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SAN FRANCISCO, Sept. 12 (Xinhua) -- Amazon.com Inc. is talking with book publishers to launch a rental subscription service for digital books, U.S. media reported on Monday.Several publishing executives said they aren't enthusiastic about the idea because it could lower the value of books and it could also strain their relationships with other retailers that sell their books, The Wall Street Journal quotes people familiar with the matter in a report.The Seattle-based company is considering a digital book library featuring old titles, which would be available to Amazon Prime subscribers, who currently pay 79 U.S. dollars a year for access to digital library of movies and TV shows and unlimited two-day shipping, said the report.Amazon would offer book publishers a substantial fee and could limit the amount of books that Amazon Prime customers could read for free every month, the report cited some sources as saying.The online retailing giant makes the popular electronic reader Kindle and is also reported to launch a color touchscreen tablet before October to compete with Apple's iPad and other devices in the increasingly crowded tablet computer market.The proposal is another sign that retailers are looking for more ways to deliver content digitally as customers increasingly read book and watch TV on personal computers, tablets and other electronic devices, said The Wall Street Journal report.

SYDNEY, Aug. 25 (Xinhua) -- Scientists in Australia have discovered a way of stopping mosquitoes carrying dengue virus, raising hopes for preventing the 50 million human cases of the disease every year, local media reported on Thursday.Groundbreaking experiments in Queensland have found a common insect bacteria, wMel Wolbachia, which can dramatically reduce the presence of dengue fever in mosquitoes.The research, led by Professor Scott O'Neill, Dean at Melbourne's Monash University, was published on Thursday in the prestigious journal, Nature.Australian researchers working on the Eliminate Dengue program aim to protect the mosquitoes themselves from dengue and so stop them transmitting the virus to humans."What the experiments have shown is that this strain of Wolbachia when it is put into mosquitoes really reduces the ability of the (dengue) virus to grow in the mosquito and if it can't grow, then it can't get transmitted in people," O'Neill told reporters.O'Neill said while it was too early to say if the experiments heralded the end of dengue fever, it was a major step towards that goal.In the past decade, there have been 2400 cases of dengue fever reported during 36 outbreaks in Australia.Dengue fever has become endemic in tropical regions, where it is spread by a specific type of mosquito that becomes infected after biting humans with the disease.Despite millions of people being infected with dengue each year, there is currently no way of stopping its rapid spread either by vaccines or controlling mosquito populations.Further trials will be conducted in Cairns in north Queensland over the coming wet season and approval is currently being sought for trials in Thailand, Vietnam, Brazil and Indonesia that will directly determine the effectiveness of the method in reducing dengue disease in human populations, according to Monash University.

HONG KONG, Sept. 9 (Xinhua) -- The Hong Kong Polytechnic University (PolyU) announced Friday that its surveying experts had successfully developed methodologies for precise mapping of the Moon, after intensive analysis of the data captured by the Chinese lunar orbiter ChangE-1 and other lunar exploration missions.According to the PolyU, the team has made significant contributions to lunar mapping. Their efforts culminated in the development of a unique and innovative approach to the creation of accurate 3D models of the lunar surface.The team has produced the most updated parameters of the lunar figure (the shape of the moon), which is essential for lunar mapping using 17.5 million laser altimetry measurements from the ChangE-1and the Japanese SELENE missions.In addition, they also used the new topographic and gravity models to calculate improved crustal thickness and mass distribution of the Moon and established that the average thickness of the Moon's crust is about 40 km on the near side and 50 km on the far side.It was introduced that the resulting lunar mapping was the hard work of a dedicated research team led by Professor Chen Yong-qi, Emeritus Professor of the Department of Land Surveying and Geo-Informatics, who is also serving on the Expert Committee of China's Lunar Exploration Programme (ECCLEP), with the concerted efforts of team members Prof. Chen Wu, Prof. Ding Xiao-li, Prof. Baki Iz, Dr. Bruce King, and Dr. Wu Bo.According to Chen Yong-qi, the lunar mapping project started in 2006. The primary objective was to develop the methodologies and techniques for mapping the Moon surface, which is much more challenging than mapping the Earth's surface because of very few surveyed control points which are essential for accurate map making.Statistics showed that there were only fourteen lunar laser ranging retro reflectors (LRRR) and Apollo lunar surface experiment package (ALSEP) transmitter sites with accurately known coordinates available only on the near side of the Moon, installed by the U.S. Apollo and former Soviet Union Luna missions in the 1960s.Moreover, according to the team, the gravitational field of the Moon is not as well-known as that of Earth, which means the accuracy of the computed lunar satellite's position at any given time is lower than for Earth satellites, thus degrading the mapping accuracy and reliability.In addition, the team expressed that highly reflective lunar surface created significant problems for the automatic processing of images to develop 3D models using the technique of photogramemtry, which is a widely used and highly reliable technique for the creation of maps and 3D models on Earth.Furthermore, the team also revealed they had a plan to compare such data with other data sources in order to evaluate the performance of the ChangE mapping sensors. Since Chen Yong-qi is serving on the ECCLEP, the team has direct access to more recent data captured by the ChangE satellite.

WASHINGTON, July 18 (Xinhua) -- The U.S. National Aeronautics and Space Administration (NASA) on Monday commemorated the 90th birthday of astronaut John Glenn, the first U.S. astronaut to orbit the Earth and also the oldest person to fly to space when he launched on the space shuttle in 1998."John Glenn is a legend, and NASA sends him our best wishes on this major personal milestone," NASA Administrator Charles Bolden said in a statement. "John's legacy and contributions to the continued progress of human spaceflight are immense. His example is one we continue to emulate as we push toward farther destinations in the solar system."After a distinguished flying career with the Marines in World War II and Korea, Glenn joined NASA in 1959 as one of the country' s first astronauts in Project Mercury. On Feb. 20, 1962, Glenn piloted the Mercury-Atlas 6 "Friendship 7" spacecraft on the first U.S. manned orbital mission. He launched from NASA's Kennedy Space Center in Florida to successfully complete three orbits of the Earth.Glenn flew to space again on the STS-95 mission in 1998 aboard the space shuttle Discovery. As a mission specialist, Glenn supported deployment of a variety of research payloads and participated in investigations about spaceflight and the aging process.

XIAMEN, July 23 (Xinhua) -- A rescue and breeding base for endangered Chinese white dolphins started a trial operational period on Saturday in the southeastern seaside resort of Xiamen. The base is the first of its kind in the country.The base, located on the city's Huoshaoyu Islet, includes a rescue center and a breeding area and can accommodate up to four to six white dolphins, said Pan Shijian, vice mayor of Xiamen.Previously, rescuers had to return injured white dolphins back to the sea after giving them simple medical treatment due to the lack of a rescue base, Pan said."From now on, the base will be a hospital for injured or stranded dolphins," he said.The base will also be used as a rehabilitation center for children with infantile autism and brain paralysis, with the dolphins acting as "doctors" during the children's recovery period, he added.The Chinese white dolphin mainly lives in the seas around Xiamen and the Pearl River estuary in south China. The dolphins are under first-class state protection.The Chinese Academy of Fishery Sciences estimates that about 2,000 of the dolphins are living in China's seas.

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