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Why French red is best for the heart
Enigmatic relic was Quantum computers? Don’t hold your breath eclipse calculator
RIEN VAN DE WEIJGAERT
www.newscientist.com
061202_N_p16_p17_Inbriefs.indd 17
QUANTUM computing will never work. At least, that’s the view of one physicist who thinks that unavoidable noise will always stand in its way. In theory, a quantum computer could be far more powerful than any existing device. Making it work, however, means protecting the quantum particles used in its calculations from the disrupting noise of the outside world. To date, this has been achieved only for a few particles for fractions of a second. A useful device would have to be noiseless
for far longer, and use hundreds or thousands of particles. Michael Dyakonov of the University of Montpellier in France believes this feat is akin to achieving perpetual motion. It has been assumed till now that errors caused by noise can be fixed. In reality, Dyakonov argues, such errors would grow far too rapidly with the number of particles, making correction impractical. What’s more, he says, correction schemes make unproven assumptions: for example, that the various
errors introduced by imperfect devices will be independent of one another, and so largely cancel each other out. “I have serious doubts about the possibility of large-scale quantum computations,” he says (www. arxiv.org/quant-ph/0610117). Others think Dyakonov has got it wrong. “It is true that the quantum computing community should be cautiously optimistic, rather than confident,” says Andrew Steane of the University of Oxford. “But his arguments are largely misleading.”
Why French red is best for the heart
worms and fish, but Corder found that its levels in red wine were so low that it had no effect on blood vessels at all. Procyanidins, however, suppressed the synthesis of a peptide called endothelin-1 that constricts blood vessels. “With resveratrol you’d need to drink 1000 litres of red wine or so to have any chance of affecting longevity,” says Corder. “But procyanidins are so potent that drinking just one glass a day would have an effect.” The team also compared the procyanidin content of wines from different regions. Wines from southwest France and Sardinia had between two and four times as much procyanidins as other red wines. Corder says this is because traditional winemaking techniques are still in use there.
Calling a species ‘rare’ seals its fate MERELY declaring that a species is endangered could be enough to sign its death warrant, thanks to the human penchant for collecting rarities. Economists have thought that over-exploitation is unlikely to drive species to extinction, because numbers will dwindle to the point where it becomes unprofitable to continue harvesting them. However, that view ignores the possibility that enthusiasts may be willing to pay exorbitant prices for rare specimens. This is just the incentive unscrupulous hunters need to track down the last few individuals, say Franck Courchamp and colleagues at the University of Paris-South in Orsay, France (PLoS Biology, vol 4, e415). For example, animals command much higher prices if they are listed as endangered. Bahaba taipingensis, a species of fish nearing extinction because of its use in Chinese traditional medicine, is now so coveted that a single swimbladder can sell for as much as $64,000. In the 1990s, more than 100 boats continued to search for the fish despite total annual catches of fewer than half a dozen individuals.
CHRISTOHE LEPETIT/BTOOB/EYEVINE
THE mystery over the original purpose of a sophisticated geared calculator built in the 2nd century BC has been solved. The so-called Antikythera mechanism was found in 1902 by sponge divers exploring a shipwreck off the Greek island of the same name, but its exact use has puzzled scientists ever since. The relic consists of numerous fragments, including brass gears embedded in thick mineral encrustations. The device is thought to have once been housed in a wooden box about the size of a carriage clock and is more complex by far than any other machine known to have existed on the planet for the following 1000 years. Now a team led by Mike Edmunds at Cardiff University in Wales has shown that the Antikythera mechanism was designed to predict eclipses from the relative positions of the Earth, moon and sun. Edmunds’s team used a CT scanner to map out the gear trains within the mineralencrusted fragments and to determine how they fit together. The team also found fragments of previously hidden text. “The real significance of this is just how sophisticated the device was – much more complex than a modern wristwatch,” says Edmunds. “It is beautifully designed.” The team is constructing a virtual model of the mechanism, which they hope to have complete within a few months (Nature, DOI: 10.1038/ nature05357).
IF YOU’RE toasting to a long life, opt for a glass of red from south-west France. Red wines from this region have the highest levels of procyanidins – the compounds in grape seeds we now know are responsible for making red wine good for your heart. Roger Corder at Queen Mary’s School of Medicine in London and his colleagues used cultured endothelial cells from blood vessels to identify which component of red wine had the greatest effect on blood vessel dilation. Previous studies have shown that resveratrol, found in the skin of red grapes, extends the life of yeast, flies,
2 December 2006 | NewScientist | 17
27/11/06 2:49:55 pm
RIEN VAN DE WEIJGAERT
www.newscientist.com
061202_N_p16_p17_Inbriefs.indd 17
QUANTUM computing will never work. At least, that’s the view of one physicist who thinks that unavoidable noise will always stand in its way. In theory, a quantum computer could be far more powerful than any existing device. Making it work, however, means protecting the quantum particles used in its calculations from the disrupting noise of the outside world. To date, this has been achieved only for a few particles for fractions of a second. A useful device would have to be noiseless
for far longer, and use hundreds or thousands of particles. Michael Dyakonov of the University of Montpellier in France believes this feat is akin to achieving perpetual motion. It has been assumed till now that errors caused by noise can be fixed. In reality, Dyakonov argues, such errors would grow far too rapidly with the number of particles, making correction impractical. What’s more, he says, correction schemes make unproven assumptions: for example, that the various
errors introduced by imperfect devices will be independent of one another, and so largely cancel each other out. “I have serious doubts about the possibility of large-scale quantum computations,” he says (www. arxiv.org/quant-ph/0610117). Others think Dyakonov has got it wrong. “It is true that the quantum computing community should be cautiously optimistic, rather than confident,” says Andrew Steane of the University of Oxford. “But his arguments are largely misleading.”
Why French red is best for the heart
worms and fish, but Corder found that its levels in red wine were so low that it had no effect on blood vessels at all. Procyanidins, however, suppressed the synthesis of a peptide called endothelin-1 that constricts blood vessels. “With resveratrol you’d need to drink 1000 litres of red wine or so to have any chance of affecting longevity,” says Corder. “But procyanidins are so potent that drinking just one glass a day would have an effect.” The team also compared the procyanidin content of wines from different regions. Wines from southwest France and Sardinia had between two and four times as much procyanidins as other red wines. Corder says this is because traditional winemaking techniques are still in use there.
Calling a species ‘rare’ seals its fate MERELY declaring that a species is endangered could be enough to sign its death warrant, thanks to the human penchant for collecting rarities. Economists have thought that over-exploitation is unlikely to drive species to extinction, because numbers will dwindle to the point where it becomes unprofitable to continue harvesting them. However, that view ignores the possibility that enthusiasts may be willing to pay exorbitant prices for rare specimens. This is just the incentive unscrupulous hunters need to track down the last few individuals, say Franck Courchamp and colleagues at the University of Paris-South in Orsay, France (PLoS Biology, vol 4, e415). For example, animals command much higher prices if they are listed as endangered. Bahaba taipingensis, a species of fish nearing extinction because of its use in Chinese traditional medicine, is now so coveted that a single swimbladder can sell for as much as $64,000. In the 1990s, more than 100 boats continued to search for the fish despite total annual catches of fewer than half a dozen individuals.
CHRISTOHE LEPETIT/BTOOB/EYEVINE
THE mystery over the original purpose of a sophisticated geared calculator built in the 2nd century BC has been solved. The so-called Antikythera mechanism was found in 1902 by sponge divers exploring a shipwreck off the Greek island of the same name, but its exact use has puzzled scientists ever since. The relic consists of numerous fragments, including brass gears embedded in thick mineral encrustations. The device is thought to have once been housed in a wooden box about the size of a carriage clock and is more complex by far than any other machine known to have existed on the planet for the following 1000 years. Now a team led by Mike Edmunds at Cardiff University in Wales has shown that the Antikythera mechanism was designed to predict eclipses from the relative positions of the Earth, moon and sun. Edmunds’s team used a CT scanner to map out the gear trains within the mineralencrusted fragments and to determine how they fit together. The team also found fragments of previously hidden text. “The real significance of this is just how sophisticated the device was – much more complex than a modern wristwatch,” says Edmunds. “It is beautifully designed.” The team is constructing a virtual model of the mechanism, which they hope to have complete within a few months (Nature, DOI: 10.1038/ nature05357).
IF YOU’RE toasting to a long life, opt for a glass of red from south-west France. Red wines from this region have the highest levels of procyanidins – the compounds in grape seeds we now know are responsible for making red wine good for your heart. Roger Corder at Queen Mary’s School of Medicine in London and his colleagues used cultured endothelial cells from blood vessels to identify which component of red wine had the greatest effect on blood vessel dilation. Previous studies have shown that resveratrol, found in the skin of red grapes, extends the life of yeast, flies,
2 December 2006 | NewScientist | 17
27/11/06 2:49:55 pm