A handout photo provided by Dong-A Ilbo of North Korean leader Kim Jong Un and President Trump inside the demilitarized zone separating South and North Korea on June 30.
Dong-A Ilbo via Getty Images
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After multiple frustrations, U.S. strategists are asking if the North Korean leader is capable of making the nuclear deal the Trump administration wants.
Gray was diagnosed with sickle cell disease when she was an infant. She was considering a bone marrow transplant when she heard about the CRISPR study and jumped at the chance to volunteer.
Meredith Rizzo/NPR
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Herders bury animal carcasses in 2010 in Mongolia's Dundgovi province. A decade ago, an extreme winter — known in Mongolia as a dzud — claimed the lives of 22% of the nation's livestock and sped up migration from rural areas to urban centers.
Jargal Byambasuren/Reuters
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In Florida's Lake Okeechobee, huge blooms of blue-green algae have become an annual occurrence. The Army Corps of Engineers is testing methods based on wastewater treatment to remove the green slime, which can produce toxins that threaten drinking water supplies, local economies and human health.
Wilfredo Lee/AP
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A handout photo provided by Dong-A Ilbo of North Korean leader Kim Jong Un and President Trump inside the demilitarized zone separating South and North Korea on June 30.
Dong-A Ilbo via Getty Images
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Director of National Intelligence Dan Coats testifies before the Senate Intelligence Committee in January. Coats often operated behind the scenes, but when he spoke publicly, his assessments were often at odds with President Trump
Jose Luis Magana/AP
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