Study of Centenarians / How Sleep Improves Learning / New York Requires Abortion Training for Some New Doctors
This is Sarah Long. And this is Bob Doughty with SCIENCE IN THE NEWS, a VOA Special English program about recent developments in science. Today, we tell about people who live to be one-hundred years old. We tell about how sleep improves learning. We tell about required training for some doctors in New York City. And we tell about a plan to bury nuclear waste in the state of Nevada.
Scientists are trying to find out how some people live to be one-hundred years old and older. They say the brothers and sisters of people who are at least one-hundred years old have a much greater chance of reaching that age than the general population.
Thomas Perls of the Boston University School of Medicine in Massachusetts led the study. He and other researchers studied the family health histories of more than four-hundred families with at least one member who to lived be one-hundred. People who are at least one-hundred years old are called centenarians.
The researchers compared the death rates of the brothers and sisters in the study with the death rates for Americans born in nineteen-hundred. The researchers said the brothers of centenarians were seventeen times more likely to reach one-hundred years old, compared with the general population. The sisters were eight times more likely to reach that age.
There are currently about fifty-thousand centenarians in the United States. Doctor Perls said about eighty-five percent of them are women. Fifteen-percent are men. However, the men are in better physical condition than the women. He said the centenarian men have fewer diseases than the women and are more independent.
Researchers believe successful aging depends on many things, including genes. They believe centenarians may have genes that protect them against deadly diseases and enable them to live longer. They have not identified those genes. But they say they have found an area on one chromosome where such anti-aging genes may exist. The findings of the study were published in the Proceedings of the National Academy of Sciences.
American scientists have discovered a good reason to sleep a little longer in the morning. The scientists found that a little extra sleep helps people learn better. They demonstrated that people who learn a new skill, and then sleep well, are better at performing the skill the next day. The publication Neuron reported their findings.
Matthew Walker of Harvard University in Cambridge, Massachusetts and his team studied the effects of sleep on the ability to learn to do simple skills. They tested sixty-two people who carried out a number of small experiments. The people were trained to perform a simple skill with their fingers. They were asked to push a series of numbers on a computer keyboard as quickly as possible. They used the hand they do not normally use for such activities.
The people were trained in the morning, and then tested twelve hours later. The scientists found that their speed and performance did not improve greatly. Yet the results were different when the people were trained at night and tested the next day. After a good night's sleep, their performance improved by about twenty percent.
The researchers looked closely at the sleep activity of the people in the study. They found the improvement seemed to be directly linked to a kind of sleep at the end of a person's normal sleeping period. Doctor Walker says this is the kind of sleep that many people do not experience if they get up early in the morning.
The findings could help musicians, doctors or anyone else who is learning difficult skills that have to be repeated. The findings may help answer other questions, such as why babies sleep so much. Doctor Walker says the intensity of learning new skills and information may increase the brain's need for many hours of sleep.
New York City has changed its policy for training new doctors to perform operations to end unwanted pregnancies. Starting this month, New York's public hospital system requires that doctors training to care for women learn how to perform abortions.
The training will include the latest methods to end unwanted pregnancies, including use of a new pill. Doctors who oppose abortion may refuse the training for moral or religious reasons.
No other American city requires that doctors who treat women receive abortion training as part of their advanced education.
The organization Planned Parenthood says more than one-million American women have abortions each year. Officials say that abortion is one of the most common kinds of operations performed in the United States.
However, experts say eighty-four percent of local areas in the United States have no doctors trained to provide abortions. They say the lack of such doctors forces many women to travel more than eighty kilometers to find a doctor who will perform an abortion.
Experts say medical training programs that offer abortion have increased around the country in recent years. Women's rights activists say the new policy in New York's public hospitals may cause other hospitals to require doctors who treat women to have abortion training. They also hope that the training will increase the number of doctors able to perform the operation around the country. However, anti-abortion activists are opposed to the operation because they say abortions kill unborn children. Some activists have threatened doctors who perform the operations.
One New York anti-abortion group warned that there would be severe results when doctors trained in New York begin to perform abortions around the country.
President Bush has approved a project to bury nuclear waste material under Yucca Mountain in the state of Nevada. The project calls for burying more than seventy-thousand tons of radioactive nuclear waste material.
The material includes used nuclear fuel from power centers and waste from the production of nuclear weapons. The waste is now stored at more than one-hundred-thirty power centers in almost forty states. However, these power centers have little storage space left.
The federal government owns Yucca Mountain. No one lives there. It is in an extremely dry area more than one-hundred-forty-five kilometers northwest of Las Vegas, Nevada.
The dispute about burying nuclear waste under Yucca Mountain has continued for twenty years. Bush Administration officials say the nuclear waste burial project is scientifically acceptable. They also say placing all of the country's nuclear waste in one place would help protect against terrorist attacks in other parts of the country. Supporters of the plan say it is important for the future of the nuclear power industry.
However, there is much opposition to the plan. Opponents include environmental groups and Nevada state officials. They say the area is near inactive volcanoes and has experienced earthquakes. Movements in the earth could spread the radioactive material. Opponents say the rock might not be able to hold the waste and keep it from entering water underground.
Opponents also say the dangerous nuclear waste would have to be transported by trucks and trains across about forty states. They fear accidents or threats from terrorists could endanger the population in many areas. Opponents are trying to block the plan through legal action in the courts.
Now the Energy Department must request and receive permission for the project from the Nuclear Regulatory Commission. This process could last for five years. The Energy Department must provide evidence about the safety of the project. Supporters of the project hope it will begin in two-thousand-ten. However, opponents say they will continue to fight against it.
This SCIENCE IN THE NEWS program was written by Cynthia Kirk, George Grow, Bob Brumfield and Jerilyn Watson. It was produced by Caty Weaver. This is Sarah Long. And this is Bob Doughty. Join us again next week for more news about science in Special English on the Voice of America.