Cold planets exist throughout our Galaxy, even in the galactic bulge

Although thousands of planets have been discovered in the Milky Way, most reside less than a few thousand light years from Earth. Yet our Galaxy is more than 100,000 light years across, making it difficult to investigate the Galactic distribution of planets. But now, a research team has found a way to overcome this hurdle.

In a study published in The Astrophysical Journal Letters, researchers led by Osaka University and NASA have used a combination of observations and modeling to determine how the planet-hosting probability varies with the distance from the Galactic center.

The observations were based on a phenomenon called gravitational microlensing, whereby objects such as planets act as lenses, bending and magnifying the light from distant stars. This effect can be used to detect cold planets similar to Jupiter and Neptune throughout the Milky Way, from the Galactic disk to the Galactic bulge -- the central region of our Galaxy.

"Gravitational microlensing currently provides the only way to investigate the distribution of planets in the Milky Way," says Daisuke Suzuki, co-author of the study. "But until now, little is known mainly because of the difficulty in measuring the distance to planets that are more than 10,000 light years from the Sun."

To solve this problem, the researchers instead considered the distribution of a quantity that describes the relative motion of the lens and distant light source in planetary microlensing. By comparing the distribution observed in microlensing events with that predicted by a Galactic model, the research team could infer the Galactic distribution of planets.

The results show that the planetary distribution is not strongly dependent on the distance from the Galactic center. Instead, cold planets orbiting far from their stars seem to exist universally in the Milky Way. This includes the Galactic bulge, which has a very different environment to the solar neighborhood, and where the presence of planets has long been uncertain.

"Stars in the bulge region are older and are located much closer to each other than stars in the solar neighborhood," explains lead author of the study Naoki Koshimoto. "Our finding that planets reside in both these stellar environments could lead to an improved understanding of how planets form and the history of planet formation in the Milky Way."

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Secret garden: Drug-resistant pathogen strains meet and evolve on plant bulbs

Just when we thought it was safe to go to the local garden center, researchers from Japan have discovered that fungicide-resistant strains of a nasty pathogen have been getting up to no good among the tulip bulbs.

In a study published in August in Environmental Microbiology researchers from the University of Tsukuba and Chiba University have revealed that plant bulbs harboring a potentially lethal pathogen also make the perfect lab for evolving fungicide-resistant strains.

The risk associated with fungal infections is increasing, with occurrences of pulmonary aspergillosis (PA), a deadly fungal infection caused by the human pathogen Aspergillus fumigatus, rising globally. Of particular concern are influenza-related PA and COVID-19-related PA, the case numbers of which are growing quickly. Azoles -- a class of antifungal compounds often used as antifungal drugs to treat aspergillosis -- are also widely used as agricultural fungicides. Azole-resistant strains of A. fumigatus are spreading in the environment, potentially promoted by agricultural azole use. Azole resistance is a factor known to affect the treatment of PA, and there is concern that this problem is only worsening.

"Understanding how the genetic variation linked with azole resistance in A. fumigatus strains is distributed and enriched in the environment is necessary for suppressing resistant strains," says senior author of the study Daisuke Hagiwara. "In this study, we set out to do this by investigating the genetics of those strains."

Previously, the research team found several azole-resistant A. fumigatus strains attached to imported plant bulbs for sale in Japanese gardening shops. In this study, they investigated eight strains of azole-resistant A. fumigatus isolated from a single tulip bulb bought in Japan. The researchers used genome sequencing and comparative analysis, and compared the strains for sensitivity to agricultural and medical azoles, in addition to other classes of fungicides. The results indicated that there had previously been genetic recombination between the strains, and that some of them exhibited tolerance to other fungicide classes.

"Our results show that plant bulbs provide not just a vehicle for this pathogen, but also an ideal niche for its strains to encounter each other, and to evolve their resistance to drugs," says Hagiwara.

This study fills gaps in the knowledge of azole-resistant A. fumigatus, providing important information on the genetics behind an urgent global One Health challenge. The research team's findings will inform a deeper understanding of drug-resistant fungi and help with the development of future solutions to this problem.

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Stellar collision triggers supernova explosion

Astronomers have found dramatic evidence that a black hole or neutron star spiraled its way into the core of a companion star and caused that companion to explode as a supernova. The astronomers were tipped off by data from the Very Large Array Sky Survey (VLASS), a multi-year project using the National Science Foundation's Karl G. Jansky Very Large Array (VLA).

"Theorists had predicted that this could happen, but this is the first time we've actually seen such an event," said Dillon Dong, a graduate student at Caltech and lead author on a paper reporting the discovery in the journal Science.

The first clue came when the scientists examined images from VLASS, which began observations in 2017, and found an object brightly emitting radio waves but which had not appeared in an earlier VLA sky survey, called Faint Images of the Radio Sky at Twenty centimeters (FIRST). They made subsequent observations of the object, designated VT 1210+4956, using the VLA and the Keck telescope in Hawaii. They determined that the bright radio emission was coming from the outskirts of a dwarf, star-forming galaxy some 480 million light-years from Earth. They later found that an instrument aboard the International Space Station had detected a burst of X-rays coming from the object in 2014.

The data from all these observations allowed the astronomers to piece together the fascinating history of a centuries-long death dance between two massive stars. Like most stars that are much more massive than our Sun, these two were born as a binary pair, closely orbiting each other. One of them was more massive than the other and evolved through its normal, nuclear fusion-powered lifetime more quickly and exploded as a supernova, leaving behind either a black hole or a superdense neutron star.

The black hole or neutron star's orbit grew steadily closer to its companion, and about 300 years ago it entered the companion's atmosphere, starting the death dance. At this point, the interaction began spraying gas away from the companion into space. The ejected gas, spiraling outward, formed an expanding, donut-shaped ring, called a torus, around the pair.

Eventually, the black hole or neutron star made its way inward to the companion star's core, disrupting the nuclear fusion producing the energy that kept the core from collapsing of its own gravity. As the core collapsed, it briefly formed a disk of material closely orbiting the intruder and propelled a jet of material outward from the disk at speeds approaching that of light, drilling its way through the star.

"That jet is what produced the X-rays seen by the MAXI instrument aboard the International Space Station, and this confirms the date of this event in 2014," Dong said.

The collapse of the star's core caused it to explode as a supernova, following its sibling's earlier explosion.

"The companion star was going to explode eventually, but this merger accelerated the process," Dong said.

The material ejected by the 2014 supernova explosion moved much faster than the material thrown off earlier from the companion star, and by the time VLASS observed the object, the supernova blast was colliding with that material, causing powerful shocks that produced the bright radio emission seen by the VLA.

"All the pieces of this puzzle fit together to tell this amazing story," said Gregg Hallinan of Caltech. "The remnant of a star that exploded a long time ago plunged into its companion, causing it, too, to explode," he added.

The key to the discovery, Hallinan said, was VLASS, which is imaging the entire sky visible at the VLA's latitude -- about 80 percent of the sky -- three times over seven years. One of the objectives of doing VLASS that way is to discover transient objects, such as supernova explosions, that emit brightly at radio wavelengths. This supernova, caused by a stellar merger, however, was a surprise.

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New evidence supports idea that America’s first civilization was made up of ‘sophisticated’ engineers

The Native Americans who occupied the area known as Poverty Point in northern Louisiana more than 3,000 years ago long have been believed to be simple hunters and gatherers. But new Washington University in St. Louis archaeological findings paint a drastically different picture of America's first civilization.

Far from the simplicity of life sometimes portrayed in anthropology books, these early Indigenous people were highly skilled engineers capable of building massive earthen structures in a matter of months -- possibly even weeks -- that withstood the test of times, the findings show.

"We as a research community -- and population as a whole -- have undervalued native people and their ability to do this work and to do it quickly in the ways they did," said Tristram R. "T.R." Kidder, lead author and the Edward S. and Tedi Macias Professor of Anthropology in Arts & Sciences.

"One of the most remarkable things is that these earthworks have held together for more than 3,000 years with no failure or major erosion. By comparison, modern bridges, highways and dams fail with amazing regularity because building things out of dirt is more complicated than you would think. They really were incredible engineers with very sophisticated technical knowledge."

The findings were published in Southeastern Archaeology on September, 1, 2021. Washington University's Kai Su, Seth B. Grooms, along with graduates Edward R. Henry (Colorado State) and Kelly Ervin (USDA Natural Resources Conservation Service) also contributed to the paper.

The Poverty Point World Heritage site consists of a massive 72-foot-tall earthen mound and concentric half circle ridges. The structures were constructed by hunter-gatherers approximately 3,400 years ago from nearly 2 million cubic yards of soil. Amazingly, this was done without the luxury of modern tools, domesticated animals or even wheeled carts.

According to Kidder, the site was likely an important religious site where Native Americans came in pilgrimage, similar to Mecca. It was abandoned abruptly between 3,000-3,200 years ago -- most likely due to documented flooding in the Mississippi Valley and climate change.

The ridges at Poverty Point contain vast amounts of artifacts around the edges and within, suggesting that people lived there. Kidder and team re-excavated and re-evaluated a site on Ridge West 3 at the Poverty Point Site that was originally excavated by renowned archaeologist Jon Gibson in 1991.

Using modern research methods including radiocarbon dating, microscopic analysis of soils and magnetic measurements of soils, the research provides conclusive evidence that the earthworks were built rapidly. Essentially, there is no evidence of boundaries or signs of weathering between the various levels, which would have occurred if there was even a brief pause in construction. Kidder believes the construction was completed in lifts, or layers of sediment deposited to increase the ridge height and linear dimensions before another layer was placed to expand the footprint vertically and horizontally.

Why does that matter? According to Kidder, the findings challenge previous beliefs about how pre-modern hunters and gatherers behaved. Building the enormous mounds and ridges at Poverty Point would have required a large labor pool that was well organized and would have required leadership to execute. Hunters and gathers were believed to shun politics.

"Between the speed of the excavation and construction, and the quantity of earth being moved, these data show us native people coming to the site and working in concert. This in and of itself is remarkable because hunter-gatherers aren't supposed to be able to do these activities," Kidder said.

What's even more impressive than how quickly the people built the earthen structures is the fact that they're still intact. Due to its proximity to the Gulf of Mexico, this area receives immense amounts of rain that makes earthworks especially prone to erosion. Microscopic analysis of soils shows that the Native Americans mixed different types of soil -- clays, silts and sand -- in a calculated recipe to make the structures stronger.

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Gut and heart signals affect how we see ourselves

New research has discovered that the strength of the connection between our brain and internal organs is linked to how we feel about our appearance.

Published in the journal Cortex, the study is the first to investigate, and first to identify, the association between body image and the brain's processing of internal signals that occur unconsciously.

Carried out by a team of psychologists and neuroscientists at Anglia Ruskin University (ARU), the study found that adults whose brains are less efficient at detecting these internal messages are more likely to experience body shame and weight preoccupation.

This research could have therapeutic implications for people suffering with conditions in which body image plays a significant role. For example, the unconscious signals could be made conscious. Further research could even be applied to the clinic as it may be the case that brain responses to gut signals could indicate a predisposition to eating disorders.

The study participants -- a group of healthy UK adults -- first took part in four body image assessments to measure their feelings of body appreciation, body functionality appreciation, body shame, and weight preoccupation.

The researchers then carried out measurements of the participants' internal signals. Some of the messages from the heart and gut are processed at an unconscious level and the nervous system interprets these signals to provide the brain with continuously updated information about the body's internal state.

The strength of the connection between the gut and the brain was measured by recording the electrical activity of both regions at the same time. The researchers also measured brain responses to heartbeats.

They found that weaker brain responses to the gut and heart were both significantly associated with greater levels of body shame and weight preoccupation amongst the participants.

Senior author Dr Jane Aspell, Associate Professor of Cognitive Neuroscience at Anglia Ruskin University (ARU), said: "We experience our body both from the inside and out: we can be aware of how our skin and limbs look, but also of how hungry we feel or how strongly our heart is beating during exercise. The brain also continuously processes internal signals that we are not conscious of.

"We found that when the brain is less responsive to these implicit signals from inside the body, individuals are more likely to hold negative views about their external bodily appearance. It may be that when the brain has a weaker connection to the internal body, the brain puts more emphasis on the external body and so appearance becomes much more important for self-evaluation."

Lead author Dr Jennifer Todd, a Postdoctoral Research Fellow at Anglia Ruskin University (ARU), said: "Our research could have implications for those experiencing negative body image, which can have a serious impact on people's lives.

"The gut and heart signal measurements used in our study could potentially act as a biomarker to help identify, or even predict, negative body image and associated conditions, such as eating disorders. Additionally, by training people to become more aware of internal sensations, it might be possible to amplify these unconscious signals.

"We need to understand why some brains are better at detecting these internal signals than others. We expect it is partly due to differences in neuro-anatomical connections between the brain and internal organs, and this will be the subject of future research."

Meanwhile, Dr Jane Aspell will be speaking about her research on the body and sense of self in a talk at the British Science Festival 2021, 7-11 September hosted by the British Science Association at Anglia Ruskin University. The talk will explore research on out of body experiences (OBEs), and she will share case studies from neurological patients.

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Many with food allergies don’t know about oral immunotherapy treatment option

A study of a geographically, clinically, and socioeconomically diverse, nationally-representative sample of US households -- including both adult patients and caregivers of children with food allergy -- found that 72 percent did not know what oral immunotherapy (OIT) was prior to the survey. Researchers also discovered that current OIT awareness is disproportionately elevated among wealthier, more highly educated respondents, which underscores the need for more equitable outreach efforts and greater access to these therapies for all patients with food allergies. Findings were published in the Journal of Allergy and Clinical Immunology: In Practice.

Food allergy is a significant health concern affecting approximately 8 percent of children and 10 percent of adults in the U.S. Currently, recommended food allergy management involves strict avoidance of the offending food and ensuring ready access to epinephrine. This poses a great challenge for patients and families as it can impair quality of life, impose financial burdens, and potentially result in life threatening anaphylaxis following accidental ingestion. In 2020, the FDA approved Palforzia®, a drug product from peanut flour, for use in OIT, making it the first approved treatment for patients with peanut allergy, ages 4-17 years.

"With the ongoing expansion of oral immunotherapy offerings and additional therapies on the horizon, it is important to ensure equitable access to all treatments for food allergy," said senior author Ruchi Gupta, MD, MPH, a pediatrician and food allergy researcher at Ann & Robert H. Lurie Children's Hospital of Chicago and Professor of Pediatrics at Northwestern University Feinberg School of Medicine. "The latest epidemiological data indicates that approximately half of US food-allergic children are either Black, Hispanic/Latinx, or multi-racial, populations which have historically encountered greater barriers to specialty care owing to lower socioeconomic status. It is critical that we reach these children and create greater awareness of oral immunotherapy, so that they too can benefit from recent advances in food allergy treatments."

Surveys were completed by 781 respondents from all 50 states. Respondents were required to report a physician-diagnosed food allergy to be eligible for the study.

"Our Community Access Initiative strives to understand barriers like the one found in this study and develop the programs and resources to address the need," said Anita Roach, MS, FARE, VP of Community Programs & Education. "Income and level of education should not be a factor in access to food allergy care or support."

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Geologists propose theory about a famous asteroid

The asteroid Vesta is the second largest asteroid in our solar system. With a diameter of about 330 miles, it orbits the sun between the planets Mars and Jupiter.

Asteroids have long played a part in building popular fascination with space. "Marooned off Vesta" was the first story published by American writer Isaac Asimov, the third story he wrote, appearing in the March 1939 issue of the science fiction magazine Amazing Stories.

"When we think of asteroid belts, we probably picture Han Solo maneuvering the millennium falcon through a dense set of irregularly shaped gray rocks in space," Christian Klimczak, associate professor in the Franklin College of Arts and Sciences department of geology. "While most rocks are indeed irregularly shaped and gray, they are far apart and NASA's Dawnspacecraft did not have to maneuver around any other asteroids to reach and explore Vesta."

Dawnwas the space probe launched by NASA in September 2007 with the mission of studying two of the three known protoplanets of the asteroid belt, Vesta and Ceres.

Vesta, like Earth, is composed of rock in its crust and mantle, and it has an iron core. Because of its large size (for an asteroid) and because Vesta has a crust, mantle and core, it is considered a planetesimal. Planetesimals are building blocks out of which planets form. Earth formed by accretion of several such planetesimals. "Vesta was on the way to becoming an Earth-like planet, too, but planet formation stopped along the way there early in the history of our solar system," Klimczak said. "Therefore, studying Vesta helps us understand the very early days of our planetary neighborhood and how our own planet formed."

Klimczak is co-author on a new study that examines the large-scale troughs and impact basins on Vesta.

What created those giant troughs on Vesta?

Vesta was hit by two other large asteroids which left large impact craters so big they cover most of the southern hemisphere of Vesta. These impacts are thought to have ejected rocky material into space. Some of these rocks reached Earth as meteorites so scientists now have actual rock samples from Vesta to study its geochemistry.

"Rock properties are influenced by environmental conditions like surrounding stresses and the presence of water," said Jupiter Cheng, doctoral candidate in the department of geography and co-author on the study. "Since Vesta is much smaller than Earth, or even the moon, it has a weaker gravity, and rock would deform differently near the surface than what we see on Earth."

According to Cheng, one big question is what triggered the formation of these large troughs. The two troughs are concentric around the two massive impact basins, Rheasilvia and Veneneia, respectively, and widely considered to be simultaneously formed by the impact events, though this assumed age relationship has never been tested before.

"Our work used crater counting methods to explore the relative age of the basins and troughs," Cheng said. Crater counting is a common method for estimating the age of a planet's surface, a method based upon the assumptions that when a piece of planetary surface is new, then it has no impact craters; impact craters accumulate after that at a rate that is assumed known.

"Consequently, counting the number of craters of various sizes in a given area allows us to determine how long they have accumulated and, consequently, how long ago the surface formed," she said. "Our result shows that the troughs and basins have a similar number of the crater of various sizes, indicating they share a similar age. However, the uncertainties associated with the crater counts allow for the troughs to have formed well after the impacts.

The origin of the troughs has long been a point of conjecture within the scientific community. Klimczak hopes their new geologic evidence can promote a more-durable theory about the troughs on Vesta.

The study is published in the September issue of the journal Icarus.

A new theory is proposed in an upcoming paper

"The leading hypothesis suggests that these troughs are fault-bounded valleys with a distinct scarp on each side that together mark the down-drop (sliding) of a block of rock. However, rock can also crack apart and form such troughs, an origin that has not been considered before," said Cheng, who is investigating the origin of the troughs as part of her dissertation at UGA.

"Our calculations also show that Vesta's gravity is not enough to induce surrounding stresses favorable for sliding to occur at shallow depths, instead, the physics shows that rocks there are favored to crack apart," she said. "Therefore, the formation of these troughs must involve the opening of cracks, which is inconsistent with the leading hypothesis in the scientific community. Taken all together, the overall project provides alternatives to the previously proposed trough origin and geological history of Vesta, results that are also important for understanding similar landforms on other small planetary bodies elsewhere in the solar system."

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Decades after toxic exposure, 9/11 first responders may still lower their risk of lung injury

Losing weight and treating excess levels of fat in the blood may help prevent lung disease in firefighters exposed to dangerous levels of fine particles from fire, smoke, and toxic chemicals on Sept. 11, 2001, a new study shows. Experts have long feared that this exposure would later lead to lung disease in first responders. High body mass index (BMI), an indicator of obesity, and exposure to the highest levels of toxins from the attack on the World Trade Center were the two greatest risk factors for lowered lung function, according to the study authors.

After two decades of research analyzing thousands of first responders, a new investigation led by researchers at NYU Grossman School of Medicine identified a cluster of five factors that predicted lung disease in these patients. Along with excess body fat, the combination of insulin resistance, high blood pressure, and increased levels of sugar and cholesterol in the blood are components of so-called metabolic syndrome, a group of medical issues known to raise the risk of heart disease, stroke, and diabetes.

Adjusting at least one of these factors, the study investigators found, can greatly lower the risk of firefighters' developing lung disease within five years, even 20 years after toxic exposures at Ground Zero. For example, for a male firefighter of average height, a 7-pound weight loss could decrease his risk for lung injury by 20 percent.

"Our findings should reassure World Trade Center first responders that there are steps they can take to protect their lungs even decades after exposure," says study co-lead author Sophia Kwon, DO, MPH. Kwon is a fellow in the Division of Pulmonary, Critical Care, and Sleep at NYU Langone Health.

In work presented earlier this year on 100 overweight 9/11 firefighters, the team found that placing patients on a calorie-restricted Mediterranean diet featuring unrefined grains, olive oil, fruits, and fish reduced their risk of lung disease. Those following the regimen for six months lost nearly 2 BMI points (from an average BMI of about 33 to an average of 31) and had fewer signs of lung disease than they had reported before the study period.

"These results offer firefighters a concrete way to lose weight and achieve the lung-health benefits predicted by our risk model," says study co-lead author George Crowley, BA, a predoctoral fellow at NYU Langone.

Experts had previously understood that first responders who developed metabolic syndrome shortly after 9/11 were more likely to have higher rates of asthma. However, lung injury risks for a firefighter whose metabolic syndrome instead appeared later in life remained unclear until now.

The new study, publishing Sept. 2 in the American Journal of Respiratory and Critical Care Medicine, is part of what is likely the longest-running and most thorough exploration of the impact of metabolic syndrome on lung injury in 9/11 firefighters, according to the study authors. In addition, the investigation is the first to date to quantify how adjusting one or more of these risk factors changes lung disease risk.

For the investigation, the research team analyzed 20 years of data from more than 5,700 firefighters active on 9/11, of whom 1,475 later developed lung disease. Along with BMI, the data collected included smoking history, and whether they had served at the World Trade Center in early morning when pollutant exposure was at its peak.

"The lessons from our investigation can be applied not only to firefighters but to the millions of city dwellers exposed to air pollution on a daily basis," says study senior author and pulmonologist Anna Nolan, MD. "They should be aware that while their environment poses real health risks, they may still minimize their risk of lung disease even if they cannot change their exposure."

Nolan, a professor in the Departments of Medicine and Environmental Health at NYU Langone, cautions that while promising, the Mediterranean diet investigation only examined a small, specific group.

As a result, the research team next plans to expand the study to determine whether the diet could benefit a more diverse population who have been similarly exposed to urban pollutants. They also plan to explore how metabolic syndrome may affect other measures of lung function like asthma, says Nolan.

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With time and without masks, COVID-19 vaccines wane in protection, study finds

In a letter to The New England Journal of Medicine, publishing online September 1, 2021, an interdisciplinary team of physicians and public health experts at University of California San Diego measured the effectiveness of COVID-19 mRNA vaccines among health workers at UC San Diego Health, most notably during the emergence of the highly transmissible delta virus variant and coincident with the end of the state's mask mandate, allowing fully vaccinated persons to forgo face coverings in most places.

The letter's authors report that the effectiveness of both the Pfizer and Moderna mRNA COVID-19 vaccines significantly waned over time. Both vaccines were granted emergency use authorization by the Food and Drug Administration in December 2020, with vaccinations of the UC San Diego Health work force beginning the same month for health care workers with direct, patient-facing duties.

In the letter, the authors note that from March through June 2021 vaccine effectiveness against symptomatic infection was estimated to exceed 90 percent; by July, however, it had fallen to approximately 65 percent.

"The decline in effectiveness is not entirely surprising," said co-senior author Francesca Torriani, MD, professor of clinical medicine in the Division of Infectious Diseases and Global Public Health in the UC San Diego School of Medicine and program director of Infection Prevention and Clinical Epidemiology at UC San Diego Health.

"Clinical trial data suggested decreased effectiveness would occur several months after full vaccination, but our findings indicate that confronted by the delta variant, vaccine effectiveness for mildly symptomatic disease was considerably lower and waned six to eight months after completing vaccination."

UC San Diego Health, with a work force of approximately 19,000, operates a robust SARS-CoV-2 testing program. If an employee reports even one mild symptom of COVID-19 during daily screening or an identified exposure, a test is triggered.

Then and now, UC San Diego Health has maintained rigorous, mandatory masking and transmission mitigation measures throughout its hospitals and clinical facilities. Diagnosed positive cases among health workers have universally been identified as community acquired.

In December 2020, workers at UC San Diego Health, like the population overall, began experiencing a surge of SARS-CoV-2 infections, the virus that causes COVID-19.

The situation improved significantly after UC San Diego Health began to inoculate employees using the Pfizer and Moderna vaccines. By March 2021, 76 percent of workers were fully vaccinated, rising to 83 percent by July 2021.

Concomitant with increased vaccination coverage was a decline between March and June in the number of workers reporting at least one symptom of COVID-19 and a positive PCR test. That number declined to fewer than 30 employees per month.

In July 2021, however, cases among this highly vaccinated population began to rise again, coincident with the emerging dominance of the delta variant in San Diego and the ending of California's masking mandate on June 15. By July, 125 workers had been diagnosed with SARS-CoV-2 and unlike in previous months when approximately 20 percent of these cases involved vaccinated workers, the percentage had risen to 75 percent.

Notably, the vaccines still provide significant protection from severe infection outcomes, such as hospitalization and death. Among the UC San Diego Health employee cases documented, no hospitalizations were reported in vaccinated individuals and only one among unvaccinated persons.

"Unlike what was experienced with other variants, with the delta variant parents are frequently getting infected by their young children, ages 5 to 11," said co-first author Lucy Horton, MD, MPH, an assistant professor of medicine in the Division of Infectious Diseases and director of the UC San Diego Health COVID-19 case investigation and contact tracing team. "Unvaccinated people are seven times more likely to test positive for COVID-19 than those who are fully vaccinated. More importantly, while children rarely need medical attention, unvaccinated adults are 32 times more likely to require hospitalization compared to those who are fully vaccinated."

Vaccine effectiveness was linked to the passage of time. For workers diagnosed in July, those who became fully vaccinated in January and February had higher infection rates than those vaccinated later in March through May. The infection rate among unvaccinated persons has remained consistently higher than for any vaccinated group, although the difference in rates between the two groups has decreased over time.

"The dramatic change in vaccine effectiveness from June to July is likely due to a combination of factors," said co-author Nancy Binkin, MD, MPH, professor of epidemiology in the UC San Diego School of Medicine and Herbert Wertheim School of Public Health and Human Longevity Science. "It's the emergence of the delta variant and waning immunity over time, compounded by the end of broad masking requirements and the resulting greater exposure risk throughout the community."

Co-senior author Shira Abeles, MD, an assistant professor of medicine in the Division of Infectious Diseases who has led the COVID-19 vaccination effort at UC San Diego Health, said the findings underscore the importance of rapidly reinstating key interventions, such as indoor masking and intensive testing strategies, plus continuing efforts to boost vaccination rates.

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The physics behind a tardigrade's lumbering gait

Plump and ponderous, tardigrades earned the nickname "water bears" when scientists first observed the 0.02-inch-long animals' distinctive lumbering gaits in the 18th century. Their dumpy plod, however, raises the question of why tardigrades evolved to walk at all.

Animals as small and soft as tardigrades seldom have legs and almost never bother walking. For example, round worms of similar size and body type thrash about, slithering their doughy forms over unpredictable substrates. Yet the water bear, a micro-animal so distinct that scientists were forced to assign it to its own phylum, uses eight stubby legs to improbably propel itself through marine and freshwater sediment, across desert dunes, and beneath the soil.

Now, a new study in PNAS analyzes tardigrade gaits and finds that water bears walk in a manner most closely resembling that of insects 500,000 times their size. The discovery implies the existence of either a common ancestor or an evolutionary advantage that explains why one of the smallest and squishiest creatures evolved to walk just like larger, hard-bodied insects.

"Tardigrades have a robust and clear way of moving -- they're not these clumsy things stumbling around in the desert or in leaf litter," says Jasmine Nirody, a fellow in Rockefeller's Center for Studies in Physics and Biology. "The similarities between their locomotive strategy and that of much larger insects and arthropods opens up several very interesting evolutionary questions."

Smooth runners

Nirody and colleagues first determined how water bears walk and run. "If you watch tardigrades under a light microscope for long enough, you can capture a wide range of behavior," Nirody says. "We didn't force them to do anything. Sometimes they would be really chill and just want to stroll around the substrate. Other times, they'd see something they like and run towards it."

Nirody found that, at their most leisurely, water bears lumber about half a body length per second. At full throttle, their loping strides carried them two body lengths in the same amount of time. But the surprise came when she observed how a water bear's feet contact the ground as it gains momentum. Unlike vertebrates, which have distinct gaits for each speed -- picture a horse's hooves as it transitions from a walk to a gallop -- tardigrades run more like insects, scurrying at increasing speeds without ever changing their basic stepping patterns.

"When vertebrates switch from walking to running, there is a discontinuity," Nirody says. "With arthropods, all stepping patterns exist along the same continuum."

Ancient coordination

Why do tardigrades share a locomotive strategy with much larger, hard-bodied insects?

One possible explanation is that tardigrades, long assumed to fit neatly into no existing taxonomy, may share common ancestors -- and even a common neural circuit -- with insects such as fruit flies, ants, and other segmented scurrying creatures. In fact, some scientists advocate classifying tardigrades within the proposed panarthropod clade, a catchall group that would assign common shelf space to insects, crustaceans, velvet worms, and water bears.

Another possibility is that there is no ancestral connection between tardigrades and arthropods, but that the unrelated groups of organisms independently arrived at the same walking and running strategies because they were evolutionarily advantageous. Perhaps the best way to navigate unpredictable terrain with a microscopic body is to plod like a water bear.

Nirody is equally fascinated by both possibilities. "If there is some ancestral neural system that controls all of panarthropod walking, we have a lot to learn," she says. "On the other hand, if arthropods and tardigrades converged upon this strategy independently, then there's much to be said about what makes this strategy so palatable for species in different environments."

Beyond the implications for evolutionary biology and the study of animal locomotion, the findings may have ramifications for the burgeoning fields of soft and microscale robotics.

By studying how small animals evolved to move across challenging environments, scientists may be able to design robots that can more efficiently squeeze into small spaces or operate at the microscale. "We don't know much about what happens at the extremes of locomotion -- how to make an efficient small walker, or how soft-bodied things should move," Nirody says.

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Oxygen-delivering hydrogel accelerates diabetic wound healing

About one-fourth of people with diabetes develop painful foot ulcers, which are slow to heal due to low oxygen in the wound from impaired blood vessels and increased inflammation. These wounds can become chronic, leading to poor quality of life and potential amputation.

Jianjun Guan, a professor of mechanical engineering & materials science in the McKelvey School of Engineering at Washington University in St. Louis, has developed a hydrogel that delivers oxygen to a wound, which decreases inflammation, helps remodel tissue and accelerates healing. Results of the work, which were in a mouse model, are published Aug. 28 in Science Advances. Ya Guan, a doctoral student, and Hong Niu, a postdoctoral research associate, both in Guan's lab, are co-first authors.

"The oxygen has two roles: one, to improve skin cell survival under the low-oxygen condition of the diabetic wound; and two, oxygen can stimulate the skin cells to produce growth factors necessary for wound repair," Guan said.

Tissues in the body require oxygen to survive and need even more when tissue is injured. While there are several existing treatments for chronic wounds in people with diabetes, the most common treatment is dozens of sessions in a hyperbaric oxygen chamber, but its effectiveness is inconsistent and includes the risk of oxygen toxicity.

Guan's hydrogel delivers oxygen to the wound using microspheres that gradually release oxygen to interact with the cells through an enzyme on their surface that converts what is inside of the microsphere into oxygen. The oxygen is delivered to the wound over about a two-week period, and inflammation and swelling decrease, prompting healing.

In the mice, wounds treated with the hydrogel containing the oxygen-releasing microspheres had a greater rate of closure than wounds treated with only the gel or those with no treatment. By day 16, the wounds treated with the hydrogel had reduced to 10.7%. Those treated with the gel only were reduced to 30.4%, and those with no treatment had reduced to 52.2%.

In addition, the wounds treated with the hydrogel containing the oxygen-releasing microspheres had the thickest epidermis on day 8, but the thinnest by day 16, indicating the wound was healing and inflammation was reduced.

Over the past 14 years, Guan has been developing this type of gel, which has nearly 70 different functions and chemical structures.

"The gel is a liquid before we put it into the skin tissue, so it is easy to mix in the microspheres," he said. "Once we put the mixture of the gel and the microspheres into the wound, it becomes a solid because it is temperature-sensitive -- at lower temperatures it is a liquid, and at body temperature it's a solid."

One risk of delivering oxygen to wounds is delivering too much, which creates reactive oxygen species (ROS), which can damage or kill cells at elevated levels. Guan's hydrogel is able to scavenge for ROS content and destroy it, eliminating any risk.

Next, Guan's team plans to use the hydrogel in a large animal model with the expectation of future human clinical trials.

"This represents a new therapeutic approach to accelerating healing of chronic diabetic wounds without drugs," Guan said. "It also has the potential to treat other diseases in which oxygen is low, such as peripheral artery disease and coronary heart disease."

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Dogs tell the difference between intentional and unintentional action

Over our long shared history, dogs have developed a range of skills for bonding with human beings. Their ability to make sense of human actions, demonstrated by every "sit," "lay down," and "roll over," is just one such skill. But whether dogs understand human intentions, or merely respond to outcomes, remains unclear. The ability to recognize another's intentions -- or at least conceive of them -- is a basic component of Theory of Mind, the ability to attribute mental states to oneself and others, long regarded as uniquely human. Do dogs have this basic component of Theory of Mind, the ability to tell the difference between something done on purpose and something done by accident?

To answer this question, a team of researchers in Germany conducted an experiment that examined how dogs reacted when food rewards were withheld, both intentionally and unintentionally. They found that dogs respond differently depending on whether the actions of the experimenter were intentional or unintentional. This, the researchers say, shows that dogs can distinguish between actions that were done on purpose or accidentally.

To reach their conclusions, the researchers conducted an experiment using the "unable vs. unwilling" paradigm. This works by examining whether test subjects react differently towards a human experimenter who either intentionally (the unwilling condition) or unintentionally (the unable condition) withholds rewards from them. Despite being an established paradigm in studies of human and animal cognition, the unable vs. unwilling paradigm had never been previously used to investigate dogs.

The experiment was conducted with 51 dogs, each of which was tested under three conditions. In each condition, the dog was separated from the human tester by a transparent barrier. The basic situation was that the experimenter fed the dog pieces of dog food through a gap in the barrier. In the "unwilling" condition, the experimenter suddenly withdrew the reward through the gap in the barrier and placed it in front of herself. In the "unable-clumsy" condition, the experimenter brought the reward to the gap in the barrier and "tried" to pass it through the gap but then "accidentally" dropped it. In the "unable-blocked" condition, the experimenter again tried to give the dog a reward, but was unable to because the gap in the barrier was blocked. In all conditions, the reward remained on the tester's side of the barrier.

"If dogs are indeed able to ascribe intention-in-action to humans," says Dr. Juliane Bräuer, "we would expect them to show different reactions in the unwilling condition compared to the two unable conditions. As it turns out, this is exactly what we observed."

The primary behaviour measured by the researchers was the time dogs waited before approaching the reward they were denied. The researchers predicted that, if dogs are able to identify human intentions, they would wait longer before approaching the reward in the unwilling condition, where they were not supposed to have the reward, than in the two unable conditions in which the reward was, in fact, meant for them.

Not only did the dogs wait longer in the unwilling condition than in the unable conditions, they were also more likely to sit or lie down -- actions often interpreted as appeasing behaviours -- and stop wagging their tails.

"The dogs in our study clearly behaved differently depending on whether the actions of a human experimenter were intentional or unintentional," says Britta Schünemann, the first author of the study. "This suggests that dogs may indeed be able to identify humans' intention-in-action," adds Hannes Rakoczy from the University of Göttingen.

The team acknowledges that their findings may be met with scepticism and that further study is needed to address alternative explanations, such as behavioural cues on the part of experimenters or knowledge transfer from prior dog training.

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Exploring the past: Computational models shed new light on the evolution of prehistoric languages

A new linguistic study sheds light on the nature of languages spoken before the written period, using computational modeling to reconstruct the grammar of the 6500-7000 year-old Proto-Indo-European language, which is the ancestor of most languages of Eurasia, including English and Hindi. The model employed makes it possible to observe evolutionary trends in language over the millennia. The article, "Reconstructing the evolution of Indo-European grammar," authored by Gerd Carling (Lund University) and Chundra Cathcart (University of Zurich) will be published in the September 2021 issue of the scholarly journal Language.

In the article, Carling & Cathcart use a database of features from 125 different languages of the Indo-European family, including extinct languages such as Sanskrit and Latin. Features include most of the differences that make the languages difficult to learn, such as differentiation in word order (the girl throws the stone in English or caitheann an cailín an chloch "throws the girl the stone" in Irish), gender (the apple in English or der Apfel in German), number of cases, number of forms of the verb, or whether languages have prepositions or postpositions (to the house in English but ghar ko "house-to" in Hindi). With the aid of methods adopted from computational biology, the authors use known grammars to reconstruct grammars of unknown prehistorical periods.

The reconstruction of Indo-European grammar has been the subject of lengthy discussion for over a century. In the 19th century, scholars held the view that the ancient written languages, such as Classical Greek, were most similar to the reconstructed Proto-Indo-European language. The discovery of the archaic but highly dissimilar Hittite language in the early 20th century shifted the focus. Instead, scholars believed that Proto-Indo-European was a language with a structure more similar to non-Indo-European languages of Eurasia such as Basque or languages of the Caucasus region.

The study confirms that Proto-Indo-European was similar to Classical Greek and Sanskrit, supporting the theory of the 19th century scholars. However, the study also provides new insights into the mechanisms of language change. Some features of the proto-language were very stable and dominant over time. Moreover, features of higher prominence and frequency were less likely to change.

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Do genetics control who our friends are? It seems so with mice

Have you ever met someone you instantly liked, or at other times, someone who you knew immediately that you did not want to be friends with, although you did not know why?

Popular author Malcolm Gladwell examined this phenomenon in his best-selling book, Blink. In his book, he noted that an "unconscious" part of the brain enables us to process information spontaneously, when, for example, meeting someone for the first time, interviewing someone for a job, or faced with making a decision quickly under stress.

Now, a new study from the University of Maryland School of Medicine (UMSOM) suggests that there may be a biological basis behind this instantaneous compatibility reaction. A team of researchers showed that variations of an enzyme found in a part of the brain that regulates mood and motivation seems to control which mice want to socially interact with other mice -- with the genetically similar mice preferring each other.

The UMSOM researchers, led by Michy Kelly, PhD, Associate Professor of Anatomy and Neurobiology, say their findings may indicate that similar factors could contribute to the social choices people make. Understanding what factors drive these social preferences may help us to better recognize what goes awry in diseases associated with social withdrawal, such as schizophrenia or autism, so that better therapies can be developed.

The study was published on July 28 in Molecular Psychiatry, a Nature publication.

"We imagine that this is only the first among many biomarkers of compatibility in the brain that may control social preferences," said Dr. Kelly. "Imagine the possibilities of truly understanding the factors behind human compatibility. You could better match relationships to reduce heartache and divorce rates, or better match patients and doctors to advance the quality of healthcare, as studies have shown compatibility can improve health outcomes."

A succession of unlikely events and circumstances over the years eventually culminated in this research project, according to Dr. Kelly.

While she was working at a pharmaceutical company, a group of bone researchers asked Dr. Kelly to characterize the behavior of one of their mutant mice that was missing the PDE11 protein. She observed that these mice without PDE11 withdrew socially, so she knew that PDE11 had to be in the brain. She remembered a study that used a mouse model of schizophrenia in which the researchers damaged the brain's hippocampus leading to antisocial behavior. She then looked at this part of the brain in healthy mice and found where the PDE11 protein was hiding.

Later, as a faculty member at University of South Carolina, she continued studying the social behavior of mutant mice in terms of their social reactions to scent. In the lab, researchers took wooden beads rubbed all over with pungent, airborne pheromones from one group of mice, and placed them in an enclosure with a second group. A mouse presented with one bead from a familiar friend and another from a new stranger mouse would typically spend more time investigating the bead with the stranger's scent on it. When researchers looked at the PDE11 mutant's preferences, they favored the stranger's scent one hour or one week after meeting their friend, but one day after meeting -- considered recent long-term memory for a mouse -- their social memory seemed fuzzy, and they did not differentiate between a friend and a stranger. To the researchers this meant, the mice's short and long-term social memory worked fine, but there was a problem coding the information into recent long-term memory -- the time between short and long-term memory. Given more time, they would eventually recover that memory.

A student working in the laboratory offhandedly remarked that he noticed children with autism prefer to interact with others that have autism. So, Dr. Kelly decided they should test to see if the PDE11 mutants and normal mice had a preference with whom they interacted. The researchers found that PDE11 mutants preferred being around other PDE11 mutants over the normal mice, while normal mice also preferred their own genetic type. This discovery held true even when researchers tested other laboratory mouse strains. When they tested another genetic variant of PDE11 with a single change in the DNA code, mice with that genetic variation preferred other mice with the same variant over any others.

"So, what is it that the mice are sensing that determines their friend preferences?" said Dr. Kelly. "We eliminated smell and body movements as contributing factors, but we still have some other ideas to test."

"What this team has done is to establish a paradigm by which researchers can identify the social underpinnings of friendship in animal models," said E. Albert Reece, MD, PhD, MBA, Executive Vice President for Medical Affairs, UM Baltimore, and the John Z. and Akiko K. Bowers Distinguished Professor and Dean, University of Maryland School of Medicine. "This very important finding is just the start, but hopefully will lead to exciting new avenues of biological or social treatments for diseases like schizophrenia or age-related cognitive decline in which severe social avoidance and isolation can reduce a person's quality of life."

Read more at Science Daily

COVID-19 long-haulers at risk of developing kidney damage, disease

Research continues to mount indicating that many people who've had COVID-19 go on to suffer a range of adverse conditions months after their initial infections. A deep dive into federal health data adds to those concerns, pointing to a significant decline in kidney function among those dubbed COVID-19 long-haulers -- and even among those who had mild infections of the virus.

The data, plumbed by researchers at Washington University School of Medicine in St. Louis and the Veterans Affairs St. Louis Health Care System, show that those infected with SARS-CoV-2 are at an increased likelihood of developing kidney damage as well as chronic and end-stage kidney diseases.

The study is published online Sept. 1 in the Journal of the American Society of Nephrology.

Known as the silent killer, kidney dysfunction and disease tend to be free of pain and other symptoms -- so much so that the National Kidney Foundation estimates that 90% of people with ailing kidneys don't know it. Kidney disease affects 37 million people in the U.S. and is one of the nation's leading causes of death.

"Our findings emphasize the critical importance of paying attention to kidney function and disease in caring for patients who have had COVID-19," said senior author Ziyad Al-Aly, MD, an assistant professor of medicine at Washington University. "If kidney care isn't an integral part of COVID-19 post-acute care strategy, then we will miss opportunities to help potentially hundreds of thousands of people who have no idea that their kidney function has declined due to this virus. This is in addition to the millions of Americans who suffer from kidney disease not caused by COVID-19."

The findings coincide with a surge in COVID-19 infections spurred by the delta variant. More than 38 million people have been diagnosed with the virus since the pandemic started.

"Based on our research, we believe that 510,000 of those people who have had COVID-19 may have kidney injury or disease," Al-Aly said.

The researchers analyzed de-identified medical records in a database maintained by the U.S. Department of Veterans Affairs, the nation's largest integrated health-care delivery system. The researchers created a controlled dataset that included health information from more than 1.7 million healthy and COVID-infected veterans from March 1, 2020, through March 15, 2021. Of those veterans, 89,216 had confirmed COVID-19 diagnoses and made it through the acute phase (the first 30 days of the disease).

The COVID-19 patients in the study were mostly men and in their late 60s; however, the researchers also analyzed data that included 151,289 women -- including 8,817 with COVID-19 -- and adults of all ages. Among the COVID-19 patients, 12,376 (13.9%) required hospitalization, including 4,146 (4.6%) who were admitted to intensive care units (ICUs).

"The risk of decreased kidney function is highest among people who were in the ICU; however, it's important to note that the risk extends to all patients, even those who had milder cases of COVID-19," said Al-Aly, who is also director of the Clinical Epidemiology Center and chief of the Research and Education Service at the Veterans Affairs St. Louis Health Care System.

Earlier stages of kidney disease often can be treated with medication.

"It's essential to discover kidney dysfunction before the problem progresses and becomes harder to treat," Al-Aly said. "But kidney problems are silent problems that won't be found until somebody checks the bloodwork. Based on our research, it's especially important that health-care providers do this for people who have had COVID-19. Otherwise, we'll miss a lot of people and, sadly, we'll be dealing with more advanced kidney diseases down the road."

Compared with patients who did not become infected, people who contracted the virus but did not need to be hospitalized for it had a 15% higher risk of suffering from a major adverse kidney event such as chronic kidney disease, a 30% higher risk of developing acute kidney injury, and a 215% (more than twofold) higher risk of acquiring end-stage kidney disease. The latter occurs when the kidneys can no longer effectively remove waste from the body. In such cases, dialysis or a kidney transplant is needed to keep patients alive.

The risk increased for patients hospitalized for COVID-19, and considerably so for those who were in the ICU for the virus: seven times the risk of experiencing a major adverse kidney event, eight times the risk of acute kidney injury and 13 times the risk of end-stage kidney disease.

"People who were hospitalized for COVID-19 or needed ICU care are at the highest risk," Al-Aly said. "But the risk is not zero for those who had milder cases. In fact, it's significant. And we need to remember that we don't yet know the health implications for long-haulers in the coming years."

After the initial 30 days of COVID-19 infection, 4,757 (5.3%) of the patients experienced a decrease of 30% or more in glomerular filtration rates (GFR), which physicians use to assess kidney function and, if applicable, determine the severity of kidney disease. The rate is determined by a simple blood test that measures levels of creatinine, a waste product in the blood that is filtered by the kidneys and discarded into urine.

The researchers found that people who had milder COVID-19 cases had 1.09 times the risk of having an estimated GFR decline of 30% or more. For hospitalized COVID-19 patients not in intensive care units, there was two times the risk of having an estimated GFR decrease of 30% or more, while intensive care unit patients were at three times the risk of experiencing an estimated GFR drop of 30% or more.

"The kidney damage was in excess of reduced function caused by normal aging," Al-Aly explained. "A 60-year-old's kidney function is less robust than the kidneys of a 20-year-old. The kidney function decline we've observed in these patients is not graceful aging. It is not normal anything. It is definitely a disease state.

Read more at Science Daily

Newly identified mosasaur was fish-hunting monster

Researchers at the University of Cincinnati identified a new species of mosasaur -- an 18-foot-long fish-eating monster that lived 80 million years ago.

UC assistant professor-educator Takuya Konishi and his student, UC graduate Alexander Willman, named the mosasaur Ectenosaurus everhartorum after paleontologists Mike and Pamela Everhart. The mosasaur inhabited the Western Interior Seaway in what today is western Kansas.

The discovery was announced this week in the Canadian Journal of Earth Sciences.

The newly identified mosasaur marks only the second species in the genus Ectenosaurus.

"Mosasaurs in western Kansas have been well sampled and well researched. Those two factors create tall odds when you try to find something new," Konishi said.

Mosasaurs were enormous marine reptiles, some as big as school buses. They inhabited oceans around the world during the Cretaceous period around the time of Tyrannosaurus rex. If Ectenosaurus clidastoides with its long, slender jaws resembles a gharial crocodile, Konishi said the new species is closer to a false gharial crocodile with notably blunter jaws.

Konishi, who teaches in the Biological Sciences Department of UC's College of Arts and Sciences, first encountered the fossil in 2004 while working as a graduate student in systematics and evolution. Konishi was studying fossils of Platecarpus, a different genus of mosasaur in storage at Fort Hays State University's Sternberg Museum of Natural History, when he recognized something odd about one specimen.

"It wasn't a platecarpus. The frontal bone above the eye socket was much longer. The bones of Platecarpus should have had a broader triangle," he said. "That was one telltale sign."

Konishi suspected the specimen was a type of ectenosaur, only one species of which had been identified. But the teeth seemed all wrong. The now-empty sockets that would have contained the mosasaur's sharp, curved teeth in the unidentified specimen would have extended around the front of its mouth, unlike other recognized species that has a toothless rostrum, the bony protuberance at the front of the mouth.

For years, the fossils puzzled him.

"Some things just stick in your mind and they're hard to let go," he said.

But the mystery would have to wait because Konishi was busy finishing his doctoral degree and launching an academic career that would bring him to UC's College of Arts and Sciences.

The first mosasaur fossils were found in the Netherlands a half-century before anyone used the term "dinosaur." Mosasaurs began to capture the nation's attention after the Civil War when the nation's premier paleontologists, Othniel Charles Marsh and Edward Drinker Cope, began to study Cretaceous limestone in Kansas in a partnership that became a bitter public feud. Since then, Kansas has become world-renowned for mosasaur research.

Generations of experts have come to Kansas to study its specimens, which are on display at museums around the world.

"It's a famous place for mosasaur research. It's quite well known," Konishi said. "So I thought I don't have to be the guy to place a stake. I'm sure someone will catch it. But nobody did."

Ectenosaur is unusual for how few specimens have been found in the genus compared to other mosasaurs, Konishi said.

"In western Kansas we have over 1,500 mosasaur specimens. Out of those we can only find one specimen each representing these two species of ectenosaur," Konishi said. "That's sort of crazy."

When Konishi confirmed with the Sternberg Museum that no other researchers were studying the specimen, he asked them to ship the fossils to UC. When he opened the carefully bubble-wrapped contents, his initial impressions were confirmed.

"By then I had looked at all the other known Platecarpus specimens under the sun, as it were. And this specimen was distinct from the others," he said. "To me it was so obvious."

At the same time, Konishi's student Willman inquired about working on a research project. He received a UC Undergraduate STEM Experience grant to help with the taxonomic identification.

"I was beyond excited to be part of the discovery," Willman said.

The third author on the study, Michael Caldwell, is a professor of biology at the University of Alberta, Edmonton.

Willman illustrated the fossils in painstaking detail to help scientists understand the morphological differences that make the mosasaur unique.

"I was very happy with how he brought these broken bones to life," Konishi said. "It helped make our case very convincing to anyone that this is something new that warrants the establishment of a new taxon."

The researchers dedicated the project to the late Dale Russell, whose work has had a profound impact in North American mosasaur paleontology, Konishi said. But they named the mosasaur for the Everharts, a Kansas couple who have spent more than 30 years sharing their fossils with museums and leading research field trips in the fossil-rich Smoky Hill Chalk.

"We're still in a little bit of shock at the news. It's very exciting," Pamela Everhart said.

"It's a great honor," said Mike Everhart, author of "Oceans of Kansas" about mosasaurs and other prehistoric life that inhabited the Western Interior Seaway during the Cretaceous Period.

Mosasaurs are very special to him, he said.

Read more at Science Daily

How people respond to wildfire smoke

As wildfires become commonplace in the western U.S. and around the world, checking the daily air quality warning has become as routine as checking the weather. But what people do with that data -- whether it drives them to slip on a mask before stepping outside or seal up their homes against smoke -- is not always straightforward or rational, according to new Stanford research.

In a case study of Northern California residents, Stanford researchers explored the psychological factors and social processes that drive responses to wildfire smoke. The research, which ultimately aims to uncover approaches for helping people better protect themselves, shows that social norms and social support are essential for understanding protective health actions during wildfire smoke events. The findings appeared this month in the journal Climate Risk Management.

"It's important to understand how people behave so that public health communications professionals can potentially intervene and promote safer behavior that mitigates risk," said lead study author Francisca Santana, a PhD student in the Emmett Interdisciplinary Program in Environment and Resources (E-IPER). "This kind of qualitative work is a first step so that we can learn how people are using information and interacting to make decisions. We can then look at where there might be leverage points or opportunities to promote more protective behavior."

Exposure to wildfire smoke can irritate the lungs, cause inflammation, impact the immune system and increase susceptibility to lung infections, including the virus that causes COVID-19, according to the Centers for Disease Control and Prevention. While other studies have examined how people respond to evacuation orders, little has been done to understand what's happening with wildfire smoke exposure if people don't -- or can't -- leave the area, according to senior study author Gabrielle Wong-Parodi, an assistant professor of Earth system science at Stanford's School of Earth, Energy & Environmental Sciences (Stanford Earth).

"It resonated with me, the things that people were doing to try to protect themselves in the absence of access to effective ways to reduce their wildfire smoke exposure," Wong-Parodi said, referring to a resident who breathed through a wet bandana in an attempt to filter out toxic smoke particles. "It's urgent that we come up with strategies that are realistic for what people are going through."

Study authors Santana and David Gonzalez, who worked on the study as a PhD student at Stanford, interviewed residents across age, race and income demographics who were affected by wildfire smoke from the 2018 Camp Fire that destroyed Paradise, California, and subsequent fires in 2019 in Fresno, Santa Clara and Sacramento counties.

They found that individuals responded to wildfire smoke events in three main ways: interpreting information together, protecting vulnerable others and questioning protective actions. Their responses were influenced not only by the Air Quality Index (AQI) but also by what they were personally experiencing -- whether they smelled, saw or tasted smoke in the air.

Just as important were the social factors at play, the researchers found. "Social norms and social support were really influencing how people chose to act on their perceptions of threat," Santana said. "For example, a lot of people talked about observing others wearing masks, and in some cases that observation was enough for them to act by wearing a mask themselves."

Their discussions revealed that the shared rules or standards of behavior within a social group -- social norms -- were a common pathway driving behavior change, in addition to the act of assisting or comforting others within your social group -- social support.

"There were only a handful of people who described looking at the AQI and then changing their behavior based on just that -- it was almost always a conversation they were having with one another," Santana said. "It was very much a social exercise of making sense of limited information or information that was not at the right scale for their community."

The study provides a framework for better understanding wildfire smoke responses by examining social processes while acknowledging that cultural and political contexts, as well as factors like demographics, health status and previous exposure to smoke and air pollution, may also influence individual behaviors.

In the western U.S., climate change has contributed to the risk and extent of wildfires, bringing smoke to regions like the Bay Area, which has historically been less affected than the rest of the state. In some cases, the researchers found that residents were unable to protect themselves because they couldn't access N95 masks or air purifiers or properly seal their homes.

"This research is also important for epidemiologists trying to understand how wildfire smoke affects health," said Gonzalez, who is now a postdoctoral researcher at the University of California, Berkeley. "This can help us to look at disparities in who's exposed to smoke and whether that leads to poorer health for some populations."

As these events become more common, there could be an opportunity to find policy synergies that help prepare communities for future smoke events, according to the co-authors. For example, programs that are designed to improve household comfort and increase energy efficiency could also include measures to reduce smoke intrusion during wildfire smoke events, Wong-Parodi suggested.

Some of the interviews revealed that residents simply didn't know what to do while experiencing a novel extreme event. But even that revealed how processing uncertainty is a social exercise, not just a cognitive one.

Read more at Science Daily

Learning from a 'living fossil'

As we live and breathe, ancient-looking fish known as bowfin are guarding genetic secrets that that can help unravel humanity's evolutionary history and better understand its health.

Michigan State researchers Ingo Braasch and Andrew Thompson are now decoding some of those secrets. Leading a project that included more than two dozen researchers spanning three continents, the Spartans have assembled the most complete picture of the bowfin genome to date.

"For the first time, we have what's called a chromosome-level genome assembly for the bowfin," said Braasch, an assistant professor of integrative biology in the College of Natural Science. "If you think of the genome like a book, what we had in the past was like having all the pages ripped out in pieces. Now, we've put them back in the book."

"And in order," added Thompson, a postdoctoral researcher in Braasch's lab and the first author of the new research report, published Aug. 30 in the journal Nature Genetics.

This is really important information for a few reasons, the duo said, and it starts with the bowfin being what Charles Darwin referred to as a "living fossil." The bowfin, or dogfish, looks like an ancient fish.

This doesn't mean that the bowfin hasn't evolved since ancient times, but it has evolved more slowly than most fishes. This means that the bowfin has more in common with the last ancestor shared by fish and humans, hundreds of millions of years ago, than, say, today's zebrafish.

Zebrafish -- which are modern, so-called teleost fishes -- are a notable example because they're widely used by scientists as a model to test and develop theories about human health. Having more genetic information about the bowfin helps make the zebrafish a better model.

"A lot of research on human health and disease is done on model organisms, like mice and zebrafish," Thompson said. "But once you identify important genes and the elements that regulate those genes in zebrafish, it can be hard to find their equivalents in humans. It's easier to go from zebrafish to bowfin to human."

For example, one particularly interesting gene is one that's used in developing the bowfin's gas bladder, an organ the fish uses to breathe and store air. Scientists believe that the last common ancestor shared by fish and humans had air-filled organs like these that were evolutionary predecessors to human lungs.

In their new study, the Spartan researchers could see that a certain genetic process in the bowfin's gas bladder development bore striking similarities to what's known about human lung development. A similar process is also present in the modern teleost fishes, but it's been obscured by eons of evolution.

"When you looked for the human genetic elements of this organ development in zebrafish, you couldn't find it because teleost fishes have higher rates of evolution," Thompson said. "It's there in modern fishes, but it's hidden from view until you see it in bowfin and gar."

The gar is another air-breathing fish with "living fossil" status that's studied by Braasch and his team. With both the gar and bowfin genomes, the team was able to show where these genetic elements linked to gas bladder and lung formation were hiding out in the modern teleost fishes. The ancient fish enable researchers to build a better bridge between the established modern fish model organisms and human biology.

"You don't want to base that bridge on one species," said Braasch, who added this finding also strengthens the implications for evolutionary history. "This is another piece of the puzzle that suggests the common ancestor of fish and humans had an air-filled organ and used it for breathing at the water surface, quite similar to what you see in bowfin and gar."

Although these findings have insights that are pertinent to all of humanity, Spartans might feel a special affinity for the bowfin. For starters, male fish turn their fins and throats a bright shade of green during spawning season. Also, famed biologist William Ballard of Dartmouth College studied bowfin development from eggs to larval fish at Michigan State's W.K. Kellogg Biological Station during the 1980s. This was what he called his "Odyssey of Strange Fish," and Braasch's team now uses his work to guide their genomic analyses of bowfin development.

Bowfins are native to Michigan. They could be in the Red Cedar River on MSU's campus now, according to Thompson, but they also can be quite elusive and, sometimes, very aggressive. This made collaborations essential for securing specimens. With colleagues at Nicholls State University in Louisiana, the team caught bowfins for genome sequencing. Amy McCune, a collaborator and professor at Cornell University, knew where to find bowfin eggs in upstate New York and had a graduate student gifted at securing these unique samples for investigating bowfin development.

The Spartans also had connections at other universities and institutions with experts in bowfin biology, chromosome evolution and more. All told, the team included researchers from six states as well as France, Japan and Switzerland. Back in East Lansing, graduate students Mauricio Losilla and Olivia Fitch, research technologist Brett Racicot, and Kevin Childs, director of the MSU Genomics Core facility, also contributed to the study, which comes with an interesting twist at the end.

Almost all vertebrate creatures that grow paired limbs or fins share a common gene.

"Humans use it, mice use it. All fishes that have been studied so far use it," Braasch said. "The naïve expectation would be that bowfin do, too."

But that's not what the team found. The bowfin, the "living fossil," has evolved a different way of growing its paired fins.

Read more at Science Daily

Perceptions of supernatural beings reveal feelings about good and bad in humans

What transpires in comedies and cartoons when a character has a devil on one shoulder and an angel on the other is not far off from people's perceptions of the real world, finds a new study from the University of Waterloo.

Intended to illustrate the characters' decision-making dilemma with comedic results, the moral character and motives of the supernatural beings are obvious. And people have similar expectations when it comes to individuals they see as good or bad.

The researchers explored expectations about how good and evil individuals respond to requests. The researchers were interested in understanding why movies and folktales often depict the devil and demons as eager to grant accidental requests, whereas angels are not depicted this way.

Their study indicates that people's beliefs about good and evil characters are influenced by their views of ordinary humans.

"Our results suggest people expect good agents will be sensitive to intentions behind requests whereas they expect evil individuals will be relatively insensitive to these intentions," said Ori Friedman, developmental psychology professor at Waterloo and lead author of the study. "These findings shape people's expectations about requests directed both to regular humans and to supernatural agents."

The study shows that people have distinct ideas of how being good or bad influences the decisions of others. People assume that evil individuals are indifferent about anything that doesn't directly impact their own aims.

These findings support previous research in suggesting that at least some of people's everyday beliefs about supernatural beings could be based on their views of humans.

"One aspect of seeing someone as evil might be that we expect that person to put less emphasis on the intentions of others, and instead focus more on the outcome of people's actions," says Brandon Goulding, a PhD candidate in developmental psychology and co-author of the study. "Whereas we think that a good person will also consider what someone meant to do, and weigh that against what they actually did."

Researchers investigated people's expectations about good and evil agents with five experiments. In the study, 2,231 participants read short stories about a protagonist's request to either a human or supernatural being and rated the likelihood the request would be granted. When the request was directed to someone good, ratings depended on whether the requester actually understood what they were requesting. Evil individuals were expected to grant requests just as often when they were confused and didn't reflect the requester's intentions.

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New mathematical solutions to an old problem in astronomy

For millennia, humanity has observed the changing phases of the Moon. The rise and fall of sunlight reflected off the Moon, as it presents its different faces to us, is known as a "phase curve." Measuring phase curves of the Moon and Solar System planets is an ancient branch of astronomy that goes back at least a century. The shapes of these phase curves encode information on the surfaces and atmospheres of these celestial bodies. In modern times, astronomers have measured the phase curves of exoplanets using space telescopes such as Hubble, Spitzer, TESS and CHEOPS. These observations are compared with theoretical predictions. In order to do so, one needs a way of calculating these phase curves. It involves seeking a solution to a difficult mathematical problem concerning the physics of radiation.

Approaches for the calculation of phase curves have existed since the 18th century. The oldest of these solutions goes back to the Swiss mathematician, physicist and astronomer, Johann Heinrich Lambert, who lived in the 18th century. "Lambert's law of reflection" is attributed to him. The problem of calculating reflected light from Solar System planets was posed by the American astronomer Henry Norris Russell in an influential 1916 paper. Another well-known 1981 solution is attributed to the American lunar scientist Bruce Hapke, who built on the classic work of the Indian-American Nobel laureate Subrahmanyan Chandrasekhar in 1960. Hapke pioneered the study of the Moon using mathematical solutions of phase curves. The Soviet physicist Viktor Sobolev also made important contributions to the study of reflected light from celestial bodies in his influential 1975 textbook. Inspired by the work of these scientists, theoretical astrophysicist Kevin Heng of the Center for Space and Habitability CSH at the University of Bern has discovered an entire family of new mathematical solutions for calculating phase curves. The paper, authored by Kevin Heng in collaboration with Brett Morris from the National Center of Competence in Research NCCR PlanetS -- which the University of Bern manages together with the University of Geneva -- and Daniel Kitzmann from the CSH, has just been published in Nature Astronomy.

Generally applicable solutions

"I was fortunate that this rich body of work had already been done by these great scientists. Hapke had discovered a simpler way to write down the classic solution of Chandrasekhar, who famously solved the radiative transfer equation for isotropic scattering. Sobolev had realised that one can study the problem in at least two mathematical coordinate systems." Sara Seager brought the problem to Heng's attention by her summary of it in her 2010 textbook.

By combining these insights, Heng was able to write down mathematical solutions for the strength of reflection (the albedo) and the shape of the phase curve, both completely on paper and without resorting to a computer. "The ground-breaking aspect of these solutions is that they are valid for any law of reflection, which means they can be used in very general ways. The defining moment came for me when I compared these pen-and-paper calculations to what other researchers had done using computer calculations. I was blown away by how well they matched," said Heng.

Successful analysis of the phase curve of Jupiter

"What excites me is not just the discovery of new theory, but also its major implications for interpreting data," says Heng. For example, the Cassini spacecraft measured phase curves of Jupiter in the early 2000s, but an in-depth analysis of the data had not previously been done, probably because the calculations were too computationally expensive. With this new family of solutions, Heng was able to analyze the Cassini phase curves and infer that the atmosphere of Jupiter is filled with clouds made up of large, irregular particles of different sizes. This parallel study has just been published by the Astrophysical Journal Letters, in collaboration with Cassini data expert and planetary scientist Liming Li of Houston University in Texas, U.S.A.

New possibilities for the analysis of data from space telescopes

"The ability to write down mathematical solutions for phase curves of reflected light on paper means that one can use them to analyze data in seconds," said Heng. It opens up new ways of interpreting data that were previously infeasible. Heng is collaborating with Pierre Auclair-Desrotour (formerly CSH, currently at Paris Observatory) to further generalize these mathematical solutions. "Pierre Auclair-Desrotour is a more talented applied mathematician than I am, and we promise exciting results in the near future," said Heng.

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Common pesticide may contribute to global obesity crisis

A commonly-used pesticide could be partially responsible for the global obesity epidemic, says a study led by McMaster University scientists.

Researchers discovered that chlorpyrifos, which is banned for use on foods in Canada but widely sprayed on fruits and vegetables in many other parts of the world, slows down the burning of calories in the brown adipose tissue of mice. Reducing this burning of calories, a process known as diet-induced thermogenesis, causes the body to store these extra calories, promoting obesity.

Scientists made the discovery after studying 34 commonly used pesticides and herbicides in brown fat cells and testing the effects of chlorpyrifos in mice fed high calorie diets. Their findings were published in Nature Communications and could have important implications for public health.

"Brown fat is the metabolic furnace in our body, burning calories, unlike normal fat that is used to store them. This generates heat and prevents calories from being deposited on our bodies as normal white fat. We know brown fat is activated during cold and when we eat," said senior author Gregory Steinberg, professor of medicine and co-director of the Centre for Metabolism, Obesity, and Diabetes Research at McMaster.

"Lifestyle changes around diet and exercise rarely lead to sustained weight loss. We think part of the problem may be this intrinsic dialling back of the metabolic furnace by chlorpyrifos."

Steinberg said chlorpyrifos would only need to inhibit energy use in brown fat by 40 calories every day to trigger obesity in adults, which would translate to an extra five lbs of weight gain per year.

He said that while several environmental toxins including chlorpyrifos have been linked to rising obesity rates in both humans and animals, most of these studies have attributed weight gain to increases in food intake and not the burning of calories.

While the use of chlorpyrifos on foods is banned in Canada, imported produce may still be treated with it.

"Although the findings have yet to be confirmed in humans, an important consideration, is that whenever possible consume fruits and vegetables from local Canadian sources and if consuming imported produce, make sure it is thoroughly washed," said Steinberg.

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Insights into how a stroke affects reading could help with rehabilitation

Georgetown University researchers, looking at the ability of people to sound out words after a stroke, found that knowing which region of the brain was impacted by the stroke could have important implications for helping target rehabilitation efforts.

The finding appeared August 30, 2021, in Brain Communications.

"One in five stroke survivors in the United States live with persistent language impairment. Most of these people also struggle with reading," says the study's first author, J. Vivian Dickens, PhD, a Georgetown University MD/PhD student conducting research in the university's Cognitive Recovery Lab and Center for Aphasia Research and Rehabilitation at Georgetown's Medical Center. "Our study clarifies the neuroanatomical and cognitive bases of post-stroke reading and language deficits, which could help facilitate predictions of deficits in stroke survivors and suggest targeted treatments."

The research focus was on phonological processing, which is understanding and being able to use the sounds that comprise language. There are three principal aspects to this processing: auditory, or the ability to recognize the sounds of words, such as judging if words rhyme; motor, which is the ability to produce accurate and clear speech; and auditory-motor translation, which is the translation of sounds heard into speech.

"The goal of this study was to understand how post-stroke difficulties with the three different aspects of phonology relate to difficulties with reading," says Dickens. "There are two broad ways that people read words: one involves sounding out words, which is particularly important for reading new words; the other involves whole-word recognition. People with post-stroke language impairment frequently have specific trouble sounding out words."

The investigators tested reading and phonological abilities in 67 people, 30 of whom had had a stroke and 37 that had not. Advanced MRI techniques allowed the researchers to trace out white matter connections, which are akin to wiring diagrams for the brain, as well as map out stroke locations in the brains of affected study participants.

"We found two different patterns of reading problems. Strokes involving the left frontal lobe caused problems with motor phonology and one of the two ways of reading, specifically sounding out words. In contrast, strokes involving the left temporal and parietal lobes caused problems with auditory-motor translation and both ways of reading," says Dickens. "These results may help clinicians develop therapies focused on specific reading problems that individual stroke survivors often struggle with."

"This study focused on reading aloud single words, a classic measure of reading ability," says Peter E. Turkeltaub, MD, PhD, director of the Cognitive Recovery Lab in the Center for Brain Plasticity and Recovery, medical director in the Center for Aphasia Research and Rehabilitation and senior author of the article. "Our results are an important step forward in revealing the mechanisms of translating print to sound, which is crucial for developing rehabilitative therapies for patients who have had strokes."

The investigators are planning studies to help confirm the extent to which these findings can be generalized to silent reading, which relies on the same core psychological processes as oral reading and is more important for reading in daily life. The researchers are also hoping to turn their research tasks into useful clinical tests to diagnose phonological processing.

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Unease beyond the uncanny valley: How people react to the same faces

Increasingly, movies featuring humanoid robots, like Terminator or Ex Machina, are showing the titular "robot" akin to humans not only in intelligence but also appearance. What if Terminator-esque robots became the norm, making it difficult for us to tell them apart from actual human beings?

This is the premise of a new study published in PLOS ONE, which evaluated how human beings respond to images of people with the same face. It is not too far-fetched to imagine a future where human-like androids are mass-produced and are indistinguishable from flesh-and-blood human beings. Robotics and artificial intelligence are advancing at an unprecedented rate, with very closely human-like robots and CG characters, such as Geminoid, Saya, and Sophia already having been produced. Developers are optimistic they will one day create robots that surpass the uncanny valley -- a well-known phenomenon where humanoids elicit unpleasant and negative emotions in viewers when their appearance becomes similar to that of humans.

In such a future, how would we react?

A team of researchers from Kyushu University, Ritsumeikan University, and Kansai University, collaboratively conducted a series of six experiments involving different batches of hundreds of people to try and find that answer.

The first experiment involved rating the subjective eeriness, emotional valence, and realism of a photoshopped photograph of six human subjects with the exact same face (clone image), six people with different faces (non-clone image), and one person (single image). The second experiment comprised rating another set of clone images and non-clone images, while the third experiment consisted of rating clone and non-clone images of dogs. The fourth experiment had two parts: rating clone images of two sets of twins and then rating clone faces of twins, triplets, quadruplets, and quintuplets. The fifth experiment involved clone images of Japanese animation and cartoon characters. And the sixth and final experiment involved evaluating the subjective eeriness and realism of a different set of clone and non-clone images while also answering the Disgust Scale Revised to analyze disgust sensitivity.

The results were striking. Participants from the first study rated individuals with clone faces as eerier and more improbable than those with different faces and a single person's face.

The researchers termed this negative emotional response as the clone devaluation effect.

"The clone devaluation effect was stronger when the number of clone faces increased from two to four," says lead author Dr. Fumiya Yonemitsu from Graduate School of Human-Environment Studies at Kyushu University, who is also a Research Fellow of Japan Society for the Promotion of Science. "This effect did not occur when each clone face was indistinguishable, like animal faces in experiment three involving dogs."

According to him, "We also noticed that the duplication of identity, that is the personality and mind unique to a person, rather than their facial features, has an important role in this effect. Clone faces with the duplication of identity were eerier, as the fourth experiment showed. The clone devaluation effect became weaker when clone faces existed in the lower reality of the context, such as in the fifth experiment. Furthermore, the eeriness of clone faces stemming from improbability could be positively predicted by disgust, in particular animal-reminder disgust, as noticed in the sixth experiment. Taken together, these results suggest that clone faces induce eeriness and that the clone devaluation effect is related to realism and disgust reaction."

These results show that human faces provide important information for identifying individuals because human beings have a one-to-one correspondence between face and identity. Clone faces violate this principle, which may make humans misjudge the identity of people with clone faces as being the same.

So, what does this mean for a future in which humanoids are inevitable? According to the researchers, we need to think critically about introducing new technology in robotics or human cloning because of the potential for unpleasant psychological reactions other than the uncanny valley phenomenon.

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Unravelling the mystery of brown dwarfs

Brown dwarfs are astronomical objects with masses between those of planets and stars. The question of where exactly the limits of their mass lie remains a matter of debate, especially since their constitution is very similar to that of low-mass stars. So how do we know whether we are dealing with a brown dwarf or a very low mass star? An international team, led by scientists from the University of Geneva (UNIGE) and the Swiss National Centre of Competence in Research (NCCR) PlanetS, in collaboration with the University of Bern, has identified five objects that have masses near the border separating stars and brown dwarfs that could help scientists understand the nature of these mysterious objects. The results can be found in the journal Astronomy & Astrophysics.

Like Jupiter and other giant gas planets, stars are mainly made of hydrogen and helium. But unlike gas planets, stars are so massive and their gravitational force so powerful that hydrogen atoms fuse to produce helium, releasing huge amounts of energy and light.

'Failed stars'

Brown dwarfs, on the other hand, are not massive enough to fuse hydrogen and therefore cannot produce the enormous amount of light and heat of stars. Instead, they fuse relatively small stores of a heavier atomic version of hydrogen: deuterium. This process is less efficient and the light from brown dwarfs is much weaker than that from stars. This is why scientists often refer to them as 'failed stars'.

"However, we still do not know exactly where the mass limits of brown dwarfs lie, limits that allow them to be distinguished from low-mass stars that can burn hydrogen for many billions of years, whereas a brown dwarf will have a short burning stage and then a colder life," points out Nolan Grieves, a researcher in the Department of Astronomy at the UNIGE's Faculty of Science, a member of the NCCR PlanetS and the study's first author. "These limits vary depending on the chemical composition of the brown dwarf, for example, or the way it formed, as well as its initial radius," he explains. To get a better idea of what these mysterious objects are, we need to study examples in detail. But it turns out that they are rather rare. "So far, we have only accurately characterised about 30 brown dwarfs," says the Geneva-based researcher. Compared to the hundreds of planets that astronomers know in detail, this is very few. All the more so if one considers that their larger size makes brown dwarfs easier to detect than planets.

New pieces to the puzzle

Today, the international team characterized five companions that were originally identified with the Transiting Exoplanet Survey Satellite (TESS) as TESS objects of interest (TOI) -- TOI-148, TOI-587, TOI-681, TOI-746 and TOI-1213. These are called 'companions' because they orbit their respective host stars. They do so with periods of 5 to 27 days, have radii between 0.81 and 1.66 times that of Jupiter and are between 77 and 98 times more massive. This places them on the borderline between brown dwarfs and stars.

These five new objects therefore contain valuable information. "Each new discovery reveals additional clues about the nature of brown dwarfs and gives us a better understanding of how they form and why they are so rare," says Monika Lendl, a researcher in the Department of Astronomy at the UNIGE and a member of the NCCR PlanetS.

One of the clues the scientists found to show these objects are brown dwarfs is the relationship between their size and age, as explained by François Bouchy, professor at UNIGE and member of the NCCR PlanetS: "Brown dwarfs are supposed to shrink over time as they burn up their deuterium reserves and cool down. Here we found that the two oldest objects, TOI 148 and 746, have a smaller radius, while the two younger companions have larger radii."

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