In Search of Time, X-Ray Tape, The Obese Brain, These Cones are Hot, Stressed Mama Birds


 

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In Search of Time


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Here's a simple question: what time it is now? Well, that's easy - just look at your watch. But here's a trickier one: what time is it on the other side of the universe? And when you say that time has passed, where did it go? And if time began with the Big Bang, what do we call the time before the Big Bang? It turns out that time is not such a simple concept after all. In fact, scientists and philosophers have been struggling for centuries to understand the true nature of time. Dan Falk, a Toronto-based science writer, has taken the time to explore those ideas in a new book, called In Search of Time: Journeys along a curious dimension.


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X-Ray Tape


xrt.jpg Courtesy Carlos Camara and Juan Escobar

The quest for an alternative energy source may finally be over. Dr. Carlos Camara is a post-doctoral physicist at the University of California, Los Angeles. He's found a remarkable source of energy from an entirely unlikely source -- a humble roll of office tape. If you've ever unwound a roll of sticky tape in the dark (and after all, who hasn't?), you may have noticed a faint strip of blue light where the tape comes off the roll. It's a phenomenon called triboluminesence and it's caused by the separation of positive and negative particles as the two surfaces of the tape are pulled away from each other. The charge separation creates enough energy to release light photons. Well, Dr. Camara wanted to know how far he could take this. So he placed the tape in a vacuum chamber and unwound it. The lack of gas in the vacuum allowed the tape to really show its energetic potential -- it produced much more light and, to Dr. Camara's surprise, a powerful bursts of x-rays. In fact, he was able to take an x-ray image of his own finger! Dr. Camara says that boosting this reaction by an order of magnitude could potentially release enough energy to create nuclear fission.


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The Obese Brain


two_chairs.jpg From Wikimedia Commons

The problem with food is that it tastes so darned delicious. After all, that seems to be why people overeat and become obese. But it may actually be more complicated than this. Cara Bohon, a doctoral student in clinical psychology at the University of Oregon, has been trying to figure out why some people are predisposed to gaining weight, while others aren't. Ms. Bohon has found that a brain region called the dorsal striatum is less active in obese people when they eat a delicious treat, than it is in slim people. This is a surprising result because this area is usually more active when we're enjoying a pleasurable treat, like a chocolate milkshake. She also found that obese people probably have this blunted pleasure response because their brains are less reactive to the neurotransmitter, dopamine. Ms. Bohon and her colleagues found that obese people tended to have a gene that leads to less dopamine activation in the brain. Together, these findings suggest that obese people actually enjoy their food less than slim people and, as a result, may end up eating more as they try to chase an elusive sense of satisfaction.


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These Cones are Hot!


hot_cones.jpg Optical and Infra-red pictures of seed cones - S Takács, Royal Society

Western conifer seed bugs have an appetite for the seeds within the cones of evergreen trees. What's more, they like hot food. Not so much because of the taste, but apparently because that's how they find the cones. Dr. Robb Bennett, an entomologist with the British Columbia Ministry of Forests, and his colleagues have found that conifer cones can be much hotter than the seeds and branches of the tree - up to 15 degrees C hotter. Furthermore, they discovered that the seed bug has developed a special set of infra-red "eyes" on its abdomen, which enable it to home in on the hot and tasty seed cones.


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Stressed Mama Birds


starling.jpg European Starling from Wikimedia Commons

Raising your young can be pretty stressful, particularly if you're a European Starling. It's not always easy to raise a brood -- there are predators to contend with, nasty weather and the never-ending quest for food. Scientists have recognized that this kind of long-term stress can cause a rise in the levels of a stress hormone called corticosterone. High levels of this hormone get passed on to baby birds through the egg, and can result in smaller chicks with weaker immune systems. But this may not be entirely bad. Dr. Oliver Love, a post-doctoral researcher in the Department of Biological Sciences at Simon Fraser University, has been studying the long-term effects of stress hormones on baby birds. Dr. Love found that while chicks that were raised by a high-stress mom may be smaller and weaker to begin with, they end up being well suited for a high-stress environment in the long run. If they do survive, they're able to get by on less food. They also end up being much more powerful fliers, making them better able to escape predators. Dr. Love says that the levels of a mother's stress hormone may serve as a signal to her unborn babes to come prepared for a tough life.


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Theme music bed copyright Raphaël Gluckstein. Creative Commons License by-nc-nd-2.0