SCIENCE IN THE NEWS

SCIENCE IN THE NEWS - September 10, 2002: South Asia's Pollution / El Nino in the Pacific / Anthrax-
Eating Enzyme¹

VOICE ONE:

This is Sarah Long.

VOICE TWO:

And this is Bob Doughty² with Science in the News, a VOA Special English program about recent developments
in science. Today, we tell about an enzyme that can destroy the deadly anthrax bacterium³. We tell about the
effects of a weaker weather condition called El Nino. And we tell about a cloud of pollution covering much of
southern Asia.

((THEME))

VOICE ONE:

American scientists say they have developed an enzyme that can destroy the deadly anthrax bacterium. The
scientists say the enzyme could effectively treat people infected with the bacterium, including drug-resistant
forms of the disease. They say the enzyme also could be used to immediately identify areas thought to contain
anthrax particles.

Scientists with the Rockefeller University in New York Cuty developed the anthrax-
killing protein. They described their work in the British publication Nature.

VOICE TWO:

Anthrax is a severe infectious⁴ disease that mainly attacks animals. However, anthrax
also can infect humans. Usually, people get the disease by touching⁵ infected animals
or animal products.

Anthrax
However, anthrax particles were blamed for five deaths in the United States last
year after the September eleventh terrorist⁶ attacks. Many other people became sick. The particles were found on
letters sent to political leaders and members of the media. The discovery of the letters containing anthrax
temporarily slowed mail service in the United States. No suspects have yet been charged in the investigation⁷.

VOICE ONE:

The United States Defense⁸ Department provided money for the new research on anthrax. The Rockefeller
University scientists developed the anthrax-killing enzyme by using a virus that attacks bacteria. Viruses can
infect both humans and bacteria. Viruses that infect bacteria are called bacteriophages or “bacteria-eating
viruses.” They are also known as phage (fayj).

Phage are the most common life form on Earth. They can be found in soil, water or anywhere else that bacteria
live. Phage have been battling anthrax and other kinds of bacteria for millions of years. Like viruses that infect
humans, phage inject their genetic⁹ material into the bacterial¹⁰ cell. Then, the virus reproduces¹¹ and bursts out
before attacking the next cell.

VOICE TWO:

The Rockefeller University scientists worked with phage that infect the anthrax bacterium. They identified the
enzyme that allows the phage to burst out and escape from the anthrax bacterium. The scientists showed that just
a small amount of the enzyme can quickly destroy a laboratory container filled with anthrax.

The scientists say this enzyme will attack only anthrax because it was developed from a phage that only infects


the anthrax bacterium.

The scientists tested the enzyme on mice infected with a disease similar to anthrax. All of the mice usually die
within four hours of being infected with this disease. The scientists injected the new enzyme into the mice fifteen
minutes after they were infected with the disease. As many as eighty percent of the injected animals survived.

VOICE ONE:

Vincent Fischetti of the Rockefeller University helped organize the study. He believes that the anthrax-killing
enzyme would work as well in humans, with almost no bad effects. He also thinks the bacterium used in the
anthrax attacks last year will not develop a resistance to the new treatment. That is because the enzyme is its
natural enemy.

The scientists also described how the enzyme can be used to confirm the presence of anthrax particles in places
like buildings. They say the test for anthrax can be done in as few as ten or fifteen minutes. Some current tests
require several days to identify the presence of anthrax. The new tests are done with a hand-held light meter. The
device shows glowing particles if anthrax is present.

((MUSIC BRIDGE))

VOICE TWO:

The El Nino weather condition has returned. However, officials at the United States National Weather Service
say El Nino is weaker than usual this year. El Nino is a change in the atmosphere over the Pacific Ocean. It
happens every four to five years.

El Nino is Spanish for “the little one” or “the Christ child.” The weather
condition is called El Nino because its effects increase in December, at about
Christmas time.

Normally, water temperatures in the western Pacific Ocean increase near the end of
the year. This causes more rainfall in Indonesia, Australia and other nearby places.
At the same time, cold ocean water causes less rainfall in the eastern Pacific Ocean,
near South America. The opposite happens during El Nino. Pacific Ocean
temperatures increase near South America, causing unusually high amounts of
rainfall there. And, El Nino causes dry weather in Indonesia and Australia.

VOICE ONE:

A strong El Nino can severely¹² affect the weather all over the world. The last powerful El Nino was in nineteen-
ninety-seven and nineteen-ninety-eight. It caused major floods around the world. El Nino also led to extremely
dry weather in some areas. Reports say the weather condition caused the deaths of about twenty-four-thousand
people.

So experts say having a weaker El Nino this year is good news. Weather scientists say rainfall has been higher
than usual in South America. The experts say the effects of El Nino will begin in November in the United States.
Drier weather is expected in the northwestern states. The northern states may have a warmer winter. But,
scientists say El Nino will not be strong enough to prevent this year’s powerful storms in the Atlantic Ocean.

((MUSIC BRIDGE))

VOICE TWO:

A United Nations study says a thick cloud of pollution covering southern Asia threatens the lives of millions of
people. Scientists say the pollution could increase lung diseases and cause early deaths. The cloud is also
damaging agriculture and affecting rainfall levels. Scientists are calling it the Asian Brown Cloud. It has affected¹³
Afghanistan, Bangladesh, Bhutan, India, Maldives, Nepal, Pakistan and Sri Lanka. The pollution cloud is three
kilometers high. Scientists say it can move halfway¹⁴ around the world in a week.

VOICE ONE:

An earlier El Nino (white
area)
(Photo -NOAA)

The cloud is a mixture of ash, acids, aerosols¹⁵ and other particles. It is the result of forest fires, the burning of
agricultural waste, and huge increases in the burning of fuels by vehicles, industries and power stations.

Pollution from millions of bad cooking stoves has made the problem worse. Many poor people burn fuels like
wood and animal waste in such stoves.

Scientists say the cloud of pollution appears to cool the land and oceans by blocking sunlight. They say it reduces
the amount of sunlight reaching the Earth’s surface by as much as fifteen percent. At the same time, heat inside
the cloud warms the lower parts of the atmosphere.

VOICE TWO:

Scientists say this combination could be changing winter rainfall levels in Asia. They say rainfall has increased
over the eastern coast of Asia. But it has dropped sharply¹⁶ over parts of northwestern Asia. The report says the
cloud could reduce rainfall over northwestern Pakistan, Afghanistan and western China by up to forty percent.

Harmful chemicals from the cloud are mixing with rainfall. This acid rain damages crops and trees and threatens
public health. Scientists are concerned that the pollution will intensify¹⁷ during the next thirty years as the
population of Asia increases to an estimated five-thousand-million people.

Scientists say the Asian Brown Cloud could affect other parts of the world unless steps are taken to reduce
pollution. Environmental groups say action is needed to find clean, renewable energy sources.

More than two-hundred scientists took part in the U-N study. The U-N Environment Program prepared the study
for the World Summit¹⁸ on Sustainable Development. That meeting took place in Johannesburg, South Africa. It
ended last week.

((THEME))

VOICE ONE:

This SCIENCE IN THE NEWS program was written by George Grow, Doreen Baingana 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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1 enzyme   

n.酵素，酶

参考例句：

• Above a certain temperature,the enzyme molecule will become unfolded.超过一定温度，酶分子将会展开。
• An enzyme that dissolves the fibrin of blood clots.能溶解血凝块中的纤维的酶。

2 doughty   

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。

3 bacterium   

n.(pl.)bacteria 细菌

参考例句：

• The bacterium possibly goes in the human body by the mouth.细菌可能通过口进入人体。
• A bacterium is identified as the cause for his duodenal ulcer.一种细菌被断定为造成他十二指肠溃疡的根源。

4 infectious   

adj.传染的，有传染性的，有感染力的

参考例句：

• Influenza is an infectious disease.流感是一种传染病。
• What an infectious laugh she has!她的笑声多么具有感染力啊！

5 touching   

adj.动人的，使人感伤的

参考例句：

• It was a touching sight.这是一幅动人的景象。
• His letter was touching.他的信很感人。

6 terrorist   

n.恐怖主义者，恐怖分子

参考例句：

• Without the gun,I'm a sitting duck for any terrorist.没有这支枪，我就成了恐怖分子下手的目标了。
• The district was put on red alert during a terrorist's bomb scare.这个地区在得到恐怖分子炸弹恐吓后作了应急准备。

7 investigation   

n.调查，调查研究

参考例句：

• In an investigation,a new fact became known, which told against him.在调查中新发现了一件对他不利的事实。
• He drew the conclusion by building on his own investigation.他根据自己的调查研究作出结论。

8 defense   

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。

9 genetic   

adj.遗传的，遗传学的

参考例句：

• It's very difficult to treat genetic diseases.遗传性疾病治疗起来很困难。
• Each daughter cell can receive a full complement of the genetic information.每个子细胞可以收到遗传信息的一个完全补偿物。

10 bacterial   

a.细菌的

参考例句：

• Bacterial reproduction is accelerated in weightless space. 在失重的空间，细菌繁殖加快了。
• Brain lesions can be caused by bacterial infections. 大脑损伤可能由细菌感染引起。

11 reproduces   

复制( reproduce的第三人称单数 )； 重现； 再版； 生殖

参考例句：

• The computer reproduces the data as a set of diagrams. 电脑使这些数据再现为一系列图表。
• The original reproduces clearly in a photocopy. 原件复印得十分清晰。

12 severely   

adv.严格地；严厉地；非常恶劣地

参考例句：

• He was severely criticized and removed from his post.他受到了严厉的批评并且被撤了职。
• He is severely put down for his careless work.他因工作上的粗心大意而受到了严厉的批评。

13 affected   

adj.不自然的，假装的

参考例句：

• She showed an affected interest in our subject.她假装对我们的课题感到兴趣。
• His manners are affected.他的态度不自然。

14 halfway   

adj.中途的，不彻底的，部分的；adv.半路地，在中途，在半途

参考例句：

• We had got only halfway when it began to get dark.走到半路，天就黑了。
• In study the worst danger is give up halfway.在学习上，最忌讳的是有始无终。

15 aerosols   

n.气溶胶( aerosol的名词复数 )；喷雾剂；（气体中的）浮粒；喷雾器

参考例句：

• Aerosols are present throughout the atmosphere. 气溶胶存在于整个大气层。 来自辞典例句
• Deodorants are available as aerosols or roll-ons. 除臭剂有喷雾装或滚抹装。 来自辞典例句

16 sharply   

adj.锐利地，急速；adv.严厉地，鲜明地

参考例句：

• The plane dived sharply and rose again.飞机猛然俯冲而后又拉了起来。
• Demand for personal computers has risen sharply.对个人电脑的需求急剧增长。

17 intensify   

vt.加强；变强；加剧

参考例句：

• We must intensify our educational work among our own troops.我们必须加强自己部队的教育工作。
• They were ordered to intensify their patrols to protect our air space.他们奉命加强巡逻，保卫我国的领空。

18 summit   

n.最高点，峰顶；最高级会议；极点

参考例句：

• They climbed up the mountain and reached the summit.他们爬山，最终达到了山顶。
• The summit of the mountain is lost in the cloud and mist.山顶隐没在云雾之中。