VOA慢速英语2010年-SCIENCE IN THE NEWS - Using Lasers to

FAITH LAPIDUS: This is SCIENCE IN THE NEWS in VOA Special English. I’m Faith Lapidus.
BOB DOUGHTY¹: And I’m Bob Doughty. Today, we will tell about a new cancer treatment and a study of the disease malaria². We will tell about the possibility of drier conditions in many populated areas. And we explain how cutting down on wasted food could lead to energy savings³.
(MUSIC)FAITH LAPIDUS: Doctors at the Mayo Clinic are using a process known as MRI-guided laser ablation to fight kidney and liver tumors. They are said to be among the first American doctors to use the process against the cancers.
Until now, doctors in the United States have used laser ablation mainly to treat tumors of the brain, spine⁵ and prostate.
Liver cancer is one of the most common cancers in the world. It is also the third leading cause of cancer death worldwide. Many liver cancer patients are too sick to survive traditional treatments, like chemotherapy and radiation. Even if they could, medical experts say these treatments only provide a small increase in life expectancy⁶.
BOB DOUGHTY: Eric Walser is an interventional⁷ radiologist with the Mayo Clinic in Florida. He was one of the first radiologists to use the MRI-guided laser ablation procedure to treat kidney and liver tumors. He says the process makes it possible for doctors to target and destroy tumors without damaging the rest of the organ.
Chemotherapy medicine is prepared for a liver cancer patient at the National Institutes of Health in Bethesda, Maryland Patients are placed inside an MRI machine. They are given a drug to keep them from moving during the procedure. A special needle is inserted directly into the tumor⁴ and light energy is passed through a laser.
The MRI machine can measure the temperature inside the tumor. Doctors are able to watch a monitor showing the temperature rising. When the tumor is heated to the point of destruction, the laser is turned off. The whole process lasts about two and a half minutes.
FAITH LAPIDUS: Doctor Walser first used the MRI-guided laser procedure in June. The Mayo Clinic reported that he had successfully treated five patients by the middle of October.
Earlier this year, doctors at the Mayo Clinic in Minnesota used MRI-guided laser ablation to remove tumors of the prostate. Doctor David Woodrum has successfully treated seven prostate patients with the procedure. He says it provides for a less invasive and less traumatic experience.
The process is still being developed, but doctors say it could prove to be successful for treating most cancers in the body. The doctors say it should only be used on tumors that are less than five centimeters in size.
(MUSIC)BOB DOUGHTY: Malaria kills about one million people a year and sickens another two hundred fifty million. Most of the deaths are in young children in Africa. People become infected when they are bitten by mosquitoes carrying the malaria parasite⁸.
A new report estimates the possibility of ending malaria in countries that have the deadliest form of the disease. Researchers found that this could be possible in most parts of the world within ten to fifteen years. What it would require, they say, is reducing the spread of malaria by ninety percent from two thousand seven rates.
Women receive mosquito nets in Sesheke, Zambia, in September FAITH LAPIDUS: An international team created mathematical models and maps of areas where the disease is gone or almost gone. The report says malaria could be eliminated if countries are serious about using proven control measures like insecticides and bed nets.
The Bill and Melinda Gates Foundation partly financed the research. The study appears in The Lancet medical journal.
Some malaria experts expressed concern about giving too much attention to eliminating the disease. They say such a goal could take many years, if it is possible at all. The concern is that resources for controlling malaria could be lost if the money is spent instead on efforts to defeat it.
(MUSIC)BOB DOUGHTY: A new study shows that long, severe droughts may strike countries with large populations in the not-so-distant future. The study was made for America’s National Center for Atmospheric⁹ Research.
NCAR scientist Aiguo Dai led the research. It shows that drought conditions will threaten most of North and South America by the end of this century. The research found that large parts of Eurasia, Africa and Australia are also at risk. But places from Alaska to northern Europe may get more rainfall and snow. The findings appeared in the publication “Wiley Interdisciplinary Reviews: Climate Change.”
FAITH LAPIDUS: In the study, Mr. Dai examined rising temperatures linked to climate change. He says the higher temperatures probably will create increasingly dry conditions. He says these conditions will be seen across much of the world in the next thirty years.
The scientist also considered the possibility that drought could be much worse by the end of the century. At that time, he says, lack of moisture in many places could be as bad as or worse than any in modern time.
He made the predictions after looking at earlier studies and research. His study used modern proposals of possible conditions. It also employed twenty-two computer climate models and a list of drought conditions. The International Panel on Climate Change used twenty-two models in its two-thousand-seven report.
BOB DOUGHTY: Mr. Dai said he based the new predictions on the best current projections¹⁰ of carbon dioxide and other gases linked to climate change. The projections are estimates of future amounts of such greenhouse gases. He says many conditions will decide what actually happens.
The conditions include natural climate cycles and the amount of greenhouse gases that will be released into the air. Two good examples of such cycles are El Nino and La Nina. They are periodic events that change moisture levels in the atmosphere.
FAITH LAPIDUS: The study identified areas threatened with major drying in the future. They include much of Central and South America. Southeast Asia, large parts of southwest Asia, and most of Africa and Australia also will be affected¹¹. The research shows that drying in areas along the Mediterranean¹² Sea could also become intense.
Other areas were said to expect more moisture. They are much of Scandinavia, Russia, Canada and Alaska. The study shows that some areas of the Southern Hemisphere also may escape drought.
(MUSIC)BOB DOUGHTY: Do not waste food, and you will save energy. That is the message of scientists who say America wastes food energy equal to about three hundred fifty million barrels of oil a year. That represents about two percent of yearly energy usage in the United States.
Scientists Amanda Cuellar and Michael Webber work at The University of Texas at Austin. They reported the findings last month in the journal “Environmental Science & Technology.”
Mr. Webber says a lot more energy goes into food than people think. His report estimates that, three years ago, between eight and sixteen percent of all energy used in the United States supported food production.
FAITH LAPIDUS: The Texas researchers estimated the energy intensity¹³ of preparing food from agriculture, transportation, processing and food sales. They also included the energy intensity of storing and preparing food. The researchers measured food intensity in British thermal¹⁴ units, better known as BTUs. A BTU is the amount of heat energy needed to raise the temperature of about one-half kilogram of a substance by one degree Fahrenheit¹⁵.
The scientists say they used information provided by the United States government from nineteen-ninety-five. At that time, the government estimated that twenty-seven percent of food for human consumption was wasted.
BOB DOUGHTY: The report said the most wasted foods were dairy products, eggs, fats, grains and oils. Among the least wasted were dry beans, fish, lentils, meat, poultry¹⁶, peanuts, peas and tree nuts.
Last year, a report in the journal PLoS One considered the environmental effects of wasting food. Scientists from the National Institute of Diabetes¹⁷ and Digestive and Kidney Diseases measured the energy content of America’s wasted food. They found that American waste of food per person has risen by about fifty percent since nineteen seventy-four.
(MUSIC)FAITH LAPIDUS: This SCIENCE IN THE NEWS was written by Jerilyn Watson, Caty Weaver¹⁸ and June Simms, who was also our producer. I’m Faith Lapidus.
BOB DOUGHTY: And I’m Bob Doughty. Listen again next week for more news about science in Special English on the Voice of America.

1 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。

2 malaria   

n.疟疾

参考例句：

• He had frequent attacks of malaria.他常患疟疾。
• Malaria is a kind of serious malady.疟疾是一种严重的疾病。

3 savings   

n.存款，储蓄

参考例句：

• I can't afford the vacation,for it would eat up my savings.我度不起假，那样会把我的积蓄用光的。
• By this time he had used up all his savings.到这时，他的存款已全部用完。

4 tumor   

n.（肿）瘤，肿块(英)tumour

参考例句：

• He was died of a malignant tumor.他死于恶性肿瘤。
• The surgeons irradiated the tumor.外科医生用X射线照射那个肿瘤。

5 spine   

n.脊柱，脊椎；(动植物的)刺；书脊

参考例句：

• He broke his spine in a fall from a horse.他从马上跌下摔断了脊梁骨。
• His spine developed a slight curve.他的脊柱有点弯曲。

6 expectancy   

n.期望，预期，（根据概率统计求得）预期数额

参考例句：

• Japanese people have a very high life expectancy.日本人的平均寿命非常长。
• The atomosphere of tense expectancy sobered everyone.这种期望的紧张气氛使每个人变得严肃起来。

7 interventional   

[医]介入的； 干涉的

参考例句：

• AM Contrast Nephropathy: What the Interventional Cardiologist Should Know and Do? 对比剂肾病：介入医师必须想到的和做到的是什么？ 来自互联网
• This article reviews some progresses in interventional therapy of liver cancer. 本文就肝癌介入治疗方面的研究进展简要综述。 来自互联网

8 parasite   

n.寄生虫；寄生菌；食客

参考例句：

• The lazy man was a parasite on his family.那懒汉是家里的寄生虫。
• I don't want to be a parasite.I must earn my own way in life.我不想做寄生虫，我要自己养活自己。

9 atmospheric   

adj.大气的，空气的；大气层的；大气所引起的

参考例句：

• Sea surface temperatures and atmospheric circulation are strongly coupled.海洋表面温度与大气环流是密切相关的。
• Clouds return radiant energy to the surface primarily via the atmospheric window.云主要通过大气窗区向地表辐射能量。

10 projections   

预测( projection的名词复数 )； 投影； 投掷； 突起物

参考例句：

• Their sales projections are a total thumbsuck. 他们的销售量预测纯属估计。
• The council has revised its projections of funding requirements upwards. 地方议会调高了对资金需求的预测。

11 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。

12 Mediterranean   

adj.地中海的；地中海沿岸的

参考例句：

• The houses are Mediterranean in character.这些房子都属地中海风格。
• Gibraltar is the key to the Mediterranean.直布罗陀是地中海的要冲。

13 intensity   

n.强烈，剧烈；强度；烈度

参考例句：

• I didn't realize the intensity of people's feelings on this issue.我没有意识到这一问题能引起群情激奋。
• The strike is growing in intensity.罢工日益加剧。

14 thermal   

adj.热的，由热造成的；保暖的

参考例句：

• They will build another thermal power station.他们要另外建一座热能发电站。
• Volcanic activity has created thermal springs and boiling mud pools.火山活动产生了温泉和沸腾的泥浆池。

15 Fahrenheit   

n./adj.华氏温度；华氏温度计(的)

参考例句：

• He was asked for the boiling point of water in Fahrenheit.他被问到水的沸点是华氏多少度。
• The thermometer reads 80 degrees Fahrenheit.寒暑表指出华氏80度。

16 poultry   

n.家禽，禽肉

参考例句：

• There is not much poultry in the shops. 商店里禽肉不太多。
• What do you feed the poultry on? 你们用什么饲料喂养家禽?

17 diabetes   

n.糖尿病

参考例句：

• In case of diabetes, physicians advise against the use of sugar.对于糖尿病患者，医生告诫他们不要吃糖。
• Diabetes is caused by a fault in the insulin production of the body.糖尿病是由体內胰岛素分泌失调引起的。

18 weaver   

n.织布工；编织者

参考例句：

• She was a fast weaver and the cloth was very good.她织布织得很快，而且布的质量很好。
• The eager weaver did not notice my confusion.热心的纺织工人没有注意到我的狼狈相。