science.docx

1、science高龄O型血女性受孕较困难文章来源：未知 文章作者：meng 发布时间：2010-10-30 00:51 字体： 大 中 小 进入论坛 (单词翻译:双击或拖选) 美国一项新研究发现，随着年龄的增加，O型血的女性受孕会更困难，这是首个有关血型会影响女性受孕几率的研究。Women with blood type O could have more trouble conceiving（怀孕，构思） as they age, an American survey claims.The study is the first to suggest that a womans blood gr

2、oup could influence her chances of getting pregnant.Researchers who tested a group of women seeking fertility treatment found those with the blood type O appeared to have a lower egg count and poorer egg quality than others.By contrast those with blood type A seemed to have more and better quality e

3、ggs.The findings could lead to women with type O blood being advised to try for a baby earlier, but experts said more research was needed before such a step was taken.The blood groups O and A are the two most common in the British population: some 44 per cent are type O and 42 per cent are type A.Th

4、e lead author, Dr Edward Nejat, of the department of obstetrics（产科学，助产术） and gynaecology（妇科医学） at the Albert Einstein College of Medicine in New York, said his findings were based on women having fertility treatment at the Yale University IVF programme and the Montefiore Institute in New York.He is

5、presenting his findings tomorrow at the annual American Society for Reproductive Medicine (ASRM) conference in Denver.The study of 560 women, whose average age was just under 35, found that those with blood type O were more likely to have higher levels of follicle（卵泡） stimulating hormone (FSH) than

6、those with type A.Fertility experts regard a high FSH level as a key indicator of having a low egg count. FSH is produced by the body to stimulate the follicles in the ovaries that produce eggs.As a womans ovaries run out of eggs in her 30s and 40s, production therefore has to be stepped up to encou

7、rage more eggs. The presence of high levels of FSH indicates lower numbers of eggs.The study found that women with blood type O were twice as likely to have an FSH level above 10 regarded as the threshold between normal and raised levels as those in any other blood group.People with blood group A ca

8、rry the A antigen（抗原） , a protein on the cell surface, that is absent in people with O type.Dr Nejat said: Those with blood type O were twice as likely to have an FSH level over 10 than those with blood types other than O. We found that women with the A blood group gene were protected from this effe

9、ct.Susan Seenan, of Infertility Network UK, welcomed the study. Anything that might help couples avoid having fertility treatment has got to be good news, she said.Tony Rutherford, the chairman of the British Fertility Society, said the research was interesting.But he said a study needed to be carri

10、ed out among the general population, not just those who had gone for help with fertility problems.中国研制出世界最强超级计算机文章来源：未知 文章作者：meng 发布时间：2010-10-29 06:31 China has claimed the top spot on the list of the worlds supercomputers.中国宣称登顶世界超级计算机之排行榜。The Tianhe-1A supercomputer is about 50% faster than its c

11、losest rival. The title has gone to Chinas Tianhe-1A supercomputer that is capable of carrying out more than 2.5 thousand trillion calculations a second.To reach such high speeds the machine draws on more than 7,000 graphics（制图学） processors and 14,000 Intel chips.The claim to be the fastest machine

12、on the planet has been ratified（批准） by the Top 500 Organisation which maintains a list of the most powerful machines.High powerChinas Tianhe-1A (Milky Way) has taken over the top spot from Americas XT5 Jaguar at the Oak Ridge National Laboratory (ORNL) in Tennessee that can carry out only 1.75 petaf

13、lops per second. One petaflop is the equivalent of 1,000 trillion calculations per second.The news about the machine broke just before the publication of the biennial（两年一次的） Top 500 Supercomputer list which ranks the worlds most powerful machines.Prof Jack Dongarra from the University of Tennessee,

14、one of the computer scientists who helps to compile（编制，编辑） the list, said Chinas claim was legitimate.This is all true, he told BBC News. I was in China last week and talked with the designers, saw the system, and verified the results.He added: I would say its 47% faster than the Oak Ridge National

15、Laboratorys machine, 1.7 Pflops (ORNL system) to 2.5 Pflops (Chinese system).Tianhe-1A is unusual in that it unites thousands of Intel processors with thousands of graphics cards made by Nvidia.The chips inside graphics cards are typically made up of small arithmetical（算术的） units that can carry out

16、simple sums very quickly. By contrast, Intel chips are typically used to carry out more complicated mathematical operations.The machine houses its processors in more than 100 fridge-sized cabinets and together these weigh more than 155 tonnes.Based in Chinas National Center for Supercomputing in the

17、 city of Tianjin, the computer has already started to do work for the local weather service and the National Offshore Oil Corporation.苹果发布新MacBook Air笔记本文章来源：未知 文章作者：meng 发布时间：2010-10-21 06:53 字体： 大 中 小 进入论坛 Apple is cashing in on the popularity of its iPhone and iPad to boost demand for its oldest

18、product, the Macintosh. 苹果利用其iPhone和iPad广受欢迎的机会扩大其笔记本Macintosh的公众需求。The MacBook Air is 0.11 inches thick at its thinnest point The company launched a revamped（修订的） MacBook Air at an event dubbed（被称为） Back to the Mac at its Cupertino headquarters.The computer is seen as a marriage of what Apple has l

19、earned from desktop computing and mobile devices. Like the iPad, the Air will have no hard drive and rely on flash memory.Its like nothing weve ever created before, said Apple boss Steve Jobs.We see these as the next generation of MacBooks. We think all notebooks are going to be like this one day. W

20、eve been inspired by some of the work we have done on iOS and want to bring them back to the Mac, said Mr Jobs.Analysts said the new product sends out a clear signal to the industry.This is a strong reminder to everyone out there that Apple is still in the PC business, said Michael Gartenberg, resea

21、rch director with Gartner.They are still making a lot of money in the PC business and if anyone thinks they are getting out of that business given the money they are making they are very mistaken.On saleThe new MacBook Air is 0.11 inches thick at its thinnest point. Apple said the computers battery

22、life lets users surf the web for seven hours. In standby mode, the battery can last 30 days.Models start at $999 and are now shipping.In an overview, Apple said the Macintosh accounted for a third of the companys revenue or $22bn in the fiscal year（财政年度） that has just ended.They sold 13.7 million Ma

23、cs last year, which is three times the sales they had in 2005. The firm also cited research figures that showed Apple now controls 20.7% of the US consumer market and accounts for one in every five computers sold.The Mac company, if it were a standalone（单独的） company, and we have no plans to do that,

24、 would be 110 on the Fortune 500 list, said Tim Cook, Apples chief technology officer.Other featuresApple also unveiled a new version of the Macintosh operating system, called Lion, to be released next summer.The new OS is designed to take advantage of some of the features of the mobile iOS by bring

25、ing them to the desktop.Lion brings many of the best ideas from the iPad back to the Mac, plus some fresh new ones, said Mr Jobs.The company revealed that Macs will soon have an application store mirroring the one that exists for the iPhone and the iPad.A launchpad will make it easy to organise and

26、launch apps in the new version of the operating system.The store will open in 90 days.FaceTime, which debuted（初次登台） on the iPhone 4 this summer, will bring video-chatting to Macs.Also being updated is Apples flagship software suite iLife. The new edition includes updates to iPhotos, iMovie, GarageBa

27、nd, iDVD and iWeb.With the refreshed iPhoto feature, it will be easier for users to email photos and turn pictures into books and cards.人体“圆润型”基因被发现文章来源：未知 文章作者：meng 发布时间：2010-10-11 07:21 字体： 大 中 小 进入论坛 (单词翻译:双击或拖选) The parts of our DNA which may influence body shape, including the classic apple or

28、pear shape in women, have been revealed.人体DNA的某些部分可能会影响到体型，例如女士经典的“苹果型”“圆润型”体型。日前这些部分已被发现。The genes help determine body shape A UK study in Nature Genetics found the locations of 13 genes which may play a role, with a stronger effect in women.Where body fat lies may affect diabetes（糖尿病） and heart di

29、sease risk, so the results could shed light on those diseases.A British Heart Foundation spokesman said the findings could lead to new dietary advice or medicines.It is known that men and women who carry more fat around their waists compared with their bottoms and thighs（大腿） are more prone to diabet

30、es and heart disease - but the reason why fat accumulates in different places is far less clear.The scientists, led by researchers at Oxford University and the Medical Research Council, looked at the genetic code of more than 77,000 people, looking for genetic regions which could be linked to differ

31、ences in body fat distribution.Although the 13 locations highlighted probably only account for a tiny fraction of the variation in the ratio between waist and hip, they are more likely to point towards the underlying（潜在的，根本的） body mechanisms which control fat storage.Genes known to be involved in co

32、ntrolling cholesterol（胆固醇） , insulin（胰岛素） , and insulin resistance - linked to the development of diabetes - fall within the 13 regions.Stepping stoneThe fact that the effect of genes in these locations may be stronger for women than for men also intrigues（激起兴趣） the researchers.Dr Cecilia Lindgren, of the Wellcome Trust Centre for Human Genetics at Oxford, said: By finding genes that have an important rol