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| SCIENCE & TECHNOLOGY |
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Atmospheric pollution?
THIS UNIVERSE
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Atmospheric pollution?
“Geo-engineering” sounds like a bland and technical term — but it is actually a Messianic movement to save the world from global warming, through dust and iron and thousands of tiny mirrors in space. It is also the last green taboo. Environmentalists instinctively do not want to discuss it. The wider public instinctively think it is mad. But recently the taboo was breached. James Lovelock — one of the founding fathers of modern environmentalism — proposed a way to slash global warming without cutting back on a single fossil fuel.
“Geo-engineers” believe that man should consciously change the planet’s environment, using technology, to counter the effects of global warming. They are like a chef who realises she has accidentally put in too much cayenne, so reaches for lashings of oregano to balance it out, only this time the recipe is the atmosphere of the planet earth. Ken Caldeira, a geo-engineering expert at the Carnegie Institute, says: “In effect, we’re already engineering the climate by emitting so many greenhouse gasses. We just don’t want to admit it. You can argue that the only reason difference between what we’re doing today and what geo-engineering advocates are proposing is a matter of intention. And frankly, the atmosphere doesn’t care about what’s going on in our heads.” Grand geo-engineering schemes come in two main flavours. The first tries to increase the oceans’ capacity to absorb carbon from the atmosphere. At the moment, the oceans are, along with the rainforests, the most effective natural mechanism for taking carbon out of the atmosphere. So geo-engineers ask: is there anything we can we do to supercharge them? The simplest proposal is to sprinkle vast amounts of iron along the surface of the world’s seas. This would create the ideal conditions for a surge in the quantity of plankton, the friendly micro-organisms who “eat” carbon while they are alive. When they die, they sink to the bottom of the ocean taking the carbon with them, for centuries, to a watery grave. It has been tried in a number of small-scale experiments off the coast of the Galapagos Islands and it did indeed cause dead seas to spring to life with carbon-sucking plankton. Enter James Lovelock, with a similar proposal. He suggests another way to spur the oceans to sink massive amounts more of carbon dioxide. His plan is to build vast vertical pipes across the world’s seas. They would pump water from the bottom of the oceans rich in nutrients, but mostly dead to the top. This rich water would be ideal for micro-organisms such as salps to breed in. They too “eat” carbon and then excrete it, where it sinks to the floor of the ocean. The second school of geo-engineering projects tries to reflect much more of the sun’s energy back into space, so it doesn’t stay here and cook us. For example, we know that when volcanoes erupt, they release huge amounts of tiny sulphuric dust into the atmosphere that serve as a blanket and measurably cool the planet down. When Mount Tambora blew in 1815, for example, it was known as the “year without summer”. So scientists such as the Nobel Prize-winner Paul Crutzen have suggested we may have to artificially simulate this effect, by spraying sulphur into the atmosphere: in effect, fighting pollution with pollution. The US National Academy of Sciences has gone even further, suggesting that 55,000 small mirrors placed in the upper atmosphere would be enough to counter about half the impact of global warming. So why have greens been reluctant to discuss these solutions? They have a very good reason. All the evidence suggests that, in reality, they cannot work but they sound just plausible enough to join denialism as another hallucinatory excuse to do nothing while the planet boils. Look again at the geo-engineering schemes we’re discussing and you’ll see how. Plans to make the plankton and salps “eat” the carbon for us bump up against an unintended consequence. Too much organic matter sinking all at once triggers the release of methane, the most warming gas of all. What about pumping sulphur into the atmosphere? Ken Caldeira explains: “One of the problems... is that it would destroy the ozone layer, so you might solve the problem of global warming, but then we’d all die of that.” Nor do any of these schemes deal with the other great problem caused by our greenhouse gas emissions. They are making the oceans more acidic, killing off shell and coral formation at the bottom of the food chain. So even if we somehow blunted the global warming effect, the increased carbon in the atmosphere would still kill the oceans and ruin our sources of food. — The Independent |
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An Abyssinian cat from Missouri, named Cinnamon, has just made scientific history. Researchers have largely decoded her DNA, a step that may aid the search for treatments for both feline and human diseases.
The report adds cats to the roughly two dozen mammals whose DNA has been unraveled, a list that includes dogs, chimps, rats, mice, cows and of course, people. Why add cats? They get more than 200 diseases that resemble human illnesses, and knowing the details of their genetic makeup should help in the search for vaccines and treatments, researchers say. The list includes a cat version of AIDS, SARS, diabetes, retinal disease and spina bifida, said Stephen J. O'Brien of the National Cancer Institute. The new work is reported in the November issue of the journal Genome Research by a team including O'Brien and colleague Joan Pontius. It covers about two-thirds of the DNA of Cinnamon, a research cat that lives at the University of Missouri in Columbia; more complete results are expected next year, O'Brien said. Richard Gibbs of the Baylor College of Medicine in Houston, who led a team that decoded the DNA of a monkey called the rhesus macaque, called the new work "a good outline" of cat DNA. Scientists are looking forward to the complete version, which will be useful for making detailed comparisons to the DNA of other animals, he said. — AP
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Hair and nails are formed of dead cells, but both keep growing. Why?
The hair and the nails are made of dead cells. This means that these cells cannot exchange information. That is why you do not feel any pain when you cut your hair or trim your nails. That is the reason that horse's hoofs allow them to run on stony rough surfaces without being hurt or the claws of some animals, or beaks of birds and the horns of deer provide such useful appendages. The hair of a beautiful girl makes her more beautiful and the hair on the body of sheep keeps it insulated from the environment and, when shorn, allows us to make woollen clothes. Invention of the possibility of hair and nails was an intriguing and useful outcome of evolution. But these dead parts must also arise from locations that are alive. In the case of nails, say on our fingers and toes, the insensitive part we see, and sometimes apply nail polish to, is called the nail plate. This plate is coupled to the skin at the bottom. This is called the nail bed. There is a matrix, a hidden part of the nail where the growth takes place. Nails do not grow at the end but from this matrix under the skin of the finger. This is called the cuticle. If you put a mark on your nail with indelible ink, you would see this mark travelling towards the end as time passes. The nail plate, even though made of dead cells, is continuously renewed at the rate of about a millimeter a week. Hair is somewhat similar. The growth is at the follicles under the skin. The dead cells keep being added and the hair grows long. Both, the hair and the nails are made of dense, compacted proteins. I would like to ask you how could the work done in the Space shuttle Columbia help in the treatment of cancer. I am asking this because such a claim was made. I do not know the exact answer, nor am I sure that there is some special magic of working out in space. Maybe what I have just said is not quite correct because the weight-less environment of space does offer the possibility of doing chemistry and biochemistry where the effect of convection is almost completely eliminated. This might allow the possibility of some reactions proceeding with greater ease without the effect of mass differentiation. For a problem like cancer one would try anything. It is true that in space environment of micro-gravity one can grow very large perfect crystals. Several other material science experiments have also been done. One of the techniques of estimating the masses distribution of large protein molecules is to measure the distance they travel in a gel under the influence of an electric field — heavier the molecule slower is its motion. This technique is called electrophoresis. It is clear that this method would work better under conditions where differentiation due to gravitational settling is eliminated. |
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Trends
A tiny speck of pebbles found off the northern coast of Greenland could open up a new front in the looming battle for control of the Arctic and the North Pole.
The best candidate to date for the world's northernmost point of land -- a mythical place sought by explorers for centuries -- was spotted in July during an expedition led by Arctic veteran Dennis Schmitt. California-based Schmitt, best-known for his 2005 discovery of Warming Island off the eastern coast of Greenland, named it Stray Dog West because, he said, it "erred under the ice". It was exposed mainly by shifting pack ice. As Greenland is under Denmark's administration, this scrap of land just 40 meters long could extend Danish territory further north and strengthen Copenhagen's claim on the pole. Its discovery comes as countries around the Arctic Ocean — the United States, Russia, Canada, Denmark, Norway and Iceland -- are rushing to stake out the Polar Basin's seabed, fishing rights and maritime routes. "This little island could have a wide international significance," said Stefan Talmon, professor of international law at Oxford University in Britain. "With the ice melting, more and more of these islands could emerge and play a role in maritime delimitations," he said. Denmark sent an icebreaker to the Arctic this summer to collect geological data in preparation for its claim to extend its shelf beyond the established 200 nautical miles from Greenland's baseline. – Reuters
Troop DNA After two soldiers were killed by the Taliban in Afghanistan over the last month, Australian commanders on Wednesday said voluntary DNA collection would begin as soon as possible for 3,500 Australian soldiers currently deployed overseas "as a result of recent operational experience". "What that'll allow us to do is to enable rapid and positive identification of deceased remains that can't otherwise be identified by traditional forensic methods, such as dental or fingerprint evidence," Australian Defence Force spokesman Brigadier Andrew Nikolic said. Australia, a close U.S. ally, was one of the first nations to commit troops in late 2001 to the U.S.-led war to oust the Taliban and al Qaeda militants from Afghanistan. It also has about 1,500 troops in and around Iraq. — Reuters |
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Australia's military will ask 90,000 soldiers for DNA blood samples to help identify troops as the country prepares for more deaths in Iraq and Afghanistan.