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Submission + - Graphene conducts electricity ten times better than expected (nature.com) 1

ananyo writes: Physicists have produced nanoribbons of graphene — the single-atom-thick carbon — that conduct electrons better than theory predicted even for the most idealized form of the material. The finding could help graphene realize its promise in high-end electronics, where researchers have long hoped it could outperform traditional materials such as silicon.
In graphene, electrons can move faster than in any other material at room temperature. But techniques that cut sheets of graphene into the narrow ribbons needed to form wires of a nano-scale circuit leave ragged edges, which disrupt the electron flow. Now a team led by physicist Walt de Heer at the Georgia Institute of Technology in Atlanta has made ribbons that conduct electric charges for more than 10 micrometres without meeting resistance — 1,000 times farther than in typical graphene nanoribbons. The ribbons made by de Heer's team in fact conduct electrons ten times better than standard theories of electron transport they should, say the authors.

Submission + - Experiments Reveal That Deformed Rubber Sheet Is Not Like Spacetime (medium.com) 1

KentuckyFC writes: General relativity is mathematically challenging and yet widely appreciated by the public. This state of affairs is almost entirely the result of one the most famous analogies in science: that the warping of spacetime to produce gravity is like the deformation of a rubber sheet by a central mass. Now physicists have tested this idea theoretically and experimentally and say it doesn't hold water. It turns out that a marble rolling on deformed rubber sheet does not follow the same trajectory as a planet orbiting a star and that the marble's equations of motion lead to a strangely twisted version of Kepler's third law of planetary motion. And experiments with a real marble rolling on a spandex sheet show that the mass of the sheet itself creates a distortion that further complicates matters. Indeed, the physicists say that a rubber sheet deformed by a central mass can never produce the same motion of planet orbiting a star in spacetime. So the analogy is fundamentally flawed. Shame!

Submission + - Australian team working on engines without piston rings

JabrTheHut writes: An Australian team is seeking funding for bringing an interesting idea to market: cylinder engines without piston rings. The idea is to use small groves that create a pressure wave that acts as a seal for the piston, eliminating the piston ring and the associated friction. Engines will then run cooler, can be more energy efficient and may even burn fuel more efficiently, at least according to the story at http://www.motoring.com.au/news/2013/aussie-invention-eliminates-piston-rings-40773. Mind you, they haven't even built a working prototype yet. If it works I'd love to fit this into an older car...

Submission + - CES: Laser headlights edge closer to real-world highways

jeffb (2.718) writes: Audi will display laser-headlight technology on a concept car at the 2014 Consumer Electronics Show, joining BMW, whose plug-in hybrid should reach production in 2014. A November article on optics.org describes the technology in more detail. This approach does not scan or project a "laser beam" from the car; instead, it uses blue lasers as highly efficient light emitters, and focuses their light onto a yellow phosphor, producing an extremely intense and compact white light source and then forming that light into a conventional headlamp beam. The beam isn't coherent or point-sourced, so it won't produce the "speckling" interference effects of direct laser illumination, and it won't pose specular-reflection hazards. It's just a very bright and very well-controlled beam of normal white light.

HOWEVER, if multi-watt blue laser emitters go into mass production for the automotive market, it's likely to drive down their prices in other applications — for example, grey-market multi-watt "laser pointers". If you're looking for a tool to burn holes in the tires of drivers who offend you, this technology may indirectly help to fulfill your wish.

Submission + - Source code for 22nd IOCCC winners has been released (ioccc.org)

An anonymous reader writes: The source code for the 22nd IOCCC winners has finally been released. Many entries exploited bugs in the size check program, making the 2013 entries possibly the most featureful submissions ever.

Submission + - Kernel DBus Now Boots With Systemd On Fedora (phoronix.com)

An anonymous reader writes: Red Hat developers doing some holiday hacking have managed to get a bootable system with systemd + KDBUS on Fedora 20. KDBUS is a new DBus implementation for the Linux kernel that provides greater security and better performance than the DBus daemon in user-space. Systemd in turn interfaces with KDBUS for user-space interaction. Testing was done on Fedora 20 but the systemd + KDBUS configuration should work on any modern distribution when using the newest code.

Submission + - Google Makes it Harder for Marketers to Collect User Data

cagraham writes: In a seemingly minor update, Google announced that all Gmail images will now be cached on their own servers, before being displayed to users. This means that users won't have to click to download images in every email now — they'll just automatically be shown. For marketers, however, the change has serious implications. Because each user won't download the images from a third-party server, marketers won't be able to see open-rates, log IP addresses, or gather information on user location and browser type. Google says the changes are intended to enhance user privacy and security.

Submission + - Create your own Bullet Time camera rig with Raspberry Pi (muktware.com)

sfcrazy writes: A team of extremely creative people have created a really inexpensive bullet time set-up using Raspberry Pis — and the whole set-up costs less than a professional DSLR camera. The rig looks more like the LHC at CERN using nearly half a kilometre of network cables, 48 Raspberry Pis fitted with cameras and PiFace Control. The rig worked perfectly — in terms of doing what a bullet time set-up should do. Raspberry Pis achieved the Hollywood's 'frozen time' affect at a much lesser cost.

Submission + - Diet Drugs Work: Why Won't Doctors Prescribe Them?

Hugh Pickens DOT Com writes: Suzanne Koven, a primary-care doctor at Massachusetts General Hospital in Boston, writes in the New Yorker that the FDA has currently approved four drugs that will help patients lose weight but few primary-care physicians will prescribe them. Qsymia and Belviq work by suppressing appetite and by increasing metabolism, and by other mechanisms that are not yet fully understood. "But I’ve never prescribed diet drugs, and few doctors in my primary-care practice have, either," writes Koven and the problem is that, while specialists who study obesity view it as a chronic but treatable disease, primary-care physicians are not fully convinced that they should be treating obesity at all. The inauspicious history of diet drugs no doubt contributes to doctors’ reluctance to prescribe them. In the nineteen-forties, when doctors began prescribing amphetamines for weight loss, rates of addiction soared. But in addition, George Bray thinks that socioeconomic factors play into physicians’ lack of enthusiasm for treating obesity because obesity is, disproportionately, a disease of poverty. Because of this association, many erroneously see obesity as more of a social condition than a medical one, a condition that simply requires people to try harder. Louis Aronne likens the current attitude toward obesity to the prevailing attitude toward mental illness years ago and remembers, during his medical training, seeing psychotic patients warehoused and sedated, treated as less than human. "What the hell was I thinking when I didn’t do anything to help them? How wrong could I have been?’" Specialists are now developing programs to aid primary-care physicians in treating obesity more aggressively and effectively but first primary-care physicians will have to want to treat it. “Whether you call it a disease or not is not so germane," says Lee M. Kaplan. "The root problem is that whatever you call it, nobody’s taking it seriously enough.”

Submission + - Could IBM's Watson Put Google in Jeopardy? 1

theodp writes: Over at Wired, Vashant Dhar poses a provocative question: What If IBM’s Watson Dethroned the King of Search? "If IBM did search," Dhar writes, "Watson would do much better than Google on the tough problems and they could still resort to a simple PageRank-like algorithm as a last resort. Which means there would be no reason for anyone to start their searches on Google. All the search traffic that makes Google seemingly invincible now could begin to shrink over time." Mixing supercomputers with a scalable architecture of massive amounts of simple processors and storage, Dhar surmises, would provide a formidable combination of a machine that can remember, know, and think. And because the costs of switching from Google search would not be prohibitive for most, the company is much more vulnerable to disruption. "The only question," Dhar concludes, "is whether it [IBM] wants to try and dethrone Google from its perch. That’s one answer Watson can’t provide."

Submission + - Ask Slashdot: What's the best way to work on projects while travelling?

An anonymous reader writes: I really want to go travel the world with the money I've saved up at my day job, but I also want to grow as a developer in the process. This is a long-term engagement: 2-3 years or more depending on whether my software is successful. I'll probably be hopping from hostel to hostel at first, with a few weeks at each. How do I find a good work environment in these conditions? Do hostels generally have quiet areas where work could be done? Is it OK to get out your laptop and spend the day in a cafe in Europe, assuming you keep buying drinks? What about hackerspaces — are those common on the other side of the globe? (Apartments are an option for later on, but I'm concerned about losing the social atmosphere that's built in with the hostel lifestyle.)

I've never done anything like this before, but I'm really excited about the idea! Any advice would be greatly appreciated.

Submission + - Why We'll Never Meet Aliens (blogspot.com)

iggychaos writes: The idea that aliens will come visit us is fundamentally flawed. Paul Tyma ponders the technology that would be required for such an event and examines how evolution of that technology would preclude any reason to actually make the trip.

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