Data Storage

Scientists Discover a New Kind of Magnet (ieee.org) 79

Wave723 shares a report from IEEE Spectrum: A new kind of magnet, theorized for decades, may now have been experimentally proven to exist. And it could eventually lead to better data storage devices. In a normal magnet, the magnetic moments of individual grains align with each other to generate a magnetic field. In contrast, in the new "singlet-based" magnet, magnetic moments are temporary in nature, popping in and out of existence. Although a singlet-based magnet's field is unstable, the fact that such magnets can more easily transition between magnetic and non-magnetic states can make them well-suited for data storage application. Specifically, they could operate more quickly and with less power than conventional devices, says Andrew Wray, a materials physicist at New York University who led the research. Now, Wray and his colleagues have discovered the first example of a singlet-based magnet that is robust -- one made from uranium antimonide (USb2). "It ends up taking very little energy to create spin excitons for uranium antimonide," Wray says. "This is essential for the singlet-based magnet, because if it took a lot of energy, then there wouldn't be enough spin excitons to condense, stabilize one another, and give you a magnet." The research has been published in the journal Nature Communications.
Mars

Mars Lander Seismometer Gets Protective Shield (theguardian.com) 24

Nasa's InSight Mars lander has placed a domed shield over its seismometer, completing that instrument's deployment. From a report: The seismometer will look for evidence of ongoing seismic activity on the red planet to provide data about the deep interior of Mars. This will help scientists determine how the planet formed. The seismometer, called the seismic experiment for interior structure (Seis), is the lander's highest priority science instrument. It is needed to complete about three-quarters of the mission's scientific objectives. The spacecraft touched down on 26 November 2018. On 19 December, a robotic arm picked up the instrument from its storage position and placed it on the martian surface about 1.6 metres away from the spacecraft.
Science

Feeding an Appetite-Suppressing Human Drug To Mosquitos Make Them Lose Their Attraction To Blood By Around 80%: Study (nature.com) 71

From Nature magazine: Female Aedes aegypti, like other mosquito species, feed on blood to get the protein they need to produce their eggs, and spread diseases such as dengue in the process. But once the mosquitoes have had their blood fix, they stop biting until they've laid their eggs several days later. Leslie Vosshall, a neurobiologist at the Rockefeller University in New York City, wondered whether she could hijack this biological process to switch off a mosquito's appetite.

Previous research had suggested that a mosquito's desire to feed is controlled by neuropeptides, molecules used by the nervous system to communicate. Vosshall and her team suspected that neuropeptide Y (NPY) receptors might be particularly important, because they form part of the molecular pathway involved in food-seeking behaviour for many animals -- including humans. Some human appetite-suppressant drugs already target the NPY receptors, so Vosshall decided to take a "completely zany" approach: feed these drugs to mosquitoes and see what happens. The method worked: mosquitoes that fed on a solution containing NPY-activating drugs were much less likely to approach a human-scented 'lure' than were the control group, and their appetites remained suppressed for two days.
Further reading: A New Way to Keep Mosquitoes From Biting.
Medicine

Scientists Are Working On Ways To Swap the Needle For a Pill (npr.org) 58

An anonymous reader quotes a report from NPR: One team of scientists, from MIT's Koch Institute for Integrative Cancer Research and Harvard's Brigham and Women's Hospital, developed a system to deliver insulin that actually still uses a needle -- but is so small you can swallow it and the injection doesn't hurt. They built a pea-size device containing a spring that ejects a tiny dart of solid insulin into the wall of the stomach, says gastroenterologist Carlo Giovanni Traverso, an associate physician at Brigham and Women's Hospital. "We chose the stomach as the site of delivery because we recognized that the stomach is a thick and robust part of the GI tract," Traverso says. Once the device gets into the stomach, the humidity there allows the spring to launch the insulin dart. As the researchers report in the journal Science, they've tested the device on pigs, and it can deliver a therapeutic dose of insulin provided the pig has an empty stomach.

On the other side of the U.S., nanoengineer Ronnie Fang of the University of California, San Diego and his colleagues have a different delivery system. Theirs is a kind of ingestible microrocket, about the size of a grain of sand, that is designed to zip past the stomach and into the small intestine. "It actually propels [itself] using bubbles in a reaction of magnesium with biological fluids," Fang says. The rocket has a coating that protects its payload from the acidic and enzyme-filled environment of the stomach. Once the rocket enters the small intestine, the change in acidity causes the coating to dissolve and lets the rocket stick to the intestinal wall to release its payload, in this case a vaccine protein. As Fang and his colleagues report in Nano Letters, their delivery system works in mice, but human testing is probably many years off.

Earth

A Hole Opens Up Under Antarctic Glacier -- Big Enough To Fit Two-Thirds of Manhattan (nbcnews.com) 281

Scientists have discovered an enormous void under an Antarctic glacier, sparking concern that the ice sheet is melting faster than anyone had realized -- and spotlighting the dire threat posed by rising seas to coastal cities around the world, including New York City and Miami. From a report: The cavity under Thwaites Glacier in West Antarctica is about six miles long and 1,000 feet deep -- representing the loss of 14 billion tons of ice. It was discovered after an analysis of data collected by Italian and German satellites, as well as NASA's Operation IceBridge, a program in which aircraft equipped with ice-penetrating radar fly over polar regions to study the terrain. The discovery is described in a paper published Jan. 30 in the journal Science Advances. The researchers expected to see significant loss of ice, but the scale of the void came as a shock.
Math

Bees Can Solve Math Problems With Addition and Subtraction 72

According to a new study published in the journal Science Advances, researchers from Australia and France have shown that bees can perform simple arithmetic, adding and subtracting small numbers by studying color-coded shapes. CNET reports: To test the buzzers' ability to perform arithmetic, the team used a three-chambered maze shaped like a Y, training bees to enter through a hole into a small chamber where they would see their first stimulus: blue or yellow shapes on a plain, grey background. The number of shapes varied between 1 and 5 and the color of the shapes told the bee whether it needed to add one (blue) or subtract one (yellow) from the initial number. The bee then flew into a subsequent chamber which presented both a correct option and an incorrect option. To train the bees, the correct option rewarded the critters with a drop of tasty sugar solution -- a delightful dessert for the bee. On the other hand, selecting the incorrect solution resulted in a nasty drop of quinine -- like a slab of Brussels sprouts slathered in chocolate.

The testing procedure itself focused on 14 bees undergoing four tests of 10 choices. The tests themselves were "non-reinforced," so they didn't receive reward or punishment when selecting their "answers" during testing. Because the bees were subjected to two answers each time, the expectation is that -- purely by chance -- they would select the correct answer 50 percent of the time. But the bees performed significantly better than chance would predict, selecting the correct answer around 65 percent of the time.
Earth

Global Warming Could Exceed 1.5C Within Five Years, Report Says (theguardian.com) 319

An anonymous reader quotes a report from The Guardian: Global warming could temporarily hit 1.5C above pre-industrial levels for the first time between now and 2023, according to a long-term forecast by the Met Office. Meteorologists said there was a 10% chance of a year in which the average temperature rise exceeds 1.5C, which is the lowest of the two Paris agreement targets set for the end of the century. Until now, the hottest year on record was 2016, when the planet warmed 1.11C above pre-industrial levels, but the long-term trend is upward. In the five-year forecast released on Wednesday, the Met Office highlights the first possibility of a natural El Niño combining with global warming to exceed the 1.5C mark. Climatologists stressed this did not mean the world had broken the Paris agreement 80 years ahead of schedule because international temperature targets are based on 30-year averages. Although it would be an outlier, scientists said the first appearance in their long-term forecasts of such a "temporary excursion" was worrying, particularly for regions that are usually hard hit by extreme weather related to El Nino. This includes western Australia, South America, south and west Africa, and the Indian monsoon belt.
News

Call for Retraction of 400 Scientific Papers On Organ Transplantation Amid Fears That Organs Came From Chinese Prisoners (theguardian.com) 141

A world-first study has called for the mass retraction of more than 400 scientific papers on organ transplantation, amid fears the organs were obtained unethically from Chinese prisoners. The Guardian reports: The Australian-led study exposes a mass failure of English language medical journals to comply with international ethical standards in place to ensure organ donors provide consent for transplantation. The study was published on Wednesday in the medical journal BMJ Open. Its author, the professor of clinical ethics Wendy Rogers, said journals, researchers and clinicians who used the research were complicit in "barbaric" methods of organ procurement.

"There's no real pressure from research leaders on China to be more transparent," Rogers, from Macquarie University in Sydney, said. "Everyone seems to say, 'It's not our job.' The world's silence on this barbaric issue must stop." A report published in 2016 found a large discrepancy between official transplant figures from the Chinese government and the number of transplants reported by hospitals. While the government says 10,000 transplants occur each year, hospital data shows between 60,000 to 100,000 organs are transplanted each year. The report provides evidence that this gap is being made up by executed prisoners of conscience.

Earth

2018 Was Earth's Fourth-Hottest Year on Record: NOAA and NASA Report (cnbc.com) 183

The string of hotter-than-average annual temperatures continued in 2018, as Earth experienced its fourth-hottest year on record, according to NASA and the National Oceanic and Atmospheric Administration [PDF]. From a report: Also in 2018, the United States suffered 14 weather and climate disasters with costs surpassing $1 billion during a warmer- and wetter-than-average year, NOAA reports. Global temperatures across land and sea were 1.42 degrees Fahrenheit above the 20th century average, making 2018 the fourth-warmest year since record-keeping began in 1880, NOAA said in a report Thursday. In a separate report, NASA's Goddard Institute for Space Studies said global temperatures were 1.5 degrees above the 1951 to 1980 mean, also the fourth highest going back to 1880.

The 2-degrees Fahrenheit increase in global temperatures since the late 19th century has been driven largely by growing carbon dioxide and other greenhouse gas emissions from human activity, said the institute's director, Gavin Schmidt. The conclusion reaffirms NASA's long-established finding that man-made emissions are driving climate change, which President Donald Trump and some senior administration officials frequently challenge. By both agencies' measures, Earth has now recorded its five hottest annual average temperatures in the past five years. "2018 is yet again an extremely warm year on top of a long-term global warming trend," Schmidt said in a press release.

Space

The Shape of the Milky Way Is Warped and Twisted (abc.net.au) 42

Necroloth writes: You probably thought that if you were looking at our galaxy from the outside and at a distance, you would see a thin disc of stars that orbit around a central region, but the further away from the inner regions of the Milky Way you are, the less the pull of gravity. At the outer disc, the hydrogen atoms that make up the Milky Way's gas disc are, as a consequence, warped into an S-like shape, no longer pulled together in a thin plane. A group of astronomers from Australia and China have built their "intuitive and accurate three-dimensional picture" by mapping 1339 classical Cepheids. There's a quick animation of the galaxy on the @NatureAstronomy twitter here. The study has been published in the journal Nature Astronomy.
Earth

As Magnetic North Pole Zooms Toward Siberia, Scientists Update World Magnetic Model (npr.org) 161

An anonymous reader quotes a report from NPR: Earth's geographic north pole is fixed. But the planet's magnetic north pole -- the north that your compass points toward -- wanders in the direction of Siberia at a rate of more than 34 miles per year. That movement may seem slow, but it has forced scientists to update their model of Earth's magnetic field a year earlier than expected so that navigational services, including map-based phone apps, continue to work accurately. The drift results from processes taking place at the center of the planet. Molten iron and nickel slosh and spin in the planet's core, essentially serving as a metallic conductor for Earth's magnetic field. Changes in that fluid flow lead to changes in the magnetic field. As a result of those changes, the accuracy of the National Oceanic and Atmospheric Administration's World Magnetic Model (WMM) -- a mathematical representation of the magnetic field -- slowly deteriorates in the five-year periods between updates. The next update was due in 2020. But "unplanned variations" have degraded the quality of the WMM so greatly that NOAA published an out-of-cycle update Monday. It was delayed from January by the partial government shutdown.
Science

New Technique Allows Scientists To Create Materials That Get Stronger With More Use (newatlas.com) 31

Scientists at Hokkaido University have found a way to create materials that actually get stronger the more you use them. "By mimicking the mechanism that allows living muscles to grow and strengthen after exercise, the team led by Jian Ping Gong developed a polymer that breaks down under mechanical stress, then regrows itself into a stronger configuration by feeding off a nutrient bath," reports New Atlas. From the report: To achieve this, the Hokkaido team used what is called double-network hydrogels. Like other hydrogels, these are polymers that are 85 percent water by weight, but in this case, the material consist of both a rigid, brittle polymer and a soft, stretchable one. In this way, the finished product is both soft and tough. However, the clever bit is that under laboratory conditions the hydrogel was immersed in a bath of monomers, which are the individual molecular links that make up a polymer. These serve the same function in the muscle-mimicking material as amino acids do in living tissue.

According to the team, when the hydrogel is stretched, some of the brittle polymer chains break, creating a chemical species called "mechanoradicals" at the end of the broken polymer chains. These are very reactive and quickly join up with the floating monomers to form a new, stronger polymer chain. Under testing, the hydrogel acted much like muscles under strength training. It became 1.5 times stronger, 23 times stiffer, and increased in weight by 86 percent. It was even possible to control the properties of the material by using heat-sensitive monomers and applying high temperatures to make it more water resistant. Gong says this approach could lead to materials suitable for a variety of applications, such as in flexible exosuits for patients with skeletal injuries that become stronger with use.
The study has been published in the journal Science. For those interested, the researchers have published a video discussing the new hydrogel material.
Science

Women's Brains Are 'Four Years Younger' Than Men's, Study Finds (theguardian.com) 125

Women's brains are nearly four years younger than men's, at least in how they burn fuel, according to scans performed by U.S. researchers. "Scientists found that healthy women have a 'metabolic brain age' that is persistently younger than men's of the same chronological age," reports The Guardian. "The difference is apparent from early adulthood and remains into old age." From the report: The finding suggests that changes in how the brain uses energy over a person's lifetime proceed more gradually in women than they do in men. While researchers are unsure of the medical consequences, it may help explain why women tend to stay mentally sharp for longer. "Brain metabolism changes with age but what we noticed is that a good deal of the variation we see is down to sex differences," said Marcus Raichle, a neurobiologist at Washington University school of medicine in St Louis. "If you look at how brain metabolism predicts a person's age, women come out looking about four years younger than they are."

The scientists used a brain scanning technique called positron emission tomography to measure the flow of oxygen and glucose in the brains of 121 women and 84 men aged 20 to 82. The scans revealed how sugar was being turned into energy in different parts of the volunteers' brains. To see how brain metabolism differed between the sexes, the researchers used a computer algorithm to predict people's ages based on brain metabolism as measured by the scans. First, the scientists taught it to predict men's ages from metabolism data gleaned from the male brain scans. The striking result came when the scientists fed metabolism data from the women into the same program. While the program estimated male ages accurately, it judged the women's brains to be, on average, 3.8 years younger than their real ages.
"The scientists then flipped the analysis around," the report adds. "They trained the algorithm to predict women's ages from data garnered from their brain scans. This time, when they fed metabolism data from the men into the computer, it estimated them to be 2.4 years older than they were. The way male brains burned sugar made them seem older than female ones of the same age." The study has been published in the journal Proceedings of the National Academy of Sciences.
Medicine

Colin Kroll, Founder of HQ Trivia and Vine, Died of Accidental Drug Overdose (nbcnewyork.com) 117

An anonymous reader quotes a report from NBC New York: Colin Kroll, the co-founder of HQ Trivia and Vine, died of an accidental overdose, the city's medical examiner announced Tuesday. According to the autopsy results, Kroll died of "acute intoxication due to the combined effects of fentanyl, fluoroisobutyryl fentanyl, heroin, and cocaine." Kroll, 34, was found dead in his SoHo, Manhattan, apartment on Dec. 16, 2018. Police responded to a 911 call for a welfare check at the Spring Street apartment where they found Kroll unconscious and unresponsive in a bedroom of the apartment, a New York Police Department spokesman previously told NBC News. Kroll was named the chief executive of HQ Trivia, a phone-based trivia platform, in September. Prior to that, Kroll co-founded Vine, the popular short-form video service acquired in 2012 by Twitter. Vine was discontinued four years later.
Mars

SpaceX Fires Mars-Bound Raptor Engine (extremetech.com) 105

Elon Musk took to Twitter Sunday evening to announce the "first firing of Starship Raptor flight engine." While SpaceX has fired individual components before and experimented with various designs, this is the first time the now-completed design has been assembled and fired in its intended spaceflight configuration. ExtremeTech reports: Raptor has gone through a number of design changes -- originally, SpaceX planned to mount it to the ITS launch vehicle back in 2016 (powered by 42 Raptor engines), before changing gears and unveiling its BFR rocket concept (officially known as "Super Heavy" for the first stage, and Starship for the second). The Super Heavy mounts 31 Raptor engines, while the Starship has seven. The engine has been designed with a priority on lowering overall wear and tear and removing failure points that could limit its reusability or increase long-term operating costs. Unlike SpaceX's Merlin engine, which runs on a mixture of RP-1 and LOX, the Raptor engine is fueled by cryogenic liquid methane and LOX. The Raptor uses subcooled methane (subcooling refers to keeping the temperature of the liquid well below its boiling point). Subcooling the methane allows SpaceX to increase the amount of propellant stored in the rocket. It increases specific impulse and reduces cavitation.

The actual test burn only goes on for a few seconds, but yields tremendously valuable information about the actual performance of the rocket and its ability to ignite in a controlled fashion. The green glow in the exhaust near the end of the firing indicates the copper liner in the engine chamber burned by accident. While this should not have happened, it's precisely to find these pain points that engineers conduct test firings in the first place. There is no substitute for this kind of test-firing and, as Ars Technica notes, "any 'first' test firing of a new, full-scale rocket engine that doesn't end in an uncontrolled explosion is a good thing." Ars also states that this specific engine may be deployed for "hopper" flights this year when SpaceX attempts to fly the Starship roughly 5km high, then land it again.

Earth

Rising Temperatures Could Melt Most Himalayan Glaciers By 2100 (nationalgeographic.com) 351

An anonymous reader quotes a report from The New York Times: Rising temperatures in the Himalayas, home to most of the world's tallest mountains, will melt at least one-third of the region's glaciers by the end of the century (Warning: source may be paywalled; alternative source) even if the world's most ambitious climate change targets are met, according to a report released Monday. If those goals are not achieved, and global warming and greenhouse gas emissions continue at their current rates, the Himalayas could lose two-thirds of its glaciers by 2100, according to the report, the Hindu Kush Himalaya Assessment. Under those more dire circumstances, the Himalayas could heat up by 8 degrees Fahrenheit (4.4 degrees Celsius) by century's end, bringing radical disruptions to food and water supplies, and mass population displacement. Glaciers in the Hindu Kush Himalayan Region, which spans over 2,000 miles of Asia, provide water resources to around a quarter of the world's population. One of the most complete studies on mountain warming, the Hindu Kush Himalaya Assessment was put together over five years by 210 authors. The report includes input from more than 350 researchers and policymakers from 22 countries.
Science

Frozen Train Tracks? Set 'Em on Fire (theatlantic.com) 116

It might look dangerous, but flames have kept switches moving and rails intact for a century. From a report: As if the horrors of the polar vortex were not already enough -- temperatures that look like typos, Canada Goose robbers, and something called frost quakes -- the nation's railroad system took a turn for the apocalyptic this week, too. Rails broke in three different places between Baltimore and Washington on Thursday, causing severe delays. Amtrak canceled dozens of trains passing through Chicago, and viral videos appeared to show commuter tracks in the city on fire. Of course, the tracks themselves were not burning -- they are made out of steel, prized for its tendency to rarely go up in flames. But the sight is still dramatic. The videos of the fires in Chicago last week show flames smoldering in patches of melted snow around the tracks.

Fires have been employed on railroads -- and remained the preferred fix for many a winter hazard -- for most of their roughly two-century history. While railroads have developed impressive tools for dealing with snow on the tracks, extreme temperatures remain a challenge. Though steel is flame-resistant, it's subject to cold, which can jam up railroads' many moving parts. When cold weather does wreak havoc on railroads, lighting fires on train tracks can serve a couple of uses. One is to thaw the switches that determine which track a train goes down, which is what Metra, the Chicagoland commuter-rail authority, said was going on this week. Switches are moving parts, and if ice gets into them, they can freeze in place. There are various types of switch heaters, which might use electric current or gas to melt ice -- or even an open gas flame, which is what's appearing in the Metra videos. Where there aren't switch heaters, crews might use temporary torchlike devices with a flame, the railroad equivalent of the smudge pots farmers use to keep citrus groves and apple orchards from freezing on cold nights.

Science

As the Chase For New Elements Slows, Scientists Focus on Deepening Their Understanding of the Superheavy Ones They Already Know (nature.com) 46

From a report: The quest to extend the periodic table is not over, but it is grinding to a halt. Since Russian chemist Dmitri Mendeleev published his periodic table 150 years ago, researchers have been adding elements to it at the average rate of one every two or three years. Having found all the elements that are stable enough to persist naturally, researchers started to create their own, and are now up to element 118, oganesson. Although they still hope to find more, they agree that prospects of venturing beyond element 120 are dim.

"We're reaching the area of diminishing returns in the synthesis of new elements, at least with our current level of technology," says Jacklyn Gates, who works on heavy-element chemistry at the Lawrence Berkeley National Laboratory in California. As a result, research on the edge of the periodic table is shifting focus. Rather than chasing new elements, scientists are going back to deepen their understanding of the superheavy ones -- roughly speaking, those with an atomic number above 100 -- that they have already made.

Studying the chemical properties of these elements could show whether the most massive ones obey the organizing principle of the table -- which sorts elements into groups with similar behaviours on the basis of periodically recurring patterns of chemical reactivity. And although the heaviest elements decay in less than the blink of an eye, researchers still hope that they might arrive at the fabled 'island of stability': a hypothesized region of element-land where some superheavy isotopes -- atoms that have the same number of protons in their nucleus, but differing numbers of neutrons -- might exist for minutes, days or even longer.

Mars

Well Water Likely Available Across Mars (behindtheblack.com) 102

schwit1 quotes Behind the Black: A science paper released today and available for download [pdf] cites evidence from about two dozen deep impact craters located from the equator to 37 degrees north latitude that Mars has a ground ice table at an elevation that also corresponds to other shoreline features.
The paper calls this evidence of "planet-wide groundwater" with elevations that "notably coincide with the elevation of some ocean shorelines proposed by previous authors."

Science writer Robert Zimmerman adds that "The evidence suggests that this deep groundwater water table (as ice) almost certainly still exists at all latitudes, though almost entirely underground...

"All you will have to do is dig a well..."
Space

Elon Musk Explains Why He's Building 'Starship' Out of Stainless Steel (popularmechanics.com) 308

Long-time Slashdot reader darkwing_bmf writes: In an exclusive interview with Popular Mechanics, SpaceX founder Elon Musk explains why stainless steel is the best material to build rocket ships, beating carbon fiber in cost, durability and even weight.
"As far as we know, this marks the first time the material has been used in spacecraft construction since some early, ill-fated attempts during the Atlas program in the late 1950s," reports Popular Mechanics.

"It took me quite a bit of effort to convince the team to go in this direction..." Musk tells them. But among the other benefits "It has a high melting point. Much higher than aluminum, and although carbon fiber doesn't melt, the resin gets destroyed at a certain temperature... But steel, you can do 1500, 1600 degrees Fahrenheit."

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