Amid a sweeping crackdown on dissent in Egypt, security forces have forcibly disappeared hundreds of people since the beginning of 2015, according to a new report from Amnesty International.

It's an "unprecedented spike," the group says, with an average of three or four people disappeared every day.

The Republican Party, as it prepares for its convention next week has checked off item No. 1 on its housekeeping list — drafting a party platform. The document reflects the conservative views of its authors, many of whom are party activists. So don't look for any concessions to changing views among the broader public on key social issues.

Many public figures who took to Twitter and Facebook following the murder of five police officers in Dallas have faced public blowback and, in some cases, found their employers less than forgiving about inflammatory and sometimes hateful online comments.

As Venezuela unravels — with shortages of food and medicine, as well as runaway inflation — President Nicolas Maduro is increasingly unpopular. But he's still holding onto power.

"The truth in Venezuela is there is real hunger. We are hungry," says a man who has invited me into his house in the northwestern city of Maracaibo, but doesn't want his name used for fear of reprisals by the government.

The wiry man paces angrily as he speaks. It wasn't always this way, he says, showing how loose his pants are now.

Ask a typical teenage girl about the latest slang and girl crushes and you might get answers like "spilling the tea" and Taylor Swift. But at the Girl Up Leadership Summit in Washington, D.C., the answers were "intersectional feminism" — the idea that there's no one-size-fits-all definition of feminism — and U.N. climate chief Christiana Figueres.

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Arizona Hispanics Poised To Swing State Blue

1 hour ago
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Editor's note: This report contains accounts of rape, violence and other disturbing events.

Sex trafficking wasn't a major concern in the early 1980s, when Beth Jacobs was a teenager. If you were a prostitute, the thinking went, it was your choice.

Jacobs thought that too, right up until she came to, on the lot of a dark truck stop one night. She says she had asked a friendly-seeming man for a ride home that afternoon.

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Vertical 'Pinkhouses:' The Future Of Urban Farming?

May 21, 2013
Originally published on May 23, 2013 5:58 pm

The idea of vertical farming is all the rage right now. Architects and engineers have come up with spectacular concepts for lofty buildings that could function as urban food centers of the future.

In Sweden, for example, they're planning a 177-foot skyscraper to farm leafy greens at the edge of each floor. But so far, most vertical gardens that are up and running actually look more like large greenhouses than city towers. And many horticulturists don't think sky-high farms in cities are practical.

"The idea of taking a skyscraper and turning it into a vertical farming complex is absolutely ridiculous from an energy perspective," says horticulturist Cary Mitchell of Purdue University, who's been working on ways to grow plants in space for more than 20 years.

The future of vertical farming, Mitchell thinks, lies not in city skyscrapers, but rather in large warehouses located in the suburbs, where real estate and electricity are cheaper.

And oh, yeah, instead of being traditional greenhouses lit by fluorescent lamps, he says these plant factories will probably be "pinkhouses," glowing magenta from the mix of blue and red LEDs.

Light is a major problem with vertical farming. When you stack plants on top of each other, the ones at the top shade the ones at the bottom. The only way to get around it is to add artificial light — which is expensive both financially and environmentally.

Vertical farmers can lower the energy bill, Mitchell says, by giving plants only the wavelengths of light they need the most: the blue and red.

"Twenty years ago, research showed that you could grow lettuce in just red light," Mitchell says. "If you add a little bit of blue, it grows better."

Plant's photosynthesis machinery is tuned to absorb red and blue light most efficiently. They have a handful of other pigments in their leaves that catch other wavelengths, but the red and blue wavelengths are the big ones, supplying the majority of the light needed to grow.

So why LEDs? They're super energy efficient in general, but unlike traditional greenhouse lamps, they can be tuned to specific wavelengths. Why use all of ROYGBIV when just RB will do?

And there's another advantage to using LEDs in greenhouses and vertical farming, Mitchell says: Because these lights are cooler, you can place them close to the plants — even stacked plants — and lose even less energy.

Recently, Mitchell and his graduate student designed a 9-foot-tall tower of lights and grew tomato plants right up against it. "As the plants get taller, we turn on the [light] panels higher up," he explains. "It takes about two months before all the panels are on."

The towers cut energy consumption by about 75 percent, Mitchell and his team reported earlier this year.

Right now, experiments are using these specialized LEDs to supplement natural light, not replace it.

But as LEDs get more and more efficient, could growers forgo the natural light altogether and grow crops completely in enclosed rooms, where they're protected from temperature changes or damaging pests?

That's exactly what Barry Holtz, at Caliber Biotherapeutics, is already doing.

His farms have never seen the light of day.

He and his company have built a 150,000-square-foot "plant factory" in Texas that is completely closed off from the outside world. They grow 2.2 million plants, stacked up 50 feet high, all underneath the magenta glow of blue and red LEDS.

"A photon is a terrible thing to waste," Holtz tells The Salt. "So we developed these lights to correctly match the photosynthesis needs of our plants. We get almost 20 percent faster growth rate and save a lot energy."

Holtz is growing a tobacco-like plant to make new drugs and vaccines. The indoor pinkhouse gives him tight control over the expensive crops, so his team can stop diseases and contamination.

Holtz says this type of indoor gardening isn't going to replace traditional farms anytime soon. It's still relatively expensive for growing food. "We couldn't compete with iceberg lettuce farmers," he says, "but for certain specialty crops, the economics wouldn't be so bad."

And, he says, the pinkhouse is actually quite efficient when it comes to water and electricity. "We've done some calculations, and we lose less water in one day than a KFC restaurant uses, because we recycle all of it."

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