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Grammar Journal Assignment #10: Noun Clauses

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Grammar Journal Assignment #10: Noun Clauses

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Noun Clauses: These clauses are the direct object of the verb, the subject or the adjective or noun complement and are dependant clauses. Usually begin with that, if, whether, who, what, why, when, where, how, which, and followed by a subject and a verb. These clauses modify independent main clauses.

Example: "I don´t know what happened at the game."

Example 1 found in authentic material: “It is important that we recognize Bruce for all he has done and will continue to do,” Gov. Phil Murphy says."

Reflection: This clause can follow verbs of necessity and advise, and also can be subject complements or adjective and noun complements of the main sentence.

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Bruce Springsteen Day to Take Place in New Jersey in September

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“It is important that we recognize Bruce for all he has done and will continue to do,” Gov. Phil Murphy says

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Grammar Journal Assignment #9: Adverb Clauses 

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Grammar Journal Assignment #9: Adverb Clauses 

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Adverb Clauses: Adverb clauses modify independent main clauses. They can tell when, why, where, or how and are dependent clauses with their own subject and verb. "subordinator (by the time, because and wherever, since, as, because, while, do the fact that)+ "," if the main clause is after the adverb clause."

Example: "Since he missed the bus, he was late for the interview."

Example 1 found in authentic material: “USC coach Lincoln Riley had compiled a history of winning big at the collegiate level by the time he arrived as the head man in Los Angeles, and his first year with the Trojans proved to be no different."

Reflection: It is essential to recognize these clauses by the subordinator, the structure of the sentences if is independent or dependant, and understand that this clause shows time, gives reasons, shows concession or contrast, shows a place or a purpose.

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USC coach Lincoln Riley had compiled a history of winning big at the collegiate level by the time he arrived as the head man in Los Angeles, and his first year with the Trojans proved to be no different. After a miserable 4-8 campaign in 2021, USC went 11-3 in Riley's debut -- its best campaign since 2017 -- with quarterback Caleb Williams winning the Heisman Trophy along the way.

For all the success, however, USC had plenty of growing pains, especially on defense. The Trojans allowed 126 points across their three losses, 16 of which went unanswered in fewer than four minutes in the Cotton Bowl against Tulane. Few coaches get a second season with a reigning Heisman Trophy winner, so the Trojans have to get up to speed quickly on the defensive side of the ball.

Here's everything you need to know about the Trojans' 2023 spring football game, which takes place at LA Memorial Coliseum on Saturday.

How to watch 2023 USC spring game live

Date: Saturday, April 15 | Time: 3 p.m. ET
Location: LA Memorial Coliseum -- Los Angeles, California
TV Channel: Pac-12 Network | Live stream: fuboTV ( try for free)

2023 USC spring game storylines

1. Integrating defensive pieces: The Trojans put together a miserable defensive campaign, and then promptly lost top defenders Mekhi Blackmon and Tuli Tuipulotu after the season. Defensive coordinator Alex Grinch hit the portal hard over the offseason to try to grow the defensive line, which will be the unit to watch in the spring game as the Trojans integrate former blue-chip recruit Anthony Lucas, Purdue transfer Jack Sullivan and Arizona transfer Kyon Barrs. While the attention will remain on offense, the growth of the defense will determine USC's fate in 2023.

2. Finding new skill pieces: Williams is back to take snaps, but both his top rusher and receiver are gone as Travis Dye and Jordan Addison begin their NFL journeys. The offense took a step back when Addison went out, and Riley looked to the portal to bring in key contributors. Among them are 1,100-yard receiver Dorian Singer from Arizona and South Carolina transfer running back MarShawn Lloyd. At receiver, superstar freshmen Zachariah Branch and Makai Lemon will also compete with Mario Williams, Tahj Washington and more for touches.

3. The future at QB: Williams returns to campus as the most convincing QB1 in college football, but there isn't much experience behind him. Sophomore Miller Moss has thrown 27 passes over the past two seasons with two touchdowns and no picks. However, many think consensus five-star recruit Malachi Nelson is the future at the position after being hand-selected by Riley as a high school recruit. Both Moss and Nelson should get plenty of action in the spring game as the staff tries to keep Williams healthy for a highly anticipated junior campaign.

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2023 USC football spring game live stream, watch online, TV channel, start time, storylines to follow

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USC coach Lincoln Riley had compiled a history of winning big at the collegiate level by the time he arrived as the head man in Los Angeles, and his first year with the Trojans proved to be no different.

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Grammar Journal Assignment #8: Adjective Clauses

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Grammar Journal Assignment #8: Adjective Clauses

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Adjective Clauses is a dependent clause that describes a noun. The structure usually is "relative pronoun+ modify or describe a subject or object noun from the main sentence."

Example: "Maria, who is the best in the class, got B+ in the grammar exam."

Example 1 found in authentic material: “Wyoming police have identified two men who were fatally shot Friday, March 31, outside of a house on Buchanan Avenue SW.e."

Reflection: It is important to recognize when the adjective is describing the subject or object of the main sentence and if it is necessary or not to add commas if it is not essential information.

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UPDATE: Information in this story has been updated to show that Louis Gonzales, not Louis Ruiz, was identified as one of two men found dead in Wyoming. Police initially provided incorrect information.

KENT COUNTY, MI - Wyoming police have identified two men who were fatally shot Friday, March 31, outside of a house on Buchanan Avenue SW.

Andrew Gil, 25, and Louis Gonzales, 30, were found dead when police responded to a 7:34 a.m. call to 911.

Gil was found inside a vehicle parked in the driveway of a house in the 3000 block of Buchanan, between 28th and 32nd streets. He lived at the house, according to online records.

Gonzales' body was in the driveway near the car.

Related: 2 men found dead after shooting at Wyoming home

Police recovered a handgun at the scene. Police continue to investigate circumstances surrounding the deaths but said it appears that there is not a threat to the public.

Police asked anyone with information to contact investigators at 616-530-7300 or Silent Observer at 616-774-2345 or www.silentobserver.org
Read more: No-prescription Narcan will save more Michigan lives, advocates say Tornado forecast inches into Michigan, watching evening squall line These 100 photos highlight 10th anniversary of Grand Rapids Griffins' Calder Cup championship

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Police identify 2 men who were fatally shot outside Wyoming home

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UPDATE: Information in this story has been updated to show that Louis Gonzales, not Louis Ruiz, was identified as one of two men found dead in Wyoming. Police initially provided incorrect information. KENT COUNTY, MI - Wyoming police have identified two men who were fatally shot Friday, March 31, outside of a house on Buchanan Avenue SW.

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Perfect Gerund can be used to show the difference in time between two events, one happened before the other and the perfect gerund happened before the time of the main verb.  The structure is "having+ past participle."

Example: "She accepted having eaten all the cookies."

Example 1 found in authentic material: “Inspectors rated it inadequate having found "widespread and significant shortfalls" in care."

Reflection: It is important to recognize the perfect gerund in a sentence where the time is not clear, and identify the order of the activities.

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The firm's operational director, Vanessa Cutler, acknowledged CQC inspectors had visited after receiving "several anonymous complaints which we now believe to have been [from] staff" who "hadn't been listened to ... and were refusing to work with the management team", leading to a reliance on agency workers whose training and documentation had not been checked thoroughly.

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Newcastle care home whistleblowers alert CQC to failings

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The firm's operational director, Vanessa Cutler, acknowledged CQC inspectors had visited after receiving "several anonymous complaints which we now believe to have been [from] staff" who "hadn't been listened to ... and were refusing to work with the management team", leading to a reliance on agency workers whose training and documentation had not been checked thoroughly.

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Modals can be used to give advice  or opinions about a current situation, to talk about necessity or something that is required, and also to indicate prohibition and obligation to do something.  The structure is the "modal + base form of the verb."

Example: " You shouldn´t quit your job yet."

Example 1 found in authentic material: “Biden must follow Roosevelt’s ‘arsenal of democracy’ example."

Example 2 found in authentic material: "Some U.S. military officials have suggested that Ukraine should slow the rate at which it fires artillery shells, or pick its targets more selectively."

Reflection: Modals are a way to express weaker or stronger forms of telling something, and are used in different scenarios to advise, prohibit, obligate, or show necessity.

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Ukrainian soldiers prepare to fire a self-propelled howitzer shell toward Russian forces near Bakhmut, Ukraine, on Sunday. (AP)

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Russia's invasion of Ukraine did not catch the West's intelligence agencies unaware. But no one in Washington or Europe anticipated the scale at which they would need to provide Kyiv with arms and munitions. That's an increasing challenge for NATO and other countries rightly determined to prevent a Russian victory, and the dire consequences for the United States and its allies that would follow. It needs to be addressed swiftly.

In a ground war that in some ways has come to resemble World War I - with thousands of artillery rounds fired daily against deeply dug-in armies - Ukrainian forces are now at risk of running low on key munitions. They are firing shells faster than supplier nations are producing them. There are other historic echoes. Just as President Franklin D. Roosevelt called on Americans to rally behind the country's European allies as the "arsenal of democracy" in 1940, a year before Pearl Harbor, President Biden will be tested and judged by his own success in making a similar case for this country to step up by applying its military and industrial might.

The most pressing need in Ukraine is the supply of 155mm howitzer shells, which in recent months have become the main munition holding Russia at bay. The United States has supplied more than 1 million to Ukraine since the war's outset, according to the Pentagon. Ukrainian artillery units have been firing them at a rate of roughly 3,000 daily - perhaps one-third the number of rounds screaming back at them from the Russian side. The math is unforgiving. Not only is Ukraine's inventory dwindling, but the U.S. prewar production of the shells, fewer than 15,000 per month, is scarcely enough to sustain Ukraine for five days.

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To its credit, the Biden administration is gearing up for a sixfold increase in monthly production of the shells, and sharply accelerating the manufacture of other materiel. European countries, too, are rushing to furnish Ukraine with more shells. That will take time, however, not least because defense-procurement bureaucracies, in this country and other major industrialized democracies, have been calibrated mainly for peacetime since the Cold War. Germany in particular, which has tried to surge its defense spending, faces long-standing problems with red tape and inefficiencies that have impeded arms production.
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Also on the Editorial Board's agenda

Biden has a new border plan.

The United States should keep the pressure on Nicaragua.

America's fight against inflation isn't over.

The Taliban has doubled down on the repression of women.

The world's ice is melting quickly.

The Department of Homeland Security has provided details of a plan to prevent a migrant surge along the southern border. The administration would presumptively deny asylum to migrants who failed to seek it in a third country en route - unless they face "an extreme and imminent threat" of rape, kidnapping, torture or murder. Critics allege that this is akin to an illegal Trump-era policy. In fact, President Biden is acting lawfully in response to what was fast becoming an unmanageable flow at the border. Read our most recent editorial on the U.S. asylum system.

Some 222 Nicaraguan political prisoners left that Central American country for the United States in February. President Daniel Ortega released and sent them into exile in a single motion. Nevertheless, it appears that Mr. Ortega let them go under pressure from economic sanctions the United States imposed on his regime when he launched a wave of repression in 2018. The Biden administration should keep the pressure on. Read recent editorials about the situation in Nicaragua.

Inflation remains stubbornly high at 6.4 percent in January. The Federal Reserve's job is not done in this fight. More interest rate hikes are needed. Read a recent editorial about inflation and the Fed.

Afghanistan's rulers had promised that barring women from universities was only temporary. But private universities got a letter on Jan. 28 warning them that women are prohibited from taking university entrance examinations. Afghanistan has 140 private universities across 24 provinces, with around 200,000 students. Out of those, some 60,000 to 70,000 are women, the AP reports. Read a recent editorial on women's rights in Afghanistan.

A new study finds that half the world's mountain glaciers and ice caps will melt even if global warming is restrained to 1.5 degrees Celsius - which it won't be. This would feed sea-level rise and imperil water sources for hundreds of millions. Read a recent editorial on how to cope with rising seas, and another on the policies needed to fight climate change.

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The need to provide more weapons systems to Ukraine is equally urgent. Yet the problem, depending on the system, tends to be different. Take, for instance, the High Mobility Artillery Rocket System (HIMARS), the precision multiple rocket launcher that has been used to deadly effect against Russian ammunition dumps, command posts and other targets. Hundreds of HIMARS are in U.S. and other NATO countries' inventories, yet just 20 or so have been sent so far to Ukraine. The Ukrainians have shown their ability to shift the battlefield momentum with HIMARS, and they have pleaded for more of them. Yet the Western allies have dragged their feet.

One reason is that Washington and its allies are reluctant to draw from stockpiles of the weapon, given the need to train their own forces on its use. War planners in the Pentagon are wary of eroding U.S. military readiness in the event of another conceivable ground war - on the Korean Peninsula, for example, or involving NATO's Baltic allies. That same reluctance is at play with other weapons. The result is a gap between the West's supportive rhetoric on equipping Ukraine against Russian President Vladimir Putin's ruinous invasion, and the pace of actual deliveries of arms and ammunition, which is slower than Kyiv needs to push back Russian forces.

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Some U.S. military officials have suggested that Ukraine should slow the rate at which it fires artillery shells, or pick its targets more selectively. That's an armchair general's risky prescription, overlooking the fact that Kyiv is already enormously outgunned and outmanned. It's worth remembering that Ukrainian forces have massively outperformed expectations. More than a year after an invasion that most outsiders believed would succeed within days, second-guessing Ukrainian tactics is the height of presumption as their citizens continue dying on the battlefield against a country with triple Ukraine's population and an economy nearly 10 times its size.

The burden is rightly on the West to ramp up production and shipment of the weapons and munitions Ukraine needs. And there are steps Washington and its allies can take to achieve that, beyond the sharp increases in defense spending to meet what seems likely to be a long-term commitment to Kyiv's security, along with other growing threats to U.S. interests.

One sensible move would be to send Ukraine some weapons currently in the arsenals of National Guard units in individual states. Granted, that has the potential to erode their training capacity and combat readiness in the short term. Until the stockpiles could be replenished, it is likely some governors would complain.

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In other cases, the administration would be wise to undertake a clear-eyed analysis of the strategic consequences of framing these decisions too narrowly. According to Mark Cancian of the Center for Strategic and International Studies, the Pentagon has shipped about 40 percent of the U.S. stockpile of some 20,000 Javelin antitank missiles, leaving a hole in our inventory that will take several years to fill at the current production level. It is understandable that Pentagon planners are reluctant to deplete their own supplies further. Yet if Ukraine's planned spring offensive fails for lack of Javelins or other weapons that Washington could have provided in greater numbers,the Biden administration will regret its hesitation to take unorthodox steps.

It's critical that the administration perceive those interests clearly and explain them compellingly to what recent polls suggest is an increasingly skeptical American public. Turning back Russian aggression is not only important for our European allies' security but also to maintain a basic principle of civilized international relations: that one state cannot invade and subjugate another that has posed no threat. It is also crucial to transmit the message to China, North Korea and other would-be aggressors that the United States will stand fast in defense of its own interests and other democracies.

The Post's View | About the Editorial Board

Editorials represent the views of The Post as an institution, as determined through debate among members of the Editorial Board, based in the Opinions section and separate from the newsroom.

Members of the Editorial Board and areas of focus: Opinion Editor David Shipley;Deputy Opinion Editor Karen Tumulty; Associate Opinion Editor Stephen Stromberg (national politics and policy, legal affairs, energy, the environment, health care); Lee Hockstader (European affairs); David E. Hoffman (global public health); James Hohmann (domestic policy and electoral politics, including the White House, Congress and governors); Charles Lane (foreign affairs, national security, international economics); Heather Long (economics); Associate Editor Ruth Marcus; and Molly Roberts (technology and society).

The Editorial Board on the war in Ukraine

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Opinion | Biden must follow Roosevelt's 'arsenal of democracy' example

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Listen 6 min CommentArticle Share Russia's invasion of Ukraine did not catch the West's intelligence agencies unaware. But no one in Washington or Europe anticipated the scale at which they would need to provide Kyiv with arms and munitions.

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Investigation of the effective atomic number dependency on kinetic energy using collision stopping powers for electrons, protons, alpha, and carbon particles - Scientific Reports

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Grammar Journal Assignment #5: Passive tenses 

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Grammar Journal Assignment #5: Passive tenses 

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Passive sentences are mainly used in formal and scientific writing and when who or what causes the action is unknown or unimportant. The structure of passive tense is the verb 'to be' into whatever tense is needed and then adding the past participle.

Example: ‘My watch was stolen.’

Example found in autentic material: “The kinetic energy region of 10 keV–20 MeV is considered for electrons, and the proton particles are studied in the energy kinetic energy range of 60 MeV to 200 MeV.”

Reflection: The use of passive tense is exceptional. We usually use action tense to speak and write, but when the subject is not relevant we must use passive tense.

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Introduction

The effective atomic number can be applied to characterize the radiological properties of materials. In the different fields such as radiotherapy and dosimetry the radiological properties of materials can be applied in estimating absorbed dose, buildup factor, and shield design. One of the most effective parameters that define the radiation features of a material is the atomic number. In the event of photons in specific energy, the value of the delivered energy is calculated using the mass absorption coefficient1. This parameter depends on the medium atomic number. Also, the amount of the transferred energy of the charged particles is calculated using their stopping power. Thus, in known energies, this parameter varies depending on the medium's atomic number2. When the medium is a compound, the atomic number will be defined as the effective atomic number3. There have been many studies for calculating the effective atomic number for various materials. Most of these calculations were based on averaging and interpolating the available data4,5.

Toward calculating Z eff, the charged particle stopping power in a specific medium was carried out of the NIST database. The effective atomic number (Z eff) attributes to the target medium and the beam particles. Moreover, it gives information on the radiation interaction characteristics in a specific energy range. In fact, the intrinsic atoms can be substituted for a given molecule with exactly the same number of compatible atoms2. The replaced molecules are considered to contain a Z eff number of electrons. Besides, the electron density is related to the interaction zones and correspondingly relates to the effective atomic number, which must be regarded during opting materials and dosimeters6.

Consequently, the most prominent characteristics that describe the interaction of radiation with different materials are effective atomic number (Z eff) and electron density (N e)7. In addition, these parameters are used to distinguish materials with the purpose that the most accurate results are obtained during a radiotherapy process. In other words, the most precise diagnostics only can be obtained when the materials are properly individualized8. Earlier methods for calculating Z eff were based on percent composition by mass of elements, mass attenuation coefficient, Auto Z eff code, and stopping power tables9,10,11,12.

The percent composition by mass of elements is not dependent on type and energy. While the mass attenuation coefficient calculations, which can be used only when determining the Z eff for photon, depend on energy. This refers to the physical concept that in various energies of the incident beam, the probability of the interactions between an element of the compound with photons will change accordingly. Regarding the dependency of types of interactions on the type of the element and energy of the photon, there is a possibility that in different energies, the atomic number also changes. Numerous researchers have studied effective atomic numbers for photons7,13,14,15,16. Meanwhile, quite a few have discussed Z eff for electron, alpha, proton, and carbon in different energies1,13,17. Kurudirek calculated the effective atomic number for some charged particles using the interpolation method of stopping powers1,3.

In the present work, Z eff of 19 materials relevant to dosimetry is calculated for total electron interactions in the wide kinetic energy range of 10 keV to 1 GeV. Because of the dependency of stopping power on some experimental parameters, in this paper, a direct method is used to calculate the effective atomic number. In this method, interpolations were not used, and for each compound, the effective atomic number can be calculated directly by its stopping power and average ionization and excitation energy.

The variation of Z eff through the entire kinetic energy region is also investigated. Moreover, the water, as well as tissue equivalence properties of the materials, is studied in the entire kinetic energy region. The effective atomic number was calculated for 19 materials equivalent to tissue, and dosimetry compounds used Bethe's formula18.

The determinations are done utilizing collision-stopping power. The kinetic energy region of 10 keV-20 MeV is considered for electrons, and the proton particles are studied in the energy kinetic energy range of 60 MeV to 200 MeV. Furthermore, Z eff calculated for the alpha particles with a kinetic energy of 9 MeV and carbon ions of 2 GeV.

Methods

Due to the significant importance of determining the body tissue's effective atomic number for charged particles, an attempt is made to study 19 tissue equivalent materials and dosimetry compounds, as shown in Table 1. Coulomb interaction was considered, and the Z eff was calculated in different kinetic energy ranges for electron, proton, alpha, and carbon ions. The effective atomic number for the mentioned particles was determined using the collisional stopping power equation and the stopping powers extracted from the NIST library. It must be indicated that, since the atomic number is not specified for compounds, Bethe's formula cannot be used directly for determining stopping power. As a result, the effective atomic number was determined based on the stopping power value and an unknown atomic number.

Assuming that all the atoms and their electrons behave independently from each other and all the kinetic energy only will be spent on ionization and excitation, in that case, the collisional stopping power of the electrons is calculated by Bethe's formula:

$$-\frac{dE}{dx} \left(\frac{MeV}{m}\right)=4\pi {{r}_{0}}^{2}{z}^{2}\frac{m{c}^{2}}{{\beta }^{2}} NZ\left\{\mathit{ln}\left(\frac{\beta \gamma \sqrt{\gamma -1}}{I}m {c}^{2}\right)+\frac{1}{2{\gamma }^{2}}\left[(\frac{{\left(\gamma -1\right)}^{2}}{8}+1-\left({\gamma }^{2}+2\gamma -1\right)ln2)\right]\right\}$$

where \(4\pi {{r}_{0}}^{2}={10}^{-24}{\mathrm{cm}}^{2}\), \({r}_{0}=\frac{{e}^{2}}{m{c}^{2}}=2.818*{10}^{-15}\mathrm{m}\), \(m{c}^{2}=0.511 \mathrm{MeV}\), \(m\) is the rest mass of an electron, \(Z\) is the atomic number of the medium, \(z\) is the particle charge, \(N\) is the atomic mass, \(I\) is the average ionization and excitation kinetic energy, \(\gamma = \frac{1}{\sqrt{1-{\beta }^{2}}}\) and \(\beta =\frac{v}{c }\), \(c=3*{10}^{8} \mathrm{m}/\mathrm{s}\).

Also, the collisional stopping power of ionization and excitation for heavy ions like \(\alpha \), \(t\), \(d\), and \(p\) is equal to:

$$-\frac{dE}{dx}(MeV/m)=4\pi {{r}_{0}}^{2}{z}^{2}\frac{m{c}^{2}}{{\beta }^{2}}NZ\left[\mathrm{ln}\left(\frac{2m{c}^{2}}{I}{\beta }^{2}{\gamma }^{2}\right)-{\beta }^{2}\right]$$

Since there are some assumptions in Bethe's formula, in high kinetic energy ranges, the values of stopping power calculated using this relation may differ from experimental data. Although the basis of ESTAR code calculations is Bethe's formula, it uses some experimental parameters such as density effect correction. So, this code's calculated values are closer to the experimental values. Therefore, the collisional stopping powers were calculated for different elements to select the appropriate kinetic energy range, utilizing Eq. ( 1). These values were compared with stopping powers gathered from the ESTAR database19. The valid kinetic energy range is selected as the range that relative difference between the calculated stopping power using Bethe's formula and the stopping power extracted from the NIST data library is less than 20%.

In pursuance of determining the effective atomic number by means of the collisional stopping power of the electrons, the values of \({\left(\frac{dE}{dx}\right)}\), were gathered from the ESTAR database, and the values for Z eff were determined using Eq. ( 3).

$$Z=\left(\frac{\left|\frac{dE}{dx}\right|}{ 4\pi {{r}_{0}}^{2}{z}^{2}\frac{m{c}^{2}}{{\beta }^{2}} N\left\{\mathit{ln}\left(\frac{\beta \gamma \sqrt{\gamma -1}}{I}m {c}^{2}\right)+\frac{1}{2{\gamma }^{2}}\left[(\frac{{\left(\gamma -1\right)}^{2}}{8}+1-\left({\gamma }^{2}+2\gamma -1\right)ln2)\right]\right\}}\right)$$

Also, to calculate the collisional stopping power for proton, alpha, and carbon, the same procedures were taken. As mentioned before, the collisional stopping power of the elements of each compound was obtained by Eq. ( 2).

Moreover, the data was extracted from ASTAR20, PSTAR21, and SRIM databases22. Final data were compared to each other, so those ranges of kinetic energy where the relative error of the results were less than 20% were introduced as valid kinetic energy range. Also, the values for Z eff were determined using Eq. ( 4).

$$Z=\left(\frac{\left|\frac{dE}{dx}\right| }{ 4\pi {{r}_{0}}^{2}{z}^{2}\frac{m{c}^{2}}{{\beta }^{2}}NZ\left[\mathit{ln}\left(\frac{2m{c}^{2}}{I}{\beta }^{2}{\gamma }^{2}\right)-{\beta }^{2}\right]}\right)$$

Results

Zeff of electron

The data from the ESTAR database and theoretical data of the collisional stopping power of electrons were determined and compared. The kinetic energy ranges where the percentage of the relative difference of the results is less than 20% are identified as valid kinetic energy ranges. The compounds with such features are set in Table 2. As can be seen, for the electron interaction, the percentage of the relative difference in low kinetic energy ranges is less than 20%.

According to Table 3 data, the effective atomic numbers for different compounds used as dosimeters or detectors are calculated for several specific energies in valid kinetic energy ranges. Since Eq. ( 1) is most important for electron interactions in low energies, the main focus is on these kinetic energy ranges.

As it is apparent, in low kinetic energy ranges, the effective atomic number is nearly equal to the total number of electrons owned by the compound. These results can be explained since they rely on collisional stopping power. While an electron transports a medium, it will have Coulomb interaction with all the electrons. As the interaction happens for all the electrons, the value of the effective atomic number would be identical to the number of electrons. In other words, the electron passes through a medium that includes the electrons of all the elements without considering their weight percentages. By increasing the kinetic energy, the electron's movement through the medium is also enhanced; Thus, less Coulomb forces affect the electron, and as a consequence, the effective atomic number decreases.

It can be observed that Z eff for some compounds like beryllium Oxide and lithium fluoride, which are known as tissue equivalent dosimeters, are close in value. Also, the relative difference between effective atomic number of the alanine and polystyrene, known as a blood equivalent tissues, is 14%. Teflon, Perspex, Nylon, and even Polycarbonate, widely used as bone, tissue, and brain equivalent material, have slightly different atomic numbers compared with bone, tissue, and brain. Nevertheless, studies on some widely known detector materials, namely, Cadmium telluride, Cadmium tungstate, and Bismuth germanium oxide, resulted from high effective atomic numbers, which make them suitable to be utilized as detectors.

According to Table 3 data, it can be obtained that the effective atomic number values decrease by increasing the kinetic energy of the electron particles. The variations in effective atomic number by increasing kinetic energy of the electron for water, lithium fluoride, aluminum oxide, magnesium oxide, and cadmium telluride are depicted in Fig. 1.

Zeff of the proton, alpha, and carbon particles

The experimental data from SRIM software, ASTAR, and PSTAR database and theoretical data of collisional the stopping power of electron have been determined and compared with each other. The kinetic energy ranges where the relative difference percentages of the results are less than 20% are identified as valid kinetic energy ranges (Table 4).

In therapeutic processes, 60 MeV up to 250 MeV proton, 5 MeV up to 9 MeV alpha, and 1200 MeV up to 2400 MeV carbon are usually used. Therefore, determining Z eff in the mentioned energies is more critical.

The results of calculating the effective atomic number for all the compounds in the energies mentioned above ranges of the proton, alpha, and carbon particles are shown in Table 5. Since Eq. ( 2) is most important in high kinetic energy ranges, this area's data is selected and studied. As can be seen, for the proton and heavy charged particles interactions, the Z eff value, is nearly equal to the total number of electrons of the compound. The results can be explained as the determinations are based on collisional stopping power. Variations of Z eff with the kinetic energy of alpha, proton and, carbon for water, lithium fluoride, aluminum oxide, magnesium oxide and, cadmium telluride are shown in Figs. 2, 3, 4.

When a charged particle passes an absorber, it loses kinetic energy through several events. The particle interacts with many electrons; moreover, in low energies, a positively charged particle intends to gather the electrons of the absorber. This process causes a decrease in the particle charge and lowers the loss of linear kinetic energy. At the end of the path, the particle absorbs Z electrons and turns into a neutral atom.

Results showed that in low energies of the electron, the effective atomic number is close to the number of electrons in each compound molecule. As the results are obtained using collision-stopping power, it can be concluded that the electron has had Coulomb interaction with all the electrons while passing the medium. So, the value of Z eff would be equal to the total number of electrons. In other words, the electron has entered a medium containing all elements' electrons regardless of their weight percentage. The effective atomic number will decrease by increasing kinetic energy since the electron will move faster in the medium and affect less Coulomb forces.

Accordingly, Z eff does not have a unique value to be used in the entire kinetic energy region of certain ionizing radiation due to the fact that multi-element materials have many constituents with different atomic numbers, which results in different radiation interaction probabilities in different kinetic energy regions. Therefore, Z eff is considered as a kinetic energy-dependent parameter that depends on the chemical composition of the corresponding material. In these circumstances, some materials that are equivalent in the presence of photons might not be equivalent in the presence of electrons, protons, alpha, and carbon. As in some previous studies, the kinetic energy of photons has been indicated as an effective parameter assessment of two equivalent materials.

In the present work, the collision-stopping power method is used to calculate the effective atomic number in different energies. Studies showed that an effective atomic number depends on the particle's kinetic energy, in which for charged particles, the interpolation of collision-stopping power values based on the element's atomic number is considered. Although the basis of final results in ESTAR, PSTAR, ASTAR, and SRIM is, in fact, Bethe's formula. But it should be considered that in the calculations of library data, ionization and excitation mean kinetic energy parameters, layers correction, and density effect correction also have been applied. Regarding the process of transferring the kinetic energy of charged particles to the medium, the calculated effective atomic number is equal to the total electrons of each compound, and its value will decrease by increasing kinetic energy.

Conclusion

In this paper, an effort has been paid to calculate the effective atomic number for some of the charged particles using a simple direct method. The effective atomic number of some materials used in dosimetry and some tissue equivalent for electron, proton, alpha, and carbon interactions were calculated. The results of these calculations are equal to the total electrons in each molecule of the compounds, which is justifiable by Bethe's formula physics. Consequently, some materials considered to be equivalent were proved not to be quite equivalent. These incompatibilities cannot reject or approve the commonly used methods for determining the Z eff, but in fact, they can result in a discussion on valid kinetic energy ranges for each method. In other words, regarding the particles' type, incident kinetic energy, and different kinetic energy ranges, one of the mentioned methods would be valid for determining the effective atomic number.

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Authors and Affiliations

1. Radiation Application Research School, Nuclear Science and Technology Research Institute (NSTRI), Tehran, Iran

Peiman Rezaeian & Sedigheh Kashian

2. Physics Department, K. N. Toosi University of Technology, Tehran, Iran

Rojin Mehrara

Contributions

P.R. wrote the manuscript text, prepared figures and tables and reviewed the manuscripts. R.M. wrote the manuscript text. Also, S.K. prepared the figures and reviewed the manuscript.

Corresponding author

Correspondence to Peiman Rezaeian.

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Rezaeian, P., Kashian, S. & Mehrara, R. Investigation of the effective atomic number dependency on kinetic energy using collision stopping powers for electrons, protons, alpha, and carbon particles. Sci Rep 13, 3573 (2023). https://doi.org/10.1038/s41598-023-30491-5
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DOI: https://doi.org/10.1038/s41598-023-30491-5

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Investigation of the effective atomic number dependency on kinetic energy using collision stopping powers for electrons, protons, alpha, and carbon particles - Scientific Reports

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As an important component in medical applications, dosimetry, and radiotherapy studies, the effective atomic number of body tissue, tissue equivalent substances, and dosimetry compounds are investigated. In this research, considering the Coulomb interaction of charged particles, using the collision stopping power and the NIST library data, the effective atomic number of various materials at different energies is calculated for common radiotherapy particles such as electron, proton, alpha, and carbon ions.

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The  simple future tense is used to describe activities in the future. The structure of the simple future tense is "will + verb", also for predictions or warnings of activities in the future the structure is "am/ is/ are + going to+ verb"

Examples: "I´m so hungry. I´ll make dinner." / "I think I´m going to stay in Austin for one more year."

Example 1 found in authentic material: “The National Transportation Safety Board said Tuesday it will investigate a December flight in which a United Airlines plane descended to within less than 800 feet (250 meters) of the ocean surface after taking off from Hawaii..” Newspaper article: https://www.cbsnews.com/sanfrancisco/news/plane-steep-dive-maui-hawaii-sfo-ntsb-to-investigate/

Example 2 found in authentic material:“I do think clerical white-collar work is going to be able to be replaced by this,” Arvind Krishna, chairman and CEO of IBM, told the Financial Times in an interview published Thursday" Newspaper article: https://fortune.com/2023/02/16/ibm-ceo-ai-will-replace-clerical-work-and-avert-labor-crisis-population-crisis/

Reflection: The clue is to identify the intention in the activity: quick decisiones and de use of adverbs such as "maybe, perhaps, possibly, probably, and definitely"; if the acction is a planned future activity, typically, "be going" is used for plans in the future.

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The past perfect continues tense is used to describe earlier activities between two past situations. The structure of the past perfect continuous tense is "had been + verb + ing"

Example: "I had been working on my online homework since Monday when the light went out."

Example found in authentic material: “That has intensified in recent weeks, as Mr. Smith’s staff — led by Thomas Windom, a veteran prosecutor who had been working out of the office of the U.S. attorney in Washington — has pored through hundreds of witness transcripts turned over by the House committee that investigated the Jan. 6 attack.” Newspaper article: https://www.nytimes.com/2023/02/09/us/politics/pence-subpoena-trump.html

Reflection: The clue is to identify the first activity when there is a relation in a sentence of two past activities, which the first one must be in the past perfect continuous tense.

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Pence Gets Subpoena From Special Counsel in Jan. 6 Investigation

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The move by Jack Smith, the special counsel, is one of the most aggressive in his investigation of Donald Trump’s efforts to stay in power and is likely to lead to a battle over executive privilege.

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The present perfect tense is used to describe activities and states completed recently or at an indefinite time in the past, or beginning in the past and continuing in the present. The structure of the present perfect tense is "have/ has + past participle."

Example: "I have worked on this dissertation for two years."

Example found in authentic material: “There have been many untimely, unexpected funerals in this northern Donbas town in recent months.” Newspaper article: https://www.bbc.com/news/world-europe-64446436

Reflection: It is difficult to understand the difference between present perfect and present perfect continues. If the sentence is already written is easy to recognize the different structures: in the case of the present perfect the verb tens is in past participle and in the present perfect continues case the structure of the verb has an “ing” at the end. But when you are thinking to express some idea or fill in the blanks, they are very similar, as they are states or activities beginning in the past and sometimes ongoing in the present.

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Against a backdrop of muffled booms from the frontlines to the south and east, people sank to their knees and threw roses in front of the van as it inched past them.

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"Denys - there are many angels on your shoulders today - the angels of those you brought back home," said Alexey Yukov, the local head of Black Tulip, addressing the crowd. "Because of your work so many soldiers, who died in places no one would ever have looked, have been reunited with their families."

Sosnenko died last week when the van he was driving - a van very much like the one that carried his body into the town square - hit an anti-tank mine close to the frontlines.

"He always said 'this is my mission - I have to do this'. It was dangerous work, but he would reassure us, saying 'don't worry, we are protecting the souls of the dead,'" his mother Ludmilla said. "He was always cheerful and had big plans for life after the war."

Last year, the BBC filmed Sosnenko and his team at work more than once.

He spoke of the horrors of the job, picking bodies up, piece by piece, and of the constant dangers - not just from the war raging around them, but from boobytraps often hidden beneath corpses, allegedly by retreating Russian troops. The team often use drones and other equipment to search for explosive devices.

But Sosnenko and his colleagues also talked passionately about the importance of their work.

Many of the bodies they've collected over the past 11 months have been those of Russian soldiers which have then been exchanged, across the frontlines, for the bodies of missing Ukrainian servicemen.

"We feel a sense of grace in doing this, in bringing people home to their families," Artur Semeyko - who worked alongside Sosnenko - said, recalling the peace they had brought to people who had previously been unable to arrange a proper funeral for their missing relatives.

Speaking after Sosnenko's funeral, in a snow-bound cemetery on the edge of Slovyansk, Mr Semeyko insisted that nothing had changed.

"We are glad we were able to bury him with honour," said Mr Semeyko. "He accomplished so much in such a short life, but now we must continue our work to bring more people home."

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Ukraine war: Funeral held for battleground body collector

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Against a backdrop of muffled booms from the frontlines to the south and east, people sank to their knees and threw roses in front of the van as it inched past them. Then, as the back door opened and a wooden coffin was pulled out, the sobbing began. "My son!

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The present continues is used: to talk about what is happening at the exact moment of speaking or over an extended period.

Example: I am developing a method to study and work these days.

Example found in authentic material: "Poker Face," from "Knives Out" director Rian Johnson, arrives on Peacock Thursday. Natasha Lyonne produces and stars in this 10-part mystery series about a woman who can tell when people are lying. Newspaper article:  published by CNN, January 22, 2023.

Reflection: Is easy to find the present continuous tense by recognizing the formula (am/is/are)+ verb+ ing. The difficulty is to identify the stative verbs which are not used in this tense.

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Welcome to the Year of the Rabbit! Today is Lunar New Year, but celebrations in many parts of the world will occur over several days -- collectively referred to as the Spring Festival. One Lunar New Year tradition involves eating what are known as longevity noodles , a ritual that can be traced back more than 2,000 years.