The new British Prime Minister Theresa May announced six members of her cabinet today.

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.

Copyright 2016 NPR. To see more, visit http://www.npr.org/.

Copyright 2016 NPR. To see more, visit http://www.npr.org/.

Copyright 2016 NPR. To see more, visit http://www.npr.org/.

Copyright 2016 NPR. To see more, visit http://www.npr.org/.

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If You Want A Doughnut Hole, Don't Ask A Mathematician

Jul 25, 2013
Originally published on August 27, 2013 11:27 am

Transcript

ROBERT SIEGEL, HOST:

From NPR News, this is ALL THINGS CONSIDERED. I'm Robert Siegel.

A program such as ours is timed to the exact second, and occasionally, there are small holes when our mix of news and features doesn't quite fill up our two-hour slot.

So NPR's Joe Palca offered to come to our rescue with some short math and sciencey hole-filling stories, stories about what else - holes.

JOE PALCA, BYLINE: Today, we're going to talk about doughnut holes, those round things you buy in a bakery. To a baker, it's not a troubling question to ask whether you can turn a doughnut into a doughnut hole. Simple. Instead of shaping the dough into a tube and dropping it in the deep fat fryer, you shape the dough into a sphere and drop it in the deep fat fryer.

For a mathematician, the question is more complex. In the mathematical world, a doughnut is referred to as a torus. And mathematicians who study the algebra of shapes have been arguing for more than a century whether there was any way you could bend or twist or compress a doughnut-shaped torus so it would turn into a sphere. In 1904, the French mathematician Henri Poincare said the answer was no, but he couldn't show why with mathematical reasoning, and neither could anyone else until finally 100 years later, the less famous Russian mathematician Grigori Perelman did find a way to prove you can't turn a torus into a doughnut hole.

The moral of the story is if you want a doughnut hole, don't ask a mathematician, ask a baker. But if you want to know about the shape of the universe, the mathematicians who worry about doughnut shapes can probably help with answers.

With the help of our mathematically trained intern Anna Haensch, I'm Joe Palca, NPR News. Transcript provided by NPR, Copyright NPR.