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第一篇第一篇captaincaptain cookcook arrowarrow legend(legend(库克船长弓箭的传说库克船长弓箭的传说) ) it was a great legend while it lasted, but dna testing has finallyfinally ended a two-century-old story of the hawaiian arrow carved from the bone of british explorer captain james cook whowho died in the sandwich islands in 1779. “there is nono cook 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 cooks bone. but that will not stop the museum from continuing to display the arrow in its exhibitionexhibition, “uncovered: treasures of the australian museum,” which doesdoes include a feather cape presented to cook by hawaiian king kalaniopuu in 1778. cook was one of britains great explorers and is credited with discoveringdiscovering the “great south land,” nownow australia, in 1770. he was clubbed to death in the sandwich islands, now hawaii. the legend of cooks arrow began in 1824 whenwhen hawaiian king 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 fightfight with islanders. in the 1890s the arrow was given to the australian museum and the legend continued untiluntil it came face-to-face with science. dna testing by laboratories in australia and new zealand revealed the arrow was not made of cooks bone but was more likelylikely made of animal bone, said philp. however, cooks fans refuserefuse 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 cooks body was buriedburied at sea in 1779. “on this occasion technology has won,” said cliff thornton, president of the captain cook society, in a statementstatement from britain. “but i am suresure that one of these days one of the cook legends will prove to be true and it will happen one day.” 第二篇第二篇avalancheavalanche andand itsits safety(safety(雪崩和安全问题雪崩和安全问题) ) an avalanche is a sudden and rapid flow of snow, often mixed with air and water, down a mountainside. avalanches are amongamong 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 thatthat supports it. determining the critical load, the amount of over-burden which is likelylikely to cause an avalanche, isis a complex task involving the evaluation of a numberof factors. terrain slopes flatter than 25 degrees or steeper than 60 degrees typically have a low riskrisk of avalanche. snow does not gathergather significantly on steep slopes; also, snow does not flowflow easily on flat slopes. human-triggered avalanches have the greatest incidence when the snows angle of rest is betweenbetween 35 and 45 degrees; the critical angle, the angle at which the human incidence of avalanches is greatest, is 38 degrees. the rule of thumb is : a slope that is flatflat 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 useuse; that is , the more a slope is disturbed 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 processprocess, including route selection and examination of the snowpack, weather conditionsconditions, and human factors. several well-known good habits can also reducereduce the risk. if local authorities issue avalanche risk reports, they should be considered and all warnings should be paid attentionattention to. never follow in the tracks of others without your own evaluations; snow conditions are almostcertain to have changed since they were made. observe theterrain and note obvious avalanche paths where plants are missingmissing or damaged. avoid traveling below others who might trigger an avalanche. 第四篇第四篇animalanimals s “sixthsixth sensesense”( (动物的动物的”第六感第六感”) ) 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, howeverhowever, seem to have escaped that terrible tsunami. this phenomenon adds weight to notions that they possess a “sixth sense” for disastersdisasters, experts said. sri lankan wildlife officials have said the giant waves that killed over 24000 people along the indian ocean islands coast clearly missedmissed wild beasts, with no dead animals found. “no elephants are dead, not eveneven a dead rabbit. i think animals can sensesense disaster. they have a sixth sense. they know when things are happening,” h.d. ratnayake, deputy director of sri lankas wildlife department, said about one month after the tsunami attack. the waveswaves washed floodwaters up to 2 miles inland at yala national park in the ravaged southeast, sri lankas biggest wildlife reservereserve and home to hundreds of wild elephants and several leopards. “there has been a lot of apparentapparent 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 specialistspecialist at johannesburg zoo. “there have been no specificspecific studies because you cant really test it in a lab or field setting,” he told reuters. other authorities concurred with this assessmentassessment. “wildlife seem to be able to pick up certain phenomenonphenomenon, especially birds there are many reports of birds detecting impending disasters,” said clive walker, who has written several books on african wildlife. animals certainlycertainly rely on the known senses such as smell or hearing to avoid danger such as predators. the notion of an animal “sixth sense” or somesome other mythical power is an enduring one which the evidence on sri lankas ravaged coast is likely to add to. the romans saw owls asas omens of impending disaster and many ancient cultures viewed elephants as sacred animals endowed with special powers or attributes. 第五篇第五篇singingsinging alarmsalarms couldcould savesave thethe blind(blind(警报器救盲人警报器救盲人) ) 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 change all that withwith directional sound alarms capalbe of guiding you to the exit. sound alert, a company runrun byby the university of leeds, is installing the alarms in a residential home for blindblind people in sommerset and a resource centre for the blind in cumbria. thethe alarmsalarms produce a wide range of frequencies that enable the brain to determine where the soundsound is coming from. deborah withington of sound alert says that the alarms use most of the frequencies that can be heardheard by humans. “it is a burst of white noise thatthat people say sounds like static 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 of a large smoke-filledsmoke-filled room. it tooktook them nearly four minutes to find the door withoutwithout a sound alarm, but only 15 seconds with one. withington studies how the brain processesprocesses sounds at the university. she says that the sourcesource of a wide band of frequencies can be pinpointed more easily than the source of a narrow band. alarms basedbased onon 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 up oror down stairs. they were developeddeveloped with the aid of a large grant from british nuclear fuels. 第六篇第六篇carcar thievesthieves couldcould bebe stoppedstopped remotely(remotely(远程制止偷车贼远程制止偷车贼) ) 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 remote immobilizer, and a radio signal from a control center miles away will ensure that once the thief switches the engine offoff, he will not be able to start it again. for now, such devices areare only available for fleets of trucks and specialist vehicles used on construction sites. but remote immobilization technology could soon start to trickle down to ordinary cars, and shouldshould be available to ordinary cars in the uk inin two months. the idea goes like this. a control box fitted to the car incorporates a a miniature cellphone, a microprocessor and memory, and a gps satellite positioning receiver. ifif the car is stolen, a coded cellphone signal will tell the unit to block the vehicles engine management system and prevent the engine beingbeing restarted. there are even plans for immobilizers thatthat shut down vehicles on the move, though there are fears over the safety implications of such a system. in the uk, an array of technical fixes is already making lifelife 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 byby the motor insurance industry. he says it would only take him a few minutes to teachteach 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 allowallow them to start unless they receive a unique id code beamed out by the ignition key. in the uk, technologies like this havehave helpedhelped 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 were taken by using the owners keys, which doubles the previous years figure. remote-controlled immobilization system would putput 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 developed standards for a system that could go on the market sooner than the customercustomer expects. 第七篇第七篇anan intelligentintelligent car(car(智能汽车智能汽车) ) driving needs sharp eyes, keen ears, quick brain, and coordination between hands and the brain. many human drivers have all thesethese and can control a fast-moving car. but how does an 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 onon each side of the car are his “eyes”, which observe the road conditions ahead of it. they watch the traffictraffic to the cars left and right. there is also a highly automaticautomatic driving system in the car. it is the built-in computer, which is the virtual drivers “brain”. his “brain” calculates the speeds of otherother moving cars near it and analyzes their positions. basing on this information, it chooses the right pathpath for the intelligent car, and gives instructionsinstructions 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 quicklyquickly. the minicameras are sendingsending images continuously to the “brain.” it completescompletes the processing of the images within 100 milliseconds. however, the worlds best driver atat leastleast needs one second to react. besidesbesides, when he takes action, he needs one more second. the virtual driver is really wonderful. he can reduce the accident raterate considerably on expressways. in this case, can we let him have the wheel at any time and in amy place? experts warnwarn that we cannot do that just yet. his ability to recognize things is still limitedlimited . he can now only drive an intelligent car on expressways. 第九篇第九篇wonderwonder webs(webs(奇妙的网奇妙的网) ) 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 toughtough enough to snare a flying bird without breaking. the secret of the webs strength? a type of super-resilient silksilk called dragline. when the female spider is ready to weaveweave 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 itit to spin the webs trademark spiral. unlike some spiders that weave a new web every day, a golden orb weaver reusesreuses 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-strength human-made materialmaterial 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 lengthlength and snap back as well as new. no human-made fiber even comes closeclose. it is no wonderwonder 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 supplysupply of spider silk would be worth billions of dollars but how to produce it? harvesting silk on spider farms does not workwork 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 firstfirst 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 milkmilk. “the young goats pass on the silk-making gene without anyany 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 asas fastfast asas the real thing snags bugs. 第十篇第十篇chickenchicken soupsoup forfor thethe soul:comfortsoul:comfort foodfood fightsfights lnelinesslneliness(心灵鸡汤:爽心食品(心灵鸡汤:爽心食品 排解孤独感)排解孤独感) mashed potatoes, macaroni and cheese, may be bad for your arteries, butbut according to a study in psychological science, theyre good for your heart and emotionsemotions the study focuses on “comfort food” and how it makes people feel “for me p personallyersonally ,food has always played a big role in my family,” says jordan troisi, a graduate student at the university of buffalo, and lead author on the study thestudy cameoutoftheresearch programof hiscoauthorshira gabrielit has lookedlooked atat non-human things that may affect human emotionssome people reduce loneliness by bonding with thei
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