North Carolina State University News Services
Box 7504 Raleigh, NC 27695 (919) 515-3470
January 28, 1997
NC State News Tips A roundup of NC State University research, teaching and outreach activities For use by the media as briefs or as background for stories
Media Contact: Tim Lucas, News Services, 919/515-3470, [email protected]
From Fish, Come Clues on Sexual Behavior -- Scientists have long linked male sexual aggressiveness directly to hormones associated with sperm production in the testes. But two new studies of a gender-bending fish called the bluehead wrasse are challenging that axiom. The studies show, for the first time, that the development and expression of dominant-male sexual behavior can occur in animals without functioning testes, and that a hormone produced by another organ, the brain, may be the reason.
NC State zoologist Dr. John Godwin was one of five scientists from four universities who conducted the studies, which point to a hormone called arginine vasotocin, produced in the hypothalamus, as the driving force in gender-specific sexual behavior. Their findings were published in the Dec. 22, 1996, issue of the Proceedings of the Royal Society and in the November 1996 Proceedings of the Society for Neuroscience.
Paper From Cornstalks -- NC State scientists have found a new use for cornstalks, flax straw and other agricultural residues normally left in the field or flung on compost heaps. They're turning them into recyclable paper products. They're also making paper from industrial hemp, a non-psychoactive cousin of marijuana, and kenaf, a fast-growing African form of okra.
"It makes no sense, economically or environmentally, to let fiber from these sources go to waste when we have the technology to turn it into useful products like currency paper, newsprint, diaper fluff, boxes, even fine writing paper," says Medwick V. Byrd, director of applied research in wood and paper science at NC State. As a result of the research, the world's first bleached corn-fiber mill is scheduled to open in Nebraska in 1997. Mills for processing fiber from wheat straw, rice straw, flax straw, kenaf and industrial hemp also are planned or have been proposed.
Visionary Research -- A silicon microchip that acts as an artificial retina is being developed by scientists at NC State University, the University of North Carolina at Chapel Hill and Johns Hopkins University. The wafer-thin chip, which is just two millimeters square, could be surgically implanted in the eye to restore partial sight to people with retinal pigmentosa and other sight-robbing eye diseases. Photosensor cells and electrodes imbedded in the chip convert light and images into electrical impulses that stimulate nerves behind the retina -- thus restoring a person's ability to see forms and direction of movement. Lead designer Dr. Wentai Liu, an NC State electrical engineer, hopes to send chip prototypes to colleagues at Johns Hopkins this spring for biocompatibility testing. FDA approval is needed before testing can begin on humans
Better Housing for Migrant Workers -- A team of NC State architecture students led by professor Henry Sanoff are hoping to improve migrant worker housing. Working with farm owners, migrant workers and the North Carolina Department of Labor, the students have designed model migrant-housing facilities and compiled a list of practical, low-cost recommendations to improve facilities. The recommendations, based on site visits to migrant camps across North Carolina, were presented to the N.C. Commissioner of Labor in December 1996 and could be used in other states as well, Sanoff says. Suggestions include private sleeping quarters for married couples; bathrooms designed for use by one person at a time and separated physically from the kitchen; and increased private storage. "There needs to be a commitment among architects to (helping) people like these workers, who don't have advocates," says Sanoff.
Way-out Uses for a Buckyball Sibling -- Imagine an elevator stretching from Earth to an orbiting satellite 23,000 miles above. Way-out science fiction? That's what most people said when Arthur C. Clarke wrote about it in his 1978 novel Fountains of Paradise. But now, physicists at NC State say the idea may not be as far-out as it sounds.
Drs. Jerry Bernholc and Boris Yakobson have found that a man-made, honeycomb-shaped carbon material called nanotubes, a sibling of buckyballs, has great strength -- 10 to 12 times the strength of steel -- and is exceptionally lightweight. That makes it well-suited for use in a space elevator, where extreme strength and lightness would be needed to prevent the structure from collapsing under its own weight. Other, more down-to-earth uses for nanotubes include making better tennis racquets, bulletproof vests and car parts. Bernholc says if nanotube research continues at its current pace, products made of them could hit stores in about five years.
All's Fair in Love and Chores -- It may be the ë90s, but many couples are still old-fashioned when it comes to dividing household chores, says NC State sociologist Dr. Theodore Greenstein. In an analysis of The National Survey of Families and Households, Greenstein found that working wives still do more than 70 percent of the work around the house. Even more surprising, he says, is that it may be women themselves who are to blame for the lopsided distribution of labor in many houses. A woman with traditional views of marriage and family believes that housework is part of her job description. She doesn't expect her husband to do "women's work." And for their part, husbands usually live up to that expectation: Only one-fourth of men in the study did 40 percent or more of the household chores. Greenstein expects the numbers to even out a bit in coming years, as "husbands catch up with the shift to egalitarian views." His findings were published in August in the Journal of Marriage an
Cutting the Energy Costs of Computing -- Most computers are 90 percent energy efficient. That may sound pretty good, but to NC State electrical engineers Drs. Jayant Baliga and Manoj Mehrotra, it meant that 10 percent of all energy used by personal computers was being wasted -- quite a lot when you consider how many computers are used the world over.
To solve the problem, Baliga and Mehrotra have developed a patented device called the Trench MOS Barrier Schottky Rectifier (TMBS) which improves the energy efficiency of computers. The TMBS is designed to replace a device called the Schottky rectifier, where most of a computer's energy loss occurs. The TMBS generates about 60 percent less heat -- and therefore less wasted energy -- than the Schottky rectifier, Baliga says. He expects the new device to be available commercially within two years.
Getting to the Root of Hair Loss -- An estrogen-blocking compound used in cancer studies has been found to have an unexpected side effect: It induces hair growth in laboratory mice by stimulating inactive hair follicles. Treating the mice with a biologically active estrogen was found to have the opposite effect: It blocks hair growth by locking follicles into a resting mode. The discoveries, made by NC State toxicologist Dr. Robert C. Smart and doctoral candidate Hye-Sun Oh, suggest estrogen plays a more important role in hair growth than previously thought -- knowledge which could lead to new hair-loss treatments for humans.
"Our findings indicate that an estrogen receptor pathway in dermal papilla cells of the mice's hair follicles somehow acts as a switch...turning on and off hair growth," Smart says. He and Oh published their findings in October in Proceedings of the National Academy of Sciences.
A Thermostat With Universal Appeal -- Fights over thermostat settings are universal. Thermostats are not. That may change soon, however, thanks to researchers at NC State's Center for Universal Design, who are developing a universal thermostat to be used by disabled and nondisabled people alike. The need to develop the thermostat became apparent, says researcher Ron Mace, when the center's staff found that no such device was commercially available. The thermostat Mace and his colleagues have created to fill that void offers special features like a speaker for voice feedback; colored, raised arrows on temperature setting buttons; and remote control. Mace anticipates it will be in stores later this year.
Edible Film Fights Food-Borne Diseases -- NC State scientists have developed an edible film that reduces the spread of bacteria in poultry products and extends their shelf life.
The film, which is made from a protein called nisin, inhibits Salmonella, Listeria, E. Coli and other harmful bacteria capable of causing food-borne diseases. The refrigerated shelf life of poultry products dipped in or sprayed with the film can be extended by two to three days, tests show. Used in conjunction with bacteria-inhibiting meat tray pads, the film would provide extra safety for consumers, says researcher Dr. Brian W. Sheldon. And because it is gas-permeable and melts away when heated for cooking, it would not affect the food's taste or smell. Sheldon and colleagues at Clemson University have applied for a patent on the edible film technology.
A Promising New Plant ëVaccine' -- Despite its funny-sounding name, tomato spotted wilt is a virus that can infect more than 400 plant species, including important crops like tobacco and chrysanthemums. No method of control is available, but NC State plant pathologist Dr. Margaret Daub is developing a genetically engineered "vaccine" that may help turn the tables on the virus. Rather than inoculate plants in the field -- which would be costly and labor-intensive, and could cause the virus to mutate -- Daub genetically engineers certain varieties with the gene responsible for making viral coat protein. In field tests, only 10 percent of plants that produced the protein became infected when exposed to tomato spotted wilt. More tests are needed, but Daub is optimistic. "This seems to be a viable source of resistance," she says.
Textiles Take on New Dimensions -- Remember the name 3Tex Inc. The company, born and nurtured in an NC State laboratory, may spark great change in transportation- related industries with its new generation of lightweight, ultrastrong textile composite materials.
3Tex's latest patent is for a five-dimensional textile weaving technology that makes materials strong and light enough for use in building cars, planes or aerospace heat shields. Tests by a German automaker using a 3-D progenitor of the 5-D technology have shown that textile composites made with the 3-D technology outperform aluminum in strength and rigidity. The new 5-D technology produces even stronger materials, says 3Tex president Dr. Mansour Mohamed, an NC State textiles professor. "The technology has advanced significantly since we developed 3-D textile weaving a decade ago," he says. "We're just seeing the tip of the iceberg."
A Virtual Classroom -- A virtual classroom became reality at NC State this fall. Students at the University of North Carolina-Asheville, 250 miles away, signed up for an engineering course offered by NC State and took part in class discussions with their instructor in Raleigh -- all via computer. Dr. Tom Miller, assistant dean for information technology at NC State's College of Engineering, and graduate student Kathy Hewitt devised the technology that made the class possible. "We took Internet conferencing technology using the Virtual Multicast Backbone (MBONE) and applied it to teaching," Miller says. Unlike other long-distance learning technologies, the MBONE requires a much lower bandwidth, minimal special equipment and allows teachers and pupils to have real-time audiovisual interaction. NC State offers more than 100 long-distance courses each year via various networks and technologies.
-- lucas --
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