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In awe of the big, losing touch with the tiny Online searchers can help strangers make sense of data TRENDS
Psychopaths have distinct brain structure Scientists ‘switch off’ brain cell death in mice
THIS UNIVERSE |
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In awe of the big, losing touch with the tiny Yet 50 years ago, many boys and girls might have enlightened you, says Peter Marren, one of our leading naturalists. For tardigrades and rotifers are microscopic animals found in freshwater bodies, such as ponds, and were the delight of children with microscopes — now, says Marren, virtually a vanished species. Not just children, either. It’s as if, he says, a whole, major part of the natural world has dropped out of our consciousness — microscopic life, the kingdom of the tiny. That’s something he’s an authority on, because two years ago he published Bugs Britannica, a fascinating encyclopaedia of Britain’s invertebrates, the creatures without backbones, which are overwhelmingly insects, but also the very tiny things, such as daphnia or water fleas. Nobody looks at them now, he laments. “Hardly anybody uses a microscope any more. They’re just for specialist activities now, and there aren’t many specialists, either. But half of biodiversity, you need a microscope to see! The teeming hordes of these things, which are everywhere. They’re totally neglected now. Amateur naturalists tend not to bother with them. The sense of wonder you can get through seeing a world you can’t otherwise see — that sort of curiosity seems to have vanished.” He certainly makes that world worth looking at in Bugs Britannica. Tardigrades, for example, are also known as water bears, as they “clamber about on their stumpy legs in an undeniably bear-like manner. “To survive drought, they can shrivel up and dry out — “and in this state, the water bear’s life processes come to a complete stop, and... it can survive almost any conditions.” He instances boiling water, pressure greater than the deepest ocean, irradiation worse than a microwave oven, total asphyxiation, freezing in liquid nitrogen, immersion in toxic chemicals, and, for a clincher, being taken into orbit by the European Space Agency, so that tardigrades are “the first animals to have been exposed to the vacuum of space and unprotected solar radiation, and lived”. A single drop of water revives them. Rotifers are another intriguing part of pond life; many are transparent, so all their internal organs can be seen. “Despite being no bigger than protozoa, a rotifer is a multi-cellular wonder of miniaturisation,” Marren writes. “It has a nervous system as well as a digestive gut, sex organs, a heart and a brain, all packed into a space smaller than a full stop.” Who looks at them now? Modern field guides on pond life, Marren complains, have three or four plates on the microscopic side of it, whereas once they had dozens. “A lot of kids had microscopes then, but kids don’t have microscopes any more. It’s also that ponds are disappearing; every farmer’s field had a pond in the corner, but most of them have gone.
Scientists who miss
the fish for the genes The loss of general familiarity with the microscopic world can, in fact, be seen as part of a bigger picture; the decline of “whole-organism biology”. In the past half century, traditional natural history, the study of animals and plants for themselves, has come to be seen as more and more divorced from the cutting edge of science, indeed, it has come to be despised as merely one step up from stamp collecting; what is now sexy, in scientific terms, is molecular biology, the study of an animal’s genes. I once met a marine biologist from Plymouth who complained that he knew scientists who could tell you everything you wanted to know about the genomes of fish, but if you handed them an unusual fish species brought back by a trawler, they wouldn’t have a clue what it was.
— The Independent |
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Online searchers can help strangers make sense of data PEOPLE who have already processed online information to make sense of a subject can help strangers facing similar tasks. This process of distributed sense making, say researchers from Carnegie Mellon University and Microsoft, could save time and result in a better understanding of the information needed for whatever goal users might have. They could be planning a vacation, gathering information about a serious disease or trying to decide what product to buy, according to a Carnegie Mellon statement. Researchers explored the use
of digital knowledge maps, a means of representing the thought processes used to make sense of information gathered from the Web. For instance, two people looking to start a garden might live in different climates or settings, so the types of seeds they might plant could be different, but each would benefit from elements such as “design ideas”, “how to” and so on. When participants used a knowledge map that had been created and improved upon by several previous users, they reported that the quality of their own work was better than when they started from scratch or used a newly created knowledge map. “Collectively, people spend more than 70 billion hours a year trying to make sense of information they have gathered online,” said Aniket Kittur, Assistant Professor in Carnegie Mellon's Human-Computer Interaction Institute, who led the study. “Yet in most cases, when someone finishes a project, that work is essentially lost, benefiting no one else and perhaps even being forgotten by that person. If we could somehow share those efforts, however, all of us might learn faster.” These findings were presented at CHI 2012, the Conference on Human Factors in Computing Systems, in Austin, Texas, US.
— IANS |
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Psychopaths have distinct brain structure LONDON: Scientists who scanned the brains of men convicted of murder, rape and violent assaults have found the strongest evidence yet that psychopaths have structural abnormalities in their brains. The researchers, based at King's College London's Institute of Psychiatry, said the differences in psychopaths' brains mark them out even from other violent criminals with anti-social personality disorders (ASPD), and from healthy non-offenders.
Scientists ‘switch off’ brain cell death in mice LONDON: Scientists have figured out how to stop brain cell death in mice with brain disease and say their discovery deepens understanding of the mechanisms of human neurodegenerative diseases such as Alzheimer's and Parkinson's. British researchers writing in the journal Nature said they had found a major pathway leading to brain cell death in mice with prion disease, the mouse equivalent of Creutzfeld-Jacob Disease (CJD).
— Reuters |
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THIS UNIVERSE Air contains approximately 78 per cent nitrogen, 21 per cent oxygen and 1 per cent carbon dioxide and other gases. Human beings inhale oxygen and exhale carbon dioxide, whereas plants absorb carbon dioxide that we exhale, and release oxygen back into the atmosphere. As a result, carbon dioxide and oxygen never finish in the atmosphere. Now coming to nitrogen, it is used by plants, which it gets from manure and fertilisers we mix in the soil; maybe nitrogen is used somewhere else also. I want to know what gives nitrogen back that it never finishes in the atmosphere? Your question is very interesting. But you know that nitrogen is more abundant in the atmosphere. Furthermore, the nitrogen absorbed by plants and crops does not stay permanently absorbed. Plants are also recycled and whatever is absorbed can also be returned to the atmosphere in one form or another after some time. How were the alpha particles rebounding at 180 degrees in the scattering experiment of Rutherford detected? I can understand the detection of scattering through any angle other than 180 degrees through scintillations and telescope. But how were the particles rebounding in the firing direction (180 degrees) detected? You should be able to easily comprehend a tennis or a cricket ball bouncing back at a 180-degree angle after hitting a wall. This is what can happen to an alpha particle hitting a very heavy nucleus. Readers wanting to ask Prof Yash Pal a question can e-mail him at palyash.pal@gmail.com |
ASK your child what a tyrannosaurus is, or a velociraptor, and you’ll probably get an intelligible answer. Movies have made dinosaurs familiar to millions. But ask them what a rotifer is, or a tardigrade, and you’ll get a blank stare.