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Decades-old Scientific Paper May Hold Clues To Dark Matter

Soulskill posted about half an hour ago | from the how-scientists-become-hoarders dept.

Science 22

sciencehabit writes: Here's one reason libraries hang on to old science journals: A paper from an experiment conducted 32 years ago may shed light on the nature of dark matter, the mysterious stuff whose gravity appears to keep the galaxies from flying apart. The old data put a crimp in the newfangled concept of a 'dark photon' and suggest that a simple bargain-basement experiment could put the idea to the test. The data come from E137, a "beam dump" experiment that ran from 1980 to 1982 at SLAC National Accelerator Laboratory in Menlo Park, California. In the experiment, physicists slammed a beam of high-energy electrons, left over from other experiments, into an aluminum target to see what would come out. Researchers placed a detector 383 meters behind the target, on the other side of a sandstone hill 179 meters thick that blocked any ordinary particles.

Stem Cells Grown From Patient's Arm Used To Replace Retina

Soulskill posted 4 hours ago | from the you-and-what-arm-eye dept.

Medicine 35

BarbaraHudson writes: The Globe and Mail is reporting the success of a procedure to implant a replacement retina grown from cells from the patient's skin. Quoting: "Transplant doctors are stepping gingerly into a new world, one month after a Japanese woman received the first-ever tissue transplant using stem cells that came from her own skin, not an embryo. On Sept. 12, doctors in a Kobe hospital replaced the retina of a 70-year-old woman suffering from macular degeneration, the leading cause of blindness in the developed world. The otherwise routine surgery was radical because scientists had grown the replacement retina in a petri dish, using skin scraped from the patient's arm.

The Japanese woman is fine and her retinal implant remains in place. Researchers around the world are now hoping to test other stem-cell-derived tissues in therapy. Dr. Jeanne Loring from the Scripps Research Institute in La Jolla, Calif., expects to get approval within a few years to see whether neurons derived from stem cells can be used to treat Parkinson's disease."

Detritus From Cancer Cells May Infect Healthy Cells

samzenpus posted 4 hours ago | from the one-bad-cell dept.

Medicine 27

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.

NY Doctor Recently Back From West Africa Tests Positive For Ebola

samzenpus posted 12 hours ago | from the I-think-I-saw-this-movie dept.

Medicine 284

An anonymous reader writes An emergency room doctor who recently returned to the city after treating Ebola patients in West Africa has tested positive for the virus, Mayor Bill de Blasio said. It's the first case in the city and the fourth in the nation. From the article: "The doctor, identified as Craig Spencer, 33, came back from treating Ebola patients in Guinea about 10 days ago, and developed a fever, nausea, pain and fatigue Wednesday night. The physician, employed at New York's Columbia Presbyterian Hospital, has been in isolation at Bellevue Hospital in Manhattan since Thursday morning, the official said."

Leaked Documents Reveal Behind-the-Scenes Ebola Vaccine Issues

timothy posted yesterday | from the how-much-for-what-benefit-to-whom-with-what-certainty dept.

Medicine 104

sciencehabit writes Extensive background documents from a meeting that took place today at the World Health Organization (WHO) have provided new details about exactly what it will take to test, produce, and bankroll Ebola vaccines, which could be a potential game changer in the epidemic. ScienceInsider obtained materials that vaccinemakers, governments, and WHO provided to the 100 or so participants at a meeting on 'access and financing' of Ebola vaccines. The documents put hard numbers on what until now have been somewhat fuzzy academic discussions. And they make clear to the attendees—who include representatives from governments, industry, philanthropies, and nongovernmental organizations—that although testing and production are moving forward at record speed, knotty issues remain.

Oldest Human Genome Reveals When Our Ancestors Mixed With Neanderthals

samzenpus posted 2 days ago | from the how-you-doing? dept.

Science 120

sciencehabit writes DNA recovered from a femur bone in Siberia belongs to a man who lived 45,000 years ago, according to a new study. His DNA was so well preserved that scientists were able to sequence his entire genome, making his the oldest complete modern human genome on record. Like present-day Europeans and Asians, the man has about 2% Neanderthal DNA. But his Neanderthal genes are clumped together in long strings, as opposed to chopped up into fragments, indicating that he lived not long after the two groups swapped genetic material. The man likely lived 7000 to 13,000 years after modern humans and Neanderthals mated, dating the mixing to 52,000 to 58,000 years ago, the researchers conclude. That's a much smaller window than the previous best estimate of 37,000 to 86,000 years ago.

Two Exocomet Families Found Around Baby Star System

samzenpus posted 2 days ago | from the across-the-universe dept.

Space 22

astroengine writes Scientists have found two families of comets in the developing Beta Pictoris star system, located about 64 light-years from Earth, including one group that appears to be remnants of a smashed-up protoplanet. The discovery bolsters our theoretical understanding of the violent processes that led to the formation of Earth and the other terrestrial planets in the solar system. "If you look back at the solar system when it was only 22 million years old, you might have seen phenomena that's a like more like what's happening in Beta Pic," astrophysicist Aki Roberge, with NASA Goddard Space Flight Center, Greenbelt, Md., told Discovery News.

6,000 Year Old Temple Unearthed In Ukraine

timothy posted 2 days ago | from the imagine-the-sound-track dept.

Science 107

An anonymous reader writes A massive archaeological dig of an ancient Ukrainian village first begun in 2009 has yielded a discovery that I sort of hope ends up inspiring a video game: a massive, scary-sounding temple. From the article: "Inside the temple, archaeologists found the remains of eight clay platforms, which may have been used as altars, the finds suggested. A platform on the upper floor contains "numerous burnt bones of lamb, associated with sacrifice," write Burdo and Videiko, of the Institute of Archaeology of the National Academy of Sciences of Ukraine. The floors and walls of all five rooms on the upper floor were "decorated by red paint, which created [a] ceremonial atmosphere."
Maybe this is what Putin has been after.

Astronomers Find Brightest Pulsar Ever Observed

Soulskill posted 2 days ago | from the go-big-or-go-home dept.

Space 68

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.

What It Took For SpaceX To Become a Serious Space Company

Soulskill posted 2 days ago | from the gumption-and-elbow-grease-(and-piles-of-cash) dept.

Space 95

An anonymous reader writes: The Atlantic has a nice profile of SpaceX's rise to prominence — how a private startup managed to successfully compete with industry giants like Boeing in just a decade of existence. "Regardless of its inspirations, the company was forced to adopt a prosaic initial goal: Make a rocket at least 10 times cheaper than is possible today. Until it can do that, neither flowers nor people can go to Mars with any economy. With rocket technology, Musk has said, "you're really left with one key parameter against which technology improvements must be judged, and that's cost." SpaceX currently charges $61.2 million per launch. Its cost-per-kilogram of cargo to low-earth orbit, $4,653, is far less than the $14,000 to $39,000 offered by its chief American competitor, the United Launch Alliance. Other providers often charge $250 to $400 million per launch; NASA pays Russia $70 million per astronaut to hitch a ride on its three-person Soyuz spacecraft. SpaceX's costs are still nowhere near low enough to change the economics of space as Musk and his investors envision, but they have a plan to do so (of which more later)."

DHS Investigates 24 Potentially Lethal IoT Medical Devices

Soulskill posted 2 days ago | from the but-they're-fine-with-mcdonald's-so-don't-get-your-hopes-up dept.

Medicine 78

An anonymous reader writes: In the wake of the U.S. Food and Drug Administration's recent recommendations to strengthen security on net-connected medical devices, the Department of Homeland Security is launching an investigation into 24 cases of potential cybersecurity vulnerabilities in hospital equipment and personal medical devices. Independent security researcher Billy Rios submitted proof-of-concept evidence to the FDA indicating that it would be possible for a hacker to force infusion pumps to fatally overdose a patient. Though the complete range of devices under investigation has not been disclosed, it is reported that one of them is an "implantable heart device." William Maisel, chief scientist at the FDA's Center for Devices and Radiological Health, said, "The conventional wisdom in the past was that products only had to be protected from unintentional threats. Now they also have to be protected from intentional threats too."

First Evidence of Extrasolar Planets Discovered In 1917

Soulskill posted 2 days ago | from the but-who's-counting dept.

Space 58

KentuckyFC writes: Earth's closest white dwarf is called van Maanen 2 and sits 14 light-years from here. It was discovered by the Dutch astronomer Adriaan van Maanen in 1917, but it was initially hard to classify. That's because its spectra contains lots of heavy elements alongside hydrogen and helium, the usual components of a white dwarf photosphere. In recent years, astronomers have discovered many white dwarfs with similar spectra and shown that the heavy elements come from asteroids raining down onto the surface of the stars. It turns out that all these white dwarfs are orbited by a large planet and an asteroid belt. As the planet orbits, it perturbs the rocky belt, causing asteroids to collide and spiral in toward their parent star. This process is so common that astronomers now use the heavy element spectra as a marker for the presence of extrasolar planets. A re-analysis of van Maanen's work shows that, in hindsight, he was the first to discover the tell-tale signature of extrasolar planets almost a century ago.

Fiber Optics In Antarctica Will Monitor Ice Sheet Melting

Soulskill posted 2 days ago | from the won't-somebody-think-of-the-penguins dept.

Science 80

sciencehabit writes: Earth is rapidly being wired with fiber-optic cables — inexpensive, flexible strands of silicon dioxide that have revolutionized telecommunications. They've already crisscrossed the planet's oceans, linking every continent but one: Antarctica. Now, fiber optics has arrived at the continent, but to measure ice sheet temperatures rather than carry telecommunication signals. A team of scientists using an innovative fiber-optic cable–based technology has measured temperature changes within and below the ice over 14 months. This technology, they say, offers a powerful new tool to observe and quantify melting at the base of the West Antarctic Ice Sheet.

Ebola Does Not Require an "Ebola Czar," Nor Calling Up the National Guard

Soulskill posted 2 days ago | from the only-thing-we-have-to-fear-is-fear-itself-and-liquefied-organs dept.

Medicine 380

Lasrick writes: David Ropeik explores risk-perception psychology and Ebola in the U.S. "[O]fficials are up against the inherently emotional and instinctive nature of risk-perception psychology. Pioneering research on this subject by Paul Slovic, Baruch Fischhoff, and others, vast research on human cognition by Daniel Kahneman and colleagues, and research on the brain's fear response by neuroscientists Joseph LeDoux, Elizabeth Phelps, and others, all make abundantly clear that the perception of risk is not simply a matter of the facts, but more a matter of how those facts feel. ... People worry more about risks that are new and unfamiliar. People worry more about risks that cause greater pain and suffering. People worry more about threats against which we feel powerless, like a disease for which there is no vaccine and which has a high fatality rate if you get it. And people worry more about threats the more available they are to their consciousness—that is, the more aware people are of them."

Cell Transplant Allows Paralyzed Man To Walk

Soulskill posted 2 days ago | from the saved-by-a-nose dept.

Medicine 161

New submitter tiberus sends word of a breakthrough medical treatment that has restored the ability to walk to a man who was paralyzed from the chest down after his spinal cord was severed in a knife attack. A research team from the UK, led by Professor Geoff Raisman, transplanted cells from the patient's nose, along with strips of nerve tissue from his ankle, to the place where the spine was severed. This allowed the fibers in the spinal cord to gradually reconnect. The treatment used olfactory ensheathing cells (OECs) - specialist cells that form part of the sense of smell. ... In the first of two operations, surgeons removed one of the patient's olfactory bulbs and grew the cells in culture. Two weeks later they transplanted the OECs into the spinal cord, which had been cut through in the knife attack apart from a thin strip of scar tissue on the right. They had just a drop of material to work with - about 500,000 cells. About 100 micro-injections of OECs were made above and below the injury. Four thin strips of nerve tissue were taken from the patient's ankle and placed across an 8mm (0.3in) gap on the left side of the cord. ... Two years after the treatment, he can now walk outside the rehabilitation center using a frame.

Mars Orbiter Beams Back Images of Comet's Surprisingly Tiny Nucleus

timothy posted 3 days ago | from the knowledge-through-correction dept.

Space 47

astroengine writes The High-Resolution Imaging Science Experiment (HiRISE) camera on board NASA's Mars Reconnaissance Orbiter (MRO) has become the first instrument orbiting Mars to beam back images of comet Siding Spring's nucleus and coma. And by default, it has also become the first ever mission to photograph a long-period comet's pristine nucleus on its first foray into the inner solar system. Interestingly, through analysis of these first HiRISE observations, astronomers have determined that the icy nucleus at the comet's core is much smaller than originally thought. "Telescopic observers had modeled the size of the nucleus as about half a mile, or one kilometer, wide," writes a NASA Jet Propulsion Laboratory news release. "However, the best HiRISE images show only two to three pixels across the brightest feature, probably the nucleus, suggesting a size less than half that estimate."

Australian Physicists Build Reversible Tractor Beam

Soulskill posted 3 days ago | from the take-that-wesley dept.

Science 70

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."

A Look At Orion's Launch Abort System

Soulskill posted 3 days ago | from the for-really-bad-days dept.

NASA 43

An anonymous reader writes: With the construction of Orion, NASA's new manned spacecraft, comes the creation of a new Launch Abort System — the part of the vehicle that will get future astronauts back to Earth safely if there's a problem at launch. The Planetary Society's Jason Davis describes it: "When Orion reaches the apex of its abort flight, it is allowed to make its 180-degree flip. The capsule of astronauts, who have already realized they will not go to space today, experience a brief moment of weightlessness before the capsule starts falling back to Earth, heat shield down. The jettison motor fires, pulling the LAS away from Orion. ... Orion, meanwhile, sheds its Forward Bay Cover, a ring at the top of the capsule protecting the parachutes. Two drogue chutes deploy, stabilizing the wobbling capsule. The drogues pull out Orion's three main chutes, no doubt eliciting a sigh of relief from the spacecraft's occupants."

NASA's HI-SEAS Project Results Suggests a Women-Only Mars Crew

timothy posted 3 days ago | from the couple-of-jockeys-too dept.

Mars 394

globaljustin writes "Alan Drysdale, a systems analyst in advanced life support and a contractor with NASA concluded, "Small women haven't been demonstrated to be appreciably dumber than big women or big men, so there's no reason to choose larger people for a flight crew when it's brain power you want," says Drysdale. "The logical thing to do is to fly small women." Kate Greene, who wrote the linked article, took part in the first HI-SEAS experiment in Martian-style living, and has some compelling reasons for an all-women crew, energy efficiency chief among them: Week in and week out, the three female crew members expended less than half the calories of the three male crew members. Less than half! We were all exercising roughly the same amount—at least 45 minutes a day for five consecutive days a week—but our metabolic furnaces were calibrated in radically different ways. During one week, the most metabolically active male burned an average of 3,450 calories per day, while the least metabolically active female expended 1,475 calories per day. It was rare for a woman on crew to burn 2,000 calories in a day and common for male crew members to exceed 3,000. ... The calorie requirements of an astronaut matter significantly when planning a mission. The more food a person needs to maintain her weight on a long space journey, the more food should launch with her. The more food launched, the heavier the payload. The heavier the payload, the more fuel required to blast it into orbit and beyond. The more fuel required, the heavier the rocket becomes, which it in turn requires more fuel to launch.

An Algorithm to End the Lines for Ice at Burning Man

timothy posted 3 days ago | from the that-trick's-not-so-weird dept.

Businesses 337

Any gathering of 65,000 people in the desert is going to require some major infrastructure to maintain health and sanity. At Burning Man, some of that infrastructure is devoted to a supply chain for ice. Writes Bennett Haselton, The lines for ice bags at Burning Man could be cut from an hour long at peak times, to about five minutes, by making one small... Well, read the description below of how they do things now, and see if the same suggested change occurs to you. I'm curious whether it's the kind of idea that is more obvious to students of computer science who think algorithmically, or if it's something that could occur to anyone. Read on for the rest; Bennett's idea for better triage may bring to mind a lot of other queuing situations and ways that time spent waiting in line could be more efficiently employed.

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