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microscopicmess9Climate Change Poses Major Risks for Unprepared CitiesA new examination of urban policies has been carried out recently by Patricia Romero Lankao. She is a sociologist specializing in climate change and urban development. She warns that many of the worlds fast-growing urban areas, especially in developing countries, will likely1 suffer from the impacts of changing climate. Her work also concludes that most cities are failing to reduce emissions of carbon dioxide and other greenhouse gases. These gases are known to affect the atmosphere. “Climate change is a deeply local issue and poses profound threats to the growing cities of the world,” says Romero Lankao. “But too few cities are developing effective strategies to protect their residents. ”Cities are major sources of greenhouse gases. And urban populations are likely to be among those most severely affected by future climate change. Lankaos findings3 highlight ways in which city-residents are particularly vulnerable, and suggest policy interventions that could offer immediate and longer-term benefits The locations and dense construction patterns of cities often place their populations at greater risk for natural disasters. Potential threats associated with climate include storm surges and prolonged hot weather. Storm surges can flood coastal areas and prolonged hot weather can heat heavily paved cities more than surrounding areas. The impacts of such natural events can be more serious in an urban environment. For example, a prolonged heat wave can increase existing levels of air pollution, causing widespread health problems. Poorer neighborhoods that may lack basic facilities such as drinking water or a dependable network of roads, are especially vulnerable to natural disasters. Many residents in poorer countries live in substandard housing without access to reliable drinking water, roads and basic services.Local governments,therefore,should take measures to protect their residents. “Unfortunately, they tend to move towards rhetoric rather than meaningful responses,” Romero Lankao writes. “They dont impose construction standards that could reduce heating and air conditioning needs. They dont emphasize mass transit and reduce automobile, use. In fact, many local governments are taking a hands-off approach.” Thus, she urges them to change their idle policies and to take strong steps to prevent the harmful effects of climate change on cities.Free Statins With Fast Food Could Neutralize Heart RiskFast food outlets could provide statin drugs free of charge so that customers can reduce the heart disease dangers of fatty food, researchers at Imperial College London suggest in a new study.Statins reduce the amount of unhealthy “LDL” cholesterol in the blood. A wealth of trial data4 has proven them to be highly effective at lowering a persons heart attack riskIn a paper published in the American Journal of Cardiology, Dr Darrel Francis and colleagues calculate that the reduction in heart attack risk offered by a statin is enough to offset the increase in heart attack risk from eating a cheeseburger and drinking a milkshake.Dr Francis, from the National Heart and Lung Institute at Imperial College London, who is the senior author of the study, said: “Statins dont cut out all of the unhealthy effects of cheeseburgers and French fries. Its better to avoid fatty food altogether. But weve worked out that in terms of your possibility of having a heart attack, taking a statin can reduce your risk to more or less the same degree as a fast food meal increases it. ”Its ironic that people are free to take as many unhealthy condiments in fast food outlets as they like, but statins, which are beneficial to heart health, have to be prescribed. It makes sense to make risk-reducing statins available just as easily as the unhealthy condiments that are provided free of charge. It would cost less than 5 pence per customer not much different to a sachet of sugar, “ Dr Francis said.When people engage in risky behaviours like driving or smoking, theyre encouraged to take measures that lower their risk, like wearing a seatbelt or choosing cigarettes with filters. Taking a stain is a rational way of lowering some of the risks of eating a fatty meal.Better Solar Energy Systems: More Heat, More LightSolar photovoltaic thermal energy systems, or PVTs, generate both heat and electricity, but until now they havent been very good at the heat-generating part compared to a stand-alone solar thermal collector. Thats because they operate at low temperatures to cool crystalline silicon solar cells, which lets the silicon generate more electricity but isnt a very efficient way to gather heat. Thats a problem of economics. Good solar hot-water systems can harvest much more energy than a solar-electric system at a substantially lower cost. And it，s also a space problem：photovoltaic cells can take up all the space on the roof, leaving little room for thermal applications. In a pair of studies, Joshua Pearce, an associate professor of materials science and engineering, has devised a solution in the form of a better PVT made with a different kind of silicon. His research collaborators are Kunal Girotra from ThinSilicon in California and Michael Pathak and Stephen Harrison from Queens University, Canada. Most solar panels are made with crystalline silicon， but you can also make solar cells out of amorphous silicon,commonly known as thin-film silicon. They dont create as much electricity, but they are lighter, flexible, and cheaper. And, because they require much less silicon, they have a greener footprint. Unfortunately，thin-film silicon solar cells are vulnerable to some bad-news physics in the form of the Staebler-Wronski effect. “That means that their efficiency drops when you expose them to light pretty much the worst possible effect for a solar cell,” Pearce explains，which is one of the reasons thin- film solar panels make up only a small fraction of the market. However, Pearce and his team found a way to engineer around the Staebler-Wronski effect by incorporating thin-film silicon in a new tpye of PVT. You dont have to cool down thin-film silicon to make it work. In fact，Pearces group discovered that by heating it to solar-thermal operating temperatures，near the boiling point of water, they could make thicker cells that largely overcame the Staebler-Wronski effect. When they applied the thin-film silicon directly to a solar thermal energy collector, they also found that by baking the cell once a day，they boosted the solar cells electrical efficiency by over 10 percent. Sharks Perform a Service for Earths WatersyIt is hard to get people to think of sharks as anything but a deadly enemy. They are thought to attack people frequently. But these fish perform a valuable service for earths waters and for human beings. Yet business and sport fishing3 are threatening their existence. Some sharks are at risk of disappearing from earth.Warm weather may influence both fish and shark activity. Many fish swim near coastal areas because of their warm waters. Experts say sharks may follow the fish into the same areas,where people also swim. In fact, most sharks do not purposely charge at or bite humans. They are thought to mistake a person for a sea animal, such as a seal or sea lion. That is why people should not swim in the ocean when the sun goes down or comes up. Those are the times when sharks are looking for food. Experts also say that bright colors and shiny jewelry may cause sharks to attack.A shark has an extremely good sense of smell4. It can find small amounts of substances in water, such as blood, body liquids and chemicals produced by animals. These powerful senses help sharks find their food. Sharks eat fish, any other sharks, and plants that live in the ocean.Medical researchers want to learn more about the sharks body defense and immune systems against disease. Researchers know that sharks recover quickly from injuries. They study the shark in hopes of finding a way to fight human disease.Sharks are important for the worlds oceans. They eat injured and diseased fish. Their hunting activities mean that the numbers of other fish in ocean waters do not become too great. This protects the plants and other forms of life that exist in the oceans.“Liquefaction” Key to Much of Japanese Earthquake DamageThe massive subduction zone earthquake in Japan caused a significant level of soil “liquefaction” that has surprised researchers with its widespread severity, a new analysis shows.Weve seen localized examples of soil liquefaction as extreme as this before, but the distance and extent of damage in Japan were unusually severe,” said Scott Ashford, a professor of geotechnical engineering at Oregon State University. “Entire structures were tilted and sinking into the sediments,” Ashford said. “The shifts in soil destroyed water, drain and gas pipelines, crippling the utilities and Infrastructure these communities need to function. We saw some places that sank as much as four feet. ”Some degree of soil liquefaction is common in almost any major earthquake. Its a phenomenon in which soils soaked with water, particularly recent sediments or sand, can lose much of their strength and flow during an earthquake. This can allow structures to shift or sink or collapse.But most earthquakes are much shorter than the recent event in Japan, Ashford said. The length of the Japanese earthquake, as much as five minutes, may force researchers to reconsider the extent of liquefaction damage possibly occurring in situations such as this.“With such a long-lasting earthquake, we saw how structures that might have been okay after 30 seconds just continued to sink and tilt as the shaking continued for several more minutes,” he said. “And it was clear that younger sediments, and especially areas built on recently filled ground, are much more vulnerable.”The data provided by analyzing the Japanese earthquake, researchers said, should make it possible to improve the understanding of this soil phenomenon and better prepare for it in the future. Ashford said it was critical for the team to collect the information quickly,before damage was removed in the recovery efforts.Theres no doubt that well learn things from what happened in Japan that will help us to reduce risks in other similar events,” Ashford said. “Future construction in some places may make more use of techniques known to reduce liquefaction, such as better compaction to make soils dense, or use of reinforcing stone columns.”Ashford pointed out that northern California have younger soils vulnerable to liquefaction on the coast, near river deposits or in areas with filled ground. The “young” sediments, in geologic terms, may be those deposited within the past 10,000 years or more. In Oregon, for instance, that describes much of downtown Portland, the Portland International Airport and other cities.Anything near a river and old flood plains is a suspect, and the Oregon Department of Transportation has already concluded that 1100 bridges in the state are at risk from an earthquake. Fewer than 15 percent of them have been reinforced to prevent collapse. Japan has suffered tremendous losses in the March 11 earthquake, but Japanese construction standards helped prevent many buildings from collapse even as they tilted and sank into the ground.Batteries Built by Viruses病毒电池What do chicken pox, the common cold水痘、普通感冒、流感和艾滋病有哪些相似之处呢？这些都是由病毒引起的疾病。病毒是能够在人与人之间传染的微生物。难怪大部分人一提到病毒，首先想到的是如何躲避病毒。然而，并不是每个人都躲避这些疾病携带者。在马萨诸塞州剑桥市，科学家发现有些病毒能起到非同寻常的作用。他们使病毒开始工作，使病毒构成世界上最小的充电电池。病毒和电池的搭档似乎并不常见，但这对于工程师安吉拉，贝尔彻来说却并不陌生。安吉拉，贝尔彻最早产生了这一想法。在位于剑桥市的麻省理工学院，她和合作者一起用新方式融合了不同的科学领域。在由病毒构成的电池里，科学家融合了他们在生物、技术和生产工艺方面的知识。贝尔彻的团队包括帮助组装微型电池的宝拉，哈蒙德和以电池形式存储能量的专家蒋业明。哈蒙德说，“我们现在从事的行业是传统中不会想到的。”许多电池已经很小了。A型、C型和D型电池都可以握在手里。硬币形状的手表电池通常比分币还小。然而，个人音乐播放器和手机等新型电子设备变得越来越小。这些设备变小了，普通理想的电池应当体积小、储能多。目前，贝尔彻的电池模型是完全由病毒构成的金属圆盘，看起来就像普通手表电池。但里面的部件却非常小小到用高倍望远镜才能看到。这些电池部件到底有多小呢？从头上拔一根头发，把它放到白纸上，看看头发的宽度是不是很细呢？尽管每个人的头发宽度不同，每个头发上可以并列排放大约10个病毒电池部件。这些微电池可能会改变我们对病毒的看法。the way we look at viruses1.According to the first paragraph, people try to -Stay away from viruses because they are causes of various diseases.2.What is Belchers team doing at present?-It is making batteries with viruses3.What expression below. is opposite in meaning to the word “shrink” appearing in paragraph 5?-Expand4.Which of the following is true of Belchers battery mentioned in paragraph 6?-It is a metallic disk with viruses inside it.5.How tiny is one battery part?-Its width is one tenth of a hair.Putting Plants to Work植物效能Using the power of the sun is nothing new太阳能的使用已经不足为奇。几十年前，人们就开始使用太阳能计算器，制造太阳能电热板镶嵌的建筑。但是植物当属应用太阳能的专家：十亿年来，植物一直把阳光作为能源资源。绿叶植物细胞的工作就像微型加工厂一样，将阳光，二氧化碳和水转化为糖和淀粉，并且同时储存植物本身所需的能量。这种转换过程叫做光合作用。可惜你不是一株植物，必须困难的并且花上大价钱将阳光转换为稳定的能源。因此，科学家们正在对植株进行准确细致的研究。一些科学家正试图像植物的作用过程一样，将植物，或生物的细胞活动看做微型光合发电站。例如，玛丽亚奇若蒂在美国科罗拉多州的国家可再生能源实验室里对绿藻进行研究。她正想方设法地通过植物的产生氢来取代光合作用产生的糖。一旦研究人员了解藻类如何有效率的进行工作，由此产生的氢气可用于燃料电池动力汽车和发电。在实验室里，藻类生长通过狭窄的颈玻璃瓶生产氢气的环境下。在光合作用下，植物通常产生糖类或淀粉。奇若蒂说： “但在一定条件下，有很多藻类能够利用日光能源产生氢气而不是储存淀粉。”例如，藻类会在空气存在环境下产生氢气。这是因为空气中的氧气，氧阻止绿藻制造氢。藻类在空气中虽然可以工作，但是充满困难。这种方式不能切实可行的生产廉价的能源。但是奇若蒂和她的同事们已经发现，即使在目前的空气条件下，他们从藻类生长的环境中，除去所谓的硫酸化学品，能够产生氢来代替糖。只可惜消除硫酸盐不仅使藻类细胞的工作速度减慢，而且大大减少了氢的数量。尽管如此，研究人员认为，对于实现有效率的利用藻类产生氢这一目标，他们已经迈出了第一步。随着工作量的加大，他们可以加速细胞的活动，从而产生大量的氢气。研究人员们希望，总有一天藻类会成为很容易使用的燃料来源。藻类这种生物极易存活，他们可以在几乎任何地方成长。奇若蒂说：“你可以将它放在一反应堆或是池塘里，也可以在海洋中找到它们，人们可以灵活的使用藻类的用途广泛。”in how you can use these organisms1.What does the writer say about plants concerning solar energy?-Plants have been using solar energy for billions of years.2.Why do some scientists study how plants convert sunlight carbon dioxide, and water into sugars and starches?-Because they want green plants to become a new source of energy3.According to the fifth paragraph, under what conditions are algae able to use solar energy to make hydrogen?-When there is no oxygen in the air4.Researchers have met with difficulties when trying to make algae produce hydrogen efficiently. Which one of the following is one such difficulty?-It is too slow for algae to produce hydrogen when the sulfate is removed.5.What is NOT true of algae?-They are cheap to eat.Listening Device Provides Landslide Early Warning听觉仪器提供早期山崩预警A device that provides early warning 英国研究者们正在测试一种仪器，它可以通过监测土壤振动提供早期山崩预告。科学家们说，这种仪器通过警报某处有险情需要撤离，每年可以拯救成千上万的生命。经历过骤降大雨，地震甚至土壤侵蚀的国家，山崩这样的自然灾害是很常见的。当同一个山坡上的一些土壤或石块开始移动时，山崩就开始了，但早期很难发现。接着这个初始运动，“山坡在数分钟或数小时内变得不稳定，”英国拉夫堡大学尼尔迪克森说。他说，一个监控这种运动的警报系统“足以疏散一个街区的人或清出一条马路，拯救生命”。监视迫近的山崩，最常见的办法就是观察这座山Jp状的变化。研究者们可以直接测量，也可以在钻孔中或者地表面上探测山坡形状的变化。可是，山坡改变形状也未必就导致山崩。所以任何一种方法都可能导致误警。现在，迪克森的团队已发明了一种仪器，它在一个山坡内的颗粒开始移动时可以接收到振动。这个仪器是钢管形状，探人山坡上的一个钻孔中。钻孔中仪器的四周填满沙砾，有助于传导山坡内颗粒产生的高频振动波。振动波顺着钢管上传，被地表传感器接收。通过软件分析振动信号，判断是否马上要发生山崩。目前这种仪器正在英国纽卡斯尔一座6米高人造石灰大坝中接受测试。先期结果显示它比现有的仪器提供较少的判断误差。一旦这种仪器通过了认真彻底的检测，它将成为一个完善的山崩早期预警系统。“受山崩严重威胁的地区一定会从这样的仪器中得益，”英国红十字会的专家艾登，保特说，“只要它不是太贵。”但是，保特又说一个早期预警系统本身并不足以防灾，“你需要建立人际交流，”他说，“使系统发射的预警送达到需要的人群是不容易的事。”who need them can be difficult1.What does “Such natural disasters” in the first paragraph refer to -Landslides.2.Which of the following statements is true of landslides?-All of the above.3.Why do researchers develop a new device to monitor signs of landsides?-Because the common methods can cause false alarms.4.Which of the following statements is NOT true of the device, according to Paragraph 4?-It is filled in with gravel.5.According to the context, what does the word “positives” in the fifth paragraph mean?-Evidences.“Dont Drink Alone” Gets New Meaning“不要在就餐时间以外饮酒”有了新含义In what may be bad news for一定程度上，这对酒吧可能是一个坏消息，欧洲的一个研究小组发现人们在就餐时间以外饮酒会使患口腔和颈部癌症的几率比就餐时饮酒更高。Luigino Dal Maso和他的同事们研究了取自四项癌症研究的1，500个病例的饮酒习惯模式和另外3500个从没患癌症的成年人的饮酒习惯模式。在研究者分析了饮酒的总量后，他们发现和只在就餐时饮酒的人相比，在就餐时间以外灌下大量烈酒的人面临至少50%80%的患口腔癌、咽癌和食道癌的危险。在就餐时间外饮酒也会使患喉癌的可能性增加至少20%。“被研究者的情况说明大约95%患以上四种癌症的原因就是抽烟或饮酒。”Dal Maso说。他的研究小组提供的报告中令人沮丧的消息是就餐时饮酒不会消除患以上任何一种癌症的危险。为了进行新的分析，欧洲科学家根据每星期平均饮酒量将被研究者分为4组。饮酒量最少的一组包括每周平均饮酒量达20杯的人，饮酒量最高的一组每周饮酒至少56杯，平均每天8杯以上。患口腔癌和颈部癌的危险随着饮酒量而稳定上升，即使是那些只在就餐时饮酒的人。例如，和低饮酒量的人相比，每周饮酒2134杯的人患除喉癌以外其他部位的癌症的危险增加了一倍。如果这几组中的人在就餐时间以外饮酒，那些属于高饮酒量组的人会使他们患口腔癌和食道癌的危险至少增加3倍。和每周只在就餐时平均饮酒至多20杯的人相比，高饮酒量组的人在就餐时间饮酒患口腔癌的危险是低饮酒量组的10倍，咽癌是其7倍，食道癌是16倍。相反，酒精高摄入且仅在就餐时饮酒的人患喉癌的危险是酒精低摄人且仅在就餐时饮酒的人的3倍。“酒精能使组织发炎，一段时间后，炎症可引发癌症。”Dal Maso说。他认为食物降低了患癌症的危险，或是通过覆盖在消化道组织上或是通过将酒精从那些组织上擦掉。他推测所有被研究者患喉癌的几率比其他癌症低很多的原因是喉部组织被酒精侵害到的部分少得多。tissues lower exposure to alcohol.1.Researchers have found that the risk of cancer in the mouth and neck is higher with people -who drink alcohol outside of meals2.Which of the following is NOT the conclusion made by the researchers about “drinking with meals”?-It increases by 20 percent the possibility of cancer in all sites3.Approximately how many drinks do the lowest-intake group average per day?-3 drinks4.Which cancer risk is the lowest among all the four kinds of cancer mentioned in the passage?-Laryngeal cancer5.According to the last paragraph, tissues lower exposure to alcohol -reduces the risk of laryngeal cancer.“Life Form Found” on Saturns Titan土卫六上发现了生命迹象Scientists say they have discovered hints 科学家们说，在土卫六上发现了外星生命迹象并宣布了这一发现。美国国家航空航天局( NASA)的研究者们对卡西尼号探测器所传回来的数据进行了分析，数据表明，土星卫星中最大的一颗卫星有以甲烷为基础的生命的存在迹象。据报道，科学家们已经找到了在土卫六高浓度氢气大气层里“呼吸”的原始外星生命的线索。他们认为，氢气在到达布满甲烷河流湖泊的土卫六类似行星一样的表层前就已经被吸收了。这就证明在这个不及半个地球大小的卫星表面有某种微生物在依靠氢气生存。美国国家航空航天局的科学家Chris Mckay说，“我们提出有氢气的消耗，是由于它是土卫六上生命赖以生存的显而易见的气体，就像我们地球上用氧气呼吸一样。如果这些迹象最终证明是生命的迹象，它会加倍令人兴奋，因为它会代表完全不同于地球上水基生命的第二种生命。”时至今日，尽管地球上的依赖液体水的微生物在甲烷里生长良好或把它作为废物排出，科学家在任何地方都没有探测到这种生命的形式。在土卫六上，绝对温度达到90度（相当于摄氏-273.15度），依赖于甲烷的微生物不得不用某种液体物质作为生存的介质，这种液体不是水，水在土卫六上会冻成冰块，不能融化。我们知道，冰块太冷不能维持生命。科学家们原指望太阳与大气层中的化学物质相互作用会在土卫六上产生一层乙炔。但卡西尼号在它的表面没有探测到乙炔。Mark Allen是美国宇航局土卫六项目组的主要负责人，他说道，既然在土卫六的表面没有探测到乙炔，那就充分说明上面没有生物。Allen说：“科学界的保守主义者们建议，要做出土卫六上有生物的结论，首先必须对土卫六上所有没有生物的观点做出回应；要排除土卫六上可能没有生物的观点，我们任重道远。极为可能的是，一种化学过程而非生物学能解释这些结果。”can explain these results.1.What have scientists found about Saturn?-They have found methane-based life on Titan2.What do scientists say about Titan?-There are life clues there3.To date, scientists have not yet detected this form of life.(paragraph 5) What does “this form of life” refer to?-Methane-based life.4.What can be inferred from what Allen said?-Scientists have different arguments over whether there is life on Titan.5.Which of the following can replace the title of this passage?-A different Life Form, a PossibilityClone Farm克隆农场Factory farming could soon enter a new工业化农场很快会进入一个大产量的新领域。美国的公司正在开发一项需要大规模克隆小鸡的技术。一旦一个具有所期望特性的小鸡被孵化出来或被基因改造，每小时成千上万的鸡蛋就会滚下生产线，这些鸡蛋将孵出如出一辙的小鸡。每年数以十亿只计的克隆小鸡能被孵化出来，从而为鸡场提供以相同比例生长、重量相同并且味道相同的小鸡。这至少是美国国家科技院的梦想，科技院给Origen Therapeutics of Burlingame，California，以及Embrex of North Carolina 470万基金以资助研究。这个预想为担忧增加鸡场小鸡痛苦的动物福利组织拉响了警报。那好像并没有令家禽养殖业气馁，然而，他们想使抗病小鸡吃得更少，长得更快。“养殖者希望减少投入但仍获得相同的产量，”Mike Fitzgerald of Origen说。为了达到这个要求，Origen致力于“制造一个有效克隆体的小鸡，”他说。正常的克隆技术对禽类无效，因为卵不能被移动或移植。然而，公司正试图从刚产下的受精卵中大量繁殖胚胎干细胞。 “诀窍是在细胞开始显示其差别前对其进行培育，这样它们还保持发育灵活性，”Fitzgerald说。运用早已成熟的技术，这些干细胞会被注入刚产出、已经受精的鸡蛋的胚胎中，形成一个嵌合体的小鸡。严格地说，嵌合体的小鸡不是克隆鸡，因为它既有植入的细胞又有本身的细胞。但Fitzgerald说，如果小鸡身体的95%是由被植入的细胞发展而来的就足够了。 “在家禽界，不是100%也没关系。”Origen面临的另一个挑战是提高生产量。为了做到这点，他和Embrex合作研制了一个可将疫苗在一小时内注入50000个鸡蛋中的仪器。 Embrex正试图改造那个仪器，从而使胚胎和注射的细胞落在准确的位置而不杀死它。在将来，Origen设想将不同品种小鸡的干细胞冷冻，如果订单要某一种小鸡，成百万的卵能在几个月甚至几个星期被生产出来。目前，维持市场可能需要的所有品种小鸡对养殖者来说太昂贵了，而且要花数年的时间才能培育足够多的小鸡以生产出农民需要的数以十亿只计的鸡蛋。billions of eggs that farmers need1.Which statement is the best description of the new era of factory farming according to the first paragraph?-Cloned chickens are bulk-produced with the same growth rate, weight and taste2.Which institution has offered $4.7 million to fund the research?-The USs National Institute of Science and Technology3.In the third paragraph, by saying “Producers would like the same meat quantity but
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