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The ability of NASA's Mars Reconnaissance Orbiter to continue charting the locations of these hidden glaciers and ice-filled valleys -- first confirmed by radar two years ago -- adds clues about how these deposits may have been left as remnants when regional ice sheets retreated. The subsurface ice deposits extend for hundreds of kilometers, or miles, in the rugged region called Deuteronilus Mensae, about halfway from the equator to the Martian north pole. Jeffrey Plaut of NASA's Jet Propulsion Laboratory, Pasadena, Calif., and colleagues prepared a map of the region's confirmed ice for presentation at this week's 41st Lunar and Planetary Science Conference near Houston. The Shallow Radar instrument on the orbiter has obtained more than 250 observations of the study area, which is about the size of California. "We have mapped the whole area with a high density of coverage," Plaut said. "These are not isolated features. In this area, the radar is detecting thick subsurface ice in many locations." The common locations are around the bases of mesas and scarps, and confined within valleys or craters. Plaut said, "The hypothesis is the whole area was covered with an ice sheet during a different climate period, and when the climate dried out, these deposits remained only where they had been covered by a layer of debris protecting the ice from the atmosphere."

 »We’ll just have to wait for the results of the laboratory tests.« These words are familiar to many patients. It then usually takes several days for specimens to be sent to the laboratory and analyzed and for the doctor to receive the results. For many illnesses, however, a speedy diagnosis is crucial if the treatment is to be successful. In future, the patient might only have to sit in the waiting room for a few minutes until the results are ready. In a joint project, researchers from seven Fraunhofer institutes have developed a modular platform for in vitro diagnosis which enables various types of bioanalysis – of blood and saliva for example – to be conducted in the doctor’s surgery. »Thanks to its modular design our IVD platform is so flexible that it can be used for all possible bioanalytical tasks,« states Dr. Eva Ehrentreich-Förster from the Fraunhofer Institute for Biomedical Engineering (IBMT) in Potsdam-Golm.The core element of the mini-laboratory is a disposable cartridge made of plastic which can be fitted with various types of sensor. For an analysis the doctor fills the cartridge with reagents – binding agents which indicate the presence of certain substances such as antigens in the specimen material. Various tests or assays are available for different types of analysis. To perform an assay, the doctor only has to place the relevant substances in the cartridge and the test then takes place automatically. »We have optimized the assays so that up to 500 assay reactions can be conducted in parallel in a single analysis step,« explains Dr. Ehrentreich-Förster. Even in the case of complex analyses the doctor obtains a result within about 30 minutes. A new module on the reverse side of the cartridge also makes it possible to analyze the specimen material at DNA level.Once the cartridge has been prepared, the doctor places it in the measurement system. The results can be read out with either optical or electrochemical biosensors. The researchers have installed a readout window for both methods in the measurement system, which features a bypass through which the specimen is pumped.

“Nanotubes assemblies of various types are black and highly conductive,” said Dr. Mikhail Kozlov, a research scientist and the study’s lead author. “Their dark, conductive surface can be effectively heated with laser light or electricity to induce variations in the pressure of the air around the nanotubes — which we perceive as sound. It’s called the photo- or thermo-acoustic effect, and it’s the same principle Alexander Graham Bell used to produce sound on the first telephone.” With laser excitation, no electrical contact with the nanotube speaker is required, making the speakers wireless. “Speakers made with carbon nanotube sheets are extremely thin, light and almost transparent,” Kozlov said. “They have no moving parts and can be attached to any surface, which makes the surface acoustically active. They can be concealed in television and computer screens, apartment walls, or in the windows of buildings and cars. The almost invisible strands form films that can ‘talk.’” In addition to filling a room with sound from invisible speakers, nanotube speakers could easily cancel sound from the noisiest neighbor or dim the roar of traffic rushing past a neighborhood, using the same principles as current sound-canceling technologies. “The sound generation by nanotube sheets can help to achieve this effect on very large scales,” Kozlov said.