Tuesday, 9 March 2010

Johnald's Fantastical Daily Link Splurge

Johnald's Fantastical Daily Link Splurge


Mile-High Mega-Kites Could Pull Giant, Floating Power-Plant Ships

Posted: 09 Mar 2010 10:36 AM PST

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Take a huge oceanic catamaran, stick a hydroelectric turbine underneath it, and hitch it to a 6.5 million-square-foot parafoil flying nearly a mile in the air. That's a Korean research team's new proposal for generating gigawatts of clean energy.

As the parafoil pulls the boat, seawater would be forced through the turbine, which generates electricity. The 800 megawatts of electricity produced would separate sea water into hydrogen and oxygen by electrolysis, and the hydrogen would then be stored on-board the ships.

windareas"The calculation shows that, with a large such ship, a gigawatt order electrical power may be harvested by this system," wrote Chul Park of the Korea Aerospace Research Insitute and Jongchul Kim of the Korea Advanced Institute of Science and Technology, in the journal Energy in March.

"If such ships are deployed at 20 km (12.4 mile) intervals over two temperate zones, one in the middle of the Pacific Ocean in the northern hemisphere and the other everywhere in the southern hemisphere, the total power produced will be many times that needed by the world," they wrote.

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The new system is a remarkable, if a bit wacky, synthesis of different lines of new energy R&D. Park and Kim rightly note that parafoils — large industrial-strength kites — are now used by the German company Skysails to reduce the fuel consumption of ocean-going vessels by up to 35 percent.

High-altitude wind power using similar parafoils has received increasing attention from entrepreneurs and green tech backers like Google.org because the higher you go, the better and steadier the winds are.

And small groups have been working on hydroelectric generators mounted to sailboats.

But it's fair to say that though the system is largely a recombination of things that are on the cusp of feasibility, nothing even remotely similar has been tried, or even suggested, by anyone. As such, the components such a plant would need are not currently manufactured. For example, the largest commercially available parafoil has an area of just 6,835 square feet, or about 945 times smaller than the wing the researchers propose.

The idea doesn't even have a catchy name yet. Perhaps it could be called the "hydro paraplant."

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"Wind power generation with a parawing on ships, a proposal" in Energy 35 (2010) 1425–1432 by J. Kim and C. Park

Images: 1. Skysails. 2-4. Kim and Park.

WiSci 2.0: Alexis Madrigal's Twitter, Tumblr, and green tech history research site; Wired Science on Twitter and Facebook.

Low Tolerance for Pain May Be Genetic

Posted: 08 Mar 2010 02:04 PM PST

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One form of a common genetic variant may ratchet up pain sensitivity in people who have it, researchers report online March 8 in the Proceedings of the National Academy of Sciences.

sciencenewsThe discovery could lead to more powerful pain treatments that lack the debilitating side effects of current drugs. "We could fill our clinics many times over with people with chronic pain that we can't help with our current medications," says neurologist and neuroscientist Stephen Waxman of Yale University School of Medicine and the Veterans Affairs Connecticut Hospital in West Haven.

In the new study, researchers led by clinical geneticist Geoffrey Woods of the Cambridge Institute for Medical Research in the United Kingdom examined the DNA of 578 people with the painful condition osteoarthritis. Woods and his colleagues searched for genetic variations that might be linked to how much pain a patient reported feeling — a subjective measure, Woods says, but currently the best researchers can do.

The team found that people who reported higher levels of pain were more likely to carry a particular DNA base, an A instead of a G, at a certain location in the gene SCN9A. The A version is found in an estimated 10 to 30 percent of people, Woods says, though its presence varies in populations of different ancestries.

This gene version may set the pain threshold, he says. "You're more sensitive to pain."

The same trend — higher pain levels reported by people who carried the A — held true in cohorts of people with other painful conditions including sciatica, phantom limb syndrome and lumbar discectomy. The A variant wasn't strongly associated with higher pain scores in patients with chronic pancreatitis, however. Woods says that might change as more people are added to the study.

The researchers also looked for the gene variant in 186 healthy women who had been assessed based on their responses to a number of painful stimuli. The women with the highest responses were more likely to have the A variant instead of the G.

The genetic variation affects the structure of a protein that sits on the outside of nerve cells and allows sodium to enter upon painful stimuli. The sodium influx then spurs the nerve cell to send a pain message to the brain.

This channel protein is a promising target for extremely specific and effective pain drugs, Waxman says: "Given that this channel has been indicted, it would be nice if we could develop therapeutic handles that turn it off or down."

Researchers already knew that people with mutations in SCN9A can have extreme pain syndromes. Genetic changes that render the protein completely inactive can leave a person impervious to pain, although otherwise healthy. Other mutations can lead to conditions such as "man on fire" syndrome, in which people experience relentless, searing pain.

Although these syndromes are extreme cases, they strongly implicate SCN9A as important for pain thresholds, Waxman says. The new study is "an important paper that advances our understanding of pain."

In additional laboratory studies, the researchers found that nerve cells carrying the A variant of the gene took longer to close their sodium gates, allowing a stronger pain signal to be sent to the brain. Nerve cells carrying the more common G version of the gene snapped shut faster, stopping the pain signal sooner.

Image: flickr/Lou Mussacchio

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All of Life’s Ingredients Found in Orion Nebula

Posted: 08 Mar 2010 01:16 PM PST

DataPlot_R004

The ingredients for life as we know it have been found in the Orion Nebula.

By finely separating the spectrum of incoming light, astronomers are able to detect the chemical fingerprints of molecules like water and methanol. The spectrograph that their work produces can be seen in the image above. The peaks represent the presence of the molecule indicated.

The new data was collected by the Herschel Telescope, launched into space last year by the European Space Agency. Herschel's HiFi instrument uses a new technique to do more-sensitive spectroscopy. It will enable scientists to better understand the chemistry of space.

The Orion Nebula is located about 1,300 light-years away. No very active star-forming region is closer to Earth. M42, as the nebula is also known, is 24 light-years across.

Image: ESA, HEXOS, HIFI Consortium.

WiSci 2.0: Alexis Madrigal's Twitter, Tumblr, and green tech history research site; Wired Science on Twitter and Facebook.

Kindness Breeds More Kindness, Study Shows

Posted: 08 Mar 2010 12:00 PM PST

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In findings sure to gladden the heart of anyone who's ever wondered whether tiny acts of kindness have larger consequences, researchers have shown that generosity is contagious.

Goodness spurs goodness, they found: A single act can influence dozens more.

In a game where selfishness made more sense than cooperation, acts of giving were "tripled over the course of the experiment by other subjects who are directly or indirectly influenced to contribute more," wrote political scientist James Fowler of the University of California, San Diego, and medical sociologist Nicholas Christakis of Harvard University.

Their findings, published March 8 in the Proceedings of the National Academy of Sciences, are the latest in a series of studies the pair have conducted on the spread of behaviors through social networks.

In other papers, they've described the spread of obesity, loneliness, happiness and smoking. But there was no way to know whether those apparent behavioral contagions were actually just correlations. People who are overweight, for example, might simply tend to befriend other overweight people, or live in an area where high-fat, low-nutrient diets are the norm.

The latest research was designed to identify cause-and-effect links. In it, Fowler and Christakis analyze the results of a so-called public-goods game, in which people were divided into groups of four, given 20 credits each, and asked to secretly decide what to keep for themselves and what to contribute to a common fund. That fund would be multiplied by two-fifths, then divided equally among the group. The best payoff would come if everyone gave all their money — but without knowing what others were doing, it always made sense to keep one's money and skim from the generosity of others.

kindness_networkOnly at the end of each game did players find out what the rest of their group had done. The game was run again and again, each time mixing group members and keeping their identities anonymous, so that decisions were never personal.

When one person gave, others in their group tended to be generous during the next two rounds of play. Recipients of their largess became more generous in turn, and so on down the chain. When a punishment round was added — players could spend their own money to reduce the rewards of selfish players — generosity lasted even longer.

"It is often supposed that individuals in experiments like the one described here selfishly seek to maximize their own payoffs," wrote Fowler and Christakis. "The equilibrium prediction is to contribute nothing and to pay nothing to punish noncontributors, but the subjects did not follow this pattern."

According to the the researchers, the explanation lies not in calculations of odds and rewards, but in simple behavioral mimicry: Monkey see, monkey do, human style. When people are irrationally generous, others follow suit.

The network described by Fowler and Christakis doesn't necessarily replicate natural group dynamics, but suggests a general model for how behaviors spread. They suggest that researchers of altruism and cultural evolution study how different group configurations promote or limit the spread of behaviors.

However, the findings aren't just a feel-good story. Selfish behavior spreads easily, too.

Images: 1) Heath Brandon/Flickr.
2) James Fowler.

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Citation: "Cooperative behavior cascades in human social networks." By James H. Fowler and Nicholas A. Christakis. Proceedings of the National Academy of Sciences, Vol. 107 No. 10, March 9, 2010.

Brandon Keim's Twitter stream and reportorial outtakes; Wired Science on Twitter. Brandon is currently working on a book about ecological tipping points.

Chile Earthquake Moved Entire City 10 Feet to the West

Posted: 08 Mar 2010 10:24 AM PST

chile_eq_zoom1a

The magnitude 8.8 quake that struck near Maule, Chile, Feb. 27 moved the entire city of Concepcion 10 feet to the west.

Precise GPS measurements from before and after the earthquake, the fifth largest ever recorded by seismographs, show that the country's capital, Santiago, moved 11 inches west. Even Buenos Aires, nearly 800 miles from the epicenter, shifted an inch. The image above uses red arrows to represent the relative direction and magnitude of the ground movement in the vicinity of the quake.

The analysis comes from a project led by Ohio State earth scientist Mike Bevis that has been using GPS to record movements of the crust on Chile since 1993. The area is of particular interest to geoscientists because it is an active subduction zone, where an oceanic plate is colliding with a continental plate and being pushed into the Earth's molten mantle below.

The world's largest recorded earthquakes since 1900 have all occurred in subduction zones, including the largest quake ever recorded, which was a magnitude 9.5 in 1960 in Chile not too far from February's earthquake. The second largest was a 9.2 in Alaska in 1964, and the third was the magnitude 9.1 Sumatra quake of 2004 that created the tsunami that killed more than 200,000 people. The fourth largest quake was a magnitude 9 on Russia's Kamchatka peninsula.

Bevis' team hopes to add 50 more GPS stations to its current 25 to better measure the movement and deformation of the crust that will continue for years.

"The Maule earthquake will arguably become one of the, if not the most important great earthquake yet studied," said project scientist Ben Brooks of the University of Hawaii in a press release. "We now have modern, precise instruments to evaluate this event, and because the site abuts a continent, we will be able to obtain dense spatial sampling of the changes it caused."

"As such the event represents an unprecedented opportunity for the earth science community if certain observations are made with quickly and comprehensively," Brooks said.

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Images: University of Hawaii

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