题目内容
Rabies is an ordinarily infectious disease of the central nervous system, caused by a virus and, as a rule, spread chiefly by domestic dogs and wild flesh-eating animals. Man and all warm-blooded animals are susceptible to rabies. The people of ancient Egypt, Greece and Rome ascribed rabies to evil spirits because ordinarily gently and friendly animals suddenly became vicious and violent without evident cause and, after a period of maniacal behaviour, became paralysed and died.
Experiments carried out in Europe in the early nineteenth century of injecting saliva from a rabid dog into a normal dog proved that the disease was infectious. Preventive steps, such as the destruction of stray dogs, were taken and by 1826 the disease was permanently eliminated in Norway, Sweden and Denmark. Though urban centres on the continent of Europe were cleared several times during the nineteenth century, they soon became reinfected since rabies was uncontrolled among wild animals.
During the early stages of the disease, a rabid animal is most dangerous because it appears normal and friendly, but it will bite at the slightest provocation. The virus is present in the sailvary glands(腺) and passes into the saliva so that the bite of the infected animal introduces the virus into a fresh wound. If no action is taken, the virus may become established in the central nervous system and finally attack the brain. The incubation(潜伏期) period varies from ten days to eight months or more, and the disease develops more quickly the nearer to the brain the wound is. Most infected dogs become restless, nervous, and irritable and vicious, then depressed and paralysed. With this type of rabies, the dog's death is inevitable and usually occurs within three to five days after the onset of the symptoms.
Anti-rabies vaccine(疫苗) is widely used nowadays in two ways. Dogs may be given three-year protection against the disease by one powerful injection, while persons who have been bitten by rabid animals are given a course of daily injections over a week or ten days. The mortality rate from all types of bites from rabid animals has dropped from 9% to 0.5%. In rare cases, the vaccine will not prevent rabies in human beings because the virus produces the disease before the person's body has time to build up enough resistance. Because of this, immediate vaccination is essential for anyone bitten by an animal observed acting strangely and the animal should be captured circumspectly, and examined professionally or destroyed.
Rabies is______.
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The selection of workers for particular jobs is essentially a problem of discovering the special intelligence and personality characteristics needed for the job and of devising tests to determine whether candidates have such intelligence and characteristics. The development of tests of this kind has long been a field of psycho- logical research.
Once the worker is on the job and has been trained, the fundamental aim of the industrial psychologist is to find ways in which a particular job can best be accomplished with a minimum of effort and a maximum of individual satisfaction. The psychologist's function, therefore, differs from that of the so-called efficiency expert, who places primary emphasis on increased production. Psychological techniques used to lessen the effort involved in a given job include a detailed study of the motions required to do the job, the equipment used, and the conditions under which the job is performed. These conditions include ventilation, heating, lighting, noise, and anything else affecting the comfort or morale of the worker. After making such a study, the industrial psychologist often determines that the job in question may be accomplished with less effort by changing the routine motions of the work itself, changing or moving the tools, improving the working conditions, or a combination of several of these methods. Industrial psychologists have also studied the effects of fatigue on workers to determine the length of working time that yields the greatest productivity. In some cases such studies have proven that total production on particular jobs could be increased by reducing the number of working hours or by increasing the number of rest periods, or "breaks", during the day. Industrial psychologists may also suggest less direct requirements for general improvement of job performance, such as establishing a better line of communication between employees and management.
One aim of psychological research is to ______.
Google was vastly better than anything that had come before: so much better, in fact, that it changed the way many people use the web. Almost overnight, it made the web far more useful, particularly for non- specialist users, many of whom now regard Google as the internet' s front door. The recent fuss over Google's stock market flotation obscures its far wider social significance: few technologies, after all, are so influential that their names become used as verbs.
Google began in 1998 as an academic research project by Sergey Brin and Lawrence Page, who were then graduate students at Stanford University in Palo Alto, California. It was not the first search engine, of course. Existing search engines were able to scan or "crawl" a large portion of the web, build an index, and then find pages that matched particular words. But they were less good at presenting those pages, which might number in the hundreds of thousands, in a useful way.
Mr Brin's and Mr Page's accomplishment was to devise a way to sort the results by determining which pages were likely to be most relevant. They did so using a mathematical recipe, or algorithm, called PageRank. This algorithm is at the heart of Google's success, distinguishing it from all previous search engines and accounting for its apparently magical ability to find the most useful web pages.
Untangllng the web
PageRank works by analysing the structure of the web itself. Each of its billions of pages can link to other pages, and can also, in turn, be linked to. Mr Brin and Mr Page reasoned that if a page was linked to many other pages, it was likely to be important. Furthermore, if the pages that linked to a page were important, then that page was even more likely to be important. There is, of course, an inherent circularity to this formula--the importance of one page depends on the importance of pages that link to it, the importance of wb4ch depends in turn on the importance of pages that link to them. But using some mathematical tricks, this circularity can be resolved, and each page can be given a score that reflects its importance.
The simplest way to calculate the score for each page is to perform. a repeating or "iterative" calculation (see article). To start with, all pages are given the same score. Then each link from one page to another is counted as a "vote" for the destination page. Each page's score is recalculated by adding up the contribution from each incoming link, which is simply the score of the linking page divided by the number of outgoing links on that page. (Each page's score is thus shared out among the pages it links to.)
Once all the scores have been recalculated, the process is repeated using the new scores, until the scores settle down and stop changing (in mathematical jargon, the calculation "converges"). The final scores can then be used to rank search results: pages that match a particular set of search terms are displayed in order of descending score, so that the page deemed most important appears at the top of the list.
We can infer from the lst paragragh that by "hit-or-miss" it is meant______.
Who is Johnny Depp？
SECTION B INTERVIEW
Directions: In this section you will hear everything ONCE ONLY. Listen carefully and then answer the questions that follow. Questions 1 to 5 are based on an interview. At the end of the interview you will be given 10 seconds to answer each of the following five questions.
Now listen to the interview.
听力原文：Officer: Mrs. Harrison (I-I), thanks very much for coming down here to the station. I --I know you've been through a terrible situation here today. Urn...I'd just like to go over some of the things that you told Sergeant Clark at the bank.
H: All right.
O: Uh, would you like a cup of tea？
H: No. No, I' m fine.
O: All right.
H: Thanks.
O: Well, urn ...could you describe the two people who robbed the bank for this report we're filling out here？ Now, anything at all that you can remember would be extremely helpful to us.
H: Well, uh ... just... I can only remember basically what I said before.
O: That's all right.
H: The man was tall.., uh... about six feet, and he had dark hair
O: Dark hair.
H: And he had a moustache.
O: Very good. All right, did he have any other distinguishing marks, I mean scars, for example, anything like that？
H: Scars ... urn.., no. No, none that I can remember.
O: Do you remember how old he was, by any chance？
H: Uh ... well, I --I guess around thirty ....
O: Around thirty.
H: ... may be younger, plus or minus a few years.
O: Mm-hmm. All right, do you, uh, remember anything about what he might have been wearing？
H: Yes. Yes, he---he had on a dark sweater, a----a solid colour. You know, the kind of colour young people fancy nowadays.
O: Or. Urn ... anything else that strikes you at the moment？
H: I --I remember he was wearing a light shirt under the sweater. A cotton one with dark, I think, dark stripes. It looked like a good brand.
O: Ah, very good.
H: Yes, yes.
O: Mm --hmm. All right, now, can you tell us anything about the female robber, Mrs. Harrison？
H: Well, I remember that she did most of the talking. She had the gun pointed at us and she told us to lie down, and not to move if we knew what was good for us. I remember it just felt like she was pointing the gun fight at me, and my little daughter was fight next to me and she--she was just so frightened...
O: Uh, Mrs. Harrison, could you describe her for us？
H: Ugh. She was wearing a wool sweater...
O: Ah, very good.
H: I remember it was a dark color, navy blue or...or dark grey.
O: dark grey, mm--hmm.
H: ... and I guess she was in her late twenties. Uh, her hair was short, very short and a bit curly.
O: Do you remember how tall she was？
H: Uh ...about the same as myself, around five four.
O: Five four, mm --hmm. All fight, do you, uh .... remember anything else about this woman？
H: Yes. I remember that the woman was wearing a pendant around her neck.
O: Uh--hmm.
H: I remember specifically because I was then near the counter, next to the bank manager, and my little daughter started to cry...
O: Oh.
H: ...and this woman came up to me and was very rude to my daughter. So I had a good look at her and ...and she was sort of, uh, pulling on the chain, uh, playing with the pendant.
O: Oh？
H: It was gold, uh, well, anyway, it looked like gold, and it got a strange shape.
O: Mm—hmm. Did either of them have any other, uh, noticeable characteristics, Mrs. Harrison？ Now, just take a moment
H: No, I don't...
O: ...to think about this.
H: No. No, and this is really all I can remember.
O: Well, did either of them wear glasses？
H: No, no, I' m sure of that.
O: Mm --hmm. All fight, Mrs. Harrison, I really appreciate what you've been through today. I' m just going to ask you to look at some pohtographs before you leave, if you don't mind. It won't take very long. Can you do that for me？
H: Oh, all fight.
O: Would you like to step this way with me, please？
H: Ok. Sure.
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