旅游  |  攻略  |  美食  |  自驾  |  团购
您的位置: 青海省旅游网 / 规划 / 新闻动态 / 青海要闻

浙江杭州市七院QQ号放心乐园萧山妇保医院做宫颈手术

来源:百度优惠    发布时间:2019年06月16日 05:17:09    编辑:admin         

Science and technology科学技术Human evolution人类的进化You look familiar 你,似曾相识Another piece of humanitys family tree is fitted into place确定另一人类谱系THE opening scene of Mel Brookss film History of the World: Part One dispenses with human origins in one line: 梅尔布鲁克斯的电影世界历史:第一部一开场就用一句台词概括了人类的起源:And the ape stood, and became man. 猿猴站立起来了,然后变成了人。Would that it were that easy for palaeontologists to sort out. 对古生物学家来说,要是真能如此解释,那也未免太容易了。The transition to humanity is generally agreed to have occurred between Australopithecus, a genus of small-brained, 人们普遍认为,人类是在南猿,bipedal primates whose most famous member is a fossil nicknamed Lucy, and the big-brained species Homo erectus. 和直立猿人之间完成人类进化过渡的。But pinning down when precisely this took place, and which of the various australopithecine species were involved, has been challenging. 但至于这段过渡期确切发生在什么时候,又属于众多南猿物种的哪一分,人们众说纷纭。Now the most human-like australopithecine found to date is clarifying things—and staking a claim to be the species from which early humans evolved.而目前发现的与人类长得最像的南猿,让一切变得清晰起来,同时,它也被确定是后来进化为早期人类的物种。Fossils of the new species, Australopithecus sediba, were discovered in 2008 in a cave in South Africa. 新发现的物种化石南猿源泉种于2008年在南非一个山洞中被发现。Initial research, led by Lee Berger of the University of the Witwatersrand, in Johannesburg, concluded that the species came too late in the fossil record to be the ancestor of the Homo lineage. 约翰内斯堡的威特沃特斯兰德大学教授Lee Berger,带领的研究团队经初步研究发现,新物种是化石史上最接近猿人谱系的祖先。This week, however, a range of new research into sediba, again led by Dr Berger, has been published in Science. 本周,科学杂志发表了 Berger士对源泉种的一系列新发现,These studies conclude that sediba did in fact predate Homo erectus and, moreover, that parts of its anatomy are surprisingly similar to modern man.称源泉种实际上要早于直立猿人,并且其结构的某些部分与现代人也极为相似。The fossils examined in the Science papers are of an adolescent boy and an adult woman. 科学杂志发表的论文研究的化石对象,一个是少年,一个是成年女子。They are well preserved, and encased in sediments that allow uncommonly precise dating. 这两具化石保存完好,由于是在沉积层出土,所以可以很精确的确定它们的年代。They lived 1.977m years ago, predating the appearance of Homo erectus by 77,000 years. 他们生活在197,7000年前,比直立猿人早出现7,7000年。The period is an especially muddled one for palaeontology, being full of fragmentary fossils that are difficult to assign either to Homo or to Australopithecus. 这段时期令古生物学家一直很迷惑不解,因为所有的化石碎片很难确定到底是属于南猿还是直立猿人。The sediba fossils, by contrast, have some of the most complete features in the early human record.相比较而言,源泉种化石具有部分早期人类最完整的特征。The new studies centre on the most telling bits of anatomy in the story of human evolution: 最新的研究把重点放在研究人类进化最有说力的结构部位:the brain, pelvis, hands and feet. 脑,骨盆,手和脚。The brain itself does not fossilise, but the inside of the cranium retains an impression of its contours. 脑部分本身是不会变成化石的,但在头盖骨内部却还保留着脑的轮廓。The researchers mapped these with high-powered X-ray beams to create a three-dimensional model of the surface of sedibas brain.研究人员借助高功率X射线,描绘出了源泉种脑表面的三维模型。They found that its size was on a par with other australopithecines, 他们发现源泉种的脑尺寸与其它南猿一样,but its shape was more like that of a human brain. 但是其形状则更像人类的大脑。Specifically, the frontal lobes, which are the seat in modern humans of higher cognitive functions such as abstract reasoning, 特别是大脑前庭部分,它使现代人具有较高的认知能力—例如抽象推理的能力,looked more humanlike in sedibas brain than they do in the brains of other australopithecines. 而相比较南猿来说,源泉种的大脑前庭更像人类。That suggests the neurological changes which gave rise to humanity may have predated the brains expansion—an event that had, hitherto, been regarded as crucial to the emergence of humans. 这表明,人类产生所依赖的大脑神经上的变化,有可能在大脑变大之前就已经出现,这也是迄今为止被认为是人类诞生的关键因素。The hands, feet and pelvis of sediba indicate that it both climbed trees and walked upright, though with a different gait from that of humans or chimpanzees. 从源泉种的手、脚和骨盆来看,源泉种既能爬树又能直立行走,但步态与人类或是猩猩有点不一样。The species may have been a toolmaker, as its hand allowed for a human-like grip. 这种物种有可能也会制作工具,因为它的手可以像人类一样抓取东西。Sedibas pelvis, an upright butterfly shape, is likewise reminiscent of the human one. 源泉种的骨盆,呈垂直蝴蝶形,同样让人看到人类骨盘的影子。It therefore sheds light on a longstanding debate: 这也使长期的争论变得清晰起来:whether it was bipedalism or giving birth to babies with large heads that drove changes in the shape of the human pelvis. 是否这种物种是用两只脚行走,或是它所生的后代头比较大,使其骨盆发生了改变,和人类的骨盆形状一样。Adult sediba had small heads, which indicates that walking upright was the advantage brought by the modern pelvis. 成年的源泉种头比较小,这也表明,南猿在骨盆进化之后,直立行走才变为可能。All of which makes sediba more similar to modern humans than are other australopithecines—and more similar, even, than Homo habilis, until now seen as one of the earliest humans. 所有这些使得源泉种比其它南猿,甚至比能人更像现代人类,直到现在有人把源泉种视为最早的人类成员之一。The consensus had been that habilis was a transitional form between Australopithecus and Homo erectus. 普遍认为,能人是介于南猿与直立猿人之间。Dr Berger posits that sediba may have evolved directly into Homo erectus, leaving habilis as an evolutionary sideline, and not even part of the genus Homo. 而Berger士认为,源泉种有可能直接进化为直立猿人,而能人却是进化过程中的一个分,甚至和源泉种不属于一个类别。Slowly, then, the origin of the strange assemblage of characters that makes a human being human is emerging. 之后,一些奇特的人类特征才开始慢慢出现。As the oracle said, the beginning of wisdom is: know thyself.正如神谕所说:智慧从认识自己开始!点击此处下载本期经济学人讲解PDF与音频字幕 /201306/244476。

Until recently, when scientists studied changes in open-ocean ecosystems, they looked at changes in the bottom of the food chain that gradually make their way to the top, like foodshortages and shifts in the ocean environment.直到最近,当科学家们在研究远洋地区生态系统的变化时,他们观察了处于食物链最底层并且在慢慢上升的变化,比如说食物短缺、海洋环境的变化。A recent study,however, suggests that more attention needs to be given totop-down influences as well.然而,最近的一项调查显示,人们还应该更多的注意自上而下的影响。For example, over the past few decades, theres been a major collapse of the populations ofharbor seals, fur seals, sea lions, and sea otters living on the coasts of western Alaska.比方说,在过去的几十年里,生活在阿拉斯加西海岸的斑海豹、海、海狮和海獭数量极具下降。Now a newstudy suggests that all this destruction can be traced back to humans overfishing sperm andbaleen whales between 1946 and 1979.现在,一项新的调查显示,所有的这些毁坏都可以归咎于人类在1946年到1979年期间过度捕捞抹香鲸和须鲸。Killer whales, who live at the top of the ocean food chain, used to prey on sperm and baleenwhales.虎鲸是在海洋食物链的最高层,它习惯于捕食抹香鲸和须鲸。When these were no longer available, the killer whales were forced to fish farther down the food chain.当虎鲸不能再捕食它们的时候,它就被迫捕食处于更下一层的食物链。First they fed on seals, which were the easiest to catch and the most nutritionallyvaluable.她们先捕食的是最容易捕捉且最有营养价值的海豹。Then, when seals became rare, the killer whales turned to sea lions.接着,当海豹变得稀少后,虎鲸便转向了海狮。When the sea lionpopulation crashed, they started fishing sea otters.而又当海狮的数量变少后,虎鲸又开始猎杀海獭了。The domino effect reaches even farther.多米诺效应又继续延伸。Without sea otters keeping sea urchins in check, their population has exploded.没了海獭约束海胆,海胆的数量变得庞大起来。And theyvedestroyed the kelp forests, and with it, the kelp forest ecosystem in southwestern Alaska.并且破坏阿拉斯加啊西南部的海藻林生态系统。Animals switching food sources can have a very serious effect on the environment.动物间交换食物来源对环境有着很严重的影响。And thatwe humans, as the ultimate predators, need to give a lot of thought to the choices we make.而作为终极捕食者,人类需要好好思考一下他们所做的选择。They may affect the food web in unintended ways.这些选择可能会以人们所不知道的方式来影响食物网。 201405/301199。

Science and technology科学技术Mining asteroids小行星采矿Going platinum小行星采矿—淘铂去Mining metals from asteroids seems a bonkers idea. But could it work?小行星采矿这想法听似疯狂,但行得通吗?CAN reality trump art? That was the question hovering over the launch on April 24th, at the Museum of Flight in Seattle, of a plan by a firm called Planetary Resources to mine metals from asteroids and bring them back to Earth.4月24日,行星资源公司在西雅图的航天物馆启动了一项计划—在小行星上采矿并将矿物带回地球。对这项计划,人们一直都在疑惑:现实能否战胜艺术?It sounds like the plot of a film by James Cameron—and, appropriately, Mr Cameron is indeed one of the companys backers.这听着就像詹姆斯卡梅隆的电影中的情节—恰好,詹姆斯卡梅隆实际上就是这家公司的赞助人之一。The team behind the firm, however, claim they are not joking.但是公司背后的团队宣称小行星采矿这事可不是在开玩笑。The companys founders are Peter Diamandis, instigator of the X Prize, awarded in 2004 to Paul Allen and Burt Rutan for the first private space flight, and Eric Anderson, another of whose companies, Space Adventures, has aly shot seven tourists into orbit.行星资源公司的创始人是X奖发起者Peter Diamandis和拥有太空探险公司的Eric Anderson。Larry Page and Eric Schmidt, respectively the chief executive and the chairman of Google, are also involved.GOOGLE的总经理Larry Page和董事长 Eric Schmidt也参与其中,So, too, is Charles Symonyi, the engineer who oversaw the creation of Microsofts Office software.曾负责监督开发微软办公软件的工程师Charles Symonyi同样是其中一分子。With a cast-list like that, it is at least polite to take them seriously.阵容如此强大,出于礼貌至少也该重视这个想法。As pies in the sky go, some asteroids do look pretty tasty.这想法虽不切实际,但有些小行星看来确实很诱人。A lot are unconsolidated piles of rubble left over from the beginning of the solar system.它们许多是由太阳系诞生时遗留下来的碎石堆成的,结构松散;Many, though, are pieces of small planets that bashed into each other over the past few billion years.但仍有很多是过去几十亿年里小行星相互碰撞产生的碎片。These, in particular, will be high on Planetary Resources shopping list because the planet-forming processes of mineral-melting and subsequent stratification into core, mantle and crust will have sorted their contents in ways that can concentrate valuable materials into exploitable ores.特别是后者将被行星资源公司优先列在其采矿清单上。因为在行星诞生时,矿物熔化之后会层化为地核、地幔、地壳;这个过程将使其中物质分门别类,令有价值的矿物浓缩成可供开采的矿石。On Earth, for example, platinum and its allied elements, though rare at the surface, are reckoned more common in the planets metal-rich core.例如在地球上,铂和铂系元素在地表上虽然罕见,但人们认为在富含金属的地核里却是较为常见的。The same was probably true of the planets shattered to make asteroids.对于那些相互碰撞后其碎片形成小行星的行星而言,情况可能同样如此。Indeed, the discovery of a layer of iridium-rich rock was the first sign geologists found of the asteroid impact that is believed to have killed the dinosaurs.实际上,地质学家们提出小行星曾撞击地球的第一个据就是发现了富含铱的岩层。人们认为恐龙就是因小行星撞击地球而灭绝的。Most asteroids dwell between the orbits of Mars and Jupiter.大部分的小行星都位于火星和木星的轨道之间。But enough of them, known as near-Earth asteroids, or NEAs, come within interplanetary spitting distance of humanity for it to be worth investigating them as sources of minerals—if, of course, that can be done economically.但近地小行星也不少,它们距离地球很近,值得勘探。当然,费用要划得来才行。First catch your hare勿谋之过早The first thing is to locate a likely prospect.首先,要找到一个可能有矿藏的小行星。At the moment, about 9,000 NEAs are known, most of them courtesy of ground-based programmes looking for bodies that might one day hit Earth.目前已探明的近地小行星约有9000颗,其中大部分是地面计划在寻找可能撞击地球的天体时探测到的。That catalogue is a good start, but Planetary Resources plans to go further.从这个范围开始寻找是很好,但行星资源公司却有更远大的计划。In 2014 it intends to launch, at a cost of a few million dollars, a set of small space telescopes whose purpose will be to seek out asteroids which are easy to get to and whose orbits return them to the vicinity of Earth often enough for the accumulated spoils of a mining operation to be downloaded at frequent intervals.该公司打算在2014年耗资数百万美元发射一组小型太空望远镜,用于寻找容易到达的、能经常回到地球附近的小行星,以便常将所采矿物送回地球。That bit should not be too difficult. But the next phase will be tougher.这一步应该不会太难,但下一步就难度更大了。In just over a decade, when a set of suitable targets has been identified, the firm plans to send a second wave of spacecraft out to take a closer look at what has been found.当该公司发现了一组适合采矿的小行星时,便计划要在短短十年多一点的时间内发送第二批宇宙飞船仔细研究一下这些小行星。This is a significantly bigger challenge than getting a few telescopes into orbit.这个挑战可比向太空中发射几个望远镜要艰巨得多。It is still, though, conceivable using existing technology.不过,利用现有的技术仍是可以实现的。It is after this that the handwaving really starts.在这之后,纸上谈兵才真正开始。Broadly, there are two ways to get the goodies back to Earth.要将所采矿物运回地球大致有两种方法。The first is to attempt to mine a large NEA in its existing orbit, dropping off a payload every time it passes by.其一是在不改变其轨道的情况下于一颗较大的小行星上采矿,在这颗小行星每次接近地球时卸下所采矿物。That is the reason for the search for asteroids with appropriate orbits.这就是为何要寻找轨道合适的小行星的原因。This approach will, however, require intelligent robots which can work by themselves for years, digging and processing the desirable material.不过,此法需要能独立工作数年的智能机器人来开采并加工有价值的矿物。The other way of doing things is for the company to retrieve smaller asteroids, put them into orbit around Earth or the moon, and then dissect them at its leisure.其二是行星资源公司改变较小的小行星的运行轨道,将其安置在环绕地球或月球的轨道上,再在有空时仔细研究之。But that limits the value of the haul and risks a catastrophic impact if something goes wrong while the asteroid is being manoeuvred.但那将减少每次采矿的量,且要承担移动小行星时出现问题而带来灾难性后果的风险。Either way, the expense involved promises to be out of this world.不论哪种方法,所需费用都一定是天价。A recent feasibility study for the Keck Institute for Space Studies reckoned that the retrieval of a single 500-tonne asteroid to the moon would cost more than .5 billion.最近,克柯太空研究所进行的一项可行性分析认为,将一颗重量为500公吨的小行星移到月球附近所耗资金将超过二十五亿美元。Earlier research suggested that, to have any chance of success, an asteroid-mining venture would need to be capitalised to the tune of 0 billion.较早前的研究指出,必须投资一千亿美元才有可能实现小行星采矿。Moreover, a host of new technologies will be required, including more-powerful solar panels, electric-ion engines, extraterrestrial mining equipment and robotic refineries.而且,还需要大量新技术,包括功率更大的太阳能电池板、电子离子引擎、太空采矿设备和自动冶炼厂。All of which can, no doubt, be done if enough money and ingenuity are applied to the project.当然,若为这个项目投入足够的资金和人才,以上种种都能实现。But the real doubt over this sort of enterprise is not the supply, but the demand. Platinum, iridium and the rest are expensive precisely because they are rare.但对于这种工程浩大的项目,人们真正质疑的并非是否有人能提供这种务,而是有没有这种需求。正因为稀有,铂、铱等矿物才价格不菲。Make them common, by digging them out of the heart of a shattered planet, and they will become cheap.若这些矿物能在一个由碎片构成的行星的地核中被开采到,它们就成了普通金属,价格也会变得便宜。The most important members of the team, then, may not be the entrepreneurs and venture capitalists who put up the drive and the money, nor the engineers who build the hardware that makes it all possible, but the economists who try to work out the effect on the price of platinum when a mountain of the stuff arrives from outer space.所以,这个团队里最重要的成员可能不是推动这项事业并参与投资的企业家和风险投资人,也不是设计实现这一目的的硬件工程师;而是当大量的铂从天外而来时,那些试图算出其对铂价冲击的经济学家。 /201402/277661。

At last, this compromised, sycophantic, creepily self-exonerating historian stands tall, brimful with pride in his Judaism, and says in a phrase I find genuinely moving—We have become the teachers of men in the greatest of things.最后,这一妥协,奉承,令人毛骨悚然,兼具自我责备之心的历史学家最终赢得了胜利,他的犹太教满怀骄傲之情,而说着一句令我真正感动的话,我们成为了男性的榜样,做出了最伟大的事情。Given the hammer blows of the Roman legions, and coming as they did after century upon century of blows from Egyptians, the Syrians and Babylonians, there would have been scant reason to suppose that the Jews would survive as a people. And yet, 2,000 years later, the Jews are still here. How. Well, one answer can be found back at the Arch of Titus, not something thats here, but something thats not.对于罗马军团的打击,就如同他们几个世纪来对埃及人,叙利亚和巴比伦人所做的一模一样,这是我们认为犹太人生存下来的理由。然而,2000年后,犹太人仍在这里。在提图斯的拱门处可以找到,这里没有什么东西留下,但绝不是空无一物。When Josephus describes the procession of loot and prisoners parades through the streets of Rome, he says, and last of all of the spoils was carried, the laws of the Jews. But where are the laws. Where are the Torah scrolls. Conspicuously, tellingly, they are absent.当约瑟夫描述掠夺和囚犯游行的队伍走在罗马的大街上,他表示最后所有的战利品是犹太人的法律。但法律在哪里。律法的卷轴在哪里。明显的是它们已经不在了。What were scrolls of law anyway. Just so many words on parchment, not really worth the time of a sculptor or the cost of the marble. But words copied, memorized, internalized, made unforgettable, will beat swords any time. You cant hold words captive. The Roman Empire has come and gone, but go into a synagogue any Saturday, and youll still hear those words.什么是法律卷轴。只是羊皮纸上的很多单词,不是雕塑家倾注的大把时间或大理石的价值。仅仅是复制,记忆,难忘,会使得剑刃折断的话语。你不能囚禁语言的奴隶。罗马帝国来去匆匆,但只要在任何一个周六进入会堂,你仍然会听到这些话。201404/291908。

Nobody likes being lonely.没人喜欢孤独。As it turns out, loneliness can be unhealthy as well. 事实明,孤独对身体健康也能造成危害。The study was done by psychologist John Cacioppo at the University of Chicago.这项研究是由芝加哥大学心理学家约翰·卡奇普完成。He had thirty three male college students and twenty one female students spend five nights in a lab where their sleep could be carefully monitored.33名男大学生及21名女大学生被测试者在一个实验室中度过5晚,而这些人的睡眠则被仔细监控。That was done by having them catch Zs while wearing a special skull-cap that had devices for measuring eye motions, head motions, and brain waves.这是通过熟睡时戴着一顶测量眼球动作,头部动作及脑电波的特殊帽子完成的结果。Why? Because different kinds of waves are generated by your brain as you sleep, and the motions of your body-especially your eyes-give information about how your sleep is going.为什么?因为大脑在你熟睡时会产生不同类型的波,而身体的运动,特别是你的眼睛,展现出你的睡眠如何的信息。Afterward, the students filled out a questionnaire describing themselves.测试之后,学生们填了一份描述自己的调查问卷。In particular Cacioppo wanted to know what their social lives were like, to see if there was any connection between your social life and how well you sleep.卡奇普想了解他们的社会生活状况,来看看社会生活与睡眠之间是否有什么联系。There was indeed a connection.确实是有联系。Everyone slept for about the same amount of time, but the volunteers who rated themselves as the loneliest were also the ones who were most likely to wake up during the night.每个人都睡了大约相同时间,但认为自己最孤独的志愿者同样也最有可能在夜晚醒来。Not only that, they stayed down in deep sleep less than other people did.不仅如此,他们的深度睡眠少于其他人。What do these findings mean?这些发现意味着什么?The researchers themselves note that it isnt clear yet which is the cart and which is the horse.研究者们自己注意到并不清楚本末。That is, does being lonely interfere with a healthful nights sleep?也就是说,孤独是否会影响健康的夜间睡眠?Or, on the other hand, do people who sleep poorly for one reason or another wind up irritable and difficult to deal with, making it harder to have friends?抑或是另一方面, 因为这样或那样原因人的睡眠很糟糕最终易怒,难以相处,最终交友困难?One way or the other, lonely feels bad-and sleep shows it, too.不管怎样,孤独的滋味不咋样,就连睡眠也表明了这点。201310/260802。

With the discovery of the Stanley plot, the privy chamber went into locked out.随着斯坦利阴谋的发现,这个小房间成了外人永远不能踏足之地。Previously, its working was transparent, but with the new security overhaul, only those who would best content the king were admitted.以前,它的工作是透明的,但是随着新的安全检修,只有那些最好的内容才能被国王认同。So at the heart of this glittering household was an institutional black hole, whose working was known only to Henry himself.所以这个表面光鲜的家族核心其实是一个由来已久的黑洞,其工作仅仅亨利本人知晓。Inside the privy chamber, things were changing.在小私室内,一切都发生了改变。Henry was obsessed with control, especially when it came to money.亨利痴迷于控权,特别是提到钱的时候。The remit of his privy chamber treasure was expanding.他的职权范围之内的小私室财宝被扩大。These books are chamber accounts.这些书是皇室的账目。They are books of payments and whats interesting about these books is that they represent Henrys very personal control of finance.这是账单册而且关于这些书有趣的地方是,它们代表亨利非常个人的财务控制。These account books are brought to him, and he would look down everything and he would sign it at the bottom.这些帐册都会呈给亨利,他会仔细浏览一切,然后在最底下签字。We have everything from wages for trumpeters, for barbers, queens ministrants, the princes trumpeters, falcons bought from Hungary.我们已经掌握了从号手,理发师,女王的侍从,王子的号手,从匈牙利购买回猎鹰的薪金。Falcons bought from Hungary, brilliant.从匈牙利购买回的猎鹰,太棒了。Its quite a journey.那段旅途可真够漫长的。Brilliant.非常棒。Historian Sean Curriham has been studying Henrys account books.历史学家肖恩?克里姆一直在研究亨利的帐簿。This one shows money coming directly to Henrys personal coffers, and these pages are written by Henry himself.这一条目显示钱直接送入亨利的个人保险库,而这几页是亨利自己签字。He loved this entry in particular.他尤其喜爱这一条目。He had many delivered in old weighty crowns.他运送了许多旧的王冠。You can sense him weighing in his hand.你可以感觉到他在自己手里掂分量的情景。Thats right.是的。Picking his weighty crown.挑选他沉重的。Oh, thats good.哦,那很好。And then I like these good crowns.我喜欢这些好的王冠。These are some good crowns we have here.这些都是一些我们这里好的王冠。 201311/264921。

Science and technology科学技术Epigenetics and health表观遗传学与健康Grandmas curse祖母的诅咒Some of the effects of smoking may be passed from grandmother to grandchild祖母吸烟产生的影响可以会遗传至孙子或孙女Think of your grandchildren!想想你的孙辈吧!ONE of biologys hottest topics is epigenetics.当今生物学最热的话题之一是表观遗传学,The term itself covers a multitude of sins.这个术语本身就涵盖了许多宗罪。Strictly speaking, it refers to the regulation of gene expression by the chemical modification of DNA, or of the histone proteins in which DNA is usually wrapped.严格来说,表观遗传学研究的是DNA或含有DNA的组蛋白化学改性中的基因表达调控现象。This modification is either the addition of methyl groups to the DNA or of acetyl groups to the histones.这种改性或者是甲基增至DNA中,或者是乙酰基增加到组蛋白中。Methylation switches genes off.甲基化作用关闭基因,Acetylation switches them on.乙酰化作用启动基因。Since, in a multicellular organism, different cells need different genes to be active, such regulation is vital.由于在多细胞有机体中,不同的细胞需要借助不同的基因以激活自身,所以这种调控至关重要。What has got a lot of people excited, though, is the idea that epigenetic switches might be transmitted down the generations.但令人兴奋的是,有观点认为,表观遗传现象中的基因表达调控功能有可能世代相传。Some see this as contrary to Darwinism, since it would permit characteristics acquired during an organisms lifetime to be passed on to its offspring, as suggested by a rival theory of evolution put forward by Jean-Baptiste Lamarck.有些人将之视为对达尔文学说的反,因为这将允许有机体存活期间所获得的特征遗传给后代,正如法国著名生物学家让巴蒂斯特拉马克所提出的与进化论相对的学说。This is an exaggeration.这种想法有些夸张了。The DNA sequence itself is not being permanently altered.基因序列不会一直变化,Even those epigenetic changes that are inherited seem to be subsequently reversible.甚至那些表观遗传学意义上的变化遗传给下一代后,似乎仍然存在可逆性。But the idea that acquired characteristics can be inherited at all is still an important and novel one, and a worrying example of the phenomenon has been published this week in BioMed Central Medicine.但是,因表观遗传现象所获得的特征完全可以遗传的观点仍然新颖且重要。本周,BioMed Central Medicine刊出了一项研究,可例这一现象,其结果令人担忧。The study in question, by Virender Rehan of the Los Angeles Biomedical Research Institute, and his colleagues, was of the intergenerational effects of nicotine.该项研究是由洛杉矶生物医学研究所的Virender Rehan和他的同事们开展的,研究的是尼古丁的代际影响。It was done in rats, but a rats physiology is sufficiently similar to a humans to suspect the same thing may be true in Homo sapiens.研究人员虽然在大鼠身上进行实验,但因为大鼠的生理机能与人类十分相像,所以研究人员怀疑对于大鼠的研究结果可能同样适用于智人。In a nutshell, Dr Rehan showed that if pregnant rats are exposed to nicotine, not only will their offspring develop the asthma induced by this drug, so will the offspring of those offspring.简而言之,Rehan士想说明的是,如果大鼠怀时接触尼古丁,不仅下一代会因此患上哮喘,第三代也会深受其害。Dr Rehan and his team injected their rats with nicotine when they were six days pregnant.Rehan士和他的团队在大鼠怀的第六天为其注射尼古丁。They then allowed them to give birth and raised the pups to the age of three weeks, before some were examined.大鼠的后代出生后,由母鼠养育三周。The rest were allowed to mature and breed, and their own offspring were similarly examined.然后研究人员选取一部分后代进行检查,其余的第二代大鼠继续生长繁殖,最后研究人员对第三代大鼠进行类似的检验。There was, however, no further administration of nicotine.但是,第二代大鼠在妊娠期间,不再被注射尼古丁。The pups of the treated mothers had asthmatic lungs.检测发现,被注射尼古丁的母鼠所繁殖的第二代大鼠肺部有哮喘病变。The organs airways were constricted,大鼠肺部的气道处于收缩状态。and molecular analysis showed abnormally high levels of fibronectin and collagen—which would stiffen the lung tissue—and also high levels of receptor molecules for nicotine.经过分子分析发现,大鼠肺部的纤维连接蛋白和胶原蛋白含量异常升高,这将导致肺组织硬化;同时尼古丁受体分子增加。That was expected, since the developing embryos were exposed to the nicotine when their mothers were treated.结果表明,母鼠被注射尼古丁后,其后代在胚胎发育时期就会受尼古丁的影响,这一结果正如预期。However, when the team did similar tests on the grand-offspring of the treated mothers, they got similar results.但是,当研究团队对第三代大鼠进行类似检查时,发现了同样的情况,Those grand-offspring had not been exposed to nicotine.即使这些第三代大鼠并没有接触尼古丁。The cause of the grand-offsprings asthma, Dr Rehan believes, is epigenetic modification.Rehan士认为,第三代大鼠的哮喘是表观遗传中的改性现象。Nicotine is not only affecting lung cells, but also affecting sex cells in ways that cause the lungs which ultimately develop from those cells to express their genes in the same abnormal ways.尼古丁不仅侵袭肺部细胞,还会影响生殖细胞,使得生殖细胞在发育器官时,在肺部异常表达基因,导致新发育的肺部同样受到尼古丁的不良影响。Exactly what those epigenetic changes are is hard to track down.表观遗传现象具体引起了哪种变化,目前难以获知。The team have started looking, but could find no clear pattern except that one form of nicotine-induced acetylation, that of H3 histones, could be blocked by a molecule called RGZ.研究团队已经开始研究这一问题,但目前只研究出一种明确的模式:尼古丁会引起H3组蛋白的乙酰化,This molecule is also known to protect lungs against the asthma-causing effects of nicotine.进而导致一种叫做RGZ的分子受到抑制,而目前已知RGZ分子可以保护肺脏,使其免受由尼古丁引起的哮喘。That suggests it is the acetylation of H3 histones rather than the methylation of DNA itself that is creating the effect.这表明由尼古丁引起的哮喘是源于H3组蛋白的乙酰化,而非DNA自身的甲基化作用。Which crucial genes these histones surround remains obscure.研究团队目前没有研究出这些受影响的组蛋白包含着哪些关键基因,Nor have the team yet found out whether the epigenetic effect they have discovered reaches further than grand-offspring.也没有发现表观遗传的影响是否会延续至第三代以下的后代。If it does, though, it suggests that epigenetics really might act like the biblical curse:然而,如果有研究表明后生效应会世代相传的话,这就表明表观遗传现象真真是有如圣经上的诅咒:that the sins of the fathers will be visited on the sons, even unto the third and fourth generations.父辈的罪孽,会降罪至他们的下一代身上,甚至会延续至第三代或者第四代。 /201401/271825。

The South China Sea南海Not the usual drill非一般钻井Tensions mount dangerously in contested waters争议水域局势紧张BARACK OBAMAS tour of four countries in Asia late last month was supposed to reassure Americas friends of its commitment to the region, and to deter China from provocations in its many territorial disputes. In the South China Sea, at least, the tactic has not worked. Chinas quarrel with Vietnam, which had been dormant in recent months, flared up dangerously this week. And a new front opened in Chinas continuing tussle with the Philippines over different parts of the sea.奥巴马上月末访问亚洲四国,本应令盟友对其“重返亚洲”的承诺安心,并阻止中国挑起其诸多领土争端。但至少在南海,这个战略不起作用。中国与越南的纠纷缓和数月后,本周再度剑拔弩张。此外,中国与菲律宾又因持续不断的主权争议另一海域发生新冲突。Vietnam first. China sent its new billion rig, the Haiyang Shiyou 981, to drill for oil in waters that Vietnam regards as inside the exclusive economic zone (EEZ) it is entitled to under the international law of the sea. Vietnam demanded that the rig be withdrawn and sent nearly 30 coastguard vessels to try to stop it starting work. A protective Chinese flotilla repulsed them, ramming one and firing water cannon at others. China has declared a three-mile exclusion zone around the rig, larger than is normal.越南首当其冲。中国运送新的钻井平台“海洋石油981”进行海上石油钻探,平台价值10亿美元。越南认为中方作业区域位于其依国际海事法拥有的专属经济区内,要求中方撤离钻井平台,并派出近30艘海警船试图制止中方再度作业。中国护卫舰队驱逐了越方海警船,撞击一艘并向其余船只发射水炮。此前中方宣布“海洋石油981”钻井平台半径3海里范围为禁航区,这大于正常值。It insists the rig is operating in its own waters. It appears to claim that the area is within the EEZ attached to an island chain it controls, which China calls Xisha and the Vietnamese Hoang Sa. The islands, the Paracels in English, have been occupied by China since 1974, when it drove out the former South Vietnamese regime. Vietnam still regards them as part of its territory.中方坚持钻井平台的作业区完全位于本国海域,声称这片区域在其专属经济区内,连接着由中方控制的岛链(中国称之为西沙群岛,越南则称黄沙群岛)。这片岛链英语名称为Paracel,中国于1974年赶走岛上的越南政权后便占领了这里。但是越南仍视之为自己的领土。As always, Chinas claim is hazy. It produces maps with a vast U-shaped area covering almost the entire South China Sea, enclosed in a “nine-dash line”, which it says gives it historic rights to the land inside. This uncertainty has created tension in various parts of the sea, where the Philippines, Malaysia, Brunei and Taiwan also have claims. The dispute with the Philippines is the most active. That, too, intensified this week when the Philippines arrested 15 Chinese fishermen for poaching hundreds of endangered turtles in what it sees as its own waters.中国的主张一如既往的含糊。它制作地图时划出一片巨大的U型地带,用九段虚线将几乎整个南海划在国土范围内,并称自古以来对里面的土地拥有主权。这个不明确性在各海域形成紧张气氛,包括菲律宾、马来西亚、文莱与台湾等国家和地区。其中与菲律宾的冲突最频繁。本周菲律宾扣留了15名中国渔民,理由是这些渔民在菲律宾视之为领海的地方偷捕濒危海龟,紧张局势再度升级。Mr Obamas trip was marked by a beefing-up of Americas security ties with the Philippines, but not by an explicit American commitment to back it in the South China Sea. Vietnam is not an American ally, although relations have warmed in recent years, partly because of Vietnams fear of China. America has condemned Chinas “provocative” drilling plans but may prove powerless to thwart them. That could undo whatever progress Mr Obama made on the reassurance front.奥巴马此行被认为加强了美国与菲律宾的安全关系,而非美国重返南海的明确承诺。尽管近年美越关系好转,但越南并不是美国的盟友。部分原因是越南对中国的担心。美国谴责了中国的“挑衅性”钻探计划,但或许无法阻止该计划实行。那可能使得奥巴马在安抚盟友方面取得的进展功亏一篑。 内容来自:201406/306097。

From fluvaccines to tetanus boosters, injections are amust in modern medicine.从流感疫苗到破伤风针,注射在现代医学中是不可或缺的。But do they always have to makeyou say Ouch?但是它们是否就一定会让你尖叫呢?Eh,no?嗯,不会吗?No,indeed.If new microneedle technology is successful, we may soon have needles that inject medicine without your even knowing it.真的不会!如果新的显微针技术成功了的话,我们将很快享受甚至你都不能意识到的药物注射。How does this work, you ask?你快问它是如何办到的?How does it work?如何办到的?You feel things because of the nerves that are embedded in your skin.你有感觉是因为你皮肤里镶嵌的有神经。However, the entiresurface of your skin is not covered.然而,它却没有完全覆盖你的皮肤。From a microscopic viewpoint, there is plenty of spacebetween nerves where a super-tiny needle wouldn’t be felt.在显微镜下可以看到,神经之间有很多空间,而在这里人们便感受不到微型针。No way!不可能!Way! Researcher Mark Prausnitz and his coworkers at the Georgia Institute of Technology inAtlanta have aly built micro-injection devices.可能!亚特兰大乔治亚理工学院的研究人员Mark Prausnitz和他的同伴们已经研制出了微型注射器具。Imagine a platform the size of your thumbnail,made of silicon, metal or glass.试想它就如拇指指甲盖大小,材料是硅、金属或是玻璃。The surface is covered with a thousand needles, each no bigger than aperiod at the end of a typewritten sentence.表面被一千个微型针所覆盖,每一个都还没一个句子中的句号那么大。When this chip is placed on your skin its like rolling in a briar patch-you are pierced again andagain.当这个芯片被植入到你的皮肤就仿佛是卷入到了荆棘区一样,它会一次又一次的刺你。But so small are the briars, you feel nothing.但它是如此的小,以至于你什么都感觉不到。Because they cause no discomfort,microneedles may soon allow doctors to administer controlled amounts of medication over longperiods of time.因为它们不会带来不适感。微型针很快就能让医生在很长时间内掌管在量上有控制的药物治疗。That would be a big step toward the precision medicine of tomorrow–and awayfrom the big Ouch of yesterday.这对于告别以前的疼痛时代、对于将来药物治疗的精准性来说都是迈出了一大步。 201405/299331。