BOSTON, Mass. — Eating chocolate first thing in the morning probably sounds like an express ticket to obesity, but a new study finds it may be a healthier idea than many think. Researchers from the Brigham and Women’s Hospital say swapping out eggs and bacon for some chocolate can actually lead to burning more fat and lowering blood sugar levels throughout the day.

More specifically, an international team discovered that consuming chocolate during a narrow window of time after waking up improves health in a study of postmenopausal women. Researchers examined 19 women who ate 100 grams of chocolate within one hour of waking up each morning. The group also consumed the same amount of chocolate one hour before bed. The team then compared weight gain and other measures of health to people not eating chocolate.

Chocolate at breakfast won’t ruin your waistline

In news that will have chocolate fans jumping for joy, results show morning and nighttime chocolate eating did not lead to weight gain in these women. Moreover, eating chocolate at either time of day can influence a person’s appetite, gut microbiome balance, and sleep quality.

When it comes to breakfast, a bowl of chocolaty cereal appears to be a good way of getting your metabolism going. The study finds eating chocolate in the morning can increase fat burning ability. It also reduces blood glucose levels, a key measure for people at risk from diabetes. At night, eating chocolate before bed led to changes in the participants’ resting and exercise metabolism the following morning.

“Our findings highlight that not only ‘what’ but also ‘when’ we eat can impact physiological mechanisms involved in the regulation of body weight,” says study author and neuroscientist Frank A. J. L. Scheer in a media release.

“Our volunteers did not gain weight despite increasing caloric intake. Our results show that chocolate reduced ad libitum energy intake, consistent with the observed reduction in hunger, appetite and the desire for sweets shown in previous studies,” adds co-author Marta Garaulet, PhD.

The finding appear in The FASEB Journal.

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A new national study shows most patients in Australia are not getting suitable end-of-life care.

The paper, which looked at nine hospitals across Australia and tracked 1,693 dying patients, showed only 41 percent of dying patients will ever see a member of the palliative care team.

The findings show a majority of patients were recognized as dying only late in their hospital stay and only 12 percent had an advanced care plan, which outlines patients' wishes for when they die.

"At least 60 percent of people who die in Australia will die in a hospital setting and are at risk of not receiving appropriate end-of-life care," said lead author Professor Imogen Mitchell from The Australian National University.

Professor Mitchell, an Intensive Care Specialist who is based at Canberra Hospital, says patients should be given the chance to experience a more peaceful journey towards death.

"No one wants to think about dying, but we all need to because it will happen to all of us," she said.

"Frequently when I review imminently dying patients in the ward environment, it feels as if it is the first time they are being told they are dying.

"Decisions to involve palliative care or initiate a comfort care pathway is often left very late, often in the last 48 hours of life."

The researchers found a complex range of factors contribute to suboptimal end-of-life care, including failure to identify patients in their last months of life, substandard communication with patients and families, and failure to link medical teams.

"Patients experience inadequate palliative interventions such as delayed pain relief and we found inappropriate and futile investigations and treatments," Professor Mitchell said.

"Engaging the right end-of-life care allows for the best patient experience.

"No one would like to die in a busy and noisy emergency room with other patients when you could have had a much more peaceful dying journey if planned in advance."

The researchers say it can be challenging for hospitals to co-ordinate appropriate end-of-life care.

"A gold standard of end of life care is outlined in a consensus statement by the Australian Commission on Safety and Quality in Health Care and should be followed across the nation," Professor Mitchell said.

"By following these standards our dying patients and their families and carers will have a better experience."

The paper is published in Australian Health Review.

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Sydney was going through one the "scariest" times of the pandemic as a cluster of the highly contagious delta variant infects more people, an Australian state leader said on Thursday.

New South Wales Premier Gladys Berejiklian said she tested negative for the coronavirus after her Agriculture Minister Adam Marshall tested positive Thursday. Health Minister Brad Hazzard is self-isolating as a close contact of a suspected COVID-19 case in Parliament House.

Sydney tightened pandemic restrictions on Wednesday, but Berejiklian said Australia's largest city did not yet need to lock down further.

"Since the pandemic has started, this is perhaps the scariest period that New South Wales is going through," Berejiklian told reporters.

"It is a very contagious variant but at the same time we are at this stage comfortable that the settings that are in place are the appropriate settings," she added.

Authorities say the cluster spread from a Sydney airport limousine driver who tested positive last week. He was not vaccinated, reportedly did not wear a mask and is suspected to have been infected while transporting a foreign air crew. The cluster had grown to 36 cases by Thursday.

Police were considering charging the driver and his employer with a range of offenses, Police Force Deputy Commissioner Gary Worboys said.

Medical staff test people in their car at a COVID-19 testing station in Wellington, New Zealand, Thursday, June 24, 2021. After enjoying nearly four months without any community transmission of the coronavirus, New Zealanders were on edge Wednesday after health authorities said an infectious traveler from Australia had visited over the weekend. Credit: Mark Mitchell/NZ Herald via AP

Marshall tested positive after dining with three government colleagues on Monday at a Sydney restaurant after an infected diner.

All four lawmakers had been attending Parliament as recently as Tuesday.

Several government ministers, lawmakers and staff were told to get tested and isolate until July 6 after a positive case attended a political party dinner in Sydney on Tuesday. Australia's Deputy Prime Minister Barnaby Joyce also attended the dinner, but was allowed to attend Parliament in the national capital Canberra on Thursday after taking medical advice.

Australian states have closed their borders to travelers either from parts of Sydney or from anywhere in New South Wales. And New Zealand has stopped quarantine-free travel from New South Wales for at least three days.

Victoria state said it would continue to ease pandemic restrictions in its capital Melbourne following a fourth lockdown despite a Melbourne resident testing positive after returning from Sydney on Sunday.

People queue outside a COVID-19 testing station in Wellington, New Zealand, Thursday, June 24, 2021. After enjoying nearly four months without any community transmission of the coronavirus, New Zealanders were on edge Wednesday after health authorities said an infectious traveler from Australia had visited over the weekend. Credit: Mark Mitchell/NZ Herald via AP

Australia has been relatively successful in containing coronavirus clusters, although the delta variant first detected in India is proving more challenging.

The pandemic has claimed 910 deaths in Australia, which has a population of 26 million. The only COVID-19 death since October was an 80-year-old man who became infected overseas and was diagnosed in hotel quarantine.

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A typical Western high-fat diet can increase the risk of painful disorders common in people with conditions such as diabetes or obesity, according to a groundbreaking paper authored by a team led by The University of Texas Health Science Center at San Antonio, also referred to as UT Health San Antonio.

Moreover, changes in diet may significantly reduce or even reverse pain from conditions causing either inflammatory pain—such as arthritis, trauma or surgery—or neuropathic pain, such as diabetes. The novel finding could help treat chronic-pain patients by simply altering diet or developing drugs that block release of certain fatty acids in the body.

The paper, more than five years in the making, was published in the June edition of the journal Nature Metabolism by a collaborative team of 15 local researchers, headed by first co-authors Jacob T. Boyd, MD, Ph.D., and Peter M. LoCoco, Ph.D., of the Department of Endodontics at UT Health San Antonio.

In all, 11 of the co-authors are from UT Health San Antonio, including seven current or former students of its Graduate School of Biomedical Sciences; three represent the Department of Chemistry at the University of Texas at San Antonio; and one is from the Department of Neurology with the South Texas Veterans Health Care System.

"This study exemplifies team science at its best—multiple scientists and clinicians with complementary expertise working together to make lives better," said Kenneth M. Hargreaves, DDS, Ph.D., professor and chair of the Department of Endodontics at UT Health San Antonio, and senior author of the paper.

Fatty acids and pain

Chronic pain is a major cause of disability around the world. But although fat-reduction often is advised to manage diabetes, auto-immune disorders and cardiovascular diseases, the role of dietary lipids, or fatty acids, in pain conditions has been relatively unknown.

In the new paper, Dr. Boyd and his colleagues used multiple methods in both mice and humans to study the role of polyunsaturated fatty acids in pain conditions. They found that typical Western diets high in omega-6 polyunsaturated fats served as a significant risk factor for both inflammatory and neuropathic pain.

Omega-6 fats, mainly found in foods with vegetable oils, have their benefits. But Western diets associated with obesity are characterized by much-higher levels of those acids in foods from corn chips to onion rings, than healthy omega-3 fats, which are found in fish and sources like flaxseed and walnuts.

Generally, unhealthy foods high in omega-6 fats include processed snacks, fast foods, cakes, and fatty and cured meats, among others.

Reversal of this diet, especially by lowering omega-6 and increasing omega-3 lipids, greatly reduced these pain conditions, the researchers found. Also, the authors demonstrated that skin levels of omega-6 lipids in patients with Type 2 diabetic neuropathic pain were strongly associated with reported pain levels and the need for taking analgesic drugs.

"This paper is a high-profile contribution for a huge unmet translational need as there are no treatments altering the nature of this neurological disease," said José E. Cavazos, MD, Ph.D., professor of neurology, assistant dean and director of the National Institutes of Health-designated South Texas Medical Scientist Training Program at UT Health San Antonio.

In an editorial accompanying the paper, Duke University researchers Aidan McGinnis and Ru-Rong Ji wrote, "This comprehensive and elegant study from Boyd et al. may serve as a foundation for new clinical trials and ultimately provide new avenues for the clinical treatment of neuropathies."

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Many a pub crawler has engaged in the time-honored tradition of throwing beer mats—those round cardboard coasters that are ubiquitous in bars—as if the mats were frisbees, often competing to see who can throw one the farthest. But unlike frisbees, beer mats tend to flip in the air and fly with a backspin. Now physicists at the University of Bonn have come up with a theoretical model to explain the phenomenon, according to a new paper submitted to the physics arXiv preprint server.

 

Thanks to their natural curiosity, physicists are fascinated by the physics of beer, and lead author Johann Ostmeyer is no exception. A couple of years ago, he became intrigued by the physics of so-called "beer tapping": a common prank where the perpetrator, holding an open bottle of beer, finds a target in the bar holding another open bottle. The prankster strikes the top of the target's bottle with the bottom of their own, then savors the sight of beer explosively foaming all over the target's hands and clothes.

 

Back in 2013, Javier Rodríguez-Rodríguez, a physicist at Carlos III University of Madrid, and several colleagues presented experimental and computer-simulation findings of why beer cans foam up so much after being shaken. They concluded that the foaming-over stemmed from a series of waves. Apparently the physics is similar to the development of the cloud in an atomic bomb, although the source of the "explosion" is very different.

The initial tap creates a shockwave that travels from the top to the bottom of the target's bottle. That shockwave's energy is transferred to the beer, sending a second shockwave bouncing back and forth between the bottom of the bottle and the beer's surface. All that activity releases tiny pockets of gas trapped in small imperfections in the bottle's glass, creating clouds of smaller bubbles from the beer's dissolved CO2. As they rise to the surface, those bubbles get bigger and speed up, eventually creating the shower of foam that makes beer tapping such a popular pub prank.

 

Ostmeyer submitted his own analysis on the beer tapping issue to the arXiv last year, specifically focusing on why the lower beer bottle foams over and the upper one does not. The initial tap creates a low pressure in the lower bottle, and the CO2 bubbles expand and collapse into fragments.

 

More gas gets diffused into the cluster of bubbles, rising up to create the foam. Something different happens in the top bottle. There is a higher initial pressure, so there are only moderate oscillations in the bubbles, and the eventual bubble collapse doesn't happen—or at least not to the same extent. Thus, you don't get the same rapid growth cloud turning your entire beer into foam. "The prankster leaves the scene dry," Ostmeyer wrote.

 

Now Ostmeyer, inspired by a 2017 trip to Munich for a German physics outreach demonstration show, has turned his attention to the pressing question of beer-mat flight trajectories. Beer mats (at least the round variety) are basically thin, flat disks with a given radius and mass. A frisbee is also a thin flat disk, and the physics surrounding its flight is well-known.

 

A frisbee's distinctive curved upper surface is essentially the same shape (when viewed from the side) as an airfoil. Throw it with sufficient force to overcome the downward pull of gravity, and it will generate lift. Of course, there is also air resistance, or drag, acting on the frisbee as it flies through the air. The resistance depends on the angle of attack. If the angle is negative, it pushes the air up and forces the frisbee down, while a positive angle will push the frisbee up. To keep wobbling to a minimum, professional frisbee players know to add a spin when they throw, ensuring their frisbees stay on a single plane as they travel.

 

A dog's delight: the frisbee's long, stable flight trajectory is due to its airfoil-like shape.

First image of article image gallery. Please visit the source link to see all images.

But beer mats don't have the frisbee's distinctive airfoil-like edge, and that affects their aerodynamics. Ostmeyer et al. began by assuming a horizontal flight and an axis of rotation perpendicular to the direction it is moving. Toss a beer mat like a frisbee, and the rotation will initially stabilize it.

However, the pull of gravity will soon cause the mat to drop, which will alter the angle at which it attacks the air. You'll still get lift, but it will be focused close to the leading edge rather than the mat's center of mass. So the mat will start to precess, forcing it to flip on its side so that it is traveling vertically. The researchers' model predicted that this should happen at about 0.45 seconds into the flight. Furthermore, the model showed that the mat could have either a backspin (which is stable) or a topspin (which is unstable). Thus, the mat will be more likely to have a backspin.

Every good theoretical prediction must be experimentally tested, of course, and randomly tossing beer mats around in the local pub wouldn't be scientifically rigorous. Thrown by hand, the timing of the tilt appears to be random, but the model predicts otherwise. So Ostmeyer and his team built their own makeshift beer-mat launcher out of two electric motor-powered treadmills. The launcher enabled the researchers to control the horizontal velocity and rate of rotation of each launch.

The researchers placed the launcher on a table, then placed a beer mat between the treadmills and launched the mats at various speeds, marking where they landed on the floor. The flight trajectories were recorded with high-speed cameras, and the team used a program called Tracker to extract the coordinates of the beer mat at any point along its trajectory. The results of the researchers' subsequent analysis showed very good agreement with the theoretical predictions.

Ostmeyer et al.'s theoretical model can also be used to predict the flight trajectories of other kinds of flying discs. For instance, their model predicts that a CD will flip after 0.8 seconds, while a larger and heavier discus will flip after 16 seconds. A flying playing card has the shortest trajectory of all, flipping after just 0.24 seconds. "Even Rick Smith Jr., the world record holder for farthest card thrown, or a playing card machine gun, cannot avoid their cards flying a curve and ending up with backspin after much less than a second," the authors wrote in a footnote.

The model's prediction for a frisbee—without taking into account any aerodynamics due to its curvature—is a surprising 0.8 seconds. "Of course, the wing form of a frisbee allows it to remain stable for a much longer time when thrown professionally," they wrote. "The reason is that frisbees have their aerodynamic center very near to their center of mass and, thus, experience much less torque."

We raise a glass to Ostmeyer and his colleagues for their entertaining and informative work, which was driven purely by scientific curiosity."Our sincere apologies to everyone hit by a beer mat," the authors noted in their acknowledgements, "be it through inaccurate aim or due to us instigating others to perform silly experiments."

Physicists show that flying beer coasters will flip 0.45 seconds into flight

(To view the article's image gallery, please visit the above link)

The Coelacanth May Live for a Century. That’s Not Great News

Scale markings reveal that this weird fish's lifespan is double what scientists first estimated. That also means they’re closer to extinction than we thought.

 

African coelacanths are very old. Fossil evidence dates their genesis to around 400 million years ago, and scientists thought they were extinct until 1938, when museum curator Marjorie Courtenay-Latimer noticed a live one in a fisher’s net.

 

Found off the southeastern coast of Africa, coelacanths also live a long time—scientists have suspected about 50 years. But proving that lifespan has been tough. (Coelacanths are endangered and accustomed to deep waters, so scientists can’t just stick their babies in a tank and start a timer.) Now a French research team examining their scales with polarized light has determined that they can likely live much, much longer. “We were taken aback,” says Bruno Ernande, a marine ecologist who led the study. The new estimated lifespan, he says, “was almost a century.”

 

His team from the French Institute for the Exploitation of the Sea, or IFREMER, found not only that individuals can live to nearly 100 but also that they have gestation periods of at least five years, and may not mature sexually until they’re at least 40. The results were published on Thursday in Current Biology. This slow-motion life highlights the importance of conservation efforts for this rare species, which is marked as “critically endangered” on the IUCN Red List. Only about 1,000 exist in the wild, and their long gestation and late maturity are bad news for their population’s resilience to run-ins with humans. “It's even more endangered than we previously thought,” Ernande says.

 

“It will have enormous consequences,” agrees Daniel Pauly, an ichthyologist from the University of British Columbia, who was not involved in the study. Pauly is the creator of FishBase, a database of biological and ecological information about tens of thousands of species. If a fish takes decades to spawn, then killing it wipes out its potential to replenish the population. “A fish that needs 50 years to reach maturity, as opposed to 10 years, is five times more likely to be in trouble,” he says.

 

Coelacanths have thick scales that grow up to two inches long, and for decades ichthyologists have been debating how to read those scales for signs of age. In the 1970s, researchers noticed small calcified structures on them. They figured the rings were age markers, like tree rings. They disagreed, however, on how to count them: Some figured that each marking denoted one year; others believed that seasonal flips created two rings per year. At the time, the best guess placed their life expectancy at about 22 years. That conclusion, which meant that a 6-foot, 200-pound coelacanth is 17 years old, implied that they grow very quickly: “They would grow as fast as tuna, which is crazy,” Pauly says.

 

It’s crazy because these are animals with slow metabolisms, which should indicate slow growth. Coelacanths’ hemoglobin is adapted to that slow metabolism, which means they can’t take in enough oxygen to support a fast-growing fish. Some argue that their small gills are further evidence of oxygen limitations. They also live very passive lifestyles, resting most of the day in caves and lumbering slowly through the ocean’s twilight zone, down at 650 feet and below, when they do deign to move around. “Overwhelmingly, the biological features were pointing to a slow-living fish,” says Ernande.

 

Plus, scientists tracking the lives of individual coelacanths have known that 20 years is far too low. In the 1980s, researchers started sending submersibles and remote-operated vehicles down to a cave harboring 300 to 400 coelacanths. They returned to this spot for over 20 years. During each visit, they recognized individuals by their characteristic white markings. Only about three or four fish in this group would die, and an equal number of new ones would be born, each year. This observation provided striking evidence that coelacanths live long lives—even more than 100 years, that study argues.

 

But a population assessment doesn’t pin down age or lifespan directly. Intrigued by this gap, Ernande and his colleagues began tackling coelacanth age as a “fun side project.” He and the study’s lead author, Kélig Mahé, had been determining the ages of species that are commercially fished. Knowing the relationship between a fish’s age and its size helps forecast—and conserve—future populations. They figured they’d conduct a similar analysis for the coelacanth, but since they are endangered, they couldn't fish for them or find any in an aquarium. They instead requested museum specimens from France and Germany.

The usual way of determining a fish's age is by looking at its otoliths, inner-ear stones that fish use for hearing; they also record the passing years as the calcium carbonate builds up. But otoliths are inside fish heads. Would the French National Museum of Natural History let researchers chop open their prized collection to dig out the little stone for a "fun side project"? The team didn’t even bother asking.

 

Instead they focused on examining the fish’s scales. In previous studies devoted to counting their rings, researchers had examined them by microscope under regular light. Mahé had something else in mind: polarized light. Light waves normally vibrate every which way, not just the direction in which the wave is traveling. Polarized light is like streaking a comb through messy hair—all the waves now vibrate in the same plane. (The glare of sunlight bouncing off a river is polarized; that’s why polarized sunglasses can filter that entire bundle of rays out simultaneously.) When light hits a sample containing minerals—as calcified fish scale structures do—the polarized light exaggerates these minerals against the rest of the scale, making otherwise invisible structures visible.

 

The polarized light microscope revealed five times more rings in the coelacanth’s scales than anyone had seen before. These “circuli” were much more fine than the larger and sparse “macrocirculi” that had been observed in the ’70s, and they appeared across all of the museum’s 27 specimens, which ranged from embryos to nearly full-grown adults. Counting circuli told a completely new story: Coelacanths grow very slowly, and they can live extremely long. A coelacanth thought to be 17 years old, if you only counted its macrocirculi, would instead be about 85.

 

To validate the new approach, the team charted the relationship between each fish’s size and age. Like other fish, coelacanths should grow logarithmically—at first a period of fast growth, followed by a slow plateau as they approach a maximum lifespan. The new ages made sense. Smaller specimens fit neatly in the range they would expect of a fast-growing adolescent, and the largest specimens fit in a slower-growth phase that plateaued near 2 meters and around 100 years old.

 

The rings found on two large embryos also suggested that they gestate for at least five years. “As far as we know, this is the longest gestation period for a fish,” Ernande says.

Coelacanths become reproductively mature when they’re about 5 feet long. And based on the growth model for the species, Ernande’s team concluded, coelacanths don’t reach that length until they are 40 to 69 years old. That time until sexual maturity is among the longest of any known species.

 

“That is crazy old,” says Prosanta Chakrabarty, an ichthyologist from Louisiana State University who is not involved in the study. “So old that it makes me kind of dubious, to be honest.” He completely buys the team’s lifespan conclusion. But, he says, the deduction that coelacanths can’t reproduce until halfway to two-thirds of the way into it is extraordinary. And extraordinary claims need extraordinary evidence.

 

The age range for spawning may be off, since it’s deduced from previously reported sizes of mature individuals and their model for determining age from size. To him, the team could solidify the sexual maturity conclusion by accessing one or two coelacanth otoliths or repeating the same scale analysis in other species of fish. “It just comes down to scales,” Chakrabarty says. “Show me that the scales on a brown ruffe, which can also live 100 years, would work in the same way.” Lungfish, a fellow long-lived and limb-finned fish like the coelacanth, could also provide extra assurance in the method, he says.

 

Ernande shares Chakrabarty’s caution. But since ichthyologists are fairly confident that coelacanths don’t mature while smaller, and coelacanths clearly grow slowly, Ernande is satisfied with his team’s conclusion. “Even though it might not be 50, but 40, or 35, it's still a very old age. That's for sure,” he says.

Pauly is not surprised that coelacanths take so long to mature: “Fish don't know their age, they know their size.” When a fish gets bigger, it has more trouble breathing. Their body grows in volume, but the gills only grow in surface area. So as the surface-to-volume ratio decreases. At about one third of their maximum weight, a transition to sexual maturity begins. “This tension between the gills and the body—between the oxygen supply and the oxygen need—triggers a transition to do spawning,” Pauly says.

 

The coelacanth’s delayed sexual maturity and long gestation suggests that conservation efforts are extra important, because any animal that’s lost cannot be quickly replaced. If it takes 40 years for an individual to mature and five more to gestate, removing any adult would make the population “quickly collapse,” Pauly says.

 

Their unique look and reputation for long life has made coelacanths vulnerable to illegal trafficking and incidental catches in Madagascar. People in the neighboring Comoros Islands sometimes fish them as well. “They were using the scales like sandpaper for their bicycles,” according to Pauly.

 

Ernande’s team has turned their side project into a major focus area—they now plan to expand their analysis with more and larger specimens. (Perhaps a larger coelacanth might even be older than 100.) And a new area of focus for them will be measuring the fish’s climate resilience. If coelacanths struggle to extract oxygen from warmer water, evidence could show up in their scale rings. If warm water years show up as tighter rings, that’d mean they are growing slower and maturing later as the planet warms—more bad news for coelacanths.

 

His team won’t know until they glean more stories from the coelacanths’ anatomy. They hope these life stories and climate stories told on a yearly timescale, printed finely on scales of a different sort, will not be cut short.

The Coelacanth May Live for a Century. That’s Not Great News (May require free registration to view)

Who could know we’re here on Earth?

A survey of nearby bodies reveals a lot of stars from which Earth is detectable.

The search for extraterrestrial intelligence (SETI) has primarily involved looking outward and searching nearby stars for signals that can't be explained by known natural processes. But there has also been consideration given to the possibility that an extraterrestrial intelligence might be looking for us. Investigations have included intentional signals sent to nearby stars and calculations of how far out our civilization's radio transmissions will reach.

 

A new study focuses on the question of who might be capable of detecting us and considers how we're looking for signs of life around other stars. The study estimates that the Earth is surrounded by thousands of star systems from which hypothetical inhabitants would be able to detect our presence via the same techniques we've been using to search for life around other stars. And civilizations orbiting a significant number of those stars would also be able to detect things like oxygen in our atmosphere or the radio signals we have produced over the last century or so.

A shifting landscape

The new analysis, done by researchers Lisa Kaltenegger and Jacqueline Faherty, relied on data from the European Space Agency's Gaia mission, which was put in space to generate a three-dimensional map of the Milky Way. But the Milky Way isn't static; its stars rotate in synchrony, but they also move relative to each other. For many stars, repeated observations by Gaia also allowed an estimation of their motion relative to the Sun. This allowed Kaltenegger and Faherty to extend their analysis forward and backward in time, creating a window 10,000 years wide and centered on the present.

 

The size of this window is important because the stars closest to the Sun will tend to have the largest relative motion. Therefore, the orientation of their view toward the Sun will change more rapidly than that of distant stars.

 

Our most successful method of finding exoplanets has involved looking for transits—periods when a planet's orbit takes it between its host star and the Earth, allowing it to block some of the star's light. Because we know the orientation of the Earth's orbit relative to the rest of the Milky Way, it's possible to figure out what stars are in a position to observe our transits. And because we can run the clock forward and backward in time, we can identify which stars have been in a position to detect us in the past or will move into a position to do so in the future.

 

In most cases, we don't know whether planets orbit these stars, and there's no indication of life out there. This is simply a calculation of positions from which observing Earth would have been possible.

My god, it’s full of stars

Kaltenegger and Faherty limited their analysis to the nearest 325 light-years—that's 100 parsecs for those confused by the random-looking number. But even that figure is a bit arbitrary. We've identified exoplanets much farther out than that, while we'll only be able to study the atmospheres of rocky planets within 30 light years or so for the next few decades. The authors also looked within a 100-light-year radius because that's the rough distance our radio transmissions will have reached.

 

As it turns out, plenty of stars could have spotted Earth. The two authors count over 2,000 of them, with the vast majority being able to detect Earth's transits at present. (Three hundred and thirteen have lost the ability to image Earth, but another 319 will move into position over the next 5,000 years.) For about two-thirds of these stars, Earth's transits would last for at least 10 hours, making them relatively easy to spot; 868 of them will spend over 10,000 years in locations where the transits would be visible. So overall, there are a lot of opportunities to see Earth among this population.

 

Are any of these systems likely to host life? There are two bits of relevant data. One is the star type, which is mostly favorable. Roughly 200 of the stars are Sun-like, and over 1,000 are M dwarfs, a smaller, redder star that is the most common type in the galaxy. The rest are a mix of smaller and larger stars, including 75 white dwarfs.

 

The other relevant data point is the presence of planets. Based on estimates of the frequency of rocky planets found in the habitable zone of their stars, Kaltenegger and Faherty estimate that there would be over 500 planets with the potential to be Earth-like. Seven stars within the 325-light-year radius have confirmed planets. But the list includes TRAPPIST-1, which has seven known planets; one other has at least two. So this list of seven stars represents significantly more planets (although TRAPPIST-1 won't be in a position where the Earth could be detected for another 1,600 years or so.)

 

The other radius that Kaltenegger and Faherty looked at was 100 light-years, the area that our radio transmissions would have reached since the invention of the medium about a century ago. There are 117 objects in that region, 46 of which have had extensive observational time within the past 100 years. The number includes four of the stars known to host planets; based on the frequency of rocky planets, 29 of them could be within this region.

Signs of life?

Five thousand years ago isn't an especially relevant interval, as it's well after the origin of agriculture and the formation of the first cities (although only the former might be detected from a distance). Perhaps more relevant is the origin of the steam engine and the large surge in carbon emissions that it eventually produced. The elevated carbon dioxide might be detectable from space, although natural events can also cause a surge in carbon dioxide levels. Really, the most compelling indication of life here that could be detected from a distant star is likely to be the simultaneous presence of oxygen and methane in the atmosphere at the same time. And that, as Kaltenegger and Faherty note, would take us back to the oxygenation of the Earth's atmosphere, about a billion years ago.

 

So any life on a nearby planet is likely to have had a substantial amount of time when it might have been able to detect Earth and study our atmosphere—assuming those aliens used methods similar to the ones we developed, at least. But it's also worth noting that life on Earth needed well over 3 billion years to develop those methods, and it remains unclear how long we'll be able to maintain them.

 

Nature, 2021. DOI: 10.1038/s41586-021-03596-y  (About DOIs).

Who could know we’re here on Earth?

24,000 years on ice weren’t enough to kill these guys

Ancient species may re-enter the ecosystem as the world's permafrost thaws.

 

Rotifers are microscopic freshwater-dwelling multicellular organisms. They're already known to withstand freezing (even in liquid nitrogen), boiling, desiccation, and radiation, and the group has persisted for millions of years without having sex. The humble yet remarkably hardy bdelloid rotifer has now surprised researchers yet again—a recent study unearthed 24,000-year-old Siberian permafrost and found living (or at least revivable) rotifers there. Surviving 24,000 years in deep-freeze is a new record for the species.

 

Rotifers aren’t the only living organisms to emerge from permafrost or ice. The same researchers behind this latest discovery had previously found roughly 40,000-year-old viable roundworms in the region’s permafrost. Ancient moss, seeds, viruses, and bacteria have all shown impressive longevity on ice, prompting legitimate concern about whether any potentially harmful pathogens may also be released as glaciers and permafrost melt.

 

Given that bdelloids are generally only a threat to bacteria, algae, and detritus, however, there’s not much need for concern regarding this particular discovery. But as key players in the bottom of the food chain, newly re-emerged rotifers indicate that maybe we should think about how species that haven’t been seen for millennia might reintegrate into modern ecosystems.

Frozen zoo

The Soil Cryology Lab in Pushchino, Russia, has been digging up Siberian permafrost in search of ancient organisms for roughly a decade. The group estimates the age of the organisms it finds by radiocarbon dating the surrounding soil samples (evidence has shown that there is no vertical movement through layers of permafrost). For example, last year, the researchers reported a “frozen zoo” of 35 viable protists (nucleus-containing organisms that are neither animal, plant, nor fungus) that they calculated ranged from hundreds to tens of thousands of years old.

 

In their most recent discovery, the cryology researchers found the living bdelloids after culturing the soil samples for about one month. Among rotifer classes, bdelloids have the fairly unusual ability to reproduce parthenogenetically—i.e., by cloning—and so the original specimens had already begun to do so. Although the clones made identifying the ancient parent challenging, this did greatly facilitate further investigation of the characteristics and behavior of the unfrozen strain.

 

Throughout all of the above permafrost studies, there is always the concern of sample contamination by modern-day organisms. Besides using techniques designed to prevent this, the team also addressed this issue by looking at the DNA present in the soil samples, confirming that contamination was highly unlikely. Phylogenetic analysis furthermore showed that the species didn’t match any known modern rotifers, although there is a closely related species found in Belgium.

Thaw, clone, freeze, repeat

The team was naturally interested in better understanding the freezing process and gaining insight into just how these rotifers survived for so long. As a first step, the researchers subsequently froze a selection of the cloned rotifers at -15° C for one week and captured videos (see above) of the rotifers reviving.

 

The researchers found that not all of the clones survived. Surprisingly, the clones generally weren’t much more freeze-tolerant than contemporary rotifers from Iceland, Alaska, Europe, North America, and even the Asian and African tropics. They were a little more freeze-tolerant than their closest genetic relative, but the difference was marginal.

 

The researchers did find that the rotifers could survive a relatively slow freezing process (~45 minutes). This is noteworthy because it was gradual enough that ice crystals formed inside of the animals’ cells—a development that is usually catastrophic for living organisms. In fact, protective mechanisms against this are highly sought-after by anyone in the business of cryo-preservation, making this latest finding especially enticing from that perspective.

 

Although the authors aren’t quite in that business, they do plan additional experiments to better understand cryptobiosis—the state of almost completely arrested metabolism that made the rotifers’ survival possible. As for research into cryo-preservation of larger organisms, the authors suggest that this becomes trickier as the organism in question becomes more complex. That said, rotifers are among the most complicated cryo-preserved species so far—complete with organs such as a brain and a gut.

 

Which returns us to the questions of what other organisms might reappear with a warming climate and what impacts they might have. Evidence so far shows that multiple types of organisms are still alive in the ice. At least on a microscopic level, it seems possible that intact micro-ecosystems may thaw together (nematodes, rotifers, protists, viruses, bacteria, etc.). How these long-dormant species will compete or coexist with modern ecosystems is difficult to predict at this point, but it’s probably worth further consideration.

 

Current Biology, 2021. DOI: 10.1016/j.cub.2021.04.077  (About DOIs).

 

K.E.D. Coan is a freelance journalist covering climate and environment stories at Ars Technica. She has a PhD in chemistry and chemical biology.

24,000 years on ice weren’t enough to kill these guys

Throughout her 20-year career as a nurse practitioner, Jennifer Hulett noticed survivors of breast cancer would often express gratitude for being alive and mention God or a divine acknowledgement that had improved their health and well-being.

Now an assistant professor at the University of Missouri Sinclair School of Nursing, Hulett is researching the benefits of spirituality on improving immune health and reducing stress, as well as the chances of cancer reoccurrence, among breast cancer survivors.

In a recent study, Hulett collected and froze samples of saliva from 41 breast cancer survivors at MU's Ellis Fischel Cancer Center. She identified breast cancer survivors' reports of practicing forgiveness and receiving positive social support from their congregation or other social support network were linked with two specific biomarkers, alpha-amylase and interleukin-6. The findings lay the foundation for further examining the role spirituality plays in the health and well-being of both cancer survivors and individuals managing chronic disease.

"Breast cancer survivors are often a highly spiritual group given the trauma they have been through, and we found they often have more positive spiritual beliefs in a loving God or higher power rather than a punitive, punishing God," Hulett said.

"This confirmed what I had previously experienced anecdotally as a nurse. Breast cancer survivors would often express gratitude and contribute their health and well-being to a higher power, and they tended to have better health outcomes as well."

Hulett's research builds off previous findings indicating positive spiritual beliefs are associated with healthier levels of cortisol, a biomarker commonly associated with stress, among breast cancer survivors.

"Cortisol and stress suggest chronic inflammation, and anything we can do to lower levels of stress and inflammation will have a good effect on a patient's longevity, health outcomes and reduced risk of reoccurring disease," Hulett said. "We often hear about diet and exercise in promoting physical health, but we rarely hear about the importance of managing stress, and all three are connected with well-being."

One in eight women develop breast cancer at some point in their lives, and previous studies show chronic stress in breast cancer survivors is linked with increased inflammation and risk for cancer reoccurrence.

"We know cortisol is linked with stress, and elevated levels of the immune biomarker interleukin 6 suggests inflammation," Hulett said. "By first finding out which biomarkers are meaningful to look at, we can then see how they are potentially influenced by various spiritual or mindfulness practices aimed at reducing inflammation."

Hulett's research sets the foundation for future research that evaluates the effectiveness of spiritual and mindfulness interventions, including daily prayer, mediation, yoga and relaxation, on health outcomes among cancer survivors and individuals with chronic disease.

"We already know these interventions improve mental health, but they might also improve physical health as well, and we can try to prove it by looking at these physiological biomarkers," Hulett said. "These spiritual interventions are what nurses can use at the bedside to quickly implement if they see patients struggling to cope with their illness. Any evidence-based solutions we can equip nurses with will help improve patient health outcomes, and that is where these mind-body interventions can play a role going forward."

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A year-long Australian population study has found that full time workers employed by organizations that fail to prioritize their employees' mental health have a threefold increased risk of being diagnosed with depression.

And while working long hours is a risk factor for dying from cardiovascular disease or having a stroke, poor management practices pose a greater risk for depression, the researchers found.

The University of South Australia study, published in the British Medical Journal today, is led by UniSA's Psychosocial Safety Climate Observatory, the world's first research platform exploring workplace psychological health and safety.

Psychosocial safety climate (PSC) is the term used to describe management practices and communication and participation systems that protect workers' mental health and safety.

Lead author, Dr. Amy Zadow, says that poor workplace mental health can be traced back to poor management practices, priorities and values, which then flows through to high job demands and low resources.

"Evidence shows that companies who fail to reward or acknowledge their employees for hard work, impose unreasonable demands on workers, and do not give them autonomy, are placing their staff at a much greater risk of depression," says Dr. Zadow.

Internationally renowned expert on workplace mental health, ARC Laureate Professor Maureen Dollard, says the study found that while enthusiastic and committed workers are valued, working long hours can lead to depression. Men are also more likely to become depressed if their workplace pays scant attention to their psychological health.

Due to the global burden of depression, which affects an estimated 300 million people worldwide and shows no sign of abating despite available treatments, more attention is now being paid to poorly functioning work environments which could contribute to the problem.

High levels of burnout and workplace bullying are also linked to corporations' failure to support workers' mental health.

A second paper co-authored by Professor Dollard and published in the European Journal of Work and Organizational Psychology earlier this month, found that low PSC was an important predictor of bullying and emotional exhaustion.

"Lack of consultation with employees and unions over workplace health and safety issues, and little support for stress prevention, is linked to low PSC in companies."

"We also found that bullying in a work unit can not only negatively affect the victim, but also the perpetrator and team members who witness that behavior. It is not uncommon for everyone in the same unit to experience burnout as a result."

"In this study we investigated bullying in a group context and why it occurs. Sometimes stress is a trigger for bullying and in the worst cases it can set an 'acceptable' level of behavior for other members of the team. But above all bullying can be predicted from a company's commitment to mental health, so it can be prevented," Prof Dollard says.

The global costs of workplace bullying and worker burnout are significant, manifested in absenteeism, poor work engagement, stress leave and low productivity.

The extent of the problem was recognized in 2019 with the International Labour Organization (ILO) implementing a Global Commission on the Future of Work and calling for "a human-centered approach, putting people and the work they do at the center of economic and social policy and business practice".

"The practical implications of this research are far reaching. High levels of worker burnout are extremely costly to organizations and it's clear that top-level organizational change is needed to address the issue," Prof Dollard says.

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PICO RIVERA, Calif. (AP) — Forty cows escaped a slaughterhouse and ended up in a Los Angeles suburb where one was killed after charging a family, authorities said Wednesday.

The cows were reported running loose on the streets of Pico Rivera around 7:30 p.m. Tuesday after a gate at a meat packing facility was accidentally left open, the Los Angeles County Sheriff’s Department said in a statement.

The herd made its way to a neighborhood about a mile (1.6 kilometers) away and one cow charged at four members of a family, knocking them to the ground. They suffered minor injuries.

A sheriff’s deputy shot and killed the cow to protect the family from further injury, the sheriff’s department said. The family members were taken to a hospital for treatment.

Pico Rivera City Manager Steve Carmona told KTLA-TV that at one point he had to jump onto a car to get out of the way of the herd.

“It was a pretty scary ordeal,” he said.

The sheriff’s unit that rides horses was dispatched to help recapture and transport the cows.

“Of the forty, thirty-eight were safely captured, one was shot, and one has not been located,” the department said.

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The pandemic and climate change is testing as never before the delicate balance of human co-habitation with the natural world.

As an Australian prison is evacuated after it was overrun by the plague of mice ravaging the east of the country, we look at some of the most spectacular recent examples.

- Australia mice plague -

Battling a massive plague of mice after the end of a three-year drought, eastern Australia is seeing crops destroyed, grain silos and barns infested and homes invaded by the rodent that was first introduced to the country by European colonialists.

Skin-crawling videos of writhing rodent masses have been shared around the world along with reports of patients bitten in hospital, destroyed machinery and swarms running across roads en masse.

In the latest twist on Tuesday, mice forced the evacuation of hundreds of inmates from a jail after they gnawed through ceiling panels and wiring.

Experts warn that climate change could make such chronic infestations more regular.

Indeed the Gippsland region in the southeast of the country has been covered in a sea of spider webs after an invasion of sheet web spiders fleeing flooding in early June.

- China's herd -

A herd of elephants which has wandered off its reserve in Yunnan province in China has made headlines around the world, with 3,500 people in their path evacuated from their homes and hundreds of trucks deployed to keep them away from densely populated areas.

State broadcaster CCTV is carrying a 24-hour live feed of the migration which began late last year and which has so far cost farmers more than a million dollars in damage to crops.

- Elephant in the room -

An elephant stuck his head through Kittichai Boodchan's kitchen wall in western Thailand on Sunday night to nose through his larder for a midnight snack.

Kittichai lives near a national park and this was not the first such visit. Last month the elephant knocked a hole through the wall, creating an opening reminiscent of a drive-through restaurant window.

- Tough teen -

A California teenager became a social media sensation when a video of her shoving a large bear off her suburban garden wall to protect her dogs went viral earlier this month.

"The first thing I think to do is push the bear. And somehow it worked," said the 17-year-old, whose shove sent the bear falling off the low wall and retreating with her cubs.

- Conservation controversy -

But there was a grim end to another ursine encounter in Slovakia last week when a brown bear killed a 57-year old man outside Bratislava.

The death sparked fury from hunters who claim that bear numbers have become too high because of a ban on hunting to save the species.

The outcry echos similar debates in other countries over bear conservation.

- Wolves divide -

The protection of wolves is equally divisive, with an outcry in the US in March after licensed hunters in Wisconsin killed 216 wolves in 60 hours -- a fifth of the state's entire population.

Donald Trump lifted federal protection for wolves, exposing them to trophy hunting in several states.

A similarly heated debate is raging in France where the wolves have flourished since 1992, after being previously hunted to extinction.

While their numbers are only a fraction of those found in Italy, Spain, Romania or Poland, farmers baulk at the ban on killing the predator across most of the EU.

- Gatecrashing boars -

Wild boars also raise hackles across most of continental Europe, damaging well-manicured lawns and golf courses from the French Riviera to the Baltic, where they have become notorious for venturing into residential areas looking for food.

In one of the funnier incidents, a German wild boar stole a nudist's laptop last year by a lake in Berlin, with a video of the naked sunbather chasing after the animal clocking up millions of views.

- Lockdown liberty -

Pandemic lockdowns have brought a new-found freedom to many wild animals, allowing them to wander into the heart of cities.

With half the world's population locked down last year, social media was full of images of wildlife reclaiming the streets, from herds of wild sika deer wandering through metro stations in Japan to packs of jackals congregating in the centre of Tel Aviv in Israel.

Source

Australia's current crop of COVID-19 vaccines consists of a shot by American biotechnology company Pfizer, which we import, and the vaccine by British-Swedish multinational AstraZeneca, the bulk of which we manufacture onshore in Melbourne under license.

We don't currently have a locally-made COVID vaccine at our disposal, though this week the Victorian government announced funding for a Pfizer-style mRNA vaccine developed by Monash University. It will move to phase 1 trials in October or November.

However, the most advanced of our local COVID vaccines in development is a shot called "COVAX-19" by South Australian based biotech, Vaxine.

It's great to see another Australian group at the forefront of COVID-19 research and particularly vaccine development.

The candidate has just started a phase 2 clinical trial in Iran, collaborating with local biotech CinnaGen.

We're yet to see the published results of the pre-clinical animal studies or the phase 1 human trials, though Vaxine says it has submitted research papers and is awaiting acceptance.

At this point in time, there's unfortunately not enough information to comment on the safety and efficacy of this locally developed vaccine, though it's potentially promising.

Further information, particularly the results of the clinical trials, is eagerly awaited.

What is Vaxine?

Vaxine was founded in 2002 with the aim of developing new vaccine technologies.

Researchers at Vaxine have focused for some time on adjuvants, which are substances added to vaccines to enhance the response of the immune system. They've developed their own adjuvant named "Advax" which is based on Inulin, a starchy product derived from many plants.

This adjuvant has been used safely and successfully in human trials for many viruses including influenza and hepatitis B. However, it hasn't been included in any licensed vaccine to date.

What kind of vaccine is it?

Vaxine scientists began work on a COVID-19 vaccine in January 2020. They describe developing a number of different types of vaccines, but eventually settled on a "recombinant protein-based vaccine."

The goal of any vaccine is to train our immune system to recognize something found on the surface of a pathogen, in this case the SARS-CoV-2 coronavirus. Having a vaccine means if we encounter that virus, we'll have antibodies and other immune cells ready to protect us.

In the case of COVID-19, most of the vaccines in use and under development target the spike protein, as this is the part of the virus that binds to human cells to get in and cause infection.

Vaxine's COVAX-19 is no exception and does this by making the spike protein in the laboratory using "recombinant technology," which is where proteins are artificially manufactured.

Other similar vaccines include those made by Novavax and the University of Queensland.

Novavax's candidate uses their own adjuvant and this month announced impressive results from phase 3 studies.

The University of Queensland candidate used a "molecular clamp" which, unfortunately, caused some participants who received the vaccine in trials to have false-positive HIV tests. Because of this, the vaccine isn't going to progress beyond phase 1 clinical trials.

Is it safe and effective?

Vaxine's website states its COVAX-19 vaccine has been shown to produce an immune response in a number of animals including mice, macaques and ferrets. The data is not published, so I can't confirm this.

For results to be published, it means they have been carefully analyzed and presented as well as undergoing a robust peer review process. While results from press releases and pre-print articles can tell us exciting results might have been obtained, we really need to see them published in reputable peer-reviewed journals to be certain they're of sufficient quality to draw reliable conclusions from.

However, the company's founder and research director, Nikolai Petrovsky, said it has submitted a paper on its mice and ferret studies and is awaiting acceptance.

Based on this unpublished pre-clinical work, this vaccine was assessed in a phase 1 human trial that started June 30 last year.

Clinical trials normally go through three phases:

• phase 1 trials are the first trials in humans, typically small and predominantly focused on safety

• phase 2 trials are a little larger, still mostly focused on safety but we start to look a little more at how well it actually works

• phase 3 are larger studies, looking still at safety but focused mainly on how effectively the vaccine reduces infection or disease.

In Vaxine's phase 1 trial, 40 participants aged 18 to 65 were included, with 30 people receiving the active vaccine and ten getting a saline placebo.

The company's website says preliminary data of this phase 1 study demonstrated the COVAX-19 vaccine is safe, well tolerated and produces an immune response, though its data on this trial isn't published.

Petrovsky said this data has also been submitted and is awaiting acceptance. He said the company's main focus is on advancing the clinical trials and preparing to produce hundreds of millions of doses, if successful.

He added "we just don't have the luxury of lots of surplus bandwidth to be writing and publishing papers at the same time."

The phase 2 clinical trials started on May 30 in Iran, with 400 volunteers injected with either a placebo or the first dose of the vaccine candidate.

This is a step in the right direction. But even if the published phase 1 results confirm the safety and efficacy, given the phase 2 trial has only just commenced and large phase 3 trials are still required, it will unfortunately be some time before we know whether it's a safe and effective vaccine.

How quickly the vaccine could be available is also likely to depend largely on Vaxine's ability to scale up manufacturing, which takes considerable investment and quite a long period of time.

Source

Two mRNA vaccines against COVID-19 have proven safe and effective in clinical trials, as well as in the millions of people who have been vaccinated so far. But how prior SARS-CoV-2 infection affects vaccine response, and how long that response lasts, are still uncertain. Now, a new study in ACS Nano supports increasing evidence that people who had COVID-19 need only one vaccine dose, and that boosters could be necessary for everyone in the future.

In clinical trials, the Pfizer-BioNTech and Moderna COVID-19 vaccines were about 95% effective in protecting against symptomatic infections. Both mRNA vaccines trigger the immune system to produce antibodies against the SARS-CoV-2 spike protein receptor binding domain (RBD), and two doses are necessary to provide immunity in people who haven't previously had COVID-19.

However, the clinical trials included very few people who had already recovered from the disease, so the immune response of these individuals is less well known. Also, the time course of antibody development in both groups, and how long virus-neutralizing antibodies persist, haven't been well characterized. So Otto Yang and colleagues wanted to compare antibody levels, quality and persistence after one and two doses of mRNA vaccine in people with or without prior SARS-CoV-2 infection.

The researchers used an enzyme-linked immunosorbent assay (ELISA) to measure antibodies against the RBD in people who received the Pfizer-BioNTech or Moderna vaccine, and in unvaccinated people soon after mild or severe COVID-19 cases. In the 28 participants without prior infection, one dose of either vaccine triggered antibody levels similar to those seen after mild COVID-19 infections, whereas two doses were required to obtain anti-RBD antibodies approaching those observed after severe cases.

In contrast, in 36 participants who had COVID-19 prior to vaccination, the first dose produced a vigorous antibody response similar to severe natural infection, but the second dose provided no additional increase in antibody levels. The quality of antibodies, indicated by their ability to neutralize the SARS-CoV-2 spike protein and their potency, followed similar patterns. After the second vaccine dose, antibody levels waned in both groups comparably to natural infection, resulting in an average loss of 90% within 85 days. Although more research on T cell responses to the vaccines is needed, this result suggests that booster vaccinations will likely be required for everyone, the researchers say.

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In two recently published research papers, computer scientists from the University of Luxembourg and international partners show how mouse movements can be used to gain additional knowledge about the user behavior. While this has many interesting applications, mouse movements can also reveal sensitive information about the users such as their age or gender. Scientists want to raise awareness about these potential privacy issues and have proposed measures to mitigate them.

Prof. Luis Leiva from the University of Luxembourg and corresponding author of the two papers explains in more details the key findings.

My mouse, my rules

"We have demonstrated how straightforward it is to capture behavioral data about the users at scale, by unobtrusively tracking their mouse cursor movements, and predict user's demographics information with reasonable accuracy using five lines of code. For years, recording mouse movements on websites has been easy, however to analyze them one would need advanced expertise in computer science and machine learning. Today, there are many libraries and frameworks that allows anyone with a minimum of programming knowledge to create rather sophisticated classifiers. This raises new privacy issues and users do not have an easy opt -out mechanism."

Credit: University of Luxembourg

Based on their results, the team developed a method to prevent mouse tracking by distorting the mouse coordinates in real-time. "It is inspired by recent research in adversarial machine learning, and has been implemented as a web browser extension, so that anyone can benefit from this work in practice," explains Leiva. The web browser extension called MouseFaker is available on Github.

This work has been presented at the 6th ACM SIGIR Conference on Human Information Interaction and Retrieval.

When choice happens

Nevertheless, mouse tracking has very practical applications for webmasters, and in particular for search engines. Dr. Ioannis Aparakis from Telefonica Research and co-author of both publications, clarifies: "When you search for something at Google or Bing, your mouse movements are sending a tiny signal to the search engine indicating if you are interested or not in the content you have been shown. As mouse tracking may have privacy issues, we investigated the possibility of recording only a small part of the whole movement trajectory and see if we can still infer how people make choices in web search."

The team analyzed three representative scenarios where users had to make a choice on web search engines: when they notice an advertisement, when they abandon the page, and when they become frustrated. The results are interesting: if users pay attention to an ad, it will be signaled by the initial mouse movements. In case of page abandonment, it is actually the opposite: the last movements inform whether the user has decided to leave either if they were satisfied with the search results or not, without having to click on anything. In the frustration case, results were mixed but it seemed the middle part of a mouse movement trajectory provides more information than the initial or final parts.

The researchers found that it is possible to predict the aforementioned tasks sometimes using just two or three seconds of mouse movement. Therefore, they conclude that, by only tracking the interesting parts, search engines could get useful information and improve their services while respecting the users' privacy. This work will be presented at the 44th International ACM SIGIR Conference on Research and Development in Information Retrieval.

Prof. Leiva says, "By efficiently recording the right amount of movement data, we can save valuable bandwidth and storage, respect the user's privacy, and increase the speed at which machine learning models can be trained and deployed. Considering the web scale, doing so will have a net benefit on our environment."

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Once-dreaded Alpha variant is falling fast—Delta and Gamma take over

The Delta coronavirus variant now accounts for 20.6 percent of cases in the US.

Two dreaded coronavirus variants are swiftly overthrowing the previously most-dreaded variant in the US. Their ascendance is making experts worry that the country could see continued outbreaks and resurgences of COVID-19 unless the current sluggish pace of vaccination quickens.

 

Alpha—the variant formerly known as B.1.1.7 and first identified in the UK—swept the country at the start of the year. It’s estimated to be around 50 percent more transmissible than the version of the pandemic coronavirus, SARS-CoV-2, that mushroomed out of Wuhan, China, in 2020. Alpha’s rise in the UK last fall was linked to a surge in cases as the virus variant quickly accounted for more than 90 percent of cases there. Likewise, in the US, Alpha became the predominant strain in a matter of months this year and accounted for around 70 percent of the circulating strains by the end of April.

 

But according to fresh data, two other variants now threaten Alpha’s reign in the US: Delta (aka B.1.617.2, first detected in India) and Gamma (aka P.1, first detected in Brazil and Japan). Delta is considered the most concerning variant seen yet. Though vaccines are still effective against Delta, the variant is estimated to be 50 percent to 60 percent more contagious than Alpha, and evidence suggests that it may cause more severe disease. When Delta first appeared in the UK at the start of April, it rapidly overcame Alpha and now accounts for around 90 percent of cases. Gamma, on the other hand, is not such a rapid spreader, but it does slightly knock back the effectiveness of vaccines.

 

According to the data posted online Monday on a preprint server, Delta and Gamma are wasting no time collectively overtaking Alpha in the US, which has already fallen from dominance. Alpha dropped from 70 percent of cases in April to its current low of around 35 percent. In the preprint study, Delta and Gamma collectively made up around 30 percent of all case in the US as of June 9, with Delta making up around 14 percent of cases and Gamma making up around 16 percent.

 

Data from the Centers for Disease Control and Prevention presented in a White House press conference Tuesday estimate that, as of June 19, Delta’s share of cases nationwide is now up to 20.6 percent.

The preprint study, which has not been peer-reviewed, was run by California-based researchers at the genomics company Helix. The company is working with the CDC to help monitor SARS-CoV-2 variants. Helix researchers had data on nearly 244,000 positive SARS-CoV-2 samples collected since January 2021. And they had the genetic sequences of nearly 20,000 virus isolates collected across 747 counties nationwide since April.

 

The study has limitations, most notably the smaller number of samples collected in recent weeks given a welcomed slowdown in transmission. Though the authors suggest their data set shouldn’t be biased toward any specific variant, they do note that the samples “do not proportionally represent the different areas of the United States by population.” About 25 percent of the samples were collected from Florida, for instance. However, when they did break out analyses, they could still see nationwide trends.

 

Overall, the data was clear that Delta and Gamma are taking over. And Delta in particular is spreading the fastest. It is outpacing Gamma and set to become the predominant variant in the US, as it did in the UK.

 

Still, both variants have advantages. When the researchers looked at how the two variants were spreading in various counties, they found that:

The growth curve for [Delta], which is more transmissible but against which vaccines are highly effective, shows faster growth in counties with lower vaccination rates. In contrast, [Gamma], which is less transmissible but against which vaccines have somewhat less efficacy, has a higher prevalence in counties with higher vaccination rates.

The data supports experts’ calls for people to get vaccinated and for vaccinated people to remain vigilant. In the White House press briefing Tuesday, top infectious disease expert Anthony Fauci echoed the concern, calling Delta the “greatest threat” to the country’s path out of the pandemic.

Fauci noted that 34 states have less than 70 percent of their adult populations vaccinated. There’s a “real danger,” Fauci said, that the Delta variant could drive local surges in COVID-19 cases into the fall in places with low vaccination rates.

 

“Conclusion: We have the tools,” he said, referring to effective vaccines, “so let’s use them and crush the outbreak.”

Once-dreaded Alpha variant is falling fast—Delta and Gamma take over

Scientists at the University of North Carolina Gillings School of Global Public Health have developed a universal vaccine that protected mice not just against COVID-19 but also other coronaviruses and triggered the immune system to fight off a dangerous variant.

While no one knows which virus may cause the next outbreak, coronaviruses remain a threat after causing the SARS outbreak in 2003 and the global COVID-19 pandemic.

To prevent a future coronavirus pandemic, UNC-Chapel Hill researchers designed the vaccine to provide protection from the current SARS-CoV-2 coronavirus and a group of coronaviruses known to make the jump from animals to humans.

The findings were published in Science by lead authors David Martinez, a postdoctoral researcher at UNC Gillings School of Global Public Health and a Hanna H. Gray Fellow at the Howard Hughes Medical Institute, and Ralph Baric, an epidemiologist at UNC Gillings School of Global Public Health and professor of immunology and microbiology at the UNC School of Medicine, whose research has sparked new therapies to fight emerging infectious diseases.

The lead authors worked with a team of scientists from UNC-Chapel Hill, Duke University School of Medicine, and the University of Pennsylvania Perelman School of Medicine.

Researchers at UNC-Chapel Hill are playing a key role in coronavirus vaccine development. After testing the effectiveness of the first generation of COVID-19 vaccines, they pivoted to look at a second-generation vaccine: one that targets sarbecoviruses, Baric said.

Sarbecoviruses, part of the large family of coronaviruses, are a priority for virologists after two caused devastating disease in the past two decades: SARS and COVID-19.

The team's approach started with mRNA, which is similar to the Pfizer and Moderna vaccines used today. But instead of including the mRNA code for only one virus, they welded together mRNA from multiple coronaviruses.

When given to mice, the hybrid vaccine effectively generated neutralizing antibodies against multiple spike proteins—which viruses use to latch onto healthy cells, including one associated with B.1.351, known as the South African variant.

"The vaccine has the potential to prevent outbreaks when used as a new variant is detected," said Baric, a trailblazer in pandemic preparedness.

The paper includes data from mice infected with SARS-CoV and related coronaviruses and the vaccine prevented infection and lung damage in mice. Additional testing could lead to human clinical trials next year.

"Our findings look bright for the future because they suggest we can design more universal pan coronavirus vaccines to proactively guard against viruses we know are at risk for emerging in humans," Martinez said. "With this strategy, perhaps we can prevent a SARS-CoV-3."

Source

Sydney was battling a fresh COVID-19 cluster on Tuesday just as Melbourne's latest outbreak receded, highlighting Australia's difficulty in quashing persistent small virus flare-ups.

Ten people were diagnosed with COVID-19 in Sydney overnight, taking the cluster that first emerged in the city's Bondi Beach area last week to 21 cases.

New South Wales state Premier Gladys Berejiklian said health officials expected the outbreak in Australia's most populous city to continue growing in the coming days, after several people were infected in just "fleeting" non-physical contact with a case in a cafe and a large shopping centre.

In response, the government has reimposed mandatory mask-wearing in public transport and retail outlets across much of greater Sydney, but it has stopped short of ordering a lockdown.

The outbreak is thought to have started when a man who works as a driver for international flight crews contracted the highly contagious Delta variant of the virus, which was first identified in India.

"We also need to recognise that this Delta variant... is actually a gold medallist when it comes to jumping from one person to another," Berejiklian told reporters in Sydney.

It comes as restrictions on Melbourne's five million residents continued easing, with new cases slowing to a trickle in recent days.

New Zealand and several Australian states have announced the removal of travel restrictions imposed last month as dozens of cases were detected in Melbourne and the city endured a two-week lockdown.

Canberra has maintained strict international border closures since March 2020—even limiting its own citizens' travel to and from the country—in an effort to shut out COVID-19.

But the virus has repeatedly escaped hotels used to quarantine returning travellers, and health experts say the outbreaks will continue until large numbers of Australians are vaccinated.

Australia has administered 6.7 million doses to date in a population of 25 million, with only a small fraction having received both jabs.

The country has recorded about 30,000 cases of COVID-19 and 910 deaths during the pandemic.

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Cuba's Abdala coronavirus candidate vaccine showed "efficacy" of more than 92 percent after three doses, its maker said Monday, though it did not specify whether this was measured against infection, disease, or death.

Cuba is working on five coronavirus vaccines, and last month started immunizing its population using two of them yet to complete clinical trials.

On Monday, the BioCubaFarma laboratory tweeted that Abdala—one of the two already in use— "shows an efficacy of 92.28 percent in its three-dose scheme".

The World Health Organization has set a 50-percent efficacy threshold for coronavirus vaccines to offer protection against the virus or disease.

The announcement came two days after authorities announced that Soberana 2, the other three-dose shot being developed in Cuba, was 62 percent effective after the first two shots.

Cuban President Miguel Diaz-Canel welcomed the news as an achievement which "will multiply pride" in the communist island nation.

Cuba has been relatively unscathed by the outbreak but has seen a recent sharp increase in cases, registering one of its worst days Monday with 1,561 confirmed infections in 24 hours. To date, it has recorded just over 169,000 cases and 1,170 deaths.

Under American sanctions, Cuba has a long tradition of making its own vaccines, dating back to the 1980s.

Nearly 80 percent of its vaccines are produced locally and it hopes to come up with the first locally-produced coronavirus shot in Latin America.

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Drinking coffee that is caffeinated (ground or instant) or decaffeinated is associated with a reduced risk of developing chronic liver disease and related liver conditions, according to a study published in the open access journal BMC Public Health.

Researchers at the Universities of Southampton and Edinburgh, UK, found that drinking any type of coffee was associated with a reduced risk of developing and dying from chronic liver disease compared to not drinking coffee, with the benefit peaking at three to four cups per day.

The authors studied UK Biobank data on 495,585 participants with known coffee consumption, who were followed over a median of 10.7 years to monitor who developed chronic liver disease and related liver conditions.

Of all participants included in the study, 78% (384,818) consumed ground or instant caffeinated or decaffeinated coffee, while 22% (109,767) did not drink any type of coffee. During the study period, there were 3,600 cases of chronic liver disease, including 301 deaths. Additionally, there were 5,439 cases of chronic liver disease or steatosis (a build of up fat in the liver also known as fatty liver disease), and 184 cases of Hepatocellular carcinoma, a type of liver cancer.

Compared to non-coffee drinkers, coffee-drinkers had a 21% reduced risk of chronic liver disease, a 20% reduced risk of chronic or fatty liver disease, and a 49% reduced risk of death from chronic liver disease. The maximum benefit was seen in the group who drank ground coffee, which contains high levels of the ingredients Kahweol and cafestol, which have been shown to be beneficial against chronic liver disease in animals.

Instant coffee, which has low levels of Kahweol and cafestol was also associated with a reduced the risk of chronic liver disease. While the reduction in risk was smaller than that associated with ground coffee, the finding may suggest that other ingredients, or potentially a combination of ingredients, may be beneficial.

Dr. Oliver Kennedy, the lead author said: "Coffee is widely accessible and the benefits we see from our study may mean it could offer a potential preventative treatment for chronic liver disease. This would be especially valuable in countries with lower income and worse access to healthcare and where the burden of chronic liver disease is highest."

The authors caution that, as coffee consumption was only reported when participants first enrolled in the study, the study does not account for any changes in the amount or type of coffee they consumed over the 10.7-year study period. As participants were predominantly white and from a higher socio-economic background, the findings may be difficult to generalize to other countries and populations.

The authors suggest that future research could test the relationship between coffee and liver disease with more rigorous control of the amount of coffee consumed. They also propose validating their findings in more diverse groups of participants.

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In two separate articles in the Annals of Neurology, clinicians in India and England report cases of a rare neurological disorder called Guillain-Barré syndrome after individuals were vaccinated against COVID-19.

Both reports describe an unusual variant of Guillain-Barré syndrome characterized by prominent facial weakness. Seven cases were reported from a regional medical center in Kerala, India, where approximately 1.2 million people were vaccinated with the AstraZeneca COVID-19 vaccine. Four cases were reported from Nottingham, England, in an area in which approximately 700,000 people received the same vaccine. All eleven cases were among people who had received that vaccine between 10 and 22 days earlier.

The frequency of Guillain-Barré syndrome in these areas was estimated to be up to 10 times greater than expected.

"If the link is causal it could be due to a cross-reactive immune response to the SARS-CoV-2 spike protein and components of the peripheral immune system," wrote the authors of the report from England.

The authors of both articles stress that clinicians should be vigilant in looking for this rare neurological syndrome following administration of COVID-19 vaccines.

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NASSCOM says industry has already weathered the worst automation has to offer, but may use different definitions of where jobs are at risk

India’s National Association of Software and Service Companies (NASSCOM) has strongly criticised a Bank of America prediction that automation would cause three million job losses in its industry.

NASSCOM late last week published [PDF] a document diplomatically says the Bank of America (BoA) report “has some great insights on the Future of Work and other emerging trends.”

But the rebuttal document quickly adopts a sharper tone, accusing BoA of basic errors such as overcounting the number of people who work in business process management in India: the shortened public version of the report said India stands to lose 30 per cent of jobs in “back-office IT work”. NASSCOM’s rebuttal says the business process management (BPM) sector employs 1.4 million people while the “IT-BPM sector” employs 4.5 million.

NASSCOM adds that around a third of jobs in the BOM sector are related to customer interaction services. “Most of the customer work from India is now being done in an omni-channel model and involves higher-end expertise with technology and automation already built into the processes,” the Association wrote, suggesting that automation has already had its way with the industry.

The Association also points out that delivering automation projects for customers is a massive opportunity for India’s services companies, and that those companies are collectively hiring at a rate of over 100,000 people a year in India alone.

It is unclear if NASSCOM is referring to the redacted version of the document that BoA published, or has been able to access the complete version. The redacted version of the BoA report does not mention business process automation or customer service work. It does, however, cite research that automatic teller machines initially led to job cuts in retail banking, but then spurred jobs growth by reducing the costs of running a bank branch and making it possible for banks to open more retail locations.

“Although today we are seeing another round of disruption on retail bank branches via mobile payments,” the BoA report states, “the growing role of fintech could spur job creation to help offset job losses for the bank tellers of today.” ®

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Health care experts urge increased awareness of obstructive sleep apnea among people with cardiovascular disease or risk factors such as high blood pressure, according to a new scientific statement from the American Heart Association, published today in Circulation.

Obstructive sleep apnea (OSA) occurs in 40% to 80% of people with cardiovascular disease, yet it is under-recognized and undertreated, according to the statement. OSA occurs when an upper airway obstruction causes repeated episodes of disrupted breathing during sleep. Symptoms include snoring, lapses in breathing, fragmented sleep and daytime sleepiness. In general, about 34% of middle-aged men and 17% of middle-aged women meet the criteria for OSA.

"Obstructive sleep apnea can negatively impact patients' health and increase the risk of cardiovascular events and death. This statement is to encourage increased awareness, screening and treatment as appropriate for sleep apnea," said Chair of the scientific statement writing group Yerem Yeghiazarians, M.D., FAHA, professor of medicine and the Leone-Perkins Family Endowed Chair in Cardiology at the University of California, San Francisco. 

Risk factors for OSA include obesity, large neck circumference, craniofacial abnormalities, smoking, family history and nighttime nasal congestion. OSA is associated with several cardiovascular complications, as detailed in Figure 2 of the statement:

• high blood pressure—OSA is present in 30-50% of people with high blood pressure, and up to 80% of those who have resistant, or hard-to-treat high blood pressure;

• heart rhythm disorders such as atrial fibrillation and sudden cardiac death;

• Stroke;

• worsening heart failure;

• worsening coronary artery disease and risk of heart attack;

• Pulmonary hypertension (PH) – as many as 80% of people with PH have OSA; and

• Metabolic syndrome and Type 2 diabetes.

While there's no consensus that screening for OSA alters clinical outcomes, the high prevalence of OSA among people with cardiovascular disease, along with evidence that OSA treatment improves patient quality of life, are reasons to screen and provide treatment, according to the statement writing group.

"Patients report better mood, less snoring, less daytime sleepiness, improved quality of life  and work productivity with OSA treatment," Yeghiazarians said. "In addition, screening advances have changed how we diagnose and treat obstructive sleep apnea. For example, many patients do not have to go to an overnight sleep study center anymore. There are now sleep devices approved by the FDA that patients use at home and send back to their doctor for assessment. And, while a continuous positive airway pressure (CPAP) machine is one form of treatment, there are numerous therapeutic options—from positional therapy and weight loss to oral appliances and surgery—depending on the cause and severity of someone's OSA."

The authors suggest:

• Screening for OSA in patients with resistant or difficult to control hypertension, pulmonary hypertension and atrial fibrillation that recurs despite treatment.

• Screening for OSA via a sleep study for some patients with heart failure, especially if sleep-disordered breathing or excessive daytime sleepiness are suspected.

• Treating patients diagnosed with OSA with available therapies, potentially including lifestyle and behavior modifications and weight loss.

• When possible, treating patients with severe OSA with a CPAP machine.

• Treating mild to moderate OSA cases with oral appliances that adjust the jaw and tongue placement during sleep to prevent obstructed breathing.

• Routine follow-up including overnight sleep testing to confirm if treatment is effective.

"Improvements in home diagnostic tools and more research on ways to identify cardiovascular risk in people with OSA are needed," Yeghiazarians said. "Still, the overall message is clear: we need to increase awareness about screening for and treating OSA, especially in patients with existing cardiovascular risk factors."

This scientific statement was prepared by the volunteer writing group on behalf of the American Heart Association's Council on Clinical Cardiology; the Council on Peripheral Vascular Disease; the Council on Arteriosclerosis, Thrombosis and Vascular Biology; the Council on Cardiopulmonary, Critical Care, Perioperative and Resuscitation; the Stroke Council; and the Council on Cardiovascular Surgery and Anesthesia. 

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Australian children are among the least active in the world. In a recent study, Aussie kids ranked 140th out of 146 countries for physical activity.

And in 2018, a physical activity "report card" gave Australian children a D-minus for overall physical activity levels. The grade was based on only 18% of young people meeting the physical activity guidelines—60 minutes of moderate-to-vigorous physical activity each day.

We developed and tested a program that trains teachers and schools to enhance the physical activity of their students long-term. And it costs just a fraction of some government policies that have shown limited results.

Government policies not meeting their goals

State policies typically require primary schools to provide students with at least two hours of planned physical activity each week. This doesn't just have to be physical education classes and can include sport, energiser breaks and more active lessons. Still, many schools fail to meet these recommendations.

Australian children's competency in fundamental movements are alarmingly low. For example, governments recommend children master an overarm throw by year 4 because it's a gateway to many sports. Yet, evidence suggests 75% of year 6 girls have still failed to master this skill.

To address these problems, schools and governments have spent a lot of money on attempting to increase physical activity in kids.

For example, the New South Wales government recently spent $207 million over four years to subsidize children who enroll in sport outside of school. The Active Kids policy gives each eligible child a $100 voucher for the cost of sports registration, membership expenses and fees for physical activities such as swimming, dance lessons and athletics.

These vouchers do appear to be effective for children who use them. But an evaluation showed a substantial number of parents in socially disadvantaged groups didn't know about the program, or just weren't engaging with it. This is arguably the group who needs them most.

Plus, the vouchers cover only a few hours of sport per week. Children spend the rest of their time with their parents and teachers. And we know 85% of Australian adults don't meet the required physical activity guidelines.

Teachers can be trained to help

Teachers have a lot on their plates, but equipping teachers to promote physical activity can have long-lasting benefits. Teachers can pass on new skills to thousands of students over their career.

Training teachers led to more student physical activity, higher fitness, and better mastery of key skills.

The skills teachers can learn don't have to be complicated. For example:

• well-meaning teachers may spend more than half of their physical education lessons with children being inactive, such as when giving instructions. Lessons could jump into active games that require minimal instruction

• classroom teachers can add five-minute "energiser breaks" of physical activity between lessons

• schools could make recess and lunch more active with a few hundred dollars of equipment or setting up games with the equipment they already have.

Many teachers already use some of these strategies, but promoting them more widely is a cost-effective way of getting children moving without compromising other school priorities.

How we know it works

We compared the fitness of students that received a specific intervention in four primary schools, with students in four primary schools that carried on as usual. In total, 25 classes including 460 children participated in the study (199 children in the intervention group and 261 in control group).

The interventions involved several phases, including training teachers in strategies such as the ones above, giving kids awards for progress and enhancing school policies themselves to encourage fitness. We provided some basic equipment to schools like balls, markers and sashes.

In the schools that received the interventions, students' fitness, physical activity, and fundamental movement skills improved significantly more than in the schools that carried on as usual. That is, children spent about 13 more minutes per day doing moderate-to-vigorous activity (huffing and puffing) and, as a result, were better at running, throwing, jumping and catching.

To make things cheaper and easier to scale, we then moved most of the teacher professional learning online, and used some digital technologies to give teachers extra feedback. Teachers received some face-to-face support, with specialist physical education teachers giving each teacher an hour of mentoring.

Our revised program, iPLAY, doubled the usual fitness gains children got over a two-year period. It worked twice as well in children from lower socioeconomic backgrounds, and it only cost $16.50 per student per year.

Being so affordable, our small team was able to deliver the training to 189 Australian schools.

Our calculations show we could improve the health of Australia's 2 million primary school children for just one-third of the the cost of the four-year Active Kids program in NSW.

And, by supporting teachers, we are building capacity in schools for the long-term.

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A growing body of research suggests that our bodies function optimally when we align our eating patterns with our circadian rhythms.

Nutrition scientists have long debated the best diet for optimal health. But now some experts believe that it’s not just what we eat that’s critical for good health, but when we eat it.

A growing body of research suggests that our bodies function optimally when we align our eating patterns with our circadian rhythms, the innate 24-hour cycles that tell our bodies when to wake up, when to eat and when to fall asleep. Studies show that chronically disrupting this rhythm — by eating late meals or nibbling on midnight snacks, for example — could be a recipe for weight gain and metabolic trouble.

That is the premise of a new book, “The Circadian Code,” by Satchin Panda, a professor at the Salk Institute and an expert on circadian rhythms research. Dr. Panda argues that people improve their metabolic health when they eat their meals in a daily 8- to 10-hour window, taking their first bite of food in the morning and their last bite early in the evening.

This approach, known as early time-restricted feeding, stems from the idea that human metabolism follows a daily rhythm, with our hormones, enzymes and digestive systems primed for food intake in the morning and afternoon. Many people, however, snack and graze from roughly the time they wake up until shortly before they go to bed. Dr. Panda has found in his research that the average person eats over a 15-hour or longer period each day, starting with something like milk and coffee shortly after rising and ending with a glass of wine, a late night meal or a handful of chips, nuts or some other snack shortly before bed.

That pattern of eating, he says, conflicts with our biological rhythms.

Scientists have long known that the human body has a master clock in the brain, located in the hypothalamus, that governs our sleep-wake cycles in response to bright light exposure. A couple of decades ago, researchers discovered that there is not just one clock in the body but a collection of them. Every organ has an internal clock that governs its daily cycle of activity.

During the day, the pancreas increases its production of the hormone insulin, which controls blood sugar levels, and then slows it down at night. The gut has a clock that regulates the daily ebb and flow of enzymes, the absorption of nutrients and the removal of waste. The communities of trillions of bacteria that comprise the microbiomes in our guts operate on a daily rhythm as well. These daily rhythms are so ingrained that they are programmed in our DNA: Studies show that in every organ, thousands of genes switch on and switch off at roughly the same time every day.

“We’ve inhabited this planet for thousands of years, and while many things have changed, there has always been one constant: Every single day the sun rises and at night it falls,” Dr. Panda said. “We’re designed to have 24-hour rhythms in our physiology and metabolism. These rhythms exist because, just like our brains need to go to sleep each night to repair, reset and rejuvenate, every organ needs to have down time to repair and reset as well.”

Most of the evidence in humans suggests that consuming the bulk of your food earlier in the day is better for your health, said Dr. Courtney Peterson, an assistant professor in the department of nutrition sciences at the University of Alabama at Birmingham. Dozens of studies demonstrate that blood sugar control is best in the morning and at its worst in the evening. We burn more calories and digest food more efficiently in the morning as well.

At night, the lack of sunlight prompts the brain to release melatonin, which prepares us for sleep. Eating late in the evening sends a conflicting signal to the clocks in the rest of the body that it’s still daytime, said Dr. Peterson.

“If you’re constantly eating at a time of day when you’re not getting bright light exposure, then the different clock systems become out of sync,” she said. “It’s like one clock is in the time zone of Japan and the other is in the U.S. It gives your metabolism conflicting signals about whether to rev up or rev down.”

Most people know what happens when we disrupt the central clock in our brains by flying across multiple time zones or burning the midnight oil: Fatigue, jet lag and brain fog set in. Eating at the wrong time of day places similar strain on the organs involved in digestion, forcing them to work when they are programmed to be dormant, which can increase the risk of disease, said Paolo Sassone-Corsi, the director of the Center for Epigenetics and Metabolism at the University of California, Irvine.

“It’s well known that by changing or disrupting our normal daily cycles, you increase your risk of many pathologies,” said Dr. Sassone-Corsi, who recently published a paper on the interplay between nutrition, metabolism and circadian rhythms.

A classic example of this is shift workers, who account for about 20 percent of the country’s work force. Many frequently work overnight shifts, forcing them to eat and sleep at odd times. Nighttime shift work is linked to obesity, diabetes, some cancers and heart disease. While socioeconomic factors are likely to play a role, studies suggest that circadian disruption can directly lead to poor health.

In one experiment, scientists found that assigning healthy adults to delay their bedtimes and wake up later than normal for 10 days — throwing their circadian rhythms and their eating patterns out of sync — raised their blood pressure and impaired their insulin and blood sugar control. Another study found that forcing people to stay up late just a few nights in a row resulted in quick weight gain and reduced insulin sensitivity, changes linked to diabetes.

In 2012, Dr. Panda and his colleagues at the Salk Institute took genetically identical mice and split them into two groups.

One had round-the-clock access to high-fat, high-sugar foods. The other ate the same foods but in an eight-hour daily window. Despite both groups consuming the same amount of calories, the mice that ate whenever they wanted got fat and sick while the mice on the time-restricted regimen did not: They were protected from obesity, fatty liver and metabolic disease.

Inspired by this research, Dr. Peterson conducted a tightly controlled experiment in a small group of prediabetic men. In one phase of the study, the subjects ate their meals in a 12-hour daily window for five weeks. In the other phase, they were fed the same meals in a six-hour window beginning each morning. The researchers had the subjects eat enough food to maintain their weight so they could assess whether the time-restricted regimen had any health benefits unrelated to weight loss.

It did. On the time-restricted regimen, the men had lower insulin, reduced levels of oxidative stress, less nighttime hunger and significantly lower blood pressure. Their systolic pressure, the top number, fell by roughly 11 points, and their diastolic pressure dropped by 10 points.

“It was a pretty large effect,” Dr. Peterson said. “It was exciting but also shocking.”

While studies suggest that eating earlier in the day is optimal for metabolic health, it does not necessarily mean that you should skip dinner. It might, however, make sense to make your dinners relatively light. One group of researchers in Israel found in studies that overweight adults lost more weight and had greater improvements in blood sugar, insulin and cardiovascular risk factors when they ate a large breakfast, modest lunch and small dinner compared to the opposite: A small breakfast and a large dinner. Dr. Peterson said it confirms an age-old adage: Eat breakfast like a king, lunch like a prince and dinner like a pauper.

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