鹤壁高中补习学校靠谱的价格(焦作中学补习班专业升学率) (今日更新中)

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.

SUVA, Sept. 21 (Xinhua) -- The Secretariat of the Pacific Community (SPC) stressed on Wednesday that sustainable use and management of forests and tree resources will remain its important focus for the foreseeable future.Sairusi Bulai, a forestry team coordinator of SPC's Land Resources Division (LRD) told a regional workshop currently underway in Fiji's western tourist city of Nadi that "our main issue was and continues to be the lack of adequate resources to enable countries to effectively implement sustainable forest management.""Therefore, we are very fortunate that we have this opportunity to discuss findings and recommendations of the mission, which the UN-REDD Program has undertaken in the Pacific earlier this year," he added.REDD+ is a new international mechanism to compensate developing countries for reducing their rate of deforestation and forest degradation and increasing their carbon stocks.Developing countries participate on a voluntary basis. They provide technical and financial assistance to enable eligible countries to meet the requirements for future participation. Once a country begins participating, it receives compensation for its verified reduction in carbon emission from forest activities.The UN-REDD Program is a collaborative partnership of the United Nations Development Program (UNDP), the United Nations Environment Program (UNEP) and the Food and Agriculture Organization (FAO) to support countries in the preparation of this mechanism.Bulai encouraged participants to take advantage of the excellent opportunity to discuss REDD+ experiences in the region and to link up with the experts in attendance.REDD+ gives an excellent opportunity to create better awareness and understanding amongst all stakeholders, including resource owners, so that informed decisions are made to avoid exploitation, he said.Bulai, meanwhile, stressed on the critical importance of multi- sectoral as well as multi-stakeholder based approaches to forest management to effectively reduce deforestation and forest degradation.

RAMALLAH, Aug. 26 (Xinhua) -- China's special envoy to the Middle East, Wu Sike, said here Friday that his country fully supports the Palestinians' right to establish an independent state in a balanced manner and through peace talks."China supports the Palestinian people and their cause. We also support the Palestinians to get the United Nations recognition of a Palestinian state on the lands occupied in 1967 with Jerusalem as capital," he told Xinhua in Ramallah.The envoy said peace talks with Israel are the best way to reach a settlement, adding that gaining UN recognition is not an alternative to peace negotiations.China supports a two-state solution -- Israel and an independent Palestinian state living side-by-side in peace and security, he said, noting that he believes the current developments in the Middle East have a positive impact on the Palestinian cause."The Middle East witnesses many changes. People have many chances to participate in political life. The Palestinian cause is a main issue that attracts the attention of the Arab people," he said."The recent meeting of the Arab League Peace Initiative Follow- Up Committee in Qatar assures the Arabs' support to the Palestinians' bid for full UN membership," he said. "This will help the Palestinians gain more international support."The Palestinians say they will approach the UN in September to get full membership of the world body as peace talks with Israel have long been deadlocked, a move disapproved by Israel and the United States.Wu expressed his appreciation of the reconciliation deal signed between Palestinian National Authority President Mahmoud Abbas' Fatah party and Hamas movements in Cairo in May."This move will help the Palestinians to have more countries on their side," he said.Wu said his Middle East tour was taking place at an important moment as the region is witnessing crucial changes, stressing that China respects the choices of the peoples."The Arab peoples are able to make their own decisions toward development," said the envoy.He also said the ties between China and the Arab countries are based on strong foundations, regardless of the changes taking place in the region.Wu met with Palestinian President Mahmoud Abbas and other officials Tuesday, the first day of his ongoing Middle East tour.This was Wu's second visit to Palestinian territories this year, after which he will travel on to Israel, Egypt and France.

WASHINGTON, June 6 (Xinhua) -- Women who have higher levels of the appetite-controlling hormone leptin have fewer symptoms of depression, and this apparent inverse relationship is not related to body mass index (BMI), a new study finds. The results were presented Monday at The Endocrine Society's 93rd Annual Meeting in Boston, the United States."Animal data suggest that leptin may reduce anxiety and improve depression. Our study in women suggests that leptin may indeed have antidepressant qualities," said the study's lead author, Elizabeth Lawson, of Massachusetts General Hospital and Harvard Medical School in Boston.Leptin, the product of fat cells, signals satiety, or fullness. It is low in thin women and high in obese women, according to Lawson. She also said there is an increased prevalence of anxiety and depression in certain conditions in which leptin levels are typically low. These include the eating disorder anorexia nervosa, in which there is abnormally low weight and body fat, and functional hypothalamic amenorrhea, in which women have stopped menstruating despite having normal weight."It is unknown whether low leptin levels contribute to the development of mood disorders in these women," Lawson said.She and her co-workers studied the relationship between leptin levels and symptoms of anxiety and depression in 64 women. Fifteen of the women had anorexia nervosa, 12 were normal weight with hypothalamic amenorrhea, 20 were normal weight and in good health, and 17 were overweight or obese but still healthy.All subjects were asked questions to assess symptoms of depression and anxiety, with high scores indicating more symptoms. Besides measuring leptin levels in the blood, the researchers assessed the women's BMI, a measure of weight for height.The relationship between leptin and depression symptoms was independent of BMI. This finding indicates that leptin may mediate symptoms of depression and that this effect is not a function of low weight, Lawson said."Further research administering leptin to humans will be important in understanding whether this hormone has a potential role in the treatment of depression," she said.

BEIJING, Sept. 14 (Xinhuanet) -- Facebook unveiled a new feature called "smart lists" on Tuesday, giving its users an easier way to share photos, posts and updates with smaller groups of friends.The new function, which commences on Wednesday, borrows from the success of the Circles feature of Google+, which allows users to categorize friends into groups.With the new feature, Facebook can automatically put your friends into groups, with the first four being work, school, family and city, based on the information of colleges, workplaces and geographic locations in users' profiles.The feature is optional to use, and the lists are customizable."This is really something we have been working on for four years," Facebook director of product management Blake Ross told AFP, adding "We think this is the way people will make lists going forward."In the meantime, the social networking site has also come up with "close friends" and "acquaintances" options.People can read the updates of their "close friends" more prominently in their news feed and just big news of their "acquaintances", according to Naomi Gleit, the director of product at Facebook who worked on the new feature.

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