Stories of modern science... from UPI

, Jan. 2 (UPI) -- BABIES UNDERSTAND BABY TALK

Adults may not understand baby talk, but babies do, according to University of Washington researcher Patricia Kuhl and her team, as reported in New Scientist and this week's edition of the journal Nature. The researchers had previously studied the articulated vowel sounds that adults use to talk to babies and toddlers and found that they carry a different sound than the adult equivalent. The phenomenon occurs across languages, prompting them to wonder if baby talk helps babies learn to speak. They simulated learning by developing a simple speech-recognition computer program that picks out key vowels in English and attempts to distinguish between them. When listening to baby talk vowel sounds, the computer could easily distinguish them, but it had more difficulty with adult speech. Bart De Boer, a member of Kuhl's team, doesn't claim that the computer learns the same way babies do, but he says that babies probably more readily understand baby talk because of its distinct vowel sounds.

NEW DNA DEVICE BRINGS 'NANO-BOTS' ONE STEP CLOSER

A team of New York University researchers has taken a major step in building a more robust, controllable machine from DNA, the genetic material of all living organisms, according to a report in this week's edition of the journal Nature. The new device could be a foundation for sophisticated molecular machines, perhaps one day yielding nano-robots that can build new molecules and computer circuits or fight infectious diseases. Such devices make use of base pairing, in which two complementary strands of DNA self-assemble into a double helix. "Our findings have taken the first definitive step in localizing movement within molecular scale DNA machines, introducing independence of movement within a wider structure," said New York University chemistry professor Nadrian C. Seeman. In other words, the new development allows researchers to induce movement within the individual molecular pairs without affecting the position of other pairs in the larger structure of the double helix.

GREAT WHITES MIGRATE

It has long been believed that Great White sharks spend most of their lives near shore pursuing seals and sea lions, but a report in this week's edition of the journal Nature indicates that the awe-inspiring predators range across vast stretches of the open ocean. In fact, one male tagged along the Central California coast migrated thousands of miles to the waters off Hawaii - and remained there for nearly four months. "Until this study, white sharks had only been tracked for a few days around seal colonies. With the advent of new electronic tagging technology, we can now track their movement, depth and temperature preferences over many weeks and months" said Barbara A. Block, who is a professor of biological sciences at Stanford's Hopkins Marine Station in Pacific Grove, CA. The electronic tags recorded data every two minutes on water depth, temperature and light. "Light-level data allow you to calculate when sunrise and sunset occurs," said PRBO biologist Peter Pyle. "From the light data, we can calculate the longitude and latitude of the fish on Earth."

HEAT-SENSING CAMERA CAN TELL WHEN YOU'RE LYING

A new heat-sensing camera can catch people when they're lying. Reported by Norman Eberhardt and James Levine of the Mayo Clinic and Loannis Pavlidis of Honeywell Laboratories in this week's edition of the journal Nature, the camera can identify a rush of blood to the area around the eyes, a phenomenon that has been linked to lying. The temperature in the area may rise by as much as several degrees, but the camera must be very sensitive to catch the change at a distance of several feet. In tests, the camera had about the same accuracy as the conventional polygraph test, which is more complicated and time-consuming to use. "If the technology proves this accurate in the airport, it could revolutionize airport screening," Levine told New Scientist. "The ultimate concept is that you would ask someone if they were carrying a weapon and get an immediate response from the camera." Still, more work needs to be done, he conceded, as it is still not clear how the camera would take into account factors such as heating levels and recent exertion. Others are not so sure it's such a good idea. The system probably wouldn't work perfectly, and could make security workers complacent, said Aldert Vrij of the department of psychology at Portsmouth University. "There is the risk that people start to rely on it too much."

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