Our World ?? 24 October 2009


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23 October 2009


MUSIC: "Our World" theme

This week on Our World: A progress report on vaccinating children ... a way to invigorate high school science teaching ... and turning spoiled food into fuel ...

MORRISSEY: "That farmer could literally harvest his or her entire crop, send it to the ethanol plant, and at least get something out of it instead of taking a complete loss."

Those stories, experts advise NASA on our next move in space exploration, and more.

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




More Children Vaccinated against Killer Diseases

A new report finds significant progress has been made in immunizing the world's children against preventable, killer diseases. However, it says millions of children still do not have access to these life-saving vaccines. The report, called State of the World's Vaccines and Immunization, is produced jointly by the World Health Organization, the United Nations Children's Fund (UNICEF) and the World Bank. Lisa Schlein reports from Geneva.

SCHLEIN: The report says immunization rates are at record highs and vaccine development is booming, worldwide. It says 106 million infants were vaccinated against DTP -- diphtheria, tetanus, and pertussis or whooping cough ?? last year.

One of the biggest success stories involves measles. The report says measles deaths worldwide fell by 74 percent between 2000 and 2007. The largest reductions occurred in Africa.

Alison Brunier is communications officer for the department of Immunization, Vaccines, and Biologicals at the World Health Organization.

She tells VOA vaccines are available against 120 diseases, a record number. And new vaccines are coming through the pipeline.

BRUNIER: "During the last years, there have been new vaccines put on the market against rotavirus diarrhea, against meningococcal meningitis, against pneumococcal disease, and also against human papilloma virus, a cervical cancer vaccine."

SCHLEIN: In addition, she says more than 80 new products are in late-stage clinical testing, including more than 30 that target diseases, such as dengue and malaria, for which no vaccine currently exists.

SCHLEIN: Brunier notes life-saving vaccines are now common in wealthy countries. She says, unfortunately, these same vaccines still do not reach millions of children who live in poor countries.

BRUNIER: "Some of the basic challenges relate to issues such as difficult geographical situations, political strife, insufficient basic health care, infrastructure in countries."

SCHLEIN: Health officials say at least an additional $1 billion a year will be needed to make sure new and existing vaccines will be delivered to all children in the 72 poorest countries.

The report says manufacturers in developing countries now are meeting 86 percent of the global demand for traditional vaccines.

Lisa Schlein for VOA News, Geneva.



Experts See Different Path for US Space Exploration

A panel of experts has delivered its final report assessing America's options for future human space exploration.

The sobering report says there isn't enough money in NASA's current and proposed budgets to do what the space agency plans to do in the coming years, including a return to the Moon. Chairman Norman Augustine briefed reporters on Thursday.

AUGUSTINE: "The premier finding of the committee is that the human space flight program that the United States is currently pursuing is one that is on an unsustainable trajectory. We say that because of a mismatch between the scope of the program and the funds to support the program."

The committee was asked to come up with some realistic options for space exploration in the coming decades, rather than to make one particular recommendation. But some common elements emerged. Most of the options include using commercial vendors to get astronauts into Earth orbit, leaving NASA to do more difficult and cutting-edge work. That would probably mean scrapping the Ares I rocket that NASA has been developing, and which is set for its first test flight on Tuesday. The committee also wants NASA to fly the space shuttle at least into 2011, rather than grounding it a year from now, which is the current plan.

Some of the options outlined by the committee focus on a return to the moon, but there seemed to be an unstated preference for what they call the "flexible path" options ?? including flying to an asteroid or going to Mars, but not landing there. Committee member Ed Crawley is an engineering professor at MIT. He described some of the advantages of the flexible path approach.

CRAWLEY: "What you build is the booster and the capsule, and then you can start going places. You can go on an orbital flight around the moon. Then you can build a little bit more, an in-space hab, and you can go to a near-earth object. You know, what this flexible path does is it allows us to take some of the components that you would build first anyway ?? the heavy booster and the capsule ?? and start exploring while we're building the lunar landing system and the lunar surface system, so that when they become available, it's time to go to the Moon."

Committee chairman Norman Augustine is a retired aerospace industry executive and a veteran of this sort of expert advisory commission. He was asked if he thought the committee's 150-page report would really have an impact. He acknowledged there are a lot of other things going on in Washington right now ?? a major health care debate, an economic crisis, and a couple of wars.

AUGUSTINE: "But I've worked on a number of these studies where I think we've had a major impact. And I worked on an awful lot of them where we had no impact. And I guess only time will tell."

The Augustine committee report, called "Seeking a Human Spaceflight Program Worthy of a Great Nation," is on the NASA website, and we'll have a link on our site, voanews.com/ourworld.



Personalized Treatments My Reduce Tuberculosis Threat

Researchers at the World Health Organization say efforts to bring the global tuberculosis epidemic under control are being slowed by the persistence of drug-resistant forms of TB. But in a new report, WHO experts predict these dangerous strains of tuberculosis may eventually be eradicated with more careful use of antibiotics. VOA's Jessica Berman explains.


BERMAN: Antibiotics are still effective in treating most cases of tuberculosis, but widespread misuse of antibiotics has fostered the growth of drug-resistant forms of TB, as well as other dangerous bacteria.

Cases of multi-drug-resistant, or MDR tuberculosis have been reported in dozens of countries where the bacterium no longer succumbs to the two main anti-TB drugs, isoniazid and rifampicin.

Using data on multi-drug resistant TB from ten countries, Christopher Dye of the WHO's office on AIDS, Tuberculosis and Malaria, studied whether it's possible to contain the spread of MDR TB using current drug therapies.

DYE: "Once the genie is out of the bottle, can we put it back in again? And the encouraging result from our study is that, provided we use the drugs in the right way, we can actually reverse the spread of multi-drug-resistant TB."

BERMAN: Dye and his colleague Brian Williams analyzed the incidence of MDR-TB since the WHO finalized a comprehensive treatment protocol in 2008. Instead of administering drugs to patients randomly with the two mainstay drugs, treatment is individualized; sensitivity testing is done to determine which antibiotics are effective against a resistant strain of TB, and then formulating an effective combination drug therapy. The regimen may include newer, second-line drugs that are generally not prescribed at first because of their high cost.

The researchers noted a downward trend in the percentage of multi-drug resistant TB infections in nine sample countries. Only in Russia did the researchers find an increase in the number of reported cases. But Dye says there's evidence that the WHO protocol to treat drug-resistant tuberculosis is beginning to work there, too.

DYE: "Russia should be able to turn around the epidemic [of MDR TB] just like other countries if only it does the right thing. And we're beginning to see very early signs that this is happening. But we need to watch this for a few more years to be sure."

BERMAN: Dye says more studies are needed in other countries, including India and China, to determine whether the downward trends in MDR-infection rates are more widespread.

The WHO's update on progress in treating multi-drug resistant tuberculosis is published this week in the journal Science Translational Medicine.



Science Students Do Better When Teachers Go Back To School

New research indicates that high school science teachers who get actual, hands-on experience doing scientific research become better teachers as measured by their students' test results.

The study looked at results from the Summer Research Program at Columbia University in New York.

Twenty years ago, Samuel Silverstein founded the program, to give experienced science teachers the chance to pick up skills that they might not have gotten when they were training to become teachers.

SILVERSTEIN: "Teachers get academic preparation, but they don't get much practical help in helping kids understand science, or themselves understanding the discipline of science."

In Silverstein's program, high school teachers are paired with university science professors and work on research projects.

In a paper published in the journal Science, Silverstein reports on the success of the program as measured by students' performance on a standardized test for college-bound students called the Regents Exam.

SILVERSTEIN: "Ten percent more kids in these teachers' classes are passing a New York state Regents Exam in science than [students of] other teachers in the same school. That's a very, very big difference, and it's highly statistically significant."

During their two summers in the program, the high school teachers may pick up useful knowledge or techniques, but Silverstein says he also sees evidence of a change in the way they think about scientific problems.

SILVERSTEIN: "Teachers tell us, when I go back to my school, I'm going to stop saying 'that's right' and 'that's wrong' to students and say 'why do you think that?' Because that's what you scientists do to me all the time when I'm in the lab. You're much more interested in why I think something than whether I know the right or the wrong answer."

The program is not cheap. It costs more than $27,000 per teacher, paid for by gifts and grants. But even if the high schools paid the costs directly, Silverstein says it would be a good investment.

SILVERSTEIN: "The cost of course repetition that is eliminated by these additional students, 10 percent more passing a Regent's exam, and the increased retention of teachers, because teachers who are in this program stay in teaching because they're succeeding ?? those two factors mean the [New York] city department of education is making $1.14 for every dollar our sponsors put into the program."

Samuel Silverstein's program at Columbia University is for science teachers, but he says it could be adapted to any other area of education.



Website of the Week Offers Food Safety Tips

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

We're lucky enough, here in the United States, to have some of the safest food in the world. But contamination sometimes occurs at food processing plants and consumers often overlook basic food preparation safety guidelines. At our Website of the Week, FoodSafety.gov, experts provide the latest information about safety-related food recalls and tips for keeping your family safe, all presented in a user-friendly way.

BACKUS: "It was really designed so that people could find the information they need and they didn't have to know the 'secret code' in order to find it. If you went on the site right now you could find out what the latest food recall was, but you could also find out how long you should store eggs in a refrigerator."

Jenny Backus is spokeswoman for the Department of Health and Human Services, one of several government agencies that have pooled their expertise to bring us FoodSafety.gov.

It's a practical site that includes information on topics like shopping and food preparation ?? such as how to buy produce to reduce the risk of food poisoning, and safe cooking techniques ?? that's a subject they have podcasts on. And if you think something you've eaten has made you sick, they've got that covered, too.

There's also advice on keeping your food safe during times of emergency.

BACKUS: "And that is such an important thing as so many places around the world face natural disasters every day and you never know when something will happen, and you want to have done everything you can to keep you and your family safe."


If you can't find the answer to your food safety problem, they have an 'ask the expert' feature, right on the site at FoodSafety.gov, or get the link to this and more than 250 other Websites of the Week from our site, VOAnews.com/ourworld.

MUSIC: Louis Armstrong ?? "Potato Head Blues"

You're listening to Our World, the weekly science and technology magazine from VOA News. I'm Art Chimes in Washington.



US Report Raises Biofuels Questions

From our food and agriculture desk this week ...

The U.S. Government Accountability Office, the GAO, is questioning the generous government subsidies some companies are receiving for producing maize-based ethanol for fuel. In a recent report, the GAO recommends that regulators look at the broader environmental impacts of raising crops for biofuels. VOA's Steve Baragona reports.

BARAGONA: In a bid to reduce dependence on foreign oil, Congress passed a law two years ago requiring U.S. motor fuels to include nearly 140 billion liters of ethanol or other biofuels by 2022, up from around 40 billion last year.

Demand for maize has grown as a result. That has been a boon for farmers but has raised costs for livestock feed and, to a lesser extent, food.

In a report out earlier this month, GAO says as the demand for biofuels continues to grow, air, water, and soil quality are likely to suffer, although the extent of the damage is unclear.

The report says a federal tax credit established in 1978 to help develop the ethanol industry is no longer needed because the industry has grown rapidly in the last few years. The GAO says the tax credit cost the U.S. Treasury $4 billion last year.

JONES: "We definitely have concerns about what they're saying."

BARAGONA: That's energy specialist Elizabeth Jones with the American Farm Bureau Federation. Speaking to the Farm Bureau's Newsline program, she said farm groups are concerned that more environmental regulations will hinder the industry's continued growth.

JONES: "We're also concerned about their suggestion [that] Congress consider changing or eliminating the ethanol tax credit. That's something we've supported and think is important as the industry grows."

BARAGONA: Jones says farmers who might be thinking of raising crops for biofuels need to be confident about the industry's future. She notes that President Obama supported biofuels development during his campaign for the White House last year and farm groups hope to work with his administration to help him keep that promise.

Steve Baragona, VOA news, Washington



Farmers Turn Waste Food Crop Into Biofuel

Many critics of corn-based ethanol say non-food plants should be used as a base for making biofuels. There are some technical problems to making that a reality, but another approach is using plants grown for food, but which for one reason or another are inedible.

Which brings us to our next story about one of our most popular and traditional summer foods here in America ?? watermelon.

Like most farm crops, not all the watermelons that are grown commercially are actually eaten. In fact, more than 300 million kilograms of watermelon rot away in U.S. farm fields every year. Those left behind can't be sold because they're sunburned, diseased, or damaged. What a waste! But now scientists in Oklahoma are working on a way to use this abandoned fruit. Gail Banzet reports.


BANZET: Growers say it was a pretty fair season for watermelons in 2009. A lot of ripe, juicy melons were enjoyed during the summer months, but, every year, 20 percent of the crop never even makes it to buyers.

Research chemist Wayne Fish steers his truck around the USDA's agriculture research laboratory in Lane, Oklahoma.

FISH: "This is what gets plowed back into the fields, so to speak. We are here."

There are 320 acres [130 hectares] of different crops and vegetables here, and one acre [0.4 hectares] is dedicated to watermelons. Workers have already picked the good ones. And those that are left are discolored, misshapen, or damaged by raccoons or birds. But Wayne Fish says that watermelon can still be used.

FISH: "It'll still make ethanol fine."

BANZET: Four years ago, the National Watermelon Association started studying the ethanol potential of watermelon sugars. When the project showed favorable results, a trial process began at the research station in Oklahoma. Bob Morrissey is Executive Director of the National Watermelon Association.

MORRISSEY: "If you've got that fully developed watermelon there, it has all of the components ?? the water, the sugar, and the fiber ?? to create ethanol."

BANZET: Back at the research station in a lab, Wayne Fish and his team combine yeast with THE watermelon sugars. Hours later, the mixture is fermented and placed in a still.

FISH: "By distilling that mixture, one drives the ethanol off together with a small amount of water. That's how we enrich the mixture to ultimately 95 percent ethanol."

BANZET: Fish says the project is not an attempt to replace sugar cane or corn for ethanol. This pilot phase of testing shows wasted watermelons can simply add some ethanol to the overall market.

Bob Morrissey at the National Watermelon Association says using the melons could open up a whole new market for farmers. They could sell the good ones to people and the bad ones to ethanol plants.

MORRISSEY: "That farmer could literally harvest his or her entire crop, send it to the ethanol plant, and at least get something out of it to try and cover their cost instead of taking a complete loss."

There are a lot of growers across the country who are worried about wasting melons.

Jim Motes is from Oklahoma. And even though he's not a huge farmer, he says he's always looking for ways to make the most of his crop.

MOTES: "If they can find a large enough quantity to make it efficient, then it's a good idea, because there are a lot of watermelons laying there when the field disked up that ought to find some use."

Researchers say watermelon ethanol is drawing a lot of attention. A Texas-based company called Common Sense Agriculture is currently working on a mobile unit that would process the melon sugars and produce ethanol right there in the field.

For The Environment Report, I'm Gail Banzet.

Support for the Environment Report on VOA comes from the Joyce Foundation and the Great Lakes Fishery Trust. You can find more stories and post your comments at EnvironmentReport.org.



And finally today ...

Researchers at the University of California, Los Angeles, found positive changes in mental functioning from using the Internet to search the Web.

Adults 55 and older who had very little online experience began to practice doing Web searches at home. Functional MRI scans showed that after just two weeks they were triggering areas of the brain known to be important for memory and decision-making, similar to experienced Internet users.

Principal author Teena Moody says the study suggests that online searching may be be a simple way of improving mental skills in older adults.

Wasting time on the Internet? No, honey, I'm doing brain exercises!



MUSIC: "Our World" theme

That's our show for this week. We'd like to hear from you. Please email us at ourworld@voanews.com. Or write us at -

Our World
Voice of America
Washington, DC 20237 USA

Our program was 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.


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