Culture

If you think that the Sahara is covered only by golden dunes and scorched rocks, you aren't alone. Perhaps it's time to shelve that notion. In an area of West Africa 30 times larger than Denmark, an international team, led by University of Copenhagen and NASA researchers, has counted over 1.8 billion trees and shrubs. The 1.3 million km2 area covers the western-most portion of the Sahara Desert, the Sahel and what are known as sub-humid zones of West Africa.

"We were very surprised to see that quite a few trees actually grow in the Sahara Desert, because up until now, most people thought that virtually none existed. We counted hundreds of millions of trees in the desert alone. Doing so wouldn't have been possible without this technology. Indeed, I think it marks the beginning of a new scientific era," asserts Assistant Professor Martin Brandt of the University of Copenhagen's Department of Geosciences and Natural Resource Management, lead author of the study's scientific article, now published in Nature.

The work was achieved through a combination of detailed satellite imagery provided by NASA, and deep learning -- an advanced artificial intelligence method. Normal satellite imagery is unable to identify individual trees, they remain literally invisible. Moreover, a limited interest in counting trees outside of forested areas led to the prevailing view that there were almost no trees in this particular region. This is the first time that trees across a large dryland region have been counted.

The role of trees in the global carbon budget

New knowledge about trees in dryland areas like this is important for several reasons, according to Martin Brandt. For example, they represent an unknown factor when it comes to the global carbon budget:

"Trees outside of forested areas are usually not included in climate models, and we know very little about their carbon stocks. They are basically a white spot on maps and an unknown component in the global carbon cycle," explains Martin Brandt.

Furthermore, the new study can contribute to better understanding the importance of trees for biodiversity and ecosystems and for the people living in these areas. In particular, enhanced knowledge about trees is also important for developing programmes that promote agroforestry, which plays a major environmental and socio-economic role in arid regions.

"Thus, we are also interested in using satellites to determine tree species, as tree types are significant in relation to their value to local populations who use wood resources as part of their livelihoods. Trees and their fruit are consumed by both livestock and humans, and when preserved in the fields, trees have a positive effect on crop yields because they improve the balance of water and nutrients," explains Professor Rasmus Fensholt of the Department of Geosciences and Natural Resource Management.

Technology with a high potential

The research was conducted in collaboration with the University of Copenhagen's Department of Computer Science, where researchers developed the deep learning algorithm that made the counting of trees over such a large area possible.

The researchers show the deep learning model what a tree looks like: They do so by feeding it thousands of images of various trees. Based upon the recognition of tree shapes, the model can then automatically identify and map trees over large areas and thousands of images. The model needs only hours what would take thousands of humans several years to achieve.

"This technology has enormous potential when it comes to documenting changes on a global scale and ultimately, in contributing towards global climate goals. We are motivated to develop this type of beneficial artificial intelligence," says professor and co-author Christian Igel of the Department of Computer Science.

The next step is to expand the count to a much larger area in Africa. And in the longer term, the aim is to create a global database of all trees growing outside forest areas.

Wear a mask, keep your distance, avoid crowds - these are the common recommendations to contain the COVID-19 epidemic. However, the scientific foundations on which these recommendations are based are decades old and no longer reflect the current state of knowledge. To change this, several research groups from the field of fluid dynamics have now joined forces and developed a new, improved model of the propagation of infectious droplets. It has been shown that it makes sense to wear masks and maintain distances, but that this should not lull you into a false sense of security. Even with a mask, infectious droplets can be transmitted over several meters and remain in the air longer than previously thought.

TU Wien (Vienna), the University of Florida, the Sorbonne in Paris, Clarkson University (USA) and the MIT in Boston were involved in the research project. The new fluid dynamics model for infectious droplets was published in the "International Journal of Multiphase Flow".

A new look on old data

"Our understanding of droplet propagation that has been accepted worldwide is based on measurements from the 1930s and 1940s", says Prof. Alfredo Soldati from the Institute of Fluid Mechanics and Heat Transfer at TU Wien. "At that time, the measuring methods were not as good as today, we suspect that especially small droplets could not be measured reliably at that time".

In previous models, a strict distinction was made between large and small droplets: The large droplets are pulled downwards by gravity, the small ones move forward almost in a straight line, but evaporate very quickly. "This picture is oversimplified," says Alfredo Soldati. "Therefore, it is time to adapt the models to the latest research in order to better understand the propagation of COVID-19".

From a fluid mechanics point of view, the situation is complicated - after all, we are dealing with a so-called multiphase flow: The particles themselves are liquid, but they move in a gas. It is precisely such multiphase phenomena that are Soldati's specialty: "Small droplets were previously considered harmless, but this is clearly wrong," explains Soldati. "Even when the water droplet has evaporated, an aerosol particle remains, which can contain the virus. This allows viruses to spread over distances of several meters and remain airborne for long time."

In typical everyday situations, a particle with a diameter of 10 micrometers (the average size of emitted saliva droplets) takes almost 15 minutes to fall to the ground. So it is possible to come into contact with virus even when distancing rules are observed - for example in an elevator that was used by infected people shortly before. Particularly problematic are environments with high relative humidity, such as poorly ventilated meeting rooms. Special care is required in winter because the relative humidity is higher than in summer.

Protection rules: Useful, but not enough

"Masks are useful because they stop large droplets. And keeping a distance is useful as well. But our results show that neither of these measures can provide guaranteed protection," says Soldati. With the mathematical model that has now been presented, and the current simulations under way it is possible to calculate the concentration of virus-carrying droplets at different distances at different times. "Until now, political decisions on COVID-protection measures have mainly been based on studies from the fields of virology and epidemiology. We hope that in the future, findings from fluid mechanics will also be included," says Alfredo Soldati.

"For 30 weeks already, our study has been documenting how people assess what is happening around the coronavirus," says BfR President Professor Dr. Dr. Andreas Hensel. "This enables us to observe how people react to changes in the pandemic."

https://www.bfr.bund.de/cm/349/201013-bfr-corona-monitor-en.pdf

Further trends in the overview:

Classification of possible sources of infection

Since March, the survey has registered which sources the respondents consider as possible transmission pathways for the coronavirus. Over the entire course of the survey, a stable pattern has been observed: Proximity to other people is mostly associated with a high probability of infection (67 percent in the current survey). Relatively often, contact with door handles is also seen as a source of infection (44 percent). In contrast, the probability of transmission through food, pets or clothing is usually rated as low.

Personal protective measures

The regulations - including the mandatory use of masks and the mandatory distance - are continuously implemented by the vast majority. More attention is also paid to hygiene: In the current survey, respondents said that they protect themselves against an infection by washing their hands more thoroughly (92 percent) and using disinfectants more frequently (74 percent). Many also restrict their social contacts. However, a downward trend could be observed over the summer: While in June about 80 percent said that they met with others less often, this figure has dropped to 60 percent in recent months.

Information behaviour

Since the beginning of the epidemic in Germany, people have informed themselves through various information channels: Here, traditional media such as radio, print and particularly television play a role, as do conversations among acquaintances or the Internet. In this respect, the majority of respondents consider the media coverage surrounding the outbreak to be appropriate (65 percent in the current survey), while around a third (30 percent) rate it as exaggerated.

What happens next?

The BfR-Corona-Monitor will continue in November. The survey will continue to be carried out every two weeks and will comprise around 1,000 people at a time.

The BfR continually adapts its FAQs on the topic of coronavirus to the current state of science:

https://www.bfr.bund.de/en/can_the_new_type_of_coronavirus_be_transmitted_via_food_and_objects_-244090.html

Washington, October 20, 2020--A study of 33 public community college promise programs, or free-college programs, across the United States found that they are associated with large enrollment increases of first-time, full-time students--with the biggest boost in enrollment among Black, Hispanic, and female students. The results come as the economic impact of the Covid-19 pandemic is leading states to tighten higher education budgets, as low-income students are forgoing their postsecondary plans at higher rates this fall than their wealthier peers, and as community colleges are experiencing larger enrollment declines than four-year universities. The study was published today in Educational Evaluation and Policy Analysis, a peer-reviewed journal of the American Educational Research Association.

The research, conducted by Denisa Gándara at Southern Methodist University and Amy Li at Florida International University, is the first on this topic to examine the effects of multiple promise programs on enrollment at community colleges across the United States. For their study, the authors analyzed data from the U.S. Department of Education's Integrated Postsecondary Education Data System, for academic years 2000-01 to 2014-15, to examine the impact of 33 promise programs at 32 community colleges.

Gándara and Li found that, on average, overall enrollments at the community colleges with promise programs increased 23 percent more than at the seven geographically nearest public community colleges without promise programs. Compared to the nearest seven community colleges, promise colleges experienced a 47 percent greater enrollment increase of Black males, a 51 percent greater enrollment of Black females, a 40 percent greater enrollment of Hispanic males, and a 52 percent greater enrollment of Hispanic females. (These increases occurred at different times, depending on when each college had a promise program between 2000 and 2015.) The only groups that did not, on average, experience an enrollment boost associated with promise programs were Asian, Native Hawaiian, and Pacific Islander (API) males and females.

"Prior to the pandemic, promise programs were an increasingly popular mechanism for enhancing college entry and postsecondary attainment," said Gándara, an assistant professor of education policy and leadership at Southern Methodist University. "Our study offers compelling evidence, and reinforces evidence from prior research, of the benefits of such programs in achieving college enrollment goals."

"Our overall findings also offer encouraging evidence that promise programs can help more historically underserved students enroll in college," said Gándara.

In addition, Gándara and Li noted that the effects on enrollment for different demographic groups differed based on program design features and eligibility criteria. These included whether the programs were merit-based or need-based, whether they paid partial or full tuition, and whether the amount of the financial support provided was determined before ("first dollar in") or after ("last dollar in") students' other sources of aid were considered.

Programs with merit-based requirements yielded higher enrollments of White males and females as well as API females, compared to programs without merit-based requirements. Programs with need-based criteria were associated with smaller enrollment increases among all demographic groups, compared to programs without need-based criteria, with the exception of Black males, who showed no difference in effects.

Programs that were "first dollar in" had a significant positive effect on the enrollment of White students but not on other demographic groups. Programs that covered full tuition, as opposed to partial tuition, had a significant positive effect on the enrollment of API students.

"These findings suggest that programs that are more generous might be more likely to attract students categorized as White or API," said Li, an assistant professor of educational policy studies at Florida International University.

"Programs with income criteria have consistent negative effects on enrollment of all groups, except for Black male students," Gándara added. "This could be related to the higher administrative burdens for students, such as requiring proof of income. This potential burden for students should be weighed against the benefits of targeting promise aid to students who need it most."

Findings from the study also reinforced prior research that found promise programs had a greater effect on enrollment than reductions in tuition and fees.

"In addition to reducing price obstacles, promise programs can foster the college-going culture in schools and communities, and change students' perceptions of affordability," Gándara said. "The universal 'free college' and 'college for all' messages that generally accompany promise programs can be especially impactful for racial minority students, who are often subject to lower educational expectations from teachers and counselors and who are more likely to perceive college as unaffordable."

"The budget pressures facing states are very real, as is the developing crisis in college enrollment among the country's least advantaged students," said Li. "Given such encouraging evidence of the effectiveness of community college promise programs on initial college enrollment, working to protect them should be among the top priorities of policymakers."

In birds and other species alike, pairs can face considerable difficulties with reproduction. Scientists at the Max Planck Institute for Ornithology in Seewiesen have now shown in an extensive analysis of 23,000 zebra finch eggs that infertility is mainly due to males, while high embryo mortality is more a problem of the females. Inbreeding, age of the parents and conditions experienced when growing up had surprisingly little influence on reproductive failures.

Zebra finches are small songbirds that originate from Australia. As colony-living granivores, they are easy to keep in aviaries, and they reproduce all year round under favourable conditions. However, reproduction is remarkably unsuccessful: a quarter of the eggs remain unfertilised, and in another quarter of the eggs the embryo dies early during development. Researchers at the Max Planck Institute for Ornithology in Seewiesen have therefore carried out a study to investigate the potential causes of unsuccessful reproduction.

The scientists tracked the fate of more than 23,000 eggs. They measured longevity, productivity, infertility, offspring mortality and other fitness-related traits that covered most phases of reproduction for both sexes. Factors that were expected to influence reproductive failure, such as inbreeding, age of the parents and growing up under unfavourable conditions had negligible effects on the reproductive performance of the zebra finches. This suggests that individuals are remarkably robust to bad conditions and that the causes must lie elsewhere.

When partners are swapped to form new pairs, it becomes clear that problems with fertility typically remain with the male, while problems with embryo mortality typically remain with the female. "Of course, for both problems the pair combination also plays a role", says Yifan Pei, a doctoral student at Seewiesen, "because the formation of a viable embryo requires genes from both the mother and the father".

Although the specific causes of infertility and embryo mortality could not be identified, the researchers showed that reproductive failure has a measurable genetic basis. These results are somewhat surprising, because natural selection should favour genetic variants that optimise reproduction. However, some gene variants that are advantageous for one sex may be disadvantageous for the other. Indeed, the results also indicate that gene variants that reduce male fertility tend to have positive effects on female reproductive output - and vice versa. This effect is known by the technical term "sexually antagonistic pleiotropy" and might explain why such genetic variants can persist in the population.

Many genes influence the reproductive success of zebra finches. Despite the development of sophisticated genomic techniques, it remains difficult to identify and study all genetic components - not to mention the interaction between those genes and the interaction between the genes and the environment in which they are expressed. "If nothing else, the results of the study have shown us where it is not worth looking," says Bart Kempenaers, director of the Department. "Seemingly obvious genetic causes for unsuccessful reproduction, such as inbreeding, contribute far less than we initially thought".

Wolfgang Forstmeier, who supervised the study, adds: "Now we are concentrating our work on a somewhat mysterious chromosome that only exists in the germline (cells that form the egg and the sperm), but not in the body cells of birds. Because it is difficult to take samples from the reproductive organs of living animals, the investigation of the causes is complicated. But the chromosome is a hot candidate for the origin of the problems."

Lack of sleep significantly impairs our ability to stop unwanted and unpleasant thoughts from entering our mind, a new study reveals.

The authors of the study say the findings could have implications for people suffering from psychiatric conditions associated with unwanted thoughts - such as post-traumatic stress disorder, depression and schizophrenia.

The study, from the University of York, tested the ability of participants to suppress intrusive thoughts when they were either sleep deprived or well rested. Sleep deprived participants suffered an increase in unwanted thoughts of nearly 50% compared to those who had a good night's sleep.

Lead author of the study, Dr Marcus Harrington, from the Department of Psychology at the University of York, said: "In everyday life, mundane encounters can remind us of unpleasant experiences. For example, a car driving too fast on the motorway might cause us to retrieve unwanted memories from a car accident many years ago. For most people, thought intrusions pass quickly, but for those suffering with psychiatric conditions such as post-traumatic stress disorder, they can be repetitive, uncontrollable, and distressing.

"It is clear that the ability to suppress unwanted thoughts varies dramatically between individuals, but until now the factors that drive this variability have been mysterious. Our study suggests sleep loss has a considerable impact on our ability to keep unwanted thoughts out of our minds."

For the study, sixty healthy participants learnt to associate faces with photographs of emotionally negative scenes (such as an image from a war zone) or neutral scenes (such as an image of a cityscape).

The following morning, after a night of either sleep or total sleep deprivation, participants were shown the faces and asked to try to suppress thoughts related to the scenes with which they were paired.

Compared to the sleep group, the sleep deprived participants had much more difficulty keeping unwanted thoughts of the emotionally negative and neutral scenes from their minds. While the task became easier with practice for the rested participants, for those who had gone without sleep, thought intrusions remained consistently high.

The sleep group's success at suppressing unwanted thoughts caused them to view the negative scenes more positively after the suppression task, and they also showed a reduced sweat response when the negative scenes were presented. In contrast, the sleep deprivation group's failure to keep unwanted thoughts out of mind meant that they did not experience this positive change in their responses.

Senior author of the study, Dr Scott Cairney, from the Department of Psychology at the University of York, added: "This study offers an important insight into the impact of sleep on mental health. Besides post-traumatic stress disorder and depression, our findings might have implications for our understanding of other disorders linked to sleep disturbances, such as obsessive-compulsive disorder and schizophrenia".

"The study also suggests that the onset of intrusive thoughts and emotional disturbances following bouts of poor sleep could create a vicious cycle, whereby upsetting intrusions and emotional distress exacerbate sleep problems, inhibiting the sleep needed to support recovery".

NUST MISIS material scientists have presented antibacterial nano-coatings based on boron nitride, which are highly effective against microbial pathogens (up to 99.99%). They can become a safe alternative to the usual antibiotics in implantology since they do not have typical negative side effects. The results of the work are published in the international scientific journal ACS Applied Materials & Interfaces.

Nowadays, due to the significant increase in the number of surgical procedures around the world, scientists are solving the problem of microbial infections caused by implants. It is especially serious during orthopedic and dental operations. It is no secret that concomitant drug therapy for inflammation around implants often leads to side effects due to the characteristic properties of the antibiotics, as well as its high doses.

A group of young scientists from NUST MISIS has proposed a non-standard solution to the problem by investigating the interaction of antibiotic-resistant gram-negative bacteria Escherichia coli (E.coli) and a nanofilm consisting of a structured boron nitride surface. It turned out that such a coating inactivates 100% of bacterial cells after 24 hours.

"Hexagonal boron nitride has a complex of unique physicochemical and mechanical properties. As a result of the experiments, we have found out that the special specific structure of boron nitride nanoparticles provides a bactericidal effect comparable to that of an antibiotic: bacteria die as a result of direct physical contact with a special needle-shaped surface of the nano-film. At the same time, there are no side effects typical of an antibiotic on the tissues of the body, and boron nitride itself does not cause cytotoxicity," said Christina Gudz, co-author of the study, a researcher at the NUST MISIS Inorganic Nanomaterials Laboratory.

The researchers went further and filled the micro-pores of a thin coating of boron nitride with the gentamicin antibiotic. The result is an antibacterial effect due to the complete release of the drug in a short initial period. Moreover, its dose was an order of magnitude less than with a conventional injection.

"Taking into account an average patient weight of 60 kg, his daily antibiotic dose is approximately 180 mg; provided that the implant area is, say, 30 cm2 and given that 55 μg of antibiotic is released from the nano-coating under study on the first day, it turns out that the proposed method assumes 100 times less antibiotic than with a standard injection," added Christina Gudz.

According to the authors of the development, the application of an antibacterial film based on boron nitride nanoparticles to the implant can minimize the risk of bacterial contamination due to the physical properties of the surface itself, as well as, in the case of antibiotic modification, local delivery of a minimum amount of the bactericidal component without weighting the implant.

At present, the team is completing in vitro studies of the obtained coatings and is also working on optimizing the coating method for its future use.

For the first time, scientists have introduced minuscule tracking devices directly into the interior of mammalian cells, giving an unprecedented peek into the processes that govern the beginning of development.

This work on one-cell embryos is set to shift our understanding of the mechanisms that underpin cellular behaviour in general, and may ultimately provide insights into what goes wrong in ageing and disease.

The research, led by Professor Tony Perry from the Department of Biology and Biochemistry at the University of Bath in the UK, involved injecting a silicon-based nanodevice together with sperm into the egg cell of a mouse. The result was a healthy, fertilised egg containing a tracking device.

The tiny devices are a little like spiders, complete with eight highly flexible 'legs'. The legs measure the 'pulling and pushing' forces exerted in the cell interior to a very high level of precision, thereby revealing the cellular forces at play and showing how intracellular matter rearranged itself over time.

The nanodevices are incredibly thin - similar to some of the cell's structural components, and measuring 22 nanometres, making them approximately 100,000 times thinner than a pound coin. This means they have the flexibility to register the movement of the cell's cytoplasm as the one-cell embryo embarks on its voyage towards becoming a two-cell embryo.

"This is the first glimpse of the physics of any cell on this scale from within," said Professor Perry. "It's the first time anyone has seen from the inside how cell material moves around and organises itself."

WHY PROBE A CELL'S MECHANICAL BEHAVIOUR?

The activity within a cell determines how that cell functions, explains Professor Perry. "The behaviour of intracellular matter is probably as influential to cell behaviour as gene expression," he said. Until now, however, this complex dance of cellular material has remained largely unstudied. As a result, scientists have been able to identify the elements that make up a cell, but not how the cell interior behaves as a whole.

"From studies in biology and embryology, we know about certain molecules and cellular phenomena, and we have woven this information into a reductionist narrative of how things work, but now this narrative is changing," said Professor Perry. The narrative was written largely by biologists, who brought with them the questions and tools of biology. What was missing was physics. Physics asks about the forces driving a cell's behaviour, and provides a top-down approach to finding the answer.

"We can now look at the cell as a whole, not just the nuts and bolts that make it."

Mouse embryos were chosen for the study because of their relatively large size (they measure 100 microns, or 100-millionths of a metre, in diameter, compared to a regular cell which is only 10 microns [10-millionths of a metre] in diameter). This meant that inside each embryo, there was space for a tracking device.

The researchers made their measurements by examining video recordings taken through a microscope as the embryos developed. "Sometimes the devices were pitched and twisted by forces that were even greater than those inside muscle cells," said Professor Perry. "At other times, the devices moved very little, showing the cell interior had become calm. There was nothing random about these processes - from the moment you have a one-cell embryo, everything is done in a predictable way. The physics is programmed."

The results add to an emerging picture of biology that suggests material inside a living cell is not static, but instead changes its properties in a pre-ordained way as the cell performs its function or responds to the environment. The work may one day have implications for our understanding of how cells age or stop working as they should, which is what happens in disease.

The study is published this week in Nature Materials and involved a trans-disciplinary partnership between biologists, materials scientists and physicists based in the UK, Spain and the USA.

The study is published this week in Nature Materials and involved a trans-disciplinary partnership between embryologists in Bath and the USA led by Professor Perry, and materials scientists and physicists led by Professor José Antonio Plaza at the Instituto de Microelectrónica de Barcelona (IMB-CNM) in Spain.

Scientists at the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) report a breakthrough in developing a next-generation thermochromic window that not only reduces the need for air conditioning but simultaneously generates electricity.

Heat generated by sunlight shining through windows is the single largest contributor to the need for air conditioning and cooling in buildings. Because residential and commercial buildings use 74% of all electricity and 39% of all energy in the United States, the shading effect from tinting windows helps buildings use less energy.

The technology, termed "thermochromic photovoltaic," allows the window to change color to block glare and reduce unwanted solar heating when the glass gets warm on a hot, sunny day. This color change also leads to the formation of a functioning solar cell that generates on-board power. Thermochromic photovoltaic windows can help buildings turn into energy generators, increasing their contribution to the broader energy grid's needs. The newest breakthrough now enables myriad colors and a broader range of temperatures that drive the color switch. This increases design flexibility for improving energy efficiency as well as control over building aesthetics that is highly desirable for both architects and end users.

The research builds upon earlier work at NREL into a thermochromic window that darkened as the sun heated its surface. As the window shifted from transparent to tinted, perovskites embedded within the material generated electricity. Perovskites are a crystalline structure shown to have remarkable efficiency at harnessing sunlight.

"A prototype window using the technology could be developed within a year," said Bryan Rosales, a postdoctoral researcher at NREL and lead author of the paper, "Reversible Multicolor Chromism in Layered Formamidinium Metal Halide Perovskites," which appears in the journal Nature Communications. His co-authors from NREL are Lance Wheeler, who developed the first thermochromic photovoltaic window, Taylor Allen, David Moore, Kevin Prince, Garry Rumbles, and Laura Schelhas. Other authors are Laura Mundt from SLAC National Accelerator Laboratory, and Colin Wolden from Colorado School of Mines.

The first-generation solar window was able to switch back and forth between transparent and a reddish-brown color, requiring temperatures between 150 degrees and 175 degrees Fahrenheit to trigger the transformation. The latest iteration allows a broad choice of colors and works at 95 degrees to 115 degrees Fahrenheit, a glass temperature easily achieved on a hot day.

By using a different chemical composition and materials, the researchers also were able to rapidly speed up the color transformation. The time was reduced to about seven seconds from the three minutes it took during the proof-of-concept thermochromic photovoltaic window demonstrated in 2017.

The scientists sandwiched a thin perovskite film between two layers of glass and injected vapor. The vapor triggers a reaction that causes the perovskite to arrange itself into different shapes, from a chain to a sheet to a cube. The colors emerge with the changing shapes. Lowering the humidity returns the perovskite to its normal transparent state.

A model that can calculate a person's risk of becoming infected and then seriously ill due to COVID-19 has been shown to accurately estimate risk during the first wave of the pandemic in England, in new research funded by the National Institute for Health Research (NIHR).

The model, developed using routine anonymised data from more than 8 million adults in 1205 general practices across England, uses a number of factors such as a person's age, ethnicity and existing medical conditions to predict their risk of catching COVID-19 and then dying or being admitted to hospital.

The model has the potential to provide doctors and the public with more nuanced information about risk of serious illness due to COVID-19, and to help patients and doctors reach a shared understanding of risk, within the context of individual circumstances, risk appetite and the sorts of preventative measures people can take in their daily lives.

Throughout the pandemic, new information has emerged about what factors may influence whether someone is seriously affected by COVID-19, creating an opportunity to develop a detailed risk prediction model.

Researchers at the University of Oxford and collaborators across the UK have used anonymous data from primary care, hospitals, COVID-19 test results and death registries to determine which factors were associated with poor outcomes during the first wave of COVID-19.

This data was used to create a risk prediction model - QCovid - that provides a weighted, cumulative calculation of risk using the variables associated with poor COVID-19 outcomes. The factors incorporated in the model include age, sex, ethnicity, level of deprivation, obesity, whether someone lived in residential care or was homeless, and a range of existing medical conditions, such as cardiovascular disease, diabetes, respiratory disease and cancer.

This model was then tested in two independent sets of anonymised data, from January to April 2020 and from May 2020 to June 2020, to find out whether it accurately predicted severe outcomes due to COVID-19 during the first wave of the pandemic in England.

The research results, published in the BMJ, showed that the model performed well in predicting outcomes. People in the dataset whose calculated risk put them in the top 20% of predicted risk of death accounted for 94% of deaths from COVID-19.

Lead researcher Professor Julia Hippisley-Cox, a general practitioner and Professor of Clinical Epidemiology and General Practice at University of Oxford's Nuffield Department of Primary Care Health Sciences, said: "Risk assessments to date have been based on the best evidence and clinical expertise, but have focused largely on single factors. The QCovid risk model provides a much more nuanced assessment of risk by taking into account a number of different factors that are cumulatively used to estimate risk."

"This model will help inform clinical advice so that people can take proportionate precautions to protect themselves from COVID-19."

The researchers plan to regularly update their model as levels of immunity change, more data become available and behaviour in the population changes, so that the model could also be used to support risk stratification for public health purposes as the infection rate changes over time.

The research was funded by the NIHR following a commission by the Chief Medical Officer for England.

Deputy Chief Medical Officer for England Dr Jenny Harries said: "Continuing to improve our understanding of the virus and how it affects different members of the population is vital as prevalence continues to rise.

"This is why we commissioned and funded this research, and I'm pleased it is providing useful evidence to help us move towards a more nuanced understanding of COVID-19 risk.

"We are working at pace and will maintain our ongoing engagement with patients, the healthcare profession and the voluntary sector on how we use this knowledge to ensure we continue protecting and supporting the most clinically vulnerable."

The research team is led by the University of Oxford and includes researchers from the universities of Cambridge, Edinburgh, Swansea, Leicester, Nottingham and Liverpool with the London School of Hygiene & Tropical Medicine, Queen's University Belfast, Queen Mary University of London, University College London, the Department of Health and Social Care, NHS Digital and NHS England.

Professor Jonathan Valabhji, National Clinical Director for Diabetes and Obesity at NHS England, said: "Along with other characteristics like age and ethnicity, the evidence shows that both diabetes and obesity are risk factors for COVID-19 and this risk prediction tool has the potential to much more accurately gauge risk for each individual, drawing together all of their relevant characteristics and ultimately helping them to stay as safe as possible during this pandemic."

Researchers at the University of Cincinnati have identified new clues into ways tobacco use impacts patients with kidney cancer.

The study, published in the Journal of Clinical Investigation, provides the first steps in developing personalized treatments for patients with this type of cancer.

Expanding on previous work that identified the mutations of kidney cancer cells, this study reveals metabolic fingerprints that distinguish cancers from nonsmokers compared to smokers.

"Standard analysis of mutations may not have detected the effects of tobacco smoking in kidney cancer, so these results and this study provides important steps toward new and better therapeutic strategies for kidney cancers in both smoking and nonsmoking populations," says Maria Czyzyk-Krzeska, MD, PhD, professor in the UC Department of Cancer Biology.

The disease studied, called "clear cell renal cell carcinoma," is the most common type of kidney cancer, but there are few chemotherapy options for advanced cancers, she says.

A multidisciplinary team of UC researchers led by Czyzyk-Krzeska in Cancer Biology, Jarek Meller, PhD, in Environmental and Public Health Sciences, and Julio Landero Figueroa, PhD, in Chemistry, analyzed tissues of patients who were tobacco users as well as those who were not, uncovering the widespread effects of smoking in this form of kidney cancer.

"Importantly, this integrated approach was key to identifying the major metabolic reprogramming in energy and biosynthesis, associated with the presence of cadmium and inorganic arsenic found in cigarettes, together with a distinct signature of copper in tumors from tobacco smokers," says Maria Czyzyk-Krzeska.

The data show that tumors from longtime smokers represent a separate metabolic subtype of kidney cancer with different weaknesses and which could require a dedicated treatment strategy.

"There is a need for an in-depth analysis of metabolic subtypes of these cancers to establish the best way to treat each individual tumor," she says. "This is one of the earliest studies to establish that this type of analysis is necessary. Personalized, or precision medicine, has the promise of offering a specific and unique therapy based on the molecular landscape of each patient's cancer.

"This has huge potential to change outcomes for patients, leading to better and longer lives."

A cutting-edge technique that allows scientists to zoom into tiny details in a 3D image of a whole animal heart may lead to new insights on congenital heart disease.

Surgery and other interventions can help repair structural heart defects in many of the 1% of infants born with congenital heart disease. But 10-25% of these children still do not survive their first year and 44% do not survive to age 18. The new technique, originally described in a paper posted on bioRxiv* and now published in eLife, reveals defects in cells and the components within them found in hearts affected by congenital heart disease. This may lead to treatments to correct these defects and further improve survival.

When pumping blood, the chambers of the heart fill up and then contract to push the blood back out into circulation. To efficiently contract, the heart cells and tiny muscle fibers inside them must be precisely organised.

"When the heart is diseased or has defects, this organisation can be lost or partially lost, and the heart may no longer pump blood efficiently, leading to complications and even death," explains lead author Graham Rykiel, MS, a biomedical engineer who conducted the study as a graduate student in a research team led by senior author Sandra Rugonyi at Oregon Health & Science University (OHSU), Portland, Oregon, US.

By combining two imaging techniques, 3D microcomputed tomography and 3D scanning electron microscopy, the OHSU team was able to create high-resolution, 3D images of the whole heart of a chicken embryo, and zoom in to study the organisation within the heart cells. They then used this tool to examine the differences in cells and the structures within them between a healthy, normal developing chicken heart and one with a defect called tetralogy of Fallot, a relatively common form of congenital heart disease in humans. This revealed structural differences between cellular components within the healthy chicken heart and the heart with the defect.

"Our imaging technology will allow us to study exactly what happens within the heart and its cells when the heart has a defect or is diseased," Rykiel says. "This knowledge will give us clues to design better treatments for patients with heart defects and other anomalies."

The technique will be useful for studying normal heart development in chickens and other animals, and how factors such as drugs or environmental differences might influence congenital heart disease - a focus of Rugonyi's group for over 15 years. This in turn may help explain how tiny structural differences in the heart cells can cause heart problems or heart failure in people with congenital heart disease even after a successful surgery.

"By using our imaging technology on chicks with heart defects, we can start to understand how hearts from human babies with similar defects differ from normal hearts and what needs to be done beyond surgery to repair them and avoid their failure," concludes senior author Sandra Rugonyi, PhD, Professor of Biomedical Engineering at OHSU.

About 30 years ago, Dr. Richard Sifers set out on a journey to discover why people with a rare condition known as alpha1-antitrypsin (AAT) deficiency present with high variation in the severity of liver disease. His journey led him to the discovery of fundamental underpinnings of this condition and, unexpectedly, to uncovering a novel cellular mechanism for disposing of misfolded proteins. The latter has implications not just for AAT-deficiency, but also for other more common conditions associated with accumulation of defective proteins, including neurological disorders, such as Alzheimer's disease.

AAT deficiency can develop in people who carry the AAT gene with a mutation called Z.

"I began studying AAT deficiency because I was intrigued by the wide range of severity of the condition. Some of the people carrying two copies of the Z mutation developed lung disease late in life and some developed liver disease. Interestingly, the condition also could appear very early in life. Some newborns and infants developed severe liver disease and needed to have a transplant to live," said Sifers, professor of pathology & immunology and member of the Dan L Duncan Comprehensive Cancer Center at Baylor College of Medicine.

Other groups had shown that about 1 in 1,700 people carry two copies of the AAT-Z gene. However, only about 17 percent of these newborns with AAT-Z had clinically significant liver disease, and less than 3 percent of those progressed to life-threatening, end-stage disease as infants.

One of Sifers's first contributions was to help develop the first screening test to determine whether a newborn was at risk of developing severe liver disease.

"Developing the screening method made me realize that I could tell whether a child was at a high risk of having liver disease, but still did not know what was causing the condition," Sifers said.

Understanding AAT-deficiency

AAT is a protein produced by the liver and transported through the blood to the lungs, where it protects them from damage caused by other enzymes that breakdown proteins in the lung. The Z mutation produces a defective AAT protein that cannot fold into an appropriate 3-D conformation. Inappropriately folded AAT-Z proteins cannot exit the liver, so they do not travel to the lungs to protect them from destruction. This can lead to lung damage contributing to emphysema and other lung conditions.

"As I studied the disease, I noticed that AAT-Z, which should be released from the liver, was actually accumulating," Sifers said. "This suggested that the naturally disposing mechanism of the cell might not be working."

Sifers and others dug deeper into how cells dispose of misfolded proteins. They discovered that cells shuttle defective proteins from their place of synthesis, the endoplasmic reticulum (ER), to the cytosol, where they are degraded in a cellular structure called a proteasome. Key to this process is to tag the proteins for destruction.

"We showed that removing certain sugars from proteins would flag them for degradation," Sifers said. "Specifically, we found that the human enzyme mannosidase Man1b1 acted like a quality-control factor that mediated the removal of the sugar mannose from misfolded AAT-Z proteins, promoting their degradation."

The AAT deficiency model has been used by many other researchers studying conditions also linked to toxic accumulation of misfolded proteins in cells, altogether called conformational diseases. This approach has accelerated the understanding of the underlying causes of these conditions, offering novel opportunities for potential treatments.

Connecting Man1b1 and AAT deficiency-associated liver disease in infants

Although researchers knew that liver injury associated with AAT deficiency was linked to accumulation of misfolded AAT-Z proteins in the liver, there was still no explanation for the severe liver disease in infants.

In a 2009 paper, Sifers and his colleagues studied liver tissue samples from unrelated infants or children older than 2 years who had undergone liver transplantation for end-stage liver disease. They also conducted genetic linkage and functional laboratory experiments with other cells cultured in the lab.

They showed that certain genetic modification, a single nucleotide polymorphism, that leads to changes in the expression of the Man1b1 gene results in lower levels of Man1b1protein in the endoplasmic reticulum of liver cells.

Sifers and colleagues proposed that lower levels of Man1b1 impair the liver's capacity to deal with the accumulation of misfolded AAT-Z. This likely accelerates reaching the tolerable threshold for protein accumulation, resulting in earlier liver failure.

Having AAT-Z and a genetic variant that slows down the disposal of misfolded AAT-Z proteins can explain the condition in the youngest patients.

"I was delighted that after years of research, we had found an explanation for the mystery of AAT deficiency-associated liver disease in infants and wondered whether my lab would make other major contributions in the future," Sifers said.

Man1b1 has more than one role

As Sifers and colleagues continued studying Man1b1, they unexpectedly came across a role for this protein that had not been described before.

"We found that, in addition to tagging misfolded proteins for degradation by enzymatically removing mannose groups, Man1b1 also promotes protein degradation by another mechanism that is independent from the first," Sifers said.

Sifers and his co-authors, Dr. Ashlee H. Sun, now at Polypus-transfection Biotechnology, and Dr. John R. Collette, postdocs in his lab, reported in the Proceedings of the National Academy of Sciences, U.S.A., that the conventional enzymatic removal system resides in one side of Man1b1, the C-terminal domain. In contrast, the new unconventional system is controlled by the other side of Man1b1, the N-terminal domain. Further studies will elucidate whether and how both systems operate in synergy.

The researchers propose that the new unconventional system might be involved in the elimination of soluble protein aggregates that have been associated with conformational diseases. For instance, human Man1b1 has been linked to the causes of multiple congenital disorders of intellectual disability and HIV infection, and to poor prognosis in patients with bladder cancer.

"Our work is a clear example that studying rare diseases can bring solutions for more common conditions."

By investigating a rare liver disease in babies, we have stumbled upon a pathway that could possibly be targeted to prevent more common neurological disorders occurring in late age," Sifers said.

Weather forecasters can more accurately predict when a tornado is likely to hit the UK thanks to a new tool devised in a partnership between the University of Leeds and the Met Office.

Around 30 tornadoes occur in the UK each year, 40% of which develop on cold fronts - but a lack of forecasting methods for these conditions means they strike without warning.

Now researchers at Leeds and the Met Office have for the first time created a prediction for how likely tornadoes are to occur on cold fronts, meaning a more accurate assessment of tornado risk can be made before a cold front crosses the UK.

Matthew Clark, a Met Office scientist who is currently studying for a PhD at Leeds's School of Earth and Environment, said: "Tornadoes are a relatively common weather hazard on UK cold fronts, but the Met Office have never before had any way of predicting which cold fronts are likely to produce tornadoes, nor did we understand why tornadoes occurred in some fronts but not others.

"These findings should help to improve the UK forecasts of localised, intense wind damage associated with these kinds of weather system. This should enable organisations and people to take precautions and minimise damage and risk."

Mr Clark and Douglas Parker, Professor of Meteorology at Leeds' School of Earth and Environment, analysed tornado reports from the Tornado and Storm Research Organisation (TORRO), radar imagery and surface analysis charts from 114 weather events over a 35 year period. One such event was the largest tornado outbreak in European history when 104 tornadoes touched down across England and Wales on 23 November, 1981, leaving a trail of damage in their wake.

The researchers identified patterns across the weather events, establishing which cold fronts were likely to produce a single tornado, which could produce several, and which would produce none. The research found that most of these tornadoes form when a region of strong winds approaches the front from the cold side. This creates a bulge in the front which helps to make it sharper, increasing the contrast in wind speed and direction across the front. Where this contrast increases over time, tornadoes are more likely to "spin up" along the front. Occasionally, relatively large outbreaks of tornadoes can occur in this situation. Forecasters can recognise these weather patterns, which alert them to the general risk of a tornado.

Clark and Parker also used their findings to create a predictive tool, which is already being used on an experimental basis by the Met Office to pinpoint regions at increased risk of tornadoes. Using the wind fields ahead and behind the cold front, forecasters can now compute a percentage probability that tornadoes will happen.

The tool is currently being tested in the Met Office, and was put to use on 29 February this year, successfully predicting the risk of tornadoes in southeast England, with a tornado occurring in Kent as the cold front swept through during the morning. Although use of the product is experimental at the moment, it is hoped that in time it will allow for appropriate messaging to be issued to local responders and other organisations such as airports.

Met Office Chief Meteorologist Paul Davies said: "By explaining, for the first time, "how" and "why" tornadoes form in a given weather system, meteorologists are much better prepared to anticipate events in advance, to interpret and challenge the results of numerical weather prediction models, and to communicate their confidence in a given forecast."

ITHACA, N.Y. - If an initial COVID-19 vaccine is about as effective as a flu shot, uptake by the American public may fall far short of the 70% level needed to achieve herd immunity, new Cornell research suggests.

In surveys of nearly 2,000 American adults, barely half said they would be willing to take a hypothetical vaccine with an efficacy, or effectiveness, of 50% - the U.S. Food and Drug Administration's minimum threshold for a COVID-19 vaccine, and comparable to flu vaccines.

Vaccine acceptance increased by 10 percentage points, to 61%, if its effectiveness increased to 90%, making efficacy among the most important factors in Americans' willingness to adopt a COVID-19 vaccine, the research found.

"Our results suggest that 50% efficacy will lead to significant vaccine hesitancy," said Douglas Kriner, professor of government at Cornell. "We might not get enough people to take it at that level, even though it would be a valuable public health intervention."

Kriner and Sarah Kreps, professor of government at Cornell, conducted surveys in July asking respondents to choose between hypothetical COVID-19 vaccines based on four medical factors: efficacy, duration of protection and the chances of major or minor side effects.

They also analyzed how political factors influenced vaccine acceptance, including if it was fully approved by the FDA or made available through an Emergency Use Authorization; if it was developed in the United States, United Kingdom or China; and if it was endorsed by President Donald Trump, former Vice President Joe Biden, the U.S. Centers for Disease Control and Prevention or the World Health Organization.

Survey respondents evaluated pairs of vaccines with varying profiles, expressing a preference for one or neither. They then reported their willingness to take each vaccine individually.

Along with improved efficacy, vaccine acceptance improved with a longer protection duration (five years vs. one year) and a lower incidence of major side effects, but by smaller margins (2% and 4%, respectively).

Politically, average willingness to receive a vaccine was lowest when endorsed by Trump, at 52%, but only slightly better for Biden at 55%. Uptake was stronger when endorsements came from U.S. or global public health institutions, improving to 58% for the WHO and 59% for the CDC.

Geopolitics also mattered: Americans' 60% average willingness to receive a vaccine developed in the U.S. dropped slightly if the vaccine came from the U.K. and significantly if it came from China, an outcome that appeared more plausible when the survey was conducted in July, the authors said.

Even one of the best-case hypothetical vaccines presented - developed in the U.K. and approved by the FDA with 90% efficacy, five years of protection, few side effects and CDC endorsement - barely reached the estimated threshold for herd immunity, with 71% of Americans willing to take it.

Kriner and Kreps said the findings can help public health authorities and political leaders develop appropriate endorsements, incentives and messages to broaden vaccine uptake.