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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.

GENEVA, Aug. 10 (Xinhua) -- In a bid to prevent millions of deaths and suffering every year from malnutrition, the Geneva-based World Health Organization (WHO) launched an online initiative on Wednesday.The e-Library of Evidence for Nutrition Actions (eLENA), according to WHO, offers the latest advice on tackling the three main forms of malnutrition, including undernutrition, vitamin and mineral deficiencies, as well as overweight and obesity.The recommendations by eLENA to tackle malnutrition include promoting breastfeeding and fortifying staple foods with vitamins and minerals such as iron and folic acid for wheat and maize flours.It also recommends using multiple micronutrient powders to fortify foods for children aged between six and 23 months.To prevent anaemia, daily iron and folic supplements are advised for pregnant women, and intermittent iron and folic acid supplementation is recommended for menstruating women and preschool and school-age.While overweight and obesity affect around 1.5 billion adults over age 20, and more than 40 million children aged under five across the world, underweight is the leading risk factor for many diseases in low-income countries and represents about six percent of the world medical burden, WHO statistics showed.

SAN FRANCISCO, June 22 (Xinhua) -- Apple Inc. plans to introduce a new iPhone in September featuring faster chip and more advanced camera, U.S. media reported on Wednesday.The new iPhone model, which will closely resemble iPhone 4, will include the A5 processor, a more powerful chip that Apple added to the iPad 2 tablet computer earlier this year, along with an 8-megapixel camera, up from the 5-megapixel model in the iPhone 4, Bloomberg quoted two people familiar with the product as saying.The device will run the iOS 5 operating system Apple previewed at its annual developer conference earlier this month.Aiming at attracting customers in developing countries, Apple is also working to finish a cheaper version of the iPhone which will use chips and displays of similar quality to the current iPhone 4, said the sources.Meanwhile, it was reported that Apple is also testing a new version of the iPad with a higher resolution screen, which, similar to the one currently used on iPhone 4, will be about one- third higher than iPad 2 and feature a more responsive touchscreen.According to a recent projection on smartphone market by the International Data Corp. (IDC), a small market share decline of iPhone is expected as the smartphone market matures and diversifies in 2011.The release of a new iPhone would help Apple gain more market share as smartphones powered by Google's Android system are predicted to grow to more than 40 percent of the market in the second half of this year.

PARIS, June 19 (Xinhua) -- Commercial Aircraft Corporation of China Ltd. (Comac) on Sunday set up its European office in Paris, the second overseas branch after its U.S. office, marking a new step for China's aviation industry in opening-up and international exchanges."The establishment of Comac Europe office is very significant. It represents the strategic cooperation between China and France and will deepen the two sides' collaboration in aerospace and all areas concerned," Chinese Ambassador Kong Quan said at an opening ceremony, citing Europe's influence in global aerospace industry and civil aviation market."Taking self-dependent innovation as the strategic cornerstone, Comac meanwhile actively conducts international cooperation and draws upon advanced technologies and experience in global civil aviation industry...," Comac President Jin Zhuanglong said.French Secretary of State for Transport Thierry Mariani (4th L), Chinese Ambassador to France Kong Quan (3rd L) and General Manager of the Commercial Aircraft Corporation of China (COMAC) Jin Zhuanglong (2nd R) attend the unveiling ceremony of COMAC Europe Office in Paris, France, June 19, 2011. The COMAC Europe Office was offically opened here Sunday.The Chinese aerospace manufacturer has built up cooperative relationship and partnership with dozens of enterprises and institutions in many countries and regions since its establishment in May 2008 in Shanghai.Regional jet ARJ21 and the trunkliner C919 are two flagship products of the young Chinese company. The group is now working to achieve certification and delivery of ARJ21-700 aircraft by the end of this year, Jin said.With regard to China's C919 trunkliner program, Jin said COMAC has signed cooperation agreements with 17 international companies in the United States and Europe, and has actively explored collaboration with GECAS, British Airways and Ryanair."In the context that the world economy is on recovery from the financial crisis, the civil aviation industry is facing great challenge. We are willing to keep close contact with all relevant public administrations and forge friendly relations and cooperation with overseas suppliers to contribute to the development of world civil aviation industry," Jin said.For the French State Secretary for Transport Thierry Marianne, who also attended the opening ceremony, the Chinese aviation market has great potential in the years to come, and China is estimated to need 3,000 new planes."We have understood that China had decided to build its own aerospace industry. It is a legitimate choice," Marianne said.A demo mock-up of the full-scale forward fuselage of C919 will be displayed during the 49th Paris Air Show on June 20-26, which will be the first time that the 1:1 demo mock-up is to be showcased at an international stage outside China, Jin told Xinhua.During the air show, Comac is going to sign agreements with an international airline and an airborne-system supplier and carry out a series of activities concerning international cooperation and exchanges, according to the group.

WASHINGTON, Sept. 15 (Xinhua) -- A team of researchers has discovered a planet that orbits around a pair of stars, the U.S. space agency NASA announced Thursday.This is the first instance of astronomers finding direct evidence of a so-called circumbinary planet. A few other planets have been suspected of orbiting around both members of a dual-star system, but the transits of the circumbinary planet have never been detected previously.The team, led by Laurance Doyle of the SETI Institute in California, used photometric data from the NASA Kepler space telescope, which monitors the brightness of 155,000 stars.NASA's Kepler mission has discovered a world where two suns set over the horizon instead of just one. The planet, called Kepler-16b, is the most "Tatooine-like" planet yet found in our galaxy. Tatooine is the name of Luke Skywalker's home world in the science fiction movie Star Wars. In this case, the planet it not thought to be habitable. It is a cold world, with a gaseous surface, but like Tatooine, it circles two stars.They found the binary star system by detecting a system where the stars eclipsed each other from the perspective of the Kepler spacecraft. These stars have two eclipses: A primary eclipse when the larger star is partially blocked by the smaller star and a secondary eclipse where the smaller star is fully blocked by the larger star.But the researchers also noticed other times when the brightness of the two stars dropped, even when they were not in an eclipse position. This pattern suggested that there was likely a third object involved. The fact that these so-called tertiary and quaternary eclipses recurred after varying intervals of time, and were of different depths, indicated that the stars were in different positions in their orbit at each instance. This result showed that the tertiary and quaternary eclipses were being caused by something circling both stars, and not an object circling one or the other star.Measurements of the variations in the timing of all four types of eclipses, resulting from the mutual gravitational interactions of the two stars and the third body, demonstrated that the third object was, indeed, a planet. Their work indicates that the planet is less massive than Jupiter, possibly comparable in mass to Saturn, and that the larger of the two binary stars is smaller than our Sun.Their findings will be published Friday in Science."This discovery confirms a new class of planetary systems that could harbor life," Kepler principal investigator William Borucki said in a statement. "Given that most stars in our galaxy are part of a binary system, this means the opportunities for life are much broader than if planets form only around single stars. This milestone discovery confirms a theory that scientists have had for decades but could not prove until now."