MUSIC: "Our World" theme

This week on "Our World" ... A better way to share the bounty of the world's oceans ... the little robots that could ... and tackling the challenge of feeding the poor in Africa ...

PARR:  "If you could export U.S. levels of yield, you could double production in East Africa, and you could have almost a five-fold increase in sub-Saharan Africa."

Those stories, a hopeful new approach to depression, and more. I'm Art Chimes. Welcome to VOA's science and technology magazine, "Our World."


New way of sharing the catch might save world fisheries

With many of the world's fisheries in serious decline, a new approach to apportioning the catch might be just the thing to prevent further collapse of fish populations and to replenish this important food resource. As VOA's Jessica Berman reports, a multidisciplinary team of scientists in California says a system called "catch shares" could alter the future of global fishing.

BERMAN:  The world's fisheries are in serious trouble. Experts say one-fourth of them have collapsed as a result of over-fishing. At the current rate, a study published in Science two years ago predicted that the entire industry would go the same way by the middle of the century.

To protect fisheries, countries and communities have established catch quotas where fishermen compete for stocks.

Christopher Costello, an economics professor at the University of California Santa Barbara, says this results in a race to fish, where independent fisherman buy bigger boats and larger nets, all in an effort to outdo the competition.

But Costello says a plan called "catch shares" could turn the endangered fishing industry around.  

Under the plan, a community or co-op would give each licensed fisherman a percentage of the catch.

COSTELLO:  "So you as a fisherman know exactly how many fish you are allowed to harvest during that season. Nobody can take those fish away from you. No matter how fast I go out and fish, you can fish as slowly and efficiently as you want to in order to harvest that total catch that you are allowed to."

BERMAN:  Costello and colleagues at the University of California and the University of Hawaii studied data on 11,000 commercial fisheries around the world between 1950 and 2003.

In a study published in Science, researchers found the collapse rate was cut in half among 121 fisheries that were managed by catch share systems compared to traditional commercial fisheries.

John Lynham is an economics professor at the University of Hawaii.

LYNHAM:  "The point of this paper is not that catch shares are the panacea to the fisheries crisis; but that systems where fisherman have a financial incentive to care about the long run health of systems can prevent the crisis."

BERMAN:  Some environmental groups have been critical of catch share strategies because they believe the plan privatizes a public resource.

But scientists say the evidence shows less pressure on commercial fisheries as a result of catch shares both saves and revives fisheries.

This week, the European Union announced a full review and plans to overhaul its fishing policies that it says depletes fish stocks and penalizes commercial fisheries that play by the rules. Jessica Berman, VOA News, Washington.


Study shows long-lasting impact of Rwanda genocide

One of the most devastating events of the past quarter century was the 1994 genocide in Rwanda. At least 800,000 people were killed in the tribal bloodletting, and many who survived the carnage were children who had lost many family members, and frequently one or both parents. As we hear from reporter Rose Hoban, mental health experts have been assessing the psychological damage suffered by those survivors, and studying ways to help them heal their still-painful wounds:

HOBAN:  Child psychologist Neil Boris from Tulane University in New Orleans says almost every family in Rwanda was affected by the genocide.

BORIS:  "Behind that came the HIV epidemic, so really it's kind of a one-two punch. Rwanda has the highest proportion of what we call double orphans that is, young people who have lost both parents of any country where we feel like we have reasonable data. And that's because it's not just HIV, but it's HIV on top of the genocide."  

HOBAN:  Many of these young people were left to head households filled with younger siblings and relatives. And these young people frequently have no adults who they can turn to for advice and guidance. Boris says it's a situation that has left many of them emotionally scarred.

Boris partnered with the aid organization World Vision and the Rwandan School of Public Health to study about 700 of these young family leaders. Many of then were about 10 years old when the genocide occurred. 

Boris says they found about half of them suffered from depression.

BORIS:  "The second thing we found was that taking care of others in the home meant the young people themselves couldn't pursue school, and only about seven percent of them had even gotten to secondary school in their lives. The third thing we found out was that their perceived degree of marginalization from the community and from friends, was strongly associated with depressive symptoms."

HOBAN:  Boris and his colleagues also found that many of these family groups didn't have enough food to eat. That affected their physical health, and contributed to the caregivers' depression.

After studying the data, the researchers suggested some ways to help these young households.

BORIS:  "By getting adult community volunteers to reach out and mentor youth heads of household caring for other kids, we've shown that that alone improves depression over time, improves degree of social isolation over time, and really helped these young people as time went on."

HOBAN:  Boris is currently working on more ways to help these young heads of household. He says he believes that with time and assistance, the young people of Rwanda can get beyond the tragedy of the genocide and help their society recover.

His paper is published in the Archives of Pediatric and Adolescent Medicine. I'm Rose Hoban.


New investment urged to stimilate African agriculture

If genocide orphans in Rwanda have trouble feeding their families, they're not the only ones.

Food insecurity is a chronic problem across much of Africa.

At the annual National Food Policy Conference in Washington this month, experts urged major new investments to stimulate agricultural development on the continent. Véronique LaCapra reports.

KARANJA:  "Three quarters of the world's ultra poor these are people living on less than 50 cents a day live in Africa."

LaCAPRA:  Daniel Karanja, a senior fellow at the Partnership to Cut Hunger and Poverty in Africa, says that about a third of Africa's seven million people are undernourished. He attributes Africa's food insecurity to a combination of increasing population growth and declining agricultural production.

KARANJA:  "This has been going on for a while, the last 30 years, resulting in a structural food deficit, as food demand outstrips domestic food supply. Most African countries back in the 70s were net exporters, now most of them are net importers of food."

LaCAPRA:  Karanja blames environmental degradation for much of the decline in agricultural productivity.

KARANJA:  Most smallholder farmers have been cultivating their farms for five to six decades without fallow [idle seasons], mining every bit of nutrients and adding very little back."

LaCAPRA:  And Karanja predicts that climate change will exacerbate the problem.

KARANJA:  "There is great reliance on rainfall. And that has become increasingly unpredictable, erratic, and unreliable."

LaCAPRA:  The key to improving food security in Africa, says Karanja, is to invest in agriculture.

KARANJA:  "Three out of every four Africans live in rural areas and depend entirely on agriculture for their livelihood.  The most viable means of improving the livelihood of poor people and achieving rapid poverty and hunger reduction in Africa is through investments that accelerate agricultural growth."

PARR:  "We think that increasing agricultural yields is at the heart of agricultural sustainability."

LaCAPRA:  Michael Parr is a senior manager at the chemical company Dupont, a founding member of an industry coalition called the Alliance for Abundant Food & Energy.

PARR:  "If you could export U.S. levels of yield to other parts of the world, you could double production in East Africa, you could triple production in South Asia, and you could have almost a five-fold increase in sub-Saharan Africa."

LaCAPRA:  U.S. farmers have achieved their remarkable yields largely through the use of improved seeds, fertilizers, and pesticides.

According to Siwa Msangi, a Research Fellow at the International Food Policy Research Institute, achieving such big yield gains in Africa will require some fundamental changes in the way farmers grow food.

Msangi says that well-managed irrigation projects and giving smallholder farmers access to improved seeds would help maintain yields as climate change makes rainfall less reliable.

MSANGI:  "That's where you need the improved drought-tolerance, heat-tolerance, salt-tolerant technologies, both from non-transgenic breeding and transgenic breeding, and I think an evidence-based approach to judging these technologies equipping the countries themselves to evaluate the suitability of those technologies for their own systems, and to adopt them."

LaCAPRA:  But for any of these new technologies to be successful, says rural sociologist Mary Hendrickson, they will need to be carefully integrated into existing farming systems.

HENDRICKSON:  "We've really got to talk about appropriate and complementary integration of technology, of local and traditional knowledge systems, and indigenous knowledge, with what we learn through formal agriculture knowledge, science and technology."

LaCAPRA:  Daniel Karanja agrees.

KARANJA:  "We have to make sure that one, it's appropriate, two, decisions are made locally, and number three, that there's capacity to manage those kinds of technologies."

LaCAPRA:  For agricultural development to actually benefit the poor, says Mary Hendrickson, it must create opportunities for innovation and entrepreneurship that specifically help small farmers. But Hendrickson adds that farmers will need to balance their increased production against potential environmental impacts. For Our World, I'm Véronique LaCapra.


The latest slang on our Website of the Week

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

This week, it's a resource for people who want to know more about the English language in all its contemporary messiness a great place to learn about the words you won't find in most regular dictionaries.

PECKHAM:  "Urban Dictionary is a slang dictionary with definitions written by people who come to visit the site. So all of its content is written by normal people like you and me."

Aaron Peckham is the founder of, a site he created as a university student.

Anyone can submit a new word, or a new definition for a word already in the dictionary. Peckham and his team of editors add about 1,000 new entries every day.

The result is an English lexicon that is fun, engaging, and up-to-date, if not exactly scholarly. It is, we should warn you, full of words you can't say on the radio. But of course, those might just be the words you need to know about.

PECKHAM:  "People have written in to me to tell me that they use Urban Dictionary to figure out what their kids are talking about, what their students are talking about, to figure out what people are talking about at the MTV music awards. Even what politicians say sometimes can be decoded with Urban"

Because it's written by ordinary, mostly young users, not stuffy old editors of mainstream lexicons, is a window on not just the English language but on contemporary culture.

PECKHAM:  "I hope Urban Dictionary is a way to figure out what's going on in American culture. Some people have told me that after arriving in the United States that Urban Dictionary's been a really valuable resource to figure out what people are really saying because there's so much meaning behind words besides what's in the normal dictionary definition. And Urban Dictionary can help to decode that."

 ... Especially since every definition includes an example of contemporary usage at, or get the link to this and more than 200 other Websites of the Week from our site,


MUSIC:  Cafe Soul All-Stars "Urban Jungle"


Mo' better radio on VOA's science and technology magazine, Our World. I'm Art Chimes in Washington. 


Specialized little robots take a cue from nature

You'll find the term "nano" in the Urban Dictionary, which brings us to our next story from the NanoRobotics lab at Carnegie Mellon University.

That's where a team of young inventors is taking inspiration from the natural world as they develop specialized little robots.

VOA's Rosanne Skirble has our story.

SKIRBLE:  In the university's NanoRobotics Lab mechanical engineering graduate student Mike Murphy takes his cue from nature.

MURPHY:  "So you see the lights flashing, and I'll go to my computer and just [hit] some keys to remotely control the robot...."

SKIRBLE:  Murphy's guide is the gecko, a tropical lizard with sticky feet. He says it's the millions of microscopic hairs on the gecko's footpads, which actually connect with the molecular bonds of the surface material, that give the lizard its remarkable climbing ability.

MURPHY:  "By studying these animals we can create synthetic versions of their adhesives and put them on robots."

SKIRBLE:  The tri-legged climbing Waalbot fits into the palm of Murphy's hand. Its microscopic polymer foot hairs give it some of the gecko's climbing power, although Murphy, who has positioned a crash pad for the robot's fall, says his version is on a steep learning curve.

MURPHY:  "We have shown the ability to adhere to smooth surfaces at the same level as a gecko can. But we are also working on creating structures that can attach to slightly rougher surfaces. And also, another very large challenge is keeping our adhesive pads clean. Our adhesive pads will pick up contaminants from the climbing surfaces, but the animals [geckos] don't have this problem."

SKIRBLE:  The Waalbot is designed to carry a payload, which Murphy says could be a camera or a mobile relay network for a computer system.

MURPHY:  "You can imagine some surveillance or inspection type of applications where you have, maybe, a robot climbing on the surface of a building, maybe through the ducts of a building and doing inspection, looking for damage that might need to be repaired. Even on the outside of a space shuttle where there really aren't any conventional adhesives that are useful, you can have a robot that climbs around and looks for damage, and maybe he can even repair it."

SKIRBLE:  Murphy's Waalbot shares lab space with Water Runner. The robot is modeled after the speedy basilisk lizard, which walks on water at speeds of 1.5 meters per second in the rain forests of Central and South America. Graduate student Steven Floyd says the basilisk stays afloat in the way it slaps and strokes the water.

FLOYD:  "Some of the idea that went behind it was that the basilisk lizard can run on water and it can run on land and it uses similar motions for both, so the idea being, can we create an amphibious robot that doesn't actually swim. It just kind of runs all the time and can also do walking over surfaces."

SKIRBLE:  Floyd says while Water Runner could make a great toy, its ability to operate on land and water broadens its use.

FLOYD:  "Looking at partially flooded environments where if you have any sort of marsh land, where sometimes you have land, sometimes you have water, you can't also gauge the depth of that water. So any robot that's geared for land might get stuck or submerged. Any robot that's geared for water might get trapped because there is land. But something that could do both could do it. So semi-flooded environments, I think, is a really good application for this particular robot."

OZCAN:  "We turn on the electronic board using this switch, on-off switch here...."

SKIRBLE:  Graduate student Onur Ozcan from Turkey works nearby on Water Strider. The robotic prototype is fashioned after the pond skimmer, an insect that can glide over water with little drag or friction.

OZCAN:  "If we can mimic this behavior with really this tiny robot then it's really a very big success for us. We can use it to measure the quality of water on dams or on any water source."

SKIRBLE:  As Carnegie Mellon University graduate students Onur Ozcan, Steven Floyd, and Mike Murphy sort through mechanical problems in the NanoRobotics Lab, they continue to marvel at the beauty of the natural world and the creatures that inhabit it. Onur Ozcan sums up their experience.

OZCAN:  "Before working on this project, I mean they were just like insects, you don't see how amazing they are. I mean, after working on these projects you begin to realize that their mechanical working principles are really, really amazing. It really changes your view about insects."

SKIRBLE:  Lessons from nature in the NanoRobotics Lab at Carnegie Mellon University in Pittsburgh, Pennsylvania. I'm Rosanne Skirble.


New hope for hope as a treatment for depression

Finally today, a new weapon in the fight against depression. A study presented recently at the American Psychological Association's annual meeting indicates hope can be an effective therapy. Erika Celeste reports.

LONG:  "A lot of the people, they come in and they're grumpy and dissatisfied and they just want the magic answer to be able to read again. We can't give that to them, but we do have some solutions."

Kristin Long volunteers at a low vision center, working primarily with older adults who are losing or have lo