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    What Makes Tiny ‘Water Bears’ So Tough? They Quickly Fix Broken DNA.

    New research finds that microscopic tardigrades are remarkably good at repairing their DNA after a huge blast of radiation.To introduce her children to the hidden marvels of the animal kingdom a few years ago, Anne De Cian stepped into her garden in Paris. Dr. De Cian, a molecular biologist, gathered bits of moss, then came back inside to soak them in water and place them under a microscope. Her children gazed into the eyepiece at strange, eight-legged creatures clambering over the moss.“They were impressed,” Dr. De Cian said.But she was not finished with the tiny beasts, known as tardigrades. She brought them to her laboratory at the French National Museum of Natural History, where she and her colleagues hit them with gamma rays. The blasts were hundreds of times greater than the radiation required to kill a human being. Yet the tardigrades survived, going on with their lives as if nothing had happened.Scientists have long known that tardigrades are freakishly resistant to radiation, but only now are Dr. De Cian and other researchers uncovering the secrets of their survival. Tardigrades turn out to be masters of molecular repair, able to quickly reassemble piles of shattered DNA, according to a study published on Friday and another from earlier this year.Scientists have been trying to breach the defenses of tardigrades for centuries. In 1776, Lazzaro Spallanzani, an Italian naturalist, described how the animals could dry out completely and then be resurrected with a splash of water. In the subsequent decades, scientists found that tardigrades could withstand crushing pressure, deep freezes and even a trip to outer space.In 1963, a team of French researchers found that tardigrades could withstand massive blasts of X-rays. In more recent studies, researchers have found that some species of tardigrades can withstand a dose of radiation 1,400 times higher than what’s required to kill a person.A preflight photo of a marine tardigrade as seen magnified by 40 times under a light microscope.Boothby Lab/ReutersWe are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe. More

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    No ‘Hippie Ape’: Bonobos Are Often Aggressive, Study Finds

    Despite their peaceful reputation, bonobos act aggressively more often than their chimpanzee cousins, a new study found.In the early 1900s, primatologists noticed a group of apes in central Africa with a distinctly slender build; they called them “pygmy chimpanzees.” But as the years passed, it became clear that those animals, now known as bonobos, were profoundly different from chimpanzees.Chimpanzee societies are dominated by males that kill other males, raid the territory of neighboring troops and defend their own ground with border patrols. Male chimpanzees also attack females to coerce them into mating, and sometimes even kill infants. Among bonobos, in contrast, females are dominant. Males do not go on patrols, form alliances or kill other bonobos. And bonobos usually resolve their disputes with sex — lots of it.Bonobos became famous for showing that nature didn’t always have to be red in tooth and claw. “Bonobos are an icon for peace and love, the world’s ‘hippie chimps,’” Sally Coxe, a conservationist, said in 2006.But these sweeping claims were not based on much data. Because bonobos live in remote, swampy rainforests, it has been much more difficult to observe them in the wild than chimpanzees. More recent research has shown that bonobos live a more aggressive life than their reputation would suggest.In a study based on thousands of hours of observations in the wild published on Friday, for example, researchers found that male bonobos commit acts of aggression nearly three times as often as male chimpanzees do.“There is no ‘hippie ape,’” said Maud Mouginot, a biological anthropologist at Boston University who led the analysis.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe. More

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    PFAS ‘Forever Chemicals’ Are Pervasive in Water Worldwide, Study Finds

    A global survey found harmful levels even in water samples taken far any obvious source of contamination.They’re in makeup, dental floss and menstrual products. They’re in nonstick pans and takeout food wrappers. Same with rain jackets and firefighting equipment, as well as pesticides and artificial turf on sports fields.They’re PFAS: a class of man-made chemicals called per- and polyfluoroalkyl substances. They are also called “forever chemicals” because the bonds in their chemical compounds are so strong they don’t break down for hundreds to thousands of years, if at all.They’re also in our water.A new study of more than 45,000 water samples around the world found that about 31 percent of groundwater samples tested that weren’t near any obvious source of contamination have PFAS levels considered harmful to human health by the Environmental Protection Agency. About 16 percent of surface water samples tested, which were also not near any known source, have similarly hazardous PFAS levels.This finding “sets off alarm bells,” said Denis O’Carroll, a professor of civil and environmental engineering at the University of New South Wales and one of the authors of the study, which was published on Monday in Nature Geoscience. “Not just for PFAS, but also for all the other chemicals that we put out into the environment. We don’t necessarily know their long-term impacts to us or the ecosystem.”High levels of exposure to some PFAS chemicals have been linked to higher cholesterol, liver and immune system damage, hypertension and pre-eclampsia during pregnancy, as well as kidney and testicular cancer.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe. More

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    Large Scientific Review Confirms the Benefits of Physical Touch

    Premature babies especially benefited from skin-to-skin contact, and women tended to respond more strongly than men did.A hug, a handshake, a therapeutic massage. A newborn lying on a mother’s bare chest.Physical touch can buoy well-being and lessen pain, depression and anxiety, according to a large new analysis of published research released on Monday in the journal Nature Human Behaviour.Researchers from Germany and the Netherlands systematically reviewed years of research on touch, strokes, hugs and rubs. They also combined data from 137 studies, which included nearly 13,000 adults, children and infants. Each study compared individuals who had been physically touched in some way over the course of an experiment — or had touched an object like a fuzzy stuffed toy — to similar individuals who had not.For example, one study showed that daily 20-minute gentle massages for six weeks in older people with dementia decreased aggressiveness and reduced the levels of a stress marker in the blood. Another found that massages boosted the mood of breast cancer patients. One study even showed that healthy young adults who caressed a robotic baby seal were happier, and felt less pain from a mild heat stimulus, than those who read an article about an astronomer.Positive effects were particularly noticeable in premature babies, who “massively improve” with skin-to-skin contact, said Frédéric Michon, a researcher at the Netherlands Institute for Neuroscience and one of the study’s authors.“There have been a lot of claims that touch is good, touch is healthy, touch is something that we all need,” said Rebecca Boehme, a neuroscientist at Linkoping University in Sweden, who reviewed the study for the journal. “But actually, nobody had looked at it from this broad, bird’s eye perspective.”The analysis revealed some interesting and sometimes mysterious patterns. Among adults, sick people showed greater mental health benefits from touch than healthy people did. Who was doing the touching — a familiar person or a health care worker — didn’t matter. But the source of the touch did matter to newborns.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe. More

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    The Sunday Read: ‘What Deathbed Visions Teach Us About Living’

    Jack D’Isidoro and Anna Diamond and Sophia Lanman and Listen and follow The DailyApple Podcasts | SpotifyChris Kerr was 12 when he first observed a deathbed vision. His memory of that summer in 1974 is blurred, but not the sense of mystery he felt at the bedside of his dying father. Throughout Kerr’s childhood in Toronto, his father, a surgeon, was too busy to spend much time with his son, except for an annual fishing trip they took, just the two of them, to the Canadian wilderness. Gaunt and weakened by cancer at 42, his father reached for the buttons on Kerr’s shirt, fiddled with them and said something about getting ready to catch the plane to their cabin in the woods. “I knew intuitively, I knew wherever he was, must be a good place because we were going fishing,” Kerr told me.Kerr now calls what he witnessed an end-of-life vision. His father wasn’t delusional, he believes. His mind was taking him to a time and place where he and his son could be together, in the wilds of northern Canada.Kerr followed his father into medicine, and in the last 10 years he has hired a permanent research team that expanded studies on deathbed visions to include interviews with patients receiving hospice care at home and with their families, deepening researchers’ understanding of the variety and profundity of these visions.There are a lot of ways to listen to ‘The Daily.’ Here’s how.We want to hear from you. Tune in, and tell us what you think. Email us at thedaily@nytimes.com. Follow Michael Barbaro on X: @mikiebarb. And if you’re interested in advertising with The Daily, write to us at thedaily-ads@nytimes.com.Additional production for The Sunday Read was contributed by Isabella Anderson, Anna Diamond, Sarah Diamond, Elena Hecht, Emma Kehlbeck, Tanya Pérez and Krish Seenivasan. More

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    New England Journal of Medicine Ignored Nazi Atrocities, Historians Find

    The New England Journal of Medicine published an article condemning its own record during World War II.A new article in the New England Journal of Medicine, one of the oldest and most esteemed publications for medical research, criticizes the journal for paying only “superficial and idiosyncratic attention” to the atrocities perpetrated in the name of medical science by the Nazis.The journal was “an outlier in its sporadic coverage of the rise of Nazi Germany,” wrote the article’s authors, Allan Brandt and Joelle Abi-Rached, both medical historians at Harvard. Often, the journal simply ignored the Nazis’ medical depredations, such as the horrific experiments conducted on twins at Auschwitz, which were based largely on Adolf Hitler’s spurious “racial science.”In contrast, two other leading science journals — Science and the Journal of the American Medical Association — covered the Nazis’ discriminatory policies throughout Hitler’s tenure, the historians noted. The New England journal did not publish an article “explicitly damning” the Nazis’ medical atrocities until 1949, four years after World War II ended.The new article, published in this week’s issue of the journal, is part of a series started last year to address racism and other forms of prejudice in the medical establishment. Another recent article described the journal’s enthusiastic coverage of eugenics throughout the 1930s and ’40s.“Learning from our past mistakes can help us going forward,” said the journal’s editor, Dr. Eric Rubin, an infectious disease expert at Harvard. “What can we do to ensure that we don’t fall into the same sorts of objectionable ideas in the future?”In the publication’s archives, Dr. Abi-Rached discovered a paper endorsing Nazi medical practices: “Recent changes in German health insurance under the Hitler government,” a 1935 treatise written by Michael Davis, an influential figure in health care, and Gertrud Kroeger, a nurse from Germany. The article praised the Nazis’ emphasis on public health, which was infused with dubious ideas about Germans’ innate superiority.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe. More

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    Can Xerox’s PARC, a Silicon Valley Icon, Find New Life with SRI?

    Two research labs known for some of the tech industry’s most important innovations have merged in hopes of recapturing their glory days. It is one of Silicon Valley’s enduring legends. In 1979, a 24-year old Steve Jobs was permitted to visit Xerox’s Palo Alto Research Center (PARC) to view a demonstration of an experimental personal computer called the Alto. Mr. Jobs took away a handful of ideas that would transform the computing world when they became the heart of Apple’s Lisa and Macintosh computers. More

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    ‘Dune’-like Sandworm Existed Millions of Years Longer Than Thought

    Researchers examined fossils of the predatory worm and found a new species that persisted for 25 million years after it was believed to have become extinct.With a head covered in rows of curved spines, ancient Selkirkia worms could easily be confused with the razor-toothed sandworms that inhabit the deserts of Arrakis in “Dune: Part Two.”During the Cambrian Explosion more than 500 million years ago, these weird worms — which lived inside long, cone-shaped tubes — were some of the most common predators on the seafloor.“If you were a small invertebrate coming across them, it would have been your worst nightmare,” said Karma Nanglu, a paleontologist at Harvard. “It’s like being engulfed by a conveyor belt of fangs and teeth.”Thankfully for would-be spice harvesters, these ravenous worms disappeared hundreds of million years ago. But a trove of recently analyzed fossils from Morocco reveals that these formidable predators measuring only an inch or two in length, persisted much longer than previously thought.In a paper published today in the journal Biology Letters, Dr. Nanglu’s team described a new species of Selkirkia worm that lived 25 million years after this group of tube-dwellers was thought to have gone extinct.The newly described tubular worms were discovered when Dr. Nanglu and his colleagues sifted through fossils stored in the collection of Harvard’s Museum of Comparative Zoology. The fossils hail from Morocco’s Fezouata Formation, a deposit dating back to the Early Ordovician period, which began around 488 million years ago and spanned nearly 45 million years. This was a dynamic era when holdovers from the Cambrian rubbed shoulders with evolutionary newcomers like sea scorpions and horseshoe crabs.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe. More