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Animals Sixth Sense A tsunami was triggered by an earthquake in the Indian Ocean in December, 2004. It killedtens of thousands of people in Asia and East Africa. Wild animals, 1however , seem to have escaped that terrible tsunami. This phenomenon adds weight to notions that they possess a sixth sense for 2disasters , experts said. . Sri Lenkan wildlife officials have said the giant waves that killed over 24,000 people along the Indian Ocean islands coast clearly 3missed wild beasts, with no dead animals found. No elephants are dead, not 4even a dead rabbit. I think animals can 5sense discster. They have a sixth sense. They know when things are happening, H. D. Ratuayake, deputy director of Sri Lankas Wildlife Department, said about me month after the tsunami attack, The 6waves washed floodwaters up to 2 miles inland at Yala National park in the. ravaged southeast, Sri Lankas biggest wildlife 7reserve and home to hundreds of wild elephants and several leopaids. There has been a lot of 8apparent evidence about dogs barking or birds migrating before volcanic eruptions or earthquakes. But it has not been proven, said Matthew, van Liemp, an animal behavior 9specialist at Johannesburg Zoo. There have been no. 10specific studies because you cant really test it in a lab or field netting, he told Reuters. Other authorities concurred with this 11assessment Wildlife seem to be able to pick up certain 12phenomenon , especially birds . there are many reports of birds detecting impending disasters, said dive Walker, who has written several books on African wildlife. Animals 13certainly rely. on the known senses such as smell or hearing to avoid danger such as predators. The notion of an animal sixth sense - or 14some other mythical power - is an enduring onewhich the evidence on Sri Iankas ravaged coast is likely to add to. The Romans saw owls 15as omens of impending disaster and many ancient cultures viewed elephants as sacred animals endowed with special powers or attributes.Singing Alarms Could Save the Blind 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 Lecds could change all tiat . 1with directional sound alarms capable of guiding you to the exit. Sound Alert, a company 2run by the University of Leeds, is installing the alarms in a maidential home for 3blind people in.Sommerset and a resource centre for the blind in Cumbria.4the alarms produce a wide range of frequencies that enable. the brain to determine where the5sound is coming from. Deborah W ithington of Sound Alert says that the alarms use most of the frequencies that can be 6heard by humans. It is a burst of white noise 7that 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 8smoke-filled room. It 9took them nearly four minutes to find the door 10without a wood alarm, but omy 15 seconds with one. Withington studies how the brain 11peocesses sounds at the university. She says that the 12source of a wide band of frequencies can be pinpointed more easily than the source of a narrow band. Alarms 13based on the same concept have already been installed on. emergency vehicles. The alarms will also include rising -orfalling frequencies to indicate whether people should go up 14or down stairs. They were 15developed with the aid of a large grant from British Nuclear Fuels.Car Thieves Could Be Stopped RemotelySpeeding off ins 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 immobilizes, and a radio signal from a control center miles away will ensure that once the thief switches the, engine 1off , he will not be able to start it again.For now, such devices 2are only available for fleets of trucks and specialist vehicles used on construction sites. But remom immobilization technology could soon start to trickle down to ordinary cars, and . 3should be available to ordinary cars in the UK 4in_two months.The idea goes tike this. A control box fitted to the car incorporates 5a miniature cellphone, a microprocessor and memory, and a GPS satellite positioning receiver. 6if the car is stolen, a coded cellphone signal will tell the unit to block the vehicles engine management system and prevent the engine 7being restarted.There are even plans for immobihzers 8that shut down vehicles on the move, thoughthere are few over the safety implications of such a system.In the UK, an army of technical fixes is already making 9life harder for car thieves.The pattern of vehicles crime has changed, says Martyr Randall of Thatcham; a -security research organization based in Berkshire that is funded in part 10by the motor msumnce industry.He says it would only take him a few minutes to 11teach a novice how to stal a car, using a bare minimum of tools, But only if the car is: mom than 10 yew old.Modem cars are a far tougher. proposition, as their engine management computer will not 12allow them to start unless they receive a unique ID code beamed out by the ignition key. In the UK, technologies Re this. 13have helped achieve . a 31 per cent drop in vehicle-related crimesince 1997.But determined criminals are still managing to find other ways to steal cars. .Often by gettinghold of the owners keys. in a burglary. In 2000. 12 per cent of vehicles stolen in the UK weretaken by using. the owners keys, which doubles the previous years figure.Remote-controlled immobilimtion system would 14put a majornewobstacle in thecriminals way by making such thefts pointless. A group that in-eludes thatcham, the police, insurance companies and security technology firms have developed standards for a system that could go on the market sooner than the 15customer expects.A Biological Clock Every living thing has what scientists call a biological clock that controls behavior. The bluing.ical clock tells 1plants when to form flowers and when the flowers should open. It tells 2insects when to leave the protective cocoons and fly away, arid it tells animals and human beings where m eat, sleep and wake: Events outside the plant and animal 3affect the actions of some biological clocks. Sciedtists tecently.found, for example; that a tiny animal changes the color of its fur 4because of the number of hours of daylight. In the short 5days 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 scientists found that some kind of internal clock seems to order birds to begin their long migration 6flight twice. each year. Birds 7prevented from . flying become restless when it is time for the trip, 8but they become can agsitiwhen the time of the (light has ended. Scientists say they are beginning m learn which 9portions of the brain contain biological clocks. An American researcher, Martin Moorbead, said a small group of cells near the front of the brain 10seems to control the timing of some of our actions. These . -11cells tell a person when to 12awaken , 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 13how our biological clocks affect the way we do our works. For example, most of us have great difficulty. if we must often change to different work hours. 14it can take many days for a human body to accept the major change in work hours.Dr.Moothead said industrial officials should have a better understanding of biological clocks end how they affect workers. He said 15such understanding could cut sickness and accidents at work and. would help increase a factorys production.Wonder Webs Spider webs are more than homes, and they are ingenious traps. And the worlds best web spinier 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 1tough enough to snare a flying bird without breaking. The secret of the webs strength? A type of super-resilient 2silk celled drag8ne. When the female spider is ready m 3weave the webs spokes and frame, she uses her legs to draw the wiry thread out through a hollow nozzle in ber belly. Ihagline is not sticky, so the spider can race back and forth along 4it m spin the webs trademark spiral. Unlike some spiders that weave a new web every day, a Golden Orb Weaver 5reuses 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 6material 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 7length and snapback as well as new. No human-made fiber even comes 8close It is no 9wonder manufacturers are clamoring for spider silk. In the consumer pipeline; highperformance fabrics for athletes and stockings that never ran: Think parachute cords and suspension bridge cables. A steady 10supply of spider silk would be worth billions of dollars but how to produce it? Harvesting silk on spider farms does not 11work 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 12first 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 sills proteins in their 13milk . The young goats pass on. the silk-making gene without 14any help from us, says Nexiapresident Jeffrey Tutner.-Nexia is still perfecting the spinning procoss, but they hope artificial spider silk will soon be snagging customers 15as fast as the real thing snags bugs.China to Help Europe Develop GPS RivalChina is to contribute to a new global satellite navigation system being developed by European nations: The Galileo satellite system 1will offer a more accurate civilian afemative to the Global Positioning,Systern (GPS), operated by the US military. China will provide 230m Emos (USD 259m)4in 2funding and will cooperate with technical, manufacturing and market development China will help Galileo to 3become the major world infrastructure for the growing market for location services, said Loyola de Palacio, EU transport commissioner. A new center that will coordinate co-operation was also amrounced 4by the European Commission, the European Space Agency (ESA) and the Chinese Ministry of Science and Technology not long 5ago.The China-Europe Global Navigation Satellite System Technical Training and Cooperation Center will be 6located at Beijing. University. China has a substantial satellite launch industry and could potentially help launch the Galileo satellites.The US has claimed that Galileo could interfere 7with the US ability to downgrade the GPS service during military conflicts. European officials say this is unfounded and counter that US opposition 8is due to the commercial challenge Galileo would present to GPS. Galileo will be precise to within a meter, while the civilian GPS service is accurate to mound 10 meters.The Galileo satellite constellation will 9consist of 27 operational and three reserve satellites orbiting the. Earth at an altitude of 23,600 km.The satellites will be acreage along three medium-Earth orbits at 56 degrees inclination to the equator and will provide global coverage. The system should be operational by 2008 and the entire project is expected to 10 cost around 3. 2 billion Emos(USD 3.6 billion).The European Commission has said Galileo will primarily be used for transportation technology, scientific rosearch, land management and disaster monitoring.Galileo will provide two signals; a standard civilian one and an encrypted, wide-band signal 11called the Public Regulated Service (PRS). This second signal is designed m withstand localized jamming and will be used by. police and military services N Europe. European Commission 12officials have said China will not be given access to the PRS.The first Galileo satellite is scheduled to launch late in 2004. Clocks on board 13the satellite will be synchronized through 20 ground sensors stations, two command centers and 15 uplink stations.Receiver on the ground will use time signals from the satellites to precisely calculate their 14location . A search and rescue function will also- 15let distress signals be relayed through the constellation of satellites.Captain Cook Arrow LegendIt was a great legend while it lasted, but DNA testing has 1finally ended a two-century-old story of the Hawaiian arrow carved from the bone of British, explorer Captain James Cook 2who died in the Sandwich Islands in 1779.There is 3no 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 mow in its 4exhibition ，Uncovered: Treasures of the. Australian Museum,”which 5does include a feather, cape presented to Cook by Hawaiian King Kalaniopuu in 1778.Cook was one of Britains great explorers and is credited with 6exhibition the“Great South Land，7now Australia，in 1770. He was clubbed to death in the Sandwich Islands，now Hawaii.The legend of Cooks arrow began in 1824 8when Hawaiian King Kamebameha 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 9fight with islanders。In the 1890s the arrow was. given to -the Australian Museum and the legend continued 10until it came face-to-face with scienceDNA testing by laboratories in. Australia and New Zealand revealed the arrow was not made of Cooks bone but was 11likely made of animal bone, said Philp.However, Cooks fans 12refuse to give up hope that one Cook legend will prove true and that part of his remains will still be uncovered, as they say them is evidence not all of Cooks body was 13buried at sea in 1779.“On this occasion technology has won，”said Cliff Thornton， president of the Captain Cook Society，in a 14statement from Britain.“But I am 15sure that one of these days.one of the Cook legends will prove to be true and it will happen one day. Avalanche and Its SafetyAn avalanche is a sudden and rapid flow of snow, often mixed with air and water, down a mountainside. Avalanches are 1among 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 2that supports it. Determining the critical load, the amount of over-burden which is 3likely to cause an avalanche, 4is a complex task involving the e- valuation of a number of factors.Terrain slopes flatter than 25 degrees or steeper than 60 degrees typically have a low 5risk of avalanche. Snow does not 6gather significantly on steep slopes; also, snow does nut 7flow easily on flat slopes. Human-triggered avalanches have the greatest incidence when the snows angle of rest is 8between 35 and 45 degrees; the critical angle, the angle at which the human incidence of avalanches is greatest, is 38 degrees. The mle of thumb is; A slope that is 9flat 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 10use ; 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 travelling in the backcountry is never 100% safe.Good avalanche safety is a continuous 11process , including route selection and examination of the snowpack,.weather 12conditions , and human factors. Several well-known good habits can also 13reduce the risk. If local authorities issue avalanche risk reports, they should be considered and all warnings should be paid 14attention 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 15missing or damaged. Avoid traveling below others who might trigger an avalanche.Seeing red Means Danger Ahead The color red often means danger- and by paying attention, 1accident can be prevented.At railroad crossings, flashing red lights warn cars to stay back. A red light at a traffic intersection tells cars to atop, so 2they dont run into other cars. In the future, the color red also may help prevent danger 3at construction sites. Thanks to new work. by engineers, bridge supports- or other kinds of materials - could one day contain a color-changing material. It will turn red 4before a structure collapses or falls 5apart . A tiny molecule may make a big difference in future warning systems. A polymer 6containing a color-changing molecule called a mechanophore turns red seconds before.it snaps. The technology may one day allow damage to materials or structures to be easily 7spotted. The secret behind the color-changing material is a particular type of molecule. A molecule is a group of atoms held together by 8chemical bonds. Molecules come in all shapes. and sins, and make up 9everything you can see, touch or feel. How a molecule behaves depends on what kinds of atoms it contains, and how theyre held together. When a polymer containing a color-changing molecule called a mechanophore is about m break, it produces a color. When a polymer with mechanophore molecules becomes injured or 10weak , one of the mechanophore bonds breaks and the material turns red. Its a really simple detection method, says Nancy Sottos, one of the scientists who worked on the project. Were 11opening up this one bond, and it changes color. Sottos and her team tested the color changing polymers in their lab. The test 12results proved encouraging. There is a way to get rid of the red color: 13light . When a bright light is shone on the mechanophore, the broken bond is fined- and the red color disappears. This self-healing may be a problem for engineers. They need to use the color-changer in big construction pmjecis that will be 14outside , in sunlight. And sunlight will make the mechanophores warning system useless. Sotros and her fellow scientists still have 15a lot of work to do before the color-changing molecules can be used outside the lab.An Intelligent Car Driving needs sharp eyes, keen ears, quick brain, and coordination between hands and the brain. Many human drivers have all 1these 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 minicamems2on each side of the car are his eyes, which observe the mad condi
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