Unit 1 Genetically modified foods -- Feed the World?
If you want to spark a heated debate at a dinner party, bring up the topic of genetically modified foods. For many people, the concept of genetically altered, high-tech crop production raises all kinds of environmental, health, safety and ethical questions. Particularly in countries with long agrarian traditions -- and vocal green lobbies -- the idea seems against nature.
如果你想在某次晚宴上挑起一场激烈的争论,那就提出转基因食品的话题吧。对许多人来说,高科技的转基因作物生产的概念会带来诸如环境、健康、安全和伦理等方面的各种问题。特别是在有悠久的农业生产传统和主张环保的游说集团的国家里,转基因食品的主意似乎有悖自然。
In fact, genetically modified foods are already very much a part of our lives. A third of the corn and more than half the soybeans and cotton grown in the US last year were the product of biotechnology, according to the Department of Agriculture. More than 65 million acres of genetically modified crops will be planted in the US this year. The genetic is out of the bottle.
事实上,转基因食品已经成为我们生活重要的一部分。根据农业部的统计,美国去年所种植玉米的1/3,大豆和棉花的一半以上都是生物技术的产物。今年,美国将种植6500多万英亩的转基因作物。基因妖怪已经从瓶子里跑出来了。
Yet there are clearly some very real issues that need to be resolved. Like any new product entering the food chain, genetically modified foods must be subjected to rigorous testing. In wealthy countries, the debate about biotech is tempered by the fact that we have a rich array of foods to choose from -- and a supply that far exceeds our needs. In developing countries desperate to feed fast-growing and underfed populations; the issue is simpler and much more urgent: Do the benefits of biotech outweigh the risks?
但是,显然还有一些非常现实的问题需要解决。就像任何一种要进入食物链的新食品一样,转基因食品必须经过严格的检验。在富裕的国家里,由于有大量丰富的食品可供选择,而且供应远远超过需求,所以关于生物技术的争论相对缓和一些。在迫切想要养活其迅速增长而又吃不饱的人口的发展中国家,问题比较简单,也更加紧迫:生物技术的好处是否大于风险呢?
The statistics on population growth and hunger are disturbing. Last year the worlds population reached 6 billion. And by 2050, the UN estimates, it will probably near 9 billion. Almost all that growth will occur in developing countries. At the same time, the worlds available cultivable land per person is declining. Arable land has declined steadily since 1960 and will decease by half over the next 50 years, according to the International Service for the Acquisition of Agri-Biotech Applications (ISAAA).
关于人口增长和饥饿的统计数字读来令人感到不安。去年,世界人口达到了60亿。联合国预测,到2D0年,这个数字很可能将接近90亿,而增加的人口几乎都来自发展中国家。与此同时,世界人均耕地正在减少。国际农业生物工程应用技术采购管理局(ISAAA)称,自1960年以来,耕地面积一直持续下降,并将在今后50年减少一半。
The UN estimates that nearly 800 million people around the world are undernourished. The effects are devastating. About 400 million women of childbearing age are iron deficient, which means their babies are exposed to various birth defects. As many as 100 million children suffer from vitamin A deficiency, a leading cause of blindness. Tens of millions of people suffer from other major ailments and nutritional deficiencies caused by lack of food.
联合国估计,世界上有近8亿人口营养不良。它产生的效应是破坏性的。大约有4亿的育龄妇女体内缺铁,也就是说,她们的婴儿将可能有各种天生的缺陷。数量多达1亿的儿童缺乏维生素A,这是导致失明的主要原因。还有数千万的人患有因食物匮乏而导致的其他严重疾病和营养不良症。
How can biotech help? Biotechnologists have developed genetically modified rice that is fortified with beta-carotene -- which the body converts into vitamin A -- and additional iron, and they are working on other kinds of nutritionally improved crops. Biotech can also improve farming productivity in places where food shortages are caused by crop damage attribution to pests, drought, poor soil and crop viruses, bacteria or fungi.
生物技术对此能做些什么呢?生物技术专家已经培育出了含有β—胡萝卜素(身体可将之转化为维生素A)和更多铁元素的转基因水稻,目前正在研究培育其他一些增进营养成分的农作物。生物技术还可以帮助提高因虫害、干旱、土壤贫瘠和作物病毒、细菌或真菌导致作物减产而出现食物匮乏的地区的农业生产率。
Damage caused by pests is incredible. The European corn borer, for example, destroys 40 million tons of the worlds corn crop annually, about 7% of the total. Incorporating pest-resistant genes into seeds can help restore the balance. In trials of pest-resistant cotton in Africa, yields have increased significantly. So far, fears that genetically modified, pest-resistant crops might kill good insects as well as bad appear unfounded.
虫害带来的损失令人难以置信。例如,欧洲玉米螟每年毁掉4000万吨玉米,占世界玉米总产量的7%。把抗虫害的基因植入种子可以帮助避免这一损失。在非洲进行的抗虫害棉花试验中,棉花的产量已大幅度提高。有人担心,抗虫害的转基因作物不仅将害虫杀死,而且有可能连益虫也一起杀死,但到目前为止,这种担心似乎没有根据。
Viruses often cause massive failure in staple crops in developing countries. Two years age, Africa lost more than half its cassava crop -- a key source of calories -- to the mosaic virus. Genetically modified, virus-resistant crops can reduce that damage, as can drought-tolerant seeds in regions where water shortages limit the amount of land under cultivation. Biotech can also help solve the problem of soil that contains excess aluminum, which can damage roots and cause many staple-crop failures. A gene that helps neutralize aluminum toxicity in rice has been identified.
病毒常常在发展中国家造成主要粮食作物的大面积歉收。两年前,花叶病毒使非洲损失了超过一半的木薯,而这种作物是当地人的主要食物。转基因的抗病毒作物可以减少这种损失,就像抗干旱种子在可耕地面积因缺水而受到限制的地区起到的作用一样。含铝过高的土壤会损伤作物的根系并使许多主要作物歉收,对于这种问题生物技术也能帮助解决。目前,研究人员已经识别出一种有助于中和水稻里铝的毒性的基因。
Many scientists believe biotech could raise overall crop productivity in developing countries as much as 25% and help prevent the loss of those crops after they are harvested.
许多科学家认为,生物技术能够把发展中国家的农业总产量提高25%,并且帮助防止作物收割后遭受损失。
Yet for all that promise, biotech is far from being the whole answer. In developing countries, lost crops are only one cause of hunger. Poverty plays the largest role. Today more than 1 billion people around the globe live on less than 1 a day. Making genetically modified crops available will not reduce hunger if farmers cannot afford to grow them or if the local population cannot afford to buy the food those farmers produce.
尽管具有这么多潜力,生物技术还远远不能解决全部问题。在发展中国家,作物歉收只是造成饥饿的一个原因。贫穷才是罪魁祸首。今天,全世界有超过10亿人口每天靠不到1美元维持生计。如果农民没钱种植转基因作物或当地人买不起农民种出的粮食,培育转基因作物就无法减少饥饿。
Nor can biotech overcome the challenge of distributing food in developing countries. Taken as a whole, the world produces enough food to feed everyone -- but much of it is simply in the wrong place. Especially in countries with undeveloped transport infrastructures, geography restricts food availability as dramatically as genetics promises to improve it.
此外,生物技术也无法克服在发展中国家分配粮食的难题。从整体上看,世界生产的粮食足够养活所有人,但大部分粮食却不是在需要的地方。尤其在运输基础设施落后的国家,地理条件对食物供给的限制正如遗传学为食物供给带来的希望一样大。
Biotech has its own "distribution" problems. Private-sector biotech companies in the rich countries carry out much of the leading-edge research on genetically modified crops. Their products are often too costly for poor farmers in the developing world, and many of those products won even reach the regions where they are most needed. Biotech firms have a strong financial incentive to target rich markets first in order to help them rapidly recoup the high costs of product development. But some of these companies are responding to needs of poor countries. A London-based company, for example, has announced that it will share with developing countries technology needed to produce vitamin-enriched "golden rice".
生物技术也面临自身的“分配”问题。许多转基因作物方面的尖端研究都是富国的私营生物技术公司进行的。对发展中国家的穷苦农民来说,这些公司的产品通常显得过于昂贵,而且这些产品中的大部分甚至无法到达最需要的地区。强大的经济刺激促使生物技术公司把富裕国家的市场作为第一目标,以便能够尽快回收产品开发的高额成本。不过,有些公司已开始对贫穷国家的需要做出反应。例如,一家总部在伦敦的公司已经宣布,它愿意和发展中国家一起分享生产维生素增强型的“金水稻”所需的技术。
More and more biotech research is being carried out in developing countries. But to increase the impact of genetic research on the food production of those countries, there is a need for better collaboration between government agencies -- both local and in developed countries -- and private biotech firms. The ISAAA, for example, is successfully partnering with the US Agency for International Development, local researches and private biotech companies to find and deliver biotech solutions for farmers in developing countries.
发展中国家正在进行越来越多的生物技术研究。但是,为扩大遗传学研究对这些国家的粮食生产的影响,政府各部门(包括当地政府部门和发达国家的政府部门)与私营生物技术公司之间需要更好的合作。例如,国际农业生物工程应用技术采购管理局目前正与美国国际发展署、当地的研究人员以及私营的生物技术公司进行成功的合作,以帮助发展中国家的农民寻求生物技术方面的解决办法。
Will "Franken foods" feed the world? Biotech is not a panacea, but it does promise to transform agriculture in many developing countries. If that promise is not fulfilled, the real losers will be their people, who could suffer for years to come.
“弗兰肯食品”能养活世界吗?生物技术虽不是万灵药,但它确实有希望改造许多发展中国家的农业。如果这种希望不能实现,真正的受害者将是这些国家的人民,他们可能会在未来的岁月里遭受苦难。
Unit 2 The Biology of Skin Color:Black and White
之前当时在西澳大学的人类学家Nina Jalonski被要求做一项关于人类皮肤的演说。作为灵长类进化研究的专家,她决定对肤色的进化史研讨一番,可是当她对课题进行文献研究时,结果却使她倍感失望。在1970年之前的较为新的理论都存在种族主义,而另外的文献则相当缺乏说服力。比如,有研究发表说白色皮肤可以更好的抵御寒冷。1970年之后,研究人员渐渐认识到对于研究皮肤这样的课题变的无足轻重,因为这样的研究总是收获甚微。Jalonski说:这个事实人人皆知,只是无人再议而已。
不久之后,Jablonski和她的丈夫Geoge Chaplin(一位地理信息系统专家)发表了第一份综合性肤色论。该文章发表于人类进化日报中,该文章说明了肤色与全球光线强度之间存在强烈且可预测的关联。但同时他们的发现也产生了一个深层次且令人吃惊的结论:肤色与维他命存在密切的联系。
作为加利福尼亚学术研究部门的领导,Jablonski首先假设我们最早的人类祖先有着与大猩猩(生物学角度最密切)类似的皮肤。在450万年到200万年以前,早起人类从热带雨林中脱离,开始走向非洲东部大草原。在以前的大草原上,人们不仅仅要更多的暴露于阳光下,而且他们忙于收集食物。哺乳动物的大脑非常害怕过热,只需要5、6个级别的热量就能使他们中暑,因此我们祖先不得不发明更好的解暑办法。
答案很简单,那就是通过蒸发带走热量。早起人类可能汗腺极少就像大猩猩一样,汗腺可能主要集中于他们的手掌中和脚底。然而有时,某些个体会比通常的个体长更多汗腺。这些汗腺更多的人,他们可以在热量驱逐他们躲在阴凉下之前有更长的时间去找食物。因此他们能得到更多食物,使得他们能孕育更健康的后代,并且将发达的汗腺遗传给后代。
在几百万年的自然选择后,人类的身体上已经拥有大约200万个汗腺。人类的皮肤相对于大猩猩的毛减少许多。加利福尼亚大学的人类学家Adrienne Zihlaman说:这样使得我们人类在沐浴后毛发干燥的更快。
然而,缺少毛发的皮肤非常容易遭到紫外线的破坏。科学家提出了一种假说:人类的肤色由黑色素所决定,而黑色素可以吸收或者分解紫外线。但是紫外线是什么呢?一些研究人员只出它是皮肤癌的起因。癌症通常是由于人体的恶性增殖,是由日常生活习惯引起的。还有一些事实表明阳光晒过的乳腺将影响女性哺乳,但是较为黝黑的皮肤可以有效保护这些哺乳女性。
Jablonski在澳大利亚准备演讲期间,她曾做过关于紫外线对叶酸(一种维他命B的混合物)的影响的研究。研究表明如果你的皮肤白净那么强烈的阳光会使得叶酸等级减半。Jablonski发现这个关系仅用了几周的时间。在胚胎开发的高级阶段,Jablonski了解到过低的叶酸水准与神经管损伤相关,比如脊柱裂或先天无脑畸形(婴儿生来就没有健全的大脑和脊柱)。
Jablonski随后通过三篇文献得知孩子的神经管损伤与它的母亲孕期暴露于紫外线下密切相关。而且她发现叶酸与精液水平密切相关——通过抑制叶酸可以起到避孕作用。(Jablonski说:叶酸无处不在,它几乎影响我们的全身上下)。她现在发现了一些有趣的证明:叶酸让会我们慢慢进化出黑色皮肤,但是为什么有人皮肤却很白呢。
追溯到1960年,生物学家W.FarsworthLooms曾发表说肤色与人体的维生素D水平相关。而维他命D可以帮助人体吸收钙质构成坚硬的骨骼,尤其是快速发育的胚胎。(孕期需要很多的维生素D,这也就解释了为什么从世界范围来看女性的皮肤要比男性白皙。)不同于叶酸,维生素D需要紫外线的配合以发挥作用。Loomis坚信生活在北方的人由于那里光线较弱所以他们的皮肤较为白以便吸收更多的紫外线;而生活在热带地区的人们则长有黑色皮肤以便阻挡阳光,使得身体吸收较为均衡的维生素D不至于过量(过量的维生素D会有毒性)。
由于Jablonski的研究Loomis的部分研究成果已经被证明是错误的。Jablonski说:你可以永远不乏获得过量维生素D,因为只有极少数的人们会发生鱼肝油过量。但是Loomis对于皮肤白皙的论点是正确的,这个论点完美的证明了Jablonski对于叶酸和黑色皮肤的论点。接下的任务就是找到数据说明肤色与光线强度的关系。
到80年代,研究人员只能估算紫外线到达地球表面的量,但是在1978年的时候NASA启动了全球臭氧光谱绘制计划。三年后,Jablonski和Chaplin利用全球紫外线光谱数据,并且拿这些数据与他们统计的50个国家和地区的人们肤色进行对比。令他们兴奋不已的是,他们提出的结论完全正确:紫外线越弱,人们的肤色越白皙。Jablonski之后又统计了50个不同地区的严重缺少维生素D的人群。Jablonski说:这个人类历史解决维生素D缺乏是在他们学会钓鱼后,因此他们可以获得更加丰富的实物后,维生素D的问题就已经解决了。
人类的历史中绝大多数时间用来不停地移动,因为这样他们在面对各种环境中才学会了使用工具,制作衣服,解决居住问题并且产生了自己的饮食习惯。但是Jablonski的论点指出我们的适应力非常强。热带的人们拥有黑色皮色以便他们阻挡紫外线以便他们保护自己的叶酸水平。而远离赤道的人们在漫长的冬季中,长出了白皙的皮肤以便产生足够的维生素D。
Jablonski希望她的研究可以改善人们饮食中的维生素D和叶酸的摄入量。比如,总所周知黑色皮肤的人去阴雨地带生活会产生像佝偻病等这样由于缺少维生素D而产生的症状。更重要的是,Jablonski希望人们可以通过她的研究改变会不同肤色的人们的看法。Jablonski说:我们应该将这个理论传播到热带地区,让人们去了解它,用它去解决分歧、误解等等,它完全有这个能力.
Unit 3 Can Dirt Do A Little Good?不干不净 孩子没病?
正如最近一部电影《阳光宝贝》(Babies)所展现的,世界各地的宝宝都如此可爱迷人,但他们所处的卫生条件却各不相同。 影片追随四个身处不同地方的婴儿在这个世界上第一个年头里的生命历程。彭力交(Ponijao)出生在纳米比亚(Namibia)一个游牧民族家庭,从小喝
Infants are enchanting all over the world, as the new movie Babies shows. But their standards of hygiene sure vary.
如最近一部电影《阳光宝贝》(Babies)所展现的,世界各地的宝宝都如此可爱迷人,但他们所处的卫生条件却各不相同。
The film captures the first year of life for four diverse babies. In a nomadic family in Namibia, Ponijao drinks from muddy streams, chews on dry bones and uses her many siblings body parts as toys.
影片追随四个身处不同地方的婴儿在这个世界上第一个年头里的生命历程。彭力交(Ponijao)出生在纳米比亚(Namibia)一个游牧民族家庭,从小喝脏水,啃干骨头,和她的许许多多个兄弟姐妹们扭打,作为自己的玩耍方式。
On a small family farm in Mongolia, a rooster struts around little Bayars bed, a goat drinks from his bathwater and livestock serve as babysitters.
在蒙古国一个家庭小农场里,一只大公鸡在小小的巴亚尔(Bayar)的床边来回踱步,一只山羊过来喝他的洗澡水,周围的家畜就是照料他的保姆。
By contrast, Mari, growing up in high-rise, high-tech Tokyo, and Hattie, whose doting parents live a green lifestyle in San Francisco, both have modern conveniences and sanitation.
与此形成鲜明对比的是,玛丽(Mari)出生在高楼林立的科技之城东京,海蒂(Hattie) 的父母将其视为掌上明珠,在旧金山过着“绿色”的生活方式,两个孩子都享受着便捷的现代生活和干净的卫生环境。
Statistically, Mari and Hattie are healthier. Some 42 out of 1,000 children in Namibia, and 41 out of 1,000 in Mongolia die before their 5th birthday; compared with only 8 in 1,000 in the U.S. and only 4 in Japan.
数据显示,玛丽和海蒂的身体更健康。在纳米比亚,每1000个孩子中约有42个在过五岁生日前夭折,蒙古为41个;而在美国和日本,这一数字仅为8个和4个。
Yet the upscale urban infants are at higher risk for some health problems -- including allergies, asthma and autoimmune diseases like Type 1 diabetes, multiple sclerosis and inflammatory bowel disease -- than the babies in the rural developing world.
不过,城市里的宝宝虽然生活条件优越,但与欠发达国家农村地区的宝宝相比,患上某些疾病的风险更高,包括过敏症、哮喘,以及1型糖尿病、多发性硬化和炎症性肠病等自身免疫性疾病。
While the film makes no mention of hygiene in any of the countries, its images evoke an intriguing medical controversy: Are we too clean, with our preoccupation for hand-sanitizers, disinfectants and anti-microbial products? Now, theres research that suggests there may be a way to get the best of both worlds.
虽然《阳光宝贝》所表达的主旨并非任何一个国家的卫生状况,但片中很多画面引发了一场医学方面的有趣争论。对我们这些非常看重消毒剂、杀菌剂和抗菌产品的城市人来说,到底有没有必要让自己的生活环境太干净?现在,有一项研究认为,也许有一种方法可以拉近两个世界的距离,让彼此取长补短。
According to the hygiene hypothesis, first proposed in 1989, exposure to a variety of bacteria, viruses and parasitic worms early in life helps prime a childs immune system, much like sensory experiences program his brain. Without such early instruction, the immune system may go haywire and overreact with allergies to foods, pollen and pet dander or turn on the bodys own tissue, setting off autoimmune disorders.
根据1989年首次提出的“卫生假说”(hygiene hypothesis)理论,孩子在成长早期如果接触多种病毒、细菌和寄生虫,将有利于其免疫系统的发展,似乎这样能促进大脑对其做出更好的防御准备。反之,如果缺乏这类早期接触,免疫系统就可能出现紊乱,做出过激反应,如对食物、花粉和宠物毛屑过敏等,或者引发人体机理问题,出现自身免疫失调。
Many of these microorganisms evolved symbiotically with humans over millions of years -- the so-called old friends theory. But where theyve been eradicated, a key part of human development has been thrown off. 数百万年以来,许多微生物与人类形成一种共生共栖的关系,就像我们的“老朋友”一样;如果我们将某种微生物连根拔除,就等于错过了人体进化历程中的一个关键环节。
The vast majority of microbes are harmless. There are only a few dozen that can cause lethal infections, says Thomas McDade, director of the Laboratory for Human Biology Research at Northwestern University.
“绝大多数微生物都是无害的,只有几十种微生物会引发致命感染。”美国西北大学(Northwestern University)人体生物研究实验室(Laboratory for Human Biology Research)主任麦克戴德(Thomas McDade)说道。
In 1998, about 1 in 5 children in industrialized countries suffered from allergic diseases such as asthma, allergies and rashes, according to the International Study of Asthma and Allergies in Childhood, a global research initiative. The incidence of peanut allergy in the U.S. tripled between 1997 and , according to a report from Mount Sinai School of Medicine in New York.
“国际儿童哮喘及过敏研究”(International Study of Asthma and Allergies in Childhood)是一项全球性的调查,其数据显示,1998年在发达国家中,只有约20%的孩子患有哮喘、过敏和疹子等过敏性疾病。纽约西奈山医学院(Mount Sinai School of Medicine)的一个报告称,从1997年到,美国的花生过敏症发病率增长了两倍。
But such diseases are still relatively rare in Africa and rural Asia, as are Type 1 diabetes and multiple sclerosis.
然而,上述疾病在非洲和亚洲农村地区依然相对罕见,1型糖尿病和多发性硬化也是如此。
The geographical distribution of allergic and autoimmune diseases is a mirror image of the geographical distribution of various infections diseases, says a report by French researchers in a March issue of the journal Clinical & Experimental Immunology devoted to the hygiene hypothesis.
“过敏症和自身免疫性疾病的地域分布与各类感染性疾病的地域分布恰恰相反。”一位法国研究人员在今年3月《临床与实验免疫学杂志》(Clinical & Experimental Immunology)上发表的一篇文章中说道。该杂志专门研究“卫生假说”理论。
Exposure to immune-stimulating germs may also lower the risk of heart disease, according to Dr. McDade. In a study of 1,700 Filipinos followed from birth to age 21 published this year in the journal Proceedings of the Royal Society, those who grew up around chicken, pigs and dogs and had bouts of diarrhea in childhood had lower rates of C-reactive protein, an inflammation marker that has been linked to cardiovascular disease, as young adults.
麦克戴德称,接触那些能刺激免疫机能的微生物还可能有助于降低心脏疾病的发病率。,英国《皇家学会学报》(Proceedings of the Royal Society)发表了一个报告:一项对1700名菲律宾人从出生到21岁的长期调查显示,那些从小在有鸡鸭猪狗的生活环境中长大、小时候得过几次痢疾的人,成年后体内C反应蛋白的浓度较低。C反应蛋白是一种炎症标志物,与心血管疾病有一定的关联。
There are other dangers lurking in muddy water and animal feces. Nearly 70% of the 8.8 million deaths of children under age 5 world-wide in were caused by infectious diseases, most frequently pneumonia, diarrhea and malaria, according to an analysis in the Lancet last week.
但脏水和动物排泄物也潜藏着其他一些危险。英国医学杂志《柳叶刀》(Lancet)五月中旬发表的一篇分析报告称,在全球880万5岁前夭折的孩子中,有近70%死于感染性疾病,最常见的是肺炎、痢疾和疟疾。
Even though rural Africa and Asia have made enormous strides in public health in the past decade, infant mortality stands at 31 per 1,000 in Namibia and 34 per 1,000 in Mongolia, compared to 7 per 1,000 in the U.S. and 3 per 1,000 in Japan.
虽然过去来非洲和亚洲的农村地区在公共卫生方面有了巨大进步,但纳米比亚的婴儿死亡率仍高达千分之31,蒙古为千分之34,而美国和日本的婴儿死亡率仅为千分之七和千分之三。
Scientists are still working on ways to separate good germs from bad ones; in the meantime, they have a few insights: Studies have shown that children who grow up with household pets have fewer allergies and less asthma than those who don . 科学家仍在寻找办法把好的微生物与坏的微生物区分开来,在此过程中,他们有了几点深入发现。研究表明,从小和家庭宠物一起长大的孩子患过敏症和哮喘病的几率较低。
Michael Bell, an infectious disease specialist and deputy director of Healthcare Quality Promotion at the Centers for Disease Control and Prevention, says that people should be vigilant about wound care since bacteria can cause problems if they get into the blood stream, and he still advocates hand-washing. If you e not doing it 10 times a day, you e probably not doing it enough, he says. But he and other experts say that regular soap and water are fine in most cases. Sterilizing hands is critical mainly for health-care workers and in hospitals, where disease-causing germs are prevalent and can easily spread.
美国疾病控制与预防中心(Centers for Disease Control and Prevention)医疗质量改进部(Healthcare Quality Promotion)副主任及感染病专家贝尔(Michael Bell)说,人们应该警惕伤口感染,因为一旦病毒侵入血液,就会造成各种问题。他还是提倡人们勤洗手。“一天至少要洗10次手。”贝尔说。不过,他和其他一些专家表示,在大多数情况下,洗手用普通的肥皂和水就行了。手部消毒主要适用于医疗工作者以及医院场所内,因为医院里的致病微生物较多,而且容易传播开来。
Many experts advise common sense. We don want to say to children, OK, play by the dirty river bank and catch whatever you can,\ says Dr. Weinstock. But we can say theres nothing wrong with kids playing in the dirt. They don have to live in total sanitation, and they won die from eating something off the floor. Its probably more healthy than not.
许多专家建议人们凭常识办事。“我们不会对孩子们说:‘好,去肮脏的河边玩吧,想抓什么就抓什么。’”温斯托克(Weinstock)医生说,“但可以这样讲,小孩子玩泥巴没什么大不了的,他们不必生活在完全干净的环境中,也不会因为吃掉到地上的东西就死掉。这样说不定会使他们更健康。”
Unit 4 Is Time Travel Possible?
Hello. My name is Stephen Hawking. Physicist, cosmologist and something of a dreamer. Although I cannot move and I have to speak through a computer, in my mind I am free. Free to explore the universe and ask the big questions, such as: is time travel possible? Can we open a portal to the past or find a shortcut to the future? Can we ultimately use the laws of nature to become masters of time itself?
大家好,我是斯蒂芬-霍金,是物理学家、宇宙学家及梦想家,尽管身体不能活动,只能通过电脑与大家交流,但从内心中我是自由的,自由地探索宇宙,思考以下重大问题:时间旅行是否可行?能否打开一个回到过去的通道,或找到通向未来的捷径?我们最终能否利用自然规律成为掌控时间的主人?
To see how this might be possible, we need to look at time as physicists do - at the fourth dimension. Its not as hard as it sounds. Every attentive schoolchild knows that all physical objects, even me in my chair, exist in three dimensions. Everything has a width and a height and a length.
为了让这一切从虚幻变成现实,我们应以物理学家的角度来重新审视时间——即第四维。这个问题没有听上去那么晦涩难懂。每个好学的孩子都知道,任何物体都以三维形式存在,包括坐在轮椅上的我。一切物体都有宽度、高度和长度。
But there is another kind of length, a length in time. While a human may survive for 80 years, the stones at Stonehenge, for instance, have stood around for thousands of years. And the solar system will last for billions of years. Everything has a length in time as well as space. Travelling in time means travelling through this fourth dimension.
此外,还有一种长度——时间的长度。例如,虽然一个人可能活了80岁,但巨石阵的石头却数千年屹立不倒。太阳系的运行将持续数十亿年。一切物体都有时间以及空间的长度。时间旅行意味着我们要经过第四维。
To see what that means, lets imagine we e doing a bit of normal, everyday car travel. Drive in a straight line and you e travelling in one dimension. Turn right or left and you add the second dimension. Drive up or down a twisty mountain road and that adds height, so thats travelling in all three dimensions. But how on Earth do we travel in time? How do we find a path through the fourth dimension?
要想搞明白这一点,我们可以想象正在从事一种日常活动,比如开车。开车沿直线行驶,是在一维中旅行。向左转或是向右转,则是二维旅行。驱车上下山路意味着又多增加了高度,所以是在三维空间内。那么我们怎样才能实现时间旅行?怎样才能发现穿越第四维的通道呢?
Lets indulge in a little science fiction for a moment. Time travel movies often feature a vast, energy-hungry machine. The machine creates a path through the fourth dimension, a tunnel through time. A time traveller, a brave, perhaps foolhardy individual, prepared for who knows what, steps into the time tunnel and emerges who knows when. The concept may be far-fetched, and the reality may be very different from this, but the idea itself is not so crazy.
让我们暂时从科幻电影中寻找答案吧。在此类电影中,通常会有一台巨大而高能耗的时间机器,这台机器产生通往第四维的通道——“时光隧道”。时光旅行者——勇敢但可能有些鲁莽的人,做好我们大家所知道的准备,然后走进时光隧道,来到一个他们想要到达的时间里。这一概念可能有些牵强,事实可能与之存在着天壤之别,但该想法本身不是那么的疯狂。
Physicists have been thinking about tunnels in time too, but we come at it from a different angle. We wonder if portals to the past or the future could ever be possible within the laws of nature. As it turns out, we think they are. Whats more, weve even given them a name: wormholes. The truth is that wormholes are all around us, only they e too small to see. Wormholes are very tiny. They occur in nooks and crannies in space and time. You might find it a tough concept, but stay with me.
物理学家们也在思考时光隧道,但我们的角度不同。我们想搞清过去或未来的通道是否存在于自然规律中?事实证明,我们认为确实是这样的。而且,我们还给它们起了一个名字:虫洞。其实,虫洞无处不在,只是因为太小,我们肉眼看不到罢了。虫洞非常小,存在于时空的隐蔽处和缝隙里。你或许认为这是一个难以理解的概念,请耐心听我继续解释吧。
Nothing is flat or solid. If you look closely enough at anything youll find holes and wrinkles in it. Its a basic physical principle, and it even applies to time. Even something as smooth as a pool ball has tiny crevices, wrinkles and voids. Now its easy to show that this is true in the first three dimensions. But trust me, its also true of the fourth dimension. There are tiny crevices, wrinkles and voids in time. Down at the smallest of scales, smaller even than molecules, smaller than atoms, we get to a place called the quantum foam. This is where wormholes exist. Tiny tunnels or shortcuts through space and time constantly form, disappear, and reform within this quantum world. And they actually link two separate places and two different times.
任何物质都不是平整无暇和实心的,如果仔细观察,会发现它们上面都存在小孔和裂缝,这是一个基本的物理原理,同样适用于时间。即便是像台球一样的东西,上面也有裂缝、褶皱或空洞。现在容易说明这种情况也存在于第一个三维中。相信我,这一原理同样适用于第四维。时间也存在许多微小的裂缝、褶皱和空洞。在最小的刻度下——比分子甚至原子都小,我们来到一个称为量子泡沫(quantum foam)的地方,这是虫洞存在之处。时空中的微小隧道或捷径不停地在这个量子世界中形成、消失和重新形成。它们可以连接两个隔离的空间以及两个不同的时间。
Unfortunately, these real-life time tunnels are just a billion-trillion-trillionths of a centimetre across. Way too small for a human to pass through - but heres where the notion of wormhole time machines is leading. Some scientists think it may be possible to capture a wormhole and enlarge it many trillions of times to make it big enough for a human or even a spaceship to enter.
不幸的是,现实生活中这种时光隧道非常狭小,即使发现了它们,我们也不能从这个缝隙穿过——可这正是“虫洞时间机器”概念的前进方向。部分科学家认为,或许有一天捕捉到一个虫洞,将它放大数万亿倍,令其足够的大,能让人甚至飞船进入。
Given enough power and advanced technology, perhaps a giant wormhole could even be constructed in space. Im not saying it can be done, but if it could be, it would be a truly remarkable device. One end could be here near Earth, and the other far, far away, near some distant planet.
如果我们拥有足够的能量和先进的技术,将来或许甚至能在太空中建造一个巨型虫洞。我并不是说一定可以做到,但如果真的有这种装置,那么确实很了不起。一端在地球的附近,另一端则在遥远的星球附近。从理论上讲,虫洞或时光隧道不仅仅能把我们带到别的星球。一端在地球的附近,另一端则在遥远的星球附近。
Theoretically, a time tunnel or wormhole could do even more than take us to other planets. If both ends were in the same place, and separated by time instead of distance, a ship could fly in and come out still near Earth, but in the distant past. Maybe dinosaurs would witness the ship coming in for a landing.
从理论上讲,虫洞或时光隧道不仅仅能把我们带到别的星球。如果两端在同一个地方,且由时间而非距离分离,在遥远的过去,飞船就能在地球附近自由出入。或许恐龙会看到飞船登陆的场景。
The fastest manned vehicle in history was Apollo 10. It reached 25,000mph. But to travel in time well have to go more than 2,000 times faster.
在人类历史上,速度最快的载人飞船“阿波罗”10号,速度为每小时2.5万英里(约合每小时4万公里),但要实现在时间中旅行,我们的速度必须是“阿波罗”10号速度的2000倍。
Now, I realize that thinking in four dimensions is not easy, and that wormholes are a tricky concept to wrap your head around, but hang in there. 如今,我意识到以四维方式思考并不容易,虫洞是一个令你绞尽脑汁的概念。
A well-known problem with time travel to the past, the problem of what we call paradoxes. Paradoxes are fun to think about. The most famous one is usually called the Grandfather paradox. I have a new, simpler version I call the Mad Scientist paradox.
一个原因可能是回到过去的时间旅行所存在的问题——我们称之为悖论,一个众所周知的问题。探讨悖论是一件很有趣的事情,最著名的悖论通常被称为“祖父悖论”。我有一个新的简化版本——“疯狂科学家”悖论。
I don like the way scientists in movies are often described as mad, but in this case, its true. This chap is determined to create a paradox, even if it costs him his life. Imagine, somehow, hes built a wormhole, a time tunnel that stretches just one minute into the past.
我不喜欢一些电影中科学家被描述成疯狂的群体,但在这种情况下,确实如此。这个家伙决心建立一个悖论,即便付出生命代价在所不惜。可以想见,他是在建造虫洞——仅需一分钟就来到过去的时光隧道。通过虫洞,这位科学家可以看到他一分钟以前的自我。
Through the wormhole, the scientist can see himself as he was one minute ago. But what if our scientist uses the wormhole to shoot his earlier self? Hes now dead. So who fired the shot? Its a paradox. It just doesn make sense. Its the sort of situation that gives cosmologists nightmares.
如果这位科学家利用虫洞向以前的自我开枪,会发生什么事情?他现在已经一命呜呼。那又是谁开的枪呢?这便是一个悖论,听上去毫无意义。但这却是那种让宇宙学家做噩梦的状况。
This kind of time machine would violate a fundamental rule that governs the entire universe - that causes happen before effects, and never the other way around. I believe things can make themselves impossible. If they could then thered be nothing to stop the whole universe from descending into chaos. So I think something will always happen that prevents the paradox. Somehow there must be a reason why our scientist will never find himself in a situation where he could shoot himself. And in this case, Im sorry to say, the wormhole itself is the problem.
这种时间机器会违反整个宇宙所遵循的基本规则。我认为一切皆有可能。如果真是如此,那么就没有任何办法阻止整个宇宙陷入混乱。所以,我认为有些事情总会发生以阻止这种悖论。在某种程度上,这或许是科学家永远不会发现他面临向自己开枪境地的原因。在这种情况下,我只能遗憾地告诉大家,虫洞本身就是一个问题。
In the end, I think a wormhole like this one can exist. And the reason for that is feedback. If youve ever been to a rock gig, youll probably recognise this screeching noise. Its feedback. What causes it is simple. Sound enters the microphone. Its transmitted along the wires, made louder by the amplifier, and comes out at the speakers. But if too much of the sound from the speakers goes back into the mic it goes around and around in a loop getting louder each time. If no one stops it, feedback can destroy the sound system.
最后,我认为像这样的虫洞不能存在,原因就是反馈。如果你有到摇滚演唱会现场观看演出的经历,你可能会辨别出这种尖利的噪音。这就是反馈,引起反馈的原因很简单。声音进入麦克风,通过电线传播,经由扩音器令声音放大,在一个环状物内绕来绕去,每次令声音比上一次更大。如果没人阻止,反馈能够破坏音响系统。
The same thing will happen with a wormhole, only with radiation instead of sound. As soon as the wormhole expands, natural radiation will enter it, and end up in a loop. The feedback will become so strong it destroys the wormhole. So although tiny wormholes do exist, and it may be possible to inflate one some day, it won last long enough to be of use as a time machine.
虫洞也会遇到这种问题,只不过声音换成了辐射。一旦虫洞变大,大自然的辐射物会进入,最终形成一个环路。反馈变得如此强劲,最终摧毁虫洞。虽然微型虫洞确实存在,也有可能在某一天不断膨胀,但持续时间不会太长久,所以不能当作时间机器使用。
Any kind of time travel to the past through wormholes or any other method is probably impossible, otherwise paradoxes would occur. So sadly, it looks like time travel to the past is never going to happen. A disappointment for dinosaur hunters and a relief for historians.
任何通过虫洞和其他方式回到过去的时间旅行或许都是不可能的,否则,悖论就会出现.因此,遗憾的是,回到过去的时间旅行应该永远不会上演。对于寻找恐龙的人来说,这会令他们大失所望,但对于历史学家而言,他们可以彻底解脱了。
Unit 5 The end of e-mail age
Email has had a good run as king of communications. But its reign is over.
电子邮件作为通信之王经历了飞速发展。不过它的统治时代已经终结。
In its place, a new generation of services is starting to take hold -- services like Twitter and Facebook and countless others vying for a piece of the new world. And just as email did more than a decade ago, this shift promises to profoundly rewrite the way we communicate -- in ways we can only begin to imagine.
新一代服务开始取而代之,比如Twitter、Facebook和其他无数争着想在新世界中分一杯羹的服务。如同10多年前电子邮件的出现一样,这一转变有望深刻地改写人们通信的方式──以我们刚刚能够开始想像得到的方式。
We all still use email, of course. But email was better suited to the way we used to use the Internet -- logging off and on, checking our messages in bursts. Now, we are always connected, whether we are sitting at a desk or on a mobile phone. The always-on connection, in turn, has created a host of new ways to communicate that are much faster than email, and more fun.
当然,我们仍会使用电子邮件。不过电子邮件更适合以往人们使用互联网的方式──隔三差五地登录、登出、查看信息。如今,我们总是联着网,无论我们是坐在桌子前还是用手机。这种总是联网的状态产生了一系列新的通信方式,比电子邮件要快的多,也有趣的多。
Why wait for a response to an email when you get a quicker answer over instant messaging? Thanks to Facebook, some questions can be answered without asking them. You don need to ask a friend whether she has left work, if she has updated her public status on the site telling the world so. Email, stuck in the era of attachments, seems boring compared to services like Google Wave, currently in test phase, which allows users to share photos by dragging and dropping them from a desktop into a Wave, and to enter comments in near real time.
如果你可以通过及时消息更快地得到答案,为什么还要等待电子邮件回复呢?由于Facebook的出现,有些问题不必问就已经知道答案了。如果一位朋友更新了Facebook上的公开状态,告诉全世界她已经下班了,你就无需再问她了。与目前处于测试阶段的谷歌Wave等服务相比,拖着“附件”的电子邮件看起来要枯燥得多。通过谷歌Wave,用户可以把照片从桌面拖放到Wave中,与别人分享照片,并输入评论。
Little wonder that while email continues to grow, other types of communication services are growing far faster. In August , 276.9 million people used email across the U.S., several European countries, Australia and Brazil, according to Nielsen Co., up 21% from 229.2 million in August . But the number of users on social-networking and other community sites jumped 31% to 301.5 million people.
难怪在电子邮件继续增长之际,其他类型的通信服务却在以更高的速度增长。据尼尔森(Nielsen Co.)的数据,8月,美国、欧洲的几个国家、澳大利亚和巴西有2.769亿电子邮件用户,较8月的2.292亿增长了21%。而社交网站和其他社群网站的用户数量飙升了31%,至3.015亿。
So, how will these new tools change the way we communicate? Lets start with the most obvious: They make our interactions that much faster.
那么,这些新的工具将如何改变我们通信的方式?让我们先看看最一目了然的方面:它们使我们的交流互动更快了。
Years ago, we were frustrated if it took a few days for a letter to arrive. A couple of years ago, wed complain about a half-hour delay in getting an email. Today, we gripe about it taking an extra few seconds for a text message to go through. In a few months, we may be complaining that our cellphones aren automatically able to send messages to friends within a certain distance, letting them know we e nearby. (A number of services already do this.)
很多年前,如果信件要几天才能到达,我们会感到沮丧不已。几年前,如果电子邮件接收迟了半小时,我们就会抱怨连连。而今天,如果一条文字信息的传送多花了几秒钟的时间,我们就会发牢骚。几个月后,我们可能会抱怨自己的手机不能自动地向一定距离内的朋友发短信,让他们知道我们就在附近。(已经有很多服务提供这样的功能了。)
These new services also make communicating more frequent and informal -- more like a blog comment or a throwaway aside, rather than a crafted email sent to one person. No need to spend time writing a long email to your half-dozen closest friends about how your vacation went. Now those friends, if they e interested, can watch it unfold in real time online. Instead of sending a few emails a week to a handful of friends, you can send dozens of messages a day to hundreds of people who know you, or just barely do.
这些新的服务还会使通信更频繁和随意──更像是博客评论或随便说出的话,而不是发给一个人的精雕细琢的电子邮件。无需花费时间给你那几个最好的朋友写长长的电子邮件,谈论你的假期过的如何。如今,如果这些朋友感兴趣的话,他们可以实时地在网上了解你的度假生活。你不是每周向屈指可数的几个朋友发送几封电子邮件,而是可以每天向数百个认识你或和你半生不熟的人发送几十条消息。
Consider Twitter. The service allows users to send 140-character messages to people who have subscribed to see them, called followers. So instead of sending an email to friends announcing that you just got a new job, you can just tweet it for all the people who have chosen to follow you to see. You can create links to particular users in messages by entering @ followed by their user name or send private direct messages through the system by typing d and the user name.
你可以考虑用Twitter。这个服务使用户可以向注册阅读用户(即关注者,followers)发送140个字符的信息。因此,你不用向朋友发封电子邮件,宣布你刚刚找到了一份新工作,你只要向所有选择“关注(follow)”的人“推(tweet)”一下就可以了。你可以在信息中创建特殊用户链接,只要输入@再加上他们的用户名,也可以通过输入“d”加用户名通过系统发送私人“直接消息”。
Facebook is part of the trend, too. Users post status updates that show up in their friends streams. They can also post links to content and comment on it. No in-box required.
Facebook也是这一趋势的一部分。用户可以更新状态,显示在朋友的“流”中。他们还可以发内容链接、对其进行评论。无需收件箱。
Dozens of other companies, from AOL and Yahoo Inc. to start-ups like Yammer Inc., are building products based on the same theme.
其他几十个企业都开始建立基于同样主题的产品,包括美国在线(AOL)、雅虎(Yahoo)和Yammer这样的初创企业。
David Liu, an executive at AOL, calls it replacing the in-box with a river that continues to flow as you dip into it.
美国在线的一位高管David Liu说,收件箱的替代品好像是“在你踏入其中,一条仍继续流淌的河”。
But the speed and ease of communication cut both ways. While making communication more frequent, they can also make it less personal and intimate. Communicating is becoming so easy that the recipient knows how little time and thought was required of the sender. Yes, your half-dozen closest friends can read your vacation updates. But so can your 500 other friends. And if you know all these people are reading your updates, you might say a lot less than you would otherwise.
不过,通信的速度和舒适性也是双刃剑。尽管可以使通信变得更频繁,却也可能使它变得更缺乏私密性。通信开始变得如此简单,收件人知道发件人只需很少的时间和思考。不错,你那几个最好的朋友可以阅读你的度假情况。不过你的其他500个“朋友”也可以。如果你知道所有这些人都在阅读你的更新,你可能就不会说那么多了。
Another obvious downside to the constant stream: Its a constant stream.
持续不断流动的信息有着另外一个显而易见的不利因素:它是持续不断的
That can make it harder to determine the importance of various messages. When people can more easily fire off all sorts of messages -- from updates about their breakfast to questions about the evenings plans -- being able to figure out which messages are truly important, or even which warrant a response, can be difficult. Information overload can lead some people to tune out messages altogether.
这可能会加大判断各种信息重要性的难度。当人们可以更容易地发送从早餐到夜生活计划的各种各样的信息时,能够判断出哪些信息是确实重要的,或哪些需要回复,都不是轻而易举的事。过量的信息可能会导致一些人干脆对全部信息都置之不理。
Such noise makes us even more dependent on technology to help us communicate.Without software to help filter and organize based on factors we deem relevant, wed drown in the deluge.
这样的“噪声”使我们更加依赖于技术来帮助交流。如果没有软件帮助我们根据我们认为相关的因素对信息进行过滤和组织,我们就会淹没在海量的信息中。
Perhaps the biggest change that these email successors bring is more of a public profile for users. In the email world, you are your name followed by a dot-com. Thats it. In the new messaging world, you have a higher profile, packed with data you want to share and possibly some you don .
或许电子邮件的这些接班人带来的最大变化是用户的公开信息增多。在电子邮件的世界里,你就是你的名字加上“.com”。仅此而已。在新的通信世界里,你的个人信息增多了,充满你希望与人分享的数据,可能还有一些你不希望与人分享的信息。
Such a public profile has its pluses and minuses. It can draw the people communicating closer, allowing them to exchange not only text but also all sorts of personal information, even facial cues. You know a lot about the person you are talking to, even before youve ever exchanged a single word.
这样的公开信息有利也有弊。它可以让人们更近地交流,使他们不仅可以交流文字,还有各种各样的个人信息,甚至是面部表情。你会通过互联网非常了解和你对话的人,甚至是在你们真正开口说第一个字之前
Unit 6 Are Cell phone Safe?
While some studies have suggested that frequent use of cell phones causes increased risk of brain and mouth cancers, others have found no such links. But since cell phones are relatively new and brain cancers grow slowly, many experts are now recommending taking steps to reduce exposure.
一些研究显示,经常使用手机会增加得脑部和口腔癌症的几率。有的研究却没发现两者之间有什么联系。但是,手机算是个新兴事物,而脑癌发展也缓慢,许多专家还是建议减少使用手机。
Does your cell phone increase your risk of brain cancer? Does it affect your skin or your sperm viability? Is it safe for pregnant women or children? Should you keep it in your bag, on your belt, in your pants or shirt pocket? Should you use a hands-free headset? Are present cell phone safety standards strict enough?
手机会增加得脑癌的几率吗?会不会影响皮肤或者精子活性?使用手机对孕妇或孩子安全吗?应该把手机放在哪,包里、衣服口袋,还是挂在腰带上?打电话的时候要用耳机吗?现在的手机安全标准够不够严?
You don’t know? You’re not alone.
你不知道?这很正常。
With some 4 to 5 billion cell phones now in use worldwide and hundreds of studies seeking evidence of their health effects published in peer-reviewed journals over the last 10 years, there’s precious little scientific certainty over whether cell phones pose any danger to those using them. For nearly every study that reports an effect, another, just as carefully conducted, finds none. All of which leaves journalists, consumer advocates, regulatory agencies, politicians, industry spokespersons, and cell phone users able to choose and interpret the results they prefer, or ignore the ones they don’t.
如今,全世界共有40-50亿手机正在使用。过去十年里,成百上千的研究也在致力于寻找手机影响健康的证据,并在相关刊物上发表论文。但还没有确凿的证据能证明,使用手机损害健康。几乎没有研究发现手机对健康有不良影响。但这还是没影响到政治家、新闻记者、管理机构、产业发言人、消费者保护团体,还有消费者自己,选择他们喜好的结果去理解,忽略不喜欢的那些。
Do you, for instance, cite the studies that report adverse effects on sperm viability and motility, due to exposure to cell phone radiation or the studies that showed no– or-mixed-results?
例如,您是否引用了报告由于暴露于手机辐射而引起的对精子活力和运动性的不利影响的研究,或者显示无混合结果的研究?
Do you cite the 2001 study that found increased incidence of uveal melanoma (a cancer of the eye) among frequent cell phone users, or the study by the same authors that, in reassessing their data, found no increase?
2001年的研究显示,常用手机的人患葡萄膜黑色素瘤(一种眼内癌症)几率会增大。这些研究员又发表报告称,他们再分析当年的数据时,又不能确定几率是否真会增大。你是否也引用了以上结果呢?
Do you cite the Israeli study that found an association between salivary gland cancer and heavy use of cell phones or the Swedish study that found none?
以色列科学家发现唾液腺癌和经常使用手机有一定联系,瑞典科学家门确没得出这个结论。你是否还引用过这些?
Do you parse the data and report only those results that have found effects — no matter how small — without citing studies that found no effects? In its much-cited review of cell phone studies, the Environmental Working Group has done just that, reporting, for instance, that “a study from the University of California, Los Angeles, found a correlation between prenatal exposure to cell phone radiation and behavioral problems in children.” But the group left out the study’s very next sentence acknowledging that the association may be “noncausal and may be due to unmeasured confounding.”
你是不是只引用发现不良影响的研究报告,不管其影响多么微乎其微?而从来对没发现不良影响的研究视而不见?环境工作小组就在关于手机的报告中引用了许多负面结论,例如:洛杉矶加州大学的一项研究发现胎儿受到手机辐射和长大后的行为问题有关。但这个研究组在下一句中接着又承认这种关系可能“并没有因果关系,而且也许是其他因素共同作用造成的”。
The effects of cell phones have proven difficult to assess because they are relatively new, the way and the amount they’re used continues to evolve, and the problems that cell phones might cause are hard to detect. Brain cancers, for instance, are very rare cancers. They affect only some 18 out of every 100,000 people. But the fact that there’s been no recent increase in the numbers may be meaningless with regard to cell phone use since brain cancers are very slow-growing.
众所周知,手机的影响很难估计。因为手机还是个新鲜事物,人们使用手机的方式和数量也在不断改变,所以这个作用就很难检测。举个例子,脑癌,这是一种很少见的癌症。十万人但中只有18个人可能患脑癌。事实上,最近几年,这个比例并没增长,这说明手机的使用和脑癌并没有因果关系。
Cell phones produce “non-ionizing” radiation, which, unlike X- or gamma rays, doesn’t damage DNA by stripping away electrons from molecules in cell tissue. Radiofrequency energy does, however, produce heat and, at high enough levels, can damage cell tissue. This, in the late 1990s, The question is whether safety standards are sufficient to protect against long-term exposure.prompted the U.S. Federal Communications Commission (FCC) and the International Commission on Non-Ionizing Radiation Protection (ICNIRP) in Europe to set limits on cell phones’ Specific Absorption Rate (SAR) — the measure of the amount of radiofrequency energy a cell phone user absorbs — at, respectively, 1.6 and 2.0 watts per kilogram. The question remains, however, whether these standards are sufficient to protect against long-term exposures and whether the buildup of heat in cell tissues is more damaging where there’s less blood flow to dissipate it, such as the outer ear, brain, skin, or testes.
手机产生“非电离”辐射,它不像X或伽马射线那样从细胞组织中的分子里分理出电子,从而破坏DNA。但高频能量确实产生热量,而且当频率足够高时能破坏细胞组织。以上结论是上世纪九十年代末,由美国联邦通讯委员会(FCC)与欧洲的国际非电离辐射保护委员会(ICNIRP)提出,为了限制手机辐射吸收率(SAR)(即每个手机用户使用电话时吸收的高频能量多少),前者规定最高不能超过1.6瓦特/千克体重,而后者为2.0瓦特/千克体重。这就给我们留下了一些问题:这些标准到底能不能有效保护人们免受长期辐射?是不是当细胞组织(如外耳、大脑、皮肤和睾丸)中血量不够分散热量时,其本身积累的热量破坏性更大?
The exposure standard has been the subject of Congressional hearings. Consumer groups have warned that children may be more susceptible to radiofrequency heating effects than adults. U.S. Congressman Dennis Kucinich introduced a bill for a federal research program on the effects of cell phone radiation that also calls for a label warning users about potential links between long-term use and cancer.
辐射量标准已经成为议会听证会的议题。消费者被告知,儿童比成人更容易受到高频热效应的影响。美国议员Dennis Kucinich提出一项议案,即设立一个联邦项目,研究手机辐射的影响,并号召以后再手机上标示出“长时间使用手机与癌症有潜在关系”之类的标语,警告消费者。
Last month, San Francisco passed a “Cell Phone Right-to-Know” law that requires manufacturers to post in stores each cell phone’s Specific Absorption Rate. In response, CTIA-The Wireless Association, which represents the wireless communications industry, filed suit July 23 in U.S. District Court in San Francisco to block enforcement of the new law. It cites the U.S. Food and Drug Administration’s (FDA) statement that “the weight of scientific evidence has not linked cell phones with any health problems.”
上月,旧金山通过了一项“手机知情权”法律,要求生产商在销售店明确标示每一部手机的辐射吸收率。同时,代表无线通讯产业的美国无线通讯协会,于7月23日在美国地方法院提出反对诉讼,阻止这项新法律的实行。其引用了美国食品与药物管理局(FDA)的报告“现有科学证据不足以证明手机与任何健康问题间存在联系”。
So far, the National Cancer Institute stands by the FDA. And neither the FCC nor the ICNIRP has recommended any changes in their present standards until there’s clear scientific evidence to demonstrate they need changing. 美国国家癌症研究所支持食品与药物管理局的结论。联邦通讯委员会与国际非电离辐射保护委员会也表示,在未有清楚科学依据证明现有标准需要变动前,他们将维持此标准。
That kind of clarity may be a long way off.
不过这些清楚科学证据似乎离我们还很远。
Take, for example, the findings released in May of INTERPHONE, the largest and longest study ever conducted on whether — and by how much — cell phone use increases the odds of developing brain cancer. Carried out by the International Agency for Research on Cancer — at a cost of some $25 million and nearly 10 years in the making — the study involved roughly two dozen scientists and research teams from around the world and some 10,000 patients and cell phone users from 13 countries. The study’s epic scope, however, only made its meager conclusions seem all the more unsatisfying.
以INTERPHONE研究五月份发表的结论为例子。这是目前规模最大持续时间最长的研究,针对手机会不会增大使用者患脑癌的几率,且会在多大程度上影响。由国际癌症研究署(IARC)主持,耗资2500万美元,历时十年。共有世界各国的约24位科学家和研究团队参与,涉及来自13个国家的一万多名患者和手机用户。研究对象范围虽然很广,但结论还是太缺乏说服力。
“Overall, no increase in risk of glioma [a cancer of the cells that protects the brain’s neurons] or meningioma [tumors that develop in the tissue that surrounds the brain] was observed with use of mobile phones,” the study concluded. “The possible effects of long-term heavy use of mobile phones require further investigation.”
研究结论是:“总体来看,手机用户患神经胶质瘤(神经胶质是保护大脑神经的一种细胞)和脑膜瘤(脑膜是大脑周围的组织)的风险不会增加。长时间大量使用手机可能造成的影响,需要进一步研究。”
And yet even these modest claims proved contentious. The study scientists themselves recognized problems in the methodology: While they had good data on the participants’ tumor and cancer histories, they had very suspect ‘After 10 years of research, we do not have an answer whether mobile phone radiation causes brain cancer,’ says one expert.data on their cell phone usage. Participants’ recall of how often and how much they talked on their cell phones, when checked against their actual cell phone records, in some cases proved very unreliable. The matching of patients with control subjects also turned out to be problematic. Should controls include only those who never used a cell phone and exclude those who’d used one only infrequently? While the distinction may seem insignificant, such selection biases can wreak statistical havoc. The analysis using the first group, for instance, resulted in the somewhat astonishing finding that regular users of cell phones had a reduced risk of developing glioma.
但这一谨慎的结论颇具争议。参与的科学家发现了研究方法的缺陷:虽然他们在参与者肿瘤及癌症病史方面的数据比较准确,但对于患者手机使用情况的数据就很难保证了。使用情况方面主要通过病人自己回忆他们打手机的频率和时间长短,但有时在查询他们的手机实际通话记录时,病人的回忆也很不可靠。用来对照研究结果的非手机用户组数据也有问题。这一组是不是应该只研究从来不用手机的人,而把极少用手机的人排除在外呢?虽然这一差别看起来对研究结果影响不大,但实际上这种选择误差会破坏数据的准确性。例如,只选从不用手机的参与者的数据分析,竟然发现经常使用手机的用户患神经胶质瘤的几率低!
No one was surprised, therefore, that divisions appeared over interpreting the study’s results. These delayed its release for four years. The raw data, in fact, showed that “long-term heavy use” — that is, talking on a cell phone for 30 minutes a day for 10 years — increased the odds of developing glioma by 40 percent. The question was whether this result was subject to the same selection bias as that which strangely showed a reduced risk among regular users. The final decision was that the findings with regard to the “effects of long-term heavy use” were, while worth “further investigation,” too unreliable to conclude they represented a clear and irrefutable increased risk.
因此,大家也没感到惊讶,这种分组方法显然过度解释了研究结果。所以,研究结果的发布推迟了整整四年。其实,原数据表明,“长时间大量使用”手机(即每天打电话30分钟以上,保持),将导致神经胶质瘤的发生几率提高40%。但问题是,这一结果是否与之前经常使用手机的用户患病几率降低的结论一致呢?最后他们决定,针对“上时间大量使用的影响”,若下结论说其会增加患病几率则太没说服力,需要“进一步研究”。
Unit 8 Why We e Fat
So why is obesity happening? The obvious, clichéd-but-true answer is that we eat too much high-calorie food and don burn it off with enough exercise. If only we had more willpower, the problem would go away. But it isn that easy.
为什么会有肥胖症?一个明显、老生常谈但又真实的答案就是我们吃太多高热量食物并且没有进行足够的运动消耗它。要是我们的意志力更强大,这个问题便迎刃而解了。但是,问题并不是那么简单。
When warned about the dangers of overeating, we get briefly spooked and try to do better. Then we e offered a plateful of pancakes smothered in maple syrup, our appetite overpowers our reason, and before we know it, we e at it again. Just why is appetite such a powerful driver of behavior, and, more important, how can we tame it?
当我们被警告说吃得太多的时候,一时总会被吓倒并努力做好一些。然后一碟涂满槭糖浆的煎饼摆在面前,我们的食欲战胜了我们的理智,等到我们意识到它的时候,我们又重蹈覆辙了。到底为什么食欲具有如此强大的推动力?更重要的是,我们怎么才能够控制它?
itWhin the past few years, science has linked our ravenous appetites to genes and hormones. Among the hormones that fuel these urges are ghrelin and leptin, known as the "hunger hormones." Ghrelin is produced mostly by cells in the stomach lining. Its job is to make you feel hungry by affecting the hypothalamus, which governs metabolism. Ghrelin levels rise in dieters who lose weight and then try to keep it off. Its almost as if their bodies are trying to regain the lost fat. This is one reason why its hard to lose weight and maintain the loss.
近几年来,科学将我们迫不及待要吃的食欲跟基因和激素联系起来。激起这些强烈的欲望的激素有胃促生长素和消瘦素,也被称作“饥饿激素”。胃促生长素主要由胃保护层的细胞产生。它的职责是影响控制新陈代谢的下丘脑,让你感到饥饿。当节食者减肥并且努力维持减肥效果,他的胃促生长素水平就会升高。就像他们的身体要试图恢复失去的脂肪。这是为什么很难减肥并维持减肥效果的原因之一。
Leptin turns your appetite off and is made by fat cells. Low leptin levels increase your appetite and signal your body to store more fat. High leptin levels relay the opposite signal. Many obese people have developed a resistance to the appetite-suppressing effects of leptin and never feel satisfied, no matter how much they eat. Basically, your body uses these hormones to help you stay at your weight and keep you from losing fat — which is another reason why dieting can be so difficult.
消瘦素消除你的食欲,它来自脂肪细胞。低消瘦素水平增加你的食欲并通知你的身体储存更多的脂肪。高消瘦素水平传递相反的信号。很多肥胖的人已经形成了一种对消瘦素抑制食欲效应的抵抗,不管他们吃多少也从不感到满足。从根本上说,你的身体利用这些激素帮助你保持现在的体重,不让你的脂肪流走——这是节食如此之难的另外一个原因。
Lack of sleep promotes obesity by messing with these hunger hormones. If you skimp on sleep, ghrelin levels rise, making you hungry, and leptin levels dip, which signals a need for calories. During my internship, I was chronically sleep-deprived because I had to be at the hospital and stay up all night every third night. I gained a lot of weight that year; now I know why. Years later, after I gave birth to my son Alex, I put on a lot of pounds, too — twenty pounds left over from the pregnancy, and twenty pounds from being up all night with him. He had colic (fussiness) and never slept more than twenty minutes at a time the first six months of his life. My weight started coming off more easily when I got more sleep.
睡眠缺失促进肥胖,因其干扰了这些饥饿激素。如果你克扣了睡眠时间,胃促生长素水平升高,使你饥饿,并且消瘦素下降,标志着需求热量。在实习期间我长期缺觉,因为每隔三个晚上我得通宵熬夜待在医院里。那年我的体重增加了不少,现在我明白为什么了。在那几年之后,我生了儿子亚力克斯后又增了好多磅——怀孕期间残留的二十磅,还有夜夜无眠陪着他的二十磅。他有急性腹痛且在他生命中的头六个月从未试过连续睡二十分钟以上。当我有了更多睡眠时间,我的体重开始更容易降下来。
Besides ghrelin and leptin, many other hormones play a role in appetite. Scientists have been looking for ways to control all these hunger hormones, but so far nothing usable has panned out.
除了胃促生长素和消瘦素,很多其他的激素对食欲也有影响。科学家一直在寻找控制这些饥饿激素的方法,但是目前还没有成果。
Hunger isn the only reason people eat and eat and eat. Stress, depression, boredom, loneliness, and even joy all come into play. And some of us may just be inclined to gain weight while others are not, due to genetics. Scientists are unclear as to how much of a role genetics plays in how chubby you are, but estimates range from as low as 20 percent to as high as 90 percent. In studies of twins, researchers have found that siblings wind up with similar body weights, whether or not they are raised in different families, and that adopted children are much more likely to grow to the size of their natural parents than their adoptive ones. Scientists speculate that part of the reason so many of us are susceptible to layering on fat is due to the "thrifty gene." Supposedly, its a gene passed down from our prehistoric ancestors who could eat a lot and build up reserves of fat to survive frequent famines. Genetically, this made sense when you didn know if your next meal would be tomorrow or a week from now, but when your next meal is whenever you drive by a fast-food restaurant, thats a problem.
饥饿不是人们不停地吃的唯一原因。压力,抑郁,无聊,孤独,甚至高兴都会起作用。有些人可能就是易于发胖而另一部分人不会,这应归于遗传。科学家不确定遗传在肥胖上面起多大的作用,但是预测它所占比例从最低20%到最高90%。在对双胞胎的研究中,研究人员发现双胞胎兄弟(或姐妹)最终会有相似的体重,不论他们是不是在不同的家庭中长大,而且收养的小孩的体形大小更可能长成和他们亲生父母的一样。科学家推断我们那么多人易于堆积脂肪的部分原因在于“节俭基因”。假设,我们的祖先食量很大,并且可以积聚脂肪来渡过频繁发生的饥荒。从遗传学角度来看,当你不知道下一餐会在明天还是一周以后这的确说得通,但是当你的下一餐就是在随时开车经过的快餐店,那就是一个问题了。
Another cause of obesity, one that really fascinates me, has to do with a virus called the adenovirus-36. It comes from the family of common viruses that causes colds, pneumonia, diarrhea, and pinkeye and is present in 30 percent of obese people and 5 percent of non-obese people. Scientists found that when human stem cells are exposed to adenovirus-36, they turn into fat cells. This discovery is more evidence that our expanding waistlines are due to factors other than weak willpower and, theoretically, could lead to the development of a vaccine to prevent obesity.
肥胖的另一个起因(也是非常令我着迷的一个)就是关于一个称作腺病毒-36的病毒。它来自引起感冒、肺炎、腹泻和红眼的普通病毒家族, 30%肥胖的人感染了这种病毒,而非肥胖的有5%。科学家发现当人类干细胞感染了腺病毒-36,它们就变成脂肪细胞。这个发现更加证明了我们日益加大的腰围应归于薄弱意志力外的其他因素,而且理论上可能促使防止肥胖疫苗的发展。
Often, hard-to-budge weight is a symptom of a hidden medical problem. You could have hypothyroidism (sluggish thyroid function), a condition that slows down your metabolism and makes it tough to lose weight, or Cushings disease, characterized by high levels of the hormone cortisol in the blood. A glut of cortisol triggers weight gain, mostly in the trunk and face. Some women have polycystic ovary syndrome (PCOS), a treatable condition that involves a hormone imbalance. And about 30 percent of people who are obese have bingeeating disorders. Sufferers don just munch on a few potato chips, they inhale the whole bag, and they do this kind of thing habitually. Even certain medications, some of which may be sitting in your medicine cabinet right now, can put on pounds. Common offenders include some antidepressants like Paxil and Zoloft; mood stabilizers; diabetes drugs; blood pressure agents; steroids; antiseizure drugs; certain hormones; and antihistamines.
难以控制的体重往往是隐藏疾病的一个症状。你可能是甲状腺功能减退,它减慢你的新陈代谢,使减肥变得困难;或者是库兴氏病,特点是血液中皮质醇水平过高。过多的皮质醇引发体重增加,特别表现在躯干和脸上。一些女人有多囊卵巢综合征,它包含激素不平衡,是一种可治疗的情况。大约30%肥胖的人都有无节制狂吃失调症。患者不止吃少量薯片,他们一下子吃一整袋,而且他们习惯性地做这类事情。甚至某些药物也能使人增重,有些可能现在就躺在你的医药箱里。常见的祸害包括抗抑郁药如帕罗西汀和左洛复;情绪安定药;糖尿病药物;血压药;类固醇;抗发作药物;某些激素以及抗组胺。
So perhaps there is a medical issue that spells weight trouble, or our genes and hormones may be conspiring to makes us eat more, or maybe we e infected with a virus that makes us fat. Should we throw up our hands and say, "Well, I can do anything about it, so Ill just stay fat"? No, because obesity will affect your health, and it may kill you eventually. You will just have to work a little harder to get your weight under control.
所以,可能有些医疗问题会带来体重上的困扰,或是我们的基因和激素共谋让我们吃更多,或是我们感染了使我们变胖的病毒。那我们是不是应该投降说“那么,我也没有办法,我也只能保持肥胖”?不是的,因为肥胖会影响你的健康,它最终可能会要了你的命。你只有再努力些去控制自己的体重。
Unit 9 The History of UFOs
In popular culture, the term UFO–or unidentified flying object–refers to a suspected alien spacecraft, although its definition encompasses any unexplained aerial phenomena. UFO sightings have been reported throughout recorded history and in various parts of the world, raising questions about life on other planets and whether extraterrestrials have visited Earth. They became a major subject of interest–and the inspiration behind numerous films and books–following the development of rocketry after World War II.
通俗地说,所谓 UFO——或者不明飞行物——指疑似外星人的飞船,不过它的定义也包括无法解释的空中现象。在全世界各地不同时期都有 UFO 目击的报告,引起人们关于外星生命以及地外生命是否访问过地球的争论。在二战后火箭技术的发展下,它们成了人们感兴趣的一大主题——也是数不清的电影和书籍背后的灵感来源。
Flying Saucers
飞碟
The first well-known UFO sighting occurred in 1947, when businessman Kenneth Arnold claimed to see a group of nine high-speed objects near Mount Rainier in Washington while flying his small plane. Arnold estimated the speed of the crescent-shaped objects as several thousand miles per hour and said they moved “like saucers skipping on water.” In the newspaper report that followed, it was mistakenly stated that the objects were saucer-shaped, hence the term flying saucer.
首个著名的飞碟目击事件发生在 1947 年,一个叫 Kenneth Arnold 的商人声称他在华盛顿的雷尼尔山附近玩小型飞机模型时看到了一组 9 个高速移动的物体。Arnold 估计这些月牙形的物体速度达每小时数千英里,还说他们的移动“就像是打水漂”。在后来的新闻中错误地报道成了这些物体是碟形的,于是就有了飞碟这一称呼。
Sightings of unidentified aerial phenomena increased, and in 1948 the U.S. Air Force began an investigation of these reports called Project Sign. The initial opinion of those involved with the project was that the UFOs were most likely sophisticated Soviet aircraft, although some researchers suggested that they might be spacecraft from other worlds, the so-called extraterrestrial hypothesis (ETH). Within a year, Project Sign was succeeded by Project Grudge, which in 1952 was itself replaced by the longest-lived of the official inquiries into UFOs, Project Blue Book, headquartered at Wright-Patterson Air Force Base in Dayton, Ohio. From 1952 to 1969 Project Blue Book compiled reports of more than 12,000 sightings or events, each of which was ultimately classified as (1) “identified” with a known astronomical, atmospheric, or artificial (human-caused) phenomenon or (2) “unidentified.” The latter category, approximately 6 percent of the total, included cases for which there was insufficient information to make an identification with a known phenomenon.
之后不明的空中现象频发,在 1948 年美国空军开始对这些报告进行调查,称为 Sign 计划。这一计划的最初动机是怀疑这些 UFO 很可能是苏联尖端飞行器,虽然有些研究员认为它们可能是来自其他世界的飞船,也就是所谓的外星人假说(ETH)。在一年内,Grudge 计划继承了 Sign 计划,到了 1952 年它又被 UFO 官方研究计划中历时最长的 Blue Book 计划取代,其总部位于俄亥俄州代顿市的 Wright-Patterson 空军基地。在 1952 年至 1969 年间,Blue Book 编辑了一万两千多宗目击事件的报告,每一个最后都标上“已确认”或者“未确认”,“已确认”的包括已知的天文现象、大气现象和人造(人为引起的)现象。后者约占总数的 6%,包括了一些信息不足,无法用已知的现象定性的事件。
The Robertson Panel and the Condon Report
Robertson 小组和 Condon 报告
An American obsession with the UFO phenomenon was under way. In the hot summer of 1952 a provocative series of radar and visual sightings occurred near National Airport in Washington, D.C. Although these events were attributed to temperature inversions in the air over the city, not everyone was convinced by this explanation. Meanwhile, the number of UFO reports had climbed to a record high. This led the Central Intelligence Agency to prompt the U.S. government to establish an expert panel of scientists to investigate the phenomena. The panel was headed by H.P. Robertson, a physicist at the California Institute of Technology in Pasadena, Calif., and included other physicists, an astronomer, and a rocket engineer. The Robertson Panel met for three days in 1953 and interviewed military officers and the head of Project Blue Book. They also reviewed films and photographs of UFOs. Their conclusions were that (1) 90 percent of the sightings could be easily attributed to astronomical and meteorologic phenomena (e.g., bright planets and stars, meteors, auroras, ion clouds) or to such earthly objects as aircraft, balloons, birds, and searchlights, (2) there was no obvious security threat, and (3) there was no evidence to support the ETH. Parts of the panels report were kept classified until 1979, and this long period of secrecy helped fuel suspicions of a government cover-up.
而美国人已经开始对 UFO 现象着迷。在 1952 年炎热的夏天,在华盛顿特区的国家机场附近发生了一系列令人激动的雷达和肉眼观测报告。虽然这些报告被归结于城市上空空气的温度反转现象,并不是所有人都能接受这个解释。同时,UFO 报告的数量攀升到历史最高。这导致了中情局提请美国政府组建一支由科学家组成的专家小组对这一现象进行调查。这个小组由加州帕萨迪纳市的加州理工学院物理学家 H.P. Robertson 领头,有数名物理学家、一名宇航员和一名火箭工程师。Robertson 小组在 1953 年开了 3 天的会议,访问了 Blue Book 计划的负责人和军方官员。他们也复查了 UFO 的胶片和照片。他们得出结论:(1)90% 的目击事件都可以简单归结为天文和气象现象(例如明亮的天体和星星、流星、极光、离子云)或者地球产物,例如飞机、气球、鸟类,和探照灯光;(2)不存在明显的安全威胁;(3)没有支持外星人假说的直接证据。在 1979 年前这个小组的部分记录被分类存档,长时间的保密也给政府掩盖事实的说法起到了火上浇油的作用。
A second committee was set up in 1966 at the request of the Air Force to review the most interesting material gathered by Project Blue Book. Two years later this committee, which made a detailed study of 59 UFO sightings, released its results as Scientific Study of Unidentified Flying Objects—also known as the Condon Report, named for Edward U. Condon, the physicist who headed the investigation. The Condon Report was reviewed by a special committee of the National Academy of Sciences. A total of 37 scientists wrote chapters or parts of chapters for the report, which covered investigations of the 59 UFO sightings in detail. Like the Robertson Panel, the committee concluded that there was no evidence of anything other than commonplace phenomena in the reports and that UFOs did not warrant further investigation. This, together with a decline in sighting activity, led to the dismantling of Project Blue Book in 1969.
在 1966 年,由于空军想要复查 Blue Book 计划中搜集的最有意思的材料而成立了第二支委员会。两年后,这支队伍在对 59 宗 UFO 目击事件作了详细研究后发表了它的结论,《不明飞行物的科学研究》——也被称为 Condon 报告,这是以这次调查的领头人,一个叫 Edward U. Condon 的物理学家命名的。Condon 报告经过了美国国家科学院的一支特殊委员会的审查。多达 37 名科学在在这份详细说明了 59 宗 UFO 目击报告调查的报告中写下了部分章节或段落。和 Robertson 小组一样,这个委员会得出结论说在这些报告中没有任何证据证明存在非正常的现象,继续调查 UFO 毫无意义。这份报告随着目击事件的减少,导致了 1969 年 Blue Book 计划的解散。
Other investigations of UFOs
其他 UFO 调查
Despite the failure of the ETH to make headway with the expert committees, a few scientists and engineers, most notably J. Allen Hynek, an astronomer at Northwestern University in Evanston, Ill., who had been involved with projects Sign, Grudge, and Blue Book, concluded that a small fraction of the most-reliable UFO reports gave definite indications for the presence of extraterrestrial visitors. Hynek founded the Center for UFO Studies (CUFOS), which continues to investigate the phenomenon.
虽然外星人假说在专家委员会那里未能有所进展,一些科学家和工程师,最著名的有埃文斯顿的西北大学的一位天文学家 J. Allen Hynek 和参与了 Sign、Grudge 和 Blue Book 计划的 Ill,认为一小部分较为可信的 UFO 报告给出了地外访问者存在的明显迹象。Hynek 成立了 UFO 研究中心(CUFOS),继续研究这些现象。
Aside from Project Blue Book, the only other official and fairly complete records of UFO sightings were kept in Canada, where they were transferred in 1968 from the Canadian Department of National Defense to the Canadian National Research Council. The Canadian records comprised about 750 sightings. Less-complete records have been maintained in the United Kingdom, Sweden, Denmark, Australia, and Greece. In the United States, CUFOS and the Mutual UFO Network in Bellvue, Colo., continue to log sightings reported by the public.
除了 Blue Book 计划,唯一一个基本完整的官方 UFO 目击记录被保存在加拿大,它们在 1968 年从加拿大国土防御部转移到了加拿大国家研究理事会。加拿大报告包含了 750 宗目击事件。在英国、瑞典、丹麦、澳大利亚和希腊都存有不太完整的记录。在美国,UFO 研究中心和科罗拉多州 Bellvue 的共有 UFO 网络都在继续记录公众的目击记录。
In the Soviet Union, sightings of UFOs were often prompted by tests of secret military rockets. In order to obscure the true nature of the tests, the government sometimes encouraged the publics belief that these rockets might be extraterrestrial craft but eventually decided that the descriptions themselves might give away too much information. UFO sightings in China have been similarly provoked by military activity that is unknown to the public.
在苏联,UFO 目击常常被认为是秘密的军事火箭测试。为了掩盖测试的真相,政府有时会鼓励民众相信那些火箭是地外飞行器,但最后他们认为即使这样描述所泄漏的情报也太多了。在中国的 UFO 目击也被类似地认为是不公开的军事活动。
Possible explanations for UFO sightings and alien abductions
对于 UFO 目击和外星人绑架事件的可能解释
UFO reports have varied widely in reliability, as judged by the number of witnesses, whether the witnesses were independent of each other, the observing conditions (e.g., fog, haze, type of illumination), and the direction of sighting. Typically, witnesses who take the trouble to report a sighting consider the object to be of extraterrestrial origin or possibly a military craft but certainly under intelligent control. This inference is usually based on what is perceived as formation flying by sets of objects, unnatural—often sudden—motions, the lack of sound, changes in brightness or colour, and strange shapes.
根据目击者数量、目击者是否不受他人影响、观测状况(例如大雾、阴霾、照明类型)以及观测方向,UFO 报告的可信度千差万别。通常,不辞辛劳前来报告的目击者认为那些东西是来自地外的,或者可能是超越常识的军事飞机。这些推论通常是建立在观察到的多个物体的飞行队列、不寻常——通常是瞬间——的运动、没有声音、亮度和色彩的变化,以及奇怪的形状之上的。
That the unaided eye plays tricks is well known. A bright light, such as the planet Venus, often appears to move. Astronomical objects can also be disconcerting to drivers, as they seem to “follow” the car. Visual impressions of distance and speed of UFOs are also highly unreliable because they are based on an assumed size and are often made against a blank sky with no background object (clouds, mountains, etc.) to set a maximum distance. Reflections from windows and eyeglasses produce superimposed views, and complex optical systems, such as camera lenses, can turn point sources of light into apparently saucer-shaped phenomena. Such optical illusions and the psychological desire to interpret images are known to account for many visual UFO reports, and at least some sightings are known to be hoaxes. Radar sightings, while in certain respects more reliable, fail to discriminate between artificial objects and meteor trails, ionized gas, rain, or thermal discontinuities in the atmosphere.
我们都知道裸眼会产生一些错觉。一个明亮的光点,例如金星,常常看上去像在移动。天文物体也会让司机神经兮兮,好像它们在“跟着”他们的车一样。对于 UFO 的距离和速度的视觉印象也非常不可靠,因为他们是基于臆想的尺寸,而且常常是在别无一物的天空中出现,没有背景参照物(比如云、山之类)来确定一个最大距离。窗户和眼镜片的反光会造成重叠的影像,而例如相机镜头这样精密的光学系统会将点状光源扩散为看似碟形的现象。这样的光学幻觉和对图像解释的心理愿望被认为是许多 UFO 目击报告的原因,至少有的目击报告最后被发现纯属欺骗。在某种程度上更为可靠的雷达观测无法区别大气中的人造飞船、流星轨迹、电离的空气、雨滴和热断层。
“Contact events,” such as abductions, are often associated with UFOs because they are ascribed to extraterrestrial visitors. However, the credibility of the ETH as an explanation for abductions is disputed by most psychologists who have investigated this phenomenon. They suggest that a common experience known as “sleep paralysis” may be the culprit, as this causes sleepers to experience a temporary immobility and a belief that they are being watched.
“接触事件”,例如绑架,经常和 UFO 关联起来,因为他们被归结为地外访客。但是,外星人假说来解释绑架事件的可靠性在那些调查过这些现象的心理学家中存在争论。他们认为一种叫作“睡眠性麻痹”的常见情况可能是元凶,它会让睡觉的人感到暂时性的束缚,认为他们被监视了。
Unit 10 Video Gamer Can Control Dreams, Study Suggest
Playing video games before bedtime may give people an unusual level of awareness and control in their dreams, LiveScience has learned.
Live Science网站获悉,在睡觉之前玩视频游戏可以让人们有一种不寻常的清醒做梦和控制梦的水平。
That ability to shape the alternate reality of dream worlds might not match mind-bending Hollywood films such as "The Matrix," but it could provide an edge when fighting nightmares or even mental trauma.
尽管这种塑造现实品梦境的能力与让令人费神才能理解的好莱坞电影《黑客帝国》不同,但它还是能为与噩梦和心理创伤斗争的提供一点优势。
Dreams and video games both represent alternate realities, according to Jayne Gackenbach, a psychologist at Grant MacEwan University in Canada. But she pointed out that dreams arise biologically from the human mind, while video games are technologically driven by computers and gaming consoles.
据加拿大Grant MacEwan大学的心理学家Jayne Gackenbach说,梦和视频游戏都代表另一种现实。但是,她指出从生物学上讲梦来自于人的思维,而视频游戏在技术角度上由电脑和游戏终端来驱动的。
"If you e spending hours a day in a virtual reality, if nothing else its practice," said Jayne Gackenbach, a psychologist at Grant MacEwan University in Canada. "Gamers are used to controlling their game environments, so that can translate into dreams."
“如果你每天把数小时花在虚拟现实中,如果没有做别的事情,那么这种情况就发生”Jayne Gackenbach说,“游戏者一直在控制游戏环境,这样就会转移成梦”。
Gackenbach first became interested in video games in the 1990s, when she watched her son repeatedly kiss a new Nintendo gaming console on the way home from a Toys "R" Us. She had previously focused on studying lucid dreams, in which people have awareness of being in a dream.
1990年代Gackenbach第一次开始关心视频游戏,那时候她看着她的儿子从游戏店Toys "R" Us回家的路上不断的亲吻一台新的”任天堂“游戏机。她之前已经在清醒的梦方面有集中研究,在清醒的梦里,人们能认识得到他们在梦里。
The last decade of game-related research has since yielded several surprises, although the findings represent suggestive associations rather than definitive proof, Gackenbach cautioned. She is scheduled to discuss her work as a featured speaker at the Sixth Annual Games for Health Conference in Boston this week.
Gackenbach警告说,过去十年的游戏相关研究已经产生了许多惊喜,尽管这些发现是暗示性的关联,而不是明确的证明。 她计划在本周在波士顿举行的第六届健康大会年会上作为特邀演讲者讨论她的工作。
What dreams may come
会做什么样的梦
Several intriguing parallels between lucid dreams and video games first emerged when Gackenbach examined past research on games. Both lucid dreamers and gamers seemed to have better spatial skills and were less prone to motion sickness.
当Gackenbach检查她先前研究后,第一次提出清醒睡梦和视频游戏之间几个关键的相似之处,清醒做梦的人和游戏玩家人似乎都有更好的空间技能且不容易晕车。
The two groups have also demonstrated a high level of focus or concentration, whether honed through lucidity-training activities, such as meditation, or through hours spent fighting virtual enemies to reach the next level in a game.
无论是在如冥想这种清醒训练活动中还是在为升级而花几小时打游戏里的虚拟敌人时,这两组对象都表现出很高的关注和集中注意力的能力。
That encouraged Gackenbach to survey the dreams of both non-gamers and hardcore gamers, beginning with two studies published in . She had prepared by conducting larger surveys in-class and online to get a sense of where to focus questions.
这极大的鼓舞了Gackenbach去调查非游戏玩家和专家玩家的梦,开始时就发表了两篇文章。通过在班级和网上更大的调查她已经准备好了,知道问题集中在什么地方。
The first study suggested that people who frequently played video games were more likely to report lucid dreams, observer dreams where they viewed themselves from outside their bodies, and dream control that allowed people to actively influence or change their dream worlds – qualities suggestive of watching or controlling the action of a video-game character.
第一个研究表明:经常玩视频游戏的人更可能报告说有清醒的梦境、可以脱离其身体看自己的观察者梦境,以及允许其主动影响或改变其梦境的梦境控制——这也是观看和控制视频游戏中角色行动的能力。
A second study tried to narrow down the uncertainties by examining dreams that participants experienced from the night before, and focused more on gamers. It found that lucid dreams were common, but that the gamers never had dream control over anything beyond their dream selves.
第二个研究试图通过检查参与者之前的梦来缩小前一结论的不确定性,同时更多的关注于游戏玩家。发现清醒梦境很普遍,但是游戏者从来没有控制其梦境本身以外东西的梦。
The gamers also frequently flipped between a first person view from within the body and a third person view of themselves from outside, except never with the calm detachment of a distant witness.
游戏者也经常在居于自己身体的第一人称视角与身体之外的第三人称之间转换,但从未与梦境中远处的见证者有平静的分离。
"The first time we simply asked people how often they had lucid dreams, looking back over their life and making judgment calls," Gackenbach told LiveScience. "Thats open to all kinds of bias, [such as] certain memory biases, self-reported biases."
第一次我简单的问他们多久有一次清醒梦境,他们回顾过去做出一个判断”,Gackenbach向LiveScience说,“这意味着会有各种各样的偏见,像是特定记忆的偏见,自己报告的偏见”。
Gackenbach eventually replicated her findings about lucid dreaming and video games several times with college students as subjects, and refined her methods by controlling for factors such as frequency of recalling dreams.
Gackenbach最终多次以大学学生为研究对象重复了关于清醒梦境和视频游戏的发现,通过控制诸如回忆梦的频率等因素的方法来进行改进。
Mastering the nightmare world
掌控噩梦
Finding awareness and some level of control in gamer dreams was one thing. But Gackenbach also wondered if video games affected nightmares, based on the "threat simulation" theory proposed by Finnish psychologist Antti Revonsuo.
在游戏玩家的梦中寻找清醒意识和一定程度的控制力是一回事,但是Gackenbach也想知道基于芬兰心理学家Antti Rvonsuo提出的“威胁模拟”理论下,视频游戏是否对噩梦产生影响。
Revonsuo suggested that dreams might mimic threatening situations from real life, except in the safe environment of dream world. Such nightmares would help organisms hone their avoidance skills in a protective environment, and ideally prepare organisms for a real-life situation.
Revonsuo认为梦很可能模仿来自真实生活的威胁,在安全梦环境里却并不如此。这样的噩梦将帮助生物在安全环境中磨炼他们的躲避能力,并让生物为真实情况做最好的准备。
To test that theory, Gackenbach conducted a study with 35 males and 63 females, and used independent assessments that coded threat levels in after-dream reports. She found that gamers experienced less or even reversed threat simulation (in which the dreamer became the threatening presence), with fewer aggression dreams overall.
为证明这一理论,Gackenbach在进行了有35男63女的研究,并使用了独立评估,评估在梦醒后报告里为威胁水平进行编码。她发现,游戏玩家经历的威胁模拟(在威胁模拟中,做梦的人变成了威胁者)更少,甚至是相反的,总体上有侵略性的梦也更少。
In other words, a scary nightmare scenario turned into something "fun" for a gamer.
换句话说,可怕的噩梦轩变成了对于玩家“有意思”的事情。
"What happens with gamers is that something inexplicable happens," Gackenbach explained. "They don run away, they turn and fight back. They e more aggressive than the norms."
“玩家身上发生的事情是令人费解的”,Gackenbach解释说,“他们不会逃跑,而是转过来反击。他们比其它人更具侵略性”。
Levels of aggression in gamer dreams also included hyper-violence not unlike that of an R-rated movie, as opposed to a non-gamer PG-13 dream.
玩家梦里的侵略水平也包括与R级电影(译注:美国电影分级R级:限制级,17岁以下必须由父母或者监护陪伴才能观看。该级别的影片包含成人内容,里面有较多的性爱、暴力、吸毒等场面和脏话。)里的不同高暴力,也与非游戏玩家的PG-13(译注:美国电影分级PG-13 级:特别辅导级,13岁以下儿童尤其要有父母陪同观看,一些内容对儿童很不适宜——粗口、毒品及部分性内容)梦不同。
"If you look at the actual overall amount of aggression, gamers have less aggression in dreams," Gackenbach said. "But when they e aggressive, oh boy, they go off the top."
“如果你看侵略的实际总量,游戏玩家梦里的侵略更少”,Gackenbach说,“但是当他们有侵略性的时候,天呐,他们会达到极高的程度。”
No fear
没有恐惧
The gamer dream experience of high aggression levels matched with little or no fear inspired Gackenbach to pursue a new study with Athabasca University in Canada. If gaming can act as a semi-protective function against nightmares, she reasoned, maybe it could help war veterans who experience post-traumatic stress disorder (PTSD) after enduring combat.
游戏玩家高侵略水平梦里面恐惧微小或者没有恐惧的经验启发了Gackenbach在加拿大Athabasca大学进行一个新的研究。她推理,如果玩游戏可以作为防止噩梦的半保护机能,也许玩游戏可以帮助在长期战争后承受“创伤后应激障碍”(post-traumatic stress disorder (PTSD))痛苦的的老兵。
"I don think anyone has looked at whether theres been a protective function," Gackenbach said. "It makes a lot of sense, but its a hypothesis."
“我认为大家还没看到是不是有保护功能”,Gackenbach说,“尽管感觉上是,但那也只是假设”。
Psychologists consider nightmares as one of the symptoms of PTSD, and studies have shown incredibly high rates of nightmares ranging from 71 to 96 percent among PTSD patients. By contrast, just 3 to 5 percent of civilians reported the same levels of nightmares.
心理学家把噩梦看成是PTSD的症状之一,且研究表明在PTSD病人中有极高的噩梦率,从71%到96%。相反的是,在平民中有相同噩梦水平的仅有3%到5%。
Virtual reality simulators have already been used to help PTSD patients gradually adjust to the threatening situations that plague their waking and sleeping thoughts. If Gackenbachs hunch is correct, perhaps video games could also help relieve the need for nightmares.
虚拟现实模拟器已经用于帮助PTSD病人逐步适应受威胁的状态,那些状况困扰着他们清醒和睡眠时的思绪。如果Gackenbach的直觉是对的,也许视频游戏也可以帮助减少做噩梦。
Finding the balance
寻找平衡点
Gackenbach hopes to someday get a sleep lab and perhaps a virtual reality lab to verify her results, even if studies about video games and dreams have not proven the highest priority for receiving funds. Yet studying video games has attracted more interest and respect from colleagues than studying just dreams alone, she has noticed.
Gackenbach希望有一天搞一个睡眠实验室或者一个虚拟现实实验室来验证她的结果,尽管关于视频游戏和梦的研究还未证明其在接受基金资助上的的最高优先性。但她注意到,视频游戏的研究比单独研究梦吸引了更多同事的兴趣和尊重。
Some of Gackenbachs latest work includes studying the violence levels in games, based upon the video game ratings given out by the Entertainment Software Rating Board, and seeing what effect they have upon aggression within dreams.
Gackenbach最新的一些工作包括,根据“娱乐软件分级委员会”给出的视频游戏分级来研究梦里的暴力水平,看看在梦中的侵略对他们有什么影响。
"Im not saying [gamers] don get more aggressive, not saying theres not more problems with addiction, and not saying theres not obesity issues," Gackenbach said. "As with everything else, theres a balance."
Gackenbach说:“我并不是说,游戏玩家没有更具侵略性;也不是说,游戏成瘾没造成更多问题;也不是说,没有过度肥胖的问题,有一个在这所有问题中的平衡点”。