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Scientists Power a Toy Car Using Evaporation

Scientists have long known how to use precipitation as a source of renewable energy. Now, it seems as though a team of researchers at Columbia University has figured out how to harness evaporation, too. 

Xi Chen and his colleagues noticed that spores of the bacterium Bacillus subtilis expand when they’re exposed to humidity and contract when they’re dry, behaving much like a muscle. When lined up on a piece of tape, the expanding and contracting spores were able to straighten and curl the strips of tape as the humidity of their environment changed. Their research is detailed in a paper published in the journal Nature Communications.

This discovery suggests that evaporation may be eventually be used as a source of power. During the study, the team observed that two strips of spores could make the tape scrunch, instead of curl, and several of them acting together could contract with enough force to lift small weights of 0.2 lbs to 0.7 lbs. This may not seem like much, but is in fact 50 times the weight of the strips themselves. They wondered if harnessing the collective force of these contractions could propel a device.

They tested that idea by building an "engine." The researchers stretched these so-called HYDRA strips horizontally over a small container of water covered with shutters. As the water evaporated, the strips expanded, causing the shutters to open. Once the water had been released, the humidity dropped, the spores contracted, and the shutters closed, allowing the process to begin again. By collecting, storing, and releasing the evaporation in a controlled, cyclic fashion, the researchers created a continuous power source. 

Chen and his team built another generator, resembling a spore Ferris wheel, which they dubbed the "Moisture Mill." They placed half of the wheel in a moist environment, and the other half in a less-humid space. The tiny imbalance created by the expansion of the spores in the humid environment caused the wheel to continuously tip forward, creating a rotation. This wheel was then affixed to a tiny toy car—thus creating the first evaporation-powered vehicle.

The possibilities for this newfound source of energy have yet to be fully explored, but researchers speculate that evaporation could someday be put to work in batteries, smart sportswear, and robotic limbs.

[h/t Discover]

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Afternoon Map
The Most Popular Infomercial Product in Each State

You don't have to pay $19.95 plus shipping and handling to discover the most popular infomercial product in each state: AT&T retailer All Home Connections is giving that information away for free via a handy map.

The map was compiled by cross-referencing the top-grossing infomercial products of all time with Google Trends search interest from the past calendar year. So, which crazy products do people order most from their TVs?

Folks in Arizona know that it's too hot there to wear layers; that's why they invest in the Cami Secret—a clip-on, mock top that gives them the look of a camisole without all the added fabric. No-nonsense New Yorkers are protecting themselves from identity theft with the RFID-blocking Aluma wallet. Delaware's priorities are all sorted out, because tons of its residents are still riding the Snuggie wave. Meanwhile, Vermont has figured out that Pajama Jeans are the way to go—because who needs real pants?

Unsurprisingly, the most popular product in many states has to do with fitness and weight loss, because when you're watching TV late enough to start seeing infomercials, you're probably also thinking to yourself: "I need to get my life together. I should get in shape." Seven states—Colorado, Idaho, Kentucky, Montana, Nebraska, Utah, and Wisconsin—have invested in the P90X home fitness system, while West Virginia and Arkansas prefer the gentler workout provided by the Shake Weight. The ThighMaster is still a thing in Illinois and Washington, while Total Gym and Bowflex were favored by South Dakota and Wyoming, respectively. 

Kitchen items are clearly another category ripe for impulse-buying: Alabama and North Dakota are all over the George Forman Grill; Alaska and Rhode Island are mixing things up with the Magic Bullet; and Floridians must be using their Slice-o-matics to chop up limes for their poolside margaritas.

Cleaning products like OxiClean (D.C. and Hawaii), Sani Sticks (North Carolina), and the infamous ShamWow (which claims the loyalty of Mainers) are also popular, but it's Proactiv that turned out to be the big winner. The beloved skin care system claimed the top spot in eight states—California, Mississippi, Nevada, New Mexico, Oklahoma, Oregon, Tennessee, and Texas—making it the most popular item on the map.

Peep the full map above, or check out the full study from All Home Connections here.

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Design
A Florida Brewery Created Edible Six-Pack Rings to Protect Marine Animals

For tiny scraps of plastic, six-pack rings can pose a huge threat to marine life. Small enough and ubiquitous enough that they’re easy to discard and forget about, the little plastic webs all too often make their way to the ocean, where animals can ingest or become trapped in them. In order to combat that problem, Florida-based Saltwater Brewery has created what they say is the world’s first fully biodegradable, compostable, edible six-pack rings.

The edible rings are made of barley and wheat and are, if not necessarily tasty, at least safe for animals and humans to ingest. Saltwater Brewery started packaging their beers with the edible six-pack rings in 2016. They charge slightly more for their brews to offset the cost of the rings' production. They hope that customers will be willing to pay a bit more for the environmentally friendly beers and are encouraging other companies to adopt the edible six-pack rings in order to lower manufacturing prices and save more animals.

As Saltwater Brewery president Chris Gove says in the video above: “We want to influence the big guys and kind of inspire them to also get on board.”

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