VOA标准英语2010年-Our World - 1 May 2010（在线收听）

This week on Our World:  Geneticists find new clues to a puzzling disease ... the fungus that's killing off bats ... and the coming increase in hazardous electronic waste...

WILLIAMS:  "By around 2030, we're looking at potentially a billion e-waste computers every year with about two-thirds of those from the developing world."

Those stories, what ancient mummies can tell us, and more...

I'm Art Chimes. Welcome to VOA's science and technology magazine, "Our World."

Environment Plays Major Role in Development of Multiple Sclerosis

A new study concludes that young adults genetically predisposed to developing multiple sclerosis, a crippling neurodegenerative disease, could be at greater risk of developing the condition because of environmental factors. VOA's Jessica Berman reports that scientists found that some people with the DNA abnormalities for MS never develop the disease.

BERMAN:  Multiple sclerosis, or M.S.,affects an estimated 1.2 million people worldwide. The progressive disease leaves many of its victims unable to walk unassisted.  It mostly strikes women of northern European descent.

Researchers have long suspected that M.S. is caused in people who are predisposed to the disease by a combination of inherited genetic mutations and an environmental trigger, such as a viral infection or living in temperate climates.

Now, a team of scientists has discovered that some people with genetic mutations for M.S. in their DNA never develop the disease.  They conducted an exhaustive genetic analysis of three sets of identical twins — including two female pairs — and found no biological explanation for why, in 30 percent of the cases, one twin developed MS and the other one did not.

Stephen Kingsmore is a genetic researcher at the National Center for Genome Resources in Santa Fe, New Mexico who led the study.

KINGSMORE:  "This points to some novel and fairly powerful effect on top of the genetic risk factors which seems to spell out whether you're going to develop multiple sclerosis."

While the genetic analysis revealed nothing at the genetic level that would cause one twin to develop MS while sparing the other, Kingsmore says the study at least confirms that MS is triggered by a combination of environmental and genetic risk factors.

KINGSMORE:  "We don't really know why one of them didn't develop multiple sclerosis, given that they both had the same (biological) risk factors and indeed they both had much of the same environment.  Because if you think about it, they would have been born on the same day to the same parents and lived in the same house and had all of the same childhood environmental things in common."

But scientists remain clueless as to what, precisely, that "powerful effect" might be.  Kingsmore says the genetic map they created of the M.S. twins is the first complete DNA analysis of identical twin pairs, women and an autoimmune disease. 

Kingsmore says the work could help scientists interested in other autoimmune diseases, such as lupus or juvenile diabetes, delve deeper into their causes.

An article describing the study and the full genetic sequence of multiple sclerosis is published this week in the journal Nature.

Jessica Berman, VOA News, Washington

Ancient Mummies Shed Light on Evolution of Modern Diseases

Mummies have been the inspiration for dozens of Hollywood horror flicks... and a glimpse into the distant past for archeologists. But a renowned mummy expert says these carefully preserved human bodies actually have an important role to play in the modern world: helping doctors understand the diseases that have plagued humans for thousands of years. Naomi Seck reports.

SECK:  Back in 2005, when Frank Ruhli was trying to figure out how ancient Egypt's famous boy pharaoh, King Tut, died, he used CT scans.

Now, Ruhli says, the new technology to screen some airline passengers for explosives can provide even more information.

RUHLI:  "By applying this technology on top of another technology, it may help you to look differently at the specimen. By using this Terahertz imaging, you eventually may be able to look at the substances within the mummy, for example the embalming liquid used in the Egyptian way of embalming. There you can actually do substance analysis which you can't really do by conventional x-ray."

SECK:  Terahertz imaging is also known as "full body scan" technology.

Ruhli and his team of researchers at the Swiss Mummy Institute have just completed the first feasibility study of how they could use the technology to reveal a mummy's secrets, without damaging the mummy.

He says the images they have gathered with the terahertz scans are very promising.

And he says the results are not just interesting for historians.

RUHLI:  "More and more, there are actually people aware of the fact if we want to know more about medicine or actually how to treat patients with all these health care issues, we have to look to the past as well."

SECK:   The most famous mummies are the Egyptian ones, which were carefully dried out with salts, treated with oils and resins and wrapped in linen before being placed in a coffin.

But Ruhli says there are mummies from every historical era, from everywhere in the world. These so-called "natural mummies" were preserved accidentally.

However it happens, the mummification process preserves the body's soft tissue long after it would normally have decomposed ... and with it, the virus or bacteria that may have caused the person to die.

Ruhli, who is a medical doctor as well as a paleopathologist, says looking back can help scientists look forward, by revealing how the disease evolved over time.

They can even map a pathogen's genetic code, which changes from generation to generation.

Ruhli notes researchers used that technique to study the evolution of the tuberculosis bacteria from 2,000-year-old mummified tissue to modern-day strains.

Ruhli says such research could never replace modern clinical studies. But he says taking the long view can help provide insights scientists might miss in a snapshot from a single moment in time.

Ruhli, who was reached via Skype, presented his argument to scientists and doctors this week at a conference on experimental biology.

I'm Naomi Seck.

Developing Countries to General More Electronic Waste

For years now we've been hearing about e-waste — electronic waste, typically generated when users in rich countries trade in their old computers or mobile phones for newer models. The problem is, what happens to those old devices, which can include toxic materials? Too often, they're shipped to developing countries, supposedly for reuse or recycling. Now, a new study suggests that in the coming years, the source of e-waste will be changing.

I spoke with the lead author of the study, Prof. Eric Williams of Arizona State University, and I asked him first why we should be worried about e-waste.

WILLIAMS:  "There are two main reasons to be concerned about e-waste. One is that e-waste does contain some toxic materials, such as lead. The other concern about e-waste relates partly to the toxic content, but also partly to something else, and that is 'backyard recycling' in the developing world.

"And what's happening here is that a lot of the waste that we throw away in the U.S. ends up being shipped overseas to China, India, and other developing countries, where it is processed by an informal, backyard reuse-recycling industry.

"And some of these components, when you recycle them with primitive processes cause really bad environmental impacts. In particular, there's circuit boards and wires. Circuit boards contain valuable quantities of gold and copper and other precious metals. And the recyclers want to get those materials out.

"And so what they'll do in the developing world is that they'll  use very, very primitive processes using cyanide and also acid -"

Q:  And they're doing this without the kind of protections that you would expect -

WILLIAMS:  "Without any protections whatsoever. We're looking at open barrels full of cyanide, another barrel with acid, people dipping stuff in."

Q:  So you your paper you're talking about, but you're also talking about how the growth of the use of personal computers in countries that historically have been  considered developing countries is going to — I don't think it's hyperbole to say it's going to explode in the coming years. How does that contribute to the problem of e-waste?

WILLIAMS:  "Yes, well, the way that the international e-waste issue has been thought of is as a trade problem. And thus, you'd think that, well, we have this trade problem, [so] what we need to do is ban the trade.

"Well, in the study, the paper that I recently finished, the question that we asked there is, what are the numbers of e-waste computers being generated around the world. And the answer is that, within six to eight years, there are going to be more e-waste computers generated in the developing world that the developed [world]. And the growth rates after that are going to be much faster in the developing world than in the developed. And so this is strongly arguing that there is a domestic stream of e-waste in the developing world  that is growing rapidly and that dealing with this problem, it's not just about the trade, you really have to think about how we deal with the informal recycling, the backyard recycling problem more directly.

"By around 2030, we're looking at potentially a billion e-waste computers every year with about two-thirds of those from the developing world."

Q:  A billion computers going into the waste stream.

WILLIAMS:  "Potentially."

Q:  That's a lot.

WILLIAMS:  "Yeah."

Q:  So, what is the take-home message and the policy implications? How would you summarize that?

WILLIAMS:  "There has been basically very little policy activity to deal with informal recycling or backyard recycling in the developing world directly. The premise has been, OK, let's stop the trade and let's remove toxics from the materials and that will solve the problem. And what this analysis is going to tell us is that this will not solve the problem. And so we need to think about policy now to directly address informal recycling."

If banning shipments of e-waste doesn't work, Williams says what might work are economic incentives, such as government programs to buy e-waste to make it more profitable for those backyard recyclers to sell parts into a proper, regulated recycling facility.

The paper by Eric Williams and his colleagues from China's Nankai University, is published in the journal "Environmental Science and Technology," published by the American Chemical Society.

Website of the Week Feautures Development Data from the World Bank

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

For years, the World Bank has been one of the world's leading collectors of data. All kinds of information: life expectancy, literacy rates, unemployment, exports, water pollution — the list is nearly endless.

Now, a new World Bank website brings those numbers together in one place.

FIX:   "The data website, which is data.worldbank.org, is the central platform for all of the development data from the Bank, and the focus of this is to make the data open, accessible, and searchable."

Richard Fix is a spokesman for the World Bank data group, which has just launched its new website. At data.worldbank.org, you can see all the metrics for a given country, or compare different countries on the same indicator, with some historical data going back as far as 1960.

But Fix says the site's real strength is that users can download and manipulate the data, not just browse it passively.

FIX:   "You get people who are quite handy with the systems and developing applications, and they use the data and mash-up the data with other pieces of data and raise questions that maybe haven't been raised before, or point to answers that we hadn't seen before."

World development indicators online at data.worldbank.org, or get the link to this and hundreds of other Websites of the Week from our site, voanews.com.

MUSIC:   Ali Friend — "Boucing Baby"

It's "Our World," our science and technology mashup from VOA News. I'm Art Chimes in Washington. 

White-nose Syndrome Bat Fungus May Have Originated in Europe

Scientists are racing to find a way to combat a fungus that's killing bats in the United States. More than a million bats have died so far. Scientists believe entire hibernating bat species could be wiped out within two decades. Laura Iiyama reports the cause might have come from a far-away country.

IIYAMA:  Biologist Scott Darling knew something was wrong in a recent winter when he got several calls at his Fish and Wildlife office in Vermont. People told him about hundreds of bats flying in the air and dying in the snow. During winter, the furry mammals should be hibernating.

He went to Aeolus cave. It's where the bats in the area should be crowded together on the walls and ceiling.

DARLING:  "Aeolus cave quickly became a morgue. Bats freezing to death in clusters just outside the cave entrance. Most of the bats flew out of the cave onto the landscape to certain death."

IIYAMA:  Where 200- to 300,000 bats had hibernated just four years ago, this year there are just a couple hundred.

The bats had been hit by white nose syndrome.

The white powdery fungus was first noticed on bats in New York State in 2006. It's spread into Ontario, Canada, and as far south as Tennessee.

The fungus is not directly killing the bats.

Thomas Kunz is a professor at Boston University. He suspects the fungus keeps waking-up the hibernating bats.

KUNZ:  "It may be simply the irritation from the fungus that is causing [them to wake up, just like] if you have athlete's feet, it itches."

IIYAMA:  Instead of hibernating — surviving on their fat reserves — the bats keep waking-up. They burn off the fat. They get too thin. And they die.

Word spread about the fungus. Thomas Kunz says some scientists recalled seeing a white fungus on bats elsewhere:

KUNZ:  "Bat biologists in Europe have observed and reported that there are bats that do have the fungus, although it doesn't seem to be killing them."

Scientists think someone visited a cave in Europe. Spores from the fungus got on clothing or shoes. Then, that person wore the same shoes or clothing in a cave in the U.S. The spores were picked-up by the bats.

Often 90 percent of the bats are killed-off after the first appearance of the fungus. And Kunz says that may have been what happened to bats in Europe because we don't find as many bats in European caves as there have been in North American caves:

KUNZ:  "Now it's very possible that in historic times there were large numbers of hibernating bats in Europe, and ... these were the survivors that may be resistant to the fungus."

So the arrival of the fungus may mean U.S. bat species will permanently drop in numbers, like the bats in Europe.

There's no treatment for white nose syndrome. And even if a cure is found, it will be a very long time — centuries — before the bats recover. Bats reproduce slowly. The females have only one pup, one baby bat, per year. And there are over a million bats dead so far.

For The Environment Report, I'm Laura Iiyama.

Support for the Environment Report comes from the Park Foundation, the Gaylord and Dorothy Donnelly Foundation, and the Great Lakes Fishery Trust. You can find more stories and post your comments at EnvironmentReport.org.

Science cafés bring researchers into conversation with the community

I happen to like learning about science, but for a lot of people, it can seem complicated and overwhelming. And frankly, scientists often have a hard time explaining their work in language that non-scientists understand. But, as reporter Véronique LaCapra discovered, there is a movement to bring scientists out of the lab and into the community — for a dialogue, over food and drink.

LaCAPRA:  Most people learn about science in school, from the media, or on the internet. But at a science café, they get to learn about it straight from the scientists themselves.

For the past four years, Al Wiman has organized a monthly science café for the Saint Louis Science Center in Missouri.

WIMAN:  "A science café, it's a concept that actually started in Europe, and it was an idea to get scientists engaged in an informal conversation with the general public."

LaCAPRA:  Wiman says part of what makes science cafés successful is where that conversation takes place:

WIMAN:  "We have it in the lower level of Herbie's restaurant in the Central West End."

LaCAPRA:  There are now more than a hundred science cafés at bars and restaurants throughout the United States. They attract anywhere from a handful to over a hundred people, depending on the topic.

St. Louis has two science cafés. The second one — sponsored by Washington University — meets once a month during the academic year at a bar called the Schlafly Bottleworks.

LaCAPRA:  Organizer Cynthia Wichelman says "Science on Tap" features Washington University professors talking about their research. The events draw a diverse audience:

WICHELMAN:      "We have people who are professionals that range from engineers and physicians, to people that just have an interest in science and may be retired, may not be employed, may be students, and have just an interest in learning more."

LaCAPRA:  So what brings people out to a bar to talk about science?

STUART:  "I like the atmosphere: it's fun to learn things, and enjoy a good beer."

SMOTHERS:  "I was actually really lousy in science class, so now I'm picking up the information as I can get it."
Q:  "So did the fact that this is at a bar kind of help?"
SMOTHERS: "Very much!" [laughs]

ROGERS:  "I would call this a civilized education."

PLESS:  "Why aren't more science talks in a bar, right? Like this is the place where you learn and you ask and you understand things most quickly, instead of a lecture where it's really just a one-way thing."

LaCAPRA:  The topics discussed at these science cafés are as varied as scientific research itself: from black holes to biological clocks to botany. But the evening really kicks into high gear after the scientist's presentation ends, when the audience gets to start the conversation.

"Is it still a question as to whether there is a lot more plant diversity in the Andes versus the Amazon?"
"If you're right, what is the origin of the magnetic fields?"
"What is their number one objection to what you're saying?"

LaCAPRA:  And the questions keep coming — sometimes going on for longer than the presentation itself.

But the scientists don't seem to mind.

Ivan Jimenez of the Missouri Botanical Garden says he appreciated the chance to talk about his work with people outside the scientific community.

JIMENEZ:  "Scientists often talk to scientists, not very often to non-scientists, so that's kind of exciting, fun." [laughs] "Challenging."

LaCAPRA:  But at the science cafés in St. Louis, scientists and non-scientists alike seem up to the challenge.

For Our World, I'm Véronique LaCapra, in Saint Louis.

'Our World' Host Art Chimes' Last Show

One more bit of business before we go.

This is Our World program number 534, and this is my last show.

Our World first went on the air 10 years ago as a weekly, feature-oriented science magazine. I've been at this microphone since 2004, and I've tried to bring more of a news focus to the show.

I sometimes refer to Our World as my radio show, but it's really our show.  What you hear each week is the collective product of a bunch of talented and dedicated people. They include reporters Jessica Berman, Rosanne Skirble, Steve Baragona, and Adam Phillips. We couldn't do it without our many freelance contributors, and our freelance coordinator, Faith Lapidus, who is also one terrific editor. Bob Doughty, and before him, Eva Nenicka have been the wizards in the control room who make the program sound as good as it does. Rob Sivak is the show's editor who somehow also finds time to be an energetic source of interesting story ideas. And of course, we wouldn't be here if it weren't for you, listening on the radio, checking us out online, and writing in. I plead guilty to not answering every letter or email, but I read them all, and I thank you for writing.

I've been at VOA since the early 1980s, and I've been lucky enough to have had some really great jobs. I was a correspondent in Prague and Jerusalem, a web editor, economics reporter, and of course I've covered science. I've met and interviewed prime ministers and astronauts and Nobel laureates. But I have to say these last six years have been special. People ask me what I like best about my job and I tell them I get to talk to really smart people, and I learn something new every day.

This show will continue, of course, so please stay tuned as VOA's science and technology magazine, "Our World," moves into its second decade.

MUSIC: "Our World" theme

That's our show for this week.

Thanks for listening, and please stay in touch. You can email us at [email protected].

Our program is edited by Rob Sivak. Bob Doughty 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.