This transcript is provided as a service; there may be some variation between it and the program as broadcast.
MUSIC: "Our World" theme
Straight ahead on "Our World" ... A new way to make a malaria drug ... Fixing New Orleans' levees after the hurricane ... and remembering another disaster, the 1906 San Francisco earthquake ...
STARR: "What did the damage were those firestorms and, compounded by the firestorms, was the technique of deliberately dynamiting buildings. In many instances the buildings that were dynamited actually fed the fire"
Those stories, free stuff on our Website of the Week, and more. I'm Art Chimes. Welcome to VOA's science and technology magazine, "Our World."
Scientists at the University of California have developed a way to produce a malaria drug that could lead to lower prices and thus better access to treatment for the millions of people affected by the disease.
Malaria kills more than one million people a year. The current drug of choice, artemisinin, is derived from an Asian plant, sweet wormwood. But supplies are limited, and it is relatively costly to produce.
Using a strain of yeast they have developed, the California scientists say their way of producing artemisinin has the same chemical structure as natural artemisinin, and team leader Jay Keasling says the quality will be at least as high as the naturally-derived drug.
KEASLING: "There's no reason why it shouldn't be equivalent. It will, in fact, be easier to purify because it's produced in relatively pure form in the yeast that we've engineered, so it could potentially have fewer contaminants and therefore might even be a better drug than the one that's currently available."
Keasling and his colleagues published their findings in the journal "Nature."
An international team of anthropologists has discovered fossils in eastern Ethiopia that they say might be a missing link between our earliest and more modern ape-man ancestors. Scientists say the discovery fills a major gap in human evolutionary history. VOA's Jessica Berman reports.
BERMAN: The new fossils were discovered by an international team of anthropologists in the Afar desert of eastern Ethiopia.
The latest discovery made between the year of 2000 and 2005 bridges two periods in human evolution: that of our oldest prehistoric ancestor, the four-to-seven-million year old Ardipithecus, and the more modern, 3.5 million year old Australopithecus.
"Lucy," the one meter tall adult female skeleton discovered in the Afar depression in 1974, was the most famous of the Australopithecine fossils.
The new fossils include a thigh bone, finger and hand bones, numerous teeth, a jaw bone and part of a skull, according to Tim White, a professor of integrative biology at the University of California at Berkeley. White was one of the team's leaders.
White says news of the discovery, published in the journal "Nature," helps scientists understand how humans evolved.
WHITE: "Every time you find one fossil, it fills a gap, but it creates two smaller gaps. And if we get those gaps mostly filled, then we can have a good idea of where we came from and how we evolved, the sort of where and when and how and why questions."
BERMAN: White says his team of 60 scientists from 17 countries will continue to explore their study area for even greater finds tracing back human origins. Jessica Berman, VOA News, Washington.
Seven months ago New Orleans was inundated when levees failed after being battered by hurricane Katrina. The city is built below sea level, and was protected, residents thought, by a 560-km. flood-defense system of levees, dikes, canals and pumping stations.
As engineers try to understand the catastrophic failure that left large sections of the city underwater seven months ago, VOA's Rosanne Skirble reports the race is on to repair the levees before the new hurricane season begins in just over six weeks.
SKIRBLE: The Hurricane Center at Louisiana State University issued its first advisory 45 hours before Hurricane Katrina hit landfall. Paul Kemp ? a research scientist at the Center ? knew the city of New Orleans was in trouble long before that. He had worked with the Army Corps of Engineers on models that predicted various disaster scenarios from storms the same strength as Katrina. They showed the levees were vulnerable to overtopping by storm surges or flood waters. What Kemp hadn't anticipated were the engineering problems.
KEMP "Our model had predicted where we should see water going over the levees and where we shouldn't, and some of the failures were where we didn't expect to see water going over the levees. And so we looked at those areas particularly, and in fact we found no evidence of overtopping. So, we had to conclude pretty early on that the foundations of these levees had failed rather than being scoured by water going over the tops."
SKIRBLE: Kemp is a member of an independent team that was called on by the state of Louisiana to assess the levee failures. On this overcast day he walks through a largely abandoned neighborhood of two-story brick homes, some of which were still being built when flood waters surged through the streets.
Kemp points to watermarks more than three meters high on the outside walls and to the shallow craters the water cut into in the sandy soil underneath the homes. Surveying the damage, he says the Army Corps of Engineers must understand how this happened and make moves to correct it.
KEMP: "Did overtopping [of the levees] occur prior to breaching or after breaching? What were the mechanisms of failure? Was it some bad connections between flood0walls and earthen levees as it was in many places? Was it a combination of oceanographic factors like waves and currents? [In] each of these cases ? even though we are dealing with the same storm ? we are dealing with a different causal mechanism, and they are quite different from place to place around the levee system."
SKIRBLE: After Katrina, the Army Corps began to study what went wrong. The Corps will issue its report in June. In coming weeks and months several independent teams ? like the group from Louisiana State University ? will also make assessments and recommendations. Many of these independent experts are already expressing their fears that the levees won't stand up to the next big test.
Colonel Lewis Setliff with the Army Corps of Engineers doesn't share those fears. He is commander of Task Force Guardian, the short-term levee repair team. The job to bring the levee system back to pre-Katrina conditions is well over half done. Setliff employs hundreds of Army Corps staffers. He also oversees dozens of contractors.
On this windy day, he checks progress at the London Avenue Canal where crane operators haul 25-meter sections of metal sheet pile that will form a frame for new floodgates. Two major breeches to the canal floodwalls had allowed waters to swamp the city.
SETLIFF: "The structures themselves will rise out of the water about 29 feet [8.8 meters] above sea level. And the protection they will establish will be 16 feet [4.8 meters] above sea level when the gates are closed."
SKIRBLE: "There has been criticism of some of the work that is being done here from independent panels who have been assessing the engineering. Some of the criticisms have been that you are taking shortcuts, that you are using substandard materials, that you have ignored [levee] design and construction flaws. What is your response to that?"
SETLIFF: "Well it gets back to those who criticize us just because we are moving fast that we can't build a quality product and I would contend that is not the case. We have layers and layers of quality management ? both the construction companies, independent architect-engineers, independent laboratories and the Corps of Engineers are checking our quality every step of the way because this is critical. We have to do this right. There are people's lives dependent on what we are doing. We are also inviting anyone who wants to critique us to come on site and show us the science and engineering to back their claims."
SKIRBLE: Colonel Setliff says these repairs are an interim solution. He says the Corps is committed to building a "higher and better" levee system based on lessons learned from its own study and that of independent analysts. Professor Paul Kemp from Louisiana State University says in the meantime, the City of New Orleans hangs in the balance.
KEMP: "Now the question is, you can build something that looks like a levee in three months, but will it actually hold the water back?"
SKIRBLE: The answer could come when hurricane season begins on June 1. In New Orleans, I'm Rosanne Skirble
Time again for our Website of the Week, and this time it's a way of getting rid of things you don't need, helping the environment, and getting free stuff.
BEAL: "Freecycle.org is a website where people give things away instead of throwing them away. And our ultimate goal is a worldwide gift economy online."
Deron Beal is the founder of Freecycle.org. It's a nonprofit organization that links some 3,000 local groups in more than 70 countries. Within each group, members offer items they don't want to anyone else in the group, for free. What sort of items? Well, to give you an idea, some listings from a Freecycle group in the Washington area include cigar boxes, baby products, furniture, and camping gear. If there's a Freecycle group in your country, the mix is probably different. But Beal says there is no typical listing.
BEAL: "(laughs) You got it. There really is no 'typical.' It is funny, though. I suppose it depends on the country and what's out there. But there's really no limit, and it's whatever the individually locally wishes to give away. That's what we see being posted."
Between the fitness gadgets, the kitchen appliances, toys, and everything else, it works out to a lot of stuff.
BEAL: "Currently we're keeping over 200 tons a day out of landfills. That's the equivalent of a midsize landfill. So that's a lot of stuff."
There are Freecycle groups throughout the United States, but coverage is spotty in other countries. However, new groups are forming all the time, and anyone can start one. For now, the site is English-only, which obviously is a limitation, and Deron Beal says he hopes to change that soon. The site is Freecycle.org, or get the link from our site, VOANews.com/ourworld.
MUSIC: "People Got To Be Free" (Felix Cavaliere with Ringo Starr and his All-Starr Band)
And you're listening to VOA's science and technology magazine, Our World. I'm Art Chimes in Washington.
This coming Tuesday marks the 100th anniversary of the 1906 San Francisco earthquake, one of North America's greatest natural disasters. As we hear from reporter Jan Sluizer, it was a tragedy that also gave birth to modern earthquake science.
SLUIZER: A century ago, San Francisco was California's biggest city, and at five a.m. on Wednesday, April 18, the city was starting to wake up. Then, at 5:12 a.m., the earth shifted. History professor and former California State Librarian Kevin Starr says there were two jolts, the second one lasting 40 seconds.
STARR: "You don't have panic. You don't have noise. You have a period of silent shock and awe. What had happened? And people came out on the street, looked to each other, looked around and said, What has happened? What has happened?"
SLUIZER: What had happened was that an earthquake ? today estimated at magnitude 7.9 violently shook the city. Gas lines broke, 60 fires broke out, and the water system failed.
STARR: "As devastating as the earthquake was, it did not completely destroy the city. What did the damage were those firestorms and, compounded by the firestorms, was the technique of deliberately dynamiting buildings. In many instances the buildings that were dynamited actually fed the fire."
SLUIZER: Today there are fewer than a dozen survivors of the disaster. One of them, Herb Hamrol, 103 years old and still working part-time at a local supermarket, was three years old when the earthquake hit.
HAMROL: "I remember my mother carrying me down the stairs and we slept in the park close by for two nights."
SLUIZER: The 1906 disaster marked the birth of earthquake science in America. Even as the fires raged for three days, California's governor rounded up 20 of the states leading scientists. They were challenged to investigate how and why the earths crust had ruptured with such terrifying violence. Ross Stein, a geophysicist with the United States Geological Survey, says that four years later they produced the Lawson Report, which laid the foundation for much of what is known today about earthquakes.
STEIN: "Before the 1906 earthquake most scientists thought that an earthquake involved shaking of the ground but not any permanent displacements of the ground. What the Lawson report did was to show us that sudden movement along a fault, a zone of weakness in the earth, produces the earthquake shaking. In addition to producing the shaking, which is what we all feel, it produces permanent displacement of the land."
SLUIZER: Author Susanna Hoffman, who has written on the anthropology of disasters, says that people are in a state of denial when they choose to live in a place like California, where earthquakes are always a potential danger.
HOFFMAN: "Most Californians who've decided to live here decided its a calculatable risk, its an okay risk. People think: Well, its not going to do that much damage, they don't kill that many people. And actually that is quite true. What kills people is what happens afterwards."
SLUIZER: Elke DeMuynck lives directly on top of the Hayward fault, the most dangerous of the seven earthquake faults that criss-cross the San Francisco Bay Area because it is due to snap at any time. Although her house shakes every couple of weeks, she says she doesn't give it a thought or think about the danger on a daily basis.
DeMUYNCK: "Not that I have a false sense of security. But I'd rather live somewhere where the possibility of having an earthquake is, you know, maybe slim-to-none in my lifetime. But I could be living somewhere like where they're having floods and tornadoes and hurricanes which is a given every year, and I don't know if I could deal with that."
SLUIZER: The San Francisco Earthquake and Fire of 1906 is being marked by dozens of commemorative events. On April 18th, the city will mark the anniversary with the traditional wreath-laying at historic Lottas Fountain, a landmark that survived the disaster. At 5:12 a.m. there will be a moment of silence, followed by a citywide bell ringing and the traditional singing of the city's anthem, San Francisco. I'm Jan Sluizer in San Francisco.
MUSIC: "San Francisco" sung by cast of Beach Blanket Babylon
Video technology seems to march forward at a relentless, accelerating pace.
This month the Walt Disney Company announced that it would make several popular programs from its ABC television network in the United States available for free online viewing one day after they're shown on TV.
DVDs hit the market a decade ago, but before that home video was dominated by the VHS format, which dates to the mid-'70s. Other formats came and went during the years, but in a way they are all direct descendants of a product introduced 50 years ago this week ? the first commercially practical videotape recorder, developed by California-based Ampex Corporation.
Until that point, the only way to preserve a television broadcast was something called a kinescope recording, explains Gregory Lukow of the Library of Congress.
LUKOW: "Kinescopes are actually filmed records of television programs that were made simply by pointing usually a 16 mm camera at a monitor and making a record of what was shown on the air."
As the head of the library's television collection, Lukow is happy to have the surviving kinescopes, but broadcast historian Pete Hammar says that in the early '50s the industry was unhappy with the status quo.
HAMMAR: "People were desperate for a replacement for this process because, first of all they were very expensive, second the quality was very bad. You knew you were watching a recorded program when you were watching a kinescope-delayed show."
Hammar worked with Ampex for a decade and set up the company's museum.
Ampex was founded in the 1940s by Russian émigré Alexander Poniatoff. It was an industry-leader in professional audio recording, and the company set out to develop a way of recording video onto magnetic tape. But as Pete Hammar points out, video contains a lot more information than audio.
HAMMAR: "The original idea of recording television on tape was to take audio tape and run it very quickly, very fast. The problem is you ended up with a reel of tape about a half-meter in diameter that lasted only four minutes. Not exactly practical, but it was an idea. Ampex in 1956 came up with the only real practical way to do video recording on magnetic tape, which is to spin a head, a set of heads spinning rapidly past a slow-moving tape, rather than fixed heads that were being passed by a fast-moving tape."
That breakthrough remains the basis of all videotape machines today, from network control rooms to the home video cassette players connected to untold millions of TV sets worldwide.
Ampex introduced its new videotape recorder at a trade show in Chicago in April 1956. The first generation Ampex VR-1000 recorders sold for about $50,000 ? a tremendous amount of money back then. But buyers got a lot for their money. The electronics were not miniaturized, and the machine was overbuilt to handle the rigors of a reel of five-centimeter wide tape. The whole setup weighed about a ton.
Aside from the cost and size, another limitation of that first generation of video recorders was the difficulty in editing programs. Later machines had electronic editing systems, but at first the tape had to be physically cut, and very carefully. Vic Vissari, a technician at Washington's WRC-TV, recalls the challenge.
VISSARI: "You had to mark the tape physically with a Magic Marker and cut between the video segments on the tape. And you would put [on] the editing solution, is what it's called. It looked like graphite mixed in alcohol. And you could see the video tracings through a little magnifying glass. And you had to make sure that the tape on the other side didn't have the residue of the editing solution or it would not stick. And a lot of these [splices] came apart on the air."
Videotape came to dominate television, of course, and the technology is so good that you can't tell if you're watching professional-quality videotape, or a live broadcast. But for historians and archivists, like Greg Lukow of the Library of Congress, the short term quality advantage of video recording has long-term disadvantages.
LUKOW: "Videotape, as with all tape-based magnetic media, is a very, very poor archival preservation media. Unlike film, which if properly processed and stored, can last hundreds of years, [with] videotape we're often counting in just a couple of decades or less."
In addition, Lukow says the constant evolution of different formats presents a different challenge: the tape itself is worthless unless you've got a machine to play it on.
And from an archival standpoint, one of the greatest shortcomings of videotape derives from one of its biggest selling points: because tape can be erased and reused, and in the early days it was very expensive, countless hours of news and entertainment recordings are lost forever because the tape was erased and used to record something else.
MUSIC: "Our World" theme
That's our show for this week. Drop us a line, let us know what you think. We're always happy to hear from you. If you've got a science question, and we answer it on the air we'll send you a special VOA gift as our way of saying thanks. The email is email@example.com. Or use our postal address -
Voice of America
Washington, DC 20237 USA.
The show was edited by Rob Sivak. Eva Nenicka is our 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.