How many calories in that bite? My Fitness Pal and other fitness and nutrition apps can help find the answer. Heather Rousseau/NPR hide caption
A construction worker paints walls at the Maryland Proton Treatment Center in Baltimore. Each of the center's five rooms will contain a massive piece of equipment that will rotate around a cancer patient to deliver a special kind of radiation. Jenny Gold/Kaiser Health News hide caption
Heart with congestive heart failure showing an enlarged left ventricle. Brian Evans/Science Source hide caption
Kaiba Gionfriddo, who breathes with help from a splint created by a 3-D printer, plays with his family dog, Bandit, at his Youngstown, Ohio, home. Mark Stahl/AP hide caption
An angiogram of a 48-year- old patient after treatment for a stroke. A blockage was targeted with clot-busting drugs using a catheter. Zephyr/Science Source hide caption
Lt. Cmdr. Stephen Mannino checks a sailor for skin cancer the old-fashioned way during a screening exam at Naval Amphibious Base Coronado in San Diego. MC2 Dominique M. Lasco/U.S. Navy hide caption
The barbs on porcupine quills make it easier from them to penetrate the skin. National Park Service hide caption
An electronic circuit in its first phases of dissolution. Fiorenzo Omenetto hide caption
A cross-sectional X-ray shows what's called a "sunken chest." The bright circle near the bottom is the spine; the gray blob on the right is the heart. Living LLC/Getty Images hide caption
Hugo Campos' implantable cardioverter-defibrillator was a mystery to him. So he decided to ask his doctor for access to the data. He made this image with one of his own X-rays. Hugo Campos hide caption