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BEIJING, Sept. 14 (Xinhuanet) -- Scientists had discovered the fossils of a new species of ancient carnivorous fish, National Geographic reported Monday.The newly-found ancient fish, "Laccognathus embryi", is a 1.8-meter-long predator, which was "waiting to lunge out to grab whatever was in front of it," said study co-author Ted Daeschler, a vertebrate zoologist at the Academy of Natural Sciences in Philadelphia, the U.S..It had a jaw filled with sharp teeth that were 1.5 inches long, the Journal of Vertebrate Paleontology described.The fish lived in the Devonian period, 415 to 360 million years ago, which "was a fish-eats-fish kind of world," Daeschler said. "There was a real arms race going. If you didn't have good armor on your body, you were very vulnerable.""It's not just finding the animal - it's also placing the animal in its evolutionary crucible," Daeschler added.Its closest living relative is the lungfish which can survive in the drought, scientists said.Scientists hope the finding can help in their study on the revolution of fishes as well as other species.

LOS ANGELES, June 23 (Xinhua) -- The sun and its inner planets may have formed differently than previously thought, NASA's Jet Propulsion Laboratory (JPL) said on Thursday.Data revealed differences between the sun and planets in oxygen and nitrogen, which are two of the most abundant elements in our solar system, said JPL in Pasadena, Los Angeles.Although the difference is slight, the implications could help determine how our solar system evolved, JPL said.NASA researchers drew the conclusion after analyzing samples returned by NASA's 2004 Genesis mission, according to JPL.The air on Earth contains three different kinds of oxygen atoms which are differentiated by the number of neutrons they contain. Nearly 100 percent of oxygen atoms in the solar system are composed of O-16, but there are also tiny amounts of more exotic oxygen isotopes called O-17 and O-18. Researchers studying the oxygen of Genesis samples found that the percentage of O-16 in the sun is slightly higher than on Earth or on other terrestrial planets. The other isotopes' percentages were slightly lower."We found that Earth, the moon, as well as Martian and other meteorites which are samples of asteroids, have a lower concentration of the O-16 than does the sun," said Kevin McKeegan, a Genesis co-investigator from University of California, Los Angeles (UCLA) and the lead author of one of two papers published this week in Science journal. "The implication is that we did not form out of the same solar nebula materials that created the sun -- just how and why remains to be discovered." Another paper detailed differences between the sun and planets in the element nitrogen. Like oxygen, nitrogen has one isotope, N- 14, that makes up nearly 100 percent of the atoms in the solar system, but there is also a tiny amount of N-15. Researchers studying the same samples saw that when compared to Earth's atmosphere, nitrogen in the sun and Jupiter has slightly more N-14, but 40 percent less N-15. Both the sun and Jupiter appear to have the same nitrogen composition. As is the case for oxygen, Earth and the rest of the inner solar system are very different in nitrogen."These findings show that all solar system objects including the terrestrial planets, meteorites and comets are anomalous compared to the initial composition of the nebula from which the solar system formed," said Bernard Marty, a Genesis co- investigator from Petrographic and Geochemical Research Center in Fracne and the lead author of the other new Science paper. " Understanding the cause of such a heterogeneity will impact our view on the formation of the solar system."Data were obtained from analysis of samples Genesis collected from the solar wind, or material ejected from the outer portion of the sun. This material can be thought of as a fossil of our nebula because the preponderance of scientific evidence suggests that the outer layer of our sun has not changed measurably for billions of years."The sun houses more than 99 percent of the material currently in our solar system, so it's a good idea to get to know it better, " said Genesis Principal Investigator Don Burnett of the California Institute of Technology, Pasadena, California. "While it was more challenging than expected, we have answered some important questions, and like all successful missions, generated plenty more."Genesis was launched in August 2000. The spacecraft traveled to Earth's L1 Lagrange Point about one million miles from Earth, where it remained for 886 days between 2001 and 2004, passively collecting solar-wind samples.JPL managed the Genesis mission for NASA's Science Mission Directorate, Washington. The Genesis mission was part of the Discovery Program managed at NASA's Marshall Space Flight Center in Huntsville, Alasca.

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.

BEIJING, July 19 (Xinhuanet) -- Amazon on Monday launched its Kindle textbook rental service, which allows students to rent "tens of thousands of textbooks", according to Los Angeles Times.The e-book textbook rental service will help students save as much as 80 percent on some titles.Amazon said that students can now rent textbooks from 30 to 360 days and can either rent them again or purchase them once the rental period is up."Students tell us that they enjoy the low prices we offer on new and used print textbooks. Now we're excited to offer students an option to rent Kindle textbooks and only pay for the time they need—with savings up to 80 percent off the print list price on a 30-day rental," Dave Limp, vice president of Amazon Kindle said, according to PC Magazine.Rentals can be read on Amazon's Kindle eReaders, and Kindle apps for PCs, as well as smartphones and tablet computers running Apple's iOS, Microsoft Windows Phone 7 and Google's Android operating system.Rentals also have a clear advantage over physical copies that students' notes and highlighted content will be stored in the Amazon Cloud, and can be accessed if students rent the books again or buy at a later time.

SAN FRANCISCO, Aug. 10 (Xinhua) -- Amazon on Wednesday launched Kindle Cloud Reader, a web-based app that may help the on-line retailer to sidestep Apple's App Store restrictions.In its announcement, Amazon said Kindle Could Reader uses the HTML5 web standard to let users read e-books from their Kindle library from the Safari browser or Google's Chrome browser on their desktops or tablet, including the iPad.Support for Internet Explorer, Firefox and the Blackberry Playbook will be launched later this year.The app has a button linked to the Kindle Store, which was removed recently from the Kindle apps for iPad and iPhone.The move is taken as an answer to Apple's latest App Store restrictions, which banned developers to have any external links for purchasing digital books or subscriptions in the app, unless they give Apple a 30 percent cut from the in-app sales.Besides Amazon, Barnes & Noble, Google Books and Canadian e- book seller Kobo have also altered their iPad and iPhone apps to comply with the rules.Meanwhile, publishers and retailers have been developing web- based HTML5 apps to sidestep Apple for more control, which is an approved-of technology for iOS devices.The Financial Times, Kobo and video-on-demand service Vudu have recently launched their HTML5 app to avoid paying Apple a 30 percent cut.Industry watchers said it is unknown how Apple will deal with such apps. It would be easy for Apple to disable Web apps in the iPad's Safari browser, but the company would certainly face some backlash, said tech media website CNET.

来源：资阳报