Make Pee, Not War, Wat was Up With Angkor, Venusian Vulcanism, Bright Ideas - 50 Years of Lasers

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Make Pee, Not War

crayfish.jpg Urine Trouble, courtesy Fiona Berry; BMC Biology

In the signal crayfish species, urine is the key to communicating aggressive intentions. But the female urine has a dual purpose. Dr. Fiona Berry, formerly at the University of Hull in England, and now with the conservation group Natural England in York, has found the meaning of the female's mixed messages. The female releases a puff of urine in the presence of the male. The male is able to recognize a chemical in the urine that tells him two things. One is an aphrodisiac signal that says she's ready to mate; the other is an aggressive message to the male that says, "if you want to mate, show me how tough you are." This way, the female is assured of mating with the toughest, fittest male.

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Wat was Up With Angkor?

angkor_wat.jpg Angkor Wat, copyright Manfred Werner, cc-by-sa-3.0

The ancient city of Angkor was the seat of the Khmer empire that dominated Southeast Asia for centuries. Its mysterious decline in the 14th and 15th centuries has puzzled historians. But new work reconstructing the climate of the region may suggest part of the solution to that mystery. Dr. Brendan Buckley, a research scientist at the Lamont Doherty Earth Observatory of Columbia University in New York, and his group, used growth records preserved in tree-rings to show that Angkor would have suffered decades-long droughts, interspersed with unusually intense monsoons. This boom-bust cycle would have been extremely destabilizing for Angkor, which depended on a complex system of canals and reservoirs for water.

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Venusian Vulcanism

venus_volcano.jpg Infrared picture of the volcanic peak Indunn Mons, courtesy NASA/JPL-Caltech/ESA

Venus had veritable vistas of volcanoes in its past. We learned from the Magellan spacecraft, which mapped the Venusian surface with radar, that giant volcanoes and lava flows had shaped Venus' surface. But there were no signs to indicate whether Venus was still volcanically active. Now, a team using an instrument on the European Space Agency's Venus Express spacecraft has found signs of volcanic flows that are only hundreds of thousands to a couple of million years old - practically brand-new in geological terms. Dr. Suzanne Smrekar, a research scientist at NASA's Jet Propulsion Laboratory in California, and her team, found rock with a characteristic heat signature that indicated that it was from a relatively fresh volcanic flow.

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Bright Idea: 50 Years of the Laser

laser.jpg The first Laser

The next time you play a DVD, go through the check-out at the grocery story or just make a phone call, you'll be using one of the most important inventions of the 20th century - but one that you can't always see. It's crucial to modern communications, industry, medicine and science. And fifty years after its invention, people are still finding new uses for it. The laser has come a long way in its first 50 years. At the time of its invention, many people called it a solution looking for a problem. And like many great inventions, the laser began as an idea, starting with Einstein, then became a competition among scientists to be the first to make one that actually worked. That race was won on May 16th, 1960 at the Hughes Laboratories in California by physicist Dr. Theodore Maiman, who late in life moved to Vancouver where he was an adjunct professor at Simon Fraser University. Jeff Hecht, a science and technology writer and author of Beam: The Race To Make The Laser, looks at the history of the laser and the men who strove to be first.

Dr. Paul Corkum, Canada Research Chair in Attosecond Photonics from the Department of Physics at the University of Ottawa, uses a very sophisticated form of laser in his research: he developed attosecond laser pulses - flashes of light so short that they can provide images of electrons moving around atoms. He explains how the laser works and some of its applications for the future.

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Theme music bed copyright Raphaël Gluckstein.
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