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In 2001, the famous herpetologist Joseph B. Slowinski died from snakebite by an immature black-and-white banded krait, while leading an expedition team in northern Myanmar. The very krait that caused his death is now confirmed to belong to the same species identified as a new to science venomous snake, following an examination of samples collected between 2016 and 2019 from Yingjiang County, Yunnan Province, China.

The new krait species, found in Southwestern China and Northern Myanmar, is described by Dr Zening Chen of Guangxi Normal University, PhD candidate Shengchao Shi, Dr Li Ding from the Chengdu Institute of Biology at the Chinese Academy of Sciences, Dr Gernot Vogel of the Society for Southeast Asian Herpetology in Germany and Dr Jingsong Shi of the Institute of Vertebrate Paleontology and Paleoanthropology at Chinese Academy of Sciences. Their study is published in the open-access, peer-reviewed journal ZooKeys.

The researchers decided to name the new species Bungarus suzhenae - Suzhen's krait, after the mythical figure of Bai Su Zhen - a powerful snake goddess from the traditional Chinese myth 'Legend of White Snake'.

The legend says that, after thousands of years of practicing magic power, the white snake Bai Su Zhen transformed herself into a young woman and fell in love with the human man Xu Xian. Together, they ran a hospital, saving lots of human lives with medicine and magic. However, this love between goddess and human was forbidden by the world of the gods and, eventually, Bai Su Zhen was imprisoned in a tower for eternity. Since then, the Chinese regard her as a symbol of true love and good-heartedness.

"The black-and-white banded krait is one of the snakes most similar to the white snake in nature, so we decided to name it after Bai Su Zhen," say the authors.

In fact, the discovery of Suzhen's krait was inspired by another accident from 2015, when the Chinese herpetologist Mian Hou was bitten by a black-and-white banded krait in Yingjiang. "It hurt around the wound, and the skin around it turned dark," said the unfortunate man, who luckily survived.

The authors of the present study realized that the bite was different from those of the many-banded krait B. multicinctus, which go without clear symptoms or pain around the wound. This clue eventually led to the discovery of Suzhen's krait.

Because kraits are highly lethal, understanding their species diversity and geographic distribution is vital for saving human lives. Thanks to adequate description and classification of deadly snakes, research on venom, antivenom development and proper snakebite treatment can advance more rapidly.

The new study makes it easier to distinguish between krait species from China and adjacent southeastern Asia. "Three species of the black-and-white banded kraits from China were previously put under the same name - many-banded krait, which would hinder appropriate medical treatment," the authors point out. Additionally, they suggest that antivenom for the many-banded krait be reevaluated accordingly.

A new paper in the Journal of General Internal Medicine published by the GenderSci Lab at Harvard University shows that Black women are dying at significantly higher rates than white men, and that disparities in mortality rates among women of all races are greater than those between white women and white men.

The study is the first to quantify the inequities in COVID-19 mortality looking at both race and sex group.

"This analysis complicates the simple narrative that men are dying at greater rates of COVID-19 than women," said lead author Tamara Rushovich, Harvard Ph.D. candidate in population health sciences and lab member at the GenderSci Lab.

Results show that the common belief that men with COVID-19 fare more poorly than women varies in magnitude across social groups defined by race/ethnicity.

Key findings of the study include:

Black women have COVID-19 mortality rates that are almost 4 times higher than that of white men and 3 times higher than that of Asian men, as well as higher than white and Asian women.

Black men have far higher mortality rates than any other sex and racial group, including over 6 times higher than the rate among white men.

The disparity in mortality rates between Black women and white women is over 3 times the disparity between white men and white women.

The disparity between Black men and Black women is larger than the disparity between white men and white women.

It is well understood that racism and social inequities, not genetics, are responsible for racial disparities in COVID-19 mortality. However, many researchers focus on differences in biology to explain the sex disparity in COVID-19 mortality. This paper's findings challenge the sole focus on biology as an explanation for sex differences in COVID-19 mortality and argue that societal factors related to gender in combination with racism and socioeconomic stratification are important explanatory factors.

Researchers at the Human Genome and Stem Cell Research Center (HUG-CELL), hosted by the University of São Paulo's Institute of Biosciences (IB-USP) in Brazil, have developed a technique to reconstruct and produce livers in the laboratory.

The proof-of-concept study was conducted with rat livers. In the next stage of their research, the scientists will adapt the technique for the production of human livers in order in future to increase the supply of these organs for transplantation.

The study was supported by FAPESP and is reported in an article published in Materials Science and Engineering: C.
"The plan is to produce human livers in the laboratory to scale. This will avoid having to wait a long time for a compatible donor and reduce the risk of rejection of the transplanted organ," Luiz Carlos de Caires-Júnior, first author of the article, told Agência FAPESP. He is a postdoctoral fellow of HUG-CELL, one of the Research, Innovation and Dissemination Centers (RIDCs) funded by FAPESP.

The methodology is based on decellularization and recellularization, tissue bioengineering techniques developed in recent years to produce organs for transplantation. An organ from a deceased donor, in this case the liver, is treated with various solutions containing detergents or enzymes to remove all the cells from the tissue, leaving only the extracellular matrix with the organ's original structure and shape. The extracellular matrix is then seeded with cells taken from the patient. The technique avoids immune system reactions and the risk of rejection in the long term.

"It's comparable to transplanting a 'reconditioned' liver. It won't be rejected because it uses the patient's own cells, and there's no need to administer immunosuppressants," said Mayana Zatz, HUG-CELL's principal investigator and last author of the article.

The technique can also be used to reconstitute organs considered borderline and non-transplantable, increasing the supply of organs for patients on the waiting list, Caires-Júnior explained.

"Many organs available for transplantation can't actually be used because the donor has died in a traffic accident. The technique can be used to repair them, depending on their status," he said.

The decellularization process, however, removes the main components of the extracellular matrix, such as molecules that tell the cells to multiply and form blood vessels, for example. This weakens cell adhesion to the extracellular matrix and compromises recellularization.

To surmount this obstacle, the HUG-CELL researchers enhanced the technique by introducing an extra stage between decellularization and recellularization.

After isolating and decellularizing rat livers, they injected into the extracellular matrix a solution rich in molecules such as SPARC and TGFB1, proteins produced by liver cells grown in a laboratory in a conditioned medium. These proteins are essential to a healthy liver as they tell liver cells to proliferate and form blood vessels.

"Enrichment of the extracellular matrix with these molecules lets it become much more similar to that of a healthy liver," Caires-Júnior said.

Rat liver extracellular matrices were treated with the solution, and hepatocytes, endothelial cells, and mesenchymal cells were introduced into the material. The mesenchymal cells were derived from human induced pluripotent stem cells (iPSCs), produced by reprogramming adult skin cells (or cells from other easily accessible tissues) into an embryonic-like pluripotent state.

"The study shows it's possible to induce human stem cell differentiation in cell lineages that are part of a liver and use these cells to reconstruct the organ so that it's functional. It's proof of concept, the first demonstration that the technique works," Zatz said.

The liver cells were injected with a syringe pump into rat liver extracellular matrices to produce an organ with human characteristics. It grew for five weeks in an incubator that simulated the conditions in the human body. Analysis showed that extracellular matrix enrichment with SPARC and TGFB1 significantly improved recellularization.

"The treatment made the liver cells grow and function more vigorously," Caires-Júnior said. "We plan to build a bioreactor to decellularize human livers and study the possibility of producing them to scale in the laboratory."

The technique can be adapted to produce other organs, such as lungs, hearts, and skin, he added.

Organ factories

The project is part of one of the research lines pursued by HUG-CELL to produce or reconstruct transplant organs using different techniques.

Through a project conducted in partnership with pharmaceutical company EMS and supported by FAPESP (São Paulo Research Foundation) under the auspices of its Research Partnership for Technological Innovation Program (PITE), the HUG-CELL researchers aim to modify pig organs such as kidneys, hearts and skin for transplantation into humans (read more at: agencia.fapesp.br/29771/).

Pig livers would be rejected if they were transplanted into humans, so the researchers are pursuing other strategies, such as 3D printing (read more at: agencia.fapesp.br/32217/), as well as decellularization and recellularization.

"These are complementary approaches. We expect to see transplant organ factories in future," Zatz said.

Overfishing likely did not cause the Atlantic cod, an iconic species, to evolve genetically and mature earlier, according to a study led by Rutgers University and the University of Oslo - the first of its kind - with major implications for ocean conservation.

"Evolution has been used in part as an excuse for why cod and other species have not recovered from overfishing," said first author Malin L. Pinsky, an associate professor in the Department of Ecology, Evolution, and Natural Resources in the School of Environmental and Biological Sciences at Rutgers University-New Brunswick. "Our findings suggest instead that more attention to reducing fishing and addressing other environmental changes, including climate change, will be important for allowing recovery. We can't use evolution as a scapegoat for avoiding the hard work that would allow cod to recover."

The study, which focuses on Atlantic cod (Gadus morhua) off Newfoundland in Canada and off Norway, appears in the journal Proceedings of the National Academy of Sciences.

In the Northwest Atlantic Ocean, cod range from Greenland to Cape Hatteras, North Carolina. In U.S. waters, cod is most common on Georges Bank and in the western Gulf of Maine, but both fish stocks are overfished. Cod can reach 51 inches long, weigh up to 77 pounds and live more than 20 years. Early explorers named Cape Cod in Massachusetts for the species because it was so abundant off New England, according to the National Oceanic and Atmospheric Administration.

Many debates over the last few decades have centered on whether cod have evolved in response to fisheries, a phenomenon known as fisheries-induced evolution. Cod now mature at a much earlier age, for example. The concern has been that if the fish have evolved, they may not be able to recover even if fishing is reduced, according to Pinsky.

Cod populations with late-maturing individuals can produce more offspring and more effectively avoid predators, he said. They are also better protected against climate variability, more stable and less likely to collapse.

Both theory and experiments suggest that fishing can lead to an earlier maturation age. But prior to the new study, no one had tried to sequence whole genomes from before intensive fishing to determine whether evolution had occurred. So, scientists sequenced cod earbones and scales from 1907 in Norway, 1940 in Canada and modern cod from the same populations. The northern Canadian population of cod collapsed from overfishing in the early 1990s, while the northeast Arctic population near Norway faced high fishing rates but smaller declines, the study says.

"We found that cod likely did not evolve in response to fisheries," Pinsky said. "There were no major losses in genetic diversity and no major changes that suggested intensive fishing induced evolution. We cannot entirely rule out that evolution happened, but it's more likely that the fish are developing earlier as a response to their environment and would be able to develop and mature later if the environment changes, benefiting the species."

The scientists' findings complement conclusions from literature reviews and evolutionary modeling that the direct impacts of fisheries on populations and ecosystems are a more pressing concern than the effects of fisheries-induced evolution, the study says. Avoiding overfishing and reducing fishing pressure when populations become low remain a key management strategy.

"A big question is whether other species, especially those with shorter lifespans, may show signs of evolution, in contrast to the long-lived cod," Pinsky said. "We are investigating this by DNA sequencing 100-year-old specimens from the Smithsonian National Museum of Natural History."

A growing body of evidence suggests that biodiversity loss increases our exposure to both new and established zoonotic pathogens. Restoring and protecting nature is essential to preventing future pandemics. So reports a new Proceedings of the National Academy of Sciences (PNAS) paper that synthesizes current understanding about how biodiversity affects human health and provides recommendations for future research to guide management.

Lead author Felicia Keesing is a professor at Bard College and a Visiting Scientist at Cary Institute of Ecosystem Studies. She explains, "There's a persistent myth that wild areas with high levels of biodiversity are hotspots for disease. More animal diversity must equal more dangerous pathogens. But this turns out to be wrong. Biodiversity isn't a threat to us, it's actually protecting us from the species most likely to make us sick."

Zoonotic diseases like COVID-19, SARS, and Ebola are caused by pathogens that are shared between humans and other vertebrate animals. But animal species differ in their ability to pass along pathogens that make us sick.

Rick Ostfeld is a disease ecologist at Cary Institute and a co-author on the paper. He explains, "Research is mounting that species that thrive in developed and degraded landscapes are often much more efficient at harboring pathogens and transmitting them to people. In less-disturbed landscapes with more animal diversity, these risky reservoirs are less abundant and biodiversity has a protective effect."

Rodents, bats, primates, cloven-hooved mammals like sheep and deer, and carnivores have been flagged as the mammal taxa most likely to transmit pathogens to humans. Keesing and Ostfeld note, "The next emerging pathogen is far more likely to come from a rat than a rhino."

This is because animals with fast life histories tend to be more efficient at transmitting pathogens. Keesing explains, "Animals that live fast, die young, and have early sexual maturity with lots of offspring tend to invest less in their adaptive immune responses. They are often better at transmitting diseases, compared to longer-lived animals with stronger adaptive immunity."

When biodiversity is lost from ecological communities, long-lived, larger-bodied species tend to disappear first, while smaller-bodied species with fast life histories tend to proliferate. Research has found that mammal hosts of zoonotic viruses are less likely to be species of conservation concern (i.e. they are more common), and that for both mammals and birds, human development tends to increase the abundance of zoonotic host species, bringing people and risky animals closer together.

"When we erode biodiversity, we favor species that are more likely to be zoonotic hosts, increasing our risk of spillover events," Ostfeld notes. Adding that, "Managing this risk will require a better understanding of how things like habitat conversion, climate change, and overharvesting affect zoonotic hosts, and how restoring biodiversity to degraded areas might reduce their abundance."

To predict and prevent spillover, Keesing and Ostfeld highlight the need to focus on host attributes associated with disease transmission rather than continuing to debate the prime importance of one taxon or another. Ostfeld explains, "We should stop assuming that there is a single animal source for each emerging pathogen. The pathogens that jump from animals to people tend to be found in many animal species, not just one. They're jumpers, after all, and they typically move between species readily."

Disentangling the characteristics of effective zoonotic hosts - such as their immune strategies, resilience to disturbance, and habitat preferences - is key to protecting public health. Forecasting the locations where these species thrive, and where pathogen transmission and emergence are likely, can guide targeted interventions.

Keesing notes, "Restoration of biodiversity is an important frontier in the management of zoonotic disease risk. Those pathogens that do spill over to infect humans--zoonotic pathogens--often proliferate as a result of human impacts." Concluding, "As we rebuild our communities after COVID-19, we need to have firmly in mind that one of our best strategies to prevent future pandemics is to protect, preserve, and restore biodiversity."

CHICAGO - A new study shows that youth arrested as juveniles with psychiatric disorders that remain untreated, struggle with mental health and successful outcomes well beyond adolescence.

Research from Northwestern Medicine shows nearly two-thirds of males and more than one-third of females with one or more existing psychiatric disorders when they entered detention, still had a disorder 15 years later.

The findings are significant because mental health struggles add to the existing racial, ethnic and economic disparities as well as academic challenges from missed school, making a successful transition to adulthood harder to attain.

"Kids get into trouble during adolescence.Those from wealthier families also use drugs and get into fights. But these situations are most often handled informally by the school and parent, and don't culminate in arrest and detention," said lead author Linda Teplin, Owen L. Coon Professor of psychiatry and behavioral sciences at Northwestern University Feinberg School of Medicine.

"These are not necessarily bad kids, but they have many strikes against them. Physical abuse, sexual abuse and neglect are common. These experiences can precipitate depression. Incarceration should be the last resort," said Teplin, also a faculty associate with the University's Institute for Policy Research.

The unprecedented longitudinal study reports on the prevalence, persistence and patterns of behavioral and psychiatric disorders in youth up to 15 years after they leave detention and whether outcomes vary by sex and race/ethnicity.

Key findings show that despite a decrease in disorders over time, especially among females, the prevalence of psychiatric disorders 15 years later was still substantially higher than the general population.

Males fared significantly worse overall. Among youth with a disorder in detention, 64.3% of males and 34.8% of females had one or more disorders 15 years later. Compared with females, males had more than three times the odds of persisting with a psychiatric disorder over time.

"This may be because females, as they age, became more family-focused. Positive social connections - having a stable partner, raising children, establishing a family - are conducive to positive mental health," said study co-author Karen Abram, professor of psychiatry and behavioral sciences at Feinberg School of Medicine and associate director of the Program in Health Disparities and Public Policy.

Fifteen years after youth left detention, disruptive behavior and substance abuse disorders were the most common. Non-Hispanic whites had 1.6 times greater odds of having behavioral disorders and more than 1.3 times greater odds of having substance use disorders throughout the follow-up period compared with African Americans and Hispanics.

"An unanticipated finding of the study was the lower rate of substance use disorders in racial/ethnic minorities, despite the disproportionate incarceration of these groups," Teplin said.

"Clearly, we must expand mental health services during detention and when these youth return to their communities. We must also encourage pediatricians and educators to advocate for early identification and treatment of psychiatric disorders," Teplin said. "Unfortunately, in the U.S., school systems are funded by local governments. Thus, our children may be sentenced to a life of inequity because of their zip code."

"Prevalence, Comorbidity, and Continuity of Psychiatric Disorders in Delinquent Youth After Detention: A 15-Year Prospective Longitudinal Study," will publish in JAMA Pediatrics at 11 a.m. EST, April 5, 2021.

In addition to Teplin and Abram, Northwestern co-authors include Lauren M. Potthoff, David A. Aaby, Leah J. Welty and Mina K. Dulcan.

About the Northwestern Juvenile Project:

Seeing a gap in the research literature about the health needs and outcomes of juvenile justice youth, the Northwestern Juvenile Project, a Northwestern Medicine initiative, has been interviewing a randomly selected sample of 1,800 youth since the mid-1990s.

To date, the study has compiled epidemiological data from 16,372 face-to-face interviews, conducted from a median age of 15 at detention through the median age of 31. The researchers assess 13 psychiatric disorders and track the prevalence, patterns of multiple disorders and the continuity of disorders over time. The study also focuses on gender and racial/ethnic differences.

Project data has been used to analyze health issues, including firearm violence, mortality, drug abuse and HIV/AIDS risk behaviors. Project data also found that few participants achieved positive outcomes in adulthood, such as finishing high school or finding steady employment.

What The Study Did: The 30-day incidence of outpatient and hospital-associated blood clots following SARS-CoV-2 testing among adults in a large health system was examined in this study.

Authors: Nareg H. Roubinian, M.D., of Kaiser Permanente Northern California in Oakland, is the corresponding author.

To access the embargoed study: Visit our For The Media website at this link https://media.jamanetwork.com/

(doi:10.1001/jamainternmed.2021.0488)

Editor's Note: The article includes conflicts of interest and funding/support disclosures. Please see the article for additional information, including other authors, author contributions and affiliations, conflict of interest and financial disclosures, and funding and support.

More snow is melting during winter across the West, a concerning trend that could impact everything from ski conditions to fire danger and agriculture, according to a new University of Colorado Boulder analysis of 40 years of data.

Researchers found that since the late 1970s, winter's boundary with spring has been slowly disappearing, with one-third of 1,065 snow measurement stations from the Mexican border to the Alaskan Arctic recording increasing winter snowmelt. While stations with significant melt increases have recorded them mostly in November and March, the researchers found that melt is increasing in all cold season months--from October to March.

Their new findings, published today in Nature Climate Change, have important implications for water resource planning and may indicate fewer pristine powder days and crustier snow for skiers.

"Particularly in cold mountain environments, snow accumulates over the winter--it grows and grows--and gets to a point where it reaches a maximum depth, before melt starts in the spring," said Keith Musselman, lead author on the study and research associate ,at the Institute of Arctic and Alpine Research (INSTAAR) at the University of Colorado Boulder.

But the new research found that melt before April 1 has increased at almost half of more than 600 stations in western North America, by an average of 3.5% per decade.

"Historically, water managers use the date of April 1 to distinguish winter and spring, but this distinction is becoming increasingly blurred as melt increases during the winter," said Noah Molotch, co-author on the study, associate professor of geography and fellow at INSTAAR.

Snow is the primary source of water and streamflow in western North America and provides water to 1 billion people globally. In the West, snowy mountains act like water towers, reserving water up high until it melts, making it available to lower elevations that need it during the summer, like a natural drip irrigation system.

"That slow trickle of meltwater that reliably occurs over the dry season is something that we have built our entire water infrastructure on in the West," said Musselman. "We rely very heavily on that water that comes down our rivers and streams in the warm season of July and August."

More winter snowmelt is effectively shifting the timing of water entering the system, turning that natural drip irrigation system on more frequently in the winter, shifting it away from the summer, he said.

This is a big concern for water resource management and drought prediction in the West, which depends heavily on late winter snowpack levels in March and April. This shift in water delivery timing could also affect wildfire seasons and agricultural irrigation needs.

Wetter soils in the winter also have ecological implications. One, the wet soils have no more capacity to soak up additional water during spring melt or rainstorms, which can increase flash flooding. Wetter winter soils also keep microbes awake and unfrozen during a time they might otherwise lay dormant. This affects the timing of nutrient availability, water quality and can increase carbon dioxide emissions.

An underutilized data source

Across the western U.S., hundreds of thin, fluid-filled metal pillows are carefully tucked away on the ground and out of sight from outdoor enthusiasts. These sensors are part of an extensive network of long-running manual and automated snow observation stations, which you may have even used data from when looking up how much snow is on your favorite snowshoeing or Nordic skiing trail.

This new study is the first to compile data from all 1,065 automated stations in western North America, providing valuable statistical insight into how mountain snow is changing.

And by using automated, continuously recording snowpack stations instead of manual, monthly observations, the new research shows that winter melt trends are very widespread--at three-times the number of stations with snowpack declines, according to Musselman.

Snowpack is typically measured by calculating how much water will be produced when it melts, known as snow-water equivalent (SWE), which is affected by how much snow falls from the sky in a given season. But because winter snowpack melt is influenced more by temperature than by precipitation, it is a better indicator of climate warming over time.

"These automated stations can be really helpful to understand potential climate change impacts on our resources," said Musselman. "Their observations are consistent with what our climate models are suggesting will continue to happen."

Three years ago, scientists at the University of Michigan discovered an artificial photosynthesis device made of silicon and gallium nitride (Si/GaN) that harnesses sunlight into carbon-free hydrogen for fuel cells with twice the efficiency and stability of some previous technologies.

Now, scientists at the Department of Energy's (DOE's) Lawrence Berkeley National Laboratory (Berkeley Lab) - in collaboration with the University of Michigan and Lawrence Livermore National Laboratory (LLNL) - have uncovered a surprising, self-improving property in Si/GaN that contributes to the material's highly efficient and stable performance in converting light and water into carbon-free hydrogen. Their findings, reported in the journal Nature Materials, could help radically accelerate the commercialization of artificial photosynthesis technologies and hydrogen fuel cells.

"Our discovery is a real game-changer," said senior author Francesca Toma, a staff scientist in the Chemical Sciences Division at the Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab). Usually, materials in solar fuels systems degrade, become less stable and thus produce hydrogen less efficiently, she said. "But we discovered an unusual property in Si/GaN that somehow enables it to become more efficient and stable. I've never seen such stability."

Previous artificial photosynthesis materials are either excellent light absorbers that lack durability; or they're durable materials that lack light-absorption efficiency.

But silicon and gallium nitride are abundant and cheap materials that are widely used as semiconductors in everyday electronics such as LEDs (light-emitting diodes) and solar cells, said co-author Zetian Mi, a professor of electrical and computer engineering at the University of Michigan who invented Si/GaN artificial photosynthesis devices a decade ago.

When Mi's Si/GaN device achieved a record-breaking 3 percent solar-to-hydrogen efficiency, he wondered how such ordinary materials could perform so extraordinarily well in an exotic artificial photosynthesis device - so he turned to Toma for help.

HydroGEN: Taking a Team Science approach to solar fuels

Mi had learned of Toma's expertise in advanced microscopy techniques for probing the nanoscale (billionths of a meter) properties of artificial photosynthesis materials through HydroGEN, a five-national lab consortium supported by the DOE's Hydrogen and Fuel Cell Technologies Office, and led by the National Renewable Energy Laboratory to facilitate collaborations between National Labs, academia, and industry for the development of advanced water-splitting materials. "These interactions of supporting industry and academia on advanced water-splitting materials with the capabilities of the National Labs are precisely why HydroGEN was formed - so that we can move the needle on clean hydrogen production technology," said Adam Weber, Berkeley Lab's Hydrogen and Fuel Cell Technologies Lab Program Manager and Co-Deputy Director of HydroGEN.

Toma and lead author Guosong Zeng, a postdoctoral scholar in Berkeley Lab's Chemical Sciences Division, suspected that GaN might be playing a role in the device's unusual potential for hydrogen production efficiency and stability.

To find out, Zeng carried out a photoconductive atomic force microscopy experiment at Toma's lab to test how GaN photocathodes could efficiently convert absorbed photons into electrons, and then recruit those free electrons to split water into hydrogen, before the material started to degrade and become less stable and efficient.

They expected to see a steep decline in the material's photon absorption efficiency and stability after just a few hours. To their astonishment, they observed a 2-3 orders of magnitude improvement in the material's photocurrent coming from tiny facets along the "sidewall" of the GaN grain, Zeng said. Even more perplexing was that the material had increased its efficiency over time, even though the overall surface of the material didn't change that much, Zeng said. "In other words, instead of getting worse, the material got better," he said.

To gather more clues, the researchers recruited scanning transmission electron microscopy (STEM) at the National Center for Electron Microscopy in Berkeley Lab's Molecular Foundry, and angle-dependent X-ray photon spectroscopy (XPS).

Those experiments revealed that a 1 nanometer layer mixed with gallium, nitrogen, and oxygen - or gallium oxynitride - had formed along some of the sidewalls. A chemical reaction had taken place, adding "active catalytic sites for hydrogen production reactions," Toma said.

Density functional theory (DFT) simulations carried out by co-authors Tadashi Ogitsu and Tuan Anh Pham at LLNL confirmed their observations. "By calculating the change of distribution of chemical species at specific parts of the material's surface, we successfully found a surface structure that correlates with the development of gallium oxynitride as a hydrogen evolution reaction site," Ogitsu said. "We hope that our findings and approach - a tightly integrated theory-experiments collaboration enabled by the HydroGEN consortium - will be used to further improve the renewable hydrogen production technologies."

Mi added: "We've been working on this material for over 10 years - we know it's stable and efficient. But this collaboration helped to identify the fundamental mechanisms behind why it gets more robust and efficient instead of degrading. The findings from this work will help us build more efficient artificial photosynthesis devices at a lower cost."

Looking ahead, Toma said that she and her team would like to test the Si/GaN photocathode in a water-splitting photoelectrochemical cell, and that Zeng will experiment with similar materials to get a better understanding of how nitrides contribute to stability in artificial photosynthesis devices - which is something they never thought would be possible.

"It was totally surprising," said Zeng. "It didn't make sense - but Pham's DFT calculations gave us the explanation we needed to validate our observations. Our findings will help us design even better artificial photosynthesis devices."

"This was an unprecedented network of collaboration between National Labs and a research university," said Toma. "The HydroGEN consortium brought us together - our work demonstrates how the National Labs' Team Science approach can help solve big problems that affect the entire world."

Thousands of our daily activities, from making coffee to taking a walk to saying hello to a neighbor, are made possible through an ancient collection of brain structures tucked away near the center of the cranium.

The cluster of neurons known as the basal ganglia is a central hub for regulating a vast array of routine motor and behavior functions. But when signaling in the basal ganglia is weakened or broken, debilitating movement and psychiatric disorders can emerge, including Parkinson's disease, Tourette's syndrome, attention deficit hyperactivity disorder (ADHD) and obsessive-compulsive disorder.

Despite its central importance in controlling behavior, the specific, detailed paths across which information flows from the basal ganglia to other brain regions have remained poorly charted. Now, researchers at the University of California San Diego, Columbia University's Zuckerman Institute and their colleagues have generated a precise map of brain connectivity from the largest output nucleus of the basal ganglia, an area known as the substantia nigra pars reticulata, or SNr. The findings offer a blueprint of the area's architecture that revealed new details and a surprising level of influence connected to the basal ganglia.

The results, spearheaded by Assistant Project Scientist Lauren McElvain and carried out in the Neurophysics Laboratory of Professor David Kleinfeld at UC San Diego, and the laboratory of Zuckerman Institute Principal Investigator Rui Costa, are published April 5 in the journal Neuron.

The research establishes a new understanding of the position of the basal ganglia in the hierarchy of the motor system. According to the researchers, the newly identified pathways emerging from the connectivity map could potentially open additional avenues for intervention of Parkinson's disease and other disorders tied to the basal ganglia.

"With the detailed circuit map in hand, we can now plan studies to identify the specific information conveyed by each pathway, how this information impacts downstream neurons to control movement and how dysfunction in each output pathway leads to the diverse symptoms of basal ganglia diseases," said McElvain.

With support from the NIH's Brain Research through Advancing Innovative Neurotechnologies® (BRAIN) Initiative, the researchers developed the new blueprint working in mice by applying a modern neuroscience toolset that combines techniques from genetics, virus tracing, automated microscopic imaging of whole-brain anatomy and image processing. The results revealed surprising new insights about the breadth of connections.

"These results are an example of how researchers supported by the BRAIN Initiative are using the latest brain mapping tools to change in a fundamental way our understanding of how the connections in the brain's circuits are organized," said John J. Ngai, director of the NIH's BRAIN Initiative.

Previous work had emphasized that the basal ganglia architecture is dominated by a closed-loop with output projections connecting back to input structures. The new study reveals the SNr broadcasts even to lower levels of the motor and behavior system. This includes a large set of brainstem regions with direct connections to the spinal cord and motor nuclei that control muscles via a small number of intervening connections.

"The new findings led by Dr. McElvain offer an important lesson in motor control," said Kleinfeld, a professor in the Division of Biological Sciences (Section of Neurobiology) and Division of Physical Sciences (Department of Physics). "The brain does not control movement though a hierarchy of commands, like the 'neural networks' of self-driving cars, but through a scheme of middle management that directs motor output while informing the executive planners."

Remarkably, according to the researchers, the SNr neurons that project to the low levels of the motor system have branched axons that simultaneously project back up to the brain regions responsible for higher-order control and learning. In this way, the newly described connectivity of SNr neurons fundamentally links operations across high and low levels of the brain.

"The fact that specific basal ganglia output neurons project to specific downstream brain nuclei but also broadcast this information to higher motor centers has implications for how the brain chooses which movements to do in a particular context, and also for how it learns about which actions to do in the future," said Costa, a professor of neuroscience and neurology at Columbia's Vagelos College of Physicians and Surgeons, as well as director and chief executive officer of the Zuckerman Institute.

The diffraction limit, also known as Abbe diffraction limit in optics, poses a great challenge in many systems that involve wave dynamics, such as imaging, astronomy, and photolithography. For example, the best optical microscope only possesses resolution around 200 nm, but the physical size of the photolithography process with an excimer laser is around tens of nanometers. Meanwhile, physical sizes in current research and applications in biology and the semiconductor industry have scaled down to several nanometers, which is far beyond the ability of optical waves. According to the Abbe theory, subwavelength features are usually associated with evanescent waves, which decay exponentially with distance from the target. In response to this problem, researchers have developed many ways to bypass the Abbe limit, showing success in different applications. In one instance, the 2014 Nobel Prize in Chemistry was awarded to Eric Betzig, Stefan W. Hell, and William E. Moerner, for their contributions to the development of super-resolved fluorescence microscopy for life-sciences research.

Currently, there are two main approaches to overcoming the diffraction limit in optics: near-field and far-field. The near-field approach utilizes a nanosized tip scanning over the sample and directly interacts with those evanescent fields. As a scanning approach, it provides high-fidelity images but is always time-consuming. On the other hand, far-field approaches, such as stimulated emission depletion microscopy (STED), stochastic optical reconstruction microscopy (STORM), and structured illumination microscopy (SIM), are based on fluorescent labeling, restricting them from broader applications--for instance, in the semiconductor industry. A more fundamental approach is needed--one that is free from near-field scanning and nanofabrication as well as fluorophores.

A team of researchers from Shanghai Jiao Tong University recently developed an alternative way to break the Abbe diffraction limit and realize subwavelength imaging in an all-optical manner. As reported in Advanced Photonics, they propose localized evanescent-wave illuminations, which are excited at the silicon surface by four-wave mixing, a third-order nonlinear optical process. Such excited waves help to realize super-resolution through the way that they scatter part of the evanescent fields of the target into the far field. By varying wave vectors of excited waves, parts of different orientations in Fourier spectrum can then be obtained. Combined with an iterative reconstruction technique called Fourier ptychography, these multiple Fourier-spectral parts can be stacked together, recovering an enlarged Fourier spectrum that includes evanescent fields--thereby realizing super-resolution imaging in the far field.

Probing the evanescent waves around a target, the team realizes label-free, nonscanning subwavelength imaging in the far field. The authors note that their results also show promise for a new type of high-resolution photolithography mechanism: constructive interference of such excited near-field evanescent waves can focus light into tiny spots well below the diffraction limit.

EAST LANSING, Mich. - Nine of the hottest years in human history have occurred in the past decade. Without a major shift in this climate trajectory, the future of life on Earth is in question, which poses a new question: Should humans, whose fossil fueled society is driving climate change, use technology to put the brakes on global warming?

Michigan State University community ecologist Phoebe Zarnetske is co-lead of the Climate Intervention Biology Working Group, a team of internationally recognized experts in climate science and ecology that is bringing science to bear on the question and consequences of geoengineering a cooler Earth.

The group's paper, "Potential ecological impacts of climate intervention by reflecting sunlight to cool Earth," was published in the most recent issue of Proceedings of the National Academy of Sciences of the United States, or PNAS.

"There is a dearth of knowledge about the effects of climate intervention on ecology," said Zarnetske, associate professor in the Department of Integrative Biology in the MSU College of Natural Science and the paper's lead author. "As scientists, we need to understand and predict the positive and negative effects it could have on the natural world, identify key knowledge gaps and begin to predict what impacts it may have on terrestrial, marine and freshwater species and ecosystems if it were adopted in the future."

Conversations in 2018 between Jessica Gurevitch, Distinguished Professor in the Department of Ecology and Evolution at Stony Brook University and working group co-lead, and Alan Robock, Distinguished Professor in the Department of Environmental Sciences at Rutgers University, gave rise to the pioneering group, which is more aware than most that geoengineering Earth's atmosphere is more than just a science fiction scenario.

The costs and technology needed to reflect the sun's heat back into space are currently more attainable than other climate intervention ideas like absorbing carbon dioxide from the air. The working group anticipates its discussions and open access paper will encourage an explosion of scientific investigation into how a climate intervention strategy known as solar radiation modification, or SRM, in tandem with greenhouse gas emissions reduction, would affect the natural world.

The feasibility of planetary wide SRM efforts hinge on accurate predictions of its myriad outcomes provided by the well-established computer simulations of the Geoengineering Model Intercomparison Project, or GeoMIP. The PNAS paper lays the foundation for expanding GeoMIP's scope to include the incredible range and diversity of Earth's ecosystems.

"While climate models have become quite advanced in predicting climate outcomes of various geoengineering scenarios, we have very little understanding of what the possible risks of these scenarios might be for species and natural systems," Gurevitch said. "Are the risks for extinction, species community change and the need for organisms to migrate to survive under SRM greater than those of climate change, or does SRM reduce the risks caused by climate change?"

"Most of the GeoMIP models only simulate abiotic variables, but what about all of the living things that are affected by climate and rely on energy from the sun?" Zarnetske said, who is also a faculty member of MSU's Ecology, Evolution and Behavior Program. "We need to better understand the possible impacts of SRM on everything from soil microorganisms to monarch butterfly migrations to marine systems."

Zarnetske's Spatial and Community Ecology Lab, or SpaCE Lab, specializes in predicting how ecological communities respond to climate change across scales from the microcosm to the global, making it uniquely poised to assist the working group in illuminating vital data for future SRM scenarios such as stratospheric aerosol intervention, or SAI, the focus of the paper.

SAI would reduce some of the sun's incoming radiation by reflecting sunlight back into space, such as what happens after large volcanic eruptions. Theoretically, it would be possible to continuously replenish the cloud and control its thickness and location to achieve a desired target temperature.

But the paper reveals the under researched complexity of cascading relationships between ecosystem function and climate under different SAI scenarios. In fact, the scientists argue that climate change mitigation must continue regardless of whether SRM is adopted, and the question remains whether some or any SRM can be beneficial in addition to decarbonization efforts.

"Although SAI may cool Earth's surface to a global temperature target, the cooling may be unevenly distributed, affecting many ecosystem functions and biodiversity," Zarnetske said. "Rainfall and surface ultraviolet radiation would change, and SAI would increase acid rain and would not mitigate ocean acidification."

In other words, SRM is not a magic bullet for solving climate change. Until the working group's efforts inspire new research into the effects of different climate intervention scenarios, SRM is more akin to a shot in the dark.

"Participating in this working group has been quite eye-opening for me," said Peter Groffman, ecosystem ecologist and professor at the Advanced Science Research Center at the CUNY Graduate Center and the Cary Institute of Ecosystem Studies. "I was unaware that modeling climate intervention was so advanced, and I think that climate modelers were unaware of the complexities of the ecological systems being affected. It is a strong reminder of the importance of the need for multidisciplinary analysis of complex problems in environmental science."

"We hope that this paper will spark a lot more attention to this issue and greater cooperation between scientists in the fields of climate science and ecology," Gurevitch said.

DURHAM, N.C. - A devastating itching of the skin driven by severe liver disease turns out to have a surprising cause. Its discovery points toward possible new therapies for itching, and shows that the outer layer of the skin is so much more than insulation.

The finding, which appears April 2 in Gastroenterology, indicates that the keratinocyte cells of the skin surface are acting as what lead researcher Wolfgang Liedtke, MD PhD, calls 'pre-neurons.'

"The skin cells themselves are sensory under certain conditions, specifically the outermost layer of cells, the keratinocytes," said Liedtke, who is a professor of neurology at Duke School of Medicine.

This study on liver disease itching, done with colleagues in Mexico, Poland, Germany and Wake Forest University, is a continuation of Liedtke's pursuit of understanding a calcium-permeable ion channel on the cell surface called TRPV4, which he discovered 20 years ago at Rockefeller University.

The TRPV4 channel plays a crucial role in many tissues, including the sensation of pain. It was known to exist in skin cells, but nobody knew why.

"The initial ideas were that it plays a role in how the skin is layered, and in skin barrier function," Liedtke said. "But this current research is getting us into a more exciting territory of the skin actually moonlighting as a sensory organ." Once a chemical signal of itching is received, keratinocytes relay the signal to nerve endings in the skin that belong to itch-sensing nerve cells in the dorsal root ganglion next to the spine.

"Dr. Liedtke and I had a longstanding interest in the role of TRPV4 in the skin, based on our previous collaborations we decided to focus on chronic itch," said Yong Chen, and assistant professor of neurology at Duke who is first author on the study.

The researchers found that in a liver disease called primary biliary cholangitis (PBC), patients are left with a surplus of lysophosphatidylcholine (LPC) a phosphorylated lipid, or fat, circulating in the blood stream. They then demonstrated that LPC, injected into the skin of mice and monkeys, evokes itch.

Next they wanted to understand how this lipid could lead to the aggressive itching sensation. "If the itch comes up in PBC, it's so debilitating that the patients might need a new liver. That's how bad it can get," Liedtke said. Importantly, the skin is not chronically inflamed in PBC, meaning there is debilitating itch in the absence of chronic skin inflammation.

The researchers found that when LPC reaches the skin, the lipid can bind directly to TRPV4. Once bound, it directly activates the ion channel to open the gate for calcium ions, which are a universal switch mechanism for many cellular processes.

But in this case, the signal does something surprising. The researchers followed a signaling cascade inside the cell in which one molecule hands off to another, resulting in the formation of a tiny bubble back on the skin cell's surface called a vesicle. Vesicles are designed to bud off cells and carry whatever is inside them away.

In this case, the bubbles contained something surprising: micro-RNA, and it functioned as a signaling molecule. "This is crazy, because microRNAs are normally known to be gene regulators." Liedtke said.

It turns out that this particular bit of microRNA is itself the signal that evokes the itch.

Once they had identified it as microRNA miR-146a, the researchers injected the molecule by itself into mice and monkeys and found that it immediately caused itching, not hours later, as it would if it were regulating genes.

"Future research will address which specific itch sensory neurons respond to miR-146a, beyond the TRPV1-dependent signaling that we have found, also its in-depth mechanism," Chen said.

With the help of German and Polish liver specialists who have blood collections and itch data on PBC patients, the researchers discovered that the blood levels of microRNA-146a corresponded to itch severity, as did the LPC levels.

Knowing all the parts of the signaling that leads from excess phospho-lipid, LPC, to intolerable itching gives scientists a new way to look for advanced liver disease markers, Liedtke said.

And it points to new avenues for treating the itch, either by possibly desensitizing the TRPV4 channels in skin with a topical treatment, attacking the specific microRNAs that drive the itch, or targeted depletion of LPC.

Palmer Amaranth is a high-impact agronomic weed species that has cost the United States agriculture industry billions of dollars since its discovery outside of its native range in the southwestern U.S. and northwestern Mexico. Over the last 20 years, it has moved further north, and now poses a major threat to corn, soybean, and cotton growers across the south and Midwest regions of the United States.

It is not legal to sell any kind of seed in Minnesota if the seed lot contains Palmer Amaranth. The problem is this particular invasive species--which has shown potential to wipe out up to 91% of corn yields, 68% of soybean yields, and 54% of cotton yields-- is difficult to visibly distinguish from other pigweed species, making identification reliant upon genetic testing.

In a recent study published in Pest Management Science, researchers from the University of Minnesota's Minnesota Invasive Terrestrial Plants and Pests Center (MITPPC) and Colorado State University have developed a new test for identifying Palmer Amaranth that is more robust, easier to use, and -- most importantly -- has shown 99.9% accuracy.

Due to rapid spread of herbicide resistance traits in Palmer populations, the prevention of Palmer establishment is more important than ever. Researchers hope to make the new test technology commercially available to agronomic professionals across the United States by the end of 2021, which can be applied to both individual samples and bulk seed mixes.

"Development of tools and weed seed regulations play important roles, but ultimately it all comes back to the growers," said lead author Anthony Brusa, a postdoctoral associate in the College of Food, Agricultural and Natural Resource Sciences. "Prevention of Palmer is a team effort. So far, every initial sighting of Palmer in Minnesota was from a grower, and control efforts wouldn't be possible without their help."

To develop the test, researchers collected samples of Palmer Amaranth and related species from across the United States, as well as Mexico, South America and Africa. They then performed genomic sequencing on these samples and searched for specific genetic differences between species. The targets identified were then used to design a set of three genetic markers for the identification of Palmer DNA against the DNA of related pigweed species. Finally, those tests were validated for performance against the most robust testing panel assembled to date.

"We hope that this will be the first of many molecular diagnostics developed for weed seed testing," said co-author Eric Patterson, an assistant professor and weed geneticist at Michigan State University. "The gates are open for developing tests for herbicide resistance, seed contamination, and seed bank diversity."

Accuracy for these markers ranged from 99.7%-99.9%, with only one-to-three errors against a panel of 1,250 samples. Bulk seed testing showed reliable detection of Palmer at a level of one Palmer seed in a mix of 200 pigweed seeds.

"We believe this has the potential to help prevent Palmer seed from being introduced as a contaminant in pollinator seed mixes, bird seed, and other seed lots sold from areas where Palmer is currently a problem, into areas like Minnesota," said co-author Todd Gaines, an associate professor of molecular weed science at Colorado State University. "We also see great potential for this to be used to help protect corn and soybean exports by verifying the absence of Palmer in grain sold to countries that won't accept Palmer-contaminated products."

In the immediate future, the research team continues to investigate novel approaches for Palmer control, and are currently investigating the potential use of genomic testing to identify Palmer presence in soil seed banks.

"The development of these new markers and their commercialization will provide new options to seed companies labeling seed for sale in Minnesota as well as other industries that may be at risk for introducing Palmer Amaranth via screenings, hay, equipment, or feed," said Denise Thiede, section manager for seed, noxious weed, hemp, and biotechnology at the Minnesota Department of Agriculture.

How do we become a complex, integrated multicellular organism from a single cell?

While developmental biologists have long researched this fundamental question, Stanford University biologist and HHMI investigator Dominique Bergmann's recent work on the plant Arabidopsis thaliana has uncovered surprising answers.

In a new study, published April 5 in Developmental Cell, led by Bergmann and postdoctoral scholar Camila Lopez-Anido, researchers used single-cell RNA sequencing technologies to track genetic activity in nearly 20,000 cells as they formed the surface and inner parts of an Arabidopsis leaf. Through this highly detailed technique, the researchers captured transient and rare cell states and found a surprising abundance of ambiguity in how cells traversed various identities, particularly early on within the stem cell population.

"All the cells are coordinated, and yet they're all individuals with their own genetic programs," said Bergmann, who is the Shirley R. and Leonard W. Ely, Jr. Professor in the School of Humanities and Sciences and senior author of the study. "And so we're really working to appreciate that balance between seeing what's new and special and unique about each one while also recognizing how they are working together."

While many scientists in this field focus on fruit flies and roundworms, some aspects of biological development will only be understood by studying other organisms - such as the plant Arabidopsis thaliana, which is the Bergmann lab's specialty.

"As we think about flexibility and resilience in the face of a changing world, we want to learn more about how organisms can manage to build functional bodies when they are under stress or exposed to extreme environments," said Lopez-Anido, who is lead author of the study. "This requires research with organisms that have flexible and tunable lifestyles, such as the plants we study."

As part of a family of artists, Lopez-Anido also embraced a uniquely artistic perspective to interpret and share this research. Within the paper itself, she used a pointillism-inspired analysis software to elegantly organize and visualize her massive dataset. Additionally, her sister, artist Virginia Lopez-Anido, created artwork inspired by Camila's research, which will be featured on the cover of Developmental Cell.

Surprising details

While previous experiments on Arabidopsis had worked out some of the important genes and steps in making specialized cells, this new cell-by-cell data fills in additional details of development. The researchers found, for example, that cells might double-back on the developmental path they seemed to be following, and that it was also possible to jump ahead. They also noticed that there may be differences in the way new stem cells regulated transitions between cell types relative to old stem cells; and whereas they had previously known of core steps in cell differentiation, they saw there were actually many small, seemingly continuous steps along the way.

One especially intriguing finding concerns a crucial gene, called SPEECHLESS, that plays a role in the formation of pores, called stomata, through which the plant exchanges gases and regulates water content. The Bergmann lab has studied SPEECHLESS extensively, but the new data hinted that it was expressed for a longer stretch of the developmental process than they expected. In a follow-up experiment, the researchers were able to selectively remove the gene after it completed its known role but sooner than the new data said it was done being expressed. Sure enough, the developmental programs went off track - and the researchers are now working to figure out why.

"It was a contradiction of what we thought we knew and it was really exciting," Bergmann said. "It makes us want to dig in to other unexpected details - what might look like insignificant blips in the data - and see what we've missed."

Bergmann credits Lopez-Anido and this work with inspiring several avenues of research, including reconsidering what it means to be a stem cell, reframing events that define final differentiation stages and reevaluating what it means to be born as a cell on the top versus bottom of a leaf.

Art, science and mentorship

Analyzing cell identities from nearly 20,000 cells - and 30,000 genes - required machine learning algorithms. So, Lopez-Anido created an organizational framework built around one of the most widely used analysis tools, which is called Seurat after pointillist painter Georges Seurat. As in pointillism, individual dots, which represented individual cells and their specific gene expression signatures, blended together in visualizations that enabled the researchers to see large-scale trends.

Virginia Lopez-Anido visualized Camila's work in another way. She developed a drawing series on the nature of scientific inquiry (Untitled, pencil on paper, 8.5 x 11.7in, 2021), as well as a clay model series of tissue landscapes inspired by scanning electron microscope images of stomata (Untitled, digital photograph, 2021), which is the art that will grace the cover of Developmental Cell.

"I like to engage with artists and scholars across disciplines because it can bring new layers of meaning to science - and make science more accessible, which is very important to me," said Camila Lopez-Anido, who has taught scientific literacy at Bard College through their Citizen Science program and will soon begin work as an assistant professor of biology at Reed College. "I'm looking forward to fostering more of these meaningful research experiences and collaborations for my mentees."