Culture

Low socioeconomic families - and particularly women - experienced increased financial hardship, food insecurity, domestic violence and mental health challenges during COVID-19 lockdown measures in Bangladesh, a new research study shows.

In the first study of its kind, Australian and Bangladeshi researchers documented the impacts of the COVID-19 pandemic and associated lockdown measures on the wellbeing of women and their families in rural Bangladesh. The study found that low socioeconomic families experienced a range of economic and mental health challenges during the two-month stay-at-home order, and women reported an increase in intimate partner violence.

The study, published today in The Lancet Global Health, suggests in the event of future public health lockdowns, the wellbeing of families - and particularly women - needs be actively addressed.

At a glance

Australian and Bangladeshi researchers, in the first study of its kind, joined forces to study the impact of lockdown measures in a rural community in Bangladesh.

Lockdown measures enforced due to the COVID-19 pandemic caused many families' incomes to drop below the international poverty line.

There was an increase in food insecurity, depression, anxiety and domestic violence during the lockdown period.

Devastating impacts of lockdown

Like many countries around the world, Bangladesh used stay-at-home (or lockdown) orders to limit the spread of COVID-19 in April and May 2020. Using an existing research network in Bangladesh, a collaborative team led by the Walter and Eliza Hall Institute and the International Centre for Diarrhoeal Diseases Research in Bangladesh was able to measure the impact of the lockdown on financial stability, food security, mental health and domestic violence in 2424 families in a rural Bangladesh community.

The impact of the lockdown on households was worrying, said Associate Professor Sant-Rayn Pasricha from the Walter and Eliza Hall Institute.

"While the lockdown was an essential public health measure to prevent the spread of COVID-19, we were concerned about the problems it could pose for the families in our study," Associate Professor Pasricha said.

"Comparing how families were faring before and during lockdown, we observed substantial financial and mental health pressures experienced during lockdown."

The study revealed 96 per cent of families experienced a reduction in employment and 91 per considered themselves to be financially unstable.

"During the lockdown, almost half (47 per cent) of families saw their earnings drop below the international poverty line of US$1.90 per day," Associate Professor Pasricha said.

"Seventy per cent experienced food insecurity, with one in six families running out of food, going hungry or missing meals."

The lockdown also had mental health impacts, with women showing an increase in depression symptoms, and 68 per cent of participants reporting their anxiety level had increased. Concerningly, among the women who reported emotional, physical or sexual violence from their intimate partner, more than half reported violence had increased since lockdown.

Families need more support

Associate Professor Pasricha said the study indicated the lockdown had unintended yet devastating outcomes for the families.

"Stay-at-home orders lasting more than two months, in a rural South Asian setting, have inflicted an enormous economic and psychosocial burden on women and their families," he said.

Associate Professor Pasricha said the results reflected similar studies that indicated the flow-on effect of stay-at-home orders to food security and nutrition would be experienced globally.

"The marked increase in severe food insecurity in our study population shows the impact of economic pressure on food access and supports modelling to suggest the pandemic could have a catastrophic effect on food security and consequently on nutrition worldwide.

"Our study, which is the first of its kind, highlights the need for wide-reaching welfare and other forms of financial support for families impacted by lockdown measures, not only for those on low incomes. Crucially, social support is needed to protect women's safety and it is essential that domestic violence intervention services remain accessible during lockdown.

Bangladeshi Principal investigator, Dr Jena Hamadani, International Centre for Diarrhoeal Diseases Research, Bangladesh, said she hoped the research would help inform governments about the need for welfare support for people in rural communities in low and middle income countries during lockdowns.

"We hope our findings will be valuable for public health officials, and will inform and improve future public health measures, should lockdowns continue," Dr Hamadani said.

Primates receive a lot of research attention and conservation funding compared to other taxonomic groups, owing largely to their anthropological significance and charisma. Yet, we remain unable to conserve them effectively. To date, about 60 percent of primate species are threatened with extinction and 75 percent have declining populations.

The authors of the new study ascribe this paradox to the severe lack of evidence for effective conservation of the world's primates. Compiled by a team of 59 primate researchers and practitioners, as well as scientists from the Conservation Evidence Initiative in Cambridge, the study examined roughly 13,000 primate studies. Only 80 of these studies investigated the effectiveness of primate conservation interventions, which is very few compared to other taxa. In addition, only 12 percent of threatened primates and only 14 percent of all primate species recognized today were covered by these intervention studies.

Intervention studies focused on large-bodied primates and Old World monkeys, particularly great apes, but left out entire families, such as tarsiers and night monkeys. "Whether a species was threatened or not played no significant role for the scientists in the choice of their studied species," said Dr Jessica Junker from iDiv, MLU and MPI-EVA, who led the research effort together with Dr Silviu Petrovan from the University of Cambridge's Department of Zoology. "We therefore lack the evidence-based information necessary to effectively protect and manage many vulnerable species."

In addition to the taxonomic biases, the authors also found that studies were biased towards specific geographic regions and interventions. More specifically, less than half (41 percent) of the 162 possible primate conservation interventions identified by primate experts were evaluated quantitatively.

Even those studies in which tests on the effectiveness of measures had been carried out failed in most cases (79 percent) to provide evidence of effective protection of primates. This was due to studies lacking quantitative data, difficulties in undertaking post-implementation monitoring of populations or individuals, or implementing several interventions at once. "The fact that so many measures are implemented without knowing whether they will work at all is an absolutely alarming result, considering the vulnerability of this group of species," said Petrovan. "Ideally, studies should identify the most effective interventions for all primate conservationists."

The problem of proving the effectiveness of primate protection measures is also due to the animals' survival and reproduction strategies. "Primates tend to occur at low densities, become relatively old and have few offspring, which means that generational changes take a relatively long time. In addition, their preferred habitat in the trees makes them difficult to count. This requires innovative methods and intense monitoring over long periods, specific knowledge and hard-to-obtain long-term funding," said Dr Hjalmar Kühl from iDiv and MPI EVA), senior author of the study.

Another disincentive for primate researchers to conduct evaluations for primate conservation actions is that publishing these can be extremely time- and resource-intensive and difficult to achieve in high-impact science journals, especially when they show that a conservation action was not effective.

The authors propose several actions to improve the evidence base for primate conservation, including raising resources for intervention-effectiveness testing and publication, developing guidelines for primate conservation interventions, shifting the research focus on threatened species, understudied regions and seeking long-term collaborations with stakeholders.

"The declines of many primate species highlight the urgent need for funding and swift action," said Kühl. "If we are to prevent imminent extinctions and ensure the survival of viable primate populations in the long term in a cost-effective manner, we need to adopt an evidence-based approach to primate conservation."

TORONTO - An international, first-of-its-kind cardiology trial used personalized genetic testing to reduce by 34 per cent the number of serious adverse events following balloon angioplasty, a treatment for the most common form of heart disease.

For patients undergoing percutaneous coronary intervention (PCI)--a non-surgical procedure where physicians inflate a balloon and place a metal stent in narrowed heart arteries to improve blood flow to the heart --the choice of antiplatelet therapy can be critical to post-treatment success, and to minimize the chance of heart attack or stroke.

The TAILOR-PCI trial, co-led by principal investigators Dr. Michael Farkouh, cardiologist and Multinational Clinical Trials Chair at the Peter Munk Cardiac Centre and Dr. Naveen Pereira, Professor of Medicine and cardiologist at Mayo Clinic, studied the effectiveness of genetic-guided therapy in patients that have had PCIs when compared to conventional therapy.

"The trial introduces the concept and validates the approach to personalized medicine when it comes to antiplatelet therapy, and therefore allows our physicians to potentially change their practice based on the needs of patients undergoing PCI," says Dr. Farkouh. "This will potentially inform the kinds of therapies patients with heart disease are prescribed after PCI worldwide."

Placement of a balloon and metal stent inside a heart artery can irritate the blood vessel and cause it to clot, which can block the artery from being treated. PCI patients are prescribed medications to prevent their blood from clotting - the most common medication used is clopidogrel, which stops blood platelets from sticking together and prevents clots from forming. However, in almost a third of all patients, the gene (CYP2C19) required to activate clopidogrel does not work.

As a result, patients with this genetic variant may be at a higher risk of experiencing adverse cardiovascular events, such as heart attack or stroke in the year following their procedure.

Current guidelines do not recommend genetic testing when prescribing clopidogrel, and the trial was designed to determine if genetic testing would decrease cardiovascular complications after PCI.

The Journal of the American Medical Association published the results of the TAILOR-PCI trial on August 25, 2020. The trial enrolled 5,302 patients treated for heart artery blockage with one or more stents and followed them for one year.

Half the group was tested for the CYP2C19 gene variation, and carriers (35%) were treated with the alternative anti-platelet medication, Ticagrelor. The remainder of the group was given Clopidogrel, as was the entire control group of patients who did not receive genetic testing before PCI.

Although the TAILOR-PCI trial did not meet its primary endpoint of demonstrating a 50 per cent reduction at one-year post-procedure, trends did show a benefit towards genetic testing with a 34 per cent reduction in serious adverse cardiovascular events.

"Although these results fell short of the effect size that we predicted, they nevertheless provide a signal that offers support for the benefit of genetically guided therapy, with approximately one third fewer adverse events in the patients who received genetically guided treatment compared with those who did not," says Dr. Pereira.

A post-hoc analysis of the trial also showed a nearly 80% reduction in the rate of adverse events in the first three months of treatment among patients who received genetically guided therapy compared with those who did not.

Since the study's design in 2012, the standard of care following PCIs has greatly improved. Drug-coated stents and other treatments have reduced the rate of adverse events for patients in a year, but at the same time made it more difficult for the trial to reach its goal.

The trial is currently undergoing an extended follow-up beyond the original 12-month period.

A research team from the Technical University of Munich (TUM) led by chemist Johannes Lercher has developed a synthesis process which drastically increases the activity of catalysts for the desulfurization of crude oil. The new process could perhaps also be used for catalysts in fuel cells.

Crude oil contains a great deal of sulfur. To turn the crude oil into fuel, the sulfur compounds must be removed using hydrogen. Experts call this process hydrotreating. The process is carried out using catalysts.

Under the leadership of Prof. Johannes Lercher and Dr Hui Shi, a team of researchers at the Professorship of Chemical Technology at the Technical University of Munich have now developed a process to increase the activity of these catalysts many times over by treating the catalytically active metal sulfides with concentrated hydrochloric acid beforehand.

Important for the environment

Hydrotreating is one of the most important catalytic processes - both with regard to the quantity of catalyst used and the quantity of processed raw material. With highly pressurized hydrogen, impurities such as sulfur or nitrogen compounds are removed from the crude oil as completely as possible.

"These kinds of impurities would later combust to form sulfur dioxide and nitrogen oxides, which would result in negative effects on the environment especially the air quality," says Manuel Wagenhofer, first author of the study. In addition, sulfur and nitrogen compounds would also damage precious metals in catalytic converters in modern vehicles, and drastically reduce their effectiveness.

An amazing effect of hydrochloric acid

The TUM chemists examined such mixed metal sulfide catalysts for their effectiveness in hydrotreating by first synthesizing nickel molybdenum sulfides over several process stages, and then treating them with acid.

"It was amazing how much adding concentrated hydrochloric acid increased the catalytic performance," says Wagenhofer. "Hydrochloric acid improves the accessibility of active centers in the catalysts by removing less active components, mainly nickel sulfides. Purer, and therefore more active, mixed metal sulfides are formed."

Great advantages for fundamental research

The TUM chemists' results are also very important for fundamental research. The purified mixed metal sulfides are also easier to examine, scientifically.

"For example, we were able to identify and quantify active centers on the catalysts that were treated in this way," explains Lercher. "This was only possible because the surface was no longer covered in nickel sulfide."

In principle, the acid treatment could apparently be used as an investigation instrument for a series of similar catalysts, to optimize these, for example, for use with oils from renewable raw materials which are to be transformed into climate-friendly fuels in the future via a refining process.

"If we understand mixed metal sulfide catalysts better, we can perhaps improve them considerably for use in other important fields of the future, such as water electrolysis or hydrogen fuel cells," says Johannes Lercher.

Tsukuba, Japan - Researchers at the University of Tsukuba have developed a new kind of color-shifting crystalline material that can be used to indicate the presence of water. The change in hue is dramatic enough to be gauged by the unaided human eye. This work could lead to the creation of highly sensitive "vapochromic" sensors that can show if a particular gas or water vapor is present without the need for external power.

Chemical sensors are important to many industrial processes. To ensure safety and efficiency, factories often need to be monitored for potentially toxic gasses or even excess humidity. Sensors for water vapor are particularly important, but may have limited lifetimes or require external power. To address this, scientists at the University of Tsukuba have invented a new crystalline material that changes color when exposed to water vapor. Inside the crystal, long branching molecules called dendrimers are held together by van der Waals forces.

"The aromatic carbazole dendrimers containing carbon rings are anchored to a dibenzophenazine core," explains senior author Professor Yohei Yamamoto. "Interestingly, even though van der Waals forces are usually considered to be relatively weak, the crystal stays together during operation."

The research team also extensively characterized the new material. In addition to studying the color in both the hydrated and dehydrated states using spectroscopy, the scientists used techniques including single-crystal and powder X-ray diffraction analysis, as well as thermogravimetric analysis. On the basis of the experimental results and theoretical density functional theory calculations, they were able to determine the molecular mechanism responsible for the different appearances under different water concentrations. The color-shifting properties of the crystal come from conformation changes in the dendrimers. Upon exposure to water vapor, the planes of the outermost carbazole units in the crystal twist simultaneously. This motion changes the energies of the electronic orbitals, which causes the electrons to absorb different colors of light.

"We believe that our findings will lead to the further exploration of van der Waals porous crystals, much like metal-organic frameworks that have found a place in chemistry," Professor Yamamoto says. "This work can lead to a new class of gas sensors that can work in difficult to reach locations, because they do not require external power."

Modern mechatronic devices, right from industrial machinery to robots, have seen a drastic increase in complexity and intricacy. With sophisticated functionalities being unlocked with each passing day, there has been an inevitable rise in the number of components that the devices need. And although these advancements are undeniably impressive, the sheer bulkiness and large number of components are a major hindrance to the "miniaturization" and cost-effectiveness of these devices.

But what if, instead of using multiple bulky components, we find a smarter way to build them? This is what scientists, including Prof Shingo Maeda, Dr Zebing Mao (Smart Materials Laboratory, Shibaura Institute of Technology) and Dr. Vito Caccuciolo (Soft Transducers Laboratory, Institute of Microengineering, École Polytechnique Fédérale de Lausanne), have worked on, in a recent study published in Scientific Reports. The scientists explored the possibility of various components of an electromechanical device--like the power supply, actuators, and control system--being reduced to a single piece of hydrogel. In doing this, they succeeded in creating a self-actuated microfluidic pump driven only by an oscillatory chemical reaction, which successfully produced "pressurized oil" (representing mechanical work). Prof Maeda, who led the study, says, "We propose a novel method to realize a simple pumping function using a single-component self-oscillating hydrogel and a membrane."

In their study, the scientists focused on a unique type of oscillatory chemical reaction that belongs to the "Belousov-Zhabotinsky" (BZ) class of reactions. Conventionally, a chemical reaction involves a reactant that gives rise to a product to reach a state of equilibrium. But, BZ reactions, which involve bromine and an oxidizing agent, produce a system that never reaches chemical equilibrium; instead, it goes back and forth between various states. Previously, researchers had observed that hydrogels and other polymers housing a BZ reaction (termed "BZ gels") were capable of autonomous motion because the reaction caused slight and periodic structural changes, thus showing a lot of potential in mechatronic applications. But, their practical use has been challenging until now. Prof Maeda explains, "Previously reported BZ gels showed very small displacement and were only tested while submerged inside chemical baths, which clearly limits their potential applications."

In this new study, the scientists overcame this hurdle using a new approach, which is much more promising thanks to an innovative implementation. Prof Maeda explains their methodology, "First, we produce BZ gels and pre-stretch them, which increases the mechanical work that can be extracted at each BZ cycle. Then, the whole gel and its surrounding chemical solution are completely encapsulated. Finally, the mechanical work produced by the swelling and contraction of the gel is transferred to an external oil through the deformation of a stretchable membrane." The result of this is a self-actuating pump solely driven by the oscillating reaction that can move fluids back and forth like an artificial "heart" for machines and produce mechanical work in the form of pressurized oil. The scientists tested the approach both virtually and experimentally, showing that the proposed concept holds potential.

This study sheds light on the fundamental physical mechanisms of BZ gels and indicates a way to improve their mechanical performance. It is an important step toward bridging the technological gap that exists for converting oscillating chemical energy into mechanical energy to power useful devices. Some noteworthy examples of feasible long-term applications of pumps made using BZ gels are in the field of microfluidics, including drug delivery systems, DNA microarrays for biomedical research, and many other biotechnological and nanotechnological tools. The self-actuating pump proposed by the scientists could act as a single-component power source in microfluidic systems, thereby simplifying their design, reducing their cost, and broadening their applicability.

The research team is optimistic about taking their work to the next level in the future, which will involve the optimization of their design through chemical and mechanical methods. This will be key for bringing forth a paradigm shift in the design of electromechanical devices by taking on a more bio-inspired turn. In this regard, Prof Maeda concludes, "Self-actuating pumps bode to break the wall of complexity faced by certain robotic systems with an increasing number of functions, enabling the development of truly smart multi-functional machines."

New light has been shed on a mysterious and long-standing conundrum at the very heart of our galaxy. The new work offers a potential solution to the so-called 'Galactic bar paradox', whereby different observations produce contradictory estimates of the motion of the central regions of the Milky Way. The results are published in Monthly Notices of the Royal Astronomical Society.

The majority of spiral galaxies, like our home the Milky Way, host a large bar-like structure of stars in their centre. Knowledge of the true bar size and rotational speed is crucial for understanding how galaxies form and evolve, as well as how they form similar bars throughout the Universe.

However our galaxy's bar size and rotational speed have been strongly contested in the last 5 years; while studies of the motions of stars near the Sun find a bar that is both fast and small, direct observations of the Galactic central region agree on one that is significantly slower and larger.

The new study, by an international team of scientists led by Tariq Hilmi of the University of Surrey and Ivan Minchev of the Leibniz Institute for Astrophysics Potsdam (AIP), suggests an insightful solution to this discrepancy. Analysing state-of-the-art galaxy formation simulations of the Milky Way, they show that both the bar's size and its rotational speed fluctuate rapidly in time, causing the bar to appear up to twice as long and rotate 20 percent faster at certain times.

The bar pulsations result from its regular encounters with the Galactic spiral arms, in what can be described as a "cosmic dance". As the bar and spiral arm approach each other, their mutual attraction due to gravity makes the bar slow down and the spiral speed up. Once connected, the two structures move as one and the bar appears much longer and slower than it actually is. As the dancers split apart, the bar speeds up while the spiral slows back down.

"The controversy about the Galactic bar can then be simply resolved if we happen to be living at a time when the bar and spiral are connected, giving the illusion of a large and slow bar," comments Dr Minchev. "However the motion of the stars near the Sun remains governed by the bar's true, much smaller nature, and so those observations appear contradictory."

Recent observations have confirmed that the inner Milky Way spiral arm is currently connected to the bar, which happens about once every 80 million years according to the simulations. Data from the forthcoming 3rd data release of the Gaia mission will be able to test this model further, and future missions will discover if the dance goes on in other galaxies across the Universe.

You might have heard the old proverb, "It takes a village to raise a child."

University of Cincinnati instructor Syn Yeo, PhD, thinks the same analogy applies when it comes to cells and the growth of cancer, particularly breast cancer.

In his recent study, published in the journal eLife, Yeo, research instructor in the department of cancer biology at the UC College of Medicine and co-lead author, says it can take cells in different forms or "life stages" to cause cancer to grow and spread.

"Our recent findings emphasize the need to account for the specific cell states that are present within a tumor," says Yeo, who is a member in the lab of Jun-Lin Guan, PhD, the Francis Brunning Endowed Chair and professor of cancer biology. "This could potentially help determine the combination of drugs that are required to eliminate all the cell states that are present to eliminate treatment resistance."

Yeo says that when it comes to breast cancers, it is known that cells within a tumor are varied.

"This diversity poses a problem to treating patients because particular subsets of tumor cells may be drug resistant and eventually lead to disease recurrence," he says. "One of the factors contributing to this diversity is the fact that tumor cells can exist in different cellular states, ranging from more stem-like cells that can become other cell types to more differentiated cells that have been coded to serve a purpose, or do a certain 'job' within the system.

"Cancer cells with stem-like properties are known to cause drug resistance, and they are generally seen as being at the top of the tumor hierarchy, like the kKing or queen of the village, with more differentiated tumor cells towards the bottom of the hierarchy, like the common townspeople."

In this study, researchers used breast cancer animal models to determine tumor hierarchies beyond "ruler" and "common people" cells, Yeo says. They identified and categorized singular cells which helped them understand each, individual cell's purpose. Yeo adds that bulk tumor cell analysis would have masked the cellular details.

"We were able to find a complex spectrum of cell states between different tumor types that can range from stem-cells to the 'beginner cells' to more differentiated cells," he says. "In our village [scenario], these would be the governors and mayors, followed by the common townspeople. Furthermore, depending on the lineage of the tumor, some may show a spectrum of cell states that are higher up in the hierarchy and vice versa.

"These findings are important because they show we need to know more about how these specific cell states contribute to tumor growth so we can target them with combination drug therapies, potentially helping more people who may otherwise experience drug resistance."

Tsukuba, Japan - Cardiovascular disease is the leading cause of death worldwide, killing nearly 18 million people annually, which is approximately the entire population of the New York metropolitan area. Now, researchers at the University of Tsukuba have shown that men bearing any or all of the major risk factors - hypertension, diabetes, and dyslipidemia - are more likely to have wives who suffer from the same diseases.

The World Health Organization lists ischemic heart disease and stroke as the number 1 and 2 killers; together they account for 85% of all cardiovascular-related deaths and have occupied top position for over three decades. Cardiovascular disease is both genetically and environmentally determined, with the latter exerting a greater influence. Hypertension, diabetes, and dyslipidemia are among the major risk factors and, though modifiable by drug therapy and behavioral change, are unfortunately becoming increasingly common.

In Japan, where over 83% of deaths occur after the age of 70, alleviating these chronic diseases will ensure that life is as healthy as it is long. Westernization of the diet, specifically reduced salt, has resulted in a drop in the incidence of hypertension, but causes increased obesity, diabetes, and hyperlipidemia.

"Married couples share food preferences and meal patterns, lifestyle with regard to levels of activity, attitudes to physical exercise, and usage of cigarettes and alcohol," explains Professor Takehiro Sugiyama. "Concordant disease patterns within couples may refer to risks of chronic diseases that could be reduced by changing daily habits, rather than unmodifiable genetic risks."

The researchers conducted a cross-sectional study of 86,941 married couples over the age of 40, across Japan. Using logistic regression, they modeled husbands undergoing treatment for hypertension, diabetes, and dyslipidemia as the exposure and their wives undergoing therapy for the same disease as the outcome. Features that could skew the results such as residence, education, age, habits, expenditure, and access to healthcare and health groups were also factored in to determine the degree of spousal concordance. Because spouses often influence personal habits, the researchers also evaluated models excluding the wife's smoking and alcohol history. The findings were clear: wives were significantly more likely to be receiving therapy for the same diseases as their husbands.

Professor Nanako Tamiya, senior author, highlights their inferences. "Our findings stress that healthcare professionals should target not only patients' blood-relatives, but also their spouses. Medical information should include the partner's data. In addition to optimizing individual therapy, family-based interventions are needed. Couples too need to appreciate their influence on each other's health patterns."

Scientists have discovered a novel anti-aging defence in the brain cells of adult fruit flies: producing extra copies of the genome, according to a new study published today in eLife.

The findings could help explain how the brain, which rarely produces new cells, is able to cope with the accumulation of cell damage over time and prevent excess cell loss during aging. They may also help scientists answer questions about human age-related brain diseases.

Most cells have two copies of each chromosome, one from each parent. This provides each cell with two complete copies of DNA, referred to as the genome. But some cells accumulate extra copies of chromosomes, although how and why they do this is not entirely clear. Some scientists have suggested that excess chromosomes might lead to age-related brain diseases.

"The brain of the fruit fly Drosophila melanogaster is an ideal model for studying age-related changes in the brain because the fly has a relatively short lifespan, its brain cells rarely multiply, and we have excellent tools for manipulating fly genetics," says lead author Shyama Nandakumar, a doctoral student in the department of Molecular, Cellular, and Developmental Biology at the University of Michigan, Ann Arbor, US.

In the study, Nandakumar and colleagues examined adult fly brain cells and found that some accumulate extra copies of their genome, especially in parts of the brain responsible for vision - the region of the brain which shows more DNA damage with age.

Next, they subjected fly brain cells to oxidative stress or ultraviolet radiation, which damage DNA and can cause cell death. They found that this exposure increased the production of extra copies of chromosomes in the cells, and the cells were less likely to die as a result of the damage. "These data suggest that cells with extra copies of the genome are more resistant to cell death and may serve a beneficial or protective role in the aging brain," Nandakumar explains.

Previous studies have found that patients with early stages of Alzheimer's disease have extra chromosomes in their brain cells than people of the same age who do not have the condition. This has led scientists to question whether accumulating extra chromosomes leads to brain cell death and brain disease.

"Our study suggests that the production of extra copies of chromosomes might actually be a normal response to the accumulation of age-related damage in flies and may even help protect against cell death," concludes senior author Laura Buttitta, Associate Professor of Molecular, Cellular and Developmental Biology at the University of Michigan. "Further studies are now needed to determine if this is also true in humans."

New insight on how zebrafish achieve near-optimal foraging efficiency and fairness among groups has been published today in the open-access journal eLife.

The findings, based on analysis of the joint swimming patterns of individual zebrafish and groups, and detailed mathematical models of their behaviour, suggest that specialised social interactions allow the animals to forage efficiently and result in more equal distribution of food among group members.

Living in a group has clear benefits, including the sharing of responsibilities and resources. Understanding the interactions among individuals that give rise to group behaviour is therefore central to studying and analysing collective behaviour in animal groups and other biological systems.

"In real-world situations, animals are likely to encounter several food sources or threats, where maintaining a tight group may not be beneficial for all group members," explains lead author Roy Harpaz, who was a PhD student at the Weizmann Institute of Science, Israel, at the time the study was carried out, and is now Postdoctoral Fellow at Harvard University, Cambridge, US. "Indeed, schooling and shoaling species have been shown to disperse when confronted with distributed resources. We aimed to characterise group foraging in complex environments and map the functional interactions among group members."

Harpaz and his PhD advisor, Elad Schneidman of the Weizmann Institute, studied free foraging by groups of adult zebrafish in an open arena. They tracked the foraging behaviours of single adult zebrafish and of groups of three or six fish in a large circular arena with shallow water, where small food flakes were scattered on the surface. Tracking these activities revealed that fish picked up on their shoal mates' swimming maneuvers which indicated the presence of food, and responded by swimming to these locations.

The team then compared the predictive power of a family of mathematical models, based on inferred functional and social interactions between zebrafish. The model which accurately described individual and group foraging behaviours suggests that the interactions among fish allow them to combine individual and social information to achieve near-optimal foraging efficiency and promote more equal food intake within groups.

"Of the different social models we tested, only the one based on the social interactions we inferred from observing real fish results in improved efficiency and equality," Harpaz says. "Also, our model shows that the interactions that would maximise efficiency in these social foraging models depend on group size, but not necessarily on food distribution. We therefore hypothesise that fish adaptively pick the subgroup of neighbours they 'listen to' to determine their own behaviour."

"Building accurate models of individual behaviour of groups of fish allowed us to infer the details of effective social interactions among them and reveal a highly efficient and robust foraging strategy," concludes senior author Elad Schneidman. "This work is an example of the power of using detailed analyses of individuals in real groups to build data-driven models of social interactions, and of using these models to link the actions of individual animals to the collective behaviour of a group."

New machine learning algorithm designed by astronomers and computer scientists from University of Warwick confirms new exoplanets in telescope data

Sky surveys find thousands of planet candidates, and astronomers have to separate the true planets from fake ones

Algorithm was trained to distinguish between signs of real planets and false positives

New technique is faster than previous techniques, can be automated, and improved with further training

Fifty potential planets have had their existence confirmed by a new machine learning algorithm developed by University of Warwick scientists.

For the first time, astronomers have used a process based on machine learning, a form of artificial intelligence, to analyse a sample of potential planets and determine which ones are real and which are 'fakes', or false positives, calculating the probability of each candidate to be a true planet.

Their results are reported in a new study published in the Monthly Notices of the Royal Astronomical Society, where they also perform the first large scale comparison of such planet validation techniques. Their conclusions make the case for using multiple validation techniques, including their machine learning algorithm, when statistically confirming future exoplanet discoveries.

Many exoplanet surveys search through huge amounts of data from telescopes for the signs of planets passing between the telescope and their star, known as transiting. This results in a telltale dip in light from the star that the telescope detects, but it could also be caused by a binary star system, interference from an object in the background, or even slight errors in the camera. These false positives can be sifted out in a planetary validation process.

Researchers from Warwick's Departments of Physics and Computer Science, as well as The Alan Turing Institute, built a machine learning based algorithm that can separate out real planets from fake ones in the large samples of thousands of candidates found by telescope missions such as NASA's Kepler and TESS.

It was trained to recognise real planets using two large samples of confirmed planets and false positives from the now retired Kepler mission. The researchers then used the algorithm on a dataset of still unconfirmed planetary candidates from Kepler, resulting in fifty new confirmed planets and the first to be validated by machine learning. Previous machine learning techniques have ranked candidates, but never determined the probability that a candidate was a true planet by themselves, a required step for planet validation.

Those fifty planets range from worlds as large as Neptune to smaller than the Earth, with orbits as long as 200 days to as little as a single day. By confirming that these fifty planets are real, astronomers can now prioritise these for further observations with dedicated telescopes.

Dr David Armstrong, from the University of Warwick Department of Physics, said: "The algorithm we have developed lets us take fifty candidates across the threshold for planet validation, upgrading them to real planets. We hope to apply this technique to large samples of candidates from current and future missions like TESS and PLATO.

"In terms of planet validation, no-one has used a machine learning technique before. Machine learning has been used for ranking planetary candidates but never in a probabilistic framework, which is what you need to truly validate a planet. Rather than saying which candidates are more likely to be planets, we can now say what the precise statistical likelihood is. Where there is less than a 1% chance of a candidate being a false positive, it is considered a validated planet."

Dr Theo Damoulas from the University of Warwick Department of Computer Science, and Deputy Director, Data Centric Engineering and Turing Fellow at The Alan Turing Institute, said: "Probabilistic approaches to statistical machine learning are especially suited for an exciting problem like this in astrophysics that requires incorporation of prior knowledge - from experts like Dr Armstrong - and quantification of uncertainty in predictions. A prime example when the additional computational complexity of probabilistic methods pays off significantly."

Once built and trained the algorithm is faster than existing techniques and can be completely automated, making it ideal for analysing the potentially thousands of planetary candidates observed in current surveys like TESS. The researchers argue that it should be one of the tools to be collectively used to validate planets in future.

Dr Armstrong adds: "Almost 30% of the known planets to date have been validated using just one method, and that's not ideal. Developing new methods for validation is desirable for that reason alone. But machine learning also lets us do it very quickly and prioritise candidates much faster.

"We still have to spend time training the algorithm, but once that is done it becomes much easier to apply it to future candidates. You can also incorporate new discoveries to progressively improve it.

"A survey like TESS is predicted to have tens of thousands of planetary candidates and it is ideal to be able to analyse them all consistently. Fast, automated systems like this that can take us all the way to validated planets in fewer steps let us do that efficiently."

The last decade has seen rapid development in the archaeology of Saudi Arabia. Recent discoveries range from early hominin sites hundreds of thousands of years old to sites just a few hundred years old. One enigmatic aspect of the archaeological record of western Arabia is the presence of millions of stone structures, where people have piled rocks to make different kinds of structures, ranging from burial tombs to hunting traps. One enigmatic form consists of vast rectangular shapes. Archaeologists working with the AlUla Royal Commission gave these the name 'mustatils,' which is Arabic for rectangle.

Mustatils only occur in northwest Saudi Arabia. They had been previously recognized from satellite imagery and as they were often covered by younger structures, it had been speculated that they might be ancient, perhaps extending back to the Neolithic.

In this new article led by Dr Huw Groucutt (group leader of the Extreme Events Research Group which is a Max Planck group spanning the Max Planck Institutes for Chemical Ecology, the Science of Human History, and Biogeochemistry) an international team of researchers under the auspices of the Green Arabia Project (a large project headed by Prof. Michael Petraglia from the Department of Archaeology at the Max Planck Institute for the Science of Human History and the Saudi Ministry for Tourism as well as collaborators from multiple Saudi and international institutions) conducted the first every detailed study of mustatils. Through a mixture of field survey and analyzing satellite imagery, the team have considerably extended knowledge on these enigmatic stone structures.

More than one hundred new mustatils have been identified around the southern margins of the Nefud Desert, between the cities of Ha'il and Tayma, joining the hundreds previously identified from studies of Google Earth imagery, particularly in the Khaybar area. The team found that these structures typically consist of two large platforms, connected by parallel long walls, sometimes extending over 600 meters in length. The long walls are very low, had no obvious openings and are located in diverse landscape settings. It is also interesting that little in the way of other archaeology - such as stone tools - was found around the mustatils. Together these factors suggest that the structures were not simply utilitarian entities for something like water or animal storage.

At one locality the team were able to date the construction of a mustatil to 7000 thousand years ago, by radiocarbon dating charcoal from inside one of the platforms. An assemblage of animal bones was also recovered, which included both wild animals and possibly domestic cattle, although it is possible that the latter are wild auroch. At another mustatil the team found a rock with a geometric pattern painted onto it.

"Our interpretation of mustatils is that they are ritual sites, where groups of people met to perform some kind of currently unknown social activities," says Groucutt. "Perhaps they were sites of animal sacrifices, or feasts."

The fact that sometimes several of the structures were built right next to each other may suggest that the very act of their construction was a kind of social bonding exercise. Northern Arabia 7,000 years ago was very different to today. Rainfall was higher, so much of the area was covered by grassland and there were scattered lakes. Pastoralist groups thrived in this environment, yet it would have been a challenging place to live, with droughts a constant risk.

The team's hypothesis is that mustatils were built as a social mechanism to live in this challenging landscape. They may not be the oldest buildings in the world, but they are on a uniquely large scale for this early period, more than two thousand years before pyramids began to be constructed in Egypt. Mustatils offer fascinating insights into how humans have lived in challenging environments and future studies promise to be extremely useful at understanding these ancient societies.

In this image, made with the National Science Foundation's Very Long Baseline Array (VLBA), young, radio-emitting jets of material emerge from the core of an elliptical galaxy some 500 million light-years from Earth. After NASA's Fermi Gamma-ray Space Telescope detected high-energy gamma rays coming from the object, scientists used the VLBA to make high-resolution images of the galaxy, dubbed TXS 0128+554.

This image is a composite of six VLBA images made at observing frequencies ranging from 2.2 GigaHertz (GHz) to 22.2 GHz. The broad lobes on either side of the bright core are the result of jet activity that began roughly 80 years ago. The gap between these lobes and the central region indicates, the scientists said, that the jet activity stopped sometime after that, then resumed about 10 years ago.

"These are among the youngest known jets in such systems, and only a handful are known to emit gamma-rays," said Matthew Lister, of Purdue University.

The bright edges of the lobes are where the ejected material, moving at about a third the speed of light, impacted material within the galaxy. The bright emitting areas total about 35 light-years across, and are at the core of the galaxy, where a supermassive black hole about one million times the mass of the Sun resides.

Not so long ago, astronomers mapped a galaxy far, far away using radio waves and found it has a strikingly familiar shape. In the process, they discovered the object, called TXS 0128+554, experienced two powerful bouts of activity in the last century.

Around five years ago, NASA's Fermi Gamma-ray Space Telescope reported that TXS 0128+554 (TXS 0128 for short) is a faint source of gamma rays, the highest-energy form of light. Scientists have since taken a closer look using the Very Long Baseline Array (VLBA) and NASA's Chandra X-ray Observatory.

"After the Fermi announcement, we zoomed in a million times closer on the galaxy using the VLBA's radio antennas and charted its shape over time," said Matthew Lister, a professor of physics and astronomy at Purdue University in West Lafayette, Indiana. "The first time I saw the results, I immediately thought it looked like Darth Vader's TIE fighter spacecraft from 'Star Wars: A New Hope.' That was a fun surprise, but its appearance at different radio frequencies also helped us learn more about how active galaxies can change dramatically on decade time scales."

A paper describing the findings, led by Lister, was published in the Aug. 25 issue of the Astrophysical Journal and is now available online.

TXS 0128 lies 500 million light-years away in the constellation Cassiopeia, anchored by a supermassive black hole around 1 billion times the Sun's mass. It's classified as an active galaxy, which means all its stars together can't account for the amount of light it emits.

An active galaxy's extra energy includes excess radio, X-ray, and gamma-ray light. Scientists think this emission arises from regions near its central black hole, where a swirling disk of gas and dust accumulates and heats up because of gravitational and frictional forces.

Around one-tenth of active galaxies produce a pair of jets, beams of high-energy particles traveling at nearly the speed of light in opposite directions. Astrophysicists think these jets produce gamma rays. In some cases, collisions with tenuous intergalactic gas eventually slow and halt the outward motion of jet particles, and the material starts to flow back toward the galaxy's center. This results in broad regions, or lobes, filled with fast-moving particles spiraling around magnetic fields. The particle interactions create bright radio emission.

Fermi has identified over 3,000 active galaxies using its Large Area Telescope, which surveys the entire sky every three hours. Nearly all of them are aligned so that one jet points almost directly at Earth, which boosts their signals. TXS 0128, however, is around 100,000 times less powerful than most of them. In fact, even though it's relatively nearby, Fermi needed to accumulate five years of data from the galaxy before reporting it as a gamma-ray source in 2015.

Researchers then added the galaxy to a long-running survey conducted by the VLBA, a network of radio antennas operated by the National Radio Astronomy Observatory stretching from Hawaii to the U.S. Virgin Islands.

The array's measurements provide a detailed map of TXS 0128 at different radio frequencies. The radio structure they revealed spans 35 light-years across and tilts about 50 degrees out of our line of sight. This angle means the jets aren't pointed directly at us and may explain why the galaxy is so dim in gamma rays.

"The real-world universe is three-dimensional, but when we look out into space, we usually only see two dimensions," said Daniel Homan, a co-author and professor of astronomy at Denison University in Granville, Ohio. "In this case, we're lucky because the galaxy is angled in such a way, from our perspective, that the light from the farther lobe travels dozens more light-years to reach us than the light from the nearer one. This means we're seeing the farther lobe at an earlier point in its evolution."

If the galaxy was aligned so the jets and lobes were perpendicular to our line of sight, all the light would reach Earth at the same time. We would see both sides at the same stage of development, which they are in reality.

The galaxy's apparent shape depends on the radio frequency used. At 2.3 gigahertz (GHz), about 21 times greater than the maximum broadcast frequency of FM radio, it looks like an amorphous blob. The TIE fighter shape emerges at 6.6 GHz. Then, at 15.4 GHz, a clear gap in the radio emission appears between the galaxy's core and its lobes.

Lister's team suspects a lull in TXS 0128's activity created this gap. The galaxy's jets appear to have started around 90 years ago, as observed from Earth, and then stopped about 50 years later, leaving behind the unconnected lobes. Then, roughly a decade ago, the jets turned on again, producing the emission seen closer to the core. What caused the sudden onset of these active periods remains unclear.

The radio emission also sheds light on the location of the galaxy's gamma-ray signal. Many theorists predicted that young, radio-bright active galaxies produce gamma rays when their jets collide with intergalactic gas. But in TXS 0128's case, at least, the particles in the lobes don't produce enough combined energy to generate the detected gamma rays. Instead, Lister's team thinks the galaxy's jets produce gamma rays closer to the core, like the majority of active galaxies Fermi sees.

The team observed the galaxy in X-rays using Chandra, looking for evidence of an enveloping cocoon of ionized gas. While their measurements couldn't confirm the presence or absence of a cocoon, there has been evidence for such structures in other active galaxies, like Cygnus A. The observations do indicate the galaxy has a large amount of dust and gas surrounding its core, which is consistent with a highly inclined viewing angle.

"This galaxy reminds us of the importance of multiwavelength observations, looking at objects across a wide range of the electromagnetic spectrum," said Elizabeth Hays, the Fermi project scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "Fermi, the VLBA, and Chandra each add a layer to our growing picture of this object, revealing their own surprises."

The Fermi Gamma-ray Space Telescope is an astrophysics and particle physics partnership managed by NASA's Goddard Space Flight Center in Greenbelt, Maryland. Fermi was developed in collaboration with the U.S. Department of Energy, with important contributions from academic institutions and partners in France, Germany, Italy, Japan, Sweden, and the United States.

NASA's Marshall Space Flight Center manages the Chandra program. The Smithsonian Astrophysical Observatory's Chandra X-ray Center controls science and flight operations from Cambridge and Burlington, Massachusetts.