Captain Cook Arrow Legend C级
2009年理工新书 (蓝色标题为09年新增文章)
第六部分 完形填空
第一篇：
Captain Cook Arrow Legend（C级）
It was a great legend while it lasted, but DNA testing has finallyended a two-century-old story of the Hawiian arrow 箭头carved from the bone of British explorer Captain James Cook whodied in the Sandwich Islands1 in 1779.
“There is no Cook2 in the Australian Museum,” museum collection manager Jude Philip said not long ago in announcing the DNA evidence that the arrow was not made of Cook’s bone. But that will not stop the museum from continuing to display the arrow in its exhibition, “Uncovered: Treasures of the Australian Museum3,” which does include a feather cape presented to Cook by Hawaiian King Kalani’opu’u in 1778.
Cook was one of Britain’s great explorers and is credited with discovering the “Great South Land,” now Australia, in 1770. He was clubbed棍打to death in the Sandwich Islands, now Hawaii.夏威夷, 夏威夷岛
The legend of Cook’s arrow began in 1824 when Hawaiian King Kamehameha on his deathbed临死所卧之床, 临终之时gave the arrow to William Adams, a London surgeon and relative of Cook’s wife, saying it was made of Cook’s bone after the fatal fight with islanders.
In the 1890s the arrow was given to the AustralianMuseum and the legend continued until it came face-to-face with science.
DNA testing by laboratories in Australia and New Zealand revealed the arrow was not made of Cook’s bone but was more likely made of animal bone, said Philp.
However, Cook’s 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 say there is evidence not all of Cook’s body wasburied at sea in 1779. “On this occasion technology has won,4” 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 one day.”
第二篇：
Avalanche and Its Safety(C级)
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, typically snowpack, that is too massive and unstable for the slope that supports it. Determining the critical load, the amount of over-burden which is likelyto cause an avalanche, isa complex task involving the evaluation of a number of factors.
Terrain slopes flatter than 25 degrees or steeper than 60 degrees 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 snow’s angle of rest is between 35 and 45 degrees; the critical angle, the angle at which the human incidence of avalanches is greatest, is 38 degree. 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 disturbed by skiers, the more likely it is that an avalanche will occur.
Due to the complexity of the subject, winter traveling 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 factors. 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 changed 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：
One Good Reason to Let Smallpox Live（C级）
卫生第三篇
It’s now affair bet that we will never see the total extinction of the smallpox virus. The idea was to cap the glorious achievement of 1980, when smallpox was eradicated in the wild, by destroying the killer virus in the last two labs the are supposed to have it—one in the US and one in Russia. If smallpox had truly gone from the planet, what point was there in keeping these reserves?
In reality, of course, it was naïve to imagine that everyone would let go of such a potent potential weapon.1 Undoubtedly several nations still have a few vials. And the last “official” stocks of live virus bred mistrust of the US and Russia,2for no obvious gain.
Now American researchers have found an animal model of the human disease, opening the way for tests on new treatments and vaccines. So once again there’s a good reason tokeep the virus—just in case the disease puts in a reappearance.
How do we deal with the mistrust of the US and Russia? Simple. Keep the virus under international auspices in a well-guarded UN laboratory that’s open to all countries. The US will object, of course, just at it rejects a multilateral approach to just about everything. But it doesn’t mean the idea is wrong. If the virus is useful, then let’s make it the servant of all humanity—not just a part of it.
第四篇：
Animal’s “Sixth Sense”（C级）
A tsunami was triggered by an 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 I they possess a “sixth sense” for disasters , experts said.
Sri Lankan wildlife officials have said the giant waves that killed over 24,000 people along the Indian Ocean island’s 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 happening.” H.D. Ratnayake, deputy director of Sri Lanka’s Wildlife Department, said about one month after the tsunami attack. The waves washed floodwaters up to 2 miles inland at YalaNational Park in the ravaged southeast, Sri Lanka’s biggest wildlife reserve and home to hundreds of wild elephants and several 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 behaviorspecialist at Johannesburg Zoo.
“There have been no specific studies because you can’t really test it in a lab or field setting2,” 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 African 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”-orsome other mythical power-is an enduring one3 which the evidence on Sri Lanka’s ravaged coast is likely to add to.
The Romans saw owls asomens of impending 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（C级）
If you cannot see, you may not be able to1 find your way out of a burning building—and that could be fatal. A company in Leeds could change all that2with directional sound alarms capable of guiding you to the exit.
Sound Alert, a companyrun bythe University of Leeds, is installing the alarms in a residential home for blind people in Sommerset and a resource center for the blind in Cumbria.The alarms produce a wide range of frequencies 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 beheard by humans. “It is a burst of white noise白噪音：音响或电力嗓音thatpeople say sounds like static静电噪声on the radio,” she says. “Its life-saving potential is great.”
She conducted an experiment in which people were filmed by thermal-imaging cameras trying to find their way out of3 a large smoke-filled room. Ittook them nearly four minutesto find the doorwithout a sound alarm, but only 15 seconds with one.
Withington studies how the brain processes sounds at the university. She says that the source of a wide band 波段of frequencies can be pinpointed 极微小的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 whether people should go upor 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遥远地（C级）
Speeding off超速行驶in a stolen car, the thief thinks he has got a great catch2. But he is in a nasty3 surprise. The car is fitted with a remote immobilizer, and a radio signal from a control center miles away will ensure that once the thief switches the engineoff , he will not be able to start it again.
For now, such devicesare only available for fleets of trucks4 and specialist vehicles used on construction sites. But remote immobilization technology could soon start to trickle慢慢地移动down to ordinary cars,5 andshould be available to ordinary cars in the UKin two months.
The idea goes like this. A control box fitted to the car incorporates6a miniature cellphone, a microprocessor and memory, and a GPS7 satellite positioning receiver. If the car is stolen, a coded cellphone signal will tell the unit to block the vehicle’s engine management system and prevent the engine being restarted.
There are even plans for immobilizers that shut down vehicles on the move8, though there are fears over the safety implications of such a system.
In the UK, an array of9 technical fixes10 is already makinglifeharder for car thieves. “The pattern of vehicles crime has changed,” says Martyn Randall of Thatcham, a security research organization based in Berkshire11 that is funded in part by the motor insurance industry.
He says it would only take him a few minutes to teach a novice新手, 初学者how to steal a car using a bare minimum of tools12. But only if the car is more than 10 years old.
Modern cars are a far tougher艰苦的proposition任务：13, as their engine management computer will not allow themto start unless they receive a unique ID code beamed out 14 by the ignition key. In the UK, technologies like this have helped achieve a 31 per cent drop in vehicle-related crime15since 1997.
But determined criminals are still managing to find other ways to steal cars. Often by getting hold of the owner’s keys in a burglary. In 2000, 12 per cent of vehicles stolen in the UK were taken using the owner’s keys double the previous year’s figure.
Remote-controlled immobilization system would put打断a major new obstacle in the criminal’s way by making such thefts pointless. A group that includes Thatcham, the police, insurance companies and security technology firms have developed standards for a system that could go on the market sooner than the customer expects.
第七篇
An Intelligent Car（C级）
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 an intelligent car control itself?
There is a virtual drive1 in the smart car. This virtual driver1 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 thetraffic to the car’s left and right. There is also a highlyautomatic driving system in the car. It is the built-in computer, which is the virtual driver’s “brain.” His “brain” calculates the speeds of other moving cars near it and analyzes their positions. Basing on this information2, it chooses the right path for the intelligent car, and gives instructions to the “hands” and “feet” to act accordingly. In this way, the virtual driver controls his car.
What is the virtual driver’s best advantage3? He reacts quickly. The minicameras are sending images continuously to the “brain.” It completes the processing of the images within 100 milliseconds. However, the world’s 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 accidentrate considerably on expressways. In this case, can we let him have the wheel4 at any time and in any place? Experts warn what we cannot do that5 just yet6. His ability to recognize things is still limited . He can now only drive an intelligent car on expressways.
第八篇：
A Biological Clock（C级）
Every living thing has what scientists call a biological clock that controls behavior. The biological clock tells plants when to form flowers and when the flowers should open1. It tells insects when to leave the protective cocoon茧and fly away, and it tells animals and human beings when to eat, sleep and wake.
Events outside the plant and animal affect 影响the actions of some biological clocks. Scientists recently found, for example, that a tiny animal changes the color of its furbecause of the number of hours of daylight. In the shortdays of winter, its fur becomes white. The fur becomes gray brown in color in the longer hours of daylight summer.
Inner signals control other biological clocks. German scientists found that some kind of internal clock seems to order birds to begin their long migration flight twice each year. Birds prevented from阻止, 妨碍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 learn whichparts of the brain contain biological clocks. An American researcher, Martin Moorhead, said a small group of cells near the front of the brainseemsto control the timing of some of our actions. These cells tell a person when toawaken , when to sleep and when to seek food. Scientists say 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 work2. For example, most of us have great difficulty if we must often change to different work hours. It can take3 many days for a human body to 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 factory’s production.
第九篇：
Wonder Webs（C级）
Spider webs are more than homes, and they are ingenious traps. And the world’s best web spinner may be the Goldern Orb Weaver spider. The female Orb Weaver spins a web of fibers thin enough to be invisible to insect prêt, yet tough enough to snare a flying bird without breaking.
The secret of the web’s strength? A type of super-resilient silk called dragline. When the female spider is ready to weave the web’s 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 web’s trademark 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 years1. 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-strength 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 comes close .
It is nowonder manufacturers are clamoring for spider silk. In the consumer pipeline: high-performance fabrics for athletes and stockings that never run2. Think parachute cords and suspension bridge cables. A steady supply of spider silk would be worth billions of dollars—but how to produce 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 Goldern Orb dragline. Thefirst step: extract silk-making genes from the spiders. 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 withoutany help from us,” says Nexia president Jeffrey Turner. Nexia is still perfecting the spinning process, but they hope artificial spider silk will soon be snagging customers as fast as the real thing snags bugs.
第十篇：
Less Is More（C级）
It sounds all wrong—drilling holes in a piece of wood to make it more resistant to knocks. But it works because the energy from the blow gets distributed throughout the wood rather than focusing on one weak spot. The discovery should lead to more effective and ligher packaging materials.