Science and Technology科技Solar heat for oil wells用于油井的太阳热能Mirrors in glasshouses…温室的反光镜…...…can be used to heat stones…...能用于加热石头THERE is a lot of energy from ancient sunshine stored in the oil that sits below the deserts of Oman.古代阳光的很多能量储存于埋藏在阿曼沙漠下的石油里。There is also a lot of sunshine hitting those deserts today.如今，还是有很多阳光照射在这些沙漠之上。A new wrinkle to an established technology should allow some of that current sunshine to be employed to get at more of the ancient stuff.不过，一项已确定的技术革新应该允许那部分如今的阳光能被用于从古老的原料中提取到更多东西。Using heat—in the form of steam—to liberate disobligingly thick and gunky oil which would otherwise stay in the ground is nothing new.运用热能---以蒸汽的形式---来释放（放出）不方便使用的浓厚而黏稠状的石油，否则这些石油会留在地下，这没什么新鲜的。Such enhanced-recovery techniques date back to the 1950s and 40% of Californias oil production now depends on steaming subterranean rocks in this way.这类提高的采收石油技术可以追溯到20世纪50年代。现如今，40%的加州石油产品就是以这种方式依赖热气腾腾的地下岩石生产而成。The steam, however, is made by burning other fossil fuels—normally natural gas—and because heating rock takes a lot of steam, making that steam takes a lot of money.然而，通过燃烧其它化石燃料来生产蒸汽---一般为天然气---而因为加热岩石需要很多蒸汽，所以生产蒸汽花费很大。It also adds to the oils climate footprint.它还增加石油的（气候变化）的碳排放量。The amount of gas used means that a barrel of Californian heavy oil gives the stuff from Canadas tar sands a run for its money in terms of associated greenhouse-gas emissions.根据相关的温室气体排放量，天然气的耗费量意味着每桶加州重油竭尽全力打败了加拿大沥青砂岩中提取的原油。GlassPoint, a small Californian company, thinks it can make steam for oil recovery more cleanly and cheaply by using sunshine to do the heating.加州的一家小公司---玻璃点太阳能公司认为，通过使用阳光来加热，它能为采油生产更清洁和更便宜的蒸汽。This sounds surprising.这听起来令人感到意外。Solar-thermal power stations, which employ mirrors to concentrate sunlight on boilers and thus raise steam to generate electricity by turning turbines, are far from cheap compared with gas-fired stations.太阳能热发电站利用反光镜将太阳光集中到锅炉上，因而提升蒸汽转动涡轮机来产电，与燃气站相比一点也不便宜。But solar-thermal electricity faces exacting challenges.然而，太阳能热发电面临严峻的挑战。To feed a turbine you need particularly pure steam, which can be a problem if you are in a desert.为了给涡轮机提供特别需要的纯蒸汽，如果在沙漠里的话，这可能是个问题。And to get the most out of the system you need the steam to be both very hot indeed and available in copious amounts.而且为了从这个系统中得到最多，确实需要非常高温的蒸汽而且要用的量很大。Oil wells, GlassPoints founders noticed, are far less demanding consumers in these respects. 玻璃点太阳能公司的创始人注意到，在这些方面，油井是要求少的多的消费者（消耗者）。The steam used can be comparatively dirty.Nor does it have to be infernally hot.相比之下，使用的蒸汽可以脏些，温度也不需要过高。And even a small amount of it, added to an existing gas-based recovery process, can make a useful contribution.而且，甚至添加少量的蒸汽到现有的以天然气为基础的采油过程也能产生作用。There are, though, disadvantages to having to work in an oilfield.虽然，如果必须在油田运用蒸汽的话，确实有些不利条件。People building solar-thermal power stations prefer sites low in dust.人们喜欢在粉尘量低的位置建造太阳能热发电站。Those serving the oil industry must go where the rigs are, however dusty and mucky the air.无论空气尘土多大，多么肮脏，为石油工业务的人们必须跟随钻井走。GlassPoint seems to have found a neat solution to this: it puts its mirrors indoors. Greenhouses are easy to buy, quick to erect and, thanks to off-the-shelf kit designed for the purpose, simple to keep clean, too.玻璃点太阳能公司似乎已经为此找到了一套干净利落的方案：把反光镜放在室内。由于为建温室目的而设计现成的成套用品，人们很容易购买到温室，很快就能建造起来，而且保持清洁也很简单。Moreover, sheltering the mirrors from the wind allows those mirrors to be a lot lighter, making them both cheap to build and ship, and easier to turn in order to follow the sun.此外，为保护反光镜免受风的侵蚀，准许这些反光镜重量要轻的多，使得它们既建造便宜也容易运输，而且为了跟进太阳而更容易转向。GlassPoints boss, Rod MacGregor, thinks that taking capital costs and the lifetime of the plant into account his firm can produce steam at .78 per million British thermal units (btu), which is .58 a gigajoule.玻璃点太阳能公司的老板罗德?麦格雷戈（Rod MacGregor）认为，考虑到工厂的资金成本和历史，他的公司能产生蒸汽每百万英（制）热单位（BTU）3.78美元，这是每千兆焦耳3.58美元。Steam from gas comes in at .79 per million btu.天然气加热的蒸汽达到每百万英（制）热单位（BTU）5.79美元。A pilot project in California, he says, has been producing steam as intended since the beginning of the year.他说，自年初以来，加州一个实验项目已经产生了预期的蒸汽。And the company has now signed a deal with Petroleum Development Oman for 7 megawatts of plant—a 16,000-square-metre greenhouse providing some 57 billion btu of steam a year.而且该公司现在已经与阿曼石油开发公司签署了7兆瓦工厂的协议---一个16000平方米的温室，每年大约提供570亿百万英（制）热单位（BTU）的蒸汽。If it pans out, the technology could sp fast.如果这个实验项目发展开来的话，那么这项技术可能会传播很快。Mr MacGregor expects Oman to be using 200 trillion btu of steam a year for oil recovery by 2015.麦格雷戈先生预计，到2015年为止，阿曼石油开发公司每年可以使用200万亿每百万英（制）热单位（BTU）蒸汽来开采石油。Not all of that steam could be solar, but a system which used high-pressure solar steam during the day and low-pressure gas-generated steam by night, to keep the pipes hot, might get 80% of its power from the sun.并非所有的蒸汽来自太阳能，而是来自一个系统。白天，这个系统使用高压太阳蒸汽，而晚上使用低压天然气产生的蒸汽，保持管道热乎，或许80%能量可从太阳光获得。That would free up a lot of gas for export—or for turning into petrochemicals.这将可以得到很多天然气用于出口---或用于转变成石油化学制品。Enhanced oil recovery currently uses a quite remarkable amount of energy: 1.7 quadrillion btu of gas around the world every year, according to GlassPoint.目前，提高石油开采使用相当大的能量：根据玻璃点太阳能公司所述，每年，世界各地需要使用1.7×1015每百万英（制）热单位（BTU）的天然气。Not all of that is in sunny places, but there are many deserts besides Omans that have oil beneath them.并不是所有天然气都在阳光充足的地方，但是，除了阿曼沙漠下面有石油外，许多沙漠下都有石油。The paradoxical possibility, then, is that solar-thermal technology might end up producing a lot more oil than electricity in the years to come.然而，自相矛盾的可能性是，在未来几年里，太阳能热技术最终可能生产许多石油，而不是电。 /201211/209591Science and Technology Prevention of cancer Wonder drug科技 预防癌症 特效药Aspirin continues to amaze阿司匹林让人吃惊的另一面FOR thousands of years aspirin has been humanitys wonder drug.几千年来，阿司匹林就一直是人类的特效药。Extracts from the willow tree have been used for pain relief in folk medicine since the time of the ancient Greeks.从古希腊开始，在民间医药中，人们就用柳树的萃取物缓解疼痛。By 1897 a synthetic derivative (acetyl salicylic acid) of the plants active ingredient (salicin) was created. This allowed aspirin to become the most widely used medicine in the world.1897年，这种植物中的有效成分的人工合成衍生物诞生了，于是阿司匹林变成了世界上应用最广泛的药品。In recent years its benefits as a blood-thinning drug have led to it being prescribed in low doses of around 50mg to reduce deaths from stroke and heart attack.最近几年，由于阿司匹林的防血凝功能，在用其治疗中风和心脏病的时候，剂量很小，维持在50mg的水平左右。There were also hints that aspirin may help prevent some cancers.也有迹象表明阿司匹林可以帮助预防一些癌症。But these were mostly based on observational studies, which can be misleading.不过这些结论大多都是在观察研究的基础上的，因而有可能产生误导。The gold standard of scientific evidence is the randomised controlled trial, preferably one with a lot of people and held over a long time.国际上科学据的标准是由随机对照实验得出的结果，尤其是那些有很多人参与又经过很长时间的实验。The results of just such a trial, published in the Lancet, suggest that aspirin is indeed an astonishing drug.而就是这样一份发表在《柳叶刀》上的论文表示阿司匹林的确是一种让人吃惊的药物。Peter Rothwell at the John Radcliffe Hospital in Oxford and his colleagues looked at deaths due to cancers during and after randomised trials of daily aspirin.来自牛津的约翰·拉德克里夫医院的彼得·罗思韦尔（Peter Rothwell）和他的同事们研究了在每日用阿司匹林的随机对照实验期间或者之后因癌症而死亡的病例。The trials had actually been started to look at how useful aspirin was for preventing heart attacks and strokes. Nevertheless, the data from the 25,570 patients enrolled in eight trials was also revealing about cancer.这一实验本是为了研究阿司匹林在防止心脏病和中风方面的疗效的，然而八项试验25570名患者的数据也揭示了阿司匹林对于癌症的疗效。In trials lasting between four and eight years, the patients who had been given aspirin were 21% less likely to die from cancer than those who had been given a placebo.在那些历时4到8年之间的实验中，用阿司匹林的患者因癌症而死亡的概率比那些用安慰剂的患者小了21%。These results were based on 674 cancer deaths, so are unlikely to represent the kind of statistical oddity that can beset studies on cancer risks that sometimes create headlines.这些结果是在674例癌症死亡病例的基础上得出的，所以不大可能是所谓的统计学上的例外。对癌症风险的研究会因这种例外而受挫，有时甚至会闹成大新闻。The benefits of aspirin were also apparent many years after the trials had ended.试验结束后的很多年后，阿司匹林的效果也仍旧明显。After five years, death rates for all cancers fell by 35% and for gastrointestinal cancers by 54%.五年后，所有癌症的死亡率下降了35%，而胃肠道癌症的死亡率则下降了54%。A long-term follow-up of patients showed that the 20-year risk of cancer death remained 20% lower in those who had taken aspirin.一项长期的病情跟踪报告显示，那些用阿司匹林的患者的20年内的癌症死亡风险比那些不用的低了20%。The study revealed that the effect takes time to accrue, so aspirin must be taken over a long period.这项研究揭示了阿司匹林的效果是随着时间而递增的，所以必须长期用才行。The latent period for improving oesophageal, pancreatic, brain and lung cancer was about five years of aspirin taking on a daily basis.For stomach and colorectal cancer the effects took ten years and for prostate cancer about 15 years.每日用阿司匹林对改善食管癌，胰腺癌，脑癌和肺癌的潜伏期为5年，对胃癌和结直肠癌则要花10年才能起作用，而前列腺癌则要15年。The means by which aspirin prevents cancer is not well understood.这意味着目前还不清楚阿司匹林到底是怎么预防癌症的。It is believed that it inhibits an enzyme that promotes cell proliferation in tumours.研究人员认为阿司匹林阻碍了一种在肿瘤内部促进细胞增殖的酶的活动。The researchers also found that small daily doses of aspirin were enough, and that taking more than 75mg conferred no additional benefits.研究者还发现，每天用小剂量的阿司匹林就已足够，剂量超过75mg后不会再增加效果。Those starting on aspirin in their late 40s or 50s benefit most.那些从四五十岁末就开始用阿司匹林的人得到的效果最好。Current guidelines on using aspirin for reducing the chances of a stroke or heart attack rightly warn of the small risk of ulcers and of dangerous bleeding in the stomach.目前在用阿司匹林治疗中风或者心脏病时，用药说明上会明确提醒有可能出现溃疡和危险性胃出血。These guidelines will probably have to be revised given the new findings.而鉴于这些新发现，这些说明很可能将要被修改了。However, it remains unlikely that popping aspirin will be recommended for everyone like a vitamin supplement.不过阿司匹林泡腾片不大可能像维生素补充剂一样被推广至每一个人。Aspirin is a highly cost-effective treatment: taking it for five to ten years easily beats initiatives to screen for breast and prostate cancers.用阿司匹林是一种非常划算的治疗：只要吃五到十年，就能打败那些让你做乳腺癌或者前列腺癌扫描的建议。To put it another way, ask yourself what a pharmaceuticals firm might charge for a drug that would reduce the chance of death by cancer by 20%—and then note that 100 days supply of low-dose aspirin can cost less than a dollar.换种说法，问问你自己，什么样的医药公司在看到100天的小剂量阿司匹林供应量还值不到一美元时，会对这种能够减少20%癌症死亡几率的药品开价呢？By anyones measure, that is a bargain.不管按照哪一方的标准，这都是一笔非常划算的交易。 /201301/220406
Have you ever noticed that while it’s pretty easy to tell your dog is sick, it’s much harder to know how your cat or bird are feeling? Well, before you start asking your dog why it can’t be more stoic like animals half its size, it’s probably worth considering each animal’s place in the food chain.你有没有注意到发现是否生病很容易，但想知道猫或鸟的感受就比较难了。在你问“为什么不能比身材不及它一半的动物更坚强”之前，应该思考一下在食物链中的位置。You see, the lower down the food chain you are, the more important it is for you to hide any sign of illness. Obvious illness or pain function as red flags for predators. You may as well wear a sign saying, “Easy meal, guys. Come and get me.”要知道，在食物链的位置越低，隐藏疾病的任何征兆就越重要。明显的疾病或疼痛对食肉动物来说是危险的信号。就好像你身上有这样的标语“容易到手的午餐，伙计们，快来吃我吧”。Now, even small dogs are genetically programmed to function like predators, which makes sense considering they are close relatives of wolves. And birds–you can probably figure out why the only way you’d find out your bird is sick is when it dies. The situation with cats, as compared to dogs and birds, is much more interesting. On the one hand, cats are predators, but on the other, they’re small enough to be prey.现在，即使是很小的也由基因决定了是肉食动物。所以把看作狼的近亲也是有道理的。至于鸟类，也许能知道它是否生病的唯一途径就是死亡。而猫的情况与和鸟相比，就更有趣了。一方面，猫是食肉动物；另一方面，它们身材矮小很容易被捕食。So how can you tell if your smaller pets need medical attention? For one thing, trust your hunches. No one knows your pets like you do, so if you notice even very subtle changes in habits and behavior, you may want to have a vet look them over. For a cat, other signs of illness might be that it has stopped grooming, is losing weight, vocalizing more or less than usual, or missing the litter box.所以你要怎样判断宠物需要医药治疗呢？首先，相信预感。没有人比你更了解你的宠物。当你注意到它们生活习惯上尽管是非常微小的变化，也要请兽医对其进行检查。而猫生病的其它征兆，可能就是精神不振，食欲不佳等症状。 /201303/231706
Youre on the deck catching rays, and even though you know you arent supposed to tan without sunblock, you figure youll be able to tell if you start to get really burned. Sure enough, after a little while you can see a redness coloring your skin, but it doesnt look too bad. Five or six hours later, the real burn begins appearing, and its too late now to stop it.你在甲板上沐浴阳光，即使你能看到，不涂防晒霜时你没被晒黑，但你不会觉察到皮肤从何时起被晒伤。果然，过一会你的皮肤开始变红，但是看起来红得并不厉害。五六个小时候，你感到皮肤在灼烧，但为时已晚。What just happened is a kind of pump-fake from the system that runs temperature-balance in your body. People often assume its possible to watch sunburn mounting on your skin, but this is a serious mistake. The red coloration that comes after an hour or so is not the first signs of tanning at all; that redness is caused by an increased flow of blood toward the skin due to excess body heat.刚发生的现象是一种假象，与你身体内维持体温恒定的系统有关。通常人们误以为皮肤烧伤时会有看得见的痕迹。但这种想法大错特错。一小时左右后皮肤泛红，这根本不是皮肤被晒黑的第一个迹象：皮肤呈现红色是因为身体过热致使流向皮肤的血液增多。Its the same effect that gives people a ruddy glow after exercise: the over-heated body attempts to just its temperature by directing more blood toward its surfaces, which has the effect of radiating away heat. This ;flush; will disappear as soon as you cool down. Therefore, its no indication as to whether the skin itself is becoming burned.这跟运动之后人们满面红光是同一个道理：身体过热，血液流向表面的皮肤以保体温恒定，同时放出热量。在身体凉快之后脸上的红光立刻褪去。因此，没有迹象表明皮肤自身是否在灼烧。The redness of a burn looks the same because its also caused in part by increased blood flow——but with an actual burn, the blood is being shunted outward much more rapidly in an effort to repair aly damaged cells. By the time the blood starts being sent to the aid of your traumatized skin, several hours have elapsed since that deceptive ;first blush; has faded. Its only then that you can start to feel how much or how little burn you actually received.晒伤的红色跟这看起来很像，因为晒伤后皮肤呈现红色部分是因为血流量增多，但真正烧伤时，会有更多的血液快速分流到体表，以修复已经损伤的细胞。然而，“第一次泛红”的假象消失了好几个小时之后，血液才开始修复损伤的皮肤。直到这时你才能感觉到皮肤烧伤的程度。原文译文属！201209/198867Few have witnessed this moment, for the male, his only tender encounter in the otherwise solitary life . But it doesnt last long , a rival suitor has also caught the female scent ,catch ,pass me ,put on hold, he must fight for his rights.He sees off the first challenge without injury to either party,but bloodier battles are to come. Another battle won, though he has been slightly injured ,he headed back to his mate, but now she seems to have lost enthusiasm, female polar bears are high maintenance .Wherever she goes ,she will follow ,mating with her when she allows and guarding her at all times .Over the next two weeks, the male sees off many rivals ,but the battles take that toll of them ,he is almost spent, but he isnt sure that no other bear has mate it with his female.有一些动物目睹了这一刻,而那位追逐的男性,他唯一的温柔遇到离群索居的生活。但这不会持续太久,对手也被女性的香味吸引,要想过去就必须过我这关,他要为自己的权利而战。他的第一个挑战没有让他受伤,但血腥的战斗马上就要来到。赢得了另一场战斗,尽管他稍微受了一点伤,他仍然朝伴侣走去,但现在她似乎已经失去了,因为母北极熊极为高调。无论她走到哪儿,他都会跟随,交配,她会允许及保护她。接下来的2周,男性将会同许多对手战斗,人数上不占优势，而且他几乎精疲力竭,但他并不确定其他的熊是否对他的伴侣感兴趣。注：听力文本来源于普特201201/167297