With temperatures on the rise and the first day of summer only 3 weeks away, pool season is just about upon us. Back in MAKE Volume 23, rocket engineer Edward Hujsak shared an efficient, low-cost, safe, and easy way to warm your pool. His project is the Lily Pad pool warmers, and they’re essentially made of hula hoops covered with black polyethylene film. The how-to is freely available for you on Make: Projects, where community member Daniel Busby commented, sharing the video he made of his Lily Pad build. The only difference between Edward’s instructions and Daniel’s build is that Edward used a soldering iron to spot weld the plastic to the hoops, and Daniel chose to use a household iron. Here’s Daniel’s video: 
In his article, Edward also included an interesting sidebar titled “The Pool Owner’s Dilemma”: The thermal behavior of swimming pools is complex, due to a number of factors that act to cool the water, while the sun and artificial means work to keep the water warm. Cooling forces are at work day and night, and include evaporation, conduction into surrounding soil, air current effects, and nighttime longwave (infrared) radiation into space. Gas-fired heaters are the most common pool warmers, but up-front costs for equipment and installation run into the thousands of dollars. And then there's the operating cost and the price of natural gas. These heaters are prodigious polluters; for an average-sized pool, a 1°F rise in temperature results in spewing 50lbs to 60lbs of carbon dioxide into the atmosphere. Roof-mounted solar heaters are a second option. Water from the pool is pumped through solar-heated heat exchangers and returned to the pool. Like gas-fired heaters, solar heaters are costly and are generally unsightly. They're also a problem in frost-prone areas. Bubble plastic blankets are passive devices that cover the pool. They function mainly as water conservation devices by inhibiting evaporation, thus slowing evaporative cooling. They also block nighttime radiation loss. Manufacturers claim these blankets also behave as warmers, transmitting additional energy from the sun into the water. But water already has a very low albedo (ratio of incident energy to reflected energy). It's about .10 for deep water, a bit higher in white-bottomed pools, and it's doubtful that bubble covers improve on that. (The low albedo of water is the reason for the great concern about the receding of the polar ice caps. Open water warms much more rapidly than ice fields, which reflect more than 80% of the sun's energy.) Moreover, pool blankets destroy the aesthetic appeal of a backyard pool; they're hard to manage, difficult to clean, and unsafe where small children are around; and they're often dumped after a single season.
         
Craig Venter's Bugs Might Save the World – NYTimes.com: In the menagerie of Craig Venter's imagination, tiny bugs will save the world. They will be custom bugs, designer bugs — bugs that only Venter can create. He will mix them up in his private laboratory from bits and pieces of DNA, and then he will release them into the air and the water, into smokestacks and oil spills, hospitals and factories and your house. Each of the bugs will have a mission. Some will be designed to devour things, like pollution. Others will generate food and fuel. There will be bugs to fight global warming, bugs to clean up toxic waste, bugs to manufacture medicine and diagnose disease, and they will all be driven to complete these tasks by the very fibers of their synthetic DNA.
Impressive article, I think this might kick off some popularization and interest in “biohacking”.          
The WW2 US Medical Research Centre has an extensive catalog of images and descriptions of World War II medical kits, vehicles, clothing, veterinary equipment, bags, field manuals, and more. There are also historical photos from the war sprinkled throughout. As the spelling of “centre” in the title gives away, the site was actually started by two European WWII medical collectors and re-enactors, Alain S. Batens and Ben C. Major. The "WW2 US Medical Research Centre" started out as a private venture between two WW2 US medical collectors and re-enactors living in Europe. Using a variety of sources, primarily original WW2 documents, we were able to create an on-line database containing the list of all WW2 US Medical Department Item Numbers and their descriptions. We soon realised that this database was an invaluable research tool for anyone interested in the period. As a result, the database was further expanded, and the basic project grew to encompass a number of other resources for both collectors and re-enactors to use for their research.
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