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Power

Li-Ion Batteries Get Green Seal of Approval 69

thecarchik writes "It is not an easy task to compare the environmental effects of battery powered cars to those caused by conventionally fueled automobiles. The degree to which manufacture, usage and disposal of the batteries used to store the necessary electrical energy are detrimental to the environment is not exactly known. Now, for the first time, a team of Empa scientists have made a detailed life cycle assessment (LCA) or ecobalance of lithium-ion (Li-ion) batteries, in particular the chemically improved (i.e. more environmentally friendly) version of the ones most frequently used in electric vehicles. Researchers decided to find out for sure. They calculated the ecological footprints of electric cars fitted with Li-ion batteries, taking into account all possible relevant factors, from those associated with the production of individual parts all the way through to the scrapping of the vehicle and the disposal of the remains, including the operation of the vehicle during its lifetime."
Hardware Hacking

Grad Student Invents Cheap Laser Cutter 137

An anonymous reader writes "Peter Jansen, a PhD student and member of the RepRap community, has constructed a working prototype of an inexpensive table-top laser cutter built out of old CD/DVD drives as an offshoot of his efforts to design an under $200 open-source Selective Laser Sintering (SLS) 3D printer. Where traditional laser cutters use powerful, fixed-focus beams, this new technique dynamically adjusts the focal point of the laser using a reciprocating motion similar to a reciprocating saw, allowing a far less powerful and inexpensive laser diode to be used. The technique is currently limited to cutting black materials to a depth of only a few millimeters, but should still be useful and enabling for Makers and other crafters. The end-goal is to create a hybrid inexpensive 3D printer that can be easily reconfigured for 2D laser cutting, providing powerful making tools to the desktop."
Privacy

Submission + - DOJ abandons warrantless access to Yahoo e-mail (cnet.com)

schwit1 writes: The U.S. Justice Department has abruptly abandoned what had become a high-profile court fight to read Yahoo users' e-mail messages without obtaining a search warrant first.

In a two-page brief filed Friday, the Obama administration withdrew its request for warrantless access to the complete contents of the Yahoo Mail accounts under investigation. CNET was the first to report on the Denver case in an article on Tuesday.

NASA

Submission + - Mum's the Word for NASA's Secret Space Plane X-37B (foxnews.com)

schwit1 writes: You would think that an unpiloted space plane built to rocket spaceward from Florida atop an Atlas booster, circle the planet for an extended time, then land on autopilot on a California runway would be big news. But for the U.S. Air Force X-37B project — seemingly, mum's the word.

There is an air of vagueness regarding next year's Atlas Evolved Expendable launch of the unpiloted, reusable military space plane. The X-37B will be cocooned within the Atlas rocket's launch shroud — a ride that's far from cheap.

Biotech

Submission + - Evolution May Lead to Shorter, Heavier Women 2

Hugh Pickens writes: "Yale University researchers report that while survival to reproductive age is no longer such a hurdle for humans, other evolutionary pressures – including sexual selection and reproductive fitness – are still working away in full force and if the trends detected in their study are representative and continue for another 10 generations, the average woman in 2409 AD will be 2 cm shorter, 1 kg heavier, will bear her first child five months earlier, and enter the menopause 10 months later. "There is this idea that because medicine has been so good at reducing mortality rates, that means that natural selection is no longer operating in humans," said Stephen Stearns of Yale University. "That's just plain false." Stearns and his team studied the medical histories of 14,000 residents of the Massachusetts town of Framingham, using medical data from a study going back to 1948 spanning three generations and found that shorter, heavier women had more children than lighter, taller ones. Women with lower blood pressure and cholesterol were also more likely to have large families as were women who gave birth early or had a late menopause. More importantly these traits are then passed on to their daughters, who also, on average, had more children. The study has not determined why these factors are linked to reproductive success, but it is likely that they indicate genetic, rather than environmental, effects. "The evolution that's going on in the Framingham women is like average rates of evolution measured in other plants and animals," said Stearns. ""These results place humans in the medium-to-slow end of the range of rates observed for other living things.""

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