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New DNA Method Makes It Easier To Trace CriminalsDNA samples often convict criminals. But many of today's forensic tests are so polluted by soil, tobacco and food remains, for example, that they can not be used. Now researchers in Sweden have improved a critical part of the analysis process. The first findings indicate that the new method strengthens the DNA analysis so that previously negative samples yield positive and usable DNA profiles.Source: ScienceDaily: Latest Science News | 31 Oct 2009 | 9:00 am Stress-induced Changes In Brain Circuitry Linked To Cocaine RelapseStress-evoked changes in circuits that regulate serotonin in certain parts of the brain can precipitate a low mood and a relapse of cocaine-seeking, based on mouse studies.Source: ScienceDaily: Latest Science News | 31 Oct 2009 | 9:00 am High-definition Colonoscopy Detects More Polyps, Researchers SayHigh-definition colonoscopy is much more sensitive than standard colonoscopy in finding polyps that could morph into cancer, say researchers.Source: ScienceDaily: Latest Science News | 31 Oct 2009 | 9:00 am Major Advance In Human Antibody Therapy Against Deadly Nipah VirusScientists report a major step forward in the development of an effective therapy against two deadly viruses, Nipah virus and the related Hendra virus.Source: ScienceDaily: Latest Science News | 31 Oct 2009 | 9:00 am Donor Race May Impact Kidney Transplant SurvivalThe race of kidney donors may affect the survival rates of transplant recipients, according to a new study.Source: ScienceDaily: Latest Science News | 31 Oct 2009 | 9:00 am New Analyses Of Dinosaur Growth May Wipe Out One-third Of SpeciesPaleontologists Mark Goodwin and Jack Horner have dug for 11 years in Montana's Hell Creek Formation in search of every dinosaur fossil they can find, accumulating specimens of all stages of development. Their new report on the growth stages of dome-headed dinosaurs shows that two named species are really just young pachycephalosaurs. They say that perhaps one-third of all named dinosaurs may not be separate species, but juvenile or subadult stages of other known dinosaurs.Source: ScienceDaily: Latest Science News | 31 Oct 2009 | 9:00 am Sacked adviser criticises BrownThe UK's former chief drugs adviser has accused the prime minister of reclassifying cannabis for political reasons.Source: BBC News | Science & Environment | UK Edition | 31 Oct 2009 | 3:57 am Progress Made On Group B Streptococcus VaccineScientists have completed a phase II clinical study that indicates a vaccine to prevent Group B Streptococcus infection is possible.Source: ScienceDaily: Latest Science News | 31 Oct 2009 | 3:00 am Placental Precursor Stem Cells Require Testosterone-free Environment To SurviveTrophoblast stem cells, found in the layer of peripheral embryonic stem cells from which the placenta is formed, are thought to exhibit "immune privilege" that aids cell survivability and is potentially beneficial for cell and gene therapies. Survivability of TSCs has been thought to require the presence of ovarian hormones. This study, however, demonstrates that it is the absence of male hormones, rather than the presence of female hormones, that allows extended transplanted cell survivability.Source: ScienceDaily: Latest Science News | 31 Oct 2009 | 3:00 am Regeneration Can Be Achieved After Chronic Spinal Cord InjuryScientists report that regeneration of central nervous system axons can be achieved in rats even when treatment delayed is more than a year after the original spinal cord injury.Source: ScienceDaily: Latest Science News | 31 Oct 2009 | 3:00 am Interactions With Aerosols Boost Warming Potential Of Some GasesFor decades, climate scientists have worked to identify and measure key substances -- notably greenhouse gases and aerosol particles -- that affect Earth's climate. And they've been aided by ever more sophisticated computer models that make estimating the relative impact of each type of pollutant more reliable. Yet the complexity of nature -- and the models used to quantify it -- continues to serve up surprises. The most recent? Certain gases that cause warming are so closely linked with the production of aerosols that the emissions of one type of pollutant can indirectly affect the quantity of the other. And for two key gases that cause warming, these so-called "gas-aerosol interactions" can amplify their impact.Source: ScienceDaily: Latest Science News | 31 Oct 2009 | 3:00 am 'I hate whale meat,' Japan's PM confides: report (AFP)
Source: Yahoo! News: Science News | 31 Oct 2009 | 1:08 am Mixed messages as Europe reaches out on climate (AFP)
Source: Yahoo! News: Science News | 30 Oct 2009 | 11:57 pm Typhoon smashes storm-weary Philippines (AFP)
Source: Yahoo! News: Science News | 30 Oct 2009 | 11:35 pm Mars Rover Spirit Has Amnesia Again (SPACE.com)SPACE.com - NASA's Mars rover Spirit is suffering a new bout of amnesia, one that comes after months of being stuck in deep Martian sand.Source: Yahoo! News: Science News | 30 Oct 2009 | 10:42 pm Oldest Known Spider Webs Discovered (LiveScience.com)LiveScience.com - Silken spider webs dating back some 140 million years have been discovered preserved in amber, scientists announce today.Source: Yahoo! News: Science News | 30 Oct 2009 | 6:15 pm English wine gets a helping hand... from SpaceEnglish vineyards have signed up to use a harvest optimisation scheme based on data gathered from satellites.Source: BBC News | Science & Environment | UK Edition | 30 Oct 2009 | 6:13 pm Oldest Known Spider Webs DiscoveredScientists discover ancient silken threads from a spider web embalmed in amber.Source: Livescience.com | 30 Oct 2009 | 6:04 pm Ecosmackdown: Pets Versus Solar Panels
It takes 17 times more land to feed American pets than would be required by solar farms producing enough electricity to meet all the demand in the United States. Why do we know this? A new book by Robert and Brenda Vale, two architects at Victoria University of Wellington in New Zealand, looked into the ecological foodprints of the world’s pets, New Scientist reported. By examining the land and resources necessary to produce the meat and grains that compose pet food they discovered something startling: It takes over 90,000 square feet of land (that’s two whole acres) to feed a medium-sized dog and 16,000 square feet of land to feed a cat. The Humane Society estimates Americans own about 75 million dogs and 88 million cats. We did the math and found that feeding those animals takes about 294 thousand square miles of land. That’s a little bigger than Texas! That got us thinking because a default criticism of solar power has been to attack the amount of land it requires relative to nuclear or fossil fuel plants. Disingenuous or not, the idea that solar takes up too much land is widespread. For example, Senator Lamar Alexander, R-Tenn., a long-time nuclear supporter, decried “energy sprawl” in a Wall Street Journal editorial last month. The amount of land required to generate electricity for the nation does sound like an awful lot, sometimes. One recent calculation led by Vasilis M. Fthenakis, an environmental engineer at Columbia University’s Center for Life Cycle Analysis, found that it would take covering 16,602 square miles[pdf] of land in the southwestern desert with solar energy converters like cadmium telluride photovoltaic panels to generate the 3,816,000,000 megawatt-hours of electricity that is used in the U.S. ever year. (Other estimates have found smaller solar land needs.) That’s why it’s important to compare solar’s land requirements with other American practices. Multiply anything by the scale of the United States and the numbers start to sound absurdly big. When feeding our pets takes 17 times more land than feeding our supposedly rapacious electricity demand, it’s difficult to argue that energy sprawl, for solar, is a major problem. See Also:
WiSci 2.0: Alexis Madrigal’s Twitter, Google Reader feed, and green tech history research site; Wired Science on Twitter and Facebook.
Source: Wired: Wired Science | 30 Oct 2009 | 5:32 pm Pollution Trips Up Female Marathon RunnersAverage marathon times of female runners suffered in cities with higher pollution levels.Source: Discovery News Top Stories : Discovery Channel | 30 Oct 2009 | 4:30 pm Missing Amazon plane makes river landing, 9 alive (AP)AP - A plane that went missing over the Amazon made an emergency river landing in a remote part of the rain forest and nine of the 11 people aboard survived, the Brazilian air force said Friday.Source: Yahoo! News: Science News | 30 Oct 2009 | 4:22 pm TIMELINE: Brief History of the InternetExplore what led to the most advanced communications network in human history.Source: Discovery News Top Stories : Discovery Channel | 30 Oct 2009 | 4:15 pm Divers probe Mayan ruins submerged in Guatemala lakeGUATEMALA CITY (Reuters) - Scuba divers are exploring the depths of a volcanic lake in Guatemala to find clues about an ancient sacred island where Mayan pilgrims flocked to worship before it was submerged by rising waters.Source: Reuters: Science News | 30 Oct 2009 | 4:02 pm First Japanese Cargo Ship Leaves Space Station (SPACE.com)SPACE.com - Japan's first unmanned space cargo ship cast off from the International Space Station Friday as it nears the end of a successful maiden voyage.Source: Yahoo! News: Science News | 30 Oct 2009 | 3:17 pm Disappearing FrogsDisease, pollution, and loss of habitat are killing off hundreds of species of amphibians. One of the biggest threats right now is an aquatic fungus called chytrid that infects the skin of these historically tough, resilient creatures.Source: Livescience.com | 30 Oct 2009 | 2:28 pm Amgen, Amerisource sued over drug kickback scheme (Reuters)Reuters - Biotechnology giant Amgen Inc and drug wholesaler AmerisourceBergen Corp were sued on Friday by 14 U.S. states and the District of Columbia over an alleged kickback scheme designed to boost sales of Amgen's popular anemia drug, Aranesp.Source: Yahoo! News: Science News | 30 Oct 2009 | 2:19 pm Bats Find Fellatio BeneficialHumans and primates aren't the only ones to experiment with oral sex. Bats do it too.Source: Livescience.com | 30 Oct 2009 | 2:04 pm Genes may explain why churchgoers are teetotalers (Reuters)Reuters - Churchgoers have been found to have lower rates of drinking and smoking than those who spend their Sundays elsewhere. Now a new study suggests that for adults, it may not be church attendance itself that explains much of the phenomenon. It might be genes.Source: Yahoo! News: Science News | 30 Oct 2009 | 2:02 pm EU strikes climate funding dealEU leaders agree a conditional deal to help other nations fight global warming, ahead of the Copenhagen climate summit.Source: BBC News | Science & Environment | UK Edition | 30 Oct 2009 | 2:02 pm What Bats DoAn explicit video of a male and female bat was produced by researchers who discovered the behavior. The female (front) is bending over to perform fellatio during copulation.Source: Livescience.com | 30 Oct 2009 | 1:44 pm BP hit with record US fine for safety violations (AFP)
Source: Yahoo! News: Science News | 30 Oct 2009 | 1:41 pm Rocket booster damaged on returnThe booster used on the Ares 1-X test rocket on Wednesday was damaged when it fell back into the ocean, Nasa says.Source: BBC News | Science & Environment | UK Edition | 30 Oct 2009 | 12:55 pm BLOG: Kepler's Exoplanet Hunt DelayedThe orbital Earth-like exoplanet hunter will be in a holding pattern until 2011.Source: Discovery News Top Stories : Discovery Channel | 30 Oct 2009 | 12:20 pm QUIZ: Daylight Savings TimeTest your knowledge on Daylight Savings Time: What it is, its scope and history.Source: Discovery News Top Stories : Discovery Channel | 30 Oct 2009 | 12:20 pm As Bats Begin Hibernation, Deaths ExpectedA mysterious syndrome is expected to continue afflicting bats this winter.Source: Discovery News Top Stories : Discovery Channel | 30 Oct 2009 | 12:15 pm New Dinosaur Built Like a Sherman TankA newfound dinosaur was the paleo version of an armored tank.Source: Livescience.com | 30 Oct 2009 | 12:09 pm Scent of Fear Keeps Male Bed Bugs From Mating With Each Other
Male bed bugs get confused in bed. Now a scientist has found a bug chemical signal that translates, “Whoa, buddy. I’m a guy too.”
At first contact, sex recognition for these insects works largely by trial and error, Ryne says. What corrects those errors, she has found, is a blend of chemicals that earlier work has also described as the bed bug alarm pheromone. “This is the first time to my knowledge that anyone has shown that alarm pheromones are used for sexual recognition,” Ryne says. Females can release the substance when disturbed but typically don’t when grasped by a male, Ryne says. But males do exude the scent when grabbed by another male. After a whiff of the stuff, misguided suitors back off, Ryne reports online October 24 in Animal Behaviour.
Pheromones may have achieved their fame in popular culture as dizzying lures for the opposite sex, but biologists have discovered plenty of other kinds of pheromones. Compounds can fuel aggression among male mice or urge baby rabbits to search for a nipple. Bed bugs release the pheromone blend of the small, volatile molecules (E)-2-octenal and (E)-2-hexenal when disturbed, Ryne says. A mating attempt might indeed be disturbing, since males deliver their sperm by what’s called traumatic insemination. They ignore the opening to the female reproductive tract and inject sperm with a needlelike appendage directly through the outer covering of a mate’s body. In the abdominal area most commonly pierced, female bed bugs grow a mass of the kinds of cells associated with immune defense. Males, though, have no extra protection there. To test the idea that the alarm pheromone helps mistakenly targeted males free themselves, Ryne painted nail polish over the glands that produce the substance, thus blocking its release. Males that couldn’t signal chemically ended up in longer embraces than males dabbed elsewhere with nail polish. For a different test, Ryne collected the substance by washing disturbed males with a solvent. When she applied wafted the extract over mating pairs of males and females, the males backed off. The finding showed that even in the presence of a suitable mate, the signal disturbed the males, she says. Ryne herself can smell the pheromone, she says. It’s a bit like almond, but not particularly pleasant. “Older people say that you used to be able to tell whose house had bed bugs because it had a peculiar smell,” she says. Images: 1) A male and femal bed bud mate. 2) A bed bug feeding on blood from a person. Rickard Ignell/Swedish University of Agricultural Sciences See Also:
Source: Wired: Wired Science | 30 Oct 2009 | 11:47 am Short Heels and Long Toes: A Surprising Recipe for Speed
Track coaches have long claimed that the best sprinters are born, not made. Now, new research on the biomechanics of sprinting suggests that at least part of elite athletes’ impressive speed comes from the natural shape of their foot and ankle bones. Using ultrasound imaging, researchers compared the feet of 12 top college sprinters with those of 12 mere mortals. Surprisingly, the athletes had particularly short heels and longer-than-average toes — features that actually put them at a mechanical disadvantage when running. “What we found is that sprinters actually had less mechanical advantage than the non-sprinter subjects that we tested,” said biomechanics researcher Stephen Piazza of Penn State University, co-author of the study published Friday in the Journal of Experimental Biology. “This was surprising to us because we expected that sprinters needed all the help they could get.” Piazza and his co-author, kinesiology graduate student Sabrina Lee, launched their study after they happened to measure the Achilles’ tendon of a former NFL wide receiver, and were shocked by how little leverage his tendon provided.
Similarly, having a short “lever arm” on your Achilles tendon makes it harder to pull your foot off the ground — which is why the researchers were surprised to find short heels on a professional sprinter. But further research proved the football player wasn’t an aberration: On average, top sprinters had heels that were 25 percent shorter than their non-athlete counterparts, as well as significantly longer toes. To understand the paradox, the researchers set up a computer model of a sprinter’s push-off. The simulation revealed that despite providing a mechanical disadvantage, the short lever arm of a sprinter’s heel actually produced more force than the longer lever arm of a non-sprinter. “It turns out that there’s a trade-off that we think is going on,” Piazza said. “The larger the lever arm of the Achilles tendon, the more the tendon has to travel up when you point your toes. What that means is that the calf muscles have to shorten more rapidly, and muscle that is shortening more rapidly can’t generate much force.” In other words, sprinters sacrifice the mechanical advantage of a long lever for the benefit of a stronger push-off. Since quick acceleration over a short distance is the key to winning a short race, Piazza says the trade-off makes sense for sprinters. “He has to be able to generate a lot of force, but he also needs that leverage,” he said. “It turns out that by giving up some leverage, you actually gain more in terms of force generation and get a net benefit.” According to the computer simulation, having long toes also makes sprinters speedier, by extending the time that a runner’s foot makes contact with the ground. “Early in the race, the only way you have to speed up is through interaction with the ground,” Piazza said. “If you want to speed up quickly, you need to have some meaningful interaction with the ground.” But like short heels, long toes come with a cost. Earlier this year, a group of anthropologists reported that long toes are less energetically economical for long-distance running. Led by evolution researcher Campbell Rolian of the University of Calgary, the group found that modern humans have much shorter toes than their early hominid ancestors, suggesting that the need for endurance probably superseded the need for speed and acceleration in our ancient relatives. “The two studies are actually nicely complementary, and show that long toes provide more power for propulsion, but that this comes at a cost of greater muscle effort,” Rolian wrote in an e-mail to Wired.com. “So there may be an optimal length at which you can get both a capacity to push off and some muscle economy.” Of course, without studying athletes over time, it’s impossible to know whether elite sprinters are born with short heels and long toes, or whether these beneficial features result from constant sprinting. “We usually think of the shapes of your bones as things that shouldn’t be changeable with time,” Piazza said. On the other hand, he points out that there are plenty of examples of diseases or activities that can gradually change how bones and tendons fit together, so it’s possible that intensive training could affect the shape of an athlete’s foot. “I’d love to do a longitudinal study to follow kids or athletes doing sprint training,” he said, “and see if there are changes in how their tendons attach on their bones.” Image 1: Michael Lokner/Flickr. Image 2: The Achilles tendon, from Gray’s Anatomy/Wikipedia Commons. See Also:
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Source: Wired: Wired Science | 30 Oct 2009 | 11:11 am BLOG: Ares Rocket Dented During SplashdownParachute problems cause the Ares I-X test rocket to fall faster than expected.Source: Discovery News Top Stories : Discovery Channel | 30 Oct 2009 | 9:45 am 3,000 Images Combine for Stunning Milky Way PortraitMilky Way panorama assembled from 3,000 individual photographs.Source: Livescience.com | 30 Oct 2009 | 9:41 am Superstitious Beliefs Cemented Before BirthPeople who believe in paranormal phenomena may have just been born that way.Source: Discovery News Top Stories : Discovery Channel | 30 Oct 2009 | 9:30 am Anthropology Abroad: Studying Women's Roles in the MilitaryMaggie Serrato traveled to South Korea to better understand the experiences of women in non-traditional roles.Source: Livescience.com | 30 Oct 2009 | 8:34 am Hybrid Cubs Show Polar Bear and Grizzly TraitsCubs born to polar bear and grizzly bear parents show mix of features.Source: Livescience.com | 30 Oct 2009 | 8:21 am Scientifically Haunted House Suggests You’re a Sucker
Fake blood, canned screams and plastic skeletons are fun, but if you want a real haunted house, turn to scientists.
To test whether it’s possible to artificially induce paranormal experiences — or, from a different perspective, to technologically summon a spirit — researchers at London’s Goldsmith College and architect Usman Haque designed a scientifically haunted room. They were inspired by earlier studies in which test subjects reported contact with the phantasmic when exposed to electromagnetic fields and waves of infrasound. This hasn’t just taken place in the laboratory. Odd EMF fields have been recorded at reputedly haunted castles. And geomagnetic flux caused by shifting tectonic plates reportedly produces surges in poltergeist sightings. Meanwhile, infrasound waves below the level of human hearing have been linked to visitation. Of course, ghosts — which 40 percent of the American public claim to believe in — are only one possible explanation. Perhaps people feel something, and what they call “haunting” is their uniquely sensitive power of perception. Maybe they’re just suggestible. So Christopher French, head of Goldsmith’s Anomalistic Psychology Research Unit and editor of the Skeptic magazine, built the haunted room: a white, wood-frame canvas tent 9 feet in diameter, located in the front room of a London row house. It was entirely featureless, but hidden speakers cast infrasound waves like those measured in supposedly-haunted Coventry Cathedral. Other speakers projected sound waves that produced an electromagnetic frequency used in laboratory stimulation of paranormal feeling. Each field’s range was focused in a different part of the room, and some areas were field-free. If haunting indeed had a wavelength, then people would ostensibly report unusual experiences in the target areas.
But there was a catch: The sensations had nothing to do with where they were standing in the room. When French’s team crunched the numbers, the only statistically significant association appeared in subjects who scored highly on a test of psychological predisposition to the sort of transcendental feelings generally experienced by epileptics with unstable temporal lobes. There are a few different ways of looking at these results, said French. “It might be that certain people are wired up in a particular way, and in the right environment, they actually are seeing something that’s objectively there, but others don’t have the ability to see,” he said. But while that can’t be ruled out, he thinks there’s a simpler explanation: People tend to think about what they’re told to. Asked to track strange feelings, they started noticing them. And the participants’ response rates indeed followed what’s predicted by models of suggestible behavior. “We did manage to build an artificially haunted room, but it wasn’t related to the environmental factors, but to suggestibility,” said French, who’d hoped for a firmer result. An EMF effect would have been exciting, and opened up new lines of investigation, he said. Of course, French still acknowledged that out-of-lab paranormal experiences could be real, or that his experimental waveforms may have failed to replicate those found naturally. He hopes to repleat the study using “a very different, very anomalous pattern of EMF activity” he recently recorded in Muncaster Castle, said to be one of the most haunted castles in the United Kingdom. As for whether he’d felt anything inside the haunted room, French admitted that he hadn’t spent much time there. “I went in and out when we were setting it up, but I didn’t even make myself a pilot participant,” he said. “Maybe I should have.” Images: Christopher French See Also:
Citation: “The “Haunt” project: An attempt to build a “haunted” room by manipulating complex electromagnetic fields and infrasound.” By Christopher C. French, Usman Haque, Rosie Bunton-Stasyshyn and Rob Davis. Cortex, Vol. 45, Issue 5, May 2009. Brandon Keim’s Twitter stream and reportorial outtakes; Wired Science on Twitter. Brandon is currently working on a book about ecosystem and planetary tipping points.
Source: Wired: Wired Science | 30 Oct 2009 | 8:18 am Top 10 Things that Make Humans SpecialWhat separates humans from other animals? Some of the answers might surprise you.Source: Livescience.com | 30 Oct 2009 | 7:37 am Gang Assaults: Why They HappenThe gang rape of a Calif. teen sheds light on a problem that sociologists say is too common.Source: Discovery News Top Stories : Discovery Channel | 30 Oct 2009 | 7:36 am Klondike Holds Clues to Ancient EnvironmentAlaska, Siberia and the Canadian Yukon remained ice-free during the ice age and was home to unique organisms.Source: Livescience.com | 30 Oct 2009 | 6:56 am Earth WatchThe magnetic attraction of climate 'scepticism'Source: BBC News | Science & Environment | UK Edition | 30 Oct 2009 | 6:53 am SLIDE SHOW: Halloween's HistoryTake a tour of Halloween's 2,000-year-old, bumpy history.Source: Discovery News Top Stories : Discovery Channel | 30 Oct 2009 | 5:56 am Fast Runners Have Shorter Heels, Longer ToesElite human sprinters have similar ankle structure to that of speedy animals.Source: Discovery News Top Stories : Discovery Channel | 30 Oct 2009 | 5:55 am Polar bear plus grizzly equals?A new study reveals what happens when a polar bear is crossed with a grizzly.Source: BBC News | Science & Environment | UK Edition | 30 Oct 2009 | 3:56 am Frog embryos 'smell' predatorsFrogs learn the smell of their future predators while they are still embryos.Source: BBC News | Science & Environment | UK Edition | 30 Oct 2009 | 3:16 am
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Considering that bed bugs are making a comeback as a pest in the industrialized world, “knowing how they mate is important,” says entomologist Joshua Benoit of Ohio State University in Columbus. He too has been studying the alarm pheromone, and he agrees that the bugs use it in several ways.
