Ｃｅｌｌ　Ｐｈｏｎｅ　Ｔａｔｔｌｅｓ

2008-09-26

中学科技 2008年9期

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

DNA is genetic material that appears in every cell. Like your fingerprint, your DNA is unique to you unless you have an identical twin. Scientists today routinely analyze DNA in blood, saliva, or hair left behind at the scene of a crime. The results often help detectives identify criminals and their victims.

Scientists wonder whether traces of DNA might linger on cell phones. To find out, a group of researchers collected flip-style phones from 10 volunteers. They used swabs to collect invisible traces of the users from two parts of the phone: the outside, where the user holds it, andthe speaker, which is placed at the user's ear.

The researchers scrubbed the phones using a solution made mostlyofalcohol. Theaim ofwashingwastoremoveall detectable traces of DNA. The owners got their phones back for another week. Then the researchers collected the phones and repeated the swabbing of each phone once more.

The scientists discovered DNA that belonged to the phone's owner on each ofthe phones. Bettersamples 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.

Surprisingly, DNA showed up even in swabs that were taken immediately after the phones were scrubbed. 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 list of clues that can clinch a crime-scene investigation.

参考译文：手机泄密

你的手机里藏有许多有关你的秘密。根据一项新的研究，除了你自己输进去的人名和电话号码以外，你的微量DNA也会在手机上留下痕迹。

DNA是每一个细胞里都存在的一种遗传物质。与指纹一样，每个人的DNA都不一样（除非你有一个与你一模一样的双胞胎兄弟姐妹）。今天，科学家对遗留在犯罪现场的血液、唾液或是毛发进行分析已经是司空见惯了，分析结果常常能帮助侦查人员确定罪犯和受害人。

科学家们想知道，是否会有微量DNA在手机上留下痕迹。为寻求答案，有一组研究人员从10名志愿者那里收集了10部翻盖式手机。他们用药签从手机的两个部位收集手机使用者的肉眼看不见的痕迹：一个部位是在手机的外面，使用者手握手机的地方；另一个部位是在放在使用者耳朵边的话筒。

研究人员用一种以酒精为主的溶液擦洗这些手机。擦洗的目的

是去除一切有可能检测到的DNA痕迹。然后让手机的主人把手机拿回去一个星期。随后研究人员把手机收集起来，用药签再一次对每个手机重做一遍上述的试验。

科学家们发现，在每一台手机上都留下了属于手机主人的DNA。在每台手机外部收集到的样本最清楚，不过那些药签上也检测到了别的一些人的DNA，这些人显然也曾触摸过手机。

令人惊异的是，甚至用药签在刚刚擦洗过的手机上抹一下也能检测到DNA。这就说明洗涤不可能完全清除罪犯用过的手机上所有可作证据的痕迹。因此，手机现在可以添加到能够确定犯罪现场调查的线索清单里面去了。（注意斜体字的译法）

Mind - reading Machine

Winning at "I spy" would be a whole lot easier if there were just some ways to know what your opponent was looking at. It's not too far-fetched an idea. A team of researchers in California has developed a way to (A) p what kinds of objects people are looking at by scanning what's (B)h in their brains.

When you look at something, whether it's a tomato or your backpack or your best friend, your eyes send a (C) s about that object to your brain. Different (D) r of the brain process the information your eyes send. Cells in your brain called neurons are responsible for this processing.

Likecells anywhereelseinyourbody, activeneuronsuse (1) o. Blood brings oxygen to the neurons, and the more active a neuron is, the more oxygen it will (E) c. The more active a region of the brain, the more active its neurons, and in turn, the more blood will travel to that region. And by using a (F) t called functional magnetic resonance imaging, or fMRI, scientists can visualize which parts of the brain receive more oxygen-rich blood and therefore, which parts are working to process (2) i.

An fMRI machine is a device that scans the brain and measures changes in blood flow to the brain. The technology shows researchers how brain activity changes when a person thinks, looks at something, or carries out an (3) a like speaking orreading. By highlighting the areas ofthe brain at work when a personlooks at different images, fMRImay help scientists determine specific (4) p of brain activity associated with different kinds of images. This is the working principle of fMRI, on which it can read your mind.

(A, B, C, D, E, F FOR CROSS, 1, 2, 3，4 FOR DOWN. Thefirst lettersoftheabsents were given)

TurnTheFish

Arrange 8 matchsticks to form the fish swimming left as shown in the illustration. The object of the puzzle is to move 3 matchsticks to make the fish swimming in the opposite direction, i. e. to the right.