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Bats Save Energy By Drawing in Wings on Upstroke

By Guest PostApril 13, 2012Nature, Scienceaerodynamics, attila bergou, bat wings, bats, brown university, calculation, calculus rich model, daniel riskin, david orenstein, flying machine, inertial energy, muscular wings, physicisist, sharon swartz, wing mass

Bat wings are like hands: meaty, bony and full of joints. A new Brown University study finds that bats take advantage of their flexibility by folding in their wings on the upstroke to save inertial energy. The research suggests that engineers looking at flapping flight should account for wing mass and consider a folding design.

PROVIDENCE, R.I. [Brown University] — Whether people are building a flying machine or nature is evolving one, there is pressure to optimize efficiency. A new analysis by biologists, physicists, and engineers at Brown University reveals the subtle but important degree to which that pressure has literally shaped the flapping wings of bats.

The team’s observations and calculations show that by flexing their wings inward to their bodies on the upstroke, bats use only 65 percent of the inertial energy they would expend if they kept their wings fully outstretched. Unlike insects, bats have heavy, muscular wings with hand-like bendable joints. The study suggests that they use their flexibility to compensate for that mass. (more…)

Newfangled Space-Propulsion Technology Could Help Clean up Earth Orbit

By Guest PostApril 12, 2012Scienceatmosphere, dead satellite, debris, earth, earth orbit, geosynchronous orbit, humans, international space station, mag beam, magnetized beam, magnetized ion plasma, mars, planet, plasma propulsion device, real estate, robert winglee, space junk, spacecraft, system, ultra high speed

Some of the most valuable “real estate” for humans isn’t on Earth at all but rather above the planet’s atmosphere, where all manner of human-made objects orbit. The problem is that those orbits are too crowded with dead satellites and debris, making new launches riskier.

Robert Winglee has spent years developing a magnetized ion plasma system to propel a spacecraft at ultra-high speeds, making it possible to travel to Mars and return to Earth in as little time as 90 days. The problem is that cost and other issues have dampened the desire to send astronauts to Mars or any other planet. (more…)

Exciting New Field of Bioorthogonal Chemistry Owes a Debt to Curiosity-Driven Research from Previous Eras

By Guest PostApril 11, 2012Sciencebioorthogonal chemistry, chemistry for life, click chemistry, staudinger ligation

Carolyn Bertozzi’s Kavli Lecture Highlights Promise of Biorothogonal Chemistry and Its Links to Basic Research From the Past

“Bioorthogonal chemistry is literally chemistry for life,” said Carolyn Bertozzi, an internationally acclaimed leader and founder of this emerging and highly promising field of science that could fundamentally change drug development and disease diagnostics. In delivering the Kavli Foundation Innovations in Chemistry Lecture at this year’s Spring Meeting of the American Chemical Society (ACS) in San Diego, Bertozzi described how her own ground-breaking research made use of experiments nearly a century ago by two German chemists whose work was driven primarily by scientific curiosity as opposed to the more problem-driven research of today. (more…)

Scientists Use PET to Predict Increased Survival in Cancer Patients After First Chemo Cycle

By Guest PostApril 10, 2012Sciencechemotherapy drugs, ct scan, cycle, fdg, fritz eilber, metabolic activity, molecular imaging tools, neoadjuvant chemotherapy, patient, pet scan, soft tissue sarcomas, survival rate, tumor

Researchers from UCLA’s Jonsson Comprehensive Cancer Center have found that by administering a PET scan to individuals with soft-tissue sarcomas after just a single cycle of neoadjuvant chemotherapy, they can predict increased survival in these patients.

Prior research by this multidisciplinary team of physician-scientists had shown that a combined PET/CT scan using a glucose uptake probe called FDG allowed them to determine the pathologic response of patients’ tumors after the first dose of chemotherapy drugs. They then wondered if the patients who showed a significant PET response after the first round of chemotherapy also were surviving longer. (more…)

Transactional Memory: An Idea Ahead of Its Time

By Guest PostApril 10, 2012Science, Technologyamherst, ars technica, blue gene, brown university, buzz, computer, computer scientist, computing technology, core processor, eliot moss, hardware architecture, hardware computing, haswell, ibm, maurice herlihy, mike cohea, parallel processor, q supercomputer, richard lewis, transactional memory, university of massachusetts

Nearly 20 years ago, two Brown University computer scientists were working on a largely theoretical problem: How could multiple parallel processors make changes to shared resources safely and efficiently? Their proposal — transactional memory — is sparking fresh interest as a new generation of processors seeks improved power and speed.

In 1993, Maurice Herlihy and a colleague published a paper on transactional memory — a new, clever tactic in computing to deal with handling shared revisions to information seamlessly and concurrently. Few noticed.

Nearly 20 years later, transactional memory is an idea that’s now the rage in hardware computing, and Herlihy, computer science professor at Brown University, has morphed into a prophet of sorts, a computing pioneer who was far ahead of his time. Intel recently announced that transactional memory will be included in its mainstream “Haswell” hardware architecture by next year. IBM has adopted transactional memory in the Blue Gene/Q supercomputer. The original paper by Herlihy and Eliot Moss has been cited more than 1,300 times. (more…)

The Weird World of “Remote Heating”

By Guest PostApril 10, 2012Sciencejoule heating, remote heating, remote joule heating

UMD Researchers Discover Nanoscale Phenomena with Potential for Computer Speed Advances

College Park, Md.– A team of University of Maryland scientists have discovered that when electric current is run through carbon nanotubes, objects nearby heat up while the nanotubes themselves stay cool, like a toaster that burns bread without getting hot. Understanding this completely unexpected new phenomenon could lead to new ways of building computer processors that can run at higher speeds without overheating. (more…)

Images Capture Split Personality of Dense Suspensions

By Guest PostApril 9, 2012Sciencedna microarray, drop forms, heinrich jaeger, jeffrey morris, marc miskin, mathematical model, nozzle diameter, particle, phenomena, steve koppes, university of chicago, viscosity, viscous, viscous liquids, viscous mixture, zirconium dioxide

Stir lots of small particles into water, and the resulting thick mixture appears highly viscous. When this dense suspension slips through a nozzle and forms a droplet, however, its behavior momentarily reveals a decidedly non-viscous side. University of Chicago physicists recorded this surprising behavior in laboratory experiments using high-speed photography, which can capture action taking place in one hundred-thousandths of a second or less.

UChicago graduate student Marc Miskin and Heinrich Jaeger, the William J. Friedman and Alicia Townsend Friedman Professor in Physics, expected that the dense suspensions in their experiments would behave strictly like viscous liquids, which tend to flow less freely than non-viscous liquids. Viscosity certainly does matter as the particle-laden liquid begins to exit the nozzle, but not at the moment where the drop’s thinning neck breaks in two. (more…)

12-Mile-High Martian Dust Devil Caught in Act

By Guest PostApril 6, 2012Scienceamazonis planitia, dust devil, earth, hirise camera, mars reconnaissance orbiter, martian dust devil, martian surface, meteorite impact, NASA, northern mars, northern summer solstice, plume, red planet, tucson, university of arizona

A Martian dust devil roughly 12 miles high (20 kilometers) was captured whirling its way along the Amazonis Planitia region of Northern Mars on March 14. It was imaged by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA’s Mars Reconnaissance Orbiter. Despite its height, the plume is little more than three-quarters of a football field wide (70 yards, or 70 meters).

Dust devils occur on Earth as well as on Mars. They are spinning columns of air, made visible by the dust they pull off the ground. Unlike a tornado, a dust devil typically forms on a clear day when the ground is heated by the sun, warming the air just above the ground. As heated air near the surface rises quickly through a small pocket of cooler air above it, the air may begin to rotate, if conditions are just right. (more…)

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