By Sharon Keeler
Illustrations by Jim Paillot
In this issue:Electronic Eye
It's a Wrap
Machines that see could soon help police investigate crime scenes and doctors examine cells for signs of disease.
Sound like science fiction? It isn't. At UNH's Synthetic Vision and Pattern Analysis Lab, professors and students are already working on these and other futuristic technologies.
"Synthetic vision, or machine vision, creates a system that mimics how humans see and perceive data," says lab director Richard Messner, associate professor of electrical and computer engineering. In the human eye, light reflected off an object is focused onto the retina. Photoreceptor cells convert the image into electrochemical impulses that travel to the brain, where "seeing" occurs. Similarly, synthetic vision involves using machines and computers to acquire images, digitize and compress the data into electrical signals, transmit those signals to a processor and then reconstruct the image.
Synthetic vision and pattern analysis research has enabled the development of now-common office fixtures like the photocopier, fax machine and scanner, as well as medical tests like the CAT scan and MRI.
Messner fingers a gizmo half the size of a business card. "This is used to power a machine that allows doctors to see inside arteries during cardiac catheterization. It performs about 30 million computations per second to provide real-time processed images from inside the body, which makes it possible for the doctor to undertake this procedure."
Synthetic vision engineering requires the compression of huge amounts of information before it can be transmitted. Messner is researching new compression schemes that will have implications for a variety of technologies. As an example, he cites the ability to broadcast real-time video images over the Web with greater clarity.
"The Web uses what's called bandwidth to carry information," says Messner. "It's like a pipe. To increase the water flow, you can increase the diameter of the pipe or the speed—the pressure—at which the water flows. I'm working on both challenges."
Messner's students are using the same technologies. Tony Pawlak '98G laid the groundwork for a machine that takes video images of cells and processes the image data for doctors to review. His work involved categorizing cells that indicate Huntington's disease. Graduate student Brian LaValley '97 is continuing Pawlak's research. According to Messner, once the system is complete, different computer programs can be used to help doctors distinguish various genetic diseases.
Messner is also developing technologies for law enforcement with colleague Tom Miller, professor of electrical and computer engineering. The project is funded by a $2 million grant from the U.S. Department of Justice. They will work on developing such devices as fingerprint scanners and real-time surveillance cameras.
It's hard to imagine life today without machines that can "see," and still harder still to imagine what lies ahead. Retina scans instead of passwords, video phones in every household, 3-D photographs: all are coming sooner than we think.
Why do people engage in behavior that is bad for them, even when they know the long-term risks? Why, for example, do people smoke, when there is overwhelming evidence that cigarettes are bad for their health?
Suzanne Mitchell, an assistant professor of psychology at UNH, is exploring this aspect of human behavior. Her research focuses on how the cost of things influences how people act.
"Cost-benefit analysis is not just a monetary issue. It's a process that involves how we balance our daily actions," says Mitchell. "For example, do we go for the immediate benefit of staying out late with friends, even though we know the cost of feeling tired tomorrow?"
Mitchell is applying cost-benefit analysis to addictive behaviors like smoking and gambling, hoping that better understanding might lead to more effective interventions. Her most recent study examines whether cigarette smokers have different personality traits than people who have never smoked. Specifically, Mitchell wants to know whether smokers are more impulsive.
"Previous studies have shown that impulsive people are more likely to experiment with drugs and become regular users," says Mitchell. "From a personality perspective, impulsivity is equated with preferences for immediate gratification, risky activities and novel sensations, as well as an inability to persist at a task and shorter reaction times.
"From a behavioral perspective, impulsivity is defined as the preference for a small immediate reward over a larger reward that is delayed or requires greater effort to obtain," she adds. "Like the personality perspective, the behavioral definition suggests that drug consumption and impulsivity may be linked. Individuals who choose to smoke cigarettes, for example, are essentially choosing the immediate reinforcing effects of cigarettes over a healthier future life."
The purpose of Mitchell's study was to determine whether cigarette smokers are more impulsive than nonsmokers, using a variety of measures of impulsivity. She compared 20 people who smoked at least 15 cigarettes a day with 20 people who had never smoked. All participants completed personality questionnaires and behavioral choice tasks.
Mitchell found that the regular smokers were significantly more impulsive than the nonsmokers. Twenty-six out of 28 scales from the personality questionnaires showed a difference in score between the two groups, and smokers showed a relatively strong preference for smaller immediate rewards.
While the differences in impulsivity between smokers and nonsmokers are clear, Mitchell says it is not known whether the higher scores on impulsivity measures reflect some intrinsic difference between the two groups or the direct effects of nicotine on the smokers.
"Psychopharmacologists are interested in answers to two questions," she notes. "First, are impulsive people more likely to use drugs? And second, do drugs like nicotine increase a person's level of impulsivity? It would be interesting to know whether the differences in personality and behavior existed before the smokers started to smoke. If the answer is yes, personality questionnaire data may be useful to identify people who are likely to begin smoking and who might benefit from interventions aimed at discouraging smoking."
It's a Wrap
Since the dawn of human history, we have taken food and other resources from the sea without showing much concern for the preservation or management of those resources. That will change in the 21st century as aquaculture becomes a major industry.
Scientists at UNH are at the forefront of discovery in this developing field. Geneticist Anita Klein is a good example. She and her students are collaborating with a group of New England scientists to measure the diversity of a type of seaweed called Porphyra.
Porphyra grows in estuaries and the rocky intertidal region along the coast. It is a deep red to greenish-brown color, has a smooth, rubbery texture and is only two cell layers thick. A Japanese species is cultivated to make nori, the wrapper used for sushi. Japan is the principal consumer of nori and the major exporter to the United States, capitalizing on a $2 billion industry it shares with Korea and China. Cultivating this marine plant for local sale and export could be a lucrative business for New England growers.
"Our overall goal is to be able to adapt local species for seaweed aquaculture," Klein says. While seaweed is harvested for commercial applications—to produce agar for the medical industry, for example—it has not been grown successfully in the United States through aquaculture. A major Porphyra venture in Eastport, Maine, was unsuccessful because it used a non-native species that did not adapt well. Scientists believe that New England Porphyras have great potential for nori aquaculture, but they have little baseline information about the different species.
Klein is working with fellow UNH researchers Art Mathieson and Chris Neefus '82 to learn which species thrive in various types of environmental conditions. Salinity, temperature, availability of nutrients, currents and wave activity all play a part in determining where a Porphyra species decides to take up residence.
Klein and her students are trying to find better genetic markers to distinguish each of the six native New England species. Because Porphyra species look pretty much alike, characteristics like thickness, color or shape do not reliably differentiate one from another.
In Klein's laboratory, sophisticated scientific techniques are used to decode the genetic fingerprint of each Porphyra species. Finely chopped bits of plant tissue are suspended in a DNA preservative, rapidly frozen in liquid nitrogen and immediately thawed in warm water. This freeze/thaw cycle is repeated twice. Individual genes can then be divided into DNA fragments, which are separated in an electric field to produce distinct banding patterns for each species.
"This type of work is most important to commercialization of native Porphyra species," says Klein. "Once you can accurately identify a certain species, you can pair it with its bioecological characteristics. What does it need to thrive, in terms of water temperature, nutrients and salinity? This is the type of information people will need as they make decisions about whether it's economically feasible to grow Porphyra."
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