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Batteries Built by Viruses
What do chicken pox,the common cold,the flu,and AIDS have in common?They're all diseases caused by viruses,tiny microorganisms that can pass from person to person. It's no wonder that when most people think about viruses,finding ways to steer clear of viruses is what's on people's minds.
Not everyone runs from the tiny disease carriers,though. In Cambridge,Massachu- setts,scientists have discovered that some viruses can be helpful in an unusual way. They are putting viruses to work,teaching them to build some of the world's smallest rechargeable batteries.
Viruses and batteries may seem like an unusual pair,but they're not so strange for engi-neer Angela Beicher,who first came up with the idea. At the Massachusetts Institute of
Technology(MIT)in Cambridge,she and her collaborators bring together different areas of science in new ways.In the case of the virus-built batteries,the scientists combine what they know about biology,technology and production techniques.
Beicher's team includes Paula Hammond,who helps put together the tiny batteries,and
Yet-Ming Chiang,an expert on how to store energy in the form of a battery.“We're working on things we traditionally don't associate with nature，”says Hammond.
Many batteries are already pretty small. You can hold A,C and D batteries in your hand. The coin-like batteries that power watches are often smaller than a penny. However, every year,new electronic devices like personal music players or cell phones get smaller than the year before. As these devices shrink,ordinary batteries won't be small enough to fit in-side.
The ideal battery will store a lot of energy in a small package. Right now,Belcher's model battery,a metallic disk completely built by viruses,looks like a regular watch battery. But inside,its components are very small一so tiny you can only see them with a powerful microscope.
How small are these battery parts?To get some idea of the size,pluck one hair from your head. Place your hair on a piece of white paper and try to see how wide your hair is一 pretty thin,right?Although the width of each person's hair is a bit different,you could probably fit about 10 of these virus-built battery parts,side to side,across one hair. These micro-batteries may change the way we look at viruses.
Which of the following is true of Belcher's battery mentioned in paragraph 6?
A: It is made of metal.
B: It is a kind of watch battery.
C: It can only be seen with a microscope.
D: It is a metallic disk with viruses inside it.
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第一篇
Almost Human?
Scientists are racing to build the world's first thinking robot.This is not science fiction:
some say they will have made it by the year 2020.Carol Packer reports.
Machines that walk,speak and feel are no longer science fiction.Kismet is the name
of an android（机器人）which scientists have built at the Massachusetts Institute of
Technology(MIT).Kismet is different from the traditional robot because it can show
human emotions.Its eyes,ears and lips move to show when it feels happy,sad or bored.
Kismet is one of the first of a new generation of androids一robots that look like human
beings一which can imitate human feelings.Cog,another android invented by the MIT,
imitates the action of a mother. However,scientists admit that so far Cog has the mental
ability of a two-year-old.
The optimists（乐观主义者）say that by the year 2020 we will have created humanoids
（机器人）with brains similar to those of an adult human being. These robots will be
designed to look like people to make them more attractive and easier to sell to the public.
What kind of jobs will they do?In the future,robots like Robonaut,a humanoid invented by
NASA,Will be doing dangerous jobs,like repairing space stations.They will also be doing
more and more of the household work for us.In Japan,scientists are designing androids
that will entertain us by dancing and playing the piano.
Some people worry about what the future holds:will robots become monsters（怪物）?
Will people themselves become increasingly like robots?Experts predict that more and more
people will be wearing micro-computers,connected to the Internet,in the future.People
will have micro-chips in various parts of their body,which will connect them to a wide variety
of gadgets（小装置）.Perhaps we should not exaggerate（夸大）the importance of
technology,but one wonders whether,in years to come,we will still be falling in love,
and whether we will still feel pain.Who knows?
In the future robots will also
A:explore space.
B:entertain people.
C:move much faster.
D:do all of the housework.
第一篇
Almost Human?
Scientists are racing to build the world's first thinking robot.This is not science fiction:
some say they will have made it by the year 2020.Carol Packer reports.
Machines that walk,speak and feel are no longer science fiction.Kismet is the name
of an android（机器人）which scientists have built at the Massachusetts Institute of
Technology(MIT).Kismet is different from the traditional robot because it can show
human emotions.Its eyes,ears and lips move to show when it feels happy,sad or bored.
Kismet is one of the first of a new generation of androids一robots that look like human
beings一which can imitate human feelings.Cog,another android invented by the MIT,
imitates the action of a mother. However,scientists admit that so far Cog has the mental
ability of a two-year-old.
The optimists（乐观主义者）say that by the year 2020 we will have created humanoids
（机器人）with brains similar to those of an adult human being. These robots will be
designed to look like people to make them more attractive and easier to sell to the public.
What kind of jobs will they do?In the future,robots like Robonaut,a humanoid invented by
NASA,Will be doing dangerous jobs,like repairing space stations.They will also be doing
more and more of the household work for us.In Japan,scientists are designing androids
that will entertain us by dancing and playing the piano.
Some people worry about what the future holds:will robots become monsters（怪物）?
Will people themselves become increasingly like robots?Experts predict that more and more
people will be wearing micro-computers,connected to the Internet,in the future.People
will have micro-chips in various parts of their body,which will connect them to a wide variety
of gadgets（小装置）.Perhaps we should not exaggerate（夸大）the importance of
technology,but one wonders whether,in years to come,we will still be falling in love,
and whether we will still feel pain.Who knows?
In the future robots will also
A:explore space.
B:entertain people.
C:move much faster.
D:do all of the housework.
共用题干
Water一the Issue of This Century
The world is running short of freshwater. Populations are growing bigger and thirstier （渴的）,with the result that freshwater is becoming increasingly scarce（缺乏）.Half the world's wetlands have disappeared during the last century,while estimates suggest that wa- ter use will rise by 50% in the next 30 years.
The World Bank report estimates that as much as half of the world's population,concentrated in Africa,the Middle East and south Asia,will face“severe water shortages”by 2025.Local water conflicts and the loss of freshwater ecosystems appear large in some re- gions.
A similar picture emerges from the globe's salt water regions. Three-quarters of the world's people may live within 100km of the sea in 2025,putting even more pressure on stretched coastal ecosystems. Two thirds of fisheries（渔业）are exploited at or beyond their sustainable limits, and half the world's coral reefs（珊瑚礁）may perish in 100 years. Almost 60% of coral reefs and 34% of fish species are at risk from human activities,the Bank says.
The report concludes that there is ample evidence to justify immediate and coordinated action to safeguard supplies and use water more efficiently.
Fresh water consumption is rising quickly,and the availability of water in some regions is likely to become one of the most pressing issues of the 21st century.
A third of the world's popu1ation一around two billion people一live in countries that are experiencing moderate to high water shortages.That proportion could rise to half or more in the next 30 years unless institutions（制度）change to ensure better conservation and alloca- tion of water.
China is one country where the portents（征兆）are gloomy. The most waterstressed country in East Asia,China is exploiting 44%of its usable water,a figure projected to rise to6O%by 2020.Primary withdrawal of water of more than 60%is widely considered by water experts to exceed the environmental carrying capacity of a river basin system. Although
China's total use appears still to be reasonable,it has several basins that are severely stressed environmentally.
Withdrawals exceed environmental limits in Afghanistan and Pakistan,and will exceed them in India by 2020.In the Middle East and North Africa,only Morocco has unexploited water resources.The rest have exceeded environmental limits and many are mining aquifers （蓄水层）一bodies of water-bearing rock一the report says.
It is estimated that water use will rise by 50% in the next 30 years.
A: Right
B: Wrong
C: Not mentioned
Water一the Issue of This Century
The world is running short of freshwater. Populations are growing bigger and thirstier （渴的）,with the result that freshwater is becoming increasingly scarce（缺乏）.Half the world's wetlands have disappeared during the last century,while estimates suggest that wa- ter use will rise by 50% in the next 30 years.
The World Bank report estimates that as much as half of the world's population,concentrated in Africa,the Middle East and south Asia,will face“severe water shortages”by 2025.Local water conflicts and the loss of freshwater ecosystems appear large in some re- gions.
A similar picture emerges from the globe's salt water regions. Three-quarters of the world's people may live within 100km of the sea in 2025,putting even more pressure on stretched coastal ecosystems. Two thirds of fisheries（渔业）are exploited at or beyond their sustainable limits, and half the world's coral reefs（珊瑚礁）may perish in 100 years. Almost 60% of coral reefs and 34% of fish species are at risk from human activities,the Bank says.
The report concludes that there is ample evidence to justify immediate and coordinated action to safeguard supplies and use water more efficiently.
Fresh water consumption is rising quickly,and the availability of water in some regions is likely to become one of the most pressing issues of the 21st century.
A third of the world's popu1ation一around two billion people一live in countries that are experiencing moderate to high water shortages.That proportion could rise to half or more in the next 30 years unless institutions（制度）change to ensure better conservation and alloca- tion of water.
China is one country where the portents（征兆）are gloomy. The most waterstressed country in East Asia,China is exploiting 44%of its usable water,a figure projected to rise to6O%by 2020.Primary withdrawal of water of more than 60%is widely considered by water experts to exceed the environmental carrying capacity of a river basin system. Although
China's total use appears still to be reasonable,it has several basins that are severely stressed environmentally.
Withdrawals exceed environmental limits in Afghanistan and Pakistan,and will exceed them in India by 2020.In the Middle East and North Africa,only Morocco has unexploited water resources.The rest have exceeded environmental limits and many are mining aquifers （蓄水层）一bodies of water-bearing rock一the report says.
It is estimated that water use will rise by 50% in the next 30 years.
A: Right
B: Wrong
C: Not mentioned
Five minutes left,the outcome of the match was still in doubt.
A:result
B:judgment
C:decision
D:event
A:result
B:judgment
C:decision
D:event
共用题干
The Robot Man
According to Hans Moravec,universal robots will take over all the physical activities that we engage in,leaving us with little to do.Moravec sees four generations on the road to true universal robots. The first generation will be here by 2010 and will consist of free-ranging robots that can navigate by building an internal mental map of their surroundings.In new situations they'll be able to adapt,unlike today's mobile industrial robots.These robots will have the computing power to cope with simple speech and text recognition,and will be used for tasks such as domestic clean-ing.
The second generation will arrive around 2020 and will be distinguished by the ability to learn .Second generation robots are programmed with sets of primitive tasks and with feedback that provide"pleasure"and"pain"stimuli .For example,a collision provokes a negative response,a completed task would be positive.
Move forward another ten years to 2030 and you get to generation three.This robot can build internal simulations of the world around it. Before beginning a task,it can imagine what will happen in order to predict problems.If it has a free moment,it can replay past experiences and try variations in order to find a better way of如ing things next time .It could even observe a person or another robot performing a task and learn by imitation.For the first time,we have here a robot that can think.
By the time we get to generation four in 2040,Moravec predicts that robots will be able to: match human reasoning and behaviour;generalise abstract ideas from specific experience;and, conversely,compile detailed plans of action from general commands such as"earn a living"or "make more robots".
The Moravec manifesto（宣告）runs something like this. As robots start to become useful in generation one,they'll begin to take on many tasks in industry.Driven by the availability of this cheap and tireless labour force,the economy will boom and the demand for robots will grow so rapidly that they will soon become lowcost commodity items.So much so that they'll move into the home,where the domestic robot will relieve us of many chores.
With increasing automation in generations two and three,the length of the average working day will plummet,eventually to near zero. Most people will be unemployed as robots take over not just primary industry,but the service economy too.Moravec sees the fourth generation as an opportunity to surpass our human limitations.
These future machines will be our"mind children".Like biological children of previous generations,they will embody humanity's best hope for a long-term future.
The author's main purpose is to______.
A: describe the life of Hans Moravec
B: support the view that robots will play a major role in our life
C: make fun of the views of Hans Moravec
D: get people prepared for the threat of future robots
The Robot Man
According to Hans Moravec,universal robots will take over all the physical activities that we engage in,leaving us with little to do.Moravec sees four generations on the road to true universal robots. The first generation will be here by 2010 and will consist of free-ranging robots that can navigate by building an internal mental map of their surroundings.In new situations they'll be able to adapt,unlike today's mobile industrial robots.These robots will have the computing power to cope with simple speech and text recognition,and will be used for tasks such as domestic clean-ing.
The second generation will arrive around 2020 and will be distinguished by the ability to learn .Second generation robots are programmed with sets of primitive tasks and with feedback that provide"pleasure"and"pain"stimuli .For example,a collision provokes a negative response,a completed task would be positive.
Move forward another ten years to 2030 and you get to generation three.This robot can build internal simulations of the world around it. Before beginning a task,it can imagine what will happen in order to predict problems.If it has a free moment,it can replay past experiences and try variations in order to find a better way of如ing things next time .It could even observe a person or another robot performing a task and learn by imitation.For the first time,we have here a robot that can think.
By the time we get to generation four in 2040,Moravec predicts that robots will be able to: match human reasoning and behaviour;generalise abstract ideas from specific experience;and, conversely,compile detailed plans of action from general commands such as"earn a living"or "make more robots".
The Moravec manifesto（宣告）runs something like this. As robots start to become useful in generation one,they'll begin to take on many tasks in industry.Driven by the availability of this cheap and tireless labour force,the economy will boom and the demand for robots will grow so rapidly that they will soon become lowcost commodity items.So much so that they'll move into the home,where the domestic robot will relieve us of many chores.
With increasing automation in generations two and three,the length of the average working day will plummet,eventually to near zero. Most people will be unemployed as robots take over not just primary industry,but the service economy too.Moravec sees the fourth generation as an opportunity to surpass our human limitations.
These future machines will be our"mind children".Like biological children of previous generations,they will embody humanity's best hope for a long-term future.
The author's main purpose is to______.
A: describe the life of Hans Moravec
B: support the view that robots will play a major role in our life
C: make fun of the views of Hans Moravec
D: get people prepared for the threat of future robots
共用题干
The Weight Experiment
Nicola Walters has been taking part in experiments in Scotland to discover why humans gain and lose weight. Being locked in a small room called a“ calorimeter”（热量测量室）is one way to find out.
1 .The signs above the two rooms read simply“Chamber One”and“Chamber Two”.These are the calorimeters:4m by 2m white-walled rooms where human volunteers are locked up in the name of science .Outside these rooms another sign reads“Please do not enter work in progress” and in front of the rooms advanced machinery registers every move the volunteers make.Each day,meals measured to the last gram are passed through a hole in the wall of the calorimeter to the resident volunteer.
2 .Nicola Walters is one of twenty volunteers who,over the past eight months,have spent varying periods inside the calorimeter. Tall and slim,Nicola does not have a weight problem,but thought the strict diet might help with her training and fitness programme.As a self-employed community dance rorker,she was able to fit the experiment in around her work.She saw an advert for volun- teers at her local gym and as she is interested in the whole area of diet and exercise,she thought she would help out.
3. The experiment on Nicola involved her spending one day on a fixed diet at home and the next in the room.This sequence was repeated four times over six weeks.She arrived at the calorimeter at8:30 am on each of the four mornings and from then on everything she ate or drank was carefull) measured .Her every move was noted too,her daily exercise routine,timed to the last second. At regular intervals,after eating,she filled in forms about how hungry she felt and samples were taken for analysis.
4 .The scientists help volunteers impose a kind of order on the long days they face in the room. “The first time,I only took one video and a book,but it was OK because I watched TV the rest of the time,”says Nicola. And twice a day she used the exercise bike. She pedaled（踩踏板） for half an hour,watched by researchers to make sure she didn't go too fast.
5 .It seems that some foods encourage you to eat more,while others satisfy you quickly.Volunteers are already showing that high-fat diets are less likely to make you feel full.Believing that they may now know what encourages people to overeat,the researchers are about to start testing a high-protein weight-loss diet. Volunteers are required and Nicola has signed up for further sessions.
Nicola Walters had time for the experiments________.
A: the volunteers do
B:.because she does not have a weight problem
C: because the life there can be very boring
D: make people overeat
E: because she was her own boss
F:after passing a high-protein test
The Weight Experiment
Nicola Walters has been taking part in experiments in Scotland to discover why humans gain and lose weight. Being locked in a small room called a“ calorimeter”（热量测量室）is one way to find out.
1 .The signs above the two rooms read simply“Chamber One”and“Chamber Two”.These are the calorimeters:4m by 2m white-walled rooms where human volunteers are locked up in the name of science .Outside these rooms another sign reads“Please do not enter work in progress” and in front of the rooms advanced machinery registers every move the volunteers make.Each day,meals measured to the last gram are passed through a hole in the wall of the calorimeter to the resident volunteer.
2 .Nicola Walters is one of twenty volunteers who,over the past eight months,have spent varying periods inside the calorimeter. Tall and slim,Nicola does not have a weight problem,but thought the strict diet might help with her training and fitness programme.As a self-employed community dance rorker,she was able to fit the experiment in around her work.She saw an advert for volun- teers at her local gym and as she is interested in the whole area of diet and exercise,she thought she would help out.
3. The experiment on Nicola involved her spending one day on a fixed diet at home and the next in the room.This sequence was repeated four times over six weeks.She arrived at the calorimeter at8:30 am on each of the four mornings and from then on everything she ate or drank was carefull) measured .Her every move was noted too,her daily exercise routine,timed to the last second. At regular intervals,after eating,she filled in forms about how hungry she felt and samples were taken for analysis.
4 .The scientists help volunteers impose a kind of order on the long days they face in the room. “The first time,I only took one video and a book,but it was OK because I watched TV the rest of the time,”says Nicola. And twice a day she used the exercise bike. She pedaled（踩踏板） for half an hour,watched by researchers to make sure she didn't go too fast.
5 .It seems that some foods encourage you to eat more,while others satisfy you quickly.Volunteers are already showing that high-fat diets are less likely to make you feel full.Believing that they may now know what encourages people to overeat,the researchers are about to start testing a high-protein weight-loss diet. Volunteers are required and Nicola has signed up for further sessions.
Nicola Walters had time for the experiments________.
A: the volunteers do
B:.because she does not have a weight problem
C: because the life there can be very boring
D: make people overeat
E: because she was her own boss
F:after passing a high-protein test