An anonymous reader quotes a report from Science Daily: Data from more than 17,000 teenagers show little evidence of a relationship between screen time and well-being in adolescents. The study, published in Psychological Science, a journal of the Association for Psychological Science, casts doubt on the widely accepted notion that spending time online, gaming, or watching TV, especially before bedtime, can damage young people's mental health. The research found that adolescents' total screen time per day had little impact on their mental health, both on weekends and weekdays. It also found that the use of digital screens 2 hours, 1 hour, or 30 minutes before bedtime didn't have clear associations with decreases in adolescent well-being, even though this is often taken as a fact by media reports and public debates.

Unlike other studies, the Oxford research analyzed data from Ireland, the US, and the UK to support its conclusions. The researchers used a rigorous methodology to gather how much time an adolescent spends on screens per day, including both self-reported measures and time-use diaries. This is important as many studies are based solely on self-reported digital technology use, even though recent work found only one third of participants give accurate accounts of how much time they spend online when asked after the fact. The researchers were also able to create a comprehensive picture of teens' well-being, examining measures of psychosocial functioning, depression symptoms, self-esteem, and mood, with data provided by both young people and their caregivers. Additionally, the final of the three studies conducted was preregistered, meaning that the researchers publicly documented the analyses they would run before they analyzed the data. This prevents hypothesizing after the results are known, a challenge for controversial research topics.

schwit1 shares a report from the New York Post: In the U.S., 5.8 million people are living with the debilitating condition, according to the Alzheimer's Association, and that number is projected to rise to nearly 14 million by 2050. Scientists at the Mayo Clinic in Minnesota believe, however, that many more people are probably already living with it without having a formal diagnosis. They've been using brain imaging to give a definite answer as to how many people are affected. Tests on 2,500 people have shown that double the number of people have telltale signs of protein plaques and tangles in the brain -- markers of Alzheimer's disease -- even if they're not experiencing dementia. "The prevalence of Alzheimer's disease is all based on clinical assessment. It's just based on the question 'Do you have dementia?'" Dr. Jack Clifford, the Alexander Family professor of Alzheimer's disease research at the Mayo Clinic, told The Telegraph. "Classically defined Alzheimer's undercounts people who have the pathology but do not have symptoms. A lot more people have the disease but do not have symptoms, just like a lot more people have hypertension than have had a stroke, or a lot more people have diabetes than people who have gone blind."

AmiMoJo shares a report from Gizmodo: Plenty of cat owners will happily tell you their felines are capable of responding to their own names, but the scientific jury remains ambivalent on the matter. A fascinating new experiment suggests this might actually be true for some cats, and it's a capacity very much tied to the social environment in which the cat lives. The new research, published today in Scientific Advances, doesn't mean cats understand the human conception of a name, but it does show that at least some cats can distinguish their names from other words. Prior research has shown that cats can recognize human gestures, facial expressions, and vocal cues. Slashdot reader sciencehabit adds: Give this a shot at home: Say four random words to your cat -- separated by about 15 seconds -- with the same length and intonation as its name. Then say its actual name. If it swivels its ears or perks up its head, chances are it knows what you call it. That's essentially what researchers did in a new study. The scientists saw similar responses when the cat's name came after the names of other felines he lived with, or when a stranger spoke the words. The findings are the first to experimentally show that cats have some understanding of what we are saying to them, the team concludes.

An anonymous reader quotes a report from CNN: Successive ocean heat waves are not only damaging Australia's Great Barrier Reef, they are compromising its ability to recover, raising the risk of "widespread ecological collapse," a new study has found. The 2,300-kilometer-long (1,500 mile) reef has endured multiple large-scale "bleaching" events caused by above-average water temperatures in the last two decades, including back-to-back occurrences in 2016 and 2017. The new study, released Wednesday in the journal Nature, examined the number of adult corals which survived these two events and how many new corals they created to replenish the reef in 2018.

The answer was as bleak as it was stark: "Dead corals don't make babies," the study's lead author, Terry Hughes, said in a press release. Scientists working on the study found the loss in adult corals caused a "crash in coral replenishment" on the reef, as heat stresses brought about by warming ocean temperatures impacted the ability of coral to heal. "The number of new corals settling on the Great Barrier Reef declined by 89% following the unprecedented loss of adult corals from global warming in 2016 and 2017," said Hughes. Scientists working on the report say they would expect coral recruitment to recover over the next 5 to 10 years, as more corals reach sexual maturity, but only in the absence of another bleaching event. However, with sea temperatures continuing to rise this seems a near-impossiblity.

Amazon is joining the race to provide broadband internet access around the globe via thousands of satellites in low Earth orbit, newly uncovered filings show. From a report: The effort, code-named Project Kuiper, follows up on last September's mysterious reports that Amazon was planning a "big, audacious space project" involving satellites and space-based systems. The Seattle-based company is likely to spend billions of dollars on the project, and could conceivably reap billions of dollars in revenue once the satellites go into commercial service. It'll take years to bring the big, audacious project to fruition, however, and Amazon could face fierce competition from SpaceX, OneWeb and other high-profile players.

Project Kuiper's first public step took the form of three sets of filings made with the International Telecommunications Union last month by the Federal Communications Commission on behalf of Washington, D.C.-based Kuiper Systems LLC. The ITU oversees global telecom satellite operations and eventually will have to sign off on Kuiper's constellation. The filings lay out a plan to put 3,236 satellites in low Earth orbit -- including 784 satellites at an altitude of 367 miles (590 kilometers); 1,296 satellites at a height of 379 miles (610 kilometers); and 1,156 satellites in 391-mile (630-kilometer) orbits. In response to GeekWire's inquiries, Amazon confirmed that Kuiper Systems is actually one of its projects.

SpaceX successfully ignited the onboard engine of its next-generation spacecraft, the Starship, for the first time today. "The ignition was a test known as a static fire, meant to try out the engine while the vehicle remained tethered to the Earth," reports The Verge. "However, today's test marked the first time this vehicle lit up its engine, and it could pave the way for short 'hop' flights in the near future." From the report: This particular vehicle, referred to as "Starhopper," is meant to test out the technologies and basic design of the final Starship vehicle -- a giant passenger spacecraft that SpaceX is making to take people to the Moon and Mars. The stainless steel Starship is supposed to launch into deep space on top of a massive booster called the Super Heavy, which will be capable of landing back on Earth after takeoff just like SpaceX's current Falcon 9 rocket fleet. And when complete, the Starship/Super Heavy combo should be capable of putting up to 220,000 pounds (100,000 kilograms) into low Earth orbit, according to SpaceX CEO Elon Musk, making it one of the most powerful rockets ever made.

SpaceX is currently building the first Starship spacecraft at the company's launch site and test facility in Texas, Musk said on Twitter. But before that vehicle sees space, SpaceX first plans to conduct a few hover flights with the Starhopper. These tests involve igniting the engine (or engines) attached to the bottom of the vehicle. Though these flights won't take the ship to space, they will test out SpaceX's new powerful Raptor engine -- a critical piece of hardware that will be used to power the future Starship and Super Heavy booster. SpaceX fired up a full-scale version of the Raptor engine for the first time in February. And for the last four months, SpaceX has been building the Starhopper at its Boca Chica facility, an area that the company plans to turn into a commercial launch site. Workers transported the vehicle to a test launchpad at the beginning of March and then recently attached a Raptor engine to its bottom.

By making programming more mathematical, a community of computer scientists is hoping to eliminate the coding bugs that can open doors to hackers, spill digital secrets and generally plague modern society. From a report: Now a set of computer scientists has taken a major step toward this goal with the release today of EverCrypt, a set of digital cryptography tools. The researchers were able to prove -- in the sense that you can prove the Pythagorean theorem -- that their approach to online security is completely invulnerable to the main types of hacking attacks that have felled other programs in the past. "When we say proof, we mean we prove that our code can't suffer these kinds of attacks," said Karthik Bhargavan, a computer scientist at Inria in Paris who worked on EverCrypt.

EverCrypt was not written the way most code is written. Ordinarily, a team of programmers creates software that they hope will satisfy certain objectives. Once they finish, they test the code. If it accomplishes the objectives without showing any unwanted behavior, the programmers conclude that the software does what it's supposed to do. Yet coding errors often manifest only in extreme "corner cases" -- a perfect storm of unlikely events that reveals a critical vulnerability. Many of the most damaging hacking attacks in recent years have exploited just such corner cases.

When India blew apart one of its satellites orbiting Earth last week, it created hundreds of pieces of orbital debris, and some of those pieces are large enough and high enough to pose a potential threat to the International Space Station, NASA says. "That is a terrible, terrible thing to create an event that sends debris in an apogee that goes above the International Space Station," NASA Administrator Jim Bridenstine said, referring to the debris' highest point in orbit. "And that kind of activity is not compatible with the future of human space flight that we need to see happen." NPR reports: In calculating the Indian test's potential impact last week, he said NASA determined that the risk of small debris hitting the space station was increased by 44 percent over a period of 10 days. "It's unacceptable, and NASA needs to be very clear about what its impact to us is," Bridenstine said, discussing space debris and India's anti-satellite test at a town hall event Monday.

As he spoke about the heightened risk, the NASA administrator also emphasized that both the space station and the astronauts aboard it are safe. The station can be maneuvered out of harm's way if needed, he added. But another danger, he said, is that "when one country does it, then other countries feel like they have to do it, as well." "The good thing is, it's low enough in Earth orbit that over time, this will all dissipate," Bridenstine said on Monday. Those pieces are expected to burn up as they re-enter Earth's atmosphere. India's intercept of its own satellite created 400 pieces of orbital debris, Bridenstine said. "What we are tracking right now -- objects big enough to track, we're talking about 10 centimeters [4 inches] or bigger -- about 60 pieces have been tracked," he said. "Of those 60, we know that 24 of them are going above the apogee of the International Space Station."

dryriver shares a report from the BBC: Tracking airplanes anywhere in the world just got a lot easier. The U.S. firm Aireon says its new satellite surveillance network is now fully live and being trialled over the North Atlantic. The system employs a constellation of 66 (Iridium) spacecraft, which monitor the situational messages pumped out by aircraft transponders. These report a plane's position, altitude, direction and speed every eight seconds. The two big navigation management companies that marshal plane movements across the North Atlantic -- UK Nats and Nav Canada -- intend to use Aireon to transform their operations. The more detailed information they now have about the behavior of airplanes means more efficient routing can be introduced. This ought to reduce costs for airlines. Passengers should also experience fewer delays. Aireon has receivers riding piggyback on all 66 spacecraft of the Iridium sat-phone service provider. These sensors make it possible now to track planes even out over the ocean, beyond the visibility of radar -- and ocean waters cover 70% of the globe. The rapid-fire nature of the messaging also means aircraft visibility is virtually continuous. Existing data links only report ocean-crossing aircraft positions every 14 minutes. '

An anonymous reader quotes a report from The Wall Street Journal: So far this year there have been 387 confirmed U.S. measles cases, more than 2018's full-year total and the second-largest number since the disease was declared eliminated in 2000 (Warning: source paywalled; alternative source), according to the Centers for Disease Control and Prevention. The disease has spread to 15 states in 2019, with six continuing outbreaks of three or more cases each in Washington, New York, New Jersey and California. The development has sparked new policies aimed at boosting inoculation and curbing misinformation about the measles vaccine.

Measles cases have has risen since 2000 as infected travelers bring the disease to the U.S. Those travelers -- unvaccinated foreign nationals or Americans who become infected abroad -- have spread the highly contagious disease to others in the U.S. who aren't vaccinated or hadn't previously had measles. These cases have fueled outbreaks in communities where large numbers of people haven't been inoculated because of personal or religious exemptions to the measles, mumps, and rubella (MMR) vaccine. The largest growth in infections since measles was eliminated totaled 23 outbreaks and 667 cases in 2014. Last year there were 17 outbreaks and 372 confirmed cases. The number of cases in 2019 could increase in the coming months. Measles is a seasonal disease, with cases rising in late winter and early spring in temperate climates, according to the World Health Organization.

According to a new study published in the journal Acta Tropica, listening to electronic music -- specifically dubstep, produced by U.S. artist Skrillex -- could protect against mosquito bites. The BBC reports: Sound is "crucial for reproduction, survival, and population maintenance of many animals," says a team of international scientists specializing in mosquitoes and the diseases they carry. They subjected adults of the species Aedes aegypti, known as the yellow fever mosquito, to electronic music to see whether it could work as a repellent. Scary Monsters And Nice Sprites, a track by Skrillex which features on his Grammy-award winning album of the same name, was chosen because of its mix of very high and very low frequencies.

"In insects, low-frequency vibrations facilitate sexual interactions, whereas noise disrupts the perception of signals from conspecifics [members of the same species] and hosts," the scientists said. Female adult mosquitoes were "entertained" by the track and attacked hosts later and less often than those in a dubstep-free environment. Scientists said "the occurrence of blood feeding activity was lower when music was being played." The scientists also found that mosquitoes exposed to the song had sex "far less often" than mosquitoes without music. "The observation that such music can delay host attack, reduce blood feeding, and disrupt mating provides new avenues for the development of music-based personal protective and control measures against Aedes-borne diseases."

An anonymous reader quotes a report from CBC.ca: Canada is, on average, experiencing warming at twice the rate of the rest of the world, with Northern Canada heating up at almost three times the global average, according to a new government report. Entitled "Canada's Changing Climate Report (CCCR)," the study was commissioned by the Environment and Climate Change Department and was slated to be released officially on Tuesday. That release date was moved up to Monday after CBC published its story about the leaked report.

The leaked copy of the report says that since 1948, Canada's annual average temperature over land has warmed 1.7 C, with higher rates seen in the North, the Prairies and northern British Columbia. In Northern Canada, the annual average temperature has increased by 2.3 C. According to the U.S. National Oceanic and Atmospheric Administration (NOAA), since 1948, global average temperatures have increased by about 0.8 C. Along with these temperature increases, the CCCR says Canada is experiencing increases in precipitation (particularly in winter), "extreme fire weather" and water supply shortages in summer, and a heightened risk of coastal flooding. The document says that while warming in Canada has been the result of both human activity and natural variations in the climate, "the human factor is dominant," especially emissions of greenhouse gases.

Burger King is testing a vegetarian version of its Whopper that uses an Impossible Burger for its patties, becoming the first national fast-food chain to sell the plant-based burger. From a report: The Restaurant Brands International subsidiary is offering the Impossible Whopper at 59 St. Louis locations. The chain already sells veggie patties made by Kellogg's vegetarian brand, Morningstar Farms. To announce the launch, Burger King released a video on April Fools' Day that shows unsuspecting Whopper fans eating the version with the Impossible Burger and then exclaiming that they can't taste the difference. Silicon Valley-based Impossible Foods genetically engineers heme, a protein that makes the vegetarian-friendly burger taste like meat. The ingredient is also responsible for giving the patty red juices that make it look like it's bleeding, just like a piece of beef.

"A second male birth control pill succeeded in preliminary testing, suggesting that a new form of contraception may eventually exist," reports Time: The new pill, which works similarly to female contraception, passed initial safety tests and produced hormone responses consistent with effective birth control in 30 men, according to research presented by the Los Angeles Biomedical Research Institute and the University of Washington at the Endocrine Society's annual meeting. (The study has not yet been published in a peer-reviewed journal.) It's early days for the drug -- which has not yet been submitted for approval by the Food and Drug Administration (FDA) -- but co-principal investigator Dr. Christina Wang, lead researcher at LA BioMed, says it's an important step toward effective, reversible male hormonal contraception....

Unlike a 2016 male birth control trial that famously stopped enrolling volunteers early because so many men complained of side effects, none of the men experienced serious problems, and no one stopped taking the drug because of side effects.

"It's like a time capsule of the end of the world," reports USA Today: 66 million years ago, in what's now North Dakota, a group of animals died together, only a few minutes after a huge asteroid smashed into the Earth near present-day Mexico. Scientists Friday announced the discovery of the jumbled, fossilized remains of the animals, all killed when a tsunami-like wave and a torrent of rocks, sand and glass buried them alive.

This graveyard of fish, mammals, insects and a dinosaur is a unique, first-of-its-kind discovery from the exact day that life on Earth changed forever, according to the study lead author Robert DePalma, a curator at the Palm Beach Museum of Natural History... DePalma added that the find provides spectacular new detail to what is perhaps the most important event to ever affect life on Earth... The asteroid impact and resulting mass extinction, which scientists call the K-T boundary, marked the end of the Cretaceous Era. The aftereffects of that infamous asteroid collision killed 75 percent of all species on Earth, including the dinosaurs. It's the planet's most recent mass extinction.
Scientists believe the asteroid was 12 kilometers (7.4 miles) wide, the BBC reports, and that it "hurled billions of tonnes of molten and vaporised rock into the sky in all directions - and across thousands of kilometres." DePalma argues that moment "is tied directly to all of us -- to every mammal on Earth, in fact. Because this is essentially where we inherited the planet.

"Nothing was the same after that impact. It became a planet of mammals rather than a planet of dinosaurs."

Reuters reports: India expects space debris from its anti-satellite weapons launch to burn out in less than 45 days, its top defense scientist said on Thursday, seeking to allay global concern about fragments hitting objects. The comments came a day after India said it used an indigenously developed ballistic missile interceptor to destroy one of its own satellites at a height of 300 km (186 miles), in a test aimed at boosting its defenses in space.

Critics say such technology, known to be possessed only by the United States, Russia and China, raises the prospect of an arms race in outer space, besides posing a hazard by creating a cloud of fragments that could persist for years. G. Satheesh Reddy, the chief of India's Defence Research and Development Organisation, said a low-altitude military satellite was picked for the test, to reduce the risk of debris left in space.
Space.com shared a reaction from a national security affairs professor at Naval War College in Newport, Rhode Island. They argued that India's test "likely represents a feeling by other countries, specifically India in this case, that the weaponization of space is forthcoming, and India doesn't want to be left out of the 'have' category if arms-control agreements are eventually reached."

sciencehabit shares an excerpt from Science Magazine: Talk about getting something for nothing. Physicists predict that just by shooting charged particles through an electromagnetic field, it should be possible to generate light from the empty vacuum. In principle, the effect could provide a new way to test the fundamental theory of electricity and magnetism, known as quantum electrodynamics, the most precise theory in all of science. In practice, spotting the effect would require lasers and particle accelerators far more powerful than any that exist now. Physicists have long known that energetic charged particles can radiate light when they zip through a transparent medium such as water or a gas. In the medium, light travels slower than it does in empty space, allowing a particle such as an electron or proton to potentially fly faster than light. When that happens, the particle generates an electromagnetic shockwave, just as a supersonic jet creates a shockwave in air. But whereas the jet's shockwave creates a sonic boom, the electromagnetic shockwave creates light called Cherenkov radiation. That effect causes the water in the cores of nuclear reactors to glow blue, and it's been used to make particle detectors.

However, it should be possible to ditch the material and produce Cherenkov light straight from the vacuum, predict Dino Jaroszynski, a physicist at the University of Strathclyde in Glasgow, U.K., and colleagues. The trick is to shoot the particles through an extremely intense electromagnetic field instead. According to quantum theory, the vacuum roils with particle-antiparticle pairs flitting in and out of existence too quickly to observe directly. The application of a strong electromagnetic field can polarize those pairs, however, pushing positive and negative particles in opposite directions. Passing photons then interact with the not-quite-there pairs so that the polarized vacuum acts a bit like a transparent medium in which light travels slightly slower than in an ordinary vacuum, Jaroszynski and colleagues calculate. Putting two and two together, an energetic charged particle passing through a sufficiently strong electromagnetic field should produce Cherenkov radiation, the team reports in a paper in press at Physical Review Letters. Others had suggested vacuum Cherenkov radiation should exist in certain situations, but the new work takes a more fundamental and all-encompassing approach, says Adam Noble, a physicist at Strathclyde.

An anonymous reader quotes a report from The Guardian: Doctors have identified a new mutation in a woman who is barely able to feel pain or stress after a surgeon who was baffled by her recovery from an operation referred her for genetic testing. Jo Cameron, 71, has a mutation in a previously unknown gene which scientists believe must play a major role in pain signaling, mood and memory. The discovery has boosted hopes of new treatments for chronic pain which affects millions of people globally.

In a case report published on Thursday in the British Journal of Anaesthesia, the UCL team describe how they delved into Cameron's DNA to see what makes her so unusual. They found two notable mutations. Together, they suppress pain and anxiety, while boosting happiness and, apparently, forgetfulness and wound healing. The first mutation the scientists spotted is common in the general population. It dampens down the activity of a gene called FAAH. The gene makes an enzyme that breaks down anandamide, a chemical in the body that is central to pain sensation, mood and memory. Anandamide works in a similar way to the active ingredients of cannabis. The less it is broken down, the more its analgesic and other effects are felt.

The second mutation was a missing chunk of DNA that mystified scientists at first. Further analysis showed that the "deletion" chopped the front off a nearby, previously unknown gene the scientists named FAAH-OUT. The researchers think this new gene works like a volume control on the FAAH gene. Disable it with a mutation like Cameron has and FAAH falls silent. The upshot is that anandamide, a natural cannabinoid, builds up in the system. Cameron has twice as much anandamide as those in the general population.

An anonymous reader shares a report: Academic and scientific research needs to be accessible to all. The world's most pressing problems like clean water or food security deserve to have as many people as possible solving their complexities. Yet our current academic research system has no interest in harnessing our collective intelligence. Scientific progress is currently thwarted by one thing: paywalls. Paywalls, which restrict access to content without a paid subscription, represent a common practice used by academic publishers to block access to scientific research for those who have not paid. This keeps $25.5bn flowing from higher education and science into for-profit publisher bank accounts.

My recent documentary, Paywall: The Business of Scholarship, uncovered that the largest academic publisher, Elsevier, regularly has a profit margin between 35-40%, which is greater than Google's. With financial capacity comes power, lobbyists, and the ability to manipulate markets for strategic advantages â" things that underfunded universities and libraries in poorer countries do not have. Furthermore, university librarians are regularly required to sign non-disclosure agreements on their contract-pricing specifics with the largest for-profit publishers. Each contract is tailored specifically to that university based upon a variety of factors: history, endowment, current enrolment. This thwarts any collective discussion around price structures, and gives publishers all the power.

An anonymous reader quotes a report from CNET: One of the central puzzles in particle physics is discovering what particle (or particles!) makes up dark matter — the form of matter that is responsible for 85 percent of the mass in the known universe. Some physicists believe searching for a hypothetical particle known as an "axion" could lead to a better understanding of dark matter and to hunt for it, a team of U.S. physicists have recently designed and tested a basketball-sized, donut-shaped apparatus that can seek it out.

It has been believed that axions may be detectable by looking at an unusual type of neutron star known as a "magnetar". These small, erupting stars create some of the most powerful magnetic fields in the universe. Because of their giant magnetic power, axions would be converted to radio waves in the presence of the magnetar -- and thus, detectable by telescopes on Earth. That strange cosmic phenomenon inspired theoretical physicists to create the impressively-named ABRACADABRA experiment (the full name is "A Broadband/Resonant Approach to Cosmic Axion Detection with an Amplifying B-field Ring Apparatus" so the theorists deserve a round of applause for that backcronym). The experiment consists of a donut (or "toroid") shaped device, dangled in a freezer just above absolute zero and fine-tuned to create its own magnetic field. If axions exist, the magnetic field in the middle of the donut could reveal them. The study has been published in the journal Physical Review Letters.