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US firmly anti-Kyoto as UN climate talks start
The United States shows no signs of budging in its opposition to the Kyoto protocol as UN climate change talks began in Buenos Aires, a month after President Bush’s re-election and Russia’s ratification of the agreement.
The US government said it had “chosen a different path” from Kyoto, but vowed to work against global warming by slowing greenhouse gas emissions, investing in climate science and technology and cooperating internationally.
Bush withdrew in 2001 from the 128-nation Kyoto protocol, which seeks to cut carbon dioxide emissions by five percent from 1990 levels by 2012. He argued it was too expensive and wrongly excluded developing nations.
Of the large industrialized countries, only the United States and Australia have refused to join the UN effort. They account for around one-third of global emissions.
The Australian government says ratifying Kyoto would hike power prices and cost the country jobs. Scientists predict the rise in temperatures will accelerate melting glaciers and polar ice caps, leading to a rise in sea levels, extreme weather like heat waves, the spread of tropical diseases and the collapse of forests, coral reefs and farming.
“Efforts to address climate change will only be sustainable if they also serve a larger purpose of fostering prosperity and well-being for citizens around the globe,” Harlan Watson, alternate head of the US. delegation, told the Buenos Aires conference to the parties, known as COP 10.
Russia’s ratification has created the most optimistic mood in years among environmentalists since it allows Kyoto to go into effect in February with a seven-year delay.
Lost sleep
People who put on a few extra pounds may be able to blame a lack of sleep for the added weight, according to two separate studies.
Losing sleep can raise levels of hormones linked with appetite and eating behaviour, the researchers said.
In one study, people who slept only four hours a night for two nights had an 18 per cent reduction in leptin, a hormone that tells the brain there is no need for more food, and a 28 percent increase in ghrelin, which triggers hunger.
The young men in the study also tended to eat more sweet and starchy foods when sleep was cut short.
“We don’t yet know why food choice would shift,” said Eve Van Cauter, a professor of medicine at the University of Chicago who led the study. “Since the brain is fueled by glucose, we suspect it seeks simple carbohydrates when distressed by lack of sleep.”
Van Cauter and colleagues wrote in the Annals of Internal Medicine that they studied 12 healthy men in their early 20s. They measured circulating levels of leptin and ghrelin before the study, after two nights of only four hours in bed, and after two nights of ten hours in bed.
“We were particularly interested in the ratio of the two hormones — the balance between ghrelin and leptin,” Van Cauter said. After four hours of sleep, the ratio of ghrelin jumped 71 percent compared to a night when the men slept nine hours.
A second study found that the less people sleep, the more they weigh, using a measure called body mass index, which scales weight to height. It also found lower leptin levels and higher ghrelin levels in people who slept less.
Human-like chimp brain
New research provides more evidence that chimpanzee brains are human-like in terms of the links between brain asymmetry, language and right- or left-handedness
In one study, researchers used magnetic resonance imaging to study two key structures — the hippocampus and amygdala — in the brains of 60 chimpanzees. Both structures are part of the limbic system.
The MRI images revealed that the right side of the hippocampus was much larger than the left side. This asymmetry was more pronounced in males. Human hippocampi are also asymmetrical in the same way. The amygdalas of the chimps were symmetrical, the same as in humans.
“The limbic system asymmetries advance the position that asymmetries are fundamental aspects of the nervous system of all primates, and apply to more primitive systems in the brain,” researcher William Hopkins, of the Yerkes National Primate Research Center in Atlanta, said in a prepared statement.
These asymmetries influence behaviors such as facial expression and spatial memory, Hopkins said.
A second study found the first-ever evidence of an association between hand preference and asymmetries in three regions of the chimpanzee brain cortex.
The findings appear in the December issue of Behavioral Neuroscience.
‘Thinking Cap’
Four people were able to control a computer using their thoughts and an electrode-studded “thinking cap,” US researchers report.
They said their set-up could someday be adapted to help disabled people operate a motorized wheelchair or artificial limb. While experiments have allowed a monkey to control a computer with its thoughts, electrodes were implanted into the animal’s brain. This experiment, reported in the Proceedings of the National Academy of Sciences, required no surgery and no implants.
“The results show that people can learn to use scalp-recorded electroencephalogram rhythms to control rapid and accurate movement of a cursor in two dimensions,” Jonathan Wolpaw and Dennis McFarland of the New York State Department of Health and State University of New York in Albany wrote.
They tested their device on four people — two partly paralyzed men who used wheelchairs and a healthy man and woman.
During the experiments, the four volunteers faced a video screen wearing a cap that held 64 electrodes against the scalp to record brain activity.
Many groups are working on ways to help disabled and paralyzed people use their thoughts to control machines. While some require brain implants, others use such cues as eye motion or brain waves recorded from outside. — Sci-tech World Report
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