Accelerator On a Chip: Technology Could Spawn New Generations of Smaller, Less Expensive Devices for Science, Medicine

In an advance that could dramatically shrink particle accelerators for science and medicine, researchers used a laser to accelerate electrons at a rate 10 times higher than conventional technology in a nanostructured glass chip smaller than a grain of rice.

ScienceDaily: Mobile Computing News

ScienceDaily: Mobile Computing News

NASA Curiosity Rover Detects No Methane On Mars.

The roving laboratory performed extensive tests to search for traces of Martian methane. Whether the Martian atmosphere contains traces of the gas has been a question of high interest for years because methane could be a potential sign of life, although it also can be produced without biology. "This important result will help direct our efforts to examine the possibility of life on Mars," said Michael Meyer, NASA's lead scientist for Mars exploration. "It reduces the probability of current methane-producing Martian microbes, but this addresses only one type of microbial metabolism. As we know, there are many types of terrestrial microbes that don't generate methane." Curiosity analyzed samples of the Martian atmosphere for methane six times from October 2012 through June and detected none. Given the sensitivity of the instrument used, the Tunable Laser Spectrometer, and not detecting the gas, scientists calculate the amount of methane in the Martian atmosphere today must be no more than 1.3 parts per billion. That is about one-sixth as much as some earlier estimates. Details of the findings appear in the Thursday edition of Science Express. "It would have been exciting to find methane, but we have high confidence in our measurements, and the progress in expanding knowledge is what's really important," said the report's lead author, Chris Webster of NASA's Jet Propulsion Laboratory in Pasadena, Calif. "We measured repeatedly from Martian spring to late summer, but with no detection of methane." Webster is the lead scientist for spectrometer, which is part of Curiosity's Sample Analysis at Mars (SAM) laboratory. It can be tuned specifically for detection of trace methane. The laboratory also can concentrate any methane to increase the gas' ability to be detected. The rover team will use this method to check for methane at concentrations well below 1 part per billion. Methane, the most abundant hydrocarbon in our solar system, has one carbon atom bound to four hydrogen atoms in each molecule. Previous reports of localized methane concentrations up to 45 parts per billion on Mars, which sparked interest in the possibility of a biological source on Mars, were based on observations from Earth and from orbit around Mars. However, the measurements from Curiosity are not consistent with such concentrations, even if the methane had dispersed globally. "There's no known way for methane to disappear quickly from the atmosphere," said one of the paper's co-authors, Sushil Atreya of the University of Michigan, Ann Arbor. "Methane is persistent. It would last for hundreds of years in the Martian atmosphere. Without a way to take it out of the atmosphere quicker, our measurements indicate there cannot be much methane being put into the atmosphere by any mechanism, whether biology, geology, or by ultraviolet degradation of organics delivered by the fall of meteorites or interplanetary dust particles." The highest concentration of methane that could be present without being detected by Curiosity's measurements so far would amount to no more than 10 to 20 tons per year of methane entering the Martian atmosphere, Atreya estimated. That is about 50 million times less than the rate of methane entering Earth's atmosphere. Curiosity landed inside Gale Crater on Mars in August 2012 and is investigating evidence about habitable environments there. JPL manages the mission and built the rover for NASA's Science Mission Directorate in Washington. The rover's Sample Analysis at Mars suite of instruments was developed at NASA's Goddard Space Flight Center in Greenbelt, Md., with instrument contributions from Goddard, JPL and the University of Paris in France.

Brain Eatting Amoeba.

Brain-eating amoeba rattles nerves in Louisiana after being found in local water.NEW ORLEANS (AP) — A deadly, brain- eating amoeba has been found in the water supply of a Louisiana community near New Orleans, scaring residents and sending officials on the hunt for its source. Experts say the only danger is to people who manage to get the microscopic organism way up their noses. Its only entry to the brain is through tiny openings in a bone about level with the top of the eyeball, said Dr. Raoult Ratard, Louisiana's state epidemiologist. The state Department of Health and Hospitals on Thursday tried to dispel common "myths and rumors" about the amoeba Naegleria fowleri — starting with the notion that the St. Bernard Parish water isn't safe to drink. The worries began Sept. 12, when the state health department reported that water in the Violet and Arabi communities outside New Orleans tested positive for the amoeba that killed a 4-year-old Mississippi boy in August after he visited St. Bernard Parish. Jonathan Yoder, an epidemiologist in the Center for Disease Control and Prevention's waterborne disease prevention branch, said Naegleria has never before been found in water treated by a U.S. water system. There have been 132 documented infections from the amoeba since 1962, almost all of them fatal, health officials say. Both of Louisiana's 2011 infections were of people who used tap water to flush out their sinuses. In those cases, Yoder said the amoeba was found in the house's hot water system but not in municipal water or water coming from the home's cold water tap. But still, people worry. "Nobody's washing their faces in the showers anymore. Nobody's drinking the water," Angela Miller said Thursday. "My neighbor has a pool that they have emptied. And they have no water in there now until this matter is cleared up." That's not necessary, experts say. Stomach acids, boiling and chlorine all will kill the amoeba. Investigators may never know just how Naegleria got into the pipes. Copyright (2013) Associated Press. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.