Monday, March 1, 2010
3/01/2010 02:30:00 AM Publicado por Alquimia
What if it were possible to go to the store and buy a kit to quickly and accurately diagnose cancer, similar to a pregnancy test? A University of Missouri researcher is developing a tiny sensor, known as an acoustic resonant sensor, that is smaller than a human hair and could test bodily fluids for a variety of diseases, including breast and prostate cancers.
“Many disease-related substances in liquids are not easily tracked,” said Jae Kwon, assistant professor of electrical and computer engineering at MU. “In a liquid environment, most sensors experience a significant loss of signal quality, but by using highly sensitive, low-signal-loss acoustic resonant sensors in a liquid, these substances can be effectively and quickly detected — a brand-new concept that will result in a noninvasive approach for breast cancer detection.”
Kwon’s real-time, special acoustic resonant sensor uses micro/nanoelectromechanical systems (M/NEMS), which are tiny devices smaller than the diameter of a human hair, to directly detect diseases in body fluids. The sensor doesn’t require bulky data reading or analyzing equipment and can be integrated with equally small circuits, creating the potential for small stand-alone disease-screening systems. Kwon’s sensor also produces rapid, almost immediate results that could reduce patient anxiety often felt after waiting for other detection methods, such as biopsies, which can take several days or weeks before results are known.
“Our ultimate goal is to produce a device that will simply and quickly diagnose multiple specific diseases, and eventually be used to create ‘point of care’ systems, which are services provided to patients at their bedsides,” Kwon said. “The sensor has strong commercial potential to be manifested as simple home kits for easy, rapid and accurate diagnosis of various diseases, such as breast cancer and prostate cancer.”
(Photo: University of Missouri)
University of Missouri
3/01/2010 02:29:00 AM Publicado por Alquimia
Two University of Colorado at Boulder physicists are part of a collaborative team working with the U.S. Department of Energy's Brookhaven National Laboratory in New York that have created the hottest temperature matter ever measured in the universe -- 7.2 trillion degrees Fahrenheit.
The team used Brookhaven's giant atom smasher, the Relativistic Heavy Ion Collider, or RHIC, to ram charged gold particles into each other billions of times, creating a "quark-gluon plasma" with a temperature hotter than anything known in the universe, even supernova explosions. The experiment is recreating the conditions of the universe a few microseconds after the Big Bang.
CU-Boulder physics department Professors Jamie Nagle and Edward Kinney are collaborators on the Pioneering High Energy Nuclear Interaction eXperiment, or PHENIX, one of four large detectors that helps physicists analyze the particle collisions using RHIC. PHENIX, which weighs 4,000 tons and has a dozen detector subsystems, sports three large steel magnets that produce high magnetic fields to bend charged particles along curved paths.
RHIC is the only machine in the world capable of colliding so called "heavy ions" -- atoms that have had their outer cloud of electrons stripped away. The research team used gold, one of the heaviest elements, for the experiment. The gold atoms were sent flying in opposite directions in RHIC, a 2.4-mile underground loop located in Upton, New York. The collisions melted protons and neutrons and liberated subatomic particles known as quarks and gluons.
"It is very exciting that scientists at the University of Colorado are world leaders in laboratory studies of both the coldest atomic matter and now the hottest nuclear matter in the universe," said Nagle, deputy spokesperson for the 500-person PHENIX team.
In 1995 CU-Boulder Distinguished Professor Carl Wieman and Adjoint Professor Eric Cornell of the physics department led a team of physicists that created the world's first Bose-Einstein condensate -- a new form of matter. Both Wieman and Cornell are fellows of JILA, a joint institute of CU-Boulder and the National Institute of Standards and Technology where Cornell also is a fellow. The physicists, who shared the Nobel Prize in physics for their work in 2001, achieved the lowest temperature ever recorded at the time by cooling rubidium atoms to less that 170 billionths of a degree above absolute zero, causing individual atoms to form a "superatom" that behaved as a single entity.
The new experiments with RHIC produced a temperature 250,000 times hotter than the sun's interior. The collisions created miniscule bubbles heated to temperatures 40 times hotter than the interior of supernova. By studying the "soup" of subatomic particles created by the RHIC, researchers hope to gain insight into what occurred in the first microseconds after the Big Bang some 13.7 billion years ago, said Kinney.
Later this year physicists that include a team from CU-Boulder hope to use the Large Hadron Collider in Switzerland to ram ions together to create even hotter temperatures to replicate even earlier conditions following the Big Bang.
(Photo: U.S. Department of Energy)
University of Colorado at Boulder
3/01/2010 02:28:00 AM Publicado por Alquimia
While many of us enjoyed constructing little houses out of toy bricks when we were kids, this task is much more difficult if bricks are elementary particles. It is even harder if these are particles of light – photons, which can only exist while flying at an incredible speed and vanish if they touch anything.
A team at the University of Calgary has accomplished exactly that: by manipulating a mysterious quantum property of light known as entanglement, they are able to mount up to two photons on top of one another to construct a variety of quantum states of light – that is, build two-story quantum toy houses of any style and architecture.
The results of their research, written in the paper Quantum-optical state engineering up to the two-photon level, will be published on Nature Photonics's website on Feb. 14 at 1800 London time / 1300 Eastern time, which is also when the embargo will lift.
"This ability to prepare or control complex quantum objects is considered the holy grail of quantum science" says Andrew MacRae, a co-author of the paper and PhD physics student at the U of C. "It brings us closer to the onset of the new era of quantum information technology."
This new generation of technology is expected to endow us with qualitatively new capabilities. This includes measurement instruments of extraordinary sensitivity, dramatically faster computers, secure communication systems and enhanced control over chemical reactions.
"Light is a particularly interesting quantum object," says paper author Alexander Lvovsky, a professor in the Department of Physics and Astronomy, "because it's an excellent communication tool. No matter what future quantum computers will be made of, they'll talk to each other using photons."
U of C researchers used mirrors and lenses to focus a blue laser beam into a specialized crystal. This crystal takes high energy blue photons and converts them into a quantum superposition of lower energy red photons, which emerge in two directions, or 'channels'. By measuring one of the channels using ultra-sensitive single photon detectors, the physicists prepare the desired quantum state in the other.
Such an operation is possible because the photons in the two channels are entangled: a measurement made in one channel would result in an immediate change in the other, regardless of whether the particles were an arm's length apart or light years away. Albert Einstein called this quantum weirdness "spooky action at a distance."
"Quantum light is like an ocean," says Lvovsky, "and it's full of mysteries and treasures. Our task is to conquer it. But so far, physicists were able to control only a tiny island in this ocean. What we have done is to make this island bigger."
(Photo: Ken Bendiktsen)
University of Calgary