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LOS ANGELES, April 7 (Xinhua) -- Using NASA's Galaxy Evolution Explorer (GEE) satellite, U.S. astronomers are hunting for nearby, hard-to-see stars which could very well be home to the easiest-to-see alien planets, it was announced on Thursday.U.S. astronomers are ferreting out the new targets after the glare of bright, shining stars has frustrated most efforts at visualizing distant worlds, NASA's Jet Propulsion Laboratory (JPL) said.So far, only a handful of distant planets, or exoplanets, have been directly imaged. Small, newborn stars are less blinding, making the planets easier to see, but the fact that these stars are dim means they are hard to find in the first place."Fortunately, the young stars emit more ultraviolet light than their older counterparts, which makes them conspicuous to the ultraviolet-detecting GEE," JPL said in a press release."We've discovered a new technique of using ultraviolet light to search for young, low-mass stars near the Earth," said David Rodriguez, a graduate student of astronomy at University of Californian, Los Angeles. "These young stars make excellent targets for future direct imaging of exoplanets."Young stars, like human children, tend to be a bit unruly -- they spout a greater proportion of energetic X-rays and ultraviolet light than more mature stars. In some cases, X-ray surveys can pick out these youngsters due to the "racket" they cause. However, many smaller, less "noisy" baby stars perfect for exoplanet imaging studies have gone undetected except in the most detailed X-ray surveys. To date, such surveys have covered only a small percentage of the sky, according to JPL in Pasadena, Los Angeles.Rodriguez and his team figured that the GEE, which has scanned about three-quarters of the sky in ultraviolet light, could fill this gap.Astronomers compared readings from the telescope with optical and infrared data to look for the telltale signature of rambunctious junior stars. Follow-up observations of 24 candidates identified in this manner determined that 17 of the stars showed clear signs of youth, validating the team's approach, JPL said."The Galaxy Evolution Explorer can readily select young, low- mass stars that are too faint to turn up in all-sky X-ray surveys, which makes the telescope an incredibly useful tool," Rodriguez said in the release.

WASHINGTON, May 12 (Xinhua) -- Early initiation of antiretroviral treatment in people infected with HIV prevents them from transmitting the virus to their partners, according to findings released Thursday from a large-scale international clinical study.The study, known as HPTN 052, was designed to evaluate whether antiretroviral drugs can prevent sexual transmission of HIV infection among couples in which one partner is HIV-infected and the other is not. The results are the first of their kind from a major randomized clinical trial.Led by Myron Cohen, of the University of North Carolina, the research found that treating HIV-infected individuals with antiretroviral therapy (ART) when their immune systems are still relatively healthy led to a 96 percent reduction in HIV transmission to their partners.This critical new finding convincingly demonstrates that early treatment of infected individuals can have a major impact on the spread of the epidemic.Study investigators enrolled 1,763 couples who were not eligible for ART by WHO standards in nine countries around the world. All couples were at least 18 years of age. The vast majority of the couples (97 percent) were heterosexual, which precludes any definitive conclusions about effectiveness in men who have sex with men.Couples were randomly assigned to one of two study groups. In the first group, the HIV-infected partner initiated antiretroviral therapy (ART) as soon as the couple enrolled in the study (the immediate treatment group); in the second group, infected partners did not begin ART until their CD4+ counts fell to between 200 and 250 cells/mm3 or they developed an AIDS-related illness (the delayed treatment group). Couples in both groups received HIV primary care, counseling and condoms.Results of this research study, which was scheduled to conclude in 2015, are being released early, after the independent data and safety monitoring board (DSMB) determined that the benefits of early treatment were clear.

BEIJING, Jan. 31 (Xinhua) -- A governmental decree which prohibits landlords from dividing apartment rooms into smaller booths for rent will take effect Tuesday.The decree, entitled the Regulations on Leasing of Commercial Housing, stipulates that the average living area of rented housing per person shall not be less than the minimum living area per person set by local governments.Besides, the decree forbids the leasing of kitchens, toilets, basements and balconies to be used as sleeping rooms.The decree is one of several governmental regulations which will take effect on Tuesday.The revised invoice regulations and new regulations on reporting of securities and futures news, price monopoly, and sealing up of property papers by government audit departments will also come into effect.The new regulations on reporting of securities and futures news, jointly issued by the General Administration of Press and Publication and the China Securities Regulatory Commission, stipulate that reporters should be prudent in reporting news that might affect investors' prospects and market stability.

LOS ANGELES, April 12 (Xinhua) -- With the help of NASA Telescopes, astronomers have uncovered one of the youngest galaxies in the distant universe, with stars that formed 13.5 billion years ago, the Jet Propulsion Laboratory (JPL) announced on Tuesday.The finding addresses questions about when the first galaxies arose, and how the early universe evolved, JPL noted in a press release.Infrared data from both the Hubble Space Telescope and the post- coolant, or "warm," phase of NASA's Spitzer Space Telescope mission revealed that the galaxy's stars are quite mature, which means they must have formed when the universe was just a toddler, said JPL in Pasadena, Los Angeles.This challenges theories of how soon galaxies formed in the first years of the universe and could even help solve the mystery of how the hydrogen fog that filled the early universe was cleared, according to astronomers involved in the study.This galaxy is not the most distant ever observed, but it is one of the youngest to be observed with such clarity, JPL said.Normally, galaxies like this one are extremely faint and difficult to study, but, in this case, nature has provided the astronomers with a cosmic magnifying glass, JPL said.The galaxy's image is being magnified by the gravity of a massive cluster of galaxies parked in front of it, making it appear 11 times brighter. This phenomenon is called gravitational lensing."Without this big lens in space, we could not study galaxies this faint with currently available observing facilities," said Eiichi Egami of the University of Arizona in Tucson. "Thanks to nature, we have this great opportunity to see our universe as it was eons ago."The findings may help explain how the early universe became " reionized," according to JPL."Seeing a galaxy as it appeared near the beginning of the universe is an awe-inspiring feat enabled by innovative technology and the fortuitous effect of gravitational lensing," Jon Morse, NASA's Astrophysics Division director at the agency's headquarters in Washington, said in the release."Observations like this open a window across space and time, but more importantly, they inspire future work to one day peer at the stars that lit up the universe following the big bang."

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