Brain

Irvine, CA - January 27, 2021 - A new University of California, Irvine-led study finds a new method for identifying biomarkers may aid in early cancer diagnosis. The study focused on lung cancer, however the Cell Heterogeneity-Adjusted cLonal Methylation (CHALM) method has been tested on aging and Alzheimer's diseases as well and is expected to be effective for studying other diseases.

"We found the CHALM method may be a valuable tool in helping researchers to identify more reliable differentially methylated genes from sequence-based methylation data," said Wei Li, PhD, the Grace B. Bell chair and professor of bioinformatics in the Department of Biological Chemistry at the UCI School of Medicine. "For clinicians, this method may aid in cancer diagnosis by helping them identify more useful biomarkers, which are overlooked by the traditional method."

Published in Nature Communications, the study, titled, "Cellular Heterogeneity-Adjusted cLonal Methylation (CHALM) improves prediction of gene expression," illustrates the importance of considering cell heterogeneity when calculating the DNA methylation level from sequencing data.

"After applying our CHALM method to a lung cancer dataset, we were able to identify more reliable and biological functions-related differentially methylated genes. Applying our CHALM method may lead to better early cancer detection," said Li.

Using traditional methods for identifying cancer biomarkers, researchers have consistently found the correlation between gene expression and promoter methylation to be weak, especially for low methylated genes. This new study found the CHALM method allowed for more reliable identification of methylated markers that cannot be detected by traditional methods.

The rapid growth of e-cigarette use is a major public health problem in the United States - with significant attention on use among adolescents and young adults. Although manufacturers of e-cigarettes tout their products as safer alternatives to cigarette smoking, research has shown that e-cigarettes can be as hazardous as traditional tobacco products but appeal to those who were never cigarette smokers.

In the first study to assess national use of e-cigarettes among adults with disabilities, George Mason University's College of Health and Human Services researchers found that adults with disabilities were twice as likely to use e-cigarettes (8.4%) than adults without disabilities (4.8%), but the prevalence of e-cigarette use varied by type of disability.

Dr. Gilbert Gimm led the study published in Disability and Health Journal.

"Previous studies have found that e-cigarette use is associated with a greater risk of cardiovascular disease, depression, and adverse health outcomes. Also, smokers with disabilities are less likely to receive advice from their physicians to stop smoking," explains Gimm. "Our study shows that adults with disabilities are a high-risk group for e-cigarette use and therefore at greater risk for adverse health outcomes."

Gimm and colleagues assessed e-cigarette use among 560,858 working age adults (18-64 years) with and without disabilities by using data from the 2017-2018 Behavioral Risk Factor and Surveillance System (BRFSS) survey. With a nationally representative sample, they estimated the prevalence of e-cigarette use among adults by type of disability.

They found that e-cigarette use was more than twice as likely among adults with a cognitive disability (12.0%), an independent living disability (11.0%), or two or more disabilities (9.2%), compared to adults without disabilities (4.8%). Adults with disabilities who were previously smokers were more likely to use e-cigarettes than adults with disabilities who never smoked.

"We know from prior studies that adults with cognitive disabilities have higher rates of mental health conditions such as severe depression and anxiety, and we think this might be a reason for greater e-cigarette use among this population," adds Gimm. "Detailed information on mental health conditions wasn't available in our sample, so we hope future research can shed light on this potential contributor to e-cigarette use in these groups."

Regardless of reported disability status, men were more likely to use e-cigarettes than women, and young adults (18-24 years) were six times as likely use e-cigarettes than middle-aged adults (45-54 years). Adults with COPD or depression were also more likely to use e-cigarettes.

This study highlights the need for more targeted smoking cessation treatments for adults with cognitive disabilities and other high-risk groups. In the future, Gimm and colleagues plan to conduct future research on the use of e-cigarettes among adults with disabilities.

DALLAS (SMU) - Wildfires are the enemy when they threaten homes in California and elsewhere. But a new study led by SMU suggests that people living in fire-prone places can learn to manage fire as an ally to prevent dangerous blazes, just like people who lived nearly 1,000 years ago.

"We shouldn't be asking how to avoid fire and smoke," said SMU anthropologist and lead author Christopher Roos. "We should ask ourselves what kind of fire and smoke do we want to coexist with."

An interdisciplinary team of scientists published a study in the journal Proceedings of the National Academy of Sciences documenting centuries of fire management by Native American farmers. The team included scientists from SMU, the University of Arizona, Harvard University, Simon Fraser University, the US Geological Survey, Baylor University, the University of Illinois, and the University of South Florida.

Jemez people learned how to live with and manage fire long ago

Ancestors of the Native American community in the Jemez Mountains of northern New Mexico lived continuously in fire-prone forests for more than five centuries. Similar to today's communities in the western U.S. forests, Pueblos of the Jemez people had relatively high population densities, and the forested landscape they managed was an area larger than the city of Chicago.

Starting in the 1100s, the Jemez people limited fire spread and improved forest resilience to climate variability by creating purposeful burning of small patches of the forest around their community, researchers found.

"The area around each village would have been a fire-free zone," Roos said. "There were no living trees within two football fields of each village, and the hundreds or thousands of trampling feet mean that fine fuels, such as grasses, herbs, and shrubs, to carry surface fires would have been rare too. The agricultural areas would have seen targeted applications of fire to clean fields after harvest, to recycle plant nutrients as fertilizer, and to clear new fields."

Roos calls those controlled burns "the right kind of fire and smoke." The Jemez practice of burning wood for heat, light, and cooking in their homes also removed much of the fuel that could burn in wildfires, he said.

Roos said the ancient Jemez model could work today. Many communities in the western United States, including those of Native Americans, still rely on wood-burning to generate heat during the winter, he said. Regularly setting small, low-intensity fires in a patchwork around where people live to clear out flammable material would also follow the Jemez model, he said.

"Some sort of public-private tribal partnership might do a lot of good, empowering tribal communities to oversee the removal of the small trees that have overstocked the forests and made them vulnerable to dangerous fires, while also providing wood fuel for people who need it," Roos said.

Since 2018, wildfires have destroyed more than 50,000 structures in California alone. Global warming is only expected to make the amount and severity of wildfires worse.

Almost every major study of fire activity over the last 10,000 years indicates that climate drives fire activity, particular larger fires. Yet, many examples from traditional societies suggest the role of climate can be blunted or buffered by a patchwork of small, purposeful burns before the peak natural fire season. In the Jemez Mountains, the climate influence was weakened and large fires were rare when Jemez farmers used fire preemptively in many small patches, effectively clearing out the materials that fuel today's megafires.

In contrast, today's forests are filled with these young trees, increasing the chances they can generate huge flames and waves of flaming embers that can catch homes on fire.

The scientists used a variety of methods to document how Jemez people handled smoke and fire centuries ago, including interviewing tribal elders at Jemez Pueblo. The team also compared tree-ring fire records with paleoclimate records, which indicated that fire activity was disconnected from climate during the time when Jemez's population was at a peak. In addition, charcoal and pollen records show that Jemez people began using fire to establish an agricultural landscape and to promote habitats for large animals, such as mule deer and elk.

Roos noted that tolerance of fire and smoke hazards probably went hand-in-hand with recognition of the benefits of fire and smoke.

"Paul Tosa, former governor of Jemez Pueblo, said 'Fire brings richness to the land,'" Roos noted. "We could do very well to learn from the wisdom of Jemez peoples and change our relationship to fire and smoke at the wildland-urban interface."

A newly discovered trace fossil of an ancient burrow has been named after University of Alberta paleontologist Murray Gingras. The fossil, discovered by a former graduate student, has an important role to play in gauging how salty ancient bodies of water were, putting together a clearer picture of our planet's past.

"One could not find a more passionate and influential teacher of science in the classroom, in the field or at a conference," said Ryan King, lead author of the study and now an adjunct professor at Western Colorado University.

"Naming the fossil after Gingras was a straightforward decision since his research focuses on tying modern observations of how salinity and substrate affect organism burrowing to ancient burrow appearance and species abundance trends."

Trace fossils are a type of fossil that preserves activity of ancient life in the geological record. They include fossilized footprints, nests, droppings and, in this case, a fossilized burrow dug by an organism that lived in a watery environment.

The fossilized burrow, named Glossifungites gingrasi, is from the late Cretaceous of central Utah and was home to water-dwelling insects, similar to mayflies, more than 90 million years ago.

"Fossils like this are significant because they help us narrow down what type of organism dug the burrow--which in turn will tell us about the salinity of the water in which they lived," said King.

Many organisms make use of burrows for shelter and protection while they feed. These animal-constructed sedimentary structures give researchers a clearer picture of biological communities and are important in understanding ancient rivers, bays, estuaries and oceans through their oxygenation levels and saltiness, King explained.

Murray Gingras, professor in the Department of Earth and Atmospheric Sciences, was the co-advisor for King's doctoral studies and for the master's degree of another researcher on the team, Andrew La Croix, now an assistant professor at the University of Waikato.

"I was surprised and honoured," said Gingras of the recognition. "The graduate student and supervisor relationship is a strong one. Graduate students become the colleagues that you care about the most. Having a graduate student honour you by formally naming a fossil after you is wonderful, because you understand then just how reciprocal the relationship is."

"I have been recognized with a few different awards over the years, but nothing really came close to the pride and elation I felt when Ryan informed me that he and Andrew formally named a trace fossil for me."

The study, "Glossifungites gingrasi n. isp., a probable subaqueous insect domicile from the Cretaceous Ferron Sandstone, Utah," was published in The Journal of Paleontology.

JANUARY 26, 2021, NEW YORK - A study led by Ludwig Chicago Co-director Ralph Weichselbaum and Yang-Xin Fu of the University of Texas Southwestern Medical Center has shown how bacteria in the gut can dull the efficacy of radiotherapy, a treatment received by about half of all cancer patients. Their findings appear in the current issue of the Journal of Experimental Medicine.

"Our study identifies two families of gut bacteria that interfere with radiotherapy in mice and describes the mechanism by which a metabolite they produce--a short chain fatty acid called butyrate--undermines the therapy," said Weichselbaum.

A wide variety of commensal bacteria inhabit the human body, particularly the gut, where they participate in important physiological processes ranging from digestion to regulation of the immune system. Many studies have shown that gut microbes also have a profound influence on cancer therapies, most notably immunotherapies.

Since ionizing radiation is known to activate anti-tumor immune responses, Kaiting Yang, a postdoctoral researcher in Weichselbaum's lab, examined how antibiotics affect the outcomes of tumor radiotherapy.

These studies showed that vancomycin, an antibiotic against gram-positive bacteria, one of two broad classes of bacteria, enhanced responses to tumor irradiation in mice. Gentamycin, which targets gram-negative bacteria, did not have that effect. It turned out that vancomycin's decimation of two families of gram-positive gut bacteria--Lachnospiraceae and Ruminococcaceae--was most closely associated with the improved response. Further analysis revealed that a decline in levels of butyrate, a metabolite produced by these bacteria, accompanied the effect.

When Lachnospiraceae were introduced into mice completely devoid of bacteria, the effect of radiation on their tumors was notably diminished and the dampened response corresponded to a systemic increase in butyrate levels. The injection of butyrate directly into tumors had a similarly dampening effect on radiotherapy.

Since butyrate did not directly protect the tumors from radiation, the researchers turned their attention to the immune response elicited by radiotherapy. Their experiments revealed that butyrate interferes with the activation of cytotoxic (or killer) T cells, immune cells that target cancer cells and are known to attack tumors following radiotherapy.

Previous studies led by Weichselbaum and Fu have shown that irradiation activates a signaling pathway in another immune cell--the dendritic cell, which can prime killer T cells to attack tumors. This biochemical pathway, controlled by a protein named STING, ramps up the dendritic cells' production of immune-stimulating factors known as type-1 interferons (IFN-I), which boosts their activation of killer T cells.

Weichselbaum, Fu, Yang and colleagues show in the current study that butyrate inhibits a step of the biochemical signaling cascade that links STING activation to the production of IFN-I. Adding an IFN-I to tumors simultaneously injected with butyrate restored the therapeutic effects of radiotherapy in the mice.

Their findings confirm and add to those of a study published by other researchers in the Journal of Clinical Investigation in December 2019, which also showed that butyrate compromises the activation of killer T cells by dendritic cells following tumor irradiation.

The current study also has some immediate clinical relevance. The researchers found that levels of other beneficial bacteria (Akkermansia and Lactobacillus) increase in the gut and within tumors of mice following vancomycin treatment. This suggests that butyrate depletion might not be the only mechanism behind the observed improvement in responses to radiotherapy: antibiotic treatment might also affect the microbiome in other ways to support immune responses elicited by radiotherapy.

"Our findings offer clues to the development of new strategies to improve patient responses to radiotherapy," said Weichselbaum. "This includes the specific targeting of particular types of gut bacteria that produce butyrate--once we have a better understanding of the various ways in which these microbes interact with the immune system and cancer therapies."

Our cells are filled with 'bones,' in a sense. Thin, flexible protein strands called actin filaments help support and move around the bulk of the cells of eukaryotes, which includes all plants and animals. Always on the go, actin filaments constantly grow, shrink, bind with other things, and branch off when cells move.

Supercomputer simulations have helped solve the mystery of how actin filaments polymerize, or chain together. This fundamental research could be applied to treatments to stop cancer spread, develop self-healing materials, and more.

"The major findings of our paper explain a property of actin filaments that has been known for about 50 years or so," said Vilmos Zsolnay, co-author of a study published in November 2020 in the Proceedings of the National Academy of Sciences.

Researchers have known for decades that one end of the actin filament is very different from the other end, and that this polarization is needed for the actin filament to function like it needs to. The mystery has been how the filaments used this polarization to grow, shrink, and bind.

"One end of the actin filament elongates much, much faster than the other at a physiological actin protein concentration," Zsolnay said. "What our study shows is that there is a structural basis for the different polymerization kinetics." Vilmos Zsolnay is a graduate student in the Department of Biophysical Sciences at the University of Chicago, developing simulations in the group of Gregory Voth.

"Actin filaments are what give the cell its shape and many other properties," said Voth, the corresponding author of the study and the Haig P. Papazian Distinguished Service Professor at the University of Chicago. Over time, a cell's shape changes in a dynamic process.

"When a cell wants to move forward, for instance, it will polymerize actin in a particular direction. Those actin filaments then push on the cell membrane, which allow the cell to move in a particular direction." Voth said. What's more, other proteins in the cell help align the actin ends that polymerize, or build up more quickly to push in the exact same direction, directing the cell's path.

"We find that one end of the filament has a very loose connection between actin subunits," Zsolnay said. "That's the fast end. The loose connection within the actin polymer allows incoming actin monomers to have access to a binding site, such that it can make a new connection quickly and the polymerization reaction can continue." He contrasted this to the slow end with very tight connections between actin subunits that block an incoming monomer's ability to polymerize onto that end.

Zsolnay developed the study's all-atom molecular dynamics simulation with the Voth Group on the Midway2 computing cluster at the University of Chicago Research Computing Center. He used GROMACS and NAMD software to investigate the equilibrium conformations of the subunits at the filament ends. "This was one of my first projects using a high performance computing cluster," he said.

XSEDE, the NSF-funded Extreme Science and Engineering Discovery Environment, then awarded the scientists allocations on the Stampede2 supercomputer at the Texas Advanced Computing Center. "It was very straightforward to test the code on our local cluster here, and then drop a couple of files onto the machines at Stampede2 to start running again within a day," Zsolnay said.

"The high performance computing clusters of Stampede2 are really what allowed this work to take place," he added. "They were able to reach the time and length scales in our simulations that we were interested in. Without the resources provided by XSEDE, we would not have been able to analyze as large of a dataset or have had as much confidence in our findings."

They ran nine simulations, each of roughly a million atoms propagated for about a microsecond. "There are three nucleotide states that we were interested in - the ATP, the ADP plus the gamma phosphate, and once phosphate is released, it's in an ADP nucleotide state." Zsolnay said.

The simulations showed the smoking gun of the mystery - distinct equilibrium conformations between the barbed end and the pointed end subunits, which led to meaningful differences in the contacts between neighboring actin monomer subunits.

An actin monomer in solution has a conformation that's a little wider than when it's part of a longer actin polymer. The previous model, said Zsolnay, assumed that the wide shape transitions into the flattened shape once it polymerizes, almost discretely.

"What we saw when we started the filament with all of the subunits in the flattened state, the ones at the end relaxed to resemble the monomeric state characterized by a wider shape," Zsolnay explained. "At both of the ends, that same mechanism of the widening of the actin molecule led to very different contacts between subunits." At the fast, barbed end there was a separation between the two molecules. Whereas at the pointed end, there was a very tight connection between them.

Research into actin filaments could find wide-ranging applications, such as improving therapeutics. "What's in the news right now is coronavirus," Voth said, referring to the role of the innate immune system. It involves white blood cells called neutrophils that gobble up bacteria or other pathogens in one's blood stream. "What's critical to their ability to sniff out and seek pathogens is their ability to move through an environment and find the pathogens wherever they are. In the immune response, it's very important," he added

And then there's metastatic cancer, where one or a couple of tumor cells will start to migrate, spreading to other parts of the body. "If you could disrupt that in some way, or make it so that it's not as reliable for your cancerous cells, then you could make a cancer treatment based off of that information," Voth said.

"One angle that Prof. Voth and I find particularly interesting is from a materials science standpoint," said Zsolnay. The amino acids in the actin molecule are roughly the same throughout plants, animals, and yeasts. "That gives a hint to us that there's something special about the material properties of actin molecules that can't be reproduced using a different set of amino acids," he added.

This understanding could help advance development of biomimetic materials that repair themselves. "You can imagine, in the future, a new type of material that heals itself. For instance, if a bucket gets a hole in it, the material could sense that a wound has occurred and heal itself, just like human tissue would," Zsolnay added.

Said Voth: "People are really very keen on biomimetic materials - things that behave like these polymers. Our work is explaining a critical thing, which is the polarization of actin filaments."

What The Study Did: Survey data from school-age children and adolescents in Guangdong province, China, were used to assess self-reported psychological distress associated with the COVID-19 pandemic.

Authors: Chichen Zhang, M.D., and Ruibin Zhang, Ph.D., of Southern Medical University in Guangzhou, and Xuefeng Yi, M.D., of the Health Publicity and Education Center of Guangdong Province, all in China, are the corresponding authors.

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

(doi:10.1001/jamanetworkopen.2020.35487)

Editor's Note: The article includes 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.

An international research team succeeded in gaining new insights into the artificially produced superheavy element flerovium, element 114, at the accelerator facilities of the GSI Helmholtzzentrum für Schwerionenforschung in Darmstadt, Germany. Under the leadership of Lund University in Sweden and with significant participation of Johannes Gutenberg University Mainz (JGU) as well as the Helmholtz Institute Mainz (HIM) in Germany and other partners, flerovium was produced and investigated to determine whether it has a closed proton shell. The results suggest that, contrary to expectations, flerovium is not a so-called "magic nucleus". The results were published in the journal Physical Review Letters.

In the late 1960s, Sven-Gösta Nilsson, then a physics professor at Lund University, and others formulated a theory about the possible existence of still unknown superheavy elements. In the meantime, such elements have been created and many predictions have been confirmed. The discovery of the six new elements 107 to 112 was achieved at GSI in Darmstadt, and further ones up to element 118 are now known as well. Strongly increased half-lives for the superheavy elements due to a "magic" combination of protons and neutrons were also predicted. This occurs when the shells in the nucleus, each holding a certain number of protons and neutrons, are completely filled. "Flerovium, element 114, was also predicted to have such a completed, 'magic' proton shell structure. If this were true, flerovium would lie at the center of the so-called 'island of stability', an area of the chart of nuclides where the superheavy elements should have particularly long lifetimes due to the shell closures," explains Professor Dirk Rudolph of Lund University, who is the spokesperson of the international experiment.

Nilsson's theories inspired the international collaboration led by the Lund group to investigate whether flerovium nuclei indeed exhibit the predicted magical properties. Their experiments, performed at the UNILAC accelerator at GSI in Darmstadt in the framework of the FAIR Phase 0 experimental program, lasted 18 days. Every second, four trillion calcium-48 nuclei with 20 protons were accelerated to ten percent of the speed of light. They irradiated a thin foil containing rare plutonium-244 with 94 protons to produce atomic nuclei of flerovium, which has 114 protons, by nuclear fusion. This so-called target was produced at the Department of Chemistry at JGU, using, plutonium provided, among others, by the Lawrence Livermore National Laboratory, USA. Strong magnets of the GSI recoil separator TASCA separated the flerovium nuclei from the intense calcium ion beam; subsequently they were registered in a detector setup specifically developed in Lund for this experiment.

The detector measured the radioactive decay of 30 flerovium nuclei -- i.e., the emission of nuclear fragments of flerovium -- with high efficiency and accuracy. By precisely analyzing these fragments and their emission times, the team was able to determine unusual decay channels of flerovium nuclei that could not be reconciled with its originally predicted "magical" properties. "Our study shows that element 114 is no more stable than others in its vicinity. This is a very important piece of the puzzle in the continued search for the center of the coveted island of stability," said Professor Christoph Düllmann, professor of nuclear chemistry at JGU and head of the research groups at GSI and HIM.

The new results will be of great benefit to science. Instead of continuing to search for the center of the island of stability in the region of element 114, even heavier ones like the as yet undiscovered element 120, will now move into the spotlight.

As the world prepares to commemorate International Holocaust Remembrance Day on January 27th, communities and memorials around the world are addressing how to meaningfully commemorate the day while protecting public health and safety. The day marking the anniversary of the liberation of Auschwitz is ordinarily commemorated with hundreds of individual memorial events across the globe. This year, most of those events will be impossible for any sizable gathering of people due to COVID-19.

With the goal of proposing relevant solutions to this challenge, Dr. Tobias Ebbrecht-Hartmann and research student Tom Divon of the Hebrew University Communication and Journalism Department, examine the many ways individual museums and memorial sites have adapted their programs over the past year.

As part of the research, Dr. Ebbrecht-Hartmann published in Media, Culture and Society a paper that revealed how educators have successfully leveraged new forms of Holocaust remembrance using social media tools. Included have been a series of memory related hashtags in use on Twitter and Facebook, "live" Instagram stories from memorial sites and concentration camps as well as Zoom discussions with Holocaust survivors across the globe. This transition was described by the author as particularly important because prior to Corona, many memorials objected to such means of communication out of fear that it would "commercialize" or even distort legitimate Holocaust memory.

"The onset of this global crisis has impacted our lives in many ways and indeed Holocaust remembrance is no exception," Dr. Ebbrecht-Hartman said. "While we have already been experiencing a transition where forms of social media and digital content have been increasingly recognized as legitimate expressions of commemoration, the severe restrictions of Corona both accelerated this process but also created a far more accepting culture for the role these media must play."

Ongoing research is compiling data and feedback from 32 Holocaust museums and monuments in nine different countries with the goal of better understanding which digital platforms have been used most effectively and were best received.

The research has so far indicated that educators and museum curators have strived to adapt content to be better absorbed via digital means and in so doing provided the motivation for relevant audiences to log on. Certain museums have opened Instagram and even TikTok accounts, produced online "digital challenges" while others have invested in virtual tours of their facilities. Most of these efforts represent a desire by Holocaust educators to make the history more relevant and accessible to the younger generations who are known to be less emotionally attached to the subject matter.

Among the initiatives described were Yad Vashem's broadcast of their annual commemoration via YouTube in addition to the traditional local television format. The museum also initiated a campaign where online users were invited to read the names of Holocaust victims and then upload them to social media accounts with relevant hashtags.

In a similar approach, the directors of the monument site at the Mauthausen concentration camp in Austria encouraged the public to upload and share pictures or drawings relating to the liberation of the camp with the hashtag #Liberation1945. The monument later released a video clip compiling the images that were uploaded.

Dr. Ebbrecht-Hartmann said, "Even while we are encouraged by these efforts, we know that the physical spaces where the Holocaust occurred will always remain sacred memorial sites. We anticipate that future commemoration will be a continuation of physical trips to these sites but the historic impact of Corona has introduced a new reality whereby digital memorials and online efforts can be an integral component of Holocaust remembrance."

BROOKLYN, New York, Monday, January 26, 2021 - Atomically thin, 2D hexagonal boron nitride (h-BN) is a promising material whose protean ability to undergo phase transformations to strong, super lightweight, chemically stable, oxidation-resistant films makes them ideal for protective coatings, nanotechnology thermal applications, deep-UV light emitters, and much more.

The possibilities embodied in different polytypes of h-BN include the ultra-hard diamond phase, a cubic structure (c-BN) with strength and hardness second only to actual carbon diamonds. Key to fabricating such materials is the ability to induce and control the transformation between their various crystalline phases, in a way that is efficient and cost effective enough to allow for economies of scale.

While synthesizing such materials in their "bulk" or 3D configurations requires immense pressure and heat, researchers at the NYU Tandon School of Engineering have discovered that h-BN in layered, molecule-thin 2D sheets can phase transition to c-BN at room temperature.

In a new study, a team led by Elisa Riedo, Professor of Chemical and Biomolecular Engineering at NYU Tandon, and in collaboration with Remi Dingreville at the Center for Nanotechnologies at Sandia National Laboratories, produced experiments and simulations using a nanoscopic tip compressing atomically thin, 2D h-BN layers to reveal how these room-temperature phase transitions occur and how to optimize them, partly by varying the number of layers in the h-BN thin film.

The research, "Pressure-Induced Formation and Mechanical Properties of 2D Diamond Boron Nitride," whose authors include Angelo Bongiorno, Professor of Chemistry at the City University of New York; Filippo Cellini, former post doc in Riedo's PicoForce Lab at NYU Tandon; Elton Chen of Sandia National Labs; Ryan L. Hartman, an Associate Professor of Chemical and Biomolecular Engineering at NYU Tandon; and Francesco Lavini and Filip Popovic, Ph.D. students in Riedo's lab, appears as the cover story in the Volume 8, Issue 2 of the journal Advanced Science.

"When BN is in the diamond phase, hardness and stiffness increase dramatically, and is, in fact, nearly as hard as a traditional carbon diamond with an improved thermal and chemical stability," said Riedo, "But it cannot normally be found in nature. Formation of cubic boron nitride must be performed in a lab. So we set out to explore the physics and understanding of phase transition from hexagonal to cubic boron nitride in the special case of films that are atomically thin."

Lavini explained that the work involved application of pressure to atomically thin h-BN films with a number of atomic layers from one to ten, using an atomic force microscope (AFM). To test the extent of the phase transition from hexagonal to cubic crystalline structure, the AFM nanoscopic tip probe simultaneously applies pressure and measures the material elasticity.

"A high degree of stiffness demonstrates the phase transition to diamond crystal structure. This is critical because it was not clear before that phase transition could even occur at room temperature," he explained. "Because the whole physics of phase transitions is different in a 2D 'universe' we are discovering and redefining some fundamental materials rules. In this state, for example, the energy barrier to transforming from hexagonal to cubic phase is much smaller."

The experiments and simulations also revealed the optimal thickness to achieve the transition to c-BN: the researchers observed no phase transformation whatsoever in mono-layer h-BN films, while bi-layer and tri-layer films showed 50% increase in stiffness when pressure was applied by the nanoscopic tip, a proxy for the h-BN-to-c-BN phase transition. Above three layers, the researchers observed a diminishing degree of diamond phase transition.

Through simulations -- described in the study -- the collaborators also discovered heterogeneity in the phase transition: instead of spontaneous change to c-BN occurring evenly under pressure, they found that diamonds formed in clusters, and expanded. They also observed that the larger the number of layers of h-BN, the smaller the number of diamond clusters.

Riedo explained that the benefits of 2D BN diamonds over 2D carbon diamond (also known as diamene) are adaptability and potential economies of fabrication. "Recently we discovered that it is possible to induce diamene formation from graphene, however, specific types of substrates or chemicals are required, while h-BN can form diamonds on any substrate in ambient atmosphere. In general, it is really exciting the discovery of exceptional new properties in pressure-induced diamond phases in 2D materials" she said.

Riedo said the next phase will turn to applied research, with more large-scale experiments on mechanical resistance for specific applications.

Incidence rates of skin cancer (cutaneous malignant melanoma) have increased more than 550% in males and 250% in females since the early 1980s in England - according to a new study by Brighton and Sussex Medical School (BSMS).

Published in the new Lancet journal, The Lancet Regional Health - Europe, the study analysed data on more than 265,000 individuals diagnosed with skin cancer in England over the 38-year period, 1981-2018.

Skin cancer is the fifth most common cancer in the UK, with about 16,200 new cases each year.

Excessive exposure to UV radiation from the sun (or sunlight) is the main environmental risk factor for developing skin cancer. It is estimated that about 86% of all skin cancers in the UK are attributable to excessive exposure to sunlight. Exposure to artificial sources of UV radiation from indoor tanning beds/lamps is the second most important cause of skin cancer.

Professor Anjum Memon, Chair in Epidemiology and Public Health Medicine at BSMS and lead author of the study, said: "Our study shows that overall there has been a steady and significant increase in rates of skin cancer during the last four decades, which was essentially due to the continually increasing rates in middle (age 35-64 years) and old (65+ years) ages.

"We observed that the steepest increase was in males (more than two-fold that of females) and at old ages. The steeper increase in males is consistent with their relatively greater sun exposure and poor sun-protective behaviour."

Peter Bannister, medical student at BSMS and co-author of the study said: "The study also showed, for the first time, that the rates of skin cancer in young people (aged 0-34 years) in England have stabilised (or levelled off) during the last two decades. This finding suggests that public health campaigns targeted at children, adolescents and parents may be favourably influencing skin cancer incidence.

"The stabilisation of incidence in young people is encouraging and emphasises the importance of continued and sustained primary prevention measures to further improve sun-protective behaviours - such as avoidance of excessive exposure to sunlight and indoor tanning, appropriate clothing and application of sunscreens."

The site of skin cancer is most likely associated with the pattern of UV radiation exposure. Professor Memon said: "All the available evidence suggests that the enormous increase in the rates of skin cancer of the trunk (+817% in males, +613% in females) and arms (+750% in males, +518% in females) since the 1980s in England can be mostly attributable to an increasing trend in intermittent high intensity recreational UV radiation exposure due to lifestyle and societal changes."

"For example, (i) sunbathing, (ii) holidaying in a place with strong sunlight, (iii) proliferation of indoor tanning studios, budget holiday industry and airlines, (iv) increasing trend in travel to sunnier locations and (v) use of sunbeds."

Professor Malcolm Reed, Professor of Surgical Oncology and Dean of BSMS said: ""Considering that the large majority (86%) of skin cancers in the UK and other high-risk populations are preventable, this study has highlighted the potential benefits of effective primary and secondary prevention measures to substantially reduce the burden of the disease. This could have significant benefits for individuals, populations and health services, making skin cancer one of the most preventable forms of cancer on a global scale."

Researchers from North Carolina State University have created a trifunctional contraceptive gel that contains spermicidal, anti-viral and libido-enhancing agents in one formulation. When tested in a rat model, the gel both enhanced male libido and prevented pregnancy in 100% of cases, as compared to an average 87% effective rate with a commercially available contraceptive gel.

"We are using three pharmacological agents in a new formulation," says Ke Cheng, Randall B. Terry, Jr. Distinguished Professor in Regenerative Medicine at NC State's College of Veterinary Medicine, professor in the NC State/UNC Joint Department of Biomedical Engineering and corresponding author of a paper describing the work. "Our hope is that this trifunctional contraceptive gel could further enhance the safety and quality of sexual intercourse."

The new carbomer-based gel contains the contraceptive gossypol, the antiviral tenofovir and nitroglycerin to stimulate blood flow.

Cheng and his team first tested the gel in vitro to determine spermicidal and antiviral efficacy, as well as toxicity to vaginal epithelial cells. At 10 micrograms per milliliter gossypol concentration, the gel was effective in killing almost 100% of pig sperm - used for in vitro testing - in 30 seconds. Lower concentrations were equally effective by 180 seconds.

They also tested the gel in vitro against a lentivirus and found that it did have an inhibitory effect, indicating its potential to reduce transmission of sexually transmitted diseases. The gel was also shown not to be damaging to epithelial vaginal cells, as cell damage in treated cells was not significantly different from non-treated, or control cells.

Next, the researchers looked at contraceptive effects in a rat model. Eighteen female rats were divided into three groups: one that received the new gel; one that received a common commercially available contraceptive gel containing nonoxynol9; and a control. The females in the trifunctional gel group had no pregnancies, as opposed to one pregnancy in the nonoxynol9 group.

The team also tested the gel's effect on male rats' libido and erectile function. Rats that received the gel mated more frequently and with shorter incubation periods than those that did not.

"The trifunctional contraceptive gel we created yielded higher contraceptive success rates than those on the market," says Cheng, "and has great potential for improving the safety and quality of sexual intercourse."

The research appears in Bioactive Materials.

DISCOVERY BRIEF:

The first new skull of a rare species of the dinosaur Parasaurolophus (recognized by the large hollow tube that grows on its head) discovered in 97 years.

Exquisite preservation of the new skull gives paleontologists their first opportunity to definitively identify how such a bizarre structure grew on this dinosaur.

For the first time, this study found characteristics to link tube-crested dinosaur species found in southern North America (New Mexico, Utah), distinct from the only northern species (Alberta).

The locality, in northwestern New Mexico, is dated to about 75 million years ago, a time when North America was divided by a shallow sea and teemed with duckbilled dinosaurs, horned dinosaurs and early tyrannosaurs.

Fossils from the region are part of the natural heritage of the Diné (Navajo Nation) and Puebloan peoples. The new Parasaurolophus fossil, from Bureau of Land Management Wilderness lands in northwestern New Mexico, underscores the importance of protecting public lands as natural laboratories and repositories for scientific discoveries.

Jan. 25--DENVER--The first new skull discovered in nearly a century from a rare species of the iconic, tube-crested dinosaur Parasaurolophus was announced today in the journal PeerJ. The exquisite preservation of the skull, especially the bizarre tube-shaped nasal passage, finally revealed the structure of the crest after decades of disagreement.

Despite its extreme morphology, details of the specimen show that the crest is formed much like the crests of other, related duckbilled dinosaurs. Joe Sertich, curator of dinosaurs at the Denver Museum of Nature & Science and the leader of the team who discovered the specimen said, "This specimen is a wonderful example of amazing creatures evolving from a single ancestor."

"Imagine your nose growing up your face, three feet behind your head, then turning around to attach above your eyes. Parasaurolophus breathed through eight feet of pipe before oxygen ever reached its head," said Terry Gates, a paleontologist from North Carolina State University.

"Over the past 100 years, ideas for the purpose of the exaggerated tube crest have ranged from snorkels to super sniffers," noted David Evans, the Temerty Chair in Vertebrate Palaeontology and Vice President of Natural History at the Royal Ontario Museum. "But after decades of study, we now think these crests functioned primarily as sound resonators and visual displays used to communicate within their own species."

Among the most recognizable dinosaurs, the duckbilled Parasaurolophus sported an elongate, tube-like crest on its head containing an internal network of airways. Three species of Parasaurolophus are currently recognized, ranging from Alberta to New Mexico in rocks dating between 77 and 73.5 million years old. The new skull belongs to Parasaurolophus cyrtocristatus, previously known from a single specimen collected in the same region of New Mexico in 1923 by legendary fossil hunter Charles H. Sternberg. Both specimens display a shorter, more curved crest than other species, a feature that may be related to their immaturity at death.

The partial skull was discovered in 2017 by Smithsonian Ecology Fellow Erin Spear, Ph.D., while exploring the badlands of northwestern New Mexico as part of a Denver Museum of Nature & Science team. Located deep in the Bisti/De-Na-Zin Wilderness of New Mexico, only a tiny portion of the skull was visible on a steep sandstone slope. Museum volunteers led by Sertich were surprised to find the intact crest as they carefully chiseled the specimen from the sandstone. Abundant bone fragments at the site indicated that much of the skeleton may have once been preserved on an ancient sand bar, but only the partial skull, part of the lower jaw, and a handful of ribs survived erosion.

Today, the badlands of northwestern New Mexico are dry and sparsely vegetated, a dramatic contrast to the lush lowland floodplains preserved in their rocks. 75 million years ago, when Parasaurolophus lived in the region, North America was divided into two landmasses by a broad seaway. Laramidia, the ribbon of land to the west, extended from today's Alaska to central Mexico, hosting multiple episodes of mountain building in early stages of the construction of today's Rocky Mountains. These mountain-building events helped preserve diverse ecosystems of dinosaurs along their eastern flanks, some of the best-preserved and most continuous anywhere on Earth. Parasaurolophus shared lush, subtropical floodplains with other, crestless duckbilled dinosaurs, a diverse array of horned dinosaurs, and early tyrannosaurs alongside many emerging, modern groups of alligators, turtles and plants.

"The preservation of this new skull is spectacular, finally revealing in detail the bones that make up the crest of this amazing dinosaur known by nearly every dinosaur-obsessed kid," said Sertich. "This just reinforces the importance of protecting our public lands for scientific discoveries."

"My jaw dropped when I first saw the fossil," said Gates. He continued, "I've been waiting for nearly 20 years to see a specimen of this quality."

"This specimen is truly remarkable in its preservation," said Evans, who has also worked on this iconic dinosaur for almost two decades. "It has answered long-standing questions about how the crest is constructed and about the validity of this particular species. For me, this fossil is very exciting."

For decades, the family tree of Parasaurolophus placed the two long, straight-crested species of Parasaurolophus (P. walkeri from Alberta and P. tubicen from younger rocks in New Mexico) as most closely related despite being separated by more than 1,000 miles (1,600 km) and 2.5 million years. Analysis of additional features of the skull excluding the crest, together with information from other Parasaurolophus discoveries from southern Utah, suggest for the first time that all of the southern species from New Mexico and Utah may be more closely related than they are to their northern cousin. This fits patterns observed in other dinosaur groups of the same age, including horned dinosaurs.

Scientists have identified a key nutrient source used by algae living on melting ice surfaces linked to rising sea levels.
The Greenland ice sheet - the second largest ice body in the world after the Antarctic ice sheet - covers almost 80% of the surface of Greenland. Over the last 25 years, surface melting and water runoff from the ice sheet has increased by about 40%.
The international research team, led by the University of Leeds, analysed samples from the southwestern margin on Greenland's 1.7 million km² ice sheet over two years.
They discovered that phosphorus containing minerals may be driving ever-larger algal blooms on the Greenland Ice Sheet. As the algal blooms grow they darken the ice surface, decreasing albedo - the ability to reflect sunlight. The blooms cause increased melting thus contributing to higher sea levels. In particular, a band of low-albedo ice, known as the Dark Zone, has developed along the western margin of the massive ice sheet.

The research, published in Nature Communications, investigates the origin and impact of this phosphorus on algal blooms the Greenland Ice Sheet, improving understanding of how glacier ice algal blooms will contribute to future ice sheet melting.

By examining the surface dust, the scientists were able to demonstrate how phosphorus is used as a key nutrient to help the algae grow, identifying the phosphorus-bearing mineral hydroxylapatite as the source of fuel for the blooms in the Dark Zone. The hydroxylapatite was blown onto the ice from local rock outcrops.

Dr Jenine McCutcheon led the study while at Leeds' School of Earth and Environment, and is now an Assistant Professor at the University of Waterloo, Canada.

She said: "The photosynthesis rate of the ice algae improved significantly when we provided them with a source of phosphorus.

"Our mineralogy results revealed that the phosphorus used by ice algae may be coming from the hydroxylapatite we identified in the mineral dust.

"It's important to understand the controls on algal growth because of their role in ice sheet darkening.

"Although algal blooms can cover up to 78% of the bare ice surfaces in the Dark Zone, their abundance and size can vary greatly over time."

Dr McCutcheon added: "From one season to the next, algal blooms may change and vary in intensity, making them difficult to model year-to-year".

Associate Professor, Jim McQuaid at Leeds' School of Earth and Environment, is a co-author of the paper.

He said: "Mineral dust can be transported thousands of miles by wind, but the dust we examined was from local sources. As dryland areas in northerly latitudes become even drier under climate change, we can expect to see more dust transported and deposited on the Greenland Ice Sheet, further fuelling algal blooms.

"As atmospheric scientist, it's exciting to see how wind-blown mineral dust is linked to algal bloom development and impacts ice sheet melting."

Previous studies have shown that since 2000, the melt season in the Dark Zone has progressively started earlier and lasted longer, resulting in reduced ability for the ice sheet to reflect solar radiation.

Dr McCutcheon said: "The findings of this study will improve how we predict where algal blooms will happen in the future, and help us gain a better understanding of their role in ice sheet albedo reduction and enhanced melting."

Professor Liane G. Benning is the Leeds Principal Investigator of the £4 million Natural Environment Research Council project Black and Bloom, and is now at the German Research Centre for Geosciences in Potsdam, Germany.

She said: "The glacier ice algae bio-mine the phosphorus from the minerals fuelling the blooms that cover larger and larger areas each year, leading to more melting and faster rising sea levels.

"As current icesheet and climate models do not include this phenomena, this research will advance these models and give us a greater understanding of the annual lifecycle of algal blooms."

Depression, especially in urban areas, is on the rise, now more than ever. Mental health outcomes are influenced by, among other things, the type of environment where one lives. Former studies show that urban greenspace has a positive benefit on people experiencing mental ill health, but most of these studies used self-reported measures, which makes it difficult to compare the results and generalise conclusions on the effects of urban greenspace on mental health.

An interdisciplinary research team of UFZ, iDiv and Leipzig University tried to improve this issue by involving an objective indicator: prescriptions of antidepressants. To find out whether a specific type of 'everyday' green space - street trees dotting the neighbourhood sidewalks - could positively influence mental health, they focused on the questions, how the number and type of street trees and their proximity close to home correlated to the number of antidepressants prescribed.

The researchers analysed data from almost 10,000 Leipzig inhabitants, a mid-size city in Germany, who took part in the LIFE-Adult health study running at the University of Leipzig Medical Faculty. Combining that with data on the number and species type of street trees throughout the city of Leipzig, the researchers were able to identify the association between antidepressants prescriptions and the number of street trees at different distances from people's homes. Results were controlled for other factors known to be associated with depression, such as employment, gender, age, and body weight.

More trees immediately around the home (less than 100 meters) was associated with a reduced risk of being prescribed antidepressant medication. This association was especially strong for deprived groups. As these social groups are at the greatest risk for being prescribed antidepressants in Germany, street trees in cities can thereby serve as a nature-based solution for good mental health, the researchers write. At the same time, street trees may also help reduce the 'gap' in health inequality between economically different social groups. No association of tree types, however, and depression could be shown in this study.

"Our finding suggests that street trees - a small scale, publicly accessible form of urban greenspace - can help close the gap in health inequalities between economically different social groups," says lead author of the study Dr Melissa Marselle. "This is good news because street trees are relatively easy to achieve and their number can be increased without much planning effort." As an environmental psychologist, she conducted the research at UFZ and iDiv and is now based at the De Montford University of Leicester, UK. Marselle hopes that the research "should prompt local councils to plant street trees to urban areas as a way to improve mental health and reduce social inequalities. Street trees should be planted equally in residential areas to ensure those who are socially disadvantaged have equal access to receive its health benefits."

"Importantly, most planning guidance for urban greenspace is often based on purposeful visits for recreation", adds Dr Diana Bowler (iDiv, FSU, UFZ), data analyst in the team. "Our study shows that everyday nature close to home - the biodiversity you see out of the window or when walking or driving to work, school or shopping - is important for mental health." This finding is especially now in times of the COVID-19 lock-downs, Bowler adds.

And it's not only human health which could benefit. "We propose that adding street trees in residential urban areas is a nature-based solution that may not only promote mental health, but can also contribute to climate change mitigation and biodiversity conservation," says senior author Prof Aletta Bonn, who leads the department of ecosystem services at UFZ, iDiv and Friedrich-Schiller-University Jena. "To create these synergy effects, you don't even need large-scale expensive parks: more trees along the streets will do the trick. And that's a relatively inexpensive measure."

"This scientific contribution can be a foundation for city planners to save and, possibly, improve the life quality for inhabitants, in particular, in densely populated areas and in central city areas," adds Prof Toralf Kirsten from Leipzig University. "Therefore, this aspect should be taken into account when city areas are recreated and planned, despite high and increasing land cover costs. A healthy life of all living being is unaffordable."