Cell Phone Lets Your Secret Out

Cell Phone Lets Your Secret Out（）

A.Generally
B.Surprisingly
C.Disappointedly
D.Shortly

Your cell phone holds secrets about you. Besides the names and (51) that you’ve programmed into it, traces of your DNA linger (逗留) on the device, according to a new study.

DNA is genetic material that (52) in every cell. Like your fingerprint, your DNA is unique to you (53) you have an identical twin. Scientists today routinely analyze DNA in blood, saliva (唾液), or hair left (54) at the scene of a crime. The results often help detectives identify (55) and their victims. Your cell phone can reveal more about you (56) you might think.

Meghan J. McFadden, a scientist at McMaster University in Hamilton, Ontario, heard about a crime in which the suspect bled onto a cell phone and later dropped the (57) . This made her wonder whether traces of DNA lingered on cell phones even when no blood was involved. (58) , she and colleague Margaret Wallace of the City University of New York analyzed the flip-open phones of 10 volunteers. They used swabs (药签) to collect (59) traces of the users from two parts of the phone: the outside, where the user holds it, and the (60) , which is placed at the user’s ear.

The scientists scrubbed the phones using a solution made mostly (61) alcohol. The aim of washing was to remove all detectable traces of DNA. The owners got their phones (62) for another week. Then the researchers collected the phones and repeated the swabbing of each phone once more.

The scientists discovered DNA that (63) to the phone’s speaker on each of the phones. Better samples were collected from the outside of each phone, but those swabs also picked up DNA that belonged to other people who had apparently also handled the phone. (64) , DNA showed up even in swabs that were taken immediately after the phones were scrubbed (擦洗). That suggests that washing won’t remove all traces of evidence from a criminal’s device. So cell phones can now be added to the (65) of clues that can decide a crime-scene investigation.

destroyed

absurd

desperate

damaged

正确

错误

Although it is a common belief that sleeping for at least eight hours a night is vital for health and well—being. the six. year study involving more than 1. 1 million Americans older than 30 found that those who slept for less than eight hours were far from doing themselves any long—term harm。

"Individuals who now average 6. 5 hours of sleep a night Can be reassured that this is a safe amount of sleep. From a health standpoint。there is no reason to sleep longer," said Daniel Kripke , a professor of psychiatry(精神病学)at the University of California, San Diego.

Dr. Kripke said. "We don’t know if long sleep periods lead to death. Additional studies are needed to determine if setting your alarm clock earlier will actually improve your health. "

The scientists. who were funded by the American Cancer Society, found at the best survival rates were among the men and women who slept for seven hours a night. Those who

slept for eight hours were 12 per cent more likely to die during the six—year period of the study,

when other factors such as diet and smoking were taken into account.

Even those who spent a mere five hours a night in bed lived longer than those who slept eight or more hours. However, an increasing death rate was found among those who slept for less than five hours.

Dr. Kripke said. "Previous sleep studies have indicated that both short-and long-duration(持续时间)sleep had higher mortality rates. However, none of those studies were large enough to distinguish the difference between seven and eight hours a night, until flow. \

more family-oriented

more profound

relatively formal

unusually popular