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2019年09月23日 06:35:20

Europe;Europes banks; The fear factor; Preventing a big European bank run;欧洲;欧洲的们;忧虑因素;阻止一场欧洲大规模挤兑;In continental capitals and bank boardrooms there is a common fear. It is that the slow jog of deposits leaving banks in Greece and, more recently, Spain, may turn into a full-blown run that quickly sps from bank to bank, and then from country to country. There have aly been some warning signs, such as a sudden acceleration of deposit outflows from Greek banks in May.在欧洲大陆各国首府和的董事会议室里弥漫着一种担忧。 希腊各大的存款量正在平缓流失, 新近西班牙各也陷入同样境况, 这很有可能会转变成一场全面的挤兑风暴, 并迅速在乃至国家之间传播。 对此已早有征兆, 五月份希腊各的存款外流骤然加速就是例。A fierce debate is now taking place as to the best way to avert a run that, if it started, might be difficult to contain and could lead to massive capital flight from the euro zones peripheral countries, which have 1.8 trillion Euro(2.2 trillion Dollar) in household deposits (see chart). Increasing numbers of people think the answer is greater financial integration. On May 30th the European Commission said there ought to be “full economic and monetary union, including a banking union; integrated financial supervision and a single deposit guarantee scheme”.目前, 关于如何最为有效地防止一场全面风暴正引起一场激烈争论。 因为挤兑一旦开始蔓延, 可能难以遏制, 而且可能导致欧元区边缘国家出现大量资本流失, 而这些国家家庭存款拥有量达1.8万亿欧元(即2.2万亿美元)。(如图所示)。 越来越多的人认为应该加强欧元区金融一体化。 5月30日, 欧盟委员会指出应建立;全面的经济与货币联盟, 包括业的联盟; 以及完整统一的金融监督和单一存款保障计划;。The first step is to shore up confidence in the regions banks by making sure they have enough capital to withstand a crisis. It is far cheaper to recapitalise banks, after all, than to stand behind all of their deposits. Yet such efforts have been bungled time and again. Europe has twice over the past two years tried to reassure depositors and investors that its banks are sound by subjecting them to “stress tests” that were supposed to mimic an economic downturn. In each case the tests were soon followed by revelations of deep capital holes in some banks (newly nationalised Bankia among them). Since some national regulators have lost the confidence of markets, they are having to bring in outsiders to assess how much capital their banks need.第一步, 要通过确保区域内各有足够的资金能够抵御一次经济危机, 以此增强的信心. 毕竟, 调整资本结构相比保障各的存款量, 所需代价要小的多。 然而这样的努力却一再以失败告终。 在过去两年中, 欧洲曾两次尝试让各在一场摹拟的经济危机中接受;压力测试;, 明这些都运作良好安全可靠, 试图以此恢复储户和投资者们的信心。 但紧接着这两次压力测试之后均有消息曝出某些存在严重的资金缺口(其中包括一些新近被收归国有的)。 因为一些国家监管机构已经失去市场的信任, 他们正被迫请一些机构外的人士来参与评估这些所需资金量。Actually raising the capital is the next big problem for countries such as Spain or Italy, which are aly struggling to convince markets that their public debt is sustainable. Ideally it should come from the European Stability Mechanism (ESM), Europes new bail-out fund, as a direct capital injection into banks rather than as loans to governments, which then use the money to recapitalise their ailing lenders.实际上, 募集资金是西班牙, 意大利等国家面临的下一个大问题, 他们已经在费尽心思希望说市场相信其国债的可持续性。 理想的办法是, 他们所需资金能由欧洲稳定机制(ESM)提供, 作为欧洲新的紧急财政援助基金给直接注资而非贷款给政府部门, 然后再利用这些资金对其陷入困境的进行资本结构调整。Injecting capital is politically difficult. Core countries such as Germany fret they will lose a lever of influence over government policies in peripheral countries by handing over equity. They also stand a greater chance of losing money if the ESM takes on the risk of bank investing, not least because they know even less about the balance-sheets of individual lenders than those of national governments. Peripheral countries are less than keen on handing ownership of important banks to bureaucrats in Brussels. And unless the capital is accompanied by supervisory reforms, local regulators may encourage banks to lend more freely at home since the risk of loss will have been exported.直接注资从政治上讲很难实施。 德国等核心国家担心一旦转付资金他们就会失去其在边缘国家政府政策制定方面的影响力。 如果ESM冒险给注资, 他们面临经济损失的风险会更大, 相当重要的原因是他们本来对各资产负债表的了解比对各政府的资产负债表的了解还要模糊。 各边缘国家也不想将他们重要的所有权交给布鲁塞尔的官僚们。 并且注资同时如不进行监督机制改革, 当地监管机构可能会鼓励更多地为本国个人或机构提供贷款, 因为损失的风险会被输出。Recapitalising banks would not put the catch on every trigger for a run, however. The worry among depositors is not just that their bank will go bust, it is also that their deposits in euros may overnight turn into a less valuable currency. So savers in the periphery would need some additional reassurance that their money is safe.尽管如此, 的资本结构调整不会触发挤兑危机. 储户们担心他们的存款会破产, 同时也害怕他们以欧元为计算单位的存款会在一夜之间贬值。 因此, 要让边缘国家的储户相信他们的存款是安全的还需要一些其他的安抚措施。 The job of providing this extra comfort usually falls to national deposit-insurance funds, ideally ones that are prefunded with assets worth about 1.5% of insured deposits, as is the case in America and Europe. If a medium-sized bank goes bust, prefunded schemes can usually pay depositors immediately; European countries insure qualifying deposits up to 100,000 Euro. For big banks, or for systemic crises, funds are usually backed by their governments.这项额外的安抚工作通常是由国家存保机构来完成的. 按照美国和欧洲的当前情况, 最好是预先拨款资金额等同于承保存款额的1.5%. 如果一家中等规模的倒闭, 预先拨款计划可以立即启动, 对储户进行偿付, 欧洲国家对符合投保要求的存款承保上限为10万欧元。 至于大破产或涉及整个金融系统的危机, 则由政府出资解决。Such schemes are fine in normal times, but do not do much to reassure people that their deposits wont be repaid in a different currency (or that their money will be safe if their own government cannot stand behind the scheme). That has prompted calls for a European insurance fund which would guarantee repayment in euros. The idea is appealing, but the politics and logistics of a credible guarantee are daunting.这样的计划在一般情况下是没有问题, 但要使人们相信他们的存款不会通过另一种货币来偿还则作用不大.(如果他们的政府都无法撑起这样的计划, 他们也就很难相信他们的存款是安全的). 这就使得必须有一种欧洲保险基金能够担保在存款偿付时使用欧元。 这种想法是十分吸引人的, 但实施一项可信的担保计划涉及的政治事务和组织工作却令人望而生畏。Household and corporate deposits across the euro area total some 7.6 trillion Euro. Assuming you wanted to limit the insurance to household deposits only, the figure is still 5.9 trillion Euro. Not all of this would be covered by a guarantee. A European Commission study in 2010 reckoned that 72% of deposits (and 95% of deposit accounts) fall under the 100,000 Euro limit. Whats more, a European fund would not have to be big enough to deal with simultaneous deposit runs across all of Europe but only with ones in the periphery, since money would presumably flow to banks in core countries such as Germany. So the fund would have to be big enough to cover only some 1.3 trillion Euro in insured deposits in the periphery.整个欧元区的家庭与企业存款总和达7.6万亿欧元。 假使你只为家庭存款提供担保, 承保金额也达5.9万亿。 这些存款不会都得到担保。 欧盟委员会2010年的一项研究推测有72%的存款(95%的储蓄账户)在10万欧元承保限额的范围之内。 更重要的是, 欧盟基金无需庞大到足以应付欧洲各国同时发生存款流失危机,仅需足够应付边缘国家发生的此类情况即可。 因为存款应该是流向德国等核心国家的。 如此一来, 欧盟基金就只需足够担保边缘国家大约1.3万亿存款。The question then is how much of that amount a prefunded scheme would have to set aside. Economists at Citigroup reckon that a fund ought to start with a baseline of 2% of insured deposits, and then top up that amount with an additional premium to reflect the risk that peripheral countries may leave the euro and that their currencies would then depreciate. Assuming a less-than-10% chance of all the peripheral countries leaving, and that when they did their currencies would fall by 30%, a prefunded scheme would need 154 billion Euro-198 billion. Such a fund should ordinarily be financed by a small insurance premium on deposits, but since the money is needed to restore confidence now, it would have to be backed by the ESM.问题在于这项预先拨款计划需要拨出多少资金。 花旗经济学家认为这笔资金必须以承保存款总额的2%为下限, 再在此基础上加上一个风险溢价, 用以反映边缘国家可能退出欧元区及其货币随之贬值的风险。假定所有边缘国家都退出欧元区的可能性低于10%, 且他们一旦退出, 他们的货币会贬值30%, 那么这项预先拨款计划将需要1540-1980亿资金。 这样一笔资金通常是由小型存款保险费来付, 但现在正需要钱用来重塑储户信心, 导致这笔资金只能由ESM来提供。Again, none of this is easy to achieve. Banks and voters in core countries (let alone Britain, whose position in a more integrated European banking system is very muddy) would be reluctant to insure peripheral deposits. Without beefed-up European supervision, it could lead to banks taking too many risks. Critics say that even a prefunded scheme would soon be depleted were a run to take hold. But a flawed scheme would be better than nothing.不过, 这一切完成起来都是困难重重. 各核心国家的和当权者们(英国更不用提, 在日益完整统一的欧洲体系中, 其地位十分扑塑迷离)都不愿意为边缘国家的存款提供保障.不增强欧盟的监管职能, 可能会导致承担太多风险。 批评家们称形势一旦恶化, 即便是预先拨款计划也会被迅速耗尽。 但是一项有缺陷的计划总要好过什么都不做。 /201303/232031厦门薇格衡力瘦脸针果酸换肤果酸去痘坑多少钱Long Live Us人类万岁About a century ago, the average life-span for Americans was about 50 years. Today, the typical American lives for around seventy-eight years.约一个世纪以前,美国的人均寿命是50岁左右。如今,美国一般都能活到78岁左右。According to a German aging study, the maximum life span in industrialized countries has increased by two years every decade since the mid 19th century. What accounts for such increased longevity?德国一项关于寿命的研究指出,19世纪中叶以来工业化国家人口的最高寿命增长迅速——每十年人们的最高寿命就会增长两岁。是什么让人们的寿命增长的如此之快呢?Between 1900 and 1950, inventions such as refrigeration and sewage treatment meant that young people were able to survive longer. Moreover, medical breakthroughs helped contain diseases such as polio, which killed many children. These advances helped increase the average life span.1900年至1950年期间,制冷技术及污水处理的发明便意味着年轻的一代能活得更久。再者,医疗水平的重大突破对一些疾病起到了很好的控制作用,例如夺去许多儿童生命的小儿麻痹症。社会的这些进步都有助于提高人类的平均年龄。Medical discoveries after World War II tended to benefit older people. Treatments for heart disease, for example, have allowed the elderly to live longer on average. So does this mean that future medical breakthroughs will result in even longer average life spans, or have we reached our limit? Scientists disagree.二战后的科学研究都倾向于“造福”老年群体。就拿对心脏病的治疗来说,就大大提高了老年人的平均寿命。那我们是不是就可以由此推出——日后的医学突破将会使人类的平均寿命再得到延长,或是,人类已经达到了生命的极限?科学家对此持否定看法。Some argue that if science is one day able to eradicate disease and old-age infirmity, there will be virtually no limit on how long humans can live. Some even predict that by the year 2150, the average life span will have increased to around 120 years.有人认为,如果科学能够消除一切疾病以及年老体衰,那么人类的寿命就没有了限度。更有甚者,有人预测到2150年,人类的平均寿命将会达到惊人的120岁。Other life-expectancy researchers find that scenario highly unlikely. Our bodies cells can keep reproducing for only so long before they peter out. Only when science finds a way to keep our cells dividing longer will we see another significant leap in life expectancy.其他的寿命研究人员认为这样的假设是不可能的。人体细胞只能在细胞数量逐渐减少前不断进行复制。除非科学家们找到方法延长细胞分裂时间,人类的平均寿命才可能再有一次突飞猛进。Still, with plenty of exercise and a healthy diet, those so inclined can always hope that theyll live long enough to break the record held by Jeanne Louise Calment of France, who lived to be 122.当然,那些赞成此种观点的人也可以怀抱这样的一份希望——坚持锻炼,养成健康的饮食习惯,打破法国Jeanne Louise Calment老人122岁的长寿记录。 /201211/211588厦门薇格医院打美白针多少钱Beginning in the summer of , we alleged that executives at the highest levels of the companies included in today’s lawsuits, concerned the e-book sellers had reduced prices, worked together to eliminate competition among stores selling e-books, ultimately increasing prices for consumers. Now as a result of this alleged conspiracy, we believe that consumers paid millions of dollars more for some of the most popular titles.年夏季初,我们起诉了苹果及多家出版公司的最高主管,他们涉嫌操纵电子书售价,合作共谋提升电子书市场的竞争力,最终导致消费者付更高的电子书价格。我们相信,他们这次的阴谋导致了消费者在最畅销的电子书上多付了几百万美元。We alleged that the CEOs of the publishers bemoan the wretched 9.99 price point. One executive said that the goal is ;Lets to compete with Amazon, as to force it to accept a higher level than 9.99, and yet another, we’ve always known that unless other publishers follow us, there’s no chance of success in getting Amazon to change its pricing practices. Our complaint also es Apple’s then CEO Steve Jobs as saying “The customer pays a little more, but that’s what you want.”and he’s referring to the publishers. That’s what you want anyway. As you can see, we alleged that these executives knew full well what they were doing, that is ;Taking steps together to make sure the prices consumer paid for e-books were higher;.我们控告出版公司的首席执行官们不以9.99美元的价格点为准。一位执行官说,他们的目标是“赶上亚马逊,强迫它接受高于9.99美元的价格”。此外,我们一直认为,除非其他的出版商跟随我们,否则没有机会让亚马逊改变标价。我们的顾客投诉时引用了苹果首席执行官史蒂芬·乔布斯的语录“让消费者再多花点钱,那就是你想要的”。在这里他指的是出版商。总之,这是你们想要的。正如我们看到的,执行官们清楚他们在做什么,即“一起采取措施,确保消费者为电子书付更多的钱。”The Department of Justice is committed to ensuring that e-books are affordable as is possible. As part of this commitment, the Department has reached a settlement with 3 of the nation’s largest book publishers and well continue to litigate against Apple into additional leading publishers for conspiring to increase the prices that consumers pay for e-books.美国司法部承诺会让消费者以合理的价格购买电子书。作为承诺的一部分,司法部与美国最大的3家图书出版公司达成一致协定,我们将持续就与出版公司共谋蓄意推高消费者电子书价格,向苹果公司提出诉讼。201206/186011Imagine a kitchen without pots, pans or even recipes. Its a concept that one of the worlds largestappliancemakers envisions for the future. The heart of the whole unit is an all-in-one kitchen surface, kitchen table and bar. The changeable work area with the cooker, table and pots adjusts its shape when directed by the user. To use it, the cook places ingredients on the surface which analyses them to come up with recipe suggestions. Then the user marks with the hand size of the area. The depth is adjusted by pressing the malleable surface. Once the surface fits the requirements, the user sets the time and temperature with the swipe of the hand. The table can also determine whether the ingredients are fresh.想象一下厨房如果没有锅碗瓢盆会是什么样子。这就是世界上最大家电制造商眼中的未来厨房。整套厨房设施的核心就在于全能料理台。用户使用时可直接调节工作区大小。为了应用方便,放置食材的台面可以显示菜单。然后,用户用手选定工作区,工作区深度由可延展的台面决定。当台面符合烹饪要求时,用户手动设定时间和温度。料理台甚至可以自动判断食材是否新鲜。We want to create a concept that allows for a morph-living, which means you can have a living space that can either be your living room, your social zone, your kitchen, your bedroom, whatever that sort of adapted itself to how you live your life and what different situations you are in.我们是想创造一种灵活的生活方式,也就是说营造一种生活空间,包括客厅,会客室,厨房,卧室。这些空间都会因为你的生活情况而改变。Some of the materials for the unit aly exists, such as the malleable ferrofluid, a material usually made up of about 5% magnetic solids, 10% flatant and 85% carrier.这类台面的材料已经诞生了,比如可塑性铁磁流体,这是一种由5%磁性固体,10%flatant材料和85%的架组成。One of the biggest challenges is of course that you are skipping a number of product interations because you are looking so far into space all the time. So its a number of product generations that you dont actually do so you are saying that, well done, take it quantumly and look at how are people gonna socialize. To do that, you are gonna have to release yourself from preconceived ideas what you can or what you cant in your own industry.很明显,现代人生活的最大挑战生活空间太小,我们总是忙于寻找足够的空间而忽视了各项事物相互之间的联系。所以,有很多产品你并没有用过,好了,从宏观的角度去看待人类的社会性。要实现这一点,我们公司首先要做到的就是合理地预见自己能和不能做到的事情。The company says for now, the concept is meant totriggerdiscussion, feed-back and ideas from designers and scientists. The company says it is doing a lot of trend in consumer research into how people would live and socialize in the future. According to research by the ed Nations, 74% of the worlds increasing population will be living in cities by 2050, making it necessary to rethink how space and energy is used and the environmental impact.这家公司表示,现在这一理念引发了设计师和科学家们的一系列想法和反馈。公司针对未来人类理想生存和生活状态。根据对美国人的调查,到2050为止,世界上74%的人口增长将会在城市,因此重新考虑空间和能源消耗和环境保护是十分重要的。Natalie Armstrong for Reuters.com.路透社消息,Natalie Armstrong报道。appliance家用电器triggervt. 引发 n.扳机The earthquake may trigger landslides or similar local surficial movements.地震会引起滑坡或类似的局部地表运动。He pulled the trigger and the bottle was shot to pieces.他扣动扳机,瓶子当即被打得粉碎。注:本篇文章英文来自普特论坛,译文属原创,,。201206/186653厦门薇格整形美容医院丰唇

厦门思明Vmax薇格医院电话号码是多少龙海市祛除胎记要多少钱;Of course, I cant show you a picture of the galaxy on our screen. We cant fly above the galaxy and take a picture of it, and show you. Were stuck in the disc of the galaxy, but we can still image it from the ground, in fact, this image is a picture of our galaxy, the Milky Way, taken from Earth.;;当然,我不能在我们的屏幕上向你展示一幅巨大的星系。我们不能飞往整个系并拍下它展现给你。我们被困在之中,但是我们仍然可以从地面拍摄照片,事实上,这张照片是我们的星系,系,这是从地球上拍摄的照片。;This is one of the most detailed images of our galaxy ever created. Its made from 800 million pixels contained in over 1,000 individual photographs taken from the darkest places on earth.这是一张非常详细的我们的星系曾经创造的照片。它是用8亿像素包含超过1000张来自地球最黑暗的地方的独立照片。The photos have been painstakingly stitched together to create this breathtaking vista. But as impressive as it is, its only part of the picture.这些照片被精心制作在一起来展现这惊人的景象。但令人印象深刻的是,这只是照片的一部分而已。;Its something like a pizza and if you were in the pizza, if you were pepperoni, your view would not be a very clear one of what the whole story was. In the same way, we dont see the whole reach of the Milky Way.;;这有点像一张比萨饼,若你身处于比萨饼中,如果你是辣味香肠、你就不能窥探到全貌。如出一辙的是,我们并没有看到整个系。What astronomers really need is a birds eye view.天文学家们真正需要的是鸟瞰风景的慧眼。注:听力文本来源于普特201203/173124The Green Door绿色的门Don: Heres a simple demonstration you can do with cool implications. Find a large object that is brightly colored—lets make it a green door.告诉你一个很简单的论:通过它你可以得出很酷的。找到一个大的颜色鲜艳的物件——将其视作一扇绿色的门。Stand with that door to your side but dont look directly at it; you want it to be in your peripheral vision. Now, without shifting your gaze, examine the door in the edge of your field of vision. What color is it? Answer? Its still green.靠着那扇门站定,但是不要直视它,只是把它纳入你的周边视野即可。现在,不改变凝视的方向,从你视野的最边缘仔细看看那扇门。它是什么颜色的?是什么?那扇门依然是绿色的。Yael: Its still green? What kind of experiment is that? I thought you are going to say something happens to the color.还是绿色?这是个什么实验啊?我猜你接下来应该会讲讲,那扇门的颜色究竟发生了什么神奇的事情。D: Thats exact right! The color stays green, which means something has happened—because nothing in your peripheral vision should have any color at all.当然!门保持绿色就意味着发生了什么改变——因为在周边视野范围内事没有什么颜色的。Y: Nothing in your peripheral vision should have any color? Why not?周边视野范围内是没有颜色?为什么?D: Because color is what we perceive when light of a particular frequency meets cones–special cells in your retina. But the light being reflected off the door is only landing on the outside edge of your retina. And there are almost no cones on the edges. Everything we see roughly seventy-five degrees away from the point were fixed on should be black and white.因为,当特定波长的光线作用于视锥细胞(视网膜中的一种特殊的细胞)时我们所接收到的便是颜色。但是,从门上发射出来的光线仅能到达视网膜的外缘,在视网膜的外缘几乎没有视锥细胞。从我们所凝视的方向斜75度角所看到的所有东西都只能是黑白的。Y: Thats fascinating! But why is the door still green?太神奇了!可为什么门还是绿色的呢?D: Presumably the door remains green because vision isnt a simple matter of retinal cells. All the data your eyes send is interpreted by the brain. Your brain knows that the door is green, so it supplies information that isnt really there to keep the image stable.门一直保持绿色大概是因为我们的视觉并不仅仅是视网膜细胞所能控制的吧。由眼睛传送的所有信息都是经过大脑编译的。大脑所给出的信息是:门是绿色的。因而,大脑传送出了并未遵循图像的信息。This is just one of the many ways your brain saves time and energy by making reasonably safe assumptions about the world around you.为节省时间与精力,大脑对你周围的世界作出合理、安全的假设——而这仅仅是众多省时省力的方法之一。 /201211/209354福建省厦门薇格整形医院祛疤痕多少钱Science and Technology Animal behaviour Drip-feeding科技 动物行为 滴定进食Ecology raids the techniques of chemistry生态学里应用上了化学技术。BIOLOGISTS are sometimes accused of physics envy—and there is truth in this accusation. The essential fuzziness of biological systems can never be captured by the precise, mathematically based experiments of something like the Large Hadron Collider. Between physics and biology on the spectrum of fuzziness, though, lies chemistry. And a group of researchers led by Carolyn Nersesian of the University of Sydney has just borrowed one of chemistrys most elegant techniques, titration, to answer a pressing ecological question: how do animals choose where to feed?生物学家们常常被认为非常嫉妒研究物理学的人(事实上确实如此)。他们永远不可能通过像大型强子加速碰撞那样精确、量化的实验来揭示生物学里的一些关键性的奥秘。但是在这种奥秘的;两极;——物理学和生物学之间还有化学。最近由悉尼大学的卡洛琳·涅尔谢相带领的一组研究人员借用化学里一种非常精妙的技术——滴定法来解决一个迫待回答的问题:动物们如何选择觅食场所。Titration, to remind those who dozed through their chemistry lessons, is a way of working out the concentration of a substance in a solution. A reagent of known concentration is dripped (or titrated, to use the term of art) into the unknown solution in the presence of an appropriate indicator molecule (for example litmus, in the case of a reaction between an acid and an alkali). When the tipping point comes, and all of the unknown reagent has reacted, the solution changes colour. The unknown concentration can then be calculated from the amount of known reagent used.滴定法(为了给那些在化学课上打过瞌睡的同学们提个醒)是一种计算溶质在溶液中的浓度的方法。在某种特定的指示分子的参与下(例如,酸溶液和碱溶液的反应中我们使用石蕊指示剂),将一种已知浓度的溶液滴到(专业术语叫滴定)未知溶液中。当滴定终点到来时,所有的未知溶液全都完成了化学反应,溶液的颜色就会发生变化。然后未知溶液的浓度就可以通过被消耗掉的已知溶液的体积计算出来。In Dr Nersesians titration the litmus was a species called the brushtail possum. The two reagents were predators and poisons. In the wild, possums feed mainly on eucalyptus trees. Feeding in trees this way also keeps them safe from ground-based predators, such as foxes. They frequently have to shift from tree to tree in search of non-poisonous leaves, though, because a tree that is being browsed starts manufacturing toxins. Dr Nersesian reasoned that there is probably a measurable point at which a plant becomes so toxic that possums prefer to take their chances with the predators on the ground—and she realised this was a perfect opportunity to do an ecological titration.涅尔谢相士的滴定实验中的;石蕊指示剂;是一种叫帚尾袋貂的动物。那两种溶液是;猎食者;和;有毒物;。在野生环境下,袋貂主要以桉树叶为食。生活在树上也能让它们安全地远离地面上的那些猎食者——例如狐狸。但是他们还得经常从一棵树上换到另一棵树上去寻找那些没有毒的叶子。因为一颗树如果被它们吃久了就会自动分泌毒素。涅尔谢相士认为可能当植物中的毒素达到一个量值的时候,袋貂会选择冒着被猎食的风险(途经地面换一棵树觅食),然后她就意识到这是一个应用生态滴定法绝好的机会。As she reports in the Journal of Animal Ecology, she attempted to imitate the distinction between trees and ground by giving eight possums the opportunity to feed in either of two enclosures. In one, cover was created with eucalyptus branches and light levels were kept low, mimicking an arboreal habitat. Here, the food was sometimes spiked with cineole—a poison often found in eucalyptus leaves. In the other enclosure, the food was always untarnished. However, no cover was provided and fox scent, in the form of faeces and urine, was scattered liberally around, mimicking conditions on the ground.她发表在动物生态学报上报告中写道:她通过给8只袋貂两种桉树来选择觅食来模拟树上和地面的区别。一棵桉树上,有特意放置的桉树枝来遮挡,光照强度也很低,模拟出适合树栖动物习性的环境。但是,这种树上的叶子有时含有桉树脑——桉树叶中常见的毒素。另一棵桉树上,叶子总是无毒的,但是,没有树枝的遮挡。而且通过将一些狐狸的;踪迹;,例如狐狸的脸谱尿液随意四散在周围,来模拟地面环境。To start with, when the level of cineole was low, possums preferred the first enclosure. But as the drip of the titration went up, from 0% to 1% to 2% to 5% and ultimately to 10% of the food being cineole, their behaviour changed. It was not quite the sudden shift from litmus red to blue of an acid being neutralised by an alkali, but it was not far off.开始桉树脑的浓度很低,袋貂都喜欢第一棵桉树。但是随着滴定程度的上升,食物中的桉树脑含量从0%到1%到2%到5% 到最终的10%,它们的行为开始出现变化。虽然不是完全像酸溶液完全被碱溶液中和时石蕊试剂突然从红变蓝那样迅速,但是也差不太多。When the food was toxin-free, the possums spent an average of 40 minutes of every hour eating safely under treelike cover and only 20 minutes in the risky, ground-like enclosure, and that scarcely changed for 1% and 2% cineole. The switch began at 5%, and by the time the cineole level had reached 10% the ratio of time the animals spent in the two enclosures had reversed itself—presumably reflecting, though this remains to be tested, the point at which they change trees in the wild.当叶子无毒时,袋貂们每小时用平均40分钟的时间在树枝状的遮蔽物下安全的进食。而在危险的类地面的桉树上只待20分钟,这时的桉树脑含量变化在1%到2%之间。分界点出现在5%,当桉树脑含量达到10%,这些小动物们呆在这两颗桉树上的时间比完全颠倒过来了——这大致上能反映在野外环境下它们换树进食时的毒素量值,当然这还有待验。Though foxes are of recent introduction in Australia (having been brought for sport by British settlers), many marsupial predators, now extinct, were present before the arrival of man in both his Aboriginal and his European forms, so the ecological system of plants, herbivores and carnivores in the eucalyptus forests would probably not have been that different in the evolutionary past. A neat illustration, then, of co-evolution between three different parts of an ecosystem—and of the value, even in biology, of precise measurement.虽然狐狸是很晚才被引进到澳大利亚的(由英国移民出于狩猎运动的目的而带来的),但是在原始人或者欧洲人到来之前还有很多其他的有袋动物的猎食者(现在都灭绝了)。所以桉树林生态系统中的那些植物,素食动物肉食动物,与进化史中较早的生态系统相比,差别可能也没有那么大。这样一来生态系统中的三个不同角色的(植物,素食动物,肉食动物)协同进化的一张清晰的图表呈现出来。在生物学里也能进行精确的量化计算,这种尝试的价值是巨大的。 /201301/221409厦门激光脱毛医院

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