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Scientists Build the World’s First Anti-laser

By Guest PostFebruary 20, 2011Scienceanti-laser, coherent light-light waves, gain medium, gallium arsenide, loss medium, near-infrared radiation, optical computing, scientific papers, yale university

More than 50 years after the invention of the laser, scientists at Yale University have built the world’s first anti-laser, in which incoming beams of light interfere with one another in such a way as to perfectly cancel each other out. The discovery could pave the way for a number of novel technologies with applications in everything from optical computing to radiology.

Conventional lasers, which were first invented in 1960, use a so-called “gain medium,” usually a semiconductor like gallium arsenide, to produce a focused beam of coherent light-light waves with the same frequency and amplitude that are in step with one another. (more…)

Replacing Body Parts Now More Than ‘Science Fiction’

By Guest PostFebruary 19, 2011Sciencecells, clinical trials, clotting, engineered lungs, genetically different cells, human body, human veins, infection, laura niklason, lunatic fringe, natural lungs, obstruction, regenerative medicine, science fiction, time of my life, tissue engineered lungs, tissue engineered replacement, vascular surgeons, vascular system

If Dr. Laura Niklason has her way, vascular surgeons will someday be able to pull human veins off a shelf, whenever they want, to save lives.

Niklason is a pioneer in the science — and art — of tissue-engineered replacement of human body components. Last year, she led a research team that successfully implanted tissue-engineered lungs, cultured in vitro, in adult rats. For short intervals of time, the engineered lungs exchanged oxygen and carbon dioxide similarly to natural lungs. (more…)

NASA Releases Images of Man-Made Crater on Comet

By Guest PostFebruary 17, 2011Science2005 deep impact mission, b 17 bomber, coma, comet, comet atmosphere, comet tempel 1, crater, denver, don brownlee, images, joe veverka, jpl, lockheed martin space systems, mission operations, NASA, new terrain, nucleus, pete schultz, stardust, stardust next, stardust spacecraft, tim larson, valentine day

PASADENA, Calif. — NASA’s Stardust spacecraft returned new images of a comet showing a scar resulting from the 2005 Deep Impact mission. The images also showed the comet has a fragile and weak nucleus.

The spacecraft made its closest approach to comet Tempel 1 on Monday, Feb. 14, at 8:40 p.m. PST (11:40 p.m. EST) at a distance of approximately 178 kilometers (111 miles). Stardust took 72 high-resolution images of the comet. It also accumulated 468 kilobytes of data about the dust in its coma, the cloud that is a comet’s atmosphere. The craft is on its second mission of exploration called Stardust-NExT, having completed its prime mission collecting cometary particles and returning them to Earth in 2006. (more…)

Astronomers Identify Thick Disc of Older Stars in Nearby Andromeda Galaxy

By Guest PostFebruary 16, 2011Scienceandromeda, andromeda galaxy, astronomer, evolution, formation of the andromeda system, galactic evolution, hawaii, hubble imaging, keck observatory, keck telescope, m31, michael rich, michelle collins, Milky Way, motions, robert gendler, scott chapman, spiral galaxy, spiral structure, thick stellar disc

An international team of astronomers has identified for the first time a thick stellar disc in the Andromeda galaxy, the nearest large spiral galaxy to our own Milky Way.

The discovery of the thick disc, a major result from a five-year investigation, will help astronomers better understand the processes involved in the formation and evolution of large spiral galaxies like ours, according to the team, which includes UCLA research astronomer Michael Rich and colleagues from Europe and Australia. (more…)

Quest for Designer Bacteria Uncovers a Spy

By Guest PostFebruary 15, 2011Sciencebacteria helper, biosensors, coerce bacteria, directed evolution, escherichia coli, james bardwell, mcgill university, molecular assistant, shu quan, spy

ANN ARBOR, Mich.—Scientists have discovered a molecular assistant called Spy that helps bacteria excel at producing proteins for medical and industrial purposes.

Bacteria are widely used to manufacture proteins used in medicine and industry, but the bugs often bungle the job. Many proteins fall apart and get cut up inside the bacteria before they can be harvested. Others collapse into useless tangles instead of folding properly, as they must in order to function normally. (more…)

Why Are Vines Overtaking the American Tropics?

By Guest PostFebruary 15, 2011Environment, ScienceAmazon, american tropics, barro colorado island, beauty kingdom, bolivian smazon, brazil, carbon, carbon storage, el nino events, english ivy, forest canopy, forests, french guiana, human communities, impact on animals, japanese honeysuckle, kudzu, liana vines, milwaukee, oliver phillips, oriental bittersweet, panama, planet, Smithsonian, south carolina, stefan schnitzer, subtropical forests, tropical forests, united states, vines

A Million-Dollar Question

Sleeping Beauty’s kingdom was overgrown by vines when she fell into a deep sleep. Researchers at the Smithsonian in Panama and the University of Wisconsin at Milwaukee received more than a million dollars from the U.S. National Science Foundation to discover why real vines are overtaking the American tropics. Data from eight sites show that vines are overgrowing trees in all cases.

“We are witnessing a fundamental structural change in the physical make-up of forests that will have a profound impact on the animals, human communities and businesses that depend on them for their livelihoods,” said Stefan Schnitzer, research associate at the Smithsonian Tropical Research Institute in Panama and associate professor at the University of Wisconsin at Milwaukee. (more…)

Delving Into Manganite Conductivity

By Guest PostFebruary 14, 2011Sciencealexander goncharov, atmospheres, breakthrough, chemical compounds, conductivity, electric charges, jahn teller effect, lamno3, magnetic random access memories, magnetic sensors, magnetoresistance, manganites, maria baldini, metallic state, mysterious ways, non conductive insulating state, spintronic devices, structure, viktor struzhkin

Washington, D.C.— Chemical compounds called manganites have been studied for many years since the discovery of colossal magnetoresistance, a property that promises important applications in the fields of magnetic sensors, magnetic random access memories and spintronic devices. However, understanding—and ultimately controlling—this effect remains a challenge, because much about manganite physics is still not known. A research team lead by Maria Baldini from Stanford University and Carnegie Geophysical Laboratory scientists Viktor Struzhkin and Alexander Goncharov has made an important breakthrough in our understanding of the mysterious ways manganites respond when subjected to intense pressure. (more…)

MU, ASU Researchers’ Discovery Could Change Views of Human Evolution

By Guest PostFebruary 13, 2011Scienceearly evolution, human evolution, human locomotion, human origin, human predecessor

3.2 million-year-old human predecessor had arches in feet

COLUMBIA, Mo. – Feet arches give humans a spring in their steps, shock absorbing abilities, and stiff platforms to propel themselves forward, allowing them to walk upright consistently. Now, researchers at the University of Missouri and Arizona State University have found proof that arches existed in a predecessor to the human species that lived more than 3 million years ago. This discovery could change scientists’ views of human evolution. The study is being published this week in Science. (more…)

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