题目内容
A blind baby is doubly handicapped. Not only is it unable to see, but because it cannot receive the visual stimulus from its environment that a sighted child does, it is likely to be slow in intellectual development. Now the ten-month old son of Dr. and Mrs Dennis Daughters is the subject of an unusual psychological experiment designed to prevent a lag in the learning process. With the aid of a sonar-type electronic that he wears on his head, infant Dennis is learning to identify the people and objects in the world around him by means of echoes.
Dennis and a twin brother, Daniel, were born last September almost three months too early. Daniel died after five days, and Dennis developed retrolental fibroplasias, an eye disorder usually caused by overexposure to oxygen in an incubator. He went blind, but through a paediatrician at the premature unit where he was treated, the Daughterses were contacted by Dr. Tom Bower, a psychologist from the University of Edinburgh then serving a fellowship at the Stanford University Centre for Advanced Study in the Behavioural Sciences. Bower wanted to see how a blind infant might respond if given an echo-sounding device to help him cope with his surroundings and the Daughterses agreed to help.
By the time the child was six weeks old, his parents noticed that he continuously uttered sharp clicking sounds with his tongue. Bower explained that blind people often use echoes to orient themselves, and that the clicking sounds were the boy's way of creating echoes. This, Bower believd, made the child an ideal subject for testing with an electronic echosounding device.
Signals: The device used in the study is a refinement of the "Sonicguide", an instrument produced by Telesensory Systems, Inc., of Palo Alto, Calif., and used by blind adults in addition to sane or guide dog. As adapted for Dennis, it consists of a battery-powered system about the size of a half dollar that is on a headgear. A transmitter emits an ultrasonic pulse that creates an 80degree cone of sound at 6 feet. Echoes from objects within the cone are perceived as sounds that vary in pitch and volume with the size and distance of the object.
The closer an object is, the lower the pitch, and the larger the object, the louder the signal. Hard surfaces produce a sharp ping, while soft ones send back signals with a slightly fuzzy quality. An object slightly to the right of Denny's sends back a louder sound to his right ear than to the left. Thus, by simply moving his head right and left and up and down, he can not only locate an object but also get some notion of its shape and size, thanks to the varying qualities of sounds reaching his ears as the cone of ultrasound passes its edges. Dennis likes to use the device to play a kind of peek-a-boo with his mother. Standing on her knee and facing her directly, he receives a strong signal in both ears. By turning his head away, he makes her seem to disappear. "From the first time he wore it," says Mrs. Daughters, "it was like a light going on in his head."
The boy also learned to identify many objects, including his favourite toy, a rubber caterpillar with six antenna-like projections coming out of its body. And at six-and-a-half months, when a teething biscuit was held in front of Dennis, the child immediately grabbed it with both hands and put it into his mouth.
So far, the study has shown that a normal blind baby can employ echoes as well as, or even better than, an unsighted adult can. What remains to be determined is how well the device will help Dennis cope with his surroundings as he begins to walk and venture further into his environment. Meanwhile, Telesensory, Inc., is working on the development of a sonar device with somewhat the same sensitivity as Dennis's for use by school-age children.
The writer says that a blind baby is doubtly handicapped in comparison to a sighted child because ______.
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听力原文： Despite two failed attempts, the White House on Wednesday said it wanted the Senate to vote again to try to win confirmation of John Bolton as U.S. ambassador to the United Nations.
But Republican and Democratic senators said the stalemate continued on Bolton's nomination over demands from Democrats that the White House provide information they said would shed more light on his suit ability for the job.
The nomination of the blunt-spoken conservative has been held up by accusations he tried to manipulate intelligence and intimidated intelligence analysts to support his hawkish views in his post as the top U.S. diplomat for arms control.
"We continue to believe that John Bolton should have an up or down vote on the floor of the Senate. That remains our position," White House spokesman Scott McClellan said.
If that fails, McClellan declined to say whether Bush would favor bypassing the Senate with a presidential appointment while Congress takes its August recess.
"Discussion is still going on about Bolton, but we have to make some progress before we take it back to vote on it. We talked about it again this morning," Senate Majority Leader Bill Frist, a Tennessee Re publican, told reporters after mceting with President Bush on Tuesday morning.
In procedural votes in May and June, Democrats denied Republicans the 60 votes needed from the 100-member chamber to bring debate on Bolton to a close and move to a confirmation vote which would require a simple majority.
A number of senators said they expected Bush to make the recess appointment which would allow Bolton to take up the U.N. post and serve until January 2007.
There also have been questions whether Bolton would accept a recess appointment, which lawmakers said would send him to the United Nations in a weakened political position.
Norm Kin2, spokesman for Joseph Biden of Delaware, top Senate Foreign Relations Committee Democrat, said the Senate could quickly move to an up or down vote on Bolton if the White House turned over the requested information.
The White House has refused to turn over the material which it said was highly classified and concerned internal deliberations not relevant to Bolton's nomination.
The nomination of John Bolton has been held up ______
The confirmation of John Bolton as U.S. ambassador to the United Nations requires ______ in the Senate.
听力原文： Jewish settler Avi Farhan, determined not to give up his home over looking the sea when Israel quits the occupied Gaza Strip, is looking into becoming a Palestinian.
"I have met with Palestinians. I am willing to be a test case for peace and take up Palestinian citizenship," Farhan told Reuters. "It will hurt me to give up my Israeli citizenship, but I want to remain here."
One Palestinian official suggested he might be allowed to stay in overcrowded Gaza—home to 1.4 million Palestinians—as long as he obeyed Palestinian laws. Actual citizenship could only be decided on an individual basis and any applicant would have to meet the same conditions as anyone else.
Ordinary Gazans have long viewed the 8,500 settlers in the territory as bitter enemies living on land they want for a state.
Israeli Prime Minister Ariel Sharon plans to give up all 21 Jewish settlements in the Gaza Strip as well as four of 120 in the West Balk in what he bills "disengagement" from conflict with the Palestinians. With drawals start next month.
Farhan, a Libyan-born Jew who left Tripoli for Israel at the age of three in the wake of the 1948 war at Israel's creation, said seven families were willing to stay in the mostly secular Gaza settlement of Elei Sinai after Israeli troops leave.
Farhan, 59, helped establish Elei Sinai after being forced to leave the Sinai settlement of Yamit in 1982. Like the West Bank and Gaza, Israel captured Sinai in the 1967 war, but returned it to Egypt under a peace deal.
Jewish settler Avi Farhan can continue to stay in the occupied Gaza Strip ______.
Since the late 1970s, in the face of a severe loss of market share in dozens of industries, manufacturers in the United States have been trying to improve productivity and therefore enhance their international competitiveness through costcuttig programs. (Cost-cutting here is defining the amount of labor constant.) However, from 1978 through 1982, productivity -- the value of goods manufactured divided by the amount of labor input -- did not improve; and while the results were better in the business upturn of the three years following, they ran 25 percent lower than productivity improvements during earlier, post-1945 upturns. At the sametime, it became clear the harder manufactures worked to implement cost-cutting, the more they lost their competitive edge.
With this paradox in mind, I recently visited 25 companies; it became clear to me that the cost-cutting approach to increasing productivity is fundamentally flawed. Manufacturing regularly observes a "40, 40, 20" rule. Roughly 40 percent of any manufacturing-based competitive advantage derives from long-term changes in manufacturing structure (decisions about the number, size, location, and capacity of facilities) and in approaches to materials. Another 40 percent comes from major changes in equipment and process technology. The final 20 percent rests on implementing conventional cost-cutting. This rule does not be tried. The well-known tools of this approach -- including simplifying jobs and retraining employees to work smarter, not harder -- do produce results. But the tools quickly reach the limits of what they can contribute.
Another problem is that the cost-cutting approach hinders innovation and discourages creative people. As Abernathy's study of automobile manufacturers has shown, an industry can easily be come prisoner of its own investment in cost-cutting techniques, reducing its ability to develop new products. And managers under pressure to maximize cost-cutting will resist innovation because they know that more fundamental changes in processes or systems will wreak havoc with the results on which they are measured. Production managers have always seen their job as one of minimizing costs and maximizing output. This dimension of performance has until recently sufficed as a basis of evaluation, but it has created a penny-pinching, mechanistic culture in most factories that has kept away creative managers.
Every company I know that has freed itself from the paradox has done so, in part, by developing and implementing a manufacturing strategy. Such a strategy facturing and implementing a manufacturing strategy. Such a strategy focuses on the manufacturing structure and on equipment and process technology. In one company a manufacturing strategy that allowed different areas of the factory to specialize in different markets replaced the conventional cost-cutting approach; within three years the company regained its competitive advantage. Together with such strategies, successful companies are also encouraging managers to focus on a wider set of objectives besides cutting costs. There is hope for manufacturing, but it clearly rests on a different way of managing.
The author of the passage is primarily concerned with ______.
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