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14 August 2009
MUSIC: "Our World" theme
This week on Our World: Unearthing a prehistoric tool-making technique in Africa ... a new way of delivering anti-cancer drugs ... and a reality check on NASA's budget for going back to the Moon ...
AUGUSTINE: "I think it would be fair to say that our view is that it would be difficult with the current budget to do anything that's terribly inspiring in the human space flight area."
Those stories, who decides how farm animals get treated, and more.
I'm Art Chimes. Welcome to VOA's science and technology magazine, "Our World."
Early Africans heat-treated rock to make better tools
Scientists working at an archaeological site in South Africa say they have evidence that people living there 70,000 years ago used fire to heat up rocks so they would make better stone tools.
The international team of researchers published their findings this week in the journal Science. The work by lead author Kyle Brown, an American doctoral student at the University of Cape Town in South Africa, rewrites the history book for the use of fire as an engineering tool.
BROWN: "Generally people have accepted, archaeologists accept that heat treatment began around 25,000 years ago in Europe. So we're pushing this back 30-40,000 years and putting it in Southern Africa rather than in Europe."
Q: That's a big change.
BROWN: "It is a big change."
Brown calls himself an experimental archaeologist. So to find out how ancient people made stone tools, he tried to make stone tools like the ones he was finding. But they weren't coming out right.
BROWN: "We spent a lot of time looking for [stones we could work to replicate the ancient tools] in field surveys, and we couldn't find anything that looked like what we were seeing."
The researchers knew that ancient tool makers had heated up stone before working it into tools, though not remotely as long ago as 70,000 years, the age of the site where they were working.
BROWN: "So it was kind of almost out of desperation that we decided to try this because we knew that in recent times people were doing it, and lo-and-behold, it worked."
What worked was a controlled heating and cooling of the stone that was a lot more sophisticated than just sticking some rocks in a fire. First, says Brown, you have to get the fire hot enough.
BROWN: "To get a temperature of about 350 degrees Celsius beneath that fire, you actually have to have quite a large fire, or at least use a lot of hardwood fuel."
And you don't just drop the rocks into the flames. To even out the temperature, he buried the stone under the fire, beneath a layer of sand. And like any kind of cooking, timing is critical.
BROWN: "So this fire, you build it up, slowly over time, about 12 hours, you have to wait about, you know, five hours for it to do its thing underneath the fire, and then however long it takes to cool back down to the ambient temperature outside. So this whole process can take 20 to 40 hours to do."
The ability to figure out how to heat-treat stone to make a better tool shows a level of sophistication that Brown says demands a reassessment of people we might otherwise dismiss as primitive savages.
BROWN: "These aren't the kind of cavemen that you see in cartoons. They were able to have these big genius moments, where they could connect seemingly unrelated events and put them together. Somebody discovers, 'Aha!, I've got this tool that I accidentally burned in the fire, pulled it out and flaked it, I can do this again.' So yeah, these are pretty sophisticated people we're talking about."
And what were these stone tools used for? Kyle Brown of the University of Cape Town says killing or butchering game for sure; they know that from marks on the animal bones they found near the tools, and probably also for woodworking.
For an extended version of my conversation with Kyle Brown, you need a 21st century tool, a computer, to check out our website, voanews.com/ourworld.
Macho men skip routine medical exams
I don't know macho those cavemen were, but some new research indicates that men who think that being a man means being strong and tough are more likely to skip life-saving health exams. Faith Lapidus reports.
LAPIDUS: Although men typically earn more money than women, giving them access to better health services, they don't necessarily live longer, healthier lives.
Sociologist Kristen Springer wondered how men's concept of masculinity impacts their health care decisions.
SPRINGER: "We had asked men how strongly they agree with statements such as 'when a man is feeling pain he should not let it show.' Men with these strong masculinity ideals were 50 percent less likely to get all of these preventive services."
LAPIDUS: The Rutgers University professor stresses that the annual medical services she asked participants about - prostate exams, general physical exams, and flu shots - are especially important for men as they get older.
SPRINGER: "Preventive care is critically important for mid life and upper age men because [American] men die five years earlier than women do and they're less likely to get these preventive health care services that they need. So it's one of the most important factors for these men to stay healthy and to live longer."
LAPIDUS: While acknowledging that the sample group of men from the Midwestern state of Wisconsin lacks diversity, Springer thinks her findings are still applicable to other cultures.
SPRINGER: "The Wisconsin longitudinal study is primarily white. These are men who are 65 years old. They were from Wisconsin. So it certainly has its limitations in that sense. In terms of broader generalizability, based on the literature I would expect that these results should hold in other contexts, so long as this idea of masculinity is being invulnerable and not showing weakness, and going to the doctor is a sign of weakness."
LAPIDUS: Springer says this 'macho' vision of how tough a man should be needs to be changed.
SPRINGER: "To the degree that we can undermine the ideas of masculinity as strong and invulnerable, we can help get men to go to the doctor and be healthier."
LAPIDUS: Springer presented her study at the annual meeting of the American Sociological Society in San Francisco.
Faith Lapidus, VOA News, Washington.
MUSIC: Village People - "Macho Man"
Doctors use nanotech to aim bee venom at tumors
Of course, one reason medical checkups are important is that it's often more effective to treat a disease if you start early. That's especially true for many cancers.
Now, scientists have found a way to deploy the poison in bee venom against cancerous tumors, using tiny delivery vehicles called nanobees. Meredith Hegg reports.
HEGG: The challenge posed by many potentially effective anti-cancer drugs is how to use these deadly compounds to fight disease without harming the rest of the body. Dr. Sam Wickline may have found one solution. He develops minute nanoparticles that carry medicine to the spot where it's needed.
WICKLINE: "In this case we've taken a fairly toxic material which is a component of regular old bee venom - it's called melittin - and we've put that on our carrier and, lo and behold, it seems to get to the right place, do its job to treat cancers of several types, and then not cause trouble elsewhere."
HEGG: Dr. Wickline and his colleagues at Washington University in Saint Louis tested their creations, affectionately named nanobees, on breast cancer tumors, melanoma tumors, and precancerous lesions in mice.
WICKLINE: "They were extremely effective in all of those types of tumors given the kinds of dosages, modest dosages that we used. And in fact, in melanoma tumors, they basically prevented them from growing, and in precancerous lesions in the skin, they prevented that, at least in the short term, from turning into a cancer."
HEGG: Wickline says the nanobees are able to target the disease thanks, in part, to the unusual leakiness of the blood vessels that surround tumors.
WICKLINE: "Now, the ones that get to the tumor can either get trapped in these leaky vessels or, we've put a homing system on them so that they know where the tumor is because the blood vessels around the tumor that supply it with oxygen and nutrients, express a kind of a code that's not found on most normal tissues in your body."
HEGG: Wickline hopes to have human clinical trials underway in about two years. He predicts the federal drug approval process will likely be more drawn out because of the number of components involved in this kind of treatment.
Wickline's research on cancer fighting nanobees is published in the Journal of Clinical Investigation. I'm Meredith Hegg.
Researchers Deliver Strategy to Double Nigeria's Maize Crop
Of course, it's better to stay healthy, and many experts say we should eat more fruits and vegetables. In some regions of the world, that can be a challenge -- especially so in parts of Africa, where chronically poor crop yields have put a crimp not only in people's diets but also in farmers' incomes. Now, crop scientists in Nigeria have proposed ways to help that country double its maize production.
Our food and agriculture reporter Steve Baragona has more.
BARAGONA: In 2006, the Nigerian government launched an ambitious campaign to double the nation's maize harvest, not only to bolster food and feed supplies, but also to strengthen Nigeria's ability to provide emergency food aid to its African neighbors.
The agriculture ministry asked national research institutions, non-governmental organizations, and the International Institute for Tropical Agriculture, or IITA, to come up with ways to boost maize yields.
Researchers found that most farmers were using lower-yielding seeds. One reason, according to the IITA's Sam Oyewole Ajala was that Nigeria's seed companies weren't selling better ones.
AJALA: "Although Nigeria is about the only country in the South region that has developed seed companies, the seeds were really not getting to those farmers."
BARAGONA: So, Ajala says, it was easy for researchers to see how yields might be improved.
AJALA: "It was quite simple. We were just making sure that the best variety goes to the best place. And making sure that seed companies are able to sell varieties that are very good enough."
BARAGONA: Researchers helped seed companies develop and deliver better seeds. They educated farmers about the seeds. And they encouraged farmers to use labor-saving tools.
Because of these and other strategies, farmers were able to nearly triple yields on more than 1,000 test farms across the country. Yields went from 1.5 tons per hectare in 2006 to 4.2 tons in the latest harvest.
Ajala submitted a proposal to the Nigerian government to put the program in action across the country. But he notes that Nigeria's farmer education and research and development programs are weak and there are not many skilled workers to staff them.
AJALA: "Those are issues on the ground. They are challenges. They are real challenges."
BARAGONA: But Ajala sees the Nigerian government's commitment to doubling the country's maize yield as a promising sign, and he believes that in time, the goal can be reached.
Steve Baragona, VOA News, Washington.
Website of the Week features sounds of New Orleans
It's time again for our Website of the Week, when we showcase interesting and innovative online destinations.
One of America's most distinctive cities is New Orleans. White, black, and French cultures meet in the port near the mouth of the Mississippi River, seasoned by great food and enlivened by fabulous music. New Orleans was battered by hurricane Katrina in 2005, bringing new attention to the city's rich cultural heritage.
The creators of our Website of the Week are collecting the sounds of New Orleans, which you can hear by clicking on a map that shows where they were recorded.
BRANCASI: "Open Sound New Orleans is a community media project that invites and enables New Orlineans to document their lives in sound. New Orlineans participate by recording or making recording requests for the important sounds and voices in their lives and adding them to the sound map."
Jacob Brancasi is co-director of OpenSoundNewOrleans.com, which features the city's people, music, and ambient sounds -- the soundtrack of New Orleans.
Those are some cicadas recorded by Jeffrey and Ruby Haupt. They're professional audio people, but Open Sound New Orleans' other co-director, Heather Booth, says part of the project also includes training people in recording skills and lending them the equipment to document their city.
BOOTH: "The contributors really range from individuals we've never laid eyes on, who just upload recordings of work and family and really personal things, to more cohesive groups that we work intensively with, like the new immigrants to New Orleans, who really wanted an opportunity to open a dialogue with New Orlineans about who they are and why they're here in New Orleans."
Experience the rich soundscape of New Orleans at OpenSoundNewOrleans.com, or get the link to this and more than 250 other Websites of the Week from our site, VOAnews.com/ourworld.
MUSIC: Baby Boy'z
One more sound from the site: the youthful band Baby Boy'z as recorded by "Rick in Gentilly." It's Our World, the weekly science and technology magazine from VOA News. I'm Art Chimes in Washington.
Experts say NASA budget too small for big space plans
An expert panel advising NASA and the Obama administration on the future of human space flight has concluded that going to Mars, or even returning to the Moon, is too expensive under the current budget.
The panel, including professors, former astronauts, and experts from the aerospace industry, has been holding a series of meetings, hearing from Americans about what they want their country to do in space. At their final public meeting, here in Washington on Wednesday, the group had a different agenda.
AUGUSTINE: "Today, our principal purpose is going to be to finalize the options that we presented when we last met a week ago and also to do an evaluation of them...."
Committee chairman Norman Augustine, former CEO of NASA contractor Lockheed Martin, opened the six-hour meeting, which ended up slashing the number of options under consideration from about a dozen to just four basic plans.
The committee was charged with developing human space flight options within current budget guidelines, but former astronaut Sally Ride presented detailed scenarios on the costs of the various options and concluded none of the options would fly, given the financial limitations they had to work with.
RIDE: "I think the points here are fairly obvious: exploration really doesn't look viable under the [fiscal year 2010] budget guidance. Some things are more expensive than others. Deep Space appears to be the most cost-effective of the exploration scenarios, and it has earlier return also."
The Deep Space scenario she mentioned learning to work in space, including flybys of the Moon, Mars, or nearby asteroids, and possibly landing on the Moon two decades from now.
The committee also considered NASA's current roadmap - retiring the space shuttle next year, and using Russian spacecraft to get to the International Space Station until NASA's new Ares 1 rocket and Orion crew capsule are developed.
But the panel said that with the current budget, the new rocket and capsule wouldn't be ready until after the space station was shut down and crashed into the ocean - "deorbited" in NASA-speak - in 2016.
NASA's current Constellation program includes a bigger rocket, Ares 5, which would be capable of taking humans to the Moon after 2021. But the Augustine committee calculates the rocket won't be ready until 2028, given the present budget.
If NASA's current program is beyond its budget, Norman Augustine said more ambitious programs are equally out of reach.
AUGUSTINE: "I think it would be fair to say that our view is that it would be difficult with the current budget to do anything that's terribly inspiring in the human space flight area. On the other hand, there are important things one can do to prepare for human space flight and for important achievements, it's just that they won't come as soon."
Human space flight is expensive, no question about it. The space station may end up costing around $100 billion dollars. Even dropping it in the ocean may cost a billion and a half.
The Augustine committee is due to submit its final report to NASA and the White House in a couple of weeks.
Farm interests, activists battle over treatment of livestock
Finally today ... Farms and ranches that keep lots of animals, such as chicken or cattle, are subject to laws that regulate how the animals are kept. Many people object to conditions on what they call factory farms. As Julie Grant reports, advocates on both sides of the issue say they are concerned about the animals' welfare.
GRANT: The Humane Society of the United States says it's shameful the way animals are treated on many American farms. Paul Shapiro says veal calves, pregnant pigs, and egg-laying hens are all kept in cages so small - it's cruel.
SHAPIRO: "Hundreds of millions of egg-laying hens in the nation are confined in tiny battery cages that are so restrictive the birds are unable even to spread their wings."
GRANT: Shapiro says some farms house millions of hens, all squished into tiny cages, and none of them get the chance to nest, or act in any way like natural chickens. The Humane Society has spent millions of dollars pushing for change in California and other states.
But when the Humane Society hit Ohio with its campaign, the state Farm Bureau Federation pushed back.
Keith Stimpert is spokesman for the Ohio Farm Bureau. He says there's a reason cages are a certain size for hens, calves, and pigs: the animals' safety.
STIMPERT: "You can expand space, but you're going to increase aspects of fighting or cannibalistic behavior, or the chance for that sow to fall down while she's pregnant."
GRANT: Stimpert says the Humane Society doesn't understand livestock.
So instead of negotiating with the Humane Society, the Ohio Farm Bureau is proposing something new: a state board to oversee the care of livestock.
GRANT: The board would include family farmers, veterinarians, a food safety expert, and a member of a local chapter of the Humane Society, among others.
But the Humane Society's Paul Shapiro says the board will be stacked by the Farm Bureau. He calls it a power grab by big agriculture.
SHAPIRO: "These are people who have opposed, tooth and nail, any form of agricultural regulation for years, and now, all of a sudden, in just a few weeks, they've gotten religion and feel grave urgency to enshrine in the state' s constitution their own favored system of oversight."
GRANT: Shapiro says this board will only protect the status quo. And that's not good for the animals.
Egg producer Mark Whipple runs a small farm in Clinton, Ohio. He's got about 1,500 hens. He says his hens are free range.
WHIPPLE: "There ain't no cages, really. They go in the box, lay their egg, and go out and run around with the rest of 'em, go eat, drink, and, I don't know, just be free."
GRANT: Whipple says he was never inclined to cage the hens.
You might expect him to side with the Humane Society on this debate. But he doesn't trust them to make decisions for farmers.
WHIPPLE: "I don't know that they really know where their food comes from - other than they go to the grocery store or they go to the refrigerator. Unfortunately, that's a lot the mentality of the world right now, so far removed from the farm at all, knowing about livestock."
GRANT: Whipple says there are good producers and bad producers out there - just like any business. He would rather see a board like the one proposed by the farm bureau than a mandate on cage sizes from a Washington, D.C.-based lobbying group.
But the Humane Society says the board proposed by the Farm Bureau won't make things better. If it's approved by voters this November, the Society plans to place its own initiative on animal treatment on the ballot next year.
Meanwhile, other farm states are considering the Ohio Farm Bureau's approach and might soon have their own advisory boards on how to treat animals.
For The Environment Report, I'm Julie Grant.
Support for the Environment Report comes from the Joyce Foundation, and the U.S. Department of Agriculture. You can hear the Report - and subscribe to the daily podcast at EnvironmentReport.org.
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Our World is edited by Rob Sivak. Felicia Butler is the technical director. Meredith Hegg researched and wrote our story on nanobees.
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