Could mirrors reduce the need for air conditioning around the world?

Stanford heat mirror

This mirror, when it is warmed up, releases heat at a specific wavelength of infrared light out into space.

Courtesy of Fan Lab, Stanford Engineering

Scientists working at Stanford University have developed a mirror that could replace air conditioners as the easiest and most efficient way to cool down buildings. The mirrors work by not just reflecting 97 percent of light away from buildings, but also by collecting heat energy and reflecting it literally into the cold depths of space.

Researchers say their mirror, if applied to the top of a three-story building, could save 100 MWh of electricity per building per year. The Guardian reports that while the mirror wouldn't be able to remove heat put off by humans — or cooking — inside a building, it could be used to cool water that could be circulated throughout the building to cool other sources of heat. In some circumstances, it might completely eliminate the need for air conditioning The mirrors cost between $20 and $70 per square meter to build and install, though there's no timeline for when this might be commercially available.

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This British girl is as big of a superhero fan as the boys and she wants everyone to know it

Karen Cole's daughter, Maggie, loves superheroes. She's certainly not the only girl who does, either. So you can imagine how upset Maggie was when she went to her local Tesco store in Poole, England, and came across a sign advertising a Marvel comics alarm clock as the "perfect gift for boys." Karen decided to snap a quick pic of her unhappy daughter and tweet it, telling Tesco it had screwed up by only thinking boys would like the alarm clock.

Well, 10,000 retweets later, and an untold number of news stories, Tesco is chagrined. They pulled down the sign and, at the same time, said the alarm clock would make a great gift for boys and girls. The BBC talked to Karen, who was amazed by the response her tweet generated and "very pleased" that Tesco had taken the sign down. There's an international campaign, Let Toys Be Toys, that urges publishers and toymakers not to target certain toys only at certain genders.

Why Nicholas Nixon's photography focuses on the dying

Nicholas Nixon has spent years of his career taking pictures of the dead and dying, starting largely with two projects from the 1980s — one about old people and one about people with AIDS. The project about people suffering from AIDS in the early days of the outbreak was particularly haunting. Fear and misunderstanding were rampant, and many viewed people with AIDS as almost alien. Nixon's photos served to break down that barrier.

"Once you know an individual, your stereotype always goes away," he says. Nixon's photographs have been collected on as part of a slideshow from PRI's To The Best of Our Knowledge's series on dying. Nixon says he was drawn to mortality before he even realized it. "Something drew me to life being short and sweet and sad early on.”

Putin's tiger is on a rampage

A few weeks ago, we told you about a rescued tiger that Russian President Vladimir Putin had released into the wild. The big cat wandered away from his Russian home and into China, where he's been making mischief. A lot of mischief. The tiger, named Ustin, is believed to have killed 15 goats and left another three missing — perhaps eaten or dragged away when Ustin raided a local farm.

Chinese wildlife officials are tracking the cat using a GPS collar he was fitted with while being raised in captivity in China. They've pledged to reimburse the local farmer for his lost goats, but they've instructed him to fortify his farm so Ustin — and other tigers like him — won't so easily be able to get in and get after the goats. The AP reports that two of the three tigers Putin released have now entered China, with the second already having attacked a chicken farm. 

Ever wondered where certain words come from?

Are you a ketchup fan, or a catsup fan? Have you given anyone a toast recently? And what about salad — how did that get its name? It turns out, many of our favorite foods and condiments got their names in especially interesting ways. Take salad, for example. It comes from the Latin phrase erba salata, which literally means salted greens. So, you could say, the word salad kind of means salted, which seems awfully counter-intuitive.

PRI's The World looked into a number of words and how they came to be what they are in English. Dan Jurafsky, a Stanford linguist and author of a book on the language of food, says the names for foods offer us clues to the "history of our culture and our globalization, and the way we’ve been interacting for a thousand years."

What we're seeing on social

There have been some conflicting reports about whether the passengers really pushed this plane, but it sure makes an interesting video:

Weather around the world

Months of relentless drought in Sao Paulo, Brazil, have dried up reservoirs and left people with little to no water coming out of the tap. Recent rains have, cruelly, mostly led to flooding, rather than refill empty reservoirs. But now people are taking the situation into their own hands. The Wall Street Journal reports on a surge in demand for installation of private water storage tanks that can take privately delivered water, or collected rain water, and feed it into a house's water supply. 

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