Culture

WEST LAFAYETTE, Ind. -- It's not just to hide clutter anymore - add "saving the planet" to the reasons you leave the camera off during your next virtual meeting.

A new study says that despite a record drop in global carbon emissions in 2020, a pandemic-driven shift to remote work and more at-home entertainment still presents significant environmental impact due to how internet data is stored and transferred around the world.

Just one hour of videoconferencing or streaming, for example, emits 150-1,000 grams of carbon dioxide (a gallon of gasoline burned from a car emits about 8,887 grams), requires 2-12 liters of water and demands a land area adding up to about the size of an iPad Mini.

But leaving your camera off during a web call can reduce these footprints by 96%. Streaming content in standard definition rather than in high definition while using apps such as Netflix or Hulu also could bring an 86% reduction, the researchers estimated.

The study, conducted by researchers from Purdue University, Yale University and the Massachusetts Institute of Technology, is the first to analyze the water and land footprints associated with internet infrastructure in addition to carbon footprints. The findings are published in the journal Resources, Conservation & Recycling.

"If you just focus on one type of footprint, you miss out on others that can provide a more holistic look at environmental impact," said Roshanak "Roshi" Nateghi, a Purdue professor of industrial engineering, whose work looks to uncover gaps and assumptions in energy research that have led to underestimating the effects of climate change.

A number of countries have reported at least a 20% increase in internet traffic since March. If the trend continues through the end of 2021, this increased internet use alone would require a forest of about 71,600 square miles - twice the land area of Indiana - to sequester the emitted carbon, the study found.

The additional water needed in the processing and transmission of data would also be enough to fill more than 300,000 Olympic-size swimming pools, while the resulting land footprint would be about equal to the size of Los Angeles.

The team estimated the carbon, water and land footprints associated with each gigabyte of data used in YouTube, Zoom, Facebook, Instagram, Twitter, TikTok and 12 other platforms, as well as in online gaming and miscellaneous web surfing. As expected, the more video used in an application, the larger the footprints.

Because data processing uses a lot of electricity, and any production of electricity has carbon, water and land footprints, reducing data download reduces environmental damage.

"Banking systems tell you the positive environmental impact of going paperless, but no one tells you the benefit of turning off your camera or reducing your streaming quality. So without your consent, these platforms are increasing your environmental footprint," said Kaveh Madani, who led and directed this study as a visiting fellow at the Yale MacMillan Center.

The internet's carbon footprint had already been increasing before COVID-19 lockdowns, accounting for about 3.7% of global greenhouse gas emissions. But the water and land footprints of internet infrastructure have largely been overlooked in studies of how internet use impacts the environment, Madani said.

Madani teamed up with Nateghi's research group to investigate these footprints and how they might be affected by increased internet traffic, finding that the footprints not only vary by web platform, but also by the country. The team gathered data for Brazil, China, France, Germany, India, Iran, Japan, Mexico, Pakistan, Russia, South Africa, the U.K. and the U.S.

Processing and transmitting internet data in the U.S., the researchers found, has a carbon footprint that is 9% higher than the world median, but water and land footprints that are 45% and 58% lower, respectively.

Incorporating the water and land footprints of internet infrastructure painted a surprising picture for a few countries. Even though Germany, a world renewable energy leader, has a carbon footprint well below the world median, its water and land footprints are much higher. The country's energy production land footprint, for example, is 204% above the median, the researchers calculated.

Purdue graduate students Renee Obringer, Benjamin Rachunok and Debora Maia-Silva performed the calculations and data analysis in collaboration with Maryam Arbabzadeh, a postdoctoral research associate at MIT. The estimates are based on publicly available data for each platform and country, models developed by Madani's research group and known values of energy use per gigabyte of fixed-line internet use.

The estimates are rough, the researchers say, since they're only as good as the data made available by service providers and third parties. But the team believes that the estimates still help to document a trend and bring a more comprehensive understanding of environmental footprints associated with internet use.

"These are the best estimates given the available data. In view of these reported surges, there is a hope now for higher transparency to guide policy," Nateghi said.

January 14, 2021 - Orthopaedic surgeons have traditionally been taught that certain types of knee symptoms indicate damage to specialized structures called the menisci. But these "meniscal" and "mechanical" symptoms do not reflect what surgeons will find at knee arthroscopy, reports a study in The Journal of Bone & Joint Surgery. The journal is published in the Lippincott portfolio in partnership with Wolters Kluwer.

Both types of symptoms are strongly related to the overall amount of cartilage damage in the knee joint - but not to the presence of meniscal tears, according to the new research by Elizabeth G. Matzkin, MD, and colleagues of Harvard Medical School. They write, "Our study adds strong evidence to refute the current dogma that meniscal pathology is the primary driver of traditionally defined 'meniscal' and 'mechanical' knee symptoms."

New evidence 'questions diagnostic utility' of knee symptoms
Sometimes called the "shock absorbers" of the knee, the menisci are a pair of horseshoe-shaped pieces of cartilage that help to cushion the knee joint. Among orthopaedic surgeons, conventional wisdom is that "mechanical" symptoms like knee locking or catching are caused by meniscal tears, which can be treated with an arthroscopic surgical procedure. However, a growing body of evidence suggests that other types of injuries can also cause these types of knee symptoms.

Other recent studies have suggested that "meniscal" symptoms like knee grinding, popping, or clicking are better indicators of meniscal tears. Dr. Matzkin and colleagues questioned whether either of these two types of symptoms are truly indicators of meniscus tear within the knee joint - and whether they are of value in surgical decision-making.

The researchers analyzed the relationship between these knee symptoms and the findings of knee arthroscopy in 565 patients. All patients underwent knee arthroscopy performed by Dr. Matzkin between 2012 and 2019. The goal was to determine whether "mechanical" or "meniscal" symptoms were related to the presence of meniscal tears, cartilage damage, or other types of joint disease identified via arthroscopy.

The most frequently reported symptoms included worse pain with knee pivoting/twisting (85 percent), knee grinding (74 percent), and knee catching (63 percent). Arthroscopy revealed unstable meniscal tears in 12 percent of patients, stable tears in 66 percent, and no tear in 21 percent.

Meniscal tear patterns and meniscal damage were found to be unrelated to individual symptoms of knee grinding or pain with pivoting.

In contrast, the overall severity of cartilage damage was significantly associated with knee symptoms - especially catching and grinding. Knee catching was present in 49 percent of patients with no cartilage damage versus 78 percent of those with damage in all three compartments of the knee.

Because meniscal tears and cartilage damage often occur together, the study suggests that structural cartilage damage is the "primary driver" of knee symptoms. "Our data align with the observation that cartilage damage and meniscal tears are both manifestations of overall degenerative knee disease," Dr. Matzkin and coauthors write.

The findings "further question the diagnostic utility" of mechanical and meniscal symptoms and their use "as the indications for knee arthroscopy," the researchers add. Dr. Matzkin and colleagues believe that future studies should avoid these misleading terms, and instead use specific descriptors of knee symptoms. The researchers plan further studies to assess how specific types of symptoms are related to outcomes after arthroscopic surgery.

Click here to read "Meniscal and Mechanical Symptoms Are Associated with Cartilage Damage, Not Meniscal Pathology."
DOI: 10.2106/JBJS.20.01193

In today's economy, American businesses often tap into professional management to grow, but most firms in India and other developing countries are family owned and often shun outside managers. A new study co-authored by Yale economist Michael Peters explores the effects that the absence of outside professional management has on India's businesses and the country's economy.

The study, published in the American Economic Review, uses a novel model to compare the relationship between the efficiency of outside managers and firm growth in the United States and India. It shows that the lack of managerial delegation factors significantly into why businesses in India tend to stay small and has wider implications on the country's economy, constraining innovation, economic growth, and per capita income.

"There's been growing evidence that managerial services might be the key missing input for many firms in poor countries," said Peters, associate professor of economics in Yale's Faculty of Arts and Sciences. "Our analysis confirms that the absence of managerial delegation is a significant factor in why successful Indian businesses fail to grow, which reduces the overall productivity of the country's economy."

By growing, companies generate employment, promote innovation, and contribute to a countries' economic productivity, the researchers say.

In developed countries, family-owned firms such as Walmart, Ford Motor Co., and the Lego Group, which all emerged from humble beginnings, grew into corporate behemoths, with hundreds of thousands of employees, by delegating key operations to outside managers. But businesses in developing countries rarely hire managers outside the owners' families, the researchers note.

Peters and his co-authors, Ufuk Akcigit of the University of Chicago and Harun Alp of the University of Pennsylvania, focused their analysis on this disparity between developed and developing countries' firm sizes. They created a quantitative model that centers the role of managerial delegation in firm growth. It incorporated plant-level data from the United States and India and was calibrated to recognize that business in India might face higher barriers to growth, such as having less access to start-up capital, than U.S. businesses.

In India, more than 9 out of 10 of manufacturing businesses have fewer than four employees, and those small firms account for more than half of total employment. In contrast, two-thirds of U.S. manufacturing employment is concentrated in establishments with at least 100 employees, and only one-third of firms have fewer than four employees, according to the study.

The researchers found that India's economy suffers from "a lack of selection" -- the process of creative destruction through which successful businesses expand while unproductive firms close or are swallowed up by competitors -- allowing unproductive businesses to survive because successful businesses do not expand. Their analysis showed that the low productivity of outside managers in India, which they estimate to be substantially lower than in the United States, is one cause of the lack of selection and has negative consequences for India's economy.

If Indian businesses used outside managers as efficiently as U.S. businesses, it would boost economic productivity in India and increase the country's per capita income by about 11%, according to the study.

The study found a strong complementary relationship between the quality of outside managers and other factors affecting firm growth, such as access to capital or credit. Increasing the efficiency of managerial delegation to U.S. standards would increase average firm size by 3%, the researchers said. In contrast, if U.S. businesses had to operate with management practices common in India, the country's average firm would shrink by about 15%. This disparity between the U.S. and India shows that the productivity of outside managers is not the only determinant of firm growth and that other forces prevent successful Indian businesses from expanding, Peters explained.

"The complementarity between the efficiency of delegating managerial tasks and other aspects affecting firm growth, such as access to credit, is one of our key results," said Peters, who is affiliated with Yale's Economic Growth Center. "For improvements to managerial quality to have a large effect, other factors hindering growth must be addressed. If you repair a punctured tire, you still can't drive if your other tires are flat."

Genome analysis can provide information on genes and their location on a strand of DNA, but such analysis reveals little about their spatial location in relation to one another within chromosomes -- the highly complex, three-dimensional structures that hold genetic information.

Chromosomes resemble a fuzzy "X" in microscopy images and can carry thousands of genes. They are formed when DNA winds around proteins -- called histones -- which are further folded into complexes called chromatin, which make up individual chromosomes.

Knowing which genes are located in spatial proximity within the chromatin is important because genes that are near each other generally work together.

Now, researchers at the University of Illinois Chicago report on a computational technique that uses heat map data to reverse engineer highly detailed models of chromosomes. Through this work, the researchers have uncovered new information about the close spatial relationships that chromatin folding creates between genes that can be highly distant from one another along DNA strands.

Their findings are published in the journal Nature Communications.

"Folding of the chromatin brings genes that are far away from each other into close proximity. If we know that certain groups of genes are spatial neighbors because of this folding, that tells us they most likely work together to drive processes such as the development of immunity, or even more fundamental processes like development or cell differentiation," said Jie Liang, UIC Richard and Loan Hill Professor of Bioengineering and a corresponding author on the paper. "This is important for better understanding these processes or development of new therapeutics to prevent or treat cancer and other diseases."

Liang and his colleagues developed a way to reverse engineer the complex structures of individual chromosomes using information from a process called Hi-C. Hi-C generates heat maps based on probabilities reflecting which genes are most likely to be spatially close to one another. These heat maps can provide approximate three-dimensional information on how chromosomes are organized, but because they are based on genetic material from multiple cells, the maps represent average likelihoods of proximity between genes, not exact locations.

Liang and colleagues looked at Hi-C heat maps of chromosomes from cells of fruit fly embryos, which have only eight chromosomes. They used these heat maps together with new advanced computational methods to generate extremely detailed three-dimensional maps of the chromosomes of individual cells.

"For the first time, we are able to produce single-cell models that accurately represent genetic spatial relationships within chromosomes," Liang said. "With these models, we can uncover rich biological patterns and answer basic biological questions about three-dimensional structural changes chromosomes undergo to cause stem cells to develop into different tissues, and how malfunctions in these processes lead to diseases such as cancer."

Computational materials science experts at the U.S. Department of Energy's Ames Laboratory enhanced an algorithm that borrows its approach from the nesting habits of cuckoo birds, reducing the search time for new high-tech alloys from weeks to mere seconds.

The scientists are investigating a type of alloys called high-entropy alloys, a novel class of materials that are highly sought after for a host of unusual and potentially beneficial properties. They are lightweight in relation to their strength, fracture-resistant, highly corrosion and oxidation resistant, and stand up well in high-temperature and high-pressure environments -- making them attractive materials for aerospace industry, space exploration, nuclear energy, and defense applications.

While the promise of these materials is great, they present major difficulties to scientists attempting to search for and customize them for use in technologies. Because these alloys are constructed of five or more different elements, they are expensive and difficult to develop and search experimentally, making an Edison-like approach a nonstarter. With so many ingredients, and so many different ways to construct them, there are nearly endless permutations of recipes for their design. Among literally billions of options, how do researchers narrow their search to a few excellent potential candidates for an application?

The answer in this case is an evolutionary algorithm, using a hybrid version of a computer program developed ten years ago, called Cuckoo Search (CS). Cuckoo birds are brood parasites, laying their eggs in the nest of a host bird such that they end up rearing the bigger, stronger cuckoo chick as one of its own.

"This 'survival of the fittest' strategy from the behavior of birds is the idea behind Cuckoo Search," said Duane Johnson, a computational materials scientist at Ames Laboratory. Each egg represents a possible solution, competing to be the best solution in any given nest in a fixed number of possible nests. The best solution of each nest competes against other nests, until the best solution is found.

The Ames Laboratory team put a twist on the Cuckoo Search, which greatly speeded up the process of locating ideal alloys or the best "egg" within a huge number of possibilities. The original CS takes advantage of a mathematical concept called Lévy flight, which computational theorists use to their advantage in searching extremely large data sets. But, while this method works for large data sets, the Ames Lab team found that pairing another mathematical concept, a Monte Carlo algorithm, with Lévy flight, greatly reduced the time to achieving optimal candidates for high-entropy alloys, providing optimal models almost on the fly.

"With the model-building bottleneck eliminated, computational design can be performed that is currently impractical, said Johnson, "As our hybrid CS is problem-agnostic, it offers application in optimization in many diverse fields."

Researchers from the PTSD Systems Biology Consortium, led by scientists from the Walter Reed Army Institute of Research, have identified distinct biotypes for post-traumatic stress disorder, the first of their kind for any psychological disorder. "These biotypes can refine the development of screening tools and may explain the varying efficacy of PTSD treatments", said Dr. Marti Jett, leader of the consortium and WRAIR chief scientist.

Publishing their work in Molecular Psychiatry in a manuscript first authored by WRAIR's Dr. Ruoting Yang, researchers used blood tests from male, combat-exposed veterans across a three year period to identify two PTSD biotypes, G1--characterized by mild, inherent co-morbidities typical of PTSD--and G2--which includes more severe symptoms typical of PTSD and report more physical distress--with differing genetic markers and underlying mechanisms of disease. Building on previously published work using machine learning, led by Dr. Francis J. Doyle III, dean of Harvard University's School of Engineering and Applied Sciences and computational lead of the PTSD Systems Biology Consortium, findings were expanded and validated with two additional veteran cohorts and an active-duty cohort.

PTSD diagnosis has long been complicated by a reliance on self-reporting of patient symptoms, particularly the underreporting of signs of distress due to perceived stigma. "These findings help overcome that gap, using data that link objective molecular and physiological measures with PTSD biotypes as a screening tool for early indicators of distress and to avert full, chronic PTSD," explained Dr. Charles Marmar, chair of New York University Langone Health's Department of Psychiatry and clinical lead of the PTSD Systems Biology Consortium.

Additionally, one PTSD medication is currently FDA-approved for use in military personnel and is thought to be approximately 50% effective; clinical trials for other medications are further limited in efficacy. "These data set the stage for physicians to link treatments to specific biotypes, providing a blueprint for targeted therapeutics and better patient outcomes," said Dr. Kerry Ressler, consortium member and chief scientific officer of McLean Hospital.

Researchers with the PTSD Systems Biology Consortium, a network of government and academic laboratories, plan to continue their research to further identify and validate PTSD biotypes to develop better screening tools, including a test to biotype military personnel with probable PTSD symptoms in field settings away from clinicians. Additionally, future studies are planned to incorporate biotyping into clinical trials for PTSD therapeutics currently in development.

TROY, N.Y. -- As cancer and tumor cells move inside the human body, they impart and are subject to mechanical forces. In order to understand how these actions affect cancer cell growth, spread, and invasion, a team of engineers at Rensselaer Polytechnic Institute is developing new models that mimic aspects of the mechanical environment within the body, providing new insight into how and why tumors develop in certain ways.

In research published today in Integrative Biology, a team of engineers from Rensselaer developed an in vitro -- in the lab -- lymphatic vessel model to study the growth of tumor emboli, collections of tumor cells within vessels that are often associated with increased metastasis and tumor recurrence.

"The growth of tumor emboli is important for the spread and metastasis of certain types of cancers. For example, inflammatory breast cancer has this growth pattern of just massive spread of emboli growing within dermal lymphatic vessels, in the breast, and it's very aggressive in that way," said Kristen Mills, an assistant professor of mechanical engineering at Rensselaer, who led this research. "This growth of tumor emboli hasn't really been studied very much."

Previous tumor models in the lab have used unconstrained spheroids of tumor cells that don't allow researchers to study the mechanical interactions that truly happen within the physical boundaries of a tubular-shaped vessel. To more closely mimic what happens in the body, Mills and her team modeled a lymphatic vessel in the lab using a small channel in a gel. They placed these channels within either stiff or soft bioinert gel, in order to mimic the constraints that tumor emboli may encounter in stiff, diseased tissue, or soft, healthy tissue.

To incorporate the varying growth behaviors of cells, the team used breast and colon cancer cell aggregates to model the emboli, one which is more aggressive, the other less.

Researchers found that the model of a stiff tumor environment constrained both types of tumor emboli to the cylindrical channel, causing rapid growth of the emboli along the vessel. But, they found that the growth of the cancer cells was different, based on their type, in the softer matrix model, which mimics healthy colon or breast tissue.

The aggressive cells were not affected by the presence of the open channel at all and grew as a sphere, bulging into the matrix, while the less aggressive cells first grew along the channel for several days before bulging into the matrix. The researchers linked the differences in growth to the force generation capability of the cancer cells. Independent measurements indicated that the aggressive cancer cells were capable of exerting significantly more force than the less aggressive cells.

Growth along a vessel or channel is problematic, Mills said, because the cells within the tumor have constant access to life-sustaining nutrients through the vessel wall. When the tumor cells grow in a sphere and begin to bulge, Mills said, the cells in the center of that mass get farther and farther away from nutrients until they are cut off and eventually die. This information could be critical for therapeutic design and prescription.

"We think this is important because it somehow suggests that, if the tumor tissue surrounding these vessels has been abnormally stiffened through disease, or if -- for example -- the breast tissue is already denser or stiffer, you might really see much more growth within the vessels than with a softer tissue," said Mills, who is also a member of the Center for Biotechnology and Interdisciplinary Studies (CBIS) at Rensselaer.

Jonathan Kulwatno, a graduate student in biomedical engineering at Rensselaer, was first author on this paper. Mills and Kulwatno collaborated with researchers from Mount Sinai.

This unique, mechanical engineering approach to studying cancer is a hallmark of the transformative work being done within CBIS, where researchers like Mills can collaborate across disciplines with other engineers and scientists working in similar areas.

"Professor Mills' engineering approach to studying cancer is laying a critical foundation, where interdisciplinary approaches are used to understand the mechanobiology of cancer with an eventual therapeutic goal," said Deepak Vashishth, the director of CBIS.

As Mills and her team continue their research, she said, they look for new ways to make these models more complex without losing the ability to isolate critical mechanical mechanisms.

GAINESVILLE, Fla. --- Scientists have found a new species of fleshy verdigris lichen, thanks to DNA analysis of museum specimens. Misidentified by its original collectors, the lichen is only known from 32 specimens collected in North and Central Florida scrubland between 1885 and 1985. Now the hunt is on to find it in the wild - if it still exists.

The lichen, named Cora timucua in honor of Florida's Timucua people, is critically endangered, even more so than the federally protected Florida perforate reindeer lichen, and possibly extinct. Researchers are holding out hope that C. timucua may persist in undisturbed pockets of the state's dwindling pine scrub habitat, though recent searches came up empty.

"The million-dollar question is 'Where is this lichen?'" said Laurel Kaminsky, a digitization manager at the Florida Museum of Natural History and co-author of the study. "The optimist in me says it's still out there."

Kaminsky said the sparse information recorded by the lichen's collectors makes it difficult to retrace their steps. More widespread in the early 20th century, C. timucua was collected only from the Ocala National Forest and O'Leno State Park after 1968, two of Florida's last remaining scrub ecosystems. Citrus groves and urban developments have replaced up to 90% of the state's sand pine scrub.

"If it's anywhere, it's going to take a lot of looking in very specific habitats to find it," Kaminsky said.

Affectionately dubbed "Timucua heart lichen," the new species resembles a shelf fungus and is about the size of a sand dollar with scalloped edges. It can be distinguished from wood-rotting fungi by its texture: felty and papery, with curved lobes and a cracked underside.

But its color is an enigma. The lichen is light gray when dry, but specimens turn a deep blue-green and bleed a reddish-brown pigment when wet in a laboratory setting. Without photos and detailed descriptions of the lichen in nature, scientists don't yet know how it reacts to moisture in the wild.

"In general, people take nature for granted, and the Timucua heart lichen story might tell us sometimes we are too late," said Manuela Dal Forno, senior author of the study and a lichenologist at the Botanical Research Institute of Texas. "Right now, we need everybody's help in trying to locate this lichen in Florida."

Kaminsky said Timucua heart lichen likely prefers old-growth pine scrub habitat, which has taller trees and established populations of native Florida plants, such as rusty lyonia, a shrub characterized by reddish fibers lining its leaves. But hikers should avoid collecting any potential specimens they find: Instead, they can photograph the lichen and upload images to the Timucua Heart Lichen Project on the community science platform iNaturalist for identification.

Florida's hidden lichen life

Lichens are partnerships between fungi and photosynthesizing organisms and play a key role in their ecosystems by enriching soils and cycling nutrients. But much of the world's lichen diversity remains hidden. A chronic shortage of lichen experts led to the delay in Timucua heart lichen's discovery, Kaminsky said. She added that Florida could harbor as many as 1,000 lichen species, many of which remain undescribed and whose populations could also be imperiled.

A previous survey of South Florida's Fackahatchee Strand Preserve led by Robert Lücking, a curator at Berlin's Botanical Garden and Botanical Museum and lead author of the C. timucua study, found more than 400 lichen species in about 250 acres. Of the 400 species, 18 were new to science and 100 had yet to be recorded in North America.

"This emphasizes how little we know about lichen diversity and their genetic information, as well as the importance of digitization projects," said Dal Forno, also a research associate at the Smithsonian's National Museum of Natural History. "There are so many lichens out there, but not enough lichenologists to study them."

Timucua heart lichen belongs to the genus Cora, a group of nearly 200 tropical lichens - once thought to be a single species - typically found in mountain habitats. Its discovery in Florida is the northernmost record of a Cora species, and the new species is the sole representative of its genus in the U.S.

Even if the species is extinct, studying its DNA could help scientists understand how the species arrived in Florida. Timucua heart lichen's closest known relatives are in Colombia and Brazil, raising questions about how C. timucua was able to grow in a habitat so different from its sister species, Dal Forno said.

Digital museum specimens led to discovery

Increasingly, researchers need not pack a tent and head into the field to find new species. Instead, they can search online databases of specimen data from museums around the world. In 2012, a National Science Foundation grant helped scientists digitize lichens from the Florida Museum's fungal herbarium, uploading basic specimen information and images to two international data networks, the Global Biodiversity Information Facility and the Consortium of North American Lichen Herbaria.

It was on the web that Lücking and Gary Perlmutter, acting curator of lichens at the University of North Carolina at Chapel Hill herbarium and a study co-author, spotted clusters of Florida Cora specimens, far outside the genus's known range. They contacted Kaminsky, suspecting DNA analysis would uncover misidentified specimens.

"I knew we had these specimens, but I just thought everybody else knew," Kaminsky said. "The digitization just opened it up for other people to find it and do cool things with it."

Climate change impacts, affecting primarily ecosystems' functions and consequently human sectors, have become a crucial topic. Observed and expected variations in climate conditions can in fact undermine the ecosystems' ecological equilibrium: average climate patterns, mainly represented by intra-annual (monthly to seasonal) temperature and precipitation cycle, directly influence the distribution, abundance and interactions of biological species.

During the long history of scientific research on the relationships between climate and Earth's communities, numerous meteorological variables and/or derived indices have been formulated, calculated and applied to explain the geographic distribution of natural populations along climate gradients, characterized by intra-annual patterns of temperature and precipitation. Such variables and indices are also known as bioclimatic indicators (BioClimInd). They mainly result from primary - observed or modelled - climate fields (e.g. minimum, maximum and mean temperature, precipitation amount) and contribute to delineate the bioclimatic "envelope" for species in terms of favourable environmental conditions, also referred to as "suitability.

A study led by the CMCC Foundation and recently published on the Nature Journal Scientific Data released a new global and free access dataset of bioclimatic indicators at 0.5° by 0.5° spatial resolution (ca. 50 km at the equator) for historical and future conditions. "Our target was to widen the availability of bioclimatic information by an ensemble of bioclimatic indicators valuable both for historical and future robust climate change impacts' assessments", explains Sergio Noce, CMCC scientist and lead author of the study. His research at CMCC focuses on the analysis of the potential impacts of climate change on spatial distribution of forest species. "We're thinking about a wide range of research fields such as wildlife ecology, natural resources' conservation and management, botanic, forestry and many other fields involving biogeography. More in general, our data could be useful for all studies using species distribution modelling. Considering its spatial resolution, this dataset will be especially suitable for studies at continental - global scale, for example, to study regions such as the Mediterranean or the Russian territory; even before releasing the dataset, our team published a work on the impacts of global warming on Russian forests from a biogeographical perspective using these bioclimatic indicators".

What is meant by biogeography and why bioclimatic indicators are so important? As he explained in his Nature Behind the paper article, "Biogeography studies the distribution of species and ecosystems in a geographic space and the relationships between these communities and, among others, the climatic conditions: bioclimatic indicators summarize these conditions. Changes in species distribution has always occurred; there are many examples of animal or plant species that 'migrated' towards more suitable environmental and climatic conditions in the past. To make an example, starting from the end of the most recent glaciation (approx 11-12,000 years B.P.) the European hazel were only in some glacial refugia in southern Europe; as climate was getting warmer, hazel started to migrate north and spread in all the European continent. Climate change accelerated this processes and today understanding and being able to forecast future climate envelopes, that is understanding how species distribution and occurrence will change in the future, is becoming always more important."

The new dataset, called CMCC-BioClimInd, will contribute to achieve this goal while providing a set of 35 bioclimatic indices calculated both for a 40-years historical interval (1960-1999) and for two future time horizons (mid-term 2040-2079 and long-term 2060-2099) from, respectively, post-processing of climate reanalysis and an ensemble of 11 Coupled Model Intercomparison Project Phase 5 (CMIP5) bias corrected climate simulations.

Therefore the new CMCC dataset of bioclimatic indicators will be useful to a broad community of researchers aiming at reproducing and modelling, respectively, current and future habitats' ranges by mean of a Species Distribution Modelling (SDM) approach, where large amount of high quality and up-to-date environmental (especially climate) data is required.

"On the one hand", Noce concludes, "the exploitation of indicators instead of just raw climate variables enables easier inferring of relationships between the studied topic (species occurrence, resources availability etc.) and the climate regime to support decision for complex systems; on the other hand, using the ensemble allows considering the variability across simulations due to the different models' physics and the uncertain future development pathways."

The work is ongoing and in the near future, CMCC researchers wish to keep CMCC-BioClimInd up-to-date adding more climate simulations and/or further model outputs.

The data of individual indicators are publicly available for download in the commonly used Network Common Data Form 4 (NetCDF4) format in CMCC Data Delivery System (CMCC DDS) just released online, a unique, consistent and seamless access point for all data produced and used by CMCC.

BIRMINGHAM, Ala. - Use of the diabetes drug metformin -- before a diagnosis of COVID-19 -- is associated with a threefold decrease in mortality in COVID-19 patients with Type 2 diabetes, according to a racially diverse study at the University of Alabama at Birmingham. Diabetes is a significant comorbidity for COVID-19.

"This beneficial effect remained, even after correcting for age, sex, race, obesity, and hypertension or chronic kidney disease and heart failure," said Anath Shalev, M.D., director of UAB's Comprehensive Diabetes Center and leader of the study.

"Since similar results have now been obtained in different populations from around the world -- including China, France and a UnitedHealthcare analysis -- this suggests that the observed reduction in mortality risk associated with metformin use in subjects with Type 2 diabetes and COVID-19 might be generalizable," Shalev said.

How metformin improves prognosis in the context of COVID-19 is not known, Shalev says. The UAB findings suggest that the mechanisms may go beyond any expected improvement in glycemic control or obesity, since neither body mass index, blood glucose nor hemoglobin A1C were lower in the metformin users who survived as compared to those who died.

"The mechanisms may involve metformin's previously described anti-inflammatory and anti-thrombotic effects," Shalev said.

The study -- first made available in MedRxiv and now published in the peer-reviewed journal Frontiers in Endocrinology -- included 25,326 patients tested for COVID-19 at the tertiary care UAB Hospital between Feb. 25 and June 22 of last year. Of the 604 patients found to be COVID-19-positive, 311 were African Americans.

The primary outcome in the study was mortality in COVID-19-positive subjects, and the potential association with subject characteristics or comorbidities was analyzed.

Researchers found that Blacks, who are only 26 percent of Alabama's population, were 52 percent of those who tested positive for COVID-19, and only 30 percent of those who tested negative. In contrast, only 36 percent of the COVID-19-positive subjects were white, while whites made up 56 percent of those who tested negative, further underlining the racial disparity. Once COVID-19-positive though, no significant racial difference in mortality was observed.

"In our cohort," Shalev said, "being African American appeared to be primarily a risk factor for contracting COVID-19, rather than for mortality. This suggests that any racial disparity observed is likely due to exposure risk and external socioeconomic factors, including access to proper health care."

Overall mortality for COVID-19-positive patients was 11 percent. The study found that 93 percent of deaths occurred in subjects over the age of 50, and being male or having high blood pressure was associated with a significantly elevated risk of death. Diabetes was associated with a dramatic increase in mortality, with an odds ratio of 3.62. Overall, 67 percent of deaths in the study occurred in subjects with diabetes.

The researchers looked at the effects of diabetes treatment on adverse COVID-19 outcomes, focusing on insulin and metformin as the two most common medications for Type 2 diabetes. They found that prior insulin use did not affect mortality risk.

However, prior metformin use was a different matter. Metformin use significantly reduced the odds of dying, and the 11 percent mortality for metformin users was not only comparable to that of the general COVID-19-positive population, it was dramatically lower than the 23 percent mortality for diabetes patients not on metformin.

After controlling for other covariates, age, sex and metformin use emerged as independent factors affecting COVID-19-related mortality. Interestingly, even after controlling for all these other covariates, death was significantly less likely -- with an odds ratio of 0.33 -- for Type 2 diabetes subjects taking metformin, compared with those who did not take metformin.

"These results suggest that, while diabetes is an independent risk factor for COVID-19-related mortality," Shalev said, "this risk is dramatically reduced in subjects taking metformin -- raising the possibility that metformin may provide a protective approach in this high-risk population."

The researchers say future studies will need to explore how metformin is protective, as well as assess the risks and benefits of metformin treatment and the indications for its use in the face of the ongoing COVID-19 pandemic.

Ignoring a colleague's greeting or making a sarcastic comment in the workplace may actually do more harm than intended, according to West Virginia University research.

Perceived low-grade forms of workplace mistreatment, such as avoiding eye contact or excluding a coworker from conversation, can amplify suicidal thoughts in employees with mood disorders, based on a study by Kayla Follmer, assistant professor of management, and Jake Follmer, assistant professor of educational psychology.

"We know from prior research that minor forms of workplace mistreatment reduce employee engagement," Kayla Follmer said. "But our paper provided an explanation for why this was occurring. Mistreatment increases suicidal ideation (thoughts) and because of that, work engagement is reduced."

The research team surveyed 279 American adults who are employed 20 or more hours a week and diagnosed with depression or bipolar disorder.

"What we wanted to do was hone in on employees most likely to experience these effects because that gives us greater opportunity for intervention," she said.

The researchers then asked participants to rate various experiences relating to workplace mistreatment, suicidal ideation, and job engagement over several months.

Kayla Follmer believes this is the first study that links these types of workplace mistreatments to potentially serious psychological outcomes. Their findings are published in Organizational Behavior and Human Decision Processes.

"These actions are not egregious or illegal," she said. "It's not even considered bullying or harassment. These are ways, on a day-to-day basis, that you might hurt somebody but in a low-grade way. It's how we may behave and we don't think twice about it."

Another finding from the study suggests that these effects are stronger for those not receiving treatment for their depression or mood disorder. Kayla Follmer estimated that roughly 50 percent of participants fit into that category.

Mental health in the workplace is one of her areas of expertise. A trained industrial organizational psychologist, she considers the topic overlooked in management research and the business world, in general.

"We all focus on bottom lines and productivity but we fail to take into account employee experiences and the effect mental illness can have on those experiences," she said.

In turn, organizations can enhance the workplace environment by providing mental health resources to employees, which may increase production and job satisfaction.

While research for this study was conducted before the COVID-19 pandemic, Kayla Follmer wonders if the world of remote work intensifies the effects of mental health and workplace engagement.

She theorized that employees no longer working in a traditional office setting because of the pandemic may feel less engaged.

And virtual communication can be easily misconstrued, adding a layer of instability.

"In some ways, our results may be even more important now because we know that depression and anxiety are at the highest levels they've been," she said.

"Suicide and depression are very taboo, dark topics. It can be heavy at times to research, but that's the responsibility we bear to bring these experiences into awareness for organizations and to tell them we can do better. And it's our responsibility to do better for those individuals who need us."

A team of biophysicists from the University of Massachusetts Amherst and Penn State College of Medicine set out to tackle the long-standing question about the nature of force generation by myosin, the molecular motor responsible for muscle contraction and many other cellular processes. The key question they addressed - one of the most controversial topics in the field - was: how does myosin convert chemical energy, in the form of ATP, into mechanical work?

The answer revealed new details into how myosin, the engine of muscle and related motor proteins, transduces energy.

In the end, their unprecedented research, meticulously repeated with different controls and double-checked, supported their hypothesis that the mechanical events of a molecular motor precede - rather than follow - the biochemical events, directly challenging the long-held view that biochemical events gate the force-generating event. The work, published in the Journal of Biological Chemistry, was selected as an Editor's Pick for "providing an exceptional contribution to the field."

Completing complementary experiments to examine myosin at the most minute level, the scientists used a combination of technologies - single molecule laser trapping at UMass Amherst and FRET (fluorescence resonance energy transfer) at Penn State and the University of Minnesota. The team was led by muscle biophysicist Edward "Ned" Debold, associate professor in the UMass Amherst School of Public Health and Health Sciences; biochemist Christopher Yengo, professor at Penn State College of Medicine; and muscle biophysicist David Thomas, professor in the College of Biological Sciences at the University of Minnesota.

"This was the first time these two cutting-edge techniques have been combined together to study a molecular motor and answer an age-old question," Debold says. "We've known for 50 years the broad scope of how things like muscle and molecular motors work, but we didn't know the details of how that occurs at the most minute level, the nanoscale motions. It's like we're looking under the hood of a car and examining how the engine works. How does it take the fuel and convert it into work when you press the gas pedal?"

Using his single molecule laser trap assay in his lab, Debold and his team, including graduate students Brent Scott and Chris Marang, were able to directly observe the size and rate of myosin's nanoscale mechanical motions as it interacted with a single actin filament, its molecular partner in force generation. They observed that the force-generating step, or powerstroke, happened extremely fast, almost as soon as it bound to the actin filament.

In parallel experiments using FRET assays, Yengo's team confirmed this fast rate of the powerstroke and with additional studies demonstrated that the key biochemical steps happened subsequently and much more slowly. Further analysis revealed for the first time how these events might be coordinated by the intramolecular motions deep inside the myosin molecule.

"Chris Yengo collected his data separate from mine and we combined and integrated the results," Debold says. "I could see things that he couldn't, and he could see things that I couldn't, and in combination we were able to reveal novel insights into how a molecular motor transduces energy. It was clear that the mechanics happened first followed by the biochemical events."

Highlighting the importance of examining energy transduction at the nanoscale level has very broad implications, Debold explains. "It's not just about how muscle works," he says. "It is also a window into how many motor enzymes within our cells transduce energy, from those that drive muscle contraction to those that cause a cell to divide."

Detailed knowledge about that process could help scientists one day develop treatments for such conditions as heart failure, cancer and more. "If you understand how the molecular motor works, you could use that information to improve function when it's compromised, as in the case of heart failure," Debold says. "Or if you wanted to prevent a tumor cell from dividing, you could use this information to prevent force-generation. Knowing exactly how force-generation occurs could be very useful for somebody trying to develop a drug to inhibit a molecular motor during cell division, and ultimately cancer."

Astronomers are winding back the clock on the expanding remains of a nearby, exploded star. By using NASA's Hubble Space Telescope, they retraced the speedy shrapnel from the blast to calculate a more accurate estimate of the location and time of the stellar detonation.

The victim is a star that exploded long ago in the Small Magellanic Cloud, a satellite galaxy to our Milky Way. The doomed star left behind an expanding, gaseous corpse, a supernova remnant named 1E 0102.2-7219, which NASA's Einstein Observatory first discovered in X-rays. Like detectives, researchers sifted through archival images taken by Hubble, analyzing visible-light observations made 10 years apart.

The research team, led by John Banovetz and Danny Milisavljevic of Purdue University in West Lafayette, Indiana, measured the velocities of 45 tadpole-shaped, oxygen-rich clumps of ejecta flung by the supernova blast. Ionized oxygen is an excellent tracer because it glows brightest in visible light.

To calculate an accurate explosion age, the astronomers picked the 22 fastest moving ejecta clumps, or knots. The researchers determined that these targets were the least likely to have been slowed down by passage through interstellar material. They then traced the knots' motion backward until the ejecta coalesced at one point, identifying the explosion site. Once that was known, they could calculate how long it took the speedy knots to travel from the explosion center to their current location.

According to their estimate, light from the blast arrived at Earth 1,700 years ago, during the decline of the Roman Empire. However, the supernova would only have been visible to inhabitants of Earth's southern hemisphere. Unfortunately, there are no known records of this titanic event.

The researchers' results differ from previous observations of the supernova's blast site and age. Earlier studies, for example, arrived at explosion ages of 2,000 and 1,000 years ago. However, Banovetz and Milisavljevic say their analysis is more robust.

"A prior study compared images taken years apart with two different cameras on Hubble, the Wide Field Planetary Camera 2 and the Advanced Camera for Surveys (ACS)," Milisavljevic said. "But our study compares data taken with the same camera, the ACS, making the comparison much more robust; the knots were much easier to track using the same instrument. It's a testament to the longevity of Hubble that we could do such a clean comparison of images taken 10 years apart."

The astronomers also took advantage of the sharp ACS images in selecting which ejecta clumps to analyze. In prior studies, researchers averaged the speed of all of the gaseous debris to calculate an explosion age. However, the ACS data revealed regions where the ejecta slowed down because it was slamming into denser material shed by the star before it exploded as a supernova. Researchers didn't include those knots in the sample. They needed the ejecta that best reflected their original velocities from the explosion, using them to determine an accurate age estimate of the supernova blast.

Hubble also clocked the speed of a suspected neutron star--the crushed core of the doomed star--that was ejected from the blast. Based on their estimates, the neutron star must be moving at more than 2 million miles per hour from the center of the explosion to have arrived at its current position. The suspected neutron star was identified in observations with the European Southern Observatory's Very Large Telescope in Chile, in combination with data from NASA's Chandra X-ray Observatory.

"That is pretty fast and at the extreme end of how fast we think a neutron star can be moving, even if it got a kick from the supernova explosion," Banovetz said. "More recent investigations call into question whether the object is actually the surviving neutron star of the supernova explosion. It is potentially just a compact clump of supernova ejecta that has been lit up, and our results generally support this conclusion."

So the hunt may still be on for the neutron star. "Our study doesn't solve the mystery, but it gives an estimate of the velocity for the candidate neutron star," Banovetz said.

In addition to a skin rash, many eczema sufferers also experience chronic itching, but sometimes that itching can become torturous. Worse, antihistamines -- the standard treatment for itching and allergy -- often don't help.

New research from Washington University School of Medicine in St. Louis indicates that allergens in the environment often are to blame for episodes of acute itch in eczema patients, and that the itching often doesn't respond to antihistamines because the itch signals are being carried to the brain along a previously unrecognized pathway that current drugs don't target.

The new findings, published Jan. 14 in the journal Cell, point to a possible new target and strategy to help eczema patients cope with those episodes of acute, severe itch.

"Years ago, we used to think that itch and pain were carried along the same subway lines in the nerves to the brain, but it turned out they weren't, and these new findings show there's another pathway entirely that's causing these episodes of acute itching in eczema patients," said principal investigator Brian S. Kim, MD, a dermatologist and an associate professor of medicine. "The itch can be maddening. Patients may rate their chronic itch at around a 5 on a scale of 10, but that goes up to 10 during acute itch flares. Now that we know those acute flares are being transmitted in an entirely different way, we can target that pathway, and maybe we can help those patients."

The typical pathway for itching in eczema patients involves cells in the skin that are activated and then release histamine, which can be inhibited with antihistamine drugs. But with this acute itching, a different type of cell in the bloodstream transmits itch signals to the nerves. Those cells produce too much of another non-histamine substance that triggers itch; therefore, antihistamines don't work in response to such signals.

"We've connected acute itching in eczema to allergic reactions transmitted by an entirely different population of cells," said Kim, also the co-director of the Center for the Study of Itch & Sensory Disorders. "In patients who experience episodes of acute itching, their bodies react in the same way as in people with acute allergy. If we can block this pathway with drugs, it might represent a strategy for treating not only itch but other problems, including perhaps hay fever and asthma."

In recent years, several clinical studies have tested a strategy that involves blocking Immunoglobulin E (IgE), a substance produced by the immune system in response to allergens. Patients with allergies produce IgE, causing allergic reactions, but its role in itch has been unclear.

Reviewing data from clinical studies of drugs aimed at treating chronic itching, Kim found a pattern in which patients reported episodes of acute itching, often after exposure to environmental allergens. He also found that eczema patients who make IgE in response to allergens in the environment were more likely to experience those episodes of severe, acute itch.

"Environmental allergens actually promote this type of itch," he explained. "Say a patient with eczema goes to Grandma's house, where there's a cat, and that person's itching just goes crazy. It's likely cat dander is activating IgE, and IgE is activating itch."

Kim's team took these observations to the laboratory, where his team made a mouse model of eczema. Studying the animals, they found that when the mice made IgE, they began to itch. But unlike standard itch signals, in which cells in the skin called mast cells release histamine, the IgE in mice with eczema activated a type of white blood cell called a basophil. Those cells then activated an entirely different set of nerve cells than the cells that carry itch signals that respond to antihistamines.

The discovery that acute itching in eczema is linked to exposure to allergens may help them avoid things that make them itch intensely, including animals, dust, mold or certain foods. Meanwhile, it also offers drug companies new targets for treating itch in eczema patients, including proteins and molecules Kim's team has identified along this newly identified neuro-immune pathway.

The sun is the only star in our system. But many of the points of light in our night sky are not as lonely. By some estimates, more than three-quarters of all stars exist as binaries -- with one companion -- or in even more complex relationships. Stars in close quarters can have dramatic impacts on their neighbors. They can strip material from one another, merge or twist each other's movements through the cosmos.

And sometimes those changes unfold over the course of a few generations.

That is what a team of astronomers from the University of Washington, Western Washington University and the University of California, Irvine discovered when they analyzed more than 125 years of astronomical observations of a nearby stellar binary called HS Hydrae. This system is what's known as an eclipsing binary: From Earth, the two stars appear to pass over one another -- or eclipse one another -- as they orbit a shared center of gravity. The eclipses cause the amount of light emitted by the binary to dim periodically.

On Jan. 11 at the 237th meeting of the American Astronomical Society, the team reported more than a century's worth of changes to the eclipses by the stars in HS Hydrae. The two stars began to eclipse in small amounts starting around a century ago, increasing to almost full eclipses by the 1960s. The degree of eclipsing then plummeted over the course of just a half century, and will cease around February 2021.

"There is a historical record of observations of HS Hydrae that essentially spans modern astronomy -- starting with photographic plates in the late 19th century up through satellite images taken in 2019. By diving into those records, we documented the complete rise and fall of this rare type of eclipsing binary," said team leader James Davenport, a research assistant professor of astronomy at the UW and associate director of the UW's DIRAC Institute.

The eclipses of the two stars that make up HS Hydrae are changing because another body -- most likely a third, unobserved companion star -- is turning the orientation of the binary with respect to Earth. Systems like this, which are called evolving eclipsing binaries, are rare, with only about a dozen known to date, according to Davenport. Identifying this type of binary requires multiple observations to look for long-term changes in the degree of dimming, which would indicate that the orientation of the binary is changing over time.

HS Hydrae has such an observational record because, at 342 light- years away, it is a relatively close and bright system and the two stars orbit each other every 1.5 days. Scientists first reported that HS Hydrae was an eclipsing binary in 1965. In a 2012 paper, astronomers based in Switzerland and the Czech Republic reported that the amount of dimming from HS Hydrae decreased from 1975 through 2008, indicating that the two stars were eclipsing smaller and smaller portions of one another over time. That team also predicted that the eclipses would end around 2022.

Davenport and his team checked in on HS Hydrae using observations of the system in 2019 by the NASA's Transiting Exoplanet Survey Satellite, or TESS. They saw only a 0.0075-magnitude drop in light from HS Hydrae, a sign that the two stars were barely covering one another during eclipses. For comparison, eclipses in 1975 saw a more than 0.5-magnitude drop.

"Fifty years ago, these two stars were almost completely eclipsing each other. By the early 21st century, the degree of eclipse was around 10%, and in the most recent observations from 2019, they barely overlapped," said Davenport.

With these new data, the team now predicts that HS Hydrae eclipses will cease around February 2021.

The observations from the 1960s through 2019 catalogue the decline of HS Hydrae as an evolving eclipsing binary. But Davenport and his team also uncovered evidence for its rise. The Digital Access to a Sky Century at Harvard, or DASCH, is a digital catalog of photometric data taken from more than a century's worth of astro-photographic plates at Harvard University. The team mined this record and found observations of HS Hydrae from 1893 through 1955 that they could analyze to search for signs of dimming.

The researchers broke down DASCH observations of HS Hydrae by decade. From the late 19th century through the roaring '20s, HS Hydrae showed no measurable dimming. But things began to change in the 1930s, where they measured a modest 0.1-magnitude drop in brightness. The degree of dimming rose through the 1940s and peaked in the 1950s with a 0.5-magnitude drop in brightness.

Based off this 126-year history of HS Hydrae observations, the team predicts that the system will start eclipsing again around the year 2195. But, that assumes that the third companion -- which other teams have predicted is a small, dim M-dwarf star -- continues to behave as it has to date.

"We won't know for sure unless we keep looking," said Davenport. "The best we can say right now is that HS Hydrae has been changing constantly over the course of modern astronomy."

Missions like TESS will likely identify more evolving eclipsing binaries in the coming years. This should open new opportunities for astronomers to understand how star systems are built, as well as how they change over time -- whether they are busy, dynamic systems like HS Hydrae, or more quiet systems, like ours.