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Our World — 13 September 2008

MUSIC: "Our World" theme

This week on "Our World" ... One country's approach to delivering quality and value in health care ... higher food prices and a hungry world ... and changes in the oceans that could threaten coastal ecosystems ...

HOLZER: "Recently there's been evidence that ocean acidification is happening. And that can be very harmful to biological life of all different types."

Those stories, a conversation with a prize-winning biochemist, and more. I'm Art Chimes. Welcome to VOA's science and technology magazine, "Our World."

New findings about Africa's climate

Researchers say they have the first evidence that climate in Africa is influenced by conditions in the northern hemisphere, a finding that contradicts the main theory about climate in the subtropics. As VOA's Jessica Berman reports, scientists say the discovery, which was announced on Thursday, will help them make future climate predictions.

BERMAN: Climatologists have long debated what forces make countries in the tropics hot and humid and those in the northern hemisphere relatively warm and mild.

Andy Cohen is a professor of geosciences at the University of Arizona in Tucson.

COHEN: "The tropics are the heat engine of our planet, if you will. And so it's really important for understanding climate history, and it also gives us a background for understanding and evaluating the kinds of climate changes that we're seeing around the world today."

BERMAN: In a study published this week in Science, researchers offer the first solid evidence that the climate in tropical Africa is influenced by conditions in the northern latitudes, not by solar radiation patterns along the equator as is generally believed.

Investigators base their conclusion on an analysis of a 60,000-year-old sediment core extracted from the bottom of Lake Tanganyika in the East African Rift Valley, which borders Burundi, Democratic Republic of the Congo, Tanzania, and Zambia.

Researchers found evidence in the long core sample, including leaf wax, which traces Africa's climate to the northern hemisphere.

Jessica Tierney is with the department of geological sciences at Brown University in Rhode Island and lead author of the study.

Tierney says there are indications within the core sample that climate conditions in Africa alternated dramatically over tens of thousands of years.

TIERNEY: "In the past we see these very abrupt changes from conditions that are arid to conditions that are quite wet. And these changes can happen within several hundreds of years. That's very fast on the geologic scheme of things."

BERMAN: In modern times, Tierney says it appears most of the influence on Africa's climate comes from forces in and around the Indian Ocean.

TIERNEY: "Most of the rain that falls over Lake Tanganyika today, that water that came from the Indian Ocean, it was evaporated in the western Indian Ocean and transported by winds to the lake."

BERMAN: Experts say the study, which involves ancient climate records, does not address the impact of global warming.

But the records could offer a template against which to measure global warming, according to Andy Cohen, a study co-author.

COHEN: "It allows us then to say how big are the changes that are occurring now in comparison to those natural changes that occurred before people were pumping carbon dioxide into the atmosphere."

BERMAN: Researchers are conducting similar long core studies of Lake Malawi in the Rift Valley to confirm their findings. Jessica Berman, VOA News, Washington, DC.

Malaria researcher Joseph DeRisi wins Heinz Award

A University of California scientist who invented a way of rapidly identifying viruses that cause disease has been awarded the prestigious Heinz Award for Technology.

Biochemistry professor Joseph DeRisi was this week named winner of the prize.

At his lab in San Francisco, researchers are exploring new ways to attack malaria.

Earlier, DeRisi and his colleagues developed the ViroChip, a small glass slide with a microarray of 22,000 sequences of DNA - the molecular chains of amino acids that carry an organism's hereditary code. It helped DeRisi identify the virus that causes SARS, among other microbes.

As the Heinz Foundation noted, he did not patent the ViroChip, so the technology is now in the public domain - free for other scientists to use.

He was also the recipient, four years ago, of a MacArthur fellowship, the so-called "genius grant."

I reached Dr. DeRisi by phone shortly after the award was announced.

Q: Well first, congratulations on winning the Heinz award. How did you find out?

DeRISI: I received a call from Teresa Heinz, and I was absolutely surprised and thrilled.

Q: What got you interested in your field to begin with?

DeRISI: Well, I did my PhD in biochemistry at Stanford University, and there I worked on model organisms like yeast. And you can learn a lot by studying a model organism. When I came to University of California-San Francisco, I really wanted to turn my attention to something that might have direct impact on human health or veterinary health, or basically anything that I could do to turn technology that I had developed into something directly applicable.

Q: One of the things that you've been working a lot on is malaria. Why is that important to you

DeRISI: When I came to University of California-San Francisco to work on infectious disease, I looked around to different options, and malaria was particularly interesting and fascinating to me. It's amazing that after 100 years of study of this little parasite, we've not been able to effectively control it. So I thought that I could bring new technology and new approaches to the study of this parasite in a way that might be able to help us, either create a new therapeutic or prevention strategy.

Q: So what's the approach that you lab has been taking?

DeRISI: First of all, we're trying to develop new drugs that work against malaria, because frankly that's where all the success against malaria has been over the last 400 years or so. The other area is to understand more about the parasite, how it interacts with our immune system, and how it actually goes about its business of creating infection. We're also trying to think up novel, interesting, nonconventional or radical approaches to malaria as well.

Q: One of the things you're perhaps best known for is the ViroChip. Can you explain what that is and how it's used?

DeRISI: Sure. The ViroChip is a DNA microarray. That is, a very small, solid substrate — a piece of glass, a microscope slide — that contains thousands of pieces of different DNA, representing all viruses that we know about today. As you may know, many human diseases, even some cancers, are associated with viruses. And so, surveying the way viruses that have been discovered in the past, I came to the conclusion that I could use my technology that I developed as a graduate student — DNA microarray technology — to create a chip that would simultaneously screen for all viruses ever discovered, and furthermore have the built-in capability of discovering new viruses. And with this chip we can take essentially any human sample, put it on the chip, figure out what viruses are in there. It's a very quick, easy assay.

Q: I was looking at your lab's website and the first thing I see is a couple of bird pictures, which I actually did not expect. How does bird disease fit into the work you're doing?

DeRISI: Well, the virus chip that we created is useful for almost any disease, whether it be a plant disease, a bird disease, a human disease or whatnot. And so, we were contacted some time ago by several veterinarians who said, you know there's a disease that's been killing exotic birds — parrots, cockatiels, cockatoos, so on — for a long time now, for 40 years. And we've been banging our heads against this disease and not been able to cure it. And why is it a problem? This disease, called PDD [Proventricular Dilatation Disease], has been affecting large aviaries, zoos, and conservation efforts across the world. And essentially they're powerless to stop this disease, which just makes the birds waste away until they die. And so, we took tissue samples from birds that had died of PDD, put them on the virus chip, and we were able to discover a brand new virus, which we believe is the cause of this disease.

Joseph DeRisi is this year's winner of the Heinz Award for Technology, which is worth a quarter-million dollars.

Indian hospitals seen as models of efficiency

Here in the U.S., we spend more per person on health care than any other country. We have lots of great hospitals and doctors, but many Americans think we could do a lot better, considering how much we're paying. So American academics are looking around the world for ideas about how to make health care more affordable. Health reporter Rose Hoban has more.

HOBAN: One of the biggest problems facing the U. S. health care system is money. Services cost a lot, and many people don't have the money or insurance to pay for the health care they need. So, American academics are looking around the world for ideas about how to make health care affordable. Some professors from Duke University in North Carolina think they've found some examples that work in India.

Kevin Schulman is a physician and a professor of business at Duke. He went to India to study their health care system. He says the health care market there is fiercely competitive, and a new class of hospitals has emerged in the past two decades to serve the rapidly expanding middle class.

SCHULMAN: "Most of the hospitals that we looked at had very, very high-volume, so their are surgeons are really very technically excellent."

HOBAN: Schulman says care provided in the Indian hospitals was of consistently high quality, and doctors were paid incentives to do good work.

SCHULMAN: "Where they need to make investments to make the operating rooms the best that they could be, they made the investment. But where they needed to make investments to make the rooms look a little nicer, they saved money in order to save the patient money.."

HOBAN: Few people in India have health insurance, and most medical care is paid for out of pocket. Schulman says that means patients need to know what they'll need to pay — this is unlike the U S system, where insurance companies negotiate prices directly with hospitals. This is also unlike the system in many European countries, where the government pays the bills. But Schulman says in India, patients are conscious of cost and of getting a good value.

SCHULMAN: "If the hospital tells you your service is going to be a certain amount, then complications that arise as a result of surgery in some cases are even eaten by the hospital, financially. So, there's a financial incentive for the hospitals to deliver high-quality service. There is moreover a custodial reason that they feel that when they make a contract with someone to offer a service, they're bound to deliver that service at that price."

HOBAN: Schulman also says Indian doctors and nurses are extremely proud of their health care system — and of how sophisticated it's become.

His paper is published in the journal Health Affairs. I'm Rose Hoban.

Medical information and health news on

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

This week, we're featuring one of the top medical information sites on the Web.

SMITH: "On WebMD, we have both medical news and general health information. We actually have a WebMD news center. In addition we have an expansive medical library with everything from videos and tools to features and a complete reference library."

Dr. Michael Smith is the Chief Medical Editor at, where you can keep up with the latest medical research, learn about specific diseases and conditions, and even try to diagnose a problem through the "symptom checker" feature. And everything is reviewed by experts.

SMITH: "So every piece of content on our site actually goes through a doctor's eyes. A board-certified physician will look at the content, make sure it's up to date, accurate, and doesn't have anything misleading that might be misconstrued by a lay audience."

Among the site's many other features are almost 200 message boards on subjects ranging from allergies to yoga.

SMITH: "The message boards allow you not only to communicate with others living with your condition, but it also allows you to post questions for health experts, either physicians or nurses, a wide variety of health professionals, even nutritionists in the diet and nutrition area, to actually post questions to them, ask a specific question, and get a response back."

There are also special sections for men, women, and children's health issues, nutritional advice, and much more.

Good health information is only a click away at, or get the link to this and more than 200 other Websites of the Week from our site,

MUSIC: Horace Silver — "Doctor Jazz"

Healthy listening on VOA's science and technology magazine, Our World. I'm Art Chimes in Washington.

Reducing hunger amidst rising food prices

At the annual National Food Policy Conference in Washington this week, some of the country's leading food and development experts gathered to discuss new strategies for reducing global hunger in a time of high food prices. Véronique LaCapra was there and has this report.

LaCAPRA: Worldwide, the demand for food is increasing.

LARSEN: "We have a world population that's growing by more than 70 million people each year."

LaCAPRA: Janet Larsen is the Director of Research at the Earth Policy Institute, an environmental research organization that focuses on sustainable development.

LARSEN: "Around the world there are four billion people trying to move up the food chain, consuming more grain-intensive livestock products. And then we have as we've heard a lot about today, the growing diversion of food to fuel, to run our growing automobile fleets."

LaCAPRA: And global food production has not been keeping pace with increased demand.

LARSEN: "In 7 of the last 8 years, the world has consumed more grain than we have produced."

LaCAPRA: Ann Tutwiler, the managing director for Trade and Development at the William and Flora Hewlett Foundation, says inadequate investment in agriculture is a major reason why today, food demand is outstripping supply:

TUTWILER: "Developing country governments and aid agencies around the world have been putting less money into agriculture. Spending on farming as a share of public spending fell by half between 1980 and 2004. While official development assistance has almost doubled in the last five years, the agricultural share of that official development assistance has fallen from about 20 to 15 percent."

LaCAPRA: With demand already exceeding production, the recent spike in food prices has been a disaster for the world's poor. David Beckmann, president of the hunger relief organization Bread for the World, says that the impact has been most severe in 35 low-income countries that depend heavily on imports for food.

BECKMANN: "Many of them are sub-Saharan African countries. Those 35 countries are spending $60 billion more on food imports this year, than they did in 2006."

LaCAPRA: The World Bank estimates that the surge in food prices could push a hundred million more people deeper into poverty.

And according to Janet Larsen, environmental problems will exacerbate the crisis.

LARSEN: "We're looking at a future of water shortages. About 70 percent of all the water that's used around the world goes to irrigate crops. Irrigation has tripled since 1950, but we've tripled our irrigation by over-pumping underground water resources, diverting rivers so that they no longer make it to the sea."

LaCAPRA: To address the food crisis in the short term, says David Beckmann, wealthy nations like the United States need to increase food aid funding.

BECKMANN: "But we also need to use those dollars better. When we appropriate money for food aid that can be purchased locally, we get about twice as much help for hungry people with every dollar."

LaCAPRA: Daniel Gustafson of the United Nation's Food and Agriculture Organization agrees:

GUSTAFSON: "We know from long experience that cash or additional income that is spent within let's say sort of the village economy, has a much larger impact and a much larger multiplier effect when that money circulates among what other people in that village economy are selling rather than what they're buying in from the outside."

LaCAPRA: Gustafson says that rural economies also benefit if agricultural inputs, like fertilizer and seeds, can be purchased on the local market.

In addition, says Gustafson, programs that provide cash to small farmers can help them break out of the cycle of poverty and hunger.

GUFSTAFSON: "A big issue for most — almost all smallholder farmers is this liquidity problem of not having cash at the right time. You can't get credit, you can't get it at the right time, you end up selling off your goats or your livestock and so on, and you end up actually through periodic crises getting worse and worse and worse. So if you have a little bit of extra cash you can not only make it over those difficult periods but you can in fact invest some of that in productive assets."

LaCAPRA: The experts stressed that to address the global food crisis in the long term, low-income countries will need more funding for agricultural development. For Our World, I'm Véronique LaCapra.

Ocean CO2 could endanger fragile coastal waters

Finally today: carbon dioxide, or CO2, is probably the best-known greenhouse gas. But CO2 isn't just something that causes global warming in the atmosphere. Half of all CO2 from human activity is stored in the world's oceans, where it increases the oceans' acidity. As Ann Dornfeld reports, that acidification is threatening fragile coastal areas.

DORNFELD: If you've ever wondered why sparkling water tastes tangy, instead of just bubbly, it's because of carbonic acid. That's what's produced when carbon dioxide is added to water. Some of the CO2 in the world's oceans is natural, from things like decaying algae. But the oceans also soak up CO2 produced by cars and factories. Once CO2 is absorbed into the ocean, it sinks to the coldest, deepest water for long-term storage.

Chemical oceanographers at Oregon State University are monitoring the chemical composition of the Pacific Ocean to see where the carbon is being stored. On a research vessel several miles off the coast, they lower a series of bottles down to the ocean floor on a winch.

Scientists have expected that upwellings would eventually bring some of that CO2 to the coastal zones that are home to a huge array of marine life. They thought it would take a century or more. But a recent study, published in the journal Science, found acidic water fewer than 32 km. off the Pacific Coast.

Grad student Rachel Holzer says that's alarming.

HOLZER: "The ocean is normally at a very stable pH. It is a buffered system, which means it is not very easy for the pH to change. But recently there's been evidence that ocean acidification is happening, meaning that the pH is dropping. And that can be very harmful to biological life of all different types."

DORNFELD: Corrosive water can dissolve the calcium carbonate shells of barnacles, mussels, oysters, and clams. Coral reefs are also calcium carbonate. So are a lot of planktonic species, including terrapods. Those make up about half of the diet of young salmon.

Burke Hales co-authored the latest study. He's an Associate Professor of Chemical Oceanography at Oregon State University.

HALES: "The question is how are these organisms going to respond, you know? Do their shells dissolve, do they just not grow as quickly? If their shells are negatively impacted, are the organisms themselves negatively impacted? And if the organisms are negatively impacted, how does that cascade through the food web?"

DORNFELD: Hales says stopping ocean acidification would be extremely difficult, if not impossible.

HALES: "There are people who have talked about going out in the ocean and spraying sodium carbonate pellets into the water, which would dissolve and neutralize some of the carbonic acid. That's one idea that's been proposed. It's really, really speculative that that would work."

DORNFELD: What's more, Hales says the process of hauling all of that ocean antacid out to sea and dispersing it could produce as much CO2 as it would neutralize.

HALES: "It is depressing. We wish things weren't this way and moving sort of irreversibly towards worse conditions. But we also know that the oceans do have a lot of ability to adapt. And what we don't know yet is exactly how this is gonna play out."

DORNFELD: One thing scientists do know is that the acidification has just begun. The corrosive water they found right off the Pacific Coast was from carbon dioxide released about 50 years ago. And over the last half century, CO2 production has only increased.

For the Environment Report, I'm Ann Dornfeld.

Support for the Environment Report comes from the Joyce Foundation, the George Gund Foundation, and the Americana Foundation. You can contact them at

MUSIC: "Our World" theme

That's our show for this week. 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 show. 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.