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Our World — 3 March 2007

This transcript is provided as a service; there may be some variation between it and the program as broadcast.

MUSIC: "Our World" theme

Straight ahead on "Our World," Do you believe your horoscope? A new report on science literacy ... Feeding the poor with urban farming ... and the strange world of nanotechnology ...

MAYNARD: "So the difference in scale, going from human scale down to the nanoscale, is the equivalent of taking the moon and putting the head of a pin on the moon"

How nano-scale research could help fight cancer and malaria, plus the hot topic of cold physics, and more. I'm Art Chimes. Welcome to VOA's science and technology magazine, "Our World."

Americans are becoming more scientifically literate, according to a new survey, but we still have a long way to go.

Researchers at Michigan State University found that in less than 20 years the scientifically literate portion of the population almost tripled, from 10 percent to 28 percent. They define scientific literacy as having enough science background to understand a newspaper article on a science topic.

Despite the big jump, twenty-eight percent may still not sound very high, but Michigan State professor Jon Miller says it's enough to place the United States at number two, behind Sweden, in a worldwide ranking of scientific literacy. One reason for the strong showing, he suggests, is that American universities are not as specialized as those elsewhere.

MILLER: "The United States is the only country in the world that requires its college students to have a year of general education, which means a year of science."

At many American universities, first-year students are required to take courses in science, history, and literature, before specializing in later years. That's not typical in many other countries, says Nick Allum of the University of Surrey in England.

ALLUM: "Yeah, it's very unlikely, indeed, that they would have any science courses. It would be almost impossible, I would say. And that's not unusual. And in fact the specialization in Britain occurs much earlier, even at [age] 16, where you only study three or four subjects. It's possibly to study only arts subjects from 16 onward."

Allum, and Miller before him, were among the researchers who addressed the question of scientific literacy at the recent meeting of the American Association for the Advancement of Science in San Francisco.

Another was Raymond Eve of the University of Texas, who described a survey he did several years ago when there were plans to build the Superconducting Super Collider, a very expensive giant atom smasher, which was eventually cancelled.

EVE: "I did a survey of both college students and the public and asked them were they in favor of funding it or not, but the interesting question was one that, down at the bottom said, what does the super collider do? And a very large percentage said, well, it knocks down missiles, doesn't it?"

Well, actually, no. The super collider had nothing to do with a missile defense system, except that both were controversial and both carried astronomical price tags.

Scientists often cite the interest in astrology as a symptom of scientific illiteracy. As the late Cornell University astronomer Carl Sagan used to point out, virtually every newspaper in the United States publishes a daily horoscope, but few if any have a daily astronomy column. What might be considered an alarming number of people claim that astrology is scientific, but as Nick Allum of the University of Surrey points out, maybe they're confusing astrology with astronomy. He conducted a survey in Europe and got very different results, depending on whether he asked about "astrology" or "horoscopes."

ALLUM: "And sure enough we find only about 10 percent of people think horoscopes are very scientific — although that's rather a high proportion in some ways — compared with about 25-30 percent thinking the same about astrology."

Whatever the exact percentage, a lot of people put their faith in astrology, or at least have an interest in it and other pseudosciences. One scholar in the field, Susan Losh of Florida State University, suggests that a horoscope may provide answers to questions about life and love — questions that science doesn't even try to answer.

LOSH: "I think what a lot of what we call pseudoscience speaks to things that science does not speak to: the meaning of life, the uncertainty of life. So I really think that issues of, can I make it through life unscathed? What's going to happen to me next week? I mean, science doesn't tackle any of these things, but a lot of features of pseudoscience do."

Researchers say that among the weakest areas in Americans' understanding of science are evolution and biology. Michigan State University professor Jon Miller says that may be because acceptance of science in those areas is more personal and more likely to conflict with deeply held personal or religious views.

MILLER: "It's very clear now that you cannot both accept modern genomics and think that Adam and Eve are your distant relatives."

Miller's survey found that almost 30 percent of Americans are now scientifically literate. But, he said, we should take no pride in a finding that 70 percent of Americans can't understand the science stories in today's news.

The AAAS conference is a place where some of the world's leading experts come to discuss the hot topics in science. And for some of them, cold is one of the hottest topics. Now, if you live near the equator, you may have one idea of cold. If you live in the arctic, cold is something else entirely. But for low-temperature physicists, cold means close to absolute zero, around minus 273 degrees celsius. And down at those temperatures, materials behave strangely, and open up whole new avenues of theoretical research and practical applications. From the AAAS meeting in San Francisco and Boulder, Colorado, Shelley Schlender reports.

DOCUMENTARY SOUNDTRACK: "Using liquid oxygen, they brought down the temperature of the hydrogen gas to minus 200 degrees…."

SCHLENDER: When 19th century scientists first tried to liquefy oxygen, it seemed an impossible task. At the annual meeting of the American Association for the Advancement of Science, the AAAS, the audience got a glimpse of that historic drama, in a sneak preview of a documentary titled, Absolute Zero. It shows the challenges these scientists overcame to liquefy hydrogen . . .

DOCUMENTARY: "At minus 250 degrees, he had produced the coldest liquid on earth and come closer to absolute zero than anyone else."

SCHLENDER: And later, helium . . . .

DOCUMENTARY: "They had reached minus 268 degrees centigrade, just five degrees above absolute zero."

SCHLENDER: Those discoveries a century ago led to the refrigeration technologies that produce quick-frozen peas and liquefied oxygen for rocket fuel. Super cold helps in the production of microchips and fast computers. More applications are up ahead, thanks to researchers who study supercold things.

KASEVICH: "There was a huge factor of precision that was tantalizing and out there for us to go out there and grab."

SCHLENDER: Stanford professor Mark Kasevich says the sensitivity of instruments that include super cold fluids helps people spot subtle changes to the earth that can hint at minerals, such as diamonds, plus oil deposits.

KASEVICH: "We think we could be 10 or 100 times better than the existing technology, and that should help you find these oil and mineral deposits, that much quicker."

SCHLENDER: Super-cooling lets scientists study fundamental principles. For instance, University of California-Berkeley scientist Richard Packard says, super-cooled helium seems to defy the way that gravity normally forces water to flow. Take water in a toilet tank.

PACKARD: "What will happen. (TOILET FLUSHING SOUND) Don't you love sound effects? Crack me up!"

SCHLENDER: Things change with super cooled, fluid helium.

PACKARD: "It doesn't flush like a toilet, the fluid should oscillate back and forth, and in fact the frequencies are in the audio regime. So that would be: (WHINE) The fluid never goes through. It just goes back and forth."

SCHLENDER: This superfluid whistle is so sensitive, it may lead to enhanced earthquake studies and better Global Positioning Systems.

University of Colorado physicist Heather Lewandowski says that scientists also use cold temperatures to put their experiments in a kind of slow motion.

LEWANDOWSKI: "Why do we want them cold? Usually, cold really means slow. If you have an experiment, let's say it's about a meter long, you're only going to have a millisecond or so to really interrogate that and study that molecule before it zips across your experiment. Now, if you cool down these molecules, you have a much longer time to interrogate the molecule and thus you can more precisely measure things about the molecular system. We really want molecules because of their complex nature, and cold so we simplify things and study them for a long time."

SCHLENDER: For twenty years, Scientists have studied cold atoms. Lewandowski is looking at a newer frontier . . . super-cooled molecules. Because they're more complex, they're harder to catch in action. But that complexity reveals more about chemical reactions, which may lead to better medicines. It also might produce faster quantum computers. The first step, Lewandowski says, is HOW to slow down a molecule.

SCHLENDER: Back at her lab at the University of Colorado, Lewandowski's team starts with molecules at a normal room temperature and pressure. They send these into a metal container that's about a cubic meter, and looks like a submarine hatch.

LEWANDOWSKI: "This is our vacuum chamber. This is where all of the magic happens. This is where we make the cold molecules and slow them down."

SCHLENDER: In the vacuum chamber, the molecules expand . . . which quickly cools them to nearly absolute zero.

Next, Lewandowski's team uses electric fields that gently slow the molecules, and chill them even more. She adds that molecules are too complex to get as cold as a simple atom. But they'll come close.

LEWANDOWSKI: "It's a few billionths of a degree above absolute zero."

SCHLENDER: As for cooling anything to absolute zero, Lewandowski says, don't hold your breath.

LEWANDOWSKI: "It's sort of impossible to get to absolute zero. There's always some little bit of motion left."

SCHLENDER: But in that fine-tuned range between slowing tiny bits of matter and stopping them entirely, Lewandowski says there's plenty to discover. For Our World, I'm Shelley Schlender in Boulder, Colorado.

Time again for our Website of the Week, when we showcase interesting and innovative online destinations.

This week we feature an online map service that's backed by nearly a century of mapmaking experience.

CARROLL: "The National Geographic MapMachine is a web-based, interactive atlas of the world that allows people to browse and explore very detailed street maps and political maps, but also physical maps and a variety of thematic maps, ranging from weather to population density to nature and conservation."

Allen Carroll is chief cartographer for the National Geographic Society, whose MapMachine is online at The easy-to-use maps feature a number of different ways of looking at your city, your country or your planet — from viewing high resolution satellite images to comparing one's earthquake risk...

CARROLL: "Maps can show, really, almost anything that is distributed geographically across the face of our planet, or other planets, for that matter. And that makes maps a really fascinating way of looking at the world. Maps symbolize and simplify and represent the world. And so hundreds, thousands, really endless characteristics can be chosen for a map."

If you want to find out more about the places represented on the map, just click on the link to a part of the site called "People & Places."

CARROLL: "For several hundred nations and U.S. states and provinces and cities and some parks, you can go to our site and find video clips and photographs and news articles and more."

There is, literally, a world of information at the National Geographic MapMachine, online at, or get the link from our site,

MUSIC: CPR (David Crosby) — "Map to Buried Treasure"

You don't need a map to listen to VOA's worldwide science and technology magazine, Our World. I'm Art Chimes in Washington.

Scientists say nanotechnology, which involves some of the smallest things on earth, could have a big impact in developing countries. And some of the bigge st benefits could come in improving health.

Nanotechnology refers to the ability to manipulate materials on the nanometer scale.

How small is that? A nanometer is one-billionth of a meter, something like the length of a line just 10 atoms long.

That's hard to grasp, so nanotech scientist Andrew Maynard explains it with an analogy. If you can imagine a child the size of the Moon...

MAYNARD: "... A tennis ball will be something like 50 nanometers in diameter. Or the head of a pin will be one nanometer in diameter. So the difference in scale, going from human scale down to the nanoscale, is the equivalent of taking the moon and putting the head of a pin on the moon."

Maynard is chief scientist at the Project on Emerging Nanotechnologies, part of the Woodrow Wilson Center in Washington. At a symposium this week, he said researchers have been using nanotechnology to create products like cosmetics and stain-resistant clothing. But some of the most promising uses of nanotechnology are in the health field.

In sub-Saharan Africa each year, malaria kills a million children under the age of five. A big part of the malaria challenge is correctly diagnosing patients. Often, anti-malaria drugs are given without a proper diagnosis, to people who may not have malaria. That's not only wasteful, it contributes to drug resistance. Peter Singer of the University of Toronto says a nanotechnology called quantum dots could make it much easier to correctly diagnose malaria, instead of using the traditional method of examining a patient's blood under a microscope.

SINGER: "The bottom line of this is that changing the infrastructure from moderate infrastructure like microscopes, to minimal infrastructure, like the quantum dots I was showing you, saves hundreds of thousands of lives for malaria. So this is a serious public health issue at stake, just from a diagnostic."

In addition to better diagnostics, nanotechnology could help in treating disease. For example, as Piotr Grodzinski of the U.S. National Cancer Institute points out, it could help make existing medicines more effective.

GRODZINSKI: "You can develop techniques which allow [doctors] to deliver the therapeutic drug or therapeutic treatment locally to the tumor site, and in many cases use much lower dose of the drug, and by that means cause lower side effects."

Advances in nanotechnology are coming out of labs in the usual advanced countries. But scientists in developing and emerging countries — China, India and Brazil, for example - are also involved. However, as program moderator Jeff Spieler of the U.S. Agency for International Development cautioned, it's still a big step getting those innovations to some of the world's poorest people.

SPIELER: "This to some extent will depend on how many of the new innovations will actually be coming from the laboratories of less developed countries, and then what is the likelihood of that these advances, even in those laboratories, will find their way into the indigenous populations of those countries and not be picked up by somebody else?"

Although nanotech experts stress the potential benefits from the new technology, they also concede that there are risks involved in working with these new nano materials. Andrew Maynard of the Woodrow Wilson Center acknowledged the uncertainties.

MAYNARD: "There are going to be a whole new set of risk issues we need to address, and that's going to require quite a substantial investment in new science to understand what those risks are, but also how to translate and transform that information into effective and safe ways of using the technologies."

Among those at risk could be workers involved in manufacturing new nano-scale materials, as well as consumers, such as those taking nano-based medicines.

At it's most basic, the heart in your chest is a pump. And when the heart is damaged and can't pump blood adequately, the rest of the body can't get the oxygen it needs — oxygen that is carried by the blood. The condition is called heart failure, or congestive heart failure, and its symptoms range from swelling in the hands and feet to fatigue to damage to internal organs. And as we hear from heath reporter Rose Hoban, a new study indicates heart failure can also affect a patient's mental health.

HOBAN: Close to half of patients diagnosed with heart failure will report being depressed, and of those people, about a third will experience serious depression. Now it appears that having depression can make heart failure worse. Psychologist James Blumenthal, from Duke University in Durham, North Carolina, led a study in which researchers surveyed several hundred cardiac patients about their mood:

BLUMENTHAL: "We were assessing for symptoms of depression, which involves feeling sad, being irritable, feeling worthless, feeling guilty, feeling easily fatigued, having disturbances of sleep and feeling that life wasn't worthwhile."

HOBAN: Blumenthal found that patients who reported many of these symptoms did worse than patients who didn't:

BLUMENTHAL: "We found that [patients with] elevated levels of depression were also more likely to die or be hospitalized, and that the increased risk of being in the hospital or dying was associated with depression over and above the severity of their cardiac condition."

HOBAN: Earlier studies have found similar results. What is unique about Blumenthal's work is that his researchers also took physiologic measurements of the patients' cardiac function. They found patients with more severe depression had increased levels of a protein created by damaged hearts. He says there are other physical changes that seem to take place in patients who are depressed.

BLUMENTHAL: "There's some data to suggest that patients with depression may have greater clotting of the blood. They may have lower heart rate variability, which is an indicator of autonomic nervous system dysfunction. They also may show dis-regulation of their blood vessels, blood vessels may not respond normally to various stimuli."

HOBAN: Blumenthal says this research underscores the need for doctors to assess their cardiac patients for depression and to aggressively treat it when they do find it. The study appears in the Archives of Internal Medicine. I'm Rose Hoban.

Finally today, a United Nations program that seeks to combat hunger by bringing agriculture to some of the world's most densely-packed cities.

The UN's Food and Agriculture Organization doesn't envisage tearing down buildings to create large tracts of farmland. Instead, the FAO is thinking along the lines of small vegetable patches, and even micro-gardens.

Takawira Mubvami of the Municipal Development Programme for Eastern and Southern Africa in Harare, Zimbabwe, says urban agriculture plays a critical role in nutrition.

MUBVAMI: "In southern Africa, in some of the contries, fresh food is very expensive. And urban agriculture affords the poor families the opportunity to actually have that fresh food at very minimal costs. And we have seen that leafy vegetables and other crops, which they grow, are primarily, first and foremost, for [their] own consumption. For the urban poor, urban agriculture is a vehicle towards food security and nutrition."

Elsewhere, the focus might be more on producing cash crops, says Prof. Ahlam El-Naggar of the Egyptian Ministry of Agriculture.

EL-NAGGAR: "Our concern in Egypt is to make the producers in urban areas share in the national economyby including them in the exportation system — cut flowers, plants which are very good for medicines, and all the exportation products or crops which doesn't need a large area of land."

Eric Kueneman of the UN's Food and Agriculture Organization admits that not every urban family will be able to grow enough food to meet all their nutrition needs year-round.

KUENEMAN: "But I don't think there's any question that families can raise and produce a lot of their own produce, even on window sills or, let's say, small terraces and so on. There are ways of micro-gardening that you can get surprisingly high amounts of good quality product from these systems. And in many cases they can produce enough, at certain times of the season, that they can't eat it all, and they can sell and get income from it."

Growing crops or raising livestock in or around the world's cities isn't going to end hunger, experts say, but with urban dwellers now outnumbering those who live in the country, urban agriculture could make an important contribution to putting food on the table of some of the poorest residents of the world's cities.

MUSIC: "Our World" theme

That's our show for this week. We're always interested in your comments, or maybe you've got a science question. If you'd like to get in touch, email us at Or use the postal address -

Our World
Voice of America
Washington, DC 20237 USA.

Rob Sivak edited the program. Eva Nenicka is the technical director. 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.