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Submission Summary: 0 pending, 27 declined, 24 accepted (51 total, 47.06% accepted)


Submission + - Fine structure constant may not be so constant (physicscentral.com)

BuzzSkyline writes: "Physics Buzz is reporting, "Just weeks after speeding neutrinos seem to have broken the speed of light, another universal law, the fine structure constant might be about to crumble." Astronomical observations seem to indicate that the constant, which controls the strength of electromagnetic interactions, is different in distant parts of the universe. Among other things, the paper may explain why the laws of physics in our corner of the universe seem to be finely tuned to support life. The research is so controversial that it took over a year to go from submission to publication in Physical Review Letters, rather than the weeks typical of most other papers appearing in the peer-reviewed journal."

Submission + - Powerful magnets could prevent heart attacks (physicscentral.com)

BuzzSkyline writes: "A few minutes in a high magnetic field (1.3 Tesla) is enough to thin blood by 30%, potentially leading to a new drug-free therapy to prevent heart attacks. The powerful field causes blood cells to line up in chains that flow much more easily than randomly-scattered individual cells, according to research scheduled to appear this month in the journal Physical Review E."

Submission + - Breaking into the Supercollider (physicscentral.com)

BuzzSkyline writes: "A group of physicists went AWOL from the American Physical Society conference in Dallas this week to explore the ruins of the nearby Superconducting Super Collider. The SSC was to be the world's largest and most ambitious physics experiment. It would have been bigger than the LHC and run at triple the energy. But the budget ran out of control and the project was scrapped in 1993."

Submission + - Walking Bacteria (physicscentral.com)

BuzzSkyline writes: Students at UCLA have made the startling discovery that some bacteria can walk on surfaces using structures called Type IV pili as legs. Previously, it was generally believed that bacteria needed to be embedded in fluids to move around significantly. The revelation helps explain the spread of biofilms, and shows why some some bacteria can be particularly dangerous. The professor overseeing the research believes that disabling or lopping off the bacteria legs may offer a novel route to fight infections caused by walking bacteria. The article describing the research has some pretty freaky video of bacteria standing up on one end and walking away.

Submission + - Scientists Find a Better Way to Pour Champagne (physicscentral.com)

BuzzSkyline writes: It's better to pour Champagne the way a good bartender draws a beer, by running it down the inside surface of the glass. The revelation, which appears in July 2010 issue of the Journal of Agricultural and Food Chemistry, flies in the face of age-old French traditions, which require the bubbly to be poured in a stream that free-falls straight down the center of a champagne flute. By using infrared thermography to image the carbon dioxide that escapes over the rim of a Champagne glass for various style pours, the researchers proved that the gentler, beer-like technique allows the wine to retain more of the dissolved gas that is critical to the whole Champagne experience.

Submission + - World'sTiniest Radiometer to Power Medical Scanner (physicscentral.com)

BuzzSkyline writes: University of Texas physicists have built the world's smallest radiometer. The minuscule radiometer is only 2 millimeters across and operates on the same principles as the common light-driven toy, which consists of spinning black and white vanes in a partially evacuated bulb. The researchers attached a mirror to their tiny radiometer and used it to rapidly scan a laser beam. Their hope is that they will be able to incorporate the radiometer into catheters to drive scanners that produce medical images of the interiors of blood vessels and organs. The devices would replace micromotors in conventional catheter-based scanners, eliminating the need to run potentially risky electrical currents into the body.

Submission + - Body Heat Energy Generation (physicscentral.com)

BuzzSkyline writes: Researchers in Belgium have developed devices to harvest the waste heat our bodies throw off in order to convert it to electricity to run devices such as a wristband blood oxygen sensor and an electrocardiogram shirt. As a side benefit, the power sources help cool you down and keep you looking cool, all while running sundry micropower devices. In fact, the researchers mention that the energy harvesting head band works so well that it can get uncomfortably cold. In that case, they say, "This problem is solved in exactly the same way as someone solves it on the body level in cold weather: a headgear should be worn on top of the system to limit the heat flow and make it comfortable." But it would be such a shame to cover up the golden heat-harvesting headband with a hat. The research was published last month in the Journal of Renewable and Sustainable Energy.

Submission + - The End of Moore's Law (insidescience.org)

BuzzSkyline writes: Physicists have found that there is an ultimate limit to the speed of calculations, regardless of any improvements in technology. According to the researchers who found the computation limit, the bound "poses an absolute law of nature, just like the speed of light." While many experts expect technological limits to kick in eventually, engineers always seems to find ways around such roadblocks. If the physicists are right, though, no technology could ever beat the ultimate limit they've calculated. At the current Moore's Law pace, computational speeds will hit the wall in 75 years. A paper describing the analysis, which relies on thermodynamics, quantum mechanics and information theory, appeared in a recent issue of Physical Review Letters.

Submission + - Zombie Avoidance (insidescience.org)

BuzzSkyline writes: "Last month, math students published a model of a zombie infestation that explained how the disease might spread. A new physics paper offers help for the more immediate problem — how to avoid being eaten. The paper, which recently appeared in the journal Physical Review E, considers where best to hide when being pursued by zombie-like predatory "random walkers." Although the researchers weren't thinking of zombies when they wrote the paper, the abstract describes the research as focusing on "the survival probability of immobile targets annihilated by a population of random walkers." (Sounds like a zombie movie premise to me.) The bottom line is you're better off the more labyrinth-like your hiding place is. So take a lesson from Dawn of the Dead, and hunker down in the mall, not in a farmhouse (as in Night of the Living Dead)."

Submission + - Most detailed photos of an atom yet (insidescience.org) 1

BuzzSkyline writes: Ukrainian researchers have managed to take pictures of atoms that reveal structure of the electron clouds surrounding carbon nuclei in unprecedented detail. Although the images offer no surprises (they look much like the sketches of electron orbitals included in high school science texts), this is the first time that anyone has directly imaged atoms at this level, rather than inferring the structure of the orbitals from indirect measurements such as electron or x-ray interferometry.

Submission + - Lego Blocks Simulate Microfluidic Filters (physicscentral.com)

BuzzSkyline writes: "Researchers at Johns Hopkins University are playing with Lego blocks to discover how arrays of nanoscopic obstacles could sort cells and other tiny particles by size. Ball bearings dropped through an array of Lego pieces submerged in glycerin serve as an analogue of the tiny systems, with bearings of different sizes taking different paths through the array. A research paper describing the Lego research recently appeared in the journal Physical Review Letters."
The Military

Submission + - Military Helmet Design Contributes to Brain Damage (physicscentral.com)

BuzzSkyline writes: "Improvements in helmets have helped modern soldiers survive bullets and blasts that would have killed them in past wars. But increasing numbers of soldiers are suffering long lasting brain damage from explosions, partly as a result of what appears to be a flaw in helmet designs. Although the blast itself may not accelerate the brain inside a soldier's head enough to cause injury, shockwaves that make it through the space between a helmet and a soldier's head can cause the skull to flex, leading to ripples in the skull that can create damaging pressures in the brain. Simulations that relied on "code originally designed to simulate how a detonated weapon rattles a building or tank" could lead to new helmets that reduce the traumatic brain injuries that many soldiers suffer as a result of improvised explosive devices and other moderate-sized blasts. The research is due to be published in Physical Review Letters, but a preprint is currently available on the Physics ArXiv."

Submission + - Obstacles Near Emergency Exits Speed Evacuation (physicscentral.com)

BuzzSkyline writes: "Despite fire codes that require emergency exits be clear of obstacles, some types of obstacles actually speed evacuation. The counterintuitive conclusion resulted from a series of experiments performed at a TV studio in Japan. Researchers from the University of Tokyo asked 50 volunteers to exit the studio through a narrow door. Video tapes of the experiments show that that people made it out quickest when a pole was placed about 30 degrees to one side of the exit. The lead researcher believes an obstacle reduces jamming and friction among people in crowds by decreasing conflicts as the crowd presses toward the exit. A paper describing the researcher is schedule to appear in the journal Physical Review E in September, but a preprint is available on the Physics Arxiv."
Social Networks

Submission + - Email Rumor Tipping Point (physicscentral.com)

BuzzSkyline writes: "Some email rumors and hoaxes spread like wildfire and then peter out quickly. Others spread slowly but keep making the rounds for years. So what's the difference? According to an experiment conducted by researchers at the University Carlos III of Madrid working together with IBM's European e-marketing division, it depends on whether the rumor crosses the gossip tipping point. The experiment, which is being reported in Physical Review Letters, consisted of a marketing campaign that awarded a raffle ticket for a laptop to people who referred friends to a newsletter subscription. The researchers found that as long as the number of hyper-connected users who pass on emails immediately exceeded a critical value (i.e. the tipping point), the campaign message goes viral. Otherwise, the message ends up as a slow moving, long-lasting rumor that is primarily spread by people who let messages sit in their inboxes for a long time before passing them on. The experiment is unusual for this sort of research — most papers dealing with information diffusion in social networks are purely theoretical."

Submission + - @sshole Drivers Reduce Traffic Jams (physicscentral.com) 3

BuzzSkyline writes: "Traffic jams are minimized if a significant fraction of drivers break the rules by doing things like passing on the wrong side or changing lanes too close to an intersection. The insight comes from a cellular automata study published this month in the journal Physical Review E. In effect, people who disregard the rules help to break up the groups that form as rule-followers clump together. The risk of jamming is lower if all people obey the rules than if they all disobey them, according to the analysis, but jamming risk is lowest when about 40 percent of people drive like jerks."

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