Dee Faught tests a robotic arm installed on his wheelchair in September. Commercially produced robotic arms can cost tens of thousands of dollars, but three Rice engineering students built one for Dee for about $800. Eric Kayne for NPR hide caption

itoggle caption Eric Kayne for NPR

Dr. Jim Olson meets with Carver Faull at Seattle Children's Hospital in August. Carver, now 12, had surgery to remove a brain tumor in 2012. Matthew Ryan Williams for NPR hide caption

itoggle caption Matthew Ryan Williams for NPR

The image on the left is a piece of lung tissue that contains a tumor viewed under normal white light. The right image shows the same piece of tissue after Tumor Paint has been applied. Here it's viewed under infrared light. Areas that are more red and yellow show a concentration of the paint, which means they are more likely to be cancerous. Courtesy of Julie Novak/Blaze Bioscience hide caption

itoggle caption Courtesy of Julie Novak/Blaze Bioscience

NASA's Solar Dynamics Observatory captured this picture of the sun on June 18. The dark blue area in the upper left quadrant of the sun is a huge coronal hole more than 400,000 miles across. Coronal holes are areas of the sun's outermost atmospheric layer — the corona — where the magnetic field opens up and solar material quickly flows out. NASA/SDO hide caption

itoggle caption NASA/SDO

Wood fibers are coated with carbon nanotubes and then packed into small disks of metal. The sodium ions moving around in the wood fibers create an electric current. Heather Rousseau/NPR hide caption

itoggle caption Heather Rousseau/NPR

Before And After: These near-infrared images of Uranus show the planet as seen without adaptive optics (left) and with the technology turned on (right). Courtesy of Heidi B. Hammel and Imke de Pater hide caption

itoggle caption Courtesy of Heidi B. Hammel and Imke de Pater

AnthroTronix Founder and CEO Corinna Lathan, at the company's offices in Silver Spring, Md. Courtesy of AnthroTronix, Inc. hide caption

itoggle caption Courtesy of AnthroTronix, Inc.

Jonathan Wilker holds up a group of oysters from a tank in his lab at Purdue University. Rebecca Davis/NPR hide caption

itoggle caption Rebecca Davis/NPR