Participants take part in a class at Judy's Group Fitness in Toronto, Ont. Aug. 31, 2009.Kevin Van Paassen/The Globe and Mail
A roundup of some of the week's science headlines:
Give me some (semantic) space: A group of scientists have mapped how the brain categorizes what we see, which they believe will lead to a more complete understanding of how the brain organizes objects and actions. The findings could help with treatment of brain disorders and spark new innovations in facial-recognition software, among other possible uses. The team sought to show which categories are represented in a similar fashion in the brain, and which aren't. Using MRI scanners, five study participants watched two hours of movie trailers with all objects and actions labelled. Then, the team built a model showing how parts of the brain's cortex – about 30,000 locations – responded to some 1,700 categories. The model was then analyzed to illustrate the brain's "semantic space" – related categories were physically close together, while disparate categories were distant from each other. Interestingly, all participants shared a similar semantic space, the team said in a release. As well, each category used more of the brain than previously thought, even overlapping with cortex locations associated with other categories, they said. The paper was published Wednesday in the journal Neuron, and the researchers also have put their interactive brain maps online. – Aleysha Haniff
Secret of youth? Scientists in Hong Kong appear to have mapped out a formula that can delay the aging process in mice, a discovery they hope to replicate in people.
In previous research into the premature aging condition known as progeria, the team at the University of Hong Kong found that a mutation in the Lamin A protein, which lines the nucleus in human cells, disrupted the repair process in cells causing accelerated aging. In their latest work, published in the December issue of Cell Metabolism, they found that normal and healthy Lamin A binds to and activates the gene SIRT1. Experts have long associated SIRT1 with longevity.
The team then tried to boost that effect using resveratrol, a compound found in the skin of red grapes and other fruits which has been touted by some scientists and companies as a way to slow aging or remain healthy as people get older. healthy mice fed with concentrated resveratrol fared significantly better than healthy mice not given the compound, living 30 per cent longer than progerial mice not given the compound. But don't grab a drink to celebrate yet: scientists say the negative effects of alcohol would outweigh benefits from the small amounts of resveratrol found in red wine. – Reuters
For fine arts and fisticuffs: A new study from the University of Utah suggests human hands evolved not just for tool-making but to throw a punch, offering a hint at the role aggression played in human evolution. Palms and fingers got shorter while the thumb became longer so humans could make a clenched fist, researchers said in a release. The scientists performed three experiments: in one, they showed a punch delivers more pressure than an open-palm slap, increasing the chance of injury to another person. The other two experiments showed how a fist protects the hand from injury when throwing a punch – the buttressing created when the study subjects formed a fist increased knuckle stiffness fourfold, and doubled the ability of the fingers to transmit the force behind a punch. The research was published Wednesday in the Journal of Experimental Biology. – Aleysha Haniff
Mission's end: A pair of NASA moon-mapping probes smashed themselves into a lunar mountain on Monday, ending a year-long mission that is shedding light on how the solar system formed.
The Gravity Recovery and Interior Laboratory, or GRAIL, spacecraft had been flying around the moon, enabling scientists to make detailed gravity maps. The probes sped up slightly as they encountered stronger gravity from denser regions and slowed down as they flew over less-dense areas. By precisely measuring the distance between the two probes, scientists discovered that the moon's crust is thinner than expected and that the impacts that battered its surface did even more damage underground.
Out of fuel and edging closer to the lunar surface, the probes were commanded to smash themselves into a mountain near the moon's north pole, avoiding a chance encounter with any Apollo or other relics left on the surface during previous expeditions. – Reuters