A tourist at the Bradbury Science Museum in Los Alamos, New Mexico, in February examines a full-size replica of the "Fat Man" atomic bomb which was dropped on Nagasaki, Japan, on Aug. 9, 1945. Los Alamos is home to the Los Alamos National Laboratory which was established in 1943 as part of the Manhattan Project. Robert Alexander/Getty Images hide caption

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"Self-regulation is about identifying the causes and reducing the intensity of impulses and, when necessary, having the energy to resist," psychologist Stuart Shanker writes in his book, Self-Reg: How to Help Your Child (and You) Break the Stress Cycle and Successfully Engage with Life. LA Johnson/NPR hide caption

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