DNA Fingerprinting

    DNA is the genetic material found within the cell nuclei of all living things. In mammals the strands of DNA are grouped into structures called chromosomes.¹ With the exception of identical siblings (as in identical twins)²，the complete DNA of each individual is unique.

    DNA fingerprinting is sometimes called DNA typing.³ It is a method of identification that compares bits of DNA. A DNA fingerprint is constructed by first drawing out a DNA sample from body tissue or fluid such as hair, blood, or saliva. The sample is then segmented using enzymes, and the segments are arranged by size. The segments are marked with probes and exposed on X-ray film，where they form a pattern of black bars — the DNA fingerprint.⁴ If the DNA fingerprints produced from two different samples match，the two samples probably came from the same person.

    DNA fingerprinting was first developed as an identification technique in 1985. Originally used to detect the presence of genetic diseases⁵，it soon came to be used in criminal investigations and legal affairs. The first criminal conviction based on DNA evidence⁶ in the United Statesoccurred in 1988. In criminal investigations, DNA fingerprints derived from evidence collected at the crime scene are compared to the DNA fingerprints of suspects. Generally, courts have accepted the reliability of DNA testing and admitted DNA test results into evidence. However, DNA fingerprinting is controversial in a number of areas： the accuracy of the results, the cost of testing, and the possible misuse of the technique.   

    The accuracy of DNA fingerprinting has been challenged for several reasons. First, because DNA segments rather than complete DNA strands are "fingerprinted" ； a DNA fingerprint may not be unique ； large-scale research to confirm the uniqueness of DNA fingerprinting test results has not been conducted. In addition，DNA fingerprinting is often done in private laboratories that may not follow uniform testing standards and quality controls. Also, since human beings must interpret the test, human error could lead to false results.

    DNA fingerprinting is expensive. Suspects who are unable to provide their own DNA to experts may not be able to successfully defend themselves against charges based on DNA evidence.

    Widespread use of DNA testing for identification purposes may lead to the establishment of a DNA fingerprint database.

 

词汇：

figerprinting /ˈfɪŋgəprɪnt/ n. 指纹法，指纹术 

nucleus /"nju:klɪəs/ n. 核，中心
genetic / dʒəˈnetɪk / adj. 遗传的 

mammal /ˈmæml/ n. 哺乳动物
chromosome /ˈkrəʊməˌsəʊm/ n. 染色体 

identification /"aɪˌdentɪfɪˈkeɪʃn/ n. 识别，鉴定，证明
enzyme /"enzaɪm/ n. 酶 

suspect /səˈspekt/ n. 嫌疑犯
fingerprint / ˈfɪŋgəprɪnt / n. 指纹 

saliva /səˈlaɪvə/ n. 唾液
segment /ˈsegmənt/ vt.  分割，分裂；切片，不笨
controversial / ˌkɒntrəˈvɜ:ʃl / adj. 有争议的 

uniform /"ju:nɪfɔ:ml/ adj. 一致的，相同的

注释：

1.In mammals the strands of DNA are grouped into structures called chromosomes.哺乳L动物的 DNA线被组合为称作染色体的各种结构。
2.With the exception of identical siblings (as in identical twins)：生物姊妹体除外（如完全相同的双胞胎）
3.DNA fingerprinting is sometimes called DNA typing. DNA 指纹检查法有时也称 DNA 印记法。
4.The segments are marked with probes and exposed on X-ray film, where they form a pattern of black bars - the DNA fingerprint.切片先用探针做标记，然后在X光片上曝光。胶片上形成 由黑色条纹组成的图案，这就是DNA指纹。
5.Originally used to detect the presence of genetic diseases ： (DNA 指纹法）开始是用来探测遗传病的存在
6.The first criminal conviction based on DNA evidence：基于 DNA 提供证据的首例定罪

Some people believe that using a DNA fingerprint may not be so reliable because____

A:the accuracy of DNA fingerprinting has been challenged B:no private laboratory follows uniform testing standards or quality controls C:mistakes are possible when researchers explain the results of their tests D:suspects may not have enough money to provide their own DNA to law-courts

A Some people will do just about anything to save money. And I am one of them. Take my family’s last vacation. It was my six-year-old son’s winter break form school, and we were heading home from Fort Lauderdale after a weeklong trip. The flight was overbooked, and Delta, the airline, offered us $400 per person in credits to give up our seats and leave the next day. I had meetings in New York，So I had to get back. But that didn’t mean my husband and my son couldn’t stay. I took my nine-month-old and took off for home. The next day, my husband and son were offered more credits to take an even later flight. Yes, I encouraged—okay, ordered—them to wait it out at the airport, to "earn" more Delta Dollars. Our total take: $1,600. Not bad, huh Now some people may think I’m a bad mother and not such a great wife either. But as a big-time bargain hunter, I know the value of a dollar. And these days, a good deal is something few of us can afford to pass up. I’ve made living looking for the best deals and exposing （揭露） the worst tricks. I have been the consumer reporter of NBC’s Today show for over a decade. I have written a couple of books including one titled Tricks of the Trade: A Consumer Survival Guide. And I really do what I believe in. I tell you this because there is no shame in getting your money’s worth. I’m also tightfisted when it comes to shoes, clothes for my children, and expensive restaurants. But I wouldn’t hesitate to spend on a good haircut. It keeps its shape longer, and it’s the first thing people notice. And I will also spend on a classic piece of furniture. Quality lasts. What does the author want to tell us

A:How to expose bad tricks. B:How to reserve airline seats. C:How to spend money wisely. D:How to make a business deal.

Being smart is the most expensive thing we do. Not in terms of money, but in a currency that is vital to all living things: energy. One study found that newborn humans spend close to 90 percent of their calories on building and running their brains. (Even as adults, our brains consume as much as a quarter of our energy.) If, during childhood, when the brain is being built, some unexpected energy cost comes along, the brain will suffer. Infectious disease is a factor that may rob large amounts of energy away from a developing brain. A great deal of research has shown that average IQ varies around the world, both across nations and within them.
Higher IQ predicts a wide range of important factors, including better grades in school, a higher level of education, better health, better job performance, higher wages, and reduced risk of obesity. So having a better understanding of variations in intelligence might yield a greater understanding of these other issues as well.
In a study in 2010, it was found that, among all the factors that affect intelligence, infectious disease works as the best predictor of the bunch. A recent study by Christopher Hassall and Thomas Sherratt repeated the study using more sophisticated statistical methods, and concluded that infectious disease may be the only really important predictor of average national IQ.
Support for this hypothesis comes not only from cross-national studies, but from studies of individuals. There have been many studies, for example, showing that children infected with intestinal worms have lower IQ later in life. Another study by Atheendar Venkataramani found that regions in Mexico that were the target of malaria eradication programs had higher average IQ than those that were not. In practical terms, however, this means that human intelligence is mutable. If differences in IQ across the world are largely due to exposure to infectious disease during childhood, then reducing exposure to disease should increase IQ.
Despite the strength of the findings, the study was not without its limitations. The researchers did their best to control for the effects of education. But what they really needed was to repeat their analysis across regions within a single nation, preferably one with standardized, compulsory education. The nation they chose was the United States. Average IQ varies in the states. Again, infectious disease was an excellent predictor of average state IQ. The states with the five lowest average IQ all have higher levels of infectious disease than the states with the five highest average IQ, and the relationship was good across all of the states in between.
So far, the evidence suggests that infectious disease is a primary cause of the global variation in human intelligence. Since this is a developmental cause, rather than a genetic one, it’s good news for anyone who is interested in reducing global inequality associated with IQ. It will allow people interested in using this information to raise the IQ of people around the world to target their efforts most effectively and efficiently.
We can learn from the first paragraph that

A:energy is the most important factor that affects intelligence. B:newborn babies spend more calories than adults in running their brains. C:extra energy cost may cause intellectual damage to children. D:there are IQ variations among and within nations.

Text 1 　　What would you do with 590m This is now a question for Gloria Mackenzie, an 84-year-old widow who recently emerged from her small, tin-roofed house in Florida to collect the biggest undivided lottery jackpot in history. If she hopes her new-found for tune will yield lasting feelings of fulfillment, she could do worse than read Happy Money by Elizabeth Dumn and Michael Norton. 　　These two academics use an array of behavioral research to show that the most rewarding ways to spend money can be counterintuitive. Fantasies of great wealth often involve visions of fancy cars and extravagant homes. Yet satisfaction with these material purchases wears off fairly quickly what was once exciting and new becomes old-hat; regret creeps in. It is far better to spend money on experiences, say Ms Dumn and Mr Norton, like interesting trips, unique meals or even going to the cinema. These purchases often become more valuable with time-as stories or memories-particularly if they involve feeling more connected to others. 　　This slim volume is packed with tips to help wage slaves as well as lottery winners get the most "happiness bang for your buck." It seems most people would be better off if they could shorten their commutes to work, spend more time with friends and family and less of it watching television (something the average American spends a whopping two months a year doing, and is hardly jollier for it).Buying gifts or giving to charity is often more pleasurable than purchasing things for oneself, and luxuries are most enjoyable when they are consumed sparingly. This is apparently the reason MacDonald’s restricts the availability of its popular McRib - a marketing trick that has turned the pork sandwich into an object of obsession. 　　Readers of “HappyMoney” are clearly a privileged lot, anxious about fulfillment, not hunger.Money may not quite buy happiness, but people in wealthier countries are generally happier than those in poor ones. Yet the link between feeling good and spending money on others can be seen among rich and poor people around the world, and scarcity enhances the pleasure of most things for most people. Not everyone will agree with the authors’ policy ideas, which range from mandating more holiday time to reducing tax incentives for American homebuyers. But most people will come away from this book believing it was money well spent。According to the last paragraph,Happy Money

A:has left much room for readers’criticism B:may prove to be a worthwhile purchase C:has predicted a wider income gap in the us D:may give its readers a sense of achievement

Text 1 　　What would you do with 590m This is now a question for Gloria Mackenzie, an 84-year-old widow who recently emerged from her small, tin-roofed house in Florida to collect the biggest undivided lottery jackpot in history. If she hopes her new-found for tune will yield lasting feelings of fulfillment, she could do worse than read Happy Money by Elizabeth Dumn and Michael Norton. 　　These two academics use an array of behavioral research to show that the most rewarding ways to spend money can be counterintuitive. Fantasies of great wealth often involve visions of fancy cars and extravagant homes. Yet satisfaction with these material purchases wears off fairly quickly what was once exciting and new becomes old-hat; regret creeps in. It is far better to spend money on experiences, say Ms Dumn and Mr Norton, like interesting trips, unique meals or even going to the cinema. These purchases often become more valuable with time-as stories or memories-particularly if they involve feeling more connected to others. 　　This slim volume is packed with tips to help wage slaves as well as lottery winners get the most "happiness bang for your buck." It seems most people would be better off if they could shorten their commutes to work, spend more time with friends and family and less of it watching television (something the average American spends a whopping two months a year doing, and is hardly jollier for it).Buying gifts or giving to charity is often more pleasurable than purchasing things for oneself, and luxuries are most enjoyable when they are consumed sparingly. This is apparently the reason MacDonald’s restricts the availability of its popular McRib - a marketing trick that has turned the pork sandwich into an object of obsession. 　　Readers of “HappyMoney” are clearly a privileged lot, anxious about fulfillment, not hunger.Money may not quite buy happiness, but people in wealthier countries are generally happier than those in poor ones. Yet the link between feeling good and spending money on others can be seen among rich and poor people around the world, and scarcity enhances the pleasure of most things for most people. Not everyone will agree with the authors’ policy ideas, which range from mandating more holiday time to reducing tax incentives for American homebuyers. But most people will come away from this book believing it was money well spent。This text mainly discusses how to

A:balance feeling good and spending money B:spend large sums of money won in lotteries C:obtain lasting satisfaction from money spent D:become more reasonable in spending on luxuries

— Excuse me, may I ask you some questions
— Sorry, I’m too busy and haven’t even a minute to ______.

A:spend B:spare C:share D:stop

— Excuse me, may I ask you some questions
— Sorry, I'm too busy and haven't even a minute to ______.

A:spend B:spare C:share D:stop

? ?Internet use appears to cause a drop in psychological health, according to research at Carnegie Mellon University.
? ?Even people who spent just a few hours a week on the Internet experienced more bad feelings and loneliness than those who was online less frequently, the two-year study showed. Researchers are puzzling over the results, which were completely contrary to their expectations. They expected that the Net would prove socially healthier than television, since the Net allows users to choose their information and to commnunicate with others.
? ?The fact that Internet use reduces time available for family and friends may account for the drop in psychological health, researchers hypothesized (推测). Faceless, bodiless "virtual" communication may be less psychologically satisfying than actual conversation, and the relationships formed through it may be shallower. Another possibility is that exposure to the wider world through the Net makes users less satisfied with their lives.
? ?"But it’s important to remember this is not about the technology, it’s about how it is used," says psychologist Christine Riley of Intel, one of the study’s sponsors. "It really points to the need for considering social factors in terms of how you design applications and services for technology. /

What’s the finding of the research undertaken at Carnegie Mellon University?

A:People spend more time on the Internet now. B:People spend less time with their families and friends now. C:The Net proves socially healthier than television. D:Internet use may cause a drop in psychological healt