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WASHINGTON, July 13 (Xinhua) -- Human neural stem cells are capable of helping people regain learning and memory abilities lost due to radiation treatment for brain tumors, a University of California, Irvine (UCI) study suggests.Research with rats found that stem cells transplanted two days after cranial irradiation restored cognitive function, as measured in one- and four-month assessments. In contrast, irradiated rats not treated with stem cells showed no cognitive improvement."Our findings provide solid evidence that such cells can be used to reverse radiation-induced damage of healthy tissue in the brain," said Charles Limoli, a UCI radiation oncology professor.Study results will appear Friday in Cancer Research, a journal of the American Association for Cancer Research.Radiotherapy for brain tumors is limited by how well the surrounding tissue tolerates it. Patients receiving radiation at effective levels suffer varying degrees of learning and memory loss that can adversely affect their quality of life."In almost every instance, people experience severe cognitive impairment that's progressive and debilitating," Limoli said. " Pediatric cancer patients can experience a drop of up to three IQ points per year."For the UCI study, multipotent human neural stem cells were transplanted into the brains of rats that had undergone radiation treatment. They migrated throughout the hippocampus -- a region known for the growth of new neurons -- and developed into brain cells.Researchers assessed the rats one month and four months after transplantation, noting enhanced learning and memory abilities at both intervals.Additionally, they found that transplanting as few as 100,000 human neural stem cells was sufficient to improve cognition after cranial irradiation. Of cells surviving the process, about 15 percent turned into new neurons, while another 45 percent became astrocytes and oligodendrocytes -- cells that support cerebral neurons.Most notably, Limoli said, he and his colleagues discovered that about 11 percent of the engrafted cells expressed a behaviorally induced marker of learning, indicating the functional integration of those cells into memory circuits in the hippocampus."This research suggests that stem cell therapies may one day be implemented in the clinic to provide relief to patients suffering from cognitive impairments incurred as a result of their cancer treatments," Limoli said.

LOS ANGELES, July 18 (Xinhua) -- The spacecraft Dawn of the National Aeronautics and Space Administration (NASA) has returned the first close-up image of the giant asteroid Vesta after entering its orbit for the first time last week, the Jet Propulsion Laboratory (JPL) announced on Monday.The image taken for navigation purposes shows Vesta in greater detail than ever before, said JPL in Pasadena, California.On July 15, Dawn became the first probe to enter orbit around an object in the main asteroid belt between Mars and Jupiter.When Vesta captured Dawn into its orbit, there were approximately 9,900 miles (about 16,000 kilometers) between the spacecraft and the asteroid.Vesta is 330 miles (about 530 kilometers) in diameter and the second most massive object in the asteroid belt.NASA's Dawn spacecraft obtained this image with its framing camera on July 17, 2011. It was taken from a distance of about 9,500 miles (15,000 kilometers) away from the protoplanet Vesta. Each pixel in the image corresponds to roughly 0.88 miles (1.4 kilometers). Ground- and space-based telescopes have obtained images of Vesta for about two centuries, but they have not been able to see much detail on its surface."We are beginning the study of arguably the oldest extant primordial surface in the solar system," said Dawn principal investigator Christopher Russell from the University of California, Los Angeles, which is responsible for Dawn's mission science. " This region of space has been ignored for far too long. So far, the images received to date reveal a complex surface that seems to have preserved some of the earliest events in Vesta's history, as well as logging the onslaught that Vesta has suffered in the intervening eons."Vesta is thought to be the source of a large number of meteorites that fall to Earth. Vesta and its new NASA neighbor, Dawn, are currently approximately 117 million miles (about 188 million kilometers) away from Earth. The Dawn team will begin gathering science data in August.Observations will provide unprecedented data to help scientists understand the earliest chapter of the solar system and pave the way for future human space missions, according to JPL."Dawn slipped gently into orbit with the same grace it has displayed during its years of ion thrusting through interplanetary space," said Marc Rayman, Dawn chief engineer and mission manager at NASA's JPL. "It is fantastically exciting that we will begin providing humankind its first detailed views of one of the last unexplored worlds in the inner solar system."Although orbit capture is complete, the approach phase will continue for about three weeks. During approach, the Dawn team will continue a search for possible moons around the asteroid; obtain more images for navigation; observe Vesta's physical properties; and obtain calibration data.In addition, navigators will measure the strength of Vesta's gravitational tug on the spacecraft to compute the asteroid's mass with much greater accuracy than has been previously available, according to JPL.Dawn will spend one year orbiting Vesta, then travel to a second destination, the dwarf planet Ceres, arriving in February 2015. The mission to Vesta and Ceres is managed by JPL for the agency's Science Mission Directorate in Washington.Dawn is a project of the directorate's Discovery Program, which is managed by NASA's Marshall Space Flight Center in Huntsville, Alaska.

SINGAPORE, June 14 (Xinhua) -- Researchers from Singapore and China are conducting a research aimed at using different technologies to completely capture and convert carbon dioxide in industrial emissions into energy, local daily Lianhe Zaobao reported on Tuesday.The project, supported by the National Research Foundation (NSF) of Singapore, will make use of sunlight as well as photochemical and photosynthetic processes, the foundation said.The researchers involved in the five-year project are from China's Peking University and Singapore's National University of Singapore and the Nanyang Technological University. A research center will be established under the Campus for Research Excellence and Tehnological Enterprise, a program also known as CREATE, the foundation said.It will be the first project involving cooperation with a Chinese university under the program. It will be located at the University Town of the National University of Singapore due to be completed by the end of the year.Lee Yuan-Kun, a researcher at the National University of Singapore, said no single chemical process can capture and convert the carbon dioxide completely so the researchers will be first treating the emissions with photochemical and electrochemical processes to convert most of the carbon dioxide into energy resources such as methane.The gas with thinner carbon dioxide will then be used to grow microalgae, he said.Nevertheless, for the cost of renewable energy to be close to that of fossil fuel, the efficiency will have to be drastically improved by about five to 10 times, Lee said.The project is one of three energy research projects to be housed under the Campus for Research Excellence and Tehnological Enterprise program.Zhang Dongxiao, from the College of Engineering at Peking University, said that the research program seeks to develop energy efficient and environmentally friendly carbon capture technologies that can be applied in the manufacturing and chemical industries, and that it complements Peking University's strong capability in carbon storage."Reducing carbon intensity will not only benefit both countries in terms of cost competitiveness of products made, but also portrays a good image on our national responsibility to achieve a sustainable Earth," Zhang said. 

WELLINGTON, Sept. 27 (Xinhua) -- New Zealand and Japanese scientists are teaming up to develop healthier foods under two government-funded "functional foods" projects.One project, to be led by New Zealand's Massey University, will work with New Zealand food companies to create and develop a functional food with specific health enhancing effects for menopausal women, New Zealand Science and Innovation Minister Wayne Mapp announced Tuesday.The other project, to be led in New Zealand by Plant and Food Research, would use mass spectrometry to develop a "metabolic atlas" of the chemical composition of allium vegetables, such as onions and garlic, which the horticultural industry could use to develop new food products with health benefits.Mapp said the two research projects would be awarded a total of 1 million NZ dollars (782,000 U.S. dollars) in funding to strengthen collaborative research relationships between New Zealand and Japan, Mapp said."These research projects have strong commercial potential, including through the Japanese market, and so have the potential to benefit our economy," said Mapp."The government is committed to building and strengthening research relationships with other countries that will achieve world-class scientific results and lead to new innovative technologies."The two projects awarded funding under Ministry of Science and Innovation's Japan Science and Technology Agency (JST) funding round focus on functional foods. The ministry and Japan each fund half the cost of each research project awarded funding.

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.

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