Accessibility links

Our World Transcript November 27, 2004

This transcript is provided as a convience to users.

There may be slight differences between this text and the radio program as broadcast.

MUSIC (Minidisc): Establish and under

CHIMES: Straight ahead on "Our World" … a new risk for obesity ... a space-age material gets down-to-earth ... and a report from the World Conservation Congress

DALET: TEASE (Jhirad) (:12)
"The whole theme of this conference was People and Nature, Only One World. And I think there's really a trend in the future to look at people as the center of the environment, and the livelihood of people as being very important as well."

CHIMES: Those stories, plus the centennial of electronics. I'm Art Chimes. Welcome to VOA's science and technology magazine, "Our World."

MUSIC: Up to button

CHIMES: Thursday was one of our favorite national holidays here in the United States -- Thanksgiving. It's a holiday deeply associated with food -- with traditional favorites, especially a roast turkey, gracing millions of tables around the country. Many Americans, it's safe to say, ate too much on Thanksgiving.

The trouble is, too many Americans apparently eat too much too often. Many experts here consider obesity to be a very significant -- and growing -- public health problem. About one-third of the population is considered obese by the accepted medical definition. Obesity, or excessive overweight, is a well-documented cause of a number of health problems, including heart disease, diabetes, stroke, osteoarthritis and even some cancers. Now, a new study is the first to tie it to an irregular heartbeat, which can in turn cause stroke and heart failure. From Washington, VOA's David McAlary explains why that's signficant.

McALARY: Fifty-seven-year-old John Nagle, no longer a slender man, went to a hospital emergency room a few years ago fearing he was about to have a heart attack. But the reason for his visit was not chest pain.

/// NAGLE ACT ///

"When I first came to the hospital, there was shortness of breath, but no pain. That's when they found out that I had the irregular heartbeat."

/// END ACT ///

McALARY: Doctors call irregular heartbeat "atrial fibrillation." It is common and potentially serious, according to Harvard University Medical School physician Thomas Wang in Boston.

/// WANG ACT ///

"Atrial fibrillation is a major cause of stroke and heart failure and may also be related to an increased risk of death. It's an abnormal rhythm of the heart that is caused when the upper chambers of the heart beat in an uncoordinated and irregular fashion."

/// END ACT ///

McALARY: Prior studies have shown that advanced age, diabetes, high blood pressure, and heart disease increase the risk of atrial fibrillation. Now, Dr. Wang and colleagues have found that obesity is also a factor. The finding is based on data they extracted from ongoing research called the Framingham Heart Study.

/// 2nd WANG ACT ///

"What we found is that obesity was associated with an approximately 50-percent increase in the risk of developing atrial fibrillation."

/// END ACT ///

McALARY: The researchers came to this conclusion by tracking the health of more than five-thousand Framingham Heart Study participants, men and women, for about 14 years. Their average age was 57.

/// OPT /// McALARY: Dr. Wang's overweight patient, John Nagle, was not surprised to learn of the finding.

/// OPT /// 2nd NAGLE ACT ///

"My heart is really laboring to breathe walking up a flight of stairs or even up a slight hill, so the more weight I put on, I can tell the harder it is for the heart to work."

/// END ACT /// END OPT ///

McALARY: Why can obesity have an impact on heart rhythms? Again, Dr. Wang.

/// 3rd WANG ACT ///

"We speculate that this may be the result of the effects of obesity on the structure of the heart and on the chambers of the heart where this abnormal rhythm originates. Once you get atrial fibrillation, it may be very difficult for doctors to get you back into the normal rhythm. What that means for the patient is that the patient may be stuck with a lifetime of taking medications to protect against stroke and the other complications of atrial fibrillation."

/// END ACT ///

McALARY: The study appears in the Journal of the American Medical Association. In it, Dr. Wang and his colleagues say the prevalence of atrial fibrillation is expected to increase several-fold in the coming decades as the aging general population grows fatter. But they say that, just as obesity can be modified, so can the prospect of an irregular heartbeat.

CHIMES: Also this week, U.S. public health officials said a study published in March overestimated the number of Americans dying from obesity. The report projected that a rising death toll linked to obesity would -- as soon as next year -- make it the leading cause of preventable death in the US, overtaking smoking. The Centers for Disease Control and Prevention cited a statistical error in the earlier report by government scientists, but stressed that obesity continues to be a major public health problem and a leading cause of death.

The World Conservation Congress ended Thursday in Bangkok. It's the once-every-four-year-meeting of the World Conservation Union, a group that includes some 200 states and government agencies, plus hundreds of NGOs and some 10-thousand scientists and other environmental experts.

At the group's week-long meeting, delegates approved a resolution calling for a moratorium on the release of genetically-modified organisms until their safety can be demonstrated "beyond reasonable doubt."

To bring us up to date on the controversy over genetic engineering, I spoke with Dr. David Jhirad, who was attending the World Conservation Congress as vice president for research at the World Resources Institute, a Washington-based environmental policy group. Dr. Jhirad told me that some delegates felt the call for a moratorium on genetically-modified organisms -- known as GMOs -- was premature.

JHIRAD: A minority feel that this issue is too important and needs a lot more scientific analysis, and we need to look at the economic benefits of GMOs as well as the risks. You know, there needs to be a rational calculation of risks and benefits. And some of us feel that that needs to be done -- that we don't really know enough to just have an outright ban of the kind that was agreed upon by the majority.

CHIMES: What have been some of the other big issues at this event?

JHIRAD: One very big issue, of course, has been climate change. That's kind of dominated the discussion because as you know there was a new report released on the Arctic and the accelerated melting of the ice in the Arctic region and the polar ice caps, and the fact that global warming is happening a lot faster up there, and it's affecting both wildlife and the people who live there, many of the indigenous people are beginning to feel their way of life and their economic sustenance is being threatened by climate change. You know, they've had the warmest decade ever in memory. So that was a big issue, climate change. But not just the science of climate change, but its impact on people and the impact on the livelihoods of people. So one very big issue was that poor populations, native populations are most vulnerable to climate change, and that seemed to be something playing out at different points in the conference.

CHIMES: This link between poverty and the environment is something that I think has not gotten a great deal of attention in the past. Do you see this as part of a trend focusing more on that, and is it also a strategic move?

JHIRAD: Very good question, yes. The whole theme of this conference was People and Nature, Only One World. And I think there's really a trend in the future to look at people as the center of the environment, and the livlihood of people as being very important as well, and seeing protecting the environment as kind of protecting the natural wealth of the systems that provide people with their living -- you know, food and agriculture, fisheries and forest. All of these are natural resources that should be used wisely so that people can progress economically and we could move toward eradicating poverty while protecting the environment. And that's really a trend that most people are embracing right now.

CHIMES: Is there a danger that when you make that sort of calculus that you are going to look at a "minor" species and decide, well, that's expendible because we need to expand the farmland to feed the people?

JHIRAD: That's certainly a tension, and you just put your finger on a conflict that needs to be resolved between some groups that want to just fence off the land and keep people out and others who feel that people should have the right to make decisions about their own land and the area that they live in, the forest that they live in and the fisheries and so forth. That in fact was one of the big tensions in the conference, was between the rights of what are known as indigenous populations and econsystems. You know, the old idea of fencing everything off and keeping the people out versus making people, you know, a central part of the picture. The key point is who really represents indigenous peoples, and most of the indigenous groups that are at the conference want to have a voice of their own; they want to represent themselves. And they believe in protecting forests and fisheries and dry lands and so forth, but they also believe, quite rightly, that they need to make a living.

CHIMES: You describe that as a "tension." Did anybody's mind get changed?

JHIRAD: That's a very good question. My sense is that this is going to take some work. I don't think that one conference can change minds, but I do think that it can set the stage for us, all of us on different sides of this issue, to work together, to make sure everyone has access to information, everyone participates and that we have legal redress, so that information, participation and justice are kind of at the core of all this.

CHIMES: David Jhirad of the World Resources Institute spoke to us from Bangkok where he was attending the World Conservation Congress.

As we reported on Our World, parts of the northeast United States were inundated a few months ago with billions and billions of cicadas -- bugs about the size of my thumb that crawl out of the ground every 17 years, fly around looking for mates, lay eggs and die.

They are slow moving, easy targets for predators. Their defense, says researcher Louie Yang, is in their sheer numbers and a concept called "predator satiation."

YANG (:16): "They occur in such magnitudes, at such densities and so suddenly, that their predators are unable to eat them all. And a large proportion of them escape predation entirely and just simply die. They die of natural causes."

CHIMES: Mr. Yang, a graduate student at the University of California/Davis, has published a paper in this week's edition of the journal "Science" on the ecological impact of all those uneaten cicadas. The life cycle of the cicada has interested many researchers, but Mr. Yang's work starts where the other scientists' leave off.

YANG (:07): "We know quite a bit about what happens to cicadas while they're still alive. But I think there's some interesting ecology that happens after they die."

CHIMES: As dead cicadas fall to the ground, they decompose and their nutrients enter the ecosystem. The sudden addition of all those nutrients is known as a "resource pulse."

YANG (:11): "That results in really explosive plant growth with a lot of indirect effects from that plant growth -- mammals are eating the seeds of those plants and a lot of things happen as a result."

CHIMES: In experiments, Mr. Yang found cicadas caused substantial enrichment of the soil, with plants growing larger seeds in areas fertilized by cicadas. That, in turn, can help plants reproduce. Which, in a sense, is ironic, or maybe appropriate, since during the 17 years that they live undeground, cicadas feed on plant roots.

Cicadas may be an unusual event in limited geographic areas, but Louie Yang says his research demonstrates that even a rare "resource pulse" like a once-in-17-years cicada emergence can have a significant impact on the local environment, and he says it illustrates the way above- and below-ground ecosystems can interact.

Aerogel is an exotic material developed just a few years ago. It's been used by NASA to capture comet samples and interplanetary dust. It weighs almost nothing -- a piece of aerogel is 99.8 percent air. Although it was first developed in the 1930s, it took decades to make its way into space, and now this innovative technology is finding its way into more down-to-earth uses -- as an insulating material that could cut down on home heating costs and save on construction materials. The Great Lakes Radio Consortium's Katherine Glover reports.

(Transcrpt of Glover report not available.)

CHIMES: The Great Lakes Radio Consortium is a production of Michigan Radio, with support from the Joyce Foundation, and the U.S. Department of Agriculture.

NASA's SWIFT gamma ray observatory finally rocketed into orbit last Saturday after a series of launch delays. The international program is designed to learn more about mysterious bursts of gamma rays that happen several times a day and can last up to a few minutes, but sometimes are over in a fraction of a second.

SWIFT mission operations director John Nousek of Pennsylvania State University says the satellite was designed to very quickly detect a gamma ray burst as it begins, and then spin around to focus on the event in progress and its afterglow in all the necessary wavelengths.

NOUSEK (:21): "SWIFT has this tremendous advantage, and it in fact, that was the whole concept of SWIFT of building these all in together, so the amount of latency we have is basically about 20 seconds between when the gamma ray burst occurs and one the satellite finishes analyzing its data set. From a scientist's point of view, this is exactly what you are looking for to make progress in a new field."

CHIMES: The gamma ray bursts that SWIFT will study are the most powerful explosions in the Universe. Scientists don't know what causes them. Theories include explosions that give birth to Black Holes and the collisions of neutron stars. SWIFT's instruments may help scientists in their effort to sort that out.

Time to dig in for Our World's Website of the Week ... and I do mean dig in, because our subject this week is archaeology. Professional archaeologists find out about the latest developments in their field by reading scholarly journals. For the rest of us, a good place to start is

The website is an outgrowth of Archaeology magazine, which has reported on the unearthing of relics from the ancient world for more than half a century. Executive Editor Mark Rose explains that the website went online around 1996, originally for promotional reasons, but since then it's taken on a life of its own.

ROSE (:09): "When we started the website it was largely just to increase awareness of the magazine. At this point it's surpassed that by far."

CHIMES: Now, the website not only has content from the magazine, but much more. The magazine comes out just six times a year, so the online version can be much more timely, with the latest archaeology news, plus lots of web-only content. Webmaster Amélie Walker highlights other features unique to the website, including Interactive Digs, where you can follow the daily progress of an archaeological exploration.

WALKER (:20): "It's something that can't really be done in the print magazine. It's very different, it's basically from the field, what they're finding, what they think it means, more of how archaeology really works in the field rather than just a finalized report. ... IN THE MAGAZINE"

CHIMES: allows you to ask questions directly to the archaeologists, and Ms. Walker says the Interactive Digs are especially popular with students.

The ancient world is never very far, it seems, from the popular culture. Just this week Hollywood premiered the latest Oliver Stone film based on the life of Alexander the Great. editor Mark Rose says films like that send visitors to his site for a reality check.

ROSE (:15): "People come to our site because they see that it's a reliable source of information. If they want to go behind the ideas or stories that are in popular culture, they can get sources here, they can get the real story here."

CHIMES: And you can discover the past through the latest online technology at, or get the link from our site,

One hundred years ago this month, the electronic age was born with a British patent application. VOA's Mike O'Sullivan looks back on the contribution of John Ambrose Fleming, developer of the vacuum tube. His pioneering work was recalled at a recent scientific conference in Los Angeles.

O'SULLIAN: It was November 1904 when Mr. Fleming filed his patent application for a device he called an "oscillation valve." It was based on Thomas Edison's incandescent lamp, which had a filament in a glass bulb that had been evacuated of air. The filament glowed when electricity passed through it.

Physicist Fred Dylla of the Jefferson Lab in Newport News, Virginia, says Mr. Fleming added a metal plate with a positive electric charge, transforming the light bulb into a device that regulates currents.

/// DYLLA ACT ///

"What we call in the U.S. the vacuum tube. And the vacuum tube became the first component of what was to become the electronics industry, the basis for radio and radio communications, and then television. And this was the workhorse component of that industry until it was supplanted by the transistor."

/// END ACT ///

O'SULLIAN: The transistor was developed in 1947, followed by the integrated circuit or chip, tiny clusters of transistors that form the basis for most modern electronics.

Vacuum tubes still have a place in some electrical devices, such as microwave ovens. And the cathode-ray tube still provides the viewing screen for many computers and televisions. But most electronic devices, from digital watches to computers, operate by using silicon chips.

/// OPT ///

An organization once called the American Vacuum Society, now simply known as AVS, brings together thousands of engineers and scientists to discuss developments in electronics. Mr. Dylla says there are electrical and mechanical engineers and physicists.

/// 2ND DYLLA ACT ///

"And even biophysicists and biochemists, because we are now learning to graft very simple biological organic molecules onto an inorganic semiconductor chip to make sensors that will have some use for us in medicine."

/// END ACT ///

O'SULLIAN: A new industry has grown up to support the companies that fabricate components, which are made in clean, often air-free environments. Allen Demetrius is executive vice president of the Kurt Lesker Company, which makes vacuum devices.


"When you're talking about integrated circuits, you're talking about depositing materials at the atomic or molecular level. And when you get down into that type of process, you need a pristine environment, where any contamination would be detrimental to those processes. So you create an environment that is essentially void of all contamination."

/// END OPT - END ACT ///

O'SULLIAN: Development scientist Mike Skegg of Omicron Nanotechnolgies says the new microelectronics industry brings its own set of problems. His company makes instruments that locate flaws on the surface of chips and other miniature devices.

/// SKEGG ACT ///

"The smaller the electronics get, the more perfect it's all got to be."

/// END ACT ///

O'SULLIAN: Physicist Fred Dylla says the early 20th century inventor John Ambrose Fleming might be overwhelmed by the range of instruments and the pace of change today in the industry he helped create. There is a new generation of electronic chips every year and a half. Consumer computers double in speed in about the same time span. And chips are found in nearly every household appliance. But Mr. Dylla says the British engineer would have recognized the principles of modern electronics, which are the same as those that led to his "oscillation valve" a century ago. (signed)

MINIDISC: Closing theme, estab, then under

CHIMES: That's our show for this week. If you've got a question about science, technology, health or the environment, we'd like to answer it. And we've got a VOA gift for you -- IF we use your question on the program. Email us at Ourworld is all one word. Or write us at -

Our World
Voice of America
Washington, DC 20237 USA.

Our World is edited by Rob Sivak. Our technical director this week is Gary Spizler. And this is Art Chimes, inviting you to join us online at or on your radio next Saturday and Sunday as we check out the latest in science and Our World.

MUSIC: Theme up