Methane could be the first detectable indication of life beyond Earth

If life is abundant in the universe, atmospheric methane may be the first sign of life beyond Earth detectable by astronomers. Although nonbiological processes can generate methane, a new study by scientists at UC Santa Cruz establishes a set of circumstances in which a persuasive case could be made for biological activity as the source of methane in a rocky planet's atmosphere.

This is especially noteworthy because methane is one of the few potential signs of life, or "biosignatures," that could be readily detectable with the James Webb Space Telescope, which will begin observations later this year.

"Oxygen is often talked about as one of the best biosignatures, but it's probably going to be hard to detect with JWST," said Maggie Thompson, a graduate student in astronomy and astrophysics at UC Santa Cruz and lead author of the new study.

Despite some prior studies on methane biosignatures, there had not been an up-to-date, dedicated assessment of the planetary conditions needed for methane to be a good biosignature. "We wanted to provide a framework for interpreting observations, so if we see a rocky planet with methane, we know what other observations are needed for it to be a persuasive biosignature," Thompson said.

Published March 28 in Proceedings of the National Academy of Sciences, the study examines a variety of non-biological sources of methane and assesses their potential to maintain a methane-rich atmosphere. These include volcanoes; reactions in settings such as mid-ocean ridges, hydrothermal vents, and tectonic subduction zones; and comet or asteroid impacts.

The case for methane as a biosignature stems from its instability in the atmosphere. Because photochemical reactions destroy atmospheric methane, it must be steadily replenished to maintain high levels.

"If you detect a lot of methane on a rocky planet, you typically need a massive source to explain that," said coauthor Joshua Krissansen-Totton, a Sagan Fellow at UCSC. "We know biological activity creates large amounts of methane on Earth, and probably did on the early Earth as well because making methane is a fairly easy thing to do metabolically."

Nonbiological sources, however, would not be able to produce that much methane without also generating observable clues to its origins. Outgassing from volcanoes, for example, would add both methane and carbon monoxide to the atmosphere, while biological activity tends to readily consume carbon monoxide. The researchers found that nonbiological processes cannot easily produce habitable planet atmospheres rich in both methane and carbon dioxide and with little to no carbon monoxide.

The study emphasizes the need to consider the full planetary context in evaluating potential biosignatures. The researchers concluded that, for a rocky planet orbiting a sun-like star, atmospheric methane is more likely to be considered a strong indication of life if the atmosphere also has carbon dioxide, methane is more abundant than carbon monoxide, and extremely water-rich planetary compositions can be ruled out.

"One molecule is not going to give you the answer -- you have to take into account the planet's full context," Thompson said. "Methane is one piece of the puzzle, but to determine if there is life on a planet you have to consider its geochemistry, how it's interacting with its star, and the many processes that can affect a planet's atmosphere on geologic timescales."

The study considers a variety of possibilities for "false positives" and provides guidelines for assessing methane biosignatures.

"There are two things that could go wrong -- you could misinterpret something as a biosignature and get a false positive, or you could overlook something that's a real biosignature," Krissansen-Totton said. "With this paper, we wanted to develop a framework to help avoid both of those potential errors with methane."

He added that there is still a lot of work to be done to fully understand any future methane detections. "This study is focused on the most obvious false positives for methane as a biosignature," he said. "The atmospheres of rocky exoplanets are probably going to surprise us, and we will need to be cautious in our interpretations. Future work should try to anticipate and quantify more unusual mechanisms for nonbiological methane production."

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European earthworms reduce insect populations in North American forests

Earthworms introduced into northern North America have a negative impact on the insect fauna above ground. Soil ecologists found this impact for abundance as well as for biomass and species richness of insects. Their results indicate that changes in insect communities can have causes that have previously received little attention.

At least since the last ice age, about 10,000 years ago, there have been almost no earthworms in the northern part of North America. However, over the last few centuries, they have been introduced, probably through soil and plant transport from Europe. Since then, they have been dispersed and changed the soil significantly, with far-reaching consequences for the soil ecosystem. What impact these invaders have on the world above ground has, up to now, rarely been investigated.

The study was performed in a forest near Calgary in Canada, which has areas that are either inhabited or uninhabited by earthworms. Here, the researchers used insect vacuum samplers to capture aboveground insects and compared the catches. They discovered that the abundance, biomass, and species richness of insects in areas with invasive earthworms, and those areas without them differed significantly. Where earthworm biomass was highest, the number of insect individuals was reduced by 61 per cent, insect biomass by 27 per cent and species richness by 18 per cent.

Insect above ground affected by invasive earthworms underground

"We had expected that earthworms would have an impact on aboveground insects," says lead author Dr Malte Jochum from iDiv and Leipzig University. "Even so, I was surprised at how pronounced the effects were, and that not only the abundance but also biomass and species richness were affected."

The mechanisms by which the earthworms affect the insects are, however, still not clear. "It's possible that the earthworms eat the food and reduce the habitat of those aboveground insects, such as beetles and fly larvae, which break down dead plant material," says Jochum. Since the majority of insects are herbivores, it could also be hypothesised that the observed decline in insects is due to changes in the vegetation caused by altered soil conditions. In this case, however, the researchers were unable to detect any significant alteration in the number of plant species or plant coverage. "Still, this doesn't rule out the influence of the plants," says Jochum. However, the data on species composition and other functional characteristics of the plant communities have yet to be evaluated.

The increase in predatory insect species and spiders was also striking. These seem to be benefiting from the changes.

Underestimated causes for biodiversity loss to be considered in conservation

"Up to now, only a few causes have been used to explain global changes in insect populations; mostly alterations in habitats above the ground," says senior author Prof Nico Eisenhauer from iDiv and Leipzig University. "These new results show that biodiversity loss can also have other causes which have, so far, received little attention and that these should be taken into consideration when developing management and conservation strategies for biodiversity."

Introduced earthworm species are not only found in North America but on almost every continent. However, since there had been very few earthworms in northern North America for a very long time, the effect of these invaders is particularly pronounced. "For regions like Europe, where natural communities have always co-developed with earthworms, comparable negative effects due to new earthworm species are very unlikely," says Jochum. "Quite the opposite. Here they are important ecosystem engineers, which many important ecosystem functions depend on."

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Perseverance records the first ever sounds from Mars

NASA's Perseverance rover, which has been surveying the surface of Mars since February 2021, has for the first time recorded the acoustic environment of the Red Planet. An international team led by an academic at the University of Toulouse III -- Paul Sabatier and including scientists from the CNRS and ISAE-SUPAERO, carried out an analysis of these sounds, which were obtained using the SuperCam instrument built in France under the authority of the French space agency CNES. Their findings are published on 1st April 2022 in Nature.

For 50 years, interplanetary probes have returned thousands of striking images of the surface of Mars, but never a single sound. Now, NASA's Perseverance mission has put an end to this deafening silence by recording the first ever Martian sounds. The scientific team for the French-US SuperCam instrument installed on Perseverance was convinced that the study of the soundscape of Mars could advance our understanding of the planet. This scientific challenge led them to design a microphone dedicated to the exploration of Mars, at ISAE-SUPAERO in Toulouse, France.

Perseverance first recorded sounds from the Red Planet on February 19, 2021, the day after its arrival. These sounds fall within the human audible spectrum, between 20 Hz and 20 kHz. First of all, they reveal that Mars is quiet, in fact so quiet that on several occasions the scientists thought the microphone was no longer working. It is obvious that, apart from the wind, natural sound sources are rare.

In addition to this investigation, the scientists focused on the sounds generated by the rover itself, including the shock waves produced by the impact of the SuperCam laser on rocks, and flights by the Ingenuity helicopter. By studying the propagation on Mars of these sounds, whose behaviour is very well well understood on Earth, they were able to accurately characterise the acoustic properties of the Martian atmosphere.

The researchers show that the speed of sound is lower on Mars than on Earth: 240 m/s, as compared to 340 m/s on our planet. However, the most surprising thing is that it turns out that there are actually two speeds of sound on Mars, one for high-pitched sounds and one for low frequencies. Sound attenuation is greater on Mars than on Earth, especially for high frequencies, which, unlike low frequencies, are attenuated very quickly, even at short distances. All these various factors would make it difficult for two people standing only five metres apart to have a conversation. They are due to the composition of the Martian atmosphere (96% CO2, compared to 0.04% on Earth) and the very low atmospheric surface pressure (170 times lower than on Earth).

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Mammals put brawn before brains to survive post-dinosaur world

Prehistoric mammals bulked up, rather than develop bigger brains, to boost their survival chances once dinosaurs had become extinct, research suggests.

For the first 10 million years after dinosaurs died out, mammals prioritised boosting their body size to adapt to radical shifts in the make-up of Earth's animal kingdom, researchers say.

Their findings show that the size of mammals' brains, compared with their body weight, decreased following a catastrophic asteroid impact 66 million years ago that ended the reign of dinosaurs. It had been widely thought that mammals' relative brain sizes generally increased over time in the wake of the wipeout.

While much is known about the evolution of the brains of modern-day mammals, it has been -- until now -- unclear how they developed in the first few million years following the mass extinction.

A team from the University of Edinburgh has shed light on the mystery by performing CT scans on newly discovered fossils from the 10-million-year period after the extinction, called the Paleocene.

Their findings reveal that the relative brain sizes of mammals at first decreased because their body size increased at a much faster rate. Results of scans also suggest the animals relied heavily on their sense of smell, and that their vision and other senses were less well developed. This suggests it was initially more important to be big than highly intelligent in order to survive in the post-dinosaur era, the team says.

Around 10 million years later, early members of modern mammal groups such as primates began to develop larger brains and a more complex range of senses and motor skills. This would have improved their survival chances at a time when competition for resources was far greater, the team says.

The study, published in the journal Science, was supported by Marie Skłodowska-Curie Actions, European Research Council, Leverhulme Trust and National Science Foundation. It also involved New Mexico Museum of Natural History and Science in the US and several international institutions.

The idea that big brains are always better to invade new environments or survive extinctions is misleading, according to the research team.

Lead researcher Dr Ornella Bertrand, of the University of Edinburgh's School of GeoSciences, says: "Large brains are expensive to maintain and, if not necessary to acquire resources, would have probably been detrimental for the survival of early placental mammals in the chaos and upheaval after the asteroid impact."

Because today's mammals are so intelligent, it is easy to assume that big brains helped our ancestors outlast the dinosaurs and survive extinction -- but that was not so, the team says.

Senior author Professor Steve Brusatte, also based at the University of Edinburgh, says: "The mammals that usurped the dinosaurs were fairly dim-witted, and only millions of years later did many types of mammals develop bigger brains as they were competing with each other to form new ecosystems."

The badlands of northwestern New Mexico are among the few places where scientists can find complete skulls and skeletons of the mammals that lived immediately after the mass extinction of dinosaurs.

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Deserts 'breathe' water vapor, study shows

Deserts may seem lifeless and inert, but they are very much alive. Sand dunes, in particular, grow and move -- and according to a decades long research project, they also breathe humid air.

The findings show for the first time how water vapor penetrates powders and grains, and could have wide-ranging applications far beyond the desert -- in pharmaceutical research, agriculture and food processing, as well as planetary exploration.

The team's paper published in the Journal of Geophysical Research-Earth Surface.

Wanting to measure matter with greater sensitivity, lead author Michel Louge, professor of mechanical and aerospace engineering at Cornell University, developed a new form of instrumentation called capacitance probes, which use multiple sensors to record everything from solid concentration to velocity to water content, all with unprecedented spatial resolution.

In the early 2000s, Louge began collaborating with Ahmed Ould el-Moctar from University of Nantes, France, to use the probes to study the moisture content in sand dunes to better understand the process by which agricultural lands turn to desert -- an interest that has only become more urgent with the rise of global climate change.

The probe eventually revealed just how porous sand is, with a tiny amount of air seeping through it. Previous research hinted this type of seepage existed in sand dunes, but no one had been able to prove it until now.

"The wind flows over the dune and as a result creates imbalances in the local pressure, which literally forces air to go into the sand and out of the sand. So, the sand is breathing, like an organism breathes," Louge said.

That "breathing" is what allows microbes to persist deep inside hyper-arid sand dunes, despite the high temperature. For much of the last decade, Louge has been collaborating with Anthony Hay, associate professor of microbiology at Cornell, to study how microbes can help stabilize the dunes and prevent them from encroaching into roads and infrastructure.

Louge and his team also determined that desert surfaces exchange less moisture with the atmosphere than expected, and that water evaporation from individual sand grains behaves like a slow chemical reaction.

The bulk of their data was gathered in 2011, but it still took Louge and his collaborators another decade to make sense of some of the findings, such as identifying disturbances at the surface level that force evanescent, or nonlinear, waves of humidity to propagate downward through the dunes very quickly.

The researchers anticipate their probe will have a number of applications -- from studying the way soils imbibe or drain water in agriculture, to calibrating satellite observations over deserts, to exploring extraterrestrial environments that may hold trace amounts of water. That wouldn't be the first time Louge's research made its way into space.

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Researchers generate the first complete, gapless sequence of a human genome

Scientists have published the first complete, gapless sequence of a human genome, two decades after the Human Genome Project produced the first draft human genome sequence. According to researchers, having a complete, gap-free sequence of the roughly 3 billion bases (or "letters") in our DNA is critical for understanding the full spectrum of human genomic variation and for understanding the genetic contributions to certain diseases. The work was done by the Telomere to Telomere (T2T) consortium, which included leadership from researchers at the National Human Genome Research Institute (NHGRI), part of the National Institutes of Health; University of California, Santa Cruz; and University of Washington, Seattle. NHGRI was the primary funder of the study.

Analyses of the complete genome sequence will significantly add to our knowledge of chromosomes, including more accurate maps for five chromosome arms, which opens new lines of research. This helps answer basic biology questions about how chromosomes properly segregate and divide. The T2T consortium used the now-complete genome sequence as a reference to discover more than 2 million additional variants in the human genome. These studies provide more accurate information about the genomic variants within 622 medically relevant genes.

"Generating a truly complete human genome sequence represents an incredible scientific achievement, providing the first comprehensive view of our DNA blueprint," said Eric Green, M.D., Ph.D., director of NHGRI. "This foundational information will strengthen the many ongoing efforts to understand all the functional nuances of the human genome, which in turn will empower genetic studies of human disease."

The now-complete human genome sequence will be particularly valuable for studies that aim to establish comprehensive views of human genomic variation, or how people's DNA differs. Such insights are vital for understanding the genetic contributions to certain diseases and for using genome sequence as a routine part of clinical care in the future. Many research groups have already started using a pre-release version of the complete human genome sequence for their research.

The full sequencing builds upon the work of the Human Genome Project, which mapped about 92% of the genome, and research undertaken since then. Thousands of researchers have developed better laboratory tools, computational methods and strategic approaches to decipher the complex sequence. Six papers encompassing the completed sequence appear in Science, along with companion papers in several other journals.

That last 8% includes numerous genes and repetitive DNA and is comparable in size to an entire chromosome. Researchers generated the complete genome sequence using a special cell line that has two identical copies of each chromosome, unlike most human cells, which carry two slightly different copies. The researchers noted that most of the newly added DNA sequences were near the repetitive telomeres (long, trailing ends of each chromosome) and centromeres (dense middle sections of each chromosome).

"Ever since we had the first draft human genome sequence, determining the exact sequence of complex genomic regions has been challenging," said Evan Eichler, Ph.D., researcher at the University of Washington School of Medicine and T2T consortium co-chair. "I am thrilled that we got the job done. The complete blueprint is going to revolutionize the way we think about human genomic variation, disease and evolution."

The cost of sequencing a human genome using "short-read" technologies, which provide several hundred bases of DNA sequence at a time, is only a few hundred dollars, having fallen significantly since the end of the Human Genome Project. However, using these short-read methods alone still leaves some gaps in assembled genome sequences. The massive drop in DNA sequencing costs comes hand-in-hand with increased investments in new DNA sequencing technologies to generate longer DNA sequence reads without compromising the accuracy.

Over the past decade, two new DNA sequencing technologies emerged that produced much longer sequence reads. The Oxford Nanopore DNA sequencing method can read up to 1 million DNA letters in a single read with modest accuracy, while the PacBio HiFi DNA sequencing method can read about 20,000 letters with nearly perfect accuracy. Researchers in the T2T consortium used both DNA sequencing methods to generate the complete human genome sequence.

"Using long-read methods, we have made breakthroughs in our understanding of the most difficult, repeat-rich parts of the human genome," says Karen Miga, Ph.D., a co-chair of the T2T consortium whose research group at the University of California, Santa Cruz is funded by NHGRI. "This complete human genome sequence has already provided new insight into genome biology, and I look forward to the next decade of discoveries about these newly revealed regions."

According to consortium co-chair Adam Phillippy, Ph.D., whose research group at NHGRI led the finishing effort, sequencing a person's entire genome should get less expensive and more straightforward in the coming years.

"In the future, when someone has their genome sequenced, we will be able to identify all of the variants in their DNA and use that information to better guide their healthcare," Phillippy said. "Truly finishing the human genome sequence was like putting on a new pair of glasses. Now that we can clearly see everything, we are one step closer to understanding what it all means."

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When worlds collide: Studying impact craters to uncover the secrets of the solar system

While for humans the constants might be death and taxes, for planets the constants are gravity and collisions.

Brandon Johnson studies the latter, using information about impacts to understand the history and the composition of planets, moons, asteroids and meteorites throughout the solar system.

"Impact cratering is the most ubiquitous surface process shaping planetary bodies," Johnson said. "Craters are found on almost every solid body we've ever seen. They are a major driver of change in planetary bodies. They drive the evolution of planetary crusts. All the planets and asteroids were built from a series of impacts. Studying impacts can help us determine the composition and structure of planets."

As an associate professor in the Department of Earth, Atmospheric, and Planetary Sciences in Purdue University's College of Science, Johnson has studied almost every major planetary body in the solar system. And the time scale of his research ranges from relatively recent impacts to nearly the beginning of the solar system itself.

Collecting clues about collisions helps Johnson reconstruct the environment in which the collisions took place, offering deep insights into how and when bodies formed. His research is helping humans explore the planetary bodies in the solar system with only physics, math and a computer. Space missions and laboratory analyses provide a constant supply of new data and questions to work on.

"Most meteorites contain chondrules -- small, previously molten, particles," Johnson said. "Essentially, by studying the formation of chondrules by impacts, we can better understand what was going on in the nascent solar system. For example, based on one impact, we were able to determine that Jupiter had already formed right around 5 million years after the first solar system solids, changing the timeline of our understanding of the solar system."

Johnson and his lab staff incorporate known factors about the composition and physics of planetary bodies into complex computer models, running the models through a range of conditions and comparing the results with observed phenomena. Analyzing movements and collisions can offer insights into the composition of asteroids and meteorites, helping scientists understand how elements like water and metal are distributed through a solar system. By studying impact craters and basins on places like Pluto, Venus and icy moons, and the mechanics of other processes occurring on Europa and asteroids like Psyche, his team can understand more about their interiors; whether they have molten cores and plate tectonics, for example, or whether they have liquid oceans.

His work doesn't just span the solar system. He studies impacts closer to home, too, including on Earth's own moon and terrestrial impacts that may have affected the way Earth's crust, atmosphere and biosphere evolved.

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Where we grow up influences our sense of direction

The streets, alleys, paths and parks of our childhood leave a strong mark on us, with heretofore unsuspected benefits. A research team led by scientists from the Laboratoire d'Informatique en Image et Systèmes d'Information (LIRIS, CNRS/INSA Lyon/Université Claude Bernard Lyon 1) and the Institute of Behavioural Neurosciences at University College London has found that where people grow up influences their sense of direction in adulthood. From a diverse set of origins, from rural to cities of varying complexity, they had uneven skills in terms of orienting themselves.

First, the scientists have found that, on average, people who grew up in the countryside have a better sense of direction than people who grew up in cities. This extent of this difference varies from country to country: very strong in Canada, the United States, Argentina and Saudi Arabia, much less so in Austria, France, India and Vietnam.

The research team then looked at the maps of the major cities in these countries to categorize them according to layout complexity. While cities like Chicago are arranged in grids, with most branch lines at a right angle, cities like Paris form a more heterogeneous network, with nearly every angle present. Thus, according to their results, growing up in a city with a complex topography confers a better sense of direction.

The research also shows that people generally orient themselves better when confronted with topographies close to those travelled during childhood: they are better at navigating great distances if they come from rural areas, and better on a grid plan if they grew up in a city "with right angles."

These results were achieved with Sea Hero Quest, a video game developed to study Alzheimer's disease. After having memorized the game map, players are set objectives at several levels. It can be difficult to recruit participants to an experiment, and even more so to reproduce an experiment under identical conditions, and video gaming is a way to address these problems. For this study, from Sea Hero Quest we compared the sense of direction of nearly 400,000 people in 38 countries around the world.

From Science Daily

Flowers' unseen colors can help ensure pollination, survival

You can't see it, but different substances in the petals of flowers create a "bulls-eye" for pollinating insects, according to a Clemson University scientist whose research sheds light on chemical changes in flowers which helps them respond to environmental changes, including climate change, that might threaten their survival.

Matthew H. Koski, an assistant professor of biological sciences in the Clemson College of Science, led a research team that studied the bright, yellow flowers of Argentina anserina -- a member of the rose family commonly known as silverweed -- to learn how pigments in the petals that are visible only in the ultraviolet spectrum play an integral part in the plant's plasticity; that is, its ability to quickly respond to a changing environment. The team also included Clemson researchers Lindsay M. Finnell, Elizabeth Leonard and Nishanth Tharayil.

The journal Evolution featured the findings on the cover of its March edition.

The researchers studied silverweed growing at different elevations in southwestern Colorado to better understand the roles of the various UV-absorbing chemicals in the plants' petals and how these chemicals work to aid in pollination and, thus, reproduction.

Koski explained that although humans cannot see the UV patterns on the flower's petals, many of its pollinators can.

"I've always been fascinated with how [color variation of flowers] arises and how it evolves and what factors drive the evolution of color variation," Koski said, "so I got interested in thinking about how we perceive color versus how the organisms that interact more frequently with flowers perceive color."

"Insects -- pollinators, for example -- see in the ultraviolet spectrum," he continued. "So, flowers that reflect or absorb ultraviolet wavelengths give (to pollinators) the perception of different colors that we can't see. I've been fascinated with uncovering what these UV signals might be doing functionally with respect to pollination. When I thought about the trait of interest in ultraviolet absorption, it is biochemistry. It's a biochemical trait that leads to different perceptions of UV absorption and reflectance."

Koski said a wide range of plants have concentrations of UV-absorbing chemicals at the base of the flower's petals, while the tips of the petals have more UV-reflecting chemicals. He said this creates an overall "bulls-eye" effect that guides insects in their search for pollen.

The team wanted to uncover more about how the plants adapt to thrive in different environments -- in this case, a difference in altitude of 1,000 meters. They found that flowers at different altitudes adapt to their environments by producing differing amounts of UV-blocking or UV-absorbing chemicals.

"At higher elevations, there are always more UV-absorbing compounds or larger spatial area of UV absorption on the petals, compared to the low-elevation populations," Koski said.

The researchers said this demonstrates the plant's plasticity, which Koski defined as how differing traits arise in the same organisms under different environmental conditions. This is a critical step in understanding how organisms adapt to survive change.

"What's important about plasticity is, when we think about climate change and global change, plasticity is one mechanism by which natural populations can respond really rapidly to changing climates and persist under those climates," he said. "The process of evolution, where you're getting changes in the genetic code over time, is thought to proceed more slowly than just responding plastically to environmental change."

Koski said that one question raised by the research is whether plastic responses to environmental situations are adaptive. Do they offer any advantage to an organism, or are they changes in how a trait develops because of the environment without impacting plant fitness?

"One thing this study found is that the plastic change in UV pigmentation benefited the plant, especially the ones at high elevations because increases in ultraviolet absorption on the petals resulted in increased pollen viability," he explained.

Koski went on to say the research will help scientists better understand how organisms respond to environmental changes and even predict if or how well some organisms would be able to survive rapid environmental change, such as from global climate change. The research could also be important for agriculture, he said, because some of the same UV-sensitive pigments at work in silverweed are also present in commercial crops such as mustard and sunflowers.

"It's interesting to think about if abiotic factors like UV or temperature are shifting the expression of these traits, how is that going to impact how pollinators view the flowers, and how's that going to affect things like yield and seed production in crops, for example," Koski said.

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Good hydration may reduce long-term risks for heart failure

Staying well-hydrated may be associated with a reduced risk for developing heart failure, according to researchers at the National Institutes of Health. Their findings, which appear in the European Heart Journal, suggest that consuming sufficient amounts of fluids throughout life not only supports essential body functioning but may also reduce the risk of severe heart problems in the future.

Heart failure, a chronic condition that develops when the heart does not pump enough blood for the body's needs, affects more than 6.2 million Americans, a little more than 2% of the population. It is also more common among adults ages 65 and older.

"Similar to reducing salt intake, drinking enough water and staying hydrated are ways to support our hearts and may help reduce long-term risks for heart disease," said Natalia Dmitrieva, Ph.D., the lead study author and a researcher in the Laboratory of Cardiovascular Regenerative Medicine at the National Heart, Lung, and Blood Institute (NHLBI), part of NIH.

After conducting preclinical research that suggested connections between dehydration and cardiac fibrosis, a hardening of the heart muscles, Dmitrieva and researchers looked for similar associations in large-scale population studies. To start, they analyzed data from more than 15,000 adults, ages 45-66, who enrolled in the Atherosclerosis Risk in Communities (ARIC) study between 1987-1989 and shared information from medical visits over a 25-year period.

In selecting participants for their retrospective review, the scientists focused on those whose hydration levels were within a normal range and who did not have diabetes, obesity, or heart failure at the start of the study. Approximately 11,814 adults were included in the final analysis, and, of those, the researchers found 1,366 (11.56%) later developed heart failure.

To assess potential links with hydration, the team assessed the hydration status of the participants using several clinical measures. Looking at levels of serum sodium, which increases as the body's fluid levels decrease, was especially useful in helping to identify participants with an increased risk for developing heart failure. It also helped identify older adults with an increased risk for developing both heart failure and left ventricular hypertrophy, an enlargement and thickening of the heart.

For example, adults with serum sodium levels starting at 143 milliequivalents per liter (mEq/L) -- a normal range is 135-146 mEq/L -- in midlife had a 39% associated increased risk for developing heart failure compared to adults with lower levels. And for every 1 mEq/L increase in serum sodium within the normal range of 135-146 mEq/L, the likelihood of a participant developing heart failure increased by 5%.

In a cohort of about 5,000 adults ages 70-90, those with serum sodium levels of 142.5-143 mEq/L at middle age were 62% more likely to develop left ventricular hypertrophy. Serum sodium levels starting at 143 mEq/L correlated with a 102% increased risk for left ventricular hypertrophy and a 54% increased risk for heart failure.

Based on these data, the authors conclude serum sodium levels above 142 mEq/L in middle age are associated with increased risks for developing left ventricular hypertrophy and heart failure later in life.

A randomized, controlled trial will be necessary to confirm these preliminary findings, the researchers said. However, these early associations suggest good hydration may help prevent or slow the progression of changes within the heart that can lead to heart failure.

"Serum sodium and fluid intake can easily be assessed in clinical exams and help doctors identify patients who may benefit from learning about ways to stay hydrated," said Manfred Boehm, M.D., who leads the Laboratory of Cardiovascular Regenerative Medicine.

Fluids are essential for a range of bodily functions, including helping the heart pump blood efficiently, supporting blood vessel function, and orchestrating circulation. Yet many people take in far less than they need, the researchers said. While fluid guidelines vary based on the body's needs, the researchers recommended a daily fluid intake of 6-8 cups (1.5-2.1 liters) for women and 8-12 cups (2-3 liters) for men. The Centers for Disease Control and Prevention also provides tips to support healthy hydration.

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Record broken: Hubble spots farthest star ever seen

NASA's Hubble Space Telescope has established an extraordinary new benchmark: detecting the light of a star that existed within the first billion years after the universe's birth in the big bang -- the farthest individual star ever seen to date.

The find is a huge leap further back in time from the previous single-star record holder; detected by Hubble in 2018. That star existed when the universe was about 4 billion years old, or 30 percent of its current age, at a time that astronomers refer to as "redshift 1.5." Scientists use the word "redshift" because as the universe expands, light from distant objects is stretched or "shifted" to longer, redder wavelengths as it travels toward us.

The newly detected star is so far away that its light has taken 12.9 billion years to reach Earth, appearing to us as it did when the universe was only 7 percent of its current age, at redshift 6.2. The smallest objects previously seen at such a great distance are clusters of stars, embedded inside early galaxies.

"We almost didn't believe it at first, it was so much farther than the previous most-distant, highest redshift star," said astronomer Brian Welch of the Johns Hopkins University in Baltimore, lead author of the paper describing the discovery, which is published in the March 30 journal Nature. The discovery was made from data collected during Hubble's RELICS (Reionization Lensing Cluster Survey) program, led by co-author Dan Coe at the Space Telescope Science Institute (STScI), also in Baltimore.

"Normally at these distances, entire galaxies look like small smudges, with the light from millions of stars blending together," said Welch. "The galaxy hosting this star has been magnified and distorted by gravitational lensing into a long crescent that we named the Sunrise Arc."

After studying the galaxy in detail, Welch determined that one feature is an extremely magnified star that he called Earendel, which means "morning star" in Old English. The discovery holds promise for opening up an uncharted era of very early star formation.

"Earendel existed so long ago that it may not have had all the same raw materials as the stars around us today," Welch explained. "Studying Earendel will be a window into an era of the universe that we are unfamiliar with, but that led to everything we do know. It's like we've been reading a really interesting book, but we started with the second chapter, and now we will have a chance to see how it all got started," Welch said.

When Stars Align

The research team estimates that Earendel is at least 50 times the mass of our Sun and millions of times as bright, rivaling the most massive stars known. But even such a brilliant, very high-mass star would be impossible to see at such a great distance without the aid of natural magnification by a huge galaxy cluster, WHL0137-08, sitting between us and Earendel. The mass of the galaxy cluster warps the fabric of space, creating a powerful natural magnifying glass that distorts and greatly amplifies the light from distant objects behind it.

Thanks to the rare alignment with the magnifying galaxy cluster, the star Earendel appears directly on, or extremely close to, a ripple in the fabric of space. This ripple, which is defined in optics as a "caustic," provides maximum magnification and brightening. The effect is analogous to the rippled surface of a swimming pool creating patterns of bright light on the bottom of the pool on a sunny day. The ripples on the surface act as lenses and focus sunlight to maximum brightness on the pool floor.

This caustic causes the star Earendel to pop out from the general glow of its home galaxy. Its brightness is magnified a thousandfold or more. At this point, astronomers are not able to determine if Earendel is a binary star, though most massive stars have at least one smaller companion star.

Confirmation with Webb

Astronomers expect that Earendel will remain highly magnified for years to come. It will be observed by NASA's James Webb Space Telescope. Webb's high sensitivity to infrared light is needed to learn more about Earendel, because its light is stretched (redshifted) to longer infrared wavelengths due to the universe's expansion.

"With Webb we expect to confirm Earendel is indeed a star, as well as measure its brightness and temperature," Coe said. These details will narrow down its type and stage in the stellar lifecycle. "We also expect to find the Sunrise Arc galaxy is lacking in heavy elements that form in subsequent generations of stars. This would suggest Earendel is a rare, massive metal-poor star," Coe said.

Earendel's composition will be of great interest for astronomers, because it formed before the universe was filled with the heavy elements produced by successive generations of massive stars. If follow-up studies find that Earendel is only made up of primordial hydrogen and helium, it would be the first evidence for the legendary Population III stars, which are hypothesized to be the very first stars born after the big bang. While the probability is small, Welch admits it is enticing all the same.

"With Webb, we may see stars even farther than Earendel, which would be incredibly exciting," Welch said. "We'll go as far back as we can. I would love to see Webb break Earendel's distance record."

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Plastic bag bans may unintentionally drive other bag sales

When cities or counties institute plastic bag bans or fees, the idea is to reduce the amount of plastic headed to the landfill.

But a new analysis by a University of Georgia researcher finds these policies, while created with good intentions, may cause more plastic bags to be purchased in the communities where they are in place. The study was published earlier this year in the journal Environmental and Resource Economics.

That's because while plastic grocery bags are viewed as a single-use item, they often find a second use as liners for small trash cans. When these shopping bags are taxed or taken away, people look for alternatives -- which means they buy small plastic garbage bags.

"We know there is a demand for using plastic bags, and we know, if these policies go into effect, some bags will disappear or will become more costly to get," said Yu-Kai Huang, a postdoctoral researcher at the UGA Warnell School of Forestry and Natural Resources. "So, we wanted to see the effectiveness of this policy in reducing bag usage overall."

Previous studies have looked at the effect of bag bans on plastic consumption, but not the combined effects of fees or a bag ban. An environmental economist, Huang used a new way to calculate the effect of either policy while also accounting for variables such as residents' income levels and an area's population density, both of which influence the amount of trash generated in a community.

Is banning plastic bags effective overall?

Keeping in mind the second life that plastic grocery bags take on in many homes, Huang and professor Richard Woodward of Texas A&M University measured plastic trash bag sales in counties with bans or fees in place, and compared them to other counties without such policies. The selected counties were far enough away from each other to account for shoppers who might cross into a neighboring county to avoid the policy.

The study found California communities with bag policies saw sales of 4-gallon trash bags increase by 55% to 75%, and sales of 8-gallon trash bags increase 87% to 110%. These results echo earlier studies that also showed increases in sales of smaller plastic trash bags.

But while sales of small garbage bags jumped after policies were implemented, sales of larger 13-gallon trash bags -- the size often found in kitchen trash cans -- remained relatively unchanged. This further underscored the double life of plastic grocery bags, Huang said.

"Carryout grocery bags were substituted for similar sizes of trash bags before implementing the regulations," he wrote in the paper. "After the regulations came into effect, consumers' plastic bag demand switched from regulated plastic bags to unregulated bags."

The unintended increase in trash bag sales could also be measured by weight. By purchasing 4-gallon trash bags, plastic consumption increased by between 30 and 135 pounds per store per month. The sales of 8-gallon trash bags created an additional 37 to 224 pounds of plastic per store per month.

But, Huang noted, bag bans or fees could make a dent in plastic waste among high-volume stores. The study found that if a store generated at least 326 carryout plastic bags a day -- about 9,769 per month -- the policy would end up sending less plastic to the landfill.

It's important for policymakers to understand the unintended consequences of plastic bag bans or fees before implementing them, Huang said. And, if residents are reusing bags for trash cans, it can also affect the overall use.

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Unravelling the mystery of parrot longevity

Parrots are famous for their remarkable cognitive abilities and exceptionally long lifespans. Now, a study led by Max Planck researchers has shown that one of these traits has likely been caused by the other. By examining 217 parrot species, the researchers revealed that species such as the scarlet macaw and sulphur-crested cockatoo have extremely long average lifespans, of up to 30 years, which are usually seen only in large birds. Further, they demonstrated a possible cause for these long lifespans: large relative brain size. The study is the first to show a link between brain size and lifespan in parrots, suggesting that increased cognitive ability may have helped parrots to navigate threats in their environment and to enjoy longer lives.

Despite the fact that parrots are well known for their long lives and complex cognition, with lifespans and relative brain size on par with primates, it remains unknown whether the two traits have influenced each other.

"The problem has been sourcing good quality data," says Simeon Smeele, a doctoral student at the Max Planck Institute of Animal Behavior (MPI-AB) and lead author on the study, published in Proceedings of the Royal Society B. Understanding what has driven parrot longevity is only possible by comparing living parrots. "Comparative life-history studies require large sample sizes to provide certainty, because many processes are a play at once and this creates a lot of variation," says Smeele.

To generate an adequate sample size, scientists from the MPI-AB and the Max Planck Institute for Evolutionary Anthropology (MPI-EvA) teamed up with Species360, which draws on animal records from zoos and aquaria. Together, they compiled data from over 130,000 individual parrots sourced from over 1000 zoos. This database allowed the team to gain the first reliable estimates of average life span of 217 parrot species -- representing over half of all known species.

The analysis revealed an astonishing diversity in life expectancy, ranging from an average of two years for the fig parrot up to an average of 30 years for the scarlet macaw. Other long-lived species include the sulphur crested cockatoo from Australia, which lives on average 25 years.

"Living an average of 30 years is extremely rare in birds of this size," says Smeele who worked closely with Lucy Aplin from MPI-AB and Mary Brooke McElreath from MPI-EvA on the study. "Some individuals have a maximum lifespan of over 80 years, which is a respectable age even for humans. These values are really spectacular if you consider that a human male weights about 100 times more."

Next, the team employed a large-scale comparative analysis to determine whether or not parrots' renowned cognitive abilities had any influence on their longevity. They examined two hypotheses: First, that having relatively larger brains enable longer lifespans. In other words, smarter birds can better solve problems in the wild, thus enjoying longer lives. Second, that relatively larger brains take longer to grow, and therefore require longer lifespans. For each species, they collected data on relative brain size, as well as average body weight and developmental variables.

They then combined the data and ran models for each hypothesis, looking at which model best explained the data. Their results provide the first support that increased brain size has enabled longer lifespans in parrots. Because brain size relative to body size can be an indicator for intelligence, the findings suggest that the parrots with relatively large brains had cognitive capabilities that allowed them to solve problems in the wild that could otherwise kill them, and this intelligence enabled them to live longer lives.

"This supports the idea that in general larger brains make species more flexible and allow them to live longer," says Smeele. "For example, if they run out of their favourite food, they could learn to find something new and thus survive."

The scientists are surprised that factors such as diet, or the greater developmental time required to develop larger brains, did not lead to longer average lifespans. "We would have expected the developmental path to play a more important role because in primates it is this developmental cost that explains the link between brain size and longevity," says Smeele.

In the future, the team plan to explore if sociality and cultural learning in parrots might have also contributed to long lifespans. Says Smeele: "Large-brained birds might spend more time socially learning foraging techniques that have been around for multiple generations. This increased learning period could potentially also explain the longer life spans, as it takes more time but also makes the foraging repertoire more adaptive."

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Spiders use webs to extend their hearing

Everyone knows that humans and most other vertebrate species hear using eardrums that turn soundwave pressure into signals for our brains. But what about smaller animals like insects and arthropods? Can they detect sounds? And if so, how?

Distinguished Professor Ron Miles, a Department of Mechanical Engineering faculty member at Binghamton University's Thomas J. Watson College of Engineering and Applied Science, has been exploring that question for more than three decades, in a quest to revolutionize microphone technology.

A newly published study of orb-weaving spiders -- the species featured in the classic children's book "Charlotte's Web" -- has yielded some extraordinary results: The spiders are using their webs as extended auditory arrays to capture sounds, possibly giving spiders advanced warning of incoming prey or predators.

The paper, "Outsourced Hearing in an Orb-Weaving Spider that Uses its Web as an Auditory Sensor," published March 29 in the Proceedings of the National Academy of Sciences, provides the first evidence that a spider can outsource hearing to its web.

It is well-known that spiders respond when something vibrates their webs, such as potential prey. In these new experiments, researchers for the first time show that spiders turned, crouched or flattened out in response to sounds in the air.

The study is the latest collaboration between Miles and Ron Hoy, a biology professor from Cornell, and it has implications for designing extremely sensitive bio-inspired microphones for use in hearing aids and cell phones.

Jian Zhou, who earned his PhD in Miles' lab and is doing postdoctoral research at the Argonne National Laboratory, and Junpeng Lai, a current PhD student in Miles' lab, are co-first authors. Miles, Hoy and Associate Professor Carol I. Miles from the Harpur College of Arts and Sciences' Department of Biological Sciences at Binghamton are also authors for this study. Grants from the National Institutes of Health to Ron Miles funded the research.

A single strand of spider silk is so thin and sensitive that it can detect the movement of vibrating air particles that make up a soundwave, which is different from how eardrums work. Ron Miles' previous research has led to the invention of novel microphone designs that are based on hearing in insects.

"The spider is really a natural demonstration that this is a viable way to sense sound using viscous forces in the air on thin fibers," he said. "If it works in nature, maybe we should have a closer look at it."

Spiders can detect miniscule movements and vibrations through sensory organs on their tarsal claws at the tips of their legs, which they use to grasp their webs. Orb-weaver spiders are known to make large webs, creating a kind of acoustic antennae with a sound-sensitive surface area that is up to 10,000 times greater than the spider itself.

In the study, the researchers used Binghamton University's anechoic chamber, a completely soundproof room under the Innovative Technologies Complex. Collecting orb-weavers from windows around campus, they had the spiders spin a web inside a rectangular frame so they could position it where they wanted.

The team began by using pure tone sound 3 meters away at different sound levels to see if the spiders responded or not. Surprisingly, they found spiders can respond to sound levels as low as 68 decibels. For louder sound, they found even more types of behaviors.

They then placed the sound source at a 45-degree angle, to see if the spiders behaved differently. They found that not only are the spiders localizing the sound source, but they can tell the sound incoming direction with 100% accuracy.

To better understand the spider-hearing mechanism, the researchers used laser vibrometry and measured over one thousand locations on a natural spider web, with the spider sitting in the center under the sound field. The result showed that the web moves with sound almost at maximum physical efficiency across an ultra-wide frequency range.

"Of course, the real question is, if the web is moving like that, does the spider hear using it?" Miles said. "That's a hard question to answer."

Lai added: "There could even be a hidden ear within the spider body that we don't know about."

So the team placed a mini-speaker 5 centimeters away from the center of the web where the spider sits, and 2 millimeters away from the web plane -- close but not touching the web. This allows the sound to travel to the spider both through air and through the web. The researchers found that the soundwave from the mini-speaker died out significantly as it traveled through the air, but it propagated readily through the web with little attenuation. The sound level was still at around 68 decibels when it reached the spider. The behavior data showed that four out of 12 spiders responded to this web-borne signal.

Those reactions proved that the spiders could hear through the webs, and Lai was thrilled when that happened: "I've been working on this research for five years. That's a long time, and it's great to see all these efforts will become something that everybody can read."

The researchers also found that, by crouching and stretching, spiders may be changing the tension of the silk strands, thereby tuning them to pick up different frequencies. By using this external structure to hear, the spider could be able to customize it to hear different sorts of sounds.

Future experiments may investigate how spiders make use of the sound they can detect using their web. Additionally, the team would like to test whether other types of web-weaving spiders also use their silk to outsource their hearing.

"It's reasonable to guess that a similar spider on a similar web would respond in a similar way," Ron Miles said. "But we can't draw any conclusions about that, since we tested a certain kind of spider that happens to be pretty common."

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Smells like ancient society: Scientists find ways to study and reconstruct past scents

In a new call for action paper published in Nature Human Behaviour, researchers from the Max Planck Institute for the Science of Human History in Jena, Germany, discuss the importance of scent in human history and address how and why experts might investigate smells from the past.

In recent years, millions of people worldwide have suffered the loss of smell due to COVID-19. Even those who have avoided infection with the new coronavirus experience the world of scent differently now due to the very masks that provide protection from the virus. This loss of olfaction has highlighted the important role of smell in how we perceive and navigate the world, and underscored the connections between olfaction and mental and physical health.

Scent has always been an integral component of the human experience, but up until now, the past has remained largely odorless. Most scents come from organic substances that decay quickly, leaving little for archaeologists to investigate thousands of years later. Now a team of researchers from the MPI for the Science of Human History is looking for new ways to bring the smellscapes of the past back to life and using smell to study past experience, behaviour, and society.

"Tracking scent in the deep past is not a simple task," says Barbara Huber, the lead author of the paper, "but the fact that history records expeditions of discovery, wars, and long-distance exchange to acquire materials with strong olfactory properties -- like incense and spices -- reveals how significant scent has been for human kind."

Understanding the sensorial dimension of human history and the use of odorous and aromatic substances can contribute knowledge about many aspects of the past -- including ritual, perfumery, hygiene, cuisine, trade and commerce. But because scent is part of how we experience, understand and navigate the world, ancient scents can also provide insight into more general aspects of the past, from social hierarchy and social practices to group identity.

"Scent is a powerful and underappreciated aspect of human experience," notes Professor Nicole Boivin, senior author of the study and Director of the Department of Archaeology at the MPI Science of Human History "Smells reach our brain fairly directly and motivate us in critical ways -- whether to avoid danger, identify something that is good for us, or remember something from our past, for example."

"Using only traces of scented substances preserved in archaeological artefacts and features," adds Huber, "novel methods are revealing the powerful odours that were a cardinal feature of ancient lived realities, and that shaped human action, thoughts, emotions and memories."

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Hundreds of new mammal species waiting to be found, study says

At least hundreds of so-far unidentified species of mammals are hiding in plain sight around the world, a new study suggests.

Researchers found that most of these hidden mammals are small bodied, many of them bats, rodents, shrews, and moles.

These unknown mammals are hidden in plain sight partly because most are small and look so much like known animals that biologists have not been able to recognize they are actually a different species, said study co-author Bryan Carstens, a professor of evolution, ecology and organismal biology at The Ohio State University.

"Small, subtle differences in appearance are harder to notice when you're looking at a tiny animal that weighs 10 grams than when you're looking at something that is human-sized," Carstens said.

"You can't tell they are different species unless you do a genetic analysis."

The study was published today (March 28, 2022) in the Proceedings of the National Academy of Sciences.

The team, led by Ohio State graduate student Danielle Parsons, used a supercomputer and machine-learning techniques to analyze millions of publicly available gene sequences from 4,310 mammal species, as well as data on where the animals live, their environment, life history and other relevant information.

This allowed them to build a predictive model to identify the taxa of mammals that are likely to contain hidden species.

"Based on our analysis, a conservative estimate would be that there are hundreds of species of mammals worldwide that have yet to be identified," Carstens said.

That finding, in itself, would not be surprising to biologists, he said. Only an estimated 1 to 10% of Earth's species have been formally described by researchers.

"What we did that was new was predict where these new species are most likely to be found," Carstens said.

Results showed unidentified species are most likely to be found in the families of small-bodied animals, such as bats and rodents.

The researchers' model also predicted hidden species would most likely be found in species that have wider geographic ranges with higher variability in temperature and precipitation.

Many of the hidden species are also likely to occur in tropical rain forests, which is not surprising because that's where most mammal species occur.

But many unidentified species are also likely living here in the United States, Carstens said. His lab has identified some of them. For example, in 2018, Carstens and his then-graduate student Ariadna Morales published a paper showing that the little brown bat, found in much of North America, is actually five different species.

That study also showed a key reason why it is important to identify new species. One of the newly delimited bats had a very narrow range where it lived, just around the Great Basin in Nevada -- making its protection especially critical.

"That knowledge is important to people who are doing conservation work. We can't protect a species if we don't know that it exists. As soon as we name something as a species, that matters in a lot of legal and other ways," Carstens said.

Based on the results of this study, Carstens estimates that somewhere near 80% of mammal species worldwide have been identified.

"The shocking thing is that mammals are very well described compared to beetles or ants or other types of animals," he said.

"We know a lot more about mammals than many other animals because they tend to be larger and are more closely related to humans, which makes them more interesting to us."

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Ancient helium leaking from core offers clues to Earth's formation

Helium-3, a rare isotope of helium gas, is leaking out of Earth's core, a new study reports. Because almost all helium-3 is from the Big Bang, the gas leak adds evidence that Earth formed inside a solar nebula, which has long been debated.

Helium-3 has been measured at Earth's surface in relatively small quantities. But scientists did not know how much was leaking from the Earth's core, as opposed to its middle layers, called the mantle.

The new study pins down the core as a major source of helium-3 for the Earth. Some natural processes can generate helium-3, such as the radioactive decay of tritium, but helium-3 is made primarily in solar nebulae -- massive, spinning clouds of gas and dust like the one that gave rise to our Solar System. Because helium is one of the earliest elements produced in the universe, most helium-3 can be traced back to the Big Bang.

As a planet grows, it accumulates material from its surroundings, so its composition reflects the environment in which it formed. To get high concentrations of helium-3 deep in the core, Earth would have had to form inside a thriving solar nebula, not on its fringes or during its waning phase.

The new research adds further clues to the mystery surrounding Earth's formation, lending additional evidence to the theory that our planet formed inside the solar nebula.

The study was published in the AGU journal Geochemistry, Geophysics, Geosystems, which publishes research on the chemistry, physics, geology and biology of Earth and planetary processes.

About 2,000 grams of helium-3 leak out of the Earth every year, "about enough to fill a balloon the size of your desk," said lead study author Peter Olson, a geophysicist at the University of New Mexico. "It's a wonder of nature, and a clue for the history of the Earth, that there's still a significant amount of this isotope in the interior of the Earth."

The researchers modeled helium during two key stages of Earth's history: early formation, when the planet was accumulating helium, and following the formation of the Moon, after which helium was lost. Evidence suggests an object one-third the size of the Earth hit the planet early in its history, around 4 billion years ago and that impact would have re-melted the Earth's crust, allowing much of the helium to escape. The gas continues escaping to this day.

Using the modern helium-3 leak rate along with models of helium isotope behavior, the researchers estimated there are between 10 teragrams (1013 grams) to a petagram (1015 grams) of helium-3 in the core -- a vast quantity that Olson said points to Earth's formation inside the solar nebula, where high concentrations of the gas would have allowed it to build up deep in the planet.

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New nasal spray treats Delta variant infection in mice, indicating broad spectrum results

Researchers have shown a new compound delivered in a nasal spray is highly effective in preventing and treating COVID-19 caused by the Delta variant in mice.

The researchers, including at UBC, Université de Sherbrooke, and Cornell University, believe this is the first treatment of its kind proven to be effective against all COVID-19 variants of concern reported to date, including alpha, beta, gamma and delta. Published today in Nature, the research opens the door to developing a therapeutic spray for humans.

Variants of concern, including the recent Omicron variants, have reduced vaccine effectiveness, but senior author Dr. François Jean, associate professor in the UBC department of microbiology and immunology, says early, still unpublished results from his team show promise that N-0385 is also effective at blocking Omicron variant infections in human lung cells. "Our unpublished results represent encouraging findings with the current rapid propagation of Omicron BA.2 around the world."

"Unfortunately, with another wave of an Omicron variant hitting the U.K., Europe, and China and our knowledge of how these waves occur, this may be what we see in Canada in the near future. Once approved, this compound could be used in combination with already available drugs that inhibit the virus' replication, to provide a stronger defense against COVID-19 variants of concern," says Dr. Jean, founder of FINDER, the state-of-the-art level three biocontainment facility where the work on SARS-CoV-2 variants was conducted.

The specially designed compound, named N-0385, blocks a particular human enzyme's activity, used by the virus to infect a host cell. The small molecule was developed by Drs. Richard Leduc, Éric Marsault, Pierre-Luc Boudreault and their team at Université de Sherbrooke. UBC researchers tested four variants, including Delta, in human lung cells and organoids, tissue cultures that can mimic the organ they're taken from, and found that N-0385 inhibits infection, with no evidence of toxicity. "The compound is unique because it blocks entry at the cell surface, without having to get into the cell, which prevents it from causing any detectable cell damage. As well, it's highly potent, in that it needs only a tiny amount to work very effectively," says co-author Dr. Andrea Olmstead (she/her), research associate in the department of microbiology and immunology.

In a preprint, the researchers at Cornell University led by Associate Professor Hector Aguilar-Carreno showed that genetically engineered mice infected with the virus causing COVID-19 and given a daily dose of the compound in a nasal spray for four days. All ten of the treated mice survived infection, compared with only 20 per cent of the untreated mice.

In the newly published paper, N-0385 was tested against the Delta variant, and was found to not only help with prevention of COVID-19, but also treatment 12 hours after infection, including with infection-related weight loss, and levels of the virus in the mice lungs, compared with controls.

The enzyme which N-0385 targets is present in nasal cells, where the virus tends to enter, making a nasal spray the most practical and effective way to administer the compound. In addition, no mutations relating to the virus which causes COVID-19 have been found in this enzyme's mechanism so far, as has occurred with other enzymes and COVID-19 variants, making it a useful target for defense against future strains of the virus, says Dr. Jean.

The compound has the potential to be used as a broad-spectrum treatment against other viruses which use the same mechanism, Dr. Jean says, including influenza viruses such as influenza A, H1N1, and influenza C. "Even not knowing what you've been infected with during flu season, you could potentially be prescribed a nasal spray to treat coronaviruses and the flu."

However, the spray should be used in combination with other drugs already on the market, he says, as the compound is an entry inhibitor, blocking entry of the virus to cells while other drugs reduce replication. "The big picture is, there are multiple steps in the life cycle of a virus. The first step is entering a cell to pass on genetic material, then it goes on to replicate. So you would use both drugs: N-0385 could block most of the virus' entry, making less work for the replicator drug."

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Mysterious death of carbon star plays out like six-ring circus

Scientists studying V Hydrae (V Hya) have witnessed the star's mysterious death throes in unprecedented detail. Using the Atacama Large Millimeter/submillimeter Array (ALMA) and data from the Hubble Space Telescope (HST), the team discovered six slowly-expanding rings and two hourglass-shaped structures caused by the high-speed ejection of matter out into space. The results of the study are published in The Astrophysical Journal.

V Hya is a carbon-rich asymptotic giant branch (AGB) star located approximately 1,300 light-years from Earth in the constellation Hydra. More than 90-percent of stars with a mass equal to or greater than the Sun evolve into AGB stars as the fuel required to power nuclear processes is stripped away. Among these millions of stars, V Hya has been of particular interest to scientists due to its so-far unique behaviors and features, including extreme-scale plasma eruptions that happen roughly every 8.5 years and the presence of a nearly invisible companion star that contributes to V Hya's explosive behavior.

"Our study dramatically confirms that the traditional model of how AGB stars die -- through the mass ejection of fuel via a slow, relatively steady, spherical wind over 100,000 years or more -- is at best, incomplete, or at worst, incorrect," said Raghvendra Sahai, an astronomer at NASA's Jet Propulsion Laboratory, and the principal researcher on the study. "It is very likely that a close stellar or substellar companion plays a significant role in their deaths, and understanding the physics of binary interactions is both important across astrophysics and one of its greatest challenges. In the case of V Hya, the combination of a nearby and a hypothetical distant companion star is responsible, at least to some degree, for the presence of its six rings, and the high-speed outflows that are causing the star's miraculous death."

Mark Morris, an astronomer at UCLA and a co-author on the research added, "V Hydra has been caught in the process of shedding its atmosphere -- ultimately most of its mass -- which is something that most late-stage red giant stars do. Much to our surprise, we have found that the matter, in this case, is being expelled as a series of outflowing rings. This is the first and only time that anybody has seen that the gas being ejected from an AGB star can be flowing out in the form of a series of expanding 'smoke rings.'"

The six rings have expanded outward from V Hya over the course of roughly 2,100 years, adding matter to and driving the growth of a high-density flared and warped disk-like structure around the star. The team has dubbed this structure the DUDE, or Disk Undergoing Dynamical Expansion.

"The end state of stellar evolution -- when stars undergo the transition from being red giants to ending up as white dwarf stellar remnants -- is a complex process that is not well understood," said Morris. "The discovery that this process can involve the ejections of rings of gas, simultaneous with the production of high-speed, intermittent jets of material, brings a new and fascinating wrinkle to our exploration of how stars die."

Sahai added, "V Hya is in the brief but critical transition phase that does not last very long, and it is difficult to find stars in this phase, or rather 'catch them in the act. We got lucky and were able to image all of the different mass-loss phenomena in V Hya to better understand how dying stars lose mass at the end of their lives."

In addition to a full set of expanding rings and a warped disk, V Hya's final act features two hourglass-shaped structures -- and an additional jet-like structure -- that are expanding at high speeds of more than half a million miles per hour (240 km/s). Large hourglass structures have been observed previously in planetary nebulae, including MyCn 18 -- also known as the Engraved Hourglass Nebula -- a young emission nebula located roughly 8,000 light-years from Earth in the southern constellation of Musca, and the more well-known Southern Crab Nebula, an emission nebula located roughly 7,000 light-years from Earth in the southern constellation Centaurus.

Sahai said, "We first observed the presence of very fast outflows in 1981. Then, in 2022, we found a jet-like flow consisting of compact plasma blobs ejected at high speeds from V Hya. And now, our discovery of wide-angle outflows in V Hya connects the dots, revealing how all these structures can be created during the evolutionary phase that this extra-luminous red giant star is now in."

Due to both the distance and the density of the dust surrounding the star, studying V Hya required a unique instrument with the power to clearly see matter that is both very far away and also difficult or impossible to detect with most optical telescopes. The team enlisted ALMA's Band 6 (1.23mm) and Band 7 (.85mm) receivers, which revealed the star's multiple rings and outflows in stark clarity.

"The processes taking place at the end stages of low mass stars, and during the AGB phase in particular, have long fascinated astronomers and have been challenging to understand," said Joe Pesce, an astronomer and NSF program officer for NRAO/ALMA. "The capabilities and resolution of ALMA are finally allowing us to witness these events with the extraordinary detail necessary to provide some answers and enhance our understanding of an event that happens to most of the stars in the Universe."

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Octopus-like tentacles help cancer cells invade the body

With help from the best tweezers in the world a team of researchers from the University of Copenhagen has shed new light on a fundamental mechanism in all living cells that helps them explore their surroundings and even invade tissue. Their discovery could have implications for research into cancer, neurological disorders and much else.

Using octopus-like tentacles, a cell pushes toward its target, a bacterium, like a predator tracking down its prey. The scene could be playing out in a nature programme. Instead the pursuit is being observed at the nano-scale through a microscope at the University of Copenhagen's Niels Bohr Institute. The microscope recording shows a human immune cell pursuing and then devouring a bacterium.

With their new study, a team of Danish researchers has added to the world's understanding of how cells use octopus-like tentacles called filopodia to move around in our bodies. This discovery about how cells move had never been addressed. The study is being published today in the journal, Nature Communications.

"While the cell doesn't have eyes or a sense of smell, its surface is equipped with ultra-slim filopodia that resemble entangled octopus tentacles. These filopodia help a cell move towards a bacterium, and at the same time, act as sensory feelers that identify the bacterium as a prey," explains Associate Professor Poul Martin Bendix, head of the laboratory for experimental biophysics at the Niels Bohr Institute.

The discovery is not that filopodia act as sensory devices -- which was already well established -- but rather about how they can rotate and behave mechanically, which helps a cell move, as when a cancer cell invades new tissue.

"Obviously, our results are of interest to cancer researchers. Cancer cells are noted for their being highly invasive. And, it is reasonable to believe that they are especially dependent on the efficacy of their filopodia, in terms of examining their surroundings and facilitating their spread. So, it's conceivable that by finding ways of inhibiting the filopodia of cancer cells, cancer growth can be stalled," explains Associate Professor Poul Martin Bendix.

For this reason, researchers from the Danish Cancer Society Research Center are a part of the team behind the discovery. Among other things, the cancer researchers are interested in whether switching off the production of certain proteins can inhibit the transport mechanisms which are important for the filopodia of cancer cells.

The cell's engine and cutting torch

According to Poul Martin Bendix, the mechanical function of filopodia can be compared to a rubber band. Untwisted, a rubber band has no power. But if you twist it, it contracts. This combination of twisting and contraction helps a cell move directionally and makes the filopodia very flexible.

"They're able to bend -- twist, if you will -- in a way that allows them to explore the entire space around the cell, and they can even penetrate tissues in their environment," says lead author, Natascha Leijnse.

The mechanism discovered by the Danish researchers appears to be found in all living cells. Besides cancer cells, it is also relevant to study the importance of filopodia in other types of cells, such as embryonic stem cells and brain cells, which are highly dependent on filopodia for their development.

Studying cells with the best tweezers in the world

The project involved interdisciplinary collaboration at the Niels Bohr Institute, where Associate Professor Amin Doostmohammadi, who heads a research group that simulates biologically active materials, contributed with the modelling of filopodia behaviour.

"It is very interesting that Amin Doostmohammadi could simulate the mechanical movements we witnessed through the microscope, completely independent of chemical and biological details," explains Poul Martin Bendix.

The main reason that the team succeeded in being the first to describe the mechanical behaviour of filopodia is that NBI has unique equipment for this type of experiment, as well as skilled researchers with tremendous experience working with optical tweezers. When an object is extraordinarily small, holding onto it mechanically becomes impossible. However, it can be held and moved using a laser beam with a wavelength carefully calibrated to the object being studied. This is called an optical tweezers.

"At NBI, we have some of the world's best optical tweezers for biomechanical studies. The experiments require the use of several optical tweezers and the simultaneous deployment of ultra-fine microscopy," explains Poul Martin Bendix.

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Chaos theory provides hints for controlling the weather

Under a project led by the RIKEN Center for Computational Science, researchers have used computer simulations to show that weather phenomena such as sudden downpours could potentially be modified by making small adjustments to certain variables in the weather system. They did this by taking advantage of a system known as a "butterfly attractor" in chaos theory, where a system can have one of two states -- like the wings of a butterfly -- and that it switches back and forth between the two states depending on small changes in certain conditions.

While weather predictions have reached levels of high accuracy thanks to methods such as supercomputer-based simulations and data assimilation, where observational data is incorporated into simulations, scientists have long hoped to be able to control the weather. Research in this area has intensified due to climate change, which has led to more extreme weather events such as torrential rain and storms.

There are methods at present for weather modification, but they have had limited success. Seeding the atmosphere to induce rain has been demonstrated, but it is only possible when the atmosphere is already in a state where it might rain. Geoengineering projects have been envisioned, but have not been carried out due to concerns about what unpredicted long-term effects they might have.

As a promising approach, researchers from the RIKEN team have looked to chaos theory to create realistic possibilities for mitigating weather events such as torrential rain. Specifically, they have focused on a phenomenon known as a butterfly attractor, proposed by mathematician and meteorologist Edward Lorentz, one of the founders of modern chaos theory. Essentially, this refers to a system that can adopt one of two orbits that look like the wings of a butterfly, but can change the orbits randomly based on small fluctuations in the system.

To perform the work, the RIKEN team ran one weather simulation, to serve as the control of "nature" itself, and then ran other simulations, using small variations in a number of variables describing the convection -- how heat moves through the system -- and discovered that small changes in several of the variables together could lead to the system being in a certain state once a certain amount of time elapsed.

According to Takemasa Miyoshi of the RIKEN Center for Computational Science, who led the team, "This opens the path to research into the controllability of weather and could lead to weather control technology. If realized, this research could help us prevent and mitigate extreme windstorms, such as torrential rains and typhoons, whose risks are increasing with climate change."

"We have built a new theory and methodology for studying the controllability of weather," he continues. "Based on the observing system simulation experiments used in previous predictability studies, we were able to design an experiment to investigate predictability based on the assumption that the true values (nature) cannot be changed, but rather that we can change the idea of what can be changed (the object to be controlled)."

Looking to the future, he says, "In this case we used an ideal low-dimensional model to develop a new theory, and in the future we plan to use actual weather models to study the possible controllability of weather."

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Scientists discover body's natural alarm to battle blood loss

University of Virginia School of Medicine scientists have discovered a cluster of cells in the brainstem that controls the body's response to severe blood loss, a finding which could benefit efforts to develop new treatments for traumatic injuries.

The discovery pinpoints a collection of neurons that drives a response that maintains blood pressure during blood loss. However, severe blood loss eventually causes cardiovascular collapse -- a condition termed "decompensated hemorrhage" marked by an abrupt and dangerous loss of blood pressure -- and the new results shed light on why that happens.

"During blood loss, the brain coordinates a cardiovascular response that supports blood flow to critical organs, like the heart and brain,"said researcher George Souza, PhD, of UVA's Department of Pharmacology. "Our study shows that the cardiovascular response to blood loss depends on changes in the activity of a few hundred neurons in the brainstem."

Under Pressure

The new results, from UVA's Stephen Abbott, PhD, and collaborators, shed light on an important process the body uses to maintain its blood pressure. The neurons Abbott and his team describe -- properly known as "adrenergic C1 neurons" -- monitor blood pressure and swing into action during blood loss. When the neurons detect blood loss, they increase nerve activity that constricts blood vessels and maintains proper blood pressure.

The scientists were able to determine this using advanced imaging and a technique called optogenetics that allows for the remote control of neurons using light. Their research revealed that the C1 neurons are hyperactive during blood loss, and this maintains blood pressure. But these neurons become inactive with severe blood loss, resulting in cardiovascular collapse.

Decompensated hemorrhage is the prelude to hemorrhagic shock, in which the body begins to shut down. But the scientists found that re-activating the C1 neurons in lab rats restored both blood pressure and heart rate.

"Our study indicates that reactivating the brain pathways controlling blood pressure during decompensated hemorrhage effectively reverses cardiovascular collapse. We think this indicates that neuromodulation of the pathways described by our study could be a beneficial adjunct therapy for low blood pressure following blood loss," said Abbott, of UVA's Department of Pharmacology.

The scientists note that there may be several factors that contribute to the decline in the activity of the C1 neurons during the onset of decompensated hemorrhage. More research on that front is needed. But the team's findings identify important new directions for that future research.

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Nearby star could help explain why our Sun didn’t have sunspots for 70 years

The number of sunspots on our Sun typically ebbs and flows in a predictable 11-year cycle, but one unusual 70-year period when sunspots were incredibly rare has mystified scientists for three hundred years. Now a nearby Sun-like star seems to have paused its own cycles and entered a similar period of rare starspots, according to a team of researchers at Penn State. Continuing to observe this star could help explain what happened to our own Sun during this "Maunder Minimum" as well as lend insight into the Sun's stellar magnetic activity, which can interfere with satellites and global communications and possibly even affect climate on Earth.

The star -- and a catalog of 5 decades of starspot activity of 58 other Sun-like stars -- is described in a new paper that appears online in the Astronomical Journal.

Starspots appear as a dark spot on a star's surface due to temporary lower temperatures in the area resulting from the star's dynamo -- the process that creates its magnetic field. Astronomers have been documenting changes in starspot frequency on our Sun since they were first observed by Galileo and other astronomers in the 1600s, so there is a good record of its 11-year cycle. The exception is the Maunder Minimum, which lasted from the mid 1600s to early 1700s and has perplexed astronomers ever since.

"We don't really know what caused the Maunder Minimum, and we have been looking to other Sun-like stars to see if they can offer some insight," said Anna Baum, an undergraduate at Penn State at the time of the research and first author of the paper. "We have identified a star that we believe has entered a state similar to the Maunder Minimum. It will be really exciting to continue to observe this star during, and hopefully as it comes out of, this minimum, which could be extremely informative about the Sun's activity three hundred years ago."

The research team pulled data from multiple sources to stitch together 50 to 60 years of starspot data for 59 stars. This included data from the Mount Wilson Observatory HK Project -- which was designed to study stellar surface activity and ran from 1966 to 1996 -- and from planet searches at Keck Observatory which include this kind of data as part of their ongoing search for exoplanets from 1996 to 2020. The researchers compiled a database of stars that appeared in both sources and that had other readily available information that might help explain starspot activity. The team also made considerable efforts to standardize measurements from the different telescopes to be able to compare them directly and otherwise clean up the data.

The team identified or confirmed that 29 of these stars have starspot cycles by observing at least two full periods of cycles, which often last more than a decade. Some stars did not appear to have cycles at all, which could be because they are rotating too slowly to have a dynamo and are magnetically 'dead' or because they are near the end of their lives. Several of the stars require further study to confirm whether they have a cycle.

"This continuous, more than 50-year time series allows us to see things that we never would have noticed from the 10-year snapshots that we were doing before," said Jason Wright, professor of astronomy and astrophysics at Penn State and an author of the paper. "Excitingly, Anna has found a promising star that was cycling for decades but appears to have stopped."

According to the researchers, the star -- called HD 166620 -- was estimated to have a cycle of about 17 years but has now entered a period of low activity and has shown no signs of starspots since 2003.

"When we first saw this data, we thought it must have been a mistake, that we pulled together data from two different stars or there was a typo in the catalog or the star was misidentified," said Jacob Luhn, a graduate student at Penn State when the project began who is now at the University of California, Irvine. "But we double and triple checked everything. The times of observation were consistent with the coordinates we expected the star to have. And there aren't that many bright stars in the sky that Mount Wilson observed. No matter how many times we checked, we always come to the conclusion that this star has simply stopped cycling."

The researchers hope to continue studying this star throughout its minimum period and potentially as it comes out of its minimum and begins to cycle once again. This continued observation could provide important information about how the Sun and stars like it generate their magnetic dynamos.

"There's a big debate about what the Maunder Minimum was," said Baum, who is now a doctoral student at Lehigh University studying stellar astronomy and asteroseismology . "Did the Sun's magnetic field basically turn off? Did it lose its dynamo? Or was it still cycling but at a very low level that didn't produce many sunspots? We can't go back in time to take measurements of what it was like, but if we can characterize the magnetic structure and magnetic field strength of this star, we might start to get some answers."

A better understanding of the surface activity and magnetic field of the Sun could have several important implications. For example, strong stellar activity can disable satellites and global communications, and one particularly strong solar storm disabled a power grid in Quebec in 1989. It has also been suggested that sunspot cycles may have a connection to climate on Earth. Additionally, the researchers said that information from this star could impact our search for planets beyond our solar system.

"Starspots and other forms of surface magnetic activity of stars interfere with our ability to detect the planets around them," said Howard Isaacson, a research scientist at the University of California, Berkeley, and an author of the paper. "Improving our understanding of a star's magnetic activity might help us improve our detection efforts."

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Large study challenges the theory that light alcohol consumption benefits heart health

Observational research has suggested that light alcohol consumption may provide heart-related health benefits, but in a large study published in JAMA Network Open, alcohol intake at all levels was linked with higher risks of cardiovascular disease. The findings, which are published by a team led by researchers at Massachusetts General Hospital (MGH) and the Broad Institute of MIT and Harvard, suggest that the supposed benefits of alcohol consumption may actually be attributed to other lifestyle factors that are common among light to moderate drinkers.

The study included 371,463 adults -- with an average age of 57 years and an average alcohol consumption of 9.2 drinks per week -- who were participants in the UK Biobank, a large-scale biomedical database and research resource containing in-depth genetic and health information. Consistent with earlier studies, investigators found that light to moderate drinkers had the lowest heart disease risk, followed by people who abstained from drinking. People who drank heavily had the highest risk. However, the team also found that light to moderate drinkers tended to have healthier lifestyles than abstainers -- such as more physical activity and vegetable intake, and less smoking. Taking just a few lifestyle factors into account significantly lowered any benefit associated with alcohol consumption.

The study also applied the latest techniques in a method called Mendelian randomization, which uses genetic variants to determine whether an observed link between an exposure and an outcome is consistent with a causal effect -- in this case, whether light alcohol consumption causes a person to be protected against cardiovascular disease. "Newer and more advanced techniques in 'non-linear Mendelian randomization' now permit the use of human genetic data to evaluate the direction and magnitude of disease risk associated with different levels of an exposure," says senior author Krishna G. Aragam, MD, MS, a cardiologist at MGH and an associate scientist at the Broad Institute. "We therefore leveraged these new techniques and expansive genetic and phenotypic data from biobank populations to better understand the association between habitual alcohol intake and cardiovascular disease."

When the scientists conducted such genetic analyses of samples taken from participants, they found that individuals with genetic variants that predicted higher alcohol consumption were indeed more likely to consume greater amounts of alcohol, and more likely to have hypertension and coronary artery disease. The analyses also revealed substantial differences in cardiovascular risk across the spectrum of alcohol consumption among both men and women, with minimal increases in risk when going from zero to seven drinks per week, much higher risk increases when progressing from seven to 14 drinks per week, and especially high risk when consuming 21 or more drinks per week. Notably, the findings suggest a rise in cardiovascular risk even at levels deemed "low risk" by national guidelines from the U.S. Department of Agriculture (i.e. below two drinks per day for men and one drink per day for women).

The discovery that the relationship between alcohol intake and cardiovascular risk is not a linear one but rather an exponential one was supported by an additional analysis of data on 30,716 participants in the Mass General Brigham Biobank. Therefore, while cutting back on consumption can benefit even people who drink one alcoholic beverage per day, the health gains of cutting back may be more substantial -- and, perhaps, more clinically meaningful -- in those who consume more.

"The findings affirm that alcohol intake should not be recommended to improve cardiovascular health; rather, that reducing alcohol intake will likely reduce cardiovascular risk in all individuals, albeit to different extents based on one's current level of consumption," says Aragam.

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