Alcohol and the Heart

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Alcohol and the Heart

Two new studies have added to the evidence that drinking a little alcohol each day is good for the heart. Earlier studies have shown that drinking a moderate amount of alcohol reduces the chances of suffering a heart attack or a stroke caused by thickening of the blood.

The new studies were published in the Journal of the American Medical Association. One group of researchers was from Beth Israel Deaconess Medical Center in Boston, Massachusetts. They questioned almost two-thousand patients at forty-five hospitals. All the patients had just suffered heart attacks. The researchers asked them how much alcohol they drank in the year before the heart attack. Those who had fewer than seven alcoholic drinks a week were considered light drinkers. Those who had more than seven drinks a week were considered moderate drinkers.

The researchers studied the patients' health for the next four years. At the end of that time, the light drinkers had a twenty-one percent lower chance of dying from a heart attack than those who never drank at all. The moderate drinkers had a thirty-two percent lower chance of dying than those who never drank. The drinkers survived mostly because they had fewer additional heart attacks.

The other study involved more than two-thousand older men and women. Their average age was seventy-four. Researchers from Emory University in Atlanta, Georgia asked them how much alcohol they drank. The researchers studied the health of these people for up to fourteen years. They found that those who had one or two drinks each day were twenty to fifty percent less likely to develop heart failure than those who did not drink.

Both studies found no difference in survival among people who drank beer, wine or liquor.

Arthur Klatsky is a heart doctor at the Kaiser Permanente Medical Center in Oakland, California. Doctor Klatsky said both studies strengthen the idea that drinking a small amount of alcohol each day can protect the heart. Alcohol thins the blood and prevents clots that block arteries. It also increases the so-called good cholesterol in the blood that helps keep arteries open.

However, other health risks have been linked to moderate drinking. And Doctor Klatsky said heavy alcohol drinking is a sure way to damage your health.

This VOA Special English SCIENCE REPORT was written by Nancy Steinbach.

African Elephants

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African Elephants

Scientists say African elephants that live in the forest and those that live in grasslands are different enough to be considered separate kinds, or species. Until now, scientists believed all African elephants were the same genetically. They have long recognized the clear differences between African and Asian elephants.

One genetic researcher said the difference between the two groups of African elephants is as large as the difference between a lion and a tiger. Researchers from the United States and Kenya announced the discovery in the publication Science.

They examined genetic differences in almost two-hundred African elephants in grasslands and forests. They collected tissue from more than twenty groups of elephants in the wild over a period of eight years. They did so by firing small sharp objects into the elephants. The darts removed small pieces of skin and then dropped to the ground.

The researchers examined the genetic material from the elephants’ skin. They found great differences between the African elephants living in the forest and those that live on the grasslands.

The grassland elephant has large ears and curving ivory tusks. People can see these elephants in zoos and in visits to Africa. The forest elephant is smaller and has round ears. Its tusks are straighter and longer. The ivory is slightly pink in color. The forest elephant is not often seen in the wild. Only one African forest elephant is in a zoo. It is in Paris, France.

The researchers say genetic differences show that the two kinds of African elephants began to develop into separate species more than two-million years ago. The research also shows that all grassland elephants are genetically the same. This means they all developed from one recent ancestor. The forest elephants, however, are genetically different from each other. This means that elephants in forest groups rarely mate and reproduce with members of other groups.

The researchers say that only about two-hundred-thousand African elephants live in the forests. These elephants face a greater threat to their survival than other elephants. The threats are from land development and other human activity. Scientists say it is important that the African forest elephant be recognized as a separate species so it can be protected.

This VOA Special English Science Report was written by Nancy Steinbach.

Lecture or Interactive Teaching? Old Issue, New Study

Lecture or Interactive Teaching? Old Issue, New Study

 01 June 2011

Photo: Getty Images/iStockphoto

College students in interactive classes score higher on tests than those in traditional lecture classes, according to a new study.

TO DOWNLOAD the MP3 of this story, click on the MP3 link in the upper right corner of the page. Double-click any word to find the definition in the Merriam-Webster Learner's Dictionary

This is the VOA Special English Education Report.
Professors have lectured for centuries. But how effective is lecturing to students compared to working with them?
A new study compared two classes of a beginning physics course at the University of British Columbia in Canada. There were more than two hundred sixty students in each section. Both were taught by popular and experienced professors.
The study took place for one week near the end of the year. One class continued to be taught in the traditional lecture style. The other professor was replaced by two teachers. They had little teaching experience but received training in interactive teaching methods. The training was led by Carl Wieman, a Nobel Prize-winning physicist who leads a science education program.
There was almost no lecturing. The teachers put the students in small groups to discuss and answer questions. They gave them readings and quizzes to finish before class so they would come prepared to discuss the material.
Professor Wieman says before the experiment with these and other activities, test scores for both classes were the same.


CARL WIEMAN: "There was a great deal of careful data collected showing how identical the two sections, these two large sections of the class were beforehand. And this focused very much on looking at exactly what could be learned with the different methods from the classroom experience, the time when you have the maximum instructor interaction, or face-to-face interaction time.”
Afterward, both classes took the same test. Students in the interactive class scored nearly twice as high as those in the traditional class. Attendance also increased that week.
Graduate student Ellen Schelew was one of the teachers. She says the methods they used are designed to encourage students to think like scientists.


ELLEN SCHELEW: "Their brains are turned on. They’re thinking hard and they’re really working through these problems. So even if they don’t have enough time to complete a given problem, they are prepared to learn from the instructor feedback that always follows groups’ tasks."
The study appeared in May in the journal Science. It seems to confirm earlier findings about lecturing to large classes. But some experts have criticized the way the study was done.
Both of the researchers who taught the class, Ms. Schelew and Louis Deslauriers, were also authors of the study. This could raise questions about whether their involvement might have influenced the results.
Professor Wieman is currently on leave from the University of British Columbia and the University of Colorado. He is the associate director for science in the White House Office of Science and Technology Policy.
He says research has shown better ways to teach based on evidence about how the brain learns. And he hopes more professors will learn that how someone teaches may be more important than who does the teaching.
And that's the VOA Special English Education Report. I'm Christopher Cruise.