An image believed to be that of a hole-punch cloud. Scientists say airplanes create these patterns when they fly through certain types of clouds. The water in the clouds can turn to rain or snow and fall to the ground. H. Raab/Vesta/Wikimedia Commons hide caption

itoggle caption H. Raab/Vesta/Wikimedia Commons

Dr. Ray Dorsey video chats with his patient, Victor Jarzombeck, from his office at Johns Hopkins Medical Center in Baltimore. Dorsey has been treating Jarzombeck, who lives nearly 350 miles away in New Hartford, N.Y., for three years. Maggie Starbard/NPR hide caption

itoggle caption Maggie Starbard/NPR

Dr. Mark Lachs says his older patients are like reliable cars. After a certain age, they are less likely to break down, and just keep rolling right along. Adrian Kinloch hide caption

itoggle caption Adrian Kinloch