. Scientific Frontline

Thursday, November 4, 2021

Deer may be reservoir for SARS-CoV-2

Researchers found that more than 80% of the white-tailed deer sampled in different parts of Iowa between December 2020 and January 2021 tested positive for SARS-CoV-2.
Image Credit: Heidi-Ann Fourkiller


More than 80% percent of the white-tailed deer sampled in different parts of Iowa between December 2020 and January 2021 tested positive for SARS-CoV-2. The percentage of SARS-CoV-2 positive deer increased throughout the study, with 33% of all deer testing positive. The findings suggest that white-tailed deer may be a reservoir for the virus to continually circulate and raise concerns of emergence of new strains that may prove a threat to wildlife and, possibly, to humans.

“This is the first direct evidence of SARS-CoV-2 virus in any free-living species, and our findings have important implications for the ecology and long-term persistence of the virus,” said Suresh Kuchipudi, Huck Chair in Emerging Infectious Diseases, clinical professor of veterinary and biomedical sciences, and associate director of the Animal Diagnostic Laboratory, Penn State. “These include spillover to other free-living or captive animals and potential spillback to human hosts. Of course, this highlights that many urgent steps are needed to monitor the spread of the virus in deer and prevent spillback to humans.”

According to Vivek Kapur, Huck Distinguished Chair in Global Health and professor of microbiology and infectious diseases, Penn State, while no evidence exists that SARS-CoV-2 can be transmitted from deer to humans, he believes hunters and those living in close proximity to deer may want to take precautions, including during contact with or handling the animals, by wearing appropriate personal protective equipment and getting vaccinated against COVID-19,” said Kapur.

Wednesday, November 3, 2021

Hungry caterpillars an underappreciated driver of carbon emissions

Outbreak of leaf-eating caterpillars

Outbreaks of caterpillars of invasive gypsy moths, Lymantria dispar dispar, and forest tent caterpillar moths, Malacasoma disstria occur at least every five years in temperate forests. The insects munch through so many leaves that the resulting decrease in leaf-fall and increase in insect excrement has been found to alter the cycling of nutrients, particularly carbon and nitrogen, between land and nearby lakes on a huge scale.

Nitrogen-rich insect excrement, called frass, can wash into lake water and act as fertilizer for microbes, which then release carbon dioxide into the atmosphere as they metabolize. The researchers suggest that in outbreak years the large quantities of frass will favor the growth of greenhouse gas-producing bacteria in lakes at the expense of algae that remove CO2 from the atmosphere.

“These insects are basically little machines that convert carbon-rich leaves into nitrogen-rich poo. The poo drops into lakes instead of the leaves, and this significantly changes the water chemistry - we think it will increase the extent to which lakes are sources of greenhouse gases,” said Professor Andrew Tanentzap in the University of Cambridge’s Department of Plant Sciences, senior author of the paper.

Expansion of universe directly impacts black hole growth

First rendered image of a black hole, illuminated by infalling matter
(Image credit: Jean-Pierre Luminet)
Over the past 6 years, gravitational wave observatories have been detecting black hole mergers, verifying a major prediction of Albert Einstein’s theory of gravity. But there is a problem—many of these black holes are unexpectedly large. Now, a team of researchers from the University of Hawaiʻi at Mānoa, the University of Chicago, and the University of Michigan at Ann Arbor, have proposed a novel solution to this problem: black holes grow along with the expansion of the universe.

Since the first observation of merging black holes by the Laser Interferometer Gravitational-Wave Observatory (LIGO) in 2015, astronomers have been repeatedly surprised by their large masses. Though they emit no light, black hole mergers are observed through their emission of gravitational waves—ripples in the fabric of spacetime that were predicted by Einstein’s theory of general relativity. Physicists originally expected that black holes would have masses less than about 40 times that of the Sun, because merging black holes arise from massive stars, which can’t hold themselves together if they get too big.

Comparison of black hole merger observations with predictions from the new model. The horizontal axis shows the total mass of both black holes in any individual merger, relative to the Sun’s mass.

The LIGO and Virgo observatories, however, have found many black holes with masses greater than that of 50 suns, with some as massive as 100 suns. Numerous formation scenarios have been proposed to produce such large black holes, but no single scenario has been able to explain the diversity of black hole mergers observed so far, and there is no agreement on which combination of formation scenarios is physically viable. This new study, published in the Astrophysical Journal Letters, is the first to show that both large and small black hole masses can result from a single pathway, wherein the black holes gain mass from the expansion of the universe itself.

1,800-plus ‘young’ volcanoes in the U.S. Southwest

The peaks of monogenetic volcanoes,
viewed across Lunar Lake in Nevada.
Credit: Greg Valentine
They’re born. They live once, erupting for a period that might last for days, years or decades. Then, they go dark and die.

This narrative describes the life of a monogenetic volcano, a type of volcanic hazard that can pose important dangers despite an ephemeral existence.

The landscape of the southwestern U.S. is heavily scarred by past eruptions of such volcanoes, and a new study marks a step toward understanding future risks for the region.

The research, which will be published on Nov. 2 in the journal Geosphere, provides a broad overview of what we know — and don’t know — about this type of volcanism in the U.S. Southwest over the past 2.58 million years, a geologic period known as the Quaternary.

During this time, more than 1,800 monogenetic volcanoes erupted in the region, according to a count covering Nevada, Utah, Arizona, Colorado, New Mexico and parts of California’s eastern edge. Add in the Pinacate volcanic field, located mostly in the Mexican state of Sonora, bordering Arizona, and the number goes up to over 2,200, scientists say. (The volcanoes included are ones whose ages are estimated to be in the range of the Quaternary, but many have not been precisely dated.)

“Monogenetic means ‘one life,’” says lead author Greg Valentine, a University at Buffalo volcanologist. “So a monogenetic volcano will erupt once, and that eruption may last for several days to several decades, but after that, the volcano is basically dead.

“In the United States, most volcanic hazards-related attention has rightly gone to places like Hawaii, and to the Pacific Northwest and Alaska, where we have big stratovolcanoes like Mount Rainier and Mount St. Helens, which will have many eruptive episodes over a long life, with widespread hazardous effects. In the past, these smaller monogenetic volcanoes really haven’t been looked at from a focus on hazards; they have been instead studied mainly for what they tell us about the deep earth. Recently, however, there has been more buzz in the research community about how we need to take a look at the kinds of hazards these volcanoes might pose.

Far-reaching ecological change in the eastern Mediterranean

Tropical wing snail (Conomurex persicus),
an Indo-Pacific species, off the Israeli coast (© Jan Steger)
Different ecological niches: Tropical species are profoundly changing the way ecosystems in the eastern Mediterranean - with hardly any consequences

Communities of introduced tropical species differ significantly in their biological properties from the native wildlife in the eastern Mediterranean, as an international team of researchers led by Jan Steger from the Institute of Paleontology found. As a result - and due to the progressive collapse of Mediterranean species - the shallow water ecosystems in the region are changing particularly profoundly. The study was published in the journal Global Ecology and Biogeography.

The eastern Mediterranean is undergoing dramatic ecological change - while native species are disappearing more and more, tropical organisms introduced through the Suez Canal, called Lesseps’s species, thrive splendidly as a result of ever warmer water temperatures. However, they do not directly displace the native species, but rather occupy "free niches", according to a study that has now been published in the Journal Global Ecology and Biogeography.

"To understand how the increase in tropical species affects the native fauna and the function of the ecosystems, one has to compare their biological properties - such as lifestyle or nutrition - with those of the native fauna," says Jan Steger, doctoral student and first author of the new one Study.

Laser Mapping in Southern Mexico Discovers Nearly 500 Ancient Sites

Using laser mapping data, researchers from The University of Texas at Austin and other national and international institutions have discovered 478 ancient ceremonial centers in southern Mexico. Most of the sites probably date to 1100-400 B.C., several centuries before the Classic Age (A.D. 250-950) of Maya civilization.

The findings, published in Nature Human Behavior, further scholars’ understanding of the origins of Mesoamerican civilizations, particularly about the relationship between Olmec and Maya cultures. The newly found sites demonstrate the influence of Olmec architectural innovations on Maya centers of the Classic Age and broaden our knowledge of how the Olmec civilization transformed their environment through agriculture.

Lidar (Light Detection and Ranging) is a technology that can penetrate vegetation to map three-dimensional forms of the ground and archaeological sites. This study used publicly available lidar data obtained by the Instituto Nacional de Estadística y Geografía (INEGI), a Mexican governmental organization. It covered an area of 85,000 square kilometers, equivalent to the island of Ireland, representing the largest archaeological lidar study of Mesoamerica.

The hundreds of newly identified rectangular and square complexes show highly standardized formats and were probably the earliest material expressions of basic concepts of Mesoamerican calendars and a number system.

“These cultural centers showed remarkable regularity in sizes and orientation along cardinal directions and were a landscape manifestation of the essential concepts of the Maya calendars and number system,” said study co-author Timothy Beach, a professor in the Department of Geography and the Environment at UT Austin. “Mesoamerican belief and knowledge systems are apparent in the landscapes they terraformed.”

Tuesday, November 2, 2021

Department of Energy to Provide $10 Million for Climate and Earth System Modeling Research

Today, the U.S. Department of Energy  announced plans to provide $10 million for new grants to universities, other academic institutions, non-profit organizations, for profit organizations, and other federal agencies within the area of Earth and environmental systems modeling research. Grants will focus on two related areas of research: further development of DOE’s flagship Energy Exascale Earth System Model (E3SM), with a particular emphasis on improving the accuracy of low level cloud representations; and studies that improve the predictive understanding of the climate variability, water cycle and related hydrological extremes.

Specific topics solicited in modeling research vary from year to year to enhance and take advantage of new modeling capabilities and emerging challenges facing the community. For this Funding Opportunity Announcement, grants will be strongly encouraged to emphasize high resolution, process-level, scientific understanding that advances or leverages E3SM’s current capability such as the Simple Cloud-Resolving E3SM Atmosphere Model (SCREAM) and the innovative use of a hierarchy of models, multi-models, machine learning, and metrics to reduce prediction uncertainty.

“Climate prediction research has evolved to become a national imperative, given that the trend towards increasing climate-induced risks to people, property, and infrastructure requires concerted action and climate solutions,” said Sharlene Weatherwax, DOE Associate Director for Biological and Environmental Research. “These grants will ensure a strengthened science base for making more accurate predictions of climate change that must be well understood before making informed decisions.”

The Department anticipates that $10 million will be available for this program in Fiscal Year 2022. Funding is to be awarded competitively, on the basis of peer review, and is expected to be in the form of three-year grants with total award amounts ranging from $600,000 to $900,000.

More information on the Office of Biological and Environmental Research (BER) can be found here. More information on the BER Earth and Environmental System Modeling program can be found here.

Source/Credit: U.S. Department of Energy

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Quadricep muscle contracts differently after ACL reconstruction

After an anterior cruciate ligament reconstruction surgery, it’s common to experience quadriceps weakness, which was thought to be caused primarily by muscle atrophy, or shrinkage.

But researchers at the University of Michigan School of Kinesiology have found an additional cause, which could help clinicians design more effective rehabilitation programs.

They found that besides muscle loss, the quadricep muscle—specifically, the fibers within that muscle—contract differently. Taken together, these deficits result in a muscle that is weaker and behaves like that of someone much older.

“This is the first human-based paper that is focused on proving that muscle is not just smaller after injury, but it also contracts differently,” said Lindsey Lepley, assistant professor and corresponding author on the study. “This is a key new discovery that helps explain the persistent weakness that is so commonly observed.”

Lepley said her group follows the aging literature and that many of the factors that plague aged muscle also emerge after ACL injury.

“Generally our group has been saying that an ACL injury prematurely ages the limb—the joint itself often shows signs of arthritis within 10 years and the muscle also exhibits factors like aged muscle tissue,” Lepley said.

ACL is a common musculoskeletal injury, with about 300,000 occurring annually in the United States. Yearly treatment costs exceed $2 billion.

Scientists identify new antibody for COVID-19 and variants

Megan May/UNC Research
A research collaboration between scientists at Duke University and the University of North Carolina at Chapel Hill has identified and tested an antibody that limits the severity of infections from a variety of coronaviruses, including those that cause COVID-19 as well as the original SARS illness.

The antibody was identified by a team at the Duke Human Vaccine Institute and tested in animal models at UNC-Chapel Hill. Researchers published their findings Nov. 2 in the journal Science Translational Medicine.

“This antibody has the potential to be a therapeutic for the current epidemic,” said co-senior author Dr. Barton Haynes, director of DHVI. “It could also be available for future outbreaks, if or when other coronaviruses jump from their natural animal hosts to humans.”

Haynes and colleagues at DHVI isolated the antibody by analyzing the blood from a patient who had been infected with the original SARS-CoV-1 virus, which caused the SARS outbreak in the early 2000s, and from a current COVID-19 patient.

They identified more than 1,700 antibodies, which the immune system produces to bind at specific sites on specific viruses to block the pathogen from infecting cells. When viruses mutate, many binding sites are altered or eliminated, leaving antibodies ineffectual. But there are often sites on the virus that remain unchanged despite mutations. The researchers focused on antibodies that target these sites because of their potential to be highly effective across different lineages of a virus.

Study Sheds Light on the Evolution of Underground Microbes

Calcite, a mineral related to the presence of microorganisms, was recovered from a deep fracture in Swedish granite. Reiners and Drake used mineral-related biosignatures such as these to look for ancient habitable conditions deep inside the Earth.Henrik Drake/Linnaeus University

A new study sheds light on the evolutionary history of what might be the most elusive form of life on Earth: the deep biosphere – a hidden realm of microbes inhabiting the upper few kilometers of Earth's crust.

Calcite, a mineral related to the presence of microorganisms, was recovered from a deep fracture in Swedish granite. Reiners and Drake used mineral-related biosignatures such as these to look for ancient habitable conditions deep inside the Earth. Henrik Drake/Linnaeus University

Deep, dark fractures reaching far down into the oldest rocks on Earth may seem about as hospitable to life as outer space, but some estimates suggest that microbes dwelling deep in the Earth's crust account for the majority of microbial life. These underground lifeforms, which make up what's known as the deep biosphere, could account for as much as 20% of all biomass on Earth.

These ecosystems host microbial lineages that are of interest for understanding the origin and evolution of life on our planet but remain the least explored and understood ecosystems on Earth, according to the authors of a new study that takes a closer look at how deep habitats changed during Earth's tumultuous past.

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