广元阳痿治疗的男科医院(割包皮手术医院广元) (今日更新中)

WELLINGTON, June 10 (Xinhua) -- Scientists have uncovered an almost complete picture of the remains of a geological formation that was one of the great wonders of the 19th Century world before it was covered in ash and water during a volcanic eruption.Scientists from New Zealand and the United States said Friday they had discovered the White Terraces, half of the famous Pink and White Terraces in the central North Island's Lake Rotomahana.The same group of scientists found the remnants of the pink half of the former world-famous tourist attraction on the lake floor in January.The Pink and White Terraces were buried by the eruption of Mount Tarawera 125 years ago on 10 June 1886. The two sets of cascading silica terraces were separated by several hundred metres.The two formerly glistening terraces were formed on the shores of the lake, where the silica rich waters were warmed by the magma beneath.In the late 19th Century, the cascading terraces attracted people from all over the world. The White Terraces were the larger and stretched to a height of 30 meters, forming a 240-meter face. Visitors could walk up to a crater platform where they could bathe in the clear blue waters in naturally-formed basins up to three meters deep.Project Leader Cornel de Ronde, of New Zealand's GNS Science geosciences research institute, said the sonar images from Lake Rotomahana showed the lake floor was covered overwhelmingly by soft sediment and mud.The side-scan sonar data of the lake floor was collected on the last day of the 10-day project at Lake Rotomahana during the southern summer, but was analyzed using new software, which became available after the data collection had finished.The scientists found the sonar data contained images of hard, crescent-shaped structures on the lake bed in a similar location to where the White Terraces were before the eruption of 1886.The structures were about 60 meters below the surface, a similar depth to the Pink Terraces found in January. The lake is about 122 meters deep at its deepest point."The two places on the lake floor where we encountered hard, up- standing crescent-shaped features correspond to the locations of the Pink and White Terraces before the Tarawera eruption," de Ronde said."The sonar image that appears to show part of the White Terraces came to light after the project had finished. It shows a horizontal segment of terraces over 100 meters long, although we don't know which part of the terraces it is."The rounded terrace edges are standing up from the lake floor by about a meter in some places. The sonar images of both sets of terraces are strikingly similar."Scientists managed to capture several color photographs of part of the Pink Terraces in January, but they did not lower an underwater camera over the White Terraces location during the project as they were unaware of what the sonar data was showing at the time.The fate of the remaining sections of the Pink and White Terraces was unclear, said a statement from GNS. "They might have been destroyed in the eruption. Alternatively, they could be lying under thick sediment, which is impenetrable to sonar signals sent out by the two autonomous underwater vehicles (AUVs) used in the survey."De Ronde said finding remnants of both sets of terraces was a remarkable outcome for the project."The project team was absolutely thrilled in January when we realised our AUVs had detected remnants of the Pink Terraces. Finding part of what we believe is the White Terraces as well has been surprising and very satisfying."The original aim of the project at Lake Rotomahana was to map the lake floor and investigate the extensive geothermal system under the lake and how it evolved from an on-land geothermal system to a submerged one. Anything else was a bonus," de Ronde said."It's gratifying to be part of a science project that can answer a century-old mystery about the fate of the Pink and White Terraces."De Ronde said the announcement of the find was timed to coincide with the 125th anniversary of Tarawera's eruption.The 10-day project was a collaboration involving GNS Science, Woods Hole Oceanographic Institution in Massachusetts, Lamont- Doherty Earth Observatory at Columbia University in New York, the National Oceanic and Atmospheric Administration in Seattle, and New Zealand's University of Waikato.

New York, Sept. 23 (Xinhua) -- A Chinese scientist was presented a prestigious U.S. award on Friday for the discovery of artemisinin, a drug therapy for malaria that has saved millions of lives across the globe, especially in the developing world. Pharmacologist Tu Youyou, 81, became the first scientist on the Chinese mainland to win Lasker Award, known as "America's Nobels" for their knack of gaining future recognition by the Nobel committee.Tu, a scientist at the China Academy of Chinese Medical Sciences in Beijing, pioneered a new approach to malaria treatment that has benefited hundreds of millions of people and promises to benefit many times more. By applying modern techniques and rigor to a heritage provided by 5000 years of Chinese traditional practitioners, she has delivered its riches into the 21st century."Not often in the history of clinical medicine can we celebrate a discovery that has eased the pain and distress of hundreds of millions of people and saved the lives of countless numbers of people, particularly children, in over 100 countries," Lucy Shapiro, a member of the award jury and professor of Stanford University, said while describing Tu' s discovery.Shapiro said the discovery, chemical identification, and validation of artemisinin, a highly effective anti-malarial drug, is largely due to the "scientific insight, vision and dogged determination" of Professor Tu and her team. She thought Professor Tu's work has provided the world with arguably the most important pharmaceutical intervention in the last half century."The discovery of artemisinin is a gift to mankind from traditional Chinese medicine," Tu said while receiving the award. "Continuous exploration and development of traditional medicine will, without doubt, bring more medicines to the world."

BEIJING, Aug. 2 (Xinhuanet) -- The first close-up pictures of the asteroid Vesta, a protoplanet that dates back to the early days of the solar system, were revealed Monday by NASA scientists.The images were taken by the U.S. space agency's Dawn robotic probe, which is two weeks into a planned year-long survey of the second largest object in the main asteroid belt, located between Mars and Jupiter.About twice the size of California, Vesta is second in size only to Ceres, Dawn's next target and, along with Pluto, one of just five known dwarf planets. NASA is spending 466 million dollars to explore Vesta and Ceres during the course of a 10-year mission.Images from Dawn show Vesta a surprisingly diverse terrain and several unexplained geologic features. Chaotic terrain near the south pole is dominated by a towering central peak and huge ripple-like grooves stretching around its equatorial belt. Bright spots, dark pits and craters are filled with unexplained streaks of black and white debris. Terrain north of the grooves is much more heavily cratered.Scientists believe Vesta grew from a clump of gas and dust left over after the sun's birth some 4.65 billion years ago, a supernova explosion, which added radioactive materials to the growing body.Dawn will spend about a year circling Vesta, tweaking its orbit and altitude using an innovative technology called ion propulsion system, chief engineer Marc Rayman with NASA's Jet Propulsion Laboratory in California said.The ion propulsion system will enable Dawn to leave Vesta's orbit after a year of study and head off to Ceres, which is the largest object in the asteroid belt.

BRUSSELS, May 31 (Xinhua) -- Baby bottles containing the substance Bisphenol A (BPA) would have to be pulled from the shelves across the European Union (EU) starting from Wednesday, in a "milestone" move to better protect the health of EU citizens, an official said Tuesday."Due to the fact that there are uncertainties concerning the effect of the exposure of infants to Bisphenol A, the commission deemed it both necessary and appropriate to take action," said John Dalli, EU Health and Consumer Policy Commissioner."The aim is to further reduce the exposure of the most vulnerable part of our population, i.e. infants," he said.The ban, adopted in an EU directive in late January, would prohibit baby bottles containing BPA from placing on the EU market and import into the 27-member EU from June 1.Previously, the bloc had already banned the manufacture of the controversial baby bottles on March 1, and the industry has been withdrawing such products voluntarily.BPA is an organic molecule that is used in the manufacture of polycarbonate plastics, which are used to manufacture plastic materials, such as baby bottles.Traces of BPA can be released from plastic containers into the food they carry if these containers are heated at high temperatures. They may lead to early sexual development of children and could cause cancer, according to health officials.China would also prohibit the manufacture of feeding bottles containing BPA from June 1, while imports and sales of bottles containing BPA would be banned starting from Sept. 1.

BEIJING, Aug. 22 (Xinhuanet) -- Researchers have discovered how a human egg captures an incoming sperm for fertilization, paving the way to help couples suffering from infertility, according to media reports on Monday.An international team of researchers found that a sugar chain known as the sialyl-lewis-x sequence (SLeX) makes the outer coat of the egg “sticky,” which has proven to be helpful in binding the egg and the sperm.As a result, this observation has filled in a huge gap in the understanding of fertility and provides hope for ultimately helping couples who currently cannot conceive.Scientists and doctors know that a sperm identifies an egg when proteins on the head of the sperm match and bind to a series of specific sugars in the egg’s outer coating. With a successful match of proteins, the outside surfaces of the sperm and egg then bind together before merging, which is then followed by delivery of sperm’s DNA into egg.To identify this molecules, the researchers used ultra-sensitive mass-spectrometric imaging technology to observe and identify which molecules are most likely to be key in the binding process.They experimented with a range of synthesised sugars in the laboratory and found that it is SLeX that specifically binds sperm to an egg.According to the World Health Organisation, infertility affects about 15 percent of reproductive-aged couples around the world and almost one in every seven couples in Britain has problems conceiving a child for various reasons.

来源：资阳报