Can people change their skin color without suffering like pop king Michael Jackson? Perhaps yes. Scientists have found the gene that determines skin color.
The gene comes in two versions, one of which is found in 99 per cent of Europeans. The other is found in 93 to 100 per cent of Africans, researchers at Pennsylvania State University report in the latest issue of Science.
Scientists have changed the color of a dark-striped zebrafish（斑马鱼） to uniform gold by inserting a version of the pigment (色素) gene into a young fish. As with humans, zebrafish skin color is determined by pigment cells, which contain melanin (黑色素). The number, size and darkness of melanin per pigment cell determine skin color.
It appears that, like the golden zebrafish, light-skinned Europeans also have a mutation (变异) in the gene for melanin production. This results in less pigmented skin.
However, Keith Cheng, leader of the research team, points out that the mutation is different in human and zebrafish genes.
Humans acquired dark skin in Africa about 1.5 million years ago to protect bodies from ultra-violet rays of the sun (太阳光紫外线), which can cause skin cancer.
But when modern humans leave Africa to live in northern latitudes, they need more sunlight on their skin to produce vitamin D. So the related gene changes, according to Cheng.
Asians have the same version of the gene as Africans, so they probably acquired their light skin through the action of some other gene that affects skin color, said Cheng.
The new discovery could lead to medical treatments for skin cancer. It also could lead to research into ways to change skin color without damaging it like chemical treatment did on Michael Jackson. The passage mainly tells us that ________.
| A．people can not change their skin color without any pain |
| B．the new discovery could lead to research into ways to change skin color safely |
| C．pop king Michael Jackson often changed his skin color as he liked |
| D．scientists have found out that people’s skin color is determined by the gene |
It can be inferred from the passage that ________.
| A．nowadays people who want to change their skin color have to suffer a lot from the damage caused by the chemical treatment |
| B．Europeans and Africans have the same gene |
| C．the new discovery could help to find medical treatments for skin cancer |
| D．there are two kinds of genes |
Scientists have done an experiment on a dark-striped zebrafish in order to ________.
| A．find the different genes of humans’ |
| B．prove the humans’ skin color is determined by the pigment gene |
| C．find out the reason why the Africans’ skin color is dark |
| D．find out the ways of changing people’s skin color |
The reason why Europeans are light-skinned is probably that _____
| A．they are born light-skinned people |
| B．light-skinned Europeans have mutation in the gene for melanin production |
| C．they have fewer activities outside |
| D．they pay much attention to protecting their skin |
The writer’s attitude towards the discovery is ________.
| A．neutral（中立的） | B．negative | C．positive | D．indifferent（冷漠） |
Is there a nationwide shortage of nurses? It’s hard to say．However, some characteristic symptoms often indicate that there is indeed a shortage．
One symptom is the vacancy rate, or the percentage of budgeted positions that are unfilled．New England’s hospitals currently report that an average of 7 to 12 percent of their registered nurse positions are vacant, the highest level since the last shortage in the late 1980s．Vermont has a relatively low vacancy rate, at 7．8 percent．But its vacancies were at 1．2 percent just five years ago．
Another symptom is the increased use of stopgap measures to fill empty positions．For instance, many nurses report an upswing in how frequently they are asked to stay past their shifts．According to Murphy, working in the St．Elizabeth’s Hospital, “The shortage has definitely created a lot of opportunities of overtime for our nurses, whether they want them or not．” Similarly, a national survey of registered nurses shows that in an average week, nurses in the U．S．work 2．4 more hours than they are scheduled to．Much of this extra time is voluntary, as nurses earn overtime pay when they stay to fill in blanks in the schedule．
When they can’t fill open positions by more traditional means, health care providers hire temporary staff to tide them over．Travelling workers are the largest part of the temporary health care workforce, hired for thirteen-week reduction at health care facilities facing short-term lack of workers．Temporary workers, mainly nurses, cost hospitals $ 7．2 billion in 2000．
“Any successful solution to the shortage depends on convincing more people to become nurses, and that is not an easy goal to reach．To achieve it,” says Buerhaus, “society needs to place more value on nursing．Legislation （法规） can’t do that – it should come from people．” And if this continues, we might have to learn to care for ourse
lves in the hospital．The temporary staff hired by a hospital _______．
| A．cost a large part of the hospital’s budget |
| B．meet the need for nurses in the hospital for a short time |
| C．should work on a weekly basis and on a scheduled timetable |
| D．ought to work passively for thirty continuous weeks |
According to Buerhaus, what is a successful solution to the nurse shortage?
| A．To convince people of the benefits of being a nurse． |
| B．To ask the government for help to work out specific legislation． |
| C．To publicize the past achievements of nurses． |
| D．To make people aware of the importance of being a nurse． |
What’s the probable meaning of the underlined word “upswing” in Paragraph 3?
| A．Symptom | B．Decrease | C．Increase | D．Figure |
What’s the author’s attitude towards nurse shortage?
| A．Worried | B．Indifferent | C．Doubtful | D．Optimistic |
Speeding off in a stolen car, the thief thinks he has got a great catch．But he is in for an unwelcome surprise．The car is fitted with a remote immobilizer, and a radio signal from a control centre miles away will ensure that once the thief switches the engine off, he will not be able to start it again．
The idea goes like this．A control box fitted to the car contains a mini-cellphone, a micro-processor and memory, and a GPS （全球定位系统） satellite positioning receiver．If the car is stolen, a coded （编码的） cellphone signal will tell the control centre to block the vehicle’s engine management system and prevent the engine being restarted．
In the UK, a set of technical fixes is already making life harder for car thieves．“The_pattern_of_vehicle_crime_has_changed,” says Martyn Randall, a security expert．He says it would only take him a few minutes to teach a person how to steal a car, using a bare minimum of tools．But only if the car is more than 10 years old．
Modern cars are far tougher to steal, as their engine management computer won’t allow them to start unless they receive a unique ID code sent out by the ignition （点火） key．In the UK, technologies like this have helped achieve a 31% drop in vehicle-related crime since 1997．
But determined criminals are still managing to find other ways to steal cars, often by getting hold of the owner’s keys．And key theft is responsible for 40% of the thefts of vehicles fitted with a tracking system．
If the car travels 100 metres without the driver confirming their ID, the system will send a signal to an operations centre that it has been stolen．The hundred metres minimum avoids false alarms due to inaccuracies in the GPS signal．
Staff at the centre will then contact the owner to confirm that the car really is missing, and keep police informed of the vehicle’s movements via the car’s GPS unit．The remote immobilizer is fitted to a car to ________．
| A．prevent car theft by sending a radio signal to the car owner |
| B．help the police make a surprise attack on the car thief |
| C．prevent the car thief from restarting it once it stops |
| D．allow the car to lock automatically when stolen |
By saying “The pattern of vehicle crime has changed”, Martyn Randall suggests that ________．
| A．it takes a longer time for the car thief to do the stealing |
| B．self-prepared tools are no longer enough for car theft |
| C．the thief has to make use of computer technology |
| D．the thief has lost interest in stealing cars over 10 years old |
________ is necessary in making a modern car tougher to steal．
| A．A coded ignition key | B．A unique ID card |
| C．A special cellphone signal | D．A GPS satellite positioning receiver |
The operations centre will first ________ after receiving an alarm．
| A．start the tracking system | B．contact the car owner |
| C．block the car engine | D．locate the missing car |
D
A mysterious machine found in a 2,000-year-old Greek shipwreck may have been used to calculate the positions of planets, predict when eclipses (日、月蚀) were to occur, and study other parts of astronomy (天文学). When it was found underwater about 100 years ago, the machine was in poor shape. Its metal pieces had become one mass (堆), and then broke into pieces.
When the researchers began to study what was left of the machine, they thought it might have something to do with astronomy. To find out more, they recently used advanced imaging methods, including X-ray computer tomography (断层摄影术), to look inside the metal parts and to check for ancient writing on the machine.
According to their research, the researchers believed that this machine could have been used to compute eclipses of the sun and moon and was also able to show the movements of planets. A user could pick a day in the future and, work out a planet’s position on that date by moving some sort of crank (曲柄) on the machine.
Besides, the researchers discovered that the machine had at least 30 bronze gears (齿轮) with as many as 225 teeth, likely all cut by hand.
With all the collected information, the researchers came up with a new model for how the machine operated. The model has 29 of the 30 known gears and five more that were probably there but never found. Also，the new picture adds a previously undiscovered spiral dial (螺旋刻度盘) to the back of the machine near the bottom. A hand moving around the dial could have pointed to eclipses over a period of 18 years.
71. The passage is most probably taken from _____.
A. a short-story collection
B. a popular science magazine
C. a political report
D. an old personal diary
72. What is the passage mainly about?
A. New research on calculating the positions of planets.
B. A popular way of computing eclipses of the sun and moon.
C. Scientists’ interest in the secrets of a 2,000-year-old Greek shipwreck.
D. A mysterious machine which could be used for astronomical research.
73. What do we learn from the third paragraph of the passage?
A. The machine might have been used to calculate the positions of the planets.
B. Scientists made great progress in predicting eclipses of the sun and moon.
C. The researchers discovered some secrets in the Greek shipwreck.
D. The machine can be of great help for people working out the sizes of planets.
74. The researchers made a new model because they____.
A. wished to repair the broken machine
B. wanted to study the shipwreck more conveniently
C. hoped to know how the machine worked
D. expected it to be used in modern scientific research
75. Which of the following statements is TRUE about the old machine?
A. It has 35 gears on it.
B. It has a spiral dial.
C. It was invented about 100 years ago.
D. Its gears have many teeth.
C
Since we are social beings, the quality of our lives depends in large measure on our interpersonal relationships. One strength of the human condition is our possibility to give and receive support from one another under stressful (有压力的) conditions. Social support makes up of the exchange of resources among people based on their interpersonal ties. Those of us with strong support systems appear better able to deal with major life changes and daily problems. People with strong social ties live longer and have better health than those without such ties. Studies over types of illnesses, from depression to heart disease, show that the presence of social support helps people defend themselves against illness, and the absence of such support makes poor health more likely.
Social support cushions stress in a number of ways. First, friends, relatives and co-workers may let us know that they value us. Our self-respect is strengthened when we feel accepted by others in spite of our faults and difficulties. Second, other people often provide us with informational support. They help us to define and understand our problems and find solutions to them. Third, we typically find social companionship supportive. Taking part in free-time activities with others helps us to meet our social needs while at the same time distracting (转移注意力) us from our worries and troubles. Finally, other people may give us instrumental support money aid, material resources, and needed services - that reduces stress by helping us resolve and deal with our problems.
66. Interpersonal relationships are important because they can ________
A. make people live more easily B. smooth away daily problems
C. deal with life changes D. cure types of illnesses
67. The researches show that people's physical and mental health _______
A. lies in the social medical care systems which support them
B. has much to do with the amount of support they get from others
C. depends on their ability to deal with daily worries and troubles
D. is related to their courage for dealing with major life changes
68. Which of the following is closest in meaning to the underlined word "cushions"?
A. takes place of B. makes up of
C. lessens the effect of D. gets rid of
69. Helping a sick neighbor with some repair work in spare time is an example of ________
A. instrumental support B. informational support
C. social companionship D. the strengthening of self-respect
70. What is the subject discussed in the text?
A. Interpersonal relationships. B. Kinds of social support.
C. Ways to deal with stress. D. Effects of stressful condition.
B
Have you ever wondered why you sometimes take an almost immediate liking to a person you have just met? We often get the first impression of a people based on the color of a person’s skin or the manner in which he or she dressed. Meaning is conveyed not only by words or verbal languages but also by nonverbal communication systems, such as body behaviors.
Nonverbal communication is important because we use the actions of others to learn about their affective emotional states .Our emotions are reflected in our posture, face, and eyes—be it fear, joy, anger, or sadness—so we can express them without ever saying a word .For this reason, most of us rely heavily on what we learn through our eyes.
Nonverbal communication is significant in human interaction because it is usually responsible for the first impressions. More importantly, those first messages usually influence the perception(感知) of everything else that follows. Even how we select friends and sexual partners is grounded in first impressions with nonverbal communication.
Nonverbal communication is important because it is culture-related. It is based on different beliefs, religions, values and customs in different cultures. When, where, how, and to whom people display his or her specific nonverbal behaviors is greatly affected by culture and context. Culture determines what the appropriate nonverbal behavior is. For example, feelings of friendship exist everywhere but their expression varies. It may be appropriate in some countries for man to embrace each other and for women to hold hands; in other countries these displays of affection may be shocking. Each culture has its own specific interpretation on nonverbal communication. What is acceptable in one culture may be completely unacceptable in another. One culture may determine that snapping fingers to call a waiter is acceptable; another may consider this gesture rude.
61. What is the best title of the passage?
A. Nonverbal communication and first impression
B. Nonverbal communication is culture-related
C. Nonverbal and verbal communication
D. The importance of nonverbal communication
62. We can know a person’s feeling through our eyes because_________.
A. we can see a person’s feeling on his face.
B. a person’s emotions can be reflected through eyes.
C. a person’s feeling can be reflected through his body languages
D. we can see a person’s feeling through his posture
63. Which of the following statements is not True?
A. Meaning can be conveyed both by words and body language.
B. We can use nonverbal communication to learn about a person’s emotional states.
C. We often get the first impression by what a person says.
D. The first impression can affect what we will do in the following.
64. How many reasons are mentioned in the text to show nonverbal communication is important?
A. 2 B. 3 C. 4 D.5
65. What can we conclude from the last paragraph?
A. we can use different ways to express friendship
B. each culture has its own specific interpretation on nonverbal communication
C. snapping fingers to call a waiter is acceptable
D. learning a country’s culture is very important.
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