Daniela Chavarriaga holds her daughter Emma as Dr. Jose Rosa-Olivares administers a measles vaccination at Miami Children's Hospital. Joe Raedle/Getty Images hide caption

itoggle caption Joe Raedle/Getty Images

Dr. Allan Ropper speaks with residents and fellows as they do rounds at the neuroscience intensive care unit at Brigham and Women's Hospital in Boston. M. Scott Brauer for NPR hide caption

itoggle caption M. Scott Brauer for NPR

Emily Whittington, a radiation therapist at Vanderbilt-Ingram Cancer Center, pulls down a mask intended to guide radiation beams into patients with head and neck cancer. Emily Siner/NPR hide caption

itoggle caption Emily Siner/NPR

Molecular biologist Randy Sheckman, who shared the 2013 Nobel Prize in physiology or medicine, acknowledges applause after receiving his prize during the ceremony in Stockholm last December. Pascal Le Segretain/Getty Images hide caption

itoggle caption Pascal Le Segretain/Getty Images

Biohazard suits used to handle dangerous microbes hang in a laboratory at the U.S. Army Medical Research Institute of Infectious Diseases in Fort Detrick, Md. Patrick Semansky/AP hide caption

itoggle caption Patrick Semansky/AP

Proton beam therapy can precisely target tumors to avoid harming surrounding tissue, advocates say. Blythe Bernhard/St. Louis Post-Dispatch/MCT/Landov hide caption

itoggle caption Blythe Bernhard/St. Louis Post-Dispatch/MCT/Landov

Justin McCowan poses for a portrait outside of his house in Santa Monica, Calif., on Aug. 14. Benjamin B. Morris for NPR hide caption

itoggle caption Benjamin B. Morris for NPR

"A person can never be broken. Our built environment, our technologies, are broken and disabled" — Hugh Herr Ryan Lash/TED hide caption

itoggle caption Ryan Lash/TED

"It's one of those moments in your life where you're so conscious about what you're about to do, and what you're about to do will change your life." --€” Geena Rocero James Duncan Davidson/TED hide caption

itoggle caption James Duncan Davidson/TED