VOA慢速英语2009-SCIENCE IN THE NEWS - Project Aims to Help S（在线收听）

VOICE ONE:

This is SCIENCE IN THE NEWS in VOA Special English. I'm Barbara Klein.

VOICE TWO:

And I'm Bob Doughty. On our show this week, we will tell about what is being called the world's largest tornado experiment. We also will tell how a job loss can affect your health. And, we tell about a simple way to save lives.

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VOICE ONE:

Tornadoes are one of the most violent weather events on Earth. Each year, the severe winds of tornadoes kill many people. The storms have been known to carry homes, cars and trees from one plane to another. And they can also destroy anything in their path.

VOICE TWO:

A tornado is a violently turning tube of air suspended from a thick cloud. It extends from a thunderstorm in the sky down to the ground. The shape is like a funnel: wide at the top, narrower at the bottom.

Tornadoes form when winds blowing in different directions meet in the cloud and begin to turn in circles. Warm air rising from below causes the wind tube to reach toward the ground. Because of their circular movement, these severe windstorms are also known as twisters.

VOICE ONE:

Tornadoes have been observed on every continent except Antarctica. But weather experts say they are most common is the United States. Each year, the United States has more than one thousand tornadoes.

These storms can happen any time of the year. But most happen from late winter to the middle of summer. There is a second high season in November.

During spring, warm air moves north and mixes with cold air remaining from winter. In November, the opposite happens. Cold weather moves south and combines with the last of the warm air from summer.

VOICE TWO:

Tornadoes can strike with little or no warning. Weather experts operate warning systems to tell people about possible tornadoes. But the storms often move too fast for people to flee. Last year, tornadoes killed more than one hundred people in the United States.

Most injuries happen when flying objects hit people. Experts say the best place to be is in a small room, without windows, in the middle of the lowest part of a building.

VOICE ONE:
　
Vortex2 equipment

Last month, American scientists began work on a project aimed at improving the ability to predict tornadoes. The project is said to be the largest tornado study in history. It is called Verification of the Origins of Rotation in Tornadoes Experiment Two. The shorter name is VORTEX2.

The project covers an area of nearly one thousand five hundred kilometers in the central United States. This area, from west Texas to southwest Minnesota, is where the most violent tornadoes usually happen. It is known as "Tornado Alley."

VOICE TWO:

VORTEX2 involves a team of nearly one hundred people, many of them scientists. They are using radars and other equipment to learn more about how, why and where tornadoes form. The team is using forty cars and trucks to chase tornadoes, dropping measuring instruments in their paths. In addition, unmanned aircraft are collecting information from inside storms.

The project costs more than eleven million dollars. Most of the money is coming from America's National Science Foundation.

VOICE ONE:

The first Vortex project took place in nineteen ninety-four and nineteen ninety-five. The results helped scientists better understand supercells. They are the severe thunderstorms that produce the most deadly and destructive tornadoes. This time, scientists hope to learn more about the formation, wind speed and shape of tornadoes.

The study is to continue through June thirteenth. A second part of the study is planned for early next year. You can follow reports from scientists on the project at tornadoscientists.blogspot.com.

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VOICE TWO:

You are listening to the VOA Special English program SCIENCE IN THE NEWS. With Barbara Klein, I'm Bob Doughty in Washington.

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Millions of Americans have lost their jobs as a result of the current recession. A new study shows that losing your job can increase your risk of developing health problems. These include heart disease, heart attack, stroke, diabetes and high blood pressure.

Earlier studies have shown a link between job loss and worsened health. However it was unclear to researchers whether unemployment caused poor health, or whether poor health led to job loss. The new study sought to discover the answer to this.

VOICE ONE:

Kate Strully carried out the study while she was at the Harvard School of Public Health. Currently, Miz Strully is a sociologist at State University of New York. She examined information from the United States Panel of Study of Income Dynamics. This study asks people across the country each year about their health and employment.

Miz Strully examined information about more than eight thousand people. They were questioned in nineteen ninety-nine, two thousand one and two thousand three. Miz Strully noted whether the subjects were employed and then looked at their health eighteen months later.

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The sociologist says she was looking for individuals who reported becoming jobless for reasons out of their control, such as a factory closing. She found that such individuals who did not have health problems were eighty percent more likely to report a new health problem after losing their job.

The most common problems were high blood pressure or other conditions linked to heart disease. Among all workers, the possibility of someone reporting fair or poor health rose forty-four percent after job loss and workplace closure.

The study's findings were reported in the publication Demography.

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VOICE ONE:
　
Hands-Only CPR

If a person's heart stops, would you know how to perform CPR? CPR, or cardiopulmonary resuscitation, can save a life and reduce the risk of brain damage from loss of oxygen. With traditional CPR, you give two breathes to force air into the lungs. Then you push hard on the chest thirty times. You repeat these two steps until the victim wakes up or medical help arrives.

But people may worry about getting sick from blowing into a stranger's mouth. Also, the training is easy to forget, especially during an emergency. And those without training may not do anything for fear that they will do something wrong.

VOICE TWO:

Last year, the American Heart Association reformed its guidelines for CPR. The group now calls for hands-only CPR for adults who suddenly collapse. Here is how it works.

A person has collapsed unconscious on the ground. The victim has lost color in the face and does not appear to be breathing. These are signs of cardiac arrest. This is the time to begin CPR.

Place your hands, one on top of the other, on the center of the chest. Push hard and fast. Aim for a rate of about one hundred compressions each minute. Chest compressions keep the blood flowing to the brain, heart and other organs.

VOICE ONE:

Guidelines from two thousand five said only untrained people should use hands-only CPR. Those with training were told to use traditional CPR. But now the heart association says everyone should use hands-only CPR unless they feel strong about their ability to do rescue breathing.

The rules were reformed after three studies showed that the hands-only method was just as effective as traditional CPR. Scientists say enough oxygen remains in a person's system for several minutes after breathing stops.

VOICE TWO:

But the experts say you should still use traditional CPR with a combination of breaths and compressions on babies and children. Traditional CPR should also be used for adults found already unconscious and not breathing normally. And traditional CPR should be used for any victims of drowning or collapse from breathing problems.

These are all examples where CPR with mouth-to-mouth breathing may be more helpful that hands-only CPR. Because there are many of these cases, people should still learn CPR with mouth-to-mouth.

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VOICE ONE:

This SCIENCE IN THE NEWS was written by Caty Weaver and Brianna Blake, who was also our producer. I'm Barbara Klein.

VOICE TWO:

And I'm Bob Doughty. Read and listen to our programs at voaspecialenglish.com. Listen again next week for more news about science in Special English on the Voice of America.