Evolution and Global Warming are facts, not theories!

Hand Evolution by Megan Godtland

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Microwave Earth by Megan Godtland

2019 Scientists Stats

120 Evolution News Articles
for April 2020
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Nature cares only that you reproduce and raise the kids.
After you've done that, get out of the way.

4-30-20 People put on ventilators for covid-19 may need lengthy rehabilitation
Health systems need to start ramping up services for helping people recover from intensive care treatment for coronavirus, doctors are warning. After spending several weeks on a ventilator, people will need extensive physical and mental rehabilitation for weeks afterwards. “We’re going to have an epidemic of post-intensive care rehab requirements for people who survived,” says Kathryn Mannix, a palliative care doctor in north-east England. “They’re not going to come back home well.” Many countries are now treating unprecedented numbers of covid-19 patients in intensive care whose lung function has worsened to the point they need mechanical ventilation. To have a tube put down their throat and a machine take over their breathing, they need to be sedated into unconsciousness and receive drugs that paralyse their muscles. Many people at this stage are deteriorating further, with failure of other organs, such as the heart or kidneys. In the UK, just over half of people with covid-19 who need ventilation are dying. For those who survive, the sedation can be slowly lessened – this is a very frightening and bewildering experience, says Brian Cuthbertson at Sunnybrook Hospital in Toronto, Canada. As the opioid medication is reduced, they may suffer hallucinations and agitation, like someone coming off heroin. “A classic terrifying delusion is that the nurse is trying to kill you,” he says. After ventilation, people also feel extremely weak, partly thanks to ordinary muscle wasting because they may have lain in bed for several weeks, and also due to their muscle tissue being broken down as they were critically ill. At first, people may be too weak even to breathe for themselves, so the time they spend off the ventilator has to be slowly increased. For this, the patient needs to have a tracheostomy, when a breathing tube is put into a hole in their neck instead of going down their mouth, so they can easily switch back and forth between breathing independently and on the machine.

4-30-20 Most people’s mental health conditions morph into others over time
Diagnoses of psychiatric conditions can guide a person’s treatment and are useful for mental health research. But a study that followed more than 1000 people for four decades suggests that psychiatry’s over-reliance on specific diagnoses may be misguided, and that many conditions change and overlap with one another over time. The research, led by Avshalom Caspi and Terrie Moffitt of Duke University, North Carolina, drew on the Dunedin Birth Cohort Study, which follows a nationally representative group of more than 1000 New Zealanders born in 1972 and 1973. As the participants in the Dunedin Study have grown up, they have been interviewed and assessed nine times, in order to measure various aspects of their health and behaviour, including their mental health. Analysing this data, Caspi and Moffitt’s team found that by age 45, 86 per cent of the participants had met the criteria for at least one psychiatric diagnosis at one of the nine assessments. This didn’t necessarily mean that they had received a psychiatric diagnosis – but if they had gone to see a psychiatrist, they could have been given one. The finding underscores just how widespread mental health issues are. The analysis found that a third of the cohort met the criteria for a psychiatric diagnosis before they reached the age of 15. Yet over time, these diagnoses usually shifted between three major families of conditions that psychiatrists describe as internalising (including depression, bipolar disorder and anxiety), externalising (which includes substance abuse) and disordered thought (which includes schizophrenia, obsession and compulsions). Of those who met the criteria for a disordered-thought condition at some point in their lives so far, 98 per cent had also met the criteria for a diagnosis from the other two categories at at least one of their assessments. This was true for more than 76 per cent of those who at some stage met the criteria for an externalising condition, and more than 70 per cent of those who were found at at some point to satisfy the criteria for an internalising condition. The researchers argue that this reinforces the idea that many psychiatric conditions can share common causes.

4-30-20 How coronavirus is affecting your dreams – and what to do about it
If you feel you’ve been dreaming a lot more recently, the coronavirus crisis and lockdown measures could be to blame. Changes in sleep patterns may mean that many of us are dreaming more or remembering more of the dreams that we have, while the looming threat of the virus may have affected the nature of the dreams themselves. According to a survey conducted by King’s College London, 62 per cent of people in the UK are getting just as much sleep, if not more, than before stricter social distancing measures began on 23 March. Similar patterns are likely in other countries, and it is reasonable to assume that for some of those staying at home, the time saved from getting ready for work and commuting is being used to get more sleep. This means dream time and dream recall is probably increasing during the crisis, says Mark Blagrove, a psychologist at Swansea University, UK. When you sleep for longer, you have more rapid eye movement (REM) sleep. This is the sleep stage from which most dreams are recalled. Modern life, however, typically involves shortened sleep and may be leading to an “epidemic” of dream loss. That may now be changing for some. “Lack of work schedules may be allowing individuals to wake up without an alarm clock,” says Blagrove. “Natural wake-ups are known to result in longer dreams.” At the same time, anxiety can disrupt our sleep, leading to more awakenings. When you awaken out of REM sleep, you’re much more likely to remember the dream you were having. The content and tone of our dreams is also probably being affected. “Our dreams are more likely to incorporate memories from recent waking life that are emotional,” says Blagrove. “Dreams are thought to be the brain’s way of working out our emotional problems, and the more anxious we become, the more vivid the dream images become,” says Russell Foster, a circadian neuroscientist at the University of Oxford. “After 9/11, many New Yorkers reported dreams of being overwhelmed by a tidal wave or being attacked and robbed.”

4-30-20 Transatlantic slavery introduced infectious diseases to the Americas
Viral and bacterial DNA found in the remains of three African slaves in Mexico suggests that the transatlantic slave trade may have introduced new infectious diseases into the Americas. This discovery highlights the slave trade’s impact on the spread of diseases during the colonial period, between the 1500s and 1800s, says Rodrigo Barquera at the Max Planck Institute for the Science of Human History in Germany. Barquera and his colleagues analysed the remains of people who were buried in a mass grave, first uncovered in the early 1990s, near the Royal Hospital of San José de los Naturales in what is now Mexico City. DNA and chemical analysis of the remains suggested three of the individuals were of African descent, rather than Native American, and showed that they were male. Carbon dating of their skeletons revealed that they died soon after the start of the colonial period in Mexico, suggesting they were enslaved people, since slavery was the main way that Africans came to the region during this time. Their bones revealed skeletal changes consistent with intense labour and heavy manual activity as well as gunshot wounds and signs of malnutrition. The researchers were able to extract viral and bacterial DNA from the teeth of all three individuals. They discovered DNA from the hepatitis B virus (HBV) and from bacteria responsible for a disease called yaws, which is similar to syphilis and was common in Mexico during the colonial period. “We didn’t expect to recover genomes from such important pathogens,” says Barquera. “These are the earliest human remains in the Americas in which HBV and yaws have been identified so far, suggesting that the slave trade may have introduced these diseases into Latin America very early into the colonial period.” DNA sequences from these pathogens revealed their close relationship to strains circulating in current West African populations, indicating that the three individuals probably contracted the diseases before they were forcefully brought to Mexico.

4-30-20 Remdesivir is the first drug found to block the coronavirus
Preliminary results suggest that an antiviral treatment speeds recovery from COVID-19. An antiviral drug called remdesivir is the first treatment to show efficacy against the coronavirus. Preliminary results from a clinical trial comparing the drug with a placebo suggest that remdesivir speeds recovery from COVID-19 by 31 percent, the U.S. National Institute of Allergy and Infectious Diseases said April 29 in a news release. The international trial randomly assigned 1,063 people hospitalized with COVID-19 to get intravenous infusions of either remdesivir or a placebo. In the remdesivir group, the median time to recovery was 11 days, compared with 15 days for those on the placebo. Recovery was defined as being discharged from the hospital or being well enough to resume normal activity. Eight percent of people in the remdesivir group died, compared with 11 percent in the placebo group. “Although a 31 percent improvement doesn’t seem like a knockout 100 percent, it is a very important proof of concept,” Anthony Fauci, director of the NIAID, said April 29 during a news briefing at the White House. “It has proven that a drug can block this virus.” Normally, researchers would have waited to make the announcement until the results had been reviewed by other scientists, but the team chose to make the announcement early, Fauci said. “Whenever you have clear-cut evidence that a drug works, you have an ethical obligation to immediately let the people who are in the placebo group know so that they can have access.” Remdesivir will now be the standard of care by which other drugs are judged, Fauci said. The trial will be adapted to add to the remdesivir treatment an antibody that may protect against inflammation, he said. Remdesivir, developed by biopharmaceutical company Gilead Sciences, headquartered in Foster City, Calif., mimics a building block of RNA, the coronavirus’s genetic material. When the virus copies its RNA, remdesivir is incorporated instead of the usual RNA components, stopping the virus’s replication.

4-30-20 Coronavirus R0: Is this the crucial number?
There is a simple, but crucial number at the heart of understanding the threat posed by the coronavirus. It is guiding governments around the world on the actions needed to save lives, and it gives us clues to the extent that lockdown can be lifted. It is called the basic reproduction number or simply the R0 (pronounced R-nought). The reproduction number is a way of rating a disease's ability to spread. It's the number of people that one infected person will pass the virus on to, on average, assuming that nobody is immune and people don't change their behaviour to avoid getting ill. Measles has one of the highest numbers in town with a reproduction number of 15. It can cause explosive outbreaks. The new coronavirus, known officially as Sars-CoV-2, has a reproduction number of about three, but estimates vary. If the reproduction number is higher than one, then the number of cases increases exponentially - it snowballs like debt on an unpaid credit card. But if the number is lower, the disease will eventually peter out as not enough new people are being infected to sustain the outbreak. Governments everywhere want to force the reproduction number down from about three to below one. This is the reason you've not seen family, have had to work from home and the children have been off school. Stopping people coming into contact with each other to cut the virus's ability to spread. The reproduction number is not fixed. Instead, it changes as our behaviour changes or as immunity develops. Mathematical modellers at Imperial College London are attempting to track how the number has changed as isolation, social distancing and the full lockdown were introduced. Before any measures came in, the number was well above one and the conditions were ripe for a large outbreak. Successive restrictions brought it down, but it was not until full lockdown that it was driven below one. It's a bit technical but by this point scientists refer to the Rt, rather than R0, as the number is changing over time. The figure now seems to be about 0.7. There is always some uncertainty in this type of work, but there is a high degree of confidence from the government's scientific advisers that the figure is below one overall. The situation is different in some hospitals and care homes where the virus is spreading

4-30-20 A ‘crazy beast’ from the time of dinosaurs belongs to an obscure mammal group
A bizarre fossil provides a better look at a little-known group called gondwanatherians. The ancient mammal Adalatherium hui is so weird that it eluded classification for over a decade. A roughly 70-million-year-old skeleton of the species, uncovered in Madagascar in 1999, was clearly a mammal. But it boasted several distinctly un-mammalian features, such as a large hole on top of its snout. Also, although the animal’s forelimbs were aligned with its spine, like a typical mammal, its back legs were splayed out to the sides like a reptile. “It is so strange, compared to any other mammal, living or extinct,” says paleontologist David Krause, of the Denver Museum of Nature & Science, “it was just crazy.” Hence the name Adalatherium hui, from a Malagasy word meaning “crazy” and the Greek word for “beast.” Now, the crazy beast finally has been identified as a gondwanatherian — an obscure group of mammals that roamed the Southern Hemisphere during the age of dinosaurs, Krause and colleagues report online April 29 in Nature. The key to the animal’s identity was in comparing the skeleton to an intact skull from a different gondwanatherian species, discovered in 2014 also in Madagascar. The arrangement of bones in the snout of the skull matched that of Adalatherium hui, establishing the animals as relatives. Placing Adalatherium hui among the gondwanatherians gives new insight into how this enigmatic group of animals fit into the mammal family tree. Up to 2014, the only other known traces of gondwanatherians were a handful of teeth and jaws. Given the historically sparse fossil record for gondwanatherians, “we knew very little about their anatomy,” and therefore how they were related to other ancient animals, Krause says.

4-30-20 Spinosaurus fossil tail suggests dinosaurs were swimmers after all
The predator’s tail was paddlelike, with a range of motion that allowed swinging side to side. Sharp-toothed Spinosaurus didn’t just stand in the shallows to snag fish for dinner; this dinosaur may have been an excellent swimmer. Spinosaurus aegyptiacus, a new fossil discovery reveals, had a paddle-shaped tail that may have helped the predator slice through the water with the grace of a crocodile. The fossilized tail, unearthed from 95-million-year-old rocks in Morocco, is the most complete Spinosaurus tail ever recovered. Its unusual shape suggests that this dinosaur may have been aquatic — contrary to prevailing wisdom that dinosaurs were solely land dwellers, researchers report in a study published online April 29 in Nature. “It was basically a river monster,” says Nazir Ibrahim, a vertebrate paleontologist at the University of Detroit Mercy who led the study. “When I first saw the illustrations of the tail, I literally giggled with surprise and delight — and I’m not someone who usually giggles,” says Matthew Lamanna, a vertebrate paleontologist at the Carnegie Museum of Natural History in Pittsburgh, who reviewed the paper for Nature. “The tail was just so awesomely weird-looking for a predatory dinosaur. I’d never seen anything like it.” Spinosaurus was known to have lived near the water and to have dined on seafood: The animal’s cone-shaped teeth would have been adept at snagging slippery fish. “But for most people, the model they were more comfortable with was a wading dinosaur that waited for the fish to swim by,” the way a grizzly bear may splash into the water to catch a fish, Ibrahim says. Ibrahim has previously proposed that Spinosaurus was more than an occasional wader. In a 2014 paper in Science, he and colleagues reported that the creature had denser bones than most other theropods, the branch of predatory dinosaurs that includes Tyrannosaurus rex and Allosaurus (SN: 9/11/14). Denser bones could be an evolutionary adaptation to a more aquatic life, allowing for greater buoyancy control.

4-29-20 Why it’ll still be a long time before we get a coronavirus vaccine.
Trials of experimental coronavirus vaccines are already under way, but it’s still likely to be years before one is ready and vaccination may not even be possible. MANY UK newspapers recently celebrated the first volunteer to receive an injection as part of a safety trial of an experimental coronavirus vaccine. But while there are claims that it could be possible for a vaccine to be ready within a year, the chances of this happening remain slim. The UK trial, led by the University of Oxford, will ultimately involve 1100 adults, half of whom will receive the experimental vaccine. The other half will get a meningitis vaccine as a control. The team behind the trial hopes to move on to tests to gauge how effective the vaccine is against the coronavirus as early as August, raising hopes that a vaccine could be ready before the end of the year, and that this could be the answer to the difficult question of how the country gets out of strict social distancing measures. Unfortunately, these hopes are probably misplaced. Vaccine design expert Maria Bottazzi of Baylor College of Medicine in Houston, Texas, calls the schedule “unrealistic”. Even if everything goes according to plan in the first phase of trials, Bottazzi points out that researchers will still need time to determine how well the vaccine protects people from covid-19 and whether it provokes any side effects when a vaccinated person is subsequently exposed to the virus. It is far from guaranteed that the vaccine will be safe and effective. 2013 study calculated that, before entering clinical trials, the average experimental vaccine has a 6 per cent chance of ultimately reaching the market. Of those that make it into trials, a 2019 analysis suggests the probability of success is 33.4 per cent. But even if the Oxford vaccine succeeds, there will then be the issue of scaling up manufacturing to make hundreds of millions of doses. According to Bottazzi, this is the real bottleneck. Under the best of circumstances, the world is still looking at 12 to 18 months before a vaccine could be widely available, she says.

4-29-20 We must act quickly to avoid a pandemic-related mental health crisis
We are already seeing the pandemic's effects on mental health, and we need to act urgently to avoid a full-blown crisis, says Sam Howells. Because of the coronavirus pandemic, many people cannot leave their homes except to buy food or exercise briefly. They cannot see their friends or family, or go to work, and the near-term outlook is bleak. This combination is the perfect storm for an increase in mental health conditions and we are already beginning to see signs that an associated mental health pandemic is under way. I am on the front line. I work as a psychological healthcare professional for England’s National Health Service in a programme called Improving Access to Psychological Therapies (IAPT). This is the first point of call for mental health conditions in much the same way that family doctors are for issues with physical health. We are anticipating explosive growth in mental health problems that far exceeds our current capacity. Serious societal and economic disruption is nearly always associated with a surge in such problems. Within a month of the 9/11 attacks, for example, around 10 per cent of New York residents showed signs of diagnosable major depressive disorder. During the SARS outbreak in 2003, there was a substantial rise in reported cases of depression, anxiety, panic attacks, psychosis and suicidal thoughts in China, for example, although precise figures remain elusive as mental health problems are still often stigmatised. A growing number of our patients report that isolation and a general sense of physical, social and economic vulnerability are triggering existing and new psychological problems, and the pandemic is hampering our ability to deal with them. Due to homeworking restrictions, my colleagues and I are relying almost solely on virtual technology to treat people, which hasn’t yet been proven at this scale. At the same time, IAPT staff are being diverted into hospitals to bolster overburdened physical healthcare wards.

4-29-20 Rotten fish smell could detect awareness in people with brain injuries
A waft of rotten fish might help doctors looking for signs of awareness in people who are unresponsive after serious brain injury. It can be hard to know if people in this condition are in a vegetative state, when they cannot see or feel anything, or if they have some awareness but are almost paralysed. Doctors investigate this with tests such as asking people to follow a moving finger with their eyes, but for those in this “minimally conscious state”, awareness typically fluctuates over time, so they may be wrongly assumed to be vegetative. Anat Arzi at the Weizmann Institute of Science in Rehovot, Israel wondered if people with some awareness would show any response to smells, as non-injured people reduce the air they inhale in the presence of bad smells, both consciously and unconsciously. We even show a small “sniff response” to odours in our sleep. “The brain has the capacity to process information when we are not consciously aware, probably for survival reasons,” says Arzi. Her team investigated 43 people in a rehabilitation facility in the first few weeks or months after a brain injury. About half were thought to be in a vegetative state, and the rest were thought to be minimally conscious. A small tube entering the nose could measure the volume of air they inhaled. Some people in both groups showed about a ten per cent reduction in inhaled air when presented with a strong odour – whether it was of liquid that smelled like rotten fish or simply a fruity shampoo. The test was most revealing for the 24 people classed as vegetative. Of those, 16 were later diagnosed as minimally conscious because they had started showing some responses, such as eye movements. Ten of these had showed a sniff response, but none of those who stayed in a vegetative state had had one.

4-29-20 Pondering the big question of consciousness is a welcome distraction
Our best mathematical theory of consciousness is sparking a rethink of one of science’s hardest problems – how simple matter gives rise to a complex mind. LIFE at the moment seems full of questions where everyone has an opinion, but few can supply a convincing answer. By way of diversion, let us instead consider a question that invites few coherent opinions, but screams what seems to be a correct answer. Ask “is the universe conscious?”, as we do on this week’s cover, and the brain-jerk answer is “no”. Consciousness is a case of the haves and have nots. Humans clearly have it; a rock, a star or other agglomeration of physical matter, such as the wider cosmos, doesn’t. The venerable philosophical idea of universal sentience, or “panpsychism”, says otherwise when it comes to inanimate things, but it seems to have no more place in modern science than a belief in fairies at the end of the garden. However, an enquiring mind does well to leave its intuitions at the door. How certain arrangements of matter such as the neuronal circuits in our brains give rise to felt experience, while others don’t, is a “hard problem”. It is difficult to set boundaries on consciousness when we don’t really know what it is. Does an octopus have it? A tree? A bacterium? A sentient robot? Propose that all matter has consciousness in some form, differing only in degree, and you go some way to setting aside such basic problems. That still isn’t an argument. But the realisation that our mathematically most mature theory of consciousness, integrated information theory, gives succour to panpsychism, could well be. Mathematics has, in physicist Eugene Wigner’s phrase, shown an “unreasonable effectiveness” in tackling hard problems of science, and has been an extraordinary way of leading us to enlightenment by subverting intuitions. Just ask any student of quantum theory or relativity where those theories lie in relation to the grain of our brains.

4-29-20 How the turtle got its shell: Amazing fossils are solving the mystery
For years, the oldest turtle fossils we could find had fully formed shells. Now, more primitive fossils are revealing the strange tale of how turtle shells evolved. CONSIDER the floating fortress that is a sea turtle. It seems to fly gracefully through the water even though it is encased in heavy armour. This combination of poise and protection evolved like any wonder of the animal kingdom, yet until recently the fossils we had found made it seem as if they emerged fully formed hundreds of millions of years ago. In fact, scientists who study the evolution of these animals have a running joke: turtles might as well have come from space. In the past few years, however, truly ancient fossils have been discovered and they are helping to unravel this real-life just-so story. As we uncover fresh clues, we are learning that the tale of how the turtle got its shell reads nothing like we had previously guessed. In the UK, the word “turtle” usually refers to the reptiles that swim in the sea, but these are just one branch of a larger group that includes species that burrow in desert sand and slog through swamps. Whether we are talking about a Galapagos tortoise, green sea turtle or red-eared terrapin at the pet shop, they all belong to an order called Testudines – which zoologists tend to call the turtles or chelonians. All living animals in this order are united by their shell and the modifications required to live inside this box of bone. Their upper ribs are fused to the inside of their shell and their shoulder joints are set inside their ribs. This anatomical form is unprecedented among vertebrates. Imagine how your arms would move – or rather wouldn’t – if your shoulders were inside your ribcage. “It is the shell and associated features, such as the position of the limb girdles inside it, that makes turtles so unusual,” says palaeontologist Hans Sues at the Smithsonian National Museum of Natural History in Washington DC.

4-29-20 'Crazy beast' lived among last of dinosaurs
A cat-sized mammal dubbed "crazy beast" lived on Madagascar among some of the last dinosaurs to walk the Earth, scientists have revealed. The 66-million-year-old fossil is described in the journal Nature. Its discovery challenges previous assumptions that mammals were generally very small - the size of mice - at this point in their evolutionary history. Researchers say this individual animal weighed 3kg (6.6lbs) and had not reached its full adult size. Scientists think that the badger-like creature, known as Adalatherium hui, would have burrowed. It had a large collection of nerves in the snout, making this area extremely sensitive - a feature frequently seen in burrowing animals. Before mammals took over the Earth, they probably had to run and hide from the much larger dinosaurs that ruled our planet - not to mention other predators. The fossil specimen was found in 1999 in north-west Madagascar's Mahajanga Basin. It is the most complete and best-preserved mammal find from Gondwana - an ancient southern supercontinent that once included India and Africa - during the time of the dinosaurs. However, when this mammal was alive, Gondwana was breaking up, and Madagascar had already become an island. The team members think Adalatherium would have faced different types of predator, as well as different food sources, on the island to mammals living on the mainland. This may have led to the animal evolving its large size. The very complete specimen gives scientists a rare insight into a branch of mammals - known as Gondwanatherians - that have now gone extinct.

4-29-20 Massive Spinosaurus dinosaur swam through water propelled by its tail
A predatory dinosaur that was bigger than Tyrannosaurus rex may have been able to use its tail to swim through water, allowing it to hunt aquatic prey. “It opens up an entire new world of ecological possibilities for dinosaurs,” says Nizar Ibrahim at the University of Detroit Mercy. Ibrahim and his colleagues analysed a 95 million-year-old fossilised tail of Spinosaurus aegyptiacus, which they first unearthed in the Kem Kem beds in south-eastern Morocco in 2018. They discovered that the dinosaur’s tail had an unusual paddle-like shape, with long spines near the tip, and was far more flexible than previously thought. “It came as a massive surprise, because nothing like this has been documented in any other dinosaur,” says Ibrahim. This flexible tail indicates the dinosaur would have been able to propel itself in the water. This suggests it was actively hunting for prey in deeper waters, says Ibrahim. Previous studies have shown that Spinosaurus had adaptations for fish-eating. “But it was generally considered a wader, possibly waiting for fish to swim by, while standing in shallow waters,” says Ibrahim. “It may mean some of these [types of] dinosaurs had distinct behaviours, entering the water in a more significant way than we have previously thought,” says Steven Jasinski at the State Museum of Pennsylvania. The new tail bones and shape of the tail add to evidence from other parts of its anatomy, such as its retracted nostrils and solid limb bones, that indicate this predator was adapted to swimming and feeding in water, says Paul Sereno at the University of Chicago in Illinois. “I don’t think it was very fast or agile in water,” says Sereno. “Many aspects of its body form and feet are not suitable for aquatic speed or agility,” he says. Spinosaurus was around 15 metres long, 3 metres longer than T. rex, making it likely the largest carnivorous dinosaur. It also had a large sail on its back.

4-29-20 What coronavirus antibody tests tell us — and what they don’t
Widespread testing could reveal who has had COVID-19, but not whether they’ll get it again. As some countries begin to reopen in the midst of the ongoing coronavirus pandemic, experts are racing to ramp up the development and use of blood tests that pinpoint people who have been exposed to the virus that causes COVID-19 and are no longer infected. The tests detect antibodies, proteins made by the immune system to fight infection (SN: 3/27/20). People who carry antibodies specific to the novel coronavirus, called SARS-CoV-2, have been infected previously, even if they didn’t know it. For those people, discovering that they have these virus-fighting antibodies could raise hopes of immunity and a return to normal life. But scientists are also working to uncover what these blood tests really tell us. At this point, there isn’t enough evidence to confirm that recovered people are protected from the disease and, if so, for how long, the World Health Organization said in a statement on April 24. So people hoping for that assurance may be disappointed. For researchers and public health officials, though, the tests can reveal the true extent of the pandemic. The U.S. National Institutes of Health announced April 10 that researchers had begun recruiting people for a nationwide study that aims to test as many as 10,000 volunteers without an official COVID-19 diagnosis, which could help clarify how many people across the country have actually been infected. A number of similar, more local studies are also under way. The goal is to fill in the gaps created by trouble rolling out diagnostic tests, which detect the virus’s genetic material and can catch an active infection. Those tests have faced roadblocks such as flawed tests and supply shortages, leaving some sick people wondering whether their symptoms were from COVID-19 or a different respiratory infection.

4-29-20 Vaping may damage the heart just as smoking does
Both vapers and smokers show signs of blood vessel damage, compared with people who do neither. Switching from smoking to vaping may not help with cardiovascular health. Researchers performed tests on the vascular systems of more than 400 healthy adults aged 21 to 45. Study participants who use cigarettes, e-cigarettes or both had stiffer arteries than those who did not smoke or vape, the researchers report online April 29 in the Journal of the American Heart Association. That stiffness can damage small blood vessels and strain the heart, both of which can contribute to the development of cardiovascular disease, says Jessica Fetterman, a vascular biologist at Boston University School of Medicine. Fetterman and colleagues also collected participant samples of cells lining the blood vessels, and exposed those cells to a fluorescent dye that detects nitric oxide, a molecule that dilates blood vessels and helps stop blood from clotting. Cells taken from smokers and vapers produced less nitric oxide than cells from participants who did not smoke or vape, a sign that smokers’ and vapers’ blood vessels may not be functioning normally. Cardiovascular disease is a major cause of death for smokers, and some have suggested that switching to e-cigarettes might prove less harmful to health. Many adults who vape are former smokers, and that was true for the e-cigarette users in this study. The study participants who vaped had been doing so for at least three months. Previous research has shown that healthy smokers who quit can see a reduction in the stiffness of their arteries in as little as four weeks. “Our work suggests that the abnormalities in vascular stiffness persist in e-cigarette users,” Fetterman says. “There was no evidence that the use of e-cigarettes reduces cardiovascular injury” associated with smoking combustible cigarettes.

4-28-20 Drinking coffee appears to cause epigenetic changes to your DNA
Drinking coffee may change how some of our genes are expressed, which could help explain its numerous health benefits. Studies suggest that people who drink coffee are less likely to get certain illnesses, such as heart disease, but we don’t know why. To learn more, Mohsen Ghanbari at Erasmus University Medical Center in Rotterdam, the Netherlands, and his colleagues looked at whether coffee consumption is associated with the presence of certain epigenetic markers – chemical tags on DNA – that increase or decrease the activity of certain genes that may influence health. They looked for particular markers known as methyl groups in almost 16,000 people of European and African American descent in the the US and Europe. The more cups of coffee a person drank per day, the more likely they were to have altered levels of methyl groups at 11 particular DNA sites. This was still true after age, body mass index, smoking, alcohol consumption and other factors that may have influenced the results were taken into account. The methyl groups tended to be attached to genes that play roles in digestion, processing harmful chemicals and controlling inflammation. These are “tantalising clues” to how epigenetics could explain some of coffee’s health effects, says Peter Molloy at the Commonwealth Scientific and Industrial Research Organisation in Australia. But more studies are needed to prove that the markers alter the activity of these genes and that this affects our health, he says.

4-28-20 How to deal with your kid's minor injuries at home
Pandemic or no, children are going to get hurt. What can parents treat at home, and when should they seek medical attention? The coronavirus pandemic has forced most of us to stay home unless we have an "essential" reason to leave. There's an amount of risk with every outing, and this is especially true when considering whether to enter a medical setting. We don't want to expose ourselves or anyone else to infection. We also want to avoid putting extra pressure on a health-care system that's already under strain. This presents parents of injured children with a difficult question: Should we go to the doctor or emergency room, or can I deal with this at home? "Parents have always been able to treat a whole host of injuries at home, from minor scrapes and cuts to burns and eye-splashes," says Cara Natterson, M.D., pediatrician and author of Decoding Boys: New Science Behind the Subtle Art of Raising Sons. She recommends parents start by bookmarking a couple of websites: poison Control for questions about ingestions, and Healthy Children, the American Academy of Pediatrics' parenting portal for advice on treating minor bumps and bruises. Most children's hospitals also have websites that can help you decide whether you need to be seen with a specific injury in the first place — so find your local one and bookmark it too. And while COVID-19 has changed our lives in endless ways, it hasn't changed what parents should stock in their first aid kit. "Rubbing alcohol can be used to disinfect, and hydrogen peroxide and saline to clean minor cuts and abrasions," Dr. Uquillas says. "Bandages of different shapes and sizes can also be very useful for small cuts and abrasions. Other essentials are adhesive tape, super glue, an eye shield, cotton balls or swabs, scissors, hand sanitizer, scissors, and a thermometer. Dr. Natterson also has eye wash, instant hot and cold packs, gloves, and some basic medications like ibuprofen, acetaminophen and diphenhydramine (Benadryl) in her own at-home first aid kit. And if you have family members with severe allergies, make sure your EpiPens are in stock and up to date; likewise, inhaler or nebulizer medications should be on hand for those with asthma. So, back to the big question: What kinds of things can be treated easily at home?

4-28-20 Coronavirus immunity: Can you catch it twice?
Can you catch coronavirus again? Why are some people sicker than others? Will it come back every winter? Will a vaccine work? Could immunity passports get some of us back to work? How do we manage the virus in the long-term? The immune system is at the heart of some of the most important questions about the coronavirus. The problem is we know very little. Our immune system is the body's defence against infection and it comes in two parts. The first is always ready to go and leaps into action as soon as any foreign invader is detected in the body. It is known as the innate immune response and includes the release of chemicals that cause inflammation and white blood cells that can destroy infected cells. But this system is not specific to coronavirus. It will not learn and it will not give you immunity to the coronavirus. Instead you need the adaptive immune response. This includes cells that produce targeted antibodies that can stick to the virus in order to stop it and T cells that can attack just the cells infected with the virus, called the cellular response. This takes time - studies suggest it takes around 10 days to start making antibodies that can target the coronavirus and the sickest patients develop the strongest immune response. If the adaptive immune response is powerful enough, then it could leave a lasting memory of the infection that will give protection in the future. It is not known if people who have only mild symptoms, or none at all, will develop a sufficient adaptive immune response. The immune system's memory is rather like our own - it remembers some infections clearly, but has a habit of forgetting others. Measles is highly memorable - one bout should give life-long immunity (as the weakened version in the MMR vaccine does). However, there are many others that are pretty forgettable. Children can get RSV (respiratory syncytial virus) multiple times in the same winter. The new coronavirus, called Sars-CoV-2, has not been around long enough to know how long immunity lasts, but there are six other human coronaviruses that can give a clue. Four produce the symptoms of the common cold and immunity is short-lived. Studies showed some patients could be re-infected within a year.

4-28-20 What coronavirus antibody tests tell us — and what they don’t
Widespread testing could reveal who has had COVID-19, but not whether they’ll get it again. As some countries begin to reopen in the midst of the ongoing coronavirus pandemic, experts are racing to ramp up the development and use of blood tests that pinpoint people who have been exposed to the virus that causes COVID-19 and are no longer infected. The tests detect antibodies, proteins made by the immune system to fight infection (SN: 3/27/20). People who carry antibodies specific to the novel coronavirus, called SARS-CoV-2, have been infected previously, even if they didn’t know it. For those people, discovering that they have these virus-fighting antibodies could raise hopes of immunity and a return to normal life. But scientists are also working to uncover what these blood tests really tell us. At this point, there isn’t enough evidence to confirm that recovered people are protected from the disease and, if so, for how long, the World Health Organization said in a statement on April 24. So people hoping for that assurance may be disappointed. For researchers and public health officials, though, the tests can reveal the true extent of the pandemic. The U.S. National Institutes of Health announced April 10 that researchers had begun recruiting people for a nationwide study that aims to test as many as 10,000 volunteers without an official COVID-19 diagnosis, which could help clarify how many people across the country have actually been infected. A number of similar, more local studies are also under way. The goal is to fill in the gaps created by trouble rolling out diagnostic tests, which detect the virus’s genetic material and can catch an active infection. Those tests have faced roadblocks such as flawed tests and supply shortages, leaving some sick people wondering whether their symptoms were from COVID-19 or a different respiratory infection.

4-28-20 Some patients who survive COVID-19 may suffer lasting lung damage
The similar respiratory disease SARS left lasting lung injury in some patients. Among patients who have recovered from COVID-19 in China comes the first evidence that some may suffer long-term lung damage from the disease. In 70 patients who survived COVID-19 pneumonia, 66 had some level of lung damage visible in CT scans taken before hospital discharge, researchers report March 19 in Radiology. The damage ranged from dense clumps of hardened tissue blocking blood vessels within the tiny air sacs called alveoli, which absorb oxygen, to tissue lesions around the alveoli, Yuhui Wang, a radiologist at Huazhong University of Science and Technology in Wuhan, China, and colleagues found. The tissue lesions can be a sign of chronic lung disease. Similar damage has been documented in survivors of SARS and MERS, respiratory diseases caused by coronaviruses similar to the SARS-CoV-2 virus behind COVID-19. Long-term studies of SARS patients have shown that roughly a third of people who recovered from severe bouts were left with permanent lung damage. In the case of MERS, one study found about a third of people who recovered from a serious infection still had signs of lung damage about seven months later. But while initial lung images indicate that SARS and MARS typically set into just one lung, COVID-19 appears to be more likely to afflict both lungs right away. In 75 of the 90 patients admitted to Huazhong University Hospital with COVID-19 pneumonia from January 16 to February 17, damage was seen across both lungs, Wang and colleagues report. CT scans taken before hospital discharge revealed that 42 out of 70 patients displayed the type of lesions around the alveoli that are more likely to develop into scars. Given how widely the pandemic has spread, chronic lung conditions from COVID-19 could challenge many thousands of people in years to come. As of April 27, more than 2.9 million people worldwide have been diagnosed with the disease. In comparison, SARS, or severe acute respiratory syndrome, sickened about 8,000 people during its 2003–2004 outbreak. MERS, or Middle East respiratory syndrome, has infected more than 2,500 people (SN: 1/24/20). While an estimated 80 percent of COVID-19 cases are mild, the rest display problems ranging from breathing difficulties to respiratory failure (SN: 2/25/20).

4-27-20 Electrical devices implanted in the brain may help treat anorexia
Some women with severe anorexia have returned to a healthy weight and feel less anxious and depressed after having electrical devices implanted into their brains, according to a small study. But more research is needed before the treatment can be recommended for wider use. About one in five people with anorexia nervosa, who are mostly women, die of the illness and there is a lack of effective treatments. Imaging studies suggest that certain brain circuits may underlie the fear of gaining weight and compulsion to self-starve. Bomin Sun at Shanghai Jiao Tong University School of Medicine in China and his colleagues wondered whether they could disrupt these circuits by electrically stimulating a part of the brain known as the nucleus accumbens. This brain region helps us to learn from experience, but in people with anorexia it seems to form abnormal connections with other brain regions. The team recruited 28 women with at least a three-year history of anorexia who hadn’t improved following standard treatment. The women had an average body mass index (BMI) of 13; a BMI of less than 18.5 is considered underweight. The researchers surgically implanted electrodes into the nucleus accumbens on both sides of the women’s brains. They connected the electrodes by wires to a battery inserted beneath the collarbone, to continuously stimulate the nucleus accumbens. Over the next two years, the average BMI of the participants increased to 18 and almost half regained a BMI of 18.5 or above. They also reported feeling fewer anxiety and depression symptoms and experiencing less of an effect on their social lives. “This is a very promising result,” says Philip Mosley at QIMR Berghofer Medical Research Institute in Australia. But the study didn’t include a placebo group for comparison, meaning it isn’t possible to rule out that the participants’ improvement was simply because they expected the treatment to work, says Mosley.

4-27-20 Skeletal damage hints some hunter-gatherer women fought in battles
Traditional views of females being largely responsible for gathering food may be too simplistic. Women’s reputation as nurturing homebodies who left warfare to men in long-ago societies is under attack. Skeletal evidence from hunter-gatherers in what’s now California and from herders in Mongolia suggests that women warriors once existed in those populations. Two research teams had planned to present these findings April 17 at the annual meeting of the American Association of Physical Anthropologists. That meeting was canceled due to the coronavirus pandemic. The results have been provided to Science News by the scientists. Sexual divisions of labor characterized ancient societies, but were not as rigidly enforced as has often been assumed, the new studies suggest. “The traditional view [in anthropology] of ‘man the hunter and woman the gatherer’ is likely flawed and overly simplistic,” says forensic anthropologist Marin Pilloud of the University of Nevada, Reno. Consider hunter-gatherers who lived in central California as early as around 5,000 years ago as well as more recent Native Americans groups in that region, such as Coast Miwok and Yana. Some archaeological evidence as well as historical accounts and 20th century anthropologists’ descriptions generally portray men in those groups as hunters, fishers and fighters in tribal feuds and conflicts with outside armies. Women are presented as focused on gathering and preparing plant foods, weaving and child care. But skeletons of 128 of those hunter-gatherer women display damage from arrows and sharp objects such as knives comparable to skeletal injuries of 289 presumed male warriors, Pilloud and her colleagues found. Whether those women fought alongside men or carried out other dangerous battle duties, such as sneaking up on enemies to cut their bow strings, can’t be determined from their bones. Individuals in this sample came from 19 Native American groups in central California, and had lived in any of five time periods between around 5,000 and 200 years ago.

4-27-20 American optimism is becoming a problem
The perils of cheery positivity during a pandemic. America is a nation addicted to optimism. We look forward to the future and assume it will be better than today. And we always have. That conviction brought the first settlers to our shores and then the successive waves of immigrants that followed, most of them convinced that they could make a better life for themselves. Faith in the future has fueled our incredible economic dynamism and technological advancements down through the centuries. It even inspires our reactionaries, who assure their devoted followers that recent signs of decline can be reversed and America made great once again. But what if this national trait no longer suits the reality of the world we now inhabit? That question has haunted me these past two months, as the coronavirus has shut down the world and killed tens of thousands of Americans (with no end in sight). I've never been a cheerleader for America's inveterate optimism. Yes, it's inspired many of our most impressive achievements down through the centuries. But it also tends to blind us to the ineradicably tragic dimensions of life — the unavoidable trade-offs among competing goods that place hard limits on human striving — and sometimes it even lures us into making terrible (and terribly obvious) mistakes. Whatever else it was, the 2003 invasion of Iraq was an expression of thick-headed American optimism about our capacity to bring liberal democracy to an entire region of the world at the point of a gun. But the Iraq debacle was merely one (albeit very large) event in a broader world that still seemed to bend to our will most of the time, especially in economic matters. Ever-expanding markets, new opportunities for growth, wealth creation beyond the wildest dreams of human beings prior to the postwar world — the possibilities have seemed endless, the horizons boundless. Sure, there have been bumps in the road, like the financial crisis of 2008. But we got past that, too. The market tanked and trillions were lost. But 10 years later, it had bounced back, with trillions more created. And that's how it always works out, isn't it? There are glitches and speculative bubbles. Economies contract. Money vanishes, sometimes a lot of it. Yet the longer-term trend always moves in the other direction. Markets go up, jobs get created, growth surges ahead. That's the American reality, seemingly as reliable as the sunrise. We not only expect it. We feel it's bound to happen. Whether or not it's true, our faith leads us to act as if it were, which more often than not helps to ensure that it does. We're a high risk, high reward society. And it's worked well for us for a long time. (Webmaster's comment: But not for all the innocent people we kill!)

4-27-20 Research volunteers won't be told of their coronavirus genetic risk
Half a million people who have volunteered their genetic information for scientific research will not be informed if researchers discover that they are genetically vulnerable to the coronavirus. The UK Biobank has been collecting this information, along with other health data, for over a decade, to create a widely-used database. Now, the hospital data of participants who have received a test for covid-19 or died as a result of the coronavirus will be added to the dataset. The hope is that researchers will be able to identify specific genetic factors that increase the likelihood of someone being badly sickened by the virus, but UK Biobank says that individuals will not be told about their personal risk. Participants explicitly consent to not receiving personalised health feedback when they sign up, says UK Biobank communications director Andrew Trehearne. People join with the understanding that the Biobank helps to improve the health of the population as a whole, rather than specific individuals, he says. Timothy Caulfield at the University of Alberta, points out that the UK Biobank has previously told volunteers about personal health findings, such as abnormalities on brain scans, though Trehearne says this only happens if a health worker is looking at a scan with a participant and notices something of potential concern. Still, Caulfield says UK Biobank should reconsider its disclosure policies in light of the pandemic. “Imagine if an individual or family got sick due to the nondisclosure of information.” Disclosing information to participants could reduce the burden on hospitals and save lives, says Andrea Boggio, a bioethicist at Bryant University in Rhode Island, but people shouldn’t be told without their consent. A better way of informing people would be to feed robust Biobank findings into the UK’s National Health System, so people could voluntarily contact their doctor if they want to know if they are at generally higher risk, says Boggio.

4-27-20 Deep caves are a rich source of dinosaur prints for this paleontologist
Several deep caves in France are proving to be a surprising source of ancient tracks. Crawling through tight underground passages in southern France, paleontologist Jean-David Moreau and his colleagues have to descend 500 meters below the surface to reach the only known footprints of long-necked dinosaurs called sauropods ever found in a natural cave. The team discovered the prints, left by behemoths related to Brachiosaurus, in Castelbouc Cave in December 2015 (SN: 2/21/18). But getting to the site might make even the most hardened field scientists balk. Wriggling through such dark, damp and cramped spaces every time they visit is challenging for elbows and knees, and even trickier when carrying delicate equipment such as cameras, lights and laser scanners. It’s both physically exhausting and “not comfortable for someone claustrophobic,” with the researchers spending up to 12 hours underground each time, says Moreau, of the Université Bourgogne Franche-Comté in Dijon. It can be dangerous too, as some parts of the cave are periodically flooded, so accessing the deep chambers must be limited to periods of drought, he says. Moreau has studied fossilized dinosaur footprints and plants for more than a decade in southern France’s Causses Basin, one of the richest areas for aboveground dinosaur tracks in Europe. When spelunkers chanced upon some underground prints in 2013, Moreau and his colleagues realized there could be lots of dinosaur prints within the region’s many deep, limestone caves. Footprints left in soft mud or sand hundred million years ago could have been turned to rock and forced underground over many eons. And deep caves, being less exposed to wind and rain, “can occasionally offer larger and better-preserved surfaces [imprinted by dinosaur steps] than outdoor outcrops,” Moreau says.

4-26-20 It’s time to stop debating how to teach kids to read and follow the evidence
Too many teachers are using the wrong approach. On a chilly Tuesday back in January, my 7-year-old son’s classroom in Minneapolis was humming with reading activities. At their desks, first- and second-graders wrote on worksheets, read independently and did phonics lessons on iPads. In the hallway, students took turns playing a dice game that challenged them to spell out words with a consonant-vowel-consonant structure, like wig or map. In another part of the classroom, small groups of two or three children, many missing their two front teeth, took turns sitting on a color-block carpet with teacher Patrice Pavek. In one group, Pavek asked students to read out loud from a list of words. “Con-fess,” said a dimpled 7-year-old named Hazel, who sat cross-legged in purple boots and a black fleece. Pavek reminded Hazel that a vowel sound in the middle of a word changes when you put an e at the end. Hazel tried again. “Con-fuse,” she said. “Beautiful!” Pavek beamed. When Hazel returned to her desk, I asked her what goes through her mind when she gets to a word she doesn’t know. “Sound it out,” she said. “Or go to the next word.” Her classmates offered other tips. Reilly, age 6, said it helps to practice and look at pictures. Seven-year-old Beatrix, who loves books about unicorns and dragons, advocated looking at both pictures and letters. It feels weird when you don’t know a word, she said, because it seems like everyone else knows it. But learning to read is kind of fun, she added. “You can figure out a word you didn’t know before.” Like the majority of schools in the United States, my son’s district uses an approach to reading instruction called balanced literacy. And that puts him and his classmates in the middle of a long-standing debate about how best to teach children to read.

4-25-20 What is a cytokine storm?
As COVID-19 cases fill the hospitals, among the sickest and most likely to die are those whose bodies react in a signature, catastrophic way. Immune cells flood and attack the lungs they should be protecting. Blood vessels leak; the blood itself clots. Blood pressure plummets and organs start to fail. Such cases, doctors and scientists increasingly believe, are due to an immune system gone overboard — so that it harms instead of helps. Normally, when the human body encounters a germ, the immune system attacks the invader and then stands down. But sometimes, that orderly army of cells wielding molecular weapons gets out of control, morphing from obedient soldiers into an unruly, torch- and pitchfork-bearing mob. Though there are tests and treatments that could help to identify and tamp down this insurrection, it's too early to be sure of the best course of therapy for those who are suffering a storm due to COVID-19. Variants on this hyperactive immune reaction occur in an array of conditions, triggered by infection, faulty genes, or autoimmune disorders in which the body thinks its own tissues are invaders. All fall under the umbrella term "cytokine storm," named because substances called cytokines rampage through the bloodstream. These small proteins — there are dozens — are the immune army's messengers, transiting between cells with a variety of effects: Some ask for more immune activity; some request less. When the cytokines that raise immune activity become too abundant, the immune system may not be able to stop itself. Immune cells spread beyond infected body parts and start attacking healthy tissues, gobbling up red and white blood cells and damaging the liver. Blood vessel walls open up to let immune cells into surrounding tissues, but the vessels get so leaky that the lungs may fill with fluid, and blood pressure drops. Blood clots throughout the body, further choking blood flow. When organs don't get enough blood, a person can go into shock, risking permanent organ damage or death. Most patients experiencing a storm will have a fever, and about half will have some sort of nervous system symptoms, such as headache, seizures, or even coma, says Randy Cron, a pediatric rheumatologist and immunologist at the University of Alabama at Birmingham and co-editor of the 2019 textbook Cytokine Storm Syndrome. "They tend to be sicker than you expect," he says. Doctors are only now coming to understand cytokine storms and how to treat them, he adds. Though there's no fail-safe diagnostic test, there are signs that a storm may be underway. For example, blood levels of the protein ferritin may rise, as may blood concentrations of the inflammation indicator C-reactive protein, which is made by the liver. The first hints that severe COVID-19 cases included a cytokine storm came out of Chinese hospitals near the outbreak's epicenter. Physicians in Wuhan, in a study of 29 patients, reported that higher levels of the cytokines IL-2R and IL-6 were found in more severe COVID-19 infections. IL-6 was also an early indicator of a cytokine storm-like condition in an 11-patient analysis by physicians in Guangdong. Another team, analyzing 150 cases in Wuhan, found that an array of molecular indicators for a cytokine storm — including IL-6, CRP, and ferritin — were higher in those who died than in those who survived. And immunologists in Hefei reported similar results among patients who died, as well as high levels of active, damaging immune cells spewing dangerous cytokines in the blood of COVID-19 patients who required intensive care. Cytokine storms are also raging among U.S. patients. "I've seen plenty of it," says Roberto Caricchio, chief of rheumatology at Temple University in Philadelphia. Precise data aren't in yet, but he says that a "sizable fraction" — perhaps 20 to 30 percent — of patients with severe cases and lung symptoms have signs of a cytokine storm.

4-24-20 Covid-19 news: US not involved in global WHO plan to tackle pandemic
The latest coronavirus news updated every day including coronavirus cases, the latest news, features and interviews from New Scientist and essential information about the covid-19 pandemic. Global leaders are launching an initiative with the World Health Organization (WHO) to accelerate the development of coronavirus drugs, tests and vaccines and ensure equal access to all countries, but the US is not involved. (Webmaster's comment: They do not need us, but we sure need them. We have MANY more cases and deaths than anybody!) European Commission president Ursula von der Leyen, French president Emmanuel Macron and German chancellor Angela Merkel were among leaders participating in a video conference to announce the plan. US president Donald Trump recently criticised the WHO’s handling of the pandemic and announced a withdrawal of US funding to the organisation. “The world needs these tools and needs them fast,” WHO director general Tedros Adhanom Ghebreyesus told the group. “We are facing a common threat which we can only defeat with a common approach,” he said. The company that owns Dettol and Lysol has issued a strong warning not to inject or ingest its products under any circumstance after Donald Trump falsely suggested disinfectants could be used as a treatment for coronavirus. Disinfectants are hazardous substances, which can be poisonous if ingested. The US state of Georgia has controversially re-opened hair salons, gyms and other non-essential businesses, even as coronavirus deaths continue to rise. A new website for essential workers in the UK to book coronavirus tests reached capacity and was temporarily closed within hours of being opened by the government. The Czech Republic has re-opened its borders for outbound travel after official figures showed a decline in the rate of confirmed covid-19 cases. The country was among the first in the Schengen area to close its borders on 16 March.

4-24-20 Pet food can contain drug-resistant bacteria that may pass to humans
Pet dogs and cats could be passing on potentially deadly antibiotic-resistant bacteria to their owners. Separate studies in Germany and Portugal have found that some pets harbour microbes that can withstand important antibiotics, including one used as a last resort. Other work suggests resistant bacteria are found in pet food, especially the increasingly popular raw food products. One of the new studies analysed raw, tinned and dry dog food brands sold commercially in Europe. Although some live gut bacteria were present in all three types, raw food had by far the highest level of microbes resistant to multiple antibiotics. Such bacteria were in all nine samples of raw food, one out of 22 of the tinned samples and in none of the 15 dry foods. “The main risk is that these bacteria can be a reservoir in pets’ and humans’ gut of resistance genes able to be transferred to other [disease-causing] bacteria,” says Ana Freitas at the University of Porto in Portugal, who was involved in the study. Two new studies of faecal samples taken from pets and their owners suggests transfer to humans may sometimes happen, although neither yet has data on whether the animals were given raw or cooked food. In work by Carolin Hackmann at the Charité – University Hospital Berlin, Germany, and her colleagues, 23 out of 45 dogs studied carried antibiotic-resistant bacteria, as well as one out of 71 cats. In two dogs, the microbes matched strains of bacteria found in their owners’ stool samples. This small number suggests pets aren’t a major source of drug-resistant microbes in their owners, says Hackmann. In a Portuguese study, two out of 55 dogs had gut microbes with resistance to the last-resort antibiotic colistin, which could be needed to treat bacterial pneumonia in intensive care. One dog shared this strain with its owner – although without further genetic analysis, it is unknown which direction the microbe had travelled.

4-24-20 Drugs for high blood pressure don’t appear to make COVID-19 worse
Two observational studies provide some reassurance for patients taking the drugs. Drugs widely used to treat high blood pressure do not appear to make COVID-19 dangerously worse. Two new studies from China offer the first observational evidence that the drugs do not increase the risk that hospitalized patients with COVID-19 will develop severe complications or die. One study looked at 362 patients with high blood pressure treated at Central Hospital of Wuhan, the city where the initial outbreak occurred. It found no difference between those on the drugs and those not in terms of the severity of the disease and whether a patient survived or died, researchers from the hospital report online April 23 in JAMA Cardiology. The other study followed 1,128 COVID-19 patients with hypertension from nine hospitals in Hubei Provence, where Wuhan is located. It found that the mortality rate was lower for the 188 on the drugs, an international research team reports online April 17 in Circulation Research. patients with COVID-19, as some had suspected,” says cardiologist Scott Solomon of Brigham and Women’s Hospital and Harvard Medical School in Boston. But without randomized controlled trials, in which patients are randomly chosen to take a drug or a placebo, “it will be very difficult to get at the truth” of exactly what impact the drugs have, he says. The drugs — angiotensin converting enzyme inhibitors, or ACE inhibitors, and angiotensin receptor blockers, or ARBs — have been in the spotlight since data emerged that COVID-19 takes a harder toll on people with hypertension, cardiovascular disease and diabetes (SN: 3/20/20). Many with these conditions take the drugs, which work to stop a hormone called angiotensin II from increasing blood pressure in the arteries.

4-24-20 Can virtual therapy help us cope with the coronavirus lockdown?
The coronavirus pandemic is likely to be bad for our mental health, as many people are now experiencing the effects of social isolation, financial distress and the potential loss of loved ones. Virtual sessions and mental health apps, whether they offer one-on-one therapy or simply mindfulness training, have been touted as a potential solution. Even before the pandemic, access to therapy could be limited and costly, despite one in four of us being expected to experience issues with our mental health at some point in our lives. As a result, these apps have been on the rise – last year, one called Calm became the first to be valued at over $1 billion. “Mental health apps seemingly have a lot of advantages: a greater reach of isolated populations, flexible treatment access, increased convenience, fewer visits to specialised clinics, and for some people they can afford greater anonymity and privacy,” says Rebecca Grist at the University of Brighton, UK. For those who were already in therapy, virtual therapy has been a lifeline during the pandemic. Anna*, a first-year nurse at King’s College London, has been continuing her university therapy sessions over the phone. “I liked that my therapist didn’t just drop me, and I was able to continue with it,” she says. In the US, regulations on whether a therapist could prescribe controlled substances remotely have been loosened during the crisis. “Virtual therapy has really exceeded people’s expectations in the last few weeks,” says John Torous at Harvard Medical School. Talking to your therapist from the comfort of your own home has suddenly been normalised, he says. But there are still challenges to virtual therapy. “Talking over the phone hasn’t been as conversational as talking in person so far,” says Anna. “I feel like it’s easier for you to hide your emotions on the phone, and it might hinder your therapy.”

4-24-20 The first frog fossil from Antarctica has been found
An ancient amphibian sheds light on when the continent iced over. The first fossil of a frog found in Antarctica gives new insight into the continent’s ancient climate. Paleontologists uncovered fragments of the frog’s hip bone and skull in 40-million-year-old sediment collected from Seymour Island, near the tip of the Antarctic Peninsula. Scientists have previously found evidence of giant amphibians that walked Antarctica during the Triassic Period, over 200 million years ago, but no traces on the continent of amphibians like those around today (SN: 3/23/15). The shape of the newly discovered bones indicates that this frog belonged to the family of Calyptocephalellidae, or helmeted frogs, found today in South America. The fossilized frog’s modern relatives live exclusively in the warm, humid central Chilean Andes. This suggests that similar climate conditions existed on Antarctica around 40 million years ago, researchers report April 23 in Scientific Reports. That offers a clue about how fast Antarctica switched from balmy to bitter cold (SN: 4/1/20). Antarctica quickly froze over after splitting from Australia and South America, which were once all part of the supercontinent Gondwana (SN: 10/10/19). But some geologic evidence suggests that ice sheets began forming on Antarctica before it fully separated from the other southern continents about 34 million years ago. “The question is now, how cold was it, and what was living on the continent when these ice sheets started to form?” says study coauthor Thomas Mörs, a paleontologist at the Swedish Museum of Natural History in Stockholm. “This frog is one more indication that in [that] time, at least around the Peninsula, it was still a suitable habitat for cold-blooded animals like reptiles and amphibians.”

4-23-20 Covid-19 news: Up to half of deaths in Europe have been in care homes
The latest coronavirus news updated every day including coronavirus cases, the latest news, features and interviews from New Scientist and essential information about the covid-19 pandemic. Up to half of those who have died from covid-19 in Europe were in care homes, according to Hans Kluge, the World Health Organization (WHO) regional director for Europe. Describing the finding as “deeply concerning”, Kluge said that many care homes may be “providing pathways for the virus to spread” and the problem has been made worse because care home workers are “overstretched, underpaid and unprotected.” Yesterday, the UK government’s chief medical adviser Chris Witty said it was hard to prevent deaths in care homes “sadly because this is a very vulnerable group.” Deaths due to malaria could double in sub-Saharan Africa this year compared to 2018, because of the impact of the coronavirus pandemic on access to mosquito nets and anti-malarial drugs. “Countries have a critical window of opportunity now to ensure malaria services are maintained even as the virus spreads,” said WHO director general, Tedros Adhanom Ghebreyesus. More than 15 per cent of the US workforce has now filed for unemployment benefits. An additional 4.4 million US citizens filed jobless claims in the last week, bringing the total since mid-March to 26.4 million. The US house of representatives will vote today on an additional $480 billion coronavirus relief package for small businesses and hospitals. The UK’s budget deficit is expected to see “an absolutely colossal increase to a level not seen in peacetime,” according to Paul Johnson, the director of the Institute for Fiscal Studies think tank. The deficit is expected to reach as high as £260 billion, he said. German chancellor Angela Merkel has said Germany is ready to make “significantly higher” EU budget contributions to help member states cope with the impact of the coronavirus pandemic. EU leaders are expected to sign off a new €540 billion emergency fund for the most severely affected countries but details are yet to be finalised. China has pledged to donate an additional $30 million to the WHO to help support the global fight against the covid-19, according to a spokesperson from the Chinese Foreign Ministry.

4-23-20 Brain implant lets man with paralysis move and feel with his hand
A brain implant has restored movement and a sense of touch in the hand of a man with a severe spinal cord injury. Patrick Ganzer at Battelle Memorial Institute in the US and his colleagues have developed a brain-computer interface (BCI) that has allowed 28-year-old Ian Burkhart to grasp and feel objects again. Burkhart has a severe upper spinal cord injury and has complete paralysis in his hands and legs, but can move his elbows and shoulders. He had a brain implant inserted in 2014 as part of research aiming to restore movement in his right arm. The BCI uses the implant to record brain activity that is sent to a processor that decodes these signals into movements, which in turn feed in to bands around the forearm which electrically activate his hand muscles. “We’ve made a lot of progress in the last six years: he can play [the video game] Guitar Hero, swipe a credit card and do about 20 different hand grips,” says Ganzer. But because Burkhart had no sensation in his hands, he previously had no sense of touch or pressure when grasping objects, and if blindfolded, was not able to detect small objects such as a pencil. The researchers discovered that although Burkhart’s hand cannot feel anything, the brain implant stills registers a faint sensory signal when he touches an object. They boosted this signal by incorporating a band around the bicep which vibrates when Burkhart’s hand receives sensory information. As a result, Burkhart is able to detect objects by touch alone. The BCI is also able to detect different levels of touch and adjust the strength of Burkhart’s hand movements depending on the object – a light grasp, for example, for a paper cup.The researchers believe it is the first BCI that can simultaneously restore movement and touch.

4-23-20 Coronavirus: Health claims debunked
5G does not spread Covid-19, steam inhalation is not a cure and skin colour can't protect from catching the virus. Reality Check's Chris Morris tackles the latest false claims about coronavirus circulating online.

4-23-20 COVID-19 kills more men than women. The immune system may be why
Biological differences in how the immune system operates could help explain the mortality bias. With more men than women developing severe illness and dying from COVID-19, sex differences that influence the immune system may offer answers. The bias in COVID-19 deaths appeared in the first reports out of China and has also been revealed in countries that break down their mortality data by sex. Of Italy’s 21,551 deaths recorded as of April 20, 64 percent were men. In Spain, 59 percent of the 12,634 deaths as of April 21 occurred in men. Germany had recorded 4,598 deaths by April 21, with 58 percent in men. The United States does not separate out national COVID-19 mortality by sex, but some states do. New York has the highest number COVID-19 deaths in the country, and as of April 21, 60 percent of 15,302 deaths were in men. Some of that discrepancy could be because men are more likely than women to have other health problems, such as hypertension and diabetes. These are among the underlying conditions that raise the risk for severe COVID-19 disease, the U.S. Centers for Disease Control and Prevention reported April 3. Another possible culprit is the immune system itself. The many proteins that work together to defend the body against viruses do not operate exactly the same way in males and females. Those biological differences, driven by sex hormones and genes, may be guarding some women from the deadliest complications of COVID-19. In general, females mount a stronger immune response than males, studies have found. This makes women overall less susceptible to viral infections than men, although how each individual fares is another matter. A stronger immune response also means females are more likely to develop autoimmune diseases, when the immune system attacks one’s own tissue; conversely, a toned down immune response makes males more prone to having a host of malignant cancers.

4-23-20 COVID-19 is hitting some patients with obesity particularly hard
Emerging data show BMI plays a role in who needs intensive care and who survives. As part of the COVID-19 response team at O’Connor Hospital in San Jose, Calif., Nivedita Lakhera wasn’t prepared to see her intensive care unit filled with so many young patients. Many of those patients had no medical condition other than obesity. “They are young and coming to the ER and just dropping dead,” she says. Age, particularly those over 65, as well as having a compromised immune system are still major risk factors for being hospitalized with, and dying from, COVID-19. But some doctors say that some of their sickest patients are those under 60 who are obese. The Centers for Disease Control and Prevention’s list of high-risk individuals includes the severely obese, defined as people with a body mass index, or BMI, over 40. While studies on coronavirus often focus on demographic breakdowns such as age, sex and race (SN: 4/10/20), some now are starting to track COVID-19 patient BMIs. For instance, of 180 patients hospitalized from March 1 to March 30, the most prevalent underlying condition for adults ages 18 to 49 was obesity. Of 39 patients in that age range, 23, or 59 percent, were obese, researchers report in the April 17 Morbidity and Mortality Weekly Report. “BMI is the Achilles’ heel for American patients,” says Jennifer Lighter, an epidemiologist at New York University’s Langone School of Medicine. That could be a crucial factor in the death toll, particularly for those under 60, she says. “In China it was smoking and pollution, and Italy had a larger older population, and many grandparents lived with extended families. Here, it’s BMI that’s the issue.” In the United States, 42 percent of adults have a BMI over 30, the threshold for obesity, and more than 9 percent are classified as severely obese with a BMI over 40, according to the CDC. People with obesity can have other high-risk health conditions, such as hypertension or diabetes (SN: 3/20/20). But some doctors suggest a high BMI should be a risk factor in itself.

4-23-20 BCG vaccine being trialled as potential protection against covid-19
As scientists race to make a new vaccine against covid-19, some are touting a century-old one as a possible stopgap. The vaccine is BCG (Baccillus Calmette-Guérin), which protects against tuberculosis (TB). In countries with routine BCG vaccination, the pandemic appears to be less severe. Advocates of BCG say this could be because the vaccine is a general immune-system enhancer – a long-standing but unproven hypothesis. But critics say we can’t be sure. BCG has been used since 1921. It contains a live bacterium related to the one that causes TB, and the World Health Organization recommends it in countries with high levels of the disease. Most countries – including China, where the coronavirus outbreak began – have a national programme. But some, including the US and Italy, have never had one and others phased it out as TB became less of a concern – the UK stopped in 2005. The vaccine was already being updated but the epidemic has given it a booster shot. In March, the Max Planck Institute for Infection Biology in Berlin announced plans for a clinical trial of a genetically-modified version of BCG, VPM1002, against the covid-19 coronavirus. Its rationale was that the vaccine has been shown to make mice more resistant to viruses including flu and herpes. The trial has been given regulatory approval and should start before the end of the month. If it succeeds, millions of doses could be made available in a very short time, says Adar Poonawalla of the Serum Institute of India, a private company that is partnering with the Max Planck to develop the vaccine. A second clinical trial has already begun in the Netherlands, which will test whether the vaccine reduces absenteeism among healthcare workers for any reason including illness. The Netherlands does not vaccinate with BCG so most healthcare workers will never have had it. The trial is due to be completed in December. A third trial is underway in Australia, with preliminary results due in October, though the full trial will run until March 2022.

4-22-20 Smartphone-powered device tests blood samples for genetic conditions
It is now possible to use a cheap, lightweight and smartphone-powered DNA detector to identify DNA in blood, urine and other samples, on the spot. At the moment, testing to identify DNA is done in laboratories using expensive, specialised equipment. To make this process faster and cheaper, Ming Chen at the Army Medical University in China and his colleagues developed a portable DNA detector made of 3D-printed parts that attach to a standard smartphone. The device can detect DNA based on characteristic mutations or short genetic sequences. It costs less than $10 to make, weighs just 60 grams, and takes 80 minutes to produce a result. The detector is powered by heat from the smartphone. Samples can be loaded into the detector and mixed with pre-filled chemicals that light up or change colour if there is any DNA that matches. The signals are detected through the smartphone’s camera lens and a light box displays the result. Tests showed that the device can detect genetic conditions like alpha- and beta-thalassemia in blood. It also identified people with a gene that makes them more susceptible to alcohol intoxication from swab samples taken from their inner cheeks. It identified E. coli bacteria in urine, milk and river water. It also identified a bacterium that attacks kiwi fruit plants in ground-up samples of the plant’s leaves. Overall, the accuracy of the device was about 97 per cent when compared with standard laboratory methods. The researchers say the device could potentially be modified to identify RNA as well, which would be useful for detecting RNA viruses like the covid-19 virus responsible for the coronavirus pandemic. Jacqueline Savard at Deakin University in Australia says the technology has the potential to cause unintended consequences if used outside normal clinical settings, because people wouldn’t have access to support and guidance if they test positive for an illness.

4-22-20 7 mental health expert tips on how to cope with the covid-19 pandemic
Whether you are at home alone or juggling work and family, those working in mental health share their advice on how to cope with the covid-19 pandemic. Advice from the experts:

  1. Maintain regular rhythms: wake up, eat and go to sleep at the same time you normally would. Find a project to keep yourself going, whether that’s work, learning something new or reading Proust. Maintain connections with others by phone or online, and exercise once a day, preferably in green space, and always while social distancing.
  2. Limit your exposure to media stories about the pandemic – especially those with experts’ views about what is going to happen over the next three months – because it can cause anxiety.
  3. Think about the things you have done in the past that have helped you to feel a sense of calm and stability. For me, it’s reading. That is something I have always enjoyed, that I haven’t often had time to do and I’m able to make space for now – in the silence of being at home.
  4. Whenever you’re on social media, think of your own and others’ mental health. Think about why and how you’re using it. Is it benefiting you, someone else or is it just mindless scrolling? Be analytical and only share something when you’ve verified the source. Sharing fake news is so disturbing, it has a negative impact on all of us, especially on those with mental health problems.
  5. Remember that whatever you put into the atmosphere, you tend to get back – you have some control over that. At home, work as a team with your partner. Plan how you will use the rooms, when you will be together and when you will have your private space. Negotiating this can help you and your partner to feel cared for.
  6. It is important to be honest and acknowledge your emotions, and it’s important for parents to be open and honest with their children. What isn’t helpful is panic. Be factual, explain what the risk is, and what can be done to reduce it. Be responsive – answer questions when they’re asked, and use words and ideas that your children can understand. Parents are good at this, because they have lots of practice.
  7. Allow the chaos for a bit and then start to develop a structure in the home, so that the children feel sane and safe, and the parents feel sane and safe. Understand that this structure will be organic, which is a polite way of saying that it is likely to go tits up at some point. And go easy on yourself: this pandemic is unprecedented. The prime minister didn’t get this right straight away, and neither will we.

4-22-20 The past can help us deal with the pandemic’s mental health fallout.
Lessons learned from natural disasters and the military can help guide our responses to help people's mental health during the covid-19 pandemic. THERE are still many unknowns about how this pandemic will play out. The immediate concern is rightly how to save lives. But another important question is the effect on the world’s long-term mental health. The future here is unclear and an ongoing global research effort to monitor and understand the mental toll is needed. Psychologists are already tooling up to find answers. In the meantime, one useful way to break down the problem is to examine the impacts on four groups, as we write in our special report (see “How to protect your mental health in the time of coronavirus”). These are the general population, families and children, vulnerable people and front-line workers. Past experiences of national trauma can be our guide and allow us to draw several ideas. First, the good news: many of the potential negative consequences to our mental health can be avoided if we take good and timely action. Past experience also suggests that some groups will be hit harder. Existing mental health inequalities within society will widen, compounded by the financial insecurity brought on by the pandemic, which, as we saw after Hurricane Katrina in 2005, can exacerbate mental health issues. Those with pre-existing mental health problems are particularly vulnerable at a time when they are unlikely to have access to their normal means of support. For them, advice isn’t enough – they must have access to professional psychological help, and we need more ways to deliver this remotely. Experience within the military can offer useful coping strategies for front-line healthcare workers. Team leaders must be primed to identify signs among staff that normal levels of distress are turning into something more serious. Simple actions, such as a short conversation during times of acute stress, can improve long-term mental health outcomes.

4-22-20 More evidence hints that hydroxychloroquine doesn’t help treat COVID-19
So far, a malaria drug isn’t living up to the hype. The malaria drug hydroxychloroquine has been touted by some, including President Trump, as nearly a miracle cure for COVID-19. But new preliminary evidence suggests that coronavirus patients fare no better on the drug than they do with standard care. Researchers in Iran examined six studies, including small studies from France and China, that had suggested the drug might slightly shorten recovery time. All six studies compared hydroxychloroquine with standard care, which may include monitoring, fluids, oxygen and other supportive care as needed. Across all studies, there were no statistically relevant differences in the outcomes of patients who took hydroxychloroquine and those who didn’t, the scientists report April 20 at medRxiv.org. Slightly more people taking the drug showed clearer lungs compared with those on standard treatment. And after taking the drug, the virus’s genetic material was also detectable in slightly fewer people than those who didn’t take the drug. But there were also more mild side effects, such as rashes and headaches, in the group taking hydroxychloroquine. The researchers caution that there were too few patients in the studies to make a definitive conclusion about whether the drug works. Meanwhile, researchers in South Carolina and Virginia examined records from 368 male patients with COVID-19 admitted to U.S. Veterans Health Administration medical centers from March 9 through April 11. That retrospective study also showed no benefit to taking hydroxychloroquine alone or in combination with azithromycin to treat the disease versus standard care, the team reports April 21 at medRxiv.org. Azithromycin is antibiotic that also works to dampen inflammation. Some studies are testing it in combination with hydroxychloroquine.

4-22-20 How to protect your mental health in the time of coronavirus
From social isolation to working on the front line, the mental health challenges of the pandemic are wide reaching. We ask experts how to protect ourselves. AFTER weeks of complete social isolation, Italy has undergone what psychiatrist Paolo Brambilla calls “a social experiment that has never been done before”. The country has suffered a massive death toll from the coronavirus, and has endured one of the strictest lockdowns in the world. The effects on the nation’s psyche will be profound, says Brambilla, who is at the University of Milan. This month saw half of the world’s population enter some form of confinement, and many people are facing the biggest threat to their health and livelihood in recent history. “We are seeing the spread of a virus, but we have also, from the very beginning, been seeing the spread of fear as well,” says Aiysha Malik, a psychologist at the World Health Organization. As well as having to wrap our heads around the threat of the virus itself, public and personal life has changed beyond recognition. The actions we have had to take to curb the spread of disease have left some of us struggling to cope with a lack of childcare while working, a loss of income, separation from family and friends, and serious health fears. For others, it has meant working on the front line, facing potentially traumatic experiences and making tough moral decisions. Whatever our situation, it’s time to look at what we can all do to limit the toll on our mental well-being. “People are facing a novel, threatening and unpredictable experience,” says psychiatrist Andrea Danese at King’s College London. “At the same time, people are losing important coping strategies for stressful situations, enduring disruption in their routine and having to distance themselves from friends and families. They may also suffer the losses of loved ones. It is important to consider the longer-term implications of this emergency for mental health.” In a survey published last week in The Lancet Psychiatry, people in the UK reported increased anxiety, depression and stress, and concerns about social isolation. These were larger worries than the prospect of having covid-19.

4-22-20 Some babies who were born prematurely have weaker hearts as adults
People who were born prematurely may have weaker hearts that recover less well after exercise, a study has found. This may help explain the increased incidence of cardiovascular disease among prematurely born individuals. “The most likely explanation is the disruption to normal development, as pre-term birth occurs under a key developmental window for the heart and vascular system that would normally occur inside the womb during the third trimester,” says Adam Lewandowski at the University of Oxford. He and his team studied 47 adults aged 18 to 40 who were born moderately prematurely – at between 32 and 36 weeks of pregnancy, the period in which 84 per cent of prematurely born babies are delivered – and 54 who were born at term, approximately 40 weeks. They measured the participants’ heart and lung function before, during and after intense exercise on a cycling machine. Peak oxygen uptake during exercise – a key indicator of heart and lung capacity – was decreased by 16 per cent on average in the pre-term individuals, compared with those who were born at term. Two minutes after peak exercise, heart rates had recovered by 19 per cent more in the group of people born at term than the pre-term group. These two factors, a reduced oxygen uptake and slower heart rate recovery, are both risk factors for cardiovascular disease, says Lewandowski. This study adds to emerging evidence indicating that pre-term birth leads to long-term vulnerability to heart disease, says Mary Jane Black at Monash University in Australia, “This will help to get the message out to clinicians that the hearts of adult individuals [born pre-term] – even those born only a few weeks early – are abnormal when compared with the hearts of term-born individuals,” she says.

4-22-20 Not getting enough sleep may make you misread emotions on Zoom calls
Getting less sleep for five nights in a row can make you view other people’s expressions more negatively, including facial reactions seen over video calls. IF YOU have five consecutive nights of restricted sleep, it will not only leave you sleepy and grumpy, it may also make you view other people’s reactions more negatively. We know that sleep deprivation can affect the way a person thinks and functions. But sleep restriction, in which a person gets less sleep than is normal for them, is far more common. To find out how it might affect our cognition, Daniela Tempesta at the University of L’Aquila in Italy and her colleagues asked 42 volunteers to restrict how much sleep they got for five days. First, each participant wore a device on their wrist that tracked their normal sleep for five consecutive nights, during which they typically slept for around 7 to 8 hours a night. The volunteers filled out questionnaires to assess their mood, sleepiness, energy and concentration. They then looked at a series of cartoon images of people expressing a range of emotions and scored them on a scale of one to nine, based on how positive or negative they thought the image was. The following week, the volunteers were told to stay awake until 2 am, then go to sleep and wake up at 7 am. Tempesta and her colleagues confirmed when the participants were asleep and awake by checking data from the wrist devices and called the participants if they failed to wake up at the designated time. At the end of the five days of restricted sleep, the volunteers repeated the questionnaires and image scoring tasks. Unsurprisingly, these indicated that they were more tired and sleepy after the restricted sleep. They were also less alert, and in a more negative mood (Journal of Sleep Research, doi.org/dr7b).

4-22-20 AI can distinguish between bots and humans based on Twitter activity
Artificial intelligence is being used to spot the difference between human users and fake accounts on Twitter. Emilio Ferrara at the University of Southern California and his colleagues have trained an AI to detect bots on Twitter based on differences in patterns of activity between real and fake accounts. The team analysed two separate data sets of Twitter users, which had been classified either manually or by a pre-existing algorithm as either bot or human. The manually verified data set consisted of 8.4 million tweets from 3500 human accounts, and 3.4 million tweets from 5000 bots. The researchers found that human users replied between four and five times more often to other tweets than bots did. Real users gradually become more interactive, with the fraction of replies increasing over the course of an hour-long session of Twitter use. The length of tweets by human users also decreased as sessions progressed. “The amount of information that is exchanged diminishes,” says Ferrara. He believes that the change may result from a cognitive depletion over time, in which people become less likely to expend mental effort composing original content. Bots, on the other hand, show no changes in their interactivity or the length of information they tweet over time. The team also analysed the amount of time between any two consecutive tweets from a single user. When this distribution is plotted, bots showed spikes for certain time gaps, such as tweeting at 30-minute or 60-minute intervals. The team then combined these measures to train an existing bot-detection algorithm, called Botometer, on the difference in activity patterns. The AI was significantly more likely to accurately detect to fake accounts than when it was not taking into account the timing of posts.

4-22-20 ‘The Idea of the Brain’ explores the evolution of neuroscience
Despite advances, much about the human brain is still a mystery. Neuroscientists love a good metaphor. Through the years, plumbing, telegraph wires and computers have all been enlisted to help explain how the brain operates, neurobiologist and historian Matthew Cobb writes in The Idea of the Brain. And like any metaphor, those approximations all fall short. Cobb leads a fascinating tour of how concepts of the brain have morphed over time. His writing is clear, thoughtful and, when called for, funny. He describes experiments by neurosurgeon Wilder Penfield, who zapped awake patients’ brains with electricity to provoke reactions. Zapping certain places consistently dredged up memories, which Cobb calls “oneiric experiences.” His footnote on the term: “Look it up. It’s exactly the right word.” I did, and it was. Cobb runs though the history of certain concepts used to explain how the brain works, including electricity, evolution and neurons. Next comes a section on the present, which includes discussions of memory, circuits and consciousness. Cobb offers tastes of the latest research, and a heavy dose of realism. Memory studies have made progress, but “we are still far from understanding what is happening when we remember,” Cobb writes. Despite big efforts, “we still only dimly understand what is going on when we see.” Our understanding of how antidepressants work? “Virtually non-existent.” This real talk is refreshing, and Cobb uses it to great effect to argue that neuroscience is stymied. “There have been many similar moments in the past, when brain researchers became uncertain about how to proceed,” he writes. Scientists have amassed an impressive stockpile of brain facts, but a true understanding of how the brain works eludes us.

4-21-20 Toddlers born with Zika virus seem to be affected in multiple ways
When Zika virus first hit Brazil five years ago, the impact was devastating. Cases of infection with the virus began to be detected in adults in Brazil in early 2015, and then began spreading across the Americas. But it wasn’t until the second half of 2016 that paediatricians started to see an increase in cases of microcephaly, a condition in which babies are born with a small head and sometimes brain damage, in newborns. That year, researchers confirmed that infection with Zika during pregnancy can cause lasting brain damage in some fetuses, which can lead to arrested brain development in babies. Some babies didn’t survive. Those that did are now around 4 years old. Neurologists are now learning that congenital Zika syndrome – the name of the condition the virus causes in children who were infected as fetuses – can be divided into at least two groups, based on the children’s symptoms. This could help determine which therapies may be potentially helpful for those affected. “Zika really was a disaster here in Brazil,” says Heloisa Pereira, a paediatric neurologist at Rio de Janeiro State University. “We knew nothing about the disease.” One 2019 study of Brazilian national health records found that of more than 6.8 million births in the country between 1 January 2015 and 23 May 2017, nearly 2,800 babies were born with microcephaly and structural brain damage. Forty-one in every 10,000 women who were infected with Zika virus in the first trimester, and 17 women in every 10,000 infected in the second trimester, gave birth to a baby with microcephaly. Along with her colleagues, Pereira has been studying a group of 75 children in Campina Grande, Paraíba, in north-east Brazil. Brain scans of the children show that their brains have the hallmarks of congenital Zika syndrome. “Most of them were born with microcephaly. Most of them cannot speak and are completely dependent,” says Pereira.

4-21-20 Can parents still share custody during the pandemic?
Is it safe to keep co-parenting during coronavirus? hree months ago, my ex-husband and I had a (particularly ridiculous, with hindsight) fallout over our children's socks. Yes, socks. I buy them, he loses them. I was sick of sending our kids to him in matching pairs and then getting them back in mismatched ones, or without any socks at all. I nearly accused him of stockpiling socks under his bed as some sort of delayed revenge for me ending our relationship, but I resisted. What can I say — co-parenting with an ex can drive you to some crazy thoughts. Of course, with the coronavirus pandemic raging, socks are the least of my worries right now. What matters to me most is keeping my kids healthy — physically, mentally, and emotionally. Which is why, in the face of enormous uncertainty and widespread confusion and fear, my ex and I have decided to continue with our existing co-parenting plan: The children spend four nights a week with me and three with their dad. This might seem to COVID-19 purists to be a breach of strict stay-at-home orders, but many experts (and fellow parents) agree that for kids already splitting their time between parents, sticking with the co-parenting schedule is the right thing to do. "Keeping your parenting schedule at this time is critical," says licensed clinical psychologist and parenting evaluator Melanie English, Ph.D. "Routine and structure with school, friends, sports, and extracurricular activities has been halted. ... Children need the consistency and that will help them feel like part of their world is still safe and in control." One crucial qualifier in our coronavirus co-parenting arrangement: It is subject to change if any of us developed COVID-19 symptoms. So if I were to get sick while the kids were with me, for example, we'd all isolate in my home for at least 14 days. Of course, we're vigilant about social distancing and hygiene measures. The kids don't take anything between the two homes apart from the clothes on their backs and one device each. When they get back from their dad's place, their shoes go in a box at the door, their clothes go straight into the washing machine, and they wash their hands before they touch anything — door handles, their baby sister, me. Basically, we're following the rules while still letting our kids spend their usual amount of time with both parents. And there really wasn't much discussion about it. I know other parents are doing things a little differently. Some are keeping the kids with their primary carer and facilitating contact with the other parent through phone calls and FaceTime. But this just didn't feel right to us. We have something very close to a 50/50 arrangement, and I don't feel I have the right to call the shots just because I'm the mother. Even if I do buy all the socks. There's also the kids' emotional needs to consider. How might they respond to having their time with one parent suddenly limited? "When a young child doesn't see one parent for an extended period of time, they can develop feelings of abandonment or even develop pathological attachment styles that they carry into their adult relationships," says board certified psychiatrist Margaret Seide, MD.

4-20-20 Can breathing exercises really help protect you from covid-19?
Deep breaths and forced coughs might help clear mucus but are unlikely to help people with a dry cough and mild cases of covid-19 – contrary to much advice circulating on social media. Breathing exercises are an important part of managing some respiratory conditions, like chronic obstructive pulmonary disease. The main aims of such exercises are to clear the lungs of sticky mucus, coordinate your breathing with medication to deliver the optimal dose and to keep the airways open, says Michael Niederman at Weill Cornell Medicine in New York. These exercises often involve taking deep breaths and coughing up sputum, and doctors may recommend devices that vibrate the airways to help with this. Could such techniques help people who have covid-19? On the face of it, simple breathing exercises, such as those recommended by a UK doctor in a viral video shared widely on Twitter, make sense for people with covid-19, says Niederman. In the video, the doctor recommends taking a deep breath and holding it in before releasing it. The doctor suggests repeating this five times, before finishing a final round of breathing with a big cough. The exercise is similar to others used in respiratory care, says Niederman. Deep breaths are generally a good idea, because they can encourage air into the depths of the lungs. If these pockets of the lung aren’t used, they can essentially close, and become at risk of infection, says Niederman. Deep breaths can also increase the amount of oxygen getting into the body, and the volume of carbon dioxide leaving it, says Ema Swingwood, chair of the Association of Chartered Physiotherapists in Respiratory Care. Although deep breaths can be helpful, it isn’t generally a good idea to inhale through your mouth when taking them, as the doctor in the video does. Sucking in a big gulp of air can irritate an existing dry cough. Breathing in through your nose is a better idea, says Swingwood. “The nose warms and moistens the air that you take in,” she says. “Breathing in dry air isn’t going to help you.”

4-20-20 Coronavirus: Plasma treatment to be trialled
The UK is gearing up to use the blood of coronavirus survivors to treat hospital patients ill with the disease. NHS Blood and Transplant is asking some people who recovered from Covid-19 to donate blood so they can potentially assess the therapy in trials. The hope is that the antibodies they have built up will help to clear the virus in others. The US has already started a major project to study this, involving more than 1,500 hospitals. When a person has Covid-19, their immune system responds by creating antibodies, which attack the virus. Over time these build up and can be found in the plasma, the liquid portion of the blood. NHSBT is now approaching patients who have recovered from Covid-19 to see if plasma from them can be given to people who are currently ill with the virus. A statement from the organisation said: "We envisage that this will be initially used in trials as a possible treatment for Covid-19. "If fully approved, the trials will investigate whether convalescent plasma transfusions could improve a Covid-19 patient's speed of recovery and chances of survival. "All clinical trials have to follow a rigorous approval process to protect patients and to ensure robust results are generated. We are working closely with the government and all relevant bodies to move through the approvals process as quickly as possible." Several groups in the UK have been looking into using blood plasma. University Hospital of Wales (UHW) in Cardiff announced this week that it wanted to trial the technology. Professor Sir Robert Lechler, president of the Academy of Medical Sciences and executive director of King's Health Partners, which includes King's College London and three major London hospitals, is also hoping to set up another small-scale trial. He wants to use plasma for seriously ill patients that have no other treatment options, while a larger national trial is getting under way.

4-19-20 Coronavirus: Will Covid-19 speed up the use of robots to replace human workers?
As a pandemic grips the world, a person could be forgiven if they had forgotten about another threat to humanity's way of life - the rise of robots. For better or worse the robots are going to replace many humans in their jobs, analysts say, and the coronavirus outbreak is speeding up the process. "People usually say they want a human element to their interactions but Covid-19 has changed that," says Martin Ford, a futurist who has written about the ways robots will be integrated into the economy in the coming decades. "[Covid-19] is going to change consumer preference and really open up new opportunities for automation." Companies large and small are expanding how they use robots to increase social distancing and reduce the number of staff that have to physically come to work. Robots are also being used to perform roles workers cannot do at home. Walmart, America's biggest retailer, is using robots to scrub its floors. Robots in South Korea have been used to measure temperatures and distribute hand sanitiser. With health experts warning some social distancing measures may need to be in place through 2021, robot workers may be in greater demand. Companies that make cleaning and sanitising products have seen demand soar. UVD Robots, the Danish manufacture of ultraviolet-light-disinfection robots, shipped hundreds of its machines to hospitals in China and Europe. Groceries and restaurants offering takeaway are using these machines more too. Experts say as more businesses re-open we can expect to see further adoption of this technology - you may see robots cleaning your schools or offices. "Customers now care more about their safety and the safety and health of workers," says Blake Morgan, author of The Customer of the Future. "Moves towards automation can keep them all healthier and customers will reward companies that do this." There are still limitations. Ms Morgan points out that automated checkouts at groceries should reduce human interactions but because many systems don't work well or break easily customers avoid them and go to human cashiers instead.

4-18-20 Coronavirus: AI steps up in battle against Covid-19
It feels as if a superhuman effort is needed to help ease the global pandemic killing so many. Artificial intelligence may have been hyped - but when it comes to medicine, it already has a proven track record. So can machine learning rise to this challenge of finding a cure for this terrible disease? There is no shortage of companies trying to solve the dilemma. Oxford-based Exscientia, the first to put an AI-discovered drug into human trial, is trawling through 15,000 drugs held by the Scripps research institute, in California. And Healx, a Cambridge company set up by Viagra co-inventor Dr David Brown, has repurposed its AI system developed to find drugs for rare diseases. The system is divided into three parts that: 1. trawl through all the current literature relating to the disease. 2. study the DNA and structure of the virus. 3. consider the suitability of various drugs. Drug discovery has traditionally been slow. "I have been doing this for 45 years and I have got three drugs to market," Dr Brown told BBC News. But AI is proving much faster. "It has taken several weeks to gather all the data we need and we have even got new information in the last few days, so we are now at a critical mass," Dr Brown said. "The algorithms ran over Easter and we will have output for the three methods in the next seven days." Healx hopes to turn that information into a list of drug candidates by May and is already in talks with labs to take those predictions into clinical trials. For those working in the field of AI drug discovery, there are two options when it comes to coronavirus: 1. find an entirely new drug but wait a couple of years for it to be approved as safe for use. 2. repurpose existing drugs. But, Dr Brown said, it was extremely unlikely one single drug would be the answer. And for Healx, that means detailed analysis of the eight million possible pairs and 10.5 billion triple-drug combinations stemming from the 4,000 approved drugs on the market.

4-18-20 Ancient recipes led scientists to a long-lost natural blue
Medieval texts and modern techniques helped unveil the blue watercolor’s identity. Scientists have resurrected a purple-blue hue whose botanical origin had been lost to time. The pigment, called folium, graced the pages of medieval manuscripts. But it fell out of use, and the watercolor’s identity has eluded scientists for decades. Now, after tracking down folium’s source, researchers have mapped out the chemical structure for its blue-producing molecule. Such chemical information can be key to art conservation. “We want to mimic these ancient colors to know how to … preserve them,” says Maria Melo, a conservation scientist at Universidade Nova de Lisboa in Caparica, Portugal. But to unmask folium’s identity, Melo and her team first had to find where it came from. The researchers turned to medieval texts that described the source plant. With the help of a botanist, they discovered Chrozophora tinctoria, a tiny herb with silvery-green foliage. In a village in the south of Portugal, the team found the wild plant growing along the roadside and in fields after harvest. Back in the lab, researchers extracted the pigment from its pebble-sized fruits by following directions detailed in the medieval manuscripts. “It was really great fun to recover these recipes,” Melo says. The team used a suite of analytical techniques to zero in on the dye molecule’s structure, it reports April 17 in Science Advances. The scientists also simulated light’s interaction with the candidate molecule, to check whether it would give them their desired blue. Long-lasting blues are relatively rare among dyes, and this one is neither like the indigo (SN: 9/14/16) used in denim jeans nor an anthocyanin, such as those that show up in many flowers (SN: 7/26/17). This newfound hue is in its own class of blues.

4-17-20 There are many reasons why covid-19 contact-tracing apps may not work
As countries search for ways to exit lockdown and avoid or manage a second wave of covid-19 cases, many have turned to the promise held by contact-tracing apps. In a rare display of collaboration, Apple and Google recently joined forces to help the technology work effectively. Such apps look attractive to countries looking to lift restrictions, but there is growing evidence that it will be difficult to make them work. A simulation of a city of 1 million people by researchers at the University of Oxford, published yesterday, found that 80 per cent of smartphone users in the UK would need to install a contact-tracing app in order for it to be effective in suppressing an epidemic: that is 56 per cent of the national population. The UK’s chief scientific adviser, Patrick Vallance, has indicated that he thinks such apps might have a role to play in contact tracing but that it would be a tall order to get 80 per cent of smartphone owners in the UK to use them. That is a tough target for the UK’s NHSX, the National Health Service digital transformation unit, which is developing such an app. Surveys of 6000 potential app users in five countries suggest the level of take-up is unlikely to be this high. Results suggest that nearly 74 per cent of UK smartphone users would be willing to install a contact-tracing app, but the proportion who do it in reality could be much lower. In Singapore, only an estimated 17 per cent of the population installed a contact-tracing app launched last month. Even if app uptake is low, however, the University of Oxford team estimates that such technology could still cut cases and deaths. The principle behind contact-tracing apps is fairly simple. Once installed, they use Bluetooth low-energy (LE) technology to record when a phone has come into close proximity with anyone else using the app. If either person later reports coronavirus symptoms, the other party is notified, so they could self-isolate or seek health advice. An alert could also be sent if a medical authority certifies the other person tested positive for the virus – this would be one way to avoid users trolling the system by falsely claiming symptoms. In theory, the apps work anonymously and only store data temporarily, without collecting location.

4-17-20 End-of-life medical decisions being rushed through due to coronavirus
The coronavirus pandemic is forcing people to confront dilemmas around how much medical care should be given at the end of life. The emergency situation means doctors and patients are having to rush controversial decisions about turning down certain treatments, say palliative care experts. “The crisis has brought to the fore a lot of the problems with decision-making around the end of life which have been simmering for ages,” says Celia Kitzinger at Cardiff University in the UK. “Coronavirus has lit the fuse.” There has long been concern over whether some people receive excessive medical intervention at the end of their lives, when it merely prolongs the dying process. The best known such case is cardiopulmonary resuscitation (CPR), which is usually futile in those who are very old or sick. Now, attention is also falling on whether someone should get ventilation if their lungs are failing, especially as there may not be enough machines to go around. Ventilation can be distressing and has little chance of success in those who are very elderly or were in poor health beforehand. People need to think about whether they would want to go on a ventilator, or even if they would want to go to hospital at all, says Kitzinger. She says those in the UK should make an advance decision, a legally binding document about someone’s medical choices, or give a relative lasting power of attorney so they can make decisions on their behalf – although this process can take months. Kitzinger is a founder of Advance Decisions Assistance, a charity that helps people take these steps. In the UK, many family doctors are now phoning or sending letters to their patients who are elderly or have underlying health conditions to discuss opting out of CPR and other interventions. “People are essentially being cold-called to make really difficult decisions,” says Kathryn Mannix, a palliative care doctor in northeast England. However, even if someone says that they would want to receive CPR, doctors can legally still decline if they think it would be futile.

4-17-20 What would a game-changing treatment for coronavirus look like?
. We keep hearing claims that this or that drug will be a game changer in the coronavirus pandemic. So what would a treatment have to do to be a game changer? First, it needs to work. Most of the reported results from experiments that have been hurriedly set up in response to the covid-19 outbreak are either not from rigorous randomised controlled trials, or involve such small numbers that the results are far from conclusive. “No therapies have been shown [to be] effective to date,” concludes a review published on 13 April. It seems likely that at least a few of the many treatments being trialled will prove effective, but that doesn’t mean they will make a huge difference to the course of the pandemic. Doctors describe drugs as effective if they have an effect, but often the effect is small. A drug that reduces the number of seriously ill people dying by, say, 20 per cent would save many thousands, but it wouldn’t mean we could all resume normal lives. There is no formal definition of a “game changer”, but to me it would be something that transforms the wider situation. It might be, say, a drug that dramatically reduces the proportion of people admitted to hospital with covid-19 becoming so ill they require ventilation, greatly easing the burden on healthcare systems. Better yet would be a drug that stops almost all those infected becoming seriously ill in the first place. The criteria for such a treatment are very different to one given at a later stage, says Trudie Lang at the University of Oxford. An early treatment will have to be in pill form so people can take it at home, be very cheap so it can be dished out to millions, and be extremely safe because most people who take it would probably be fine without it, because they may never contract covid-19 or have anything more than mild symptoms if they do.

4-17-20 Why 6 feet may not be enough social distance to avoid COVID-19
The coronavirus can spread through the air and via asymptomatic people, affecting the equation. In February, a man in Chicago brought food to and hugged two friends who had recently lost a family member. The next day, the man went to the funeral, where he comforted other mourners and shared a potluck meal. A few days later, he attended a family birthday party. The man had symptoms of a mild respiratory illness. Later he’d learn he had COVID-19. His acts of condolence and celebration set off a chain reaction that sickened at least 16 people, three of whom died. At the time, social distancing measures weren’t yet in place in Chicago. COVID-19 had yet to circulate widely in the area. The case now serves as a cautionary tale, underscoring recommendations for people to keep their distance from anyone outside their immediate household, researchers report April 8 in Morbidity and Mortality Weekly Report. But how much distance is needed to avoid spreading the coronavirus? Six feet (or two meters) has become the mantra. The World Health Organization and other experts have said SARS-CoV-2, the virus that causes COVID-19, is spread mainly by large droplets sprayed when people cough or sneeze, contaminating surfaces. So that degree of separation, combined with frequent hand-washing, was thought to be enough to halt or at least slow the spread of the virus. But new evidence suggests six feet of distance may not be enough. If SARS-CoV-2 is airborne, as scientists think it may be, people could be infected simply by inhaling the virus in tiny aerosol droplets exhaled by someone talking or breathing. What’s actually safe is unknown. It may depend on many factors, including whether people are inside or outdoors, how loudly people are speaking, whether they are wearing masks, how well-ventilated a room is, and how far the virus can really fly.

4-17-20 An AI can tell whether ancient faeces came from a person or a dog
Dog faeces can still be troublesome thousands of years after being dumped. Archaeologists can end up in deep doodoo if they mistake it for human faeces. But now an artificial intelligence system has been developed to discern the two. Ancient faeces, or coprolites, can be a valuable source of information about the identity, diet and health of people who lived thousands of years ago. But dog faeces, which are a similar size and shape, are also common at many archaeological sites. “It is challenging to tell them apart,” says Maxime Borry of the Max Planck Institute for the Science of Human History in Germany. So his team has developed a method of identifying the source of ancient stools by sequencing the DNA preserved inside them. You might think that looking for human or dog DNA would be enough to reveal the identity of the dumper, but it isn’t that simple. Dog faeces often contain human DNA, thanks to their taste for tucking into the turds of other animals, including those of humans. On the flip side, ancient human faeces often contain dog DNA, because eating dogs was long commonplace in many communities all over the world. Because of this, Borry’s method looks at all the DNA in a coprolite, including that of the microbes living in the gut, which vary from species to species. His team trained a machine learning system dubbed coproID using existing data on human and canine microbiomes. The researchers checked the system by testing modern stool samples, and then applied it to 20 samples of soil or coprolites from archaeological sites where the source is known, or at least suspected. The soil samples didn’t fool the system and were classified as “uncertain”. Another seven samples were clearly identified as either dog or human. For instance, faeces found in a chamberpot in the UK didn’t appear human based on the parasites within. CoproID identified it as dog doodoo.

4-16-20 Why are men more likely to get worse symptoms and die from covid-19?
We know that older people are more vulnerable to covid-19, but another major risk factor has emerged: being male. The first signs of a sex difference in covid-19 severity emerged from hospital records in Wuhan shortly after the city locked down. On 30 January, a team at Shanghai Jiaotong University School of Medicine published a report on 99 covid-19 patients who were admitted to Jinyintan Wuhan hospital between 1 January and 20 January. They found that among those admitted, men outnumbered women by more than two to one. There has also been a sex difference among deaths. Mortality data from 21 hospitals in Wuhan between 21 and 30 January, for example, revealed that 75 per cent of those who died were men. Since then, larger studies from other countries have backed up these earlier findings. In England, Wales and Northern Ireland, for example, around 70 per cent of critically ill patients admitted to intensive care have been male, and a higher proportion of men than women have died. A study of more than 4000 covid-19 patients in New York City hospitals found that 62 per cent were male. The difference doesn’t appear to be caused by differential rates of infection: the New York study, for example, found that equal numbers of men and women catch the virus. But men are more likely to progress to severe illness and death. Two previous emerging coronavirus diseases, SARS and MERS, have also been found to disproportionately affect men. But this isn’t the case with respiratory infections generally. The report on England, Wales and Northern Ireland also looked at sex data on patients critically ill with viral pneumonia between 2017 and 2019, mostly due to influenza. There was an excess of men in this cohort too, but the ratio was less stark: 54 deaths for every 46 female deaths. (Webmaster's comment: Male ignorance and arrogance leads them to stupid behavior when it comes to dangerous activity.)

4-16-20 COVID-19 may be most contagious one to two days before symptoms appear
More than 4 in 10 coronavirus cases are spread by those not obviously sick, a study suggests. People with coronavirus infections may be most contagious one to two days before they start to feel ill, new research suggests. What’s more, considering pairs of people in which one person definitely caught the coronavirus from the other, scientists estimate that about 44 percent of COVID-19 cases may spread from person to person before symptoms appear. The results indicate that efforts to track down contacts of people with COVID-19 should include people encountered several days before a person’s symptoms start, researchers suggest April 15 in Nature Medicine. Scientists swabbed the noses of 94 coronavirus patients who were admitted to the Guangzhou Eighth People’s Hospital in China from January 21 through February 14. Amounts of the virus’s genetic material peaked quickly after the onset of symptoms, then declined over about 21 days, the team found. That result indicates that virus production may be strongest at the start of the infection before the immune system kicks in to kill viruses and produce symptoms. Analyzing 77 infector-infectee pairs allowed researchers to calculate when people are most contagious. The team estimates that contagiousness starts 2.3 days before symptoms begin and peaks 0.7 days before symptoms start. Those estimates are similar to findings based on a small number of people with COVID-19 in Germany, in which researchers isolated actual infectious virus, versus just genetic material, from the patients. That study found that infectious virus is produced before symptoms begin and in the first week of illness (SN: 3/13/20). One person in that study was asymptomatic, meaning he never even developed symptoms, but still produced infectious virus.

4-16-20 Earth's first life may have fuelled itself with a metal metabolism
The first living organisms may have relied on nickel and sulphur to obtain energy and sustain themselves. That is the conclusion of a study that shows how nickel sulphide can transform simple chemicals into many of the substances that underpin life. It is one of several recent studies indicating that life-like processes can be kick-started by metals. “We are able to build up important biomolecules from simple precursors,” says Claudia Huber at the Technical University of Munich in Germany. Huber and her colleagues have spent over 20 years investigating how life started. They focus on the origin of metabolism – the chemical reactions that organisms use to obtain energy and build their bodies. Modern organisms such as plants convert carbon dioxide into sugars – technically called “fixing” carbon – by carrying out intricate cycles of chemical reactions. These reactions are controlled by complicated molecules called enzymes, which cannot have existed when life started. So Huber’s team has studied whether other, simpler chemicals can make the reactions work. The team’s work was prompted by the ideas of Günter Wächtershäuser, a Munich patent lawyer who suggested in 1988 that iron sulphide kick-started the first metabolism. The researchers began with two carbon-based chemicals: carbon monoxide and acetylene. Both are thought to have been present when Earth was young. They mixed them with nickel sulphide, a common mineral, and heated them to 105°C – the sort of temperature seen in water heated by volcanic rocks. The result was a smorgasbord of carbon-based chemicals, including acetate, pyruvate and succinate. These chemicals are found in the metabolic processes used by all microorganisms, says Huber. It doesn’t stop there. “Our products undergo further reactions in the same system,” mimicking those that take place in living cells, says Huber. She thinks that the kind of carbon fixing reactions we see in plants and bacteria today could have evolved from these systems.

4-15-20 Why strength training may be the best thing you can do for your health
Building muscle reduces the risk of cancer and stroke, boosts brainpower, burns through calories and more – it might even be better for you than cardio. I AM lying on my living room floor, my whole body shaking, along with 30 strangers, who I can just about glimpse on little squares on my laptop screen. If you would have told me a month ago this would be my new workout routine, I would have laughed you out of the room. Until now, fitness for me meant getting out and about, religiously racking up steps on my pedometer. Then London went into lockdown, and for the past few weeks I have barely left the house. But here’s the thing – in terms of health benefits, my new exercise regime is through the roof. Unwittingly, these strange times have forced my habits in line with the latest thinking in exercise science. Aerobic exercise was once seen as the holy grail of fitness, but another kind of workout is just as important – if not more so. Something we can all do from the comfort of our homes without any equipment: strength training. Our muscle strength peaks in our 30s, then slowly declines. Eventually, it can drop so much that we are unable to get out of chairs or climb stairs. It isn’t just older people who would benefit from improving their strength, though. We are discovering unexpected health boosts from building muscle for all adults that go way beyond simply being strong. Strength training could add years of life and protect you from some major killers. Having stronger muscles seems to decrease the chance of getting cardiovascular disease, type 2 diabetes and cancer. There is even evidence that it can improve your memory and prevent cognitive decline. Its importance is so great that the UK government’s latest physical activity guidelines emphasise muscle strengthening over aerobic workouts. “It’s an urgent message that needs to get through,” says Stuart Gray, who studies metabolic diseases at the University of Glasgow, UK. “People need to know that strength training is important at any age.”

4-15-20 It's time to give the pedometer a break and embrace lifting weights
The incredible benefits of strength training are only just becoming apparent. That's good timing, when working out indoors is beneficial to everyone's health. “FOR the first time in history we can save the human race by lying in front of the TV and doing nothing. Let’s not screw this up.” The gag is just one of many similar memes doing the rounds on social media. If only things were so simple. For many, the idea of being cooped up at home for weeks or months on end without our usual means of exercise is daunting. Regular exercise brings many benefits, extending to both physical and mental well-being. But pounding the pavements could put us and others at risk. In many countries under lockdown, it is limited or even forbidden. There is a neat solution: strength training. As we report in our cover story, we are only now discovering just how beneficial this kind of exercise can be to our health. The science and government advice tends to be a step behind the fitness industry, which, over the past decade, has seen strength training burst out of the weights area of the gym into mainstream classes. The idea that pumping iron is solely for bodybuilders is now outdated. Even so, the benefits seem bigger than anyone could have imagined. As we reveal, building up your muscles can significantly reduce your risk of type 2 diabetes and cardiovascular disease, including stroke and heart attack. All told, a small amount of regular strength training can add years to your life. Everyone knows the benefits of getting your steps and getting out into nature. But do we all also realise how crucial strength is? The new findings should be a wake-up call. Only a quarter of us get enough strength exercise and yet it can be done in the comfort of your own home with very little space or equipment – all you need is something for your muscles to resist against, which could be a heavy book, or just your own body weight. In response to the pandemic, a vast menu of strength-training classes has been made available online, often for free.

4-15-20 Could the coronavirus trigger post-viral fatigue syndromes?
Conditions like chronic fatigue syndrome have been linked to viral infections, so it’s possible that the covid-19 virus may go on to trigger similar conditions. COULD the coronavirus sweeping around the world have a second illness following in its wake? We may expect to see an outbreak of post-viral fatigue syndromes in some people who have had covid-19, according to some researchers. Viral infections have previously been linked to problems with long-term fatigue symptoms. For example, chronic fatigue syndrome (CFS), which is also called myalgic encephalomyelitis (ME), sometimes occurs after viral infections. People who have CFS experience extreme fatigue and a range of other symptoms, such as pain and sensitivity to light, but the condition is poorly understood. So is it possible that the coronavirus could trigger similar fatigue syndromes? There are hints from the related SARS virus that this may happen. After the SARS outbreak of 2002 to 2003, some people in Toronto, Canada, who were infected were recorded as experiencing fatigue, muscle weakness and sleep problems up to three years later. During Toronto’s SARS outbreak, 273 people were diagnosed with the infection, of whom 44 died. After the outbreak had ended, Harvey Moldofsky, at the time a psychiatrist and sleep specialist at the University of Toronto, was asked to study 22 of those who had been infected and now had ongoing health problems that stopped them going back to work. Moldofsky’s team published its work in 2011. The researchers found that the participants generally had disturbed sleep, daytime fatigue, pain and weakness in muscles all over their body, and depression. “These symptoms were very reminiscent of CFS/ME,” says Moldofsky. His team only studied around 8 per cent of those diagnosed with SARS in Toronto, so we don’t know what proportion of people who had SARS experienced these symptoms afterwards. Nor is it known how long such symptoms lasted. While the current covid-19 pandemic is caused by a different virus, it is a member of the same coronavirus family, so it might also cause a post-viral fatigue syndrome, says Moldofsky. “That’s what I’m worried about.”

4-15-20 Wuhan’s covid-19 crisis: Intensive care doctors share their stories
Three doctors reveal what it was like at the heart of Hubei province’s coronavirus crisis, as the epidemic peaked in Wuhan and spread elsewhere. WUHAN – the city where the coronavirus pandemic began – has partially lifted its lockdown, with the epidemic that spread through the city and out across the surrounding province of Hubei under control for the time being. In early April, New Scientist spoke to three doctors about life at the peak of the province’s crisis. In terms of managing patients with covid-19, I personally think that preventing mild cases worsening to severe or even critical illness is important, by intervening early. The approach we take is the same as for other inflammatory responses. If a patient’s level of [the signalling molecule] interleukin-6 is high, we use monoclonal antibodies to suppress the generation of a cytokine storm [a severe and acute inflammatory response]. But this needs to be done early. If the patient’s situation is already very serious, then often it’s too late and nothing you do will work. One point – the most basic and, I think, the most difficult – is that you must provide ample space and facilities for people to quarantine. Having adequate facilities to screen patients is also important, including temperature testing and nucleic acid and antibody testing kits. Personal protective equipment is also important. My patients who are being treated are asked to wear masks when they can – even if they are on supplementary oxygen. Worry is warranted but it’s not necessary to panic. We should pay attention to social distancing and self-isolation. Protective materials such as masks should be worn if you are feeling unwell, even if you just have a cold.

4-15-20 Breastfed babies have fewer viruses in their guts that affect humans
A healthy set of gut bacteria seems to play a vital role in protecting us from a host of disorders – but what about the billions of viruses that interact with these bacteria? Although babies seem to be born without any such viruses, their guts become home to billions within the first month of life – and the community of viruses is shaped by whether the baby was breastfed or not. Plenty of studies over the past decade have shown that the collection of bacteria in our guts – known as the microbiome – is involved in a range of disorders. Disruption in gut bacteria have been linked to obesity, diabetes, depression and Parkinson’s disease, among others. But little is known about the viruses. Most of the viruses in our guts seem to infect the bacteria that line them. But we don’t really know what they are doing – the vast majority don’t show up in existing virus databases. That’s partly because there are so many viruses that have yet to be studied. “In a healthy adult, if we take some poop and purify the virus-like particle, we find something like a billion particles per gram,” says Frederic Bushman at the University of Pennsylvania. To find out more about the viruses, Bushman and his colleagues studied 20 babies. They collected faecal samples within a few days of birth, and again when the infants were 1 month old and 4 months old. The team searched for virus-like particles in each sample. These particles are thought to be viruses and look like viruses, but haven’t been through various tests to confirm that they really are. At birth, only three of the babies seemed to have any virus in their meconium – their earliest stool. This suggests that babies are born virus-free, and collect their first bugs either during birth or shortly after, says Bushman. But within a month, the babies had adult-levels of virus. As with adults, most of these viruses seem to be of the type that infect bacteria. But some are known to infect human cells. Viruses of this type were less common in babies that had been breastfed, the team found.

4-15-20 Life's other mystery: Why biology's building blocks are so lop-sided
Most molecules exist in mirror-image forms, and yet life prefers one over the other. How this bias began and why it persisted is one of the most baffling questions in biology – but now we have an answer. LIFE can be strange. Just look at narwhals, and those stick insects that resemble leaves on legs. Or consider the cockeyed squid, with its bizarrely mismatched peepers: one yellow and huge, the other tiny and blue. And yet almost nothing about life is as baffling as the lopsidedness at its core. All biological molecules have an inherent “handedness”: they can exist in two mirror-image forms, just like your left and right hands. But for each type of molecule it uses, life on Earth prefers a single form. So much so, in fact, that their opposite numbers are rarely seen in living things. How did life’s building blocks end up single-handed? The short answer is we don’t know. Some people have suggested that something happened in space to seed the predilection for left or right-handed molecules; others reckon it happened in shallow prebiotic pools where life is sometimes thought to have begun on Earth. Now, one researcher is claiming to have uncovered the first hints of a more convincing answer – one that could explain not only what broke life’s mirror in the first place, but also give a richer understanding of why the preference for one form of molecules has persisted over billions of years of evolution. The answer comes not from deep space or deep time, but from the quantum nature of matter. And if the latest discoveries are anything to go by, its unexpected influence on the building blocks of life could solve the mirror mystery once and for all by revealing in fine detail why some of the most fundamental processes in biology work so beautifully.

4-15-20 The new mysteries of coronavirus
What should be done as we try to unravel them? n some of the hardest hit parts of the West, the pandemic is starting to peak. In Italy, the daily number of new confirmed cases peaked on March 21; the daily number of deaths peaked on March 27. In New York, the peak day for new confirmed cases may have been April 4, and new deaths are trending down. It is entirely reasonable for these countries and states to start talking about — and planning for — a relaxation of restrictions and a resumption of economic and social life on some terms. But what terms? To be effective, any strategy for relaxing restrictions needs to be informed by a more detailed understanding of the virus — what facilitates its spread, and where its spread is most dangerous. Unfortunately, as the pandemic has progressed, everything we've learned has simultaneously opened up new mysteries, ones with a direct bearing on addressing the next phase of the crisis. Why does Europe's case fatality rate appear to be so much worse than America's? Belgium has a case fatality rate of nearly 13 percent. America's is about 4 percent. And it's not just an artifact of testing; Belgium and America have each tested at almost the identical rate, about 8,800 people per million. Moreover, New Jersey — one of the densest states with the second-highest case rate and the second-highest death rate in America — has a case fatality rate comparable to the national average. Even New York, the worst-hit state, has a case fatality rate of 5 percent. Why? Case fatality rates like those are all eye-wateringly terrifying, but they are well-known to be overestimates of the true fatality rate because most people who have had the virus and don't develop severe symptoms are still not being tested. But how prevalent have COVID-19 infections been already? No one seriously believes that we've gotten anywhere close to herd immunity in the general population — but estimates of the number of asymptomatic or mildly symptomatic cases vary enormously. A recent German study estimated that, globally, infection rates could be 30 to 80 times higher than the official tallies. A Massachusetts study of viral particles in sewage had an even wider range; it estimated that the true number of infections could be from 5 to 250 times higher than the number of confirmed cases. Even if we're nowhere near herd immunity, the differences between the low and high end range have vast implications for public health — because they paint very different pictures of both how infectious and how deadly the virus is. At the low end, we'd know that we'd acted in time to significantly slow the spread of the disease, and that a "pump the breaks" strategy would therefore be a feasible response to future outbreaks — and a necessary one, because widespread outbreaks could lead to mass fatalities. (And fatality counts are also fuzzier than one would like, since people dying at home who haven't been tested won't get counted in the COVID-19 totals.) At the high end, meanwhile, we reach the opposite conclusion: We acted far too late to restrain the spread of COVID-19, but the virus is far less-deadly than anticipated. If that is the case, the focus going forward should be overwhelmingly on protecting vulnerable populations.

4-14-20 Psychology tips for maintaining social relationships during lockdown
Robin Dunbar has spent decades studying relationships, social bonding and the importance of touch and grooming in forging and sustaining our ties to others. As much of the world remains in lockdown, unable to meet loved ones and friends in person, New Scientist caught up with him to ask what implications this might have. For all mammals, including us, grooming triggers the endorphin system [which relieves stress and pain]. Brain-imaging studies looking at people being stroked show that their endorphin receptors go absolutely crazy. With our closer friends and family, you actually do a lot of casual stroking and touching and hugging that we don’t think about, it’s all going on below the event horizon of consciousness. Not only does this make you feel happy, because it releases endorphins, which raise your pain thresholds and make you feel relaxed and much more trusting, but it also seems to kick on the immune system, making you more resistant to diseases. For most people, in the short term, I would say no. Everything hinges on how long this lasts. Clearly, the expectation is that it’s only going to be a few months and then we’re going to be back to normal. You can also trigger this same endorphin system by going for a jog, for instance. To increase the size of our social groups, we’ve discovered ways of triggering the endorphin system that don’t involve touch. All of the singing from balconies and in streets. Singing is one of the social mechanisms we use. There’s laughter, singing, dancing, eating socially, drinking socially, all of those kinds of things are what we use to enlarge our social circle. Physical grooming is very intimate. This is what ultimately limits the size of primates’ social groups. They don’t have enough time in the day to groom more than a set number of individuals, and the quality of the relationship depends on the time invested in it. So going out to clap for healthcare workers and the like probably makes you feel better.

4-14-20 UK Biobank: DNA to unlock coronavirus secrets
A vast store of DNA is being used to study why the severity of symptoms for coronavirus varies so much. UK Biobank - which contains samples from 500,000 volunteers, as well as detailed information about their health - is now adding Covid-19 data. It is hoped genetic differences could explain why some people with no underlying health conditions can develop severe illness. More than 15,000 scientists from around the world have access to UK Biobank. Prof Rory Collins, principal investigator of the project, said it would be “a goldmine for researchers”. “We could go very quickly into getting some very, very important discoveries,” he said. Some people with coronavirus have no symptoms - and scientists are trying to establish what proportion this is. Others have a mild to moderate disease. But about one in five people has a much more severe illness and an estimated 0.5-1% die. UK Biobank has blood, urine and saliva samples from 500,000 volunteers whose health has been tracked over the past decade. And it has already helped to answer questions about how diseases such as cancer, stroke and dementia develop. Now, information about positive coronavirus tests, as well as hospital and GP data, will be added. Prof Collins said: “We’re looking at the data in UK Biobank to understand the differences between those individuals. “What are the differences in their genetics? Are there differences in the genes related to their immune response? Are there differences in their underlying health? “So it is a uniquely rich set of data - and I think we will transform our understanding of the disease.” Researchers will be scouring the entire genome, searching for tiny variations in DNA. One area of particular interest is the ACE2 gene, which helps make a receptor that allows the virus to enter and infect cells in airways. In addition to the UK Biobank study, a team led by Prof Jean-Laurent Casanova, from the Rockefeller University, in New York, is planning to study people under 50 with no underlying medical conditions who are taken into intensive care units.

4-14-20 Ancient nomadic warrior women may have inspired the Mulan legend
Ancient remains found in the Mongolian steppe suggest that the story of the female warrior Mulan may have been inspired by real Xianbei women who rode horseback and probably also used bows and arrows. According to folklore, a powerful East Asian ruler demanded every family send one man to swell the ranks of his army, and a girl named Mulan faced a difficult choice: either let her weak father go to war, or take his place. Now it seems there may be truth to this age-old Ballad of Mulan. Christine Lee and Yahaira Gonzalez at California State University examined skeletons from 29 ancient burials across Mongolia. The burials belonged to three groups of nomadic people: the Xiongnu, who began to occupy the region about 2200 years ago, the Xianbei, who took over around 1850 years ago, and the Turkic people, who displaced the Xianbei roughly 1470 years ago. Three of the skeletons belonged to Xianbei women – and two were potentially warriors. Lee and Gonzalez reached this conclusion partly due to the nature of marks left on the bones where muscles once attached. The marks are larger if the muscle was heavily used, and the pattern of marks on both women’s skeletons suggests they had routinely worked the muscles someone on horseback would use. There were also indications that they practised archery. Lee was surprised by the discovery. “The number of women allowed to participate in these activities must have been really small,” she says, adding that Mongolian history suggests that it was rare for women to do either. Markings on three other skeletons indicate that Xiongnu women may also have engaged in archery and horseback riding to a limited degree. Another three skeletons indicate that Turkic women apparently didn’t practise archery, although they seem to have spent a limited amount of time riding horses. There may be a simple reason why some Xianbei women may have become warriors: the political landscape was particularly unstable when they were alive. After the Han dynasty in China ended in AD 220, there was intermittent violence across the region for centuries.

4-14-20 Coronavirus: How to cope with living alone in self-isolation
After years of living with others, Lucia was excited to finally have a place to herself. The photographer had recently moved back to Italy from New York. She enjoyed spending time on long, meandering walks with her camera, and going out for food with friends. But within a couple of months Milan, where she lived, had become the epicentre of Europe's coronavirus outbreak. She and millions of other Italians were ordered into lockdown, told to stay home unless absolutely necessary. The first few weeks were the hardest, as the monotony of days isolated in her apartment took its toll. But now more than a month on, Lucia is adjusting to being alone. She still misses her freedom and physical contact with others, but feels fortunate that she and her loved ones are healthy, when so many across her country have died. "Sometimes I get worried about the future, about how life will be after this ends," she says. "I wonder if there will ever be a real life outside our homes." Almost 4,000 miles away, the only human faces Aparna sees now belong to security guards. The 26-year-old lives alone in her mother's old apartment in Gurgaon, near Delhi. Twice a day she leaves to walk her dogs, Jules and Yogi, as the guards keep watch over her complex's locked gates. Aparna has only ventured beyond them once. There are millions more stories like this around the world. As governments scramble to contain the deadly Covid-19 pandemic by restricting public life, many living alone have had to accept that they might not spend time with anyone else for a long time. I know because I'm among them. Weeks into the UK lockdown, my ordinary life in London goes on but it looks and feels different. Trips to the office have become a rarity. I feel lucky to have a cat for company and the ability to go outside for walks when others can't, but it's hard not knowing when I'll next see my close friends or family, who live hundreds of miles away.

4-14-20 Measles resurgence fear amid coronavirus
Measles outbreaks may occur as a result of the coronavirus pandemic, officials say, because some vaccination programmes are having to be delayed. Unicef says 117 million children in 37 countries may not get immunised on time. There have been several large outbreaks in countries across Europe where MMR vaccine uptake has been low. The UK has already lost its measles-free status, because of rising cases of the potentially deadly infection. The disease, which causes coughing, rashes and fever, can be prevented by two doses of the mumps, measles and rubella (MMR) vaccine, available free to all young children in the UK. Here, 95% of five-year-olds have had the first jab - the World Health Organization (WHO) target - but only 87.4% have had the second. And as measles is highly infectious, even small declines in uptake can have an impact. The WHO says countries with no active outbreak of measles can temporarily pause their immunisation campaigns if necessary. And 24 countries, including several already dealing with large measles outbreaks, have decided to delay because of the coronavirus pandemic: • Bangladesh • Brazil • Bolivia • Cambodia • Chad • Chile • Colombia • Djibouti • the Dominican Republic • the Democratic Republic of Congo • Ethiopia • Honduras • Kazakhstan • Kyrgyzstan • Lebanon • Maldives • Mexico • Nepal • Nigeria • Paraguay • Somalia • South Sudan • Ukraine • Uzbekistan. But Unicef says even more may face disruptions. "If the difficult choice to pause vaccination is made due to the spread of coronavirus, we urge leaders to intensify efforts to track unvaccinated children so that the most vulnerable populations can be provided with measles vaccines as soon as it becomes possible to do so," it said. Spokeswoman Joanna Rea added: "Disruptions to routine vaccine services will increase the risk of children contracting deadly diseases, compound the current pressures on the national health services and risks a second pandemic of infectious diseases." The UK continues to offer children MMR as part of its routine immunisation schedule.

4-14-20 Three new Ebola cases detected in Democratic Republic of the Congo
Fresh cases of Ebola have been detected just days before the deadly epidemic in eastern Democratic Republic of the Congo was to be declared over. The Ministry of Health on Friday confirmed the death from Ebola of a 26-year-old man in the city of Beni, North Kivu province. An 11-month-old girl treated at the same health centre also died, it was announced on Sunday, and a seven-year-old girl is also currently being treated for the virus. It marks a significant blow for the Central African country, which had recorded its last Ebola case on 17th February and was on the verge of ending an outbreak that has killed more than 2200 people since August 2018. The World Health Organization (WHO) said that even before the announcement it was prepared for further cases to emerge. “While not welcome news, this is an event we anticipated,” said Tedros Adhanom Ghebreyesus, the WHO’s director general, in a media statement. “We kept response teams in Beni and other high-risk areas for precisely this reason.” As part of the Ebola surveillance system, health teams on the ground are investigating alerts every day. These can either be reports of those with Ebola symptoms or of deaths in areas that are considered high risk. The WHO said 2600 alerts are currently being analysed across the country’s eastern provinces. Health authorities had already planned to remain on high alert for the next 80 days, and to provide care for Ebola survivors as part of an 18-month programme of regular check-ups. Efforts are now underway to find all potential contacts of the cases in order to offer them vaccination and to monitor their health. If no new cases emerge, the DRC will now have to wait another 42 days – the equivalent of two incubation periods for the virus – until the Ebola epidemic can be declared over. The setback underlines the huge challenge posed in eradicating a virus. The problem is made worse by the emergence of coronavirus in the DRC last month.

4-13-20 50,000-year-old string found at France Neanderthal site
A piece of 50,000-year-old string - the oldest yet discovered - found in a cave in France has cast further doubt on the idea that Neanderthals were cognitively inferior to modern humans. A study published in Scientific Reports said a tiny, three-ply cord fragment made from bark was spotted on a stone tool recovered from the Abri du Maras. It implies that Neanderthals understood concepts like pairs, sets and numbers. Twisted fibres provide the basis for clothes, bags, nets and even boats. Neanderthals - whose species died out about 40,000 years ago - are already known to have made birch bark tar, art and shell beads. They also controlled fire, lived in shelters, were skilled hunters of large animals and deliberately buried their dead in graves. Typically, archaeologists and paleoanthropologists only find faunal remains or stone tools at sites like the Abri du Maras. Perishable materials are usually missing. But a team of researchers from France, the US and Spain discovered a fragment of cord adhering to the underside of a 60mm- (2.4-inch-) long stone tool. The cord, believed to have been made with the inner bark of a conifer tree, was approximately 6.2mm long and 0.5mm wide. Three groups of fibres were separated and twisted clockwise in an "S-twist". Once twisted, the strands were twined anti-clockwise in "Z-twist" to form a cord. The study - whose lead author was Bruce Hardy of Kenyon College in Ohio - concluded that the production of the cord demonstrated that Neanderthals had a detailed ecological understanding of trees and how to transform them into entirely different functional substances. The production of the cord also implied a cognitive understanding of numeracy and context-sensitive operational memory, according to the study. That is because it required keeping track of multiple, sequential operations simultaneously. "Given the ongoing revelations of Neanderthal art and technology, it is difficult to see how we can regard Neanderthals as anything other than the cognitive equals of modern humans," the study said.

4-12-20 Sometimes the most powerful act of resistance is to do nothing
If we are unable to join protestors, we still have duties to support them with our conscious inactions. Resistance is a human right. This is why the preamble of the Universal Declaration of Human Rights states that people will be "compelled to have recourse, in the last resort, to rebellion" if human rights are not respected, and why the defense of human rights framed in many United Nations resolutions supports resistance against colonialism and apartheid. It could not be otherwise. If your rights are violated, you must have a recourse. Normally this would be found in the law and the courts but, when faced with severe and intransigent injustice, resistance is that recourse. But when others are resisting, and we are sympathetic to their aims, what should we do? The answer is surprising. From autumn 2018 for about a year, the group known as Extinction Rebellion (XR) staged a number of disruptive protests in the United Kingdom, on London's bridges and across several city centers, bringing road traffic to a standstill. The protestors were drawing attention to the need for immediate action on the climate emergency. From their perspective, these were acts of resistance, drawing attention to injustice and inaction. What should someone who is sympathetic to this cause and to their action do? If possible, nothing. But there are different ways of doing nothing. It matters that you do nothing in the right way and for the right reasons. Let me explain. Rights imply duties. If you have a right to something, other people owe you certain duties. There are at least three negative duties that are generated by the right of resistance: non-interference, non-obstruction, and non-collaboration. The simplest of these is the duty of non-interference. If a person has the right to do something, there is a fundamental duty not to prevent them from doing that thing. So, if a person is enacting their right to resistance, then bystanders have an obligation to forbear and not to interfere. This seems obvious, but there was a rather shocking instance during the London XR protests where this duty was not respected. In October 2019, protestors stopped London trains from working by climbing on top of carriages. At Canning Town in east London, one protestor was dragged off the roof of a carriage and set upon by commuters. This is a violation of the duty of non-interference. It might be that people were angered by having their day disrupted, but this doesn't excuse their behavior. It might be irritating but we have an obligation to do nothing.

4-11-20 Why African-Americans may be especially vulnerable to COVID-19
African-Americans are more likely to die from than the disease than white Americans. COVID-19 was called the great equalizer. Nobody was immune; anybody could succumb. But the virus’ spread across the United States is exposing racial fault lines, with early data showing that African-Americans are more likely to die from the disease than white Americans. The data are still piecemeal, with only some states and counties breaking down COVID-19 cases and outcomes by race. But even without nationwide data, the numbers are stark. Where race data are known — for only 3,300 of 13,000 COVID-19 deaths — African-Americans account for 42 percent of the deaths, the Associated Press reported April 9. Those data also suggest the disparity could be highest in the South. For instance, in both Louisiana and Mississippi, African-Americans account for over 65 percent of known COVID-19 deaths. Other regions are seeing disparities as well. For instance, in Illinois, where the bulk of infections are in the Chicago area, 28 percent of the 16,422 confirmed cases as of April 9 were African-Americans, but African-Americans accounted for nearly 43 percent of the state’s 528 deaths. Other data find similar trends. A study published online April 8 in the U.S. Centers for Disease Control and Prevention’s Morbidity and Mortality Weekly Report looked at hospitalizations for COVID-19 across 14 states from March 1 to 30. Race data, which were available for 580 of 1,482 patients, revealed that African-Americans accounted for 33 percent of the hospitalizations, but only 18 percent of the total population surveyed.

  1. African-Americans are more likely to be exposed to COVID-19. SARS-CoV-2, the coronavirus that causes COVID-19, is highly contagious, even before symptoms appear (SN: 3/13/20). So to curb the virus’ spread and limit person-to-person transmission, states have been issuing stay-at-home orders. But many individuals are considered part of the critical workforce by the U.S. Department of Homeland Security and must continue to work. That includes caregivers, cashiers, sanitation workers, farm workers and public transit employees, jobs often filled by African-Americans.
  2. African-Americans have a higher incidence of underlying health conditions. Among those at highest risk of getting severely ill with COVID-19 are patients with other serious health problems, such as hypertension, diabetes and heart disease (SN: 3/20/20). Over 40 percent of African-Americans have high blood pressure, among the highest rates in the world, according to the American Heart Association. By comparison, about a third of white Americans have high blood pressure. Similarly, African-Americans tend to have higher rates of diabetes.
  3. African-Americans have less access to medical care and often distrust caregivers. Inequities in access to health care, including inadequate health insurance, discrimination fears and distance from clinics and hospitals, make it harder for many African-Americans to access the sort of preventive care that keeps chronic diseases in check.

4-10-20 How materials science has changed humankind — for better and worse
The Alchemy of Us explores how new technologies have altered humans and society. Humans have continually wielded materials, from steel to silicon, in new ways to send technology leaping forward. But those technologies have unintentionally molded our bodies and society, materials scientist and science writer Ainissa Ramirez argues in The Alchemy of Us. Increasingly precise clocks — based on steel springs and then quartz crystals — kept society humming along in unison. But with the Industrial Revolution’s focus on factory schedules, humans became ever more obsessed with time, and our sleep habits suffered. Likewise, electric lights made with carbon filaments let people work and play for longer hours, but upset circadian rhythms, with a variety of negative health impacts (SN: 10/17/16). But the knock-on effects haven’t been all bad: Telegraph wires of iron and copper allowed news to travel quickly across the United States beginning in the 1840s. The technology’s demand for short communications helped shape the clipped style of American newspapers, whose reporters used the technology to send dispatches from afar. That style inspired the concise, clear prose of Ernest Hemingway, Ramirez argues. Packed with engaging, little-known stories from the history of science, the book provides sharp, straightforward explanations of the materials science behind these tales. Ramirez carefully selects the characters in her narratives, making for a refreshing departure from the lone scientific genius trope. Instead, we meet Ruth Belville, who carried around a highly accurate pocket watch and “sold time” in early 20th century England, and chemist Caroline Hunter and photographer Ken Williams, Polaroid employees who in the 1970s fought their employer over the use of instant photography to monitor South Africans during apartheid.

4-10-20 Warm weather probably won’t slow COVID-19 transmission much
Any seasonal benefit can be canceled by humanity’s vulnerability to the virus, a study suggests. The arrival of spring in the Northern Hemisphere has raised hopes that warmer and wetter weather might slow or even stop the COVID-19 pandemic, at least until fall. But don’t plan on that happening, U.S. health experts say. “One should not assume that we are going to be rescued by a change in the weather. You must assume that the virus will continue to do its thing,” Anthony Fauci, director of the U.S. National Institute of Allergy and Infectious Diseases in Bethesda, Md., and a member of the White House coronavirus task force, said during an interview April 9 on ABC’s Good Morning America. A report released April 7 by the National Academies of Sciences, Engineering and Medicine also says that, while much about the virus remains unknown, summer temperatures probably won’t do much to dampen the spread of the virus. While scientists still don’t know if touching shared surfaces is a major driver of the pandemic, compared with direct person-to-person transmission (SN: 3/4/20; SN: 4/2/20), understanding how the virus fares in different environmental conditions could provide clues as to the likelihood of a summertime slowdown. Many viruses wither under high temperatures and there is some evidence that the same might be true for SARS-CoV-2, the novel coronavirus that causes COVID-19. In an experiment using SARS-CoV-2 in a lab solution, increasing temperature decreased the amount of viable virus that could be detected, according to an April 2 study in the Lancet Microbe. No infectious virus remained after 30 minutes at 56° Celsius (133° Fahrenheit). And just five minutes at 70° C was enough to inactivate the pathogen. But these temperature highs are rare, if not impossible, in the lower atmosphere. The National Academies’ report — aimed at updating the White House on how changing seasons might affect the pandemic — instead points to other, ongoing studies at national laboratories that could soon inform how the virus fares under a wider range of conditions.

4-10-20 Meet Sophia Upshaw, a volunteer in a coronavirus vaccine trial
Nearly 50 people in Seattle and Atlanta have begun receiving injections of a potential vaccine. Scientists are racing to develop and test vaccines that can protect people from the coronavirus. One particularly swift effort, sponsored by the National Institute of Allergy and Infectious Diseases, involves a vaccine called mRNA-1273, made by pharmaceutical company Moderna, Inc., in Cambridge, Mass. Traditional vaccines use a weakened or inactive version of viruses or their parts to spark an immune response. In contrast, mRNA-1273 contains genetic material called messenger RNA, which carries instructions for making one of the coronavirus’s proteins. The idea is that human cells will take those instructions and make this viral protein. Then, the body will learn how to produce antibodies that target the protein, jump-starting an immune reaction against the real thing, should it ever be encountered (SN: 2/21/20). Two research sites — Kaiser Permanente Washington Health Research Institute in Seattle and Emory University’s Vaccine and Treatment Evaluation Unit in Atlanta — have begun testing the safety of the vaccine in 45 participants. Science News spoke to Sophia Upshaw, a 22-year-old graduate student in Atlanta who recently received the first of two doses of the experimental vaccine. She’ll have regular clinic visits for the duration of the study, which will last about 14 months. Her responses have been edited for clarity. It’s a different perspective to see the doctors and nurses involved in the vaccine trial and how hard they’re working. It’s amazing to see their dedication to this. This has dominated their work right now. I’m really appreciative of their work, and how well they’ve treated me and everyone in the vaccine trial to make us feel comfortable.… I’m very grateful to be a part of [the trial]. We’ll see how things turn out in a year or so. That seems like a long way away.

4-10-20 Two primate lineages crossed the Atlantic millions of years ago
New fossil discoveries suggest a second group crossed about 35 million to 32 million years ago. Four fossilized molar teeth excavated in Peru’s Amazon basin come from a now-extinct lineage of primates that rafted across the Atlantic Ocean from Africa and reached the inland site between around 35 million and 32 million years ago, researchers say. Until now, South American sites had yielded only fossils of primates ancestral to those inhabiting the continent today. Fossils from the same Peruvian site had previously suggested that ancestors of modern South American monkeys crossed the ocean from Africa by around 36 million years ago (SN: 2/4/15). The new discovery adds a second group of primate arrivals. The teeth closely resemble those of parapithecids, a primate family that inhabited northern Africa from roughly 56 million to 23 million years ago, say paleontologist Erik Seiffert of the University of Southern California in Los Angeles and his colleagues. Like ancestors of living South American monkeys, parapithecids must have made a sea crossing on vegetation mats created by storms, the scientists conclude in the April 10 Science. Favorable ocean currents and a narrower Atlantic Ocean than today because of lower sea levels helped ancient primates float across the ocean. Still, the Atlantic probably was more than 1,500 to 2,000 kilometers wide when crossings occurred, the scientists say. The two primate lines adjusted well to a new continent, traveling from where they landed in South America more than 4,000 kilometers to the inland Peruvian site, the researchers say. Seiffert’s group suspects both groups competed for resources until Ucayalipithecus, the genus name given to the newly reported fossils, eventually died out.

4-9-20 Monkeys made their way from Africa to South America at least twice
Two lineages of ancient monkey migrated from Africa to South America more than 30 million years ago. But we aren’t sure which ones got there first. Monkeys originated in Africa and the first group known to have reached South America are thought to have migrated there up to 40 million years ago, when the land masses were probably between 1500 and 2000 kilometres apart, around a quarter of the distance now. But recent fossil discoveries, including that of fossilised teeth from a second lineage of African monkey, tell a slightly different story. Erik Seiffert at the University of Southern California and his colleagues analysed the fossilised teeth, which were originally discovered in Santa Rosa, Peru. “This discovery was just so incredibly fascinating, I was very excited,” says Seiffert. He and his colleagues analysed four fossilised teeth and discovered that their shape doesn’t match that of the only previously known group of ancient monkeys from South America, called platyrrhines. Instead, the teeth look much more like those of an extinct group of African monkeys called the parapithecids. “Mammalian teeth are extremely diverse in shape, and so, for palaeontologists, are almost like fingerprints that sometimes allow us to identify species from only a single tooth or even a partial tooth,” says Seiffert. If they do belong to this group, it will be the first time parapithecid fossils have been discovered in South America, says Seiffert. It suggests that the ancestors of platyrrhine monkeys aren’t the only ones who made the trans-Atlantic voyage, he says. Both lineages are thought to have crossed the ocean on a large raft of floating vegetation. Fossil dating indicates that the second lineage of monkey made it across the Atlantic Ocean between 35 and 32 million years ago. This time frame coincided with a major drop in sea level that could have helped the animals to migrate by shortening their journey.

4-9-20 Mysteries of decorated ostrich eggs in British Museum revealed
If you wanted to give an extravagant gift 5,000 years ago, you might have chosen an ostrich egg. Now some of these beautiful Easter egg-sized objects are in London's British Museum. The eggs were found in Italy but their origins have long been a mystery - ostriches are not indigenous to Europe. Now, research into the museum's collection by an international team of archaeologists reveals new insights into their history. People across Europe, the Mediterranean and North Africa traded ostrich eggs up to 5,000 years ago, in the Bronze and Iron Ages. Eggs were decorated in many ways - painted, adorned with ivory or precious metals, or covered in small glazed stones or other materials. The five eggs in the British Museum's collection are embellished with animals, flowers, geometric patterns, soldiers and chariots. Archaeologists usually find the eggs in the burial sites of wealthier individuals and they were probably luxury items, explains Dr Tamar Hodos, the project leader at the University of Bristol. But working out where the eggs were laid can reveal more about their history, the new research published on Thursday in the journal Antiquity says. Dr Hodos's team were keen to find out where the ostrich eggs came from, and whether the ostriches were wild or farmed. Wild ostriches are extremely dangerous, so much so that ancient Greek historian Xenophon wrote that no-one managed to capture them. Finding out this type of information helps us better understand the ancient civilisations and trade patterns that laid the foundation for the modern world. The archaeologists analysed isotopes, or chemical elements, in the egg shells. Using modern ostrich eggs from Egypt, Israel, Jordan and Turkey, the researchers compared isotopes in ancient and modern eggs to trace their origins.

4-9-20 Oldest ever piece of string was made by Neanderthals 50,000 years ago
A piece of 50,000-year-old string found in a cave in France is the oldest ever discovered. It suggests that Neanderthals knew how to twist fibres together to make cords – and, if so, they might have been able to craft ropes, clothes, bags and nets. “None can be done without that initial step,” says Bruce Hardy at Kenyon College in Gambier, Ohio. “Twisted fibres are a foundational technology.” His team has been excavating the Abri du Maras caves in south-east France where Neanderthals lived for long periods. Three metres below today’s surface, in a layer that is between 52,000 and 41,000 years old, it found a stone flake, a sharp piece of rock used as an early stone tool. Examining the flake under a microscope revealed that a tiny piece of string (pictured top right), just 6 millimetres long and 0.5 millimetres wide, was stuck to its underside. It was made by twisting a bundle of fibres in an anticlockwise direction, known as an S-twist. Three bundles were twisted together in a clockwise direction – a Z-twist – to make a 3-ply cord. “It is exactly what you would see if you picked up a piece of string today,” says Hardy. The string wasn’t necessarily used to attach the stone tool to a handle. It could have been part of a bag or net, the team speculates. The string appears to be made of bast fibres from the bark of conifer trees, which helps establish that it isn’t a stray bit of modern string, because “nobody at the site was wearing their conifer pants at the time”, says Hardy. “It’s so fine. That’s really surprising,” says Rebecca Wragg Sykes at the University of Bordeaux in France. This suggests the string wasn’t used for heavy-duty tasks, but instead as some kind of thread, she says. Before this find, the oldest known string came from 19,000 years ago. This was discovered in the Ohalo II site near the Sea of Galilee, Israel, and is associated with modern humans. But Hardy says the newly found string was made by Neanderthals, as there were no modern humans in this part of Europe at this time.

4-8-20 Fever can help the immune system, so what should we do if we have one?
Fever is a pain, quite literally, but new evidence shows why it can also be good for us. Here’s what you need to know. AS NEWS about coronavirus spread around the world, paracetamol soon began to disappear from shop shelves as people stocked up at home. In some places, the price of the drug shot up. That probably comes as little surprise given that one of the key symptoms of the infection is a fever. We tend to routinely use drugs such as paracetamol or ibuprofen to try to bring down a high temperature, believing fever to be, at best, a passive and unwelcome bystander to infection and, at worst, a direct contributor to our illness. Yet mounting evidence suggests that fever may, in fact, be a strategy the body uses to ramp up its defences. This new understanding of what is going on when we are burning up could help us come up with better approaches to fighting infection altogether. Normal body temperature is generally thought of as 37°C, although anything between 36.5°C and 37.5°C is considered normal (see “Highs and lows”, overleaf). However, once your temperature hits 38°C, you have officially got a fever. The most common cause of this is infection. “When immune cells recognise the telltale signs of a germ in the body – and often this can be quite early on in an infection – they release secretions which act on a brain area called the hypothalamus,” says Daniel Davis, an immunologist at the University of Manchester, UK, and author of The Beautiful Cure: Harnessing your body’s natural defences. The hypothalamus is responsible, among other things, for controlling body temperature, and it responds to these signals by releasing hormones that cause various heat-boosting responses. Blood vessels in our skin constrict so less heat is lost at the body’s surface. Fat cells start burning energy and our muscles rapidly contract, causing shivering – both of which warm us up. As a result, the body’s temperature starts to rise. If it rises too far, that can be fatal. Our cells begin to die, releasing proteins into the blood that can damage the kidneys and other organs, resulting in their failure. The exact temperature this happens at probably depends on the source of a person’s fever, as well as other factors such as how hydrated they are. “The number 40 [degrees] scares a lot of doctors,” says Mark Peters at the UCL Great Ormond Street Institute of Child Health in London.

4-8-20 Urine test can predict how much a baby will grow in six months’ time
We can now use urine or blood samples to predict how well an infant is likely to grow over its next six months. Margaret Kosek at the University of Virginia and her colleagues have developed a predictive model that can forecast infant growth based on the presence of several biomarkers. They believe this could be used to improve interventions for children in developing countries who are chronically malnourished. Over two years, the researchers took urine at regular intervals from 779 infants in Bangladesh, Peru and Tanzania who were aged 3 months to 2 years. They also measured the children’s body length every month from birth. A subset of these children, who were in roughly the top 9 per cent for linear growth, were used as a healthy reference group. These were infants who were growing well despite adversity, says Kosek, although their height and growth was often below the median for well-nourished children in other countries. The team measured eight different compounds excreted in urine and found significant differences in levels of certain metabolites between the healthy growers and the other children. Children with constrained growth lagged in metabolic maturity relative to their healthier peers, and this was evident as early as 3 months old. The metabolites that were most predictive for growth were those associated with the citric acid cycle, also known as the Krebs cycle – a series of chemical reactions our cells use to generate energy. Another was betaine, which is associated with the metabolism of tryptophan, an essential amino acid. The research suggests that children in the countries involved in the study could be more protein-deprived that previously thought. “We’ve measured their protein intake and most of them are getting what we think are adequate protein intakes,” says Kosek. But the metabolic signatures they found suggest that children in these regions, who are exposed to infectious diseases more frequently, may have increased nutritional requirements.

4-8-20 Crops were cultivated in regions of the Amazon '10,000 years ago'
Far from being a pristine wilderness, some regions of the Amazon have been profoundly altered by humans dating back 10,000 years, say researchers. An international team found that during this period, crops were being cultivated in a remote location in what is now northern Bolivia. The scientists believe that the humans who lived here were planting squash, cassava and maize. The inhabitants also created thousands of artificial islands in the forest. Perhaps the most important of these was that early civilisations began to move away from living as hunter-gatherers and started to cultivate crops for food. Researchers have previously unearthed evidence that crops were domesticated at four important locations around the world. So China saw the cultivation of rice, while in the Middle East it was grains, in Central America and Mexico it was maize, while potatoes and quinoa emerged in the Andes. Now scientists say that the Llanos de Moxos region of southwestern Amazonia should be seen as a fifth key region. The area is a savannah but is dotted with raised areas of land now covered with trees. The area floods for part of the year but these "forest islands" remain above the waters. Some 4,700 of these small mounds were developed by humans over time, in a very mundane way. "These are just places where people dropped their rubbish, and over time they grow," said lead author Dr Umberto Lombardo from the University of Bern, Switzerland. "Of course, rubbish is very rich in nutrients, and as these areas grow they rise above the level of the flood during the rainy season, so they become good places to settle with fertile soil, so people come back to the same places all the time." The researchers examined some 30 of these islands for evidence of crop planting. They discovered tiny fragments of silica called phytoliths, described as tiny pieces of glass that form inside the cells of plants. The shape of these tiny glass fragments are different, depending on which plants they come from. The researchers were able to identify evidence of manioc (cassava, yuca) that were grown 10,350 years ago. Squash appears 10,250 years ago, and maize more recently - just 6,850 years ago.

4-8-20 Coronavirus: Exploiting nature 'drives outbreaks of new diseases'
New evidence has emerged of a link between human exploitation of nature and pandemics. Close contact with wild animals through hunting, trade or habitat loss puts the world at increased risk of outbreaks of new diseases, say scientists. Coronavirus is thought to have originated in bats, with other wild animals, possibly pangolins, playing a role in transmission to humans. There are strong indications of a wildlife source and a link to trade. In the latest study, researchers trawled scientific papers for reports of diseases that have crossed from animals to humans, then combined this data with information on extinction risk compiled by the International Union for the Conservation of Nature (IUCN). Wild animals at risk of extinction due to human exploitation were found to carry over twice as many viruses that can cause human disease as threatened species listed for other reasons. The same was true for threatened species at risk due to loss of habitat. "As natural habitat is diminished, wildlife come into closer contact with people," Dr Christine Johnson of the University of California, Davis, US, told BBC News, "Wildlife also shift their distributions to accommodate anthropogenic activities and modification of the natural landscape. This has hastened disease emergence from wildlife, which put us at risk of pandemics because we are all globally connected through travel and trade." Wild animals on the edge of extinction are few in number and generally pose a low risk of passing on infectious diseases, said Dr Johnson, except where human exploitation and habitat loss puts them in close contact with humans. "Exploitation of wildlife, which has caused once abundant wildlife to decline in numbers, through hunting and trading in wildlife, have endangered species survival and also put humans at risk of emerging infectious disease," she said. Scientists have long drawn attention to human diseases that have originated in animals, including Sars, Mers and Ebola. In the wake of coronavirus, there is growing awareness that human health is linked both with animal health and the health of the planet as a whole.

4-8-20 Blood pressure drugs may do more harm than good for some older people
The idea that treating high blood pressure can sometimes do more harm than good has gained further support from a study of people over the age of 75 with the condition. This is because, contrary to expectations, people in this group who had high blood pressure had a lower risk of death than those with lower blood pressure. “Overall, blood pressure treatment is a good thing, but there are likely to be people in whom the risks outweigh the benefit,” says Jane Masoli at the University of Exeter, UK. Over the past few decades, the level at which blood pressure, which is measured in millimetres of mercury (mmHg), is classed as too high and needing treatment has fallen. Doctors used to recommend treatment to reduce blood pressure when it was more than 200/100 mmHg. Now the optimal blood pressure level is generally seen as between 120/80 and 90/60 mmHg. UK guidelines recommend treating someone over the age of 80 if their blood pressure is over 150/90 mmHg, and over 140/90 mmHg in people who are younger. In the US, the target has recently been lowered to 130/80 for all ages. Blood pressure varies over time and the medications that lower it can also cause harm. If these medicines lower blood pressure too much, this can cause dizziness and falls, which can be dangerous for older people. Masoli’s team looked at people who are more vulnerable to such harms but who are usually excluded from trials of blood pressure medicines: people who are 75 years old or more, and those who are frail or who have multiple health problems. The group tracked the health of about 400,000 people in the UK for 10 years. All participants were at least 75 years old when the study began. While those with a blood pressure above 150 mmHg had a higher rate of heart attacks and strokes than people whose blood pressure was lower during the study period, there were fewer deaths in that group overall. In people who were aged between 75 and 84 years old at the start of the study, the lowest risk of death from any cause was in those whose systolic blood pressure was between 140 and 170 mmHg – which would usually be classed as too high. And in those over 85, having blood pressure over 140 mmHg always carried a lower risk of death, no matter how high their blood pressure was.

4-7-20 Does the ACE2 protein explain covid-19 risk for underlying conditions?
Does a cell surface protein explain why the coronavirus is more likely to kill people with diabetes or heart disease? Researchers are trying to find out. DOES a protein on the surface of some of our cells explain why certain people are more at risk from covid-19? Studies of confirmed cases so far show that people with coronary heart disease or diabetes are more likely to die than other people if they catch the coronavirus. Individuals with lung disorders, such as chronic obstructive pulmonary disease (COPD), and smokers are also at greater risk, says Janice Leung at the University of British Columbia in Canada. As we begin to understand the virus better, focus is turning to a protein called ACE2. The coronavirus attaches to this receptor protein on the surface of our cells to gain entry to them. The protein is carried by cells in the nose, lungs and gut. It is possible that variation in how much of this protein people have may help explain why some are more likely to die from covid-19. When Leung and her colleagues looked at lung tissue samples from volunteers, they found that the cells of smokers and those with COPD make much more ACE2 (medRxiv, doi.org/dqx2). This may explain why these people are more likely to have severe covid-19 infections, says Leung. “If you ever needed another reason to stop smoking, this would be it,” she says. People with diabetes also seem to produce more ACE2. But we don’t know yet if ACE2 levels really do have an effect on coronavirus infections. The link between covid-19 deaths and diabetes and cardiovascular and heart conditions has led to some concern over ACE inhibitor drugs. These drugs, which are used to treat high blood pressure, coronary artery disease, heart failure and diabetes, work by targeting the ACE enzyme – a different protein, but one that works alongside ACE2 to regulate blood pressure. A study of 106 people with covid-19 by Yong Xiong at Zhongnan Hospital of Wuhan University, China, and his colleagues found that having hypertension, diabetes or cardiovascular disease was linked to patients clearing the virus from their bodies more slowly.

4-7-20 Stress early in life can make a child’s brain more like an adult's
Some children who experience stress in early life develop adult-like brain networks and show signs of ageing more slowly. These children also appear to take longer to progress through puberty, too. That is what Jonas Miller at Stanford University in California and his colleagues found when they tracked 214 children over two years. The youngsters, aged from 9 to 13 years at the start of the study, were asked whether they had witnessed or experienced a range of stressful experiences, such as a natural disaster, an accident or violence. At the same time, each child gave a saliva sample. Cells from the sample allowed Miller’s team to look at the length of telomeres – DNA caps at the end of chromosomes that shorten as we age. The children also had their brains scanned while they looked at images of adult faces expressing various emotions. Based on this, Miller and his colleagues analysed how the children’s amygdala interacted with the prefrontal cortex – the part of the brain known to control our behaviour, among other things. In children, the amygdala and prefrontal cortex tend to fire together. But adult brains show a different pattern – when the prefrontal cortex is active, it tends to damp down the activity of the amygdala. This is thought to be important for controlling our emotions. The children who reported experiencing more early life stress tended to show a more adult pattern of brain connectivity, the team found. And this pattern seemed to be associated with slower biological ageing. When the team looked at the children again two years later, those with more adult-like brain activity seemed to be progressing through puberty more slowly and their telomere shortening was blunted compared to their peers.

4-7-20 The PBS documentary ‘The Gene’ showcases genetics’ promise and pitfalls
The film, from executive producer Ken Burns, chronicles the crucial discoveries that have shaped the field. The genetic code to all life on Earth, both simple and complex, comes down to four basic letters: A, C, T and G. Untangling the role that these letters play in life’s blueprint has allowed scientists to understand what makes everything from bacteria to people the way they are. But as researchers have learned more, they have also sought ways to tinker with this blueprint, bringing ethical dilemmas into the spotlight. The Gene, a two-part PBS documentary from executive producer Ken Burns airing April 7 and 14, explores the benefits and risks that come with deciphering life’s code. The film begins with one of those ethical challenges. The opening moments describe how biophysicist He Jiankui used the gene-editing tool CRISPR/Cas9 to alter the embryos of twin girls who were born in China in 2018 (SN: 12/17/18). Worldwide, critics condemned the move, claiming it was irresponsible to change the girls’ DNA, as experts don’t yet fully understand the consequences. “This moment heralded the arrival of a new era,” narrator David Costabile says. “An era in which humans are no longer at the mercy of their genes, but can control and even change them.” The story sets the stage for a prominent theme throughout the documentary: While genetics holds incredible potential to improve the lives of people with genetic diseases, there are always those who will push science to its ethical limits. But the driving force in the film is the inquisitive nature of the scientists determined to uncover what makes us human. The Gene, based on the book of the same name by Siddhartha Mukherjee (SN: 12/18/16), one of the documentary’s executive producers, highlights many of the most famous discoveries in genetics. The film chronicles Gregor Mendel’s classic pea experiments describing inheritance and how experts ultimately revealed in the 1940s that DNA — a so-called “stupid molecule” composed of just four chemical bases, adenine (A), thymine (T), cytosine (C) and guanine (G) — is responsible for storing genetic information. Historical footage, in Burns’ typical style, brings to life stories describing the discovery of DNA’s helical structure in the 1950s and the success of the Human Genome Project in decoding the human genetic blueprint in 2003.

4-4-20 How immune responses weaken with age
As cases and deaths from the coronavirus pandemic rise, one trend remains consistent: The virus is deadliest for older adults. Eight in 10 Covid-19 deaths in the United States have been among adults 65 or older, according to a mid-March report from the Centers for Disease Control and Prevention. Older adults, of course, are more likely to have existing medical conditions and weakened respiratory systems — two major risk factors for becoming severely ill from infection by SARS-CoV-2, the virus that causes Covid-19. But scientists believe that another factor in the observed heightened risk is likely the general decline in the immune system that's seen with age. In medicine, it has long been known that older immune systems struggle to fight off infections. The ebbing of resistance to infectious disease with age is particularly clear when looking at studies of vaccines. During 2018–19, for example, the seasonal flu vaccine was effective for roughly three of every five children 17 and younger, according to the CDC. The same vaccine was effective for only about one of every four adults 50 and older. Scientists have rushed to start trials for a vaccine against SARS-CoV-2. But even when they succeed in developing an effective one, University of Pennsylvania immunologist Michael Cancro worries that any coronavirus vaccine may be less effective for older adults — just as current vaccines are for other diseases. "I doubt it'll be worse, I don't think it will be any better," says Cancro, who wrote about age-associated changes in the immune system in the most recent Annual Review of Immunology. Scientists are working hard to understand how age changes the immune system so that they can better protect seniors against current and future infectious diseases. It's a timely goal. By 2030, there will be more adults over 60 than children under 10, according to the United Nations. In addition to the current threat of Covid-19, influenza poses a serious risk to this age group: Nearly three of four people who died of flu during the 2018–19 season were 65 or older, according to the CDC.

4-4-20 Can plasma from recovered COVID-19 patients treat the sick?
Clinical trials will test if antibodies against the coronavirus prevent infection, aid survival. Since March 28, at least 11 patients critically ill with COVID-19 at hospitals in New York City and Houston became the first in the United States to receive a promising experimental treatment. But the therapy, newly authorized for emergency use by the U.S. Food and Drug Administration, wasn’t concocted in a pharmaceutical laboratory. It came from the blood of other patients, those who have recovered from the coronavirus infection. The treatment is convalescent plasma, the liquid component of blood taken from someone who has survived an infection, in this case COVID-19. With the United States now leading the world in confirmed cases of the disease — and no proven treatments yet — researchers here are racing to set up clinical trials to test how effective convalescent plasma is against SARS-CoV-2, the virus that causes COVID-19. If the treatment is beneficial, that could lead to FDA approval for wider use. A vaccine against SARS-CoV-2 is at best more than year away (SN: 2/21/20). In trying to manage COVID-19 over the next several months, the question is, “what kind of treatments could we administer that could truncate this pandemic?” says pathologist John Roback of Emory University School of Medicine in Atlanta, who does research on transfusion medicine. The top candidates are drugs already approved to treat diseases such as malaria that might be repurposed for COVID-19 (SN: 3/10/20) and convalescent plasma, he says. To fight a virus, the immune system develops antibodies, proteins that bind to parts of the virus and impede the infection. When a person makes antibodies in response to an infection or upon getting a vaccine, it’s called active immunity. The initial ramp up to antibody production can take about a week or two, but once that has occurred, the immune system will be able to quickly respond to the next exposure to the virus. For some viruses and vaccines, active immunity can last decades or even lifelong.

4-4-20 The noble lie about masks and coronavirus should never have been told
Just tell the complicated truth about coronavirus. hose of you of a certain age will doubtless remember a time when it was universally acknowledged that wearing masks would not protect you or anyone else from the coronavirus pandemic. By "certain age" here I mean all living Americans born on or before April 1, 2020, which according to my notes is when it became possible to express a contrary position in polite society. This was always nonsense. The White House is now suggesting that all of us should wear masks whenever we leave our houses. We are even stealing vast stockpiles of them from the Germans, who have been wearing them in public for around a month on the rather more numerous occasions when their leaders exempt them from house arrest. People who can't get proper masks (apparently the kind people wear when they spray for bugs) are being encouraged to make their own. If nothing else, this has given tedious DIY addicts something else to be self satisfied about. No one cares how quaint and interesting you think the piece of cloth meant to protect you from a disease is, okay? Whether the journalists and other apparent experts who enthusiastically spread this apparent lie about masks knew it was false is very much an open question. Some of us found it odd that the same people were also saying that masks should be reserved for use by medical professionals. If masks don't do anything, why do doctors and nurses need them? Are they an ornamental part of a dress uniform? The mind reels. Regardless of the personal honesty of those involved in it, this propaganda campaign should never have been conducted in the first place. It is one thing to debate what should be empirical questions, such as the efficacy of wearing protective equipment in an attempt to forestall the spread of viral infections; it is another for people to bang on about whatever the latest current corona wisdom is with the same tedious certainty that not long ago made us a nation of Logan Act scholars and experts on the non-existent criminal law implications of the emoluments clause. These manias do roughly as much for public health as those kids — there was at least one in every first-grade class — who relentlessly ssshh everyone else in line do to improve schoolyard behavior.

4-3-20 Experimental diabetes device works by killing gut cells with hot water
A bizarre diabetes treatment seems to destroy cells lining the gut to change people’s hormonal response to food. The technique involves putting a tube down someone’s throat and into the first part of their small intestine, called the duodenum, while they are sedated. Known as Revita, the procedure uses water heated to 75°C to kill the outermost layer of cells. People with type 2 diabetes, which is linked with being overweight, often have overgrowth of the cells lining the duodenum. This may result from years of unhealthy eating, says Harith Rajagopalan at Fractyl, the firm behind the procedure. When we eat, cells in the duodenum make a hormone called gastric inhibitory polypeptide (GIP), which triggers several other hormones that control how we metabolise nutrients. GIP production is enhanced in people with diabetes. Killing some of the excess gut cells should make the person’s hormonal response to food more like that of someone without diabetes, he says. To date, about 300 people in the UK, three other European countries and Brazil have had the intervention. Of these, 34 people have been studied for two years, and their levels of HbA1c, a marker of long-term blood glucose levels, fell from 8.5 to 7.5 per cent. Despite this improvement, the people would still be classed as having diabetes. In a randomised 70-person trial, where half the participants had a sham version of the treatment, those who got the real thing had improvements in glucose control and markers of liver health after three months. The figures were due to be presented at the Endo 2020 conference in San Francisco last week, which was cancelled. The procedure tends to result in a small weight loss of about 3 kilograms, but it won’t be marketed as a treatment for obesity. “It’s a metabolic reset rather than a weight loss procedure,” says Rajagopalan. If people continue eating an unhealthy diet afterwards, their gut cells may overgrow again but that is likely to take several years, he says. “This procedure could be repeated in time if necessary.”

4-3-20 Why we still don't know what the death rate is for covid-19
What are your chances of dying if you get infected by the coronavirus? Despite data pouring in from many countries, there’s still a wide range of estimates, from as few as 1 in 1000 to as many 1 in 30. What is clear is that there is no one answer: the risk depends on your age, your sex, your health and the care you receive if you become severely ill. In other words, death rates will vary from place to place and over the course of the pandemic. In the UK, as of 2 April, 2921 people had died out of 33,718 confirmed cases – a crude case fatality rate of around 9 per cent. For Italy, the figure is nearly 12 per cent and for Germany just 1 per cent. These figures do not tell us what we really want to know: how many of those infected will die as a result, which is known as the infection fatality rate. Crude case fatality rates are so-called because they do not take into account the fact that some of those who have tested positive will go on to die. Early in March, for instance, South Korea had a crude case fatality rate of just 0.6 per cent. That has risen to 1.7 per cent. Among resolved cases – those who have died or recovered – the case fatality rate is 2.9 per cent. The differences between countries are also partly to do with how many elderly people have been infected, says Melinda Mills at the Leverhulme Centre for Demographic Science in the UK. In South Korea and Germany, it was mostly younger people infected at first. Based on what’s happening in Italy, Mills and colleagues calculate that if 10 per cent of people were infected, there would be 302,530 deaths in Italy in with its ageing population of 61 million – but just 142,058 deaths in Nigeria with its much younger population of 191 million. The big question is how many infected people with mild or no symptoms are being missed. If lots are, the infection fatality rate will be much lower than the case fatality rate. We know the UK is testing only severely ill people and missing lots of mild cases, but South Korea and Germany have been testing more widely.

4-3-20 Just breathing or talking may be enough to spread COVID-19 after all
Experts had said that the virus spreads only through large droplets from a cough or sneeze. The coronavirus that causes COVID-19 may spread through the air in tiny particles that infected people exhale during normal breathing and speech. Until now, experts have said that the virus, called SARS-CoV-2, doesn’t spread through the air in that way, but rather through relatively large droplets released when people cough or sneeze. Those droplets can contaminate surfaces or objects and infect people who touch the surface and then touch their faces. Large droplets are still a means of infection, but researchers now say that tiny airborne particles may also carry infectious virus. “Currently available research supports the possibility that SARS-CoV-2 could be spread via bioaerosols generated directly by patients’ exhalation,” researchers from the U.S. National Academies of Science, Engineering and Medicine wrote in an April 1 report to the White House Office of Science and Technology Policy. If the coronavirus is airborne, that could help explain why it is so contagious, and can spread before people have symptoms (SN: 3/13/20). As of April 2, more than 1 million people worldwide are confirmed to have COVID-19, with nearly a quarter of those cases in the United States, according to tracking by Johns Hopkins University. More than 50,000 people have died worldwide, including more than 5,600 people in the United States. Wearing surgical masks can cut down on the amount of virus that infected people spread, the expert panel says, citing an unpublished study from the University of Hong Kong. The letter does not address whether wearing a mask will protect the person wearing the mask from catching the illness (SN: 3/27/20). How much virus a person must breathe in to get infected isn’t known.

4-3-20 Southern Africa may have hosted a hominid transition 2 million years ago
Cave excavation yields braincases from both Homo erectus and Paranthropus robustus. Members of three different hominid lines clustered at the bottom of Africa around 2 million years ago, signaling an evolutionary swing propelled by the spread of a highly successful, humanlike species, new fossil discoveries suggest. It’s unclear, though, if the three ancient populations inhabited the region at precisely the same time. Excavations at Drimolen, a set of caves in South Africa, uncovered two fossil braincases, one from Homo erectus and the other from Paranthropus robustus, say paleoanthropologist Andy Herries of La Trobe University in Melbourne, Australia, and his colleagues. Both finds date to between 2.04 million and 1.95 million years ago, the scientists report in the April 3 Science. The H. erectus fossil comes from a child who displayed a long, low braincase typical of adults from that species. The P. robustus braincase is that of an adult. Researchers previously determined that two Australopithecus species, A. africanus and A. sediba (SN: 7/25/13), inhabited nearby parts of South Africa approximately 2 million years ago. Taken together, these discoveries indicate that a major transition in hominid evolution occurred in southern Africa between around 2.1 million and 1.9 million years ago, Herries’ team says. During that stretch, climate and habitat fluctuations drove Australopithecus species to extinction. H. erectus and P. robustus weathered those ecological challenges, possibly outcompeting Australopithecus for limited resources, the researchers speculate. It’s unclear whether members of the three hominid lines ever encountered each other during that transition period. “These spectacular discoveries confirm what some of us have expected for some time, that three genera of [hominids] coexisted in southern Africa,” says paleoanthropologist Darryl de Ruiter of Texas A&M University in College Station, who was not involved in the research.

4-2-20 Diet and exercise will keep your brain young – depending on your genes
Will a regular exercise routine and a healthy diet keep your brain young? It depends on your genes. People who have certain forms of genes that play a key role in brain ageing seem to respond better to healthy lifestyle interventions. These make it “more likely that exercise or adhering to a Mediterranean diet will have a greater impact on your cognitive ageing,” says Sandrine Thuret at King’s College London. Cognitive ageing is thought to rely on neural stem cells in the brain’s hippocampus which continue to produce new neurons throughout life, and are thought to play an important role in forming new memories. Research in rodents suggests that as we get older, these cells make fewer and fewer neurons – and this seems to be linked to lower cognitive skills in later life. To better understand this link, and how it might impact human brain ageing, Thuret and her colleagues studied 19 genes that are known to be linked to ageing in neural stem cells. “We know from animal studies that these genes are altered during ageing,” says Thuret. The team analysed how these genes changed in their expression in human neural stem cells as the cells age. A set of lab experiments revealed that nine of these genes appear to change depending on whether the cells are young or old, suggesting they are involved in ageing. To find out if the genes play a role in cognitive ageing, Thuret’s team then looked for variations in these genes in people. The group collaborated with other scientists studying pairs of adult twins. Each twin kept a food diary, and had their physical activity monitored using a wrist-worn fitness tracker. They also underwent cognitive tests, which scored their memory and ability to learn. Thuret and her colleagues also looked for variations in the nine genes they had already singled out. The team found two genes that seem to be linked to a person’s cognitive performance, depending on which form of the gene a person has. The effect of one of these genes, SIRT1, which is already heavily investigated in ageing research, seems to depend on the level of exercise a person takes. Another gene, GRB10, also plays a role – but it depends on whether or not the person follows a Mediterranean diet, says Thuret.

4-2-20 Three human-like species lived side-by-side in ancient Africa
Two million years ago, three different human-like species were living side-by-side in South Africa, a study shows. The findings underline a growing understanding that the present-day situation, where one human species dominates the globe, may be unusual compared with the evolutionary past. The new evidence comes from efforts to date bones uncovered at a cave complex near Johannesburg. The research has been published in the journal Science. The new work also revealed the earliest known example of Homo erectus, a species thought to be a direct ancestor of modern humans (Homo sapiens). The three groups of hominins (human-like creatures) belonged to Australopithecus (the group made famous by the "Lucy" fossil from Ethiopia), Paranthropus and Homo - better known as humans. Andy Herries, from LaTrobe University in Melbourne, Australia, and colleagues evaluated remains found at the Drimolen Cave Complex using three different scientific dating techniques: electron spin resonance, palaeomagnetism and uranium-lead dating. "We collated all of the dates from each of these techniques and together they showed that we had a very precise age. We now know that the Drimolen Main Quarry and all of the fossils in it are dated from 2.04 to 1.95 million years ago," said co-author Stephanie Baker, from the University of Johannesburg. The Drimolen complex has produced multiple ancient fossils over the years, including those of ancient hominins. But a few years ago, researchers uncovered two new skullcaps. One of these belonged to the relatively primitive species Paranthropus robustus. The other was more modern in appearance and was identified as Homo erectus. They named the H. erectus skullcap DNH 134. Homo erectus is one of our direct human ancestors and may have been the first early human species to migrate out of Africa into the rest of the world. Not only is this the earliest example of the species anywhere in the world, but it's the only specimen known from South Africa.

4-2-20 How large a gathering is too large during the coronavirus pandemic?
The math of social networks can create a roadmap to a group size that still curbs spread. A question has perplexed public officials trying to curb the COVID-19 pandemic: How large of a group of people is too large? As the spread of the coronavirus has gathered speed, U.S. officials urged limits on large gatherings, constantly scrambling to reduce the definition of “large.” First, meetings of more than 1,000 were discouraged, then 250, 100, 50 and 10. As many states institute orders to stay at home, all nonessential gatherings are being banned. But no scientific rationale has been cited for any particular number. Getting the right answer is crucial. Too large and you don’t control the epidemic. Too small, and people’s lives and livelihoods may be upended, for insufficient social benefit. “I am not aware of any quantitative modeling informing those decisions,” says Lydia Bourouiba, a physicist and epidemiologist at MIT. “They weren’t based on events.” Now, a new study is providing one roadmap for coming up with an answer. There is no gathering size that can eliminate all risk. But there is a threshold between curbing the epidemic and having it spread like wildfire, and that number is most likely not zero, the researchers conclude. The finding could have implications not only for slowing the pandemic, but also for figuring out how to eventually return to normal life without causing a new surge in cases (SN: 3/24/20). In the study, posted online March 12 at arXiv.org, five epidemic modelers showed mathematically how an epidemic can be controlled without banning all get-togethers. Their model includes a version of the “friendship paradox,” which says that your friends in a social network on average have more friends than you. When an epidemic strikes such a network, large gatherings are especially bad because they attract people who have more contacts than average — and hence are more likely to already be infected.

4-2-20 Coronavirus: Expert panel to assess face mask use by public
Should more of us wear face masks to help slow the spread of coronavirus? This question is to be assessed by a panel of advisers to the World Health Organization (WHO). The group will weigh up research on whether the virus can be projected further than previously thought; a study in the US suggests coughs can reach 6m and sneezes up to 8m. The panel's chair, Prof David Heymann, told BBC News that the new research may lead to a shift in advice about masks. The former director at the WHO explained: "The WHO is opening up its discussion again looking at the new evidence to see whether or not there should be a change in the way it's recommending masks should be used." The WHO recommends keeping a distance of at least 1m from anyone coughing or sneezing to avoid the risk of infection. It says people who are sick and show symptoms should wear masks. It emphasises that masks are only effective if combined with frequent hand-washing and used and disposed of properly. The UK, along with other countries including the US, advises that social distancing should mean staying at least 2m apart. This advice is based on evidence showing that viruses can only be transmitted while carried within drops of liquid. The understanding is that most of those drops will either evaporate or fall to the ground near to the person who released them. Researchers at the Massachusetts Institute of Technology (MIT) in Cambridge, US, used high-speed cameras and other sensors to assess precisely what happens after a cough or sneeze. They found that an exhalation generates a small fast-moving cloud of gas that can contain droplets of liquid of varying sizes - and that the smallest of these can be carried in the cloud over long distances. The study - conducted in laboratory conditions - found that coughs can project liquid up to 6m away and that sneezes, which involve much higher speeds, can reach up to 8m away. The scientist who led the study, Prof Lydia Bourouiba of MIT, told me that she is concerned about the current concept of "safe distances". "What we exhale, cough or sneeze is a gas cloud that has high momentum that can go far, traps the drops of all sizes in it and carries them through the room," she said. "So having this false idea of safety at one to two metres, that somehow drops will just fall to the ground at that distance is not based on what we have quantified, measured and visualised directly."

4-2-20 Hunt for George Clooney's face explains how stress affects decisions
Stress can lead to poor decision making, and people hunting for George Clooney’s face could help us understand why. Thackery Brown at Stanford University and his colleagues asked 38 people, with an average age of 23, to navigate looping paths around 12 different virtual towns in a simulated environment. Each town had just a few streets and took about a minute to navigate. The researchers also placed the face of a celebrity – George Clooney, for example – at one point along the route. The team then asked the participants to navigate the simulation while lying inside an fMRI machine. This time, participants began in an unfamiliar location in the virtual town and had to navigate the streets to find the celebrity face as fast as possible. In order to test the effects of stress, 20 of the participants also wore a device on their ankle that gave them mild electric shocks at random intervals. The team also monitored the levels of cortisol, a stress hormone, in all 38 people. Before doing so, they were each given a few seconds to mentally plan their route. Each town was designed so that a previously unused shortcut was the most effective way to reach the celebrity. The towns were small enough that people should have been able to work this out but those wearing the ankle device took the shortcut less often: 31 per cent of the time versus 47 per cent of the time for those without. They were also more stressed, with elevated cortisol levels, and were 20 per cent slower to reach the celebrity. The researchers also used a machine learning algorithm to decode the fMRI data of each participant, training it to identify when a person was looking at a particular face or landmark in the virtual town. They then used the AI to try to work out what the participants were thinking about when planning their route. Non-stressed participants were more likely to imagine all of the landmarks present along the route that they went on to take, while stressed participants appeared to focus on just the landmarks closest to their starting point. This links into how stress affects us in the real-world, says Brown. “When something is really stressing out, we stop making plans and just worry about the thing in front of us,” he says. “Looking at the neural mechanisms of stress on memory may contribute to how we prepare for stressful events,” says Neil Burgess at University College London. “Or how we deal with conditions like PTSD.”

4-2-20 This 300,000-year-old skull may be from an African ‘ghost’ population
The Broken Hill fossil’s age suggests the hominid lived at the same time as Homo sapiens. A mysterious but well-preserved hominid skull found nearly a century ago comes from a population that lived in Africa around 300,000 years ago, as the earliest Homo sapiens were evolving, a new study finds. This discovery indicates that a separate Homo population, perhaps a species some researchers call H. heidelbergensis (SN: 6/22/19), inhabited Africa at the same time as both H. sapiens and a recently discovered population dubbed H. naledi (SN: 6/10/17), say geochronologist Rainer Grün and his colleagues. African H. heidelbergensis could have been a recently reported “ghost population” (SN: 3/14/20) that interbred with ancient H. sapiens and passed a small amount of DNA to present-day West Africans, the researchers suggest April 1 in Nature. “We can now identify at least three distinct and contemporary [Homo] lineages in Africa about 300,000 years ago, but we don’t yet know whether our ancestry was largely or entirely contained within the H. sapiens part of that variation,” says paleoanthropologist and study coauthor Chris Stringer of the Natural History Museum in London. Researchers have puzzled over the age of the Broken Hill skull since its 1921 discovery in south-central Africa. Metal ore mining at what was then Northern Rhodesia’s Broken Hill mine revealed deposits bearing the skull and two associated leg fossils. The site, located in what’s now known as Zambia, has been named Kabwe. Previous age estimates for the fossils, based on clues such rodent fossils and stone tools found at the site, have ranged widely from around 500,000 to 125,000 years old. Because quarrying destroyed the site, sediment that may have yielded fossils can’t be dated. Instead, Grün, of Griffith University in Nathan, Australia, and his team dated small samples of bone and teeth from the Broken Hill skull using measures of the radioactive decay of uranium and the accumulation of natural radioactivity from sediment and cosmic rays. Based on these techniques, the team estimates the skull’s age at between 324,000 and 276,000 years old.

4-2-20 Lucy’s species heralded the rise of long childhoods in hominids
Prolonged brain growth was already a feature for hominids before Homo genus members appeared. Lucy’s kind had small, chimplike brains that, nevertheless, grew at a slow, humanlike pace. This discovery, reported April 1 in Science Advances, shows for the first time that prolonged brain growth in hominid youngsters wasn’t a by-product of having unusually large brains. An influential idea over the last 20 years has held that extended brain development after birth originated in the Homo genus around 2.5 million years ago, so that mothers — whose pelvic bones and birth canal had narrowed to enable efficient upright walking — could safely deliver babies. But Australopithecus afarensis, an East African hominid species best known for Lucy’s partial skeleton, also had slow-developing brains that reached only about one-third the volume of present-day human brains, say paleoanthropologist Philipp Gunz of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and his colleagues. And A. afarensis is roughly 3 million to 4 million years old, meaning slow brain growth after birth developed before members of the Homo genus appeared, perhaps as early as 2.8 million years ago (SN: 3/4/15). Too few A. afarensis infants have been studied to calculate the age at which this species attained adult-sized brains, Gunz cautions. The brains of human infants today reach adult sizes by close to age 5, versus an age of around 2 or 3 for both chimps and gorillas. In the new study, Gunz and colleagues estimated brain volumes for six A. afarensis adults and two children, estimated to have been about 2 years and 5 months old. The kids had brains that were smaller than adult A. afarensis brain sizes in a proportion similar to human children’s brains at the same age relative to adult humans. The new data suggest that, for Lucy’s species, “infant brain size [relative to that of an average adult] may have been proportionally even smaller than in human infants,” says biological anthropologist Zachary Cofran of Vassar College in Poughkeepsie, N.Y., who did not participate in the new study. If so, that pattern would strongly point to an extended period of brain growth for A. afarensis.

4-2-20 Roughly 90 million years ago, a rainforest grew near the South Pole
High atmospheric carbon dioxide levels and an ice-free Antarctica may explain how. Once upon a time, there was a swampy rainforest near the bottom of the world. Buried sediment extracted from the seafloor off West Antarctica contains ancient pollen, fossilized roots and other chemical evidence of a diverse forest that flourished millions of years ago, less than a thousand kilometers from the South Pole. The sediment offers the southernmost glimpse yet into just how warm Earth was during the mid-Cretaceous Period, between 92 million and 83 million years ago. By analyzing traces of vegetation in the sediment, researchers reconstructed climate conditions at the site. Average annual temperatures in the forest were about 13° Celsius, with summertime temperatures reaching as high as 20° or 25° C, the team reports in the April 2 Nature. The mid-Cretaceous is known to have been one of the warmest periods on Earth in the last 140 million years, based on analyses of fossils and sediment collected from the seafloor closer to the equator. Atmospheric carbon dioxide levels are thought to have been at least 1,000 parts per million. (Today’s atmospheric carbon dioxide levels average around 407 ppm, the highest in the last 800,000 years.) But for a forest to thrive so far south, even more potent greenhouse conditions must have existed than previously thought, with atmospheric carbon dioxide levels between 1,120 and 1,680 ppm, says marine geologist Johann Klages. “It shows us the extreme potency of carbon dioxide — what carbon dioxide can really do,” says Klages, of the Alfred Wegener Institute in Bremerhaven, Germany. “Even without light for four months, [Antarctica] could still have a temperate climate.” The team retrieved the 30-meter-long core from within the Amundsen Sea Embayment, where today fast-melting Thwaites and Pine Island glaciers drain into the sea (SN: 1/7/20). Even before analyzing the core, Klages says, the researchers knew it was special: The bottom three meters of sediment, corresponding in time to the mid-Cretaceous Period, showed traces of roots.

4-1-20 How to get the health benefits of nature when you’re stuck inside
Going out into the natural world is good for your health and mind, and you can still get some of the same benefits even when stuck inside, says Graham Lawton. LAST week, during what already feels like the halcyon days of Before Lockdown, a wonderful package came through my letterbox. It contained the Great Trees of London Map, which lists the UK capital’s 50 most interesting trees. Did you know there is a giant redwood towering over New Cross Gate tube station? Or a yew in Totteridge that has been there since before the Norman Conquest? I was planning to visit them all. That will now have to wait. I have written before about London’s green spaces and its status as a national city park. One of the pleasures of living here is the wealth of urban nature on our doorsteps. I miss it. This isn’t just the frustration of enforced confinement because of the coronavirus. A ton of research tells us that contact with nature has significant health benefits. Luckily, there are a few simple tricks you can use to get some of the benefits of nature while sticking to the rules about social isolation. Here is why it is so important. Last year, a study found that spending just 2 hours a week in green spaces boosts physical and mental well-being by about the same amount as getting enough exercise. There are other positives to be had. People who take time to connect with nature are more likely to engage in pro-environmental behaviour and care about the natural world. Many small studies have found this link, and now a very big one has confirmed it. The study recruited more than 24,000 adults in England and asked how much contact they had with nature. The researchers also asked about pro-environmental behaviours including recycling, buying eco-friendly products, walking or cycling and belonging to green groups. They found that the more often people visited nature for recreation, the greater their pro-environmental behaviour and appreciation of the natural world.

4-1-20 Diets do help you lose weight - but the benefits usually don't last
Atkins, Paleo or Zone – whichever diet you follow, you will only lose a bit of weight, and improvements to your blood pressure and cholesterol will disappear within a year. That is according to a comparison of randomised clinical trials assessing the effects of 14 popular branded diets. “We chose the categories of diets that are most widely advertised and that are in the public mind,” says Gordon Guyatt at McMaster University in Canada, who led the research. Guyatt and his colleagues found 121 trials of such diets, together including nearly 22,000 volunteers who were either overweight or obese, and had an average age of 49. Each trial compared the results of adults who were on the diet with others who ate as they usually did. The team looked for evidence of the diets’ effect on weight loss and markers of cardiovascular health, including blood pressure and cholesterol. All of the diets resulted in some weight loss. Six months after starting a diet, volunteers were, on average, about 4 kilograms lighter. There were also improvements in blood pressure and cholesterol at this point: levels of harmful LDL cholesterol were lower, while there was more of the beneficial HDL form. The team noted some small differences in the effects of the diets. The Mediterranean diet appeared to have the biggest impact on cholesterol, for example, and low-fat diets also improved cholesterol to a greater degree than other diets. The Atkins diet seemed to result in the most weight loss at six months. But 12 months into a diet, the effects had mostly disappeared. By this point, the volunteers had gained back most of their lost weight, and the benefits relating to blood pressure and cholesterol had vanished. “People can lose appreciable amounts of weight in the short term, and weight loss is associated with a decrease in risk factors,” says Guyatt. “However, with time, people tend to gain the weight back, and in 12 months there’s no benefit in terms of blood pressure and cholesterol.” Volunteers may have struggled to maintain their diets, says Guyatt. “The fact that they lost weight early and much of it was regained suggests that adherence to the diet was much better in the first six months,” he says.

4-1-20 Human evolution: The astounding new story of the origin of our species.
Forget the simple out-of-Africa idea of how humans evolved. A huge array of fossils and genome studies has completely rewritten the story of how we came into being. JEBEL IRHOUD, Morocco, 1961. In a barium mine in the foothills of the Atlas mountains, a miner makes a ghoulish discovery: a near-complete human skull embedded in the sediment. Archaeologists called in to investigate find that the skull is old, but not that old. It is filed away and largely forgotten. Hinxton, UK, 2019. Robert Foley, a palaeoanthropologist at the University of Cambridge, is giving the opening address at a three-day conference on human evolution. “What I’m pretty sure of is that, by the end of the first day, something like 20 per cent of what I say will be wrong,” he says to the hall. “By the end of the second day, something like 50 per cent will be wrong, and at the end of the conference, I’m hoping that something I said at the beginning still holds true.” Until recently, the story of our origins was thought to be settled: Homo sapiens evolved in eastern Africa about 150,000 years ago, became capable of modern behaviour some 60,000 years ago and then swept out of Africa to colonise the world, completely replacing any archaic humans they encountered. But new fossils, tools and analyses of ancient and modern genomes are tearing apart that neat tale. The Jebel Irhoud skull has turned out to be a key to a new, slowly emerging paradigm. With the dust yet fully to settle, the question now is how many, if any, of our old assumptions still hold. “Should we be thinking of a completely different model?” asks Foley. “Abandoning out-of-Africa?” Strap in, it’s going to be quite a ride. The out-of-Africa paradigm to which Foley refers has become so entrenched that it is easy to forget how new it is. For decades before its emergence, human origins research was dominated by the early characters in the story: Homo erectus, for example, including “Peking Man”, unearthed in 1929; or Australopithecus afarensis, the famous “Lucy” discovered in Ethiopia in 1974. There was some debate about where modern humans appeared, and ideas were floating around of a recent African origin, but the fossil record seemed to support a model called multiregionalism. This argued that archaic humans were distributed across Africa and Eurasia at least a million years ago and evolved in parallel into modern humans.

4-1-20 Europe’s cave bears may have died out because of their large sinuses
The huge cave bears that once roamed Europe may have gone extinct because their large sinuses made it difficult to adapt their diet during a severe cold snap. Cave bears (Ursus spelaeus), which weighed up to 1000 kilograms and had a plant-based diet, went extinct 24,000 years ago when temperatures plummeted during the last glacial maximum. Scientists have speculated that the bears died out because the colder climate depleted food availability or they were driven to extinction by prehistoric humans. But one mystery is why closely related brown bears (Ursus arctos) managed to survive the same conditions. Alejandro Pérez-Ramos at the University of Malaga in Spain and his colleagues took CT scans of the skulls of four extinct cave bears and eight living bear species, including brown bears, and used them to create computer simulations of the bears’ different chewing styles. They found that cave bears had large sinuses that shaped their skulls in such a way that they could only chew with their back teeth. The researchers argue that this may explain why cave bears went extinct when the climate cooled and plant food ran low, because they couldn’t switch to eating meat, which normally requires the use of the front teeth. Compared to cave bears, brown bears had smaller sinuses and greater skull flexibility for chewing with their front or back teeth. This may be why they survived: they could eat plants or meat, says Pérez-Ramos. So why did cave bears evolve large sinuses in the first place? They may have helped the bears hibernate for longer, which would have carried advantages as winters started to stretch out during the last glacial period, says Pérez-Ramos. Sinuses are hollow cavities inside the head that act as reservoirs for gases like nitric oxide and hydrogen sulphide, which activate hibernation in some bears by lowering their heart rate and body temperature. However, being constrained to a plant-based diet meant the bears probably couldn’t fatten themselves up enough to survive the increasingly long and extreme winters, and may have starved to death as they hibernated, says Pérez-Ramos. In other words, the development of large sinuses may have been a “fatal trade-off”, he says.

4-1-20 The hunt for patient zero: Where did the coronavirus outbreak start?
Growing evidence suggests the covid-19 outbreak may not have started at Wuhan’s Huanan Seafood Market in December after all. Finding its origins may help us stop it happening again. AS THE world fights to tackle the covid-19 pandemic, a mystery remains: how and when did the virus cross over into humans? Doubt has been cast on the idea that it happened in the Huanan Seafood Market in Wuhan, China, in December, and now researchers are trying to identify the real source of the infection. The hope is that this knowledge could help prevent future pandemics of other new coronaviruses. According to a study of the first 41 people hospitalised with covid-19 published in January (The Lancet, doi.org/ggjfnn), the first case of covid-19 was a man who showed symptoms on 1 December 2019. Unlike the majority of early cases, he had no links to the Huanan Seafood Market. Since then, no one has been able to confirm where he caught the virus, or if he was even the first person to contract it. Another January analysis, of the first 425 covid-19 cases, conducted by the Chinese Center for Disease Control and Prevention and China’s National Health Commission, placed the first confirmed case a week later, on 8 December. But subsequent evidence hints that the outbreak probably began before December. Viral genome analyses suggest that the virus jumped from animals to humans in November (The Lancet, doi.org/ggp6gz), but it could have happened as early as late September (Journal of Medical Virology, doi.org/ggjvv8). This is consistent with the South China Morning Post report on Chinese government documents that suggested the earliest case of covid-19 may have been a 55-year-old person from Hubei province who seems to have contracted the virus on 17 November. The first cases to be flagged, in December, were reported by Wuhan doctors using a surveillance protocol designed to pick up pneumonias with unknown causes. The system was set up after the 2002-2003 SARS outbreak, to detect new viruses.

4-1-20 Coronavirus: Are loss of smell and taste key symptoms?
A loss of smell or taste may be a sign that you have coronavirus, according to UK researchers. A team at King's College London looked at responses from more than 400,000 people reporting suspected Covid-19 symptoms to an app. But loss of smell and taste are also signs of other respiratory infections, such as the common cold. And experts say fever and cough remain the most important symptoms of the virus to look out for and act upon. If you or someone you live with has a new continuous cough or high temperature, the advice is stay at home to stop the risk of spreading coronavirus to others. The King's College researchers wanted to gather information on possible coronavirus symptoms to help experts better understand and fight the disease. Of those reporting one or more symptoms of coronavirus to the Covid Symptom Tracker app: 1. 53% said they had fatigue or tiredness. 2. 29% persistent cough. 3. 28% shortness of breath. 4. 18% loss of sense of smell or taste. 5. 10.5% suffered from fever. Of these 400,000 people, 1,702 said they had been tested for Covid-19, with 579 receiving a positive result and 1,123 a negative one. Among the ones who had coronavirus infection confirmed by a positive test, three-fifths (59%) reported loss of smell or taste. Should loss of smell and taste be added to the key symptoms to watch out for? Experts say there's not enough evidence yet. Public Health England and the World Health Organization have not added them to the list. ENT UK, the body that represents Ear, Nose and Throat doctors, says it is not surprising that some patients with coronavirus might report these as symptoms, but they are not specific to Covid-19. They advocate including them as possible coronavirus symptoms. The King's researchers say loss of smell and taste might be useful extra symptoms to watch for, perhaps not on their own but alongside other important ones like cough and fever. Lead researcher Prof Tim Spector said: "When combined with other symptoms, people with loss of smell and taste appear to be three times more likely to have contracted Covid-19 according to our data, and should therefore self-isolate for seven days to reduce the spread of the disease."

4-1-20 Will the spread of covid-19 be affected by changing seasons?
In the northern hemisphere, as winter ends, cases of seasonal flu dwindle. Could the same happen with covid-19? Flu surges in winter for three reasons. First, the virus is more stable in cold, dry conditions with low levels of ultraviolet light. Second, people spend more time together indoors, which facilitates viral spread. Third, our immune systems may be weakened due to the mild vitamin D deficiency a lack of sunlight can cause. In theory, these factors could also cause the covid-19 virus to dampen down in spring. But we don’t know if this will happen, and the evidence so far is conflicting. In the first study to look at the effect of weather on covid-19, posted online in February, researchers at Harvard University looked at the effects of temperature and humidity on the virus’s transmission in China, Thailand, Singapore, Japan, South Korea and Taiwan, based on weather reports and data on covid-19 incidence between 23 January and 10 February. They found no significant difference in transmission rates between cold and dry provinces of China and tropical ones, as well as Singapore, concluding that higher temperature and humidity “will not necessarily lead to declines in case counts”. However, another study appeared the next day, which analysed data from Wuhan, the Chinese city where the coronavirus emerged. Alarmingly, it found that the virus seems to spread better in summery weather, with an optimum temperature of 19°C, humidity of 75 per cent and less than 30 millimetres of monthly rain. Even more worryingly, the researchers found that cold air destroys the virus. They recommended that, as the weather warms, containment measures should be ramped up. Since then, at least eleven similar studies have been posted online. Most have found the opposite. For example, one analysis looked at all 80,981 cases of covid-19 across mainland China between 20 January and 29 February. It found that the optimum temperature for virus transmission is 10°C, and that lower or higher temperatures suppress it. It found no link at all to humidity.

4-1-20 We may now know what our common ancestor with Neanderthals looked like
Two studies of ancient humans have shed new light on the last common ancestor we share with Neanderthals. An extinct species that was once in the frame now looks unlikely to be the one. Another now seems more plausible, but it may only be related to the ancestor. “My guess is we haven’t found the common ancestor yet,” says Chris Stringer of the Natural History Museum in London. However, the new findings clarify what the common ancestor may have looked like. Stringer’s team studied a skull called Kabwe 1, which was discovered in 1921 by miners at Broken Hill in what is now Zambia. “It was the first important [hominin] fossil found in Africa,” says Stringer. It probably belonged to a young male and had a primitive-looking face with “huge brow ridges over the eyes”. Many anthropologists place Kabwe 1 in Homo heidelbergensis, which ranged across Africa and Europe. It has long been a candidate for the common ancestor of three later groups: modern humans (Homo sapiens), the Neanderthals of Europe and west Asia, and the Denisovans of east Asia. However, until now the Kabwe skull’s age has been a mystery. The normal approach is to date the surrounding sediments, says Rainer Gru¨n of Griffith University in Australia. But the skull was found by accident and the site quarried, so researchers have no sediments to test. “The only thing we could do is to analyse the skull itself,” says Gru¨n. This is only now possible. Older methods would have required drilling into the skull, causing “unacceptable” damage. Instead, the team used lasers to remove fragments a quarter of a millimetre thick. Analyses of these fragments indicate Kabwe 1 is about 299,000 years old. “It’s pretty incredible that the new techniques they’re coming up with allow us to go back and directly date the fossils themselves,” says Shara Bailey of New York University.

4-1-20 Tiny bird-like dinosaur discovered in amber might actually be a lizardK
A fossilised skull trapped in amber that was recently identified as belonging to a tiny bird-like dinosaur might actually belong to a lizard. Last month, palaeontologists analysed an ancient skull that had been preserved in amber and concluded that it probably came from a tiny, humming bird-like dinosaur that lived 99 million years ago. Now, a different group of researchers have reanalysed the fossil and believe that it actually came from a lizard. Jing Lu at the Chinese Academy of Sciences and colleagues asked for copies of the CT scans from the original study, and reanalysed the data. They argue that certain features of the skull, particularly the structure of the teeth and the shape of the eye socket, are much more consistent with lizard rather than bird or dinosaur anatomy. Whereas dinosaurs characteristically have teeth that develop in tooth sockets, the teeth of this creature, named Oculudentavis khaungraae by the team that first analysed its skull, are fused together – a feature much more typical of lizards, according to Lu and colleagues. The authors of the original paper that described the fossil had attributed this to the miniaturisation of the animal, which has a skull measuring a mere 1.4 centimetres across. But Lu’s group argues that there is no evidence to suggest that miniaturisation would lead to these morphological changes. The structure of the bone behind the eye sockets of O. khaungraae is also consistent with eyes of a typical lizard shape, Lu and colleagues told New Scientist. Labelling the species as bird-like makes its small body size and other features appear extraordinary, they say, but when you consider the possibility it is a lizard, these anatomical features are much less remarkable. “You have to build the scientific story and significance carefully on a correct taxonomic identification,” the researchers told New Scientist. “We will be very excited to see what Oculudentavis khaungraae actually is, because this is still a very bizarre lizard and its position in the lizard family tree is uncertain.”

4-1-20 'Dinosaurs walked through Antarctic rainforests'
Scientists drilling off the coast of West Antarctica have found the fossil remains of forests that grew in the region 90 million years ago - in the time of the dinosaurs. Their analysis of the material indicates the continent back then would have been as warm as parts of Europe are today but that global sea levels would have been over 100m higher than at present. The research, led from the Alfred Wegener Institute (AWI) in Germany, is published in the journal Nature. It's emerged from an expedition in 2017 to recover marine sediments in Pine Island Bay. AWI and its partners, including the British Antarctic Survey (BAS), used a novel cassette drill-mechanism called MeBo to extract core material some 30m under the seafloor. When the team examined the sediments in the lab, it found traces of ancient soils and pollen and even tree roots. The interpretation is that this sector of West Antarctica, in the geological period known as the Cretaceous, featured temperate rainforest and swamp conditions - the kind of vegetation you will find on New Zealand's South Island today. "We have a really nice X-ray movie through the sediment core," said AWI's Prof Karsten Gohl, who spearheaded the expedition on Germany's Research Vessel Polarstern. "It's like we've drilled into a modern swamp environment and you're seeing the living root system, small plant particles and pollen - but this is all persevered from 90 million years ago. It's amazing." Modelling work suggests average annual temperatures in this Cretaceous environment would have been in the mid-teens Celsius; summer averages would have been in the 20s. But the vegetation must have been pretty special because, being so far south, it would have had to endure three to four months of polar darkness. The Nature paper's first author is AWI's Dr Johann Klages. "Probably these plants, they had a much more effective way of shutting down for a much longer amount of time and then come back successfully," he speculated. "That was quite an interesting adaptation, which is not present right now on the planet, but which can evolve," he told BBC News.

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