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News Bytes of the Week—In Judo, Blue Is Not Best

Leaky muscles, Bulletproof iPod charger and more…
Two Judo Fighters



Cpl. Jeff Sisto / United States Marine Corps.

Blue duds win judo matches? Maybe not
Researchers scored a takedown this week on a 2005 study that found an inexplicable advantage for judo players in blue outfits squaring off against contenders wearing white in the 2004 Olympics. The finding implied that maybe the blue was more intimidating or made blows harder to see coming. Skeptical, evolutionary biologists from Scotland and the Netherlands took a closer look at the Olympic matchups and noticed that because of the way the tournament was structured, higher-seeded grapplers wore blue more often than white (they alternated outfits, or judogi, between matches), and blue-clad contestants were more likely to have had extra rest between matches as well as more matches to that point than their white-garbed opponents. When the researchers controlled for these effects in the Olympic matches, the advantage of donning a blue judogi disappeared. (Proceedings of the Royal Society B)

Fake antimalaria drugs seized
Members of an international task force this week released details of an investigation that led to the arrest of a man from China's Yunnan Province in 2006 for allegedly trafficking almost a quarter of a million doses' of a fake antimalaria drug. One of the few effective strategies against malaria—a mosquito-borne disease that claims the lives of more than a million people a year in Africa and Asia—is artemisinin, or qinghaosu, a compound derived from the Chinese herb artemisia (wormwood). But there has been a growing black market for pills passed off as artemisinin-based, leaving duped buyers vulnerable to the potentially deadly condition.

In an effort to crack down on bogus suppliers, the International Criminal Police Organization (INTERPOL) and the World Health Organization Regional Office for the Western Pacific organized a group of scientists, public health workers and law enforcement officers in 2006 to trace the source of the fakes. Researchers confirmed that 195 (49.9 percent) of 391 suspected counterfeit samples of artesunate (an artemisinin derivative) collected in Southeast Asia were indeed bogus, containing at most 12 milligrams of the ingredient per tablet, compared with about 50 milligrams per genuine tablet. Chinese authorities traced some of the samples back to southern China, where they seized 24,000 packs (10 percent) linked to the Yunnan suspect. They say the rest may account for up to half the artesunate sold to neighboring Myanmar. (PLoS Medicine)

A bulletproof shirt that charges your iPod, too
Think your shirt's cool? Well, nanotech researchers at the Georgia Institute of Technology are developing one made of DuPont Kevlar fibers covered with zinc oxide nanowires designed to harness energy from your body's motion (a type of piezoelectric effect) and convert it into enough juice to charge your iPod or cell phone. The hybrid microfiber–nanowire material is based on prototype nanogenerators made of parallel zinc oxide nanowires, which stimulate an electric current when they are bent by ultrasonic waves, blood flow or other environmental mechanical vibrations. The new microfiber system is made from softer materials designed to capture energy from low-frequency mechanical energy—aka the swinging of your limbs. Just be careful not to toss the shirt in the wash or get too sweaty: zinc oxide is sensitive to moisture, and the nanowires won't work well if they are soaked and shorting out. (Nature)

Green submarine feeds off the ocean's warmth
In another example that there is a free lunch—or at least a borrowed one—the latest in autonomous robotic submersible gets its power from the ocean around it. Built by the Webb Research Corporation in East Falmouth, Mass., the environmentally friendly sub has already made 20 round-trips between two of the U.S. Virgin Islands, St. Thomas and St. Croix. A group from the Woods Hole Oceanographic Institution announced this week it would use data gathered by the robot vessel to study ocean currents. When the sub moves from cooler water to warmer areas, its internal wax tubes heat up and expand, squeezing gas contained in surrounding tanks to store energy that can later be used to power the vehicle. Researchers say the sub could operate like this for up to two years, whereas its battery-dependent predecessors were good for no longer than six months. (Woods Hole)

Airplanes raise blood pressure while you sleep
Now here's something that will make your blood pressure soar—literally. A new study shows that nighttime noise from aircraft and traffic can increase your blood pressure even if it doesn't wake you.  Scientists at the Imperial College London (I.C.L.) and other European institutions monitored the blood pressure (at 15-minute intervals) of 140 sleeping volunteers in their homes near London Heathrow and three other major European airports. Their findings, published this week in European Heart Journal: subjects' blood pressure rose noticeably after they experienced a so-called noise event—defined as a sound louder than 35 decibels—such as jets roaring overhead, traffic passing outside or even a bedmate's loud snoring. In many cases, participants' were clueless because many continued to snooze through the racket. Researchers found that the size of spikes correlated with volume; that is, the louder the sound, the bigger the jump in pressure. Aircraft noise events caused an average increase in systolic blood pressure of 6.2 millimeters of mercury (mmHg) and an average hike in diastolic blood pressure of 7.4 mmHg; other clatter produced similar effects.

The research comes on the heels of findings by the same researchers showing that people who have lived under an airport flight path for at least five years have a greater risk of developing high blood pressure than populations living in quieter zones. "We know that noise from air traffic can be a source of irritation, but our research shows that it can also be damaging for people's health, which is particularly significant in light of plans to expand international airports," said co-author Lars Jarup of I.C.L.'s Division of Epidemiology, Public Health and Primary Care. "Our studies show that nighttime aircraft noise can affect your blood pressure instantly and increase the risk of hypertension. It is clear to me that measures need to be taken to reduce noise levels from aircraft, in particular during nighttime, in order to protect the health of people living near airports." Sleep tight. (I.C.L.)


What do marathoners and heart-failure patients have in common?

Apparently, leaky muscles. Researchers report in the online edition of the Proceedings of the National Academy of Sciences USA that the fatigue extreme athletes feel after a race and that heart-failure patients routinely experience is probably caused by the same condition: a tiny leak that allows calcium to continuously drip inside their muscle cells. According to senior study author Andrew Marks and colleagues at Columbia University Medical Center, the leak weakens the force produced by the muscle and also releases a protein-digesting enzyme that damages the muscle fibers, reducing the ability of a single muscle to contract repeatedly before losing strength. Scientists discovered the leaky muscles in mice put through a grueling three-week swimming regimen and in humans after three days of intense cycling. The findings mimicked earlier ones they found in animals with heart trouble. But don't think this gives you an excuse to be a lazy bum.

"The study does not mean exercise is bad for you," Marks stressed. "We only saw the leak in animals and human athletes that exercised three hours a day at very high intensities for several days or weeks in a row until they were exhausted." What's more, he noted, the athletes' muscles returned to normal after a few days of R&R. People with chronic heart failure, on the other hand, had the problem even though they didn't do a lick of exercise; and unfortunately, their damaged arm, leg and breathing muscles didn't bounce back. But researchers also found that an experimental drug they had developed relieved muscle fatigue in mice after exercise, suggesting that it may also perk up patients with chronic heart failure who are sometimes too weary to even get out of bed. (Columbia University Medical Center)

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