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2019年09月16日 02:44:34来源:医诊疗

  • What a difference a day makes!一天的变化竟然如此之大!Just yesterday, Japans markets were cheering the US debt deal ending up, but today, markets closed down to 1.2%. Why?就在昨天,日本丰田股市还沉浸在处理完美国债务的喜悦中,但是今天股市收盘却降至1.2%。为什么呢?Lingering concerns about the real US economy as well as the value of the US dollar versus the surging Yen.对美国经济现状以及美元对日元贬值的疑虑一直挥之不去。Despite the passage of the house deal, the markets reacted negatively to a manufacturing report, weak dollar is especially hurting corporate Japan, eating into corporate profits, when that money is repatriated back here in Japan.即使不考虑已经通过的外汇买卖,股市仍然很排斥制造业。尤其是在资金遣返回日本时,疲软的美元会危及日本的经济,蚕食企业的收益。We saw the currency issue play out at Toyotas first quarter earnings, Toyota saying that its net income for the months from April to June of this year fell 99.4% year on year.与第一季度的财政收入对比一下,我们就可以看出丰田目前的情况。丰田公司称他们今年从四月到六月这三个月的净收入比去年同期下降了99.4%。Toyota did raise earnings forecast for the full fiscal year though.然而之前丰田却预测今年的财政年收入会增加。Toyota says it is still hurting in the aftermath of the tsunami and the earthquake, but also hurting the company severely is a weak US dollar versus a surging Yen.日本丰田称他们的市场仍然遭受着海啸和地震后的不利影响,同时美元对日元的贬值也严重威胁着丰田公司。An executive after earnings called the currency exchange “too much for manufactures to bear”.丰田一位财政官员称外汇是“制造商难以承受之重”。“I understand that it is a fate to adapt to ever changing exchange rates, but this situation where the Yen has passed 80 yen and it is now at 76 yen, for our exporters, its extremely tough.”“我明白我们必须适应不断浮动的汇率,但是在有些地区美日汇率已经超过了1:80,而现如今达到1:76,对那里的出口商而言,这样的情形是极其严峻的。”He also added that they are having trouble: Toyota that is having trouble keeping up with the currency trend of the US dollar versus the yen.他也补充了亟待解决的难题,即丰田公司很难做到与美日汇率保持同步。So now all eyes are turning to the Bank of Japan who meets on Thursday of this week, Thursday and Friday amid heavy speculation that there could be some intervention on the yen.所以现在所有人都在关注日本的举动,他们将在这个星期三举行会议。会议之后的星期四和星期五将会充斥着各界对是否会出台政策干预日元的猜测。Kyung Lah, CNN, TokyoKyung Lah,美国有线电视新闻网,东京文本来源于普特论坛201205/180512。
  • Science and Technology Materials science Stronger when stricken科技 材料科学 越敲越结实A new material that gets stiffer when it is stressed一种受外力时硬度提高的新材料ONE of the valuable properties of bone is that when it endures repeated stress it responds by becoming denser and stronger.骨头有一种很珍贵的属性,那就是当受到反复的击打时,其质地反而会变得更加紧密,坚硬度变得更高。A living material can do that. A non-living one cannot.只有活性材料具备这种特征,非活性材料则不具备。It has no way of adding the extra matter needed to provide the extra density. But it would help engineers a lot if non-living stuff could at least stiffen in response to stress—and that may now be possible.用添加必要物质来让材料获得更高密度的方法是不可行的,但如果非活性材料起码可以在外力作用下变得坚硬—目前达到这一点是可能的,那么这对工程师们来说有非常大的借鉴意义。Brent Carey, a graduate student at Rice University in Texas, thinks he has found a way to make it happen.布伦特凯利是一名德州莱斯大学的研究生,他认为他已找到了实现这一设想的办法。Mr Carey made his discovery when he was testing the properties of a material made of carbon nanotubes (cylinders of carbon atoms a few billionths of a metre across) and a rubbery polymer called polydimethylsiloxane.凯利在测试一种材料的属性时有所发现,该材料的成分包含碳纳米管(直径为几纳米的碳原子圆柱体)和一种名为聚二甲基硅氧烷的橡胶聚合物。He created this composite by growing a forest of nanotubes using hot hydrocarbon gases and an iron catalyst, and then filling the space between the tubes with the polymer.材料的合成过程是这样:首先,他使高温碳氢混合气体和铁催化剂相互作用产生密集的碳纳米管群,然后再用聚合物充填碳纳米管间的空隙。The surprise came when he discovered how his new material responded to repeated stress.当他注意到新材料受到连续作用力而产生反应时,令他惊讶的现象出现了。He found this did not cause any of the damaging fatigue that would be expected.据他观察,预期中的材料损毁性疲劳并未产生。Indeed, his initial inspection suggested the stuff was actually growing stiffer.实际上,他的初步监测显示材料变得更加坚硬了。Fascinated by this result, he took his finding to his supervisor, Pulickel Ajayan, and they assembled a team to study the new material.这个结果让凯利喜出望外,他马上找到了自己的导师普里克尔阿贾扬,随后他们成立了一个小组,专门研究这种新型材料。They gave the composite a real workout. They compressed it five times a second for a week. That caused its stiffness to increase by 12%.他们给这种合成材料做了次实验:对该材料施加5.5倍的压力,时间持续一周,结果材料硬度提高了12%,Moreover, the effect showed no sign of abating,并且这种状态没有减弱的迹象。which led them to suspect that if it were exposed to more stress it would grow stiffer still.研究小组由此设想,如果对其施以更大的作用力,这种材料的硬度是否会变得更高。Why this happens is still a mystery.产生这种效果的原因还是个谜。Mr Carey and his colleagues report in the American Chemical Societys journal Nano that heating the new material did not eliminate the response.凯利和他的同事们发表在美国化工科学院的期刊杂志《Nano》的文章中说,即使对这种新型材料加热,也不能消除已产生的变化。This suggests that the self-stiffening is not the result of chemical changes in the polymer, which can usually be undone by heat.这说明材料强度提高并不是聚合物发生化学反应造成的,一般这种变化在加热状态下是可逆的。The researchers do have one lead, though. Because of the regular alignment of the nanotubes, they were able to stress the material from various directions.不过研究人员已有所发现。由于碳纳米管呈规律状排列,他们能够从不同的方向对材料施加作用力。They found that when the direction of stress was at right-angles to the tubes, it stiffened by 5.9%.当施力方向与碳纳米管成直角时,材料硬度提高5.9%;When it was in the direction in which tubes were pointing, the increase was only 4.3%.当作用力与碳纳米管所指方向一致时,材料硬度仅提高4.3%。What that means is still unclear, but it may be the key to understanding the phenomenon—and thus being able to replicate it with other ingredients.现在尚无法对其中的原因作出解释,但或许对于理解材料硬度变化是非常重要的—进而在其他原材料身上复制这类变化也有了可能。 /201212/217570。
  • We may never know if the chicken or the egg came first, but scientists have discovered a fossil that sheds light on how turtles got their shells. Since the time of the dinosaurs, turtles have looked much the same as they do today, complete with boney shells. But scientists know turtles didnt just appear on the Earth fully formed.可能我们永远不会知道先有鸡还是先有蛋,但是科学家们发现的一个海龟化石揭示了它们是如何长出龟壳的?自恐龙时代起,海龟的外貌就跟现在相差无几,一样背着骨组织外壳。但是科学家们知道原始海龟的龟壳并没有发育完整。There must have been an ancestor with a partial shell or no shell at all. So how did the shell get there? Some dinosaurs and present day reptiles, like crocodiles, have boney skin plates called osteoderms. So researchers thought turtle shells might have evolved from these plates. The trouble was, when they studied turtle embryos, they found that shells grow out from the backbone and ribs and dont appear to be over-grown osteoderms.海龟的祖先中一定有只长出部分龟壳,或者根本没有龟壳的海龟。那么龟壳是如何长出来的?远古时代的恐龙和现在的爬行动物(比如说鳄鱼)都长有叫做“皮内成骨”的骨组织皮肤板块。因此研究者认为龟壳是从这种皮内成骨进化而来。问题是当他们研究海龟胚胎时发现,龟壳从脊椎骨和肋骨里长出,并没有参差不齐的骨化鳞片。The evolution of the shell remained a mystery until a 220- million-year-old fossil was unearthed in Ghizhou Province, China. The fossil was named Odontochelys semitestacea, or half-shelled turtle with teeth. Unlike modern land turtles, this sixteen-inch-long species was found with other marine reptiles, indicating it was aquatic. It had a plastron or lower shell.直到中国贵州省出土了一个2.2亿年前的海龟化石,龟壳进化的迷雾才被揭开。这个化石被命名为半甲齿龟。与现代的陆地海龟不同的是,这种长约16英尺的龟类与其他海洋爬行动物一同被发现,这表明它是水生动物。它长有龟板。But the upper shell, called a carapace, was not there, only a thickened backbone and ribs. Odontochelys not only answered some questions about the shells origin, it also gave a clue as to why a turtle has a full-body shell. Scientists think the shell evolved as a defense against ocean predators. On land, the belly is protected by the ground, but in an aquatic environment, turtles can be attacked from above or below. After the plastron evolved, the carapace developed, giving turtles extra protection.但是背部却没有壳(即没有甲壳),只有增厚的脊椎骨和肋骨。半甲齿龟不仅回答了龟壳起源的问题,还为海龟为什么长出完整龟壳提供了线索。科学家们认为海龟张出硬壳是为了防御海里的猎手。在陆地上有土地来保护肚皮,但是在水生环境里,海龟容易腹背受敌。龟板进化之后,甲壳也开始进化,这给了海龟更多的保护。原文译文属!201208/193157。
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