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芜湖第二人民医院治疗龟头炎多少钱宣州市中医院治疗生殖感染价格宣城泾县治疗性功能障碍多少钱 Science and technology科学技术Palaeontology古生物学Remember the tooth齿状物所记A link is made in an ancient ecosystem古生态系统的一环WHO ate whom in the food chains of the past is rarely clear. 过去的食物链中谁吃谁的问题很少能明确下来。尽管哪些物种是捕食者,Though it is obvious which species were predators and which prey,而哪些物种又是被掠食者显而易见,the subtle specialisations of feeding habit that allow many types of carnivore to co-exist are rarely preserved in the fossil record.但是让多种类型的肉食性动物共存的摄食习性的微妙法门却很少在化石记录中保存下来。Rarely, but not never.很少,不等于永远都没有。That is why the recent discovery of a Jurassic ammonite with a sharks tooth embedded in its shell has excited palaeontologists.这正是最近发现的一枚外壳中嵌有鲨鱼齿状物的侏罗纪鹦鹉螺化石令古生物学家兴奋的原因所在。The ammonite in question, Orthaspidoceras, a species that thrived 155m years ago,在1.55亿年前古鹦鹉螺是非常繁盛的物种,was part of the collection of an amateur who did not realise the significance of what he had found.讨论中的这枚鹦鹉螺化石是一个业余收藏家的收藏部分,这位收藏家没有意识到它的重大意义。Romain Vullo of the University of Rennes,然而,雷恩大学的罗曼?武洛意识到了,however, did—and he has brought the discovery to the attention of the scientific world in the pages of Naturwissenschaften.而且他已经借《自然科学》杂志成功地让这个发现受到科学界的注意。Ammonites were both predators and prey.古鹦鹉螺既是捕食者又是被掠食者。They occupied a position in the Mesozoic oceans similar to that of modern squid.他们在中生代海洋中占有一席之地,类似于现代的鱿鱼。Like squid, they were swimming tentacled molluscs—a group called the cephalopods.它们象鱿鱼一样是游动的触手软体动物,这类软体动物被称为头足类动物。Unlike squid, though, they had protective shells.不过,它们不象鱿鱼,它们有起保护作用的壳。These shells were divided internally into gas-filled chambers.这些壳的内部划分成许多充气室。The result had neutral buoyancy, allowing the animal to move by jet propulsion.结果形成中和浮力,使动物能够借助喷气推进移动。Modern pearly nautiluses, whose relationship to ammonites is much debated, have a similar arrangement.现代的珍珠鹦鹉螺与古鹦鹉螺的关系备受争议,但它也有类似的结构安排。What ammonites—or, at least, some of them—ate became clear earlier this year when an X-ray showed a small crustacean in the jaws of a species called Baculites.古鹦鹉螺以什么为食在今年早些时候终于搞清楚了,X光显示了一个被称为Baculites物种的下颌,明是小甲壳类动物。But what ate ammonites has never been shown in such an unambiguous manner.但是,人们还从来没有以这样一种毫不含糊的方式明什么动物以古鹦鹉螺为食。Some ammonite fossils have tooth marks that look as though they were made by huge reptilian predators called mosasaurs.有些鹦鹉螺化石上的齿痕看起来好像是由巨大的爬虫类捕食者沧龙留下的。Some appear to have been attacked by the beaks of other cephalopods.有些看来像是其它头足类动物的嘴袭击过的痕迹。And some seem to have been bitten by sharks.有些似乎是被鲨鱼咬伤的。On top of that, coprolites, as palaeontologists politely describe fossil faeces, have turned up with ammonite shells in them.除此之外,被古生物学家委婉地形容成粪化石的粪便化石中也找到了古鹦鹉螺的壳。Based on comparisons with modern evacua, these are probably from sharks.根据与现代的排泄物相比较,这些化石可能都来自鲨鱼。But which sharks?但是是哪种鲨鱼呢?Dr Vullos ammonite nails one culprit.武洛士的鹦鹉螺化石锁定了一个罪魁祸首。The tooth belongs to a species called Planohybodus.这颗齿状物属于一个被称作Planohybodus的物种。And that is a surprise.这是一个惊喜。Those modern sharks that eat shelled animals have robust teeth for crunching through hard exteriors.以有壳动物为食的那些现代鲨鱼都长着坚固耐用的牙齿,以便咬碎食物坚硬的外壳。The teeth of Planohybodus, in contrast, were slender and pointed—the sort usually associated with grasping and tearing at flesh.相反,Planohybodus的牙齿细长而尖锐,就是通常让人联想到抓住并撕咬肉类的那种。In a modern predator, that would indicate the habit of eating fish.这可能意味着现代肉食动物有吃鱼的习惯。That a shark with teeth like this would try to make a meal of an ammonite is, at first sight, odd.长有这种牙齿的鲨鱼想吃掉古鹦鹉螺,乍一看太奇怪了。But second thoughts provide a possible explanation.但再三考虑就会想到一个可能的解释。Ammonites manoeuvrability would have depended crucially on their buoyancy control.古鹦鹉螺的灵活性关键取决于其浮力控制。Even a small puncture to the shell, which a pointed tooth would be well able to deliver,即使在其外壳上有一个小小的穿刺,这点尖尖的牙齿驾轻就熟,would let the water in and cause that control to vanish.也会让水渗入,造成浮力控制的消失。Since ammonites could not withdraw entirely into their shells for self-defence,由于古鹦鹉螺不能完全缩回壳内自卫,那么就剩一个问题了,it would then just be a question of dragging the creature out of its chamber in order to eat it.即为了吃掉它而把这种动物从壳腔内拽出来。And for that, sharp, pointed teeth are ideal.对于这点,锐利的尖尖牙齿就十分理想了。 点击此处下载本期经济学人讲解PDF与音频字幕 /201304/233642BEFORE the European Union summit on January 30th, Italyrsquo;s new prime minister, Mario Monti, will have visited the German chancellor, Angela Merkel, the French president, Nicolas Sarkozy, and the British prime minister, David Cameron, whom he saw on January 18th. Herman Van Rompuy, president of the European Council, has been to see him in Rome. And the French, German and Italian leaders plan a pre-meeting just before the summit.欧盟峰会将于1月30日召开,在此前夕,意大利新总理马里奥bull;蒙蒂将访问德国总理安格拉bull;默克尔和法国总统尼古拉bull;萨科齐。此前,他还于1月18日访问了英国首相戴维bull;卡梅隆。欧盟理事会常任主席赫尔曼bull;范龙佩也将在罗马与其会面。此外,法、德、意三国领导人还计划在峰会召开前举行一次预会。It is a far cry from most of the second half of last year, when Europersquo;s leaders did as much as they could to avoid being caught in a photograph with Mr Montirsquo;s scandal-tainted predecessor, Silvio Berlusconi. Italy, it seems fair to say, is back at the top table. And that could have far-reaching effects on the euro crisis. For, as he is making increasingly plain, Mr Montirsquo;s ideas on how to resolve it are significantly at odds with those of the Germans who have until now been doing most of the ordering;and choosing pretty thin gruel.这可真与去年下半年的情况大不相同,那时,欧洲各国领导人竭力避免与丑闻缠身的西尔维奥bull;贝卢斯科尼(蒙蒂的前任)同台亮相。而现在,似乎是时候说,意大利又重回贵宾席了。这可能对欧元危机产生深远的影响,因为蒙蒂正愈发清晰地表明在如何解决危机的问题上他与那些德国人的想法大不相同;;到目前为止,德国主要是作为发号施令者(此前德国一直认为只有欧元区各国统一标准、严守财政纪律,才能克欧元区管理存在的结构性缺陷;;译注),却没有给出什么有效的解决措施。;Adherence to fiscal discipline is a necessary condition for growth,; he told an audience at the London Stock Exchange on January 18th. ;It is not however a sufficient condition.; His message to Mrs Merkel and Mr Sarkozy is that the EU must move from reliance only on austerity towards some growth-stimulating measures. This was a view repeated by Standard amp; Poorrsquo;s, the rating agency that downgraded nine euro-zone countries, including Italy, on January 13th. Unlike his colleague from France, also downgraded, and the European Commission, Mr Monti did not criticise Samp;P: indeed, he shared much of its analysis.1月18日,蒙蒂在伦敦券交易所对一名在场观众说道:;遵守财政纪律是保经济增长的必要条件,然而,只有这一个条件是不够的。;他将向默克尔和萨科齐表示,欧盟不能再仅仅依赖于紧缩方案,而应采取一些刺激增长的措施。而这正是标准普尔反复提到的观点一致;;标普是一家评级机构,它在1月13日下调了包括意大利在内的9个欧元区国家的信用等级。与欧盟委员会以及同样被降级的法国同僚不同,蒙蒂并未指责标普:事实上,他认同很多标普所做的分析。Mr Monti, who served as the EUrsquo;s commissioner for the single market and then competition between 1995 and 2004, is a rare creature: an Italian economic liberal. He is not a proponent of harrying Berlin to reflate to boost domestic consumption. But he would like to see the Germans do more to liberalise their own services, to bolster the EUrsquo;s single market (indeed, he wrote a report for the commission in May 2010 advocating further liberalisation).蒙蒂在1995年到2004年间曾先后担任欧盟内部市场专员和竞争委员会专员,他是一名罕见的意大利经济自由主义者。他并不提倡迫使德国政府再度采用通货膨胀的方式来拉动内需,却想要看到德国努力使其市场自由化,以促进欧盟统一市场的发展。(其实,他在2010年5月就写了一份报告给欧盟委员会来提倡进一步的自由化)。In London this week Mr Monti pledged to back a British effort to complete the single market, and thus to improve competitiveness throughout the EU. Although he believes it is unrealistic to expect Mr Cameron to go back on his refusal in December to sign up to the proposed fiscal compact between EU members, he is keen to involve the British as much as possible.本周蒙蒂在伦敦承诺将持英国为构建完整的统一市场所做的努力,从而全面提高欧盟的竞争力。卡梅隆曾在12月份拒绝签署欧盟成员国之间的财政条约。虽然蒙蒂觉得,要想让卡梅隆改变主意,恐怕不太现实,但他热切期望英国能够尽可能多地参与进来。Speaking before his visit to London, in his office in Palazzo Chigi in Rome, Mr Monti says: ;The more the UK feels distanced from European construction, the less others are able to benefit from the full influence of the many good things that the UK can help us all to achieve, and therefore there are many areas where I think it would be beneficial to have the UK fully at the table.;出访伦敦之前,在坐落于罗马基奇宫的总理办公室中,蒙蒂说道:;英国可以帮助我们各国达成许多具有全面影响的积极措施,而英国越是被排除在欧洲市场建设之外,其他国家能够从中得到的利益也就越少,因此,我认为英国的全面参与会使我们在诸多领域获益。;201201/169393宁国市海螺总医院治疗早泄多少钱

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宣城早泄哪里治疗 This was the catalog of Einstein Effect measuring equipment.这是爱因斯坦效果测量设备的目录。First eclipse point is the very very very western most part of Australia.第一个日食观测点是在大多数澳大利亚的一部分,非常非常非常西面的地点。A place called 90 Mile Beach.一个叫做90英里海滩的地方。But this time Campbell is not the only pursuing this goal.但这一次坎贝尔不是唯一追逐这一目标的人。Seven, seven expeditions went to Australia.有7,7探险队奔赴澳大利亚。The British sent an expedition.英国派了一探险队。Freundlich led an expedition.弗雷德里奇率领一探险队。It was the first time he had a chance since Russia.这是他自俄罗斯以来第一次有机会。John Evershed, a British astronomer, was even able to come from India.英国天文学家约翰·艾佛甚至能够自印度而来。The Canadian sent an expedition.加拿大派出一探险队。And two Australian expeditions went. Serious competition to Campbell.两澳大利亚探险队也前往。而这是坎贝尔重要的竞争对手。The British and Freundlich got clouded out.英国和弗雷德里奇感到阴云密布。One of the Australians couldnt get any data.澳大利亚的一探险队无法得到任何数据。Their equipment was lousy.他们的设备很糟糕。注:听力文本来源于普特201206/185129宣城哪里检查男科宣城哪里治疗包皮龟头炎最好



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