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CANBERRA, Aug. 17 (Xinhua) -- Australian scientist on Wednesday said his international research team has discovered the trick on how butterfly learn to change its wing pattern to avoid being eaten by birds.The Amazonian butterfly, Heliconius numata, has learnt to carry out a single genetic switch to alter its wing pattern so it appears to be another bad-tasting butterfly that birds will avoid.Dr. Siu Fai (Ronald) Lee from the Department of Genetics and Bio21 Institute at Australia's University of Melbourne was part of the international research team, which was led by scientists at Centre National de la Recherche Scientifique (CNRS) and the University of Exeter in United Kingdom.Dr. Lee said the historical mystery had puzzled researchers for decades."Charles Darwin was puzzled by how butterflies evolved such similar patterns of warning coloration," Dr. Siu Fai (Ronald) Lee from the Department of Genetics and Bio21 Institute at the University of Melbourne told Western Australia Today."We have now solved this mystery, identifying the region of chromosome responsible for changing wing pattern."He said the research team identified a genetic switch known as a supergene, which allowed the butterfly to morph into several different forms, allowing one species to mimic another."It is amazing that by changing just one small region of the chromosomes, the butterfly is able to fool its predators by mimicking a range of different butterflies that taste bad," he said."The butterflies rearrange this supergene DNA like a small pack of cards, and the result is new wing patterns. It means that butterflies look completely different but have the same DNA."There are other butterflies doing similar tricks, but this is the most elegant one."I was just fascinated by how elegant they were."He said the discovery proves that small chromosomal changes can preserve successful gene combinations, and thus help a species to adapt.The findings of the study are published on August 14 in the international journal Nature.

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, Aug. 10 (Xinhua) -- After a journey of almost three years, NASA's Mars rover Opportunity has reached the Red Planet's Endeavour crater to study rocks never seen before, the U.S. National Aeronautics and Space Administration (NASA) announced on Wednesday.Scientists hope it will find rocks and terrain much older than any other that the itinerant robot has examined during its seven years on the red planet.The U.S. space agency said that Opportunity arrived at the rim of Endeavour on Tuesday. The golf cart-size rover is expected to remain at the 22-kilometer-wide crater for the next few years.A portion of the west rim of Endeavour crater sweeps southward in this color view from NASA's Mars Exploration Rover Opportunity."NASA is continuing to write remarkable chapters in our nation' s story of exploration with discoveries on Mars and trips to an array of challenging new destinations," NASA Administrator Charles Bolden said in a statement. "Opportunity's findings and data ... will play a key role in making possible future human missions to Mars and other places where humans have not yet been."NASA's Mars Reconnaissance Orbiter, which has been circling the planet since late 2005, detected clay minerals that form in wet conditions in the crater. Scientists want to find out if the minerals date back to Mars' distant past, when the planet is believed to have been wetter and warmer than the dry frozen desert it is today."We're soon going to get the opportunity to sample a rock type the rovers haven't seen yet," said Matthew Golombek, Mars Exploration Rover science team member, at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "Clay minerals form in wet conditions so we may learn about a potentially habitable environment that appears to have been very different from those responsible for the rocks comprising the plains."NASA is searching for signs that Mars had a habitable environment billions of years ago. Knowledge of the Martian climate will be important to future manned missions there, and can shed light on the forces that shaped Earth's climate.NASA launched the Mars rovers Opportunity and Spirit in 2003 for what were planned to be three-month missions. But both continued operating well beyond that. Spirit stopped communicating in March 2010.

UNITED NATIONS, Sept. 19 (Xinhua) -- Mohammad Hossein Niknam, acting minister of health in international affairs of Iran, said here on Monday that his country is working to prevent and counteract the non-communicable diseases (NCDs), which have had significant effect on the population."NCDs have traditionally been more prevalent in affluent societies," he said. "However, they are increasingly becoming common in many developing countries, and in particular among the less affluent groups. The Eastern Mediterranean Region (EMRO) as others is suffering a heavy burden of NCD diseases and Iran is no exception: the total burden of disease for NCDs is 45 percent for males and 33 percent for females."Niknam's statements came as he addressed the UN General Assembly High-Level Meeting on Prevention and Control of Non- communicable Diseases."This timely high-level event provides us with an ideal platform to share views, information, ideas and experiences, to come up with remedial proposals and to forge effective collaborative partnerships in the implementation of realistic but effective health development programs in common areas of concern pertaining to the non-communicable diseases," Niknam said.He explained that Iran is implementing a series of programs in order to reduce the frequency and impacts of NCDs."As part of these programs I would like to mention prevention and control of common NCDs risk factors, imposition of taxes to curtail unhealthy habits such as tobacco consumption, execution of mass public information and educational campaigns, fostering food industry regulations, screening of blood pressure levels and high glucosemia," he said.Iran has created a Non-Communicable Diseases Risk Factor Surveillance System, according to Niknam. This system, in place since 2004, has conducted six large-scale surveys to gather information helpful to public health."Further, comprehensive cumulative national data has been compiled based on age, sex and location to facilitate effective monitoring and implementation of policies geared towards control and prevention of NCDs," Niknam said.Iran is conducting many other integrated NCD control and prevention programs, such as, to name a few, a Cardiovascular Diseases Control Program for rural areas; a National Cancer Control Program focusing on breast and colorectal cancers; and a Diabetes Control and Prevention Program that targets both rural and urban areas.Niknam ended his statement by noting that Iran has held regional consultations on the NCD issue."I would like to conclude my remarks by mentioning that as a sign of its commitment to promote regional and international cooperation, the Islamic Republic of Iran hosted on 25-26 October 2010 in Tehran the first regional meeting of a series of the regional consultations held by WHO (World Health Organization) on the prevention and control of NCDs," he said. "In our understanding, only through closer and meaningful collaboration at all levels, especially in areas such as legislation, resource mobilization and information and knowledge sharing, we may success in our endeavor to prevent and combat NCDs."

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