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Posted
on 28-Aug-01 09:35 AM
Nepali government defends alcohol limits
The government in Nepal has defended its decision to agree to demands by the women's wing of the Maoist rebel movement for measures to limit alcohol consumption.
The Nepali Finance Minister, Ram Sharan Mahat, told the BBC that the government's decision to make four days in every month alcohol-free was a gesture to help establish suitable conditions for dialogue with the rebels who had called for a complete ban on alcohol.
He said the liquor trade was unlikely to be much affected and the new laws would be difficult to implement.
He denied that the government had been intimidated, saying that the Maoists had little popular support and were terrorising the population by force of arms.
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Posted
on 28-Aug-01 09:38 AM
Modern humans migrated out of Africa into Central Asia before spreading both east and west into North America and Europe, says an international team of scientists who have used modern DNA analysis to trace ancient migrations.
We can trace back to regional 'Adams'
Spencer Wells
"Around 40-50,000 years ago, Central Asia was full of tropical trees, a good place for hunting and fishing," said Nadira Yuldasheva of the Institute of Immunology at the Academy of Sciences, Tashkent, Uzbekistan.
"Then, as desertification came in, some people moved west into Europe and some moved into Siberia and on into North America," she told BBC News Online.
Her colleague Professor Ruslan Ruzibakiev organised the collection of thousands of blood samples across Central Asia and the Caucusus.
Shuffling DNA
They are now working with Spencer Wells at the Wellcome Trust Centre for Human Genetics, Oxford, UK, using telltale mutations of the Y-chromosome to trace the paths of the ancient travellers.
Dr Wells explained why the Y-chromosome holds the key to tracking lines of descent.
"The cool thing about the Y-chromosome is that it doesn't recombine," he said.
When a child is created, its DNA comes from both its parents.
"The DNA is shuffled like a pack of cards," Dr Wells said.
Family tree
But if it the child is a boy, his Y-chromosome can only come from his father, since only men have Y-chromosomes.
So any mutations to the Y-chromosome, which take place naturally over time, are passed directly from father to son without any shuffling.
Researchers like Dr Wells and Dr Yuldasheva have used these inherited markers to trace a family tree of human history.
And by comparing this tree with known archaeological and linguistic facts, they believe that they have developed a more detailed understanding of how anatomically modern humans moved around the world.
Regional 'Adams'
"It looks like Central Asia was settled really early, around 40,000 years ago, as humans came out of Africa. We can trace back to regional 'Adams'," said Dr Wells.
"Our regional 'Adam's' descendants moved up to the steppe lands - probably because of climate change and then went west.
"These would have been the Cro-Magnons, the people who correspond to our popular image of the cave man," he said.
"A second wave moved along the steppe belt well to the east into the Americas," he added.
'Aryan' expansion
Dr Wells and his colleagues believe that their work also traces the expansion of the Indo-Iranian people known as the Kurgan civilisation, or more popularly Aryans.
Central Asia is revealed to be an important reservoir of genetic diversity, and the source of at least three waves of migration
Research paper
"We have a diagnostic Indo-Iranian marker," he said, referring to one of the Y-chromosome mutations.
This marker shows the progress of the 'Aryans' into India and beyond.
These Indo-Iranians spoke a language which is believed to be the forerunner of most modern tongues.
Some people living high in the mountain valleys of Central Asia still speak a form of Sogdian - the last living form of Indo-Iranian.
The study also shows how successful emigrants from Central Asia were able to spread their language further than their genes.
DNA samples from Iran show far fewer Indo-Iranian markers in the west of the country, despite an Indo-Iranian language being dominant across the region.
One explanation, said Dr Wells, could be that the incomers were so successful that the original inhabitants of the region began to adopt the newcomers' language.
Modern diversity
Modern Central Asia's diverse genetic mix is explained by the migrations that came much later, when the Silk Road carried wealth and trade goods from China to Europe and back.
These migrations are reflected in the DNA, too, and it is clear that despite the majority of modern Central Asians speaking Turkic languages, they derive much of their genetic heritage from the conquering Mongol warriors of Genghis Khan.
"Central Asia is revealed to be an important reservoir of genetic diversity, and the source of at least three waves of migration, leading into Europe, the Americas and India," the researchers wrote in the Proceedings of the National Academy of Sciences.
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Posted
on 28-Aug-01 09:41 AM
Scientists believe they have isolated the part of the brain that determines how good children are at maths.
Researchers at the Institute of Child Health at Great Ormond Street Hospital, London, found that children who were bad at calculation had a reduced amount of grey matter on the left hand side of their brains.
Grey matter is the name given to areas of the brain that are mainly composed of the heads of nerve cells.
Researchers studied 80 children who had been born prematurely.
They used brain scan images to examine anatomical abnormalities on the left parietal lobe in the children.
'Fruitful research'
It revealed the difference in grey matter between children who were good and bad at calculation.
Dr Elizabeth Isaacs, who led the study, said the research did not mean that all children with calculation problems would have the same parietal lobe anomaly.
"Imaging studies will be needed for a broader range of children," she said.
However, since the area identified has also been implicated in adult studies, it seems a fruitful area for further research.
"Diagnosis in individual children and perhaps remedial methods are an interesting area of speculation."
The results were published in the journal Brain
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| someone |
Posted
on 28-Aug-01 10:08 AM
koko,
ITS YOU AGAIN, THANKS FOR THE POSTING!
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Posted
on 28-Aug-01 11:10 AM
WASHINGTON (AP) -- The giant waves called tsunamis, long known as a danger in the Pacific Ocean, may also pose a danger to the U.S. East Coast.
While stressing that there is no indication it could happen soon, a pair of scientists is warning that a slumbering volcano on the island of La Palma, off the coast of Africa, could one day give way in a massive landslide, sending waves up to 70 feet high crashing into Florida and other coastal states.
The volcano, Cumbre Vieja, last erupted in 1949. It has not shown any recent activity.
But one day a new eruption could cause an existing rift across the volcano to split open, sending a landslide crashing into the ocean, say geophysicists Steven N. Ward of the University of California at Santa Cruz and Simon Day of University College, London.
In what they said was a worst-case scenario, a wave nearly 70-feet high could strike parts of the East Coast in only nine hours. Giant waves also could slam into Africa and northeast South America.
Ward stressed that a wave that size is unlikely, and that smaller landslides would produce waves one-fourth to half that height.
"Let's not scare people," Ward said. "Certainly there is no indication that this will happen anytime soon."
"Even when there is an eruption, the probability of collapse is low," Day said. "There may be many eruptions before the volcano is finally weak enough to collapse."
Peter Lipman, a volcanologist with the U.S. Geological Survey in Menlo Park, California, agreed that the threat exists from the volcano.
"These oceanic island volcanoes are, in geologic time, very subject to exactly the kind of process they describe," he said. "Volcanoes try to keep on adding lava to a steep slope and eventually they get the slope so loaded that it fails.
"I don't see this as something that is likely to happen very often at La Palma," he said. "But it had a failure like this half a million years ago and will again in the future."
Ward and Day's findings are reported in the Sept. 1 issue of Geophysical Research Letters.
Tsunamis, long have been known as a danger around the Pacific Ocean, where warning centers monitor the sea and alert coastal residents. They are most often generated by earthquakes or landslides under the sea and are occasionally, incorrectly, referred to as tidal waves.
The waves have not received much attention as a hazard in the Atlantic. The most recent tsunami on the East Coast occurred in 1929 when a landslide off Newfoundland created a large wave that killed 30 people in Nova Scotia, Day said.
Unlike surface waves, tsunamis reach all the way to the sea floor. In mid-ocean they may hardly be noticeable, but as they approach shore the sea floor rises and so does the wave above it, potentially rising to giant status. And they travel very fast.
The worst case scenario Ward and Day describe in their paper runs like this: Within five minutes of the collapse, a wave 1,500 feet high has zoomed 30 miles out to sea; at 10 minutes, it is down to 900 feet and slamming into nearby islands. After six or more hours, waves of 30 feet or so arrive at Newfoundland and at about nine hours, the East Coast of the United States is hit by waves ranging from 30 feet to 70 feet.
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