Medical drugs sometimes cause more damage than they cure. One solution to this problem is to put the drugs inside a capsule, protecting them from the body-and the body from them-until they can be released at just the right spot. There are lots of ways to trigger (引发) this release, including changing temperature, acidity, and so on. But triggers can come with their own risks-burns, for example. Now, researchers in California have designed what could be a harmless trigger to date: shining near-infrared light (NIR, 近红外线) on the drug in the capsule.
The idea of using light to liberate the drug in the capsule isn't new. Researchers around the globe have developed polymers (聚合物) and other materials that begin to break down when they absorb either ultraviolet (UV, 紫外线) or visible light. But tissues also readily absorb UV and visible light, which means the drug release can be triggered only near the skin, where the light can reach the capsule. NIR light largely passes through tissues, so researchers have tried to use it as a trigger. But few compounds (化合物) absorb NIR well and go through chemical changes.
That changed last year when Adah Almutairi, a chemist at the University of California, San Diego, reported that she and her colleagues had designed a polymer that breaks down when it absorbs NIR light. Their polymer used a commercially available NIR-absorbing group called o-nitrobenzyl (ONB). When they catch the light, ONB groups fall off the polymer, leading to its breakdown. But ONB is only a so-so NIR absorber, and it could be poisonous to cells when it separates from the polymer.
So Almutairi and her colleagues reported creating a new material for capsules that's even better.This one consists of a long chain of compounds called cresol groups linked in a polymer. Cresol contains reactive(易反应的) components that make it highly unstable in its polymeric form, a feature Almutairi and her colleagues use to their advantage. After polymerizing the cresols, they cap each reactive component with a light-absorbing compound called Bhc. When the Bhcs absorb NIR light, the reactive groups are exposed and break the long polymer into two short chains. Shining additional light continues this breakdown, potentially releasing any drugs in the capsule. What's more, Almutairi says, Bhc is 10 times better at absorbing NIR than is ONB and is not poisonous to cells.
According to the passage, which of the following could be the best trigger?
Why is ONB unsatisfactory?
Which word can be used to complete the following process of changes?
第三部分：阅读理解（共20小题；每小题2分，满分40分）
阅读下列短文，从每题所给的四个选项（A、B、C和D）中，选出最佳选项。
In old times, there was a story about a young athletic boy hungry for success, for whom winning was everything.
One day, the boy was preparing himself for a running competition in his small native village. He and two other young boys were to compete. A large crowd had gathered to witness the competition and a wise old man, upon hearing of the little boy, had travelled far to bear witness also.
The race started. Sure enough, the boy dug deep and showed his determination, strength and power. He came first. The crowd cheered and waved at the boy. The wise man remained still and calm. The little boy, however, felt proud and important.
A second race was called, and two new young challengers came forward to run with the little boy. The little boy finished first once again. The crowd again cheered and waved at the boy. The wise man expressed no opinion.
“Another race, another race!” shouted the little boy. The wise old man stepped forward and presented the little boy with two new challengers, a frail (虚弱的) old lady and a blind man. “What is this?” asked the little boy. “Race!” said the wise man. The race was started and the boy was the only finisher. The little boy raised his arms in delight. The crowd, however, was silent showing no happiness. “Why don’t they join in my success?” he asked the wise old man. “Race again,” replied the wise man. “This time, all three of you, finish together,” continued the wise man. The little boy thought a little, stood in the middle of the blind man and the frail old lady, and then took the two challengers by the hand.
The race began and the little boy walked slowly, ever so slowly, to the finishing line and crossed it. The crowd cheered and waved at the boy. The wise man smiled.
56. According to the passage, the young athletic boy _____.
A. was crazy about winning competitions
B. considered the blind man foolish
C. was angry with the wise man
D. showed no respect to the young challengers
57. The wise man went to watch the competitions to _____.
A. teach the boy a lesson B. show the crowd his wisdom.
C. help the lady and the blind man D. see whether the boy was powerful
58. Why did the crowd remain silent when the boy beat the lady and the blind man?
A. The boy was proud. B. The boy was impolite.
C. The boy was not helpful. D. The boy was overconfident.
59. What is the message conveyed in the story?
A. Small talk is helpful.
B. Love and kindness are rewarding.
C. Wisdom is more important than strength.
D. Sympathy should be given to the weak.
The old man walked with a cane(拐杖) slowly into the restaurant. His poor jacket, patched (打补丁的) trousers, and worn-out shoes made him stand out from the usual Saturday morning breakfast crowd. Unforgettable were his pale blue eyes that were bright like diamonds, large rosy cheeks, and thin lips held in a smile.
He walked toward a table by the window. A young waitress watched him and ran over to him, saying, “Here, Sir. Let me give you a hand with that chair.”
Without a word, he smiled and nodded a thank you. She pulled the chair away from the table. Steadying(稳住) him with one arm, she helped him move in front of the chair, and get comfortably seated. Then she pushed the table up close to him, and leaned his cane against the table where he could reach it.
In a soft, clear voice he said, “Thank you, Miss.”
“You are welcome, Sir.” She replied. “My name is Mary. I’ll be back in a moment. If you need anything, just wave at me!”
After he had finished a hearty meal of pancakes, bacon, and hot lemon tea, Mary brought him the change, helping him up from his chair and out from behind the table. She handed him his cane, and walked with him to the front door. Holding the door open for him, she said, “Come back and see us, Sir!”
He nodded a thank you and said softly with a smile, “You are very kind!”
When Mary went to clean his table, she was surprised. Under his plate she found a business card and a note written on the napkin, under which was a $100 bill.
The note on the napkin read, “Dear Mary, I respect you very much, and you respect yourself, too. It shows by the way you treat others. You have found the secret of happiness. Your kind gestures will shine through those who meet you.”
The man she had served was the owner of the restaurant. This was the first time that she, or any of his employees, had seen him in person(亲自).
71. The relationship between the old man and Mary was ______.
A. father and daughter B. employer and employee
C. waiter and customer D. uncle and nephew
72. Based on the passage, all of the following words can be used to describe Mary except _____.
A. kind B. considerate C. helpful D. calm
73. Mary ran over to the old man because _______.
A. the old man was the boss of the restaurant
B. she saw the old man had some difficulty moving and taking a seat
C. she was worried that the old man might cause trouble to the restaurant
D. the old man had asked her to wait on him
74. The man came to the restaurant _______.
A. to have breakfast
B. to see his employees
C. to find out how his restaurant was working
D. to see how Mary served customers
75. The words the man left on the napkin indicated that _______.
A. respecting others means respecting oneself
B. serving others is a respectable job
C. Mary would get a rise as a result of her kindness
D. Mary’s kind service would bring in more money for her
WASHINGTON (AP) — A chemical has caused a global food safety scare. In the U.S., White Rabbit candies from China were recalled(召回) after melamine(三聚氰胺) was found in California and Connecticut. Melamine levels in imported Chinese candies recalled in California were as high as 520 parts per million, about 200 times greater than the level set on Friday by the FDA (The Food and Drug Administration) for "acceptable" risk.
And Friday, a New Jersey company announced it was recalling a yogurt-type drink from China, Blue Cat Flavor Drink, after FDA testing found melamine.
No illnesses have been reported in the U.S., but experts are checking for any increase in reports of heath problems.
The FDA says baby formula(配方) sold here is safe, because producers do not use any materials from China. But officials expect more melamine recalls as they continue to test products in ethnic(少数民族) markets.
“However, tiny amounts of melamine, are not harmful in most foods, except baby formula,” said U.S. government experts Friday.
The FDA said Friday its safety experts had concluded that eating a minuscule amount of melamine — 2.5 parts per million — would not raise health problems, even if a person ate food every day that was infected with the chemical.
“It would be like if you had a million grains of sand and they were all white, and you had two or three that were black, that's kind of the level,” said Stephen Sundlof, director of the FDA’s food safety program.
The FDA guideline is meant to help federal and state investigators(调查员) check for infected foods from China at ports(港口) of entry and in Asian community shops around the country. “We are trying to recognize products that have levels we are really concerned(worried) about, rather than trying to find the last molecule,” said Sundlof.
67. The underlined word “minuscule” in Paragraph 6 means __________.
A. very small B. acceptable C. worried D. large
68. According to FDA, people in America needn’t be worried if _________.
A. food is infected with melamine below a level of 2.5 parts per million
B. baby formula contains no melamine
C. they buy candies for babies produced locally
D. foods imported from China are recalled
69. It can be inferred from the passage that _________.
A. America won’t import foods from China any more
B. America is still importing foods from China
C. manufactures do not use any ingredients from China for baby formula
D. all foods imported from China contain melamine
70. The passage is probably found in _________ section on the Internet.
A. News Reports B. International Trade
C. Science and Life D. Food and Health
Welcome to Hannibal!
HANNIBAL CONVENTION & VISITORS BUREAU
505 N. Third, Hannibal, MO 63641
(573) 221-2477·Fax: (573) 221 -6999
www. VisitHannibal. com
Hannibal, Missouri, founded in 1819, is known worldwide as the boyhood home of Samuel Langhorne Clemens (Mark Twain), 1835-1910. The Clemens family moved to Hannibal in 1839 from nearby Florida, Missouri when Sam was four years old. He spent his formative years here, leaving such a lasting impression that his childhood memories provided the basis for much of his writing. In later life during an interview in India he said, “All that goes to make the me in me is a small Missouri village on the other side of the globe”.
Besides Mark Twain, famous Hannibal residents(居民) that may interest tourists include:
Margaret Tobin Brown, known as “Unsinkable Molly Brown” after he survived the sinking of
the Titanic in 1912, was born in Hannibal in 1867.
William P. Lear, inventor of the automobile radio, the automatic pilot for airplanes and the Lear
Jet, was born here in 1902.
Cliff Edwards, actor and musician, was born here. He was known in Hollywood as “Ukelele
Ike”, provided the voice for “Jiminy Cricket” in Pinocchio and appeared in many films.
Admiral Robert E. Coontz, a native of Hannibal, became Commander of the United States
Fleet(舰队) in 1923.
Jake Beckley, known as “Old Eagle Eye”, played baseball for three major league teams. He was
inducted into the National Baseball Hall of Fame in 1971.
Helen Cornelius, country and western singer, is a Hannibal native.
William Henry Hatch, Hannibal lawyer who, while as a congressman (议员), played an
important role in making sure of the passage of agricultural legislation that established the position of Secretary of Agriculture in the Cabinet(内阁) of the President of the United States.
64. Hannibal, Missouri is known worldwide ________.
A. because the Clemens family used to live there
B. as the birthplace of Mark Twain
C. because Mark Twain spent his boyhood years there
D. for a number of notable people who once lived there
65. What Mark Twain said during an interview in India implies that _______.
A. the life he lived in Hannibal had a decisive influence on his whole life
B. he spent all his life in a small Missouri village
C. the years he spent in Hannibal left the deepest impression on his memory
D. if he had not been a native of Hannibal, he couldn’t have become famous
66. Among the famous Hannibal residents, __________.
A. Helen Cornelius was a western singer singing in the country
B. Cliff Edwards acted in the film Pinocchio
C. Jake Beckley made contributions to the American navy
D. William Henry Hatch worked as a politician
In 1901, H. G. Wells, an English writer, wrote a book describing a trip to the moon. When the explorers landed on the moon, they discovered that the moon was full of underground cities. They expressed their surprise to the “moon people” they met. In turn, the “moon people” expressed their surprise. “Why,” they asked, “are you traveling to outer space when you even don’t use your own space?”
H. H. Wells could only imagine travel to the moon. In 1969, human beings really did land on the moon. People today know that there are no underground cities on the moon. However, the question that the “moon people” asked is still an interesting one. A growing number of scientists are seriously thinking about it.
Underground systems are already in place. Many cities have underground car parks. In some cities, such as Tokyo, Seoul and Montreal, there are large underground shopping areas. The “Chunnel”, a tunnel connecting England and France, is another representative project of underground systems.
But what about underground cities? Japan’s Taisei Corporation is designing a network of underground systems, called “Alice Cities”. The designers imagine using surface space for public parks and using underground space for flats, offices, shopping and so on. A solar dome would cover the whole city.
Supporters of underground development say that building down rather than building up is a good way to use the earth’s space. The surface, they say, can be used for farms, parks, gardens, and wilderness. H. G. Wells’ “moon people” would agree. Would you?
60. The explorers in H. G. Wells’ story were surprised to find that the “moon people” ________.
A. knew so much about the earth
B. understood their language
C. lived in so many underground cities
D. were ahead of them in space technology
61. What does the underlined word “it” in Paragraph 2 refer to?
A. Discovering the moon’s inner space.
B. Using the earth’s inner space.
C. Meeting the “moon people” again.
D. Traveling to outer space.
62. What sort of underground systems are already here with us?
A. Offices, shopping areas, power stations.
B. Tunnels, car parks, shopping areas.
C. Gardens, car parks, underground cities.
D. parks, shopping centres, tunnels.
63. What would be the best title for the passage?
A. Alice Cities cities of the future.
B. Space travel with H. G. Wells.
C. Enjoy living underground.
D. Building down, not up.