved attention capacity, better processing skills and task-switching ability. All these factors can and often do result in a better performance at school.

Social benefits

Active gaming can be particularly appealing to shy, withdrawn children, who do not usually engage in group activities easily and who sometimes do not get enough exercise to stay healthy for this very reason. Fitness gaming / active gaming allows them to both play games and get some exercise without leaving the house. In a group exercise, it helps that the players are focused on the arrows on the screen and their attention does not drift from completing the task to their body or performance compared to others. This can be liberating for children who are too self-aware or not very talented at sports. Without the competitiveness and pressure to perform on a team that comes with other group activities, children's progress and competence level can also have a positive effect on their self-esteem. Beyond that, like any other kind of exercise, active games help decrease stress levels and improve mood.

Even though kids should get at least some of their exercise outside, fitness gaming / active gaming is an excellent supplement to their other activities and, needless to say, an excellent alternative to sedentary video gaming, surfing the internet, watching television, and other activities kids usually engage in at home. In addition to that, games like StepManiaX, ValoClimb, Nexersys which have grown into a global phenomenon, have also built a global social network of players. This allows children and adolescents to share experiences, socialize online, and find new friends who share similar interests.

Blog: Interactive Fitness Technology - Buying Guide

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Fitness gaming (aka: active gaming, exer-gaming, exertainment) combines two very popular concepts: video games and fitness. Studies show that people play interactive games for a number of reasons: to have fun, dance, stay fit, meet other people, or simply to enjoy the challenge of the game itself.

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Fasting vs dietary restriction in cellular protection and cancer treatment

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How Venus flytraps store short-term ‘memories’ of prey

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How Venus flytraps store short-term ‘memories’ of prey

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This article explains the discovery of the mechanics in a Venus flytrap’s short-term “memory”. Venus flytraps's have a short term "memory" which lasts around 30 seconds and have sensitive hairs which detect touch. If an insect touches one of these hairs the trap stays open, but if the insect touches the hairs again within 30 seconds then the trap will shut. This article outlines the new discovery which has found evidence for the direct involvement of calcium in this process. The researchers added genes to the Venus fly trap which produced proteins that glowed when exposed to calcium.  "The results show that the flytrap’s short-term memory is a waxing and waning of calcium within leaves’ cells". The researchers found that once a certain concentration of calcium was achieved by the second touch the trap would close. I find this interesting as it is cool to see the adaptations this plant has done to be more energy efficient e.g not closing everytime it's touched by rain

Questions
1. Do Venus flytraps have a long term memory, and if so how does this process differ from it? (e.g is this process similar to vernalization)
2. How does this plants short term memory mechanism differ from others and why?

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How Venus flytraps store short-term 'memories' of prey

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A Venus flytrap's short-term "memory" can last about 30 seconds. If an insect taps the plant's sensitive hairs only once, the trap remains still. But if the insect taps again within about half a minute, the carnivorous plant's leaves snap shut, ensnaring its prey.

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Coronavirus-infected cells sprout filaments that may spread the virus

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Coronavirus-infected cells sprout filaments that may spread the virus

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Researchers have found that human cells infected with SARS-CoV-2 (COVID-19) formed numerous probing appendages (a.k.a. Filopodia) that contain the virus budding off its projections.

I find this interesting, because I did not consider the virus to use the cell's filopodia in order to spread to other cells. It also means that many other diseases use these cellular projections to seem to efficiently infect other cells.

1. Do these abnormal protrusions create any additional adverse effects on the already infected cell?

2. How can scientists use this discovery to their advantage in developing an effective drug treatment against SARS-CoV-2 and other pathogens that also cause these increased number of filopodia?

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Like a scene out of a sci-fi movie, cells invaded by the coronavirus can sprout probing appendages bedecked with viral bits.

Human cells infected with SARS-CoV-2, the coronavirus that causes COVID-19, formed more numerous and longer extremities, called filopodia, than uninfected cells, researchers report online June 28 in Cell. High-resolution electron microscopy confirmed the presence of these filopodia in infected monkey cells and captured SARS-CoV-2 viral particles budding from the projections. These protrusions may have unexplored roles in spreading the virus, and could serve as targets for future antiviral therapies.

Similar spindly projections are found on some healthy cells, where the structures serve different roles. Repair cells, for example, send out filopodia to detect chemical cues to navigate to wound sites.

Other viruses, including the coronavirus behind the SARS epidemic, also can cause cells to sprout filopodia. Some viruses, such as Marburg and Ebola, travel along filopodia of infected cells and may use the structures to move directly from one cell to another.

The extensions "are highways for transport," says Robert Grosse, a cell biologist at the University of Freiburg in Germany.

Robert Grosse/CIBSS/University of Freiburg

More work is needed to confirm what role filopodia play in a COVID-19 infection. Microscopy of infected cells over time would provide insight into whether these cell-to-cell connections affect viral spread, says Mark Denison, a virologist at Vanderbilt University Medical Center in Nashville not involved in the study.

The filopodia observed in the new study contained a protein called CK2. Cells dosed with silmitasertib, a CK2-inhibiting molecule in clinical trials for various cancers, were more resistant to a SARS-CoV-2 infection than untreated counterparts. That suggests that CK2 could be a target for future coronavirus drug treatments, Grosse says ( SN: 3/10/20).

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Questions or comments on this article? E-mail us at feedback@sciencenews.org

Jack J. Lee is the Summer 2020 science writing intern. He has a bachelor's degree in biology and a Ph.D. in molecular biology, and recently completed a master's program in science communication.

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Coronavirus-infected cells sprout filaments that may spread the virus

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Like a scene out of a sci-fi movie, cells invaded by the coronavirus can sprout probing appendages bedecked with viral bits. Human cells infected with SARS-CoV-2, the coronavirus that causes COVID-19, formed more numerous and longer extremities, called filopodia, than uninfected cells, researchers report online June 28 in Cell.

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Is it a bird, a plane? Not superman, but a flapping wing drone

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Is it a bird, a plane? Not superman, but a flapping wing drone

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A team of international engineers designed a drone which can mimic the aerobatic manoeuvres of one of the world's fastest birds.

"A research team from Singapore, Australia, China and Taiwan has designed a 26 gram ornithopter (flapping wing aircraft) which can hover, dart, glide, brake and dive just like a swift, making them more versatile, safer and quieter than the existing quadcopter drones."

https://www.sciencedaily.com/releases/2020/07/200722142724.htm

1. Could there be military implementations such as stealth objects to make it safer for soldiers to get data for their environment?

2. Would this have an autonomous flight path? As it would be hard to manually control the wings, tail, body etc of the drone all at once in unanimity.

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Sound can only travel at 36 km per second under normal Earth conditions

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Sound can only travel at 36 km per second under normal Earth conditions

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The fastest measured speed so far is diamond, with a maximum allowed speed of less than half this new limit.

https://www.sciencenews.org/article/sound-new-speed-limit-physics-fundamental-constants-earth

This limit can be broken at pressures millions of times Earth's atmosphere.

1. This speed is derived from physical constants, so does it hint at anything bigger?

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Cable ties probably won’t stop magpie attacks – here are a few things to try instead

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Cable ties probably won’t stop magpie attacks – here are a few things to try instead

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https://theconversation.com/cable-ties-probably-wont-stop-magpie-attacks-here-are-a-few-things-to-try-instead-123759

At one point in our lifetime, people have been swopped by magpies (  Cracticus tibicen) in Australia. Their musical cries only mask the violent intent , as their red devilish eyes mark their next target and claw and swoop until the victim are running for their life. Especially during spring, magpies swooping's occur at a rapid rate as their animal trait is developed to protect their young, while its the females who lay the eggs it the male magpie who is the culprit for magpie swoopings. However while their intention might be innocent, their continuous appearance every spring and affect on the people swooped is not. Cyclists, runners and normal people walking are always at the risk of being swooped. Before this pandemic, personally last year I was swooped numerous and left running for my life. This begs the question what are methods to avoid being swooped by a magpie. As a person who rides a bike cable ties is not an efficient method in magpie protection as instead  of going for the head they turn to the face. One way of protection is to wear clothes or assortments that can help you escape a swooping like wearing sunglasses or wearing a mask to protect your face and eyes. Even pedestrians who are regularly  swooped can opt for methods like wearing wide brimmed hats or cover their heads with anything as it is their primary target. However there are unconventional methods like befriending the magpie before swooping season, magpies for birds have excellent memory and can recognise faces exceptionally well and with patience and food magpies can become companions. Yet the most important thing to is to always remain calm. With this hopefully you can survive spring unscathed.

Questions.
1. Has there been an instance where a victim of magpie swooping been killed?

2. How did magpies develop this nature of swooping individuals who are close to their young?

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Baby macaques are the first primates to be cloned like Dolly the Sheep

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Baby macaques are the first primates to be cloned like Dolly the Sheep

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https://www.sciencenews.org/article/baby-macaques-primates-clones-dolly-sheep

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Fasting vs dietary restriction in cellular protection and cancer treatment

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Fasting vs dietary restriction in cellular protection and cancer treatment

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I find this quite interesting because this research could definitely be implemented into the treatment of cancer patients, and significantly reduce the implications of chemotherapy. Basically allowing cancer patients to undergo chemotherapy more comfortably and with fewer side effects, while also increasing the uptake of chemotherapy as a treatment.

1. Can the capabilities and effects of fasting, in cancer, be translated to certain Autoimmune diseases?

2. How much more research would need to be conducted for this to be incorporated into cancer treatment.

- Crystal

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Introduction

For the past 50 years, chemotherapy has been a major medical treatment for a wide range of malignancies ( Chabner and Roberts, 2005). Its main strategy has been largely based on targeting malignant cells, by means of genotoxicity caused in part by the production of reactive oxygen species ( Sangeetha et al., 1990; Look and Musch, 1994; Faber et al., 1995; Conklin, 2004). In fact, the US Food and Drug Administration has approved 132 cancer chemotherapy drugs, of which 56 have been reported to cause oxidative stress ( Chen et al., 2007). Although these drugs were first believed to be quite selective for tumor cells, we now know that normal cells also experience severe chemotherapy-dependent damage, leading to dose-limiting side effects including myelosuppression, fatigue, vomiting, diarrhea and in some cases even death. Chemoprotectants such as amifostine, glutathione, mesna and dexrazoxane have been investigated and shown to provide drug-dependent protection to certain tissues, but these drugs have not been shown to increase disease-free or overall survival, in part because they may also protect cancer cells ( Links and Lewis, 1999). Despite the focused efforts on the development of drugs designed to specifically target certain cancer cells, side-effects will continue to accompany cytotoxic drugs as well as a wide range of antibody-based drugs until fundamentally novel strategies to selectively eliminate malignant cells are discovered.

Fasting has been demonstrated to selectively protect normal cells and mice, but not cancerous cells against oxidants and common chemotherapeutic agents ( Longo et al., 1997; Raffaghello et al., 2008). In cancer patients, preliminary data suggest that fasting is not only safe and feasible, but may also be effective in reducing common side-effects associated with chemotherapy ( Safdie et al., 2009). In this review, we discuss how short-term fasting can selectively protect normal cells and organisms from chemotherapy toxicity without interfering with its therapeutic effect ( Figure 1), and also compare its effects with those of the much better studied dietary restriction (DR) ( Table 1). We also discuss the evolutionarily conserved role of the growth hormone (GH) and insulin-like growth factor 1 (IGF-I) signaling pathways in stress resistance, and how they act as major mediators of fasting-dependent differential protection against chemotherapy and oxidative toxicity ( Fontana et al., 2010). Finally, we discuss how these studies may provide grounds for future investigations on the role of various dietary interventions in enhancing cancer treatment.

Fasting provides differential stress resistance (DSR) to chemotherapy. The investment of the finite energy available in a cell or an organism is efficiently balanced between growth/reproduction and maintenance/repair. However, challenging conditions, such as fasting and its consequent reduction of IGF-I, withdraws energy from growth/reproduction and reinvests it in maintenance/repair, thereby increasing cellular protection. This switch in cellular metabolic policy is mediated by negatively regulating mitotic pathways such as those major effectors downstream of IGF-I (PI3K/Akt and Ras/ERK). By contrast, oncogenic mutations, which often regulate cellular metabolism and growth, render tumor cells less responsive to fasting due to their independence from external cues. Therefore, cancer cells fail to or only partially respond to fasting and continue to promote growth, leaving them vulnerable to chemotherapy drugs.

Table 1 Fasting and dietary restriction (DR) induce similar, yet distinct physiological response in laboratory rodents

Starvation and stress resistance

Most organisms live in environments of fluctuating food availability, where starvation is a commonly encountered condition. Thus, nutrient depletion has been an evolutionary driving force, selecting for organisms able to withstand starvation. Because during periods of food scarcity organisms are exposed to a wide variety of insults including UV radiation, heat, cold and so on, adaptation to starvation requires the organism to invest energy into multiple protective systems to minimize the damage that would reduce fitness ( Madia et al., 2008, 2009). For example, yeast switched from glucose and ethanol medium to water becomes resistant to multiple types of stress and long-lived ( Longo et al., 1997; Fabrizio et al., 2005; Wei et al., 2008). As discussed later, pro-growth pathways, including those activated by nutrients or growth factors, have central roles in the prevention of the entry into this protected mode.

DR is a term commonly used to describe a 20-40% reduction in calorie intake, although it can also refer to more or less severe restrictions or to reduced or lack of daily intake of particular components of the diet, such as amino acids, protein or fats. Although DR could also describe the complete lack of food or calorie intake, we will use the terms fasting or starvation to avoid confusion with the more common use of DR. Both DR and fasting have been shown to promote stress resistance as well as longevity in model organisms ranging from unicellular yeast to mammals in part, by downregulating conserved nutrient-signaling proteins, or by activating stress resistance transcription factors negatively regulated by these pro-aging pathways ( Figure 2) ( Fontana et al., 2010). These pathways have many regulatory effects including those on cellular growth, metabolism and protection against oxidants and other toxins.

Fasting leads to a significant reduction in circulating IGF-I levels. The partially conserved IGF-I signaling pathways negatively regulate the FoxO family of transcription factors through Akt. Ras and Tor also function downstream of IGF-I, although their roles in the regulation of stress resistance and aging are poorly understood. Mice deficient in type 5 adenylyl cyclase (AC) are stress resistant ( Yan et al., 2007). Notably, oncogenic mutations that cause the hyperactivation of IGF-I, Akt, Ras, mTOR and PKA are among the most common in human cancers ( Hanahan and Weinberg, 2000).

The reactive oxygen species generated in response to many chemotherapy drugs can cause a wide range of genetic aberrations including DNA strand breaks and base/nucleotide modifications ( Burney et al., 1999). Notably, a functioning immune system is required to delay cancer growth or promote cancer regression in response to several chemotherapy drugs, indicating that oxidative damage may, in many cases, impair the cells sufficiently to be detected and destroyed by the immune system, thereby reducing chemotherapy efficacy ( Locher et al., 2010; Ma et al., 2010). For example, natural killer T cells are required for the toxic effect of oxaliplatine and irradiation on cancer cells, which also target rapidly dividing normal immune cells ( Locher et al., 2010).

One of the most common reactive oxygen species-mediated DNA modification is the conversion of guanine to 7, 8-dihydro-8-oxoguanine (also known as 8-oxoguanine; 8-oxoG) ( David et al., 2007). This damage can lead to mutations in nuclear and/or mitochondrial DNA, but can also cause epigenetic alterations, leading to cellular dysregulation and malignant transformation. Simple organisms such as yeast and bacteria, in part because of their inability to escape harsh environments, have evolved systems that can increase resistance to many insults, in some cases by several orders of magnitude. This protected mode appears to be at least partially conserved in many species. In the prokaryote E. coli, lack of glucose or nitrogen (comparable to protein restriction in mammals) increase resistance to high levels of H ₂O ₂ (15 mM) ( Jenkins et al., 1988). In many bacterial species, starvation induces the stationary-phase-specific σ factor RpoS expression, which in turn controls a large set of stress defense genes, in particular oxidative stress ( McDougald et al., 2002). In yeast, glucose reduction (2-0.5%) increases protection against oxidative stress, whereas complete starvation by switching the population of cells to water, promotes protection to oxidative insults and heat shock and a major life span increase ( Longo et al., 1997; Wei et al., 2008). Although the precise molecular mechanisms of increased protection by fasting have yet to be described in detail, in yeast they involve the reduced activity of the Ras/cAMP/PKA and the Tor/S6K nutrient signaling pathways and the activation of transcription factors downregulated by these pathways ( Thevelein and de Winde, 1999; Wei et al., 2008). In fact, deletion of transcription factors Msn2/Msn4 and Gis1 reverses the protection caused by glucose restriction or starvation conditions, suggesting an important role for genes involved in metabolism, cellular protection and repair regulated by these factors in starvation-dependent stress resistance ( Longo et al., 1997; Wei et al., 2008).

Worms also increase their defenses against oxidative insults during fasting. Every 2 days fasting increases the resistance to oxidative stress, as well as lifespan of worms up to 56% via modulation of the RHEB-1 and TOR signaling pathway, both of which are linked to the FOXO transcriptional factor homolog DAF-16 ( Weinkove et al., 2006; Honjoh et al., 2009). Conversely, excessive glucose shortens the lifespan of worms, in part, by decreasing DAF-16 activity ( Lee et al., 2009).

In flies, fasting-dependent protection against oxidative stress is mediated by d4E-BP, which acts downstream of the PI3K/Akt/dFOXO3 pathway ( Tettweiler et al., 2005). d4E-BP binds to eIF4E and represses translation. During fasting, flies increase the expression of d4E-BP, thereby suppressing eIF4B-dependent translation, a mechanism consistent with the necessity to divert energy from growth to protection. Notably, flies under moderate DR are not protected against oxidative damage following anoxia/reoxygenation injury, whereas a severe DR, that is near starvation, is able to reduce damage ( Vigne et al., 2009).

As discussed in more detail later, in mice, fasting for 48-60 h increases protection from oxidative stress and protects three different strains of mice to etoposide, a drug known to promote oxidative stress, with remarkable improvement in survival compared with its normally fed counterparts ( Raffaghello et al., 2008). In addition, 72-h of fasting protects the outbred CD-1 mice from lethal doses of doxorubicin, a drug also known to cause death by oxidative stress-induced cardiotoxicity ( Lee et al., 2010). Studies also show that fasting protects against ischemia injury in rat brain ( Go et al., 1988; Marie et al., 1990), mouse kidney and liver ( Mitchell et al., 2009; van Ginhoven et al., 2009), and human liver ( van Ginhoven et al., 2009). Also, fasting following traumatic brain injury proved to be neuroprotective, resulting in reduced oxidative damage and improved cognitive function ( Davis et al., 2008).

Conserved role of nutrient signaling pathways in stress resistance

Nutrient signaling pathways controlled by insulin and/or the GH/IGF-I axis are major regulators of both lifespan and stress response as demonstrated by studies in S. cerevisiae, C. elegans, D. melanogaster and mice ( Longo, 1999; Guarente and Kenyon, 2000; Kenyon, 2001; Longo and Finch, 2003b). In yeast, decreased Ras/adenylate cyclase and/or Tor/S6K (SCH9) increases lifespan by more than 200%, while providing increased stress resistance against oxidants, genotoxins, and heat-shock ( Fabrizio et al., 2001, 2003; Longo and Finch, 2003b; Wei et al., 2009). Similarly, in C. elegans, age-1 (PI3K homolog) and daf-2 (insulin/IGF-I receptor homolog) mutations extend the life-span in adult organisms by 65-100% by decreasing AKT-1/AKT-2 signaling, and by activating the transcription factor DAF-16 (FOXO family member), while promoting resistance to oxidative and ER stress ( Johnson, 1990; Paradis et al., 1999; Hsu et al., 2003; Henis-Korenblit et al., 2010). Also, DAF-16 is thought to be negatively regulated by PtdInsP ₃, which is regulated by the PI3K homolog AGE-1; AGE-1 mutants have been shown to be resistant to oxidative stress ( Larsen, 1993; Morris et al., 1996). These longevity mutations are largely associated with the induction of stress resistance transcription factors, superoxide dismutase (MnSOD), and heat shock proteins (HSPs) in both yeast and worms ( Longo and Finch, 2003a; McColl et al., 2010). In D. melanogaster, mutations in the insulin receptor substrate (chico) extend lifespan, but its role in stress resistance is not clear ( Clancy et al., 2001; Giannakou and Partridge, 2007). In mice, stress resistance and lifespan are controlled by the GH/IGF-I axis and the downstream orthologs of the genes that regulate stress resistance and/or life span in yeast and worms ( Brown-Borg et al., 1996; Migliaccio et al., 1999; Coschigano et al., 2000; Holzenberger et al., 2003; Yan et al., 2007; Bonkowski et al., 2009; Selman et al., 2009). In agreement with the findings in lower eukaryotes, the activities of anti-oxidant enzymes superoxide dismutases and catalase are decreased in murine hepatocytes exposed to GH or IGF-I and in transgenic mice overexpressing GH ( Brown-Borg and Rakoczy, 2000; Brown-Borg et al., 2002). In addition, cultured cells derived from long-lived mice with deficiencies in the GH/IGF-I axis are resistant to oxidative stress (H ₂O ₂, paraquat), UV, genotoxins (methylmethanesulfonate; MMS), heat and cadmium ( Salmon et al., 2005; Murakami, 2006), even though they are cultured in standard medium, suggesting that some of the protective effects observed in long-lived organisms may be also due to epigenetic changes acquired during chronic exposure to reduced growth factors.

In rats, IGF-I attenuates cellular stress response and the expression of stress response proteins HSP72 and heme-oxygenase ( Sharma et al., 2000). In primary neurons IGF-I sensitizes cells to oxidative stress by a Ras/Erk-dependent mechanisms ( Li et al., 2008), and experiments in rat primary glia and mouse fibroblasts suggest that IGF-I sensitizes against oxidative damage and chemotherapy drugs ( Lee et al., 2010).

Together, the results from the range of studies and organisms described above indicate that enhanced stress resistance is a highly conserved phenotype of starved and long-lived organisms, which is partially mediated by downregulation of GH and IGF-I signaling.

DR and cancer treatment

Chronic moderate DR (20-40%) has been shown to promote protective effects in a range of organisms. Tumors rise from a combination of DNA damage and mutations and changes in the environment surrounding pre-cancerous cells ( Hanahan and Weinberg, 2000). Not surprisingly, aging, which promotes all the components listed above, is the major risk factor for cancer ( DePinho, 2000; Wedding et al., 2007; Campisi and Vijg, 2009; Jemal et al., 2010). It has been 100 years since the first report on the direct relationship between the amount of food intake and the growth or transplanted tumors in mice showing that severe DR prevented tumor transplantation ( Moreschi, 1909). Since then, a large body of work has established that DR reduces the progression of tumors in various animal models ( Tannenbaum, 1945; Hursting et al., 1994). However, recently it has been shown that specific oncogenes render tumors unresponsive to DR, suggesting that the efficacy of a reduction in food intake may be limited to a subset of cancers ( Kalaany and Sabatini, 2009).

DR has also been shown to reduce cancer incidence. For instance, an 'adult-initiated' DR ('undernutrition without malnutrition') beginning at 12 months of age not only increases life-span, but also reduces spontaneous cancer incidence by more than 50% ( Weindruch and Walford, 1982; Weindruch et al., 1982). Furthermore, DR initiated at the time of weaning increased lifespan and reduced tumor incidence in mice ( Weindruch et al., 1986), confirming the DR studies in rats. These studies have been extended to primates with a 20-year longitudinal study in rhesus monkeys showing that DR (30%) delays disease onset and mortality, in part by causing a 50% reduction in cancer incidence ( Colman et al., 2009). Whether or not DR will reduce cancer incidence in humans is still unclear. However, DR can reduce clinical markers associated with cancer, analogously to its effect in rodents ( Longo and Fontana, 2010).

The absence of DR in clinical cancer treatment after so many decades of laboratory findings reflects the limited potential of a chronic reduction in calorie intake in cancer treatment. Among the problems associated with the translation of DR into clinical applications is that chronic DR delays but does not stop the progression of the disease ( Mukherjee et al., 2004; Bonorden et al., 2009; Shelton et al., 2010), and that this delay will occur for only a subset of malignancies ( Kalaany and Sabatini, 2009). Although weight loss and cachexia in the early stages of cancer progression are not as common as thought ( Tisdale, 2002; Fearon et al., 2003; Fox et al., 2009), the ∼15% loss of body mass index caused by a moderate (20%) calorie restriction ( Racette et al., 2006) would prevent its use in the great majority of cancer treatment scenarios. In addition, the effect of long-term restriction in delaying wound healing and impairing immune function ( Fontana et al., 2010; Kristan, 2008; Reed et al., 1996) may impose a significant risk to cancer patients receiving chemotherapy, surgery or immunity-based treatments ( Kim and Demetri, 1996).

Intermittent fasting (IF), where fasting is applied every other day, has been also shown to extend healthy lifespan and reduce cancer incidence without causing weight loss ( Goodrick et al., 1983; Varady and Hellerstein, 2007). However, the role of IF in combination with chemotherapy is not known. More importantly, because IF requires weeks-months to be effective, it may be more useful for cancer prevention than for cancer treatment. Nonetheless, it will be important to compare the efficacy of IF with that of prolonged fasting (short-term starvation), described in the following section.

Fasting vs DR in cancer treatment

Even if the side effects and limitations of chronic DR and IF were eliminated or reduced to a tolerable level, initial data suggest that prolonged starvation in the 2-3 days range for mice and 4-5 days range for humans has the potential to cause a much stronger protection of the host as well as changes which may retard the growth of cancer cells, without unwanted side effects. For example, the decrease in blood glucose caused by short-term fasting in mice is 75% vs the 15% caused by long-term DR or IF ( Heilbronn et al., 2005; Holloszy and Fontana, 2007). Similarly, the 75% reduction in blood IGF-I caused by a 2-5-day fast in mice and humans ( Clemmons and Underwood, 1991; Lee et al., 2010) is not matched by DR, which causes a 25% IGF-I reduction in mice ( Barger et al., 2008) and does not reduce IGF-I levels in humans unless protein intake is also restricted ( Fontana et al., 2008). Even together with protein restriction, chronic DR only causes a ∼30% reduction in IGF-I ( Fontana et al., 2008).

The physiology of fasting

Although the effects of DR are often viewed as responses that have evolved to adapt to a relatively small (10-40%) reduction in food intake below the normal laboratory food intake established for a particular organism, it is more likely that they have evolved to adapt to long periods of complete starvation. Clearly, all organisms ranging from bacteria to humans have undergone periods of starvation alternated with periods of food availability. This is not only true for bacteria or yeast that can spend weeks or months under starvation conditions, but is also true for mammals. In fact, humans, for example, have encountered many and long periods of famine in their history and can survive for over 1 month on water only. For example, populations in Europe and Asia experienced frequent and severe famines, which in some cases caused hundreds of thousands of deaths ( Scrimshaw, 1987).

The physiological response to fasting is quite different from that to DR ( Table 1). In mammals, there are three metabolic stages during food deprivation ( Wang et al., 2006). First, the post-absorptive phase, which can last for 10 or more hours following food ingestion and involves the use of glycogen as the main stored energy source. When the liver glycogen storage has been depleted, it is followed by the second phase in which amino acids serve as the substrate for gluconeogenesis. Eventually glycerol and fatty acids released from adipose tissues become the major source of energy. The remaining glucose is mostly consumed by the brain, and the newly fat-derived ketone bodies (that is acetoacetate, β-hydroxybutyrate and acetone) become the major carbon sources in a matter of days ( Cahill, 1970; Cahill et al., 1970; Cahill, 2006). Following prolonged fasting lasting a week or longer, fat-derived β-hydroxybutyrate becomes the most abundant ketone body, accounting for roughly two thirds of brain fuel, and glucose production reaches a very modest level ( Cahill, 2006). During the last phase of prolonged food deprivation, fat reserves are eventually exhausted and rapid muscle degradation occurs to fuel gluconeogenesis. In rats, this occurs after 4-5 days but does not result in a major increase in glucose levels ( Wang et al., 2006). Weight loss caused by fasting is initially rapid but subsequently tapers off as shown in a human study, in which an average of 0.9 kg/day was lost during the first week of fasting, followed by a 0.3 kg/day weight loss by the third week of fasting. This study also reported an approximately 20% body weight loss caused by 30-35 days of fasting ( Kerndt et al., 1982). It is estimated that a 70 kg person can obtain basal caloric requirements from fat reserves during up to 2-3 months of fasting ( Cahill and Owen, 1968; Cahill et al., 1968; Saudek and Felig, 1976). Thus, prolonged fasting is feasible and generally well tolerated in humans, but may be accompanied by relatively minor side-effects, such as headaches, light-headedness, nausea, weakness, edema, anemia and amenorrhea ( Bloom, 1959; Drenick et al., 1964; Thomson et al., 1966). In some rare cases, extreme fasting for periods of several weeks or longer in obese subjects has been reported to cause fatal complications such as renal failure, heart failure and lactic acidosis ( Cubberley et al., 1965; Spencer, 1968; Garnett et al., 1969; Runcie and Thomson, 1970). Prolonged fasting can also cause severe problems and possibly death, as it occurred in some prisoners of concentration camps after they were liberated, if the re-feeding period is not gradual. Further, fasting should be limited to subjects that do not have deficiencies in metabolic pathways. For instance, patients with deficiencies in gluconeogenesis (for example, mutation in fructose-1,6-bisphosphatase), are known to experience hypoglycemia, acidosis, as well as failure to produce ketone bodies during fasting, rendering them highly susceptible to this severe restriction ( van den Berghe, 1996).

Adaptation to starvation also occurs at the cellular level. A key survival mechanism a cell employs is self-eating, or autophagy, which is also activated in response to cellular stress (for example, chemotherapy) in various eukaryotes. For example, starving mammalian cells of essential nutrients (for example, glucose) and growth factors (for example, serum) induces autophagy, and starving mice for 12-24 h triggers autophagy in various tissues ( Kroemer et al., 2010; Marino and Kroemer, 2010). Interestingly, autophagy is regulated by several genes, such as AMPK, mTOR, and sirtuins, which are also known to regulate aging and stress resistance ( Morselli et al., 2009; Kroemer et al., 2010; Marino and Kroemer, 2010). Many oncogenic signals (for example, PI3K and Akt) inhibit autophagy, whereas tumor suppressors (for example, PTEN and TSC2) trigger autophagy. Surprisingly many cancer cells display elevated autophagy, an increase which was recently suggested to be mediated by ammonia, a by-product of glutaminolysis that preferentially occurs in the mitochondria of malignant cells undergoing the Warburg effect ( Vander Heiden et al., 2009; Marino and Kroemer, 2010). Under the Warburg effect, mitochondria takes on a different role to supply biosynthetic precursors that are required for the rapid proliferation rate set by oncogenic mutations ( Vander Heiden et al., 2009). Therefore, autophagy triggered by fasting may be beneficial to normal cells but detrimental to malignant cells. In fact, considering that autophagy increases the resistance of cancer cells to chemotherapy ( Marino and Kroemer, 2010), it will be important to determine whether fasting promotes cancer sensitization alone or in combination with fasting.

Fasting, glucose and growth factors

Glucose levels undergo remarkable changes during food restriction, and can reach 50-60 mg/dl in a healthy person after only 72 h of fasting, but return to normal levels within 30 min of administering 100 g of glucose orally ( Unger et al., 1963). Fasting also reduces a plethora of extrinsic and intrinsic growth factors, particularly the insulin-like growth factor 1 (IGF-I), which acts as the major growth effector of growth hormone. If both the reduction and the rate of decrease are considered, the effect of fasting on the GH/IGF-I axis is unlikely to be surpassed by any other intervention including Food and Drug Administration approved drugs such as pegvisomant, a GH receptor antagonist. As described earlier, the GH/IGF-I axis is also a major regulator of metabolism and activates evolutionarily conserved pathways that promote stress sensitivity and aging ( Fontana et al., 2010). In humans, IGF-I levels decrease dramatically in response to a short-term starvation (36-120 h) despite increased GH secretion, which is highly lipolytic ( Merimee et al., 1982; Isley et al., 1983; Thissen et al., 1999; Maccario et al., 2001; Norrelund, 2005; Moller and Jorgensen, 2009). This effect may be the result of a major increase in the IGF-I inhibitory protein IGFPB-1 ( Zapf, 1995), which decreases further IGF-I bioavailability and prevents the feedback inhibition of GH secretion by IGF-I ( Muller et al., 1999). Notably, the 65% reduction in IGF-I levels induced by fasting for 5 days persisted 24 h after re-feeding, and only reached 70% of normal levels even 5 days after normal feeding ( Isley et al., 1983). In non-obese subjects GH levels eventually level off and drop between 3-10 days of fasting ( Cahill et al., 1966; Merimee and Fineberg, 1974; Palmblad et al., 1977). In mice, a short-term starvation (24-72 h) decreases IGF-I production by 70% and causes an 11-fold increase in its inhibitory partner IGF-binding protein 1 (IGFBP-1) ( Tannenbaum et al., 1979; Frystyk et al., 1999; Lee et al., 2010). In response to fasting, mice also show reduced protein synthesis, reduced AKT activity via TRB3, a mammalian homolog of Drosophila tribbles ( Du et al., 2003), reduced mTOR/S6K, increased 4E-BP1 activity ( Sans et al., 2004) and increases FOXO-1, -3, -4 ( Imae et al., 2003).

Differential stress resistance (DSR) by fasting

Whereas the inactivation of partially conserved pro-aging pathways increases resistance to oxidative and other stresses in lower eukaryotes, the constitutive activation of analogous pathways is known to promote cancer. In fact, both Ras and Akt, whose orthologs are central in stress sensitization in yeast and worms, function in signal transduction pathways that are among the most frequently found in a constitutively activated form in human cancers ( Medema et al., 1993; Kinzler and Vogelstein, 1996; Hanahan and Weinberg, 2000). This connection between cancer and stress resistance provides the theoretical foundation for the differential killing of cancer cells not by the identification of drugs that specifically kill malignant cells, but by the activation of stress resistance in normal cells (differential stress resistance section, DSR) and the treatment with chemotherapy ( Table 2). DSR is based on the hypothesis that in response to fasting, normal cells, independently of the cell type, will enter an alternate state characterized by reduced or lack of cell division, a switch to the utilization of the metabolites generated from the breakdown of fats, proteins and organelles (autophagy) described earlier, and resistance to multiple stresses ( Longo et al., 1997; Longo and Finch, 2003a; Raffaghello et al., 2008). The inability of cancer cells to respond to anti-growth signals or to grow in the absence of growth factors is a well-established hallmark of cancer ( Hanahan and Weinberg, 2000; Luo et al., 2009). More specifically, self sufficiency in growth signals is enabled by gain-of-function mutations in oncogenes (for example, Ras, Akt, mTOR and so on) that grant constitutive activation of proliferation pathways regardless of conditions. On the contrary, insensitivity to growth inhibitory signals is due to loss-of-function mutations in tumor-suppressor genes (for example, Rb, p53, PTEN and so on), allowing cancer cells to disregard anti-proliferation signals ( Hanahan and Weinberg, 2000; Vogelstein and Kinzler, 2004) and therefore also disregard the fasting-induced signals.

Table 2 Fasting protects against chemotherapy toxicity, in part by reducing IGF-I levels

Thus an effect of fasting on the growth of normal but not of cancer cells alone provides a method to preferentially target malignant cells with chemotherapy ( Raffaghello et al., 2008). However, this effect could be greatly enhanced by increasing stress resistance and activating a number of cell detoxification systems in both dividing and non-dividing cells. In fact, protection against stress in yeast mutants lacking RAS2 and SCH9 that are also starved increases 1000-fold or more compared with the approximately 10-fold increase in protection provided by fasting alone ( Raffaghello et al., 2008). Because, the inactivation of pro-growth pathways, particularly multiple pathways activated by glucose and amino acids, can increase stress resistance in both yeast and mammalian cells, the expression of constitutively or partially active oncoproteins present in the great majority of tumors is expected to prevent the protective effect of fasting regardless of the type of cancer or oncogene. Furthermore, cancer cells have been known for decades to rely more on glycolysis than on oxidative phosphorylation (Warburg effect), raising the possibility that the fasting-based enrichment of ketone bodies may increase their sensitivity.

The Warburg effect does not only apply to cancer cells, but also to rapidly dividing normal cells such as lymphocytes, thymocytes and enterocytes ( Newsholme et al., 1985). Although oxidative phosphorylation is far superior to glycolysis in terms of ATP production, glycolysis provides biosynthetic precursors that are essential to rapidly dividing cells. For instance, during glycolysis, glucose-6-phosphate can be directed to the pentose shunt pathway, providing reducing power and substrate for nucleotide synthesis, and glycerol can be processed into phospholipids that contribute to the cell wall ( Alberts et al., 2002). Increased glucose metabolism also allows cancer cells to restrict cytochrome c-mediated apoptosis, further favoring tumor cell survival ( Vaughn and Deshmukh, 2008). The Warburg effect may encourage apoptosis evasion by also decreased respiration. It has recently been shown, using yeast as a model organism, that respiration during seeding and development of a cell population triggers apoptosis, suggesting that decreased respiration may contribute to tumorigenesis ( Ruckenstuhl et al., 2009).

A major concern regarding the effect of fasting in improving cancer treatment is the possibility that it may also protect malignant cells. However, a number of studies in simple model organisms, mammalian cells and mice indicate that oncogenes can render malignant cells unresponsive to fasting, therefore allowing fasting to not interfere with therapeutic efficacy in the great majority of cancer types. As mentioned above, in yeast, the combination of starvation (switch from glucose medium to water at day 1) with the deletion of SCH9/ S6K or both SCH9/ S6K and RAS2 increased resistance to treatment with hydrogen peroxide or menadione a 1000-fold, compared with that of cells expressing the constitutively active oncogene homolog RAS2 val19 or cells lacking SCH9/S6K (sch9/s6kΔ) but expressing RAS2 val19 (sch9/ s6kΔRAS2 val19) ( Raffaghello et al., 2008). In fact, the expression of the oncogene-like RAS2 val19 can not only reverse the protective effects of starvation and mutations, but also reduce the resistance of cells compared with wild-type cells, raising the possibility that fasting may have a sensitizing effect on cancer cells. In mice, using a metastatic mouse model of neuroblastoma, induced by intravenous injection of NXS2 cells, fasting effectively protected the mouse without interfering with chemotherapy efficacy, suggesting that it did not protect these cancer cells ( Raffaghello et al., 2008). In this study, tumor-bearing mice were fasted for 48 h followed by a single administration of high-dose chemotherapy, which successfully improved survival limited by both drug toxicity and metastases.

Analogously to the activation of yeast Sch9 and Ras by amino acids and glucose, the mammalian IGF-I receptor activates PI3K/Akt/PKB and Ras, and regulates glucose metabolism and cellular proliferation ( Kandel and Hay, 1999). PI3K, which is frequently found mutated in human cancers ( Yuan and Cantley, 2008), regulates growth and glucose metabolism in part via its downstream effector AKT ( Vander Heiden et al., 2009). Notably, in normal cells, fasting can reduce PI3K signaling ( Xie et al., 2007), leading to the protection of the cell. mTOR is another well-established master regulator, which integrates three major components-growth factors, nutrients and cellular energy level (ATP)-to regulate cellular growth and metabolism. Therefore, whereas reduced glucose can protect normal cells ( Raffaghello et al., 2008) it may be detrimental to the survival of malignant cells.

Reduced IGF-I levels mediate in part fasting-dependent DSR

As mentioned above, fasting causes a 70% decrease in circulating IGF-I levels, and restoring its levels during fasting reverses the protection against doxorubicin in mice ( Lee et al., 2010). The effect of reduced IGF-I on protection against chemotherapy toxicity was also studied by using transgenic mice with a conditional liver-specific igf-1 gene deletion (LID), which results in a 70-80% reduction in circulating IGF-I levels, analogously to that caused by fasting. LID mice showed enhanced protection to commonly used chemotherapy drugs cyclophosphamide, doxorubicin and 5-FU, although they were not protected against the topoisomerase inhibitor etoposide. Reducing IGF-I signaling may provide dual benefits by protecting the organism and reducing tumor progression. In fact a recent study demonstrated the central role of IGF-IR in tumor progression and regression ( Jones et al., 2010) and at least 12 different IGF-IR targeting compounds, including small antagonistic molecules and antibodies, have entered clinical trials ( Gualberto and Pollak, 2009).

Fasting in clinical applications

Historically, fasting was performed for both medical and religious purposes ( Kerndt et al., 1982; Michalsen et al., 2005; Johnstone, 2007). Much has also been learned about the effects of fasting from data on the victims of famine and war ( Scrimshaw, 1987; Kalm and Semba, 2005), and also data from subjects fasting voluntarily for 40 days or longer ( Kerndt et al., 1982). Beyond its traditional practice, fasting has been demonstrated to have clinical benefits. Notably, clinical studies have shown that water-only fasting for 10-14 days significantly improved hypertension by reducing systolic blood pressure points more than two-fold compared with that of a combined vegan, low-fat, low-salt diet and exercise ( Goldhamer et al., 2001; Goldhamer, 2002). Moreover, the safety of fasting in patients with chronic disease has been studied in a large cohort study with over 2000 participants ( Michalsen et al., 2005). In this study, the authors determined that fasting (350kcal/day) was safe and considered by many of the participating subjects to be beneficial to their chronic disease ( Michalsen et al., 2005).

In a recent report, 10 patients with a variety of malignancies voluntarily fasted for up to 180 h in combination with chemotherapy, and reported a reduction in common chemotherapy-associated side-effects such as vomiting, diarrhea, fatigue and weakness ( Safdie et al., 2009) ( Table 2). Notably, in the cases where cancer progression could be followed, there was no evidence that fasting protected tumors or interfered with chemotherapy efficacy. A controlled randomized clinical trial testing the effect of fasting on cancer treatment underway at the University of Southern California Norris Cancer Center is expected to provide more conclusive clinical data on the effect of fasting on chemotherapy toxicity and efficacy.

Conclusion and discussions

According to the American Cancer Society, cancer patients receiving chemotherapy should increase calorie and protein intake ( Doyle et al., 2006). Contrary to this dogma, many studies suggest that a 20-40% reduction in calorie intake protects the host against toxins and retards the growth of tumors ( Moreschi, 1909; Tannenbaum, 1945; Hursting et al., 1994, 2001, 2003; Fontana et al., 2001, 2006; Harper et al., 2006; Bonorden et al., 2009; Colman et al., 2009; Longo and Fontana, 2010). However, this has never been translated into clinical applications because the effects are limited, as reduced calorie intake unavoidably causes weight loss, and because it was not clear that DR could not also protect cancer cells from chemotherapy. By contrast, based on the DSR studies and on clinical data, fasting for a limited period can have a potent protective effect on the host and possibly detrimental effects on a variety of tumors. However, fasting still poses a challenge to patients, which calls for an urgent need of substitution diets or targeted drugs that can mimic fasting. Experimental evidence from aging research suggests that diets with specific deficiencies, especially essential amino acids, may provide increased stress resistance and lifespan ( Richie et al., 1994; Takenaka et al., 2000; Harper et al., 2006). Although, it is unlikely that the vast effects caused by fasting can be obtained with specific deficiencies, it will be important to determine whether limitations of specific nutrients will be sufficient to promote some of the effects of fasting. Furthermore, because cancer depends on certain nutrients, there is a large potential for the combination of dietary interventions and chemotherapy or other non-toxic cancer therapies for the enhancement of cancer treatment. In addition, as discussed in this study, exploring drug targets based on the IGF-I and related systems may also identify fasting-mimetics that provide DSR. Interventions that could provide a differential protection of host and cancer cells in the 1000-fold differential protection range observed in yeast cell lacking or expressing an oncogene analog, could have paradigm shifting effects in cancer treatment.

References

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Affiliations

Department of Biological Sciences and Norris Cancer Center, Andrus Gerontology Center, University of Southern California, Los Angeles, CA, USA

C Lee & V D Longo

Corresponding author

Correspondence to V D Longo.

Ethics declarations

Competing interests

Valter Longo founded L-Nutra, which develops diets for cancer patients.

About this article

Cite this article

Lee, C., Longo, V. Fasting vs dietary restriction in cellular protection and cancer treatment: from model organisms to patients. Oncogene 30, 3305-3316 (2011). https://doi.org/10.1038/onc.2011.91
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Keywords

fasting

dietary restriction

chemotherapy

differential stress resistance

starvation

Further reading

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Fasting vs dietary restriction in cellular protection and cancer treatment: from model organisms to patients

# data[].attributes.attachment_link.description
The dietary recommendation for cancer patients receiving chemotherapy, as described by the American Cancer Society, is to increase calorie and protein intake. Yet, in simple organisms, mice, and humans, fasting-no calorie intake-induces a wide range of changes associated with cellular protection, which would be difficult to achieve even with a cocktail of potent drugs.

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Plant-based gel to fast-track growth of 'mini-organs' to improve cancer treatment

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Plant-based gel to fast-track growth of 'mini-organs' to improve cancer treatment

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https://www.sciencedaily.com/releases/2020/11/201125091525.htm

This (nanocellulose) gel costs a fraction of the price compared to the ones' used currently and they have the ability to mimic conditions in the human body. It also has the potential to improve drug-screening for infectious diseases, like COVID-19 and other metabolic diseases such as obesity and cancer.

1. Are there any ethical issues or possible side effects?
2. Does the properties of this gel provide long-term relief/rehabilitation or is it short-term?

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A new device can produce electricity using shadows - Axel

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A new device can produce electricity using shadows - Axel

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A research team from the University of Singapore created a device that can produce electricity using the contrast between light and shadow. A higher contrast produces a higher amount of energy. It can provide ways to make use of shadows and generate power in places that solar panels or other conventional means of producing power could not be used. These include indoors and in a heavily shaded forest or city of skyscrapers.

How could this tech be integrated efficiently in our society?
Could this become as popular and accessible as solar panels?

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Someday, shadows and light could team up to provide power.

A new device exploits the contrast between bright spots and shade to create a current that can power small electronics. "We can harvest energy anywhere on Earth, not just open spaces," says Swee Ching Tan, a materials scientist at the National University of Singapore.

Tan and his team created the device, called a shadow-effect energy generator, by placing a superthin coating of gold on silicon, a typical solar cell material. Like in a solar cell, light shining on silicon energizes its electrons. With the gold layer, the shadow-effect energy generator produces an electric current when part of the device lies in shadow.

The excited electrons jump from the silicon to the gold. With part of the device shaded, the voltage of the illuminated metal increases relative to the dark area and electrons in the generator flow from high to low voltage. Sending them through an external circuit creates a current that can power a gadget, Tan's team reports April 15 in Energy & Environmental Science.

With eight generators, the team ran an electronic watch in low light. The devices can also serve as sensors. When a remote-controlled car passed by, its shadow fell on a generator, creating the electricity to light up an LED.

The greater the contrast between light and dark, the more energy the generator provides. So the team is working to boost the device's performance by borrowing strategies from solar cells for gathering light. Increasing the light these generators absorb would allow them to better exploit shadows.

Someday, these generators might produce energy in the shadowy spots in a solar array, between skyscrapers or even indoors. "A lot of people think that shadows are useless," Tan says. But "anything can be useful, even shadows."

Questions or comments on this article? E-mail us at feedback@sciencenews.org

A version of this article appears in the July 4, 2020 issue of Science News.

Carolyn Wilke is a freelance science journalist and former staff writer at Science News for Students. She has a Ph.D. in environmental engineering from Northwestern University.

# data[].attributes.attachment_link.title
A new device can produce electricity using shadows

# data[].attributes.attachment_link.description
Someday, shadows and light could team up to provide power. A new device exploits the contrast between bright spots and shade to create a current that can power small electronics. "We can harvest energy anywhere on Earth, not just open spaces," says Swee Ching Tan, a materials scientist at the National University of Singapore.

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Farming on Mars will be a lot harder than ‘The Martian’ made it seem

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Farming on Mars will be a lot harder than ‘The Martian’ made it seem

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In the article, it informs the audience on the difficulty of farming in mars. it explains the how earth soil has microbes and other organic matter that helps plants grow while mars soil is basically crushed rock. the team suspected the difficulty of farming was due to the soils high pH which was 9.5, when researchers treated it with sulfuric acid to lower the pH to 7.2 the plants lasted an extra week but ultimately died.

1 could you artificially implant microbes and other organic matter to help plants grow.

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The article informs the audience about how a red giant star has gone dark and the possible implications. I think that it's interesting because the darkening of Betelgeuse could mean a supernova is approaching, or it could give us the clue to life.

1.If a dust cloud doesn't explain why the star is going darker, then what does?

2.If the star isn't going to die in the next 2000 years, why is it darkening?

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Phosphine gas found in Venus' atmosphere may be a possible sign of life 

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Phosphine gas found in Venus' atmosphere may be a possible sign of life 

# data[].attributes.body
This article explains why the discovery of phosphine in Venus' atmosphere is significant. I find this interesting because while there is very little chance that this observation means anything, it would be cool it there is microbial life living on Venus because it would prove that life beginning on other planets is possible. LB.

1.  If basic life has formed on Venus how is is surviving the harsh climate on the surface and atmosphere of the planet.

2. Is it possible that life was unknowingly sent to Venus on one of the probes launched from earth.

https://www.sciencenews.org/article/phosphine-gas-found-venus-atmosphere-possible-sign-life

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Two distinctly different liquid states of water

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Two distinctly different liquid states of water

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https://www.sciencedaily.com/releases/2020/11/201119141756.htm

Most people seem to think of water as just that, water, so if there is a difference in types of water, that could be interesting.

1. What are the differences between the states
2. What causes these change in properties between them

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Dog ticks may get more of a taste for human blood as the climate changes

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Dog ticks may get more of a taste for human blood as the climate changes

# data[].attributes.body
In  this article, it informs the audience of how when the temperature increases to around 38 degrees Celsius, brown dog ticks were more attracted to humans than dogs. With this discovery, concerns arise around the increase spread of a disease. The diseases is the Rocky Mountain Spotted Fever which is a pathogen that can be found in ticks. Unfortunately, this pathogen can be lethal to humans, if not treated correctly or immediately.

Questions
- What behavioural adaptations have occurred in ticks that cause them to be attracted to humans in hotter weather?
- Does the attraction to humans change between the different species of ticks?

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Climate change could turn some dog ticks into suckers for humans instead of canines.

At temperatures around 38° Celsius (100° Fahrenheit), some brown dog ticks were more attracted to people than to dogs, experiments show. The ticks can carry the pathogen that causes deadly Rocky Mountain spotted fever. The finding suggests that a warmer climate could lead to greater spread of the disease from ticks to humans, researchers reported November 16 at the annual meeting of the American Society of Tropical Medicine and Hygiene.

"We can expect more frequent and larger disease outbreaks of Rocky Mountain spotted fever when hot weather occurs, and when we get hot weather more often," says Laura Backus, a researcher at the University of California, Davis School of Veterinary Medicine. Patients with Rocky Mountain spotted fever can die if they don't receive antibiotic treatment within five days. Around 5 to 10 percent of people infected succumb to the disease.

Previous research in Europe had suggested that ticks are more aggressive toward people in hot weather. To find out whether brown dog ticks' preference of host depends on temperature, Backus and her colleagues captured babies and adults of two genetically distinct groups, or lineages, of the species Rhipicephalus sanguineus. One lineage hailed from a hot region in Arizona, and was considered a tropical tick. The other lineage, from Oklahoma, tolerates colder weather and is considered temperate.

The scientists compared the ticks' behavior at a room temperature of 23° C (74° F) and at a sweltering 38° C. In 10 separate trials at each temperature, the scientists placed around 20 ticks from both lineages and age groups into the center of a plastic tube and gave them the option of moving toward a either a human or a dog.

Normally, the tick prefers dogs to humans. But at the higher temperature, the adult tropical ticks showed a preference for the human. More than twice as many of the ticks moved toward the human at the hotter temperature compared with at room temperature. The temperature shift did not have a significant effect on the temperate ticks or the nymphs of either lineage.

Don Preisler/UC Davis School of Veterinary Medicine

It is unclear why the adult tropical ticks switched their preference at high temperature. It may have something to do with the way they sense their hosts. "It is possible that their chemical receptors on their bodies are activated differently at high temperatures, but it's still unclear," Backus adds.

In the last two decades, the United States has seen a steady rise in tick-borne diseases ( SN: 11/15/18). In 2000, there were 495 cases of spotted fever rickettsiosis, a category that includes Rocky Mountain spotted fever, the U.S. Centers for Disease Control and Prevention reports. Now, 4,000 to 6,000 tickborne spotted fevers are reported in the United States each year.

Different kinds of ticks can carry the bacteria that causes Rocky Mountain spotted fever. But the brown dog tick is responsible for the spread in the southwestern United States.

"The finding is very exciting, as it demonstrates the behavioral difference between the two lineages," says Kathleen Walker, an entomologist at the University of Arizona in Tucson who was not associated with the study. More tropical ticks, she adds, are moving to the north as temperatures rise due to global warming.

Backus says that her team would like to study brown dog ticks from more regions in the future, a step toward having a bigger dataset to look for patterns. "And if they prefer humans at high temperatures, as this study finds, then that helps in understanding why we are seeing more Rocky Mountain spotted fever outbreaks," she says.

Questions or comments on this article? E-mail us at feedback@sciencenews.org

Aayushi Pratap is a fall 2020 science writing intern. She has a master's degree in science and health journalism from Columbia University, as well as degrees in biochemistry and zoology. Previously she worked as a health reporter with the Hindustan Times in Mumbai, India, covering public health.

# data[].attributes.attachment_link.title
Dog ticks may get more of a taste for human blood as the climate changes

# data[].attributes.attachment_link.description
Climate change could turn some dog ticks into suckers for humans instead of canines. At temperatures around 38° Celsius (100° Fahrenheit), some brown dog ticks were more attracted to people than to dogs, experiments show. The ticks can carry the pathogen that causes deadly Rocky Mountain spotted fever.

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LK
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A group of researches found a material with the ability to act as a superconductor within room temperature. A superconductor is able to conduct electricity with no resistance meaning that the whole efficiency of electronics is greatly increased. The implications of this discovery could result in a new electronics boom, allowing for great advances in medical fields & telecommunications initially.

How can the improved efficiency of superconductors help the problems of the 21 century?

What could a future with superconductors look like?

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Astronomers spotted colliding neutron stars that may have formed a magnetar

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Astronomers spotted colliding neutron stars that may have formed a magnetar

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The article is about the merging of two neutron stars colliding to form a magnetar. I find this interesting because neutron stars are some of the most extreme objects in the universe. The two neutron stars colliding may have caused a kilinova explosion, which have the brightness of up 1/10 of a supernova explosion.

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Find some new research from this year that you think is interesting. Create a post (click the plus sign in the bottom right hand corner of this page) sharing this research.

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