The Mini.doc

The Mini-Lecture of TEM81. CamelA camel can travel hundreds of miles, over several days, without stopping to drink.On todays Moment of Science, well learn how camels survive the dry desert.Lets start with the hump. Contrary to what you might have heard, camels do not store extra water here. The hump stores fat, providing energy for their long, desert trek. This fat, however, can help keep a camel from getting thirsty. As the fat is burned, water is produced as one of the byproducts. This extra water enters the camels bloodstream to add to its water supply.Camels conserve water by not sweating as much as we do. A camels metabolism lowers at night, making its body temperature much lower than a humans. Because we sweat to cool ourselves off, starting with a lower body temperature means less need to sweat. Camels are also covered with heavy fur which keeps the daytime heat out. Because its so good at keeping its cool, a camel can travel a long way without sweating very much.Camels are also good at maintaining their blood volume. Once we humans lose about twelve percent of our bodys water, our blood becomes too thick to work properly. A camels blood, however, stays more or less consistent, allowing the camel to lose up to twenty-five percent of its weight by dehydration.Another thing that helps a camel conserve water is its nasal passages. When we exhale, we loose a lot of water vapor, as any fogged up car window will prove. Camels have extra dry nasal passages which actually recondense the water out of each breath, allowing much less to escape.As you can see, there is no single explanation for a camels desert survival abilities. Instead, a camel draws on a whole range of adaptations.译文：骆驼可以行走数百英里，并在几天之内也不用喝水。在今天的科学一刻中，我们将会学习骆驼是怎样在干燥的沙漠中生存的。我们先从驼峰说起，和你所听说的不一样的是，骆驼并没有储存多余的水在这里。驼峰积聚着脂肪，为它们长距离的沙漠旅行提供能量。然而就是这些脂肪，可以帮助骆驼止渴。水就是这些脂肪燃烧所产生的副产物之一。这些额外的水进入骆驼的血液，增加其水分的供应。骆驼不像我们那样出汗，这样也可以储存水分。骆驼的新陈代谢到晚上就会降低，让它的体温低于人类。出汗可以冷却我们自己，因此如果体温较低的话，对汗水的需求也会比较少。骆驼同样覆盖着厚重的皮毛，这些皮毛可以防止白天的热量进入体内。正因为骆驼如此擅长保持其身体的冷却，所以它可以走很长时间，却不会流很多汗。骆驼同样也很擅长保持它们的血容量。我们人类一旦流失了身体百分之十二的水分，血液就会变得太浓稠以至于不能正常工作。可是骆驼的血液，总是可以坚持到让其脱水到其重量的百分之二十五。另一个有助于骆驼储存水的东西就是鼻腔。当我们呼气的时候，我们会流失许多水蒸汽，被雾气模糊的车窗可以证明这一点。骆驼有额外的干燥鼻腔，可以凝聚每次呼吸的水分，让水分的蒸发的变少。就如你所见，没有关于骆驼沙漠生存能力的单一解释。相反地，骆驼有一系列的适应能力。2. Oceans Most Wanted 外来物种入侵伴随着人们的经济活动和国际交往，一些物种由原生存地借助于人为作用或其他途径移居到另一个新的生存环境并在新的栖息地繁殖并建立稳定种群，这些物种被称为外来物种。我国是世界上海洋生物多样性最丰富的国家之一，被国际保护组织誉为“生物多样性大国”和“生物多样性全球热点地区”。但随着我国海洋运输事业的发展、国际贸易的日趋频繁、海水养殖品种的传播和移殖，我国海洋外来物种数量越来越多，对我国的海洋生物多样性和海洋生态系统安全带来了严重影响。以养殖生物为例，鲍、牡蛎、扇贝、对虾、鱼类、藻类等大量从国外引入亲体，甚至新物种，在养殖过程中由于各种方式导致养殖对象进入自然海域，不仅与当地土著生物争夺生存空间、饵料，争夺生态位，并且传播疾病、与土著生物杂交导致遗传污染，降低土著生物的生存能力，导致土著生物自然群体降低，甚至濒于灭绝。 They might seem innocent and lovely in your (1)aquarium, but released into the wild, your plants and fish can knock aquatic ecosystems right out of balance. Todays invasive species: the (2)water hyacinth.Native to the Amazon basin, but considered an ornamental aquarium plant, the water hyacinth was introduced to Florida in 1884. By the mid-1950s, water hyacinths were clogging Floridas water ways and interfering with navigation, not to mention displacing the native species. Clean up took millions of dollars, and theyre still spreading on every continent except Antarctica.Guess how many of the species on the International Union for the Conservation of Natures list of the one-hundred worst (3)invasive species are the result of aquarium and ornamental releases?How many?A full third! You see, when it comes to aquarium animals and plants, were dealing with mature adults, and particularly hardy ones at that, since the weaker ones dont survive transport. So whenever theyre released into the environment, either intentionally or accidentally, theyre better able to establish themselves.Despite all this, until recently researchers have largely ignored the role of pet fish and aquarium plants when studying the spread of exotic and invasive species. Finally, its time for some guidelines(指导方针), especially ones that encourage the trade of less invasive and aggressive species, or the substitution of native and/or safer species that people could grow instead.译文：在你的水族箱里它们或许看起来很天真，很可爱。但是一旦被放生到野外，你的植物和鱼就会打破水生生态系统的平衡。今天的入侵物种是：水葫芦。水葫芦原产于亚马逊河流域，但作为一种观赏性水生植物，在1884年被引入佛罗里达州。到20世纪中期，水葫芦就造成了佛罗里达州水路的堵塞，干扰航运，更何况还取代了本地物种。尽管清理花费了数百万美元，但是它们仍然在除南极洲以外的各大洲蔓延。你猜猜在国际自然保护联盟的最严重的100个入侵物种名单里，有多少是因为水族箱和观赏性放生造成的？有多少呢？整整三分之一！你知道的在选取水族馆动植物品种时，我们一般选用已长大成熟的动植物，尤其是易养活的那类，因为其他那些相对脆弱的动植物在运输的路途上无法存活下来。因此不论他们何时被放生到外界，故意的或是无意的，它们都能够很好的适应生存。尽管如此，直到最近研究者们在研究外来入侵物种时都很大地忽略了宠物鱼和水生植物所扮演的角色。最后，是时候该制定一些指导方针了，特别是针对减少入侵和侵略物种交易的规定，或者取而代之种植一些本地的和更安全的物种。Notes:(1)aquarium kwrim n.水族馆；养鱼池；玻璃缸Visit an aquarium shop and watch how fish swim.参观一间水族店，观察鱼类如何游泳。(2)water hyacinth 水葫芦；凤眼兰；凤眼蓝(3)invasive inveisiv adj.侵略性的；攻击性的Now, what type of invasive lobular carcinoma is it?那么，是什么亚型的浸润性小叶癌呢？3. Cosmic Radiation 宇宙辐射上世纪早期，科学家发现一种神秘的辐射形式会破坏他们的实验。后来奥地利物理学家Victor Hess研究发现辐射可能来自天空。后来他多次坐热气球用各种仪器（包括测量放射电荷的验电器）收集资料。一次热气球旅行时，遇到日全食，他发现辐射的放射量维持不变，而推定辐射来自宇宙而非太阳。外太空的辐射蕴含带电的核分子，大多是质子（带正电），可以穿透大气层，引发基因突变和癌症。有资料表明每年有十万多人死于来自太空辐射引发的癌症。人们是怎么推断出癌症是因宇宙辐射产生？太阳辐射和宇宙辐射具体有什么区别？臭氧空洞和地球磁场减弱都让人们遭受更多的辐射，那么是否有办法能够阻挡宇宙辐射的侵害？Did you know that cosmic radiation is up to one-hundred times greater at cruising altitude than on the ground? Learn more on this Moment of Science. Did you know that cosmic radiation is up to one-hundred times greater at cruising altitude（巡航高度） than on the ground? If you need another reason to dislike flying, this Moment of Science is for you.Like all radiation, cosmic radiation is made of electrically charged particles（带电粒子）such as protons（质子） and ions（离子）.These particles drift to earth from space: The sun is a major source, especially during solar flares(太阳耀斑). Just like more familiar forms of radiation, for example Radon and X-rays, high dose cosmic radiation may be associated with health problems such as cancer.Luckily, most cosmic radiation is screened out (遮挡)by our atmosphere before it ever reaches the ground. At sea level, the atmosphere is thick and screens out a lot, but at high altitudes, such as the cruising altitudes of many commercial airplanes, we are less protected.Is this a reason to avoid flying? Well, not really. While radiation levels are greater in aircraft than on the ground, your overall dose is still quite small. You would need to spend thousands of hours in the air to suffer even a slight increase in your risk of health problems. But, cosmic radiation might be a concern for flight crews, who fly day after day over many years. For most of us, when it comes to cosmic radiation we are on pretty safe ground.注释：巡航高度（cruising altitude）：飞机完成起飞阶段进入预定航线后的飞行状态称为巡航。飞机发动机有着不同的工作状态，当发动机每公里消耗燃料最少情况下的飞行速度，称为巡航速度。飞机以多大的速度飞行，要根据飞机飞行的距离、所需的时间、载荷要求、飞行的安全性、发动机的耐久性和经济性，以及气候条件等情况确定的装有不同发动机的飞机，其巡航速度、巡航高度和航程是不一样的。太阳耀斑（solar flares）：太阳耀斑是一种最剧烈的太阳活动。周期约为11年。一般认为发生在色球层中，所以也叫“色球爆发”。其主要观测特征是，日面上（常在黑子群上空）突然出现迅速发展的亮斑闪耀，其寿命仅在几分钟到几十分钟之间，亮度上升迅速，下降较慢。特别是在，耀斑出现频繁且强度变强的时候。4. Proton Therapy 对抗癌症-质子方法质子疗法也叫质子刀，是放射治疗的一种，比普通的放射疗法更有针对性。质子作为带正电荷的粒子，以极高的速度进入人体，由于其速度快，在体内与正常组织或细胞发生作用的机会极低，当到达癌细胞的特定部位时，速度突然降低并停止，释放最大能量，发生Bragg峰（博拉格峰），将癌细胞杀死，同时有效地保护正常组织。由于质子治疗具有穿透性能强、剂量分布好、局部剂量高、旁散射少、半影小等特征，尤其对于治疗有重要组织器官包绕的肿瘤，显现出较大的优越性。质子治疗的适应症比拟广泛，对于脑部良恶性肿瘤、脊髓肿瘤、脑血管疾病、头颈部肿瘤、眼部病变、胸腹部肿瘤、儿科肿瘤以及其它疾病等均有较好的疗效。国外临床治疗数据标明，质子治疗肿瘤有效率达到95%以上，五年存活率高达80%，被高能物理界和医学界评估为疗效最好、副作用最少的治疗方法。Doctors have developed a promising new procedure that could (1)revolutionize the way we fight cancer. Learn about proton therapy on this Moment of Science. If you or someone you know has had cancer, then you know how frightening and painful treatment can be. But during the past few decades doctors have developed a promising new procedure called proton therapy that could revolutionize the way we fight cancer.Proton therapy is basically a new kind of radiation treatment. Until recently, all radiation therapy used X-Rays. X-Rays are good at destroying cancer cells, but the problem is that when they pass through the body, they attack not only cancer cells but also surrounding healthy cells. So doctors have been forced to use radiation doses low enough to minimize damage to non-cancerous cells.Proton therapy is a more accurate way of attacking cancer with radiation. Unlike X-Rays, which go through a patient and out the other side, protons penetrate only to the desired point and then stop. So cells deeper in the body than where the tumor is are not affected.Protons also release most of their destructive energy just before they stop, so healthy cells in front of the tumor get less radiation than the cancer cells do. Proton therapys accuracy means that doctors can train high doses of proton radiation on (2)tumors without worrying about causing (3)collateral damage.Proton radiation is not a miracle curein fact, its limited to treating (4)localized cancers that have not spread throughout the body. Still, its an important new tool for battling a deadly disease, especially for tumors deep inside the head or neck, where doing surgery would be too risky.译文：如果你或你认识的人得了癌症，你就会知道治疗的过程是何其的可怕和痛苦。但是在过去的几十年里医生们已经研发出一种新的有前景的治疗过程，叫做质子治疗。质子治疗可以彻底改变我们对抗癌症的方法。质子治疗从根本上说是放射疗法的一种。直到最近，所有的放射疗法都是采用的X射线。X射线能够摧毁癌细胞，但问题是当穿过身体时，它们不仅攻击癌细胞，也同样会攻击周围的健康细胞。所以医生们一直被迫使用较低的辐射剂量来减少对非癌细胞的伤害。质子疗法是用辐射治疗癌症一种更为准确的方法。与X射线不同的是，穿过病人身体并从身体的另一边出去时，质子只会穿透所需要的点，然后就停止。因此，在人体内比肿瘤位置更深的细胞不会受到影响。质子一停下来就会释放大部分的破坏性能量，所以肿瘤外部的健康细胞比癌细胞受到的辐射少。质子治疗的精确性意味着医生们可以在肿瘤的治疗上使用高剂量的质子辐射，并且不用担心会引起附带损害。质子放射疗法其实并不是一个治疗的奇迹。它仅局限于治疗没有扩散到全身各处的局部肿瘤。不过它仍然是一个对抗致命疾病的重要工具，特别是对于头部和颈部深处的肿瘤，在那里做手术太冒险了。Notes:(1)revolutionize ,revlju:naiz vt.发动革命；彻底改革；宣传革命 vi.革命化；从事革命1.They wanted to revolutionize the whole world. 他们要在全世界发动革命。2.But the Internet has just as much potential to revolutionize education. 不过，互联网同样具有实现教育革命的潜力。(2)tumors n.肿瘤（tumor的复数）(3)collateral damage 法附带损害The collateral damage is still considerable.间接的损失仍然相当大。(4)localizedluklaizd adj.局部的；地区的；小范围的 v.定位（localize的过去分词）Their interest localized on the development of this new drug.他们的兴趣集中在这种新药的研制开发上。5. Bye-bye Chicago? 永别了，芝加哥？Although it is devastating to find out that Chicago is sinking, were only talking one millimeter a year. Thats four inches in a century, but only until the land in North America brings itself back into equilibrium.When glaciers covered Canada and the northern Great Lakes tens of thousands of years ago, their weight pushed down on the Earths surface and caused it to sag. And this pressure forced the Earths mantle, the layer of hot, plastic rock thats located beneath the Earths crust, to give way and ooze out and sideways. Its like the Earth is a giant waterbed. When you lie down on it, the surface of the mattress under you sinks, forcing the water into other parts of the mattress.In the twelve thousand years since the glaciers receded, the Earths crust has been slowly returning to its original shape. So the land in Canada and the northern Great Lakes is slowly rising, while the rest of North America is slowly sinking, like a seesaw, enabling the mantle to flow back north. And as the Lake Michigan floor north of Green Bay rises, all that water sloshes south towards Chicago.6. Less Use of Air Conditioners would be Better for Us AllA strict no-air-conditioning ban was enforced for 87,000 Taiwanese students taking the college entrance examinations this month despite temperatures in many areas reaching 34 to 36 degrees Celsius. Although this long-term practice is being promoted as a pragmatic means to ensure fairness, since air conditioning is not available at all exam locations, rather than for environmental reasons, it nevertheless offers a good opportunity for the country to reconsider its addiction to air conditioning. If students can manage without A/C in the heat of examinations, could not the rest of the population go cold turkey once in a while? If not Off, then Down, since air conditioners consume energy and contribute to climate change in proportion to each degree they are set below ambient temperature. Vehicle A/C systems can be a cause of sinusitis in some people, while poorly maintained air conditioning may lead to the proliferation of micro-organisms such as Legionella pneumophila, the cause of Legionnaires disease. The problem with new high-tech machines is that they present a sizable contribution to man-made climate change. Cooling agents such as CFCs and their modern replacements are greenhouse gases with far more global-warming potential than carbon dioxide should they leak into the atmosphere. It is everyones responsibility to minimize his or her own contribution to the problem.ban:禁令；禁止pragmatic:务实的，实用的addiction：成癮；入迷proportion：比例；比率ambient：周遭的，环绕的proliferation：（生物）增殖；激增，扩散to go cold turkey：戒除坏习惯7. 识别真假英镑Ever since money was invented there have been people trying to fake it. Thats why its important for everyone to know how to spot a fake banknote. And the best thing to do is to know by heart what genuine notes should look like. Here is our expert Lee Dobney. Hello Im Lee Dobney, Im the head of notes division at the Bank of England. And in the next few minutes, Lee will guide us through some key features to look out for in British banknotes. Bank note is very different from ordinary paper because its made from cotton rather than wood pulp, so bank note paper has a unique feel.And also theres the raised printing. So for instance, on the front of the note, thats the side features the Queens portrait, if you run your fingers over the Bank of England sign, you can feel the raised print. And also in the bottom right hand corner you can also feel raised printing with the small twenties. The second feature to look out for would be the watermark. Now thats made during the paper making process and creates an image using thicker and thinner areas of paper. So on all our banknotes the image is of the Queen, and if you hold the note up to the light you can see the queens portrait. The third security feature is the hologram. Now a hologram is the brightly coloured image which also shifts. So for instance, on the new twenty pound note design, there is a shift between the pound sign and the twenty, and also a very colourful image of Adam Smith, the economist and philosopher.banknote:钞票，纸币genuine note：真钞pulp：果肉，纸浆portrait：画像watermark：水印hologram：全息图8. 发现号安全返回Last Updated Tue, 09 Aug 2005 17:48:34 EDTThe repairs made to the space shuttle Discovery while it was in orbit are the first step toward other missions in the solar system, a returning astronaut said Tuesday. Discovery lands in California Tuesday. (Courtesy: NASA TV) Discoverys landing completes the first shuttle mission since Columbias seven astronauts were killed during re-entry in February 2003. Lightning and rain near the Kennedy Space Center in Florida forced Discoverys crew to land at Edwards Air Force Base in California.The 14-day mission included an unprecedented spacewalk to remove two pieces of dangling tiles on the shuttles heat shield while it was docked at the International Space Station. Astronaut Steve Robinson was held in place by the stations Canadarm2 robotic arm as he pulled out the pieces, which NASA feared might cause heating problems during re-entry. As people prepare to explore the moon and Mars, astronauts will need to learn how to make such repairs in orbit, Robinson noted.The first step is to show we could get access, and access is everything, Robinson told a post-flight news conference.The crews two major acc