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Updated: 13 years 37 weeks ago

Exposing the Student Body: Stanford Joins U.C. Berkeley in Controversial Genetic Testing of Students

Tue, 2010-07-06 15:00

This week, the University of California, Berkeley will mail saliva sample kits to every incoming freshman and transfer student. Students can choose to use the kits to submit their DNA for genetic analysis, as part of an orientation program on the topic of personalized medicine. But U.C. Berkeley isn't the only university offering its students genetic testing. Stanford University's summer session started two weeks ago, including a class on personal genomics that gives medical and graduate students the chance to sequence their genotypes and study the results. [More]

Categories: Science News

Skip the Small Talk: Meaningful Conversations Linked to Happier People

Tue, 2010-07-06 14:00

Feeling down? Having a stimulating conversation might help, according to a new study published in Psychological Science .

Researchers at the University of Arizona and Washington University in St. Louis used unobtrusive recording devices to track the conversations of 79 undergraduate students over the course of four days. They then counted the conversations and determined how many were superficial versus substantive, based on whether the information exchanged was banal (“What do you have there? Pop­corn?”) or meaningful (“She fell in love with your dad? So, did they get divorced soon after?”). They also assessed subjects’ overall well-being by having them fill out question­naires and by asking their friends to report on how happy and content with life they seemed.

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Categories: Science News

Winged Victory: Modern Birds Now Found to Have Been Contemporaries of Dinosaurs (preview)

Tue, 2010-07-06 13:00

December in Moscow, and the temperature drops under 15 degrees below zero. The radiators in the bar have grown cold, so I sit in a thick coat and gloves drinking vodka while I ponder the fossil birds. The year is 2001, and Evgeny N. Kurochkin of the Russian Academy of Sciences and I have just spent hours at the paleontology museum as part of our effort to survey all the avian fossils ever collected in Mongolia by joint Soviet-Mongolian expeditions. Among the remains is a wing unearthed in the Gobi Desert in 1987. Compared with the spectacularly preserved dinosaur skeletons in the museum’s collections, this tiny wing--its delicate bones jumbled and crushed--is decidedly unglamorous. But it offers a strong hint that a widely held view of bird evolution is wrong.

More than 10,000 species of birds populate the earth today. Some are adapted to living far out on the open ocean, others eke out a living in arid deserts, and still others dwell atop snow-capped mountains. Indeed, of all the classes of land vertebrates, the one comprising birds is easily the most diverse. Evolutionary biologists long assumed that the ancestors of today’s birds owed their success to the asteroid impact that wiped out the dinosaurs and many other land vertebrates around 65 million years ago. Their reasoning was simple: although birds had evolved before that catastrophe, anatomically modern varieties appeared in the fossil record only after that event. The dawning of ducks, cuckoos, hummingbirds and other modern forms--which together make up the neornithine (“new birds”) lineage--seemed to be a classic case of an evolutionary radiation in response to the clearing out of ecological niches by an extinction event. In this case, the niches were those occupied by dinosaurs, the flying reptiles known as pterosaurs and archaic birds.

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Categories: Science News

Food for Thought: Creating Edible Illusions--and Great Art [Slide Show]

Tue, 2010-07-06 12:00

Ever been impressed with our modern world's ability to produce meals that look like one food but which are actually made of something else--like a tofu burger or artificial crab meat? It's actually an old trick. In medieval times fish was cooked to imitate venison during Lent, and celebratory banquets included a number of extravagant (and sometimes disturbing) delicacies such as meatballs made to resemble oranges, trout prepared to look like peas, and shellfish fashioned into mock viscera. Recipe books from the Middle Ages and the Renaissance also describe roasted chickens that appeared to sing, peacocks re-dressed in their own feathers and made to breathe fire, and an all-time favorite, a dish aptly named "Trojan Hog," in which a whole roasted pig was stuffed with an assortment of living creatures such as small birds, to the amusement and delight of cherished dinner guests. Unwelcome visitors were also treated to illusory food, but not quite as nice: They were served perfectly good meat that was made to look rotten and writhing with worms. Maybe not appetizing enough to eat, but repulsive enough to send your in-laws packing! [More]

Categories: Science News

Design Boosts Chances for Air-Powered Motorcycle

Tue, 2010-07-06 05:03

Die-hard advocates of alternate energy might fantasize about cars that could one day run on water. But scientists in India have gone a step further. They’ve mathematically modeled an engine that should allow a motorcycle to run on air--compressed air, that is. Their design is described in the Journal of Renewable and Sustainable Energy . [Bharat Raj Singh and Onkar Singh, http://bit.ly/bFd3dO ] [More]

Categories: Science News

Few fishy facts found in climate report

Mon, 2010-07-05 23:03

By Quirin Schiermeier

How much of the Netherlands lies below sea level? It seems an innocuous question-- but it sparked a major review of the work of the Intergovernmental Panel on Climate Change (IPCC).

The investigation, commissioned by the Dutch government, focused on the contribution of Working Group II--on impacts, adaptation and vulnerability--to the IPCC's Fourth Assessment Report. [More]

Categories: Science News

Journals step up plagiarism policing

Mon, 2010-07-05 21:39

By Declan Butler

Major science publishers are gearing up to fight plagiarism. [More]

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Later School Start Time Leads to Better Students

Mon, 2010-07-05 19:57

Teachers get exasperated at students--they don’t pay attention, they’re sleepy, they have bad attitudes. But improvement could be a matter of timing--just start school later. That’s according to a study in the Archives of Pediatrics and Adolescent Medicine . [Citation to come.] [More]

Categories: Science News

How Does Sewage Treatment Work?

Mon, 2010-07-05 15:00

The guy running the snake down our sewer looks matter-of-fact. Our sewage has been backing up. Right next to the pipe connecting our house to the sewer line running down our street stands a 70-year-old willow oak, and I worry the tree's roots have found their way, during the droughty past year, into our line. He shrugs: Maybe it's tree roots, maybe it's a collapsed pipe, maybe it's a yo-yo. The snake went in only a dozen feet or so and found a clog, and now the little claw at the end is spinning. Once he pulls it out we'll know better what's going on. I leave him to his business, though I cast an annoyed glance at the oak. Sewer pipes fit together simply, with a bell joint, and tiny root hairs find their way to the nutrient-rich flow, then grow larger, eventually growing large enough to shatter the vitreous clay pipe that forms so many service lines or dislodge a joint if the pipes are cast iron. Nobody knows what our pipes, 70 years old, are made of, but I fear we're about to find out.

Fifteen minutes later he's winding the snake back up, writing a bill, and exonerating the oak.

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Categories: Science News

Special Report: Europe finds politics and biofuels don't mix

Mon, 2010-07-05 13:27

By Pete Harrison

BRUSSELS (Reuters) - The messages are tense, angry, cajoling.

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Categories: Science News

100 Years Ago: Elegant Flight

Mon, 2010-07-05 13:00

JULY 1960 INFANT MORTALITY -- “The death rate of U.S. infants, after a long and precipitous decline, has leveled off in the last few years, according to a study by Iwao M. Moriyama of the National Office of Vital Statistics. In some states it has even risen slightly, after reaching an all-time low of 26 per 1,000 live births in 1956. Most of the reduction in mortality of children under one year of age is attributable to control of infectious diseases, primarily influenza and pneumonia. In 1946, when penicillin became available to the public, the death from infectious diseases dropped about 30 per cent. However, infectious diseases still account for about half of the deaths among infants between one month and one year old. The death rate for younger infants reflects the heavy toll taken by noninfectious conditions such as congenital malformations, birth injuries, postnatal asphyxia and premature births.”

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Categories: Science News

ICESCAPE scientists scan Arctic seas for melt ponds, "frazil," "grease" and "pancake"

Sun, 2010-07-04 21:45

Editor's Note: Haley Smith Kingsland is an Earth systems master's student at Stanford University specializing in science communication. For five weeks she's in the land of no sunsets participating in ICESCAPE , a NASA-sponsored research cruise to investigate the effects of climate change on the Chukchi and Bering seas. This is her second blog post for Scientific American .

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Categories: Science News

Gulf beaches quiet as spill spreads

Sun, 2010-07-04 18:06

By Sharon Reich

PENSACOLA BEACH, Florida (Reuters) - Gulf coast beaches, normally packed on Independence Day, were quiet on Sunday as workers cleaned up tar balls from BP's leaking oil well while the company was reported to be taking steps to ward off potential takeover bids.

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Categories: Science News

Quitting smoking during pregnancy may not be enough to prevent harm to baby

Sun, 2010-07-04 15:00

Cigarette smoke plays an undisputed role in the development of lung and other cancers. Carcinogens in the smoke damage DNA, which often results in mutations in genes that promote the development of cancer. It's also well known that secondhand smoke can have effects indistinguishable from active smoking. While maternal tobacco smoking has been associated with low birth weight, premature delivery and brain and lung defects, only a few studies have found evidence of genetic mutations in the newborn resulting from exposure to tobacco smoke while in the womb.

A new study by Stephen Grant , professor of environmental and occupational health at the University of Pittsburgh, confirms that both active smoking and passive exposure to secondhand smoke in pregnant women lead to genetic damage in newborns. Importantly, the research shows that there was a similar frequency of mutations among smoking mothers, those exposed to secondhand smoke, and moms-to-be that quit smoking after they learned of their pregnancy. The authors conclude that quitting smoking during pregnancy without actively avoiding exposure to secondhand smoke may not protect the developing fetus. The results were published online June 30 in the Open Pediatric Medicine Journal .

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Categories: Science News

Gulf Coast Dead Zone Set to Grow

Sun, 2010-07-04 14:00
Categories: Science News

Obama commits nearly $2 billion to solar companies

Sun, 2010-07-04 13:59

By Steve Holland

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Categories: Science News

Study shows how sunlight on Titan yields life-precursor compounds

Sat, 2010-07-03 15:00

Titan, Saturn's largest moon, does not harbor alien life as far as anyone knows, but the prospects for extraterrestrial biology there are about as good there as anywhere else in the solar system. [More]

Categories: Science News

Left-sided Cancer: Blame your bed and TV?

Fri, 2010-07-02 21:30

Curiously, the cancer rate is 10 percent higher in the left breast than in the right. This left-side bias holds true for both men and women and it also applies to the skin cancer melanoma. Researchers Örjan Hallberg of Hallberg Independent Research in Sweden and Ollie Johansson of The Karolinska Institute in Sweden, writing in the June issue of the journal Pathophysiology , suggest a surprising explanation that not only points to a common cause for both cancers, it may change your sleeping habits. [More]

Categories: Science News

Winds of Change Blow Renewable Energy Across Latin America [Slide Show]

Fri, 2010-07-02 20:37

On Colombia's La Guajira Peninsula , an arid stretch of land that forms the northernmost tip of South America jutting into the Caribbean Sea, life for the indigenous Wayúu people in many ways remains as it has for centuries. The Wayúu men fish each morning, returning home to their settlements (known as "rancherías") shortly after sunrise, before the sun heats the surrounding desert to 40 degrees Celsius. The Wayúu women weave woolen shoulder bags called "mochilas," which they sell in neighboring towns. Far from the major cities of Colombia's interior, potable water is scarce in La Guajira and electricity is a luxury. [More]

Categories: Science News