Culture

The sun provides a daunting source of electromagnetic disarray - chaotic, random energy emitted by the massive ball of gas arrives to Earth in a wide spectrum of radio frequencies. But in that randomness, Stanford researchers have discovered the makings of a powerful tool for monitoring ice and polar changes on Earth and across the solar system.

In a new study, a team of glaciologists and electrical engineers show how radio signals naturally emitted by the sun can be turned into a passive radar system for measuring the depth of ice sheets and successfully tested it on a glacier in Greenland. The technique, detailed in the journal Geophysical Research Letters on July 14, could lead to a cheaper, lower power and more pervasive alternative to current methods of collecting data, according to the researchers. The advance may offer large-scale, prolonged insight into melting ice sheets and glaciers, which are among the dominant causes of sea-level rise threatening coastal communities around the world.

A sky full of signals

Airborne ice-penetrating radar - the primary current means for collecting widespread information about the polar subsurface - involves flying airplanes containing a high-powered system that transmits its own "active" radar signal down through the ice sheet. The undertaking is resource-intensive, however, and only provides information about conditions at the time of the flight.

By contrast, the researchers' proof of concept uses a battery-powered receiver with an antenna placed on the ice to detect the sun's radio waves as they travel down to Earth, through the ice sheet and to the subsurface. In other words, instead of transmitting its own signal, the system uses naturally occurring radio waves that are already traveling down from the sun, a nuclear-powered transmitter in the sky. If this type of system were fully miniaturized and deployed in extensive sensor networks, it would offer an unprecedented look at the subsurface evolution of Earth's quickly changing polar conditions, the researchers say.

"Our goal is to chart a course for the development of low-resource sensor networks that can monitor subsurface conditions on a really wide scale," said lead study author Sean Peters, who conducted research for the study as a graduate student at Stanford and now works at the MIT Lincoln Laboratory. "That could be challenging with active sensors, but this passive technique gives us the opportunity to really take advantage of low-resource implementations."

A random advantage

In addition to visible and other kinds of light, the sun is constantly emitting radio waves across a wide, random spectrum of frequencies. The researchers used this chaos to their advantage: They recorded a snippet of the sun's radioactivity, which is like an endless song that never repeats, then listened for that unique signature in the echo that's created when the solar radio waves bounce off the bottom of an ice sheet. Measuring the delay between the original recording and the echo allows them to calculate the distance between the surface receiver and the floor of the ice sheet, and thus its thickness.

In their test on Store Glacier in West Greenland, the researchers computed an echo delay time of about 11 microseconds, which maps to an ice thickness of about 3,000 feet - a figure that matches measurements of the same site recorded from both ground-based and airborne radar.

"It's one thing to do a bunch of math and physics and convince yourself something should be possible - it's really something else to see an actual echo from the bottom of an ice sheet using the sun," said senior author Dustin Schroeder, an assistant professor of geophysics at Stanford's School of Earth, Energy & Environmental Sciences (Stanford Earth).

From Jupiter to the sun

The idea of using passive radio waves to collect geophysical measurements of ice thickness was initially proposed by study co-author Andrew Romero-Wolf, a researcher with NASA's Jet Propulsion Laboratory, as a way of investigating Jupiter's icy moons. As Schroeder and Romero-Wolf worked together with others on a mission, it became clear that radio waves generated by Jupiter itself would interfere with their active ice-penetrating radar systems. At one point, Romero-Wolf realized that instead of a weakness, Jupiter's erratic radio emissions might actually be a strength, if they could be turned into a source for probing the subsurface of the moons.

"We started discussing it in the context of Jupiter's moon Europa, but then we realized it should work for observing Earth's ice sheets too if we replace Jupiter with the sun," Schroeder said.

From there, the research team undertook the task of isolating the sun's ambient radio emissions to see if it could be used to measure ice thickness. The method involved bringing a subset of the sun's 200- to 400-megahertz radio frequency band above the noise of other celestial bodies, processing massive amounts of data and eliminating man-made sources of electromagnetism like TV stations, FM radio and electronic equipment.

While the system only works when the sun is above the horizon, the proof-of-concept opens the possibility of adapting to other naturally occurring and man-made radio sources in the future. The co-authors are also still pursuing their original idea of applying this technique to space missions by harnessing the ambient energy emitted by other astronomical sources like the gas giant Jupiter.

"Pushing the frontiers of sensing technology for planetary research has enabled us to push the frontiers of sensing technology for climate change," Schroeder said. "Monitoring ice sheets under climate change and exploring icy moons at the outer planets are both extremely low-resource environments where you really need to design elegant sensors that don't require a lot of power."

The treatment of many medical issues like abnormal gait and muscular disorders require an accurate sensing of applied pressure. In this regard, flexible pressure sensors that are simple, lightweight, and low-cost, have garnered considerable attention. These sensors are designed and manufactured through "additive manufacturing," or what is more commonly called "3D printing," using conductive polymer composites as their building blocks.

However, all 3D-printed pressure sensors developed so far are limited to sensing applied forces along a single direction only. This is hardly enough for real world applications, which involve situations where forces can be applied along various angles and directions. Moreover, the electrical resistance of most conductive polymers varies with temperature and must be compensated for accurate pressure sensing.

In a study published in Composites Part B: Engineering, a group of scientists led by Prof. Hoe Joon Kim from Daegu Gyeongbuk Institute of Science and Technology, South Korea, have addressed this issue with a newly designed multi-axis pressure sensor coupled with a temperature-sensing component that overcomes the limitations of conventional sensors. "Our multi-axis pressure sensor successfully captures the readings even when tilted forces are applied. Moreover, the temperature-sensing component can calibrate the resistance shift with temperature changes. In addition, the scalable and low-cost fabrication process is fully compatible with commercial 3D printers," explains Prof. Kim.

Scientists first prepared the printable conductive polymer using multi-walled carbon nanotubes (MWCNTs) and polylactic acid (PLA). Next, they built the sensor body with a commercial elastomer and sensing material with MWCNTs/PLA composite filament using 3D printing. The sensor is based on a bumper structure with a hollow trough beneath and employs three pressure-sensing elements for multi-axis pressure detection and a temperature-sensing element for calibration of resistance. The sensor could successfully calibrate both the magnitude and direction of the applied force by evaluating the response of each pressure-sensing element. This bumper structure, when installed in a 3D-printed flip-flop and a hand gripper, enabled clear distinction between distinct human motions and gripping actions.

The scientists are thrilled about the future prospects of their 3D-printed sensor. "The proposed 3D printing technology has a wide range of applications in energy, biomedicine, and manufacturing. With the incorporation of the proposed sensing elements in robotic grippers and tactile sensors, the detection of multi-directional forces along with temperature could be achieved, heralding the onset of a new age in robotics," comments an excited Prof. Kim.

Indeed, those are some interesting consequences to look forward to!

CHAMPAIGN, Ill. -- Sharing ideas in an online learning environment has a distinct advantage over sharing personal details in driving learner engagement in massive open online courses, more commonly known as MOOCs, says new research co-written by a University of Illinois Urbana-Champaign expert who studies the intersection of marketing and digital environments.

Online learning engagement can be increased by nearly one-third by simply prompting students to share course ideas in a discussion forum rather than having them share information about their identity or personal motivations for enrolling, said Unnati Narang, a professor of business administration at the Gies College of Business.

With less than 10% of online learners completing courses, and less than 5% participating in course discussions, there's a stark need for online learning platforms to identify and employ strategies that can enhance student engagement, Narang said.

"Engagement levels have tended to be really low in online classrooms simply because students may not ever get the chance to get to know each other in the way they do in an in-person, face-to-face classroom," she said. "A lot of those elements are, quite obviously, lacking in the online learning environment."

Initially, online platforms placed a lot of emphasis on having discussion forums to engage students. But over time, those efforts tended to fizzle out, Narang said.

"Even if a student is posting something, it may never be read by a classmate or by the instructor, which can really demotivate students who are trying to engage in the material," she said.

To determine how to increase learner engagement, Narang and her co-authors analyzed more than 12,000 discussion forum postings during an 18-month period and conducted a field experiment involving more than 2,000 learners in a popular online course offered by a large U.S. university.

"We randomly nudged students to either share something personal about themselves or ideas related to the course," she said. "We thought we were going to see an increase in engagement thanks to the social aspects of identity sharing because there's so much emphasis on it in face-to-face classes for icebreakers and social introductions."

The results indicated that asking learners to share ideas related to the course had a stronger effect on their video consumption and assessment completion, according to the paper.

"We found that the idea of sharing knowledge outperforms identity sharing as well as the control condition of not sharing anything," Narang said. "Across diverse metrics of learner engagement and performance, we found that what learners share plays a big role in enhancing the online learning environment, and they tended to perform 30% better in terms of how many videos they consumed, how many assessments they completed and how they scored on assessments. So there's a distinct advantage to idea sharing in online pedagogy."

For educators, the implications of what the researchers dubbed the "idea advantage" in an era of increased online learning due to the COVID-19 pandemic suggests that identity sharing tends to be superficial and brief, so it's better to push students to engage more on the course content and their ideas about what they're studying, Narang said.

"Just very basic getting-to-know-you introductions that instructors make in a physical classroom - who are you, where you're from, etc. - doesn't really translate into the online learning environment," she said. "There's just too much anonymity to successfully do that when you're in a virtual classroom. The idea posts, on the other hand, tend to be much more elaborate and well-articulated. Students put more time and effort into crafting their answers. On average, an idea-sharing post was 66 words long. But an identity-sharing post tended to be roughly half as long. Students were clearly more invested in ideas than trying to make friends in the online learning environment, thus why the idea advantage is so strong."

A new study finds forensics researchers use terms related to ancestry and race in inconsistent ways, and calls for the discipline to adopt a new approach to better account for both the fluidity of populations and how historical events have shaped our skeletal characteristics.

"Forensic anthropology is a science, and we need to use terms consistently," says Ann Ross, corresponding author of the study and a professor of biological sciences at North Carolina State University. "Our study both highlights our discipline's challenges in discussing issues of ancestral origin consistently, and suggests that focusing on population affinity would be a way forward."

Race is a social construct - there's no scientific basis for it. Population affinity, in the context of forensic anthropology, is determined by the skeletal characteristics associated with groups of people. Those characteristics are shaped by historic events and forces such as gene flow, migration, and so on. What's more, these population groups can be very fluid.

In practical terms, that this means that race can be wildly misleading in a forensic context. For example, a missing person may have been listed as Black on their driver's license because of their skin color. But their skeletal remains may not indicate they were of African descent, because their bone structure may reflect other aspects of their ancestry.

"Like many disciplines, forensic anthropology has been coming to terms with issues regarding race," Ross says. "Some people in the discipline want to do away completely with assessing an individual's place of origin. Others say that conventional approaches still have value in helping to identify human remains.

"In this paper, we are recommending a third path. This study is focused on finding ways to evaluate human variation that give us valuable information in forensic and anthropological contexts, but that avoid clinging to the use of outdated defaults such as race."

In one part of the study, the researchers looked at all of the papers published in the Journal of Forensic Sciences between 2009 and 2019 that referenced ancestry, race or related terms. The goal of this content analysis was to determine if the terms were being used consistently within the field. And they were not.

"The Journal of Forensic Sciences is the flagship journal for forensic sciences in the U.S., and even there we found inconsistencies in how our field uses these terms," Ross says. "Inconsistent terminology opens the door to confusion, misunderstanding and misuse within the discipline."

In a second part of the study, the researchers used geometric morphometric data and spatial analysis methods to evaluate the validity of terms such as "European" or "African" to describe the ancestral origin of human remains.

Altogether, the researchers evaluated nine datasets, comprising data on 397 people. The datasets were of human remains collected in Chile, Colombia, Cuba, Guatemala, Panama, Puerto Rico, Peru, Spain and a population of enslaved Africans that had been buried in Cuba. All of the remains, except for those of the enslaved Africans, were from the 20th or 21st centuries.

"Regarding the data we have on the remains of enslaved Africans, we want to acknowledge the value that data collected from such samples can contribute to discussions of human variation, while also noting that the history and ethics of human skeletal collections, in general, is often dubious," Ross says. "Such body harvesting all too often occurred under the umbrella of scientific racism, without the permission of the deceased or next of kin, and disproportionately targeted marginalized populations."

In their review of recent papers, the researchers found that forensics experts often still referred to remains as being of African, Asian or European origin.

"But our analysis of these nine datasets shows that this approach is wrong, because it's not that simple," Ross says.

"Let's use Panama as an example," says Ross, who is from Panama. "There have been huge movements of people into this area from all over the world over the past 500 years: indigenous peoples who predate colonialism, colonizers from Europe, slaves from Africa, immigrants from Asia. The contemporary remains we see in Panama reflect all of those influences."

Ross also noted that the analysis of the nine datasets also highlighted a flaw in the contemporary idea of "clines." The idea of clines is basically that, while there are changes from one group of people to another, populations who are geographically close to each other are more similar than populations that are geographically distant. However, the researchers found that this assumption can be misleading.

For example, Panama and Colombia share a border, but very different historical forces have acted on Panama and Colombia in recent centuries - so the skeletal characteristics of remains from those two countries are much less similar than one would anticipate.

"All of this is important for multiple reasons, such as taking meaningful steps to reduce racism in our field, and ensuring that we are communicating clearly with each other within the discipline," Ross says. "It is also important because marginalized people are most often the people whose remains go unidentified. Labeling them as 'Hispanic' or 'Black' is misleading. We, as forensic anthropologists, need to change the way we think about origin. We need to begin thinking about physical markers in the context of population affinity and how we can use that to both communicate clearly and to help understand who we are seeing when we work with unidentified remains. We need to ensure that we are not contributing - even inadvertently - to structural inequities and racism.

"This also means that we are faced with a wide range of new research questions. As a field, much of our work has focused on looking at data from the remains of historic populations. I think we need to begin doing more work that can help us better understand the ways in which historical events have helped to shape the skeletal characteristics of modern populations."

When a doctor gives a patient antibiotics for a bacterial infection, they usually require them to finish the entire treatment, even when symptoms go away. This is to ensure the drugs kill off any remaining bacteria. Cold Spring Harbor Laboratory (CSHL) Visiting Scientist Raffaella Sordella investigated a similar problem that occurs in some lung cancers.

Approximately 15% of non-small cell lung cancers have a mutation in a growth receptor called EGFR, causing tumor cells to grow uncontrollably. Researchers developed an effective drug that inhibits EGFR and kills cancer cells, but the tumor grows back later. Sordella wanted to understand the molecular mechanisms behind this relapse and how to prevent it.

Sordella and her team discovered that a small percentage of drug-resistant cancer cells were already present before treatment. Instead of relying on EGFR, these cells are dependent on another gene (AXL) for survival. Furthermore, they observed that the cells could transition between these drug-sensitive and drug-resistant "states." When patients finish EGFR treatment, random modifications constantly occur in the remaining cells, causing both types of cells to grow back.

Sordella and her team worked with clinicians at Northwell Health and former CSHL Professor Gregory Hannon, now at the Cancer Research UK Cambridge Institute. Hannon's research focuses on microRNA, a molecule that regulates cells by managing transcribed (copied) genes. Sordella explains:

"The genome is like a library. So when you have to do a recipe to bake something, you go there, you transcribe your recipe, you take it out from the library, you go in the kitchen. What these microRNAs do, they intercept all the recipes that are getting out from your library. And then, they decide whether this is a recipe that the cell should care about or not. So they are what they call 'gatekeepers' of a cell state."

The researchers discovered that a certain microRNA called miR335 determines the "state" of the cancer cell. If the cancer cell loses miR335, a cascade of events is triggered that allows cells to use the alternative AXL pathway; the cells are not killed by drugs that target EGFR. These drug-resistant cells survive and eventually, the tumor grows back.

Understanding how resistance arises in lung cancer is key to figuring out how to eliminate a tumor. Sordella hopes that these findings could help develop treatments to wipe out both AXL- and EGFR-dependent cells from the start.

LEXINGTON, Ky. (July 13, 2021) -- A recently published study co-authored by University of Kentucky Sanders-Brown Center on Aging researcher Justin Miller, Ph.D., identifies 11 rare candidate variants for Alzheimer's disease. Researchers found 19 different families in Utah that suffered from Alzheimer's disease more frequently than what is considered normal.

Miller, an assistant professor in the UK College of Medicine, was a co-first author for the study published in the journal Alzheimer's & Dementia. The work was started at another university, however, some of the computational work was done after Miller arrived at UK in March.

For the study, genetic sequencing was conducted on two cousins from each of the 19 families. Miller says they then identified genetic variants that were shared between both cousins.

"We then used a series of filtering criteria to identify rare genetic variants that were most likely contributing to the excess Alzheimer's disease in each family," he said.

Researchers found 11 rare genetic variants spanning 10 genes, including previously unknown variants in two known Alzheimer's disease risk genes.

"Identifying people with increased risk for Alzheimer's disease before they become symptomatic may lead to earlier and more effective interventions," Miller said. "Additionally, our methodology for analyzing high-risk pedigrees can be used to prioritize rare genetic variants that likely contribute to disease."

Miller says while this discovery will not immediately impact patient care, they do believe identifying genetic variants associated with the disease is the first step to identifying potential drug targets that can be used to develop therapeutics.

This work was funded by the National Institutes of Health, the Huntsman Cancer Institute, Brigham Young University, University of Utah, National Cancer Institute, BrightFocus Foundation, the National Heart, Lung, and Blood Institute, and was a collaboration with Brigham Young University, the University of Utah, and the Alzheimer's Disease Genetics Consortium.

Research reported in this publication was supported by the National Institute on Aging of the National Institutes of Health under Award Numbers RF1AG054052 and U01AG052411. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

The University of Kentucky is increasingly the first choice for students, faculty and staff to pursue their passions and their professional goals. In the last two years, Forbes has named UK among the best employers for diversity, and INSIGHT into Diversity recognized us as a Diversity Champion four years running. UK is ranked among the top 30 campuses in the nation for LGBTQ* inclusion and safety. UK has been judged a "Great College to Work for" three years in a row, and UK is among only 22 universities in the country on Forbes' list of "America's Best Employers." We are ranked among the top 10 percent of public institutions for research expenditures -- a tangible symbol of our breadth and depth as a university focused on discovery that changes lives and communities. And our patients know and appreciate the fact that UK HealthCare has been named the state's top hospital for five straight years. Accolades and honors are great. But they are more important for what they represent: the idea that creating a community of belonging and commitment to excellence is how we honor our mission to be not simply the University of Kentucky, but the University for Kentucky.

In addition to chemical factors, mechanical influences play an important role in the natural growth of human organs such as kidneys, lungs and mammary glands - but also in the development of tumors. Now a research team at the Technical University of Munich (TUM) has investigated the process in detail using organoids, three-dimensional model systems of such organs which are produced in the laboratory.

Organoids are three-dimensional systems modeling various human organs. Grown in the laboratory, they exhibit properties similar to those of actual body tissue. Organoids offer science new opportunities to simulate and investigate the processes of organ growth. These processes could not be observed in the simplified two-dimensional model systems used in the past.

Using mammary gland organoids to analyze the complex interactions of cells with surrounding tissue, scientists at the Technical University of Munich, the Helmholtz Zentrum München and the Ruhr-Universität Bochum have shown, that the growth of the gland tissue in the human breast is explicitly influenced by the mechanical properties of the surrounding collagen network.

Integrated dynamic development process

The organoids grown by the team form branched glandular ducts whose structure and organization very closely resemble that of the human mammary gland. During the growth process the individual organoid branches invade into the surrounding collagen matrix.

"Starting with a single stem cell, in just 14 days these organoids form a complex, branched, three-dimensional structure consisting of several thousand cells. This is absolutely fascinating," says Andreas Bausch, Professor for Cellular Biophysics at TU Munich and head of the research group.

The research team used temporally resolved microscopy on the growing structures over the course of several days and successfully monitored the dynamic development process in detail. They discovered that the organoid growth is substantially dictated by collective movements of the cells.

By expanding in the direction of movement and then contracting again, the cells generate forces so strong that they deform the surrounding collagen matrix, making it possible for the organoid to independently organize the direction of its own further growth.

Stable collagen 'cage'

"This is made possible by the mechanical plasticity of the collagen," says Benedikt Buchmann, lead author of the research team's study. "When the individual cells move back and forth collectively they produce such tension that the cells of a branch can deform the collagen matrix."

The overall process results in the formation of a mechanically stable collagen 'cage' which ultimately surrounds the growing branch. This collagen cage then controls the further generation of tension, the growth of the branches and the plastic deformation of the matrix.

These findings provide the basis for the use of this model system to investigate more complex processes such as the first steps in metastasis or mutual interaction with other cell types. Intensive current research is now on the way to determine whether this self-organization mechanism also occurs in other organs.

The COVID-19 pandemic changed just about every aspect of normal life, including how we bought food.

While grocery stores remained open as an essential business and thrived financially throughout the pandemic, this prosperity did not translate to a consistent and sufficient food supply for many customers. Researchers have found that, on average, people went to the grocery store less frequently and spent more per trip during the pandemic.

Ran Xu, professor of allied health sciences in the College of Agriculture, Health, and Natural Resources, was interested in seeing if this trend applied to people who are food-insecure. COVID-19 exacerbated food insecurity for many. Pandemic-related job loss and other factors also led to an increase in overall rates of food insecurity.

"Because of how COVID-19 hit the economy, more people were suddenly food-insecure, and we needed more research on that," Xu says.

Xu and collaborators recently published a paper in Public Health that evaluated how perceived risk aversion, resource scarcity, and the consumers' food security status affected food procurement behaviors during this moment of national strife. They found that like food-secure individuals, food-insecure individuals made fewer grocery shopping trips due to concerns about contracting COVID-19. But, unlike food-secure individuals, they did not increase spending per trip.

"We think this is a serious issue that shows that COVID-19 impacts different populations differently," Xu says. "The findings we have are worrisome."

The researchers focused on food-insecure individuals who have considerable financial difficulty in procuring food.

They measured food insecurity according to two measures from the USDA's longer food insecurity survey. They asked respondents if they worried their food supply would run out before they had money to buy more, and if the food they bought just didn't last and they didn't have money to get more.

Then, the researchers evaluated participants' food shopping behaviors, such as types of stores they patronize, frequency of trips, and average food expense. They compared these measures with their shopping experience before the pandemic.

Their results showed that, of the 2,500 respondents from around the country, food-secure individuals tended to spend more per trip to stockpile food, reduce the potential for COVID-19 exposure, and prepare for food shortages. But food-insecure individuals could not prepare in the same way as they had much more constrained budgets and resources. Although food-insecure people made fewer grocery shopping trips due to concerns about contracting COVID-19, unlike food-secure people, they did not increase spending per trip.

The team conducted the study in May 2020, during the height of the pandemic in the U.S.

These findings show that the pandemic exacerbated the disparity between food-secure and insecure people.

Food insecurity has serious health consequences. Lack of access or lack of reliable access to nutritious foods contributes to a host of diseases including diabetes and cardiovascular disease.

"Food has everything to do with our health," Xu says. "Food insecurity adds another layer to that."

Arlington, VA (July 13, 2021) -- Hospitals and other healthcare facilities should require employees to be vaccinated against COVID-19, according to a consensus statement by the Society for Healthcare Epidemiology of America (SHEA) and six other leading organizations representing medical professionals working in infectious diseases, infection prevention, pharmacy, pediatrics, and long-term care. The paper specifies exemption for those with medical contraindications, and some others circumstances in compliance with federal and state laws.

"The COVID-19 vaccines in use in the United States have been shown to be safe and effective," said David J. Weber, a member of the SHEA Board of Trustees and lead author of the statement. "By requiring vaccination as a condition of employment we raise levels of vaccination for healthcare personnel, improve protection of our patients, and aid in reaching community protection. As healthcare personnel, we're committed to these goals."

SHEA convened a multiorganizational panel of experts in infectious disease prevention, law, and human resources, with representatives from AMDA - The Society for Post-Acute and Long-Term Care Medicine, The Association for Professionals in Infection Control and Epidemiology (APIC), the Infectious Diseases Society of America (IDSA), the HIV Medicine Association (HIVMA), the Pediatric Infectious Diseases Society (PIDS), and the Society of Infectious Diseases Pharmacists (SIDP). The panel conducted an eight-week review of evidence on the three vaccines authorized for use in the United States, vaccination rates, and employment law to develop the statement.

Research shows that prior to the pandemic, rates of routine vaccinations among healthcare providers were suboptimal. For flu vaccination, when healthcare employers instituted policies of influenza vaccination as a condition of employment, compliance rose to 94.4 percent compared to 69.6 percent in organizations without a requirement.

Over 33 million Americans have contracted COVID-19 and more than 600,000 have died. The COVID-19 vaccines authorized for use in the United States have been found safe and effective in preventing infection and reducing transmission. Studies have demonstrated that the COVID-19 vaccines authorized for use in the US also protect against variants, and are particularly effective against severe disease, hospitalization, and death.

Despite the positive data, there are still many healthcare professionals who have declined to be vaccinated against COVID-19.

"Vaccinating the healthcare workforce reduces the risk of transmission by protecting patients, healthcare personnel, and communities, and maintains trust in healthcare providers and healthcare institutions," Weber said.

The statement explains what to consider in developing a policy of COVID-19 vaccination as a condition of employment, including a thorough overview of current vaccines' safety and efficacy, legal considerations, ways to engage stakeholders and improve vaccination rates before implementing a policy of vaccination as a condition of employment, and advantages to having a fully vaccinated workforce.

A blood test that quantifies the protein ACE2, the cellular protein which allows entry of the coronavirus into cells, as well as ACE2 fragments, produced as a result of interaction with the virus, could be a simple and effective method for monitoring SARS-CoV-2 infection, according to a study led by Javier Sáez-Valero, from the UMH-CSIC Neurosciences Institute in Alicante, published in FASEB Journal.

This study, carried out during the first wave of the pandemic, found that patients with COVID-19, in the acute phase of infection, have significantly reduced plasma levels of the full-length ACE2 protein, which SARS-CoV-2 binds to enter cells, compared to non-infected controls. In addition, the plasma levels of a lower molecular mass (70 kDa) ACE2 fragment, generated as a result of interaction with the virus, are increased.

These abnormal levels of ACE2 and truncated ACE2 (70 kDa fragment) return to normal after the patients' recovery. This suggests that both forms of ACE2 present in plasma could be used as a good biomarker of the evolution of coronavirus infection. In addition, truncated ACE2 levels served to discriminate between patients infected with SARS-CoV-2 and those infected with influenza A virus.

"In this work we have studied the plasma levels of the coronavirus receptor, the ACE2 protein, and we have been able to determine that there are different forms of the protein in plasma, and that part of the soluble ACE2 are proteolytic fragments of the ACE2 receptor, generated subsequently to interaction with the virus. The full-length protein is also found in plasma, which provides information about tissue affection during infection," explains Javier Sáez-Valero, who led the study.

Although the main research line of Sáez-Valero's group is Alzheimer's Disease, the "similarities" of ACE2 to core proteins of Alzheimer's disease pathology, such as beta-amyloid precursor protein (APP), also cell membrane resident proteins, led this expert to think that perhaps ACE2 could be present in plasma, providing information on its interaction with the coronavirus.

"Our approach to this research line was the possibility that soluble ACE2 protein can serve as a read-out during infection with COVID-19. This hypothesis originates from our expertise in Alzheimer's disease. In this neurodegenerative disease we investigate proteins, such as APP, that are present in the cerebrospinal fluid. APP is also a membrane protein that is processed by the same molecular tools as ACE2, enzymes called secretases, which process several membrane proteins into different fragments. This phenomenon was the clue that led us to think that ACE2 protein fragments, but also the full-length protein, are present in plasma. Thus, we have the possibility of investigating this protein as a possible biomarker," explains Sáez-Valero.

TRIAL PARTICIPANTS

Samples and patient data included in this study were provided by the ISABIAL Biobank, integrated in the Spanish National Biobank Network and the Valencian Biobank Network. Fifty-nine patients with a positive reverse transcription polymerase chain reaction (RT-PCR) test for SARS-CoV-2 in nasopharyngeal swabs were included, of whom 24 were women and 35 men, with a mean age of 64 years). All were hospitalized 7 to 9 days after symptom onset. Of these, 48 SARS-CoV-2 infected patients suffered a moderate presentation of COVID-19, and 11 were considered severe as they suffered respiratory failure requiring invasive mechanical ventilation and/or intensive care unit treatment.

Two additional groups were also analyzed, one of 17 participants (9 women and 8 men), which included people aged 34 to 85 years with influenza A virus pneumonia. The other group consisted of 26 disease-free controls (14 women and 12 men) aged 34-85 years. For the "influenza A group", samples were also taken in the acute phase, before specific hospital treatment.

The ACE2 species in human plasma were identified by immunoprecipitation and western blotting, a technique that allows the detection of a specific protein in a blood or tissue sample, where there is a complex mixture of forms of the protein. Until now, plasma analyses carried out for the coronavirus had mostly used another technique called ELISA, which does not allow the different forms of the proteins to be determined.

Changes in truncated and full-length ACE2 species were also examined in serum samples from humanized K18-hACE2 mice inoculated with a lethal dose of SARS-CoV-2. These humanized mice carry the human gene that produces the ACE2 protein, allowing SARS-CoV-2 infection, which does not occur naturally due to lack of recognition of murine ACE2 by the virus.

The alterations in the forms of ACE2 present in plasma following SARS-CoV-2 infection observed in this study justify, according to the researchers, further investigation of their potential as biomarkers of the disease process, and also for assessing the efficacy of vaccination. The next step will be to investigate what happens to these proteins in asymptomatic PCR-positive or vaccinated individuals.

Philadelphia, July 13, 2021 - Consumers may have less trust in food processes that they don't understand, and animal-based foods may be subject to more uninformed scrutiny than other foods due to consumers' perception of higher risk. Dairy producers can benefit from understanding how consumers interpret unfamiliar terms and claims on dairy product labels. In a new study appearing in the Journal of Dairy Science®, scientists from North Carolina State University conducted interviews and surveyed more than 1,200 consumers regarding their knowledge of and attitudes toward dairy processing terms that may appear on product labels.

Only about a third of respondents reported that they always or often read labels before purchasing dairy products; however, product labels are the primary source of information about food purchases used by consumers. This is reflected by the fact that only 24 percent of respondents were familiar with microfiltered milk, and no respondents could recall seeing the term on dairy product labels. Despite this, 20 percent expressed a negative opinion of it.

"Our survey data align with previous work that suggests the majority of dairy product consumers find both milk and cheese healthy and natural," said corresponding author MaryAnne Drake, PhD, North Carolina State University, Raleigh, NC, USA. "However, adding processing-related terms to 'milk' lowered average agreement that the resulting product was natural or healthy." Overall, agreement responses suggest that although overall dairy product consumers have a positive view of milk, processing terms introduce uncertainty that may lead to questioning this evaluation.

Providing education about processing terms improves consumer understanding and perception of those terms on labels. Before reading a definition of ultrafiltration and microfiltration, 83 percent of respondents were unfamiliar with the terms. After reading the definition, 97 percent of participants indicated that their understanding had changed. The majority of participants viewed ultrafiltered and microfiltered milk more positively and were more likely to purchase these products.

"Processing-related descriptors in ingredient statements are likely to be overlooked, especially on the labels of products with which consumers already feel familiar. However, consumers may express caution when they are made aware of unfamiliar processing terms," added Drake.

The study suggests that explaining processing-related terms using simple terms may increase positive perception among consumers. On-package education and other marketing messaging should be investigated further.

New research from the University of Nebraska-Lincoln has shown that the mutations arising in the COVID-19-causing SARS-CoV-2 virus seem to run in the family -- or at least the genus of coronaviruses most dangerous to humans.

After comparing the early evolution of SARS-CoV-2 against that of its closest relatives, the betacoronaviruses, the Nebraska team found that SARS-CoV-2 mutations are occurring in essentially the same locations, both genetically and structurally.

The mutational similarities between SARS-CoV-2 and its predecessors, including the human-infecting SARS-CoV-1 and MERS-CoV, could help inform predictions of how the COVID-causing virus will continue to evolve, the researchers said.

"The problem of looking at only one virus at a time is that you lose the forest for the trees," said Katherine LaTourrette, a doctoral student in the Complex Biosystems program at Nebraska. "By looking at this big picture, we were able to predict the mutational nature of SARS-CoV-2.

"That gets into these questions of: Are vaccines going to be effective long term? Which variants are going to sneak by? Do we need that booster shot? Are vaccinated people going to be infected a second time?"

'YOU'RE MORE LIKELY TO BE HITTING THAT BULL'S-EYE'

The genetic code of a virus determines its ability to infect cells and direct them to churn out more copies of itself. That code consists of fundamental compounds, or nucleotides, with mutations occurring wherever those nucleotides get added, subtracted or swapped for one another. Many mutations have little or no effect, in the same way that trying to hack an intricate password by changing just one character will likely fail.

But given enough chances, a virus will eventually happen upon a mutation or mutations that change the assembly of its structural joints, or amino acids, enough to help it better invade cells and replicate -- advantages that help it outcompete other strains. In some cases, a new strain can also evade the immune responses stirred by existing vaccines, necessitating the development of new vaccines to protect against it.

LaTourrette and her adviser, Hernan Garcia-Ruiz, were busy comparing mutational patterns across viruses that invade a different biological kingdom -- plants -- when the SARS-CoV-2 pandemic struck. To do it, the researchers were analyzing segments of sequenced DNA from parallel locations on the genomes of all viruses in a genus. They were hunting specifically for single-point mutations: segments in which just one nucleotide had changed. By pinpointing them, the team was sussing out whether certain mutations pop up across related plant viruses, then tracing those mutations to functional amino acid changes in the viruses.

"A lot of times, researchers have a specific plant virus they study," LaTourrette said. "They know it really well. But our question was: Big picture, what is the genus doing? We know that variation isn't random. It accumulates in specific areas of the genome, and those areas are (sometimes) consistent across the genus. Those tend to be areas important for things like host adaptation -- basically, areas that are going to need to keep changing in order to keep co-evolving with their host.

"So when COVID-19 happened, we thought, well, we can download the (betacoronavirus) sequences and run them through the pipeline and see where the variation is occurring."

When they did, LaTourrette and her colleagues found that the so-called spike protein, which protrudes from betacoronaviruses and keys their entry into host cells by binding with receptors on the surface, mutates rapidly across all known betacoronaviruses, including SARS-CoV-2.

Despite accounting for just 17% of the SARS-CoV-2 genome, the "hyper-variable" spike protein has so far accumulated roughly 50% of the virus's total mutations, the researchers discovered. Those mutations are emerging in the same regions of the genome, and even the same sub-units of the spike protein, as they have in every other betacoronavirus to date.

"All of our analyses showed that that's really where the variation is happening," LaTourrette said. "It didn't matter when we looked at it, what variant we looked at -- the spike protein was key."

The team also concluded, as other virologists have, that the SARS-CoV-2 spike protein is disordered --that while its amino acids assemble into the same general architecture, that architecture has what LaTourrette called "some wiggle room" to shift into slightly different configurations. That's bad news, she said, given that its structural flexibility likely gives it some functional wiggle room, too.

"Humans may have slightly different cell receptors, person to person," LaTourrette said. "So then you have to have a (spike protein) receptor that can accommodate those little shifts. If it were very ordered, and it couldn't shift, then maybe it couldn't infect everyone. But by having that flexibility, it's a much better virus.

"Basically, this area is hyper-variable, and it's flexible. So it's the double whammy."

Those qualities will continue to make SARS-CoV-2 a formidable foe that requires vigilance to stave off for the foreseeable future, LaTourrette said. But knowing its strengths, and that the evolutionary history of other betacoronaviruses might serve as a reasonable preview of that future, should help virologists and vaccinologists strategize accordingly.

Vaccines may have to continue targeting the distinctive spike protein as SARS-CoV-2 evolves, but consulting the mutational patterns of betacoronaviruses could help researchers forecast which domains of the protein are most and least likely to mutate. And that could make a moving target much easier to hit, LaTourrette said.

"If you close your eyes when you're throwing a dart at a dartboard, it could go anywhere," she said. "But by looking at the other (betacoronavirus) species, you have an idea of where it's likely to land. And you're more likely to be hitting that bull's-eye."

Though LaTourrette has already returned to the kingdom of plants, she said the opportunity to adapt her work to such a pressing purpose proved gratifying at a time when gratification was in short supply.

"For us, getting to (transition) from plants to coronaviruses was a really positive way of showing that you can take your science and your knowledge, and you can apply it to the benefit of society," LaTourrette said. "We've seen some really great examples in the past year-and-a-half of groups making that shift.

"Even though this is a very difficult time, and there's a lot of hardship, I think it's really positive to see scientists come together and be able to contribute to a cause together."

LaTourrette and Garcia-Ruiz, an associate professor of plant pathology at the Nebraska Center for Virology, conducted the research with recent master's graduate Natalie Holste, doctoral student Rosalba Rodriguez-Peña and Raquel Arruda Leme, a visiting researcher from Brazil.

WASHINGTON--In cities and towns across the United States, neighborhoods with more Black, Hispanic and Asian residents experience hotter temperatures during summer heatwaves than nearby white residents, a new study finds. It is the first to show that the trend, documented in some major cities, is widespread, even in small towns, nationwide.  

According to the new nationwide study, these racial disparities exist because non-white neighborhoods tend to be more densely built up with buildings and pavement that trap heat and have fewer trees to cool the landscape.   

"Urban climate is different from temperatures outside the city," said co-author Susanne Benz, an environmental scientist who conducted this research at the University of California, San Diego, and is now at Dalhousie University. "Inside the city, temperatures are affected by the buildings surrounding you and by the surface of the streets." Dark pavement absorbs sunlight and releases the heat at night, while trees and other vegetation cool an area through transpiration, when they release water vapor through pores in the leaves.  

The new study is published in Earth's Future, AGU's journal for interdisciplinary research on the past, present and future of our planet and its inhabitants. The approach offers city planners and policymakers a way to identify disparities and to evaluate initiatives to address urban heat.    

Summer in the city

Summer heatwaves cause more than 700 deaths each year in the United States. When heat and humidity are so high that a body can no longer cool itself through sweating, heat stroke can set in, rapidly causing brain and organ damage. People who are older, have certain chronic health conditions or are physically exerting themselves are most at risk. Urban environments are commonly hotter than their rural counterparts, and temperatures can vary even within cities. Those few degrees can mean life or death for some residents.

Benz initially had the idea for this study after reading a New York Times article finding that neighborhoods the U.S. government redlined in the 1930s--meaning they classified them as poor investments because people of color lived there--are now hotter than white neighborhoods in the same cities. She and co-author Jennifer Burney, an Earth scientist at the University of California, San Diego, realized they could do a similar analysis for the entire country.   

Benz looked for urban heat patterns using land surface temperatures during summer heat waves collected by a NASA satellite. She subtracted the temperature of nearby rural locations to find variations in urban heat across towns and cities. Then she combined the temperature data with demographic information from the U.S. Census, looking at more than 1,000 counties to see who was most impacted. NOAA and USGS survey data allowed her to estimate how densely built up an area was, and the proportion of land covered by trees.  

The researchers found that in 76% of counties with more than 10 census tracts, poorer neighborhoods were notably hotter than wealthier ones, primarily due to physical differences--more pavement and people and fewer trees. Areas with a larger percentage of people of color or where people had less education also experienced higher temperatures.  

Big cities weren't the only places with race-related heat differences. Benz and Burney also saw the same patterns playing out in less developed areas. "It turns out that even your tiny towns have the same disparities," Benz said, "and this was something that really shocked me."  

The trend held up even when they took wealth out of the picture. When residents had a similar income, non-white neighborhoods still faced significantly higher temperatures than white ones in 71% of the counties.    

"The findings are really quite staggering," said Jeremy Hoffman, a climate scientist and chief scientist at the Science Museum of Virginia, who was not involved in the research. "These disparities exist across virtually every built environment in the country. Money doesn't grow on trees, but it is certainly concentrated underneath them across the U.S." 

How to beat urban heat  

The new analysis provides information for policymakers and establishes a way to evaluate the success of policies designed to address urban heat. "There's a lot of talk in Biden's administration about environmental justice but not so much clarity on what metrics might be used to evaluate policy proposals," said Burney. "These are very concrete metrics that can be tracked over time."  

Now that officials can recognize and measure urban heat disparities, the big question is how to fix them.   

Hoffman thinks it will take thoughtful investment to cool off hotter neighborhoods, such as planting trees at parks, bus stops and along pedestrian thoroughfares and providing incentives for green or white reflective roofs to cool buildings. These initiatives could dovetail with urban agriculture programs, solar panel installation, workforce development and other programs to more holistically address racial inequality.   

Benz hopes that this analysis will be useful for all communities, but especially for smaller towns, whose residents can use the information to understand where disparities exist and take steps to correct them--before they become entrenched through further urbanization. She created a website where interested users can visualize where heat extremes exist in their area. 

The COVID-19 pandemic caused an unprecedented disruption to health care delivery, with resources shifted toward telehealth services and mass viral testing. While early studies in the pandemic highlighted differences in health care utilization among patients with commercial insurance, data from publicly insured or uninsured “safety-net” patient populations continue to emerge.
A recent study from researchers at the University of Minnesota and Hennepin Healthcare Research Institute (HHRI) is among the first to examine how different socio-demographic groups used telehealth, outpatient (i.e., clinic), emergency department and inpatient (i.e., hospital) care to test for SARS-CoV-2, the virus that causes COVID-19. Their findings were recently published in JAMA Network Open.
The study was led by U of M School of Public Health graduate student Rohan Khazanchi. Along with others from Hennepin Healthcare and HHRI, researchers included Medical School Assistant Professor Tyler Winkelman, who is also with the U of M Robina Institute of Criminal Law and Criminal Justice, and HHRI Data Scientist Peter Bodurtha. The team analyzed anonymous electronic health record data for people with symptoms of viral illness who received SARS-CoV-2 testing at Hennepin Healthcare, a large safety-net health system in Minneapolis.
The study found that:

Patients who initiated testing via telehealth were disproportionately white and English-speaking, whereas patients who initiated testing through the emergency department were disproportionately Black, Native American, non-English-speaking and had one or more pre-existing conditions.
Testing initiated through telehealth and outpatient encounters was associated with lower rates of subsequent inpatient and intensive care unit care than testing initiated in more care-intensive settings, such as emergency departments.

"Inequities by race, ethnicity and language in where people seek SARS-CoV-2 testing may point to several structural root causes, including barriers to timely testing access, delays in care seeking, difficulty accessing telehealth services, and higher rates of pre-existing conditions among patients who require higher levels of care," said Khazanchi.
The researchers also added that the inequities could be partially explained by clinician and clinic variations in telehealth use.
“Without structural reforms, rapid implementation of telehealth and other new services may exacerbate inequities in access to care, particularly if these investments come at the expense of other care sites,” said Bodurtha.
The authors said that as investigators explore the effects of the COVID-19 pandemic on health use and patient outcomes, future research should continue to examine how and why the health care use of safety-net patients differs from commercially insured individuals to inform equity-oriented interventions.
The study was supported by the National Institutes of Health’s National Center for Advancing Translational Sciences (#UL1TR002494).

Journal

JAMA Network Open

DOI

10.1001/jamanetworkopen.2021.12857

A team of geneticists and archaeologists from Ireland, France, Iran, Germany, and Austria has sequenced the DNA from a 1,600-year-old sheep mummy from an ancient Iranian salt mine, Chehrābād. This remarkable specimen has revealed sheep husbandry practices of the ancient Near East, as well as underlining how natural mummification can affect DNA degradation.

The incredible findings have just been published in the international, peer-reviewed journal Biology Letters.

The salt mine of Chehrābād is known to preserve biological material. Indeed, it is in this mine that human remains of the famed "Salt Men" were recovered, dessicated by the salt-rich environment. The new research confirms that this natural mummification process - where water is removed from a corpse, preserving soft tissues that would otherwise be degraded - also conserved animal remains.

The research team, led by geneticists from Trinity College Dublin, exploited this by extracting DNA from a small cutting of mummified skin from a leg recovered in the mine.

While ancient DNA is usually damaged and fragmented, the team found that the sheep mummy DNA was extremely well-preserved; with longer fragment lengths and less damage that would usually be associated with such an ancient age. The group attributes this to the mummification process, with the salt mine providing conditions ideal for preservation of animal tissues and DNA.

The salt mine's influence was also seen in the microorganisms present in the sheep leg skin. Salt-loving archaea and bacteria dominated the microbial profile - also known as the metagenome - and may have also contributed to the preservation of the tissue.

The mummified animal was genetically similar to modern sheep breeds from the region, which suggests that there has been a continuity of ancestry of sheep in Iran since at least 1,600 years ago.

The team also exploited the sheep's DNA preservation to investigate genes associated with a woolly fleece and a fat-tail - two important economic traits in sheep. Some wild sheep - the asiatic mouflon - are characterised by a "hairy" coat, much different to the woolly coats seen in many domestic sheep today. Fat-tailed sheep are also common in Asia and Africa, where they are valued in cooking, and where they may be well-adapted to arid climates.

The team built a genetic impression of the sheep and discovered that the mummy lacked the gene variant associated with a woolly coat, while fibre analysis using Scanning Electron Microscopy found the microscopic details of the hair fibres consistent with hairy or mixed coat breeds. Intriguingly, the mummy carried genetic variants associated with fat-tailed breeds, suggesting the sheep was similar to the hairy-coated, fat-tailed sheep seen in Iran today.

"Mummified remains are quite rare so little empirical evidence was known about the survival of ancient DNA in these tissues prior to this study," says Conor Rossi, PhD candidate in Trinity's School of Genetics and Microbiology, and the lead author of the paper.

"The astounding integrity of the DNA was not like anything we had encountered from ancient bones and teeth before. This DNA preservation, coupled with the unique metagenomic profile, is an indication of how fundamental the environment is to tissue and DNA decay dynamics.

Dr Kevin G Daly, also from Trinity's School of Genetics and Microbiology, supervised the study. He added:

"Using a combination of genetic and microscopic approaches, our team managed to create a genetic picture of what sheep breeds in Iran 1,600 years ago may have looked like and how they may have been used.

"Using cross-disciplinary approaches we can learn about what ancient cultures valued in animals, and this study shows us that the people of Sasanian-era Iran may have managed flocks of sheep specialised for meat consumption, suggesting well developed husbandry practices."