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SCIENCE IN THE NEWS - First electronically controlled animal

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SCIENCE IN THE NEWS -May 21, 2002: First electronically controlled animals / Study of mothers and their

sons / Effects of global warming
Broadcast:
VOICE ONE:
This is Sarah Long.
VOICE TWO:
And this is Bob Doughty1 with SCIENCE IN THE NEWS, a VOA Special English program about recent


developments in Science. Today, we tell about the first electronically controlled animals. We tell about a study of
mothers and their sons. And we tell about some effects of the warming of the Earth on plants and animals.
((THEME)
)
VOICE ONE:

 

Scientists have controlled the movements of rats by attaching electrical controls to
the animals

brains. The scientists work at the State University of New York’s
Downstate Medical Center in Brooklyn.

John Chaplin worked on the experiment. He said scientists have controlled the way
animals act using other methods in the past. However, this is the first time scientists
have been able to directly control another creature with electronic signals. The
experiments were reported in the publication Nature.

In the experiments, the team attached wires to areas in the brains of five rats. They
also attached very small cameras and communications equipment to the rats. The scientists then sent radio signals
to the rats’
brains through the communications equipment. The signals caused the rats to move in the direction

the researcher wanted to send them.

VOICE TWO:

The electronics2 were attached to the rats’
brains in a complex way. The scientists made two electronic
connections to the right and left side of the animals

brains. Those places in the rats’
brains control the sense
of touch on their whiskers, the long hairs on either side of a rat’s nose. The researchers could cause the rats to
feel as if their whiskers had been touched. The researchers trained the rats to turn left or right when they felt a
signal in their whiskers.

The scientists also made an electrical connection to a place in the rats’
brains believed to control enjoyment3.
The researchers rewarded the rats for going in the right direction by affecting that brain area and making the rats
feel good. This process is known as behavior conditioning. It is very similar to giving food to an animal as a
reward for doing a desired action. But, in the recent experiment, it was done electronically.

VOICE ONE:

The researchers electronically guided the rats to do several things. Some rats climbed trees even though the rats
had never seen a tree before or had ever been outside. Some rats walked through big, bright, open fields, although
they normally avoid such areas. Other rats climbed steps and crossed narrow paths in high places. The scientists
used computers up to five -hundred meters away to control the animals.

The researchers received support for their experiment from the Army’s Advanced Research Projects Agency.
Military officials hope that an electronically controlled rat could be used to spy or to find land mines.


VOICE TWO:

The researchers also say that a controlled rat could be used to save lives after events like earthquakes. Rats could
find people trapped under wreckage4. Rats can move through very small spaces and can carry very small cameras
permitting rescuers to look for survivors5 hidden under tons of material.

Some reports have called these electronically controlled rats living robots. However, the rats are not true robots.
That is because the rats were rewarded for doing what the researchers wanted them to do. A robot does not need a
reward to act. It simply follows electronic signals.

((MUSIC BRIDGE))

VOICE ONE:

Many mothers believe that sons are more difficult to care for than daughters. Some
mothers have said, “My son will be the death of me yet.


A new study says there may be some truth in what those mothers say. The study
examined mothers who lived more than one-hundred years ago. It showed that
women who had many sons did not live as long as women who had many daughters.
Science magazine published the findings.


Scientists from Finland and Britain examined family records for the Sami (SAH-me)
people who lived in northern Europe between the seventeenth and nineteenth centuries. The scientists studied
family records kept by church officials between sixteen-forty and eighteen-seventy. They studied three-hundred-
seventy-five women who lived to be older than fifty.


VOICE TWO:


One of the scientists was Virpi Lummaa (VEER-pee LOOM-mah) of Cambridge University in England. She says
the records contain detailed6 information on the life events of the Sami. The Sami were a people who traveled
from place to place to follow groups of reindeer7 because they depended on the animals for food. They did not
have modern medicine.


She said her team found that the length of a woman’s life was not connected to the number of children but to
the sex of the children. Women who raised many sons had the shortest lives. The study said that giving birth and
raising each son reduced a woman’s life by an average of thirty-four weeks.


The study also found that having a daughter increased a woman’s life by an average of twenty-three weeks.
Among the Sami, women with many adult daughters had the longest lives.


VOICE ONE:


Samuli Helle (SAH-moo-lee HEY-leh) of the University of Turku in Finland helped supervise8 the study. He says
the reason for this difference may be linked to fewer problems giving birth to and caring for a daughter. He noted9
that daughters often help their mothers with work in the home. He said this could make life easier for women
who had many children.


The scientists also noted that there could also be biological reasons for this. Male fetuses10 produce the hormone11


testosterone that might suppress12 the mother’s defense13 system against disease. The scientists also noted that baby
boys often weigh more than baby girls. This results in more problems for mothers when giving birth. Baby boys
also require more care after birth.


The scientists say the results of the study may not be the same for women in industrial countries today. These
women have fewer children, healthier lives and modern medical care. But they said these kinds of effects might
still be found among women in developing countries.


((MUSIC BRIDGE)
)


VOICE TWO:

 


Scientists say the warming of the Earth’s atmosphere has begun to affect plant and

animal life around the world. Scientists from the University of Hanover in Germany

say global warming is affecting endangered species14, sea life and the change in

seasonal15 activities of organisms. Carbon dioxide and other heat-trapping gases in the

atmosphere cause global warming.

Studies show that the Earth’s climate has warmed by about six-tenths of one

degree Celsius16 during the past one-hundred years. Most of the increase has taken
place in the last thirty years.

The German scientists studied different animal and plant populations around the world in the past thirty years.
They say some species will disappear because they can not move to new areas when their home climate gets too
warm.

VOICE ONE:

The scientists say one of the biggest signs of climate change has been the worldwide reduction in coral reefs17.
Rising temperatures in the world’s warm ocean waters have caused coral to lose color and die.

In the coldest areas of the world, winter freezing periods are now happening later and ending earlier. Researchers
say these changes are having severe effects on animals such as penguins18, seals and polar bears.

Changes in temperature in the air can also affect the reproduction of some reptiles19 and amphibians20. For example,
the sex of baby painted turtles is linked to the average temperature in July. Scientists say even small temperature
increases can threaten the production of male turtles.

VOICE TWO:

In Europe, scientists say warmer temperatures are affecting the spring and autumn seasons. This is affecting the
growth of plants and delaying the flight of birds from one place to another.

Scientists also are concerned about invasions of warm weather species into traditionally colder areas. Rising
temperatures have been linked with diseases spread by mosquito insects in areas of Asia, East Africa and Latin
America.

Britain’s Meteorological Office says worldwide temperatures will continue to rise during the next one-hundred
years. It says how much these temperatures increase will depend on the success of worldwide policies designed
to slow global warming.

VOICE ONE:

This SCIENCE IN THE NEWS program was written by Mario Ritter, George Grow and Cynthia Kirk. It was
produced by Cynthia Kirk. This is Sarah Long.

VOICE TWO:

And this is Bob Doughty. Join us again next week for more news about science in Special English on the Voice
of America.


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点击收听单词发音收听单词发音  

1 doughty Jk5zg     
adj.勇猛的,坚强的
参考例句:
  • Most of successful men have the characteristics of contumacy and doughty.绝大多数成功人士都有共同的特质:脾气倔强,性格刚强。
  • The doughty old man battled his illness with fierce determination.坚强的老人用巨大毅力与疾病作斗争。
2 electronics 5q0xB     
n.电子器件,电子学,电子技术
参考例句:
  • About 45000 people worked in electronics in Scotland.苏格兰约有4.5万人在电子行业工作。
  • He wants to brush up his knowledge of electronics.他想温习他的电子学知识。
3 enjoyment opaxV     
n.乐趣;享有;享用
参考例句:
  • Your company adds to the enjoyment of our visit. 有您的陪同,我们这次访问更加愉快了。
  • After each joke the old man cackled his enjoyment.每逢讲完一个笑话,这老人就呵呵笑着表示他的高兴。
4 wreckage nMhzF     
n.(失事飞机等的)残骸,破坏,毁坏
参考例句:
  • They hauled him clear of the wreckage.他们把他从形骸中拖出来。
  • New states were born out of the wreckage of old colonial empires.新生国家从老殖民帝国的废墟中诞生。
5 survivors 02ddbdca4c6dba0b46d9d823ed2b4b62     
幸存者,残存者,生还者( survivor的名词复数 )
参考例句:
  • The survivors were adrift in a lifeboat for six days. 幸存者在救生艇上漂流了六天。
  • survivors clinging to a raft 紧紧抓住救生筏的幸存者
6 detailed xuNzms     
adj.详细的,详尽的,极注意细节的,完全的
参考例句:
  • He had made a detailed study of the terrain.他对地形作了缜密的研究。
  • A detailed list of our publications is available on request.我们的出版物有一份详细的目录备索。
7 reindeer WBfzw     
n.驯鹿
参考例句:
  • The herd of reindeer was being trailed by a pack of wolves.那群驯鹿被一只狼群寻踪追赶上来。
  • The life of the Reindeer men was a frontier life.驯鹿时代人的生活是一种边区生活。
8 supervise FrAww     
v.监督,管理,指导
参考例句:
  • We must supervise and speed up the fulfilment of assigned tasks.已经布置了的工作,应当认真督促检查。
  • Tomorrow he will supervise all the pupils taking the English examination.明天全体学生考英语,他将担任监考。
9 noted 5n4zXc     
adj.著名的,知名的
参考例句:
  • The local hotel is noted for its good table.当地的那家酒店以餐食精美而著称。
  • Jim is noted for arriving late for work.吉姆上班迟到出了名。
10 fetuses eae25b106f4ed68558631a5bf44c9293     
n.胎,胎儿( fetus的名词复数 )
参考例句:
  • DNA was extracted from fetuses at mid-gestation, about 10 days past conception. DNA从受孕大约10天后的中期妊娠胚胎中提取。 来自互联网
  • Brucellosis is a disease that causes fetuses to abort in cattle. 普鲁士菌病是一种可以导致牲畜胎儿夭折的疾病。 来自互联网
11 hormone uyky3     
n.荷尔蒙,激素,内分泌
参考例句:
  • Hormone implants are used as growth boosters.激素植入物被用作生长辅助剂。
  • This hormone interacts closely with other hormones in the body.这种荷尔蒙与体內其他荷尔蒙紧密地相互作用。
12 suppress sFDyQ     
vt.压制,镇压,查禁,抑制,阻止
参考例句:
  • He continued to suppress the people and serve the imperialists.他继续镇压人民,为帝国主义效劳。
  • She was struggling to suppress her sobs.她拼命不让自己哭出来。
13 defense AxbxB     
n.防御,保卫;[pl.]防务工事;辩护,答辩
参考例句:
  • The accused has the right to defense.被告人有权获得辩护。
  • The war has impacted the area with military and defense workers.战争使那个地区挤满了军队和防御工程人员。
14 species FTizN     
n.物种,种群
参考例句:
  • Are we the only thinking species in the whole of creation?我们是万物中惟一有思想的物种吗?
  • This species of bird now exists only in Africa.这种鸟现在只存在于非洲。
15 seasonal LZ1xE     
adj.季节的,季节性的
参考例句:
  • The town relies on the seasonal tourist industry for jobs.这个城镇依靠季节性旅游业提供就业机会。
  • The hors d'oeuvre is seasonal vegetables.餐前小吃是应时蔬菜。
16 Celsius AXRzl     
adj.摄氏温度计的,摄氏的
参考例句:
  • The temperature tonight will fall to seven degrees Celsius.今晚气温将下降到七摄氏度。
  • The maximum temperature in July may be 36 degrees Celsius.七月份最高温度可能达到36摄氏度。
17 reefs 0b9ff9fe6897bd050ab9e7711960aeb0     
礁体
参考例句:
  • The motorboat cut across swift currents and skirted dangerous reefs. 汽艇穿过激流,绕过险滩。 来自《现代汉英综合大词典》
  • Fish are abundant about the reefs. 暗礁附近鱼很多。 来自《简明英汉词典》
18 penguins fc5bf5a50fd6b440a35d113f324c5e75     
n.企鹅( penguin的名词复数 )
参考例句:
  • Why can penguins live in cold environment? 为什么企鹅能生活在寒冷的环境中? 来自《简明英汉词典》
  • Whales, seals, penguins, and turtles have flippers. 鲸、海豹,企鹅和海龟均有鳍形肢。 来自《现代英汉综合大词典》
19 reptiles 45053265723f59bd84cf4af2b15def8e     
n.爬行动物,爬虫( reptile的名词复数 )
参考例句:
  • Snakes and crocodiles are both reptiles. 蛇和鳄鱼都是爬行动物。 来自《简明英汉词典》
  • Birds, reptiles and insects come from eggs. 鸟类、爬虫及昆虫是卵生的。 来自《现代汉英综合大词典》
20 amphibians c4a317a734a700eb6f767bdc511c1588     
两栖动物( amphibian的名词复数 ); 水陆两用车; 水旱两生植物; 水陆两用飞行器
参考例句:
  • The skin of amphibians is permeable to water. 两栖动物的皮肤是透水的。
  • Two amphibians ferry them out over the sands. 两辆水陆两用车把他们渡过沙滩。

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