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Science

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.
Science

Submission + - Fate of stars determined by the vacuum around them (physicscentral.com)

Flash Modin writes: Atreyu was right to fear 'The Nothing.' For decades, physicists attempting to unify quantum mechanics and relativity have been finding that the vacuum of space plays a critical role in the universe. From the Dirac sea model of a vacuum as an ocean of negatively charged particles, to the Casimir effect that dictates there will be a force between two or more objects in a vacuum; the subtle, yet critical properties of the vacuum are now needed to fully describe many bizarre phenomena in the cosmos. Now, another possible example of the vacuum's importance has been added. In an upcoming issue of the journal Physical Review Letters, a group of physicists from Brazil show that the vacuum around a relativistic star -a rotating neutron star that requires general relativity to explain its behavior- could determine whether it ejects its mass in a massive explosion, or collapses into a black hole of no escape. The group calls the process "awakening the vacuum" and say it could could provide an important physical test of field theories, because a stable neutron star could confirm or deny what type of field surrounds it. Read the preprint on the physics arXiv.
Science

Submission + - MIT creates an easy to fly iPhone quadcopter (physicscentral.com)

Flash Modin writes: The Humans & Automation Lab (HAL) at MIT has created a quadcopter — or Micro Air Vehicle — that can be flown from an iPhone. The copter can be made to automatically correct for winds or obstacles and can hover at a set altitude to simplify controls; so the user can just plot a point in Google maps and it flies there by itself. Once it reaches the desired point, the copter switches to "nudge controls" so the user can maneuver it to spy on their wife, witness a drug deal or explore the canopy of a rainforest. To prove to the FAA that they should take the technology seriously, the team gave ROTC cadets a three-minute iPhone flying lesson and put the copter in an unfamiliar separate room where they had to pilot it. In the study, nine out of 14 could flawlessly read an eye chart with the copter's camera and identify a specified individual. A similar, but downgraded and commercially available iPhone quadcopter started selling on Amazon last week for $300, but with mixed — and very few — reviews.
Image

Scientists Find a Better Way To Pour Champagne 15

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."
Privacy

Submission + - Is RFID really that scary? (pbs.org)

tcd004 writes: Defcon participant Chris Paget demonstrated his ability to capture RFID data from people hundreds of feet away for the PBS NewsHour. Paget went through the regular laundry list of security concerns over RFID: people can be tracked, their information accessed, their identities comprimised. Not so fast, says Mark Roberti of RFID Journal. Mark challenges Paget to point to a single instance where RFID was successfully used for nefarious purposes. The signals are too weak and the data is too obscure, according to Roberti. So who is right? Has RFID yet lead to a single instance of identity theft, illegal monitoring, or other security compromise?
Idle

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.
Science

Submission + - Physicists say cosmic rays effect length of day (physicscentral.com)

Flash Modin writes: If your Monday is dragging on too long, you might try blaming it on cosmic rays. In a paper published Friday by the journal Geophysical Research Letters, geophysicists from Paris and Moscow propose that the high energy protons and nuclei might have a surprising influence on Earth's length of day. The team claims that a previously noticed relationship between fluctuations in the length of day and the 11-year solar-cycle are actually caused by cosmic rays.The round-about argument is that cosmic rays effect cloud cover, which then changes the atmosphere's energy budget and has a significant enough effect on wind speeds to change the Earth's angular momentum. The net effect is only a few tenths of a millisecond, but the physicists claim the more important implication is in the overall debate over whether cosmic rays could be a cause of climate change by influencing cloud formation.
Science

Submission + - First discovery by an @Home project (sciencemag.org)

pq writes: In a paper published today in Science, astronomers are reporting the discovery of a radio pulsar in data acquired at the world's largest radio telescope and analyzed by hundreds of thousands of volunteers in 192 countries for the Einstein@Home project. This is the first scientific discovery by a distributed computing project, and specific credit is being given to Chris and Helen Colvin of Ames, Iowa, and Daniel Gebhardt of Germany. More at MSNBC etc.
Science

Submission + - Lasers Approach their Ultimate Intensity Limit (physicscentral.com)

Flash Modin writes: Death Star style superlasers? Don't bet on it. High power lasers currently in development appear to be nearing the theoretical laser intensity limit, according to new research set to be published in the journal Physical Review Letters. Ultra-high-energy laser fields can actually convert their light into matter as shown in the late '90s at the Stanford Linear Accelerator (SLAC). This process creates an "avalanche-like electromagnetic cascade" (also known as sparking the vacuum) capable of destroying a laser field. Physicists thought it might be a problem for lasers eventually, but this work indicates the technology is much closer to its limit than researchers believed. A preprint is available on the arXiv.

Submission + - Physics Buzz: Observatory discovers cosmic particl (physicscentral.com)

Flash Modin writes: Physicists from the Pierre Auger Observatory have found that the source of elusive ultra-high-energy cosmic rays is cosmic particle accelerators from stars exploding in the Milky Way. These types of explosions have been seen in other galaxies before, but not our own. This story explains how the discovery was made because the observatory detected far more nuclei than it expected. Nuclei from stellar explosions usually disintegrate very fast, but these nuclei were trapped in a galactic magnetic field where they traveled for millions of years before striking the earth's upper atmosphere.
Science

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.

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