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Domain: nature.com
Stories and comments across the archive that link to nature.com.
Stories · 1,757
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12-Billion-Solar-Mass Black Hole Discovered
sciencehabit writes: A team of astronomers has discovered what is, in galactic terms, a monstrous baby: a gigantic black hole of 12 billion solar masses in a barely newborn galaxy, just 875 million years after the big bang. It's roughly 3000 times the size of our Milky Way's central black hole. To have grown to such a size in so short a time, it must have been munching matter at close to the maximum physically possible rate for most of its existence. Its large size and rate of consumption also makes it the brightest object in that distant era, and astronomers can use its bright light to study the composition of the early universe: how much of the original hydrogen and helium from the big bang had been forged into heavier elements in the furnaces of stars. -
Artificial Intelligence Bests Humans At Classic Arcade Games
sciencehabit writes The dream of an artificially intelligent computer that can study a problem and gain expertise all on its own is now reality. A system debuted today by a team of Google researchers is not clever enough to perform surgery or drive a car safely, but it did master several dozen classic arcade games, including Space Invaders and Breakout. In many cases, it surpassed the best human players without ever observing how they play. -
Researchers Block HIV Infection In Monkeys With Artificial Protein
An anonymous reader writes: Immunologists have developed a synthetic molecule that's able to attach to HIV and prevent it from interacting with healthy cells. "HIV infects white blood cells by sequentially attaching to two receptors on their surfaces. First, HIV's own surface protein, gp120, docks on the cell's CD4 receptor. This attachment twists gp120 such that it exposes a region on the virus that can attach to the second cellular receptor, CCR5. The new construct combines a piece of CD4 with a smidgen of CCR5 and attaches both receptors to a piece of an antibody. In essence, the AIDS virus locks onto the construct, dubbed eCD4-Ig, as though it were attaching to a cell and thus is neutralized." The new compound was tested in monkeys. After successively higher injections of HIV, all four monkeys who received the compound beforehand stayed from free infection. Any potential medical treatment is still a ways off — the researchers plan more trials in monkeys before involving humans in the testing. -
Mysterious Martian Plumes Discovered By Amateur Astronomers
An anonymous reader writes Amateur astronomers have spotted two clouds coming from the surface of Mars that are a mystery to the professionals. From Discovery: "The plumes extended over 500- to 1,000 kilometers (311- to 621 miles) in both north-south and east-west directions and changed in appearance daily. They were detected as the sun breached Mars' horizon in the morning, but not when it set in the evening. 'Remarkably ... the features changed rapidly, their shapes going from double blob protrusions to pillars or finger-plume-like morphologies,' scientists investigating the sightings wrote in a paper published in this week's Nature." -
One-Atom-Thick Silicene Transistors May Lead To Dramatically Faster Chips
Zothecula writes: As recently as 2010, human-made silicene – an atom-thin form of silicon – was purely theoretical. But now the exotic material has been used to make transistors, and researchers have found that silicene's electrical properties lend it extraordinary potential in powering the next generation of computer chips. The new method (abstract) of creating the silicene reduces its exposure to air. "To start, the researchers let a hot vapor of silicon atoms condense onto a crystalline block of silver in a vacuum chamber. They then formed a silicene sheet on a thin layer of silver and added a nanometer-thick layer of alumina on top. Because of these protective layers, the team could safely peel it of its base and transfer it silver-side-up to an oxidized-silicon substrate. They were then able to gently scrape some of the silver to leave behind two islands of metal as electrodes, with a strip of silicene between them." -
New Fiber Optic Signal Processing Technique Doubles Communication Distance
hypnosec writes: Researchers at University College London (UCL) have demonstrated a new technique for fiber optic signal processing that doubles the distance at which data travels error-free through transatlantic sub-marine cables. The UCL research, published in Scientific Reports, has the potential to reduce the costs of long-distance optical fiber communications as signals wouldn't need to be electronically boosted during their journey, which is important when the cables are buried underground or at the bottom of the ocean. The study reports a new way of improving the transmission distance, by undoing the interactions that occur between different optical channels as they travel side-by-side over an optical cable. By eliminating the interactions between the optical channels, researchers increase distance signals can be transmitted error-free from 3190km to 5890km, which is the largest increase ever reported for this system architecture. -
Graphene Based Display Paves Way For Semi-Transparent Electronic Devices
hypnosec writes University of Manchester and University of Sheffield researchers have managed to produce the first graphene-based LED displays, which could pave the way for efficient, flexible and semi-transparent electronic devices. The research, published in scientific journal Nature Materials [abstract; article is paywalled], shows how graphene displays and related 2D materials could be utilised to create light emitting devices for the next-generation of mobile phones, tablets and televisions to make them incredibly thin and durable. The LED device was constructed by combining different 2D crystals and emits light from across its whole surface. Being so thin, at only 10-40 atoms thick, these new components could form the basis for the first generation of semi-transparent smart devices. -
Safety Review Finds Yucca Mountain Nuclear Waste Site Was Technically Sound
siddesu writes: The U.S. Department of Energy's 2008 proposal to build a nuclear waste repository at Yucca Mountain, Nevada, was technically sound, a report by the NRC says. However, the closed-down project is unlikely to revive, as its staff has moved on, and there are few funds available to restart it. "With the release of the final two volumes of a five-part technical analysis, the commission closed another chapter on the controversial repository nearly five years after President Barack Obama abandoned the project, and more than a quarter century after the site was selected. While the staff recommended against approving construction, the solid technical review could embolden Republicans who now control both houses of Congress and would like to see Yucca Mountain revived." -
Scientists Discover How To Track Natural Errors In DNA Replication
BarbaraHudson writes Researchers figured out how to label and keep track of new pieces of DNA, and learned to follow the enzyme responsible for copying those pieces. Their research focused on enzymes called polymerases. These enzymes create small regions in DNA that act as scaffolds for the copied DNA. Scientists assumed that the body deletes the scaffolds containing errors, or mutations, and the standard computer models supported this theory. However, the actual research showed that about 1.5 percent of those erroneous scaffolds are left over, trapped within the DNA. After running models, scientists now believe they can track how DNA replicates and find the most likely areas where these scaffolds with errors turn up. The erroneous scaffolds usually appear close to genetic switches, those regions that turn on when genes activate. The mutations damage the switch, which results in genetic disease, as well as increasing the likelihood of cancer. -
We May Have Jupiter To Thank For the Nitrogen In Earth's Atmosphere
An anonymous reader writes: Nitrogen makes up about 78% of the Earth's atmosphere. It's also the 4th most abundant element in the human body. But where did all the nitrogen on Earth come from? Scientists aren't sure, but they have a new theory. Back when the solar system was just a protoplanetary disk, the ice orbiting the early Sun included ammonia, which has a nitrogen atom and three hydrogen atoms. But there needed to be a way for the nitrogen to get to the developing Earth. That's where Jupiter comes in. During its theorized Grand Tack, where it plunged into the inner solar system and then retreated outward again, it created shock waves in the dust and ice cloud surrounding the sun. These shock waves caused gentle heating of the ammonia ice, which allowed it to melt and react with chromium-bearing metal to form a mineral called carlsbergite. New research (abstract) suggests this mineral was then present when the Earth's accretion happened, supplying much of the nitrogen we would eventually need for life. -
Interior of Burnt Herculaneum Scroll Read For First Time
New submitter Solandri writes: When Mt. Vesuvius erupted in A.D. 79, it destroyed a library of classical works in Herculaneum. The papyrus scrolls weren't incinerated, but were instead carbonized by the hot gases. The resulting black carbon cylinders have mostly withstood attempts to read their contents since their discovery. Earlier attempts to unfurl the scrolls yielded some readable material, but were judged too destructive. Researchers decided to wait for newer technology to be invented that could read the scrolls without unrolling them.
Now, a team led by Dr. Vito Mocella from the National Research Council's Institute for Microelectronics and Microsystems (CNR-IMM) in Naples, Italy has managed to read individual letters inside one of the scrolls. Using a form of x-ray phase contrast tomography (abstract), they were able to ascertain the height difference (about 0.1mm) between the ink of the letters and the papyrus fibers which they sat upon. Due to the fibrous nature of the papyrus and the carbon-based ink, regular spectral and chemical analysis had thus far been unable to distinguish the ink from the paper. Further complicating the work, the scrolls are not in neat cylinders, but squashed and ruffled as the hot gases vaporized water in the papyrus and distorted the paper. -
Human Language May Have Evolved To Help Our Ancestors Make Tools
sciencehabit writes: If there's one thing that distinguishes humans from other animals, it's our ability to use language. But when and why did this trait evolve? A new study concludes that the art of conversation may have arisen early in human evolution, because it made it easier for our ancestors to teach each other how to make stone tools — a skill that was crucial for the spectacular success of our lineage. The study involved getting a number of college students to try to make their own primitive stone tools, some using language, others not. The team discovered that only those that used language were able to make effective tools. -
300 Million Year Old Fossil Fish Likely Had Color Vision
westlake writes Nature is reporting the discovery of mineralized rods and cones in a 300-million-year-old fossil fish found in Kansas. The soft tissues of the eye and brain decay rapidly after death, within 64 days and 11 days, respectively, and are almost never preserved in the fossil record — making this the first discovery of fossil rods and cones in general and the first evidence for color vision in a fossilized vertebrate eye. -
Linking Drought and Climate Change: Difficult To Do
Geoffrey.landis writes An article about the current California drought on 538 points out that even though global climate warming may exacerbate droughts, it's nearly impossible to attribute any particular drought to climate warming: "The complex, dynamic nature of our atmosphere and oceans makes it extremely difficult to link any particular weather event to climate change. That's because of the intermingling of natural variations with human-caused ones." They also cite a Nature editorial pointing out the same thing about extreme weather. -
Titan's Dunes Took Tens of Thousands of Years To Form
sciencehabit writes: Massive dunes, some of them 100 meters tall and a kilometer or more wide at their base, cover about one-eighth of Titan's surface. And they take an exceptionally long time to form, according to a new study. Using radar data gleaned by the Cassini probe when it occasionally swooped past Saturn's haze-shrouded moon, researchers conclude that it would take about 3000 Saturn years (or 88,200 Earth years) to shift Titan's dunes to the extent seen in the images. A similar phenomenon has taken place on Earth, the researchers note: The overall patterns in many large dune fields in the southwestern Sahara and the southwestern United States, shaped by the winds that blew during the most recent ice age more than 10,000 years ago, remain largely unaffected by modern winds that now blow in a different direction. -
Monochromatic Light As a Species-selective Insecticide
An anonymous reader writes: The harmful effects of ultraviolet light have been long known. But now researchers at Tohoku University in Japan claim that visible blue light is also lethal to many insects, possibly even more so than UV, even at reasonable daylight intensities. Moreover, they report that certain species are more sensitive to specific wavelengths: Given the same intensity (3x10^18 photons/sec/m^2), light in the 440-467nm range was far more lethal to fruit flies than light of longer or shorter wavelengths. The wavelength 417nm was three times as effective at killing mosquito larvae than the shorter 404nm light, contradicting the notion that higher-energy photons always cause more damage. The research has wide implications for modeling the effect of natural and manmade environmental changes on insect populations and for selectively controlling populations of certain species. -
NSF Accused of Misuse of Funds In Giant Ecological Project
An anonymous reader writes: The National Science Foundation (NSF) and a contractor have been accused by both an audit and by Congress of a significant misuse of funds in a major ecological monitoring project costing almost a half a billion dollars. From the article: "With a construction budget of $433.7 million, NEON is planned to consist of 106 sites across the United States. Arrays of sensors at each site will monitor climate change and human impacts for 30 years, building an unprecedented continental-scale data set. Although some initially doubted its merits, the allure of big-data ecology eventually won over most scientists.
But a 2011 audit of the project's proposed construction budget stalled three times when, according to the independent Defense Contract Audit Agency, NEON's accounting proved so poor that the review could not be completed. Eventually, DCAA issued an adverse ruling, concluding that nearly 36% of NEON's budget proposal was questionable or undocumented.
When the NSF green-lit the project, the agency's inspector-general ordered the audit released on 24 November, which found unallowable expenses including a $25,000 winter holiday party, $11,000 to provide coffee for employees, $3,000 for board-of-directors dinners that included alcohol, $3,000 for t-shirts and other clothes, $83,000 for "business development" and $112,000 for lobbying." -
Researchers Design DNA With New Shapes and Structures
Jason Koebler writes: The shape of DNA is a double helix, right? That's what we are taught. Well, now the answer is "not always." Researchers at the Massachusetts Institute of Technology have discovered how to program DNA to be shaped like a bowl, or a spiral, or a ring, or other shapes that aren't found in nature.
It's the latest in a string of discoveries about the underlying structure of life and the building blocks by which it's made. Recently, scientists created new nucleotides that do not exist in nature and inserted them into a living organism. And now, this: DNA can look like just about anything and can be assembled into many shapes. -
Researchers Design DNA With New Shapes and Structures
Jason Koebler writes: The shape of DNA is a double helix, right? That's what we are taught. Well, now the answer is "not always." Researchers at the Massachusetts Institute of Technology have discovered how to program DNA to be shaped like a bowl, or a spiral, or a ring, or other shapes that aren't found in nature.
It's the latest in a string of discoveries about the underlying structure of life and the building blocks by which it's made. Recently, scientists created new nucleotides that do not exist in nature and inserted them into a living organism. And now, this: DNA can look like just about anything and can be assembled into many shapes. -
The Ancestor of Humans Was an "Artist" 500,000 Years Ago
brindafella writes Our ancient ancestor, Homo erectus, around 500,000 years ago, has been shown to make doodles or patterns. So, it seems that we Homo sapiens have come from a thoughtful lineage. The zig-zag markings cut into the covering of a fossil freshwater shell were from a deposit in the main bone layer of Trinil (Java, Indonesia), the place where Homo erectus was discovered by Eugène Dubois in 1891, says Dr Stephen Munro, a palaeoanthropologist with the Australian National University. The team's testing shows the erectus doodling was from 0.54 million years to a minimum of 0.43 million years ago. This pushes back the thoughtful making of marks by hundreds of thousands of years. The thoughtful gathering of shellfish and their nutrients also points to possible explanations for the evolving of bigger brains. -
The Fastest Camera Ever Made Captures 100 Billion Frames Per Second
Jason Koebler writes A new imaging technique is able to capture images at 100 billion frames per second—fast enough to watch light interact with objects, which could eventually lead to new cloaking technologies. The camera was developed by a team at Washington University in St. Louis—for the team's first tests, it was able to visualize laser pulse reflections, photons racing through air and through resin, and "faster-than-light propagation of non-information." It can also be used in conjunction with telescopes and to image optical and quantum communications, according to lead researcher Liang Gao. -
The Fastest Camera Ever Made Captures 100 Billion Frames Per Second
Jason Koebler writes A new imaging technique is able to capture images at 100 billion frames per second—fast enough to watch light interact with objects, which could eventually lead to new cloaking technologies. The camera was developed by a team at Washington University in St. Louis—for the team's first tests, it was able to visualize laser pulse reflections, photons racing through air and through resin, and "faster-than-light propagation of non-information." It can also be used in conjunction with telescopes and to image optical and quantum communications, according to lead researcher Liang Gao. -
Nature Makes All Articles Free To View
An anonymous reader writes: Scientific journal publishers have been under pressure recently by both scientists and the public to relax their restrictive rules on the sharing of information. Now, Macmillan has announced that its Nature Publishing Group will make all research papers free to read. This will require the use of proprietary viewing software, but it's a step in the right direction. "Initial reactions to the policy have been mixed. Some note that it is far from allowing full open access to papers. "To me, this smacks of public relations, not open access," says John Wilbanks, a strong advocate of open-access publishing in science and a senior fellow at the Ewing Marion Kauffman Foundation in Kansas City, Missouri. 'With access mandates on the march around the world, this appears to be more about getting ahead of the coming reality in scientific publishing. Now that the funders call the tune and the funders want the articles on the web at no charge, these articles are going to be open anyway,' he says. But Peter Suber, director of the Office for Scholarly Communication at Harvard University in Cambridge, Massachusetts, says that the program is a step forward in that it eliminates the six-month embargo that NPG demands for free archiving of manuscripts." -
Jackie Chan Discs Help Boost Solar Panel Efficiency
wbr1 writes Apparently the pit pattern on a blu-ray disk is great at helping trap photons, rather than reflecting them. Applying this pattern to the glass in a solar panel can boost efficiency by 22%. Researchers at Northwestern tested this system with Jackie Chan discs. From the article: "To increase the efficiency of a solar panel by 22%, the researchers at Northwestern bought a copy of Police Story 3: Supercop on Blu-ray; removed the top plastic layer, exposing the recording medium beneath; cast a mold of the quasi-random pattern; and then used the mold to create a photovoltaic cell with the same pattern....The end result is a solar panel that has a quantum efficiency of around 40% — up about 22% from the non-patterned solar panel." -
Molecular Clusters That Can Retain Charge Could Revolutionize Computer Memory
jfruh writes:Computing devices have been gobbling up more and more memory, but storage tech has been hitting its limits, creating a bottleneck. Now researchers in Spain and Scotland have reported a breakthrough in working with metal-oxide clusters that can retain their charge. These molecules could serve as the basis for RAM and flash memory that will be leagues smaller than existing components (abstract). -
New Particle Collider Is One Foot Long
Jason Koebler writes The CERN particle collider is 17 miles long. China just announced a supercollider that is supposed to be roughly 49 miles long. The United States' new particle collider is just under 12 inches long. What the SLAC National Accelerator Laboratory's new collider lacks in size, it makes up for by using plasma to accelerate particles more than 500 times faster than traditional methods. In a recent test published in Nature, Michael Litos and his team were able to accelerate bunches of electrons to near the speed of light within the tiny chamber." -
Photon Pair Coupled in Glass Fiber
Trachman writes: Austrian scientists have discovered a way to couple photon pairs. When two identical photons are coupled and the phase of one is changed, then thanks to the magic of quantum mechanics, the phase of the other photon also changes (abstract). Scientists predict this can advance quantum optics and quantum computations, taking us a step closer to having data transmissions secure from the nosy agencies of the world.
If any of you have expertise in this area, could you share your thoughts on the essence of this discovery and its associated potential practical applications? -
MIT Professor Advocates Ending Asteroid Redirect Mission To Fund Asteroid Survey
MarkWhittington writes Professor Richard Binzel published a commentary in the journal Nature that called for two things. He proposed that NASA cancel the Asteroid Redirect Mission currently planned for the early 2020s. Instead, he would like the asteroid survey mandated by the George E. Brown, Jr. Near-Earth Object Survey Act of 2005, part of the 2005 NASA Authorization Act, funded at $200 million a year. Currently NASA funds the survey at $20 million a year, considered inadequate to complete the identification of 90 percent of hazardous near-Earth objects 140 meters or greater by 2020 as mandated by the law. -
The Most Highly Cited Scientific Papers of All Time
bmahersciwriter writes Citation is the common way that scientists nod to the important and foundational work that preceded their own and the number of times a particular paper is cited is often used as a rough measure of its impact. So what are the most highly cited papers in the past century plus of scientific research? Is it the determination of DNA's structure? The identification of rapid expansion in the Universe? No. The top 100 most cited papers are actually a motley crew of methods, data resources and software tools that through usability, practicality and a little bit of luck have propelled them to the top of an enormous corpus of scientific literature. -
Detritus From Cancer Cells May Infect Healthy Cells
bmahersciwriter writes Tiny bubbles of cell membrane — called exosomes — are shed by most cells. Long thought to be mere trash, researchers had recently noticed that they often contain short, regulatory RNA molecules, suggesting that exosomes may be one way that cells communicate with one another. Now, it appears that RNA in the exosomes shed by tumor cells can get into healthy cells and 'transform' them, putting them on the path to becoming cancerous themselves. -
Astronomers Find Brightest Pulsar Ever Observed
An anonymous reader writes: Astronomers using the Chandra X-ray Observatory and the NuSTAR satellite have discovered a pulsar so bright that it challenges how scientists think pulsars work. While observing galaxy M82 in hopes of spotting supernovae, the researchers found an unexpected source of X-rays very close to the galaxy's core. It was near another source, thought to be a black hole. But the new one was pulsing, which black holes don't do. The trouble is that according to known pulsar models, it's about 100 times brighter than the calculated limits to its luminosity (abstract). Researchers used a different method to figure out its mass, and the gap shrank, but it's still too bright to fit their theories. -
Australian Physicists Build Reversible Tractor Beam
An anonymous reader writes: Physicists at Australian National University have developed a tiny tractor beam that improves in several ways upon previous attempts. First, it operates on scales which, while still tiny, are higher than in earlier experiments. The beam can move particles up to 200 microns in diameter, and it can do so over a distance of 20 cm. "Unlike previous techniques, which used photon momentum to impart motion, the ANU tractor beam relies on the energy of the laser heating up the particles and the air around them (abstract). The ANU team demonstrated the effect on gold-coated hollow glass particles. The particles are trapped in the dark center of the beam. Energy from the laser hits the particle and travels across its surface, where it is absorbed creating hotspots on the surface. Air particles colliding with the hotspots heat up and shoot away from the surface, which causes the particle to recoil, in the opposite direction. To manipulate the particle, the team move the position of the hotspot by carefully controlling the polarization of the laser beam." -
Scientists Find Rats Aren't Smarter Than Mice, and That's Important
HughPickens.com writes: There has long been a clear hierarchy of intelligence in the psychology lab, with monkeys are at the top, then rats, and finally mice at the bottom, "cute and fluffy but not all that bright." For at least a hundred years, researchers have used rats in their psychology experiments, assuming that they were the smarter of the two lab rodents. Now, Rose Eveleth reports at The Atlantic that new research shows this might not be true, suggesting mice can perform decision-making tasks in the lab just as well as rats can. "Anything we could train a rat to do we could train a mouse to do as well," says Tony Zador. This finding is important because using mice in experiments instead of rats could open up all kinds of new research options. For one thing, scientists have been able to manipulate a mouse's genome in really useful ways, silencing certain genes to figure out what role they play. There are mouse models for everything from Alzheimer's to Parkinson's. Being able to put those mice through the paces of a psychology experiment could help researchers connect diseases with the behaviors they impact.
So where did this idea that rats are smarter than mice come from, anyway? Zador says it's a historical bias. "There was 100 years of practice in training rats. And basically when people tried to treat the mice in exactly the way they treated the rats, the rats seemed smarter," says Zador. In other words, "over the course of 100 years people had figured out how to train rats, and that mice aren't rats." You might think that mice and rats would be basically the same when it comes to these kinds of things, but Zador points out that mice and rats diverged somewhere between 12 and 24 million years ago. For comparison, humans and chimpanzees split somewhere between 5 and 7 million years ago. So it's no surprise that mice behave differently than rats, and that the difference impacts their training in the lab. "The mouse is uniquely placed at the interface between experimental access and behavioral complexity, making it an ideal model for the study of adaptive decision-making. Successful behavioral paradigms, however, rely on targeting designs to the idiosyncrasies of the mouse from the outset, rather than simply assuming that mice are little rats." -
Smart Battery Tells You When It's About To Explode
sciencehabit writes Material scientists have found a clever way to alert users of damaged batteries before any hazard occurs. A typical lithium-ion cell consists of a lithium oxide cathode and a graphite anode, separated by a thin, porous polymer sheet that allows ions to travel between the electrodes. When the cell is overcharged, microscopic chains of lithium, called "dendrites," sprout from the anode and pierce through the polymer separator until they touch the cathode. An electrical current passing through the dendrites to the cathode can short-circuit the cell, which causes overheating and, in some cases, fire. Attempts to stop dendrite formation have met with limited success, so the researchers tried something different. They built a "smart" separator by sandwiching a 50-nanometer thin copper layer between two polymer sheets and connecting the copper layer to a third electrode for voltage measurement. When the dendrites reach the separator, the voltage between the anode and the copper layer drops to zero, alerting users that they should change the damaged battery while it is still operating safely—disaster averted. -
Hawking Radiation Mimicked In the Lab
Annanag writes *Nothing* escapes a black hole, right? Except 40 years ago Stephen Hawking threw a spanner in the works by suggesting that, courtesy of quantum mechanics, some light particles can actually break free of a black hole's massive pull. Then you have the tantalizing question of whether information can also escape, encoded in that so-called 'Hawking radiation'. The only problem being that no one has ever been able to detect Hawking radiation being emitted from a black hole. BUT a physicist has now come closer than ever before to creating an imitation of a black hole event horizon in the lab, opening up a potential avenue for investigating Hawking radiation and exploring how quantum mechanics and general relativity might be brought together. -
Nearly 700 Genetic Factors Found To Influence Human Adult Height
damn_registrars writes: A consortium of scientists from many different countries reviewed genome-wide association study data sets of over 250,000 individuals in a search for genetic factors that influence adult height. Looking at Single Nucleotide Polymorphisms, the researchers found 697 distinct genetic markers that can explain some 20 percent of the heritability of human adult height. Previous studies had found around 180 such markers, but the larger sample set increased the ability to detect these changes, both within genes and in non-coding regions. Genes found in this set included ones from pathways not previously connected to skeletal growth.
This study is also significant for the sample size, which allows it to address whether the data from such large sets has a tendency to converge or diverge on genetic pathways; this study particularly favors the latter, which is of great utility toward studying other polygenetic conditions in the future. The original paper is likely paywalled, however the abstract is available for free and some of the collaborators behind it have other bits available for free in the meantime. -
Physicists Find Clue as To Why the DNA Double Helix Twists To the Right
New submitter Annanag writes Most organic molecules have left- or right-handed versions, mirror images of each other, just like gloves. For some reason, life always seems to favor one version over the other — the DNA double helix in its standard form always twists like a right-handed screw, for example. But why this preference for left or right happens has always been a mystery. Now, in an experiment that took 13 years to perfect, physicists have found hints that this asymmetry of life could have been caused by electrons from nuclear decay in the early days of evolution. -
Water Discovered In Exoplanet Atmosphere
PattonPending sends news of the discovery of the smallest exoplanet yet to have water vapor in its atmosphere. Astronomers have detected water vapor in the atmosphere of a planet that orbits a star far beyond our solar system. Observations of the Neptune-sized planet, which lies 120 light years from Earth in the constellation of Cygnus, revealed that its atmosphere was mostly hydrogen with around 25% made up from water va-pour. Until now, researchers have been frustrated in their efforts to study the atmospheres of planets much smaller than Jupiter because their skies were thick with clouds. The problem was so persistent that astronomers had begun to think that all warm, small planets formed with substantial cloud cover. But writing in the journal Nature, scientists in the U.S. describe how they found a Neptune-sized planet with cloud-free skies, enabling them to make detailed measurements of a small planet's atmosphere for the first time. -
Study Finds Link Between Artificial Sweeteners and Glucose Intolerance
onproton (3434437) writes The journal Nature released a study today that reveals a link between the consumption of artificial sweeteners and the development of glucose intolerance [note: abstract online; paper itself is paywalled], a leading risk factor for the development of type 2 diabetes, citing a critical alteration of intestinal bacteria. Paradoxically, these non-caloric sweeteners, which can be up to 20,000 times sweeter than natural sugars, are often recommended to diabetes patients to control blood glucose levels. Sugar substitutes have come under additional fire lately from studies showing that eating artificially sweetened foods can lead to greater overall calorie consumption and even weight gain. While some, especially food industry officials, remain highly skeptical of such studies, more research still needs to be done to determine the actual risks these substances may pose to health. -
Scientists Twist Radio Beams To Send Data At 32 Gigabits Per Second
concertina226 writes Scientists from three international universities have succeeded in twisting radio beams in order to transfer data at the speed of 32 gigabits per second, which is 30 times faster than 4G LTE wireless technology in use today. The researchers, led by Alan Willner, an electrical engineering professor with the University of Southern California Viterbi School of Engineering, successfully demonstrated data transmission rates of 32 gigabits per second across 2.5m of free space in a basement laboratory. -
Artificial Spleen Removes Ebola, HIV Viruses and Toxins From Blood Using Magnets
concertina226 writes Harvard scientists have invented a new artificial spleen that is able to clear toxins, fungi and deadly pathogens such as Ebola from human blood, which could potentially save millions of lives. When antibiotics are used to kill them, dying viruses release toxins in the blood that begin to multiply quickly, causing sepsis, a life-threatening condition whereby the immune system overreacts, causing blood clotting, organ damage and inflammation. To overcome this, researchers have invented a "biospleen", a device similar to a dialysis machine that makes use of magnetic nanobeads measuring 128 nanometres in diameter (one-five hundredths the width of a single human hair) coated with mannose-binding lectin (MBL), a type of genetically engineered human blood protein. -
$10 Bet Brings Researchers Closer to Industrial Scale Graphene Production
AaronW writes: After trying and failing to convince Nina Kovtyukhona to test her technique of separating layers of graphite and boron nitride to instead try graphene, Thomas E. Mallouk made a bet with Nina that her technique method would work. If it worked, Nina would owe him $10. If it didn't, he would owe her $100. The result was published in Nature yesterday (abstract). Thomas is $10 richer, and we are a step closer to industrial scale graphene production. -
Study: Antarctic Sea-Level Rising Faster Than Global Rate
An anonymous reader writes with this bit of good news for everyone who is waiting for their homes to one day be on the beach. Melting ice is fuelling sea-level rise around the coast of Antarctica, a new report in Nature Geoscience finds. Near-shore waters went up by about 2mm per year more than the general trend for the Southern Ocean as a whole in the period between 1992 and 2011. Scientists say the melting of glaciers and the thinning of ice shelves are dumping 350 billion tonnes of additional water into the sea annually. This influx is warming and freshening the ocean, pushing up its surface. "Freshwater is less dense than salt water and so in regions where an excess of freshwater has accumulated we expect a localized rise in sea level," explained Dr Craig Rye from the University of Southampton, UK, and lead author on the new journal paper. -
Underground Experiment Confirms Fusion Powers the Sun
sciencehabit writes: Scientists have long believed that the power of the sun comes largely from the fusion of protons into helium, but now they can finally prove it (abstract). An international team of researchers using a detector buried deep below the mountains of central Italy has detected neutrinos—ghostly particles that interact only very reluctantly with matter—streaming from the heart of the sun. Other solar neutrinos have been detected before, but these particular ones come from the key proton-proton fusion reaction that is the first part of a chain of reactions that provides 99% of the sun's power. -
Scientists Craft Seamless 2D Semiconductor Junctions
vinces99 (2792707) writes Scientists have developed what they believe is the thinnest-possible semiconductor, a new class of nanoscale materials made in sheets only three atoms thick. The University of Washington researchers have demonstrated that two of these single-layer semiconductor materials can be connected in an atomically seamless fashion known as a heterojunction. This result could be the basis for next-generation flexible and transparent computing, better light-emitting diodes, or LEDs, and solar technologies.
"Heterojunctions are fundamental elements of electronic and photonic devices," said senior author Xiaodong Xu, a UW assistant professor of materials science and engineering and of physics. "Our experimental demonstration of such junctions between two-dimensional materials should enable new kinds of transistors, LEDs, nanolasers, and solar cells to be developed for highly integrated electronic and optical circuits within a single atomic plane." -
Whole Organ Grown In Animal For First Time
An anonymous reader writes British scientists have produced the first working organ grown from scratch in a living animal. Reprogrammed cells created in a lab were used in a mouse to produce a thymus. The organ was created using connective tissue cells from a mouse embryo and were converted into a different cell strain by changing a genetic switch in their DNA. The resulting cells grew into the whole organ after being injected. It has only been tested on mice so far, but researchers at Edinburgh University say that within a decade the procedure could be effective and safe enough for humans. The findings were published in Nature Cell Biology. -
New Research Suggests Cancer May Be an Intrinsic Property of Cells
cranky_chemist sends this report from NPR: "Cancer simply may be here to stay. Researchers at Kiel University, the Catholic University of Croatia and other institutions discovered that hydra — tiny, coral-like polyps that emerged hundreds of millions of years ago — form tumors similar to those found in humans. Which suggests that our cells' ability to develop cancer is "an intrinsic property" that has evolved at least since then — way, way, way before we rallied our forces to try to tackle it, said Thomas Bosch, an evolutionary biologist at Kiel University who led the study, published in Nature Communications in June (abstract) To get ahead of cancer, he said, "you have to interfere with fundamental pathways. It's a web of interactions," he said. "It's very difficult to do." That's why cancer "will probably never be completely eradicated." -
Experimental Drug Stops Ebola-like Infection
sciencehabit writes: An experimental treatment against an Ebola-related virus can protect monkeys even when given up to 3 days after infection, the point at which they show the first signs of disease. The virus, known as Marburg, causes severe hemorrhagic fever—vomiting, diarrhea, and internal bleeding. In one outbreak, it killed 90% of people it infected. There are no proven treatments or vaccines against it. The new results raise hopes that the treatment might be useful for human patients even if they don't receive it until well after infection. The company that makes the compound, Tekmira, based in Burnaby, Canada, has started a human safety trial of a related drug to treat Ebola virus disease, and researchers hope that it, too, might offer protection even after a patient has started to feel ill. In other Ebola news, the two American aid workers who were infected with the virus while in Liberia have now recovered and been released from the hospital. -
How To Read a Microbiome Study Like a Scientist
bmahersciwriter (2955569) writes Scientific reports have increasingly linked the bacteria in your gut to health and maladies, often making wild-sounding claims. Did you hear about the mice who were given fecal transplants from skinny humans and totally got skinny! Well, some of the more gut-busting results might not be as solid as they seem. Epidemiologist Bill Hanage offers five critical questions to ask when confronted by the latest microbiome research. -
Processors and the Limits of Physics
An anonymous reader writes: As our CPU cores have packed more and more transistors into increasingly tiny spaces, we've run into problems with power, heat, and diminishing returns. Chip manufacturers have been working around these problems, but at some point, we're going to run into hard physical limits that we can't sidestep. Igor Markov from the University of Michigan has published a paper in Nature (abstract) laying out the limits we'll soon have to face. "Markov focuses on two issues he sees as the largest limits: energy and communication. The power consumption issue comes from the fact that the amount of energy used by existing circuit technology does not shrink in a way that's proportional to their shrinking physical dimensions. The primary result of this issue has been that lots of effort has been put into making sure that parts of the chip get shut down when they're not in use. But at the rate this is happening, the majority of a chip will have to be kept inactive at any given time, creating what Markov terms 'dark silicon.' Power use is proportional to the chip's operating voltage, and transistors simply cannot operate below a 200 milli-Volt level. ... The energy use issue is related to communication, in that most of the physical volume of a chip, and most of its energy consumption, is spent getting different areas to communicate with each other or with the rest of the computer. Here, we really are pushing physical limits. Even if signals in the chip were moving at the speed of light, a chip running above 5GHz wouldn't be able to transmit information from one side of the chip to the other."