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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.

SAN FRANCISCO, June 15 (Xinhua) -- As social networking sites like Facebook and Twitter grow worldwide, more Internet retailers are beefing up their efforts to add social twists to their business, trying to define the idea of "social commerce" and capitalize the opportunity.On Wednesday, online auction giant eBay revealed some of the social features it is planning to launch later this year, while Copious, a San Francisco-based startup, launched its online social commerce marketplace with a slogan of "buying from and selling to people, not strangers."Copious asks users to log in through their Facebook accounts and allows buyers and sellers to see if they have friends in common in their social networking sites. Buyers can see more information about a seller and also see whether anyone in their networks has purchased, shared or commented on an item from a specific seller, rather than anonymity or simple profiles on sites like eBay and Craigslist.As for sellers, Copious has a social pricing mechanism that enables a seller to offer buyers discounts for sharing listings on Facebook and for following the seller on Copious.Jonathan Ehrlich, Copious co-founder and former Facebook head of marketing, told technology blog TechCrunch that the site is centralized around using social data as a signal to help users understand and trust other parties.According to Copious, the startup founded in January 2011 has raised two million U.S. dollars in funding from Foundation Capital, Google Ventures, Blackberry Partners Fund and a number of Silicon Valley angel investors.Also on Wednesday, Christopher Payne, vice president and head of eBay North America, delivered a keynote speech at the Internet Retailer Conference and Exhibition 2011 in San Diego, revealing some features eBay is launching during the social trend.One feature will enable users to log in their Facebook account on eBay's homepage to get product recommendations based on one's purchasing history and things they have "liked" on their Facebook page. Another feature will allow users to post multiple products on their Facebook page to get their friends' opinions and ask them to vote for the final purchase.EBay has been stepping up its social efforts, and Payne said on Wednesday that social is a top-level initiative for Internet retailers. Last month, eBay hired former Yahoo executive Don Bradford to lead its social commerce efforts. Last November, it launched Group Gifts service, enabling users to chip in to buy a gift for someone.A research by Adgregate Market in March showed that more brand websites are losing traffic to their Facebook pages. The study revealed that the "Facebook stores" of most Internet retailers are more efficient at acquiring visitors, indicating social commerce is poised to take off.Although the idea of social commerce is still new, more companies are trying to seize the opportunity in their own moves.There are many other companies taking the social commerce model. Oodle, the exclusive provider of classified ads on the Facebook Marketplace, rolled out a series of social features last December to make more money from social classifieds.In February, Payvment Inc. launched a Facebook Mall, where consumers can shop for more than 1.2 million products among 60,000 retailers in a single shopping cart.Yardsellr, which is often called "an eBay for Facebook," allows sellers to list items at fixed prices in different categories called "blocks," such as jewelry and purses. Prospective buyers can "like" the "blocks" they are interested in on the Yardsellr website or its Facebook page, and then they will get Facebook news feed if a seller has something to offer in the category.Yardsellr said 1.5 million people were following its "blocks" by late December 2010 and the number of new followers is growing by 20,000 daily.

VIENNA, Sept. 22 (Xinhua) -- Climate change and rising temperature in the long term can lead to water shortages in the Alps region, international experts warned Thursday at the Water-Scarce Final Conference in the Austrian eastern city Graz.The Alpine region originally is rich in water resources due to a large number of glaciers, spring and abundant rainfall either in summer or winter. But global warming may change this situation which has been shown in the past years that the water reserve has reduced gradually due to climate change, warned the experts.Observation data have shown a significant decrease of 25 percent in groundwater recharge in the past 100 years which has also resulted in the reduction of mountain spring.Director of the Provincial Department of Water Resources of Styria Johann Wiedner point out, in 2003, droughts occurred in the eastern part of the Alps, including the state of Styria and water shortages were also found in other regions of the Alps. He said the phenomenon was giving a warning that people "have to do something."To this end, the European Union begun a project called "Alp Water Scarce" three years ago to observe water reserves, air temperature, water temperature and water table in this region and study the relationships among them.Wiedner also admitted that there is no shortage of water at least in the short term and water supply for the local residents is totally insured.

LOS ANGELES, July 3 (Xinhua) -- Warming of the ocean's subsurface layers will melt underwater portions of the Greenland and Antarctic ice sheets faster than previously thought, increasing the sea level more than already projected, a new study suggests.The subsurface ocean layers surrounding the polar ice sheets will warm substantially as global warming progresses, according to the study led by researchers from the University of Arizona (UA).In addition to being exposed to warming air, underwater portions of the polar ice sheets and glaciers will be bathed in warming seawater, said the study appearing on the website of the American Association for the Advancement of Science (AAAS) on Sunday.The research, based on 19 state-of-the-art climate models, proposes a new mechanism by which global warming will accelerate the melting of the great ice sheets during this century and the next."To my knowledge, this study is the first to quantify and compare future ocean warming around the Greenland and the Antarctic ice sheets using an ensemble of models," said lead author Jianjun Yin, a UA assistant professor of geosciences.According to the study, the subsurface ocean along the Greenland coast could increase as much as 3.6 F (2 C) by 2100.Most previous research has focused on how increases in atmospheric temperatures would affect the ice sheets, he said."Ocean warming is very important compared to atmospheric warming because water has a much larger heat capacity than air," Yin said. "If you put an ice cube in a warm room, it will melt in several hours. But if you put an ice cube in a cup of warm water, it will disappear in just minutes."Given a mid-level increase in greenhouse gases, the researchers found the ocean layer about 650 to 1,650 feet (200 to 500 meters) below the surface would warm, on average, about 1.8 F (1 C) by 2100. Along the Greenland coast, that layer would warm twice as much, but along Antarctica would warm less, only 0.9 F (0.5 C)."No one has noticed this discrepancy before -- that the subsurface oceans surrounding Greenland and Antarctica warm very differently," Yin said.Part of the warming in the North comes from the Gulf Stream carrying warm subtropical waters north. By contrast, the Antarctic Circumpolar Current blocks some of the subtropical warmth from entering the Antarctic's coastal waters.Even so, the Antarctic ice sheet will be bathed in warming waters, according to the study.This paper adds to the evidence that sea level would rise by the end of this century by around one meter and a good deal more in succeeding centuries, the study noted.The study, "Different Magnitudes of Projected Subsurface Ocean Warming Around Greenland and Antarctica," is scheduled for the upcoming edition of Nature Geoscience later this month.

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