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15 November 2006 NewScientist.com news service DURING the middle ages, the Muslims who fought crusaders with swords of Damascus steel had an edge - a very high-tech one. Their sabres contained carbon nanotubes. From about AD 900 to AD 1750, Damascus sabres were forged from Indian steel called wootz. Peter Paufler of the Technical University of Dresden, Germany, and colleagues studied samples of a 17th-century sword under an electron microscope and found clear evidence of carbon nanotubes and even nanowires. The researchers think that the sophisticated process of forging and annealing the steel formed the nanotubes and the nanowires, and could explain the amazing mechanical properties of the swords (Nature, vol 444, p 286). From issue 2578 of New Scientist magazine, 15 November 2006, page 20 18 November 2006 Zeeya Merali Magazine issue 2578 The world's most wanted particle, the Higgs, may have already appeared under our very noses without anyone noticing THE world's most wanted particle, the Higgs, may have already appeared under our very noses without anyone noticing. The hypothetical Higgs boson, which is thought to give all other particles their mass, was first proposed in the 1960s as part of the standard model of particle physics. Other models known as "supersymmetric" theories, which posit a heavy counterpart for every particle in the standard model, predict the existence of many different Higgs bosons, each with a different mass. It is the lightest one of these that may have already been produced, according to physicist German Valencia at Iowa State University in Ames, Iowa. Valencia and colleagues re-analysed data collected between 1997 and 1999 by the HyperCP experiment at Fermilab in Batavia, Illinois. HyperCP was designed to monitor the decay of exotic particles in order to understand why the universe is filled with matter rather than antimatter. Valencia's team focused on ... The complete article is 662 words long. Magazine issue 2578 Can secular science ever oust religious belief - and should it even try? IT HAD all the fervour of a revivalist meeting. True, there were no hallelujahs, gospel songs or swooning, but there was plenty of preaching, mostly to the converted, and much spontaneous applause for exhortations to follow the path of righteousness. And right there at the forefront of everyone's thoughts was God. Yet this was no religious gathering - quite the opposite. Some of the leading practitioners of modern science, many of them vocal atheists, were gathered last week in La Jolla, California, for a symposium entitled "Beyond belief: Science, religion, reason and survival" hosted by the Science Network, a science-promoting coalition of scientists and media professionals convening at the Salk Institute for Biological Studies. They were there to address three questions. Should science do away with religion? What would science put in religion's place? And can we be good without God? First up to address the initial question was cosmologist ... The complete article is 2369 words long.To continue reading this article, subscribe to New Scientist. Get 4 issues of New Scientist magazine and instant access to all online content for only £2.95 This offer is for delivery in the UK only. Only hungry hens heed the dinner call 00:01 15 November 2006 NewScientist.com news service Emma Young When male chickens come across food, they make a “took, took, took” call to tell the flock – but hens react only if they don’t already know that food is around. This shows that the call triggers other chickens to look for specific information – in this case, whether or not they already know there is food about – and to respond appropriately, researchers claim. This is similar to how human language works, they say. Such “representational” communication has been demonstrated in some primates before, but never in a bird. Critics of the idea that certain animal calls might have similarities with language have suggested, for instance, that the calls might simply be triggering a reflex response, or that researchers might be over-interpreting a call's meaning. “In this work, we have shown that the hens’ response is mediated by a representation of food,” says Chris Evans. He and Linda Evans, both animal behaviourists, studied a type of domestic chicken, called golden Sebrights (Gallus gallus), at Macquarie University in Sydney, Australia. Language-like qualitiesSeveral animal species produce sounds that trigger a particular response among other members of their group. These calls are usually related to the presence of either a predator or food. For example, meerkats produce several different types of alarm call. It takes careful experimentation to show that calls really stand for something specific in the environment, and so have language-like qualities, however. So far, this has been shown only for a few mammals, in particular Diana and Campbell’s monkeys. Evans and Evans played back the golden Sebright food calls to hens, either directly after giving them a few corn kernels to eat or after giving them nothing. The calls only triggered the hens to start peering at the ground to look for food if they had not just received corn. “If you’re on a long drive and you pass a restaurant sign, that could be a salient piece of information. But if, after food has been brought to the table, someone says: ‘There’s food,’ that’s a redundant comment. It’s that kind of contrast,” Chris Evans explains. More work is needed to understand why language-like calls arise in some species but not others, he says, though it does seem that they occur in animals that live in stable social groups surrounded by kin. Journal reference: Biology Letters, DOI: 10.1098/rsbl.2006.0561) 'Evanescent coupling' could power gadgets wirelessly 11:25 15 November 2006 NewScientist.com news service Celeste Biever A phenomenon called "evanescent coupling" could allow electronic gadgets to start charging themselves as soon as their owner walks into their home or office. Researchers have been looking for a way to make a wireless charger for some time. One idea is to use electromagnetic induction – passing an electric current through a coil to create a magnetic field that induces a current in a neighbouring coil. This is the way devices like electric toothbrushes are charged, and has been proposed as the basis of a universal recharger pad before (see One charger pad could power up all gadgets). The snag as far as mobile devices are concerned is that the charger and device must be in close contact with each other for it to work. Alternative schemes - for instance, transmitting electromagnetic waves in all directions to reach any device in a room - would be hugely wasteful. Trapped at source Instead, Marin Soljacic at the Massachusetts Institute of Technology wants to use evanescent coupling, which allows electromagnetic energy "trapped" in a charging device to be tapped by a "drain" mobile device if the two have the same resonant frequency. "The energy is trapped at source, until I bring a device that has the same resonant frequency close to it. Only then can the energy 'tunnel through'," says Soljacic. Crucially, the "charger" only starts powering another device when a compatible gadget comes within range. Soljacic and colleagues Aristeidis Karalis and John Joannopoulos have carried out numerous computer simulations to see if the idea will work. They discovered that a small circuit, consisting of an inductor loop and a capacitor, could be made to resonate at a frequency of 3 to 4 megahertz, allowing it to trap electromagnetic energy without emitting radio waves to its surroundings. Inductor loop In the wireless charger design, alternating current from the mains is converted to this resonant frequency and sent into the circuit. The current travels round the circuit, generating a magnetic field as it passes through the inductor loop and an electric field as it passes through the capacitor. This pulsing magnetic field extends up to 5 metres around the device. The magnetic field created by the wireless charger is relatively weak, meaning it consumes little power. However, if a mobile gadget fitted with a similar circuit, with the same resonant frequency, is brought into the room, the charger's magnetic field induces an electric current in the gadget's inductor loop. This current travels round the mobile device's circuit, constantly switching between electrical and magnetic states, just as in the charger's circuit. As a result, the two circuits start to "resonate" together. This increases the transmission of electromagnetic energy via induction and that energy is used to charge up the gadget. Placing one of these wireless chargers in each room of a home or office could provide coverage throughout the building. Soljacic presented the results at the American Institute of Physics Industrial Physics Forum in San Francisco on 14 November. The team is now trying to develop a prototype device.