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  • NOVA scienceNOW

NOVA scienceNOW | Dark Matter, Of Mice and Memory, Hany Farid, Wisdom of the Crowds | PBS

Duration: 51:49 (Full Program)
Program: NOVA scienceNOW #301
Broadcast Date: Jun. 25, 2008

“Dark Matter”--Host Neil deGrasse Tyson reports from a half-mile underground in an abandoned mine, where scientists are using special detectors to look for evidence of a ghostly substance that they believe makes up most of the matter of the universe — a hypothetical entity called dark matter.

“Alzheimer’s/Memory Mice”--Researchers have found that mice with induced memory loss are able to retrieve memories either by being put into an enriched environment or by being given a drug that promotes beneficial gene activity in their brains. Such new insights may lead to a better understanding of dementia and other memory-impairment disorders, such as Alzheimer’s, in humans.

“Hany Farid”--Is seeing believing? In this age of easy photo manipulation, sometimes only a digital detective can tell. Enter Hany Farid, professor of computer science at Dartmouth College. He developed a program that can unmask photo tampering by analyzing light sources and other subtle features in an image — a service that turns out to be in high demand, especially during political campaigns.

“Wisdom of the Crowd”--Famed British scientist Sir Francis Galton (1822 to 1911), a proud aristocrat, thought he was proving the ignorance of the masses in his observation about a country-fair competition in which entrants were asked to guess the exact weight of an ox. The correct answer was 1,198 pounds; understandably, none of the 800 contestants got it exactly. “See!” said Sir Francis. “Decisions should be left to higher classes” — or sentiments to that effect. However, Sir Francis failed to realize that graphing all the guesses and determining their median produces the right answer and shows the “wisdom of the crowd.”



Post Date: June 10, 2009