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时间:2019年11月17日 08:02:11

The letter has finally arrived welcoming you as a member of the class. Youre about to become a college freshman.欢迎你成为新生一员的厚厚的信终于到了,你将成为大一新生了。Half of college education has to come from the student. But how? College counselors, faculty advisers and one very successful student offer the following tips on how to get the most out of your college education.大部分学生上大学都期望离校时获得学士学位,但怎样做到这点呢?一些高校辅导员、指导教师以及一名极为成功的学生,对如何充分利用高校教育提出了以下建议。Involvement积极参与The most successful students are those actively involved in their education, interacting with classmates and faculty and participating in activities. You become part of the college community, developing support groups that you can turn to for help. Get involved, but not over committed. In the first term, focus on adjusting to the academic demand.最成功的学生是那些积极参与自己所受教育的学生。他们与同学和教师交流,参加各项活动。你要成为学校集体的一份子,发展自己可以寻求帮助的团体。参与,但不过分投入。在第一学期,着重于使自己适应大学的学业要求。Time management时间安排“Man is first social animal, then a rational one.” Says a professor at purdue university. So you may find it hard to say”no” each time your roommate wants to see a movie when you need to paradise lost.“人首先是一种社会性动物,然后才是有理性的人,”普渡大学的一位教授说。因此,每当你的室友想要看电影而你却很想读《失乐园》时,你都很难对他说“不”。College is known for its distractions. In those first months, youll meet people whose values and priorities are different from yours.大学素有各种活动。在最初几个月,你会遇到很多人,他们的价值观以及优先考虑的事与你不同。201303/231163

June. Nineteen sixty-nine. Not one airliner but two, plus the pilot of an Air National Guard fighter plane, report being harassed by a team of UFOs. One man estimates the glowing ships have come within a few hundred feet. The pilot of the fighter plane even declares a near-collision. 一九六九年六月。两个航班和国民警卫队空军战机的飞行员报告称,他们受到一队不明飞行物的侵扰。其中一个人估计,发光的不明飞行物距离他们只有几百英尺。战机飞行员甚至宣称他们发生了近距离的擦撞。What were these UFOs really? It turned out they were fragments of a meteor coming apart in the upper atmosphere. Now heres the most interesting part: the meteor fragments were at least one hundred and twenty five miles from the planes. How could you possibly think something over a hundred miles away was about to hit you?这些不明飞行物到底是什么?原来,它们是来自高空大气层中的流星碎片。有趣的是,流星碎片距离飞机至少有一百二十五公里。你能想像得到一百多英里之外的东西可以撞到你吗?Objects in the sky confuse our perceptual abilities. With no visual cues to help calculate distance, our brains rely on size and speed instead. How? By using a simple fact: far-away things look like they are going slower than close-up things. You may have noticed this when driving: those distant phone poles pass sluggishly while the ones on the road go zooming by. In a blank white sky, our brains default to a simple strategy: the bigger it looks and the faster it goes, the closer it probably is.天空中的物体能够混淆我们的感知能力。没有视觉线索来帮助计算距离,我们的大脑只能依赖于物体的尺寸和速度。怎么依赖?这有一个简单的事实:远距离物体看起来比近距离物体的移动速度要慢。当你驾驶汽车时,你可能注意到了这样的事实:那些遥远距离的电话杆掠过车窗的速度很缓慢。在空旷的天空,我们的大脑默认了一个简单概念:物体体积越大,速度越快,它可能就距离我们越近。This is a smart way to proceed, and it generally works. Still, our perception can be fouled by rare situations in which we find ourselves looking at something far away that nevertheless moves extremely fast, such as an incoming meteor. At thousands of miles an hour, that flaming object speeds across your field of vision, and your brain can easily conclude it must be much closer than it is--maybe even about to abduct you. 这种推理方式很聪明、也很有效。尽管如此,在罕见的情况下比如当我们看到远处高速移动的物体(例如流星碎片)时,我们的感知能力仍然会受到影响。但一个发光物体以数千英里的时速划过你的视野时,你的大脑可以很容易地得出这样的结论:它距离我太近了;;可能是要绑架我。201203/174958

Science and technology.科技。Parasitology寄生虫学The risks of global worming全球防虫的危险Widesp use of anti-parasite drugs is reducing their value广泛使用抗寄生虫药物正在降低其疗效Safely grazing?正在安全地吃草?FOR decades, the overuse of antibiotics has encouraged the evolution of drug-resistant bacteria which, though they have never broken out and caused an epidemic in the way that was once feared, have nevertheless been responsible for many deaths that might otherwise have been avoided. Now something similar seems to be happening in agriculture. The overuse of drugs against parasitic worms which infest stock animals means that these, too, are becoming drug-resistant. That is bad for the animals health and welfare, and equally bad for farmers profits.几十年来,广泛使用抗生素促进了耐药病菌的进化。尽管它们从来没有失控,爆发人们一度为止恐惧的大规模瘟疫,但还是造成了大量本来可以避免的死亡。现在畜牧业中似乎也有类似现象。人们对家畜身上的寄生虫过分使用药物,这让它们也有了抗药性。这对动物的健康与安乐绝非好事,同样也会减少饲养它们的农民的利润。This, at least, is the conclusion drawn by Ray Kaplan, a parasitologist at the University of Georgia who has just published a review of research on the problem. His results, which appear in Veterinary Parasitology, make grim ing.这至少是乔治亚大学(University of Georgia)寄生虫病学家雷?卡普兰(Ray Kaplan)在他最近发表的有关这一问题的研究综述中得出的结论。他发表在《兽医寄生虫学》(Veterinary Parasitology)上的文章读来让人心情沉重。Sheep and goats are the worst affected. Studies in Australia, Brazil and the ed States suggest that animals in half or more of farms in many parts of those countries are infested with drug-resistant worms. In some cases the parasites are resistant to every drug that can be thrown at them. The proportion of infested farms is lower in New Zealand, a country that has a huge population of sheep, but even there it is rising at a worrying rate.绵羊与山羊受的影响最大。在澳大利亚、巴西和美国所做的研究表明,在这些国家的许多地区,一半或更多的农场中的家畜身上有耐药寄生虫。有些农场的寄生虫对所有可用药物有抗药性。新西兰的农场饲养着大量绵羊,它们受到影响的比例比较低;但即使在该国,受影响农场比例的增长速度还是令人担心。Cattle, too, are afflicted. Dr Kaplan cites work done in Argentina, Brazil and New Zealand. And horses suffer as well, with resistant worms turning up in both America and Europe.家牛也身受其害。卡普兰士引用了在阿根廷、巴西和新西兰所做的研究工作。马也是受害者,美国与欧洲的马身上都发现了抗药寄生虫。The root of the problem is what Dr Kaplan refers to as ;global worming;-giving drugs prophylactically to all livestock rather than reserving them for use as a treatment when an animal actually becomes infested. It is common sense, of course, to try to prevent infestation rather than merely treating it once it has arisen.问题的根源是卡普兰士称为;全球防虫;的现象——预防性地对所有家畜用药,而不是在动物身上真正出现了寄生虫时投药治疗。当然,防病胜于治病是常识。Unfortunately, such promiscuous use of drugs is the best way to put selection pressure on the worms and encourage the evolution of resistant strains.不幸的是,这样的预防性用药是在寄生虫身上施加选择压力的最佳方法,能够促进抗药品种的进化。What is needed, says Dr Kaplan, is more selective drug use, and better management. Worms are not evenly distributed. Instead, a minority of animals play host to most of them. Aiming treatment at those animals would reduce the likelihood of resistance emerging without harming a farmers ability to control infestations. Better husbandry might help, too. Not grazing so many animals on a given patch of land would discourage transmission.卡普兰士认为,现在需要做的是加强管理与更有选择性地用药。寄生虫并非均匀寄生在各种动物身上。有少数动物是大多数寄生虫的寄主。集中治疗这些动物则会降低耐药性发生的可能性,同时也不会损害农民控制虫害的能力。改进饲养方法或许也有益处。不在一块草地上过量放牧动物会减轻虫害传播。That, though, would bring problems of its own, as it would reduce the number of animals which could be raised on a given farm. Which leads to the nub of the issue: it is hard to work out exactly how much damage resistant worms are doing, and thus how much effort should be put into trying to stop the sp of resistance-not least because, as Dr Kaplan found out when he conducted his survey, the data are pretty sporadic. But they are worrying enough to be worth following up, for if resistance did get out of hand the consequences could be very expensive indeed.但这本身也会带来问题,因为这会减少一座农场能饲养的家畜数目。这就引出了问题的症结:人们很难确定抗药寄生虫会造成多大的危害,因此也不知道该花多少代价来阻止抗药性蔓延,因为很重要的是,卡普兰士在纵观研究结果时发现有关数据相当零散。但这些数据还是很令人忧虑,值得进一步跟踪,因为一旦人们无法控制抗药性,就确实可能会付出惨重的代价。No one farmer is to blame. This is a tragedy of the commons, in which sensible individual decisions have led to a collective difficulty. But it might behove farmers to think more about how they use anti-worm drugs. If they do not, they may find that those drugs have become useless.无法就此责备某个农民。这是一个公地悲剧 [注],许多明智的个人决定导致了群体的困难。但或许农民们有责任多想想他们应该如何使用抗寄生虫药物。如果放弃这一责任,他们或许有一天会发现这些药物变得全然无用。 201208/193574


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