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Our World — 28 February 2009


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This week on Our World: A new space telescope to search for distant planets ... African innovation online ... and rethinking who's at risk for stroke:

CLAIBORNE JOHNSTON: "The perception has been that stroke is a disease of high income countries of the developed world, and our study suggests that the opposite should be the case."

Those stories, heart attacks: they're not just for men anymore, a new book about the human animal, and more.

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





UN scientists report faster ice melting in Antarctica, Greenland

A new report on climate change says ice is melting in Antarctica and around the North Pole faster than expected. In a separate study, scientists for the U.N. Intergovernmental Panel on Climate Change, the IPCC, report rapidly increasing carbon dioxide emissions and rapidly shrinking Arctic ice. VOA's Julia Ritchey wrote our report, which is read by Ruth Reader.

READER: The chairman of the IPCC, R.K. Pachauri, said 11 of the last 12 years were among the warmest for global surface temperature in recorded history. Pachauri testified before the U.S. Senate Committee on Environment and Public Works on the IPCC's latest findings on global warming.

He said climate change will impact some parts of the world more severely than others.

PACHAURI: "In Africa, for instance, by 2020 our projections show that 75 to 250 million people would be affected by water stress on account of climate change, and crop revenues could drop very rapidly. So we are really causing major distortions and disparities in economic development and growth throughout the world."

READER: Pachauri's testimony coincided with another study by the U.N.-backed International Polar Year program, which found that icecaps at both the North and South Poles are melting at unprecedented rate. The report, compiled by scientists from more than 60 countries, also says that the shrinking of polar and Greenland ice is fueling a rise in sea levels and the potential for dramatic changes in the global climate system.

The authors say that Arctic permafrost also reveals larger amounts of carbon than expected that, with further melting, could release more greenhouse gasses into the atmosphere.

Christopher Field, a contributor to the IPCC report, told the Senate committee that temperatures at the South Pole are rising faster than expected.

FIELD: "And just within the last few months we've seen confirmation that the continent of Antarctica has been warming. And it's been warming at a rate of almost 0.2 Fahrenheit [0.1 degree Celsius] per decade, comparable in pace to much of the rest of the Southern Hemisphere."

READER: Pachauri and Field say the costs of mitigating human generated carbon dioxide, or CO2, emissions are modest compared to the costs of doing nothing. Field says the U.N.'s Intergovernmental Panel on Climate Change says if CO2 levels are left unchecked, the earth's temperature could rise several degrees by the end of the century.

Scientists who are skeptical of the severity of global warming contend that global warming may be part of natural climate cycles that humans can do little about.



NASA's global warming satellite fails to reach orbit

For global warming, as for so many other things, scientists depend on satellites to keep an eye on the big picture and get measurements from the entire planet, not just where earth-based sensors can be located. Which is why the climate research community was disappointed this week when a U.S. science satellite to measure greenhouse gas emissions failed to reach orbit and crashed into the ocean near Antarctica shortly after launch on Tuesday.

The Orbiting Carbon Observatory, as we told you last week, was designed to help scientists better understand the carbon cycle, by pinpointing sources of carbon dioxide and also identifying where CO2 is stored, places known as carbon sinks.

The loss of the satellite is a setback, of course, but NASA scientist Michael Freilich says it's a setback that's hard to quantify. Japan last month launched its own CO2-sensing satellite, and scientific instruments on other satellites also help follow the carbon dioxide trail.

FREILICH: "So the science is advancing. Our understanding is moving forward. And it is difficult at this time to put a precise time delay, if you will, on how quickly in the future we'll be able to realize the understanding that OCO would have given us had it succeeded."

Officials say the $280 million mission failed when a nose cone-like part that protects the satellite during launch failed to come off when it was supposed to. As a result, the rocket was too heavy and failed to reach its intended orbit.



New space telescope will seek distant, Earth-like planets

In other space news: different rocket, different satellite. On Friday, NASA is set to launch its newest space telescope.

Unlike the general purpose Hubble Space Telescope, the Kepler mission has one goal - to find Earth-like planets elsewhere in our galaxy.

Kepler's telescope will stay pointed at an area of the sky with a concentration of some 100,000 stars that are considered likely candidates to have planets like ours.

Scientists won't be able to see the any planets directly. Instead, Kepler Project Manager Jim Fanson says they'll look for a slight dimming of stars as planets pass in front of them.

FRANSON: "We have to be able to measure the brightness change of stars down at the 20 part per million level. It's akin to measuring a flea as it creeps across the headlight of an automobile at night. That's the level of precision that we have to achieve."

If a star dims once, then dims again 10 months later, the fluctuation might be caused by a planet circling that star every 10 months. Or it might be something else, so the Kepler science team will wait another 10 months to see if the star dims again. They will also look for confirmation from ground-based telescopes.

Astronomers have found more than 300 exoplanets - planets outside our solar system. Most are not much like our own planet. Many are giants, more like Jupiter than Earth. And lead scientist William Borucki says it's impossible to know what Kepler will find.

BORUCKI: "Kepler's designed to find hundreds of earth-size planets, if such planets are common around stars. And if we find that many, it certainly will mean that life may well be common throughout our galaxy. If, on the other hand, we don't find any, it will mean that earths must be very rare; we may be the only extant life in our universe."

Astronomers should be able to use the data from Kepler to determine the size, mass, and some other characteristics of these newly discovered exoplanets. But even though Kepler is designed to find "earth-like" planets, it won't detect whether there is life on them, and astronomer Debra Fischer of San Francisco State University says the planets actually may not be much like Earth.

FISCHER: "I think that the science fiction writers are going to be challenged to imagine the diversity that we could expect to find even in these types of planets. They may not be rocky worlds. They may be water worlds. These could be worlds that in fact have life like our oceans but are perhaps not sending radio signals to us."

Fischer and lead scientist William Borucki agree that Kepler is just one step in learning about the worlds that orbit distant stars.

FISCHER: "Kepler, by virtue of the statistics that it finds, is going to tell us how frequent the occurrence of earth-sized, earth-massed planets are. And then that's going to tell us what the next step should be."

BORUCKI: "We're taking steps. The first step is what Debra talked about. Step after that, find out what's in their atmospheres. Step after that might be that our children or grandchildren send an automated probe to those stars and look for themselves."

Kepler is due to launch aboard an unmanned rocket from Cape Canaveral, Florida, on Thursday.




African innovation 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 blog that features some of the most intriguing innovations to come out of Africa.

HERSMAN: "AfriGadget is a website dedicated to showcasing African ingenuity. It's a team of bloggers and readers who contribute their pictures, videos, and stories from around the continent. And the stories of innovation are inspiring. It's a testament to Africans using creativity to overcome life's challenges."

Erick Hersman is the founder of AfriGadget.com. Don't let his American accent fool you. He grew up in Kenya and Sudan, and he and a group of fellow bloggers keep their eyes open for interesting, sometimes amusing, always engaging examples of African inventiveness.

HERSMAN: "One of my favorites is the story of Phillip Isohe, who is a Kenyan metal fabricator, but as a hobby he also creates model airplanes and buses that work. Everything works on them: lights, propellers. And he actually made the engine on them as well. So nothing is store-bought. And his story is quite inspiring as well because we wrote about him about a year and a half ago - and he ended up selling one of his model for about $400."

On AfriGadget you can learn about a Ugandan woman's homemade mobile phone charger, or do-it-yourself solar powered water disinfection, or the inventor of a rural electricity generator that uses yeast and sugar.

HERSMAN: "So it's inventors, it's micro-entrepreneurs who are just trying to do something with the little they have around them, and it's just everyday life, too. Sometimes there are just stories about kids making toys out of wire or cans or whatever they have around them. So it's a mixture of fun and practical and ingenious."

It's all about the ingenuity at AfriGadget.com, or get the link to this and more than 200 other Websites of the Week, from our site, voanews.com/ourworld.



Higher stroke risk seen in low-to-middle income countries

People who live in low-to-middle income countries face a greater risk of stroke than those living in wealthier nations. As VOA's Rosanne Skirble reports, a new study published in the British journal The Lancet Neurology finds that common risk factors often associated with stroke do not explain the global discrepancies.

SKIRBLE: According to Claiborne Johnston, neurology professor at the University of California San Francisco and the lead author of the Lancet Neurology study, stroke is not a disease exclusive to wealthy countries:

JOHNSTON: "The perception has been that stroke is a disease of high income countries of the developed world and isn't a concern in the lower income countries, and our study suggests that the opposite should be the case."

SKIRBLE: Stroke is second only to heart disease among the world's deadliest killers and accounts for 10 percent of all deaths worldwide, with the greatest burden in Eastern Europe and North Asia.

JOHNSTON: "They've been high since at least the fall of the Berlin Wall. What was new [in the study] really was an appreciation for the high rates of stroke in Central Africa and also the high rates of stroke in the South Pacific."

SKIRBLE: Those rates, Johnston says, are ten times those in the United States, Switzerland, or Israel. To help explain the difference, estimates were calculated from World Health Organization data for common risk factors like hypertension, obesity, diabetes, smoking, and alcohol abuse. With the exception of binge drinking, none explained the higher stroke incidence in lower-to-middle income countries.

Johnston suggests while some of the data may be incomplete or inaccurate, it's access to health care that divides richer nations from poorer ones.

JOHNSTON: "For example, in the U.S. it may be required that somebody be put on a breathing machine for a while after their stroke. That's not an option in a low income country."

SKIRBLE: And, Johnston says, other health factors could be at play for which no reliable measures now exist.

JOHNSTON: "We know that some infectious diseases are associated with a greater risk of stroke, in particular rheumatic fever. We don't have any measures of rheumatic fever or rheumatic heart disease in populations, and there are probably other factors that we don't know about that are also contributing to differences in stroke incidence and that also requires more study."

SKIRBLE: But Johnston says financial resources have not been directed to prevent or treat stroke in poor-to-middle income countries in part because the condition has not been considered a public health priority. I'm Rosanne Skirble


Heart disease is top killer of women, not just men

Heart disease is the world's number one killer. It's sometimes thought of as a disease of men, but that's not so. Health experts say informing women about the risk of developing the disease is the first step in preventing it. We have some advice in this report written by Faiza Elmasry and read by Faith Lapidus.

Women are more likely than ever to suffer from heart disease today, according to cardiologist Matthew Budoff.

BUDOFF: ""They are actually at increased risk because they live longer. So as they get older, they are more likely to develop high blood pressure, diabetes, and their cholesterol goes up. A lot of these issues are not discussed with their primary care physicians as diligently as men."

LAPIDUS: The first step towards fighting the disease among women, Budoff says, is dispelling the misconceptions about it, such as heart disease only affects men.

BUDOFF: "More women die of heart attack, more women die of stroke, and more women die of heart failure than men every year in the United States. So it's really a female-predominant disease at this point."

LAPIDUS: Separating facts from fiction, Budoff says, can help women make better health decisions.

BUDOFF: "Women have to make sure that they are not only doing the mammograms and self breast exams, but also finding out about their heart health. I highly recommend that women know their blood pressure, cholesterol and after menopause to consider a heart scan if they have any blood buildup in the coronary arteries."

LAPIDUS: To help prevent heart disease, registered dietitian Keri Glassman encourages women to reexamine their lifestyle.

GLASSMAN: "They 're really focusing on making small changes and building on them to improve the overall health style. We can modify many things into our daily life. We can improve our weight. We can reduce the amount of sodium we're consuming. We can incorporate more fiber and omega 3 into our diet."

LAPIDUS: Natural healthcare provider Bob DeMaria, who's known as Dr. Bob, agrees that taking care of your overall health can improve heart health.

DeMARIA: "If I was a female today, I would definitely exercise regularly. I would eat as much fresh vegetable that I could, raw, steamed or sautéd. The fruits that I'd eat would be pears, plums and apples. I would avoid pastries and all processed foods, especially the fake sweeteners."

LAPIDUS: Dr. Bob and other health advocates say it's also crucial for women to quit smoking and find creative ways to reduce their stress levels. Finding love and friendship can also help women enjoy a happier life with healthier hearts.



New book takes a naturalist's view of the human animal

Finally today ... Hannah Holmes writes science books for regular people. Over the past several years her work has included one book on the complex ecology of her suburban lawn, and another called The Secret Life of Dust.

In her latest, she writes about the human animal the way a biologist might describe an exotic species. The Well-Dressed Ape compares humans to our closest animal relatives, the primates, plus lots of other creatures in a way that gives the reader a new appreciation for what it means to be human.

I began our conversation by asking Holmes how Homo sapiens stacks up against the other creatures on our planet.

HOLMES: Well, we are really dead center in the animal kingdom. We're totally normal, typical animals in most ways. In a few ways we go off the end of a spectrum. And here's a good example. The possum, its brain uses one percent of the food that it eats. It consumes one percent of the energy budget for that animal. At the other end of the spectrum you find the human, whose brain is so huge and it has so many things to compensate for in this rather demented animal that we are, that the brain on the human consumes 20 percent of the energy. So it's all on a spectrum, but the human is so far to the end of the spectrum on some levels that it really looks like a freak.

Q: You talked about diet in the book. How does the human diet look stacked up against the diet of other animals?

HOLMES: Well, look in your mouth and you'll see a clue. We have the same mixture of teeth as a skunk or a pig or a bear, and these things are classic omnivores. You have the grinding teeth in the back for the tough plant stuff, and you have the slicing teeth in the front to cut through meat. We got a mix of everything, and that is pure, perfect data suggesting we were evolved to eat everything, and we certainly do.

Q: The range of food that we eat is matched, I guess, by the range that humans have expanded to on the planet. And biologists use this term 'range' to describe that. We seem to thrive from the equatorial rainforest right up to the arctic tundra.

HOLMES: When you look at our closest relatives, the chimps and the orangutans, those things are limited in their range to tropical forests, and there's not a lot of that left, as you know. The human, as closely related as we are, has this incredible ability to adapt to a huge variety of ecosystems, including three miles in the air in Tibet or below sea level in Holland. It's an astonishing feat.

Q: So, there was a time when humans were considered really unique in the animal kingdom in a lot of ways. One was that we used tools; other animals didn't. We communicated; other animals didn't. Today, scientists know better, and you write about that.

HOLMES: Tool use turns out to be really quite common in the animal world. There are plenty of animals out there who create tools whenever they need them, and that seems to be the key. If an animal's life style requires the use of tools, it will find a way to make and use them.

Q: And animals manage to communicate as well?

HOLMES: Yes, that's another one of those 'major distinctions' we used to treasure between us and all those wild animals is language. It turns out the prairie dog, when we hear it saying 'yip' or 'yap' is actually saying something like, 'look, there's that researcher who was here yesterday, but it looks like he's wearing a green shirt today and he's coming from the northeast.'

Q: We tend to look at our sense of smell as being pretty feeble compared to a lot of other animals. When I'm out walking a dog, the dog has his nose right there on the pavement, smelling things that I can't imagine what they're smelling. You describe that we have a vestigial sense of smell that, particularly in mating, seems to be there without us realizing it.

HOLMES: Yeah, turns out humans can smell quite a bit about each other's reproductive status. And this does seem to have a fair amount to do with reproduction. It also is the case that parents can sniff out their kids, just based on a T-shirt. And this happens within the first 18 hours after birth. But in the mating questions, smell seems to be a huge issue for humans. We seem to do a sub-conscious analysis of each other, including an analysis of the other person's immune system. And there's data that shows that humans choose each other in some cultures based on this subconscious sniff test in order to provide their kids with the ideally-matched immune systems.

Q: You write about the environment and the impact that species have on the environment. For example, one thing that stuck out for me is how elephants keep acacia trees in check, and that basically enables an entire ecosystem. The human animal, while we sometimes talk about our respect for the environment, we've probably had a greater impact on the environment of the whole planet, because of our range, than any other species.

HOLMES: Right. The human is unparalleled when it comes to altering its ecosystems to meet its own needs. It's an extraordinary animal in that way. However, it shares the exact same mandate as every other living thing, which is to control your ecosystem. This is the natural destiny of all living things. We share this with every other creature. If you gave bulldozers to the beavers, they would block up all the rivers and drown you. They would not wring their little paws over it. They would drown everything and have a zillion baby beavers.

Hannah Holmes is the author of The Well-Dressed Ape. If you'd like to hear more of my conversation with her, we've got an extended version on our website, voanews.com/ourworld.



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That's our show for this week. If you'd like to get in touch, email us at ourworld@voanews.com. Or use the postal address -

Our World
Voice of America
Washington, DC 20237 USA

Faith Lapidus is our editor. 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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