New species of stegosaur is oldest discovered in Asia, and possibly the world

Relatively small, but fearsome-looking stegosaur measured about 2.8 metres (9 feet) from nose to tail -- but scientists can't tell whether the remains are those of an adult or juvenile.

A new species of one of the most recognisable types of dinosaur is the oldest stegosaur ever found in Asia, and one of the earliest unearthed anywhere in the world, according to research published today in the peer-reviewed Journal of Vertebrate Paleontology.

Remains of the stegosaur, which included bones from the back, shoulder, thigh, feet, and ribs, as well as several armour plates, date to the Bajocian stage of the Middle Jurassic period -- much earlier than most known stegosaurs.

A team from the Chongqing Bureau of Geological and Mineral Resource Exploration and Development in China and London's Natural History Museum named it Bashanosaurus primitivus - "Bashan" in reference to the ancient name for the area of Chongqing in China where the dinosaur was found, and the Latin for 'first' -- primitivus.

The new dinosaur, which roamed the planet 168 million years ago, plays a part in uncovering how the stegosaurs evolved -- of which, to this day, little is known.

It has a smaller and less developed should blade, narrower and thicker bases to its armour plates and other features that are different from all other Middle Jurassic stegosaurs discovered so far. However, it does have similarities with some of the first armoured dinosaurs, which are over 20 million years older.

"All these features are clues to the stegosaurs' place on the dinosaur family tree," says Dr Dai Hui from Chongqing Bureau of Geological and Mineral Resource Exploration and Development who led the research. "Bashanosaurus can be distinguished fromother Middle Jurassic stegosaurs, and clearly represents a new species.

"What's more, our analysis of the family tree indicates that it is one of the earliest-diverging stegosaurs along with the Chongqing Lizard (Chungkingosaurus) and Huayangosaurus. These were all unearthed from the Middle to Late Jurassic Shaximiao Formation in China, suggesting that stegosaurs might have originated in Asia," adds Hui.

Instantly recognisable by the huge back plates, long tail spikes and tiny head, stegosaurs were four-legged, plant-eating dinosaurs that lived during the Jurassic and early Cretaceous periods. Stegosaur fossils have been found on all continents except for Antarctica and Australia, and 14 species of stegosaur have been identified so far.

Well-known members of Stegosauria include Huayangosaurus (one of the most primitive stegosaurs), Gigantspinosaurus, notable for its enormous shoulder spines, and Miragaia for its extremely long neck. However, the fragmentary fossil material has hindered attempts to understand how the stegosaurs evolved and how they relate to one another.

With the discovery of this new species the mystery has started to clear up. Bashanosaurus primitivus has several primitive features that are similar to the earliest stegosaurs like Huayangosaurus and Gigantspinosaurus and early-branching thyreophorans (armoured dinosaurs). These include longer tail vertebrae, a shoulder blade that is narrower and flares out, and features of the back vertebrae that are similar to the early armoured dinosaur Scelidosaurus, which lived during the Early Jurassic.

The fossilised remains of Bashanosaurus also reveal a host of features that make it unique from other known stegosaurs. For example, the bony point at the end of the shoulder blade is small and less well developed than in other stegosaurs; a bony projection of the thighbone (fourth trochanter) is positioned below the middle of the shaft; and the bases of the armour plates curve outwards and are thicker than the plates on the backs of its later relatives.

"The discovery of this stegosaur from the Middle Jurassic of China adds to an increasing body of evidence that the group evolved in the early Middle Jurassic, or perhaps even in the Early Jurassic, and as such represent some of the earliest known bird-hipped dinosaurs," says Dr Susannah Maidment, co-author and palaeontologist at London's Natural History Museum.

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More alcohol, less brain: Association begins with an average of just one drink a day

 Even light-to-moderate drinking is associated with harm to the brain, according to a new study. Researchers analyzed data from more than 36,000 adults that found a link between drinking and reduced brain volume that begins at an average consumption level of less than one alcohol unit a day -- the equivalent of about half a beer -- and rises with each additional drink.

The research, using a dataset of more than 36,000 adults, revealed that going from one to two drinks a day was linked with changes in the brain equivalent to aging two years. Heavier drinking was associated with an even greater toll. The science on heavy drinking and the brain is clear: The two don't have a healthy relationship. People who drink heavily have alterations in brain structure and size that are associated with cognitive impairments.

But according to a new study, alcohol consumption even at levels most would consider modest -- a few beers or glasses of wine a week -- may also carry risks to the brain. An analysis of data from more than 36,000 adults, led by a team from the University of Pennsylvania, found that light-to-moderate alcohol consumption was associated with reductions in overall brain volume.

The link grew stronger the greater the level of alcohol consumption, the researchers showed. As an example, in 50-year-olds, as average drinking among individuals increases from one alcohol unit (about half a beer) a day to two units (a pint of beer or a glass of wine) there are associated changes in the brain equivalent to aging two years. Going from two to three alcohol units at the same age was like aging three and a half years. The team reported their findings in the journal Nature Communications.

"The fact that we have such a large sample size allows us to find subtle patterns, even between drinking the equivalent of half a beer and one beer a day," says Gideon Nave, a corresponding author on the study and faculty member at Penn's Wharton School. He collaborated with former postdoc and co-corresponding author Remi Daviet, now at the University of Wisconsin-Madison, and Perelman School of Medicine colleagues Reagan Wetherill -- also a corresponding author on the study -- and Henry Kranzler, as well as other researchers.

"These findings contrast with scientific and governmental guidelines on safe drinking limits," says Kranzler, who directs the Penn Center for Studies of Addiction. "For example, although the National Institute on Alcohol Abuse and Alcoholism recommends that women consume an average of no more than one drink per day, recommended limits for men are twice that, an amount that exceeds the consumption level associated in the study with decreased brain volume,"

Ample research has examined the link between drinking and brain health, with ambiguous results. While strong evidence exists that heavy drinking causes changes in brain structure, including strong reductions in gray and white matter across the brain, other studies have suggested that moderate levels of alcohol consumption may not have an impact, or even that light drinking could benefit the brain in older adults.

These earlier investigations, however, lacked the power of large datasets. Probing massive quantities of data for patterns is the specialty of Nave, Daviet, and colleagues, who have conducted previous studies using the UK Biobank, a dataset with genetic and medical information from half a million British middle-aged and older adults. They employed biomedical data from this resource in the current study, specifically looking at brain MRIs from more than 36,000 adults in the Biobank, which can be used to calculate white and gray matter volume in different regions of the brain.

"Having this dataset is like having a microscope or a telescope with a more powerful lens," Nave says. "You get a better resolution and start seeing patterns and associations you couldn't before."

To gain an understanding of possible connections between drinking and the brain, it was critical to control for confounding variables that could cloud the relationship. The team controlled for age, height, handedness, sex, smoking status, socioeconomic status, genetic ancestry, and county of residence. They also corrected the brain-volume data for overall head size.

The volunteer participants in the Biobank had responded to survey questions about their alcohol consumption levels, from complete abstention to an average of four or more alcohol units a day. When the researchers grouped the participants by average-consumption levels, a small but apparent pattern emerged: The gray and white matter volume that might otherwise be predicted by the individual's other characteristics was reduced.

Going from zero to one alcohol units didn't make much of a difference in brain volume, but going from one to two or two to three units a day was associated with reductions in both gray and white matter.

"It's not linear," says Daviet. "It gets worse the more you drink."

Even removing the heavy drinkers from the analyses, the associations remained. The lower brain volume was not localized to any one brain region, the scientists found.

To give a sense of the impact, the researchers compared the reductions in brain size linked with drinking to those that occur with aging. Based on their modeling, each additional alcohol unit consumed per day was reflected in a greater aging effect in the brain. While going from zero to a daily average of one alcohol unit was associated with the equivalent of a half a year of aging, the difference between zero and four drinks was more than 10 years of aging.

In future work, the authors hope to tap the UK Biobank and other large datasets to help answer additional questions related to alcohol use. "This study looked at average consumption, but we're curious whether drinking one beer a day is better than drinking none during the week and then seven on the weekend," Nave says. "There's some evidence that binge drinking is worse for the brain, but we haven't looked closely at that yet."

They'd also like to be able to more definitively pin down causation rather than correlation, which may be possible with new longitudinal biomedical datasets that are following young people as they age.

"We may be able to look at these effects over time and, along with genetics, tease apart causal relationships," Nave says.

And while the researchers underscore that their study looked only at correlations, they say the findings may prompt drinkers to reconsider how much they imbibe.

"There is some evidence that the effect of drinking on the brain is exponential," says Daviet. "So, one additional drink in a day could have more of an impact than any of the previous drinks that day. That means that cutting back on that final drink of the night might have a big effect in terms of brain aging."

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Did rapid spin delay 2017 collapse of merged neutron stars into black hole?

When two neutron stars spiral into one another and merge to form a black hole -- an event recorded in 2017 by gravitational wave detectors and telescopes worldwide -- does it immediately become a black hole? Or does it take a while to spin down before gravitationally collapsing past the event horizon into a black hole?

Ongoing observations of that 2017 merger by the Chandra X-ray Observatory, an orbiting telescope, suggests the latter: that the merged object stuck around, likely for a mere second, before undergoing ultimate collapse.

The evidence is in the form of an X-ray afterglow from the merger, dubbed GW170817, that would not be expected if the merged neutron stars collapsed immediately to a black hole. The afterglow can be explained as a rebound of material off the merged neutron stars, which plowed through and heated the material around the binary neutron stars. This hot material has now kept the remnant glowing steadily more than four years after the merger threw material outward in what's referred to as a kilonova. X-ray emissions from a jet of material that was detected by Chandra shortly after the merger would otherwise be dimming by now.

While the excess X-ray emissions observed by Chandra could come from debris in an accretion disk swirling around and eventually falling into the black hole, astrophysicist Raffaella Margutti of the University of California, Berkeley, favors the delayed collapse hypothesis, which is predicted theoretically.

"If the merged neutron stars were to collapse directly to a black hole with no intermediate stage, it would be very hard to explain this X-ray excess that we see right now, because there would be no hard surface for stuff to bounce off and fly out at high velocities to create this afterglow," said Margutti, UC Berkeley associate professor of astronomy and of physics. "It would just fall in. Done. The true reason why I'm excited scientifically is the possibility that we are seeing something more than the jet. We might finally get some information about the new compact object."

Margutti and her colleagues, including first author Aprajita Hajela, who was Margutti's graduate student when she was at Northwestern University before moving to UC Berkeley, report their analysis of the X-ray afterglow in a paper recently accepted for publication in The Astrophysical Journal Letters.

The radioactive glow of a kilonova

Gravitational waves from the merger were first detected on Aug. 17, 2017, by the Advanced Laser Interferometer Gravitational-wave Observatory (LIGO) and the Virgo collaboration. Satellite- and ground-based telescopes quickly followed up to record a burst of gamma rays and visible and infrared emissions that together confirmed the theory that many heavy elements are produced in the aftermath of such mergers inside hot ejecta that produces a bright kilonova. The kilonova glows because of light emitted during the decay of radioactive elements, like platinum and gold, that are produced in the merger debris.

Chandra, too, pivoted to observe GW170817, but saw no X-rays until nine days later, suggesting that the merger also produced a narrow jet of material that, upon colliding with the material around the neutron stars, emitted a cone of X-rays that initially missed Earth. Only later did the head of the jet expand and begin emitting X-rays in a broader jet visible from Earth.

The X-ray emissions from the jet increased for 160 days after the merger, after which they steadily grew fainter as the jet slowed down and expanded. But Hajela and her team noticed that from March 2020 -- about 900 days after the merger -- until the end of 2020, the decline stopped, and the X-ray emissions remained approximately constant in brightness.

"The fact that the X-rays stopped fading quickly was our best evidence yet that something in addition to a jet is being detected in X-rays in this source," Margutti said. "A completely different source of X-rays appears to be needed to explain what we're seeing."

The researchers suggest that the excess X-rays are produced by a shock wave distinct from the jets produced by the merger. This shock was a result of the delayed collapse of the merged neutron stars, likely because its rapid spin very briefly counteracted the gravitational collapse. By sticking around for an extra second, the material around the neutron stars got an extra bounce that produced a very fast tail of kilonova ejecta that created the shock.

"We think the kilonova afterglow emission is produced by shocked material in the circumbinary medium," Margutti said. "It is material that was in the environment of the two neutron stars that was shocked and heated up by the fastest edge of the kilonova ejecta, which is driving the shock wave."

The radiation is reaching us only now because it took time for the heavy kilonova ejecta to be decelerated in the low-density environment and for the kinetic energy of the ejecta to be converted into heat by shocks, she said. This is the same process that produces radio and X-rays for the jet, but because the jet is much, much lighter, it is immediately decelerated by the environment and shines in the X-ray and radio from the very earliest times.

An alternative explanation, the researchers note, is that the X-rays come from material falling towards the black hole that formed after the neutron stars merged.

"This would either be the first time we've seen a kilonova afterglow or the first time we've seen material falling onto a black hole after a neutron star merger," said co-author Joe Bright, a UC Berkeley postdoctoral researcher. "Either outcome would be extremely exciting."

Chandra is now the only observatory still able to detect light from this cosmic collision. Follow-up observations by Chandra and radio telescopes could distinguish between the alternative explanations, however. If it is a kilonova afterglow, radio emission is expected to be detected again in the next few months or years. If the X-rays are being produced by matter falling onto a newly formed black hole, then the X-ray output should stay steady or decline rapidly, and no radio emission will be detected over time.

Margutti hopes that LIGO, Virgo and other telescopes will capture gravitational waves and electromagnetic waves from more neutron star mergers so that the series of events preceding and following the merger can be pinned down more precisely and help reveal the physics of black hole formation. Until then, GW170817 is the only example available for study.

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New research suggests a causal link between blood group and severe COVID-19

A new study has analysed over 3000 proteins to identify which are causally linked to the development of severe COVID-19. This is the first study to assess such a large number of proteins for their connection to COVID-19. The findings provide insight into potential new targets for approaches to treat and prevent severe COVID-19.

Published in PLOS Genetics and part-funded by the National Institute for Health Research (NIHR) Maudsley Biomedical Research Centre, the study used a genetic tool to screen over 3000 proteins. Researchers identified six proteins that could underlie an increased risk of severe COVID-19 and eight that could contribute to protection from severe COVID-19.

One of the proteins (ABO) that was identified as having a causal connection to the risk of developing severe COVID-19 determines blood groups, suggesting that blood groups play an instrumental role in whether people develop severe forms of the disease.

Co-first author Dr Alish Palmos from Institute of Psychiatry, Psychology & Neuroscience (IoPPN) King's College London said: "We have used a purely genetic approach to investigate a large number of blood proteins and established that a handful have causal links to the development of severe COVID-19. Honing in on this group of proteins is a vital first step in discovering potentially valuable targets for development of new treatments."

Assessing how blood proteins are linked to disease can help understand the underlying mechanisms and identify potential new targets for developing or repurposing drugs. Protein levels can be measured directly from blood samples but conducting this type of research for large numbers of proteins is costly and cannot establish causal direction.

This is where genetics can play a role. Mendelian randomisation, a method of comparing causal relations between risk factors and health outcomes, using large genetic datasets can assess the relationship between genetic variants connected with an exposure (in this case high levels of individual blood proteins) and genetic variants connected with disease outcome (in this case severe COVID-19).

Co-first author Dr Vincent Millischerfrom the Medical University of Vienna explained: "Causality between exposure and disease can be established because genetic variants inherited from parent to offspring are randomly assigned at conception similar to how a randomised controlled trial assigns people to groups. In our study the groups are defined by their genetic propensity to different blood protein levels, allowing an assessment of causal direction from high blood protein levels to COVID-19 severity whilst avoiding influence of environmental effects."

The study considered two incremental levels of severity of COVID-19: hospitalisation and respiratory support or death. Using data from a number of genome-wide association studies the researchers found six proteins that were causally linked to an increased risk of hospitalisation or respiratory support/death due to COVID-19 and eight causally linked to protection against hospitalisation or respiratory support/death.

Analysis showed some distinction in types of proteins linked to hospitalisation and those linked to respiratory support/death, indicating different mechanisms may be at work in these two stages of disease.

The analysis identified that an enzyme (ABO) that determines blood group was causally associated with both an increased risk of hospitalisation and a requirement for respiratory support. This supports previous findings around the association of blood group with higher likelihood of death. Taken together with previous research showing that the proportion of group A is higher in COVID-19 positive individuals, this suggests blood group A is candidate for follow-up studies.

Co-last author Dr Christopher Hübelfrom the IoPPN, King's College London said: "The enzyme helps determine the blood group of an individual and our study has linked it with both risk of hospitalisation and the need of respiratory support or death. Our study does not link precise blood group with risk of severe COVID-19 but since previous research has found that proportion of people who are group A is higher in COVID-19 positive individuals, this suggests that blood group A is more likely candidate for follow-up studies."

Researchers also identified three adhesion molecules as being causally linked to a decreased risk of hospitalisation and requirement of respiratory support. As these adhesion molecules mediate interaction between immune cells and blood vessels this chimes with previous research suggesting that late stage COVID-19 is also a disease involving the linings of blood vessels.

By identifying this suite of proteins, the research has highlighted a number possible targets for drugs that could be used to help treat severe COVID-19. These will need further clinical investigation which can be undertaken as part of the wider COVID-Clinical Neuroscience Study (COVID-CNS) which is investigating the causes behind different aspects of COVID-19.

Gerome Breen, Professor of Genetics at the IoPPN, and co-last author on the paper said: "What we have done in our study is provide a shortlist for the next stage of research. Out of 1000s of blood proteins we have whittled it down to about 14 that have some form of causal connection to the risk of severe COVID-19 and present a potentially important avenue for further research to better understand the mechanisms behind COVID-19 with an ultimate aim of developing new treatments but potentially also preventative therapies."

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Single test for over 50 genetic diseases will cut diagnosis from decades to days

A new DNA test, developed by researchers at the Garvan Institute of Medical Research in Sydney and collaborators from Australia, UK and Israel, has been shown to identify a range of hard-to-diagnose neurological and neuromuscular genetic diseases quicker and more-accurately than existing tests.

'We correctly diagnosed all patients with conditions that were already known, including Huntington's disease, fragile X syndrome, hereditary cerebellar ataxias, myotonic dystrophies, myoclonic epilepsies, motor neuron disease and more,' says Dr Ira Deveson, Head of Genomics Technologies at the Garvan Institute and senior author of the study.

The diseases covered by the test belong to a class of over 50 diseases caused by unusually-long repetitive DNA sequences in a person's genes -- known as 'Short Tandem Repeat (STR) expansion disorders'.

'They are often difficult to diagnose due to the complex symptoms that patients present with, the challenging nature of these repetitive sequences, and limitations of existing genetic testing methods,' says Dr Deveson.

The study, published today in Science Advances, shows that the test is accurate, and allows the team to begin validations to make the test available in pathology services around the world.

A patient who participated in the study, John, first realised something wrong when he experienced unusual problems balancing during a ski lesson.

'It was very worrying having symptoms that, over the years, increased in severity; from being active and mobile to not being able to walk without support. I had test after test for over ten years and absolutely no answers as to what was wrong,' says John, who was eventually diagnosed with a rare genetic disease called CANVAS, which affects the brain.

'It was reassuring to finally confirm my diagnosis genetically, and it's exciting to know that, in the near future, others with these types of conditions will be able to get a diagnosis quicker than I did,' he says.

'For patients like John, the new test will be a game-changer, helping to end what can often be a taxing diagnostic odyssey,' says Dr Kishore Kumar, a co-author of the study and clinical neurologist at the Concord Hospital.

Repeat expansion disorders can be passed on through families, can be life threatening and generally involve muscle and nerve damage, as well as other complications throughout the body.

Quicker, more-accurate diagnosis for patients avoids 'diagnostic odyssey'

Current genetic testing for expansion disorders can be 'hit and miss', says Dr Kumar. 'When patients present with symptoms, it can be difficult to tell which of these 50-plus genetic expansions they might have, so their doctor must decide which genes to test for based on the person's symptoms and family history. If that test comes back negative, the patient is left without answers. This testing can go on for years without finding the genes implicated in their disease. We call this the 'diagnostic odyssey', and it can be quite stressful for patients and their families,' he says.

'This new test will completely revolutionise how we diagnose these diseases, since we can now test for all the disorders at once with a single DNA test and give a clear genetic diagnosis, helping patients avoid years of unnecessary muscle or nerve biopsies for diseases they don't have, or risky treatments that suppress their immune system,' says Dr Kumar.

Although repeat expansion disorders cannot be cured, a quicker diagnosis can help doctors identify and treat disease complications earlier, such as heart issues associated with Friedreich's ataxia.

Scanning for known and novel diseases

Using a single DNA sample, usually extracted from blood, the test works by scanning a patient's genome using a technology called Nanopore sequencing.

'We've programmed the Nanopore device to hone in on the roughly 40 genes known to be involved in these disorders and to read through the long, repeated DNA sequences that cause disease,' he says. 'By unravelling the two strands of DNA and reading the repeated letter sequences (combinations of A, T, G or C), we can scan for abnormally long repeats within the patient's genes, which are the hallmarks of disease.'

'In the one test, we can search for every known disease-causing repeat expansion sequence, and potentially discover novel sequences likely to be involved in diseases that have not yet been described,' says Dr Deveson.

Upscaling to wider use in the next five years

The Nanopore technology used in the test is smaller and cheaper than standard tests, which the team hopes will smooth its uptake into pathology labs. 'With Nanopore, the gene sequencing device has been reduced from the size of a fridge to the size of a stapler, and costs around $1000, compared with hundreds of thousands needed for mainstream DNA sequencing technologies' says Dr Deveson.

The team expects to see their new technology used in diagnostic practice within the next two to five years. One of the key steps towards that goal is to gain appropriate clinical accreditation for the method.

Once accredited, the test will also transform research into genetic diseases, says Dr Gina Ravenscroft, a co-author of the study and a researcher working on rare disease genetics at the Harry Perkins Institute of Medical Research.

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Potato genome decoded

More than 20 years after the first releasse of the human genome, scientists at the Ludwig-Maximilians-Universität München and the Max Planck Institute for Plant Breeding Research in Cologne, have for the first time decoded the highly complex genome of the potato. This technically demanding study lays the biotechnological foundation to accelerate the breeding of more robust varieties -- a goal in plant breeding for many years and an important step for global food security.

When shopping for potatoes on a market today, buyers may well be going home with a variety that was already available more than 100 years ago. Traditional potato varieties are popular. And yet this example also highlights a lack of diversity among the predominant potato varieties. However, that could soon change: researchers in the group of geneticist Korbinian Schneeberger were able to generate the first full assembly of a potato genome. This paves the way for breeding new, robust varieties:

"The potato is becoming more and more integral to diets worldwide including even Asian countries like China where rice is the traditional staple food. Building on this work, we can now implement genome-assisted breeding of new potato varieties that will be more productive and also resistant to climate change -- this could have a huge impact on delivering food security in the decades to come."

Especially the low diversity makes potato plants susceptible to diseases. This can have stark consequences, most dramatically during the Irish famine of the 1840s, where for several years nearly the entire potato crop rotted in the ground, and millions of people in Europe suffered from starvation simply because the single variety that was grown was not resistant to newly emerging tuber blight. During the Green Revolution of the 1950s and 1960s, scientists and plant breeders succeeded in achieving large increases in the yields of many of our major crop staples like rice or wheat. However, the potato has seen no comparable boost, and efforts to breed new varieties with higher yields have remained largely unsuccessful to the current day.

The reason for this is simple but has proven difficult to tackle -- instead of inheriting one copy of every chromosome from both the father and from the mother (as in humans) potatoes inherit two copies of each chromosome from each parent, making them a species with four copies of each chromosome (tetraploid). Four copies of each chromosome also mean four copies of each gene, and this makes it highly challenging and time-consuming to generate new varieties that harbour a desired combination of individual properties; what's more, multiple copies of each chromosome also make the reconstruction of the potato genome a far greater technical challenge than was the case for the human genome.

The researchers have overcome this longstanding hurdle using a simple yet elegant trick. Instead of trying to differentiate the four, often very similar, chromosome copies from each other, Korbinian Schneeberger together with his colleague Hequan Sun and other co-workers circumvented this problem by sequencing the DNA of large numbers of individual pollen cells. In contrast to all other cells, each pollen cell contains only two random copies of each chromosome; this facilitated the reconstruction of the sequence of the entire genome.

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Powerful warm winds seen blowing from a neutron star as it rips up its companion

Using the most powerful telescopes on Earth and in space, a team of astronomers has found for the first time blasts of hot, warm and cold winds from a neutron star whilst it consumes matter from a nearby star. The discovery provides new insight into the behaviours of some of the most extreme objects in the universe.

Low-mass X-ray binaries (LMXBs) are systems containing a neutron star or black hole. They are fuelled by material ripped from a neighbouring star, a process known as accretion. Most accretion occurs during violent eruptions where the systems brighten dramatically. At the same time, some of the material that spirals in is propelled back into space in the form of disc winds and jets.

The most common signs of outflowing material from astronomical objects are associated with "warm" gas. Despite this, only winds of "hot" or "cold" gas have been observed in transient X-ray binaries, until now.

In this new study, a team of researchers from eleven countries, led by the University of Southampton, studied the recent eruption of the X-ray binary known as Swift J1858. They used a combination of telescopes, including NASA's Hubble Space Telescope (HST), the European Space Agency's XMM-Newton satellite, the European Southern Observatory Organisation's Very Large Telescope (VLT) and the Spanish Gran Telescopio Canarias (GTC).

The results, published in the journal Nature, showed persistent signatures of a warm wind at ultraviolet wavelengths occurring at the same time as signatures of a cold wind at optical wavelengths. This is the first time that winds from such a system have been seen across different bands of the electromagnetic spectrum.

Lead author Dr Noel Castro Segura, of the University of Southampton said: "Eruptions like this are rare, and each of them is unique. Normally they are heavily obscured by interstellar dust, which makes observing them really difficult. Swift J1858 was special, because even though it is located on the other side of our galaxy, the obscuration was small enough to allow for a full multiwavelength study."

"Only one other system -- the black hole X-ray binary, V404 Cyg -- has shown similar properties. However, our attempt to perform the same experiment on that system was unsuccessful, because the eruption ended before we could get the ground-based and space-based telescopes to observe it simultaneously," co-Author Dr Hernández Santisteban from University of St Andrews said.

Swift J1858 is a newly discovered X-ray transient event that displays extreme variability across the electromagnetic spectrum, which presented a rare opportunity.

"All the astronomers in the field were incredibly excited, to the point that we combined our efforts to cover the full spectrum, from radio to X-ray using state-of-art observatories on Earth and in space," Dr Castro Segura continued.

Co-author Nathalie Degenaar, from the University of Amsterdam added, "Neutron stars have an immensely strong gravitational pull that allows them to gobble up gas from other stars. The stellar cannibals are, however, messy eaters and much of the gas that neutron stars pull towards them is not consumed, but flung into space at high speed. This behaviour has a large impact both on the neutron star itself, and on its immediate surroundings. In this paper we report on a new discovery that provides key information about the messy eating patterns of these cosmic cookie monsters."

"This time we had cosmic luck on our side, as we were able to co-ordinate ten telescopes and point them towards the J1858, all while it was fully active. This allows us to obtain much more information, since we can use different techniques at different wavelengths," Dr Hernández Santisteban said.

Dr Degenaar added, "designing such an ambitious observing campaign -- built around the best telescopes on Earth and in space -- was a huge challenge. So, it is incredibly exciting that all this work has paid off and allowed us to make a key discovery that would not have been possible otherwise."

As well as discovering the different types of winds, the team were able to study the temporal evolution of the gas that flows out. They found that the warm wind was not affected by the strong variations in the brightness of the system. The absence of such a response had previously been an unconfirmed theoretical prediction based on sophisticated simulations.

"In this research we combined the unique capabilities of the HST with the best ground-based telescopes, such as the VLT and GTC, to obtain a complete picture of the dynamics of the gas in the system, from the near-infrared to ultraviolet wavelengths. This allowed us to unveil for first time the true nature of these powerful outflows," Dr Castro Segura said.

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Dark energy: Neutron stars will tell us if it's only an illusion

A huge amount of mysterious dark energy is necessary to explain cosmological phenomena, such as the accelerated expansion of the Universe, with Einstein's theory. But what if dark energy was just an illusion and general relativity itself had to be modified? A new SISSA study, published in Physical Review Letters, offers a new approach to answer this question. Thanks to huge computational and mathematical effort, scientists produced the first simulation ever of merging binary neutron stars in theories beyond general relativity that reproduce a dark- energy like behavior on cosmological scales. This allows the comparison of Einstein's theory and modified versions of it, and, with sufficiently accurate data, may solve the dark energy mystery.

For about 100 years now, general relativity has been very successful at describing gravity on a variety of regimes, passing all experimental tests on Earth and the solar system. However, to explain cosmological observations such as the observed accelerated expansion of the Universe, we need to introduce dark components, such as dark matter and dark energy, which still remain a mystery.

Enrico Barausse, astrophysicist at SISSA (Scuola Internazionale Superiore di Studi Avanzati) and principal investigator of the ERC grant GRAMS (GRavity from Astrophysical to Microscopic Scales) questions whether dark energy is real or, instead, it may be interpreted as a breakdown of our understanding of gravity. "The existence of dark energy could be just an illusion," he says, "the accelerated expansion of the Universe might be caused by some yet unknown modifications of general relativity, a sort of 'dark gravity'."

The merger of neutron stars offers a unique situation to test this hypothesis because gravity around them is pushed to the extreme. "Neutron stars are the densest stars that exist, typically only 10 kilometers in radius, but with a mass between one or two times the mass of our Sun," explains the scientist. "This makes gravity and the spacetime around them extreme, allowing for abundant production of gravitational waves when two of them collide. We can use the data acquired during such events to study the workings of gravity and test Einstein's theory in a new window."

In this study, published in Physical Review Letters, SISSA scientists in collaboration with physicists from Universitat de les Illes Balears in Palma de Mallorca, produced the first simulation of merging binary neutron stars in theories of modified gravity relevant for cosmology: "This type of simulations is extremely challenging," clarifies Miguel Bezares, first author of the paper, "because of the highly non-linear nature of the problem. It requires a huge computational effort -months of run in supercomputers -- that was made possible also by the agreement between SISSA and CINECA consortium as well as novel mathematical formulations that we developed. These represented major roadblocks for many years till our first simulation."

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Higher education and language skills may help ward off dementia

New research has found that people with mild cognitive impairment may not inevitably develop dementia and, in fact, having higher education and advanced language skills more than doubles their chances of returning to normal.

The study, led by researchers at the University of Waterloo, may reassure those with mild cognitive impairment as it contradicts a common assumption that the condition is simply an early stage of dementia. People with mild cognitive impairment show signs of cognitive decline, but not enough to prevent them from performing typical daily tasks. They have been considered at higher risk of progressing to the more severe cognitive decline seen in dementia.

"Possessing high cognitive reserve -- based on education, high academic grades, and written language skills -- may predict what happens years after someone receives a diagnosis of mild cognitive impairment," said Suzanne Tyas, a professor in the School of Public Health Sciences at Waterloo and lead author. "Even after considering age and genetics -- established risk factors for dementia -- we found that higher levels of education more than doubled the chances that people with mild cognitive impairment would return to normal cognition instead of progressing to dementia."

The study also found that language skills, whether reflected in high grades in English in school or in strong writing that was grammatically complex and full of ideas, were also protective.

The researchers discovered that almost one-third of 472 women diagnosed with mild cognitive impairment reverted to normal cognition at least once over an average of eight-and-a-half years following their diagnosis, with more than 80 per cent of them never developing dementia.

Almost another third of the total number progressed to dementia without ever reverting to normal cognition, while three per cent stayed in the mild cognitive impairment stage, and 36 per cent died. None of the participants reverted from dementia to mild cognitive impairment.

The researchers also highlighted that reverse transitions are much more common than progressing to dementia in relatively younger individuals who didn't carry a certain genetic risk factor and had high levels of education and language skills.

"We can't do much about age and genetics, so it's encouraging that our findings show that there are other ways to reduce the risk of dementia, such as building cognitive reserve through education and language skills earlier in life," Tyas said.

The study's findings have implications for treatment and research in people with mild cognitive impairment.

"If individuals with higher cognitive reserve are more likely to improve even without treatment, then this needs to be taken into consideration when recruiting participants for clinical trials of prospective treatments and when interpreting the results of these trials," Tyas said, adding there's no cure for most causes of dementia, so prevention is key.

For the analysis, researchers used complex modelling with data drawn from a longitudinal study called the Nun Study, which looked at older, highly educated religious sisters. The participants were mostly homogeneous, with similar socioeconomic status and marital and reproductive history, strengthening the conclusions of this work.

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New method to produce chemically modified mRNA developed

In a recent study, the research group at the University of Cologne’s Institute of Organic Chemistry led by Professor Dr Stephanie Kath-Schorr describes a novel method for the enzymatic production of synthetic messenger RNA (mRNA). While natural base modifications of mRNA are already being used – for example by BioNTech/Pfizer for the production of their coronavirus vaccine – this newly developed mRNA additionally contains site-specifically introduced, non-natural nucleotides. Nucleotides are molecules that function as the basic building blocks of RNA. This new approach using non-natural nucleotides allows the scientists to study how mRNA is introduced into cells and to observe how the newly introduced information spreads at the cellular level. This in turn promises better therapeutic applications in the long run. The article ‘Stronger together for in cell translation: natural and unnatural base modified mRNA’ has appeared in Chemical Science.

Previous methods did not allow for the production of mRNAs with chemically modified building blocks at specific positions because mRNAs are produced enzymatically due to their length of several thousands of building blocks. In the new method, the researchers use a so-called ‘expanded genetic alphabet’ during the enzymatic transcription of DNA to RNA. Where normally two base pairs are responsible for transcription, the team introduced a third base pair. This allowed them to introduce unnatural RNA nucleotides into specific mRNA segments, to modify protein production, and to study cellular application in detail.

‘We investigated how stable this chemically modified mRNA is in cells, whether the artificially produced mRNA can be used in cells as a template for efficient protein production, and what influence the chemical modifications have on protein production,’ said Kath-Schorr. The results show that the new method is very powerful for monitoring the introduction of mRNA into cells, and for monitoring and influencing its spread at the cellular level as well as the efficiency of information transcription. This opens up new possibilities to develop efficient mRNA therapies – not only as vaccines, but also in cancer therapy.

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Vaccine and antibody treatment effectiveness blunted by all three Omicron subvariants

Only one currently authorized antibody treatment retains its activity against all Omicron subvariants, according to new research by scientists at Columbia University and the University of Hong Kong. The study also shows that the effectiveness of mRNA vaccines is reduced against all three subvariants of Omicron.

The findings were published in Nature on March 2 by David D. Ho, MD, director of the Aaron Diamond AIDS Research Center and the Clyde'56 and Helen Wu Professor of Medicine at Columbia University Vagelos College of Physicians and Surgeons.

Omicron is a highly transmissible variant of SARS-CoV-2 that has caused the biggest surge in COVID cases so far in many countries. Researchers have identified three subvariants of Omicron that share 21 mutations in the spike protein, and named them BA.1, BA.1.1 and BA.2.

When Omicron was first identified in November 2021, the dominant variant was BA.1. Since December, BA.1 cases have declined, while BA1.1 cases have risen and now make up around 40% of all Omicron cases sequenced globally. The BA.2 subvariant currently represents only 10% of all Omicron cases globally but is increasing in prevalence.

In laboratory experiments, Ho and his team studied the ability of 19 monoclonal antibodies and the sera from individuals immunized with one of two available mRNA vaccines to neutralize the three known subvariants of Omicron.

Consistent with their previous study on the BA.1 variant, the researchers observed a similar loss of neutralization activity against BA.1.1 and BA.2 in blood samples from individuals who had received two mRNA shots. However, the decline in neutralization was less prominent in blood samples from individuals who had received three mRNA shots, reinforcing the importance of booster shots for sustaining immunity.

In neutralization experiments, all three variants exhibited a strong resistance to most of the monoclonal antibodies tested. Of 19 antibodies, 17 were ineffective against the BA.2 subvariant. The researchers found that bebtelovimab, the latest monoclonal antibody to receive FDA Emergency Use Authorization, is the only currently available antibody therapy that can adequately treat all three Omicron subvariants.

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A solar illusion: Coronal loops may not be what they seem

Many coronal loops -- ropey strands of plasma that scientists have long thought existed in the Sun's atmosphere -- may actually be optical illusions, according to a new paper that challenges prevailing assumptions of what we know, and don't know, about the Sun.

The research, led by the National Center for Atmospheric Research (NCAR) and published in The Astrophysical Journal, relied on a cutting-edge, realistic 3D simulation of the solar corona. The simulation, carried out at NCAR several years ago, allowed the scientists to slice the corona in distinct sections in an effort to isolate individual coronal loops.

What they found is that many of the loops weren't loops at all.

While the research team was able to pinpoint some of the coronal loops they were looking for, they also found that in many cases what appear to be loops in images taken of the Sun may actually be wrinkles of bright plasma in the solar atmosphere. As sheets of bright plasma fold over themselves, the folds look like bright thin lines, mimicking the look of distinct and self-contained strands of plasma.

The findings, which the research team is calling the "coronal veil" hypothesis, have significant implications for our understanding of the Sun, since the presumed coronal loops have been used for decades as a way to infer information about density, temperature, and other physical characteristics of the solar atmosphere.

"I have spent my entire career studying coronal loops," said NCAR scientist Anna Malanushenko, who led the study. "I was excited that this simulation would give me the opportunity to study them in more detail. I never expected this. When I saw the results, my mind exploded. This is an entirely new paradigm of understanding the Sun's atmosphere."

The research was funded by NASA and included collaborators from NCAR's High Altitude Observatory, Lockheed Martin Solar and Astrophysics Laboratory, the Southwest Research Institute, and NASA Goddard. NCAR is sponsored by the National Science Foundation.

Challenging intuition

What appears to be coronal loops can be seen in images taken of the Sun in extreme ultraviolet light. The assumption that they exist is a natural one for scientists because it fits our most basic understanding of magnetism.

Most schoolchildren have at some point seen what happens when iron filings are sprinkled near a bar magnet. The filings orient themselves along magnetic field lines that loop from one pole of the bar magnet to the other. These curving lines spread out, becoming weaker and less dense, the further they are from the magnet.

The apparent coronal loops in images of the Sun look strikingly similar, and since there is a significant magnetic field in the Sun, the existence of magnetic field lines that could trap a rope of plasma between them and create loops seems like an obvious explanation. And in fact, the new study confirms that such loops likely exist.

However, the coronal loops seen on the Sun have never behaved exactly as they should, based on our understanding of magnets. For example, scientists would expect the magnetic field lines on the Sun to spread apart, just as in the iron filings experiment, as you move higher in the corona. If this happened, the plasma trapped between the field lines would also spread out between the boundaries, creating thicker, less bright loops. But images of the Sun do not show this phenomenon. Instead, the loops further out still appear thin and bright.

The possibility that these loops are instead wrinkles in a coronal veil helps explain this and other discrepancies with our expectations of the loops -- but it also asks new questions. For example, what determines the shape and thickness of the folds? And how many of the apparent loops in images of the Sun are actually real strands, and how many are optical illusions?

"This study reminds us as scientists that we must always question our assumptions and that sometimes our intuition can work against us," Malanushenko said.

Innovative model offers new view of the Sun

The discovery that coronal loops may be illusions was made possible thanks to an extremely detailed simulation of the solar corona produced by MURaM, a radiative magnetohydrodynamic model that was extended to model the solar corona in an effort led by NCAR.

The simulation was groundbreaking when it was first produced because it was able to simultaneously model what was happening in multiple regions of the Sun, from the upper part of the convective zone -- about 10,000 kilometers below the Sun's surface -- through the solar surface and beyond, up to nearly 40,000 kilometers into the solar corona. These varied regions of the Sun cover a vast range of physical conditions, including differences in density and pressure, and so scientists had not previously figured out a way to mathematically represent these regions in a unified simulation.

Among other results, the new simulation was able to capture the entire life cycle of a solar flare for the first time, from the build up of energy below the solar surface to the emergence of flare at the surface, and finally to the explosive release of energy.

The model also produced 3-dimensional data sets that contain the structure of the magnetic field and plasma, which can be used to generate "synthetic" observations. Because the solar corona is optically thin -- meaning it's relatively easy to see through it -- structures in the corona overlap one another in images of the Sun. This makes it difficult to tell whether a "loop" that is overlapping other loops is in front or behind. It's also difficult to tell whether the loop itself has a compact cross section, like a garden hose, or resembles a long ribbon viewed edge on. It's also possible that what appears to be a thin strand may be an optical artifact caused by a fold in a sheet of bright plasma.

The cubes of data produced by MURaM provide scientists the opportunity to dissect the solar atmosphere and study the overlapping structures separately, something that is not possible with the observatories and instruments we currently have.

While the MURaM simulation is one of the most realistic ever created of the solar corona, it's still just a model. Understanding how many coronal loops are actually optical illusions will require carefully designed observational methods that probe the corona and new data analysis techniques.

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'Closest black hole' system found to contain no black hole

In 2020 a team led by European Southern Observatory (ESO) astronomers reported the closest black hole to Earth, located just 1000 light-years away in the HR 6819 system. But the results of their study were contested by other researchers, including by an international team based at KU Leuven, Belgium. In a paper published today, these two teams have united to report that there is in fact no black hole in HR 6819, which is instead a "vampire" two-star system in a rare and short-lived stage of its evolution.

The original study on HR 6819 received significant attention from both the press and scientists. Thomas Rivinius, a Chile-based ESO astronomer and lead author on that paper, was not surprised by the astronomy community's reception to their discovery of the black hole. "Not only is it normal, but it should be that results are scrutinised," he says, "and a result that makes the headlines even more so."

Rivinius and his colleagues were convinced that the best explanation for the data they had, obtained with the MPG/ESO 2.2-metre telescope, was that HR 6819 was a triple system, with one star orbiting a black hole every 40 days and a second star in a much wider orbit. But a study led by Julia Bodensteiner, then a PhD student at KU Leuven, Belgium, proposed a different explanation for the same data: HR 6819 could also be a system with only two stars on a 40-day orbit and no black hole at all. This alternative scenario would require one of the stars to be "stripped," meaning that, at an earlier time, it had lost a large fraction of its mass to the other star.

"We had reached the limit of the existing data, so we had to turn to a different observational strategy to decide between the two scenarios proposed by the two teams," says KU Leuven researcher Abigail Frost, who led the new study published today in Astronomy & Astrophysics.

To solve the mystery, the two teams worked together to obtain new, sharper data of HR 6819 using ESO's Very Large Telescope (VLT) and Very Large Telescope Interferometer (VLTI). "The VLTI was the only facility that would give us the decisive data we needed to distinguish between the two explanations," says Dietrich Baade, author on both the original HR 6819 study and the new Astronomy & Astrophysics paper. Since it made no sense to ask for the same observation twice, the two teams joined forces, which allowed them to pool their resources and knowledge to find the true nature of this system.

"The scenarios we were looking for were rather clear, very different and easily distinguishable with the right instrument," says Rivinius. "We agreed that there were two sources of light in the system, so the question was whether they orbit each other closely, as in the stripped-star scenario, or are far apart from each other, as in the black hole scenario."

To distinguish between the two proposals, the astronomers used both the VLTI's GRAVITY instrument and the Multi Unit Spectroscopic Explorer (MUSE) instrument on ESO's VLT.

"MUSE confirmed that there was no bright companion in a wider orbit, while GRAVITY's high spatial resolution was able to resolve two bright sources separated by only one-third of the distance between the Earth and the Sun," says Frost. "These data proved to be the final piece of the puzzle, and allowed us to conclude that HR 6819 is a binary system with no black hole."

"Our best interpretation so far is that we caught this binary system in a moment shortly after one of the stars had sucked the atmosphere off its companion star. This is a common phenomenon in close binary systems, sometimes referred to as "stellar vampirism" in the press," explains Bodensteiner, now a fellow at ESO in Germany and an author on the new study. "While the donor star was stripped of some of its material, the recipient star began to spin more rapidly."

"Catching such a post-interaction phase is extremely difficult as it is so short," adds Frost. "This makes our findings for HR 6819 very exciting, as it presents a perfect candidate to study how this vampirism affects the evolution of massive stars, and in turn the formation of their associated phenomena including gravitational waves and violent supernova explosions."

The newly formed Leuven-ESO joint team now plans to monitor HR 6819 more closely using the VLTI's GRAVITY instrument. The researchers will conduct a joint study of the system over time, to better understand its evolution, constrain its properties, and use that knowledge to learn more about other binary systems.

As for the search for black holes, the team remains optimistic. "Stellar-mass black holes remain very elusive owing to their nature," says Rivinius. "But order-of-magnitude estimates suggest there are tens to hundreds of millions of black holes in the Milky Way alone," Baade adds. It is just a matter of time until astronomers discover them.

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Why exercise gets harder the less you do

Doing less exercise could deactivate a vital protein in the body, causing further inactivity and making exercise more difficult, new research suggests.

University of Leeds scientists have discovered that deactivating the Piezo1 protein, a blood flow sensor, reduces the density of capillaries carrying blood to the muscles.

This restricted blood flow means activity becomes more difficult and can lead to a reduction in how much exercise is possible, the team found.

They say the results help to explain the biology of why exercise becomes harder the less you do.

The paper, Endothelial Piezo1 sustains muscle capillary density and contributes to physical activity, is published today in Journal of Clinical Investigation.

The experiments were carried out in mice, but the Piezo1 protein is found in humans, suggesting the same results could occur.

Lead author Fiona Bartoli, a Postdoctoral Researcher in the University of Leeds' School of Medicine, said: "Exercise protects against cardiovascular disease, diabetes, depression and cancer. Unfortunately, many people fail to exercise enough, for reasons such as injury and computer usage. This puts people at more risk of disease. The less people exercise, the less fit they become, often leading to a downward spiral.

"Although many responses to exercise are known, how the benefits of exercise are initially triggered at a molecular level is mysterious. Our study highlights the crucial link between physical activity and physical performance made at this level by Piezo1. Keeping our Piezo1s active by exercising may be crucial in our physical performance and health."

During the experiment, scientists compared two groups of mice -- a control group, and a group whose Piezo1 levels had been disrupted for 10 weeks. Walking, climbing and running wheel activity was observed, with the Piezo1 mice showing a striking reduction in activity levels. This suggests an important role for Piezo1 in sustaining normal physical activity.

The researchers considered whether the Piezo1 mice were less interested in exercise, but they found no differences in the amount or duration of activity between the two groups. Instead, there were fewer running wheel revolutions per exercise session, and slower running speed, suggesting a lowered ability to exercise, without a lesser desire.

Supervising author Professor David Beech, in the University of Leeds' School of Medicine, said: "Our work sheds new light on how Piezo1's role in blood vessels is connected to physical activity. A lot was already known about its role in blood vessel development, but far less was known about its contribution to vessel maintenance in adults.

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Tyrannosaurus remains hint at three possible distinct species

A new analysis of Tyrannosaurus skeletal remains reveals physical differences in the femur, other bones and dental structures across specimens that could suggest Tyrannosaurus rex specimens need to be re-categorised into three distinct groups or species, reports a study published in Evolutionary Biology.

Tyrannosaurus rex is the only recognised species of the group of dinosaurs, or genus, Tyrannosaurus to date. Previous research has acknowledged variation across Tyrannosaurus skeletal remains in the femur (thighbone) and specimens with either one or two slender incisor teeth on each side of front ends of the jaw.

Gregory Paul and colleagues analysed the bones and dental remains of 37 Tyrannosaurus specimens. The authors compared the robustness of the femur in 24 of the specimens, a measure calculated from the length and circumference that gives an indication of the strength of the bone. They also measured the diameter of the base of teeth or space in the gums to assess if specimens had one or two slender incisiform teeth.

The authors observed that the femur varied across specimens, some with more robust femurs and others with more gracile femurs. The authors found there were two times more robust femurs than gracile ones across specimens, which suggests that this is not a difference caused by sex, which would likely result in a more even split. The authors also suggest that the variation in femurs is not related to growth of the specimen as robust femurs were found in some juvenile specimens two thirds the size of an adult and gracile femurs were found in some specimens that were full adult size.

Dental structure also varied across specimens, although those with both femur measurements and dental remains was low (12 specimens). Specimens with one incisor tooth were correlated with often having higher femur gracility.

Of the Tyrannosaurus specimens, 28 could be identified in distinct layers of sediment (stratigraphy) at the Lancian upper Masstrichtian formations in North America (estimated to be from between 67.5 to 66 million years ago). The authors compared Tyrannosaurus specimens with other theropod species found in lower layers of sediment.

Only robust Tyrannosaurus femurs were found in the lower layer of sediment (six femurs). The variation of femur robustness in the lower layer was not different to that of other theropod species, which indicates that likely only one species of Tyrannosaurus existed at this point. Only one gracile Tyrannosaurus femur was identified in the middle layer with five other gracile femurs in the upper layer, alongside other robust femurs. The variation in Tyrannosaurus femur robustness in the top layer of the sediments was higher than what was observed in some earlier theropod specimens. This suggests that the Tyrannosaurus specimens found at higher layers of sediment physically developed into more distinct forms compared to specimens from lower layers, and other dinosaur species.

Gregory Paul, lead author, said: "We found that the changes in Tyrannosaurus femurs are likely not related to the sex or age of the specimen. We propose that the changes in the femur may have evolved over time from a common ancestor who displayed more robust femurs to become more gracile in later species. The differences in femur robustness across layers of sediment may be considered distinct enough that the specimens could potentially be considered separate species."

The authors nominate two potential new species of Tyrannosaurus based on their analysis. The first, Tyrannosaurus imperator (tyrant lizard emperor), relates to specimens found at the lower and middle layers of sediment, characterised with more robust femurs and usually two incisor teeth. The authors argue these features have been retained from earlier ancestors (tyrannosaurids). The second, Tyrannosaurus regina (tyrant lizard queen), is linked to specimens from the upper and possibly middle layers of sediment, characterised with slenderer femurs and one incisor tooth. The recognised species Tyrannosaurus rex (tyrant lizard king) was identified in the upper and possibly middle layer of sediment with specimens classed as retaining more robust femurs while having only one incisor tooth. Some specimens could not be identified based on their remains so were not assigned to a species.

The authors acknowledge that they cannot rule out that the observed variation is due to extreme individual differences, or atypical sexual dimorphism, rather than separate groups, and they also caution that the location within sediment layers is not known for some specimens. The authors discuss the difficulties of assigning fossil vertebrates to a potential new species.

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What’s happening in the depths of distant worlds?

The physics and chemistry that take place deep inside our planet are fundamental to the existence of life as we know it. But what forces are at work in the interiors of distant worlds, and how do these conditions affect their potential for habitability?

New work led by Carnegie's Earth and Planets Laboratory uses lab-based mimicry to reveal a new crystal structure that has major implications for our understanding of the interiors of large, rocky exoplanets. Their findings are published by Proceedings of the National Academy of Sciences.

"The interior dynamics of our planet are crucial for maintaining a surface environment where life can thrive -- driving the geodynamo that creates our magnetic field and shaping the composition of our atmosphere," explained Carnegie's Rajkrishna Dutta, the lead author. "The conditions found in the depths of large, rocky exoplanets such as super-Earths would be even more extreme."

Silicate minerals make up most of the Earth's mantle and are thought to be a major component of the interiors of other rocky planets, as well, based on calculations of their densities. On Earth, the structural changes induced in silicates under high pressure and temperature conditions define key boundaries in Earth's deep interior, like that between the upper and lower mantle.

The research team -- which included Carnegie's Sally June Tracy, Ron Cohen, Francesca Miozzi, Kai Luo, and Jing Yang, as well as Pamela Burnley of the University of Nevada Las Vegas, Dean Smith and Yue Meng of Argonne National Laboratory, Stella Chariton and Vitali Prakapenka of the University of Chicago, and Thomas Duffy of Princeton University -- was interested in probing the emergence and behavior of new forms of silicate under conditions mimicking those found in distant worlds.

"For decades, Carnegie researchers have been leaders at recreating the conditions of planetary interiors by putting small samples of material under immense pressures and high temperatures," said Duffy.

But there are limitations on scientists' ability to recreate the conditions of exoplanetary interiors in the lab. Theoretical modeling has indicated that new phases of silicate emerge under the pressures expected to be found in the mantles of rocky exoplanets that are at least four times more massive than Earth. But this transition has not yet been observed.

However, germanium is a good stand-in for silicon. The two elements form similar crystalline structures, but germanium induces transitions between chemical phases at lower temperatures and pressures, which are more manageable to create in laboratory experiments.

Working with magnesium germanate, Mg2GeO4, analogous to one of the mantle's most abundant silicate minerals, the team was able to glean information about the potential mineralogy of super-Earths and other large, rocky exoplanets.

Under about 2 million times normal atmospheric pressure a new phase emerged with a distinct crystalline structure that involves one germanium bonded with eight oxygens.

"The most interesting thing to me is that magnesium and germanium, two very different elements, substitute for each other in the structure," Cohen said.

Under ambient conditions, most silicates and germanates are organized in what's called a tetrahedral structure, one central silicon or germanium bonded with four other atoms. However, under extreme conditions, this can change.

"The discovery that under extreme pressures, silicates could take on a structure oriented around six bonds, rather than four, was a total game-changer in terms of scientists' understanding of deep Earth dynamics," Tracy explained. "The discovery of an eightfold orientation could have similarly revolutionary implications for how we think about the dynamics of exoplanet interiors."

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Noble false widow spider captures bats in the attic

Scientists from the Ryan Institute in NUI Galway have published the first record of a Noble False Widow spider feeding on a protected species of Pipistrelle bats in the UK.

The new study, published today in the international journal Ecosphere,demonstrates that False Widow spiders continue to impact native species.

It is the first time a member of this family of spiders, called Theridiidae, has been recorded preying on a bat anywhere in the world, or any vertebrate in Britain.

It is also the first time for any species of false widow spider to be recorded preying on mammals.

The extraordinary discovery was made by wildlife artist Ben Waddams at his home in north Shropshire, England. On two consecutive days, bats living in the attic were found entangled on the spider's web below the entrance to the roost.

The first bat, a young pup, was completely immobilised with its limbs pinned tightly to the torso with silk. It was slightly shrivelled and discoloured from the spider feeding off the remains.

A second, much larger adult bat, was also captured and entangled in the web but as it was still alive, the bat was rescued from the web and released.

In Britain, the Pipistrelle bats are protected under the Wildlife and Countryside Act, 1981, and the Conservation of Habitats and Species Regulations 2017.

The rather grisly event is not as uncommon as people might expect, three years ago the Noble False Widow spider was reported feeding on a protected species of native lizard in Ireland.

Originating from Madeira and the Canary Islands, the Noble False Widow spider Steatoda nobilis has the potential to become one of the world's most invasive species of spider.

It was first reported in southern England in 1879 and has increased its range and population density in recent decades, spreading northwards towards Scotland and westward through Wales and Ireland. In that time the species has also spread globally from across Europe, East Asia, North America, and South America.

The species is known for its medical significance, having the ability to cause a range of mild to severe symptoms in people who are bitten, but little is known about its impact on native species.

Over the past five years, the team led by Dr Michel Dugon in NUI Galway's Ryan Institute, have been studying a wide range of characteristics specific to the species including its venom, symptoms after envenomation, ecology and behaviour.

Dr Michel Dugon, Head of the Venom Systems Lab, Ryan Institute, NUI Galway and senior author of the study, said: "We have been working on the Noble False Widow for the past five years, and have learnt a great deal about this species -- yet, we are still surprised by its ability to adapt to new environments and make the most of the resources available. It is a truly remarkable species."

Dr John Dunbar, Irish Research Council Post-Doctoral fellow, Venom Systems Lab, Ryan Institute, NUI Galway and lead author of the study, said: "In more exotic parts of the world, scientists have been documenting such predation events by spiders on small vertebrates for many years, but we are only beginning to realise just how common these events occur. Now that this alien species has become well established in Ireland and Britain, we are witnessing such fascinating events on our very own doorstep.

"Even other, much smaller, species of false widows are known to capture and feed on snakes and lizards. This study presents yet another example of the invasive impact by the Noble false widow spider on native species. We know they are much more competitive than native spiders, and this further confirms their impact on prey species."

They possess a fast-acting neurotoxic venom with a very similar composition to true black widows that can cause neuromuscular paralysis in terrestrial vertebrates which allows them to occasionally feed on small reptiles and mammals.

Aiste Vitkauskaite, researcher at the Venom Systems Lab, Ryan Institute, NUI Galway, said: "False widow spiders, just as their close relatives' black widow spiders, have extraordinary prey capture techniques and remarkably potent venom which allows them to capture small vertebrate prey many times larger than the spider itself with surprising ease.

"In the last three years alone, we have observed two occasions of the alien Noble False Widow capturing and feeding on protected species of vertebrate animals in Ireland and Britain. As the Noble False Widow continues to expand its range and increase populations across Ireland and Britain, we should expect to observe similar predation events on small vertebrate animals by this spider, including protected species."

Read more at Science Daily

Climate change: A threat to human wellbeing and health of the planet

Human-induced climate change is causing dangerous and widespread disruption in nature and affecting the lives of billions of people around the world, despite efforts to reduce the risks. People and ecosystems least able to cope are being hardest hit, said scientists in the latest Intergovernmental Panel on Climate Change (IPCC) report, released today.

"This report is a dire warning about the consequences of inaction," said Hoesung Lee, Chair of the IPCC. "It shows that climate change is a grave and mounting threat to our wellbeing and a healthy planet. Our actions today will shape how people adapt and nature responds to increasing climate risks."

The world faces unavoidable multiple climate hazards over the next two decades with global warming of 1.5°C (2.7°F). Even temporarily exceeding this warming level will result in additional severe impacts, some of which will be irreversible. Risks for society will increase, including to infrastructure and low-lying coastal settlements.

The Summary for Policymakers of the IPCC Working Group II report, Climate Change 2022: Impacts, Adaptation and Vulnerability was approved on Sunday, February 27 2022, by 195 member governments of the IPCC, through a virtual approval session that was held over two weeks starting on February 14.

Urgent action required to deal with increasing risks

Increased heatwaves, droughts and floods are already exceeding plants' and animals' tolerance thresholds, driving mass mortalities in species such as trees and corals. These weather extremes are occurring simultaneously, causing cascading impacts that are increasingly difficult to manage. They have exposed millions of people to acute food and water insecurity, especially in Africa, Asia, Central and South America, on Small Islands and in the Arctic.

To avoid mounting loss of life, biodiversity and infrastructure, ambitious, accelerated action is required to adapt to climate change, at the same time as making rapid, deep cuts in greenhouse gas emissions. So far, progress on adaptation is uneven and there are increasing gaps between action taken and what is needed to deal with the increasing risks, the new report finds. These gaps are largest among lower-income populations.

The Working Group II report is the second instalment of the IPCC's Sixth Assessment Report (AR6), which will be completed this year.

"This report recognizes the interdependence of climate, biodiversity and people and integrates natural, social and economic sciences more strongly than earlier IPCC assessments," said Hoesung Lee. "It emphasizes the urgency of immediate and more ambitious action to address climate risks. Half measures are no longer an option."

Safeguarding and strengthening nature is key to securing a liveable future

There are options to adapt to a changing climate. This report provides new insights into nature's potential not only to reduce climate risks but also to improve people's lives.

"Healthy ecosystems are more resilient to climate change and provide life-critical services such as food and clean water," said IPCC Working Group II Co-Chair Hans-Otto Pörtner. "By restoring degraded ecosystems and effectively and equitably conserving 30 to 50 per cent of Earth's land, freshwater and ocean habitats, society can benefit from nature's capacity to absorb and store carbon, and we can accelerate progress towards sustainable development, but adequate finance and political support are essential."

Scientists point out that climate change interacts with global trends such as unsustainable use of natural resources, growing urbanization, social inequalities, losses and damages from extreme events and a pandemic, jeopardizing future development.

"Our assessment clearly shows that tackling all these different challenges involves everyone -- governments, the private sector, civil society -- working together to prioritize risk reduction, as well as equity and justice, in decision-making and investment," said IPCC Working Group II Co-Chair Debra Roberts.

"In this way, different interests, values and world views can be reconciled. By bringing together scientific and technological know-how as well as Indigenous and local knowledge, solutions will be more effective. Failure to achieve climate resilient and sustainable development will result in a sub-optimal future for people and nature."

Cities: Hotspots of impacts and risks, but also a crucial part of the solution

This report provides a detailed assessment of climate change impacts, risks and adaptation in cities, where more than half the world's population lives. People's health, lives and livelihoods, as well as property and critical infrastructure, including energy and transportation systems, are being increasingly adversely affected by hazards from heatwaves, storms, drought and flooding as well as slow-onset changes, including sea level rise.

"Together, growing urbanization and climate change create complex risks, especially for those cities that already experience poorly planned urban growth, high levels of poverty and unemployment, and a lack of basic services," Debra Roberts said.

"But cities also provide opportunities for climate action -- green buildings, reliable supplies of clean water and renewable energy, and sustainable transport systems that connect urban and rural areas can all lead to a more inclusive, fairer society."

There is increasing evidence of adaptation that has caused unintended consequences, for example destroying nature, putting peoples' lives at risk or increasing greenhouse gas emissions. This can be avoided by involving everyone in planning, attention to equity and justice, and drawing on Indigenous and local knowledge.

A narrowing window for action

Climate change is a global challenge that requires local solutions and that's why the Working Group II contribution to the IPCC's Sixth Assessment Report (AR6) provides extensive regional information to enable Climate Resilient Development.

The report clearly states Climate Resilient Development is already challenging at current warming levels. It will become more limited if global warming exceeds 1.5°C (2.7°F). In some regions it will be impossible if global warming exceeds 2°C (3.6°F). This key finding underlines the urgency for climate action, focusing on equity and justice. Adequate funding, technology transfer, political commitment and partnership lead to more effective climate change adaptation and emissions reductions.

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Scaling laws in enzymes may help predict life ‘as we don’t know it'

The only references we have for "life" are the forms we know on Earth. Astrobiologists suspect that the search for alien life, and even for the origins of life on Earth, may require a broader scope. A NASA-funded team of researchers is developing tools to predict the features of life as we don't know it. In a new study published in the Proceedings of the National Academy of Sciences, the team identifies universal patterns in the chemistry of life that do not appear to depend on specific molecules.

"We want to have new tools for identifying and even predicting features of life as we don't know it," says Santa Fe Institute External Professor Sara Imari Walker (Arizona State University), a co-author on the paper. "To do so, we are aiming to identify the universal laws that should apply to any biochemical system. This includes developing quantitative theory for the origins of life, and using theory and statistics to guide our search for life on other planets."

On Earth, life emerges from the interplay of hundreds of chemical compounds and reactions. Some of these compounds and reactions are found universally across Earth's organisms. Using the Integrated Microbial Genomes and Microbiomes database, the team investigated the enzymes -- the functional drivers of biochemistry -- found in bacteria, archaea, and eukarya to reveal a new kind of biochemical universality.

Enzymes can be categorized into a taxonomy of broad functional classes -- groups designated by what they do, from using water molecules to break chemical bonds (hydrolases) to rearranging molecular structures (isomerases) to joining large molecules together (ligases). The team compared how the abundance of enzymes in each of these functional categories changed in relation to the overall abundance of enzymes in an organism. They discovered various scaling laws -- almost algorithmic relationships -- between the number of enzymes in different enzyme classes and the size of an organism's genome. They also found that these laws don't depend on the particularenzymes in those classes.

"Here we find that you get these scaling relationships without needing to conserve exact membership. You need a certain number of transferases, but not particular transferases," says SFI Professor Chris Kempes, a co-author on the paper. "There are a lot 'synonyms,' and those synonyms scale in systematic ways."

On Earth, organisms use DNA and, through RNA, create proteins. But will the macromolecules of DNA, RNA, and proteins help us identify life across the universe, understand the origins of life on Earth, or develop synthetic biology? "As a team, we think that's not likely," says Kempes. The functions those macromolecules serve, however, and the metabolic scaling relationships observed in organic, Earth-based life, just might be. "Even if life elsewhere used really different molecules, these sort of functional categories and scaling laws might be conserved throughout the universe," says Kempes.

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Deep neural network to find hidden turbulent motion on the sun

Scientists developed a neural network deep learning technique to extract hidden turbulent motion information from observations of the Sun. Tests on three different sets of simulation data showed that it is possible to infer the horizontal motion from data for the temperature and vertical motion. This technique will benefit solar astronomy and other fields such as plasma physics, fusion science, and fluid dynamics.

The Sun is important to the Sustainable Development Goal of Affordable and Clean Energy, both as the source of solar power and as a natural example of fusion energy. Our understanding of the Sun is limited by the data we can collect. It is relatively easy to observe the temperature and vertical motion of solar plasma, gas so hot that the component atoms break down into electrons and ions. But it is difficult to determine the horizontal motion.

To tackle this problem, a team of scientists led by the National Astronomical Observatory of Japan and the National Institute for Fusion Science created a neural network model, and fed it data from three different simulations of plasma turbulence. After training, the neural network was able to correctly infer the horizontal motion given only the vertical motion and the temperature.

The team also developed a novel coherence spectrum to evaluate the performance of the output at different size scales. This new analysis showed that the method succeeded at predicting the large-scale patterns in the horizontal turbulent motion, but had trouble with small features. The team is now working to improve the performance at small scales. It is hoped that this method can be applied to future high resolution solar observations, such as those expected from the SUNRISE-3 balloon telescope, as well as to laboratory plasmas, such as those created in fusion science research for new energy.

From Science Daily

Mystery solved about the origin of the 30,000-year-old Venus of Willendorf

The almost 11 cm high figurine from Willendorf is one of the most important examples of early art in Europe. It is made of a rock called "oolite" which is not found in or around Willendorf. A research team led by the anthropologist Gerhard Weber from the University of Vienna and the two geologists Alexander Lukeneder and Mathias Harzhauser as well as the prehistorian Walpurga Antl-Weiser from the Natural History Museum Vienna have now found out with the help of high-resolution tomographic images that the material from which the Venus was carved likely comes from northern Italy. This sheds new light on the remarkable mobility of the first modern humans south and north of the Alps. The results currently appear in Scientific Reports.

The Venus von Willendorf is not only special in terms of its design, but also in terms of its material. While other Venus figures are usually made of ivory or bone, sometimes also of different stones, oolite was used for the Lower Austrian Venus, which is unique for such cult objects. The figurine found in the Wachau in 1908 and on display in the Natural History Museum in Vienna has so far only been examined from the outside. Now, more than a 100 years later, anthropologist Gerhard Weber from the University of Vienna has used a new method to examine its interior: micro-computed tomography. During several passes, the scientists obtained images with a resolution of up to 11.5 micrometres -- a quality that is otherwise only seen under a microscope. The first insight gained is: "Venus does not look uniform at all on the inside. A special property that could be used to determine its origin," says the anthropologist.

Along with the two geologists Alexander Lukeneder and Mathias Harzhauser from the Natural History Museum in Vienna, who had previously worked with oolites, the team procured comparative samples from Austria and Europe and evaluated them. A complex project: Rock samples from France to eastern Ukraine, from Germany to Sicily were obtained, sawn up and examined under a microscope. The team was supported by the state of Lower Austria, which provided funds for the time-consuming analyses.

The inside also gives information about the outside

The tomographic data from the Venus showed that the sediments were deposited in the rocks in different densities and sizes. In between there were also small remnants of shells and six very dense, larger grains, so-called limonites. The latter explains the previously mysterious hemispherical cavities on the surface of Venus with the same diameter: "The hard limonites probably broke out when the creator of the Venus was carving it," explains Weber: "In the case of the Venus navel, he then apparently made it a virtue out of necessity."

Another finding: The Venus oolite is porous because the cores of the millions of globules (ooides) of which it is comprised had dissolved. This is a great explanation for why the resourceful sculptor chose this material 30,000 years ago: It is much easier to work with. The scientists also identified a tiny shell remnant, just 2.5 millimetres long, and dated it to the Jurassic period. This ruled out all other potential deposits of the rock from the much later Miocene geological era, such as those in the nearby Vienna Basin.

A long way for that time

The research team also analysed the grain sizes of the other samples. Hundreds, sometimes even thousands of grains were marked and measured with image processing programs or even manually. None of the samples within a 200-kilometer radius of Willendorf even remotely matched. The analysis finally showed that the samples from the Venus were statistically indistinguishable from samples from a location in northern Italy near Lake Garda. This is remarkable because it means that the Venus (or at least its material) started a journey from south of the Alps to the Danube north of the Alps.

"People in the Gravettian -- the tool culture of the time -- looked for and inhabited favourable locations. When the climate or the prey situation changed, they moved on, preferably along rivers," explains Gerhard Weber. Such a journey could have taken generations.

One of the two possible routes from the south to the north would lead around the Alps and into the Pannonian Plain and was described in simulations by other researchers a few years ago. The other way to get from Lake Garda to the Wachau would be via the Alps. Whether this was possible more than 30,000 years ago is unclear due to the climate deterioration that began at that time. This would be a rather improbable variant if there had already been continuous glaciers at that time. However, the 730 km long path along the Etsch, the Inn and the Danube had always been below 1,000 meters above sea level, with the exception of 35 kilometres at Lake Reschen.

Possible, but less likely, connection to eastern Ukraine

The statistics clearly point to northern Italy as the origin of the Venus oolite. Nevertheless, there is another interesting place for the origin of the rock. It is in eastern Ukraine, more than 1,600 kilometres linear distance from Willendorf. The samples there do not fit as clearly as those from Italy, but better than all the rest of the sample. An interesting connection here: Venus figures were found in nearby southern Russia, which are somewhat younger, but look very similar to the Venus found in Austria. Genetic results also show that people in Central and Eastern Europe were connected to one another at this time.

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Elephant seal’s map sense tells them when to head ‘home’

Each year, pregnant female elephant seals take an approximately 240-day trek over 10,000 kilometers across the Eastern North Pacific Ocean before returning to their breeding beaches to give birth within five days of their arrival. Now, a study appearing February 28 in the journal biology Current Biology finds that this impressive navigation ability depends on an internal map sense, which functions much like a built-in GPS.

"We found that migrating elephant seals know how far they are from their breeding beach thousands of kilometers away," said Roxanne Beltran of the University of California Santa Cruz. "They also know approximately how long it will take them to get back."

Beltran and her colleagues, including Dan Costa, knew that elephant seals are expert navigators. What they didn't know was how the seals manage to make it back to the beach just in time for the breeding season.

In the new study, the researchers used satellite tracking data collected from more than 100 adult female seals. They figured out when each of them turned around to head back to the beach where they started from.

The data revealed that seals decided to turn around based strongly on how far away they were from where they needed to go. Their decisions to turn around weren't related to their body condition, measured as amount of body fat.

"We were surprised that foraging success or percent body fat was not more strongly related to when seals begin the return portion of the migration," Beltran said. "We expected that highly successful (i.e. fatter) seals might end their foraging trips earlier, but that was not the case; instead, it seems like they are well programmed to turn around strategically based on where they are and in turn how long it will take them to get back."

The researchers don't yet know what sensory cues the elephant seals depend on to keep track of where they are and head in the right direction at the right time, but it's clear that they can adjust the timing of their travels based on an internal perception of time and space.

The results help to better understand elephant seals, with important implications for their conservation, the researchers say. In future studies, they hope to quantify exactly how precise the seals' navigation ability is and determine which cues are most important.

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Computer drug simulations offer warning about promising diabetes and cancer treatment

Using computer drug simulations, researchers have found that doctors need to be wary of prescribing a particular treatment for all types of cancer and patients.

The drug, called metformin, has traditionally been prescribed for diabetes but has been used in clinical settings as a cancer treatment in recent years.

The researchers say while metformin shows great promise, it also has negative consequences for some types of cancers.

"Metformin is a wonder drug, and we are just beginning to understand all its possible benefits," said Mehrshad Sadria, a PhD candidate in applied mathematics at the University of Waterloo. "Doctors need to examine the value of the drug on a case-by-case basis, because for some cancers and some patient profiles, it may actually have the opposite of the intended effect by protecting tumour cells against stress."

The computer-simulated treatments use models that replicate both the drug and the cancerous cells in a virtual environment. Such models can give clinical trials in humans a considerable head-start and can provide insights to medical practitioners that would take much longer to be discovered in the field.

"In clinical settings, drugs can sometimes be prescribed in a trial and error manner," said Anita Layton, professor of applied mathematics and Canada 150 Research Chair in mathematical biology and medicine at Waterloo. "Our mathematical models help accelerate clinical trials and remove some of the guesswork. What we see with this drug is that it can do a lot of good but needs more study."

The researchers say their work shows the importance of precision medicine when considering the use of metformin for cancer and other diseases. Precision medicine is an approach that assumes each patient requires individualized medical assessment and treatment.

"Diseases and treatments are complicated," Sadria said. "Everything about the patient matters, and even small differences can have a big impact on the effect of a drug, such as age, gender, genetic and epigenetic profiles. All these things are important and can affect a patient's drug outcome. In addition, no one drug works for everyone, so doctors need to take a close look at each patient when considering treatments like metformin."

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