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1、+第一篇 Captain Cook Arrow Legend(庫(kù)克船長(zhǎng)弓箭的傳說(shuō))It was a great legend while it lasted, but DNA testing has finally ended a two-century-old story of the Hawaiian arrow carved from the bone of British explorer Captain James Cook who died in the Sandwich Islands in 1779.“There is no Cook in the Australian Mus
2、eum,” museum collection manager Jude Philip said not long ago in announcing the DNA evidence that the arrow was not made of Cooks bone. But that will not stop the museum from continuing to display the arrow in its exhibition, “Uncovered: Treasures of the Australian Museum,” which does include a feat
3、her cape presented to Cook by Hawaiian King Kalaniopuu in 1778.Cook was one of Britains great explorers and is credited with discovering the “Great South Land,” now Australia, in 1770. He was clubbed to death in the Sandwich Islands, now Hawaii.The legend of Cooks arrow began in 1824 when Hawaiian K
4、ing Kamehameha on his deathbed gave the arrow to William Adams, a London surgeon and relative of Cooks wife, saying it was made of Cooks bone after the fatal fight with islanders.In the 1890s the arrow was given to the Australian Museum and the legend continued until it came face-to-face with scienc
5、e.DNA testing by laboratories in Australia and New Zealand revealed the arrow was not made of Cooks bone but was more likely made of animal bone, said Philp.However, Cooks fans refuse to give up hope that one Cook legend will prove true and that part of his remains will still be uncovered, as they s
6、ay there is evidence not all of Cooks body was buried at sea in 1779. “On this occasion technology has won,” said Cliff Thornton, president of the Captain Cook Society, in a statement from Britain. “But I am sure that one of these days one of the Cook legends will prove to be true and it will happen
7、 one day.”+第二篇 Avalanche and Its Safety(雪崩和安全問(wèn)題)An avalanche is a sudden and rapid flow of snow, often mixed with air and water, down a mountainside. Avalanches are among the biggest dangers in the mountains for both life and property.All avalanches are caused by an over-burden of material, typicall
8、y snowpack, that is too massive and unstable for the slope that supports it. Determining the critical load, the amount of over-burden which is likely to cause an avalanche, is a complex task involving the evaluation of a numberof factors.Terrain slopes flatter than 25 degrees or steeper than 60 degr
9、ees typically have a low risk of avalanche. Snow does not gather significantly on steep slopes; also, snow does not flow easily on flat slopes. Human-triggered avalanches have the greatest incidence when the snows angle of rest is between 35 and 45 degrees; the critical angle, the angle at which the
10、 human incidence of avalanches is greatest, is 38 degrees. The rule of thumb is : A slope that is flat enough to hold snow but steep enough to ski has the potential to generate an avalanche, regardless of the angle. Additionally, avalanche risk increases with use; that is , the more a slope is distu
11、rbed by skiers, thd more likely it is that an avalanche will occur.Due to the complexity of the subject, winter travelling in the backcountry is never 100% safe. Good avalanche safety is a continuous process, including route selection and examination of the snowpack, weather conditions, and human fa
12、ctors. Several well-known good habits can also reduce the risk. If local authorities issue avalanche risk reports, they should be considered and all warnings should be paid attention to. Never follow in the tracks of others without your own evaluations; snow conditions are almost certain to have cha
13、nged since they were made. Observe the terrain and note obvious avalanche paths where plants are missing or damaged. Avoid traveling below others who might trigger an avalanche.第三篇 Germs on BanknotesPeople in different countries use different types of money yuan in China, pesos in Mexico, pounds in
14、the United Kingdom, dollars in the United States, Australia and New Zealand. They may use different currencies, but these countries, and probably all countries, still have one thing in common1: Germs on the banknotes.Scientists have been studying the germs on money for well over2 100 years. At the t
15、urn of the 20th century, some researchers began to suspect that germs living on money could spread disease.Most studies of germy money have looked at the germs on the currency within one country. In a new study, Frank Vriesekoop3 and other researchers compared the germ populations found on bills of
16、different countries.Vriesekoop3 is a microbiologist at the University of Ballarat in Australia4. He led the study, which compared the germ populations found on money gathered from 10 nations. The scientists studied 1,280 banknotes in total; all came from places where people buy food, like supermarke
17、ts street vendors and cafes, because those businesses often rely on cash.Overall, the Australian dollars hosted the fewest live bacteria - no more than 10 per square centimeter. Chinese yuan had the most - about 100 per square centimeter. Most of the germs on money probably would not cause harm.What
18、 we call “paper” money usually isnt made from paper. The U. S. dollar, for example, is printed on fabric that is mostly cotton .Different countries may use different materials to print their money. Some of the currencies studied by Vriesekoop and his team such as the American dollar were made from c
19、otton. Others were made from polymers.The three currencies with the lowest numbers of bacteria were all printed on polymers. They included the Australian dollar, the New Zealand dollar and some Mexican pesos. The other currencies were printed on fabric made mostly of cotton. Fewer germs lived on the
20、 polymer notes. This connection suggests that germs have a harder time staying alive on polymer surfaces. Scientists need to do more studies to understand how germs live on money-and whether or not we need to be concerned. Vnesekoop is now starting a study that will compare the amounts of time bacte
21、ria can stay alive on different types of bills.Whatever Vriesekoop finds, the fact remains: Paper money harbors germs We should wash our hands after touching it; after all5, you never know where your money s been. Or whats living on it+第四篇 Animals “Sixth Sense”(動(dòng)物的”第六感”)A tsunami was triggered by an
22、 earthquake in the Indian Ocean in December, 2004. It killed tens of thousands of people in Asia and East Africa. Wild animals, however, seem to have escaped that terrible tsunami. This phenomenon adds weight to notions that they possess a “sixth sense” for disasters, experts said.Sri Lankan wildlif
23、e officials have said the giant waves that killed over 24000 people along the Indian Ocean islands coast clearly missed wild beasts, with no dead animals found.“No elephants are dead, not even a dead rabbit. I think animals can sense disaster. They have a sixth sense. They know when things are happe
24、ning,” H.D. Ratnayake, deputy director of Sri Lankas Wildlife Department, said about one month after the tsunami attack. The waves washed floodwaters up to 2 miles inland at Yala National Park in the ravaged southeast, Sri Lankas biggest wildlife reserve and home to hundreds of wild elephants and se
25、veral leopards.“There has been a lot of apparent evidence about dogs barking or birds migrating before volcanic eruptions or earthquakes. But it has not been proven,” said Matthew van lierop, an animal behavior specialist at Johannesburg Zoo.“There have been no specific studies because you cant real
26、ly test it in a lab or field setting,” he told Reuters. Other authorities concurred with this assessment.“Wildlife seem to be able to pick up certain phenomenon, especially birds there are many reports of birds detecting impending disasters,” said Clive Walker, who has written several books on Afric
27、an wildlife.Animals certainly rely on the known senses such as smell or hearing to avoid danger such as predators.The notion of an animal “sixth sense” or some other mythical power is an enduring one which the evidence on Sri Lankas ravaged coast is likely to add to.The Romans saw owls as omens of i
28、mpending disaster and many ancient cultures viewed elephants as sacred animals endowed with special powers or attributes.+第五篇 Singing Alarms Could Save the Blind(警報(bào)器救盲人)If you cannot see, you may not be able to find your way out of a burning building and that could be fatal. A company in Leeds could
29、 change all that with directional sound alarms capalbe of guiding you to the exit.Sound Alert, a company run by the University of Leeds, is installing the alarms in a residential home for blind people in Sommerset and a resource centre for the blind in Cumbria. The alarms produce a wide range of fre
30、quencies that enable the brain to determine where the sound is coming from.Deborah Withington of Sound Alert says that the alarms use most of the frequencies that can be heard by humans. “It is a burst of white noise that people say sounds like static on the radio,” she says. “Its life-saving potent
31、ial is great.”She conducted an experiment in which people were filmed by thermal-imaging cameras trying to find their way out of a large smoke-filled room. It took them nearly four minutes to find the door without a sound alarm, but only 15 seconds with one.Withington studies how the brain processes
32、 sounds at the university. She says that the source of a wide band of frequencies can be pinpointed more easily than the source of a narrow band. Alarms based on the same concept have already been installed on emergency vehicles.The alarms will also include rising or falling frequencies to indicate
33、whether people should go up or down stairs. They were developed with the aid of a large grant from British Nuclear Fuels.+第六篇 Car Thieves Could Be Stopped Remotely(遠(yuǎn)程制止偷車賊)Speeding off in a stolen car, the thief thinks he has got a great catch. But he is in a nasty surprise. The car is fitted with a
34、 remote immobilizer, and a radio signal from a control center miles away will ensure that once the thief switches the engine off, he will not be able to start it again.For now, such devices are only available for fleets of trucks and specialist vehicles used on construction sites. But remote immobil
35、ization technology could soon start to trickle down to ordinary cars, and should be available to ordinary cars in the UK in two months.The idea goes like this. A control box fitted to the car incorporates a miniature cellphone, a microprocessor and memory, and a GPS satellite positioning receiver. I
36、f the car is stolen, a coded cellphone signal will tell the unit to block the vehicles engine management system and prevent the engine being restarted.There are even plans for immobilizers that shut down vehicles on the move, though there are fears over the safety implications of such a system.In th
37、e UK, an array of technical fixes is already making life harder for car thieves. “The pattern of vehicles crime has changed,” says Martyn Rand all of Thatcham, a security research organization based in Berkshire that is funded in part by the motor insurance industry.He says it would only take him a
38、few minutes to teach a novice how to steal a car, using a bare minimum of tools. But only if the car is more than 10 years old.Modern cars are a far tougher proposition, as their engine management computer will not allow them to start unless they receive a unique ID code beamed out by the ignition k
39、ey. In the UK, technologies like this have helped achieve a 31 per cent drop in vehicle-related crime since 1997.But determined criminals are still managing to find other ways to steal cars. Often by getting hold of the owners keys in a burglary. In 2000, 12 per cent of vehicles stolen in the UK wer
40、e taken by using the owners keys, which doubles the previous years figure.Remote-controlled immobilization system would put a major new obstacle in the criminals way by making such thefts pointless. A group that includes Thatcham, the police, insurance companies and security technology firms have de
41、veloped standards for a system that could go on the market sooner than the customer expects.+第七篇 An Intelligent Car(智能汽車)Driving needs sharp eyes, keen ears, quick brain, and coordination between hands and the brain. Many human drivers have all these and can control a fast-moving car. But how does a
42、n intelligent car control itself?There is a virtual driver in the smart car. This virtual driver has “eyes”, “brains”, “hands” and “feet”, too. The minicameras on each side of the car are his “eyes”, which observe the road conditions ahead of it. They watch the traffic to the cars left and right. Th
43、ere is also a highly automatic driving system in the car. It is the built-in computer, which is the virtual drivers “brain”. His “brain” calculates the speeds of other moving cars near it and analyzes their positions. Basing on this information, it chooses the right path for the intelligent car, and
44、 gives instructions to the “hands” and “feet” to act accordingly. In this way, the virtual driver controls his car.What is the virtual drivers best advantage? He reacts quickly. The minicameras are sending images continuously to the “brain.” It completes the processing of the images within 100 milli
45、seconds. However, the worlds best driver at least needs one second to react. Besides, when he takes action, he needs one more second.The virtual driver is really wonderful. He can reduce the accident rate considerably on expressways. In this case, can we let him have the wheel at any time and in amy
46、 place? Experts warn that we cannot do that just yet. His ability to recognize things is still limited . He can now only drive an intelligent car on expressways.+第八篇 A Biological Clock(生物鐘)Every living thing has what scientists call a biological clock that controls behavior. The biological clock tel
47、ls plants when to form flowers and when the flowers should open. It tells insects when to leave the protective cocoons and fly away, and it tells animals and human beings when to eat, sleep and wake.Events outside the plant and animal affect the actions of some biological clocks. Scientists recently
48、 found, for example, that a tiny animal changes the color of its fur because of the number of hours of daylight. In the short days of winter, its fur becomes white. The fur becomes gray brown in color in the longer hours of daylight in summer.Inner signals control other biological clocks. German sci
49、entists found that some kind of internal clock seems to order birds to begin their long migration flight twice each year. Birds prevented from flying become restless when it is time for the trip, but they become calm again when the time of the flight has ended.Scientists say they are beginning to le
50、arn which parts of the brain contain biological clocks. An American researcher, Martin Moorhead, said a small group of cells near the front of the brain seems to control the timing of some of our actions. These cells tell a person when to awaken , when to sleep and when to seek food. Scientists say
51、there probably are other biological clock cells that control other body activities.Dr. Moorhead is studying how our biological clocks affect the way we do our work. For example, most of us have great difficulty if we must often change to different work hours.It can take many days for a human body to
52、 accept the major change in work hours. Dr. Moorhead said industrial officials should have a better understanding of biological clocks and how they affect workers. He said such understanding could cut sickness and accidents at work and would help increase a factorys production.+第九篇 Wonder Webs(奇妙的網(wǎng))
53、Spider webs are more than homes, and they are ingenious traps. And the worlds best web spinner may be the Golden Orb Weaver spider. The female Orb Weaver spins a web of fibers thin enough to be invisible to insect prey, yet tough enough to snare a flying bird without breaking.The secret of the webs
54、strength? A type of super-resilient silk called dragline. When the female spider is ready to weave the webs spokes and frame, she uses her legs to draw the airy thread out through a hollow nozzle in her belly. Dragline is not sticky, so the spider can race back and forth along it to spin the webs tr
55、ademark spiral.Unlike some spiders that weave a new web every day, a Golden Orb Weaver reuses her handiwork until it falls apart, sometimes not for two years. The silky thread is five times stronger than steel by weight and absorbs the force of an impact three times better than Kevlar, a high-streng
56、th human-made material used in bullet-proof vests. And thanks to its high tensile strength, or the ability to resist breaking under the pulling force called tension, a single strand can stretch up to 40 percent longer than its original length and snap back as well as new. No human-made fiber even co
57、mes close.It is no wonder manufacturers are clamoring for spider silk. In the consumer pipeline: high-performance fabrics for athletes and stockings that never run. Think parachute cords and suspension bridge cables. A steady supply of spider silk would be worth billions of dollars but how to produc
58、e it? Harvesting silk on spider farms does not work because the territorial arthropods have a tendency to devour their neighbors.Now, scientists at the biotechnology company Nexia are spinning artificial silk modeled after Golden Orb dragline. The first step: extract silk-making genes from the spide
59、rs. Next, implant the genes into goat egg cells. The nanny goats that grow from the eggs secrete dragline silk proteins in their milk. “The young goats pass on the silk-making gene without any help from us,” says Nexia president Jeffrey Turner. Nexia is still perfecting the spinning process, but they hope artificial s
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