Raul Castro, who has ruled Cuba since his brother Fidel stepped down in 2008, will leave the presidency on Thursday. And he has a successor in mind: Miguel Díaz-Canel, who is 30 years his junior.

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A brain imaging study of grown-ups hints at how children learn that "dog" and "fog" have different meanings, even though they sound so much alike.

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Everything you ever wanted to know about screen time, likes, and pull-to-refresh.

The votes will be held June 24, likely under a state of emergency and more than a year earlier than expected. The move hastens the implementation of reforms granting the presidency broad new powers.

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"We have a part of the aircraft missing, so we're going to need to slow down a bit," the pilot told air traffic controllers as she prepared to land with nearly 150 people onboard.

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The state's summertime ban on the use of a popular weedkiller has dissolved, for now, as a result of court decisions. Some confused farmers are rethinking their plans for this year's crops.

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As more schools band together to commit to recruiting and graduating 50,000 more low-income students, four college president discuss what it will take to get there.

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The U.S. territory was hit by an islandwide blackout, affecting more than 3 million people. Puerto Rico has struggled to rebuild its infrastructure since Hurricane Maria hit in September.

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Researchers use off-the-shelf robot parts to piece together one of those Stefan Ikea chairs.

Each night, the organisms gather in a "vertical stampede" to feed at the ocean's surface. Research suggests the columns of swimming animals can create large downward jets that help churn the waters.

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The idea is to inject anti-HIV antibodies that would kill the virus when people get exposed. A new study is promising — although it was conducted on monkeys.

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The former first lady, who died Tuesday, told Terry Gross in 1994 that she grew up thinking she'd be a nurse. "But then I met that marvelous George [H. W.] Bush and the nursing went out the window."

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Syrian state media said Tuesday that international inspectors had entered the site of a suspected chemical weapons attack. But the chemical weapons watchdog group OPCW now says that's not true.

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While the president has dismissed several national security advisers, Pompeo's role keeps growing. His secret trip to meet North Korean leader Kim Jong Un is just the latest and most dramatic example.

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For U.S. and other automakers, selling a car in China has always been difficult. But this week, China announced some moves that could pave the way for new sales for some manufacturers.

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Think twice before you tell your iPhone to trust that laptop when you charge it.

Also: Inspectors in Syria are still trying to visit the site of an alleged chemical weapons attack; more flooding is feared in Hawaii; and tumbleweeds pile up dramatically in southern California.

An FCC program promised to bring high-speed internet to remote schools. Instead, they've mostly gotten red tape.

Gerhard Schroeder went from chancellor of Germany to chairman of key Russian energy corporations. But many Germans are in no mood for more sanctions against Kremlin interests.

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These simple, battery-free devices provide an easy way to securely verify that it's really you who's trying to access your online accounts.