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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.

LOS ANGELES, June 9 (Xinhua) -- The edge of our solar system may not be smooth, but filled with a turbulent sea of magnetic bubbles approximately 100 million miles (160 million kilometers) wide, NASA's Jet Propulsion Laboratory (JPL) said on Thursday.The finding was based on observations from NASA's Voyager spacecraft, humanity's farthest deep space sentinels, said JPL in Pasadena, Los Angeles.While using a new computer model to analyze Voyager data, scientists found the sun's distant magnetic field is made up of bubbles which are created when magnetic field lines reorganize, said JPL.The new model suggests the field lines are broken up into self- contained structures disconnected from the solar magnetic field, according to JPL."The sun's magnetic field extends all the way to the edge of the solar system," said astronomer Merav Opher of Boston University. "Because the sun spins, its magnetic field becomes twisted and wrinkled, a bit like a ballerina's skirt. Far, far away from the sun, where the Voyagers are, the folds of the skirt bunch up."Like Earth, our sun has a magnetic field with a north pole and a south pole. The field lines are stretched outward by the solar wind, a stream of charged particles emanating from the star that interacts with material expelled from others in our corner of the Milky Way galaxy.Understanding the structure of the sun's magnetic field will allow scientists to explain how galactic cosmic rays enter our solar system and help define how the star interacts with the rest of the galaxy.The Voyager spacecraft, more than nine billion miles (14 billion kilometers) away from Earth, are traveling in a boundary region. In that area, the solar wind and magnetic field are affected by material expelled from other stars in our corner of the Milky Way galaxy.Launched in 1977, the Voyager twin spacecraft have been on a 33- year journey. They are en route to reach the edge of interstellar space. JPL built the spacecraft and continues to operate them.

WASHINGTON, Aug. 2 (Xinhua) -- The weakness of aging is associated with leaky calcium channels inside muscle cells and a drug already in Phase II clinical trials for the treatment of heart failure might plug those leaks, according to a report published Tuesday in the online edition of Cell Metabolism.Earlier studies by the research team led by Andrew Marks of Columbia University showed the same leaks underlie the weakness and fatigue that come with heart failure and Duchenne muscular dystrophy."It's interesting, normal people essentially acquire a form of muscular dystrophy with age," Marks said. "The basis for muscle weakness is the same." Extreme exercise like that done by marathon runners also springs the same sort of leaks, he added, but in that case damaged muscles return to normal after a few days of rest. A microscopic view shows smooth muscle cells derived from human embryonic stem cells showing the nuclei (blue) and proteins of the cytoskeleton (green) in this handout photo released to Reuters by the California Institute for Regenerative Medicine, March 9, 2009The leaks occur in a calcium release channel called ryanodine receptor 1 (RyR1) that is required for muscles to contract. Under conditions of stress, those channels are chemically modified and lose a stabilizing subunit known as calstabin1.Calcium inside of muscle cells is usually kept contained. When it is allowed to leak out into the cell that calcium itself is toxic, turning on an enzyme that chews up muscle cells. Once the leak starts, it's a vicious cycle. The calcium leak raises levels of damaging reactive oxygen species, which oxidize RyR1 and worsen the leak.The researchers made their discovery by studying the skeletal muscles of young and old mice. They also showed that 6-month-old mice carrying a mutation that made their RyR1 channels leaky showed the same muscular defects and weakness characteristic of older mice.When older mice were treated with a drug known as S107, the calcium leak in their muscles slowed and the animals voluntarily showed about a 50 percent increase in the amount of time spent wheel running. Now in clinical trials for patients with heart failure, the drug is known to work by restoring the connection between costabilin and RyR1.Despite considerable effort to understand and reverse age- related muscle wasting, there are no established treatments available. The new work suggests there may be hope in approaching the problem from a different angle."Most research has focused on making more muscle mass," Marks said. "What's different here is that we are focused not on muscle mass but on muscle function. More muscle doesn't help if it is not functional."

SAN FRANCISCO, June 23 (Xinhua) -- Facebook announced Thursday that Netflix CEO and Chairman Reed Hastings has joined the social network company's board of directors.Hastings, who successfully managed Netflix through an IPO in 2002, is expected to provide useful guidance for Facebook which plans to go public.As the most popular subscription-based movie and television show rental service in the United States, Netflix could also help Facebook figure out how to enter the business of music streaming and movies, which, CEO Mark Zuckerberg said at the eG8 Forum held in Paris last month, would be Facebook's next focus.The Facebook board seat could also help Netflix to catch up with the social evolution of the Internet with its 23.6 million subscribers in the U.S. and Canada."Reed is an entrepreneur and technologist who has led Netflix to transform the way people watch movies and TV," said Zuckerberg in a statement. "He has built a culture of continuous rapid innovation, something we share and work hard to build every day.""Facebook is propelling a fundamental change in how people connect with each other and share all kinds of content," said Hastings. "I'm looking forward to working with Mark and the rest of the board to help Facebook take advantage of all the opportunities ahead."

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