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By Mario Ritter

Broadcast: Tuesday, August 01, 2006

This is the VOA Special English Agriculture Report.

Jiro Kawasaki, Japan's health minister, announces the end of the ban on U.S. beef

American beef is returning to Japan. The Japanese government last week ended a ban in place since January over concerns about mad cow disease.

Japanese officials recently inspected thirty-five beef processing centers in the United States. They said all but one met Japanese safety requirements.

The ban on beef led to threats in Congress of trade restrictions against Japan.

The Japanese were the top buyer of American beef. The government first banned shipments in December of two thousand three. That was when the United States reported its first case of mad cow disease -- bovine spongiform encephalopathy, or B.S.E.

The Japanese lifted their ban last December, but renewed it in January after the discovery of backbone material in a meat shipment.

In all, there have been three confirmed cases of B.S.E. in the United States. The first was in a Canadian-born cow in Washington state. Last year a cow in Texas was found to have B.S.E.. And in March of this year, a cow in Alabama tested positive for the disease.

About twenty nations continue to ban American beef; others restrict some kinds of cattle products. Japan accepts only beef from cattle twenty months of age or younger. Also, processors must remove backbones and other parts that experts say could spread the disease.

Eating infected meat products has been blamed for more than one hundred fifty deaths, mostly in Britain.

Agriculture Secretary Mike Johanns says "American beef is extremely safe."

The Japanese ended their ban one week after Mister Johanns announced reductions in the B.S.E. testing program. The program will now test about forty thousand animals a year. That is still ten times the level suggested by the World Animal Health Organization.

Since June of two thousand four, the Agriculture Department has tested an average of more than one thousand animals per day. Two years of testing found two cases of B.S.E. Mister Johanns noted that both animals were born before the United States banned feeding cattle protein to other cattle.

A seven-year government study estimated the most likely number of cases at between four and seven out of forty-two million adult cattle.

But critics say the United States should be testing more cattle, not fewer.

And that's the VOA Special English Agriculture Report, written by Mario Ritter. Transcripts and archives of our reports are at www.voaspecialenglish.com. I'm Steve Ember.

By Jill Moss

Broadcast: Tuesday, August 01, 2006

VOICE ONE:

This is SCIENCE IN THE NEWS in VOA Special English. I'm Bob Doughty.

VOICE TWO:

And I'm Pat Bodnar. This week -- thinking about artificial intelligence ...

VOICE ONE:

And technology that uses thought to control movement could offer hope to people with spinal cord injuries.

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VOICE ONE:

The animated face of a robot designed at Carnegie Mellon University for an artificial intelligence competition

Artificial intelligence is technology designed to perform jobs that require higher-level thinking skills. In other words, skills like those of human intelligence.

A.l. systems have many different uses. They are used in economics, to study things like stock market activity. They are used in medicine -- for example, to help doctors recognize disorders and choose the best treatments. And they are used in the military, to develop systems like self-guiding vehicles and so-called smart bombs that look for their targets.

Robotic systems with artificial intelligence can perform many industrial duties. These robots can also help doctors operate on patients. They can even pilot spacecraft.

VOICE TWO:

In the summer of nineteen fifty-six, a small group of scientists gathered in Hanover, New Hampshire. They discussed how to create computer programs and machines that could think the way humans do. The conference was proposed as a two-month study. It was called the Dartmouth Summer Research Project on Artificial Intelligence.

The idea of intelligent machines is ancient. But the name of the Dartmouth project marked the first known use of the term "artificial intelligence." So says the American Association for Artificial Intelligence.

Dartmouth College just marked the fiftieth anniversary of that summer study. In July the school held a conference called AI@50 to explore the next fifty years in artificial intelligence. Organizers say about one hundred seventy-five people attended the three-day event.

Young graduate students got to meet the two men often called the fathers of artificial intelligence: Marvin Minsky and John McCarthy. Fifty years ago, Mister Minsky was a junior fellow at Harvard University. Mister McCarthy was a professor of mathematics at Dartmouth. These two researchers, and two others, wrote a proposal for the summer research project. Mister McCarthy is the one credited for the name "artificial intelligence."

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VOICE ONE:

The organizers of the nineteen fifty-six conference based it on a theory. The idea was that every part of human intelligence could be described in such detail that a machine could be made to copy it.

James Moor is a philosophy professor at Dartmouth. He directed the AI@50 conference last month. Professor Moor says it is true that computers are being built that operate in some ways like the brain. These are known as neural net computers. But, he adds, machines are unlikely to fully capture all human emotions, feelings and creativity -- at least not anytime soon.

The professor says computers may never replace humans, but humans should expect to find more and more "smart machines." These devices could someday even be implanted in the body.

Research into artificial intelligence includes areas like learning, reasoning and action. The work brings together people from many different areas of expertise.

Yet progress with artificial intelligence has been slower than those scientists fifty years ago had hoped. For example, Professor Moor notes the continued difficulty to train computers to use and translate language. Using language correctly requires a knowledge of countless social and cultural situations and conditions.

So language is an area where humans can still consider themselves smarter than machines.

VOICE TWO:

Carey Heckman teaches in the philosophy and computer science departments at Dartmouth. He notes that artificial intelligence plays an important part in national security and anti-terrorism programs. For example, A.I. systems are used in collecting communications and recognizing faces in a crowd.

Uses like these incite debate about issues like government spying and loss of privacy. Artificial intelligence is not just fertile ground for science fiction writers. There are social and economic issues to consider as the technology spreads. Even just the idea of trying to get computers to think like humans is enough to frighten some people.

At the same time, A.I. research involves philosophical questions about intelligence and the mind. These questions relate to how humans work and think. Carey Heckman at Dartmouth says the more scientists learn about artificial intelligence, "the more we learn about ourselves."

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VOICE ONE:

You are listening to SCIENCE IN THE NEWS in VOA Special English.

Scientists and engineers have created all kinds of technology to make people's lives easier. This is true for disabled people as well. But what about those with severe spinal-cord injuries, who cannot move their arms or legs? A new device could make their lives easier, too. This may not be an example of artificial intelligence, but it is an example of what human intelligence can do with technology.

A report last month in Nature magazine described a study by a team led by researchers at Brown University in Rhode Island.

VOICE TWO:

Matthew Nagle, with a BrainGate sensor in his head, is assisted by Abraham Caplan of Cyberkinetics, the maker

For nine months, the researchers followed a twenty-five-year-old disabled man as he learned to move objects simply with thought. This ability was made possible by a small electronic device in his brain. The device is a neuromotor prosthesis called BrainGate. It measures four millimeters by four millimeters.

The BrainGate device acts as a brain-to-movement system. Doctors inserted it into the motor cortex, a part of the brain involved in controlling movements.

The man had suffered a spinal cord injury three years earlier. But the researchers found that nerve activity continued in his motor cortex. The team had not known for sure if movement signals would still be sent in this part of his brain.

The patient was paralyzed from the neck down as a result of a knife wound that cut his spinal cord. But with the BrainGate system, he was able to guide a computer cursor and control objects on the screen. He could open e-mail and play "Neural Pong," a simple video game.

The patient could also operate a television. He was able to perform these actions while speaking at the same time. He was even able to pick up small objects with a robotic arm.

VOICE ONE:

Nerve activity recorded by the BrainGate sensor is processed into movement commands. The system used in the study includes wires attached to the skull. These wires pass through the skin to carry nerve signals to computers and other equipment to process them.

After the report was written, the scientists added a second patient with spinal cord injury to the study, a man fifty-five years old.

Research with neuromotor prosthetics has also been done with monkeys.

Experts say the BrainGate system marks a big improvement in what is known as brain-computer interface technology.

Scientists say the device could one day control a wheelchair or prosthetic arms and legs. They say the device, if combined with a muscle movement system, might even return the use of paralyzed limbs.

But a lot more work is needed before any of this might be possible.

VOICE TWO:

A company called Cyberkinetics Neurotechnology Systems created the BrainGate device. Professors and students at Brown University formed Cyberkinetics in two thousand one. They based their work on research developed in the laboratory of neuroscientist John Donoghue. The government paid for much of the research.

Professor Donoghue has been working on the BrainGate technology for more than ten years. He is chief scientific officer at Cyberkinetics and helped lead the study published in Nature.

In a related paper, researchers at Stanford University say the device produces an even faster reaction when placed in a different area in the brain. They say it could someday be possible to communicate information at a rate equal to typing fifteen words per minute on a computer.

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VOICE TWO:

SCIENCE IN THE NEWS was written by Jill Moss and produced by Brianna Blake. Transcripts and archives of our shows are at www.voaspecialenglish.com. I'm Pat Bodnar.

VOICE ONE:

And I'm Bob Doughty. Our e-mail address is special@voanews.com. We hope you can join us again next week for more news about science in Special English on the Voice of America.

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