【每日阅读训练第二期——速度越障4系列】【4-12】

whitethelittle

马老师今天期末考试所以还是小白继续发一次，今天的速度是voa的几则新闻，越障短一点是天文类。


【速度】


A Soft Body, but the Mind of a Robot
【计时1】
SHIRLEY GRIFFITH: This is SCIENCE IN THE NEWS in VOA Special English. I'm Shirley Griffith.
STEVE EMBER: And I'm Steve Ember. Today, we tell about soft-bodied robots -- robots that can move more easily than those made of metal. We also tell about efforts to control the disease malaria. And we tell about how being president of the United States can be good for your health.
(MUSIC)
SHIRLEY GRIFFITH: When many of us think of robots, we picture large, metal objects in the shape of humans, having difficulty moving around. But robots have come a long way. A team at Harvard University in Massachusetts recently developed a soft-bodied robot. The team based the design of its robot on sea creatures without hard shells or skeletons.
STEVE EMBER: The robotic device was made with soft materials called elastomers. It is about thirteen centimeters long and has four legs that can move separately. The movements are controlled by compressed air and can be operated from a computer.
George Whitesides led the Harvard researchers. The United States Department of Defense paid for the project.
The robot itself took two months to develop. In tests, researchers have guided the robot under a plate of glass less than three centimeters high. The researchers say their invention can move at a speed of about thirteen meters an hour.
A report about the robot was published in November in the journal Proceedings of the National Academy of Sciences.
SHIRLEY GRIFFITH: Increasingly, soft robots are being developed for difficult jobs like moving through a battlefield or wreckage from a natural disaster. The robot can move across uneven surfaces including small rocks and wet dirt.
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【计时2】
Earlier this year, scientists from Tufts University in Massachusetts developed another kind of soft robot made of silicone rubber. This robot is about ten centimeters long and shaped like a caterpillar. It is able to roll up into a ball shape and move itself forward.
But researchers say there are difficulties in making these robots move. For one, they want to find a way for the robot to transport its own power source. They are also hoping to improve its speed.
(MUSIC)
STEVE EMBER: The World Health Organization says malaria was responsible for seven hundred eighty-one thousand deaths in two thousand nine. Most of those deaths were in children in Africa. Worldwide there were two hundred twenty-five million cases of the disease.
Both of these numbers represent improvements. In two thousand there were an estimated two hundred thirty-three million cases of malaria and almost a million deaths.
Malaria remains a major problem in Africa, but there have been some successes. Deaths in Rwanda, for example, have been reduced by sixty percent.
SHIRLEY GRIFFITH: The main way for communities to control malaria is by controlling mosquitoes. The disease comes from a parasite spread through the bite of infected mosquitoes.
In a recent study, researchers in West Africa showed that an insecticide spray can greatly reduce malaria transmission. Researchers at the Center de Recherche Entomologique de Cotonou tested a chemical called bendiocarb. They tested it with indoor spraying at sites throughout Benin.
The study found there were fewer mosquito bites in homes sprayed with bendiocarb. More importantly, none of the three hundred fifty-thousand people who lived there got malaria-infected mosquito bites during the test.
STEVE EMBER:Malaria control efforts currently depend on things like chemically treated bed nets and spraying against mosquitoes. But scientists keep trying to find other ways to prevent the disease.
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【计时3】
There are still no vaccines to prevent malaria. But a number of vaccines remain under development. Most contain genetically engineered versions of a few proteins from the Plasmodium parasite.
Plasmodium is the organism that causes malaria. Those modified proteins are designed to get the body's defenses to launch an immune response against the Plasmodium. But the parasite contains thousands of proteins.
SHIRLEY GRIFFITH: Another experimental vaccine includes a deactivated version of the entire parasite. Robert Seder works at the National Institute of Allergy and Infectious Diseases, near Washington.
ROBERT SEDER: "So instead of picking out one or two or three genes, you have the potential for what we call breadth -- generating an immune response that would be broad rather than narrower. And so that would be a good thing."
Radiation is used to weaken the parasite so it cannot make people sick or get spread by a mosquito. To make the vaccine, scientists use the parasite at a time in its growth when the organism is called a sporozoite.
This idea has been known since the nineteen sixties. But Mr. Seder says a discovery by a researcher at a vaccine company cleared the way for progress.
ROBERT SEDER: "The major breakthrough here was that my collaborator, Stephen Hoffman at Sanaria, developed a method where he could isolate the sporozoites and purify them so that they could administer it as a vaccine to humans. And no one thought that that was possible."
But no one knew either if the weakened sporozoites would activate the immune system to protect against malaria. So researchers tested it on volunteers and found that it was safe -- there were only minor side effects. But it was not very effective. Only two out of forty-four volunteers were protected when bitten by malaria-infected mosquitoes.
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【计时4】
STEVE EMBER: To find out why, the researchers tested the vaccine on laboratory animals. They decided that the problem was the way the vaccine had been given to the volunteers. It was injected into the skin, to simulate the bite of a mosquito. Mr. Seder says it would have been more effective if it had been given directly into the blood.
For now, more testing is needed. A report on the testing appeared in Science magazine.
(MUSIC)
SHIRLEY GRIFFITH: Finally, many Americans say the hardest job in the world is being president of the United States. The man, or woman, who lives and works in the White House must be able to deal with problems twenty-four hours a day, seven days a week. Even on holidays or in the middle of the night, the president may have to make decisions that affect both people in this country and the rest of the world.
That is why some news media tell about changes in a president's personal appearance during his time in office. Last August, President Obama celebrated his fiftieth birthday. Some pictures showed him as a man with grayer hair and more lines on his face than when he first took office. And that got researcher S. Jay Olshansky to thinking. He studies aging at the University of Illinois at Chicago.
STEVE EMBER: Doctors nearly always say that high levels of stress are bad for your health. So people would expect a president's life to be shorter than average. Some people even say that being president could cause a person to age two times as fast as normal. But Professor Olshansky was not persuaded. So he examined the lives of the thirty-four American presidents who died of natural causes. He found that twenty-three of them lived longer than most people born at the same time.
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The average age of those thirty-four presidents when they died was seventy-three. If they had aged two times as fast as normal, they should have lived to be only sixty-eight point one years old. The professor also found that the first eight presidents lived an average of seventy-nine point eight years. At that time, modern medicines had not been invented, and most men lived only about forty years.
Four American presidents lived past ninety. John Adams, Herbert Hoover, and Ronald Reagan each lived ninety or more years. But Gerald Ford lived longer than any other president. He was ninety-three and a half when he died in two thousand six.
SHIRLEY GRIFFITH: Professor Olshansky says gray hair, hair loss and other changes are part of aging and may result from something in our genes. So presidents are no different from the rest of us. But the researcher thinks there are three reasons they outlive other people. Most presidents are well-educated. Many are wealthy when compared to other Americans. And they have the best medical care possible. They know how to stay healthy, and have the best doctors. As a result, they can afford to live a healthy life long after they leave the White House.
Professor Olshansky says, "It is a classic illustration of the benefits of socioeconomic status." His study was published last month in the Journal of the American Medical Association.
(MUSIC)
STEVE EMBER: This SCIENCE IN THE NEWS was written by Brianna Blake, Christopher Cruise and Jim Tedder. I'm Steve Ember.
SHIRLEY GRIFFITH: And I'm Shirley Griffith. Join us again next week for more news about science in Special English on the Voice of America.
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【越障】
Twin Moon Probes Start New Year by Entering Lunar Orbit
A pair of NASA spacecraft are ringing in the new year in grand style, with both now successfully circling the moon after journeying through space for more than three months.
The Grail-B probe entered lunar orbit today (Jan. 1) after firing its main engine at 5:05 p.m. EST (2205 GMT) in a 40-minute-long orbital-insertion burn, NASA officials said. It joins its twin spacecraft, Grail-A, which arrived at the moon yesterday evening (Dec. 31) after completing a similar maneuver.
The two probes are on a mission to study Earth's nearest neighbor from crust to core. After gradually circling down to super-low orbits, the pair will zip around the moon in tandem, working together to map the lunar gravity field in unprecedented detail, researchers said.
Scientists expect the probes' measurements to help unlock some longstanding mysteries about the moon's composition and evolution— mysteries that have withstood more than 100 moon missions over the years.
"You might think that, given all of these observations, we would know what there is to know about the moon," Grail principal investigator Maria Zuber, of the Massachusetts Institute of Technology, told reporters Wednesday (Dec. 28). "Of course that's not the case."
The moon's many secrets
Scientists think the moon formed after a Mars-size body struck Earth about 4.5 billion years ago. This titanic impact blasted huge amounts of material into space, and they eventually coalesced.
While this basic outline of the moon's origin is pretty well established, many mysteries remain about how the rocky body has evolved since then.
Chief among these puzzles, perhaps, is why the near side of the moon — the face we always see from Earth — is so different from the far side. For example, plains of volcanic rock (called maria) are much more widespread on the near side, and the far side is higher and more mountainous, with the lunar surface 1.2 miles (1.9 kilometers) higher in elevation, on average, than the near side.
"We don't actually know why the near side and far side of the moon are different," Zuber said. "We think that the answer is locked in the interior."
One possible explanation, proposed by researchers this August, is that the gigantic collision 4.5 billion years ago actually created two moons. The second moon, which was much smaller, later slammed into our moon's far side, the idea goes, spreading itself over the surface rather than creating a crater.
The Grail probes' observations could help determine whether that scenario is accurate, researchers said.
"We believe that we can obtain the information that we need to test this hypothesis," Zuber said.
Formation flying
The $496 million Grail (short for "Gravity Recovery And Interior Laboratory") mission launched Sept. 10. The two washing-machine-size probes then spent more than three months making their slow, circuitous way to the moon.
By comparison, NASA's manned Apollo 11 mission in 1969 reached the moon in three days. But Apollo 11 prioritized speed, while Grail's path is energy-efficient and has given engineers ample time to assess the probes' health and charge up their scientific gear, researchers said.
Grail-A and Grail-B still have some work to do from their initial lunar orbits to get into position. They'll spend two months circling lower and lower, eventually settling into orbits just 34 miles (55 kilometers) above the lunar surface by March.
Only then will the twin spacecraft begin their science campaign. They'll chase each other around the moon for 82 days, staying 75 to 225 miles (121 to 362 km) apart. [Video: Grail's Mission to Map Moon Gravity]
Regional differences in the lunar gravity field will cause the two spacecraft to speed up or slow down slightly, changing the distance between them as they fly. Bouncing microwave signals back and forth off  each other, Grail-A and Grail-B will gauge these tiny distance variations constantly.
The Grail team will use the twin probes' measurements to construct highly detailed maps of the moon's gravitational field. These maps are expected to reveal a great deal about lunar composition, allowing scientists to draw insights about how the moon formed and how it has changed over time, researchers said.
Public outreach and education are a big part of the Grail mission. Each spacecraft is carrying four cameras and will snap photos of the lunar surface at the direction of middle-school students across the country. Students will get to pore over these pictures after they're beamed back down to Earth.
The photo project — which is called MoonKam and is run by former NASA astronaut Sally Ride — has already generated lots of enthusiasm. More than 2,100 schools have signed up to participate, according to Zuber.
"We've had a great response to the MoonKam project," Zuber said. "We're still accepting applications. We can accommodate another several hundred schools into the program if there's interest in doing that."
【796】

fox0923

吗啡不是在我后面吗？怎么今天小白替他发了，我可怜的文章啊~~

---------------------------------------------------------------
汇报：
1‘10"1'26"
2'02"
1'42"
1'31"


没想到当总统可以长寿的，还以为原因是因为压力大的可以促进什么肾上腺素之类的，看来猜错了~~

铁板神猴

吗啡不是在我后面吗？怎么今天小白替他发了，我可怜的文章啊~~

-- by 会员 fox0923 (2012/1/3 23:31:46)

fox…… 你好像应该是昨天发的周一晚上发周二的帖

fox0923

吗啡不是在我后面吗？怎么今天小白替他发了，我可怜的文章啊~~

-- by 会员 fox0923 (2012/1/3 23:31:46)

fox…… 你好像应该是昨天发的周一晚上发周二的帖

-- by 会员 铁板神猴 (2012/1/3 23:43:50)

我囧~~我还以为昨天是小白，看错了，小白前天发的，对不起啦，脑袋糊涂了~~我跟lei说一下看看给补上。谢谢神猴了！

铁板神猴

TO FOX
您有时差，是容易搞混~

此楼顺便占给明天做速度

计时：
1’42’’
2’04’’
2’00’’
1’52’’
1’36’’

shaoling

还好昨天没新帖，刚好可以赶上进度~哈哈~
占楼明天做咯~

1'14
1'21
1'13
1'28
1'10

越障：5‘10
NASA又发射了一枚探测月球的卫星，G-B，跟之前发射的另一枚G-A一起探测月球
月球的起源：认为多少年前某个星体爆炸，炸出了很多物体，形成了月球
月球的两面为什么有这么大的区别，传统的观点什么什么，有可能是月球内部造成的，然后有一个新的观点是认为原来形成的时候有两个月球，然后slam什么，大概就是那另一个影响了这个吧
那两枚卫星共同探测月球，每个上面装了4台照相机，给月球拍照，他们要运行多少个月，行驶多少距离
最后说这些照片可以公开给中学生，而且学校可以参与项目之类的

myancamel

前五篇1分钟内
170
180
210
230
180

5‘48
发射了两个飞船探测器，主要目的是研究月球

为什么要研究月球？
主要解决月球从地球分离出去的问题
其中核心是靠近地球的部分和远离地球的部分为什么那么不一样

两个飞行器飞行，着陆，调整介绍

安装摄像机

照片对中学公开

fkc8568

速度：2‘28  1’55  2’05  2‘15  1’57
越障：7‘08
      讲G-A和G-B两个飞船在新年进入了月球轨道，他们被用来研究月球从外壳到核心的种种问题，包括月球引力，成分，和演变。最主要的研究是为什么月球对着地球那一面和背对地球那一面的地貌有如此的不同，有一种猜测说曾经有一个小月球和现在的月球相撞，balabala。。。
   这两个飞船还需要时间进入正式轨道并在三月开始运作，届时将会展示月球的引力分布图以供将来的研究，同时飞船所拍摄的照片可以提供给有兴趣的学生学习

hexiaomu77

1  01:40
2  01:39
3  01:36
4  01:29
5  01:35
05:35
越障：1、讲一前一后GB和GA两个发射的卫星到月球之上来探测月球，尤其是它的evolution（通过探测月球外部到core）
2、意义：（最大）puzzle月球表面有difference between near side and far side，举例：volcanic rock 和很高的moutain的差别，原因也许是两个月球先后形成的原因。
3、How：；两个卫星保持一定举例逐渐向月球靠近，跟阿波罗11不同，它们并非有speed取胜，而是时间足够久（energy多），但是这个距离会随着regional difference 的影响而产生差异，但是这个距离可以gauge出来
3、最后：有2000多所大学加入了photo project中来，可以绘制出一幅月球的map

whitethelittle

吗啡晚上急吼吼的让我带他发，我看没有4-12我估计就是4-12了没想到原来狐狐也忘了