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WASHINGTON, Aug. 31 (Xinhua) -- Astronomers using NASA's Chandra X-ray Observatory discovered the first pair of supermassive black holes in a spiral galaxy similar to the Milky Way, NASA announced Wednesday.Approximately 160 million light years from Earth, the pair is the nearest known such phenomenon.The black holes are located near the center of the spiral galaxy NGC 3393. Separated by only 490 light years, the black holes are likely the remnant of a merger of two galaxies of unequal mass a billion or more years ago.Both of the supermassive black holes are heavily obscured by dust and gas, which makes them difficult to observe in optical light. Because X-rays are more energetic, they can penetrate this obscuring material. Chandra's X-ray spectra show clear signatures of a pair of supermassive black holes."If this galaxy weren't so close, we'd have no chance of separating the two black holes the way we have," said Pepi Fabbiano of the Harvard-Smithsonian Center for Astrophysics, who led the study that appeared Wednesday in on-line issue of the journal Nature. "Since this galaxy was right under our noses by cosmic standards, it makes us wonder how many of these black hole pairs we've been missing."Previous observations in X-rays and at other wavelengths indicated that a single supermassive black hole existed in the center of NGC 3393. However, a long look by Chandra allowed the researchers to detect and separate the dual black holes. Both black holes are actively growing and emitting X-rays as gas falls towards them and becomes hotter.When two equal-sized spiral galaxies merge, astronomers think it should result in the formation of a black hole pair and a galaxy with a disrupted appearance and intense star formation. A well-known example is the pair of supermassive black holes in NGC 6240, which is located about 330 million light years from Earth.However, NGC 3393 is a well-organized spiral galaxy, and its central bulge is dominated by old stars. These are unusual properties for a galaxy containing a pair of black holes.

CANBERRA, Sept. 7 (Xinhua) -- A team of Australian and U.S. scientists on Wednesday said they discovered a genetic defect, which can lead to Leigh syndrome, a rare disorder which affects the central nervous syndrome.The scientists tested more than 1000 genes by encoding proteins active in two individuals who suffer from the illness. They used a new technique known as next-generation DNA sequencing to examine the genes.The gene they discovered encodes an enzyme which is found in the mitochondria which are subsets of cells. Without this enzyme the mitochondria do not translate proteins efficiently, and this then causes Leigh syndrome.According to David Thorburn, from the Murdoch Children's Research Institute in Melbourne, the discovery shows the enormous potential of the new technology."These findings demonstrate the ability of sequencing technologies to improve diagnosis," Professor Thorburn said in a statement released on Wednesday."Although it isn't clear in the case of Leigh syndrome whether the precise molecular diagnosis will necessarily lead to therapies, the current findings represent a meaningful service."He added that diagnosis of the disease along with its specific genetic cause can also be informative about the risk a couple has of having another affected child. The diagnostic information can help in decisions about whether and how to pursue alternative means of having children, for instance through the use of donor sperm or eggs.The research team consisted of scientists from Australia's Murdoch Institute as well as the Broad Institute in the U.S.In Leigh syndrome, infants are born apparently healthy only to develop movement and breathing disorders that worsen over time, often leading to death by the age of three. The problem is that the mitochondria responsible for powering their cells cannot keep up with the demand for energy in their developing brains.

WASHINGTON, June 15 (Xinhua) -- Using the deepest X-ray image ever taken, astronomers found the first direct evidence that massive black holes were common in the early universe, the U.S. National Aeronautics and Space Administration (NASA) said Wednesday in a statement.The discovery from NASA's Chandra X-ray Observatory shows that very young black holes grew more aggressively than previously thought, in tandem with the growth of their host galaxies.By pointing Chandra at a patch of sky for more than six weeks, astronomers obtained what is known as the Chandra Deep Field South (CDFS). When combined with very deep optical and infrared images from NASA's Hubble Space Telescope, the new Chandra data allowed astronomers to search for black holes in 200 distant galaxies, from when the universe was between about 800 million to 950 million years old."Until now, we had no idea what the black holes in these early galaxies were doing, or if they even existed," said Ezequiel Treister of the University of Hawaii, lead author of the study to appear Thursday in journal Nature. "Now we know they are there, and they are growing like gangbusters."The super-sized growth means that the black holes in the CDFS are less extreme versions of quasars -- very luminous, rare objects powered by material falling onto supermassive black holes. However, the sources in the CDFS are about a hundred times fainter and the black holes are about a thousand times less massive than the ones in quasars.The observations found that between 30 and 100 percent of the distant galaxies contain growing supermassive black holes. Extrapolating these results from the small observed field to the full sky, there are at least 30 million supermassive black holes in the early universe. This is a factor of 10,000 larger than the estimated number of quasars in the early universe."It appears we've found a whole new population of baby black holes," said co-author Kevin Schawinski of Yale University. "We think these babies will grow by a factor of about a hundred or a thousand, eventually becoming like the giant black holes we see today almost 13 billion years later."

GENEVA, Aug. 19 (Xinhua) -- The World Health Organization (WHO) and the UN Children's Fund (UNICEF) started an emergency vaccination campaign in all accessible areas of South and Central Somalia, WTO spokesperson Tarek Jasarevic said here on Friday.In July 2011 alone, 1,019 suspected measles cases and 31 related deaths were reported in South and Central Somalia, representing 20 percent of all reported cases for this year.The major factors for a measles outbreak in Somalia are low coverage, malnutrition, population movements, and overcrowed internally displaced (IDP) camps."WHO fears that the measles outbreak could affect a high number of people, especially among the vulnerable IDPs whose overall health is already fragile," Jasarevic said.About 2.5 million children aged between 6 and 15 in 10 regions of South and Central Somalia, including children in Mogadishu, will be targeted during this campaign.

BEIJING, Sep. 13 (Xinhuanet) --Experts have called for a national drug-control system after a nationwide deficit of a life-saving drug, which has lasted at least three months.Doctors at a Beijing hospital said some specialized hospitals, which perform hundreds of cardiac operations every month, have been paralyzed by their lack of protamine sulfate, which is commonly administered after heart surgery to reverse the anticoagulant effects of heparin.The earliest report of a shortage was in Hubei province on July 21. This was followed by reports of shortages in Guangdong, Shandong and Liaoning provinces.The Shandong newspaper, Qilu Evening News, quoted a regional sales manager, surnamed Zhuang, as saying the province had been allocated 150 doses of protamine sulfate after Shanghai No 1 Biochemical and Pharmaceutical Co Ltd recently resumed production of the drug."But its monthly use here is usually 10,000 doses," he said.The Ministry of Health has denied it is responsible for supplies of the drug and passed the buck to the State Food and Drug Administration, claiming the latter is responsible for the supervision of medicines.Shen Chen, head of the publicity office of the State Food and Drug Administration, said he was unaware of the shortage, but said the administration is responsible for the quality of medicines, not the supply."Development and reform authorities oversee the medicines' prices, while the industrial and commercial authorities oversee the storage. The food and drug departments only cover the approval and quality of medicines."Industry insiders said one of the reasons for the shortage was the low profit margin, which discourages companies from mass producing the drug."Some companies can't earn enough to recover their costs, therefore it is almost impossible to maintain their enthusiasm for continuing production," said Lu Guoping, secretary-general of the Shanghai Pharmaceutical Trade Association.Lu said the government should issue policies to prevent future shortages of such medicines to avoid possible nationwide public health incidents.Yi Shenghua, a lawyer at Beijing Yingke Law Firm, said the country should have a unified system to guarantee the normal supply of medicines that are widely used and drug manufacturers should fulfill their responsibilities to society, even though there is no law stipulating they should produce specific medicines.He came up with two ways to deal with the problem of companies only producing profitable drugs."The government can order businesses to manufacture a certain amount of cheap medicines. Or it can offer financial assistance to subsidize cheap, but life-saving medicines."

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