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    How a Crisis for Vultures Led to a Human Disaster: Half a Million Deaths

    The birds were accidentally poisoned in India. New research on what happened next shows how wildlife collapse can be deadly for people.To say that vultures are underappreciated would be putting it mildly. With their diet of carrion and their featherless heads, the birds are often viewed with disgust. But they have long provided a critical cleaning service by devouring the dead.Now, economists have put an excruciating figure on just how vital they can be: The sudden near-disappearance of vultures in India about two decades ago led to more than half a million excess human deaths over five years, according to a forthcoming study in the American Economic Review.Rotting livestock carcasses, no longer picked to the bones by vultures, polluted waterways and fed an increase in feral dogs, which can carry rabies. It was “a really huge negative sanitation shock,” said Anant Sudarshan, one of the study’s authors and an economics professor at the University of Warwick in England.The findings reveal the unintended consequences that can occur from the collapse of wildlife, especially animals known as keystone species for the outsize roles they play in their ecosystems. Increasingly, economists are seeking to measure such impacts.A study looking at the United States, for example, has suggested that the loss of ash trees to the invasive emerald ash borer increased deaths related to cardiovascular and respiratory illness. And in Wisconsin, researchers found that the presence of wolves reduced vehicle collisions with deer by about a quarter, creating an economic benefit that was 63 times greater than the cost of wolves killing livestock.“Biodiversity and ecosystem functioning do matter to human beings,” said Eyal Frank, an economist at the University of Chicago and one of the authors of the new vulture study. “And it’s not always the charismatic and fuzzy species.”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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    A Blood Test Accurately Diagnosed Alzheimer’s 90% of the Time, Study Finds

    It was much more accurate than primary care doctors using cognitive tests and CT scans. The findings could speed the quest for an affordable and accessible way to diagnose patients with memory problems.Scientists have made another major stride toward the long-sought goal of diagnosing Alzheimer’s disease with a simple blood test. On Sunday, a team of researchers reported that a blood test was significantly more accurate than doctors’ interpretation of cognitive tests and CT scans in signaling the condition.The study, published Sunday in the journal JAMA, found that about 90 percent of the time the blood test correctly identified whether patients with memory problems had Alzheimer’s. Dementia specialists using standard methods that did not include expensive PET scans or invasive spinal taps were accurate 73 percent of the time, while primary care doctors using those methods got it right only 61 percent of the time.“Not too long ago measuring pathology in the brain of a living human was considered just impossible,” said Dr. Jason Karlawish, a co-director of the Penn Memory Center at the University of Pennsylvania who was not involved in the research. “This study adds to the revolution that has occurred in our ability to measure what’s going on in the brain of living humans.”The results, presented Sunday at the Alzheimer’s Association International Conference in Philadelphia, are the latest milestone in the search for affordable and accessible ways to diagnose Alzheimer’s, a disease that afflicts nearly seven million Americans and over 32 million people worldwide. Medical experts say the findings bring the field closer to a day when people might receive routine blood tests for cognitive impairment as part of primary care checkups, similar to the way they receive cholesterol tests.“Now, we screen people with mammograms and PSA or prostate exams and other things to look for very early signs of cancer,” said Dr. Adam Boxer, a neurologist at the University of California, San Francisco, who was not involved in the study. “And I think we’re going to be doing the same thing for Alzheimer’s disease and hopefully other forms of neurodegeneration.”In recent years, several blood tests have been developed for Alzheimer’s. They are currently used mostly to screen participants in clinical trials and by some specialists like Dr. Boxer to help pinpoint if a patient’s dementia is caused by Alzheimer’s or another condition.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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    Breast Cancer Survival Not Boosted by Double Mastectomy, Study Says

    A large study showed that for most patients, having both breasts removed after cancer was detected in one made no difference.For the more than 310,000 women diagnosed with breast cancer every year, no matter how well the treatment goes, there is always a lingering fear. Could the disease come back, even years later? And what if it comes back in the other breast? Could they protect themselves today by having a double mastectomy?A study has concluded that there is no survival advantage to having the other breast removed. Women who had a lumpectomy or a mastectomy and kept their other breast did just as well as women who had a double mastectomy, Dr. Steven Narod of Women’s College Hospital in Toronto and his colleagues reported, using U.S. data from more than 661,000 women with breast cancer on one side.In the study, published in JAMA Oncology on Thursday, the researchers added that most women did very well — the chance of cancer in the other breast was about 7 percent over 20 years.But the study’s results may not apply to women who have a gene variant, BRCA1 or BRCA2, which greatly increases their cancer risk. For the 1 in 500 American women with this variant, cancer researchers agree that it’s worth considering a double mastectomy.The finding that a double mastectomy is not protective against death for many breast cancers seems counterintuitive, Dr. Narod admitted. An accompanying editorial, by Dr. Seema Ahsan Khan, a breast cancer surgeon at Northwestern University, and Masha Kocherginsky, a biostatistician also at Northwestern, called it a conundrum.Previous smaller studies have come to the same conclusion. But, Dr. Narod said, some doctors have questioned the methods in earlier research. 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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    Fewer U.S. Adults Say They Will Have Children, Study Finds

    A new study breaks down the reasons more U.S. adults say they are unlikely to have children.When Jurnee McKay, 25, imagines having children, a series of scary scenarios pop into her mind: the “horrors” of childbirth, risks associated with pregnancy, a flighty potential partner, exorbitant child care costs.Abortion care restrictions are also on her list of fears. So Ms. McKay, a nursing student in Orlando, decided to eliminate the possibility of an accidental pregnancy. But the first doctor she consulted refused to remove her fallopian tubes, she said, insisting that she might change her mind after meeting her “soul mate.”“For some reason,” she said, “society looks at women who choose not to make life harder for themselves as crazy.”Next week, she will speak with another doctor about sterilization.Like Ms. McKay, a growing number of U.S. adults say they are unlikely to raise children, according to a study released on Thursday by the Pew Research Center. When the survey was conducted in 2023, 47 percent of those younger than 50 without children said they were unlikely ever to have children, an increase of 10 percentage points since 2018.When asked why kids were not in their future, 57 percent said they simply didn’t want to have them. Women were more likely to respond this way than men (64 percent vs. 50 percent). Further reasons included the desire to focus on other things, like their career or interests; concerns about the state of the world; worries about the costs involved in raising a child; concerns about the environment, including climate change; and not having found the right partner.The results echo a 2023 Pew study that found that only 26 percent of adults said having children was extremely or very important to live a fulfilling life. The U.S. fertility rate has been falling over the last decade, dipping to about 1.6 births per woman in 2023. This is the lowest number on record, according to the Centers for Disease Control and Prevention. And it is less than what would be required for the population to replace itself from one generation to the next.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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    Planet Sets Record for Hottest Day Twice in a Row

    Researchers with the European Union’s Copernicus Climate Change Service said Sunday was Earth’s hottest day. Then it happened again on Monday.Monday was most likely the hottest day ever recorded on Earth, with a global average of about 62.87 degrees Fahrenheit, or 17.15 degrees Celsius, preliminary data showed — beating a record that had been set just one day before.The data, released on Wednesday by the Copernicus Climate Change Service, a European Union institution that provides information about the past, present and future climate, caused alarm among some experts.Earlier this week, the service announced that Sunday had set a record, with a global average of about 62.76 degrees Fahrenheit, or 17.09 degrees Celsius. A day later it announced that Monday was the hottest day since at least 1940, when records began.Before this week’s back-to-back records, the previous record, 62.74 degrees Fahrenheit, or 17.08 degrees Celsius, was set last year, on July 6, besting a record that stood since 2016.Since Sunday’s and Monday’s temperatures were averages, some portions of the globe felt that extra heat more strongly, like parts of the Western United States where an excessive heat warning has been in place for days and is expected to continue for much of the week.“What is truly staggering is how large the difference is between the temperature of the last 13 months and the previous temperature records,” Carlo Buontempo, the director of the service, said in a news release announcing Sunday’s record. “We are now in truly uncharted territory and as the climate keeps warming, we are bound to see new records being broken in future months and years.”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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    Test Your Focus: Can You Spend 10 Minutes With One Painting?

    Our attention spans may be fried, but they don’t have to stay that way. In a modest attempt to sharpen your focus, we’d like you to consider looking at a single painting for 10 minutes, uninterrupted. Our exercise is based on an assignment that Jennifer Roberts, an art history professor at Harvard, gives to her […] More

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    Moving In Childhood Contributes to Depression, Study Finds

    A study of more than a million Danes found that frequent moves in childhood had a bigger effect than poverty on adult mental health risk.In recent decades, mental health providers began screening for “adverse childhood experiences” — generally defined as abuse, neglect, violence, family dissolution and poverty — as risk factors for later disorders.But what if other things are just as damaging?Researchers who conducted a large study of adults in Denmark, published on Wednesday in the journal JAMA Psychiatry, found something they had not expected: Adults who moved frequently in childhood have significantly more risk of suffering from depression than their counterparts who stayed put in a community.In fact, the risk of moving frequently in childhood was significantly greater than the risk of living in a poor neighborhood, said Clive Sabel, a professor at the University of Plymouth and the paper’s lead author.“Even if you came from the most income-deprived communities, not moving — being a ‘stayer’ — was protective for your health,” said Dr. Sabel, a geographer who studies the effect of environment on disease.“I’ll flip it around by saying, even if you come from a rich neighborhood, but you moved more than once, that your chances of depression were higher than if you hadn’t moved and come from the poorest quantile neighborhoods,” he added.The study, a collaboration by Aarhus University, the University of Manchester and the University of Plymouth, included all Danes born between 1982 and 2003, more than a million people. Of those, 35,098, or around 2.3 percent, received diagnoses of depression from a psychiatric hospital.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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    This Is Literally Your Brain on Drugs

    A small new study shows reactions in the brain in people who were given psilocybin in a controlled setting.If you had to come up with a groovy visualization of the human brain on psychedelic drugs, it might look something like this.Sara Moser/Washington University School of MedicineThe image, as it happens, comes from dozens of brain scans produced by researchers at Washington University School of Medicine in St. Louis who gave psilocybin, the compound in “magic mushrooms,” to participants in a study before sending them into a functional M.R.I. scanner.The kaleidoscopic whirl of colors they recorded is essentially a heat map of brain changes, with the red, orange and yellow hues reflecting a significant departure from normal activity patterns. The blues and greens reflect normal brain activity that occurs in the so-called functional networks, the neural communication pathways that connect different regions of the brain.The scans, published Wednesday in the journal Nature, offer a rare glimpse into the wild neural storm associated with mind-altering drugs. Researchers say they could provide a potential road map for understanding how psychedelic compounds like psilocybin, LSD and MDMA can lead to lasting relief from depression, anxiety and other mental health disorders.“Psilocybin, in contrast to any other drug we’ve tested, has this massive effect on the whole brain that was pretty unexpected,” said Dr. Nico Dosenbach, a professor of neurology at Washington University and a senior author of the study. “It was quite shocking when we saw the effect size.”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