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Our World—16 September 2006

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

MUSIC: "Our World" theme

"It is an object 750 million years after the Big Bang. This is the most distant, single, identified object a human being has ever discovered." Our cosmic beginnings and more. Hi! I'm Rosanne Skirble, sitting in for Art Chimes. Welcome to VOA's science and technology magazine, "Our World."

Straight ahead on "Our World": A financial boost for a green revolution in Africa ... the continuing growth of global aquaculture ... and a new glimpse of the universe in its infancy.

The Bill and Melinda Gates Foundation and the Rockefeller Foundation - two of America's largest philanthropic institutions -- announced this week a 150 million-dollar, 5-year initiative designed to revolutionize food production and reduce hunger and poverty for millions of people in Africa.

The foundations' so-called "Alliance for a Green Revolution" is modeled on the "Green Revolution" in agriculture first promoted by the Rockefeller Foundation in the 1950s and credited with transforming farming methods and production in much of the world.

Over the last fifty years, farmers in Asia, Latin America and the Middle East have been able to triple their food production, while prices for staples like wheat, rice and corn have dropped by 76 percent. The gains have spared the world any widespread famine.

But the Green Revolution never took hold in Africa. Joining us to discuss why, and what the Gates/Rockefeller charities hope to do about it, is Pedro Sanchez. The winner of the 2002 World Food Prize, Mr. Sanchez is a world-renowned soil scientist who directs the Tropical Agriculture Program and the Millennium Villages Project at Columbia University in New York. Pedro Sanchez, welcome to "Our World."

SANCHEZ: Thank you for having me.

SKIRBLE: I'd like to begin by asking you why a green revolution didn't take place in Africa.

SANCHEZ: I think that there is a technological reason and a policy reason. In African small farms, the soil is depleted of nutrients - nitrogen and phosphorus -- and there is very poor water management. And, those conditions did not happen in Asia and in Latin America. The soils there were okay in terms of nutrients. Fertilizers were heavily subsidized by the governments and the aid agencies like U-S-A-I-D, and most of these areas had good irrigation. The mistake the development community did in Africa for the last fifty years [was] to ignore this obvious problem and think that by only having improved varieties of wheat and corn and sorghum and all the other [staples] that would do the trick. But none of these varieties, none of these improved crops can grow in soils without enough nitrogen or phosphorus. That is a biophysical impossibility. We need nitrogen for proteins in plants and for muscles in our bodies when we eat those plants, and we need phosphorus for photosynthesis in plants and we need phosphorus for making bones in our bodies. That was ignored. So the impact of high yielding varieties during the last 40 years in Sub-Saharan Africa has only been about a 28 percent increase as opposed to something in the order of 70 to 90 percent in Asia, Latin America and the Middle East.

SKIRBLE: How does the Gates/Rockefeller initiative differ? How is it going to get the job done?

SANCHEZ: "The Gates [Rockefeller] initiative follows a change that was basically initiated by the United Nations Millennium Project Hunger Task Force and it called for a different African green revolution by U.N. Secretary General Kofi Annan in 2004. What we in the Millennium Project and what the secretary general said is that you [must] pay attention to soils and water as well as improved [crop] varieties, improved nutrition of the children, make markets work for the poor, and you have to do all this in an environmentally sound way."

SKIRBLE: "How does this initiative fit into other on-going food, agriculture and health initiatives."

SANCHEZ: "I think it fits beautifully, encouraging everybody to do things that would meet the U.N. Millennium goals, not only getting rid of hunger, but reversing the path of HIV-AIDS, malaria and tuberculosis and having access to essential medicines. It is very complementary to the health initiatives that Gates [and others] have done. And, it [recognizes] a paradox: What is the point of having people healthy and free of malaria if they are going to die of malnutrition? You obviously need increased food production, increased nutrition and [better] health and they go together and the synergy is beautiful."

SKIRBLE: "How do non-profit organizations go about doing their business sidestepping what might be considered political corruption. In other words, how do you get the tools into the hands of the farmers that need them?"

SANCHEZ: "Okay, first, there are no cash transfers. You transfer things like bags of fertilizers and hybrid seeds. Those are a lot more difficult to run around and sell to somebody else. That is one very clear way of doing it. You deal with the actors - whether they are the farmers, the agro-dealers or the financial institutions directly and not through the governments. Unfortunately, there is more of a chance of corruption if it goes through the governments."

SKIRBLE: "Finally, what are your expectations [for the Gates/Rockefeller initiative] and is $150 million dollars enough?"

SANCHEZ: "No, no, it is certainly not enough, but it is a great step. It is a tremendous step. Other organizations such as 'Millennium Promise' have raised 130 million dollars in the last six months for the same purposes. So, things are beginning to happen. I think the prestige of Rockefeller … Rockefeller has done it before. It can do it again. The prestige of [Bill and Melina] Gates [Foundation] as the largest philanthropic institution in the world … Now they are getting into agriculture. God bless them! That is a tremendous step forward and I think that we are all thrilled."

SKIRBLE: "Thank you for your time."

SANCHEZ: My pleasure.

SKIRBLE: "Pedro Sanchez is the 2002 World Food Prize laureate, and director of the Tropical Agriculture Program and the Millennium Villages Project at Columbia University in New York."

From agriculture we turn to aquaculture, the fastest growing food sector in the world. According to a new report by the United Nations Food and Agriculture Organization, global fish farm production is increasing by 8 percent a year. However, rising consumer demand and declining catches of ocean fish are challenging the aquaculture industry to step up and bridge the gap.

The numbers tell the story: The aquaculture industry provides 43 percent or nearly half of fish consumed worldwide. That's up from just 9 percent in 1980.

"The State of the World Aquaculture: 2006" was released at an FAO meeting in New Delhi earlier in September. Rohana Subahsinghe heads FAO's aquaculture division and was lead author of the report. He says the real strength of the worldwide fish market is its diversity.

SUBAHSINGHE: "If you are talking about commercially- produced and internationally-traded commodities, I think that there is a tremendous demand for species like shrimp and salmon and catfish, which are being increasingly produced and also with a lot of screening for their production practices. The other fish which are low value and high quantity production fish like tilapias and carps, they are also increasing in production, but nevertheless prices are going down."

More than half the 600 fish species FAO monitors are listed as "fully exploited." Another 25 percent are described as either "over-exploited" or "depleted." Despite these statistics, Subahsinghe is optimistic that aquaculture can help bridge the supply gap as the wild fish catch declines. But he says producers will have to deal with rising energy costs, a shortage of investment capital and other obstacles:

SUBAHSINGHE: "One of the key challenges that aquaculture product producers will face is to produce a product that is environmentally friendly, socially acceptable and equitable and also, in terms of human health, a very safe product to eat."

At the FAO's New Delhi meeting, delegates from fifty nations took a major step toward those health and safety goals. They agreed on principles for sustainable shrimp farming - an industry that is often criticized for its adverse impact on the environment.

SUBAHSINGHE: "We are committed to assist the governments to improve the sustainability of shrimp farming. We are committed to providing support so that shrimp aquaculture sector will improve and also will be more environmentally sustainable. We've also been asked to expand our international principles development to other commodities like salmon, catfish, the mollusks and oysters. We will be working on that also."

According to the FAO, Africa is the only region of the world where fish consumption has declined over the past decade. Governments represented in New Delhi made a commitment to reverse that trend.

SUBAHSINGHE: "All governments, all developed and developing nations in that meeting unanimously agreed that we should provide more support and focus on Africa and aquaculture development as a part of Africa's development over the next decade."

Subahsinghe says aquaculture is critically important in the fight against global hunger. He says the new FAO report, "The State of the World's Aquaculture: 2006," provides an encouraging snapshot of an industry whose growth will provide food and jobs for millions in need.

We turn now to outer space where this week American astronauts began work again on the International Space Station for the first time since the Columbia Space Shuttle re-entry accident in 2003. Astronauts succeeded in deploying a 73-meter long solar array that will eventually power the station.

In other space news, as VOA science correspondent David McAlary tells us, astronomers have discovered some of the most distant -- and oldest -- galaxies ever seen.

Two studies in the journal "Nature" suggest that galaxies were forming when the universe was only six percent of its present age. That would be not long after the so-called Big Bang, the cataclysmic explosion nearly 14 billion years ago thought to have created all matter from an ultra dense mass the size of a pinhead.

In one paper, Japanese astronomers led by Masanori Iye of the National Astronomical Observatory in Tokyo report discovering the farthest galaxy yet seen.

IYE: "It is an object 750 million years after the Big Bang. This is the most distant, single, identified object a human being has ever discovered."

Iye's team used the Subaru telescope in Hawaii. They confirmed the age and distance of the galaxy by its redness. The redder an object is, the farther away it is. This is because light from receding bodies shifts downward into these lower light frequencies, just as the sound of a passing car horn drops in pitch.

Iye told Nature magazine interviewers that few galaxies existed at that primordial time.

IYE: "To our surprise, the actual number of distant galaxies at 750 million years after the Big Bang was only one third to one sixth of what we had expected. This decrease could be due to the evolution of the galaxy itself, so we have to study more carefully, looking into different directions of the universe, and looking also deeper into fainter population of galaxies."

Another group of astronomers using the Hubble Space Telescope also found galaxies a rarity in the infant universe. They looked slightly earlier, at about 700 million years after the Big Bang

BOUWENS: "What we've found is that at the very earliest epochs of the universe, there seems to be a very significant deficit of luminous galaxies."

This is Richard Bouwens of the University of California at Santa Cruz, also speaking with Nature magazine.

BOUWENS: "The universe is simply not old enough to have allowed these luminous massive galaxies to have formed."

When Bouwens' team peered at galaxies from a later period, when the cosmos was about 900 million years old, they found many more -- hundreds of them. The results of both studies support the idea that galaxies built up from much smaller pieces when the universe was between 700 million and 900 million years old.

BOUWENS: "The universe wouldn't necessarily look that much different than it does today, except that the galaxies that existed would be in much smaller pieces. In the universe that we see today there are lots of very big ones, but way back then, the galaxies would be very much smaller."

It is as if the baby universe experienced a growth spurt after 700 million years.

Our World's Website of the Week takes us on a trajectory that, like the new galaxies, is simply out of this world. In our flight around the Internet, we land today at cyber home of the Spitzer Space Telescope. Launched in 2003, the telescope is the final phase of NASA's Great Observatories Program, an initiative dedicated to observing the universe in four different kinds of light.

Spitzer's virtual home explores the magic and mystery of the universe -- in infrared.

Spitzer education and outreach director Michelle Thaller says infrared is invisible light, which can be detected as heat, or thermal radiation.

THALLER: "When you go to our website you are going to see these beautiful pictures of galaxies and stars and gorgeous big clouds in space, but what you have to keep remembering is that that is not visible light that you are looking at. Your eye would never see that image. That's an image that we have actually translated into wavelengths that you can see. It is a heat image that was invisible and we use false color to actually show you what is out there."

Thaller says infrared technology offers a chance to explore our cosmic roots and to observe how galaxies, stars and planets are born and develop.

THALLER: "We've taken pictures of stars that are just forming, baby stars that are still inside big clouds of dust that were invisible to us before, but we can actually see their heat coming out of the dust cloud. Amazing stuff! And we are also seeing all the way to the most distant galaxies in the universe. Some of the galaxies we are actually seeing in the infrared are so distant that you wouldn't even be able to detect them in visible light. They are too faint and too far away. Some of them are literally almost 13 billion light years away."

"Cool Cosmos" is a favorite page on the website. It's here, Thaller says, that teachers, museum-goers and students get a feel for what infrared light is all about. The concept is explained online with a trip to a more terrestrial setting: the Zoo!

THALLER: "We took pictures of reptiles which are cold-blooded. So they appear much cooler than a warm person holding them. We took pictures of sea lions, which are warm-blooded animals, but they keep their heat in so well that you can barely see them with a heat-seeking camera."

Another popular destination at is "Ask an Astronomer." Thaller says scientists from California Institute of Technology appear in video clips to provide answers to frequently asked questions.

THALLER: "They are wonderful… three-minute chunks that a teacher could even use in a lesson, for example. We tell people about 'why doesn't the moon fall down towards the earth,' or 'what exactly is a star, why does it live and die?' Our latest one is actually on black holes, and I know everybody loves black holes."

Thaller says while the Spitzer Space Telescope is expected to be retired by 2008, there is no end in sight for its cyber portal at

Finally today, the week in health: Older dads produce more autistic offspring; a compound in crab shell wards off bacterial infection; and a biodegradable napkin quickly detects biohazards.

Children of men over 40 have a significantly higher risk of autism than those fathered by younger men, according to a study in the September issue of the journal Archives of General Psychiatry.

Lead author Abraham Reichenberg of Mt. Sinai School of Medicine, New York and Institute of Psychiatry, King's College, London evaluated the age-related association in Israeli children born in the 1980s.

REICHENBERG: "The offspring of fathers who were forty years or older were almost six times more likely to have autism than the offspring of fathers who were younger than thirty years of age."

SKIRBLE: "How do you know that it is age related and not something different like genes or environment or something else?"

REICHENBERG: "We're not sure. We don't know yet. But the older age of the father was [also] associated with other neurological and psychiatric conditions, and there are effects of older fathers on the gene pool. So with age there is a higher likelihood for errors to accumulate in the male sperm, and that might be transferred to the offspring."

Reichenberg says better understanding of that genetic transfer could provide a clue about how brain disorders like autism develop and which genes are linked to the condition.

REICHENBERG: "The paternal age might target specific genes. It might suggest looking for mutations. Or [it might suggest] that there are other processes that might be flawed with older age. We know a little bit about [those processes] in genetics and we might start looking if those specific processes are also linked to autism."

According to the study, the mother's age was not a factor associated with autism. Reichenberg says the research adds to recent observations that men - like women - have 'biological clocks' for producing healthy babies.

Laboratory studies at Montana State University find that a chemical compound found in crab and shrimp shells known as chitosan can help prevent infectious bacteria from sticking to wound dressings, catheters and other medical devices.

Philip Stewart directs the University's Center for Biofilm Engineering. He says chitosan can stop nasty microbes on contact.

STEWART: It makes it hard for a cell to do anything active, and probably discourages the bacteria from setting up shop on that surface."

Once these layers of bacteria, or biofilms, 'set up shop' and take hold, they are difficult to treat and often require removing the device or surgical implant. Biofilms account for up to 65 percent of the bacterial infections in the United States, according to the Centers for Disease Control and Prevention.

Stewart says laboratory tests of bacteria growth showed dramatic results when chitosan was used.

STEWART: "When we do this on a surface that doesn't have chitosan we get about a million bacteria per square centimeter on that coating after two days of challenge. When we put the chitosan coating on and put it into the system and let it run for two days, we end up with around 10,000 times less bacteria on that surface."

Stewart says scientists were unable to detect any viable organism in five of the nine experiments using chitosan. He says that despite such results, it is unlikely that any single technology could defeat biofilms. But he suggests that chitosan is a likely platform from which to launch further experimentation.

STEWART: "We can load a conventional antibiotic [to the chitosan], or one of these agents that block the communication between bacteria that seem to be important in virulence and biofilm formation. So I think that combined strategies may be what really ends up working in the clinic."

Stewart presented his work in San Francisco at the 232nd national meeting of the American Chemical Society, the world's largest scientific society.

Cornell University scientists have designed a biodegradable absorbent wipe - much like a paper towel - that someday may be used to detect bacteria, viruses and other dangerous substances.

Speaking at the American Chemical Society meeting in San Francisco this week, Cornell assistant professor Margaret Frey told reporters that tiny sensors embedded in the material signal the presence of pathogens.

FREY: "You would swab the area and then add a few drops of another liquid [to the material] or drop it into a little tube of another liquid and get a color change."

Once fully developed, the wipe would contain nanofibers implanted with antibodies that would identify numerous biohazards and chemicals. Frey says Cornell scientists have thus far only tested it on E-coli bacteria.

FREY: "I think that what is mainly holding us going past one is just resources."

Frey says researchers are currently seeking partners to expand the technology. She predicts it could have widespread appeal especially since it could be produced cheaply and wouldn't require training to use. Fray says applications could extend from meat packing plants and hospitals to airplanes and cruise ships.

THEME music

And, that's our program for this week. Rob Sivak is our editor. Our technical director is Eva Nenicka. I'm Rosanne Skirble. Join us online at or on your radio next week with Art Chimes at this same time as we explore the latest in science and technology on "Our World."