Accessibility links

Our World — 23 June 2007

MUSIC: "Our World" theme

Straight ahead on "Our World" ... A new campaign against drug-resistant tuberculosis ... the songs of insects ... and going inside your head to see why doing good feels good.

GRAFMAN: So we thought, 'Let's focus on this particular kind of behavior because these other species tend not to be particularly altruistic, whereas humans tend to do this a lot.'"

Those stories, this year's winner of the World Food Prize, and more. I'm Art Chimes. Welcome to VOA's science and technology magazine, "Our World."

The World Health Organization and the Stop TB Partnership Thursday launched a $2 billion campaign to fight drug-resistant tuberculosis and save as many as 134,000 lives a year.

The WHO says there are an estimated nine million new cases of tuberculosis each year. Most cases can be treated with established drugs, but about one in twenty doesn't respond to the usual treatment. The head of the WHO's Stop TB Department, Mario Raviglione, says those patients then require so-called second-line drugs that are more more expensive and harder to use.

RAVIGLIONE: "If then, a patient at a certain point develops a form of TB that is not just multi-drug resistant, i.e. resistant to the basic treatment, but also now resistant to additional, second-line drugs, you are facing what is called XDR-TB or extensively drug-resistant TB."

The drug resistant varieties of tuberculosis have emerged in part because patients sometimes don't follow through with their treatment, which continues long after symptoms have disappeared. That gives TB bacteria a chance to regroup and develop resistance. That's one reason why treatment of TB patients needs to be managed carefully, says the WHO's Paul Nunn.

NUNN: "Drug resistance occurs when basic TB control is not sufficiently invested in, when the use of drugs is not properly done, when there is poor management of those drugs. And, also when the conditions are right for the transmission of TB, including drug-resistant TB around health facilities, around airplanes, buses, whatever."

Tuberculosis is particularly dangerous for patients who have a compromised immune system, notably people with HIV/AIDS.

The World Health Organization wants all patients with drug-resistant tuberculosis to have access to treatment by 2015.

Determining the right dosage for a vaccine can be tricky. You want to get enough vaccine to stimulate the production of antibodies against the disease, but too much would be wasteful and possibly harmful.

The issue could be critical in the case of a sudden outbreak of disease, when there is a surge of demand. That could be the scenario if the deadly H5N1 strain of avian flu mutates to allow the bug to be easily spread from person to person. So scientists are trying to assess the effectiveness of a smaller dose of vaccine — which would allow the available amount of vaccine to be used to protect more people.

Our story, based on a study published in the journal PLoS Medicine, was written by Adriana Salerno and is read by Veronique LaCapra.

LaCAPRA: Countries around the world are preparing for a global outbreak of avian flu. Although the H5N1 influenza virus is always mutating, Steven Riley, from the University of Hong Kong, says researchers are developing and stockpiling vaccines anyway.

RILEY: "So this is a human vaccine, which is formulated and targeted against the current avian strain. The rationale is that there will be a very small mutation within the strain that will allow it to cause human disease and to cause human infection and that if you formulate the vaccine against the current strain they'll be available and ready to go when we have a human pandemic."

LaCAPRA: Even with this effort, scientists think there may not be enough vaccine for everyone, so a natural question arises: who gets vaccinated? The standard procedure is for certain high-risk groups to get the vaccine first: healthcare workers, emergency personnel, children and the elderly. Riley and his colleagues propose a radically different approach: use lower doses and vaccinate more people.

RILEY: "And our findings are there are likely to be substantial reductions in the proportion of people who are likely to be infected if you give a lower dose to more people than if you give the maximum tested dose to fewer people. Our estimate is that if 160 out of the 300 million people in the US were given the lower dose rather than 20 out of the 300 million given the maximum protected dose, you could be talking about 27 million fewer infections."

LaCAPRA: Riley arrived at these estimates by using a simple mathematical model. The results seem promising on paper, but he acknowledges that much depends on understanding the nature of protection:

RILEY: "So when people do have partial protection from vaccination against influenza, what does that mean? Does that mean that some people will have no chance of being infected despite many challenges? Or does it mean that they might just be protected for a couple of challenges and then get infected later in the epidemic? I think there's some basic science issues that we need to resolve as well."

LaCAPRA: As researchers continue to develop vaccines, Riley hopes his study will give policy makers another, possibly more effective, option for protecting the public from a pandemic.

The World Food Prize — an award established 20 years ago to honor people who've helped improve the world's food supply — this year will be awarded to Philip Nelson, a professor at Purdue University in the U.S. state of Indiana. The prize recognizes Nelson's pioneering work on technology that allows food to be stored and transported without refrigeration.

The announcement was made Monday here in Washington by World Food Prize Foundation president Kenneth Quinn. He noted that many American food processors use the aseptic techniques - which we'll explain in a moment - to bring food from farm to table.

QUINN: "But perhaps most significantly, our laureate's technology permits food to be stored and transported within developing countries - there's a special project within Senegal to do that - and also allows relief agencies to deliver significant quantities of food and water to remote or cut-off areas during times of great crisis, such as the tsunami that devastated parts of Indonesia or hurricane Katrina that hit the US gulf coast."

Most often, though, aseptic bulk processing and shipping allows the safe and economical movement of many foods from farm to processor without the need for refrigeration. Philip Nelson describes the aseptic process as much like canning, except that the rapid heating and cooling of the food product takes place outside the container.

NELSON: "We can actually heat it up very quickly and cool it down quickly. Therefore we don't lose nutrients and flavor. We sterilize the food outside of the container; we sterilize the container separately; and then, in a sterile environment, we bring the two together."

Not all foods can be processed this way. There are a lot of tubes and pumping involved, so liquids like fruit juices are ideal. Tomatoes, most of which end up in juices, sauces and other processed forms, are also ripe for aseptic processing. According to the World Food Prize Foundation, of almost 22 million [metric] tons of tomatoes harvested each year, 90 percent are processed aseptically.

NELSON: "Probably the next biggest would be orange juice. We have banana puree. We've got a number of the exotic fruit purees that we use in fruit drinks. Grape, apple, apple products, pumpkin. A lot of different products."

Around the world, fruits and vegetables are processed aseptically and shipped in various kinds of aseptic containers. Think of them as the grown up version of the familiar one-liter box of milk you may have at home. Industry standard aseptic containers are flexible bags holding 1,100 liters. There are even ocean-going ships with giant aseptic storage tanks carrying as much as 28 million liters of orange juice from Brazil to North America. The sterilized food inside stays fresh for weeks, months or longer without refrigeration.

The choice of Philip Nelson as the winner of this year's World Food Prize was welcomed by others in the food technology field, including John Rushing, professor of food science at North Carolina State University.

RUSHING: "Dr. Nelson is certainly a good choice for the World Food Prize. He is a top food technologist. He's been a leader in the field, and he's been very innovative over the years. We've had a real terrible problem moving product from one country to the other without a loss of product or without damage to the product. Aseptic processing allows us to do that."

The World Food Prize, which is worth a quarter million doillars, will be presented to Dr. Philip Nelson of Purdue University in October.

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

This week, the world's largest academic library meets the Internet as we explore the digital collections of the Harvard University Library.

VERBA: "It's a program in which we try to take materials that are at the Harvard library that ordinarily would be just locked into the library - people would have to come and use them here - and by using digitization make it available all over the world for free.

Sidney Verba is the director of the Harvard University library, home of the Open Collections Program at

For its online collections, Dr. Verba's team is working thematically, drawing resources from throughout the vast resources of the Harvard Library system. One collection that you might find interesting is called Women Working, about the role of women in the American economy.

VERBA: "It is a collection of 3,500 books, more or less, thousands of pages of manuscripts, photographs and the like. And it forms background material for people teaching courses in economic history, in women's history and subjects of that sort."

Those 3,500 books, we should stress, are posted online in full — scanned images of every page. Other collections focus on biological diversity in China and Tibet, 19th century American advertising trade cards, and the history of immigration to the United States from the late 1700s up to 1930.

VERBA: "We scan materials about the anti-immigration league in the United States, about immigration support groups. We scan lots of photographs. And it really gives one a sense of what real history was like."

A serious online research tool or just fascinating browsing, courtesy of, or get the link from our site,

MUSIC - Modest Mussorgsky: "Pictures at an Exhibition" (Chicago Symphony Orch., cond. by Fritz Reiner, 1957)

The pictures are better on VOA's science and technology magazine, Our World. I'm Art Chimes in Washington.

Time to get inside your head now with a field of medical research known as cognitive neuroscience. It examines the role of the brain in the way we interact with the people around us. As VOA's Andrew Baroch reports, a new study of the parts of the brain involved in making ethical choices suggests that human altruism may have a biochemical basis:

BAROCH: Dr Jordan Grafman is the chief of the cognitive neuroscience section at the National Institutes of Health in Bethesda, Maryland.

GRAFMAN: "The field I work in is called 'cognitive neuroscience.' It's a merging of two areas of study: cognition, which is trying to better understand how we think about things, how we reason or plan; and neuroscience, which is very much concerned about brain mechanisms of behavior. And when you put the two together, you're really trying to identify which brain regions and processes are active when you're doing a specific cognitive task. So it's called 'cognitive neuroscience.'"

BAROCH: Grafman is particularly interested in the connection between human behavior and the so-called frontal lobes of the brain.

GRAFMAN: "You put your hand on your forehead above your eyes, and you go back to about the middle of your ears. And over the top of your head, that's your frontal lobes."

BAROCH: Dr. Grafman recently studied images of volunteers' frontal lobes, examining in particular what the area looks like when the volunteers chose to care about others - in the test case, to donate money to a good cause - or when they chose to act indifferently.

GRAFMAN: "We asked normal volunteers to sit in an MRI scanner and look at people's willingness or unwillingness to donate money to non-profit organizations. And we suspected, initially, that this would involve areas of the brain that we know are important for human behavior in particular, as opposed to, for example, monkeys or orangutans, great apes. So we thought, 'Let's focus on this particular kind of behavior because these other species tend not to be particularly altruistic, whereas humans tend to do this a lot.'"

BAROCH: The major finding, says Dr. Grafman, is that people felt good - their brains felt pleasure - when they acted altruistically. The pleasure was more intense giving money than receiving.

GRAFMAN: "What we found was the same areas of the brain that tend to get active when you reward somebody — that is, you give them money, you give them food, you appeal to some hedonistic way — well, those same brain structures were activated in the donation condition. And that surprised us. And more so surprised us because there was more activation in the donation condition than the reward condition."

BAROCH: Some neuroscientists have said the study suggests that ethics and morality are beyond human choice, that the basis of altruism is in the brain's pleasure centers, and that people who lack the brain chemicals that induce altruism may perhaps not be held responsible if they do selfish or negative things.

Joshua Wine is a scientist and philosopher at Harvard University. He says that's taking the study's findings too far.

WINE: "It's a mistake to say, we just saw it in the brain, therefore it's biology; therefore it's not learned, and it's hardwired. I mean, that's just a mistake. It may be true that people are altruistic and that altruism is rewarding, but that doesn't mean we have a hardwired biological drive. There's something in the brain that makes us do everything that we do. Otherwise we wouldn't do it."

BAROCH: Dr. Grafman agrees.

GRAFMAN: "I think brain research just teaches us a little bit about how the brain interacts with our behaviors. And learning about how that works can inform us about the biological basis of some of our behaviors, but it doesn't tell us which behaviors are appropriate or not. That's our judgment, our conscious and explicit judgment as people."

BAROCH: Other researchers contend, however, that down the road insights gained from studies in cognitive neuroscience may lead to new assessments of people who engage in unethical, immoral, or criminal behavior. I'm Andrew Baroch.

Finally today, you may enjoy listening to the sounds of birds. Even if you're not knowledgeable enough to identify birds by their sounds, bird songs can be pleasant, relaxing, even entertaining. Now, a new book and a companion CD aim to stimulate interest in another form of wildlife, as VOA's Susan Logue reports.


LOGUE: That's a common sound in many American backyards on warm summer evenings: the song of Allonemobius allardi, or Allard's ground cricket. It's one of 75 insect species recorded and photographed for "The Songs of Insects."

Wil Hershberger says he and co-author Lang Elliott had both been interested in recording the sounds of nature before they got together to work on this project.

HERSHBERGER: "We both were very interested in the vocalizations of birds and frogs and toads. That's a spring event, and by the time summer rolls around, the birds are silent, the frogs are silent, but there are all of these insects singing."

LOGUE: They both started recording insects individually and eventually joined forces. The result is a colorful book with pictures of each insect, accompanied by a map of its territory, tips on identification, and sonograms and descriptions of songs. "The Songs of Insects" includes an audio CD with a recording of each species singing. This is the black-legged meadow katydid:

AUDIO: Black-legged Meadow Katydid

HERSHBERGER: "We would go out in the field with short shotgun microphones and digital recorders and try to get as close to the singer as possible without disturbing it. As soon as you disturb it they either jump or fly away and stop singing for long periods of time."

LOGUE: Hershberger says many insects, like bees, flies and mosquitoes, make sounds, but only a few actually sing.

HERSHBERGER: "If you define song as some kind of auditory communication to attract a mate or defend a territory, all of the insects in this book are singers.


LOGUE: Cicadas are the loudest singing insects in North America. "The Songs of Insects" features 13 species. This one is Linnaeus's 17-year Cicada, which has recently made an appearance in parts of the Midwestern U.S.

The author says 80 percent of the 75 different insects featured in the book are identifiable by their songs. The other 20 percent have songs that are very similar.

Only male insects sing and they don't sing like humans or birds. They don't have vocal chords. Crickets and katydids use their wings, as Wil Hersherberger explains.

HERSHBERGER: "On the bottom side of one wing is this line of teeth that looks like a file when you magnify it. And on the upper side of the other wing is a hard ridge that is called a scraper. As the male opens his wings, he lets the teeth pass over the top of that scraper, but when he closes, he drags the scraper across the teeth of the file. And it sets little membranes in the wings into motion, which creates sound."

LOGUE: Technically, they don't sing, they stridulate. Some grasshoppers and locusts drag their back legs over the edge of their wings to stridulate. Others don't stridulate at all; they crepitate, popping their wings taut to create this sound:


LOGUE: Wil Hershberger says cicadas don't use their wings at all to sing. They use a tymbal.

HERSHBERGER: "It's a taut membrane that has several ribs to support it underneath, and attached to the ribs is this really strong muscle. Contracting and relaxing that muscle very rapidly creates that popping sound. There is a hollow area under the tymbal that helps to amplify the song.


LOGUE: Wil Hershberger hopes "The Songs of Insects" will generate a new appreciation for the six-legged creatures and the unique music they create. I'm Susan Logue.


MUSIC: "Our World" theme

That's our show for this week. We're always interested in your comments or your science questions. 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 technology ... in Our World.