A wild idea to combat global warming suggests creating an artificial ring of small particles or spacecrafts around Earth to shade the tropics and moderate climate extremes.

There would be side effects, proponents admit. An effective sunlight-scattering particle ring would illuminate our night sky as much as the full Moon, for example.

And the price tag would knock the socks off even a big-budget agency like NASA: $6 trillion to $200 trillion for the particle approach. Deploying tiny spacecraft would come at a relative bargain: a mere $500 billion tops.

Conventional brush bristles, made of animal hairs, synthetic polymer fibers, and metal wires, are flimsy and prone to breaking down at the nano-scale, researchers say.

To work at the nano-scale, researchers realized that a different kind of material was needed.

"It dawned on us that [carbon] nanotubes would make excellent bristle material," Pulickel Ajayan, a professor of materials science and engineering at the Rensselaer Polytechnic Institute (RPI) in Troy, New York, said in an e-mail to National Geographic News.

Ajayan has worked with carbon nanotubes—or cylinders of carbon molecules—for more than a decade. Their small size, strength, elasticity, and ability to conduct electricity make them ideal bristle material at the nano-scale, he says.

"Governments now have a chance to make rational choices for the future, before it is too late," said ABI director of general insurance Nick Starling.

"Making the right decisions based on first class assessment of the financial costs of climate change will ensure lower costs for the public in future."

With Spain well used to high summer temperatures, many residential buildings are equipped with air conditioning which helped limit the 2003 official death toll to 101, whereas in neighbouring France, at least 14,847 people died.

French Health Minister Xavier Bertrand has therefore promised the installation of a nationwide emergency system, including a requirement that all establishments for the elderly should have at least one air-conditioned room.

Italy was also on high alert, with the health risks linked to above-normal temperatures highlighted by the release of an official report saying that almost 20,000 Italians had died in the 2003 heat wave -- more than double the previous estimate.

The Europe-wide toll for the extraordinary heat wave of 2003 had previously been estimated at around 30,000 but the Italian figure would boost it to 40,000.

It was on a fossil-hunting trip in the summer of 2000 that Leonardo's fossil was discovered. Murphy returned the following summer to excavate Leonardo, a member of the well-known species Brachylophosaurus -- a Late-Cretaceous duck-billed herbivore that grew as long as 35 feet. As his team worked on a forelimb, a volunteer saw something unusual and called to Murphy. "I took one look and said, 'Oh my God, this is skin'." When he realized he was dealing with more than a skeleton, Murphy had to revise his plan; instead of digging out the bones one by one, he had his team dig around the 23-foot-long specimen, so it could be moved to his research lab in one six-ton chunk.

Murphy hopes to transport Leonardo -- still half embedded in sedimentary rock -- to Hill Air Force Base in Utah, which has one of the world's largest CT scanners. There the heart, lung, kidneys and other organs, if they are indeed preserved inside, can be visualized and even modeled in three dimensions.

A CT scan of an entire dinosaur mummy would be an astonishing achievement, writes Adler, but no more so, perhaps, than what Mary H. Schweitzer, a biologist at North Carolina State University, accomplished with a mere fragment of T. rex bone. Schweitzer put the fossil in a weak acid and recovered a flexible substance that resembled collagen, the major organic component of bone, plus traces of red blood cells, which appear to have nuclei, holding out the possibility of recovering genetic material. And when Kent Stevens, a computer scientist at the University of Oregon, modeled on his computer the bones of the large long-necked sauropods of the late Jurassic Period, he discovered their natural position seems to lie almost parallel to the ground, or even below horizontal-an unwelcome revelation to many laymen who usually see them depicted standing foursquare with their heads high above the ground, like fat, short-legged giraffes.

To model the consequences of imitation, the researchers turned to the physics of magnets. An applied magnetic field will coerce the spins of atoms in a magnetic material to point in a certain direction. And often an atom's spin direction pushes the spins of neighbouring atoms to point in a similar direction. And even if an applied field changes direction slowly, the spins sometimes flip all together and quite abruptly.

The physicists modified the model such that the atoms represented people and the direction of the spin indicated a person's behaviour, and used it to predict shifts in public opinion.

In the case of cellphones, for example, it is clear that as more people realised how useful they were, and as their price dropped, more people would buy them. But how quickly the trend took off depended on how strongly people influenced each other. The magnetic model predicts that when people have a strong tendency to imitate others, shifts in behaviour will be faster, and there may even be discontinuous jumps, with many people adopting cellphones virtually overnight.

But Hall noted that the bees are here to stay due to the warm climate and could affect the beekeeping industry and the pollination of many crops. That's not to mention the problems they could cause to public safety, recreation and tourism.

The bee specialist said the Tampa area is seeing a small spread of them and the African bees are also being found farther inland from the ports.

There have been 14 fatalities in the United States, and hundreds of nonfatal stinging incidents have been reported, according to the report.

Nearly six months after the disaster that killed more than 31,000 people in Sri Lanka, studies have found that the tsunami waves have pushed seeds of so-called alien invasive species from their coasts farther inland on the tropical island, the United Nations Environment Program said.

"In some areas, including important national parks, the wave has encouraged the spread of alien invasive species, such as prickly pears and salt-tolerant mesquite," the agency said in a statement.

A farm worker in South Sulawesi has tested positive for the H5N1 strain of the virus, although he has shown no outward symptoms of the disease.

In the past 18 months at least 53 people across Asia are known to have died of bird flu - all of them in Cambodia, Vietnam or Thailand.

For example, they swim and climb trees. Some males go more than six miles a year to look for mates. One snake caught rainwater in its funnel-shaped coil and drank from its own cup.

"Edges aren't all that bad," said Corey Anderson, a doctoral student in biology. "Timber rattlesnakes are thought of as these sensitive, secret creatures. ... It'd be shocking to people if they knew how many den locations I have along I-44."

That would shock many people who accept the idea that snakes are a threat to humans. There were 1,245 rattlesnake bites, with only one death, reported to the American Association of Poison Control Centers in 2003. That compares to the 44 people killed by lightning in 2003, according to the National Weather Service.

"As far as regenerating parts of the brain that have degenerated, such as in Parkinson's disease, it would have major impact," said Dr. Eric Holland, a brain expert at Memorial Sloan-Kettering Cancer Center in New York.

The team also hopes that one day patients could be given a drug that enables their brain to regenerate itself.

It's a technological first. A well-placed probe fitted with 7 video cameras—6 with a 60-degree field-of-view designed to achieve a full 360-degree field-of-view (one failed during deployment, resulting in a 300-degree field-of-view) and one pointing upward—captures footage inside a tornado, providing visual data on ground wind speeds where the storm does the greatest damage.

"The scientific understanding of climate change is now sufficiently clear to justify nations taking prompt action. It is vital that all nations identify cost-effective steps that they can take now to contribute to substantial and long-term reduction in net global greenhouse gas emissions," the statement says.

In a veiled reference to President Bush's reluctance to accept climate change by claiming that the science is unclear, the academies emphasise that action is needed now to reduce the build-up of greenhouse gases.

"A lack of full scientific certainty about some aspects of climate change is not a reason for delaying an immediate response that will, at a reasonable cost, prevent dangerous anthropogenic [man-made] interference with the climate system," the statement says.

"We urge all nations... to take prompt action to reduce the causes of climate change, adapt to its impacts and ensure that the issue is included in all relevant national and international strategies."

The effort has been dubbed the Blue Brain Project. It is a daunting undertaking given the myriad of electro-chemical connections that must be mapped.

By using a supercomputer to run experiments in real time, Professor Markram hopes to accelerate substantially the pace of brain research.

"With an accurate computer-based model of the brain much of the pre-testing and planning normally required for a major experiment could be done 'in silico' rather than in the laboratory.

"With certain simulations we anticipate that a full day's worth of 'wet lab' research could be done in a matter of seconds on Blue Gene."

One of those monsters was a seven-metre long goanna lizard (Megalania prisca). An adult would have weighed up to 600 kg. Then there were the tree-climbing crocodiles, (Trilophosuchus rackhami) nicknamed the "drop crocs" for the way they are thought to have leapt down on to their victims.

"And if that didn't get you," Professor Archer said, "there were meat-eating kangaroos that would have stood up at your shoulder and torn your arm off."