Your cell phone holds secrets about you. Besides the names and numbers that you’ve programmed into it, traces of your DNA remain on it, 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 usually analyze DNA in blood, saliva(唾液), or hair left behind at the scene of a crime. The results often help detectives identify criminals and their victims.
Meghan J. McFadden, a biologist at McMaster University in Hamilton, Ontario, heard about a crime in which the suspect bled onto a cell phone and later dropped the device. This made her wonder whether traces of DNA remained on cell phones --- even when no blood was involved. To find out, she and a colleague collected flip-style(翻盖式) phones from 10 volunteers. They collected invisible traces of the users from two parts of the phone: the outside, where the user holds it, and the speaker, which is placed at the user’s ear.
The scientists scrubbed(meaning “cleaned”) the phones using a liquid mixture made mostly of alcohol. The aim of washing was to remove all detectable traces of DNA. The owners got their phones back for another week. Then the researchers collected the phones and repeated collecting traces on each phone once more. They discovered DNA that belonged to the phone’s owner on each of the phones.
Surprisingly, DNA showed up even in swabs that were taken immediately after the phones were cleaned. That suggests that washing won’t remove all traces of evidence from a criminal’s cell phone. So cell phones can now be added to the list of clues that can help a crime-scene investigation.
McFadden decided to find out whether people leave their DNA on their cell phones when she ____ .
A. got her cell phone lost by chance
B. found a cell phone with blood on it
C. heard about a crime involving a cell phone
D. did research on cell phones
The scientists allowed the volunteers to keep their cell phones for a week in order to____.
A. let them leave their traces on their phones
B. avoid keeping their cell phones too long
C. give them a chance to get rid of their secrets
D. find out who is responsible for the crime
The last paragraph mainly tells us that cell phones ____ .
A. do harm to people B. should be often cleaned
C. disclose people’s secrets D. help deal with crimes
Which of the following is NOT mentioned in the passage?
A. The reason for collecting the phones from volunteers.
B. The technique of collecting DNA on the phones.
C. The method of removing traces of DNA on the phones.
D. The purpose of washing the cell phones.
科目：高中英语 来源： 题型：单选题
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科目：高中英语 来源：2011年湖北普通高等学校招生统一考试英语试卷 题型：阅读理解
Which are you more likely to have wath you at sny given mement—your cell phone or your wallet? Soon you may be able to throw your wallet away and pay for things with a quick wave of your smart phone over an electroue scannet.
In January, Starbucks announced that customers could start using their phones to buy coffee in 6,800 of its states. This is the first pay-by-phone practice in the U.S., but we’re likely to see more witeless payment alternatives as something called ucar field communcation(NFC)GETS IN TO America’s consumet electanies. Last Deccmbet some new smart phanes which cantain an NFC chip were introduced to the public.
Already in use in part of Asia and Europe, NFC allows shoppers to wave theie phones a few inchs above a payment terminal-a contact-free system build for speed and convenienc
e. plan a few incees live a payment tetminal a one a few ptaht need to be worked out, like who will get to collect the profitable trunsacian(交易)fees. Although some credit card providers have been experimenting with wave and pay systems that use NFC enabled credit cards, cellphone service providers truay try to mused their way into the point of sale (POS)market. Three big cell phone service p
roviders have formed a joinf tenture(合资企业)that will go into opention over the next 15 months. Its goal is“to lead the U.S. payments industry from cards to mobile phone.”
The other big NFC sue, apart from how paymeats will be processed, is security, For instance, what’s to stop a thief from digitally pickpocketing you? “We’re still not at the point where an attacker can just brush against yee in a crowd and steal all the money out of your phone,”says Jimmy Shah. A mobile security rescarcher, “Usera may also be able to set transaction timeits,requiring a password to be enteced for larger putchases.
Bussiness? Keep in mund you lost your smart phone, it can be located on a located on a map and remotely disabled. Plus, your phone can be password protected, Your wallet isn’t.
【小题1】What is predicted to happen in the U.S.?
| A．The expansion of cellphone companices. |
| B．The boom of pay by phone business. |
| C．The dissppearanceof credit cards. |
| D．The increase of Starbucks sales.s |
| A．ensure the safety of shoppers |
| B．collect transaction fees easily |
| C．make purchase faster and smpler |
| D．improve the quality of cellphones |
| A．strengthen their relationship |
| B．get a share in the payments industry |
| C．sell more cellphones |
| D．test the NFC teehnoingy |
| A．Stop the luneting of niet phones. |
| B．Stop a passwant. |
| C．Cat all the money out of their phones. |
| D．Can large purchases. |
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科目：高中英语 来源：2012-2013学年山西省山大附中高一下学期期中考试英语试卷（带解析） 题型：阅读理解
根据短文内容，从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。（共5题，每小题2分，满分10分）
Active listening is an essential skill in learning. It is when you listen carefully to make sure you understand and learn the information that is being conveyed. 1 Here are some things which can help you to listen actively.
Listen for the main point and major subpoints(次要点). Don’t just write everything down. Listen carefully and make sure you understand what the purpose of this lecture is. As you take down notes, keep the main point in mind and make sure you understand how these notes are related.
Listen for an organizational structure. Listen carefully to figure out how the ideas are organized and they will make more sense.
Pay attention to organizational cues（暗示）. 2 Pay close attention to the introduction, as it will probably indicate how you should organize your notes. If the lecture begins with, “ Today, I’m going to talk about three conflicts in the Middle East,” then you have a good idea of what’ s going to follow. Listen for “signpost” words to indicate a transition for one point to the next, such as “next” and “finally” and numerical signposts like “first” or “third”.
Listen with your eyes. 3 Watch the teacher and be aware of how he or she uses hand gestures, eye contact and other body language to convey points.
___4____ Put away the campus newspaper, your cell phone and anything else that might be more interesting than the lecture. Learning to concentrate and listen actively is an endurance(持久) skill. 5
| A． Speakers communicate information through nonverbal(不使用语言的) communication. |
| B． Unfortunately, many students don’t know how to listen actively when they attend classes. |
| C． If your teacher indicates that something is important ,mark it. |
| D． Make yourself do it, and it will get easier over time. |
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科目：高中英语 来源：2015届吉林省高一上学期期末考试英语试卷（解析版） 题型：信息匹配
根据短文内容，从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。
Active listening is an essential skill in learning. It is when you listen carefully to make sure you understand and learn the information that is being conveyed. 1 Here are some things which can help you to listen actively.
◆ 2 . Don’t just write everything down. Listen carefully and make sure you understand what the purpose of this lecture is. As you take down notes, keep the main point in mind and make sure you understand how these notes are related.
◆Listen for an organizational structure. Listen carefully to figure out how the ideas are organized and they will make more sense.
◆Pay attention to organizational cues (暗示). 3 Pay close attention to the introduction, as it will probably show how you should organize your notes. If the lecture begins with, “Today I’m going to talk about three ethnic conflicts (种族冲突) in the Middle East,” then you have a good idea of what’s going to follow. Listen for “signpost” words to show a transition (过渡) from one point to the next, such as “next” and “finally” and numerical signposts like “first” or “third”.
◆Listen with your eyes. 4 Watch the teacher and be aware of how he or she uses hand gestures, eye contact and other body language to convey points.
◆Remove distractions. Put away the campus newspaper, your cell phone and anything else that might be more interesting than the lecturer.
Learning to concentrate and listen actively is an endurance（耐力） skill. 5
A．Speakers communicate information through nonverbal communication.
B．Unfortunately, many students don’t know how to listen actively when they attend classes.
C．If your teacher indicates that something is important, mark it.
D．Make yourself do it, and it will get easier over time.
E. Listen carefully for words and phrases that reflect the organizational structure of the lecture.
F. Your teachers’ notes are probably organized into some kind of outline.
G. Listen for the main point and major sub-points.
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科目：高中英语 来源：上海市2010届高三上学期摸底考试 题型：阅读理解
Part B: Reading Comprehension 20%
A
Backpacks are convenient. They can hold your books, your lunch, and a change of clothes, leaving your hands free to do other things. Someday, if you don’t mind carrying a heavy load, your backpack might also power your MP3 player, keep your cell phone running, and maybe even light your way home.
Scientists from the University of Pennsylvania in Philadelphia and the Marine Biological Laboratory in Woods Hole, Mass., have invented a backpack that makes electricity from energy produced while its wearer walks.
The backpack’s electricity-creating powers depend on springs used to hang a cloth pack from its metal frame. The frame sits against the wearer’s back, and the whole pack moves up and down as the person walks. A mechanism with gears(传动装置) collects energy from this motion and transfers it to an electrical generator.
Surprisingly, the researchers found, people walk differently when they wear the springy packs. As a result, wearers use less energy than when carrying regular backpacks. Also, the way the new packs ride on wearers’ backs makes them more comfortable than standard packs.
The backpack could be especially useful for soldiers, scientists, mountaineers, and emergency workers who typically carry heavy backpacks. These people often rely on global positioning system(GPS) receivers, night-vision goggles(夜视镜), and other battery-powered devices to get around and do their work. Because the pack can make its own electricity, users don’t need to give up space in their packs to lots of extra batteries.
For the rest of us, power-generating backpacks could make it possible to walk, play video games, watch TV, and listen to music, all at the same time. Electricity-generating packs aren’t on the market yet, but if you do get one eventually, just make sure to look both ways before crossing the street!
65. The passage introduces a new kind of ______ backpack.
|
A．electronic |
B．electricity-producing |
|
C．electron-generating |
D．electricity-controlling |
66. The new backpack makes use of ______ to produce power.
batteries placed at the bottom of the frame
the motion of the pack while the wearer walks
energy the wearer consumes for carrying the pack
the collective motion of a mechanism and some gears
67. From the passage, we can infer that ______.
the backpacks of mountaineers may become smaller in the future
the new backpack can hardly be produced due to its potential danger
the new backpack will someday replace MP3 players and cell phones
the backpack will also provide electricity for lighting our houses
68. An enormous disadvantage of power-generating backpacks might be that ______.
they may stop working at any time
it takes quite a while to have the energy transferred
they may distract the wearer’s attention from road safety
they will be extremely heavy with the mechanism
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