Scientists at Northwestern University found that people became less sensitive to food odors based on the meal they had eaten just before. These findings show that just as smell regulates what we eat, what we eat -- in turn -- regulates our sense of smell. Phys.Org reports: The study found that participants who had just eaten a meal of either cinnamon buns or pizza were less likely to perceive "meal-matched" odors, but not non-matched odors. The findings were then corroborated with brain scans that showed brain activity in parts of the brain that process odors was altered in a similar way. Feedback between food intake and the olfactory system may have an evolutionary benefit, said senior and corresponding study author Thorsten Kahnt, an assistant professor of neurology and psychiatry and behavioral sciences at Northwestern University Feinberg School of Medicine. "If you think about our ancestors roaming the forest trying to find food, they find and eat berries and then aren't as sensitive to the smell of berries anymore," Kahnt said. "But maybe they're still sensitive to the smell of mushrooms, so it could theoretically help facilitate diversity in food and nutrient intake." Kahnt said while we don't see the hunter-gatherer adaptation come out in day-to-day decision-making, the connection between our nose, what we seek out and what we can detect with our nose may still be very important. If the nose isn't working right, for example, the feedback loop may be disrupted, leading to problems with disordered eating and obesity. There may even be links to disrupted sleep, another tie to the olfactory system the Kahnt lab is researching. Kahnt said with a better understanding of the feedback loop between smell and food intake, he's hoping to take the project full circle back to sleep deprivation to see if lack of sleep may impair the loop in some way. He added that with brain imaging, there are more questions about how the adaptation may impact sensory and decision-making circuits in the brain. The study has been published in the journal PLOS Biology.

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An anonymous reader quotes a report from ScienceAlert: An artery that temporarily runs down the center of our forearms while we're still in the womb isn't vanishing as often as it used to, according to researchers from Flinders University and the University of Adelaide in Australia. That means there are more adults than ever with what amounts to be an extra channel of vascular tissue flowing under their wrist. "Since the 18th century, anatomists have been studying the prevalence of this artery in adults and our study shows it's clearly increasing," Flinders University anatomist Teghan Lucas said in 2020. "The prevalence was around 10 percent in people born in the mid-1880s compared to 30 percent in those born in the late 20th century, so that's a significant increase in a fairly short period of time, when it comes to evolution." To compare the prevalence of this persistent blood channel, Lucas and colleagues Maciej Henneberg and Jaliya Kumaratilake from the University of Adelaide examined 80 limbs from cadavers, all donated by Australians of European descent. The donors raged from 51 to 101 on passing, which means they were nearly all born in the first half of the 20th century. Noting down how often they found a chunky median artery capable of carrying a good supply of blood, the research team compared the figures with records dug out of a literature search, taking into account tallies that could over-represent the vessel's appearance. Their results were published in 2020 in the Journal of Anatomy. The fact the artery seems to be three times as common in adults today as it was more than a century ago is a startling find that suggests natural selection is favoring those who hold onto this extra bit of bloody supply.

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An anonymous reader quotes a report from New Scientist, written by Matthew Sparkes: Ant colonies can descend several meters underground, house millions of insects and last for decades, despite being made without the benefit of machinery and reinforcing material. The secrets of these impressive architectural structures are being revealed by three-dimensional X-ray imaging and computer simulations, and could be used to develop robotic mining machines. Jose Andrade at the California Institute of Technology and his colleagues set up miniature ant colonies in a container holding 500 milliliters of soil and 15 western harvester ants (Pogonomyrmex occidentalis). The position of every ant and every grain of soil was then captured by high-resolution X-ray scans every 10 minutes for 20 hours. The X-ray results gave researchers exact details about the shape of each tunnel and which grains were being removed to create it. The team then created a computer model using those scans to understand the forces acting upon the tunnels. The size, shape and orientation of every grain was recreated in the model and the direction and size of force on each grain could be calculated, including gravity, friction and cohesion caused by humidity. The model was accurate to the 0.07 millimeter resolution of the scanner. The results suggest that forces within the soil tend to wrap around the tunnel axis as ants excavate, forming what the team call "arches" in the soil that have a greater diameter than the tunnel itself. This reduces the load acting on the soil particles within the arches, where the ants are constructing their tunnel. As a result, the ants can easily remove these particles to extend the tunnel without causing cave-ins. The arches also make the tunnel stronger and more durable. "We had naively thought that ants perhaps were playing Jenga, that they were tapping, maybe they were wiggling grains, maybe they were even grabbing the grains of least resistance," says Andrade. He says it is now clear that the ants appear to know nothing about forces and show no signs of decision-making, but instead follow a very simple behavioral algorithm that has evolved over time. The ants tend to dig relatively straight tunnels that descend at the angle of repose -- the slope at which a granular material naturally forms mounds -- which was around 40 degrees in this case. They also pick exactly the right grains to remove to create a protective arch above. "In a remarkable way -- in a rather, you know, serendipitous way -- they've stumbled upon a technique for digging that is in line with the laws of physics, but incredibly efficient," says Andrade. The team believes that if the behavioral algorithm can be further analyzed and ultimately replicated, then it may find application in automated mining robots, either here on Earth or on other planetary bodies where the already risky business of mining would be even more dangerous for humans. The findings have been published in the journal Proceedings of the National Academy of Sciences.

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According to a new paper published in the Proceedings of the Royal Society B, cuttlefish appear able to recall the time and place of their meals -- and their capability doesn't decrease as they get older. Ars Technica reports: This latest study focuses on whether cuttlefish have some form of episodic memory -- the ability to recall unique past events with context about what happened, where it happened, and when it happened. Human beings develop this capability around age 4, and our episodic memory declines as we advance into old age. That's in contrast to "semantic memory," our ability to recall general learned knowledge without the context of space and time. Semantic learning in humans has been shown to remain relatively intact with advancing age. Cuttlefish lack a hippocampus, but they do have their own distinctive brain structure and organization, complete with a vertical lobe that shows similarities to the connectivity and function of the human hippocampus -- i.e., learning and memory. Past studies have shown that cuttlefish are sufficiently future-oriented that they can optimize foraging behavior and can remember details of what, where, and when from past forages -- hallmarks of episodic-like memory -- adjusting their strategy in response to changing prey conditions. But does that ability remain constant with age? [Co-author Alexandra Schnell of the University of Cambridge] et al. developed a series of semantic and episodic memory tests for cuttlefish to explore that question. The relatively short life span of cuttlefish (about two years) makes them an excellent candidate for this research. For the experiments, Schnell and her colleagues used 24 common cuttlefish, half of which were young (between 10-12 months old) and half of which were old (22-24 months, apparently the equivalent of a human's 90 years). All had been reared from eggs at the Marine Biological Laboratory and were kept in individual tanks. The team first trained the cuttlefish to respond to visual cues (the waving of black and white flags) by marking specific locations in their respective tanks. As in Schnell's prior work on delayed gratification, the cuttlefish could choose their preferred prey -- in this case, either live grass shrimp or a piece of prawn meat of equal size. Over the next four weeks, the cuttlefish were taught that these two types of prey were available at specific locations (marked by the waving of the flags) after delays of either one hour (for the prawn meat) or three hours (for the preferred grass shrimp). The two feeding locations were unique for each day in order to ensure that the cuttlefish weren't merely learning a pattern. Surprisingly, Schnell et al. found that all the cuttlefish, regardless of age, were able to note which type of prey appeared first at each flagged location and were able to use that observation to figure out where to find their preferred prey at each subsequent feeding. Earlier this year, researchers found that cuttlefish could pass a cephalopod version of the famous Stanford marshmallow test: waiting a bit for their preferred prey rather than settling for a less desirable prey. "Cuttlefish also performed better in a subsequent learning test -- the first time such a link between self-control and intelligence has been found in a non-mammalian species," adds Ars.

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The World Health Organization (WHO) said on Friday it was looking for the greatest scientific minds to advise on investigations into new high-threat pathogens that jump from animals to humans and could spark the next pandemic. From a report: Launching a request for applications, it said that its Scientific Advisory Group for the Origins of Novel Pathogens would also review progress on the next studies into the origins of the SARS-CoV-2 virus that emerged in China in late 2019. "We need to bring in the best minds here. And it needs to be multi-disciplinary," Maria van Kerkhove, head of WHO's emerging diseases and zoonosis unit, told Reuters. The panel, announced by WHO director-general Tedros Adhanom Ghebreyesus in July, will be composed of 25 experts expected to meet first virtually in late September, a statement said. "In the last 20 years we've had many of these pathogens emerge or re-emerge: SARS, MERS, different avian influenzas, Zika, yellow fever and of course SARS-CoV-2," van Kerkhove said. Van Kerkhove, an American epidemiologist and WHO's technical lead on COVID-19, recalled that it took more than a year to establish that dromedary camels were the intermediary source of the Middle East Respiratory Syndrome (MERS) carried by bats.

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An anonymous reader quotes a report from ScienceDaily: Eating fructose appears to alter cells in the digestive tract in a way that enables it to take in more nutrients, according to a preclinical study from investigators at Weill Cornell Medicine and NewYork-Presbyterian. These changes could help to explain the well-known link between rising fructose consumption around the world and increased rates of obesity and certain cancers. The research, published August 18 in Nature, focused on the effect of a high-fructose diet on villi, the thin, hairlike structures that line the inside of the small intestine. Villi expand the surface area of the gut and help the body to absorb nutrients, including dietary fats, from food as it passes through the digestive tract. The study found that mice that were fed diets that included fructose had villi that were 25 percent to 40 percent longer than those of mice that were not fed fructose. Additionally, the increase in villus length was associated with increased nutrient absorption, weight gain and fat accumulation in the animals. After observing that the villi were longer, the team wanted to determine whether those villi were functioning differently. So they put mice into three groups: a normal low-fat diet, a high-fat diet, and a high-fat diet with added fructose. Not only did the mice in the third group develop longer villi, but they became more obese than the mice receiving the high-fat diet without fructose. The researchers took a closer look at the changes in metabolism and found that a specific metabolite of fructose, called fructose-1-phosphate, was accumulating at high levels. This metabolite interacted with a glucose-metabolizing enzyme called pyruvate kinase, to alter cell metabolism and promote villus survival and elongation. When pyruvate kinase or the enzyme that makes fructose-1-phospate were removed, fructose had no effect on villus length. Previous animal studies have suggested that this metabolite of fructose also aids in tumor growth. From an evolutionary standpoint, the findings make sense. "In mammals, especially hibernating mammals in temperate climates, you have fructose being very available in the fall months when the fruit is ripe," said one of the researchers. "Eating a lot of fructose may help these animals to absorb and convert more nutrients to fat, which they need to get through the winter." Humans, on the other hand, did not evolve to eat the amount of fructose they consume now.

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The world's first customer delivery of "green steel" produced without using coal is taking place in Sweden, according to its manufacturer. From a report: The Swedish venture Hybrit said it was delivering the steel to truck-maker Volvo AB as a trial run before full commercial production in 2026. Volvo has said it will start production in 2021 of prototype vehicles and components from the green steel. Steel production using coal accounts for around 8% of global greenhouse gas emissions. Hybrit started test operations at its pilot plant for green steel in Lulea, northern Sweden, a year ago. It aims to replace coking coal, traditionally needed for ore-based steel making, with renewable electricity and hydrogen. Hydrogen is a key part of the EU's plan to reach net zero greenhouse gas emissions by 2050.

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An anonymous reader quotes a report from ScienceAlert: Mini brains grown in a lab from stem cells have spontaneously developed rudimentary eye structures scientists report in a fascinating new paper. On tiny, human-derived brain organoids grown in dishes, two bilaterally symmetrical optic cups were seen to grow, mirroring the development of eye structures in human embryos. This incredible result will help us to better understand the process of eye differentiation and development, as well as eye diseases. Brain organoids are not true brains, as you might be thinking of them. They are small, three-dimensional structures grown from induced pluripotent stem cells -- cells harvested from adult humans and reverse engineered into stem cells, that have the potential to grow into many different types of tissue. In this case, these stem cells are coaxed to grow into blobs of brain tissue, without anything resembling thoughts, emotions, or consciousness. Such 'mini brains' are used for research purposes where using actual living brains would be impossible, or at the very least, ethically tricky -- testing drug responses, for example, or observing cell development under certain adverse conditions. Previous work in the development of organoids showed evidence of retinal cells, but these did not develop optic structures, so the team changed their protocols. They didn't attempt to force the development of purely neural cells at the early stages of neural differentiation, and added retinol acetate to the culture medium as an aid to eye development. Their carefully tended baby brains formed optic cups as early as 30 days into development, with the structures clearly visible at 50 days. This is consistent with the timing of eye development in the human embryo, which means these organoids could be useful for studying the intricacies of this process. There are other implications, too. The optic cups contained different retinal cell types, which organized into neural networks that responded to light, and even contained lens and corneal tissue. Finally, the structures displayed retinal connectivity to regions of the brain tissue. The research has been published in the journal Cell Stem Cell.

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An anonymous reader quotes a report from The New York Times: Scientists have come tantalizingly close to reproducing the power of the sun -- albeit only in a speck of hydrogen for a fraction of a second. Researchers at Lawrence Livermore National Laboratory reported on Tuesday that by using 192 gigantic lasers to annihilate a pellet of hydrogen, they were able to ignite a burst of more than 10 quadrillion watts of fusion power -- energy released when hydrogen atoms are fused into helium, the same process that occurs within stars. Indeed, Mark Herrmann, Livermore's deputy program director for fundamental weapons physics, compared the fusion reaction to the 170 quadrillion watts of sunshine that bathe Earth's surface. "This about 10 percent of that," Dr. Herrmann said. And all of the fusion energy emanated from a hot spot about as wide as a human hair, he said. But the burst -- essentially a miniature hydrogen bomb -- lasted only 100-trillionths of a second. Still, that spurred a burst of optimism for fusion scientists who have long hoped that fusion could someday provide a boundless, clean energy source for humanity. The success also signified a moment of redemption for Livermore's football-stadium-size laser apparatus, which is named the National Ignition Facility, or N.I.F. Despite an investment of billions of dollars -- construction started in 1997 and operations began in 2009 -- the apparatus initially generated hardly any fusion at all. In 2014, Livermore scientists finally reported success, but the energy produced then was minuscule -- the equivalent of what a 60-watt light bulb consumes in five minutes. On Aug. 8, the burst of energy was much greater -- 70 percent as much as the energy of laser light hitting the hydrogen target. That is still a losing proposition as an energy source, consuming more power than it produces. But scientists are confident that further jumps in energy output were possible with fine-tuning of the experiment.

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A study of 6,400 people "from eight days old up to age 95, in 29 countries," finds that the human metabolism "peaks at the age of one, is stable from 20 to 60 and then inexorably declines," writes the BBC. Long-time Slashdot reader Hope Thelps shares their report: The study, published in the journal Science, found four phases of metabolic life: - birth to age one, when the metabolism shifts from being the same as the mother's to a lifetime high 50% above that of adults - a gentle slowdown until the age of 20, with no spike during all the changes of puberty - no change at all between the ages of 20 and 60 - a permanent decline, with yearly falls that, by 90, leave metabolism 26% lower than in mid-life "The most surprising thing for me," one of the researchers tells the BBC, "is there is no change throughout adulthood — if you are experiencing mid-life spread you can no longer blame it on a declining metabolic rate." Science magazine's headline? "Little kids burn so much energy, they're like a different species, study finds." [T]he first comprehensive study of energy use over the human life span has quantified their burn rate: Infants between the ages of 9 and 15 months expend a stunning 50% more energy in 1 day than adults do, adjusted for body size. These wee dynamos consume and use up energy even faster than pregnant women and teenage boys, most likely to fuel their energetically expensive brains and organs. "Little people are not burning energy like small adults," says Duke University evolutionary biologist Herman Pontzer, who led the new analysis of data from around the world. "They are burning energy superfast ... like a different species."

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AmiMoJo writes: Reaching herd immunity is "not a possibility" with the current Delta variant, the head of the Oxford Vaccine Group has said. Giving evidence to MPs on Tuesday, Prof Sir Andrew Pollard said the fact that vaccines did not stop the spread of Covid meant reaching the threshold for overall immunity in the population was "mythical." "The problem with this virus is [it is] not measles. If 95% of people were vaccinated against measles, the virus cannot transmit in the population," he told the all-party parliamentary group (APPG) on coronavirus. "The Delta variant will still infect people who have been vaccinated. And that does mean that anyone who's still unvaccinated at some point will meet the virus ... and we don't have anything that will [completely] stop that transmission." Although the existing vaccines are very effective at preventing serious Covid illness and death, they do not stop a fully vaccinated person from being infected by the virus that causes Covid-19. The concept of herd or population immunity relies on a large majority of a population gaining immunity -- either through vaccination or previous infection -- which, in turn, provides indirect protection from an infectious disease for the unvaccinated and those who have never been previously infected. Data from a recent React study conducted by Imperial College London suggests that fully vaccinated people aged 18 to 64 have about a 49% lower risk of being infected compared with unvaccinated people. The findings also indicated that fully vaccinated people were about half as likely to test positive after coming into contact with someone who had Covid (3.84%, down from 7.23%).

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omfglearntoplay shares a report from ScienceAlert: According to theory, if you smash two photons together hard enough, you can generate matter: an electron-positron pair, the conversion of light to mass as per Einstein's theory of special relativity. It's called the Breit-Wheeler process, first laid out by Gregory Breit and John A. Wheeler in 1934, and we have very good reason to believe it would work. But direct observation of the pure phenomenon involving just two photons has remained elusive, mainly because the photons need to be extremely energetic (i.e. gamma rays) and we don't have the technology yet to build a gamma-ray laser. Now, physicists at Brookhaven National Laboratory say they've found a way around this stumbling block using the facility's Relativistic Heavy Ion Collider (RHIC) -- resulting in a direct observation of the Breit-Wheeler process in action. The research has been published in the journal Physical Review Letters.

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A pretty little white flower that grows near urban centers of the Pacific Northwest turns out to be a killer. NPR reports: The bog-dwelling western false asphodel, Triantha occidentalis, was first described in the scientific literature in 1879. But until now, no one realized that this sweet looking plant used its sticky stem to catch and digest insects, according to researchers who note in their study published Monday that it's the first new carnivorous plant to be discovered in about 20 years. "We had no idea it was carnivorous," says Sean Graham, a botanist with the University of British Columbia. "This was not found in some exotic tropical location, but really right on our doorstep in Vancouver. You could literally walk out from Vancouver to this field site." Fewer than a thousand plant species are carnivorous, and these plants tend to live in places with abundant sun and water, but nutrient-poor soil. Graham's team was doing an unrelated project on plant genetics and noticed that the western false asphodel had a genetic deletion that's sometimes seen in carnivorous plants. The researchers started to think about the fact that this flower grew in the kind of environment that's home to various other insect-eating plants. "And then they have these sticky stems," says Graham. "So, you know, it was kind of like, hmm, I wonder if this could be a sign that this might be carnivorous." To see if the plants could actually take in nutrients from insects, researcher Qianshi Lin, now at the University of Toronto, Mississauga, fed fruit flies nitrogen-15 isotopes, so that this nitrogen could be used as a tracker. He then stuck these flies to stems of this plant. Later, an analysis showed that nitrogen from the dead insects was indeed getting into the plants. In fact, Triantha was getting more than half of its nitrogen from prey. In the Proceedings of the National Academy of Sciences published online Monday, Lin and his colleagues say that this is comparable to what's seen in other carnivorous plants. What's more, the researchers showed that the sticky hairs on the flower stalk produce a digestive enzyme that's known to be used by many carnivorous plants. And when the research team looked at specimens of this plant preserved in herbariums, they found small dead insects stuck to the stems.

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Hmmmmmm shares a report from The Independent: Scientists in China have developed the hardest and strongest glassy material known so far that can scratch diamond crystals with ease. The researchers, including those from Yanshan University in China, noted that the new material -- tentatively named AM-III -- has "outstanding" mechanical and electronic properties, and could find applications in solar cells due to its "ultra-high" strength and wear resistance. Analysis of the material, published in the journal National Science Review, revealed that its hardness reached 113 gigapascals (GPa) while natural diamond stone usually scores 50 to 70 on the same test. According to the scientists, AM-III has tunable energy absorption properties comparable to semiconductors commonly used in solar cells such as hydrogenated amorphous silicon films. While in diamond crystals, the organized internal structure of its atoms and molecules contribute to their immense strength and hardness, in AM-III the researchers found that a combination of order and disorder of its molecules give rise to its strange properties. Using fullerenes, which are materials made of hollow football-like arrangements of carbon atoms, the researchers produced different types of glassy materials with varying molecular organization among which AM-III had the highest order of atoms and molecules. Increasing the order further, the scientists observed, could potentially kill the semiconductivity and other properties that required the atoms and molecules to be chaotic.

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From a paper on PNAS [PDF]: Can entire societies become more or less depressed over time? Here, we look for the historical traces of cognitive distortions, thinking patterns that are strongly associated with internalizing disorders such as depression and anxiety, in millions of books published over the course of the last two centuries in English, Spanish, and German. We find a pronounced "hockey stick" pattern: Over the past two decades the textual analogs of cognitive distortions surged well above historical levels, including those of World War I and II, after declining or stabilizing for most of the 20th century. Our results point to the possibility that recent socioeconomic changes, new technology, and social media are associated with a surge of cognitive distortions. Individuals with depression are prone to maladaptive patterns of thinking, known as cognitive distortions, whereby they think about themselves, the world, and the future in overly negative and inaccurate ways. These distortions are associated with marked changes in an individual's mood, behavior, and language. We hypothesize that societies can undergo similar changes in their collective psychology that are reflected in historical records of language use. Here, we investigate the prevalence of textual markers of cognitive distortions in over 14 million books for the past 125 y and observe a surge of their prevalence since the 1980s, to levels exceeding those of the Great Depression and both World Wars. This pattern does not seem to be driven by changes in word meaning, publishing and writing standards, or the Google Books sample. Our results suggest a recent societal shift toward language associated with cognitive distortions and internalizing disorders.

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An anonymous reader shares a report: With their crane-like necks, spindle legs and knobbly knees, giraffes are among the best loved and most recognizable of animals. Despite their elevated stature, however, giraffes have kept their surprisingly intricate social behavior under wraps. Once perceived as humble creatures that focused solely on feeding their majestic bodies, one book from 1991 described the giraffe as "socially aloof, forming no lasting bonds with its fellows and associating in the most casual way." But new research from the University of Bristol, published Tuesday in the journal Mammal Review, suggests giraffes have been misunderstood and are in fact a highly complex and social species. The most surprising thing for me is that it has taken until 2021 to recognize that giraffes have a complex social system. We have known for decades about other species of socially complex mammal, such as elephants, primates and cetaceans, but it is baffling to me how such a charismatic and well-known species as the giraffe could have been so understudied until recently," said Zoe Muller, study author and biologist at the University Of Bristol's School of Biological Sciences.

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Researchers around the world have continued breathing new life into a retracted study, which suggested that common antihypertensive medications were harmful in patients with COVID-19. From a report: Published online on May 1, 2020 in the New England Journal of Medicine, the study relied on Surgisphere data to claim an association between renin-angiotensin-aldosterone system (RAAS) inhibitor therapy and worse outcomes in hospitalized COVID-19 patients with cardiovascular disease. The journal retracted the paper due to concerns about fraudulent data on June 4, 2020 in a widely publicized move, but the study has continued to rack up citations -- totaling at least 652 as of May 31, 2021, reported Todd Lee, MD, MPH, of McGill University in Montreal, and colleagues. Just 17.6% of verified citations acknowledged or noted that the paper was retracted, according to their research letter published in JAMA Internal Medicine. In May of this year alone -- 11 months after the article was retracted -- it was referenced 21 times. "Our findings challenge authors, peer reviewers, journal editors, and academic institutions to do a better job of addressing the broader issues of ongoing citations of retracted scientific studies and protecting the integrity of the medical literature," Lee's group urged. The hypothesis that angiotensin-converting enzyme (ACE) inhibitors and angiotensin-receptor blockers (ARBs) may be harmful in patients with COVID-19 has been floated since the early days of the pandemic, with the reasoning being that since the SARS-CoV-2 virus enters human cells through ACE2 receptors, upregulation of these receptors could put patients at risk.

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Events in the genome of Welwitschia have given it the ability to survive in an unforgiving desert for thousands of years. From a report: The longest-lived leaves in the plant kingdom can be found only in the harsh, hyperarid desert that crosses the boundary between southern Angola and northern Namibia. A desert is not, of course, the most hospitable place for living things to grow anything, let alone leafy greens, but the Namib Desert -- the world's oldest with parts receiving less than two inches of precipitation a year -- is where Welwitschia calls home. In Afrikaans, the plant is named "tweeblaarkanniedood," which means "two leaves that cannot die." The naming is apt: Welwitschia grows only two leaves -- and continuously -- in a lifetime that can last millenniums. "Most plants develop a leaf, and that's it," said Andrew Leitch, a plant geneticist at Queen Mary University of London. "This plant can live thousands of years, and it never stops growing. When it does stop growing, it's dead." Some of the largest plants are believed to be over 3,000 years old, with two leaves steadily growing since the beginning of the Iron Age, when the Phoenician alphabet was invented and David was crowned King of Israel. By some accounts, Welwitschia is not much to look at. Its two fibrous leaves, buffeted by dry desert winds and fed on by thirsty animals, become shredded and curled over time, giving Welwitschia a distinctly octopus-like look. One 19th-century director of Kew Gardens in London remarked, "it is out of the question the most wonderful plant ever brought to this country and one of the ugliest." But since it was first discovered, Welwitschia has captivated biologists including Charles Darwin and the botanist Friedrich Welwitsch after whom the plant is named: It is said that when Welwitsch first came across the plant in 1859, "he could do nothing but kneel down on the burning soil and gaze at it, half in fear lest a touch should prove it a figment of the imagination." In a study published last month in Nature Communications, researchers report some of the genetic secrets behind Welwitschia's unique shape, extreme longevity and profound resilience.

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Long-time Slashdot reader Mogster quotes : Steven Weinberg, a Nobel-prize winning physicist whose work helped link two of the four fundamental forces, has died at the age of 88, the University of Texas at Austin (UT Austin) announced Saturday (July 24). HIs work was foundational to the Standard Model, the overarching physics theory that describes how subatomic particles behave. His seminal work was a slim, three-page paper published in 1967 in the journal Physical Review Letters and entitled "A Model of Leptons." In it, he predicted how subatomic particles known as W, Z and the famous Higgs boson should behave — years before those particles were detected experimentally, according to a statement from UT Austin. The paper also helped unify the electromagnetic force and the weak force and predicted that so-called "neutral weak currents" governed how particles would interact, according to the statement. In 1979, Weinberg and physicists Sheldon Glashow and Abdus Salam earned the Nobel Prize in physics for this work. Throughout his life, Weinberg would continue his search for a unified theory that would unite all four forces, according to the statement. Weinberg also wrote a book called "The First Three Minutes: A Modern View of the Origin of the Universe" — in 1977.

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An anonymous reader quotes a report from Phys.Org: Today, the LHCb experiment at CERN is presenting a new discovery at the European Physical Society Conference on High Energy Physics (EPS-HEP). The new particle discovered by LHCb, labeled as Tcc+, is a tetraquark -- an exotic hadron containing two quarks and two antiquarks. It is the longest-lived exotic matter particle ever discovered, and the first to contain two heavy quarks and two light antiquarks. Quarks are the fundamental building blocks from which matter is constructed. They combine to form hadrons, namely baryons, such as the proton and the neutron, which consist of three quarks, and mesons, which are formed as quark-antiquark pairs. In recent years a number of so-called exotic hadrons -- particles with four or five quarks, instead of the conventional two or three -- have been found. Today's discovery is of a particularly unique exotic hadron, an exotic exotic hadron if you like. The new particle contains two charm quarks and an up and a down antiquark. Several tetraquarks have been discovered in recent years (including one with two charm quarks and two charm antiquarks), but this is the first one that contains two charm quarks, without charm antiquarks to balance them. Physicists call this "open charm" (in this case, "double open charm"). Particles containing a charm quark and a charm antiquark have "hidden charm" -- the charm quantum number for the whole particle adds up to zero, just like a positive and a negative electrical charge would do. Here the charm quantum number adds up to two, so it has twice the charm! The quark content of Tcc+, has other interesting features besides being open charm. It is the first particle to be found that belongs to a class of tetraquarks with two heavy quarks and two light antiquarks. Such particles decay by transforming into a pair of mesons, each formed by one of the heavy quarks and one of the light antiquarks. According to some theoretical predictions, the mass of tetraquarks of this type should be very close to the sum of masses of the two mesons. Such proximity in mass makes the decay "difficult," resulting in a longer lifetime of the particle, and indeed Tcc+, is the longest-lived exotic hadron found to date.

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