Welcome to the Saturday Science Edition of Overnight News Digest
Overnight News Digest is a regular daily feature which provides noteworthy news items and commentary from around the world. The editorial staff includes side pocket, maggiejean, wader, Doctor RJ, rfall, and JML9999.
Neon Vincent is our editor-in-chief.
Special thanks go to Magnifico for starting this venerable series.
Astronomy
Telescopes Give Shape To Furious Black Hole Winds This discovery that the winds blow in all directions has given astronomers their first opportunity to measure the strength of these ultra-fast winds and prove they are powerful enough to inhibit the host galaxy’s ability to make new stars. NASA’s Nuclear Spectroscopic Telescope Array (NuSTAR) and the European Space Agency’s (ESA) XMM-Newton are showing that fierce winds from a supermassive black hole blow outward in all directions — a phenomenon that had been suspected, but difficult to prove until now. [...] “We know black holes in the centers of galaxies can feed on matter, and this process can produce winds. This is thought to regulate the growth of the galaxies,” said Fiona Harrison of the California Institute of Technology (Caltech) in Pasadena. “Knowing the speed, shape, and size of the winds, we can now figure out how powerful they are.” Supermassive black holes blast matter into their host galaxies with X-ray-emitting winds traveling at up to one-third the speed of light. In the new study, astronomers determined PDS 456, an extremely bright black hole known as a quasar more than 2 billion light-years away, sustains winds that carry more energy every second than is emitted by more than a trillion Suns. “Now we know quasar winds significantly contribute to mass-loss in a galaxy, driving out its supply of gas, which is fuel for star formation,” said Emanuele Nardini of Keele University in England. astronomy
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Cepheids Map Milky Way – And Beyond How many spiral arms does the Milky Way have? How far does its disk extend? Even the simplest questions about the galaxy we call home are still up for debate. Now, in what is likely only the beginning of a larger effort, three independent studies are using a famous class of pulsating star to map out hidden reaches of the Milky Way. Classical Cepheid variables are aging massive stars whose fame derives from their bid to avoid gravitational collapse. Having run out of hydrogen to fuse in their cores, they struggle to burn shells of helium instead, puffing up and deflating at a rate directly tied to their intrinsic luminosity. That deceptively simple relation, which Henrietta Leavitt discovered in 1908, has led to profound revisions in everything from the shape and extent of our galaxy to the fate of the universe. Now astronomers are increasingly studying Cepheids in near-infrared light, and they are beginning to pierce the veils of dust and gas that enshroud the Milky Way. “Our knowledge of galactic structure is rather unsatisfactory . . . no consensus exists,” says Daniel Majaess (Saint Mary’s University and Mount Saint Vincent University, Canada). skyandtelescope
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Hubble Gets Best View Of Circumstellar Debris Disk Distorted By Planet Astronomers have used NASA’s Hubble Space Telescope to take the most detailed edge on picture to date of a large disk of gas and dust encircling the 20 million-year-old star Beta Pictoris. Beta Pictoris is the only star to date where astronomers have detected an embedded giant planet in a directly-imaged debris disk. The planet, which was discovered in 2009, goes around the star once every 18 to 20 years. This allows scientists to study in a comparably short time how a large planet distorts the massive gas and dust encircling the star. These observations should yield new insights into how planets are born around young stars. The new visible-light Hubble image traces the disk to within about 650 million miles of the star. The giant planet orbits at 900 million miles, and was directly imaged in infrared light by the European Southern Observatory’s Very Large Telescope six years ago. “Some computer simulations predicted a complicated structure for the inner disk due to the gravitational pull by the giant planet. The new images reveal the inner disk and confirm the predicted structures. This finding validates models that will help us to deduce the presence of other exoplanets in other disks,” said Daniel Apai of the University of Arizona, Tucson. These structures include a warp in the inner disk caused by the giant planet. When comparing the latest 2012 images to Hubble images taken in 1997, astronomers find that the disk’s dust distribution has barely changed over 15 years despite the fact that the entire structure is orbiting the star like a carousel. This means the disk's structure is smooth and continuous, at least over the interval between the Hubble observations. nasa
Biology
New Brain Mapping Reveals Unknown Cell Types Using a process known as single cell sequencing, scientists at Karolinska Institutet have produced a detailed map of cortical cell types and the genes active within them. The study, which is published in the journal 'Science', marks the first time this method of analysis has been used on such a large scale on such complex tissue. The team studied over three thousand cells, one at a time, and even managed to identify a number of hitherto unknown types. "If you compare the brain to a fruit salad, you could say that previous methods were like running the fruit through a blender and seeing what colour juice you got from different parts of the brain," says Sten Linnarsson, senior researcher at the Department of Medical Biochemistry and Biophysics. "But in recent years we've developed much more sensitive methods of analysis that allow us to see which genes are active in individual cells. This is like taking pieces of the fruit salad, examining them one by one and then sorting them into piles to see how many different kinds of fruit it contains, what they're made up of and how they interrelate." The knowledge that all living organisms are built up of cells is almost 200 years old. Since the discovery was made by a group of 19th century German scientists, we have also learnt that the nature of a particular body tissue is determined by its constituent cells, which are, in turn, determined by which genes are active in their DNA. However, little is still known about how this happens in detail, especially as regards the brain, the body's most complex organ. In the present study, the scientists used large-scale single-cell analysis to answer some of these questions. By studying over three thousand cells from the cerebral cortex in mice, one at a time and in detail, and comparing which of the 20,000 genes were active in each one, they were able to sort the cells into virtual piles. They identified 47 different kinds of cell, including a large proportion of specialised neurons, some blood vessel cells and glial cells, which take care of waste products, protect against infection and supply nerve cells with nutrients. With the help of this detailed map, the scientists were able to identify hitherto unknown cell types, including a nerve cell in the most superficial cortical layer, and six different types of oligodendrocyte, which are cells that form the electrically insulating myelin sheath around the nerve cells. The new knowledge the project has generated can shed more light on diseases that affect the myelin, such as multiple sclerosis (MS). biologynews
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Marine Animals Tend To Evolve Toward Larger Body Size Over Time Named after American paleontologist Edward Drinker Cope, Cope’s rule was formulated in the 19th century after scientists noticed that the body sizes of terrestrial mammals such as horses generally increased over time. Researchers have attempted to test the rule in other animal groups, but the conclusions have been mixed. Corals and dinosaurs seem to follow the rule, for example, but birds and insects do not. As a result, some scientists have wondered whether the pattern observed in land mammals is a real evolutionary phenomenon or merely a statistical one resulting from random, non-selective evolution, also known as neutral drift. [...]
“As time marches forward, each species is assigned some probability of producing a new species, of remaining the same, or of going extinct, at which point it drops out of the race,” said Dr Noel Heim from the Stanford University’s Department of Geological and Environmental Sciences, the first author on the study. [...] “The degree of increase in both mean and maximum body size just aren’t well explained by neutral drift. It appears that you actually need some active evolutionary process that promotes larger sizes,” Dr Heim said.
sci-news
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Paper Test Quickly Detects Ebola, Dengue And Yellow Fever Researchers in the US have developed a silver nanoparticle-based paper test to simultaneously detect dengue, yellow fever and Ebola. This could provide a cheap and reliable diagnosis for all three diseases, that’s as quick as a home pregnancy test. The Ebola epidemic in West Africa underscores an urgent need for rapid diagnostics; quick identification and patient isolation can benefit the sick and the healthy. However, dengue, yellow fever and Ebola all initially manifest as a fever and headache, so are easily mixed up. Now, this huge problem has a tiny solution – an 8×3cm lateral flow test. Lee Gehrke and his team at the Massachusetts Institute of Technology and Harvard Medical School adapted the traditional single marker lateral flow test to diagnose several diseases at once. It costs $2, takes 10 minutes, and there is no need for a power supply, trained specialist or expensive equipment. The test is made from strips of paper containing antibodies attached to triangular silver nanoparticles of varying size according to the disease they recognize and bind to. Silver nanoparticles appear as different colours according to their size, so when a patient’s serum sample migrates through the device, distinctive colored lines appear on the paper to indicate positive results for Ebola, dengue or yellow fever. This pattern of lines can be analysed by eye but the team are also working on a mobile phone application to aid diagnosis. ‘An app could be very useful for diseases that are mosquito-spread,’ says Gehrke. ‘It adds a date and geographical stamp to the test results so the spread of disease can be followed in real-time.’ scientificamerican
Chemistry
Infrared Camouflage That Sticks US scientists have developed an adhesive tape that can help objects match the infrared reflectance of their surroundings and disguise them from being seen by infrared cameras. The flexible coating – based on a protein found in cephalopod skin – can moderate reflectance simply by stretching and may find application in military camouflage kit. Cephalopods – such as squid, octopuses and cuttlefish – are nature’s masters of disguise. Their skins contain iridophores, cells that reflect and manipulate incident light to spectacular effect. Their plasma membranes fold to encompass lamellar-like platelets containing reflectin. Reversible phosphorylation of reflectin changes the size and structure of the lamellae, changing the iridophore’s reflectance across the visible spectrum. Alon Gorodetsky’s group at the University of California, Irvine, has developed a method for coating a thin-film of reflectin onto the surface of a flexible and transparent adhesive substrate layered with graphene oxide. These ‘stickers’, transparent under normal light, can be stuck onto any surface, including conventional camouflage with precise patterning. The reflectance can be controlled by stretching, and upon heating, the inexpensive material returns to its original state. ‘The protocols for making it are very scalable – putting a thin film on a standard roll of tape isn’t difficult and requires fairly little material so it shouldn’t be much more expensive than ordinary sticky tape one finds in their desk,’ Alon tells Chemistry World. Besides stealth applications, Gorodetsky suggests that advanced versions of these materials might be used in glass coatings to regulate seasonal temperature. The team are keen to push the reflectance of reflectin-inspired materials as far as possible into the thermal infrared. ‘We hope to eventually develop autonomous clothing-integrated devices that will regulate how a person radiatively exchanges heat with their environment.’ The potential applications are exciting: ‘Wouldn’t it be neat if you had a jacket which could adapt to keep you cool on warm days and warm on cold days?’ adds Gorodetsky. Jason Slinker, an optoelectronic materials expert at the University of Texas at Dallas, US, says the material should draw great interest from the apparel industry. ‘Such a stable, reversible, responsive, and inexpensive means of enhancing clothing with broad color changing capabilities will have applications in safety and camouflage as well as aesthetic implications in fashion.’ royalsocietyofchemistry
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General Mills To Remove Antioxidant BHT From Its Cereals In the wake of a campaign by the controversial blogger Vani Hari, who goes by the name Food Babe, General Mills says it is removing the antioxidant butylated hydroxytoluene (BHT) from its cereals. The action is the latest to be trumpeted by Hari, who is not a scientist but whose blogging about food additives has the ability to make big companies jump. Last year the Subway sandwich chain removed a dough conditioner, azodicarbonamide, from its breads after similar haranguing by Hari. Many of America’s favorite cereal brands contain a dash of BHT, a synthetic antioxidant that prevents vegetable oils from going rancid. BHT may be added directly to cereal, though it is commonly added to the plastic or wax paper liner of the packaging. From there, it migrates into food. “BHT is an FDA-approved food ingredient, but we’re already well down the path of removing it from our cereals. This change is not for safety reasons but because we think consumers will embrace it,” General Mills says. The company claims the move has been under way for more than a year and was not motivated by the petition that Hari launched on Feb 5. Hari also has called on Kellogg’s to remove BHT. There is no scientific evidence that BHT is harmful in the amounts used in packaged food. Indeed, in small amounts, it may have anticancer effects similar to those provided by naturally occurring antioxidants. But studies of larger doses have shown mixed results. In some mouse and rat studies, BHT appeared to trigger cancer in the forestomach, an organ that humans don’t have. chemical&engineeringnews
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Scientists Identify Mineral That Destroys Organic Compounds, With Implications For Mars Curiosity Mission Scientists have discovered that the mineral jarosite breaks down organic compounds when it is flash-heated, with implications for Mars research. Jarosite is an iron sulphate and it is one of several minerals that NASA’s Curiosity Mission is searching for, as its presence could indicate ancient habitable environments, which may have once hosted life on the red planet. In a new study published today in the journal Astrobiology, researchers from Imperial College London and the Natural History Museum replicated a technique that one of the Curiosity Rover’s on-board instruments is using to analyse soil samples, in its quest to find organic compounds. They tested a combination of jarosite and organic compounds. They discovered that the instrument’s technique -which uses intense bursts of heat called flash-heating – broke down jarosite into sulphur dioxide and oxygen, with the oxygen then destroying the organic compounds, leaving no trace of it behind. The concern is that if jarosite is present in soil samples that Curiosity analyses, researchers may not be able to detect it because both the jarosite and any organic compounds could be destroyed by the flash-heating process. In 2014, Professor Mark Sephton, co-author of today’s study, investigated the mineral perchlorate. This mineral also causes problems for flash-heating experiments as it breaks down to give off oxygen and chlorine gas, which in turn react with any organic compounds, breaking them down into carbon dioxide and water. Professor Sephton showed that though perchlorate was problematic, scientists could potentially use the carbon dioxide resulting from the experiment to detect the presence of organic compounds in the sample being analysed. sciencedaily
Earth Science
The Effects Of Global Warming On Fisheries Assessed In New Study A report to be published Thursday in the journal Nature suggests that global warming may increase upwelling in several ocean current systems around the world by the end of this century, especially at high latitudes, and will cause major changes in marine biodiversity. Since upwelling of colder, nutrient-rich water is a driving force behind marine productivity, one possibility may be enhancement of some of the world’s most important fisheries. However, solar heating due to greenhouse warming may also increase the persistence of “stratification,” or the horizontal layering of ocean water of different temperatures. The result could be a warm, near-surface layer and a deep, cold layer. [...]
“Our modeling indicates that normally weaker upwelling toward the polar ends of upwelling-dominated regions will strengthen,” said Bruce Menge, the Wayne and Gladys Valley Professor of Marine Biology in the College of Science at Oregon State University, and co-author of the report. “Ordinarily, you would expect that an increase in upwelling would mean an increase in marine coastal productivity, and that might happen,” Menge said. “However, a thicker and warmer top later, and more stratified ocean waters may put the cold, nutrient-rich waters too deep for upwelling to bring them up, and reduce the ability of upwelling to energize the coastal ocean food web,” he said. “This could have a very negative impact on marine production and fisheries.”
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Environmental Group Steps Up Efforts To Ban Outdated Crude Oil-Carrying Trains A Valhalla-based environmental group stepped up its pressure on government officials to take measures now to ban outdated crude oil-carrying trains from the nation’s tracks. Riverkeeper made its demands in wake of two recent explosions of derailed trains carrying crude oil. [...] “What will it take for our leaders to act?” John Lipscomb, captain of Riverkeeper’s Hudson River Boat Patrol Program, said in the press release. “How many more derailments? How many more explosions? This is an unacceptable risk.” Riverkeeper’s statements come after derailments of trains carrying crude oil occurred in West Virginia and Northern Ontario, Canada. Riverkeeper urges that the U.S. Secretary of Transportation immediately issue an emergency order to, among other things, prohibit “the use of the 23,000 tank cars identified. . .as being the most vulnerable and least resilient tank cars on the rails. “These “worst” tank cars – which include both CPC-1232s and DOT-111s – should not be permitted for use in hauling any other hazardous liquids (such as tar sands crude oil). dailyfreeman
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Will Pacific Island Nations Disappear as Seas Rise? Maybe Not "If you were faced with the threat of the disappearance of your nation, what would you do?" That's the question Enele Sopoaga, the prime minister of the tiny Pacific Island nation of Tuvalu, asked fellow world leaders at the United Nations climate summit in Lima, Peru, in December. It's a question that leaders of Pacific Island states have been asking for decades. As a warming climate drives sea levels upward, low-lying island nations face an uncertain future—or no future at all, say these leaders, who warn of their nations' imminent disappearance. [...] These are desperate questions. But how real is the threat? Are island nations like Tuvalu, where most of the land is barely above sea level, destined to sink beneath the waves, like modern-day Atlantises? Not necessarily, according to a growing body of evidence amassed by New Zealand coastal geomorphologist Paul Kench, of the University of Auckland's School of Environment, and colleagues in Australia and Fiji, who have been studying how reef islands in the Pacific and Indian Oceans respond to rising sea levels. They found that reef islands change shape and move around in response to shifting sediments, and that many of them are growing in size, not shrinking, as sea level inches upward. The implication is that many islands—especially less developed ones with few permanent structures—may cope with rising seas well into the next century. nationalgeographic
Physics
Firing Up The Proton Smasher The Large Hadron Collider is being brought back to life, ready for Run II of the "world's greatest physics experiment". Cambridge physicists are among the army who keep it alive. [...] The Large Hadron Collider (LHC) had shut down for two years to upgrade following the discovery of the Higgs boson. In the main ring, 175 m underground, chunks had been cut out of the snaking tubes for essential maintenance. These tubes fire protons in opposite directions, whipping them ever faster until they almost reach the speed of light. Along the 27 km run are four 'experiments': vast machines envelop the points at which tubes intersect and particles collide to capture the results. The largest of these, ATLAS, is the size of a six-storey building. Each collision, known as an 'event', produces a splurge of elementary particles such as quarks, gluons and – as we now know – Higgs bosons. On average, events occur 40 million times a second in the LHC. The precision required for these events is exquisite. Our guide tells us to imagine two people standing six miles apart and each simultaneously firing a gun so that the bullets meet exactly head-on. Except instead of bullets, imagine needles. Inside the tunnels, engineers zip past on bicycles – the best way to get around underground unless you're a proton. Next to every lift shaft is a bike rack. In the next few months, the LHC will be switched back on. The 2012 triumph of demonstrating the Higgs boson affirmed the Standard Model: the elegant solution to the building blocks of the Universe. Now, with an anticipated almost doubling of energy for the LHC's second run, physicists are aiming to "go beyond" the Standard Model. One of the central goals is to prove or disprove the theory of supersymmetry: the "prime candidate" theory for unlocking the mystery of the dark matter in our Universe. phys.org
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Paper-Thin Lenses Could Shrink Cameras And Holographic Displays Why It Matters Holographic displays offer new ways to interact with computers and new opportunities for the entertainment industry. A new nanostructured material makes it possible to replace bulky lenses and other optical devices with a thin sheet of material such as silicon. The advance, described in the journal Science, could make it possible to shrink some professional-quality camera lenses to the thickness of a credit card. It might also enable lighter-weight, more compact full-color holographic 3-D goggles, the sort being developed by Microsoft and the Google-acquired company Magic Leap [...]. The work was inspired a year ago when Google approached Federico Capasso, a professor of applied physics at Harvard, with a challenge. He’d recently demonstrated that he could build thin, nanostructured films that could manipulate light. The films worked well with only one color, and Google wanted to know if he could he make the technology work with red, green, and blue light—the colors needed to produce full-color displays. Google says the work would be especially important for work related to Google Glass, but didn’t specify how (Google has stopped selling its Glass device as it works on improving it—see “Google Glass Is Dead; Long Live Smart Glasses”). Capasso has an agreement with Google not to talk about details of possible applications, but says his materials are useful for holographic 3-D imaging and augmented reality, in which computer-generated images appear to be overlaid on the real world. The ability to manipulate multiple colors might help Google make a full-color wearable version of the Magic Leap technology—the compact version it’s demonstrated so far only displays a green image. technologyreview
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World-Leading SuperSTEM Microscope That Can See Single Atoms Is Unveiled A new super powerful electron microscope that can pinpoint the position of single atoms was unveiled today at the Science and Technology Research Council's Daresbury Laboratory in Cheshire. The microscope will help scientists push boundaries even further in fields such as advanced materials, healthcare and power generation. The £3.7 million Nion Hermes Scanning Transmission Electron Microscope, one of only three in the world, is housed in the Engineering and Physical Sciences Research Council (EPSRC) SuperSTEM facility at Daresbury. The microscope not only allows imaging of unprecedented resolution of objects a million times smaller than a human hair, but also analysis of materials. This means that researchers will not only be able to clearly identify the atoms, but observe the strength of the bonds between them. This will improve understanding of their electronic properties when in bulk and how they may perform when used. Minister for Universities, Science and Cities, Greg Clark, said: "The UK is a world leader in the development and application of STEM (Scanning Transition Electron Microscope) techniques, and this new super-powerful microscope will ensure we remain world-class. "From developing new materials for space travel to creating a better, cheaper treatment for anaemia, this new super-powerful microscope lets UK scientists examine how materials behave at a level a million times smaller than a human hair. This exciting research will help lead to breakthroughs that will benefit not only our health but the environment too." phys.org
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