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Children treated for cancer with approaches such as chemotherapy can develop therapy-related myeloid neoplasms (a second type of cancer) with a dismal prognosis. Scientists at St. Jude Children's Research Hospital have characterized the genomic abnormalities of 84 such myeloid neoplasms, with potential implications for early interventions to stop the disease. A paper detailing the work was published today in Nature Communications.

The somatic (cancer) and germline (inherited) genomic alterations that drive therapy-related myeloid neoplasms in children have not been comprehensively described, until now. The researchers used a variety of sequencing techniques (whole exome, whole genome and RNA) to characterize the genomic profile of 84 pediatric therapy-related myeloid neoplasms. The data came from patients with leukemia, solid tumors or brain tumors who were treated with different types of chemotherapy and who all later developed myeloid neoplasms.

"One thing that we've known for a long time is once kids develop this secondary tumor, the outcome is really poor," said co-corresponding author Jeffery Klco, M.D., Ph.D., St. Jude Pathology. "The alterations that drive these tumors are different in children than they are in adults, underscoring the need to study these tumors specifically in pediatrics."

Collaboration yields new understanding

Results of the study revealed several notable mutations in the somatic setting, including changes in the Ras/MAPK pathway, alterations in RUNX1 or TP53, and rearrangements of KMT2A. Additionally, the results showed increased expression of a transcription factor called MECOM, which was associated with MECOM's abnormal proximity to an enhancer as a result of genetic rearrangements.

The research benefited from computational tools developed at St. Jude that are aimed at reducing error rates, including CleanDeepSeq and SequencErr. These approaches help to discriminate between true mutations and sequencing errors.

With these tools, the researchers could trace the mutations back as far as two years before a therapy-related myeloid neoplasm developed, when early interventions could potentially benefit patients.

"This work indicates that we can detect this type of malignancy early, to study if preventative therapies could benefit patients," said co-senior author Xiaotu Ma, Ph.D., St. Jude Computational Biology.

An international research team led by Professor Kari Rissanen of the University of Jyvaskyla (Finland) and Professor Antonio Frontera of the University of Balearic Islands (Spain) has demonstrated that positively charged iodine (termed iodonium) is able to favorably interact with a silver cation (Ag+), overcoming the strong electrostatic repulsion. The research was published online in Chem -journal 8th of February 2021.

It is well known and intuitive that iodide (I-) has a strong affinity for Ag+. For instance, AgI is one of the most insoluble inorganic salts due to the strength of their attractive electrostatic force. In fact, it is used to generate artificial rain (cloud seeding) because the crystalline structure of AgI is similar to that of ice (ideal nucleation agent).

However, the strong and counter-intuitive affinity of iodonium (I+) for Ag+ was not known until now. An international research group have succeeded in preparing and characterising a supramolecular complex where I+ and Ag+ are in close contact, thus overcoming the intrinsic electrostatic repulsion of their positive charges. Remarkably, the I+···Ag+ interaction was demonstrated both in the solid state and in solution.

"The explanation provided is that the iodine atom, even as a positively charged cation, is able to generously donate electrons from its free electron lone pairs to the Ag+. Therefore, no matter the electronic nature of iodine, rich or poor, it seems its generosity toward the Ag+ is boundless", says Professor Kari Rissanen from University of Jyvaskyla.

In a courtesy call to HE the President of Malta at San Anton Palace on Thursday, February 11, 2021, Dr Noel Aquilina from the Department of Chemistry, accompanied by Professor Emmanuel Sinagra, Head of the Department of Chemistry and Dean of the Faculty of Science at the University of Malta, presented the findings of a landmark study. This study shows and confirms that airborne particulate matter (PM), apart from several toxic components, is also contaminated with tobacco smoke-driven particulates.

After 30 years, Dr Noel Aquilina, alongside world renowned tobacco smoke-related researchers, Emeritus Professor Neal L. Benowitz and Dr Peyton Jacob III from the University of California San Francisco (UCSF), USA and atmospheric chemist and Fellow of the Royal Society, Professor Roy M. Harrison, from the University of Birmingham, UK, ended the wait for the elusive marker!

This remarkable study was published in one of the most prestigious journals of air quality, Environment International and was supported by the California Tobacco-Related Disease Research Program, the National Institute on Drug Abuse, the National Center for Research Resources and the UCSF Bland Lane Center of Excellence on Secondhand Smoke.

About 6 trillion cigarettes were smoked worldwide in 2016. Considering a conservative value, worldwide, Secondhand Smoke (SHS) (from cigarette smoking alone), releases about 22 million kilograms of nicotine and about 135 million kilograms of PM into the atmosphere each year. What is the fate of those particles?

The criteria for an ideal marker are that this is expected to behave similarly to the material for which it is a marker (in this case, cigarette SHS PM) under a range of environmental conditions and can be detected at low concentrations. For this purpose, historically, several studies tried to find a marker to show exposure to ambient SHS. Since 1991, the main marker of choice was Nicotine. Later studies have verified that nicotine is found almost exclusively in the gas-phase and would underestimate the exposure to the particle-phase of SHS; ages differently from other substances thus explaining the poor correlation with other SHS components; it has high adsorption rate to surfaces and easily desorbs from surfaces in the absence of active smoking. This meant that Nicotine was neither adequate nor suitable as a marker to SHS in PM. Over the last 3 decades, 16 different markers were tried and tested but all failed in one way or another to satisfy the necessary marker characteristics.

nicotelle

In 2013, at the Division of Cardiology, Clinical Pharmacology Program, Department of Medicine, UCSF, Nicotelline, a tripyridine alkaloid found in tobacco leaves and tobacco smoke, having a low volatility, led to hypothesize that it would be found mainly in the PM of SHS and should therefore be a useful tracer for tobacco smoke PM. It was thought that Nicotelline would be expected to be more stable in the environment than previously tested tracers for SHS. The 2013 study led by Dr Jacob III, was limited to a chamber, highly controlled environment, dealing with very few short-time airborne samples and deposited dust samples. Those findings were not sufficient to verify the requested marker characteristics.

In 2016, Dr Aquilina, one of the few European Affiliate Researchers of the Thirdhand Smoke (THS) Research Consortium, was invited by UCSF to:

Coordinate a comprehensive air sampling campaign in several countries with different climates, to show the ubiquitous presence of Nicotelline in airborne samples. Samples were collected in six cities in California including San Francisco; USA, Birmingham; UK, three sites in Hong Kong; PR China and Msida; Malta;

Develop an analytical method to extract Nicotine, Nicotelline and other tobacco-related compounds from airborne sample;

Validate the extraction method against a standard reference material and show that Nicotelline can be detected reliably at very low concentrations;

Carry out tests to verify the atmospheric stability of Nicotelline in relation to Nicotine in PM.

The samples for the test to show the most important and necessary property for a marker, atmospheric stability, and hence confirm its suitability as a marker, have been collected on the University of Malta, Msida campus in 2018 using the Mobile Air Quality Laboratory equipment operated by the Faculty of Science. A suite of real-time monitors were used in conjunction with localised meteorological data to verify the atmospheric conditions which could influence the stability of Nicotelline on filters during sampling.

The study has shown that:

Nicotelline can be considered as a suitable marker for tobacco-smoke driven particulate matter in SHS;

The marker shows a ubiquitous presence even at low concentrations and geographical variability linked to population density and tobacco use prevalence;

The mean load of tobacco smoke particulate in airborne particulate matter is 0.06 %.

In 2010, about 1 % of the global mortality was attributed to SHS exposure. Lower respiratory infections in children younger than 5 years, ischaemic heart disease in adults, and asthma in adults and children indicate there is no risk-free level of exposure to SHS.

Given the abovementioned health implications, what does this study add to the scientific community?

Although airborne PM is generally loaded with several pollutants that can be mutagenic, genotoxic and carcinogenic due to different sources, now it is confirmed that a small load of PM comes exclusively from tobacco smoke, hence air is also contaminated with tobacco smoke.

Although the load appears to be too low to be of an immediate hazard, this marker has set a new standard on the possible chronic exposure to SHS/THS through inhalation of PM even in non-smoking environments.

The importance and significance of this study is that it has opened a gateway to research the potent tobacco-specific carcinogens present in PM, and their health implications in inducing lung cancer, but not only, associated with a continuous exposure. These are THS components which are the frontier of science associated with tobacco smoke and its health effects. There is the need to look into additional exposure pathways, including dermal uptake, hand-to-mouth transfer and by inhalation of secondary particles that form after re-emission from surfaces. This is where a suitable particle-phase marker will be used, to distinguish the contribution of past indoor smoking from what is an unavoidable contamination originating outdoors.

"We are surrounded by a huge number of systems - biological, technical, economic, which we can influence, which we can control. The task is to do it optimally, for example, reaching the desired point with a minimum of effort, resources, and time, - explains Prof. Yurii Averboukh. - From a mathematical point of view, the task is narrowed down to the theory of optimal control. A classic example of this theory is moon landing: fuel consumption optimization enables to increase cargo volumes transported to the moon".

A special section of optimal control theory is the theory of differential games. It studies the control of one, several, or many objects in a conflict situation and based on current information about the behavior of the players - both leading (fleeing) and followers (catching up). Like the whole theory of optimal control, the theory of differential games is closely related to the theory of differential equations in partial derivative.

A strong connection between the theory of partial differential equations and differential games was established in the 1970s-1980s by the most prominent representatives of the Ural mathematical school, academicians Nikolai Krasovski, who developed the concept of stability, and Andrei Subbotin, who expressed the stability condition in the form of partial differential equations.

"The stability function is a function of the minimum guaranteed result of the &laquocontrolling» player. According to the Krasovski's theory, we "force" our "fleeing" opponent, be it a person, a technical device, or forces of nature, to "tell" us about their managerial intentions. Based on this data and calculating the number of this player's gains as a result of the game, you can estimate your own final gains. The situation when at the end of the game we do not make our results worse, corresponds to the stability condition - says Yurii Averboukh. - Since we understand what we will get in the end, the situation gets completely predictable. That is, the calculation of the stability function allows you to foresee and predict the result of the development of the situation and, consequently, to build a strategy for managing it."

"The genius of the approach of Academicians Krasovski and Subbotin is that having developed the so-called strategy of extreme shift, they showed how, knowing the" intentions "of the opposing player, in this case, the wind, who is ready to" tell "about his plans to control the plane (let's call such a player "Stupid", "dummy"), play against the "smart", "malicious", that is, the real wind. Thus, to fulfill the stability condition, it is enough to play against the "dummy" wind, and to play against the "smart" player, the real wind, you need to calculate the stability function by solving the partial differential equations," continues Prof. Yurii Averboukh.

The scientist, in turn, wondered: is the Krasovski-Subbotin's concept of stability applicable to the situation of managing a large number of similar objects. In his article published in the Journal of Mathematical Analysis and Applications, Prof. Averboukh substantiated a positive answer to this question. He showed how the solution looks in the form of partial differential equations.

"The matter turned out to be not easy: after all, we are dealing with many agents, assuming that their number is infinite, like the number of molecules in the air. To ensure that all the objects act in a consistent manner, each of them needs to be shown how to manage it. At the same time, we assume that a separate object acts without "recognizing" the others separately, but perceiving them as an "impersonal" mass, that is, in the so-called "middle field," says Yurii Averboukh. "The use of the description language of measures (shares) that gives an idea of the density of objects within the boundaries of a certain area, allowed us to cope with this problem".

The most obvious practical application of the research results of Yurii Averboukh today is the control of squadrons of unmanned aerial vehicles.

"Let's imagine that the drones are tasked to divide themselves across the field at a given time and treating it from pests. In this case, the wind affects the drones. Having determined their density in a particular zone at the start from the ground (for example, it turns out that 20% of drones are concentrated in one area, and 80% in another) and calculating the stability function, we can, firstly, give the drones a command to distribute more uniformly, and, secondly, confidently predict that at a certain moment the error in their uniform distribution will be, say, 10%, after some time - 9%, and so on, and at the end - 5%, which will be an acceptable minimum value. That is, the solution to the stability function will show how to move the drones to take the optimal position over the field at the right time, "explains Yurii Averboukh.

In this case, the "dummy" we are playing against in PDEs is the "dumb" wind that "tells" how it will affect the drones. Knowing this and according to the Krasovsky-Subbotin extreme shift strategy, one can calculate how the "smart and evil" wind will act, that is, what effect it will have on drones in reality and, therefore, how they need to move in order not to worsen the result, but if possible improve it.

In the future, according to Yurii Averboukh, the same principles can be applied in the management of nanoparticles, for example, to transport drugs to a certain part of the body.

Novel genetic associations could pave the way for early interventions and personalized treatment of an incurable condition.

Scientists from the University of Bergen (Norway) and Karolinska Institutet (Sweden) have discovered the genes involved in autoimmune Addison's disease, a condition where the body's immune systems destroys the adrenal cortex leading to a life-threatening hormonal deficiency of cortisol and aldosterone.

Groundbreaking study

The rarity of Addison's disease has until now made scanning of the whole genome for clues to the disease's genetic origins difficult, as this method normally requires many thousands of study participants. However, by combining the world's two largest Addison's disease registries, Prof. Eystein Husebye and his team at the University of Bergen and collaborators at Karolinska Institutet in Sweden (prof. Kämpe) were able to identify strong genetic signals associated with the disease. Most of them are directly involved in the development and functioning of the human immune system including specific molecular types in the so-called HLA-region (this is what makes matching donors and recipients in organ transplants necessary) and two different types of a gene called AIRE (which stands for AutoImmune REgulator).

AIRE is a key factor in shaping the immune system by removing self-reacting immune cells. Variants of AIRE, such as the ones identified in this study, could compromise this elimination of self-reacting cells, which could lead to an autoimmune attack later in life.

Knowing what predisposes people to develop Addison's disease opens up the possibilities of determining the molecular repercussions of the predisposing genetic variation (currently ongoing in Prof. Husebye's lab). The fact that it is now feasible to map the genetic risk profile of an individual also means that personalised treatment aimed at stopping and even reversing the autoimmune adrenal destruction can become a feasible option in the future.

Tumor cells are able to avoid the attack of the immune system through several mechanisms. For instance, these can secrete factors that turn macrophages -cells in the immune system- into dual action agents that contribute to the tumor progress and will protect it from immune body defences: these become, thus, the tumor-associated macrophages (TAMs).

An article published in the journal Cancer Research describes a new molecular mechanism that counteracts the immunosupressive action of these macrophaes to boost tumor growth, and brings knowledge of potential interest for the design of future therapeutical options against cancer. The preclinical study is led by the tenure-track 2 lecturer Annabel Valledor, from the Faculty of Biology and the Institute of Biomedicine of the University of Barcelona (IBUB).

Among the participants are also the researchers of the Faculty of Pharmacy and Food Sciences of the UB, the Josep Carreras Leukaemia Research Institute, the Sant Pau Institute of Biomedical Research, the University of Las Palmas de Gran Canaria, University College London, and the Free University of Brussels, among others.

Macrophages that boost tumor growth

Macrophages are cells in the immune system that unfold several functions (they kill invasive pathogens, remove cells or damaged tissue, etc.). However, in the tumoral microenvironment, tumor-associated macrophages can become an enemy to patients with cancer. Therefore, a field of study of great outreach in biomedicine is the one finding strategies to activate TAMs and help the immune system fight tumors, as well as improve the effects of anticancer therapies.

The article published in Cancer Research describes how the action of a compound known as TO901317 limits the ability of TAMs to protect the tumor in laboratory animals. According to the results, the TO901317 compound can inhibit the synthesis of molecules that serve to attract regulatory T lymphocytes (Treg) to the tumor.

"In a healthy person, the most important function of Treg is to maintain the balance of the immune system and avoid unwanted responses towards the own body. However, in a tumor, Treg stop the antitumoral activity of other types of lymphocytes. Actually, several studies show that a high number of Treg in the tumoral microenvironment suggests a worse prognosis", notes lecturer Annabel Valledor, from the Department of Cell Biology, Physiology and Immunology and IBUB.

Antitumoral effects of LXR activation

In particular, the TO901317 compound acts on the liver X receptor (LXR), a transcription factor of the family of nuclear receptors that regulates the gene expression with a key role in the activity of macrophages and the metabolism.

As stated in the article, the activation of LXR by the antagonist TO901317 inhibits the expression of the transcription factor IRF4 in macrophages. Specifically, the IRF4 factor is necessary so that chemokines Ccl17 and Ccl22 are expressed as a response to signals such as interleukin IL-4 or the GM-CSF factor. As a result, the action of the TO901317 compound inhibits the production of chemokines Ccl17 and Ccl22, which are important for the recruitment of regulatory T lymphocytes to the tumoral microenvironment.

"Once the LXR is activated, tumor-associated macrophages undergo important changes in their gene expression profile, and as a result, their ability to produce molecules with an immunopressive function in the tumoral microenvironment decreases", notes researcher Joan Font Díaz, from the Faculty of Biology and IBUB.

This action is correlated to a decrease in the number of Treg in the tumor and a slower tumor growth, as stated by the authors of the study.

New research shows that hurricane maximum wind speeds in the subtropical Atlantic around Bermuda have more than doubled on average over the last 60 years due to rising ocean temperatures in the region.

Hurricanes intensify by extracting energy from the warm ocean surface via air-sea heat fluxes, so a warmer ocean can lead to more intense hurricanes.

Improving predictions of wind speeds from hurricanes will help determine the right level of response in advance of the storm and potentially limit the resulting damage in Bermuda.

Between 1955 and 2019 mean hurricane intensity near Bermuda, measured by the maximum wind speed, increased from 35 to 73mph - equivalent to over 6mph per decade. At the same time sea surface and sub surface temperatures in the region increase by upto 1.1°C, providing the additional energy for hurricanes to intensify.

The study, published in Environmental Research Letters, also develops a predictor for the intensity of hurricanes moving through the Bermuda area using the average upper ocean temperature in the top 50m layer.

Samantha Hallam, the lead author of this paper from the University of Southampton and the National Oceanography Centre (NOC), said , "The approach we used could provide a better way to predict Bermuda storm intensity than current theory or operational methods alone. It could also be use elsewhere in the subtropical Atlantic where there is a shallow mixed layer depth, typically north of twenty five degrees north.

"We used hurricane potential intensity theory, locally-based weather balloon soundings, surface and upper ocean observations of conditions in and around hurricanes passing within 100km of Bermuda over the last 65 years (including direct hits and 'near-miss' storms)."

Mark Guishard, co-author and Director of the Bermuda Weather Service said "the research demonstrates the greater relevance of upper ocean heat versus sea surface temperatures alone in the prediction of hurricane intensity. Preliminary testing with the recent passage of Hurricane Paulette shows promising results that this technique could be further developed into an additional operational tool for forecasters locally."

These findings are the result of a statistical analysis on hurricane paths within 100km of Bermuda, between 1955 and 2019. The research used surface and subsurface ocean temperature observations from the Bermuda Atlantic Times Series (BATS) Hydrostation S programme, managed by the Bermuda Institute of Ocean Sciences.

In Huntington's disease, a faulty protein aggregates in brain cells and eventually kills them. Such protein aggregates could, in principle, be prevented with a heat shock protein. However, it is not well known how these proteins interact with the Huntington's disease protein. New research by Patrick van der Wel (University of Groningen, the Netherlands) and colleagues at the University of Texas has partially resolved the structure of heat shock proteins that bind to such aggregating proteins, helping us to understand how they work. The results were published on 11 February in the journal Nature Communications.

Heat shock proteins (Hsp) are produced by cells that are exposed to stressful conditions. The Hsp family is diverse, and quite a few of the proteins function as chaperone. This means that they help other proteins to fold (or re-fold after being damaged) in the correct way. "These proteins can assist in folding thousands of different proteins. To this end, they use co-chaperones with specific binding abilities," explains Patrick van der Wel, Associate Professor of Solid-State NMR Spectroscopy at the University of Groningen.

Ordered

One class of heat shock proteins, Hsp40, helps to suppress protein aggregates like those that appear in Huntington's disease. These Hsp40 proteins come in different kinds, and some of them will bind specifically to aggregating proteins with a lot of repeated glutamine amino acids, like the faulty protein found in Huntington's disease. One of these Hsp40 proteins is called DnaJB8, and this was the protein studied by Van der Wel and his colleagues.

"In order to understand the action of DnaJB8, we need to know what it looks like," says Van der Wel. However, it is difficult to resolve the structure of this type of protein. "It appears as a dimer or an oligomer, so a number of these protein units work together, but their structure is not really ordered," he continues. This makes it impossible to use standard techniques, which all require ordered structures.

Carbon atoms

Van der Wel was asked by colleagues at the University of Texas to help tackle this problem. Van der Wel is specialized in solid-state NMR spectroscopy, a technology that can measure how atoms are connected to each other. In simple terms, the NMR signals of two connected carbon atoms in DnaJB8 depend on how they interact with other atoms in the molecule. Therefore, the measured spectrum of the carbon atoms can show in which amino acid they are located. Such information can be used to get an idea of the protein's structure, even if it is not well ordered.

The DnaJB8 protein is made up of different domains, with different functions. Through a series of experiments, Van der Wel was able to determine which domains are stuck inside the DnaJB8 protein, and which are available on the outside. The experiments suggested that the so-called 'J domain' of DnaJB8 was able to switch between being stuck and being accessible. This is important because this part of the DnaJB8 protein is responsible for turning on the Hsp70 protein, which can prevent the protein aggregates from forming. In other words, there seems to be a 'switch' in DnaJB8 that controls this interaction with Hsp70. Interestingly, this switch was found to be located in a domain of DnaJB8 whose exact role was previously unclear.

Hypothesis

"Thus, our hypothesis based on the structure was that the DnaJB8 is inactive until it binds to the faulty proteins and that it then attracts Hsp70," says Van der Wel. A series of simulations and experiments at the University of Texas confirmed this idea and yielded a detailed model of how these proteins work together.

DnaJB8 is a protein that is mainly found in the testes. However, a very similar protein called DnaJB6 is present in the brain, where Huntington's disease strikes. It seems more than likely that this protein acts similarly, when it protects against glutamine-rich proteins that aggregate in the brain cells of patients. "It may take many more years, but now that we understand how this process works, it could help us to find a way to enhance the activity of DnaJB6, which could reduce the protein aggregates that cause the disease," concludes Van der Wel.

Scientists have accepted natural selection as a driver of evolution for more than 160 years, thanks to Charles Darwin.

But University of Cincinnati biologist Michal Polak says Darwin's book "The Descent of Man" only tells part of the story. Sometimes when the victor vanquishes his sexual rival, the quest to pass genes to the next generation is just beginning.

According to a new UC study published in the journal Current Biology, male fruit flies with the most impressive sexual ornamentation also have super sperm that can outcompete that of rivals in the post-mating fertilization game.

UC studied Drosophila bipectinata, a tiny red-eyed fruit fly from the South Pacific. The male's forelegs have a distinctive "sex comb," dark bristles that female fruit flies find appealing -- like the colorful train of a male peacock. Scientists previously found that female flies prefer males with more robust sex combs, which the males use to grasp the female's abdomen before mating.

UC researchers found a strong link between the most impressive sex combs and that male's competitive success at passing on his genes even after a female fly has mated with other flies. And this competitive edge persisted even after the male's sex comb was surgically removed with a high-precision laser in UC experiments.

"This is the first robust demonstration of a genetic link between a traditionally Darwinian trait and success in postcopulatory sexual competition," Polak said. "That's the surprising link: precopulatory and postcopulatory fitness."

In his groundbreaking 1859 book "On the Origin of Species," Darwin framed the idea of natural selection by describing how the "fittest" animals pass on their genes to the next generation. This fitness is manifested in having the largest antlers, the most vibrant colors or the vigor to defend a territory.

But Darwin's theory was incomplete, Polak said, because it failed to recognize that sexual selection continues during and after mating. Female fruit flies are promiscuous, often choosing multiple mates. Fruit flies are hardly alone in that regard, Polak said.

"Promiscuity is much more common across animal species than once was thought," Polak said. 

Scientists living in prim and proper Victorian England did not give enough consideration to the microscopic race to fertilize that begins after mating among multiple successful suitors.

"You have to consider the social context in which Darwin was living," Polak said. 

What females gain from mating with multiple suitors is not always clear, Polak said. But when they do, postcopulatory sexual selection provides a competitive edge.

"It's evident even in primates. Female chimpanzees and bonobos are promiscuous, so the males have large testes that produce big volumes of sperm," Polak said.

"And you have species like gorillas where females are not promiscuous. Silverback males enforce monogamy. And lo and be hold, their testes are much smaller relative to body size compared to chimps."

And if you're wondering, the relative size of human testes falls somewhere between gorillas and chimps, Polak said.

Polak, a professor of biology in UC's College of Arts and Sciences, decided to study this species of fruit fly after encountering it while conducting fieldwork in Queensland, Australia.

"I was watching these flies mate on a fruit and looked under the microscope and saw these beautiful sex combs. I thought it would make a good model system to study," Polak said.

"Sexual selection picks up on these traits and they become really exaggerated," he said.

For their study, UC biologists artificially selected males with the largest and smallest sex combs in 11 successive generations of fruit flies to create high and low genetic lines.

Kassie Hooker from 2012 to 2015 worked in Polak's lab as an undergraduate biology student, undertaking the arduous task of categorizing generations of male fruit flies based on the size of the sex combs on their legs. By counting the teeth in each comb, she separated the males with the largest and smallest sex combs to create distinct genetic lines.

To show that the male fruit fly's sex comb doesn't provide any reproductive benefit in mating, researchers used ultraprecise lasers to trim the sex comb in the high line males to mimic those found in the low line males. But these postsurgical males continued to fertilize more eggs even when females mated with lower-line males first.

The research was supported by the National Science Foundation.

UC assistant professor Joshua Benoit, a study co-author, analyzed the RNA of the flies and identified seminal fluid genes that may be responsible for giving high-line males a fertilization advantage.

"There aren't many studies more interesting than this one," Benoit said. "Sex, lasers, and male competition, which could describe most 1980s action movies."

Darwin proposed the theory of sexual selection to account for the evolution of male weaponry and extravagant ornamental displays, Polak said. But UC's study found a far more complex and interesting battle among the sexes.

"We established a link between Darwinian traits and the postcopulatory arena, which Darwin didn't recognize was important in evolution at all," Polak said.

Fast and energy-efficient future data processing technologies are on the horizon after an international team of scientists successfully manipulated magnets at the atomic level.

Physicist Dr Rostislav Mikhaylovskiy from Lancaster University said: "With stalling efficiency trends of current technology, new scientific approaches are especially valuable. Our discovery of the atomically-driven ultrafast control of magnetism opens broad avenues for fast and energy-efficient future data processing technologies essential to keep up with our data hunger."

Magnetic materials are heavily used in modern life with applications ranging from fridge magnets to Google and Amazon's data centers used to store digital information.

These materials host trillions of mutually aligned elementary magnetic moments or "spins", whose alignment is largely governed by the arrangement of the atoms in the crystal lattice.

The spin can be seen as an elementary "needle of a compass", typically depicted as an arrow showing the direction from North to South poles. In magnets all spins are aligned along the same direction by the force called exchange interaction. The exchange interaction is one of the strongest quantum effects which is responsible for the very existence of magnetic materials.

The ever-growing demand for efficient magnetic data processing calls for novel means to manipulate the magnetic state and manipulating the exchange interaction would be the most efficient and ultimately fastest way to control magnetism.

To achieve this result, the researchers used the fastest and the strongest stimulus available: ultrashort laser pulse excitation. They used light to optically stimulate specific atomic vibrations of the magnet's crystal lattice which extensively disturbed and distorted the structure of the material.

The results of this study are published in the prestigious journal Nature Materials by the international team from Lancaster, Delft, Nijmegen, Liege and Kiev.

PhD student Jorrit Hortensius from the Technical University of Delft said: "We optically shake the lattice of a magnet that is made up of alternating up and down small magnetic moments and therefore does not have a net magnetization, unlike the familiar fridge magnets."

After shaking the crystal for a very short period of time, the researchers measured how the magnetic properties evolve directly in time. Following the shaking, the magnetic system of the antiferromagnet changes, such that a net magnetization appears: for a fraction of time the material becomes similar to the everyday fridge magnets.

This all occurs within an unprecedentedly short time of less than a few picoseconds (millionth of a millionth of a second). This time is not only orders of magnitude shorter than the recording time in modern computer hard drives, but also exactly matches the fundamental limit for the magnetization switching.

Dr Rostislav Mikhaylovskiy from Lancaster University explains: "It has long been thought that the control of magnetism by atomic vibrations is restricted to acoustic excitations (sound waves) and cannot be faster than nanoseconds. We have reduced the magnetic switching time by 1000 times that is a major milestone in itself."

Dr Dmytro Afanasiev from the Technical University of Delft adds: "We believe that our findings will stimulate further research into exploring and understanding the exact mechanisms governing the ultrafast lattice control of the magnetic state."

WORCESTER, Mass. -- New research by Christopher A. Williams, an environmental scientist and professor in Clark University's Graduate School of Geography, reveals that deforestation in the U.S. does not always cause planetary warming, as is commonly assumed; instead, in some places, it actually cools the planet. A peer-reviewed study by Williams and his team, "Climate Impacts of U.S. Forest Loss Span Net Warming to Net Cooling," published today (Feb. 12) in Science Advances. The team's discovery has important implications for policy and management efforts that are turning to forests to mitigate climate change.

It is well established that forests soak up carbon dioxide from the air and store it in wood and soils, slowing the accumulation of greenhouse gases in the atmosphere; however, that is not their only effect on climate. Forests also tend to be darker than other surfaces, said Professor Williams, causing them to absorb more sunlight and retain heat, a process known as "the albedo effect."

"We found that in some parts of the country like the Intermountain West, more forest actually leads to a hotter planet when we consider the full climate impacts from both carbon and albedo effects," said Professor Williams. It is important to consider the albedo effect of forests alongside their well-known carbon storage when aiming to cool the planet, he adds.

The research was funded by two grants from NASA’s Carbon Monitoring System. Williams and his research team -- comprising data scientist Huan Gu, Ph.D. from The Climate Corporation and Tong Jiao, Ph.D. -- found that for approximately one quarter of the country, forest loss causes a persistent net cooling because the albedo effect outweighs the carbon effect. They also discovered that loss of forests east of the Mississippi River and in Pacific Coast states caused planetary warming, while forest loss in the Intermountain and Rocky Mountain West tended to lead to a net cooling.

According to Professor Williams, scientists have known for some time that expanding forest cover cannot be assumed to cool the planet or to mitigate global warming. However, this has not always been appreciated broadly.

"If we fail to consider both the carbon and the albedo effects, large-scale tree-planting initiatives, such as Canada's 2Billion Trees Initiative and The Nature Conservancy's Plant a Billion Trees campaign, could end up placing trees in locations that are counterproductive for cooling the climate system," said Professor Williams.

"It is all about putting the right trees in the right place," said Williams, "and studies like ours can help identify where the potential for cooling is greatest."

Every year, approximately one million acres of forest are being converted to non-forest areas across the lower 48 states of the U.S.; this is largely due to suburban and exurban expansion and development. Professor Williams' team found that the net climate impact of a full 15 years of forest losses amounts to about 17% of a single year of U.S. fossil fuel emissions.

Williams' research team used state-of-the-art satellite remote sensing to bring a detailed, observational perspective to examine this problem that had previously been assessed mostly with computer models. The three researchers pinpointed the locations of forest loss and identified what those sites became -- urban, agricultural, grassland, shrubland, pasture, or something else. They then quantified how much forest biomass carbon was released to the atmosphere, and how much additional sunlight was reflected out to space. By comparing these two effects they measured the net impact of deforestation on the climate system.

The new datasets and methods used in Professor Williams' study show that the tools are available to take the albedo effect into account. The Clark team hopes to generate actionable datasets to share with land managers and policymakers worldwide within the next one or two years, to help ensure that their tree-planting efforts focus on the right places and have the intended effects.

Researchers from University of Amsterdam and Stanford University published a new paper in the Journal of Marketing that examines explores how human-as-machine representations affect consumers--specifically their eating behavior and health.

The study, forthcoming in the Journal of Marketing, is titled "Portraying Humans as Machines to Promote Health: Unintended Risks, Mechanisms, and Solutions" and is authored by Andrea Weihrauch and Szu-Chi Huang.

To combat obesity, governments, marketers, and consumer welfare organizations often encourage consumers to make food choices more rationally. One strategy used is to leverage human-as-machine representations--portraying humans as machines. This approach tries to leverage people's existing associations about machines--that machines make decisions rationally--to help them approach food in a machine-like manner, with the goal of encouraging healthier choices.

For example, National Geographic's series "The Incredible Human Machine" describes unhealthy behaviors as (human) "errors" in the maintenance of our bodily machine; Centrum asks consumers to "power the human machine" with healthy food supplements; and the international event Men's Health Week compares the human body to a car and states that unhealthy food and beverage choices (i.e., alcohol) hurt your "engine." In addition, consumers experience human-as-machine representations in everyday life: virtual telepresence systems show people as human faces with mechanistic bodies, human enhancement technologies (e.g., augmented reality goggles) represent humans as more machine-like, and artificial intelligence (AI) software further blurs the line between humans and machines.

When consumers see humans portrayed as machines, they feel that they are expected to behave like machines and choose food like machines would--in a rational and calculating manner. This style of choice making is in line with the hopes of policy makers and can lead to desired effects (healthier choices) for some consumers. However, this expectation backfires for a very vulnerable segment of consumers--consumers who have low confidence in their ability to choose healthy food. For them, human-as-machine representations actually lead them to choose unhealthier options.

Why does this occur? Weihrauch explains that "For this consumer segment, the expectation that one should be rational and machine-like when it comes to food feels impossible. Instead of feeling motivated to be more rational, the feeling of not being able to perform like a machine triggers unhealthier choice making instead. Thus, a strategy used with good intentions to educate consumers and improve their health can have an unintended dark side that hurts the very segment that consumer welfare organizations want to help."

There is hope, though. Research provides a practical solution to help circumvent this backfire effect: accompany the human-as-machine visuals with a message to reassure consumers that making machine-like food choices is doable. By adding this message in a cafeteria, the study found that consumers' choice of healthy food increased by 22% for some.

These results ring a cautionary bell for nonprofit organizations, policy makers, educators, and for-profit health marketers: the use of human-as-machine imagery can be more complicated than intended because confronting consumers with expectations to be "machine-like" can be risky if not aligned with their abilities. Understanding the potential processes that cause indulgent food choices is also crucial for consumers, especially as human-as-machine stimuli become more prevalent in the lives of consumers around the world.

STEMOs (Stroke-Einsatz-Mobile) have been serving Berlin for ten years. The specialized stroke emergency response vehicles allow physicians to start treating stroke patients before they reach hospital. For the first time, a team of researchers from Charité - Universitätsmedizin Berlin has been able to show that the dispatch of mobile stroke units is linked to improved clinical outcomes. The researchers' findings, which show that patients for whom STEMOs were dispatched were more likely to survive without long-term disability, have been published in JAMA*.

The phrase 'time is brain' emphasizes a fundamental principle from emergency medicine, namely that after stroke, every minute counts. Without treatment, the brain will lose two million brain cells every minute. When dealing with stroke caused by an arterial blockage in the brain, prompt dissolution of the blood clot - known as thrombolysis - is essential.

Ten years ago, a team led by Prof. Dr. Heinrich Audebert (Center for Stroke Research Berlin (CSB) and Charité's Department of Neurology and Experimental Neurology) set itself the aim of further reducing time to treatment by bringing the necessary diagnostic and treatment procedures to the patient rather than the other way around. They did so with great success: Berlin's first purpose-built mobile stroke unit, developed in conjunction with the Berlin Fire Department and MEYTEC GmbH, was launched in February 2011. Following years of research, the team was able to confirm that STEMO-based stroke treatment is safe and, more importantly, reduces time to treatment. Today, the Berlin Fire Department operates three STEMO vehicles. As part of a collaboration between Charité, Vivantes - Netzwerk für Gesundheit GmbH and Unfallkrankenhaus Berlin, these vehicles cover most of the Berlin area. Data from the now-published B_PROUD study show that dispatch of STEMO mobile stroke units is associated with improved outcomes in patients with stroke.

"In our study, dispatch of a mobile stroke unit was linked to increased survival and reduced risk of disability," says Prof. Audebert. He adds: "The relative odds of these patients having significant disabilities three months after stroke was 29 percent lower than in patients cared for by the conventional emergency medical services. STEMO dispatch therefore results in significantly more stroke patients returning to an independent life after stroke." A selection of voices and opinions on the STEMO initiative - from Michael Müller (Governing Mayor of Berlin and Senator for Higher Education and Research), Prof. Dr. Heyo K. Kroemer (Chief Executive Officer of Charité), as well as the initiative's partners and other supporters - can be found here.

Under the leadership of Prof. Audebert and the study's first author, Prof. Dr. Dr. Martin Ebinger (Medical Director of the Medical Park Humboldtmühle Rehabilitation Hospital), the team studied cases of stroke emergencies which occurred in Berlin between February 2017 and May 2019. Whether a STEMO mobile stroke unit was dispatched was effectively decided by chance: if one was available within the relevant area, it was dispatched at the same time as the conventional ambulance, enabling the patient to receive treatment before their arrival in hospital. A STEMO mobile stroke unit was dispatched in 749 of a total of 1,543 cases analyzed as part of the study (49 percent). If no STEMO was available at the time of the emergency call, only a conventional ambulance was dispatched to ensure transport to a specialist hospital. In 794 cases (51 percent), patients were cared for within the conventional emergency medical system. Using a standardized protocol, the researchers then determined survival at three months post-stroke and the extent of any neurological impairment affecting the patients.

Results from their comparison of the STEMO and control groups were unequivocal. Not only did a greater number of STEMO patients receive thrombolysis (60 percent vs 48 percent in the control group), they received this treatment on average 20 minutes earlier than controls. After three months, approximately 7 percent of patients in the STEMO dispatch group had died. This figure compared with 9 percent in the conventional ambulance group. Similarly, while approximately 51 percent of patients in the STEMO group reported no stroke-related impairments in day-to-day functioning, the corresponding figure in the control group was only 42 percent. Patients in the STEMO group also scored significantly better on quality-of-life measures.

Women today represent two-thirds of all Canadian doctorates in archaeology, but only one-third of Canadian tenure-stream faculty. While men with Canadian PhDs have done well in securing tenure-track jobs in Canada over the past 15 years, women have not, according to a new study from McGill University. The current COVID-19 pandemic is likely to exacerbate these existing inequalities.

Published in American Antiquity, the study is the first to follow archaeologists from graduate school to faculty positions to determine when women are exiting the academic track. It's also the first to explore grant applications and the success rates of women in Canadian archaeology.

"A 'chilly climate' exists for women in academia. Subtle practices that stereotype, exclude, and devalue women, as well as inhospitable working environments, particularly for primary caregivers, are just some of the factors that could be contributing to attrition rates," says co-author Lisa Overholtzer, an Assistant Professor and William Dawson Scholar in the Department of Anthropology at McGill University.

According to the researchers, most women are exiting the academic track after significant investments of time and money in their doctoral training and before landing a tenure-track position. Over the last 10 years, women have earned 64 percent of the PhD degrees in archaeology in Canada but make up only 46 percent of assistant professors today.

"We might think that 46 percent sounds good - it's near 50 percent after all, but our expectations for gender ratios shouldn't be 50/50. They should reflect the proportions in candidate pools," says co-author Catherine Jalbert, an archaeologist with the Texas Historical Commission.

Gender gap in Canadian hiring

A significant drop in hiring coupled with the end of mandatory retirement has translated into fewer jobs at precisely the moment when women became most of the PhD recipients. Still, this does little to explain why women fill proportionately fewer of those jobs, say the researchers.

The situation looks even bleaker when tracing paths of Canadian doctorates compared to foreign doctorates into Canada. "While most of the men hired here have Canadian PhDs, most women hired in Canada are trained internationally," says Professor Overholtzer.

Only 4 out of 28 (14 percent) of assistant professor positions are currently filled by women who were trained in Canada. Of men who earned their PhDs in archaeology between 2003 and 2017, 36% are Canadian faculty members today, while that's true for only 12% of the women who trained alongside them.

In the United States, women with Canadian PhDs are hired at higher rates - even higher than men. However, the researchers note that the numbers don't make up for the gender gap in Canadian hiring. Neither does it appear that women archaeologists are choosing to work in other career tracks within the field in greater proportions.

Problems with academic research grants

The researchers found that women are just as likely to apply for federal research grants at each level. However, there are small but persistent gender gaps in success rates across all levels, from doctoral student to faculty member. This could be due to unequal mentorship or to a devaluing of the methods and research questions typically explored by women.

"Our findings have some direct implications for federal policy, like the eligibility of dependent care during fieldwork funded by the Social Sciences and Humanities Research Council," says Professor Overholtzer. Currently, childcare expenses are only eligible if a child is nursing or if a mother is a single parent. "We think that archaeology and other disciplines would be able to better retain women if they were able to cover childcare costs during fieldwork, regardless of the age of their children or their marital status," she says.

Potential solutions

Increased hiring will be essential in curbing gender inequality. But this will be a challenge post-COVID as many universities face hiring freezes and budget constraints. However, another potential avenue could be boosting the Canada Research Chairs program with high targets for women scientists, say the researchers.

"The onus is on us to scrutinize how we train and prepare women in the field. We also need to scrutinize our hiring practices to find out why women are hired less often, especially in Canada," Professor Overholtzer concludes.

The authors note that their analysis was limited to gender, but other inequities likely exist along intersecting factors of identity, including race, class, and parental status. As next steps, they plan to explore these, and assess the impact of the pandemic on career advancement, research productivity, and well-being among Canadian archaeologists.

Plastic, with its unabated global production, is a major and persistent contributor to environmental pollution. In fact, the accumulation of plastic debris in our environment is only expected to increase in the future. "Microplastics" (MP)--plastic debris

Scientists from Incheon National University, Korea, headed by Prof. Seung-Kyu Kim, now explore these questions in their latest study published in Journal of Hazardous Materials. "Most studies on MPs have focused on the marine environment, but substantial amounts of MPs can be generated in the agricultural environment via weathering and fragmentation of plastic products used in agricultural practices. We hoped to find out the amount of MPs in Korean agricultural soils and how they change according to different agricultural practices and environmental conditions," says Prof. Kim.

For their study, the scientists examined four soil types corresponding to different agricultural practices: soils from outside and inside a greenhouse (GS-out and GS-in, respectively), mulching (MS), and rice field soil (RS). Of these, the former three samples represented the use of polyethylene film, while the RS sample represented little to no use of plastic. To minimize the effect of non-agricultural sources of MP, scientists collected the samples from rural farmlands during the dry season. They only considered MPs in the size range of 0.1-5 and classified them as per their shapes: fragment (uneven), sheet (thin an even), spherule (round), and fiber (thread-like).

As expected, scientists found the highest average MP abundance in GS-in and GS-out (GS-in > GS-out), but surprisingly, they found the lowest MP content in MS rather than RS. Further, they found that among the different shapes of MPs, fragments dominated GS-in; fibers, GS-out and MS; and sheets, RS. Interestingly, all soils except GS-in had a major contribution from sheets, which hinted towards potential internal sources of fragment-type MPs within greenhouses.

Scientists also observed an interesting trend regarding MP size distribution in the soil samples. They found that, unlike GS-out, MS, and RS (which showed MP abundance only for a range of sizes), GS-in showed an increasing abundance for progressively smaller sizes. They attributed this to the absence of "environmental fate effect," causing the removal of MPs by surface-runoff, infiltration, and wind in the GS-in samples. Prof. Kim explains, "Contrary to previous studies which stress on MPs originating mostly from external sources, our study reveals that MPs in agricultural soil can come from external as well as internal sources, and that their concentration and sizes can be strongly affected by environmental conditions,"

These findings can contribute to an enhanced understanding of the role of agricultural environment as an MP source. Hopefully, assessing potential risks of MPs in agricultural soils and establishing efficient management strategies can help us to reduce the threat from MPs.