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A new high-performance contact lens under development at the department for applied physics at the University of Heidelberg will not only correct ordinary vision defects but will enhance normal night vision as much as five times, making people＇s vision sharper than that of cats.
Bille and his team work with an optical instrument called an active mirror－a device used in astronomical telescopes to spot newly emerging stars and far distant galaxies. Connected to a wave-front sensor that tracks and measures the course of a laser beam into the eye and back, the aluminum mirror detects the deficiencies of the cornea, the transparent protective layer covering the lens of the human eye. The highly precise data from the two instruments—which, Bille hopes, will one day be found at the opticians (眼镜商）all over the world—serve as a basis for the production of completely individualized contact lenses that correct and enhance the wearer’s vision.
By day, Bille’s contact lenses will focus rays of light so accurately on the retina (视网膜）that the image of a small leaf or the outline of a far distant tree will be formed with a sharpness that surpasses that of conventional vision aids by almost half a diopter (屈光度).At night, the lenses have an even greater potential. “Because the new lens—in contrast to the already existing ones—also works when it’s dark and the pupil is wide open,” says Bille, “lens wearers will be able to identify a face at a distance of 100 meters”－80 meters farther than they would normally be able to see. In his experiments night vision was enhanced by an even greater factor: in semi-darkness, test subjects could see up to 15 times better than without the lenses.
Bille’s lenses are expected to reach the market in the year 30, and one tentative plan is to use the Internet to transmit information on patients’ visual defects from the optician to the manufacturer, who will then produce and mail the contact lenses within a couple of days. The physicist expects the lenses to cost about a dollar a pair, about the same as conventional one-day disposable lenses.
1
The new contact lens is meant for_____.
A.
those with vision defects
B.
astronomical observations
C.
the night blind
D.
optical experiments
本题答案：
A
B
C
D
参考答案：
A
系统解析：
第1段提到“新的高性能隐形眼镜不仅可以纠正普通的视力缺陷，还可以把正常的夜间视力提高5倍”，可得知这种眼镜是为有视力缺陷的人设计的，因此选择A。
2
What do the two instruments mentioned in the second paragraph refer to?
A.
The astronomical telescope and the wave-front sensor.
B.
The aluminum mirror and the wave-front sensor.
C.
The aluminum mirror and the laser beam.
D.
The active mirror and the contact lens.
本题答案：
A
B
C
D
参考答案：
B
系统解析：
第2段第2句提到“铝镜和波前传感器连接在一起。前者用来测量角膜的缺陷，角膜是在人眼睛晶状体外的起保护作用的一层透明物体；后者是追踪测量激光束往返人眼的过程。由此可知，这两种仪器指的是铝镜和波前传感器，答案为B。
3
Individualized contact lenses are lenses designed _____.
A.
to work like an astronomical telescope
B.
to process extremely accurate data
C.
to suit the wearer’s specific needs
D.
to test the wearer’s eyesight
本题答案：
A
B
C
D
参考答案：
C
系统解析：
根据第2段最后一句“作为生产完全个性化的隐形眼镜的基础。这种眼镜矫正并提高佩戴者的视力”，可知不同的人有不同的具体需求，必须测量他们的精确数据来设计，答案是C。
4
According to Bille, with the new lenses the wearer's vision _____.
A.
will be sharper by a much greater degree at night than in the daytime
B.
can be better improved in the daytime than at night
C.
may be broadened about 15 times than without them
D.
will be far better at night than in the daytime
本题答案：
A
B
C
D
参考答案：
A
系统解析：
第3段最后一句提到“在他的实验中，夜间视力提髙的倍数更大”。A中的by a much greater degree是原文by an even greater factor的近义改写，故选A。
5
Which of the followingis trueabout Biile’s lenses?
A.
They will be sold at a very low price.
B.
Their production process is complicated.
C.
Purchase orders can be made through the Internet.
D.
They have to be replaced every day.
本题答案：
A
B
C
D
参考答案：
A
系统解析：
文章最后一句提到“预期这种眼镜售价为大约1美元一对，和传统日抛型价格一样”，可知这种眼镜价格很便宜，选A。
Imagine eating everything delicious you want—with none of the fat. That would be great, wouldn’t it?
New “fake fat" products appeared on store shelves in the United States recently, but not everyone is happy about it. Makers of the products, which contain a compound called olestra, say food manufacturers can now eliminate fat from certain foods. Critics, however, say the new compound can rob the body of essential vitamins and nutrients and can also cause unpleasant side effects in some people. So it’s up to consumers to decide whether the new fat-free products taste good enough to keep eating.
Chemists discovered olestra in the late 1960s, when they were searching for a fat that could be digested by infants more easily. Instead of finding the desired fat, the researchers created a fat that can’t be digested at all.
Normally, special chemicals in the intestines (肠)“grab” molecules of regular fat and break them down so they can be used by the body. A molecule of regular fat is made up of three molecules of substances called fatty acids.
The fatty acids are absorbed by the intestines and bring with them the essential vitamins A, D, E, and K. When fat molecules are present in the intestines with any of those vitamins, the vitamins attach to the molecules and are carried into the bloodstream.
Olestra, which is made from six to eight molecules of fatty acids, is too large for the intestines to absorb. It just slides through the intestines without being broken down. Manufacturers say it’s that ability to slide unchanged through the intestines that makes olestra so valuable as a fat substitute. It provides consumers with the taste of regular fat without any bad effects on the body. But critics say olestra can prevent vitamins A, D, E, and K from being absorbed. It can also prevent the absorption of carotenoids (类胡萝卜素)，compounds that may reduce the risk of cancer, heart disease, etc.
Manufacturers are adding vitamins A, D, E, and K as well as carotenoids to their products now. Even so, some nutritionists are still concerned that people might eat unlimited amounts of food made with the fat substitute without worrying about how many calories they are consuming.
6
We learn from the passage that olestra is a substance that ____.
A.
contains plenty of nutrients
B.
makes foods fat-free while keeping them delicious?
C.
renders foods calorie-free while retaining their vitamins
D.
makes foods easily digestible
本题答案：
A
B
C
D
参考答案：
B
系统解析：
第2段第2句提到“生产含有Olestra化合物的食品的厂商认为使用Olestra能除掉某些食品中的脂肪”，在第6段，作者又指出“Olestra不为肠胃吸收，并能保持脂肪的美味而不对身体产生有害的影响”，因此B与文中所阐述的观点一致；A与文中提到Olestra会阻止人体吸收某些维生素和类胡萝卜素相悖；C、D同 样与原文的意思相悖。
7
The result of the search for an easily digestible fat turned out to be _____.
A.
just as anticipated
B.
commercially useless
C.
D.quite unexpected D.somewhat controversial
本题答案：
A
B
参考答案：
C
系统解析：
第3段提到“20世纪60年代后期，化学家在寻找一种容易为婴儿吸收的脂肪时发现了 Olestra,但却发现它根本不能为人体吸收”，因此，此结果是出乎意料的，C与此观点一致。
8
Olestra is different from ordinary fats in that ______.
A.
it facilitates the absorption of vitamins by the body
B.
it passes through the intestines without being absorbed
C.
it helps reduce the incidence of heart disease
D.
it prevents excessive intake of vitamins
本题答案：
A
B
C
D
参考答案：
B
系统解析：
第6段首句提到“Olestra因体积太大，含有6-8个脂肪酸分子,而不能被肠胃分解吸收”，因此B正确。A、D与文中所表达的意思相悖；只有类胡萝卜素才有此功能，因此C不对。
9
What is a possible negative effect of olestra according to some critics?
A.
It may increase the risk of cancer.
B.
It may spoil the consumers’ appetite.
C.
It may impair the digestive system.
D.
It may affect the overall fat intake.
本题答案：
A
B
C
D
参考答案：
A
系统解析：
第6段第5句提到“一些批评家认为Olestra阻止人体吸收维生素A、D、E、K和类胡萝卜素，而类胡萝卜素却是一种能减少癌症及心脏病发病率的化合物”，因此，A正确;B与文章所陈述之意相悖;C和D文中没有提及。
10
Why are nutritionists concerned about adding vitamins to olestra?
A.
People may be induced to eat more than is necessary.
B.
It may trigger a new wave of fake food production.
C.
It may lead to the over-consumption of vitamins.
D.
The function of the intestines may be weakened.
本题答案：
A
B
C
D
参考答案：
A
系统解析：
文章最后一段第2句提到“一些营养学家担心这样一来，人们也许会不加限制地享用由代脂肪制成的食品，从而摄取更多的热量”，A与文中所陈述的观点一致；其他三项在文中均没有进行陈述。
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