题目内容
A New Finding
British cancer researchers have found that childhood leukaemia is caused by an infection and clusters of cases around industrial sites are the result of population mixing that increases exposure. The research published in the British Journal of Cancer backs up a 1988 theory that some as yet unidentified infection caused leukaemia—not the environmental factors widely blamed for the disease.
“Childhood leukaemia appears to be an unusual result of a common infection,” said Sir Richard Doll, an internationally—known cancer expert who first linked tobacco with lung cancer in 1950. “A virus is the most likely explanation. You would get an increased risk of it if you suddenly put a lot of people from large towns in a rural area, where you might have people who had not been exposed to the infection.” Doll was commenting on the new findings by researchers at Newcastle University, which focused on a cluster of leukaemia cases around the Sellafield nuclear reprocessing plant in Cumbria in northern England. Scientists have been trying to establish why there was more leukaemia in children around the Sellafield area, but have failed to establish a link with radiation or pollution. The Newcastle University research by Heather Dickinson and Louise Parker showed the cluster of cases could have been predicted because of the amount of population mixing going on in the area, as large numbers of construction workers and nuclear staff moved into a rural setting. “Our study shows that population mixing can account for the (Sellafield) leukaemia cluster and that all children, whether their parents are incomers or locals, are at a higher risk if they are born in an area of high population mixing,” Dickinson said in a statement issued by the Cancer Research Campaign, which publishes the British Journal of Cancer.
Their paper adds crucial weight to the 1988 theory put forward by Leo Kinlen, a cancer epidemiologist at Oxford University, who said that exposure to a common unidentified infection through population mixing resulted in the disease.
Who first hinted at the possible cause of childhood leukaemia by infection？______
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Problems of Internet
The proportion of works cut for the cinema in Britain dropped from 40 per cent when I joined the BBFC in 1975 to less than 4 per cent when I left. But I don’t think that 20 years from now it will be possible to regulate any medium as closely as I regulated film.
The Internet is, of course, the greatest problem for this century. The world will have to find a means, through some sort of international treaty of United Nations initiative, to control the material that’s now going totally unregulated into people’s homes. That said, it will only take one little country like Paraguay to refuse to sign a treaty for transmission to be unstoppable. Parental control is never going to be sufficient.
I’m still very worried about the impact of violent video games, even though researchers say their impact is moderated by the fact that players don’t so much experience the game as enjoy the technical manoeuvres (策略)that enable you to win. But in respect of violence in mainstream films, I’m more optimistic. Quite suddenly, tastes have changed, and it’s no longer Stallone or Schwarzenegger who are the top stars, but Leonardo DiCaprio—that has taken everybody by surprise.
Go through the most successful films in Europe and America now and you will find virtually none that we are violent. Quentin Tarantino didn’t usher in a new, violent generation, and films are becoming much more prosocial than one would have expected.
Cinemagoing will undoubtedly survive. The new multiplexes are a glorious experience, offering perfect Sound and picture and very comfortable seats, thins which had died out in the 1980s. I can’t believe we’ve achieved that only to throw it away in favor of huddling around a 14-inch computer monitor to watch digitally delivered movies at home.
It will become increasingly cheap to make films, with cameras becoming smaller and lighter but remaining very precise. That means greater chances for new talent to emerge, as it will be much easier for people to learn how to be better film-makers. People’s working lives will be shorter in the future, and once retired they will spend a lot of time learning to do things that amuse them—like making videos. Fifty years on we could well be media-saturated as producers as well as audience; instead of writing letters, one will send little home movies entitled My Week. =
Which of the following about Internet is true according to the passage？ ______
A．break downB．break offC．break throughD．break away
根据客观性原则，会计核算应当真实反映企业的财务状况、经营成果，保证会计信息的真实性。()
Fermi Problem
On a Monday morning in July, the world’s first atom bomb exploded in the New Mexico desert. Forty seconds later, the shock waves reached the base camp where the Italian-American physicist Enrico Fermi and his team stood. After a mental calculation, Fermi announced to his team that the bomb’s energy had equated 10,000 tons of TNT. The bomb team was impressed, but not surprised. Fermi’s genius was known throughout the scientific world. In 1938 he had won a Nobel Prize. Four years later he produced the first nuclear chain reaction, leading us into the nuclear age. Since Fermi’s death in 1954, no physicist has been at once a master experimentalist and a leading theoretician.
Like all virtuosos, Fermi had a distinctive style. He preferred the most direct route to an answer. He was very good at dividing difficult problems into small, manageable bits—talent we all can use in our daily lives.
To develop this talent in his students. Fermi would suggest a type of question now known as a Fermi problem. Upon first hearing one of these, you haven’t the remotest notion of the answer, and you feel certain that too little information had been given to solve it. Yet when the problem is broken into sub-problems, each answerable without the help of experts or books, you can come close to the exact solution.
Suppose you want to determine Earth’s circumference without looking it up. Everyone knows that New York and Los Angeles are about 3,000 miles apart and that the time difference between them is three hours. Three hours is one eighth of a day, and a day is the time it takes the planet to complete one rotation, so its circumference must be eight times 3,000 or 24,000 miles. This answer differs from the true value, 24,902.45 miles, by less than four percent.
Ultimately the value of dealing with everyday problems the way Fermi did lies in the rewards of making independent discoveries and inventions: It doesn’t matter whether the discovery is as important as determining the power of an atom or as small as measuring the distance between New York and Los Angeles. Looking up the answer, or letting someone else find it, deprives you of the pleasure and pride that accompany creativity, and deprives you of an experience that builds up self-confidence. Thus, approaching personal dilemmas as Fermi problems can become a habit that enriches your life.
Fermi’s team was impressed by Fermi’s announcement in the base camp because he could even work out the power of the atom bomb in his mind.
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