The sick and dying waterfowl can be easily spotted at the Lake Qinghai nature reserve. If not paralyzed, they stagger and have tilted necks, classic symptoms of avian flu in such birds.
The outbreak was first detected on April 30 and within three weeks; it killed about 1,500 birds, mostly geese, but also two gull varieties. Now, the World Health Organization estimates that about 6,000 have died.
In a new paper in the journal Nature, Chinese scientists say this is the first evidence that avian flu transmission has spread beyond domesticated poultry into wild bird populations far away from farms. Hong Kong University researcher Yi Guan says the expansion could signal an even further spread of the disease once the flocks begin migrating from the Chinese lake.
Yi Guan: You already know we have a big problem in Southeast Asia. Now this has become a new challenge for us.
Mr. Yi and colleagues say the infected bar-headed geese at the lake are capable of flying over the Himalayas at a range of 16 hundred kilometers a day.
That migration will not be long in coming. Microbiologist George Gao of the Chinese Academy of Sciences in Beijing says the birds breed at the lake from the end of April only until the end of July.
George Gao: So they are flying out, soon. The problem is if there is any carrier, they might carry this to Tibet, India, and Southeast Asia. So that is something we're worried [about]. But whether or not some survivors will carry the virus, we don't know yet.
Mr. Gao's team reports in the journal "Science" that they isolated several viruses from the birds and found that each shows the genetic hallmarks of a highly virulent strain. According to the "Nature" article by Yi Guan's group in Hong Kong, it is closely related to the strain that has infected poultry and people in Thailand and Vietnam.
Public health experts fear that it will merge with human influenza in a patient and create a strain that more easily circulates among people and causes a global pandemic that kills millions.
World Health Organization spokesman Dick Thompson says the birds at the Chinese nature reserve should be watched closely.
Dick Thompson: There's an urgent need to sample and tag and track as many of these species as feasible, especially considering the narrow time frame that we've got available to do it. We need more information on the migratory routes regarding these birds.
The World Health Organization has urged China to increase its testing of the wild geese and gulls.
David McAlary, VOA news, Washington.
2008年9月29日星期一
Science Editors Take a Closer Look at 125 Great Unsolved Mysteries
Science Magazine is celebrating its 125th birthday with a special issue that takes stock of some of the fundamental and still unsolved mysteries of our time. The magazine's editors compiled 125 questions that point out the gaps in our scientific understanding of the universe we live in.
Inventor Thomas Edison founded Science Magazine in 1880. Today, as the weekly publication of the American Association for the Advancement of Science, it boasts the largest circulation of any scientific journal in the world.
News editor Colin Norman says instead of looking back at papers published over the last 125 years, the magazine decided to tap the expertise of more than 100 reviewing editors to help it compile a list of 125 questions that focus on the limits of our knowledge -- questions such as, 'What is the universe made of?'
Mr. Norman: We now know that the fraction of the universe that you can actually see - the stars and galaxies, is just a very very tiny fraction of what's there. There is a lot of dark matter that we know is there that is holding the galaxies together. Some of this is just regular matter, but a lot of it (is) particles that we don't know what they are yet.
Editor Colin Norman says other questions are much more specific, 'Can we produce an HIV vaccine that is effective? A big problem that has tremendous social consequences.
Editors found that questions are not so simple and one leads to the next. Take, for example, the human genome, the hereditary DNA sequence first mapped 5 years ago. Scientists were puzzled when they discovered humans have just 25,000 genes, much less than the 100,000 they had expected.
Mr. Norman: Having answered the question 'How many genes do we have?' We now have to answer the question, 'How can we be so complicated with so few genes?' And it has to do with how the genes are expressed, the way the genome is controlled, and so there are a whole series of really interesting questions that are opened up by that discovery that we really have very few genes.
Even though the magazine came up with a symbolic number of questions on the occasion of its 125th year, Colin Norman admits they are only a small fraction of the puzzles that scientists are actually struggling to solve. Mr. Norman invites listeners to take a look at the list online at sciencemag.org and let him know if there's an unsolved scientific mystery the editors might have missed.
I’m Rosanne Skirble.
Inventor Thomas Edison founded Science Magazine in 1880. Today, as the weekly publication of the American Association for the Advancement of Science, it boasts the largest circulation of any scientific journal in the world.
News editor Colin Norman says instead of looking back at papers published over the last 125 years, the magazine decided to tap the expertise of more than 100 reviewing editors to help it compile a list of 125 questions that focus on the limits of our knowledge -- questions such as, 'What is the universe made of?'
Mr. Norman: We now know that the fraction of the universe that you can actually see - the stars and galaxies, is just a very very tiny fraction of what's there. There is a lot of dark matter that we know is there that is holding the galaxies together. Some of this is just regular matter, but a lot of it (is) particles that we don't know what they are yet.
Editor Colin Norman says other questions are much more specific, 'Can we produce an HIV vaccine that is effective? A big problem that has tremendous social consequences.
Editors found that questions are not so simple and one leads to the next. Take, for example, the human genome, the hereditary DNA sequence first mapped 5 years ago. Scientists were puzzled when they discovered humans have just 25,000 genes, much less than the 100,000 they had expected.
Mr. Norman: Having answered the question 'How many genes do we have?' We now have to answer the question, 'How can we be so complicated with so few genes?' And it has to do with how the genes are expressed, the way the genome is controlled, and so there are a whole series of really interesting questions that are opened up by that discovery that we really have very few genes.
Even though the magazine came up with a symbolic number of questions on the occasion of its 125th year, Colin Norman admits they are only a small fraction of the puzzles that scientists are actually struggling to solve. Mr. Norman invites listeners to take a look at the list online at sciencemag.org and let him know if there's an unsolved scientific mystery the editors might have missed.
I’m Rosanne Skirble.
Extreme Weather Having Effects Worldwide
We expect uncomfortably hot temperatures in midsummer, even violent weather in certain areas. But this year, North America has been hit by some unusually wild, record-setting storms.
Matthew Lopez is Chief of Emergency Management in Escambia County, Florida.
Matthew Lopez: This is the most active tropical storm season and hurricane season we've seen in the history of North America.
This is Florida resident Shannon Bartell.
Shannon Bartell: So it's been scary today. I've never been this scared in my whole life.
Recently, Hurricane Dennis roared through the U.S. southern state of Florida, with 193-kilometer winds. Tropical Storm Emily is expected to hit U.S. shores in the next few days. Emily is a record-setting fifth named-storm this season.
Some hurricanes affecting North America's East Coast typically originate in the Atlantic Ocean near the African coast. Strong winds from Africa mixing with the warm ocean air can destabilize the air sufficiently to cause thunderstorms, and later, hurricanes.
Hurricanes and floods aren't the only weather concerns. Drought conditions are also prevalent in some parts of the world, causing some, like Illinois farmer Mark Yonkers, to worry.
Mark Yonkers: Normally, the leaves will all be opened up, and a lot fuller looking than what it is.
The U.S. corn crop is in its key pollination stage, and needs rain. But Illinois, the second largest corn-producing U.S. state, is experiencing its worst drought in 20 years.
France, too, is in the midst of a drought, leading authorities to call for water restrictions.
Deputy Director of French weather forecast center Meteo-France Alain Ratier:
Alain Ratier: The main part which is severely affected is the western part of France, the southwestern part in fact where we have a lot of difficulties with agriculture...
Severe weather has hit Europe hard this summer. Fires from hot, dry weather in some regions, and heavy floods in others have killed dozens.
Extreme weather also hurts the global economy. Hurricane Dennis caused significant damage to an oil platform on the Gulf Coast, and extended periods of drought will cause produce prices to rise.
But the main concern is the immediate damage, injury and even death severe weather can bring, driving some to despair:
One hurricane victim: I think we're cursed. I think someone doesn't want us to live here.
Ernest Leong, VOA news.
Matthew Lopez is Chief of Emergency Management in Escambia County, Florida.
Matthew Lopez: This is the most active tropical storm season and hurricane season we've seen in the history of North America.
This is Florida resident Shannon Bartell.
Shannon Bartell: So it's been scary today. I've never been this scared in my whole life.
Recently, Hurricane Dennis roared through the U.S. southern state of Florida, with 193-kilometer winds. Tropical Storm Emily is expected to hit U.S. shores in the next few days. Emily is a record-setting fifth named-storm this season.
Some hurricanes affecting North America's East Coast typically originate in the Atlantic Ocean near the African coast. Strong winds from Africa mixing with the warm ocean air can destabilize the air sufficiently to cause thunderstorms, and later, hurricanes.
Hurricanes and floods aren't the only weather concerns. Drought conditions are also prevalent in some parts of the world, causing some, like Illinois farmer Mark Yonkers, to worry.
Mark Yonkers: Normally, the leaves will all be opened up, and a lot fuller looking than what it is.
The U.S. corn crop is in its key pollination stage, and needs rain. But Illinois, the second largest corn-producing U.S. state, is experiencing its worst drought in 20 years.
France, too, is in the midst of a drought, leading authorities to call for water restrictions.
Deputy Director of French weather forecast center Meteo-France Alain Ratier:
Alain Ratier: The main part which is severely affected is the western part of France, the southwestern part in fact where we have a lot of difficulties with agriculture...
Severe weather has hit Europe hard this summer. Fires from hot, dry weather in some regions, and heavy floods in others have killed dozens.
Extreme weather also hurts the global economy. Hurricane Dennis caused significant damage to an oil platform on the Gulf Coast, and extended periods of drought will cause produce prices to rise.
But the main concern is the immediate damage, injury and even death severe weather can bring, driving some to despair:
One hurricane victim: I think we're cursed. I think someone doesn't want us to live here.
Ernest Leong, VOA news.
Miracle Baby Girl is Born to Brain-Dead Mother
Just three months ago, Susan Torres was a vibrant young mother who was 15 weeks pregnant with what she hoped would be a baby girl. On May 8th, all of that changed when she lost consciousness from a stroke after an aggressive cancer spread to her brain.
Her husband Jason feared the worst.
Jason: The doctor said there was no brain function. But she was young and pregnant and already has a child, so they will give it a shot.
With machines keeping the brain-dead woman's body alive, doctors hoped to allow the child to be born. Jason Torres believes this would have been his wife's final wish.
Jason: Without question, I know that Susan would walk through hell and back just to give her child a chance.
As the fetus developed, the mother's cancer continued to spread. As the weeks went on, doctors worried it could threaten the unborn child.
On Tuesday, doctors gave the child a final chance at survival. They performed a caesarian section and delivered a baby girl, Susan Ann Catherine Torres, weighing in at less than a kilogram.
Dr. Donna Tilden-Archer, Medical Director of the Neonatology unit at the Virginia Hospital Center, says for a child born nearly three months early, Baby Torres is doing quite well.
Donna Tilden-Archer: At the moment she was born she was very vigorous and crying and in very good condition for a baby of her gestational age.
The birth however was bittersweet for Susan Torres' family. On Wednesday morning, with her family by her side, Susan Torres passed away when the machines that had sustained her life for the past 12 weeks were turned off.
Family spokesman Justin Torres reflected on Susan's final days.
Justin Torres: Susan was always the toughest person in that ICU room. Her passing is a testament to the truth that human life is a gift from God and that children are always to be fought for even if life requires, as it did of Susan, the last full measure of devotion.
A mother's final gift to the daughter she'll never know.
Jim Bertel, VOA news.
Her husband Jason feared the worst.
Jason: The doctor said there was no brain function. But she was young and pregnant and already has a child, so they will give it a shot.
With machines keeping the brain-dead woman's body alive, doctors hoped to allow the child to be born. Jason Torres believes this would have been his wife's final wish.
Jason: Without question, I know that Susan would walk through hell and back just to give her child a chance.
As the fetus developed, the mother's cancer continued to spread. As the weeks went on, doctors worried it could threaten the unborn child.
On Tuesday, doctors gave the child a final chance at survival. They performed a caesarian section and delivered a baby girl, Susan Ann Catherine Torres, weighing in at less than a kilogram.
Dr. Donna Tilden-Archer, Medical Director of the Neonatology unit at the Virginia Hospital Center, says for a child born nearly three months early, Baby Torres is doing quite well.
Donna Tilden-Archer: At the moment she was born she was very vigorous and crying and in very good condition for a baby of her gestational age.
The birth however was bittersweet for Susan Torres' family. On Wednesday morning, with her family by her side, Susan Torres passed away when the machines that had sustained her life for the past 12 weeks were turned off.
Family spokesman Justin Torres reflected on Susan's final days.
Justin Torres: Susan was always the toughest person in that ICU room. Her passing is a testament to the truth that human life is a gift from God and that children are always to be fought for even if life requires, as it did of Susan, the last full measure of devotion.
A mother's final gift to the daughter she'll never know.
Jim Bertel, VOA news.
US Law Could Block Astronaut Activities on
Now that the U.S. space shuttle Discovery is back on Earth, future shuttle missions are postponed until the space agency NASA solves the problem of launch debris endangering the orbiters. Whenever missions resume, they will continue building the International Space Station, which the United States operates with Russia and the support of Europe, Canada, and Japan. But there is a legal obstacle that may keep U.S. astronauts off the Space Station.
The issue dates back to 1996, when the two countries agreed that Russia would provide the United States free crew and cargo transportation to the station until next April. This provision proved crucial during the long ban on shuttle flights after the Columbia disaster in 2003, for the United States had no other way to get its astronauts and supplies to the station.
But the agreement is nearing an end. According to Marcia Smith of the U.S. Congress' research service, the final free round trip Soyuz spacecraft ride for a U.S. astronaut to the station is to lift off in October with a planned April return.
Marcia Smith: Right now, The United States doesn't have any guaranteed access to the space station after next April, when Russia will have fulfilled its obligations. We don't know if the shuttle will be flying or not, but if it is flying, then the astronauts will be able to stay there only when the shuttle is there.
The U.S.-Russian agreement made sense at a time when shuttles flew regularly and NASA envisioned an April completion date for the station. For the period after that, NASA had planned to have a special escape vehicle that U.S. crews could use in case of a space station emergency, freeing them from reliance on Soyuz craft. But Marcia Smith says the Bush administration canceled plans for such a lifeboat.
Marcia Smith: The United States was going to build its own, but it decided not to because there were cost overruns and other factors. So for a [U.S.] crew member to stay on the space station after the shuttle leaves, that crew member has to have access to a seat in a lifeboat, and, once again, Russia's obligations to provide that to NASA for free will end in April of 2006.
An obvious solution would be for NASA to buy Russian space transportation services. But a five-year-old U.S. law prohibits such payments unless President Bush confirms that Moscow has not provided Iran with missile or weapons technology in the previous year.
In a recent House of Representatives hearing, Congressman Dana Rohrabacher told NASA's new chief, Michael Griffin, that the law has failed to stop Iran's nuclear weapons program. He blames the Bush administration and the previous Clinton government for not taking diplomatic steps to prevent Moscow from providing technical help to Tehran.
Michael Griffin: What needed to happen was some type of overture to the Russians that would give them an alternative. Neither administration did its job in the past and now you, after two months as being leader of NASA, are faced with this very serious time period when decisions have to be made.
The Bush administration wants Congress to amend the U.S. law so NASA can begin buying services from its Russian counterpart.
But congressional researcher Marcia Smith says there are ways around the measure. It allows exceptions for payments to prevent imminent loss of life aboard the station or to help maintain the Russian module. She says President Bush could declare such exceptions. He could also conclude that the act does not apply to the Russian manufacturer of Soyuz spacecraft and let NASA buy some for its own use.
Retired U.S. government physicist Albert Wheelon, a member of the commission that investigated the 1986 shuttle Challenger explosion, says another alternative is to renegotiate the U.S.-Russian agreement to continue free services to NASA. But he thinks that a financially struggling Russian space agency would be unlikely to do this.
Albert Wheelon: I think we have painted ourselves into a serious corner here, I think it unlikely that they would refuse a rescue plea. The idea of doing 28 more missions I think is probably beyond the bounds of their generosity.
NASA chief Michael Griffin says this dilemma is a major reason why he wants to replace the aging space shuttle fleet by 2010 with a more agile astronaut craft that will allow the United States to maintain its independence in space.
David McAlary, VOA news, Washington
The issue dates back to 1996, when the two countries agreed that Russia would provide the United States free crew and cargo transportation to the station until next April. This provision proved crucial during the long ban on shuttle flights after the Columbia disaster in 2003, for the United States had no other way to get its astronauts and supplies to the station.
But the agreement is nearing an end. According to Marcia Smith of the U.S. Congress' research service, the final free round trip Soyuz spacecraft ride for a U.S. astronaut to the station is to lift off in October with a planned April return.
Marcia Smith: Right now, The United States doesn't have any guaranteed access to the space station after next April, when Russia will have fulfilled its obligations. We don't know if the shuttle will be flying or not, but if it is flying, then the astronauts will be able to stay there only when the shuttle is there.
The U.S.-Russian agreement made sense at a time when shuttles flew regularly and NASA envisioned an April completion date for the station. For the period after that, NASA had planned to have a special escape vehicle that U.S. crews could use in case of a space station emergency, freeing them from reliance on Soyuz craft. But Marcia Smith says the Bush administration canceled plans for such a lifeboat.
Marcia Smith: The United States was going to build its own, but it decided not to because there were cost overruns and other factors. So for a [U.S.] crew member to stay on the space station after the shuttle leaves, that crew member has to have access to a seat in a lifeboat, and, once again, Russia's obligations to provide that to NASA for free will end in April of 2006.
An obvious solution would be for NASA to buy Russian space transportation services. But a five-year-old U.S. law prohibits such payments unless President Bush confirms that Moscow has not provided Iran with missile or weapons technology in the previous year.
In a recent House of Representatives hearing, Congressman Dana Rohrabacher told NASA's new chief, Michael Griffin, that the law has failed to stop Iran's nuclear weapons program. He blames the Bush administration and the previous Clinton government for not taking diplomatic steps to prevent Moscow from providing technical help to Tehran.
Michael Griffin: What needed to happen was some type of overture to the Russians that would give them an alternative. Neither administration did its job in the past and now you, after two months as being leader of NASA, are faced with this very serious time period when decisions have to be made.
The Bush administration wants Congress to amend the U.S. law so NASA can begin buying services from its Russian counterpart.
But congressional researcher Marcia Smith says there are ways around the measure. It allows exceptions for payments to prevent imminent loss of life aboard the station or to help maintain the Russian module. She says President Bush could declare such exceptions. He could also conclude that the act does not apply to the Russian manufacturer of Soyuz spacecraft and let NASA buy some for its own use.
Retired U.S. government physicist Albert Wheelon, a member of the commission that investigated the 1986 shuttle Challenger explosion, says another alternative is to renegotiate the U.S.-Russian agreement to continue free services to NASA. But he thinks that a financially struggling Russian space agency would be unlikely to do this.
Albert Wheelon: I think we have painted ourselves into a serious corner here, I think it unlikely that they would refuse a rescue plea. The idea of doing 28 more missions I think is probably beyond the bounds of their generosity.
NASA chief Michael Griffin says this dilemma is a major reason why he wants to replace the aging space shuttle fleet by 2010 with a more agile astronaut craft that will allow the United States to maintain its independence in space.
David McAlary, VOA news, Washington
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