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Superconductors, Say Cheese


Why certain ceramic compounds become superconductors at relatively high temperatures still baffles the world's physicists. But new research from the University of Illinois is helping to unravel this enigma and could lead to better superconducting materials-perhaps even one that works at room temperature. Currently, so-called high-temperature superconductors must be cooled with liquid nitrogen to at least -225F.

Physicist Ali Yazdani's team has devised a way to visualize critical atomic structures in these ceramic materials-specifically, the copper-oxide layer. "This is the layer that's responsible for all the exotic properties," he says. The image above, published in Physical Review Letters last month, was hailed as providing the first-ever glimpse of this layer. The large red and blue shapes are orbital spheres of electrons around copper atoms. The small dumbbells are oxygen-atom orbitals, and the grape-like shape is the tip of a scanning tunneling microscope.

The Urbana-Champaign researchers also turned up what Yazdani terms "a big surprise": Electrons injected into this layer don't always behave as theory predicts. His team has proposed a model to explain that finding. Starting this fall, the IRS will make it easier for the visually impaired to hear, and complete, their tax forms.

The tax authority has enhanced 50 downloadable documents so they're compatible with standard speech-generation software. These programs-including JAWS, from Freedom Scientific in St. Petersburg, Fla., and Window-Eyes, made by GW Micro in Fort Wayne, Ind.-can automatically read aloud the text fields in onscreen tax forms. To build the software links between its cache of PDF-formatted documents and these speech-generation systems, the IRS worked with Plexus Scientific of Alexandria, Va., and Adobe Systems. "For people who strive so hard to be independent, having a tax form that talks to them is a victory," says Cyril St. Martin, a general manager at Plexus.

Plexus and Adobe are demonstrating the technology to other government bodies. Since all federal agencies are required to make their Web sites and documents more accessible to people with disabilities, the two companies should find plenty of willing listeners. Engineers seem to despise wires. First, they gave us wireless networks, such as WiFi, that let PCs share printers and modems. Then came Bluetooth, a short-range radio technology that can link PDAs with PCs or help connect headsets to phones.

Now a new standard promises to take wireless networks out of the office and into the family room. Dubbed WiMedia, it offers much greater range and higher speeds than Bluetooth but is cheaper and uses less power than WiFi. That combination should trigger a flurry of at-home link-ups for TVs, stereos, and other audio-video gear, says analyst Navin Sabharwal, a researcher at Allied Business Intelligence in Oyster Bay, N.Y.

Nearing approval by the Institute of Electrical & Electronics Engineers, the new 802.15.3standard transmits data over a range of 33 feet at a blistering 55 megabits per second-five times the speed of today's home nets and more than enough bandwidth to send digital video and audio signals flying from a DVD player in one room to a TV in another. Chips supporting the standard already have been announced by Vienna (Va.)-based XtremeSpectrum.

On Sept. 3, Hewlett-Packard (HPQ), Philips, Samsung, Sharp, and six other companies launched an alliance to promote WiMedia. By Christmas 2003, it may be built into camcorders, set-top boxes, and game consoles, at a likely price premium of $30. So much for that rat's nest of wires behind your home theater. -- In mid-September, a little robot is set to crawl up a mysterious shaft deep inside Egypt's Great Pyramid. At the end of the 9-inch-square, 245-foot-long tunnel is a stone slab with copper handles. What lies beyond, nobody knows. The robot will try to pierce this barrier with radar. If this indicates there's a secret room, the mini-explorer may also capture images by poking a tiny optical-fiber camera through a crack around the slab. The University of Chicago and the National Geographic Society are sponsoring the project.

-- After a heart attack, the difference between recovery and possible death is counted in minutes. To hasten treatment, researchers at Florida A&M University and Florida State University have developed a test to help medical staff detect heart attacks on the spot. It takes just three minutes, less than one-tenth as long as existing tests-not counting the time now needed to rush a blood sample to the lab. When mixed with blood, magnetic particles bind with so-called "cardiac markers," such as myoglobin. The markersarethen magnetically extracted and measured.

-- Synthetic diamond could be the ideal material for computer chips. Diamond chips could tolerate higher heat, better protect tiny circuitry from harmful radiation, and improve performance to boot. But most researchers gave up on diamond chips years ago. They just could not make diamond films as pure as the silicon substrates currently in use. Now, in the Sept. 6 Science, researchers at Sweden's ABB Group report that they have found a way to fabricate ultrapure diamond films.


Hollywood Goes YouTube
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