Chris Stephens, 28, who has been battling depression all of his life, plays with his dogs at home in Concord, Calif., on Friday. After a dose of ketamine, Stephens says, "I actually wanted to do things. I wanted to live life."
Lianne Milton for NPR
Nonnative pythons, like this one, are invading the Florida Everglades. As a top predator, the snakes have crippled the populations of rabbits, raccoons and other animals.
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Ketamine has been used as an anesthetic for decades. It's also a widely popular but illegal club drug known as "Special K." When administered in low doses, patients report a rapid reduction in depression symptoms.
The Delboeuf illusion makes one dot appear larger than the other. But they're the same size. Your brain is misled by comparing the dots to the surrounding circles.
Without a centralized national repository for nuclear waste, the radioactive material is currently being kept at various sites across the country. Above, large concrete canisters, each holding 14 55-gallon drums of waste, are loaded on a truck in 2005 in Richland, Wash., where they were later shipped to a facility in New Mexico.
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