None of this was easy. The pheromone is not only scarce but also delicate. It can wither under the heat generally used to isolate such compounds. So the scientists -- from North Carolina State University and two other schools -- employed a new method of low-temperature gas chromotography to separate out the molecule. Then they synthesized it and tested it on cockroaches. "They got really excited and ran right upwind toward the pheromone," says Coby Schal, a North Carolina entomology professor. The deaf can hear again -- at least, if they're lab animals. Working with guinea pigs, University of Michigan researchers first killed off hair cells in the ear that translate sound waves into electrical signals, which is the basis of hearing. In humans, the loss of such cells is a common cause of deafness. The researchers then used a modified virus to deliver a gene to other cells in the ear.
The gene normally is active only during the development of embryos, when it tells immature cells to transform themselves into hair cells. But the researchers were in for a surprise: The copy of the gene they added was not only active, it was capable of instructing even mature ear cells to turn into the crucial hair cells.
Eight weeks after the novel gene therapy treatment, the animals were able to hear sounds. The scientists now need to determine what the animals are hearing and see how long the effect lasts. The automatic transmission is an engineering wonder. A "planetary system" of gears provides a wide range of speeds to the wheels, while letting the engine operate in the narrow range of speeds where it's most efficient. But it doesn't scale up too well. The transmission of a big truck can weigh 1,200 lb. It wears out quickly and is a notorious energy hog.
Josef Wodeslawsky, an inventor and president of W.J. Sunns in Englewood, N.J., has designed a transmission that overcomes those problems. He says it will be one-third the size and half the weight of today's transmissions, as well as longer-lived and 20% more fuel-efficient. The trick: One of the gears can roll backward, the way a person might walk backward on a moving walkway, to slow the forward movement of the vehicle in relation to engine speed. This lets the vehicle idle and then get going easily from a standing start.
The design does away with two problematic parts. There's no need for clutch pads, which overheat and wear out. Nor does it require a torque converter -- an inefficient, oil-filled gizmo that eats energy. Wodeslawsky, who expects to have a working version completed by this summer, is talking with potential customers in government and business. What if a material could tell you it was about to fail? Your bumper might reveal that it's about to break from the stress of too many fender benders. Or the shrink-wrap around food could alert you to tiny ruptures, possibly protecting your family from illnesses.
Such failure-signaling plastics are being cooked up at Case Western Reserve University in Cleveland. A team led by engineering professor Chris Weder is mixing fluorescent dyes with standard polymers to create low-cost plastics that not only glow under black light, but also change color when stressed. As the researchers showed with a snippet of modified fishing line, the more a material is deformed, the bigger the color change.
Weder's recipe is also good at producing very consistent color effects. This could help foil counterfeiters if, for example, bills or packaging were doped with a mix that produces a certifiable color. CWRU has applied for patents, and glowing products could be available as early as 2008.