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SAN FRANCISCO, June 14 (Xinhua) -- Google on Tuesday unveiled voice search for desktop computers and search-by-image, two new features allowing users to speak their search into the computer and search with the help of images.Speaking at the Internet search giant's Inside Search Event in San Francisco, Mike Cohen, head of Google's speech technology efforts, said its voice search is now available in 27 languages and dialects, an estimated coverage of around 5 billion people or two-thirds of world population.Voice search has already been available in Google's mobile search application from 2008. Adding the feature to desktops is part of Google's strategy to bring mobile innovations to its desktop search.The voice search on desktop performs similarly to voice search on smartphones -- users can click the microphone button and speak the query. It is only available via Google's Chrome browser for now.Cohen noted that the volume of Google mobile speech inputs has increased by six times in the last year.Also at the event, Google introduced search-by-image, which enables users to drag-and-drop, copy-and-paste image URL, or upload the image from the desktop into the search box. They can also use a Chrome or FireFox software extension to add images to the search.Google said the search-by-image feature will be available in most countries and regions over the next few days to Chrome users, noting that it will not collect and store any images that users use.

LOS ANGELES, June 20 (Xinhua) -- About 8 percent of children, or nearly 6 million in the U.S., have a food allergy, a much higher rate than previously estimated, a new study suggests.Not only is this estimate higher than some previous research has reported, allergic reactions are often severe and that many kids have more than one allergy, according to the study published online in Pediatrics on Monday.Of the children with confirmed (or probable) food allergies, about 39 percent had had severe reactions in the past, and 30 percent had more than one allergy, the study found.In the current study, researchers at the Northwestern University Feinberg School of Medicine surveyed parents of more than 38,000 children about whether their child had been diagnosed with a food allergy and had one or more of a number of symptoms, including anaphylaxis; swelling of the lips, eyes or face and skin rashes or hives.The study pinned down peanuts (25 percent of food-allergic children), milk (21 percent) and shellfish (17 percent) as the top three allergens.Severe reactions were most common among children with tree nut (more than 50 percent) and fin fish (more than 40 percent) allergies. The reactions were more likely among 14- to 17-year- olds compared with 0- to 2-year-olds, and more likely in children with multiple food allergies, the study found."These findings provide critical epidemiologic information to guide strategies for the prevention of food-induced reactions and for the diagnosis and management of childhood food allergies," the study noted.

LOS ANGELES, June 17 (Xinhua) -- The size of low-oxygen zones created by respiring bacteria is extremely sensitive to changes in depth caused by oscillations in climate, thus posing a distant threat to marine life, a new study suggests."The growth of low-oxygen regions is cause for concern because of the detrimental effects on marine populations -- entire ecosystems can die off when marine life cannot escape the low- oxygen water," said lead researcher Curtis Deutsch, assistant professor of atmospheric and oceanic sciences at University of California, Los Angeles."There are widespread areas of the ocean where marine life has had to flee or develop very peculiar adaptations to survive in low- oxygen conditions," Deutsch said in the study to be published in an upcoming print edition of the journal Science.A team led byDeutsch used a specialized computer simulation to demonstrate for the first time that fluctuations in climate can drastically affect the habitability of marine ecosystems.The study also showed that in addition to consuming oxygen, marine bacteria are causing the depletion of nitrogen, an essential nutrient necessary for the survival of most types of algae."We found there is a mechanism that connects climate and its effect on oxygen to the removal of nitrogen from the ocean," Deutsch said. "Our climate acts to change the total amount of nutrients in the ocean over the timescale of decades."Low-oxygen zones are created by bacteria living in the deeper layers of the ocean that consume oxygen by feeding on dead algae that settle from the surface. Just as mountain climbers might feel adverse effects at high altitudes from a lack of air, marine animals that require oxygen to breathe find it difficult or impossible to live in these oxygen-depleted environments, Deutsch said.Sea surface temperatures vary over the course of decades through a climate pattern called the Pacific Decadal Oscillation, during which small changes in depth occur for existing low-oxygen regions, Deutsch said. Low-oxygen regions that rise to warmer, shallower waters expand as bacteria become more active; regions that sink to colder, deeper waters shrink as the bacteria become more sluggish, as if placed in a refrigerator."We have shown for the first time that these low-oxygen regions are intrinsically very sensitive to small changes in climate," Deutsch said in remarks published Friday by the American Association for the Advancement of Science on its website. "That is what makes the growth and shrinkage of these low-oxygen regions so dramatic."Molecular oxygen from the atmosphere dissolves in sea water at the surface and is transported to deeper levels by ocean circulation currents, where it is consumed by bacteria, Deutsch said."The oxygen consumed by bacteria within the deeper layers of the ocean is replaced by water circulating through the ocean," he said. "The water is constantly stirring itself up, allowing the deeper parts to occasionally take a breath from the atmosphere."A lack of oxygen is not the only thing fish and other marine life must contend with, according to Deutsch. When oxygen is very low, the bacteria will begin to consume nitrogen, one of the most important nutrients that sustain marine life."Almost all algae, the very base of the food chain, use nitrogen to stay alive," Deutsch said. "As these low-oxygen regions expand and contract, the amount of nutrients available to keep the algae alive at the surface of the ocean goes up and down. "Understanding the causes of oxygen and nitrogen depletion in the ocean is important for determining the effect on fisheries and fish populations, he said.

WASHINGTON, July 7 (Xinhua) -- Space shuttle Atlantis will soar into the sky Friday on NASA's 135th and final flight. Its scheduled return to Earth later this month will mark the end of NASA's 30-year space program.Since its onset with the launch of space shuttle Columbia, the program has been seen as a cheap, safe and reliable way for space exploration.Despite its great contributions to U.S. manned space flight, it has also left some grave and tragic lessons, making its termination inevitable.HIKING COSTSLaunched in 1972 by then President Richard Nixon, the shuttle program aimed to provide a new system of affordable space travel and proved to be NASA's most enduring project in its 50 years of existence.In 1981, shuttle Columbia made its first shuttle flight for two days. It was the ultimate hybrid and the first reusable spacecraft.Launched like a rocket and gliding back to Earth like an airplane, space shuttles not only can act as a space taxi to carry astronauts, but have the muscle of a long-distance trucker to haul heavy machinery.The spaceship boasts more than 3,500 subsystems and 2.5 million parts and is nine times faster than a speeding bullet as it climbs heavenward. That versatility, however, has translated into higher costs.NASA originally estimated the program would cost about 90 billion U.S. dollars. However, its actual cost stands at about 200 billion dollars, compared with the 151 billion dollars spent on Apollo which took Americans to the moon in 1969.In an article in Technology Review, John Logsdon, former head of the Space Policy Institute at George Washington University, drew a direct connection between the ravenous shuttle budget and the lack of other large advances in manned space flight."By operating the system for 30 years, with its high costs and high risk, rather than replacing it with a less expensive, less risky second-generation system, NASA compounded the original mistake of developing the most ambitious version of the vehicle," he wrote."The shuttle's cost has been an obstacle to NASA starting other major projects," he added.HIGH RISKIn terms of safety, the shuttles have never been as reliable as their designers had envisioned.On average, one out of every 67 flights ended up with fatal accidents. Based on the rate of deaths per million miles traveled, the space shuttle is 138 times riskier than a passenger jet.Seven astronauts onboard died when Challenger exploded about a minute after launch in 1986. Nearly two decades after the tragic blast, a new catastrophe descended when the shuttle Columbia disintegrated moments before landing in 2003, killing another seven spacemen.Again, the shuttle program was shelved for more than two years as NASA stepped up efforts to make it safer. But experts say the fundamental problem related to shuttles' safety cannot be solved due to their "birth defects.""It is in the nation's interest to replace the Shuttle as soon as possible," concluded the panel that investigated the 2003 Columbia accident.

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