Field geology at Mars' equator points to ancient megaflood

 Floods of unimaginable magnitude once washed through Gale Crater on Mars' equator around 4 billion years ago -- a finding that hints at the possibility that life may have existed there, according to data collected by NASA's Curiosity rover and analyzed in joint project by scientists from Jackson State University, Cornell University, the Jet Propulsion Laboratory and the University of Hawaii.

The research, "Deposits from Giant Floods in Gale Crater and Their Implications for the Climate of Early Mars," was published Nov. 5 in Scientific Reports.

The raging megaflood -- likely touched off by the heat of a meteoritic impact, which unleashed ice stored on the Martian surface -- set up gigantic ripples that are tell-tale geologic structures familiar to scientists on Earth.

"We identified megafloods for the first time using detailed sedimentological data observed by the rover Curiosity," said co-author Alberto G. Fairén, a visiting astrobiologist in the College of Arts and Sciences. "Deposits left behind by megafloods had not been previously identified with orbiter data."

As is the case on Earth, geological features including the work of water and wind have been frozen in time on Mars for about 4 billion years. These features convey processes that shaped the surface of both planets in the past.

This case includes the occurrence of giant wave-shaped features in sedimentary layers of Gale crater, often called "megaripples" or antidunes that are about 30-feet high and spaced about 450 feet apart, according to lead author Ezat Heydari, a professor of physics at Jackson State University.

The antidunes are indicative of flowing megafloods at the bottom of Mars' Gale Crater about 4 billion years ago, which are identical to the features formed by melting ice on Earth about 2 million years ago, Heydari said.

The most likely cause of the Mars flooding was the melting of ice from heat generated by a large impact, which released carbon dioxide and methane from the planet's frozen reservoirs. The water vapor and release of gases combined to produce a short period of warm and wet conditions on the red planet.

Condensation formed water vapor clouds, which in turn created torrential rain, possibly planetwide. That water entered Gale Crater, then combined with water coming down from Mount Sharp (in Gale Crater) to produce gigantic flash floods that deposited the gravel ridges in the Hummocky Plains Unit and the ridge-and-trough band formations in the Striated Unit.

The Curiosity rover science team has already established that Gale Crater once had persistent lakes and streams in the ancient past. These long-lived bodies of water are good indicators that the crater, as well as Mount Sharp within it, were capable of supporting microbial life.

"Early Mars was an extremely active planet from a geological point of view," Fairén said. "The planet had the conditions needed to support the presence of liquid water on the surface -- and on Earth, where there's water, there's life.

"So early Mars was a habitable planet," he said. "Was it inhabited? That's a question that the next rover Perseverance ... will help to answer."

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Age is no barrier to successful weight loss

 Obese patients over the age of 60 can lose an equivalent amount of weight as younger people using only lifestyle changes, according to a new study from the University of Warwick and University Hospitals Coventry and Warwickshire (UHCW) NHS Trust that demonstrates that age is no barrier to losing weight.

The researchers hope that their findings will help to correct prevailing societal misconceptions about the effectiveness of weight loss programmes in older people, as well dispel myths about the potential benefits of older people trying to reduce their weight.

The findings are based on analysis of patient records from a hospital-based obesity service and are reported in the journal Clinical Endocrinology.

This retrospective study was conducted at the Warwickshire Institute for the Study of Diabetes, Endocrinology and Metabolism (WISDEM) at UHCW. The researchers randomly selected 242 patients who attended the WISDEM-based obesity service between 2005 and 2016, and compared two groups (those aged under 60 years and those aged between 60 and 78 years) for the weight loss that they achieved during their time within the service.

All patients had their body weight measured both before and after lifestyle interventions administered and coordinated within the WISDEM-based obesity service, and the percentage reduction in body weight calculated across both groups. When compared, the two groups were equivalent statistically, with those aged 60 years and over on average reducing their body weight by 7.3% compared with a body weight reduction of 6.9% in those aged under 60 years. Both groups spent a similar amount of time within the obesity service, on average 33.6 months for those 60 years and over, and 41.5 months for those younger than 60 years.

The hospital-based programme used only lifestyle-based changes tailored to each individual patient, focusing on dietary changes, psychological support and encouragement of physical activity. Most of the patients referred to the obesity service were morbidly obese with BMIs typically over 40Kgm-2.

There are more than fifty co-morbidities of obesity that can be lessened as we lose weight, including diabetes, psychiatric conditions such as depression and anxiety, osteoarthritis and other mechanical problems. Obesity is also linked to increased mortality and poor wellbeing.

Lead author Dr Thomas Barber of Warwick Medical School at the University of Warwick said: "Weight loss is important at any age, but as we get older we're more likely to develop the weight-related co-morbidities of obesity. Many of these are similar to the effects of aging, so you could argue that the relevance of weight loss becomes heightened as we get older, and this is something that we should embrace.

"There are a number of reasons why people may discount weight loss in older people. These include an 'ageist' perspective that weight-loss is not relevant to older people and misconceptions of reduced ability of older people to lose weight through dietary modification and increased exercise. Older people may feel that hospital-based obesity services are not for them. Service providers and policymakers should appreciate the importance of weight loss in older people with obesity, for the maintenance of health and wellbeing, and the facilitation of healthy ageing. Furthermore, age per se should not contribute towards clinical decisions regarding the implementation of lifestyle management of older people.

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Building blocks of life can form long before stars

 An international team of scientists have shown that glycine, the simplest amino acid and an important building block of life, can form under the harsh conditions that govern chemistry in space.

The results, published in Nature Astronomy, suggest that glycine, and very likely other amino acids, form in dense interstellar clouds well before they transform into new stars and planets.

Comets are the most pristine material in our Solar System and reflect the molecular composition present at the time our Sun and planets were just about to form. The detection of glycine in the coma of comet 67P/Churyumov-Gerasimenko and in samples returned to Earth from the Stardust mission suggests that amino acids, such as glycine, form long before stars. However until recently, it was thought that glycine formation required energy, setting clear constraints to the environment in which it can be formed.

In the new study the international team of astrophysicists and astrochemical modelers, mostly based at the Laboratory for Astrophysics at Leiden Observatory, the Netherlands, have shown that it is possible for glycine to form on the surface of icy dust grains, in the absence of energy, through 'dark chemistry'. The findings contradict previous studies that have suggested UV radiation was required to produce this molecule.

Dr Sergio Ioppolo, from Queen Mary University of London and lead author of the article, said: "Dark chemistry refers to chemistry without the need of energetic radiation. In the laboratory we were able to simulate the conditions in dark interstellar clouds where cold dust particles are covered by thin layers of ice and subsequently processed by impacting atoms causing precursor species to fragment and reactive intermediates to recombine."

The scientists first showed methylamine, the precursor species of glycine that was detected in the coma of the comet 67P, could form. Then, using a unique ultra-high vacuum setup, equipped with a series of atomic beam lines and accurate diagnostic tools, they were able to confirm glycine could also be formed, and that the presence of water ice was essential in this process.

Further investigation using astrochemical models confirmed the experimental results and allowed the researchers to extrapolate data obtained on a typical laboratory timescale of just one day to interstellar conditions, bridging millions of years. "From this we find that low but substantial amounts of glycine can be formed in space with time," said Professor Herma Cuppen from Radboud University, Nijmegen, who was responsible for some of the modelling studies within the paper.

"The important conclusion from this work is that molecules that are considered building blocks of life already form at a stage that is well before the start of star and planet formation," said Harold Linnartz, Director of the Laboratory for Astrophysics at Leiden Observatory. "Such an early formation of glycine in the evolution of star-forming regions implies that this amino acid can be formed more ubiquitously in space and is preserved in the bulk of ice before inclusion in comets and planetesimals that make up the material from which ultimately planets are made."

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Blue Ring Nebula: 16-year-old cosmic mystery solved, revealing stellar missing link

 In 2004, scientists with NASA's space-based Galaxy Evolution Explorer (GALEX) spotted an object unlike any they'd seen before in our Milky Way galaxy: a large, faint blob of gas with a star at its center. Though it doesn't actually emit light visible to the human eye, GALEX captured the blob in ultraviolet (UV) light and thus appeared blue in the images; subsequent observations also revealed a thick ring structure within it. So the team nicknamed it the Blue Ring Nebula. Over the next 16 years, they studied it with multiple Earth- and space-based telescopes, including W. M. Keck Observatory on Maunakea in Hawaii, but the more they learned, the more mysterious it seemed.

A new study published online on Nov. 18 in the journal Nature may have cracked the case. By applying cutting-edge theoretical models to the slew of data that has been collected on this object, the authors posit the nebula -- a cloud of gas in space -- is likely composed of debris from two stars that collided and merged into a single star.

While merged star systems are thought to be fairly common, they are nearly impossible to study immediately after they form because they're obscured by debris kicked up by the collision. Once the debris has cleared -- at least hundreds of thousands of years later -- they're challenging to identify because they resemble non-merged stars. The Blue Ring Nebula appears to be the missing link: astronomers are seeing the star system only a few thousand years after the merger, when evidence of the union is still plentiful. It appears to be the first known example of a merged star system at this stage.

Operated between 2003 and 2013 and managed by NASA's Jet Propulsion Laboratory in Southern California, GALEX was designed to help study the history of star formation by observing young star populations in UV light. Most objects seen by GALEX radiated both near-UV (represented as yellow in GALEX images) and far-UV (represented as blue), but the Blue Ring Nebula stood out because it emitted only far-UV light.

The object's size was similar to that of a supernova remnant, which forms when a massive star runs out of fuel and explodes, or a planetary nebula, the puffed-up remains of a star the size of our Sun. But the Blue Ring Nebula had a living star at its center. Furthermore, supernova remnants and planetary nebulas radiate in multiple light wavelengths outside the UV range, whereas the Blue Ring Nebula did not.

PHANTOM PLANET

In 2006, the GALEX team looked at the nebula with the 5.1-meter Hale telescope at the Palomar Observatory in San Diego County, California, and then with the even more powerful 10-meter Keck Observatory telescopes. They found evidence of a shockwave in the nebula using Keck Observatory's Low Resolution Imaging Spectrometer (LRIS), suggesting the gas composing the Blue Ring Nebula had indeed been expelled by some kind of violent event around the central star.

"Keck's LRIS spectra of the shock front was invaluable for nailing down how the Blue Ring Nebula came to be," said Keri Hoadley, an astrophysicist at Caltech and lead author of the study. "Its velocity was moving too fast for a typical planetary nebula yet too slow to be a supernova. This unusual, in-between speed gave us a strong clue that something else must have happened to create the nebula."

Data from Keck Observatory's High-Resolution Echelle Spectrometer (HIRES) also suggested the star was pulling a large amount of material onto its surface. But where was the material coming from?

"The HIRES observations at Keck gave us the first evidence that the system was accreting material," said co-author Mark Seibert, an astrophysicist with the Carnegie Institution for Science and a member of the GALEX team at Caltech, which manages JPL. "For quite a long time we thought that maybe there was a planet several times the mass of Jupiter being torn apart by the star, and that was throwing all that gas out of the system. Though the HIRES data appeared to support this theory, it also told us to be wary of that interpretation, suggesting the accretion may have something to do with motions in the atmosphere of the central star."

To gather more data, in 2012, the GALEX team used NASA's Wide-field Infrared Survey Explorer (WISE), a space telescope that studied the sky in infrared light, and identified a disk of dust orbiting closely around the star. Archival data from three other infrared observatories also spotted the disk. The finding didn't rule out the possibility that a planet was also orbiting the star, but eventually the team would show that the disk and the material expelled into space came from something larger than even a giant planet. Then in 2017, the Hobby-Eberly Telescope in Texas confirmed there was no compact object orbiting the star.

More than a decade after discovering the Blue Ring Nebula, the team had gathered data on the system from four space telescopes, four ground-based telescopes, historical observations of the star going back to 1895 (in order to look for changes in its brightness over time), and the help of citizen scientists through the American Association of Variable Star Observers (AAVSO). But an explanation for what had created the nebula still eluded them.

STELLAR SLEUTHING

When Hoadley began working with the GALEX science team in 2017, "the group had kind of hit a wall" with the Blue Ring Nebula, she said. But Hoadley was fascinated by the thus-far unexplainable object and its bizarre features, so she accepted the challenge of trying to solve the mystery. It seemed likely that the solution would not come from more observations of the system, but from cutting-edge theories that could make sense of the existing data. So Chris Martin, principal investigator for GALEX at Caltech, reached out to Brian Metzger of Columbia University for help.

As a theoretical astrophysicist, Metzger makes mathematical and computational models of cosmic phenomena, which can be used to predict how those phenomena will look and behave. He specializes in cosmic mergers -- collisions between a variety of objects, whether they be planets and stars or two black holes.

"It wasn't just that Brian could explain the data we were seeing; he was essentially predicting what we had observed before he saw it," said Hoadley. "He'd say, 'If this is a stellar merger, then you should see X,' and it was like, 'Yes! We see that!'"

The team concluded the nebula was the product of a relatively fresh stellar merger that likely occurred between a star similar to our Sun and another only about one tenth that size (or about 100 times the mass of Jupiter). Nearing the end of its life, the Sun-like star began to swell, creeping closer to its companion. Eventually, the smaller star fell into a downward spiral toward its larger companion. Along the way, the larger star tore the smaller star apart, wrapping itself in a ring of debris before swallowing the smaller star entirely.

This was the violent event that led to the formation of the Blue Ring Nebula. The merger launched a cloud of hot debris into space that was sliced in two by the gas disk. This created two cone-shaped debris clouds, their bases moving away from the star in opposite directions and getting wider as they travel outward. The base of one cone is coming almost directly toward Earth and the other almost directly away. They are too faint to see alone, but the area where the cones overlap (as seen from Earth) forms the central blue ring GALEX observed.

Millennia passed, and the expanding debris cloud cooled and formed molecules and dust, including hydrogen molecules that collided with the interstellar medium, the sparse collection of atoms and energetic particles that fill the space between stars. The collisions excited the hydrogen molecules, causing them to radiate in a specific wavelength of far-UV light. Over time, the glow became just bright enough for GALEX to see.

Stellar mergers may occur as often as once every 10 years in our Milky Way galaxy, meaning it's possible that a sizeable population of the stars we see in the sky were once two.

"We see plenty of two-star systems that might merge someday, and we think we've identified stars that merged maybe millions of years ago. But we have almost no data on what happens in between," said Metzger. "We think there are probably plenty of young remnants of stellar mergers in our galaxy, and the Blue Ring Nebula might show us what they look like so we can identify more of them."

Though this is likely the conclusion of a 16-year-old mystery, it may also be the beginning of a new chapter in the study of stellar mergers.

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Newborn jets in distant galaxies

 Astronomers using data from the ongoing VLA Sky Survey (VLASS) have found a number of distant galaxies with supermassive black holes at their cores that have launched powerful, radio-emitting jets of material within the past two decades or so. The scientists compared data from VLASS with data from an earlier survey that also used the National Science Foundation's Karl G. Jansky Very Large Array (VLA) to reach their conclusion.

"We found galaxies that showed no evidence of jets before but now show clear indications of having young, compact jets," said Dr. Kristina Nyland, who is an NRC postdoctoral fellow in residence at the Naval Research Laboratory.

"Jets like these can strongly affect the growth and evolution of their galaxies, but we still don't understand all of the details. Catching newborn jets with surveys like VLASS provides a measure of the role of powerful radio jets in shaping the lives of the galaxies over billions of years," Nyland said.

VLASS is a project that will survey the sky visible from the VLA -- about 80 percent of the entire sky -- three times over seven years. The observations began in 2017 and the first of the three scans now is complete. Nyland and her colleagues compared data from this scan with data from the FIRST survey that used the VLA to observe a smaller portion of the sky between 1993 and 2011.

They found about 2,000 objects that appear in the VLASS images, but were not detected in the earlier FIRST survey. From these, they selected 26 objects that previously were categorized as galaxies with active nuclei -- powered by supermassive black holes -- by optical and infrared observations. The FIRST observations of the 26 objects had been made between 1994 and 2001. The VLASS observations were made in 2019. The intervals between observations of the objects thus ranged from 18 to 25 years.

They chose 14 of these galaxies for more detailed observations with the VLA. These observations provided higher-resolution images and also were done at multiple radio frequencies to get a more complete understanding of the objects' characteristics.

"The data from these detailed observations tell us that the most likely cause of the difference in radio brightness between the FIRST and the VLASS observations is that the 'engines' at the cores of these galaxies have launched new jets since the FIRST observations were made," explained Dillon Dong, from Caltech.

The black holes at the cores of galaxies are known to interact with the galaxies themselves, and the two evolve together. The jets launched from the regions near the black holes can affect the amount of star formation within the galaxy.

"Radio jets provide natural laboratories for learning about the extreme physics of supermassive black holes, whose formation and growth are believed to be intrinsically linked to that of the galaxy centers in which they reside," said Pallavi Patil, of the University of Virginia.

"Jets as young as the ones discovered in our study can provide us with a rare opportunity to gain new insights on how these interactions between the jets and their surroundings work," Nyland said.

"VLASS has proven to be a key tool for discovering such jets, and we eagerly await the results of its next two observing epochs," said Mark Lacy, of the National Radio Astronomy Observatory.

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Parental restrictions on tech use have little lasting effect into adulthood

 "Put your phone away!" "No more video games!" "Ten more minutes of YouTube and you're done!"

Kids growing up in the mobile internet era have heard them all, often uttered by well-meaning parents fearing long-term problems from overuse.

But new University of Colorado Boulder research suggests such restrictions have little effect on technology use later in life, and that fears of widespread and long-lasting "tech addiction" may be overblown.

"Are lots of people getting addicted to tech as teenagers and staying addicted as young adults? The answer from our research is 'no'," said lead author Stefanie Mollborn, a professor of sociology at the Institute of Behavioral Science. "We found that there is only a weak relationship between early technology use and later technology use, and what we do as parents matters less than most of us believe it will."

The study, which analyzes a survey of nearly 1,200 young adults plus extensive interviews with another 56, is the first to use such data to examine how digital technology use evolves from childhood to adulthood.

The data were gathered prior to the pandemic, which has resulted in dramatic increases in the use of technology as millions of students have been forced to attend school and socialize online. But the authors say the findings should come as some comfort to parents worried about all that extra screen time.

"This research addresses the moral panic about technology that we so often see," said Joshua Goode, a doctoral student in sociology and co-author of the paper. "Many of those fears were anecdotal, but now that we have some data, they aren't bearing out."

Published in Advances in Life Course Research, the paper is part of a 4-year National Science Foundation-funded project aimed at exploring how the mobile internet age truly is shaping America's youth.

Since 1997, time spent with digital technology has risen 32% among 2- to 5-year-olds and 23% among 6- to 11-year-olds, the team's previous papers found. Even before the pandemic, adolescents spent 33 hours per week using digital technology outside of school.

For the latest study, the research team shed light on young adults ages 18 to 30, interviewing dozens of people about their current technology use, their tech use as teens and how their parents or guardians restricted or encouraged it. The researchers also analyzed survey data from a nationally representative sample of nearly 1,200 participants, following the same people from adolescence to young adulthood.

Surprisingly, parenting practices like setting time limits or prohibiting kids from watching shows during mealtimes had no effect on how much the study subjects used technology as young adults, researchers found.

Those study subjects who grew up with fewer devices in the home or spent less time using technology as kids tended to spend slightly less time with tech in young adulthood -- but statistically, the relationship was weak.

What does shape how much time young adults spend on technology? Life in young adulthood, the research suggests.

Young adults who hang out with a lot of people who are parents spend more time with tech (perhaps as a means of sharing parenting advice). Those whose friends are single tend toward higher use than the married crowd. College students, meantime, tend to believe they spend more time with technology than they ever have before or ever plan to again, the study found.

"They feel like they are using tech a lot because they have to, they have it under control and they see a future when they can use less of it," said Mollborn.

From the dawn of comic books and silent movies to the birth of radio and TV, technological innovation has bred moral panic among older generations, the authors note.

"We see that everyone is drawn to it, we get scared and we assume it is going to ruin today's youth," said Mollborn.

In some cases, excess can have downsides. For instance, the researchers found that adolescents who play a lot of video games tend to get less physical activity.

But digital technology use does not appear to crowd out sleep among teens, as some had feared, and use of social media or online videos doesn't squeeze out exercise.

In many ways, Goode notes, teens today are just swapping one form of tech for another, streaming YouTube instead watching TV, or texting instead of talking on the phone.

That is not to say that no one ever gets addicted, or that parents should never instill limits or talk to their kids about its pros and cons, Mollborn stresses.

"What these data suggest is that the majority of American teens are not becoming irrevocably addicted to technology. It is a message of hope."

She recently launched a new study, interviewing teens and parents in the age of COVID-19. Interestingly, she said, parents seem less worried about their kids' tech use during the pandemic than they were in the past.

Read more at Science Daily

Henderson island fossils reveal new Polynesian sandpiper species

 Fossil bones collected in the early 1990s on Henderson Island, part of the Pitcairn Group, have revealed a new species of Polynesian sandpiper.

The Henderson Sandpiper, a small wading bird that has been extinct for centuries, is described in an article in the Zoological Journal of the Linnean Society published last week.

The newly-described bird is formally named Prosobonia sauli after Cook Islands-based ornithologist and conservationist Edward K Saul.

A team of researchers from New Zealand, Australia, Denmark, Switzerland, the Netherlands and China, led by Canterbury Museum Research Curator Natural History Dr Vanesa De Pietri, described the Henderson Sandpiper from 61 fossilised bones cared for by the Natural History Museum at Tring in England.

Canterbury Museum Visiting Researcher Dr Graham Wragg collected the bones from caves and overhangs on Henderson Island in 1991 and 1992 during the Sir Peter Scott Commemorative Expedition to the Pitcairn Islands.

Prosobonia sauli is the fifth known species of Polynesian sandpiper. All but one of the species, the endangered Tuamotu Sandpiper (Prosobonia parvirostris), are extinct.

"We think Prosobonia sauli probably went extinct soon after humans arrived on Henderson Island, which archaeologists estimate happened no earlier than the eleventh century," says Dr De Pietri.

"It's possible these humans brought with them the Polynesian rat, which Polynesian sandpiper populations are very vulnerable to."

DNA of the living Tuamotu Sandpiper and the extinct Tahiti Sandpiper (Prosobonia leucoptera), which is known only from a skin in the Naturalis Biodiversity Center in the Netherlands, was used to determine how Polynesian sandpipers are related to other wading birds.

"We found that Polynesian sandpipers are early-diverging members of a group that includes calidrine sandpipers and turnstones. They are unlike other sandpipers in that they are restricted to islands of the Pacific and do not migrate," says Dr De Pietri.

Comparisons with the other two extinct Polynesian sandpiper species, the Kiritimati Sandpiper (Prosobonia cancellata) and the Mo'orea Sandpiper (Prosobonia ellisi), are complicated. These birds are known only from illustrations primarily by William Wade Ellis, an artist and Surgeon's Mate on Captain James Cook's third expedition, who probably saw the birds alive in the 1770s.

Compared to the Tuamotu Sandpiper, its geographically closest cousin, the Henderson Sandpiper had longer legs and a wider, straighter bill, indicating how it foraged for food. It probably adapted to the habitats available on Henderson Island, which are different to those on other islands where Polynesian sandpipers were found.

Henderson Island is the largest island in the Pitcairn Group, in the middle of the South Pacific Ocean. It has been uninhabited since around the fifteenth century and was designated a World Heritage Site by the United Nations in 1988.

Dr Paul Scofield, Canterbury Museum Senior Curator Natural History and one of the study's co-authors, says Henderson Island is home to a number of unique species, a handful of which are landbirds like the Henderson Sandpiper.

"The island is really quite remarkable because every landbird species that lives there, or that we know used to live there, is not found anywhere else," he says.

Dr De Pietri says the study shows the need to protect the one remaining Polynesian sandpiper species, the Tuamotu Sandpiper.

"We know that just a few centuries ago there were at least five Polynesian sandpiper species scattered around the Pacific. Now there's only one, and its numbers are declining, so we need to ensure we look after the remaining populations."

Read more at Science Daily

Abundance of prey species is key to bird diversity in cities

 Urbanisation represents a drastic change to natural habitats and poses multiple challenges to many wildlife species, thereby affecting the occurrence and the abundance of many bird species. A team of scientists from the Leibniz Institute for Zoo and Wildlife Research (Leibniz-IZW) and the Technische Universität Berlin (TUB) collaborated to analyse breeding bird data from the Senate of Berlin gathered by citizen scientists. They found that the abundance of invertebrates such as insects or spiders as prey is a key factor affecting bird diversity in the city. The more prey is available, the more diverse the urban bird communities are. This demonstrates the importance of species interactions for explaining urban biodiversity in addition to impacts of anthropogenic disturbance and habitat structure. The results are published in the scientific journal Diversity and Distributions.

Species interactions profoundly shape the composition of wildlife communities, determining which species and how many individuals are found within given habitats. For example, the presence of strong competitors may result in a diminished abundance or exclusion of particular species. Similarly, prey abundance and distribution affect the numbers of predators in a community. "Although the importance of species interactions for generating biodiversity is widely recognized, studies of urban biodiversity usually focus on the impacts of anthropogenic disturbance and habitat structure, neglecting species interactions," says Stephanie Kramer-Schadt, head of the Leibniz-IZW Department of Ecological Dynamics and Professor at TUB.

To assess to what extent species interactions affect avian diversity in cities, the team led by Aimara Planillo from Leibniz-IZW analysed breeding bird monitoring data and related them to invertebrate data. Bird data were collected by citizen scientists and provided by the Senate of Berlin, and invertebrate data were collected within a collaborative project of Berlin research institutions (BBIB-BIBS) funded by the German Ministry of Education and Research (BMBF). They investigated the impact of both food-related (prey availability) and non-food related (e.g. competition) species interactions on the responses of bird species to a gradient of increasing urbanisation, using data from 66 breeding bird species in the city of Berlin.

"By applying sophisticated modelling techniques to the biodiversity data, we demonstrated that prey invertebrate abundance is one of the most important factors affecting the urban bird biodiversity," says Planillo. Senior author Radchuk adds: "Importantly, the impact of prey abundance depends on the level of urbanisation. Prey abundance had a positive effect on bird diversity under low to medium urbanisation levels. For the highly urbanised areas, prey abundance does not affect bird community, as the bird species inhabiting such areas are those adapted to persist in urban environments and often benefit from human resources."

Through these analyses the scientists were able to distinguish three different groups of bird species in Berlin, which differ in how they respond to environmental variables and to prey abundance. "We found urban species, woodland species and nature-area species in Berlin's bird community," Radchuk explains. "Urban species are akin to urban exploiters as they persisted at high abundance at high levels of anthropogenic disturbance. Woodland species are akin to urban adapters, they responded strongly to the urbanisation gradient and were favoured by high tree cover and invertebrate abundance. Finally, nature-area species were strongly negatively affected by urbanisation and positively by tree cover and open green area. They were also the least abundant of the three groups."

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Extremely rare parasitic crustacean discovered in museum shark collection

 Scientists have discovered an extremely rare species of cymothoid from the mouth of a museum specimen of a deep-sea shark caught from the East China Sea, suggesting its wide distribution around the globe.

Cymothoids are a family of isopods (a type of crustacean) that are ectoparasites of fish. Some species in this family are also known as tongue-biter or tongue-eating louse (e.g., Cymothoa exigua).

Assistant Professor Ryota Kawanishi and Dr. Shinpei Ohashi from Hokkaido University have reported the discovery of an extremely rare species of cymothoid, Elthusa splendida, from the East China Sea. Their paper, published in the journal Species Diversity, expands the range of this species to almost the opposite sides of the Earth.

Cymothoids are a diverse family of more than 300 species of parasites, and parasitize a wide variety of fish, from freshwater to the deep sea. A recent study into the genetics of the family has shown that it is highly likely that they evolved in the deep sea and diversified. A number of deep sea cymothoids, however, are poorly studied, primarily due to the difficulty of deep sea sampling.

Elthusa splendida is the least studied of all deep sea cymothoids. Only five specimens have ever been cataloged and described, in 1981. Those specimens were recovered from a Cuban dogfish, a deep-sea shark, which was captured off southern Brazil in the western South Atlantic. No additional specimens have been reported since then.

In the current study, the scientists discovered the specimen of Elthusa splendida while processing fish specimens at the Fisheries Science Center, Hokkaido University Museum (HUMZ), Hakodate. The specimen was found in a Japanese spurdog, also a deep-sea shark, that had been collected from the East China Sea in June 2003 and preserved in formalin. The scientists confirmed the identification of the specimen by comparing the morphological features of the specimen with the original description of the species. The unique feature that defines Elthusa splendida is the presence of four pits on the first pereonite (first segment behind the head); this feature was examined using a computerized 3D measurement system. DNA sequencing was not used for identification as the sequence of the original specimen is unknown.

This discovery is important as it shows the distribution of Elthusa splendida extends from two locations that are almost antipodal to each other -- almost as far as it is physically possible to be on the planet. The scientists suggest that other species of deep sea cartilaginous fish in the genus Squalus (to which both the Cuban dogfish and the Japanese spurdog belong) can potentially serve as hosts for this parasite. They have also confirmed that Elthusa splendida is rare among other Elthusa species in parasitizing the mouth of the host, rather than the gills; furthermore, even among those cymothoids that parasitize the mouth, Elthusa splendida is one of the rare species that attach to the palate.

Read more at Science Daily

Masks don't impair lung function during physical activity, study finds

 Wearing a facemask helps limit the spread of COVID-19 by reducing respiratory droplets and aerosols spewed into the air when people breathe, talk, laugh, sneeze or cough. But the physical barrier created by masks has prompted concerns that they might impair the cardiopulmonary system by making it harder to breathe, by altering the flow of inhaled oxygen and exhaled carbon dioxide and by increasing dyspnea -- a medical term that describe shortness of breath or difficulty breathing, especially during physical activity.

In a new study, published November 16, 2020 in the Annals of the American Thoracic Society, a team of American and Canadian researchers concluded that while sensations of dyspnea might increase, there is little empirical evidence that wearing a facemask significantly diminishes lung function, even when worn during heavy exercise.

"There might be a perceived greater effort with activity, but the effects of wearing a mask on the work of breathing, on gases like oxygen and CO2 in blood or other physiological parameters are small, often too small to be detected," said the study's first author Susan Hopkins, MD, PhD, professor of medicine and radiology at University of California San Diego School of Medicine.

"There's also no evidence to support any differences by sex or age in physiological responses to exercise while wearing a facemask," added Hopkins, who specializes in exercise physiology and the study of lungs under stress.

The single exception, the authors note, may be persons with severe cardiopulmonary disease in which any added resistance to breathing or minor changes in blood gases could prompt dyspnea great enough to affect exercise capacity.

"In such cases, these individuals might feel too uncomfortable to exercise, and that should be discussed with their doctor," Hopkins said. "However, the fact that these individuals are at great risk should they contract COVID-19 must also be considered"

The researchers came to their conclusions following a review of all known scientific literature published that examined the effects of various facemasks and respiratory loading devices on physiological and perceptual responses to physical activity. These studies assessed multiple factors, such as work of breathing (the quantified energy expended to inhale and exhale), arterial blood gases, effects on muscle blood flow and fatigue, cardiac function and flow of blood to the brain.

For healthy persons, the effects of wearing a mask on these physiological markers were minimal, no matter what type of mask was worn or the degree of exercise. The authors also said age played no significant influencing role among adults. Gender differences were deemed inconsequential.

"Wearing a facemask can be uncomfortable," said Hopkins. "There can be tiny increases in breathing resistance. You may re-inhale warmer, slightly enriched CO2 air. And if you're exercising, the mask can cause your face to become hot and sweaty.

"But these are sensory perceptions. They do not impact cardiopulmonary function in healthy people. So while dyspnea might be increased with a mask, you have to weigh that against the reduced risk of contracting COVID-19, knowing that the physiology is essentially unchanged."

Read more at Science Daily

Ancient zircon minerals from Mars reveal the elusive internal structure of the red planet

 The uranium-bearing mineral zircon is an abundant constituent of Earth's continental crust, providing information about the age and origin of the continents and large geological features such as mountain chains and giant volcanoes. But unlike Earth, Mars's crust is not evolved and is compositionally similar to the crust found under the Earth's oceans, where zircon is rare. Therefore, zircon is not expected to be a common mineral on Mars.

"We were quite surprised and excited when we found so many zircons in this martian meteorite. Zircon are incredible durable crystals that can be dated and preserve information that tell us about their origins. Having access to so many zircons is like opening a time window into the geologic history of planet," describes Professor Martin Bizzarro from the GLOBE Institute, who led the study.

The team investigated the ancient Martian meteorite NWA 7533, dubbed "Black Beauty," which was discovered in the desert of Morocco in 2011. After crushing 15 grams of this rock, they extracted about 60 zircons. By age-dating the zircons, they found that the majority of crystals date back to about 4.5 billion years ago, namely the very beginning of the planet's life. But they also made an unexpected discovery: some of the zircons defined much younger ages, ranging from about 1500 million years down to 300 million years.

"These young ages were a great surprise," says Bizzarro. "The Black Beauty meteorite is believed to come from the southern hemisphere of Mars, which does not have any young volcanic terrains. The only possible source for these young zircons is the Tharsis volcanic province located in the northern hemisphere of the planet, which contains large volcanoes that were recently active," Martin Bizzarro adds.

The Tharsis bulge on Mars is an enormous volcanic province that hosts the largest volcanoes in the Solar System, which are up to 21 km high. Scientists believe that this volcanic province is the expression of very deep magmatism that erupts on the planets surface. The analogy on Earth is the Hawaiian volcanic chain of islands, which is also believed to reflect deep-seated volcanic activity. But because of plate tectonics, the Pacific Plate is constantly moving such that, instead of accumulating at one single location, a chain of progressively younger volcanic islands has formed. Since Mars does not have plate tectonics, the volcanoes pile up at one single location and as a result grow to gigantic sizes.

If Bizzarro's team is correct, it means that the young zircons may contain information about the deep, inaccessible interior of Mars. This is the first time that scientists have direct access to the deep interior of the red planet via these samples, which may allow them to uncover the internal structure and composition of Mars.

"Having samples of the deep interior of Mars is key. This means that we can now use these zircons to probe the origin of the volatile elements on Mars, including its water, and see how it compares with Earth and other planets in the Solar System," explains Mafalda Costa, first other of the new study.

But to understand the nature of the deep martian interior, the researchers turned to the analysis of the isotopic composition of the element hafnium in the same zircons.

"Because hafnium is a major elemental constituent of zircon, it retains a memory of where the zircon formed," says Martin Bizzarro. "We found that the hafnium isotope composition of the young zircons is unlike any of the known Martian meteorites, which indicates that the young zircons come from a primitive reservoir that we did not know existed in the interior of Mars," he adds.

The hafnium isotope composition of the young zircons is similar to the most primitive objects in the Solar System, that is, chondrite meteorites. These chondrite meteorites are samples of asteroids that have never been modified since their formation. This implies that the deep interior of Mars has essentially not been modified since the formation of the planet. The existence of such a primitive reservoir is expected for a planet lacking plate tectonics. In contrast to Earth, where material formed at surface is continuously recycled into the interior by plate tectonics, the deep interior of Mars has remained unchanged since the birth of the planet and, as such, preservers its initial composition.

Finally, the discovery that zircon may be abundant on the Martian surface may guide the future robotic exploration of the planet, especially in the framework of returning samples to Earth.

Read more at Science Daily

The long road to dementia

 Alzheimer's disease develops over decades. It begins with a fatal chain reaction in which masses of misfolded beta-amyloid proteins are produced that in the end literally flood the brain. Researchers including Mathias Jucker from the Hertie Institute for Clinical Brain Research (HIH) in Tübingen and the German Center for Neurodegenerative Diseases (DZNE) show in the journal Nature Neuroscience that this chain reaction starts much earlier in mice than commonly assumed. This means that in addition to the well-known early phase of the disease with protein deposits but without symptoms of dementia, there is an even earlier phase in which the chain reaction is triggered by invisible tiny seeds of aggregation. If this is confirmed to occur also in humans, a treatment addressing the causes of disease would have to prevent this process. The scientists have already identified an antibody that might accomplish this.

To this end, they searched among the already known antibodies directed against misfolded beta-amyloid proteins for antibodies that can recognize and possibly also eliminate these early seeds of aggregation that currently escape biochemical detection. Of the six antibodies investigated, only aducanumab had an effect: Transgenic mice that were treated for only 5 days before the first protein deposits manifested, later on in life showed only half of the usual amount of deposits in their brains. "This acute antibody treatment obviously removes seeds of aggregation, and the generation of new seeds takes quite some time, so that much less deposits are formed in the weeks and months after the treatment." Mathias Jucker commented on the findings. "Indeed, the mice had only half the brain damage six months after this acute treatment."

Although research on Alzheimer's has been dealing with seeds of aggregation for quite some time, nobody really knows what they look like. They are currently only defined by their role as triggers for this fatal chain reaction. In this respect, they are similar to so-called prions that cause BSE in cattle, scrapie in sheep and Creutzfeldt-Jakob disease in humans. Pathogenic prions force their correctly folded peers into their abnormal shape. Jucker and coworkers therefore used the antibody aducanumab to learn more about the structure of the seeds of aggregation. They were able to show that aducanumab recognizes protein aggregates, but not individual beta-amyloid chains. The scientists now hope to use the antibody as a fishhook to isolate and better describe these seeds of aggregation.

"Our results suggest that we need to focus more on this very early phase of Alzheimer's and look for biomarkers for it. We also need more antibodies that recognize different types of the seeds of aggregation and help us to understand how they trigger the chain reaction and how they can be used for therapy," Jucker said.

Read more at Science Daily

Healthy sleep habits help lower risk of heart failure

 

Woman waking up in the morning

Adults with the healthiest sleep patterns had a 42% lower risk of heart failure regardless of other risk factors compared to adults with unhealthy sleep patterns, according to new research published today in the American Heart Association's flagship journal Circulation. Healthy sleep patterns are rising in the morning, sleeping 7-8 hours a day and having no frequent insomnia, snoring or excessive daytime sleepiness.

Heart failure affects more than 26 million people, and emerging evidence indicates sleep problems may play a role in the development of heart failure.

This observational study examined the relationship between healthy sleep patterns and heart failure and included data on 408,802 UK Biobank participants, ages 37 to 73 at the time of recruitment (2006-2010). Incidence of heart failure was collected until April 1, 2019. Researchers recorded 5,221 cases of heart failure during a median follow-up of 10 years.

Researchers analyzed sleep quality as well as overall sleep patterns. The measures of sleep quality included sleep duration, insomnia and snoring and other sleep-related features, such as whether the participant was an early bird or night owl and if they had any daytime sleepiness (likely to unintentionally doze off or fall asleep during the daytime).

"The healthy sleep score we created was based on the scoring of these five sleep behaviors," said Lu Qi, M.D., Ph.D., corresponding author and professor of epidemiology and director of the Obesity Research Center at Tulane University in New Orleans. "Our findings highlight the importance of improving overall sleep patterns to help prevent heart failure."

Sleep behaviors were collected through touchscreen questionnaires. Sleep duration was defined into three groups: short, or less than 7 hours a day; recommended, or 7 to 8 hours a day; and prolonged, or 9 hours or more a day.

After adjusting for diabetes, hypertension, medication use, genetic variations and other covariates, participants with the healthiest sleep pattern had a 42% reduction in the risk of heart failure compared to people with an unhealthy sleep pattern.

They also found the risk of heart failure was independently associated and:
 

• 8% lower in early risers;
• 12% lower in those who slept 7 to 8 hours daily;
• 17% lower in those who did not have frequent insomnia; and
• 34% lower in those reporting no daytime sleepiness.

Participant sleep behaviors were self-reported, and the information on changes in sleep behaviors during follow-up were not available. The researchers noted other unmeasured or unknown adjustments may have also influenced the findings.

Qi also noted that the study's strengths include its novelty, prospective study design and large sample size.

Read more at Science Daily

From the inside out: How the brain forms sensory memories

 

Neurons illustration

The brain encodes information collected by our senses. However, to perceive our environment and to constructively interact with it, these sensory signals need to be interpreted in the context of our previous experiences and current aims. In the latest issue of Science, a team of scientists led by Dr. Johannes Letzkus, Research Group Leader at the Max Planck Institute for Brain Research, has identified a key source of this experience-dependent top-down information.

The neocortex is the largest area of the human brain. It has expanded and differentiated enormously during mammalian evolution, and is thought to mediate many of the capacities that distinguish humans from their closest relatives. Moreover, dysfunctions of this area also play a central role in many psychiatric disorders. All higher cognitive functions of the neocortex are enabled by bringing together two distinct streams of information: a 'bottom-up' stream carrying signals from the surrounding environment, and a 'top-down' stream that transmits internally-generated information encoding our previous experiences and current aims.

"Decades of investigation have elucidated how sensory inputs from the environment are processed. However, our knowledge of internally-generated information is still in its infancy. This is one of the biggest gaps in our understanding of higher brain functions like sensory perception," says Letzkus. This motivated the team to search for the sources of these top-down signals. "Previous work by us and many other scientists had suggested that the top-most layer of neocortex is likely a key site that receives inputs carrying top-down information. Taking this as a starting point allowed us to identify a region of the thalamus -- a brain area embedded deep within the forebrain -- as a key candidate source of such internal information."

Motivated by these observations Dr. M. Belén Pardi, the first author of the study and postdoctoral researcher in the Letzkus lab, devised an innovative approach that enabled her to measure the responses of single thalamic synapses in mouse neocortex before and after a learning paradigm. "The results were very clear," Pardi remembers. "Whereas neutral stimuli without relevance were encoded by small and transient responses in this pathway, learning strongly boosted their activity and made the signals both faster and more sustained over time." This suggests that the thalamic synapses in neocortex encode the previous experience of the animal. "We were really convinced that this is the case when we compared the strength of the acquired memory with the change in thalamic activity: This revealed a strong positive correlation, indicating that inputs from the thalamus prominently encode the learned behavioral relevance of stimuli," says Letzkus.

But is this mechanism selective for these top-down memory-related signals? Sensory stimuli can be relevant because of what we have learned to associate with them, but also merely due to their physical properties. For instance, the louder sounds are the more readily they recruit attention in both humans and animals. However, this is a low-level function that has little to do with previous experience. "Intriguingly, we found very different, indeed opposite, encoding mechanisms for this bottom-up form of relevance" says Pardi.

Given their central importance, the scientists speculated that the way these signals are received in the neocortex must be tightly regulated. Pardi and co-workers addressed this in further experiments, combined with computational modeling in collaboration with the laboratory of Dr. Henning Sprekeler and his team at Technische Universität Berlin. The results indeed identified a previously unknown mechanism that can finely tune the information along this pathway, identifying a specialized type of neuron in the top-most layer of neocortex as a dynamic gatekeeper of these top-down signals.

Read more at Science Daily

Paleontologists uncover three new species of extinct walruses in Orange County, California

 Millions of years ago, in the warm Pacific Ocean off the coast of Southern California, walrus species without tusks lived abundantly.

But in a new study, Cal State Fullerton paleontologists have identified three new walrus species discovered in Orange County and one of the new species has "semi-tusks" -- or longer teeth.

The other two new species don't have tusks and all predate the evolution of the long iconic ivory tusks of the modern-day walrus, which lives in the frigid Arctic.

The researchers describe a total of 12 specimens of fossil walruses from Orange, Los Angeles and Santa Cruz counties, all estimated to be 5 to 10 million years old. The fossils represent five species, with two of the three new species represented by specimens of males, females and juveniles.

Their research, which gives insights on the dental and tusk evolution of the marine mammal, was published today in the Journal of Vertebrate Paleontology.

Geology graduate Jacob Biewer, and his research adviser James F. Parham, associate professor of geological sciences, are authors of the study, based on fossil skull specimens.

Parham and Biewer worked with Jorge Velez-Juarbe, an expert in marine mammals at the Natural History Museum of Los Angeles County, who is a co-author of the paper. Velez-Juarbe is a former postdoctoral scholar in Parham's lab and has collaborated on other CSUF fossil research projects. Parham is a research associate at the museum, which provides research opportunities for him and his students.

The researchers teamed to study and describe the anatomy of the specimens, most of which are part of the museum's collection.

"Orange County is the most important area for fossil walruses in the world," said Biewer, first author of the paper who conducted the research for his master's thesis. "This research shows how the walruses evolved with tusks."

Extinct Walrus Species Get Names

Today, there is only one walrus species and its scientific name is Odobenus.

For the new species found in Orange County, the researchers named the semi-tusked walrus, Osodobenus eodon, by combining the words Oso and Odobenus. Another is named Pontolis kohnoi in honor of Naoki Kohno, a fossil walrus researcher from Japan. Both of these fossils were discovered in the Irvine, Lake Forest and Mission Viejo areas.

Osodobenus eodon and Pontolis kohnoi are both from the same geological rock layer as the 2018 study by Parham and his students of another new genus and species of a tuskless walrus, Titanotaria orangensis, named after CSUF Titans. These fossils were found in the Oso Member of the Capistrano Formation, a geological formation near Lake Forest and Mission Viejo.

The third new walrus species, Pontolis barroni, was found in Aliso Viejo, near the 73 Toll Road. It is named after John Barron, a retired researcher from the U.S.Geological Survey and world expert on the rock layer where the specimens were found, Parham said.

Analysis of these specimens show that fossil walrus teeth are more variable and complex than previously considered. Most of the new specimens predate the evolution of tusks, Parham said.

"Osodobenus eodon is the most primitive walrus with tusk-like teeth," Parham said. "This new species demonstrates the important role of feeding ecology on the origin and early evolution of tusks."

Biewer explained that his work focused on getting a better understanding of the evolutionary history of the walrus in regards to its teeth.

"The importance of dental evolution is that it shows the variability within and across walrus species. Scientists assumed you could identify certain species just based on the teeth, but we show how even individuals of the same species could have variability in their dental setup," said Biewer, who earned a master's degree in geology in 2019.

"Additionally, everyone assumes that the tusks are the most important teeth in a walrus, but this research further emphasizes how tusks were a later addition to the history of walruses. The majority of walrus species were fish eaters and adapted to catching fish, rather than using suction feeding on mollusks like modern walruses."

Biewer, now a paleontologist in the Modesto area, also examined whether climate changes in the Pacific Ocean had an impact on ancient walruses. His work suggests that a rise in water temperature helped to boost nutrients and planktonic life, and played a role in the proliferation of walruses about 10 million years ago, which may have contributed to their diversity.

Background

For the fossil walrus research project, geology graduate Jacob Biewer spent hours in the lab measuring and describing the walrus bones.

"I sat many hours with a handy caliper taking notes on the lengths of teeth and width of skulls, among many other measurements," he said. "Describing bones is much more in depth and meticulous than it sounds. There are traits that the bones of each walrus species have -- the size, shape and number of teeth. I recorded how the bones are different from, or similar to, other extinct walrus species."

Biewer, a paleontologist who lives in Modesto, noted that despite the pandemic, he and Parham worked on the scientific paper with 300 miles of social distancing.

Completing his first journal publication, based on his master's work, and conducting the research project helped him to understand scientific methods and techniques that he now uses in his career, where he monitors construction sites for paleontological resources. He also teaches undergraduate geology courses at Cal State Stanislaus, where he earned a bachelor's degree in geology, and is considering pursuing a doctorate.

Read more at Science Daily

New tool predicts geological movement and the flow of groundwater in old coalfields

 A remote monitoring tool to help authorities manage public safety and environmental issues in recently abandoned coal mines has been developed by the University of Nottingham.

The tool uses satellite radar imagery to capture millimetre-scale measurements of changes in terrain height. Such measurements can be used to monitor and forecast groundwater levels and changes in geological conditions deep below the earth's surface in former mining areas.

With a long history of coal mining, the project was tested in the UK at a regional scale, but has global implications given the worldwide decline in the demand for coal in favour of more sustainable energy sources.

The method was implemented over the Nottinghamshire coalfields, which were abandoned as recently as 2015, when the last deep mine, Thoresby Colliery, shut its doors for good.

When deep mines are closed, the groundwater that was previously pumped to the surface to make mining safe, is allowed to rise again until it is restored to its natural level in a process called rebound.

The rebound of groundwater through former mine workings needs careful monitoring; often containing contaminants it can pollute waterways and drinking water supplies; lead to localised flooding; renew mining subsidence, land uplift and reactivate geological faults if it rises too fast. Such issues can cause costly and hazardous problems that need to be addressed prior to the land being repurposed.

The Coal Authority therefore needs detailed information on the rebound rate across the vast mine systems it manages so it knows exactly where to relax or increase pumping to control groundwater levels.

Measuring the rate and location of mine water rebound is therefore vital to effectively manage the environmental and safety risks in former coalfields, but difficult to achieve. Groundwater can flow in unanticipated directions via cavities within and between neighbouring collieries and discharge at the surface in areas not thought to be at risk.

In the past, predicting where mine water will flow was heavily-reliant on mine plans; inaccurate or incomplete documents that are sometimes more than a century old; and borehole data. Costing approximately £20,000 to £350K each, boreholes are expensive to drill and are often sparsely situated across vast coalfields, leaving measurement gaps.

More recently uplift, subsidence and other geological motion has been monitored by applying Interferometric Synthetic Aperture Radar (InSAR) to images acquired from radar satellites. However, this interferometry technique has historically worked only in urban areas (as opposed to rural ones), where the radar can pick up stable objects, such as buildings or rail tracks, on the ground to reflect back regularly to the satellite.

This study uses an advanced InSAR technique, called Intermittent Small Baseline Subset (ISBAS), developed by the University of Nottingham and its spin-out company Terra Motion Ltd. InSAR uses stacks of satellite images of the same location taken every few days or weeks which makes it possible to pick up even the slightest topographical changes over time. Uniquely, ISBAS InSAR can compute land deformation measurements over both urban and rural terrain. This is beneficial when mapping former mining areas, which are often located in rural areas. Over the Nottinghamshire coalfields, for example, the land cover is predominantly rural, with nearly 80 per cent comprising agricultural land, pastures and semi-natural areas.

Such a density of measurements meant study lead, University of Nottingham PhD student David Gee could develop a cost-effective and simple method to model groundwater rebound from the surface movement changes.

The study found a definitive link between ground motion measurements and rising mine water levels. Often land subsidence or uplift occurs as a result of changes in groundwater, where the strata acts a little like a sponge, expanding when filling with fluid and contracting when drained.

With near-complete spatial coverage of the InSAR data, he could fill in the measurement gaps between boreholes to map the change in mine water levels across the whole coalfield. The model takes into account both geology and depth of groundwater to determine the true rate of rebound and help identify where problems associated with rebound may occur.

The findings have been published in a paper 'Modelling groundwater rebound in recently abandoned coalfields using DInSAR' in the journal Remote Sensing of Environment.

David Gee, who is based in the Nottingham Geospatial Institute at the University, said, "There are several coalfields currently undergoing mine water rebound in the UK, where surface uplift has been measured using InSAR. In the Nottinghamshire coalfields, the quantitative comparison between the deformation measured by the model and InSAR confirms that the heave is caused by the recovery of mine water."

At first a forward model was generated to estimate surface uplift in response to measured changes in groundwater levels from monitoring boreholes. David calibrated and validated the model using ISBAS InSAR on ENVISAT and Sentinel-1 radar data. He then inverted the InSAR measurements to provide an estimate of the change in groundwater levels. Subsequently, the inverted rates were used to estimate the time it will take for groundwater to rebound and identify areas of the coalfield most at risk of surface discharges.

"InSAR measurements, when combined with modelling, can assist with the characterisation of the hydrogeological processes occurring at former mining sites. The technique has the potential to make a significant contribution to the progressive abandonment strategy of recently closed coalfields," David said.

The InSAR findings offer a supplementary source of data on groundwater changes that augment the borehole measurements. It means monitoring can be done remotely so is less labour-intensive for national bodies such as the Environment Agency (which manages hazards such as flooding, pollution and contaminated land) and the Coal Authority (which has a mandate to manage the legacy of underground coal mining in terms of public safety and subsidence).

The model has already flagged that some parts of the coal fields that are not behaving as previously predicted, which could influence existing remediation plans.

David explains, "The deepest part of the North Nottinghamshire coalfield, for example, is not rebounding as expected which suggests that the mine plans here might not be completely accurate. The stability is confirmed by the InSAR and the model -- future monitoring of this area will help to identify if or when rebound does eventually occur.

"Next steps for the project are to integrate our results into an existing screening tool developed by the Environment Agency and Coal Authority to help local planning authorities, developers and consultants design sustainable drainage systems in coalfield areas. The initial results, generated at a regional scale, have the potential to be scaled to all coalfields in the UK, with the aid of national InSAR maps," adds David.

Luke Bateson, Senior Remote Sensing Geologist from the British Geological Survey, said, "InSAR data offers a fantastic opportunity to reveal how the ground is moving, however we need studies such as David's in order to understand what these ground motions relate to and what they mean. David's study, not only provides this understanding but also provides a tool which can convert InSAR ground motions into information on mine water levels that can be used to make informed decisions."

Read more at Science Daily

Chronic alcohol use reshapes the brain's immune landscape, driving anxiety and addiction

 Deep within the brain, a small almond-shaped region called the amygdala plays a vital role in how we exhibit emotion, behavior and motivation. Understandably, it's also strongly implicated in alcohol abuse, making it a long-running focus of Marisa Roberto, PhD, professor in Scripps Research's Department of Molecular Medicine.

Now, for the first time, Roberto and her team have identified important changes to anti-inflammatory mechanisms and cellular activity in the amygdala that drive alcohol addiction. By countering this process in mice, they were able to stop excessive alcohol consumption -- revealing a potential treatment path for alcohol use disorder. The study is published in Progress in Neurobiology.

"We found that chronic alcohol exposure compromises brain immune cells, which are important for maintaining healthy neurons," says Reesha Patel, PhD, a postdoctoral fellow in Roberto's lab and first author of the study. "The resulting damage fuels anxiety and alcohol drinking that may lead to alcohol use disorder."

Roberto's study looked specifically at an immune protein called Interleukin 10, or IL-10, which is prevalent in the brain. IL-10 is known to have potent anti-inflammatory properties, which ensures that the immune system doesn't respond too powerfully to disease threats. In the brain, IL-10 helps to limit inflammation from injury or disease, such as stroke or Alzheimer's. But it also appears to influence key behaviors associated with chronic alcohol use.

In mice with chronic alcohol use, IL-10 was significantly reduced in the amygdala and didn't signal properly to neurons, contributing to increased alcohol intake. By boosting IL-10 signaling in the brain, however, the scientists could reverse the aberrant effects. Notably, they observed a stark reduction in anxiety-like behaviors and motivation to drink alcohol.

"We've shown that inflammatory immune responses in the brain are very much at play in the development and maintenance of alcohol use disorder," Roberto says. "But perhaps more importantly, we provided a new framework for therapeutic intervention, pointing to anti-inflammatory mechanisms."

Alcohol use disorder is widespread, affecting some 15 million people in the United States, and few effective treatments exist. By examining how brain cells change with prolonged exposure to alcohol, Roberto's lab has uncovered many possible new therapeutic approaches for those with alcohol addiction.

In the latest study, Roberto's lab collaborated with Silke Paust, PhD, associate professor in the Department of Immunology and Microbiology. Paust and her team determined the precise immune cells throughout the whole brain that are affected by chronic alcohol use. The findings revealed a large shift in the brain immune landscape, with increased levels of immune cells known as microglia and T-regulatory cells, which produce IL-10.

Despite a higher number of IL-10-producing cells in the whole brain of mice with prolonged alcohol use, the amygdala told a different story. In that region, levels of IL-10 were lower and their signaling function was compromised -- suggesting that the immune system in the amygdala responds uniquely to chronic alcohol use.

This study complements recent findings by the Roberto lab demonstrating a casual role for microglia in the development of alcohol dependence.

Read more at Science Daily

NASA's SpaceX Crew-1 astronauts headed to International Space Station

 

A SpaceX Falcon 9 rocket carrying the company's Crew Dragon spacecraft is launched on NASA's SpaceX Crew-1 mission to the International Space Station with NASA astronauts Mike Hopkins, Victor Glover, Shannon Walker, and Japan Aerospace Exploration Agency astronaut Soichi Noguchi onboard, Sunday, Nov. 15, 2020, at NASA's Kennedy Space Center in Florida. NASA's SpaceX Crew-1 mission is the first crew rotation mission of the SpaceX Crew Dragon spacecraft and Falcon 9 rocket to the International Space Station as part of the agency's Commercial Crew Program. Hopkins, Glover, Walker, and Noguchi launched at 7:27 p.m. EST from Launch Complex 39A at the Kennedy Space Center to begin a six month mission onboard the orbital outpost.

An international crew of astronauts is en route to the International Space Station following a successful launch on the first NASA-certified commercial human spacecraft system in history. NASA's SpaceX Crew-1 mission lifted off at 7:27 p.m. EST Sunday from Launch Complex 39A at the agency's Kennedy Space Center in Florida.

The SpaceX Falcon 9 rocket propelled the Crew Dragon spacecraft with NASA astronauts Michael Hopkins, Victor Glover, and Shannon Walker, along with Soichi Noguchi of the Japan Aerospace Exploration Agency (JAXA), into orbit to begin a six-month science mission aboard the space station.

"NASA is delivering on its commitment to the American people and our international partners to provide safe, reliable, and cost-effective missions to the International Space Station using American private industry," said NASA Administrator Jim Bridenstine. "This is an important mission for NASA, SpaceX and our partners at JAXA, and we look forward to watching this crew arrive at station to carry on our partnership for all of humanity."

The Crew Dragon spacecraft, named Resilience, will dock autonomously to the forward port of the station's Harmony module about 11 p.m. Monday, Nov. 16. NASA Television and the agency's website are providing ongoing live coverage through docking, hatch opening, and the ceremony to welcome the crew aboard the orbiting laboratory.

"I could not be more proud of the work we've done here today," said Gwynne Shotwell, president and chief operating officer of SpaceX. "Falcon 9 looked great, Dragon was dropped off into a beautiful orbit about 12 minutes into the mission, and we'll get more data as we go."

The Crew-1 mission is the first of six crewed missions NASA and SpaceX will fly as part of the agency's Commercial Crew Program. This mission has several firsts, including:
 

• The first flight of the NASA-certified commercial system designed for crew transportation, which moves the system from development into regular flights;
• The first international crew of four to launch on an American commercial spacecraft;
• The first time the space station's long duration expedition crew size will increase from six to seven crew members, which will add to the crew time available for research; and
• The first time the Federal Aviation Administration has licensed a human orbital spaceflight launch.

The astronauts named the Crew Dragon spacecraft Resilience, highlighting the dedication teams involved with the mission have displayed and to demonstrate that when we work together, there is no limit to what we can achieve. They named it in honor of their families, colleagues, and fellow citizens.

"Watching this mission launch is a special moment for NASA and our SpaceX team," said Steve Stich, manager of NASA's Commercial Crew Program. "We are looking forward to getting this crew to station to continue our important work, and I want to thank the teams for the amazing effort to make the next generation of human space transportation possible."

During flight, SpaceX commands the spacecraft from its mission control center in Hawthorne, California, and NASA teams monitor space station operations throughout the flight from the Mission Control Center at the agency's Johnson Space Center in Houston.

Hopkins, Glover, Walker, and Noguchi will join the Expedition 64 crew of Commander Sergey Ryzhikov and Flight Engineer Sergey Kud-Sverchkov, both of the Russian space agency Roscosmos, and Flight Engineer Kate Rubins of NASA.

"It is an honor to have our Japanese astronaut launch on this Crew-1 Dragon as the first astronaut of the International Partner participating in the ISS program," said Hiroshi Sasaki, JAXA vice president. "We look forward to having him conduct lots of science and demonstrate the technology, for here on Earth and for the future. I would also like to thank NASA and SpaceX for their tremendous effort to make this happen."

Rubins, Hopkins, Glover, Walker, and Noguchi will participate in a live crew news conference from orbit at 9:55 a.m. Thursday, Nov. 19, on NASA TV and the agency's website.

Crew-1 Astronauts

Michael Hopkins is commander of the Crew Dragon spacecraft and the Crew-1 mission. Hopkins is responsible for all phases of flight, from launch to re-entry. He also will serve as an Expedition 64 flight engineer aboard the station. Selected as a NASA astronaut in 2009, Hopkins spent 166 days in space as a long-duration crew member of Expeditions 37 and 38 and completed two spacewalks totaling 12 hours and 58 minutes. Born in Lebanon, Missouri, Hopkins grew up on a farm outside Richland, Missouri. He has a bachelor's degree in aerospace engineering from the University of Illinois, and a master's degree in aerospace engineering from Stanford University. Before joining NASA, Hopkins was a flight test engineer with the U.S. Air Force.

Victor Glover is the pilot of the Crew Dragon spacecraft and second-in-command for the mission. Glover is responsible for spacecraft systems and performance. He also will be a long-duration space station crew member. Selected as an astronaut in 2013, this is his first spaceflight.

The California native holds a Bachelor of Science degree in general engineering from California Polytechnic State University, a Master of Science degree in flight test engineering and a master's degree military operational art and science from Air University, and a Master of Science degree in systems engineering from Naval Postgraduate School. Glover is a naval aviator and was a test pilot in the F/A‐18 Hornet, Super Hornet, and EA‐18G Growler aircraft.

Shannon Walker is a mission specialist for Crew-1. As a mission specialist, she works closely with the commander and pilot to monitor the vehicle during the dynamic launch and re-entry phases of flight. She also is responsible for monitoring timelines, telemetry, and consumables. Once aboard the station, Walker will become a flight engineer for Expedition 64. Selected as a NASA astronaut in 2004, Walker launched to the International Space Station aboard the Russian Soyuz TMA-19 spacecraft as the co-pilot, and spent 161 days aboard the orbiting laboratory. More than 130 microgravity experiments were conducted during her stay in areas such as human research, biology, and materials science. A Houston native, Walker received a Bachelor of Arts degree in physics from Rice University, as well as a Master of Science degree and a doctorate in space physics, both from Rice University, in 1992 and 1993, respectively.

Soichi Noguchi also is a mission specialist for Crew-1, working with the commander and pilot to monitor the vehicle during the dynamic launch and re-entry phases of flight, and keeping watch on timelines, telemetry and consumables. Noguchi also will become a long-duration crew member aboard the space station. He was selected as an astronaut candidate by the National Space Development Agency of Japan (NASDA, currently the Japan Aerospace Exploration Agency) in May 1996. Noguchi is a veteran of two spaceflights. During STS-114 in 2005, Noguchi became the first Japanese astronaut to perform a spacewalk outside the space station. He performed a total of three spacewalks during the mission, accumulating 20 hours and 5 minutes of spacewalking time. He launched aboard a Soyuz spacecraft in 2009, to return to the station as a long-duration crew member. The Crew Dragon will be the third spacecraft Noguchi has flown to the orbiting laboratory.

Mission Objectives

The crew will conduct science and maintenance during a six-month stay aboard the orbiting laboratory and will return in spring 2021. It is scheduled to be the longest human space mission launched from the United States. The Crew Dragon spacecraft is capable of staying in orbit for at least 210 days, as a NASA requirement.

Crew Dragon also is delivering more than 500 pounds of cargo, new science hardware and experiments inside, including Food Physiology, a study of the effects of an optimized diet on crew health and, Genes in Space-7, a student-designed experiment that aims to better understand how spaceflight affects brain function, enabling scientists to keep astronauts healthy as they prepare for long-duration missions in low-Earth orbit and beyond.

Among the science and research investigations the crew will support during its six-month mission are a study using chips with tissue that mimics the structure and function of human organs to understand the role of microgravity on human health and diseases and translate those findings to improve human health on Earth, growing radishes in different types of light and soils as part of ongoing efforts to produce food in space, and testing a new system to remove heat from NASA's next generation spacesuit, the Exploration Extravehicular Mobility Unit (xEMU).

During their stay on the orbiting laboratory, Crew-1 astronauts expect to see a range of uncrewed spacecraft including the next generation of SpaceX cargo Dragon spacecraft, the Northrop Grumman Cygnus, and the Boeing CST-100 Starliner on its uncrewed flight test to the station. They also will conduct a variety of spacewalks and welcome crews of the Russian Soyuz vehicle and the next SpaceX Crew Dragon in 2021.

At the conclusion of the mission, the Crew-1 astronauts will board Crew Dragon, which will then autonomously undock, depart the space station, and re-enter Earth's atmosphere. Crew Dragon also will return to Earth important and time-sensitive research. NASA and SpaceX are capable of supporting seven splashdown sites located off Florida's east coast and in the Gulf of Mexico. Upon splashdown, the SpaceX recovery ship will pick up the crew and return to shore.

NASA's Commercial Crew Program is delivering on its goal of safe, reliable, and cost-effective transportation to and from the International Space Station from the United States through a partnership with American private industry. This partnership is changing the arc of human spaceflight history by opening access to low-Earth orbit and the International Space Station to more people, more science, and more commercial opportunities.

Read more at Science Daily

Cysteine synthesis was a key step in the origin of life

 In an important step during the early evolution of life on Earth, the formation of the amino acid cysteine delivered vital catalysts, which enabled the earliest protein molecules to form in water, according to a new study by UCL researchers.

All proteins are built from the same 20 amino acids. One of these, cysteine, was assumed not to have been present at the origin of life. Despite its fundamental importance to all life today, it was unclear how cysteine might have formed on the early Earth.

In a new study, published in Science, UCL scientists have recreated how cysteine was formed at the origins of life. Additionally, they have observed how, once formed, cysteine catalyses the fusion of peptides in water -- a fundamental step in the path towards protein enzymes.

The UCL researchers created cysteine using very simple chemistry and chemicals -- hydrogen cyanide and hydrogen sulfide -- that were likely to be abundant on the early Earth. The route that they have unravelled closely resembles how cysteine is synthesised in living organisms today, and the researchers believe they are historically linked.

The study also found that cysteine residues catalyse peptide synthesis in water by joining together short peptide fragments that the team had previously found in a study published in Nature last year.

Senior author Professor Matthew Powner (UCL Chemistry) said: "Our results show how cysteine may have formed on the early Earth and how it could have played a critical role in the evolution of protein synthesis.

"Once formed, cysteine catalysts behave as 'proto-enzymes' to produce peptides in water. This robust chemistry could have generated peptides long enough to fold into enzyme-like structures, which would be the precursors to the protein enzymes that are fundamental to all living organisms."

Co-lead author and Research Fellow Dr Saidul Islam (UCL Chemistry) said: "We have shown that nitriles possess the in-built energy required to form peptide bonds in water. This is the simplest way of making peptides that works with all of the 20 amino acids, which makes it all the more incredible.

"It is precisely the sort of simple, yet special, chemistry that was essential to kick-start life several billion years ago. Our study provides further evidence that the molecules of life descended from nitrile chemistry on the early Earth."

Co-lead author Dr Callum Foden, who completed the work while a PhD student at UCL, said: "The peptide synthesis we discovered is simple, highly selective and uses molecules that were available on the early Earth.

"A single cysteine residue is enough to produce robust catalytic activity. It is remarkable that such small molecules can carry out such an important (bio)chemical reaction, selectively in water, at neutral pH, and in such high yields."

Discussing further implications of their study, Professor Powner said: "We have resolved a long-standing problem for the origin of life by providing a simple solution to catalytic peptide synthesis in water. Importantly, the catalysts are built only from biology's amino acids. Understanding how cysteine could have controlled the formation of Earth's earliest peptides has made the long path from chemistry to a living organism seem a little shorter, and a little less daunting.

Read more at Science Daily

Go (over) easy on the eggs: 'Egg-cess' consumption linked to diabetes

 Scrambled, poached or boiled, eggs are a popular breakfast food the world over. Yet the health benefits of the humble egg might not be all they're cracked up to be as new research from the University of South Australia shows that excess egg consumption can increase your risk of diabetes.

Conducted in partnership with the China Medical University, and Qatar University, the longitudinal study (1991 to 2009) is the first to assess egg consumption in a large sample of Chinese adults.

It found that people who regularly consumed one or more eggs per day (equivalent to 50 grams) increased their risk of diabetes by 60 per cent.

With the prevalence of diabetes in China now exceeding 11 per cent -- above that of the global average of 8.5 per cent -- diabetes has become a serious public health concern.

The economic impact of diabetes is also significant, accounting for 10 per cent of global health expenditure (USD $760 billion). In China, diabetes-related costs have exceeded USD $109 billion.

Epidemiologist and public health expert, UniSA's Dr Ming Li, says the rise of diabetes is a growing concern, especially in China where changes to the traditional Chinese diet are impacting health.

"Diet is a known and modifiable factor that contributes to the onset Type 2 diabetes, so understanding the range of dietary factors that might impact the growing prevalence of the disease is important," Dr Li says.

"Over the past few decades China has undergone a substantial nutritional transition that's seen many people move away from a traditional diet comprising grains and vegetables, to a more processed diet that includes greater amounts of meat, snacks and energy-dense food.

"At the same time, egg consumption has also been steadily increasing; from 1991 to 2009, the number of people eating eggs in China nearly doubled*.

"While the association between eating eggs and diabetes is often debated, this study has aimed to assess people's long-term egg consumption of eggs and their risk of developing diabetes, as determined by fasting blood glucose.

"What we discovered was that higher long-term egg consumption (greater than 38 grams per day) increased the risk of diabetes among Chinese adults by approximately 25 per cent.

"Furthermore, adults who regularly ate a lot of eggs (over 50 grams, or equivalent to one egg, per day) had an increased risk of diabetes by 60 per cent."

The effect was also more pronounced in women than in men.

Dr Li says that while these results suggest that higher egg consumption is positively associated with the risk of diabetes in Chinese adults, more research is needed to explore causal relationships.

Read more at Science Daily