Tech

Solar cells have come a long way, but inexpensive, thin film solar cells are still far behind more expensive, crystalline solar cells in efficiency. Now, a team of researchers suggests that using two thin films of different materials may be the way to go to create affordable, thin film cells with about 34% efficiency.

"Ten years ago I knew very little about solar cells, but it became clear to me they were very important," said Akhlesh Lakhtakia, Evan Pugh University Professor and Charles Godfrey Binder Professor of Engineering Science and Mechanics, Penn State.

Investigating the field, he found that researchers approached solar cells from two sides, the optical side -- looking on how the sun's light is collected -- and the electrical side -- looking at how the collected sunlight is converted into electricity. Optical researchers strive to optimize light capture, while electrical researchers strive to optimize conversion to electricity, both sides simplifying the other.

"I decided to create a model in which both electrical and optical aspects will be treated equally," said Lakhtakia. "We needed to increase actual efficiency, because if the efficiency of a cell is less than 30% it isn't going to make a difference." The researchers report their results in a recent issue of Applied Physics Letters.

Lakhtakia is a theoretician. He does not make thin films in a laboratory, but creates mathematical models to test the possibilities of configurations and materials so that others can test the results. The problem, he said, was that the mathematical structure of optimizing the optical and the electrical are very different.

Solar cells appear to be simple devices, he explained. A clear top layer allows sunlight to fall on an energy conversion layer. The material chosen to convert the energy, absorbs the light and produces streams of negatively charged electrons and positively charged holes moving in opposite directions. The differently charged particles get transferred to a top contact layer and a bottom contact layer that channel the electricity out of the cell for use. The amount of energy a cell can produce depends on the amount of sunlight collected and the ability of the conversion layer. Different materials react to and convert different wavelengths of light.

"I realized that to increase efficiency we had to absorb more light," said Lakhtakia. "To do that we had to make the absorbent layer nonhomogeneous in a special way."

That special way was to use two different absorbent materials in two different thin films. The researchers chose commercially available CIGS -- copper indium gallium diselenide -- and CZTSSe -- copper zinc tin sulfur selenide-- for the layers. By itself, CIGS's efficiency is about 20% and CZTSSe's is about 11%.

These two materials work in a solar cell because the structure of both materials is the same. They have roughly the same lattice structure, so they can be grown one on top of the other, and they absorb different frequencies of the spectrum so they should increase efficiency, according to Lakhtakia.

"It was amazing," said Lakhtakia. "Together they produced a solar cell with 34% efficiency. This creates a new solar cell architecture -- layer upon layer. Others who can actually make solar cells can find other formulations of layers and perhaps do better."

According to the researchers, the next step is to create these experimentally and see what the options are to get the final, best answers.

Lung cancer is the leading cancer killer in the U.S. It is often missed in its earlier stages, and while recent imaging advances have enabled earlier detection, there are still no targeted treatments for early-stage lung cancers. New research from Boston Children's Hospital, in collaboration with Boston University and UCLA, provides an accelerated platform for identifying and testing potential treatments: "organoids" created from lung cells.

As reported September 4 in Cell Stem Cell, the organoids enabled the researchers to track one common, hard-to-treat lung tumor -- adenocarcinoma driven by mutation in the KRAS gene -- from its origins, capturing the molecular changes that took place as it progressed.

The research team, led by Carla Kim, PhD, of Boston Children's Stem Cell Program, used four parallel models of early lung cancer: tumor samples from patients with early (stage 1A) lung cancer, genetically engineered mouse models, and lung organoids derived from either mouse lung stem cells or from lung cells created from human induced pluripotent stem cells.

"We know very little about the early events that transform a normal lung epithelial cell into a cancer cell," says Kim, co-senior author on the paper with Jane Yanagawa, MD, of UCLA and Darrell Kotton, MD, of the Boston University School of Medicine. "In this study, we were able to use early-stage samples from lung cancer patients to show that our organoids truly mimic what happens in patients at the very early stages. We can see changes in the organoids within seven days that can take months to see in mice and even longer, probably years, in patients."

Tracking an unfolding lung cancer

The researchers introduced the cancer-initiating KRAS mutation into the lung organoids' alveolar progenitor cells. They then used single-cell RNA sequencing to see what genes turned on, or expressed, as a result. These studies revealed reduced expression of genes that are markers of mature lung alveolar cells, and increased expression of genes involved in early lung development -- known markers of cancer progression. Studies in mice and in the patient tumor samples mirrored findings in the organoids.

"KRAS-mutant tumors are usually already resistant to therapy by the time they are diagnosed," notes Kim. "These studies lay a groundwork for finding new therapeutic avenues in the future when an early-stage lung cancer is detected."

Although this study looked at KRAS-driven lung cancer, the researchers believe that the organoid approach could facilitate the study of other kinds of cancer, including testing of candidate drugs.

"The collaborating teams really made progress together in understanding a stage of lung cancer that has been very tough to study in humans," says Kotton. "We hope these new human and lung organoid models of early lung cancer formation will now serve as powerful drug development platforms."

ADELPHI, Md -- Army research has extended the state-of-the-art in autonomy by providing a more complete picture of how actions and nonverbal signals contribute to promoting cooperation. Researchers suggested guidelines for designing autonomous machines such as robots, self-driving cars, drones and personal assistants that will effectively collaborate with Soldiers.

Dr. Celso de Melo, computer scientist with the U.S. Army Combat Capabilities Development Command's Army Research Laboratory at CCDC ARL West in Playa Vista, California, in collaboration with Dr. Kazunori Teradafrom Gifu University in Japan, recently published a paper in Scientific Reports where they show that emotion expressions can shape cooperation.

Autonomous machines that act on people's behalf are poised to become pervasive in society, de Melo said; however, for these machines to succeed and be adopted, it is essential that people are able to trust and cooperate with them.

"Human cooperation is paradoxical," de Melo said. "An individual is better off being a free rider, while everyone else cooperates; however, if everyone thought like that, cooperation would never happen. Yet, humans often cooperate. This research aims to understand the mechanisms that promote cooperation with a particular focus on the influence of strategy and signaling."

Strategy defines how individuals act in one-shot or repeated interaction. For instance, tit-for-tat is a simple strategy that specifies that the individual should act as his/her counterpart acted in the previous interaction.

Signaling refers to communication that may occur between individuals, which could be verbal (e.g., natural language conversation) and nonverbal (e.g., emotion expressions).

This research effort, which supports the Next Generation Combat Vehicle Army Modernization Priority and the Army Priority Research Area for Autonomy, aims to apply this insight in the development of intelligent autonomous systems that promote cooperation with Soldiers and successfully operate in hybrid teams to accomplish a mission.

"We show that emotion expressions can shape cooperation," de Melo said. "For instance, smiling after mutual cooperation encourages more cooperation; however, smiling after exploiting others - which is the most profitable outcome for the self - hinders cooperation."

The effect of emotion expressions is moderated by strategy, he said. People will only process and be influenced by emotion expressions if the counterpart's actions are insufficient to reveal the counterpart's intentions.

For example, when the counterpart acts very competitively, people simply ignore-and even mistrust-the counterpart's emotion displays.

"Our research provides novel insight into the combined effects of strategy and emotion expressions on cooperation," de Melo said. "It has important practical application for the design of autonomous systems, suggesting that a proper combination of action and emotion displays can maximize cooperation from Soldiers. Emotion expression in these systems could be implemented in a variety of ways, including via text, voice, and nonverbally through (virtual or robotic) bodies."

According to de Melo, the team is very optimistic that future Soldiers will benefit from research such as this as it sheds light on the mechanisms of cooperation.

"This insight will be critical for the development of socially intelligent autonomous machines, capable of acting and communicating nonverbally with the Soldier," he said. "As an Army researcher, I am excited to contribute to this research as I believe it has the potential to greatly enhance human-agent teaming in the Army of the future."

The next steps for this research include pursuing further understanding of the role of nonverbal signaling and strategy in promoting cooperation and identifying creative ways to apply this insight on a variety of autonomous systems that have different affordances for acting and communicating with the Soldier.

Every tree, even an evergreen, can be an air quality monitor. That's the conclusion of researchers at the University of Utah who measured the magnetism of particulate matter on the needles of evergreen trees on the U campus. That measurement, they found, correlated to general air quality, suggesting that analysis of the needles--a relatively simple and low-cost process--could provide a high-resolution, year-round picture of air quality.

"Wherever you have a tree you have a data point," says Grant Rea-Downing, a doctoral student in geology and geophysics. "A tree doesn't cost $250 to deploy. We'll be able to map particulate matter distributions at a very high resolution for very little cost."

The results are published in GeoHealth.

How magnetic particles end up on leaves

Rea-Downing and his colleagues--associate professor Pete Lippert and fellow graduate students Courtney Wagner and Brendon Quirk--are all geoscientists in the Department of Geology and Geophysics whose regular research is on a much different scale than pine needles.

"Day to day," Lippert says, "we move mountains and close ocean basins by using the magnetism of rocks to figure out the geography of former continents."

In a course titled "The Magnetic Earth," Lippert introduced Rea-Downing, Wagner and Quirk to papers by U.K. researchers who measured the magnetism of deciduous leaves to assess air quality. "I knew the students would kind of have their minds blown by what the study showed, and what the implications of the findings were," Lippert says.

Particulate matter in the air comes from many sources, including natural windblown dust, brake dust and the byproduct of burning solid or fossil fuel.

"That's stuff in the air," Lippert says, "and it's got to come out sometime."

When it falls out of the air some of it, of course, falls on tree leaves and evergreen needles. Some of the particles contain iron, with enough to be detectable by the kind of high-precision magnetometers that Lippert uses in his geological work. The iron-bearing particulate matter in the air can be too small to see, but magnetism, he says, is a way to see the unseen.

The papers made an impression on Rea-Downing, who saw Salt Lake City's air quality in stark contrast to the normally clean air of his native coastal California. He could easily apply the method in Lippert's research lab.

"The kind of hill to climb to do this was actually quite flat," he says. "We have trees outside, we have seasonally bad air quality and we have a fully equipped paleomagnetic lab, which means that I literally just had to walk outside and pull some leaves off some trees and stick them in a magnetometer."

"We're not the first to explore the magnetism of pine needles to monitor air quality," Lippert says, "but no one had tried this to study winter inversions in the basins of the American West."

With financial support from the U's Global Change and Sustainability Center, the researchers went to work.

Sylvan sentinels

The team selected four Austrian pine trees on the U campus to sample. Three of the trees were in a line perpendicular to North Campus Drive, a heavily used campus artery, with each tree successively farther from the roadway. The fourth was near the Union building, away from traffic. They collected pine needles twice: once in June 2017 after a summer of relatively good air and again in December 2017 during some of that winter's worst air quality.

With her particulate-matter-filtering dust mask on, Wagner collected the December samples in what she described as a "freezing death fog," as a temperature inversion throughout the valley had led to a thick yellowish fog and frost on the pine needles. Back in the lab, the team carefully cut the needles into short segments using ceramic scissors to avoid any metals contamination and put them in the magnetometers.

One of their experiments revealed that the magnetization of the December needles was nearly three times higher than the June needles. Another magnetic experiment, conducted at superlow temperatures, suggested the iron-bearing particles deposited during the inversion are extremely small (some as small as 1/5000 the width of a human hair) and found that they're composed of magnetite, an iron mineral that, as its name suggests, is naturally magnetic. The team also examined the needles under an electron microscope and confirmed that the December needles were significantly dirtier. The concentration, size and composition of the particles have all been linked by other studies to the health risks of air pollution.

They also looked at the elements present in the particulates. The amounts of iron in the dust correlated with amounts of other elements like titanium, vanadium and zirconium, "and a variety of other things that are associated with brake dust or fossil fuel combustion," Lippert says.

Other elements in the particulates were associated with catalytic converters, he says, which use chemical catalysts to detoxify exhaust. "And those concentrations, no surprise, are highest near the roadside."

Comparing the trees at various distances from the roadway showed a drop-off in the concentration of magnetic particles over a distance of 50 to 150 feet. That may be due to distance from the cars, the researchers say, but also possibly to elevation, as the transect of trees went up a slight hill.

Artificial pine

Now the team has joined forces with atmospheric scientist Gannet Hallar and chemical engineer Kerry Kelly to explore other questions that the study raised. They developed a new kind of passive air monitor--a 3-D printed, artificial pine branch with needles to catch particulates. The artificial needles are installed alongside natural needles and can serve as an experimental platform to more clearly understand how and when particles settle on evergreen needles, results they can compare directly to measurements of particle distributions measured by equipment in Hallar's and Kelly's labs.

"If we get a strong rain we can go and collect before and after that rain and see if this signal is just being washed away every time you have a rain event," Rea-Downing says. "Or are the biological needles actually absorbing material and actually holding onto that signal for longer than the synthetic needles?"

With every tree as a potential data point, pine needle analysis could give a more comprehensive insight into the what, when and why of air pollution in urban areas, showing variation in air quality on the scale of tens of feet. The analysis is straightforward and inexpensive, Lippert says.

"We have a lot of trees out on the landscape already," Lippert says. "They're a pretty low cost. So this democratizes our ability to monitor air pollution across the valley. This is easily exportable to any community. It allows us to do more with less, or that's our hope."

Migrants arrested for tending plants in the flats, houses and attics where cannabis is grown in bulk are often victims of trafficking and "debt bondage" - yet many are not recognised as such by police, according to a new study.

Research from Cambridge criminologists suggests that those charged with drug cultivation have often been forced into illegal work as a condition of debt to criminal gangs for smuggling them into the UK.

The researchers, including a Detective Inspector who completed a Masters at Cambridge's Institute of Criminology, argue that police take too narrow a view of modern slavery when it comes to "growers" arrested during cannabis farm raids.

While growers - often Vietnamese nationals - are not always imprisoned within farms, many work under threat of extreme violence towards themselves or family back home, with little in the way of language or contacts in the UK.

The researchers say that arresting officers often lack detailed training on modern slavery, and make only "perfunctory" enquiries: a brief question that places the onus on a victim who doesn't understand their own situation.

As such, migrants end up serving years in UK prisons despite being forced to commit the cultivation crimes by gangs who seize passports and threaten - and administer - violence.

"The abuses of freedom in cannabis farm cases do not tally with traditional perceptions of slavery. Victims may be held against their will, forced to work and unable to leave, despite an unlocked door," said Prof Heather Strang, the study's senior author.

"Big questions remain about how the criminal justice system should ethically manage modern slavery victims who are also illegal immigrants involved in illegal activity," she said.

The new study, published in the Cambridge Journal of Evidence-Based Policing, was co-authored by DI Adam Ramiz of Surrey Police as part of his research at Cambridge, where he worked with Strang and Prof Paul Rock from LSE.

Cannabis farms are unassuming abodes in towns and city suburbs that house hundreds of plants in blacked-out rooms, grown with equipment such specialist lighting. A live-in "grower" will work for criminal gangs to feed and protect the Class B drug crop.

The latest study is small in scale - gaining access to growers willing to talk is difficult - but criminologists say that it's an important addition to this under-researched area.

The team looked at criminal histories of 19 Vietnamese nationals arrested in connection with cannabis farming in Surrey and Sussex between 2014-2017, and conducted in-depth interviews with three further growers - two Vietnamese and an Albanian - as well as the arresting officers in those cases.

The growers all described being in hock to human smugglers, working in farms to pay debts, and some spoke of death threats and physical intimidation. Two spoke of dangerous journeys to the UK via lorries, similar to the 39 Vietnamese nationals found dead in Essex last year.

One witnessed murder by smugglers while trekking for days through forests. Another was locked inside the house once in the UK. The victims didn't consider themselves such, as they had wanted to come here, yet had been forced into illegal labour on arrival: smuggling that becomes trafficking.

Interviews with officers revealed police questioning on slavery to be limited, cursory and "binary" - whether or not the grower was physically locked in - and conducted with a presumption of guilt on the that the grower is an offender.

"We found that some officers only had an hour of modern slavery training, and felt that the onus is on trafficking victims to volunteer that information, rather than police to investigate further," said Ramiz, who led the study.

"The brief question or two on slavery will often come after a grower has been given the standard legal advice to say nothing and later to plead guilty," he said.

Police frustrations focus on growers, with one officer talking of "hitting a brick wall" if they won't open up, but researchers say that the legal advice offered to trafficked cannabis growers is routine and uncritical: "go quietly".

They argue that police should "re-frame" their response to cannabis farms so that the possibility of modern slavery is "more fully considered", and suggest detailed training for front-line officers along with greater willingness to refer cases to specialist investigators.

Dame Sara Thornton, the UK's Independent Anti-Slavery Commissioner, described the study as a "welcome contribution to building an evidence-based approach to preventing modern slavery".

"The Modern Slavery Act includes a statutory defence for those compelled to commit an offence as a direct result of their being a victim of modern slavery. It is essential that the police investigate all lines of enquiry when they come across these complicated cases," said Thornton.

Added Ramiz: "While much more research is needed, these accounts of debt bondage and fierce intimidation suggests the mass cultivation of cannabis is rife with modern slavery, and the grey area between offender and victim in these cases can become a blind spot for UK police."

Case study:

A 34-year-old Vietnamese man now in an English prison for growing cannabis told researchers he had been a taxi driver, before fleeing his home after taking part in protests against a Chinese oil rig in the disputed South China sea.

Accused of betraying his country by police, he entered into contract with a smuggler after fearing for his life when a friend disappeared following arrest. Unable to pay in full, he ended up in debt bondage to a criminal gang.

Believing he was going to the UK to work in kitchens, the grower found himself in a series of lorries and flights across China and Russia, and taken into Europe via the forests of Poland.

"You have to walk for maybe two, three days... I saw one person had been beaten up... when I turned around he was unconscious... he walked too slow," the grower told researchers. He believed the person he described had died.

The grower arrived in the UK in a lorry container. He was eventually taken to a house already full of cannabis plants and shown how to tend them, and given an allowance for food and phone calls home.

"I do not dare leave the house without telling them, because I fear for my life... They told me if I tried to escape they would harm my family," said the grower.

He remembered police asking some questions about being forced to work, and he had told them. His legal advisor asked no such questions. He did not consider himself a trafficking victim, as he had wanted to come to the UK.

The police interviewer of the grower was a 33-year-old probationary police officer. He had been given an interview plan, and told researchers he viewed the matter in simple terms: "...you're interviewing him as a suspect to get a confession, or to get the points across to get the conviction or charge...".

No trafficking questions were in the officer's plan, but he asked some anyway based on the grower's response. The officer acknowledged his ignorance of modern slavery legislation to researchers.

A further interview was done by the officer's supervisor, who was in charge of the investigation. He told researchers the training given to police on slavery - one hour-long session - was insufficient, and until guidance improved they had to rely on instinct.

The officer-in-charge entered a submission to the National Referral Mechanism - the framework set up in 2009 to ensure victims of trafficking receive help. The NRM returned a decision that the grower had "consented" to the illegal work, so was not a victim, and he was sentence to prison.

Faulty glass in tables can cause life-threatening injuries, according to a Rutgers study, which provides evidence that stricter federal regulations are needed to protect consumers.

The study, published in the American Journal of Surgery, reviewed 3,241 cases in the National Electronic Injury Surveillance System database and 24 cases from a level 1 trauma center. They found most of the injuries occurred in children under age 7 and in young adults in their early 20s.

Injuries that mostly affected the arms, shoulders and forehead, ranged from minor abrasions and damage to major organs and vessels, to death.

Glass table injuries are common, with more than 2.5 million per year reported, many of which are treated in trauma centers and emergency departments.

According to the U.S. Consumer Product Safety Commission, tempered glass is mandatory for doors but voluntary for horizontal surfaces such as tabletops, which often are made with untempered glass and are more likely to break into sharp edges that can cause severe lacerations.

In the national database, 1,792 of the faulty table injuries were lacerations and 24 were blunt injuries resulting from a fall after a table broke. Most frequently injured areas were the wrist, hand and finger. About 15 percent of the injuries were classified as severe, including those to the upper and lower trunk and the wrist.

At the trauma center, half of the patients suffered injuries to their deep organs, upper torso, abdomen or joint cavities and required surgery; eight percent died within a month of injury.

About 70 percent of those injured were male, with most injuries occurring in people under age 7 and in their early twenties.

Injuries occurred when people fell into faulty glass tables, often breaking through, or from glass after the table was broken. People who had non-glass injuries, such as striking against or falling from a glass table, occurred most often in children under age 10, with injuries most often to the face, head and mouth.

"It is imperative to push for stricter regulation as consumers of glass tables should not be incurring life-threatening trauma injuries due to neglect of manufacturers in not using tempered glass," said study author Stephanie Bonne, an assistant professor of surgery at Rutgers New Jersey Medical School.

COVID-19 has left many victims of domestic violence facing difficulties feeding their children and accessing services for safe housing, transportation and childcare once they leave shelters, according to a Rutgers study published in the journal Violence Against Women.

"Many survivors exiting domestic violence shelters are reporting difficulties in accessing resources within the community. Survivors in our study voiced concerns regarding access to food and transportation and securing safe housing, employment and affordable child care," said lead investigator Amanda M. Stylianou, a director at Rutgers University Behavioral Health Care.

The researchers conducted three interviews with some 83 survivors over nine months in six emergency domestic violence shelters providing supportive services to victims of crime and abuse.

Participants reported a lack of choice in both housing options and the communities they could move into, as well as an overall lack of stability and structure in the transition process and beyond. They also identified difficulties in accessing community resources and stressed that additional resources are needed to protect domestic violence victims and their children in the community.

After leaving, many respondents moved into overcrowded apartments, returned to apartment buildings where the abusive partner resided or returned to the abusive relationship after being in need of housing. Parents shared their children's concerns about feeling lonely, missing family and friends and the difficulties they experienced in moving in and out of shelters.

"In our COVID-crisis world, families exiting domestic violence shelters are facing a range of stressors impeding their ability to gain independence and remain free from their abusive partners," said Stylianou. "Finding creative ways to support survivors in accessing financial assistance and/or safe housing are critical opportunities for communities to support survivors."

Curtin University research has developed a new and easier on-site method to immediately and accurately detect and measure levels of PFAS, which are persistent environmental pollutants sometimes found in contaminated lands and waters around the industrialised world.

Professor Damien Arrigan, from the School of Molecular and Life Sciences at Curtin University, explained PFAS (per- and polyfluorinated alkyl substances) are potentially harmful chemical materials that were used for a long time in various commercial and industrial applications, including in firefighting foams, some non-stick cookware, stain and water resistant coatings on carpet and clothing, and various paper and packaging products.

"As a result of their widespread use, many groundwater and soil sites around the world are contaminated with these materials, which are often referred to as 'forever chemicals,' because they don't breakdown or degrade in the natural environment," Professor Arrigan said.

"The only way to prevent them entering the food chain, is to minimise or remove the chemicals from the environment - making early detection a highly desirable part of this removal process."

Typically speaking, to find out if a site or body of water is contaminated with PFAS materials, soil or water samples must be taken from a site and then taken to a laboratory for chemical analysis, a process which may take several days.

The Curtin research, in collaboration with Universidad Nacional de Córdoba, Argentina, sought to improve this process by using on-site chemical sensors which allow an instant contamination test that immediately indicates which water samples should be collected and sent to a lab for a more detailed chemical analysis.

"The chemical sensors we developed use electrodes to push ionised PFAS across an oil-water interface, or 'boundary,' using special glass membranes with microholes. This process changes the electrical properties of the interface and gives us an electrical current that tells us about the concentration of substances," Professor Arrigan said.

"This method allows us to not only detect the presence of perfluorooctane sulfonate, one of the most widely used PFAS, but also measure it at very low concentration levels - lower than the concentration values set for safe limits of this substance in drinking water.

"Our preliminary results show that with our new method, it is possible to immediately detect very small concentrations of PFAS substances in waters, without the need to send the samples offsite for initial analysis.

"With appropriate development into a more portable, robust technology, this method could potentially be used by industry and government agencies, and the general public, to monitor PFAS concentration in water and soils and get results within minutes, rather than days."

The full research paper, Detection of perfluorooctane sulfonate by ion-transfer stripping voltammetry at an array of microinterfaces between two immiscible electrolyte solutions, was published in the journal Analyst and can be found online here.

Animals in tropical and Mediterranean areas are the most sensitive to climate change and land use pressures, finds a new study by UCL researchers.

The findings, published today in Nature Ecology & Evolution, show how extinction risks are not evenly distributed worldwide, and suggest that large declines in tropical biodiversity are likely to occur imminently.

Lead author Dr Tim Newbold (UCL Centre for Biodiversity & Environment Research) said: "Tropical areas are expected to see the greatest expansions of agriculture in the coming decades, and are already seeing new temperature extremes.

"Coupled with the fact that data on biodiversity are often biased towards more temperate regions, our findings suggest that global biodiversity declines may be even worse than leading experts are predicting. Urgent action is needed to prevent biodiversity losses and extinctions, particularly in tropical and Mediterranean areas which have some of the most diverse ecological communities on the planet."

The research team analysed data on 47,044 species of animals, plants and fungi at thousands of sites in 91 countries to measure the number of different species living in more disturbed environments such as cities and intensive agricultural areas, or in moderately disturbed or wild spaces. The team also compared data on where species are able to survive against regional climate modelling data to predict responses to climate change.

The researchers found substantially lower biodiversity in more disturbed environments, especially in Mediterranean and tropical regions. They also found that among vertebrates, those most sensitive to climate warming are found in tropical forests, tropical grasslands and Mediterranean areas. Species of concern include the eastern gorilla, critically endangered due to habitat loss and climate change in the African tropics, and Hermann's tortoise, a Mediterranean animal currently threatened by habitat loss and likely climate change as well in years to come.

Across species in tropical regions, the researchers projected local declines of 10 to 13% in the number of species for each degree of climate warming.

Species in areas with less pronounced seasonal changes, particularly in the tropics, were found to be the most vulnerable to climate change. The researchers note that plants and animals that have not adapted to wide ranges of temperatures across seasons are more likely to suffer if temperatures rise. In tropical and Mediterranean regions, many species were found to be already living near the upper temperature limit that they can tolerate.

One partial explanation for the findings is that some other biomes (communities of plants and animals occupying a particular habitat) have been heavily influenced by humans for centuries, indicating that the most sensitive species are likely to have already been wiped out.

While not tested in the study, the researchers say that tropical species may also be more vulnerable due to smaller range sizes and high concentrations of specialist species, as well as those that mature more slowly and produce fewer offspring.

Dr Newbold said: "We found that areas facing the greatest biodiversity threats from climate change and land use were often the same areas, which is even more concerning as these two pressures can interact to make environments even more inhospitable. For example, heavily modified landscapes often have less canopy cover which would otherwise moderate extreme temperatures."

Dr Newbold is also a co-author of the World Wildlife Fund's Living Planet Report, published this month, which showed that biodiversity has declined most in the tropics since 1970. He and colleagues argue that coordinated global efforts are needed to turn the tide of biodiversity loss.

"Conservation efforts alone will not be enough to save endangered and vulnerable animals and plants. Governments, private companies and consumers will all need to act now to curb climate change and to mitigate land use pressures that destroy habitats," he said.

HOUSTON and SAN FRANCISCO ? New preclinical research from The University of Texas MD Anderson Cancer Center and BridgeBio Pharma, Inc. affiliate Navire Pharma, Inc., finds that the novel SHP2 inhibitor IACS-13909 is able to overcome multiple therapeutic-resistance mechanisms in non-small cell lung cancer (NSCLC), suggesting a possible new approach to treating cancers that have developed resistance to the targeted EGFR inhibitor osimertinib.

The data is published today in Cancer Research, a journal of the American Association for Cancer Research. IACS-13909, is a potent and selective allosteric SHP2 (Src homology 2 domain-containing phosphatase) inhibitor developed through collaboration between Navire and MD Anderson's Therapeutics Discovery division. Based on these data, Navire plans to launch a clinical study of SHP2 inhibitors by the end of 2020 at multiple US sites, including MD Anderson.

IACS-13909 was initially discovered as an SHP2 inhibitor by a team of scientists in MD Anderson's Institute for Applied Cancer Science (IACS) and Translational Research to Advance Therapeutics and Innovation in Oncology (TRACTION) platforms, both engines within the Therapeutics Discovery division.

"Tyrosine kinase inhibitors, like osimertinib, appear initially effective in suppressing tumor growth, but multiple mechanisms of resistance can develop while a patient is still receiving treatment," said Nancy Kohl, Ph.D., a senior author of the study and member of Navire's scientific advisory board. "This study shows that IACS-13909's ability to inhibit a protein downstream of multiple signaling pathways is a promising approach in overcoming these common tumor-resistance mechanisms."

Osimertinib is a targeted EGFR inhibitor used as a front-line option for treating patients with NSCLC harboring specific EGFR mutations. However, NSLCs frequently develop osimertinib resistance over time, either through additional mutations in EGFR that block activity of the drug, or by activating compensatory signaling pathways.

SHP2 is a protein that acts downstream in these pathways, and it is required for full activation of the MAPK signaling pathways, which is known to fuel tumor growth, proliferation and survival.

"Our findings show that IACS-13909 is capable of suppressing tumor cell proliferation in vitro and causing tumor regression in vivo for lung cancers harboring a variety of activated kinases as the oncogenic driver," said lead author Yuting Sun, Ph.D., co-project lead and senior research scientist with TRACTION at MD Anderson. "These data suggest that targeting SHP2 could provide a viable strategy for overcoming osimertinib resistance occurring through a variety of mechanisms."

These results were consistent when IACS-13909 was used as a single agent and in combination with osimertinib in vivo. The combination treatment in vitro led to prolonged, more durable responses in tumors that were sensitive to osimertinib and stimulated tumor regression in osimertinib-resistant models.

"Through our collaboration with the Therapeutics Discovery team at MD Anderson, we continue to uncover SHP2's critical role in activating multiple different pathways related to cancer's onset and growth," said Eli Wallace, chief scientific officer of oncology at BridgeBio, Navire's parent company. "This study further supports the very reason that Navire was founded - to develop novel SHP2 insights into targeted medicines for patients in need. We look forward to advancing our lead SHP2 inhibitor into the clinic later this year."

HANOVER, N.H. - September 14, 2020 - Information on social activity, screen time and location from smartphones can predict connectivity between regions of the brain that are responsible for emotion, according to a study from Dartmouth College.

In the research, data from phone usage was analyzed alongside results from fMRI scans to confirm that passively collected information can mirror activity in the brain linked to traits such as anxiety. Predictions based solely on the phone data matched the brain scans with 80 percent accuracy.

The study, presented at ACM UbiComp, an annual conference on pervasive and ubiquitous computing, represents the first time researchers have been able to predict connectivity between specific brain regions solely based on passive data from smartphones.

"Simple information about how someone is using their smartphone can provide a peek into the complex functioning of the human brain," said Mikio Obuchi, a PhD student in the Department of Computer Science at Dartmouth and lead author of the study. "Although this research is just beginning, combining data from smartphones--rather than fMRI alone--will hopefully accelerate research to understand better how the human brain works."

According to the research, how often and how long an individual uses their phone provides information about the functioning between the ventromedial prefrontal cortex and the amygdala--two key centers of the brain related to emotional state.

The ventromedial prefrontal cortex is responsible for self-control, decision making, and risk evaluation. The amygdala triggers the "fight or flight" response and helps individuals determine the emotions of others.

In addition to data on social activity, screen time and location, information on exercise and sleep patterns was also collected for the study.

The research found that more screen time, regular exercise, earlier bedtimes, higher social interaction and certain location patterns passively inferred from phone data matched a state of higher functional connectivity between the brain regions. This increased activity indicates a more positive emotional state.

"We are not suggesting that phones should replace technology like fMRI, but they can help individuals and health providers learn more about behavior patterns from everyday observations," said Jeremy Huckins, a lecturer on psychological and brain sciences at Dartmouth and a co-author of the study.

The research result aligns with clinical evidence showing that stronger connectivity between the ventromedial prefrontal cortex and the amygdala to be associated with lower levels of anxiety and depression. Weaker functional connectivity, on the other hand, represents a more negative emotional state.

Anonymous fMRI data from volunteer participants were placed into two categories divided by low and high brain connectivity levels. By matching phone data against the fMRI results the researchers were able to predict which research subjects had higher or lower connectivity between brain regions with 80 percent accuracy.

According to the research team, the use of passive information from a smartphone can help eliminate the subjectivity that often complicates other information-gathering techniques on emotional well-being such as personal interviews and self-reporting on questionnaires.

The phone information allowed researchers to predict the emotional state of individuals at any given time without intrusive data collection. The data also support predictions of the long-term emotional traits in individuals.

"Hopefully, this study shows how mobile sensing can provide deep longitudinal human behavioral data to complement brain scans," said Andrew Campbell, the Albert Bradley 1915 Third Century Professor of computer science at Dartmouth and the senior researcher on the study. "This could offer new insights into the emotional well-being of subjects that would just not be possible without continuous sensing."

The research, published in the Proceedings of the ACM on Interactive, Mobile, Wearable and Ubiquitous Technologies, is part of Dartmouth's Student Life study that monitors telephone data from student volunteers to determine mental well-being. Over 100 first-year students participated in the year-long study on passive sensing and brain function.

Organisations could improve the transparency and accountability of COVID-19 policy making processes by learning from safety-critical industries like aviation, a new paper shows.

The research, from the University of York, examines the modelling assumptions that have been informing the COVID-19 policy-making processes and to what extent these assumptions and their limitations are communicated to decision-makers.

Dr Ibrahim Habli, from the Assuring Autonomy International Programme in the Department of Computer Science, said: "When making claims about risk in safety-critical systems, such as in the aviation industry, it is common practice to produce an assurance case. This is a structured argument, supported by evidence, which aims to assess how confident we should be in the decisions we make based on simulation results.

"We acknowledge the need for these simulation models to help us deal with the pandemic. We argue that any model that is used to guide critical policy decisions would benefit from being supported with such an assurance case to explain how, and to what extent, the evidence from the simulation can be relied on to substantiate policy conclusions. This would enable a critical review of the implicit assumptions and inherent uncertainty in modelling, and would give the overall decision-making process greater transparency and accountability."

The paper also suggests multidisciplinary teams - made up of experts with different expertise - are needed to develop the models and their assurance cases. Dr Ibrahim Habli added: "If such multidisciplinary teams, including clinicians, data scientists and others, were to work together to develop, test and assure the models used we would have transparency of the data and results generated, and policymakers would be able to better assess the quality and value of this evidence."

An international team of doctors have developed a machine learning system which can predict the development of Bipolar Disorder up to 4 years before onset in young people: at age 18 it was able to predict which individuals would develop the condition at age 22. This work is presented at the ECNP virtual congress, and is in press with a peer-reviewed journal*(See below).

"This may be a new additional tool for the diagnosis of bipolar disorder; this will not replace a doctor's diagnosis, but may allow them to take preventative measures to slow or avoid the onset of the condition, and so gain 4 years of preventative treatment" said lead researcher Francisco Diego Rabelo-da-Ponte.

The researchers, from Brazil, Canada and the USA, followed 3810 individuals born in Pelotas, Brazil, in 1993, taking measurements and interviews at the ages of 11, 15, 18 and 22. The study was looking at general health from birth, but has had a particular application in mental health. At the end of the 22 year follow up, 255 of the people in the study (6.7%) had received a diagnosis of bipolar disorder.

Lead researcher Francisco Diego Rabelo-da-Ponte, from the Federal University of Rio Grande do Sul, Brazil said:

"What we found was that we can identify who will develop bipolar disorder around four years before the onset of the condition, by tracking the individuals from birth through to adulthood. We used machine learning techniques which are based on the same learning techniques used to detect such things as spam and weather forecasting.

There were several factors which tended to point to a greater risk for bipolar disorder, For example if 18 year olds show more suicidal tendency, general anxiety, evidence of parental physical abuse, and financial problems, then they may have been at greater risk. It was the job of the machine learning to weigh these factors and estimate the risk of developing bipolar disorder".

Bipolar disorder is estimated to be the sixth cause of disability in the world, however, its proper identification still frequently represents a challenge, with an average delay of six years between first symptoms and formal diagnosis. Additionally, only 20% of people with bipolar disorder and presenting with a depressive episode are diagnosed with bipolar disorder within the first year of seeking treatment. Diagnostic and treatment delays have harmful consequences for the clinical course of illness, for example, greater severity of symptoms, shorter time between episodes of mood, cognitive and functional impairment. Identifying bipolar disorder early is a growing interest because many patients are mistreated and misdiagnosed, avoiding the progression of the disease.

Francisco Diego Rabelo-da-Ponte said:

"It's very difficult and expensive to replicate such a long-lasting study, but what we have found indicates that we need more of these longitudinal studies. We've already learned a lot from the study itself, for example if we were to set it up now we would include many more mental health parameters, which we hope would allow us to identify even more psychological benefits. We see too many false positives (indicating someone is at risk when they are not) to rely 100%% on this system alone. Nevertheless, this system will allow doctors to see who might be at risk, and the gain of 4 years before diagnosis could make a huge difference to the life of a young person".

Commenting, Professor Eduard Vieta (Barcelona), ex-ECNP Executive Committee member said:

"Population-based cohort studies are extremely important to develop predictive models that may aid in the prevention of serious conditions such as bipolar disorder. There have been other initiatives in the past to build calculators with that aim. What is most needed is replication and verification of the validity of the algorithm. The present study, hence, has its merits but is relatively small and needs replication in a separate, independent cohort; moreover, unusual findings such as the underrepresentation of bipolar II disorder need clarification as well."

This is an independent comment; Professor Vieta was not involved in this work.

Appointing a new leader just before an election leads to a higher turnover of MPs after the poll, a study of political parties across Europe during the past 80 years shows.

A change at the top is a key determinant of how many politicians will step down and be re-elected, experts who have analysed hundreds of electoral contests since 1945 have found.

The proportion of new and re-elected MPs is almost 5 percentage points higher on average for parties which changed their leadership before an election compared to those that did not do so.

Athanassios Gouglas and Gabriel Katz from the University of Exeter, and Bart Maddens and Marleen Brans from KU Leuven Belgium, analysed statistics from 251 parties in Europe between 1945 and 2015. They looked at the impact of changes in parties' leadership and name, the formation of electoral cartels, mergers and divisions on the turnover rates of politicians in Austria, Belgium, France, Italy, the Netherlands, Sweden, Switzerland and the UK.

Dr Gouglas said: "Our analysis provides support for the notion of an "iron law of leadership", where new leaders have ample influence on their parties' legislative delegations. The arrival of a new leader is consistently followed by an influx of newcomers in parliament, regardless of the influence that other factors--like electoral performance--may exert on legislative turnover.

"The statistics show new leaders have always been important, at least when it comes to the control of parties' parliamentary delegations."

The researchers found the impact of having a new leader has been similar since 1945 - a change in the turnover of MPs after a new leader has been 4.5 per cent over the past 30 years and 4.3 per cent for before 1989.

The study also shows divisions in political parties, and attempts to relabel them, also affect the turnover of MPs.

The research shows following a split in a party the main successor parties witness an influx of new and re-entering MPs, while renewal rates of parliamentarians declines among the splinter groups emerging from the division. The rate of legislative turnover is 3.66 percentage points higher for parties which changed name before an election compared to those which did not attempt such rebranding.

Allowing for other influences on the turnover of politicians the proportion of new and re-entering MPs following a party split is about five percentage points higher for the main successor party and five points lower for parties that did not break up.

Researchers measured politician turnover by measuring the number of new and returning MPs relative to the number of legislative seats captured by a party in a given election. Data was collected about 18,151 MPs and 155 general elections from parliamentary registries and MP biographical profiles. The average rate of party legislative turnover following an election was 37.30 per cent.

Changes to the name of a party only had an influence on politician turnover in parties with a strong enough position to be able to shape policy. This suggests that parties with little policy-making clout do not have sufficient "brand equity" for a name change to attract new--successful--candidates and substantially alter the composition of their legislative delegation. Instead, relabelling seems to be barely enough to allow such parties to survive and their incumbents to be re-elected into office.

Tropical Depression Rene continues to be the victim of strong wind shear and forecasters anticipate it will lead to the storm's demise in the next couple of days. NASA's Aqua satellite viewed the storm in infrared light to find wind shear was pushing Rene's strongest storms away from the center, preventing the storm from re-organizing and strengthening.

NASA's Aqua Satellite Reveals Effects of Wind Shear 

On instrument aboard NASA's Aqua satellite uses infrared light to analyze cloud top temperatures in a tropical cyclone's clouds to determine strength. The strongest thunderstorms that reach high into the atmosphere have the coldest cloud top temperatures.

On Sept. 15 at 1:05 a.m. EDT (0505 UTC), the Moderate Resolution Imaging Spectroradiometer or MODIS instrument that flies aboard NASA's Aqua satellite gathered infrared data on Rene that confirmed wind shear was adversely affecting the storm. Persistent north-northeasterly vertical wind shear showed strongest storms (red) pushed to the east-southeast of the center where cloud top temperatures were as cold as minus 70 degrees Fahrenheit (minus 56.6 Celsius).

National Hurricane Center forecaster Jack Beven noted, "Rene continues to produce just enough deep convection to keep it from degenerating to a remnant low.  However, it is expected to degenerate later today due to the ongoing impact of strong west-northwesterly vertical shear and dry air entrainment."

Wind Shear Affecting Rene

The shape of a tropical cyclone provides forecasters with an idea of its organization and strength. When outside winds batter a storm, it can change the storm's shape and push much of the associated clouds and rain to one side of it. That is what wind shear does.

In general, wind shear is a measure of how the speed and direction of winds change with altitude. Tropical cyclones are like rotating cylinders of winds. Each level needs to be stacked on top each other vertically in order for the storm to maintain strength or intensify. Wind shear occurs when winds at different levels of the atmosphere push against the rotating cylinder of winds, weakening the rotation by pushing it apart at different levels.

Status of Tropical Depression Rene  

At 5 a.m. EDT (0900 UTC), the center of Tropical Depression Rene was located near latitude 27.4 degrees north and longitude 48.3 degrees west. Rene is centered about 1,115 miles (1,795 km) northeast of the Leeward Islands. The depression is moving toward the west near 3 mph (6 km/h). Maximum sustained winds are near 30 mph (45 kph) with higher gusts. The estimated minimum central pressure is 1011 millibars.

Rene's Forecast

A faster motion toward the west-southwest or southwest is forecast to begin later today, Sept. 14 and continue through dissipation. Weakening is forecast, and Rene is expected to become a remnant low later today and dissipate by Wednesday, Sept. 16.

NASA Researches Tropical Cyclones

Hurricanes/tropical cyclones are the most powerful weather events on Earth. NASA's expertise in space and scientific exploration contributes to essential services provided to the American people by other federal agencies, such as hurricane weather forecasting.

For more than five decades, NASA has used the vantage point of space to understand and explore our home planet, improve lives and safeguard our future. NASA brings together technology, science, and unique global Earth observations to provide societal benefits and strengthen our nation. Advancing knowledge of our home planet contributes directly to America's leadership in space and scientific exploration.

For updated forecasts. visit: http://www.nhc.noaa.gov