Young boys wave smoldering tin cans at cars in Kabul, Afghanistan. The smoke from the seeds inside the cans is believed to ward off evil. Zabihullah Tamanna for NPR hide caption

Psychologist Diane Adams devotes a portion of her private practice in Renton, Wash., to veterans. But she said the bureaucracy involved in the Veterans Choice program has proved frustrating and veterans have had a hard time getting approval to see her. Patricia Murphy/KUOW hide caption

Republican presidential candidate Donald Trump at a campaign rally at the Redding Municipal Airport last Friday in Redding, Calif. Rich Pedroncelli/AP hide caption

Medical worker Abaare Hussein extracts a Guinea worm from a child's leg in Savelugu Village in northern Ghana in 2007. Wes Pope/Chicago Tribune/MCT via Getty Images hide caption

Former President Jimmy Carter delivers a lecture on the eradication of the Guinea worm at London's House of Lords on Feb. 3. The lecture title: "Final Days of the Fiery Serpent: Guinea Worm Eradication." Eddie Mullholland/WPA Pool/Getty Images hide caption

David Gilkey is seen in 2013 at NPR's Afghanistan bureau as he started a month in the country. David wore silver bracelets on his wrist as a kind of good luck charm. He said every time he had a near-death experience, he let one go. He threw one into the Euphrates River after the second battle of Fallujah. Another went into the Helmand River after he covered the arrival of U.S. Marines in 2009. Graham Paul Smith/NPR hide caption

Bob Guillo attended a Trump University retreat session which cost $35,000. He learned little from the program and later asked for his money back. Courtesy of Bob Guillo hide caption

Beth Cobert says cybersecurity has been boosted since she took over as acting director of the Office of Personnel Management last summer. Manuel Balce Ceneta/AP hide caption

China's President Xi Jinping (right), chats with U.S. Secretary of State John Kerry (center), and U.S. Treasury Secretary Jacob Lew during the joint opening ceremony of the U.S.-China Strategic and Economic Dialogues in Beijing on Monday. Andy Wong/AP hide caption

On some sunny, spring days, California has more electricity than it can use, like from this solar farm in Fresno. Terry O'Rourke/NREL hide caption

Hillary Clinton speaks to voters during a rally in El Centro, Calif., Thursday. She is on the precipice of becoming the Democratic nominee for president. The Washington Post/Getty Images hide caption