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Stories and comments across the archive that link to nature.com.
Stories · 1,757
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Physicists Measure Gravity With Record Precision (gizmodo.com)
An anonymous reader quotes a report from Gizmodo: A team of scientists in China are reporting that they have now performed the most precise measurement of gravity's strength yet by measuring G, the Newtonian or universal gravitational constant. G relates the gravitational attraction between two objects to their masses and the distance between them. The new measurement is important both for high-powered atomic clocks as well as the study of the universe, earth science, or any kind of science that relies on gravity in some way. The values measured by the team "have the smallest uncertainties reported until now," according to the paper published in Nature.
In the new study, scientists performed two independent calculations of G using a pair of pendulums in a vacuum, one pendulum setup for each test. Each pendulum swings back and forth between a pair of massive objects whose positions can be adjusted. The pendulums measure the force of gravity in two ways. First, they measure the difference between how quickly the pendulum swings to the "near," or parallel position, versus the "far," or horizontal position. They also measure how the direction of the pendulum's swing changes based on the pull of the test masses. The researchers ended up measuring 6.674184 and 6.674484 hundred billionths (10-11) for the time-of-swinging and angular acceleration methods, respectively. These measures were both very precise, but are still different from one another for unknown reasons. This might have had something to do with the string used for the pendulum. The paper's reviewer, Stephan Schlamminger from the National Institute of Standards and Technology, wrote in a commentary: "Li et al. carried out their experiments with great care and gave a detailed description of their work. The study is an example of excellent craftsmanship in precision measurements. However, the true value of G remains unclear. Various determinations of G that have been made over the past 40 years have a wide spread of values. Although some of the individual relative uncertainties are of the order of 10 parts per million, the difference between the smallest and largest values is about 500 parts per million." -
Physicists Measure Gravity With Record Precision (gizmodo.com)
An anonymous reader quotes a report from Gizmodo: A team of scientists in China are reporting that they have now performed the most precise measurement of gravity's strength yet by measuring G, the Newtonian or universal gravitational constant. G relates the gravitational attraction between two objects to their masses and the distance between them. The new measurement is important both for high-powered atomic clocks as well as the study of the universe, earth science, or any kind of science that relies on gravity in some way. The values measured by the team "have the smallest uncertainties reported until now," according to the paper published in Nature.
In the new study, scientists performed two independent calculations of G using a pair of pendulums in a vacuum, one pendulum setup for each test. Each pendulum swings back and forth between a pair of massive objects whose positions can be adjusted. The pendulums measure the force of gravity in two ways. First, they measure the difference between how quickly the pendulum swings to the "near," or parallel position, versus the "far," or horizontal position. They also measure how the direction of the pendulum's swing changes based on the pull of the test masses. The researchers ended up measuring 6.674184 and 6.674484 hundred billionths (10-11) for the time-of-swinging and angular acceleration methods, respectively. These measures were both very precise, but are still different from one another for unknown reasons. This might have had something to do with the string used for the pendulum. The paper's reviewer, Stephan Schlamminger from the National Institute of Standards and Technology, wrote in a commentary: "Li et al. carried out their experiments with great care and gave a detailed description of their work. The study is an example of excellent craftsmanship in precision measurements. However, the true value of G remains unclear. Various determinations of G that have been made over the past 40 years have a wide spread of values. Although some of the individual relative uncertainties are of the order of 10 parts per million, the difference between the smallest and largest values is about 500 parts per million." -
Climate Change Could Lead To Nutrient Deficiency For Hundreds of Millions (smithsonianmag.com)
An anonymous reader quotes a report from Smithsonian: According to new research, rising carbon dioxide levels will sap some of the nutrients from our crops and lead to dietary deficiencies in millions of humans. In 2014, field trials of common food crops including wheat, rice, corn and soybeans showed that as the amount of carbon dioxide in the atmosphere increased, the levels of iron, zinc and protein decreased in the dietary staples by 3 to 17 percent. While the decrease in a few nutrients may not seem important in food secure countries, it could have a big impact in poorer nations.
In the new study published in the journal Nature Climate Change, researchers calculated the impact of declining nutrients on human health. According to a press release, the team looked at the impact of rising CO2 on 225 different types of food. Based on population estimates for 2050 and an expected rise of carbon dioxide from about 400 parts per million today to 550 ppm by mid-century, the team found that the nutrient deficiencies of those already suffering will worsen, and 175 million more people could join the 1.2 billion who are zinc deficient and 122 million people would be added to the 622 million who don't receive enough protein. About 1.4 billion women of childbearing age and children under 5 could see their iron intake drop by about 4 percent. -
Climate Change Could Lead To Nutrient Deficiency For Hundreds of Millions (smithsonianmag.com)
An anonymous reader quotes a report from Smithsonian: According to new research, rising carbon dioxide levels will sap some of the nutrients from our crops and lead to dietary deficiencies in millions of humans. In 2014, field trials of common food crops including wheat, rice, corn and soybeans showed that as the amount of carbon dioxide in the atmosphere increased, the levels of iron, zinc and protein decreased in the dietary staples by 3 to 17 percent. While the decrease in a few nutrients may not seem important in food secure countries, it could have a big impact in poorer nations.
In the new study published in the journal Nature Climate Change, researchers calculated the impact of declining nutrients on human health. According to a press release, the team looked at the impact of rising CO2 on 225 different types of food. Based on population estimates for 2050 and an expected rise of carbon dioxide from about 400 parts per million today to 550 ppm by mid-century, the team found that the nutrient deficiencies of those already suffering will worsen, and 175 million more people could join the 1.2 billion who are zinc deficient and 122 million people would be added to the 622 million who don't receive enough protein. About 1.4 billion women of childbearing age and children under 5 could see their iron intake drop by about 4 percent. -
CERN's Pioneering Mini-Accelerator Passes First Test (nature.com)
An anonymous reader quotes a report from Nature: An experiment at CERN has demonstrated a new way of accelerating electrons to high energies -- one that could dramatically shrink the size of future particle accelerators and lower their costs. The technique is the latest entrant in a hot race to develop a technology called plasma wakefield acceleration. The method uses waves in plasma, a soup of ionized atoms, to push electrons to ever-higher energies over distances much shorter than those required in today's particle accelerators. Several laboratories have demonstrated plasma wakefield acceleration using two different approaches; most teams use laser beams to create the plasma waves needed. The latest work is the first to show that protons can also induce the waves and achieve electron acceleration -- a technique that may have advantages over the others because protons can carry high energies over long distances.
In this case, researchers diverted protons that would usually be fed into the Large Hadron Collider (LHC) at CERN, Europe's particle-physics lab near Geneva, Switzerland, and instead inserted them into the wakefield accelerator, called the Advanced Wakefield Experiment (AWAKE). The machine worked as expected and created a consistent beam of accelerated electrons. "That, for us, was a major achievement," says Matthew Wing, a physicist at University College London, who is deputy spokesperson for AWAKE. "It essentially says that the method works, and it's never been done before." The work is described in Nature on 29 August. -
CERN's Pioneering Mini-Accelerator Passes First Test (nature.com)
An anonymous reader quotes a report from Nature: An experiment at CERN has demonstrated a new way of accelerating electrons to high energies -- one that could dramatically shrink the size of future particle accelerators and lower their costs. The technique is the latest entrant in a hot race to develop a technology called plasma wakefield acceleration. The method uses waves in plasma, a soup of ionized atoms, to push electrons to ever-higher energies over distances much shorter than those required in today's particle accelerators. Several laboratories have demonstrated plasma wakefield acceleration using two different approaches; most teams use laser beams to create the plasma waves needed. The latest work is the first to show that protons can also induce the waves and achieve electron acceleration -- a technique that may have advantages over the others because protons can carry high energies over long distances.
In this case, researchers diverted protons that would usually be fed into the Large Hadron Collider (LHC) at CERN, Europe's particle-physics lab near Geneva, Switzerland, and instead inserted them into the wakefield accelerator, called the Advanced Wakefield Experiment (AWAKE). The machine worked as expected and created a consistent beam of accelerated electrons. "That, for us, was a major achievement," says Matthew Wing, a physicist at University College London, who is deputy spokesperson for AWAKE. "It essentially says that the method works, and it's never been done before." The work is described in Nature on 29 August. -
CERN's Pioneering Mini-Accelerator Passes First Test (nature.com)
An anonymous reader quotes a report from Nature: An experiment at CERN has demonstrated a new way of accelerating electrons to high energies -- one that could dramatically shrink the size of future particle accelerators and lower their costs. The technique is the latest entrant in a hot race to develop a technology called plasma wakefield acceleration. The method uses waves in plasma, a soup of ionized atoms, to push electrons to ever-higher energies over distances much shorter than those required in today's particle accelerators. Several laboratories have demonstrated plasma wakefield acceleration using two different approaches; most teams use laser beams to create the plasma waves needed. The latest work is the first to show that protons can also induce the waves and achieve electron acceleration -- a technique that may have advantages over the others because protons can carry high energies over long distances.
In this case, researchers diverted protons that would usually be fed into the Large Hadron Collider (LHC) at CERN, Europe's particle-physics lab near Geneva, Switzerland, and instead inserted them into the wakefield accelerator, called the Advanced Wakefield Experiment (AWAKE). The machine worked as expected and created a consistent beam of accelerated electrons. "That, for us, was a major achievement," says Matthew Wing, a physicist at University College London, who is deputy spokesperson for AWAKE. "It essentially says that the method works, and it's never been done before." The work is described in Nature on 29 August. -
Summer Weather Is Getting 'Stuck' Due To Arctic Warming (theguardian.com)
An anonymous reader quotes a report from The Guardian: Summer weather patterns are increasingly likely to stall in Europe, North America and parts of Asia, according to a new climate study that explains why Arctic warming is making heatwaves elsewhere more persistent and dangerous. Rising temperatures in the Arctic have slowed the circulation of the jet stream and other giant planetary winds, says the paper, which means high and low pressure fronts are getting stuck and weather is less able to moderate itself. The authors of the research, published in Nature Communications on Monday, warn this could lead to "very extreme extremes," which occur when abnormally high temperatures linger for an unusually prolonged period, turning sunny days into heat waves, tinder-dry conditions into wildfires, and rains into floods.
One cause is a weakening of the temperature gradient between the Arctic and Equator as a result of man-made greenhouse gas emissions. The far north of the Earth is warming two to four times faster than the global average, says the paper, which means there is a declining temperature gap with the central belt of the planet. As this ramp flattens, winds struggle to build up sufficient energy and speed to push around pressure systems in the area between them. As a result, there is less relief in the form of mild and wet air from the sea when temperatures accumulate on land, and less relief from the land when storms build up in the ocean. -
Climate Change Has Doubled the Frequency of Ocean Heatwaves (nature.com)
An anonymous reader quotes a report from Nature: Scientists analyzed satellite-based measurements of sea surface temperature from 1982 to 2016 and found that the frequency of marine heatwaves had doubled. These extreme heat events in the ocean's surface waters can last from days to months and can occur across thousands of kilometers. If average global temperatures increase to 3.5 degrees Celsius above pre-industrial levels by the end of the century, as researchers currently project, the frequency of ocean heatwaves could increase by a factor of 41. In other words, a one-in-one-hundred-day event at pre-industrial levels of warming could become a one-in-three-day event. The study has been published in the journal Nature. -
Climate Change Has Doubled the Frequency of Ocean Heatwaves (nature.com)
An anonymous reader quotes a report from Nature: Scientists analyzed satellite-based measurements of sea surface temperature from 1982 to 2016 and found that the frequency of marine heatwaves had doubled. These extreme heat events in the ocean's surface waters can last from days to months and can occur across thousands of kilometers. If average global temperatures increase to 3.5 degrees Celsius above pre-industrial levels by the end of the century, as researchers currently project, the frequency of ocean heatwaves could increase by a factor of 41. In other words, a one-in-one-hundred-day event at pre-industrial levels of warming could become a one-in-three-day event. The study has been published in the journal Nature. -
Study Finds Flaw In Emergent Gravity (phys.org)
An anonymous reader quotes a report from Phys.Org: In recent years, some physicists have been investigating the possibility that gravity is not actually a fundamental force, but rather an emergent phenomenon that arises from the collective motion of small bits of information encoded on spacetime surfaces called holographic screens. The theory, called emergent gravity, hinges on the existence of a close connection between gravity and thermodynamics. Emergent gravity has received its share of criticism, however, and a new paper adds to this by showing that the holographic screen surfaces described by the theory do not actually behave thermodynamically, undermining a key assumption of the theory.
In the new paper, the scientists tested whether different kinds of surfaces obey an analogue of the first law of thermodynamics, which is a special form of energy conservation. Their results reveal that, while surfaces near black holes (called stretched horizons) do obey the first law, ordinary surfaces -- including holographic screens -- generally do not. The only exception is that ordinary surfaces that are spherically symmetric do obey the first law. As the scientists explain, the finding that stretched horizons obey the first law is not surprising, since these surfaces inherit much of their behavior from the nearby horizons. Still, the scientists caution that the results do not necessarily imply that stretched horizons obey all of the laws of thermodynamics. On the other hand, the finding that ordinary surfaces do not obey the first law is more unexpected, especially as it is one of the key assumptions of emergent gravity. Going forward, researchers will work to understand what this means for the future of emergent gravity, as well as explore other possible implications. -
Chemists Discover How Blue Light Speeds Blindness
Isao writes: It (apparently) has been known that blue light damages eyes and accelerates macular degeneration. A new article on Phys.org may have identified how this happens. It seems that unlike other light colors, blue causes a necessary molecule (retinal) to permanently kill photoreceptor cells. "The researcher found that a molecule called alpha Tocopherol, a Vitamin E derivative and a natural antioxidant in the eye and body, stops the cells from dying," reports Phys.org. "However, as a person ages or the immune system is suppressed, people lose the ability to fight against the attack by retinal and blue light." The authors will continue their research and recommend filtering and blue-light reduction in the meantime. The study has been published in the journal Scientific Reports. -
US Scientist Who Edited Human Embryos With CRISPR Responds To Critics (technologyreview.com)
Facing criticism from fellow scientists, the researcher behind the world's largest effort to edit human embryos with CRISPR is vowing to continue his efforts to develop what he calls "IVF gene therapy." MIT Technology Review: Shoukhrat Mitalipov, of Oregon Health Sciences University in Portland, drew global headlines last August when he reported successfully repairing a genetic mutation in dozens of human embryos, which were later destroyed as part of the experiment. The laboratory findings on early-stage embryos, he said, had brought the eventual birth of the first genetically modified humans "much closer" to reality. The breakthrough drew wide attention, including from critics who quickly pounced, calling it biologically implausible and potentially the result of careless errors and artifacts. Today, those critics are getting an unusual hearing in the journal Nature, which is publishing two critiques of the Oregon research as well as a lengthy reply from Mitalipov and 31 of his coworkers in South Korea, China, and the Salk Institute in La Jolla, California. The scientific sparring centers on CRISPR's well-known tendency to introduce unseen damage into a cell's DNA.
[...] Mitalipov remains intent on proving that CRISPR can work safely on embryos. In an interview, Mitalipov said he believes it will take five to 10 years before the process is ready to attempt in an IVF center. The revolutionary medical technology being pursued is a way to adjust an embryo's DNA to remove disease risks. It is sometimes called germline gene editing because any DNA fixes a baby is born with would then be passed down to future generations through that person's germ cells, the egg or sperm. For its initial research, the Oregon team recruited women around Portland and paid them $5,000 each to undergo an egg retrieval. With those eggs the team created more than 160 embryos for CRISPR experiments. Mitalipov said his Oregon center continues to obtain eggs in an ongoing effort to confirm his results and extend them in new directions. -
Plan To Replicate 50 High-Impact Cancer Papers Shrinks To Just 18 (sciencemag.org)
Five years ago, researchers set out to replicate experiments from 50 high-impact cancer biology papers. Now, due to various challenges relating to a lack of funding and expertise, the project only expects to complete just 18 studies. Science Magazine reports: The Reproducibility Project: Cancer Biology (RP:CP) began in October 2013 as an open effort to test replicability after two drug companies reported they had trouble reproducing many cancer studies. The work was a collaboration with Science Exchange, a company based in Palo Alto, California, that found contract labs to reproduce a few key experiments from each paper. Funding included a $1.3 million grant from the Laura and John Arnold Foundation, enough for about $25,000 per study. Experiments were expected to take 1 year.
Costs rose and delays ensued as organizers realized they needed more information and materials from the original authors; a decision to have the proposed replications peer reviewed also added time. Organizers whittled the list of papers to 37 in late 2015, then to 29 by January 2017. In the past few months, they decided to discontinue 38% or 11 of the ongoing replications, Errington says. (Elizabeth Iorns, president of Science Exchange, says total costs for the 18 completed studies averaged about $60,000, including two high-priced "outliers.") One reason for cutting off some replications was that it was taking too long to troubleshoot or optimize experiments to get meaningful results... So far, the project has published replication results for 10 of the 18 studies. "Five were mostly repeatable, three were inconclusive, and two studies were negative, but the original findings have been confirmed by other labs," reports Science Magazine. "In fact, many of the initial 50 papers have been confirmed by other groups, as some of the RP:CB's critics have pointed out." -
New Anti-Cancer Drug Put Cancers To Sleep In Mice -- Permanently (medicalxpress.com)
"Australian scientists have taken a 'major step forward' in the world of cancer research," reports ABC (the national broadcaster of Australia). Long-time Slashdot reader Artem Tashkinov quotes an announcement from the Walter and Eliza Hall Institute of Medical Research: In a world first, Melbourne scientists have discovered a new type of anti-cancer drug that can put cancer cells into a permanent sleep, without the harmful side-effects caused by conventional cancer therapies.
Published today in the journal Nature, the research reveals the first class of anti-cancer drugs that work by putting the cancer cell to sleep -- arresting tumour growth and spread without damaging the cells' DNA.
The new class of drugs could provide an exciting alternative for people with cancer, and has already shown great promise in halting cancer progression in models of blood and liver cancers, as well as in delaying cancer relapse.
One of the lead researchers says the new compounds "had already shown great promise in preclinical testing." -
Scientists Stunned as Medical Non-Profit Group Abruptly Ends Research Grants (nature.com)
A major US non-profit group focused on improving child health has abruptly terminated US$3 million in research grants -- leaving nearly 40 scientists confused, angry and scrambling to secure new funding. From a report: On 24 July, 37 grant recipients received an e-mail from the March of Dimes Foundation in New York City informing them that their 3-year grants had been cut off, retroactively, starting on 30 June. Many of the researchers were only a year into their projects, and had had just enough time to hire and train staff, purchase supplies and generate preliminary results. Now, several say that they might need to lay off employees, euthanize lab animals and shelve their research projects if they cannot find other funding -- fast. The March of Dimes, which is supported largely by individual donations, made the decision to revoke the grants because of a budget shortfall, says Kelle Moley, the group's chief scientific officer. "I know this is harsh news," Moley says. "As a former grantee, this would be devastating to me as well." That is small consolation to many researchers whom Nature spoke to. -
Rare Blue Diamonds Lurk Deep In Earth's Core (washingtonpost.com)
Scientist believe they now know how extremely rare blue diamonds are formed. After studying 46 of the gems, they found that blue diamonds are formed as deep as the transition zone between the planet's upper and lower mantle (Warning: source may be paywalled; alternative source) -- far greater depths than other diamonds, some deeper than 410 miles. The Washington Post reports: Just 1 out of 200,000 diamonds are blue. Like all diamonds, they are made when carbon comes under intense pressure and extreme heat deep inside the Earth. As they form, they can trap tiny bits of rock inside -- like fossils in amber. "Diamond is an extraordinary container, a time capsule," said Steven Shirey, a geochemist at the Carnegie Institution for Science in Washington. Shirey and his colleagues used lasers to examine the diamonds' imperfections -- slivers of embedded rock -- at the Gemological Institute of America. The researchers suggest that boron in the ocean floor was pushed down when plates that make up the Earth's crust collided. The element allows the stone to absorb some red light, so the diamond looks blue. The findings were published in the journal Nature. -
Terraforming Might Not Work on Mars, New Research Says (discovermagazine.com)
Mars might not have the right ingredients to terraform into our planetary home away from home -- even with the recent discovery of liquid water buried near its south pole. From a report: Research published Monday in Nature Astronomy puts a kibosh on the idea of terraforming Mars. At the heart of the study is carbon dioxide. Carbon dioxide, a greenhouse gas, is abundant on Mars -- its thin atmosphere is made of the stuff, and the white stuff we often see on the surface is dry ice, not snow. CO2 is even trapped in the rocks and soil. That abundance has long fueled visions of a fantasy future where all that trapped carbon dioxide is released, creating a thicker atmosphere that warms the planet. SpaceX founder Elon Musk has even proposed nuking Mars to make this happen.
But in this new study, veteran Mars expert Bruce Jakosky of the University of Colorado Boulder and Christopher S. Edwards of Northern Arizona University, surveyed how much carbon dioxide is available for terraforming the Red Planet. They combined Martian CO2 observations from various missions -- NASA's MAVEN atmospheric probe, the European Space Agency's Mars Express orbiter, as well as NASA's Odyssey and the Mars Reconnaissance Orbiter. The results throw shade on the dreams of futurists. -
A New Shape Called the 'Scutoid' Has Been Discovered In Our Cells (gizmodo.com)
Scientists have discovered a new shape called the scutoid (SCOO-toid) while studying epithelial cells, the building blocks of embryos that eventually end up forming our skin and lining our organs and blood vessels. The new "twisted prism" shape is "extremely efficient at keeping cells tightly-packed and organized in the literal twists and turns of development," reports Gizmodo. From the report: As embryos grow, their tissues curve and bend as they start to form into organs. Scientists thought the cells could stay tightly packed if they were bottle- or column-shaped, but computer modeling suggested that a more complex shape would be more likely. First, a computer model set out to predict which cell shapes would be most efficient at staying in contact with one another in both flat or curved layers. That shape ended up being prism-like, with six sides one end, five on the other, and a strange triangular face on one of the long edges of the prism. Using microscopy and computer imaging, the team confirmed that cells found in fruit fly salivary glands and cells in zebrafish were indeed scutoid-shaped. As noted in their paper published Friday in Nature Communications, the researchers believe these scutoid-shaped cells exist in any curved sheet of epithelial cells -- even in humans. -
Scientists Perfect Technique To Create Most Dense, Solid-State Memory in History that Could Soon Exceed the Capabilities of Current Hard Drives By 1,000 Times (newatlas.com)
New submitter weedjams shares a report: Scientists at the University of Alberta have demonstrated a new data storage technique that stores zeroes and ones by the presence (or absence) of individual hydrogen atoms. The resulting storage density is an unparalleled 1.2 petabits per square inch -- 1,000 times greater than current hard disk and solid state drives, and 100 times greater than Blu-rays. The researchers, led by PhD student Roshan Achal and physics professor Robert Wolkow, built on a technique previously developed by Walkow that used the tip of a scanning tunneling microscope (STM) to remove or replace individual hydrogen atoms resting on a silicon substrate.
The inconceivably small dimensions (a hydrogen atom is only half a nanometer in diameter) allow for an astounding data storage density of 1.1 petabits (138 terabytes) per square inch. By comparison, a Blu-ray disk can "only" store about 12 terabits of data in the same area (one hundredth the data density), while both traditional magnetic hard drives and solid-state drives store somewhere in the region of 1.5 terabits per square inch (a thousandth of the density). This development, says Achal, could allow you to store the entire iTunes library of 45 million songs on the surface of a US quarter-dollar coin.
Achal and his team demoed the technology by creating a 192-bit cell, which they used to store a simple rendition of the Super Mario Bros video game theme song. To show the rewrite capabilities, the scientists also created an 8-bit memory cell which they used to store the letters of the alphabet one by one, represented via their respective ASCII code. Further reading: ScienceDaily, and Nature. -
Software Beats Animal Tests at Predicting Toxicity of Chemicals (nature.com)
Machine-learning software trained on masses of chemical-safety data is so good at predicting some kinds of toxicity that it now rivals -- and sometimes outperforms -- expensive animal studies, researchers report. From a report: Computer models could replace some standard safety studies conducted on millions of animals each year, such as dropping compounds into rabbits' eyes to check if they are irritants, or feeding chemicals to rats to work out lethal doses, says Thomas Hartung, a toxicologist at Johns Hopkins University in Baltimore, Maryland. "The power of big data means we can produce a tool more predictive than many animal tests."
In a paper published in Toxicological Sciences on 11 July, Hartung's team reports that its algorithm can accurately predict toxicity for tens of thousands of chemicals -- a range much broader than other published models achieve -- across nine kinds of test, from inhalation damage to harm to aquatic ecosystems. The paper "draws attention to the new possibilities of big data," says Bennard van Ravenzwaay, a toxicologist at the chemicals firm BASF in Ludwigshafen, Germany. "I am 100% convinced this will be a pillar of toxicology in the future." Still, it could be many years before government regulators accept computer results in place of animal studies, he adds. And animal tests are harder to replace when it comes to assessing more complex harms, such as whether a chemical will cause cancer or interfere with fertility." -
Nitrogen Is In Liquid Metal Form Inside Earth's Core (eurekalert.org)
hackingbear writes: A team of scientists from China, the U.S., and U.K. successfully turned nitrogen, the dominant gas in Earth's atmosphere, into a metallic fluid by subjecting it to the extreme pressure and temperature conditions found deep inside the Earth and other planets. Their findings have been published in the journal Nature Communications .
"Our findings could inform the efforts to create forms of energetic nitrogen polymers as well as superconducting, metallic states of a sister diatomic molecule, hydrogen or H2, which could revolutionize the energy sector if reliably synthesized," according to team member Nicholas Holtgrewe. The project was funded by by the (U.S.) National Science Foundation, the (U.S.) Army Research Office, the National Natural Science Foundation of China, the Chinese Academy of Science, the British Council Researcher Links Program, and other sources. According to EurekAlert, "The researchers found that the temperature at which nitrogen transitions from insulating to metallic decreases as the pressure increases -- starting at about 1,180,000 times normal atmospheric pressure (120 gigapascals) and 2,720 degrees Celsius (3,000 kelvin)." "This means that, theoretically, nitrogen would remain in its diatomic state in the Earth's mantle but would disassociate into a fluid metal in or just above the core, which potentially has implications for our understanding of the planet's deep nitrogen cycle," said team member Sergey Lobanov. -
Scientists Use Caffeine To Control Genes (arstechnica.com)
An anonymous reader quotes a report from Ars Technica: A team led by Martin Fussenegger of ETH Zurich in Basel has shown that caffeine can be used as a trigger for synthetic genetic circuitry, which can then in turn do useful things for us -- even correct or treat medical conditions. For a buzz-worthy proof of concept, the team engineered a system to treat type 2 diabetes in mice with sips of coffee, specifically Nespresso Volluto coffee. Essentially, when the animals drink the coffee (or any other caffeinated beverage), a synthetic genetic system in cells implanted in their abdomens switches on. This leads to the production of a hormone that increases insulin production and lowers blood sugar levels -- thus successfully treating their diabetes after a simple morning brew.
The system, published Tuesday in Nature Communications, is just the start, Fussenegger and his colleagues suggest enthusiastically. "We think caffeine is a promising candidate in the quest for the most suitable inducer of gene expression," they write. They note that synthetic biologists like themselves have long been in pursuit of such inducers that can jolt artificial genetics. But earlier options had problems. These included antibiotics that can spur drug-resistance in bacteria and food additives that can have side effects. Caffeine, on the other hand, is non-toxic, cheap to produce, and only present in specific beverages, such as coffee and tea, they write. It's also wildly popular, with more than two billion cups of coffee poured each day worldwide. -
Study Suggests There's No Limit On Longevity (smithsonianmag.com)
An anonymous reader quotes a report from Smithsonian: The science of longevity is surprisingly controversial, mainly because there are so few people of extreme old age -- defined at 110 years or older -- around to study. So researchers look to statistics to try and figure out how long people can live. [Ben Guarino reports via The Washington Post] that in 1825, actuary Benjamin Gompertz put forth the idea that the odds of dying grow exponentially as we age. Further research bears that out. Between the age of 30 and 80, the odds of dying double every 8 years. What happens after that, however, is not completely figured out. According to a controversial study released in 2016, which analyzed data from 40 different countries, the average person could make it to 115 with the right genes and interventions, and a few genetic superstars would be able to make it to 125. But that was it, they argued. There was a wall of mortality that medicine and positive thinking simply cannot overcome.
But not everyone is convinced by that data. That's why for the new paper in the journal Science, researchers looked at the lifespans of 3,836 people in Italy who reached the age of 105 or older between 2009 and 2015, with their ages verified by birth certificates. What they found is that the Gompertz law goes a little haywire around the century mark. According to a press release, a 90 year old woman has a 15 percent chance of dying in the next year, and an estimated six years left to live. At age 95, the chance of dying per year jumps to 24 percent. At the age of 105, the chance of dying makes another leap to 50 percent. But then, surprisingly, it levels off, even past 110. In other words, at least statistically, each year some lucky person could flip the coin of life, and if it comes up heads every time, they could live beyond 115 or 125. -
Ocean Spray On Saturn Moon Contains Crucial Constituents For Life (theguardian.com)
Astronomers have found that blasts of ocean spray erupting from the Saturn moon of Enceladus contain complex organic molecules, "making it the only place beyond Earth known to harbor crucial constituents for life as we know it," reports The Guardian. From the report: Astronomers detected the compounds in plumes of water and ice that shoot from huge fractures in the south pole of Enceladus, a 300-mile-wide ice ball that orbits Saturn along with 52 other moons. Enceladus stands out among the planet's natural satellites because it hosts a global water ocean beneath its frozen crust. German and U.S. scientists found tell-tale signs of organic molecules far more complex than amino acids and 10 times heavier than methane in data gathered by Nasa's Cassini probe as it flew over the fractures on Enceladus. Known as "tiger stripes," the fissures reach several miles down into the ice and are largely filled with ocean water that percolates up from the ocean.
Writing in the journal Nature, Frank Postberg, a planetary scientist who worked on the data at Heidelberg University, and his colleagues describe their analysis of fresh Cassini data that shows that most ice particles blasting out of Enceladus are almost pure water. But a small proportion, about 1%, are rich in organic molecules containing carbon, hydrogen, oxygen and potentially nitrogen too. Some were made up of hundreds of atoms. "Our results mark the first ever detection of complex organics coming from an extraterrestrial water world," said Postberg. -
Can Two Injections of Tuberculosis Vaccine Cure Diabetes? (fortune.com)
An anonymous reader quotes Fortune: The causes of Type 1 diabetes can be significantly reversed over several years with just two injections of a common tuberculosis vaccine injected a few weeks apart, researchers at Massachusetts General Hospital announced Thursday in a paper published in the journal Nature. Researchers found a substantial reduction in the blood-sugar marker HbA1c that is used to diagnose diabetes.
All subjects with diabetes who received the vaccine had a 10% reduction after three years and 18% after four years, bringing them below the cutoff point for a clinical diagnosis. Those subjects followed for a full eight years retained most of the reduction. Participants who received a placebo or were in a reference group that followed normal diabetic management saw their blood sugar measurement rise by a few percentage points during the same periods followed... A 10% reduction in Hb1Ac reduces the risk of death as a result of diabetes by 21%, and drops by 37% other complications, like blindness and loss of feeling in hands and feet, according to a 2000 study. -
Google Is Training Machines To Predict When a Patient Will Die (bloomberg.com)
A newly developed tool by Google can forecast a host of patient outcomes, including how long people may stay in hospitals, their odds of re-admission and chances they will soon die. Google documented some of this tool's abilities in May; in one instance, Google's tool estimated, by taking 175,639 data points into consideration, that a particular patient's odds at dying during her stay at the hospital was 19.9 percent, up from 9.3 percent that the hospital's computers had estimated. Now Bloomberg reports what Google intends to do with this new tool next. From the report: Google's next step is moving this predictive system into clinics, AI chief Jeff Dean told Bloomberg News in May. Dean's health research unit -- sometimes referred to as Medical Brain -- is working on a slew of AI tools that can predict symptoms and disease with a level of accuracy that is being met with hope as well as alarm. Inside the company, there's a lot of excitement about the initiative.
"They've finally found a new application for AI that has commercial promise," one Googler says. Since Alphabet's Google declared itself an "AI-first" company in 2016, much of its work in this area has gone to improve existing internet services. The advances coming from the Medical Brain team give Google the chance to break into a brand new market -- something co-founders Larry Page and Sergey Brin have tried over and over again. Software in health care is largely coded by hand these days. In contrast, Google's approach, where machines learn to parse data on their own, "can just leapfrog everything else," said Vik Bajaj, a former executive at Verily, an Alphabet health-care arm, and managing director of investment firm Foresite Capital. "They understand what problems are worth solving," he said. "They've now done enough small experiments to know exactly what the fruitful directions are." The report adds that, among other things, Google's tool has the ability to sift through notes buried in PDFs or scribbled on old charts. -
Antarctica Is Melting Three Times As Fast As a Decade Ago (nytimes.com)
An anonymous reader writes: Between 60 and 90 percent of the world's fresh water is frozen in the ice sheets of Antarctica, a continent roughly the size of the United States and Mexico combined. If all that ice melted, it would be enough to raise the world's sea levels by roughly 200 feet. While that won't happen overnight, Antarctica is indeed melting, and a study published Wednesday in the journal Nature shows that the melting is speeding up. The rate at which Antarctica is losing ice has tripled since 2007, according to the latest available data. The continent is now melting so fast, scientists say, that it will contribute six inches (15 centimeters) to sea-level rise by 2100. That is at the upper end of what the Intergovernmental Panel on Climate Change has estimated Antarctica alone could contribute to sea level rise this century.
"Around Brooklyn you get flooding once a year or so, but if you raise sea level by 15 centimeters then that's going to happen 20 times a year," said Andrew Shepherd, a professor of earth observation at the University of Leeds and the lead author of the study. Even under ordinary conditions, Antarctica's landscape is perpetually changing as icebergs calve, snow falls and ice melts on the surface, forming glacial sinkholes known as moulins. But what concerns scientists is the balance of how much snow and ice accumulates in a given year versus the amount that is lost. -
'Carbon Bubble' Could Spark Global Financial Crisis, Study Warns (theguardian.com)
An anonymous reader quotes a report from The Guardian: The existence of a "carbon bubble" -- assets in fossil fuels that are currently overvalued because, in the medium and long-term, the world will have to drastically reduce greenhouse gas emissions -- has long been proposed by academics, activists and investors. The new study, published on Monday in the journal Nature Climate Change, shows that a sharp slump in the value of fossil fuels would cause this bubble to burst, and posits that such a slump is likely before 2035 based on current patterns of energy use. Crucially, the findings suggest that a rapid decline in fossil fuel demand is no longer dependent on stronger policies and actions from governments around the world. Instead, the authors' detailed simulations found the demand drop would take place even if major nations undertake no new climate policies, or reverse some previous commitments. That is because advances in technologies for energy efficiency and renewable power, and the accompanying drop in their price, have made low-carbon energy much more economically and technically attractive. -
Great Barrier Reef Has Died Five Times In Last 30,000 Years, Study Says (newsweek.com)
schwit1 quotes a report from Newsweek: You may well have heard that Australia's iconic Great Barrier Reef is dying as warmer and more acidic waters bleach the system's vibrant coral reefs. In fact, a heat wave killed nearly a third of the system's corals in 2016. Now, scientists writing in the journal Nature Geoscience have discovered the reef has bounced back from near-extinction five times in the last 30,000 years. The current stresses, however, are probably far more intense than those felt in the past.
Low sea levels 30,000 and 22,000 years ago killed coral by air exposure. The remaining reef shifted seaward and eventually bounced back. Rising sea levels -- like those we see today -- killed off the coral twice between 13,000 and 17,000 years ago. This time, coral inched close to land to survive. The reef system, the scientists think, migrated up to 60 inches a year in the face of a changing environment. The last of the five great die-offs occurred about 10,000 years ago, and was likely caused by a huge influx of sediment, a reduction in water quality and a general sea level rise. The reef system may be due for another die-off sometime in the next few thousand years "if it follows its past geological pattern," study author Jody Webster told AFP. "But whether human-induced climate change will hasten that death remains to be seen." -
Great Barrier Reef Has Died Five Times In Last 30,000 Years, Study Says (newsweek.com)
schwit1 quotes a report from Newsweek: You may well have heard that Australia's iconic Great Barrier Reef is dying as warmer and more acidic waters bleach the system's vibrant coral reefs. In fact, a heat wave killed nearly a third of the system's corals in 2016. Now, scientists writing in the journal Nature Geoscience have discovered the reef has bounced back from near-extinction five times in the last 30,000 years. The current stresses, however, are probably far more intense than those felt in the past.
Low sea levels 30,000 and 22,000 years ago killed coral by air exposure. The remaining reef shifted seaward and eventually bounced back. Rising sea levels -- like those we see today -- killed off the coral twice between 13,000 and 17,000 years ago. This time, coral inched close to land to survive. The reef system, the scientists think, migrated up to 60 inches a year in the face of a changing environment. The last of the five great die-offs occurred about 10,000 years ago, and was likely caused by a huge influx of sediment, a reduction in water quality and a general sea level rise. The reef system may be due for another die-off sometime in the next few thousand years "if it follows its past geological pattern," study author Jody Webster told AFP. "But whether human-induced climate change will hasten that death remains to be seen." -
Why Thousands of AI Researchers Are Boycotting the New Nature Journal (theguardian.com)
An anonymous reader shares an excerpt from a report via The Guardian, written by Neil Lawrence, the founding editor of the freely available journal Proceedings of Machine Learning Research: Machine learning has demonstrated that an academic field can not only survive, but thrive, without the involvement of commercial publishers. But this has not stopped traditional publishers from entering the market. Our success has caught their attention. Most recently, the publishing conglomerate Springer Nature announced a new journal targeted at the community called Nature Machine Intelligence. The publisher now has 53 journals that bear the Nature name. Should we be concerned? What would drive authors and readers towards a for-profit subscription journal when we already have an open model for sharing our ideas? Academic publishers have one card left to play: their brand. The diversity and quantity of academic research means that it is difficult for a researcher in one field to rate the work in another. Sometimes a journal's brand is used as a proxy for quality. When academics look for promotion, having papers in a "brand-name journal" can be a big help. Nature is the Rolex of academic publishing. But in contrast to Rolex, whose staff are responsible for the innovation in its watches, Nature relies on academics to provide its content. We are the watchmakers, they are merely the distributors.
Many in our research community see the Nature brand as a poor proxy for academic quality. We resist the intrusion of for-profit publishing into our field. As a result, at the time of writing, more than 3,000 researchers, including many leading names in the field from both industry and academia, have signed a statement refusing to submit, review or edit for this new journal. We see no role for closed access or author-fee publication in the future of machine-learning research. We believe the adoption of this new journal as an outlet of record for the machine-learning community would be a retrograde step. -
Why Thousands of AI Researchers Are Boycotting the New Nature Journal (theguardian.com)
An anonymous reader shares an excerpt from a report via The Guardian, written by Neil Lawrence, the founding editor of the freely available journal Proceedings of Machine Learning Research: Machine learning has demonstrated that an academic field can not only survive, but thrive, without the involvement of commercial publishers. But this has not stopped traditional publishers from entering the market. Our success has caught their attention. Most recently, the publishing conglomerate Springer Nature announced a new journal targeted at the community called Nature Machine Intelligence. The publisher now has 53 journals that bear the Nature name. Should we be concerned? What would drive authors and readers towards a for-profit subscription journal when we already have an open model for sharing our ideas? Academic publishers have one card left to play: their brand. The diversity and quantity of academic research means that it is difficult for a researcher in one field to rate the work in another. Sometimes a journal's brand is used as a proxy for quality. When academics look for promotion, having papers in a "brand-name journal" can be a big help. Nature is the Rolex of academic publishing. But in contrast to Rolex, whose staff are responsible for the innovation in its watches, Nature relies on academics to provide its content. We are the watchmakers, they are merely the distributors.
Many in our research community see the Nature brand as a poor proxy for academic quality. We resist the intrusion of for-profit publishing into our field. As a result, at the time of writing, more than 3,000 researchers, including many leading names in the field from both industry and academia, have signed a statement refusing to submit, review or edit for this new journal. We see no role for closed access or author-fee publication in the future of machine-learning research. We believe the adoption of this new journal as an outlet of record for the machine-learning community would be a retrograde step. -
Missing Climate Goals Could Cost the World $20 Trillion (technologyreview.com)
An anonymous reader shares a report: There are trillions of reasons for the world to prevent temperatures from rising more than 1.5C, the aspirational target laid out in the Paris climate agreement, according to a new study. If nations took the necessary actions to meet that goal, rather than the increasingly discussed 2C objective, there's a 60 percent chance it would save the world more than $20 trillion, according to new work published this week in Nature by scientists at Stanford. That figure is far higher than what most experts think it will cost to cut emissions enough to achieve the 1.5C target. Indeed, one study put the price tag in the hundreds of billions of dollars. If temperatures rise by 3C, it will knock out an additional 5 percent of GDP. That's the entire planet's GDP. -
In Virtual Reality, How Much Body Do You Need? (nytimes.com)
An anonymous reader quotes a report from The New York Times: Will it soon be possible to simulate the feeling of a spirit not attached to any particular physical form using virtual or augmented reality? If so, a good place to start would be to figure out the minimal amount of body we need to feel a sense of self, especially in digital environments where more and more people may find themselves for work or play. It might be as little as a pair of hands and feet, report Dr. Michiteru Kitazaki and a Ph.D. student, Ryota Kondo. In a paper published Tuesday in Scientific Reports, they showed that animating virtual hands and feet alone is enough to make people feel their sense of body drift toward an invisible avatar (Warning: source may be paywalled; alternative source). Their work fits into a corpus of research on illusory body ownership, which has challenged understandings of perception and contributed to therapies like treating pain for amputees who experience phantom limb.
Using an Oculus Rift virtual reality headset and a motion sensor, Dr. Kitazaki's team performed a series of experiments in which volunteers watched disembodied hands and feet move two meters in front of them in a virtual room. In one experiment, when the hands and feet mirrored the participants' own movements, people reported feeling as if the space between the appendages were their own bodies. In another experiment, the scientists induced illusory ownership of an invisible body, then blacked out the headset display, effectively blindfolding the subjects. The researchers then pulled them a random distance back and asked them to return to their original position, still virtually blindfolded. Consistently, the participants overshot their starting point, suggesting that their sense of body had drifted or "projected" forward, toward the transparent avatar. -
US Government Wants To Start Charging For Landsat, the Best Free Satellite Data On Earth (qz.com)
The U.S. government may begin charging users for access to five decades of satellite images of Earth. Quartz reports: Nature reports that the Department of Interior has asked an advisory board to consider the consequences of charging for the data generated by the Landsat program, which is the largest continuously collected set of Earth images taken in space and has been freely available to the public since 2008. Since 1972, Landsat has used eight different satellites to gather images of the Earth, with a ninth currently slated for a December 2020 launch. The data are widely used by government agencies, and since it became free, by an increasing number of academics, private companies and journalists. "As of March 31, 2018, more than 75 million Landsat scenes have been downloaded from the USGS-managed archive!" the agency noted on the 10th anniversary of the program.
Now, the government says the cost of sharing the data has grown as more people access it. Advocates for open data say the public benefit produced through research and business activity far outweigh those costs. A 2013 survey cited by Nature found that the dataset generated $2 billion in economic activity, compared to an $80 million budget for the program. -
First Measurement of Distribution of Pressure Inside a Proton (phys.org)
Okian Warrior shares a report from Phys.Org: Inside every proton in every atom in the universe is a pressure cooker environment that surpasses the atom-crushing heart of a neutron star. That's according to the first measurement of a mechanical property of subatomic particles, the pressure distribution inside the proton, which was carried out by scientists at the Department of Energy's Thomas Jefferson National Accelerator Facility. The nuclear physicists found that the proton's building blocks, the quarks, are subjected to a pressure of 100 decillion Pascal (1035) near the center of a proton, which is about 10 times greater than the pressure in the heart of a neutron star. The result was recently published in the journal Nature. -
NASA Says Humans Are Causing Massive Changes In Location of Water Around the World (desertsun.com)
Using measurements from Earth-observing satellites, NASA scientists have found that humans have dramatically altered the location of water around the world. "The team of researchers analyzed 14 years of data from NASA's twin GRACE satellites and studied regions that have seen large increases or decreases in the total amount of freshwater, including water in lakes and rivers and water stored in underground aquifers, soil, snow and ice," reports The Desert Sun. From the report: The scientists examined precipitation trends and other data to determine the most likely causes of these huge losses and gains of water around the world. Their findings in a new study reveal that of the 34 "hotspots" of water change in places from California to China, the trends in about two-thirds of those areas may be linked to climate change or human activities, such as excessive groundwater pumping in farming regions. In eight of the 34 regions, the researchers said the trends reflect "possible" or "probable" impacts of climate change, including losses of ice sheets in Greenland and Antarctica, precipitation increases in the high latitudes of Eurasia and North America, the retreat of Alaska's glaciers and melting ice fields in Patagonia.
They ascribed changes in 12 regions to natural variability, including a progression from a dry period to a wet period in the northern Great Plains, a drought in eastern Brazil and wetter periods in the Amazon and tropical West Africa. In 14 of the areas -- more than 40 percent of the hotspots -- the scientists associated the water shifts partially or largely with human activity. That included groundwater depletion combined with drought in Southern California and the southern High Plains from Kansas to the Texas Panhandle, as well as in the northern Middle East, northern Africa, southern Russia, Ukraine and Kazakhstan. The first-of-its-kind study has been published in the journal Nature. -
AI Trained To Navigate Develops Brain-Like Location Tracking (arstechnica.com)
An anonymous reader quotes a report from Ars Technica: Now that DeepMind has solved Go, the company is applying DeepMind to navigation. Navigation relies on knowing where you are in space relative to your surroundings and continually updating that knowledge as you move. DeepMind scientists trained neural networks to navigate like this in a square arena, mimicking the paths that foraging rats took as they explored the space. The networks got information about the rat's speed, head direction, distance from the walls, and other details. To researchers' surprise, the networks that learned to successfully navigate this space had developed a layer akin to grid cells. This was surprising because it is the exact same system that mammalian brains use to navigate. More DeepMind experiments showed that only the neural networks that developed layers that "resembled grid cells, exhibiting significant hexagonal periodicity (gridness)," could navigate more complicated environments than the initial square arena, like setups with multiple rooms. And only these networks could adjust their routes based on changes in the environment, recognizing and using shortcuts to get to preassigned goals after previously closed doors were opened to them. The study has been reported in the journal Science. -
Einstein's 'Spooky Action' Has Been Demonstrated On a Massive Scale For the First Time (sciencealert.com)
schwit1 shares a report from ScienceAlert: For the first time, scientists have managed to show quantum entanglement -- which Einstein famously described as "spooky action at a distance" -- happening between macroscopic objects, a major step forward in our understanding of quantum physics. Quantum entanglement links particles in a way that they instantly affect each other, even over vast distances. On the surface, this powerful bond defies classical physics and, generally, our understanding of reality, which is why Einstein found it so spooky. But the phenomenon has since become a cornerstone of modern technology. Still, up until now quantum entanglement has only been demonstrated to work at the smallest of scales, in systems based on light and atoms, for example. Any attempt to increase the sizes has caused problems with stability, with the slightest of environmental disturbances breaking the connection. But new research changes all of this, by demonstrating that this "spooky action" can indeed be a reality between massive objects. We're not talking massive in the black hole sense but in the macroscopic sense -- two 15-micrometer-wide vibrating drum heads. And the next step will be to test whether those vibrations are being teleported between the two objects. The research has been published in the journal Nature. -
Scientists Discover That Uranus Smells Like Rotten Eggs (space.com)
An anonymous reader writes: According to a study published in Nature Astronomy, scientists have determined that the atmosphere of Uranus smells like rotten eggs. The smell of Uranus was determined by the use of an Near-Infrared Integral Field Spectrometer (NIFS), an instrument that allows scientists to determine what an atmosphere is composed of based upon the reflections of sunlight that bounce off of it. Specifically, the clouds in Uranus' upper atmosphere consist of hydrogen sulfide, the molecule that makes rotten eggs so stinky. "If an unfortunate human were ever to descend through Uranus' clouds, they would be met with very unpleasant and odiferous conditions," study lead author Patrick Irwin, of Oxford University in England, said in a statement. But that wayward pioneer would have bigger problems, he added: "Suffocation and exposure in the negative 200 degrees Celsius [minus 328 degrees Fahrenheit] atmosphere, made of mostly hydrogen, helium, and methane, would take its toll long before the smell." -
Since 2016, Half of All Coral In the Great Barrier Reef Has Died (theatlantic.com)
A new paper, published Wednesday in the journal Nature, reports that the Great Barrier Reef has lost more than half of its corals since 2016. The authors inspected every one of its reefs, surveying them on an almost species-by-species basis, and found the damage to be widespread across the entire ecosystem. "Two of its most recognizable creatures -- the amber-colored staghorn corals, and the flat, fanlike tabular corals -- suffered the worst casualties," reports The Atlantic. From the report: "On average, across the Great Barrier Reef, one in three corals died in nine months," said Terry Hughes, an author of the paper and the director of the ARC Center of Excellence for Coral Reef Studies, the Australian government's federal research program devoted to corals. "You could say [the ecosystem] has collapsed. You could say it has degraded. I wouldn't say that's wrong," Hughes said. "A more neutral way of putting it is that it has transformed into a completely new system that looks differently, and behaves differently, and functions differently, than how it was three years ago."
In the summer months of 2017, warm waters again struck the reef and triggered another bleaching event. This time, the heat hit the reef's middle third. Hughes and his team have not published a peer-reviewed paper on that event, but he shared early survey results with me. Combined, he said, the back-to-back bleaching events killed one in every two corals in the Great Barrier Reef. It is a fact almost beyond comprehension: In the summer of 2015, more than 2 billion corals lived in the Great Barrier Reef. Half of them are now dead. What caused the devastation? Hughes was clear: human-caused global warming. The accumulation of heat-trapping pollution in the atmosphere has raised the world's average temperature, making the oceans hotter and less hospitable to fragile tropical corals. -
Researchers Find Genetic Cause For Alzheimer's, Possible Method To Reverse It (upi.com)
schwit1 quotes UPI: Scientists at an independent biomedical research institution have reported a monumental breakthrough: The cause of the primary genetic risk factor for Alzheimer's disease, and a possible cure for the disease. Researchers at Gladstone Institutes in San Francisco identified the primary genetic risk factor for the disease, a gene called apoE4... Their findings were published this week in the journal Nature Medicine... By treating human apoE4 neurons with a structure corrector, it eliminated the signs of Alzheimer's disease, restored normal function to the cells and improved cell survival.
The study's senior investigator says he's already working with a San Francisco pharmaceutical startup to develop the approach and move towards clinical trials, adding that "we are working to accelerate the timeline as much as possible." -
Japan Team Maps 'Semi-Infinite' Trove of Rare Earth Elements (japantimes.co.jp)
schwit1 quotes a report from The Japan Times: Japanese researchers have mapped vast reserves of rare earth elements in deep-sea mud, enough to feed global demand on a "semi-infinite basis," according to a new study. The deposit, found within Japan's exclusive economic zone waters, contains more than 16 million tons of the elements needed to build high-tech products ranging from mobile phones to electric vehicles, according to the study, released Tuesday in the journal Scientific Reports. The team, comprised of several universities, businesses and government institutions, surveyed the western Pacific Ocean near Minamitori Island. In a sample area of the mineral-rich region, the team's survey estimated 1.2 million tons of "rare earth oxide" is deposited there, said the study, conducted jointly by Waseda University's Yutaro Takaya and the University of Tokyo's Yasuhiro Kato, among others. The finding extrapolates that a 2,500-sq. km region off the southern Japanese island should contain 16 million tons of the valuable elements, and "has the potential to supply these metals on a semi-infinite basis to the world," the study said. -
One-Degree Rise In Temperature Causes Ripple Effect In World's Largest High Arctic Lake (folio.ca)
An anonymous reader quotes a report from FOLIO Magazine: A 1 C increase in temperature has set off a chain of events disrupting the entire ecology of the world's largest High Arctic lake. "The amount of glacial meltwater going into the lake has dramatically increased," said Martin Sharp, a University of Alberta glaciologist who was part of a team of scientists that documented the rapid changes in Lake Hazen on Ellesmere Island over a series of warm summers in the last decade. "Because it's glacial meltwater, the amount of fine sediment going into the lake has dramatically increased as well. That in turn affects how much light can get into the water column, which may affect biological productivity in the lake." The changes resulted in algal blooms and detrimental changes to the Arctic char fish population, and point to a near certain future of summer ice-free conditions. The findings document an unprecedented shift from the previous three centuries, challenging scientists' expectations of how such a large system could respond so rapidly to a one-degree rise. The study has been published in the journal Nature Communications. -
Center of the Milky Way Has Thousands of Black Holes, Study Shows (npr.org)
New submitter xonen shares a report from NPR: For decades, scientists have thought that black holes should sink to the center of galaxies and accumulate there. But scientists had no proof that these exotic objects had actually gathered together in the center of the Milky Way. Isolated black holes are almost impossible to detect, but black holes that have a companion -- an orbiting star -- interact with that star in ways that allow the pair to be spotted by telltale X-ray emissions. The team searched for those signals in a region stretching about three light-years out from our galaxy's central supermassive black hole. What they found there: a dozen black holes paired up with stars. Finding so many in such a small region is significant, because until now scientists have found evidence of only about five dozen black holes throughout the entire galaxy. What they've found should help theorists make better predictions about how many cosmic smashups might occur and generate detectable gravitational waves. The study has been published in the journal Nature. -
Hubble Space Telescope Spots the Farthest Known Star (engadget.com)
Researchers using Hubble space telescope data have spotted Icarus (aka MACS J1149+2223 Lensed Star 1), a blue supergiant whose light was emitted when it was 9 billion light years away from Earth -- over 100 times farther than the previous record-setter. According to Engadget, "They captured the star thanks to a rare, ideal gravitational lensing effect where the star's light was magnified not only by the gravity of an in-between galaxy cluster 5 billion light years from Earth, but by a star inside that cluster." From the report: Observers had been keeping close watch on the cluster since 2014, when they'd detected a supernova that turned out to be present in a galaxy 9 billion light years away. They realized Icarus was present in April 2016, when a point of light near the supernova seemed to change brightness. Don't get too attached to this new discovery. With this kind of distance, Icarus has long-since turned into a neutron star or black hole. The findings are still advancing science in ways you might not expect, however. As the Guardian noted, the Icarus study ruled out a theory that dark matter consists of black holes. If that had been the case, they would have brightened Icarus even more. And if nothing else, this proves that humanity can detect more than just the largest and brightest celestial objects at these kinds of distances. -
'Nature' Explores Why So Many Postgrads Have Bad Mental Health (nature.com)
An anonymous reader writes: This week Nature tweeted that the rates of depression and anxiety reported by postgraduate students were six times higher than in the general population -- and received more than 1,200 retweets and received 170 replies. "This is not a one dimensional problem. Financial burden, hostile academia, red tape, tough job market, no proper career guidance. Take your pick," read one response. "Maybe being told day in, day out that the work you spend 10+ hrs a day, 6-7 days a week on isn't good enough," said another.
The science magazine takes this as more proof that "there is a problem among young scientists. Too many have mental-health difficulties, and too many say that the demands of the role are partly to blame. Neither issue gets the attention it deserves." They're now gathering stories from postgraduates about mental-health issues, and vowing to give the issue more coverage. "There is a problem with the culture in science, and it is one that loads an increasing burden on the shoulders of younger generations. The evidence suggests that they are feeling the effects. (Among the tweets, one proposed solution to improving the PhD is to 'treat it like professional training instead of indentured servitude with no hope of a career at the end?'.)" -
'Nature' Explores Why So Many Postgrads Have Bad Mental Health (nature.com)
An anonymous reader writes: This week Nature tweeted that the rates of depression and anxiety reported by postgraduate students were six times higher than in the general population -- and received more than 1,200 retweets and received 170 replies. "This is not a one dimensional problem. Financial burden, hostile academia, red tape, tough job market, no proper career guidance. Take your pick," read one response. "Maybe being told day in, day out that the work you spend 10+ hrs a day, 6-7 days a week on isn't good enough," said another.
The science magazine takes this as more proof that "there is a problem among young scientists. Too many have mental-health difficulties, and too many say that the demands of the role are partly to blame. Neither issue gets the attention it deserves." They're now gathering stories from postgraduates about mental-health issues, and vowing to give the issue more coverage. "There is a problem with the culture in science, and it is one that loads an increasing burden on the shoulders of younger generations. The evidence suggests that they are feeling the effects. (Among the tweets, one proposed solution to improving the PhD is to 'treat it like professional training instead of indentured servitude with no hope of a career at the end?'.)" -
AI Tool, Which Has Digested Nearly Every Reaction Ever Performed, Can Invent New Ways To Create Complex Molecules (nature.com)
An anonymous reader shares a research paper: Researchers have developed a 'deep learning' computer program that produces blueprints for the sequences of reactions needed to create small organic molecules, such as drug compounds. The pathways that the tool suggests look just as good on paper as those devised by human chemists. The tool is not the first software to wield AI instead of human skill and intuition. Yet chemists hail the development as a milestone, saying that it could speed up the process of drug discovery and make organic chemistry more efficient. "What we have seen here is that this kind of artificial intelligence can capture this expert knowledge," says Pablo Carbonell, who designs synthesis-predicting tools at the University of Manchester, UK, and was not involved in the work. He describes the effort as "a landmark paper."
[...] Chemists have conventionally scoured lists of reactions recorded by others, and drawn on their own intuition to work out a step-by-step pathway to make a particular compound. They usually work backwards, starting with the molecule they want to create and then analysing which readily available reagents and sequences of reactions could be used to synthesize it -- a process known as retrosynthesis, which can take hours or even days of planning. The new AI tool, developed by Marwin Segler, an organic chemist and artificial-intelligence researcher at the University of Munster in Germany, and his colleagues, uses deep-learning neural networks to imbibe essentially all known single-step organic-chemistry reactions -- about 12.4 million of them. This enables it to predict the chemical reactions that can be used in any single step. The tool repeatedly applies these neural networks in planning a multi-step synthesis, deconstructing the desired molecule until it ends up with the available starting reagents.