托福阅读背景知识（四）

　　Coffee doesn’t have the same reputation; indeed, some report that it makes them feel like their nerves are jangling. Yet there is some evidence that it too may protect against long-term mental health problems. A recent “meta-analysis” (summarising the results of studies involving more than 300,000 participants) found that each cup of coffee a day seems to reduce your risk of developing depression by around 8%. In contrast, other beverages (such as sweetened soft drinks) only increase your risk of developing mental health problems.

　　咖啡并没有这种功效;事实上，有些人觉得咖啡会让人有些神经错乱。但是也有证据表明，咖啡能预防长期精神问题。最近的一项“荟萃分析”(总结了超过30万名参与者的研究结果)发现，每天一杯咖啡的人患抑郁症的风险比常人要低大约8%。相比之下，其他饮料(如甜味软饮)只会增加患精神疾病的风险。

　　Verdict: Based on this limited evidence, it’s a draw.

　　结论：基于有限的证据，平局。

　　…and a balm for bodies……

　　身体的万金油

　　Similarly tantalising, though preliminary, epidemiological studies have suggested that both coffee and tea offer many other health-giving benefits. A few cups of either beverage a day appears to reduce your risk of diabetes, for instance.

　　流行病学研究虽然才刚刚起步，但也很吸睛。该领域研究表明，咖啡和茶都对身体还有其它益处。例如，每天喝几杯会降低患糖尿病的风险。

　　Both drinks also seem to moderately protect the heart, although the evidence seems to be slightly stronger for coffee, while tea also appears to be slightly protective against developing a range of cancers – perhaps because of its antioxidants.

　　饮用这两种饮料能对心脏起到一定的保护作用，尽管证据显示似乎咖啡的功效更强，但许是因为茶中的抗氧化剂，茶对预防癌症也有些许功效。

　　Verdict: Another draw – both drinks are a surprising, health-giving elixir.

　　结论：还是平局——这两种饮料都是神奇的、有益健康的灵丹妙药。

　　Overall verdict: Much as we Brits would have liked tea to come out the clear victor, we have to admit there is little between the two drinks besides personal taste. Based solely on the fact that it allows you to get a better night’s sleep, we declare tea the winner.

　　总结：大部分英国人都会觉得茶很明显更胜一筹。但除了个人口味，必须承认的是两者的差异并不大。仅仅基于能让人好眠这一点，茶无疑是赢家。

　　Vocabulary

　　pigment: 色素

　　dental enamel: 牙釉质

　　antioxidant: 抗氧化剂

　　elixir: 万能药

四、托福阅读背景知识：外星人来地球度假

　　Government officials believe aliens may visit Earth and suggest harnessing UFO technology for UK defences, files say.

　　Documents from the Ministry of Defence classified archives show staff believed aliens could visit for “military reconnaissance”, “scientific” research or “tourism”.

　　In a 1995 briefing now published by the National Archives, a desk officer said the purpose of reported alien craft sightings “needs to be established as a matter of priority”, adding there did not appear to be “hostile intent”.

　　The unnamed official said it was “essential that we start with open minds”, explaining “what is scientific ‘fact’ today may not be true tomorrow”.

　　Clarifying he did not “talk to little green men every night”, he said: “We have a remit that we have never satisfied. That is, we do not now (sic) if UFOs exist.

　　“If they do exist, we do not know what they are, their purpose or if they pose a threat to the UK.

　　“If the sightings are of devices not of the earth then their purpose needs to be established as a matter of priority. There has been no apparent hostile intent and other possibilities are: 1) Military reconnaissance; 2) Scientific; 3) Tourism.”

　　He added that “if reports are taken at face value” they showed extraterrestrial vehicles had “a very wide range of speeds and are stealthy”.

　　Thus, he suggested, “we could use this technology, if it exists”.

　　His briefing document lists possible reasons for UFO sightings, including mass hallucinations, US aircraft, “atmospheric events” and hoaxes, but indicated none provide a fully convincing explanation.

　　It adds there are “some indications that the reported incidents are only the tip of an iceberg and many people do not wish to risk embarrassment and so do not report sightings”.

　　He also noted that the number of reports of “strange objects in the skies” increased dramatically after the Second World War, with most sightings coming from “farmers, policemen, doctors and lovers”.

　　在英政府公布的一批有关UFO的机密文档中，英政府官员称外星人可能造访地球，并提议利用外星人高超的飞行器技术为英国国防服务。

　　国防部机密档案的文件显示，有官员认为外星人造访地球可能是为了进行军事侦察，科学研究，或者度假观光。

　　在国家档案馆公布的一份1995年的简报中，一名事务员称应首先确认报告中的外星人乘飞行器到地球的目的，并称他们看起来并无“敌意”。

　　这位匿名官员还说：“重要的是，我们要有开放的思想，”并解释道“今天的科学‘事实’，到了明天可能并不正确。”

　　他澄清他从未“夜夜与小绿人谈话。”他说：“有一项工作我们一直没能实现。那就是，我们不知道UFO是否存在。”

　　“如果他们确实存在，我们也并不知道他们是什么物种，有什么目的，或是否会对英国造成威胁。”

　　“如果这些目击事件所观测到的装置不是地球上的，那么应首先确认这些外来者的目的。目前并未发现他们有明显的敌意，其他的可能目的有：1)军事侦察;2)科学研究;3)度假观光。”

　　他还说“若从表面上来看报告的内容”，外星人使用的交通工具速度奇快，而且应该具有隐形功能。

　　因此，他提议：“如果这种交通工具存在，我们可以利用它的技术。”

　　他在简报文件中列出了出现UFO目击事件的几种可能，其中包括集体幻觉，可能看到的是美国飞行器，可能是某种大气现象，甚至可能是恶作剧，但都没有做出能够完全令人信服的解释。

　　报告中还“暗示报告上来的UFO目击事件只是冰山一角，因为怕尴尬等原因，许多人并没有对政府报告自己的‘发现’。”

　　他还指出，在二战之后，报告“天空中出现奇异物体”的事件出现了迅猛增长，大部分报告者为“农民、警察、医生以及情侣”。