【正文】 outhwest spokeswoman for the PASPB, took part in the challenge as a schoolgirl. She said the society had no objections to the event itself but simply wanted it moved to another time of year. “It is a wonderful activity for the children who take part but, having thousands of people walking past in one weekend when birds are breeding is hardly ideal,” she said. “We would prefer it to take place after the breeding and nesting season is over. There is a risk of destruction and disturbance. If the walkers put a foot in the wrong place they can crush the eggs and if there is sufficient disturbance the birds might abandon the nest.” Helen Booker, an RSPB upland conservation officer, said there was no research into the scale of the damage but there was little doubt the walk was detrimental. “If people are tramping past continually it can harm the chances of successful nesting. There is also the fear of direct trampling of eggs.” A spokesman for the Dartmoor National Park Authority said the breeding season on the moor lasted from early March to midJuly, and the Ten Tors Challenge created the potential for disturbance for March, when participants start training. To move the event to the autumn was difficult because children would be on holiday during the training period. There was a possibility that some schools in the Southwest move to a fourterm year in 2004, “but until then any change was unlikely. The authority last surveyed bird life on Dartmoor two year ago and if the next survey showed any further decline, it would increase pressure to move the Challenge,” he said. Major Mike Pether, secretary of the army mittee that organises the Challenge, said the event could be moved if there was the popular will. “The Ten Tors has been running for 42 years and it has always been at this time of the year. It is almost in tablets of stone but that’s not to say we won’t consider moving if there is a consensus in favour. However, although the RSPB would like it moved, 75 per cent of the people who take part want it to stay as it is,” he said. Major Pether said the trek could not be moved to earlier in the year because it would conflict with the lambing season, most of the children were on holiday in the summer, and the winter weather was too harsh.Datmoor National Park occupies some 54 sq km of hills topped by granite outcrops known as “Tors” with the highest Torcapped hill reaching 621m. The valleys and dips between the hills are often sites of bogs to snare the unwary hiker. The moor has long been used by the British Army as a training and firing range. The origin of the event stretches back to 1959 when three Army officers exercising on the moor thought it would provide a challenge for civilians as well as soldiers. In the first year 203 youngsters took up the challenges. Since then teams, depending on age and ability, face hikes of 35, 45 or 55 miles between 10 nominated Tors over two days. They are expected to carry everything they need to survive.1. What is the Ten Tors Challenge? Give a brief introduction of its location and history.2. Why is it suggested that the event be moved to the autumn or other seasons?3. What are the difficulties if the event is moved to the autumn or other seasons?Questions 4～5 Mike and Adam Hurewitz grew up together on Long Island, in the suburbs of New York City. They were very close, even for brothers. So when Adam’s liver started failing, Mike offered to give him half of his. The operation saved Adam’s life. But Mike, who went into the hospital in seemingly excellent health, developed a plication—perhaps a blood colt—and died last week. He was 57. Mike Hurewitz’s death has prompted a lot of soul searching in the transplant munity. Was it a tragic fluke or a sign that transplant surgery has reached some kind of ethical limit? The Mount Sinai Medical Center, the New York City hospital where the plex double operation was performed, has put on hold its adult living donor liver transplant program, pending a review of Hurewitz’s death. Mount Sinai has performed about 100 such operations in the past three years. A 1in100 risk of dying may not seem like bad odds, but there’s more to this ethical dilemma than a simple ratio. The first and most sacred rule of medicine is to do no harm. “For a normal healthy person a mortality rate 1% is hard to justify,” says Dr. John Fung, chief of transplantation at the University of Pittsburgh Medical Center. “If the rate stays at 1%, it’s just not going to be accepted.” On the other hand, there’s an acute shortage of traditional donor organs from people who have died in accidents or suffered fatal heart attacks. If family members fully understand the risks and are willing to proceed, is there any reason to stand in their way? Indeed, a recent survey showed that most people will accept a mortality rate for living organ donors as high as 20%. The odds, thankfully, aren’t nearly that bad. For kidney donors, for example, the risk ranges from 1 in 2, 500 to 1 in 4, 000 for a healthy volunteer. That helps explain why nearly 40% of kidney transplants in the . e from living donors. The operation to transplant a liver, however, is a lot trickier than one to transplant a kidney. Not only is the liver packed with blood vessels, but it also makes lots of proteins that need to be produced in the right ratios for the body to survive. When organs from the recently deceased are used, the surgeon gets to pick which part of the donated liver looks the best and to take as much of it as needed. Assuming all goes well, a healthy liver can grow back whatever portion of the organ is missing, sometimes within a month. A livingdonor transplant works particularly well when an adult donates a modest portion of the liver to a child. Usually only the left lobe of the organ is required, leading to a mortality rate for livingdonors in the neighborhood of 1 in 500 to 1 in 1, 000. But when the recipient is another adult