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Our World — 9 December 2006

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" ... Presentation this weekend of the Nobel Prizes; we talk with some of the winners ... water on Mars and men on the moon ... and how climate change is affecting agriculture ...

PARRY: "We are going to have to adapt. We cannot scrub that away. Even if we chop emissions off at the knees now we are not going to be able to mitigate our way out of the problem."

Those stories, videos for scientists, and more. I'm Art Chimes. Welcome to VOA's science and technology magazine, "Our World."

This is the weekend when the Nobel Prizes are presented — in Oslo, for the Peace Prize, and in Stockholm for the others. Five American scientists will be accepting awards for physics, chemistry, and physiology or medicine, and four of the five stopped by the Swedish embassy here in Washington to talk about their work and what it means

NASA scientist John Mather and his colleague George Smoot of the University of California are getting the physics prize for their work on probing the origins of the universe. As Smoot explains, they used measurements from the Cosmic Background Explorer, or COBE, satellite to create a map of the infant universe just after the Big Bang, which showed irregularities that would become the galaxies, stars and planets that later came into being.

SMOOT: "What we did was, we used this light from the very early universe to make a picture of what the early universe looked like. So when you look out at the sun, you don't actually touch the sun, you see an image of the sun — either photographic or in your eyes - that shows you what the sun looks like. And it's what the sun looked like eight minutes ago. We look much further out. So if you look at the nearest stars it's a few years ago, if you look at the nearest galaxies it's two million years ago. We looked back to almost the very beginning of the universe and made an image of what the universe looked like at a time when it was very, very young. It's sort of in the embryonic stage, that's later on going to develop into the universe we see today."

The prize in physiology or medicine went to Craig Mello and Andrew Fire for their work on RNA interference. RNA is the genetic stuff that takes the instructions in DNA and transfers the information to the proteins that actually do the work. RNA interference is basically a way of preventing the instructions in DNA from being carried out. For now, it's mainly helping researchers in the laboratory, but Andrew Fire of Stanford University says it holds out the prospect of treating diseases such as cancer:

FIRE: "There's an area, which a lot of us are very, very excited about, which is the area of therapeutic RNA interference. For instance, if we want to shut down a gene that's responsible for a tumor progressing, we can put in the double-stranded RNA for that gene, and we can ask for the tumor to then do something we want to do, which is, for instance, regress. And that kind of work has begun in a number of different settings. I think it's going to be something like a five, 10, 15 year process, rather than walking into the drugstore tomorrow and picking up a pill of double-stranded RNA."

Fire and Mello's RNA work would seem to be worlds apart from Smoot and Mather's on the origins of the universe. But the scientists find common ground in that all of them are, in very different ways, trying to answer the question of where we come from. Every culture, every tribe has a story of its origins. Sometimes it is steeped in mysticism and legend. For others it's based in astronomical observatories, archaeology and biology.

For the physics laureates, who probed the origins of our universe, the link is pretty apparent. Perhaps not as obvious, though, for the RNA researchers. But Craig Mello points out that while individual species may come and go, the fundamental mechanisms of life have been around for a very, very long time.

MELLO: "The thing that I find as a biologist to be one of the most incredible discoveries of modern biology is the remarkable stability of biological mechanisms over geological time, or you could even say over cosmological time, because it's that amazing, that creatures that shared a common ancestor more than a billion years ago still use the same basic genetic code to interpret sequences of their genes in order to make the proteins. I find that amazing."

Incidentally, if you sometimes find it a bit difficult to follow the groundbreaking work these scientists did, you're in good company. Both Big Bang researcher John Mather and genetic scientist Andrew Fire admit they have trouble understanding each other's work.

MATHER: "I understood what he said, but I'm at a very much layman's level in understanding what he said about his work. But I'm thrilled that he's doing it."
FIRE: "I similarly am not sure I understand all of it. I had some training as a physicist long ago, but it's lost on me at this point to some extent."
CHIMES: Do you have a sense of the importance of it, though?
FIRE: "I certainly have a sense of the importance of it. I mean, this is work that, as [we] said, we really need to know where we come from and it's an important thing to put ourselves and a lot of things in perspective, to know that this universe has been here a finite time and things change."

Andrew Fire and, before him, John Mather are among this year's Nobel Prize winners. The ceremony is on December 10, the anniversary of the death of Alfred Nobel.

Public health authorities often find that different diseases are clustered together. Cholera and typhus, for example, are both common results of unhygienic water supplies. But in other cases the link is not obvious. Malaria and AIDS are two of the most devastating diseases around, and many areas have high rates of both. The malaria parasite is spread by mosquitoes, and HIV is typically spread through sex or when intravenous drug users share needles. But as we hear from health reporter Rose Hoban, a new study conducted in Kenya has shed new light on the connection.

HOBAN: In many parts of the world with high HIV infection rates, malaria is also endemic. For some time, scientists have suspected that each of the two diseases contributes to the other's spread. Now researchers from the University of Washington have added some statistical weight to this theory. Doctors Laith Abu-Raddad and James Kublin studied several hundred people with HIV who live in the Kenyan city of Kisumu. They found that when people with HIV get malaria, the count of human immunodeficiency viruses in their bloodstream increases seven-fold. Doctor Abu-Raddad:

ABU RADDAD: "Now we know that if a person has more viruses within his body, he's more likely to transmit these viruses to other people. And so, actually, malaria can make HIV spread more because it allows people to be more infectious."

HOBAN: The researchers also found, not surprisingly, that because HIV weakens or destroys the immune system, people with HIV were more susceptible to contracting malaria — as well as many other infectious diseases. Abu-raddad says that using these findings, he was able to calculate that in terms of infections from both diseases in kisumu over the past 25 years, the HIV-malaria interaction has taken a significant toll on public health:

ABU-RADDAD: "We estimated that 5 percent of all HIV infections are actually due to malaria. So over 25 years, this translates to eight thousand five hundred HIV cases who get their HIV because of malaria. This also resulted in almost a million additional malaria cases in Kisumu alone over 25 years."

HOBAN: Abu-Raddad compares the confluence of the two diseases to a clash of elephants.

ABU-RADDAD: "So there are 40 million people infected with HIV/AIDS in the world and there actually 500 million malaria cases as well. So these two elephants could clash between each other and in fact they do in Africa because the areas that have HIV also have malaria."

TEXT: Abu Raddad says their paper, which appears in this week's issue of the journal Science, recommends that people who are receiving anti-retroviral medications to fight their HIV should also be treated phophylactically against malaria. He says his colleague James Kublin is returning to Africa to gather more data so they can refine their disease model and better understand how HIV acts in the body.

A new study published this week concludes that testing for HIV — the virus that causes AIDS — should be routine, and that it is cost-effective to test everyone, regardless of their apparent risk factors.

The study confirms recommendations adopted earlier this year by the U.S. Centers for Disease Control, the CDC, backing it with data showing how money spent in testing will result in additional years of healthy life. The study was based on U.S. data, and as we'll hear in a moment, may not be applicable elsewhere.

The analysis of the cost and benefits of HIV testing came from a team led by Dr. David Paltiel of Yale University medical school.

PALTIEL: "And what we found is that, in fact, yes, voluntary screening for HIV should be a part of the medical care for all adults, not just those at high risk. Routine screening is cost-effective, even in communities with very low levels of infection. I mean, we're talking about levels like two in 1,000 people with undiagnosed HIV. And so net/net we find that the study provides very strong support for these new CDC HIV testing guidelines."

Laboratory tests can identify people infected with HIV long before they develop symptoms of AIDS. Paltiel points out the double benefit of knowing your HIV status.

PALTIEL: "Early identification of HIV saves lives in two different ways. It saves and prolongs the survival of persons infected with the disease, and it prevents the transmission to others."

If testing is a good idea, and if resources are scarce — as they always are — you would think that it would make sense to limit testing to groups most likely to be infected. I asked David Paltiel if that’s true.

PALTIEL: "That's what we thought when we first started the study. What astonished us as we conducted the study was that could drive the prevalence down to levels that pretty much reflects the prevalence of HIV in health care settings anywhere in the United States, and still find that it was a good value."

The study was published in the Annals of Internal Medicine. In an editorial, the journal points out that the benefits of testing are based on the assumption that spending $50,000 or less to add a year of healthy life is a bargain. Obviously, cost structures are very different in developing countries, including many that suffer the most from AIDS. As a result, Yale University researcher David Paltiel says, further research is needed to determine the best approach.

PALTIEL: "We are anxious to do this analysis in less-developed countries. The numbers, as you say, are staggering. Only 10 percent, it's estimated, of people living with HIV worldwide are aware of their HIV status. And so, much as this is a problem in the United States, it's only magnified elsewhere in terms of people's inability to access care and their inability to be counseled to prevent the further spread of infection."

And David Paltiel says that some of the obstacles to universal testing are the costs, of course, psychological and cultural barriers, and, in some places, possible legal issues.

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

If you're keeping track of the online world, you probably know about the spectacularly successful website, where users can post videos of a child’s birthday party, a politician acting foolishly, or clips from a TV comedy show.

This week, our Website of the Week is sort of a YouTube for scientists.

PRITSKER: "Journal of visualized experiments is the first online journal presenting biological experiment in a new video format."

Moshe Pritsker is the young, Russian-born scientist who has just started the Journal of Visualized Experiments at Scientists can post short videos explaining — and showing — how they did their experiments as a supplement to the papers they publish in scientific journals that present their findings.

One reason researchers publish their papers in scientific journals is so other scientists can do the same experiments and confirm the published results. But Pritsker says in the biological sciences especially, there usually is not enough space in a journal article to give all the details of how an experiment was set up. So other researchers may find it difficult to reach the same conclusion.

PRITSKER: "And as a result of this phenomena of low reproducibility and science, which leads to a waste of time, waste of resources, frustration in everyday life of every scientist so I was thinking of how to improve it and that was the idea. So the idea is if we would be able to show it instead to write about it."
Q: "The old saying, a picture is worth a thousand words?"
PRITSKER: "Exactly."

For now, Pritsker is focusing on documenting the research procedure, not reporting on their conclusions. Providing a place where scientists can publish their results, not just the procedure they followed, may come later.

PRITSKER: "That will be the next stage for now like to concentrate more on the technical side of the experimental science. But it doesn't matter what, I'm sure that within a few years video publication will become if not dominant that it will have a very important role in scientific publishing."

The site just launched on November 30, and there are only a handful of videos posted so far, so there is plenty of room for growth.

This sounds like the sort of thing that one of the big, mainstream science journals would have thought of, and maybe they did, but Pritsker says he thinks they are too focused on their traditional role of publishing peer-reviewed articles in print.

Check out this novel science publishing concept for yourself at, or get the link from our site,

MUSIC: "Act Naturally" by The Beatles

And presented in living color, this is VOA's science and technology magazine, Our World. I'm Art Chimes in Washington.

Agricultural researchers joined climate scientists this week in Washington to discuss the impact of global warming on the world's food and fiber production. As VOA's Rosanne Skirble reports, at stake are millions of lives and livelihoods in developing countries where crop yields are expected to decline as global temperatures rise.

SKIRBLE: The threat posed by global warming was front and center at the annual meeting of the Consultative Group on International Agricultural Research, better known as the CGIAR, an internationally-funded consortium that runs a global network of agricultural research centers. CG administrators and scientists at the Washington gathering focused on ways to reverse the potentially devastating climate trends they believe threaten the world's food security.

Martin Parry is director of the Jackson Environment Institute of the University of East Anglia in England. He told CG researchers that the conventional response to global warming — taking steps to reduce industrial emissions of CO2 and other planet-warming gases — won't be enough to help farmers in the field.

PARRY: "We are going to have to adapt. There is almost one degree of climate change built into the climate inertia system already. We cannot scrub that away. Even if we chop emissions off at the knees now we are not going to be able to mitigate our way out of the problem."

SKIRBLE: With temperatures projected to rise between 1.5 and 5 degrees Celsius over the next century, the productivity of the world's most important food crops is expected to drop. Farmers will face a shorter growing season and more severe weather events like floods, droughts and storms. Martin Parry says those most affected will be those least able to cope.

PARRY: "Suffice to say that almost all those increases in risk of hunger are projected to be in Africa, and particularly within Africa the poorest countries and within those poorest countries the poorest regions. It's highly specifically geographically located."

SKIRBLE: Cynthia Rosenzweig is leader of the Climate Impacts Research Group for NASA, the U.S. space agency. She says climate data over the last thirty years indicate that many agricultural regions have already warmed.

SKIRBLE: Just three degrees of warming, scientists say, would put as many as 550 million people at risk of hunger and malnutrition. Cynthia Rosenzweig says that in response to this looming threat, farmers — some of whose agricultural practices also contribute to global warming — must both reduce greenhouse emissions and adapt to the climate change.

ROSENZWEIG: "Adaptation and mitigation; [it] is not an either/or [situation]. This is a research challenge to bring together the shorter-term variability with our long-term stresses from climate change. All agriculture is going to be in a situation of a changing climate, no matter how much we mitigate."

SKIRBLE: That would mean new crops that could withstand heat or salt or water. The head of the International Rice Research Institute in the Philippines, Robert Ziegler, says researchers have already created the kind of climate-adapted crops that farmers need.

ZIEGLER: "And both flood tolerant rice and drought tolerant maize are already in the farmers' fields being evaluated."

SKIRBLE: Ziegler says much more work must be done to address agricultural problems created by climate change. He announced to C.G. delegates the formation of a global partnership between the international agricultural and climate change research communities.

ZIEGLER: "I think this is a revolutionary proposition. We have large groups of scientists and researchers who are looking at the issues around development and large groups who are looking at issues around the environment. Rarely do these groups come together if ever except to fight."

SKIRBLE: The meeting to set priorities and chart a plan of action will take place early in 2007. I'm Rosanne Skirble.

This week, scientists studying pictures from Mars said they've seen evidence of water flowing on the Red Planet. Previous images apparently showed evidence of ancient water flows. But the latest images suggest Mars may actually have liquid water on its surface right now.

VOA Science Correspondent David McAlary covered the story. David, where do these pictures come from, and exactly what do they show?

McALARY: They were shot by the 10-year-old Mars Global Surveyor, the satellite that the U.S. space agency NASA, by the way, has recently lost contact with. But these are a comparison of photos taken in 1999 and 2005, and they show clear differences in the terrain in these gullies, that show evidence that some liquid changed the surface of the gully.

CHIMES: The idea of liquid water on Mars now is pretty revolutionary, isn't it? How sure are they that it was water that caused the differences that they're seeing in these pictures?

McALARY: The big issue is the way it flowed. It flowed around objects and it spread into tributaries or fingers, so they knew it was a liquid. But the tone, the very bright tone, suggests it's actually frost that had been water that poured out of the ground and then froze on its way down the side of the gully. So the lightness indicates reflectivity of frost.

CHIMES: Just like you would see it reflecting off on Earth.

McALARY: Exactly.

CHIMES: The U.S. has established a goal of sending astronauts to Mars. If there is liquid water there, would that affect the design of the mission at all?

McALARY: Yes it would. It's actually a good thing to have water on any planet or body we want to visit. That's water we don't have to bring up to support astronauts. So water's a good thing to have everywhere. It makes the future flight much lighter. Less weight that can be either saved in the mission or used for other cargo.

CHIMES: Well before we do go to Mars, the plan is to return to the Moon. The last Apollo astronauts left there more than three decades ago. This week the U.S. space agency NASA announced an ambitious plan for a permanent lunar base with the first flights around 2020. Now how does this Moon base relate to the plans to go on to Mars?

McALARY: It would provide the experience for living on a foreign body, if you will, for a long time, especially in cooperation with people from other nations who are likely to contribute to this.

CHIMES: And this week the Russians indicated they were signing on, or at least saying they were signing on, but I guess having international partners does help spread the cost — and the cost is going to be, well, astronomical. But what other benefits are there to having these sorts of international partnerships?

McALARY: Well before we gloss over cost, cost is really, I think, the significant issue because NASA's budget is essentially flat. And so to get these things done, we have to have, the United States has to have outside help. But in addition to costs, it's going to be ideas becauses the U.S. will provide some basic infrastructure — the transportation to and from the Moon — but all other nations are invited to contribute projects that would support the overall goal.

CHIMES: OK, VOA Science Correspondent David McAlary. Thanks very much, Dave.

McALARY: Nice to be here, Art.

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 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.