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Our World — 22 September 2007


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Straight ahead on "Our World" ... New findings confirm there were feathers on a fierce dinosaur predator ... researchers express confidence in a new drug for tuberculosis ... and reducing the risk of mercury contamination in our food

GILMOUR: "if we can really reduce mercury deposition to ecosystems, we can reduce mercury levels in fish, we can reduce risk to people, and we can reduce risk to the wildlife that eats fish."

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

Another link, now, in the chain tying dinosaurs with today's birds. If you saw the movie Jurassic Park, you'll remember the ferocious dinosaur known as velociraptor. This week, a young American scientist published evidence that velociraptors, like today's songbirds, definitely had feathers and probably used them the way today's birds use theirs. VOA's Jessica Berman reports.

Scientists say they have evidence that a ferocious dinosaur made famous by the movie Jurassic Park definitely had feathers. Experts say the dinosaur, called Velociraptor, had a wing structure just like modern birds. VOA's Jessica Berman reports.

TEXT: A new study by American researcher Alan Turner and his colleagues provides the first conclusive evidence that Velociraptor, a sprinting, vicious dinosaur that lived some 80 million years ago, had feathers.

The velociraptor in the current study is estimated to have been one meter tall, one-and-half meters long and weighed just over thirteen kilograms.

Turner, a graduate student at the American Museum of Natural History in New York and lead author of the study, says velociraptor appears to have been a smaller creature than in Jurassic Park, but just as nasty.

TURNER: "It's sort of as if you scaled up a chicken and then gave it really nasty teeth and big claws on its feet."

BERMAN: Fossils of velociraptor found over the years in Liaoning province in northern China reveal bird-like characteristics. But there haven't been any feathers on the bones unearthed there.

One day, while examining the forearm, or ulna, of a velociraptor dug up in Mongolia in 1998, Turner made an interesting discovery.

TURNER "I felt these couple of bumps along the backside. And it was like, 'Oh, that's very interesting.' And then I kind of let it pass. And then I was thinking about it more later on, and that's when I took it to the high powered microscopes and realized it has all these features that you would expect to see if it was a quill knob."

BERMAN: "The quill knobs found on velociraptor are regularly spaced bumps along the ulna where flight or wing feathers would have been attached."

TURNER: "And when you compare them to the ulna of a bird, you see that they correspond quite closely to these quill knobs. These wouldn't have been flight feathers in the velociraptor, because it's an animal that's much too big to have flown. But it still shows that feathers were attached to the bone there."

Turner thinks velociraptor might have used the feathers for show, to shield nests or to keep itself warm.

He says his team did not find quill knobs on other fossils of the bird-like carnivore, but that doesn't mean, he said, that velociraptor did not have feathers.

The discovery of velociraptor quill knobs is reported in the journal Science. Jessica Berman, VOA News, Washington.

In America we have some of the best medical care in the world, but the same high quality care isn't available to everyone. Government programs insure the elderly and the poor. For the rest, it's usually private health insurance through their job, or else no health insurance at all.

Into our complex and, critics say, unfair system come immigrants, who health policy experts classify as a "vulnerable" group — at increased risk for heath problems and inadequate health care.

The health vulnerability of immigrants is the subject of a paper in the current issue of Health Affairs, a journal that examines health policy issues. Lead author Kathryn Derose of the Rand Corporation in California says some factors — like low income or limited education — can make anyone vulnerable. But immigrants, she said, have some special risks.

DEROSE: "Things like their immigration status, whether they're a citizen or not, naturalized citizen or legal permanent resident versus an undocumented [immigrant]. When they came to this country, because policies have been changing. Where they live in this country can also seem to affect how good their access to care and quality of care is."

That said, there's evidence that immigrants, at least the young ones who come here to work, actually are healthier than their American-born counterparts, at least when they arrive. Over time, however, their health deteriorates. Co-author Nicole Lurie saw that first-hand when she lived in Minneapolis, Minnesota.

LURIE: "Minneapolis has had a lot of different immigrant populations over the years. First lots of southeast Asians — Vietnamese and Hmong communities — and then more recently a huge Somali influx. When I first started taking care of Somali patients you never saw a Somali person who was diabetic. Now, something like half of Somalis in that community are diabetic because they've adopted really crummy American, western health habits."

Immigrants are a pretty diverse group, including naturalized citizens, and both legal and undocumented non-citizens. Their legal status, in fact, plays a big role in their health status, say the authors, because their legal status may limit their access to various government services, or to jobs with health-related benefits. The recent increase in anti-immigrant sentiment may result in more limitations.

In their jobs, immigrants may be engineers or nannies or farm workers, and they come from almost every country on Earth. Their socioeconomic status, too, is an important factor in how healthy they are and in how well they are treated when they get sick. Income, education and English proficiency are also part of the mix. For example, Spanish-speakers are more likely to find a Spanish-speaking doctor in Los Angeles or Dallas than in a small town in Idaho or Maine, far from the Mexican border.

Among these various risk factors, one seems missing: the country of origin. In fact, co-author Nicole Lurie stresses that their diversity make it hard to generalize about the health vulnerability of immigrants from any one country.

LURIE: "But I also suspect that what we're going to find is that where immigrants go is also going to have a lot to do with how they do. So if people, regardless of where they come from, end up in places where there are good school systems and their kids can get educated and can learn English and there are job opportunities, they're going to do better than people who aren't."

One recommendation the authors have is expanding access to health insurance, whether through private providers or through government programs. That recommendation could also apply to everyone who is uninsured. But lead author Kathryn Derose she says immigrants have certain unique needs that go beyond the medical care itself.

DEROSE: "And then there are things having to do with the limited English proficiency. There are laws that hospitals and clinics that receive federal funding are obligated to provide care in their language assistance, but there's often little enforcement of that. And then things like expanding and strengthening the medical safety net: hospitals and clinics that care for a large portion of the uninsured in communities and often for immigrants."

Kathryn Derose and her colleagues note that in a political environment where many Americans feel the country is being overrun with illegal immigrants, actions taken to curtail illegal immigration may have serious health consequences for all immigrants, regardless of their legal status.

The World Health Organization says there are some 9 million new tuberculosis cases each year, and TB kills more than a million and a half people annually — 90 percent of them in developing countries. But also troubling, as we hear from health reporter Rose Hoban, is the fact that established medicines are facing an uphill battle against new drug-resistant strains of TB.

HOBAN: Yet there is little research into new medications to fight TB, says Doctor Richard Chaisson, a professor at the Johns Hopkins Medical School. Chaisson says that's largely because pharmaceutical companies don't see a profitable market for tuberculosis drugs.

CHAISSON: "The current treatment for tuberculosis has been around for 35 years and we know that while it's good, it's not good enough. We're looking for new treatments for TB that will shorten the time that it takes to cure people, and to have drugs that work against resistant strains of TB that have arisen in recent years."

HOBAN: Chaisson has been examining a new antibiotic which he thinks has TB-fighting potential. Moxifloxacin came onto the market about eight years ago, and has been used to treat other respiratory diseases. He and his colleagues tested it and found the drug could kill TB in the lab. Now they have tested it on close to 200 TB patients in Brazil. Chaisson found those on moxifloxacin had a better and a faster response than patients getting standard treatments.

CHAISSON: "Within a week we saw the differences and by the end of two months of treatment we've found that the patients on moxifloxacin were significantly more likely to have responded to the treatment. It was about 25% higher cure rate at that point with moxifloxacin than with the standard treatment."

HOBAN: And Chaisson says moxifloxacin had few side effects.

CHAISSON: "We gave it for eight weeks and there was some worry that there will be side effects that we hadn't previously seen. But fortunately there weren't any."

HOBAN: The biggest expense in treating TB is the cost of doctors and nurses to monitor patients over the typical six-month course of therapy, not the cost of medications. Even so, the drug's manufacturer, Bayer, has agreed that if moxifloxacin proves to be effective against tuberculosis, the company will provide the drug at a much reduced rate to TB patients.

Chaisson's research was funded by a U.S. government program that focuses on so-called orphan diseases — diseases that drug companies generally do not have an interest in. He presented his research recently at the Interscience Conference on Antimicrobial Agents and Chemotherapy in Chicago. I'm Rose Hoban.

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

The 2008 U.S. presidential election is still more than a year away but, as you may have heard, the election campaign has been going on for months. More than ever before, voters are using the Internet to inform themselves about the issues, the candidates, and how the candidates are financing their campaigns.

RITSCH: "OpenSecrets.org is the online incarnation of a project that the Center for Responsive Politics has been doing for about two decades now: following the money in U.S. elections, figuring out who's financing U.S. politicians and to what extent, and what they might be getting in return for their money."

Spokesman Massie Ritsch says OpenSecrets.org gets its information from the federal government, which collects the data. The Federal Election Commission has much of this information on its website, but Ritsch says OpenSecrets.org provides added value to the raw data, for example by classifying contributions by industry.

RITSCH: "And that's important because if you're looking at drug prices or the loan rates for students attending universities, you really need to know how the industries that are involved in those issues have supported politicians. And that's the work that we do, is aggregating the money from millions of donations by industry, by geography, and a host of other ways, and putting it up in a really user-friendly format."

OpenSecrets.org won its fourth Webby award this year as best politics site on the Internet, in part, perhaps, because the site tracks not just presidential and congressional candidates, but state and local election contributions, too. Massie Ritsch says government disclosure laws in the United States combined with easy Web access make this a unique resource.

RITSCH: "There are many other countries that collect the information, but from my experience and talking to people, usually that information is compiled on paper and collected and stored in one government building, and unless you're there you don't have access to it. Through our website, OpenSecrets.org, as well as the government's website, people can get to this information no matter where they are."

Helping Americans "follow the money" in politics, our Website of the Week is OpenSecrets.org, or get the link from our site, voanews.com/ourworld.

MUSIC: Solomon Burke — "Honey Where's The Money Gone"

Full disclosure: we take no private contributions at VOA's science and technology magazine, Our World. I'm Art Chimes in Washington.

The United States produces one-quarter of the world's greenhouse gas emissions, more than any other country. But China is expected to surpass that total by 2009, more than a decade earlier than previously predicted. As VOA's Rosanne Skirble reports, China's environmental problems are getting more international attention lately, especially with the approach of the 2008 Olympics.

SKIRBLE: China's economy is growing by more than ten percent a year. But this booming industrial success has come at great cost. Chinese cities are now among the world's most polluted. Acid rain falls on one-third of its land. And despite having some of the world's largest water reserves, two-thirds of China's cities have less water than they need because of overuse, pollution and bad management.

The crisis stems, in part, from a decentralized government that values economic growth over environmental protection, according to Elizabeth Economy. She is director for Asia Studies at the Council on Foreign Relations.

In its publication, Foreign Affairs, she writes that local officials are autonomous and have no economic or political incentives to do the right thing.

ECONOMY: "You have fines that are set too low. Factories simply would rather pollute and pay fines that actually put into place pollution prevention technologies that are more costly up front."

SKIRBLE: Economy says local leaders are more likely to put environmental safeguards in place when pollution problems begin to hurt economic growth.

ECONOMY: "For example, they don't have enough water to run their factories. Now that's a problem. And that happened in Xian in 2004 or 2005. So that's the kind of thing that can be wakeup call for a local official. Things have to change at that point. If in fact you see that all your crops are polluted and spoiled then you need to do something about the water pollution."

SKIRBLE: Coal is the engine that powers China's economy. This dirtiest of all fossil fuels supplies two-thirds of the country's energy needs. While Beijing has set targets to reduce its emissions, they largely go unmet. And as a developing country, it's under no obligation to conform to restrictions under the Kyoto Protocol, the United Nations global treaty on climate change.

China has become a reluctant player in the world climate debate. And Elizabeth Economy says, unless Washington changes its own global warming policies, it will have little credibility or leverage to push Beijing forward.

ECONOMY: "If you look in the past at what has brought China to the table, on ozone depletion for example, you had to have a strong international consensus, and we don't have that right now. So, it's not that China never agrees to sign on to international environmental agreements. It will. But the circumstances surrounding it have to be right. And until those circumstances are right, I think China is going to do as little as possible."

SKIRBLE: She sees little progress toward fulfilling Beijing's promise of a green Olympics in 2008.

ECONOMY: "That clearly hasn't happened and frankly it hasn't happened for Beijing alone. So we have doctors now saying if you have got respiratory problems, stay home. The Chinese have now said we are not going to be able to provide clean water to everybody in Beijing, just for the Olympic Village."

SKIRBLE: Elizabeth Economy says China cannot go green without political reform. The loudest voice for that cause comes from non-governmental organizations, which have grown from a handful ten years ago to many thousands today. These groups are both tolerated by Beijing and feared as a potential source for civil unrest.

ECONOMY: "But, I think between the development of grassroots activism, not just on the environment but on a lot of other issues, as well as the beginnings of some local elections and people who are pushing for electoral reform, I think that change will come."

SKIRBLE: Economy notes that there is some agreement within government agencies and the Chinese Communist party, that reforms must take place. What's lacking, she says, are leaders with the vision to make changes in how business is done. When that happens, she says, China — and the rest of the world — will breathe a lot easier. I'm Rosanne Skirble.

Another dangerous air pollutant emitted by coal-fired power plants is mercury — a common and widely-used metal that's known to cause serious human health problems. Most human exposure to mercury comes from eating fish and shellfish contaminated by industrial air pollution. But little was known about how quickly fish would respond to changes in mercury inputs from the atmosphere. A joint U.S.-Canada study suggests that reducing air pollution will make a difference, as Véronique LaCapra reports.

LaCAPRA: Coal-fired electric power plants are the largest source of mercury in U.S. air pollution, emitting about 40 percent of the toxin. Other major sources include industrial boilers, hazardous waste incineration, and chlorine production.

Some of this airborne mercury gets into lakes and other bodies of water, and makes its way up the food chain. Mercury concentrations increase as they move up the chain, so the top predators — fish that eat other fish — have the highest levels of contamination.

Most human exposure to mercury comes from eating this contaminated fish. But is that mercury from current air pollution, or from soil and sediment, where mercury has been deposited for more than a century, since the start of the industrial revolution?

GILMOUR: "The reason that's important is because if this year's mercury and last year's mercury are mostly what's in the fish, then if we change deposition levels, we can reduce mercury levels in fish. But if this long history of mercury contamination is contributing to mercury in fish, then reducing mercury deposition now isn't going to have a whole lot of impact for a long time, because we're making a small change in this huge amount of mercury that's already in the system.

LaCAPRA: Cynthia Gilmour is a microbial ecologist at the Smithsonian Environmental Research Center in Maryland. She is part of a team of about 50 researchers from the U.S. and Canada, who have been studying how freshwater fish respond to changes in mercury deposition — the mercury that gets into freshwater from air pollution. They used an unusual experimental approach: they added mercury to an entire lake and its surrounding watershed.

GILMOUR: "This is something that's never been done before. We dosed the wetland and the forest from an agricultural spray plane. So we sprayed the mercury onto the whole system just like you would spray a crop. And we were very careful to do it during light rain storms, so it mimicked what would happen when mercury is really deposited to ecosystems in rain."

LaCAPRA: The researchers also added mercury directly to the lake itself. But they needed a way to distinguish what they were adding, from the mercury that was already there.

GILMOUR: "Mercury has seven natural isotopes."

LaCAPRA: Isotopes are forms of an element that have different atomic weights, but that are otherwise chemically similar.

GILMOUR: "And what we can do is pick out an individual isotope of mercury, and enrich that isotope, and then we can use that to dose the system. And so it gives us a chemical signature that [allows us to] trace the mercury that we added to the lake, separately from the mercury that was already there."

LaCAPRA: What Gilmour and her colleagues found was that the mercury they added directly to the lake made its way up the food chain and into the fish within just a few years.

GILMOUR: "So that's the good news part of the study, that if we change deposition to the surface of lakes, we'll change the levels of mercury in the fish. That means that if we can really reduce mercury deposition to ecosystems, we can reduce mercury levels in fish, we can reduce risk to people, and we can reduce risk to the wildlife that eats fish."

LaCAPRA: The "bad news," as Gilmour puts it, is that in the seven years since the study began, the mercury added to the area around the lake never showed up in the fish at all; it stayed trapped in the trees and shrubs, where it landed. That finding suggests that historical mercury contamination in soils and vegetation will be around for many years to come, and could eventually work its way up the food chain and into the fish.

GILMOUR: "So we expect a two-phase response, a partial fast response, and a much longer complete response."

LaCAPRA: In 2005, the U.S. Environmental Protection Agency passed the Clean Air Mercury Rule, limiting mercury emissions from coal-fired power plants. If Gilmour and her colleagues are correct, less mercury in the air should mean less mercury in fish — at least, in freshwater systems. Whether the same would be true for swordfish, sharks, and other marine fish is difficult to predict.

The next step in the research is to watch what happens as the lake recovers, and to see whether mercury concentrations in fish really do decline, as expected. I'm Véronique LaCapra.

That's our show for this week. We're always interested in your comments or your science questions. Email us at ourworld@voanews.com. 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 voanews.com/ourworld or on your radio next Saturday and Sunday as we check out the latest in science and technology ... in Our World.

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