In a roundabout way, University of Virginia chemical engineering associate professor Joshua J. Choi and Commonwealth Professor of Physics Seung-Hun Lee are kindred spirits with artists who created the beautiful stained-glass windows found in medieval churches and cathedrals. They are using the same technology that produces colored glass to help the Department of Homeland Security keep America safe. More than25 million cargo containersarrive in the United States by sea, truck and train each year. Homeland Security, through Customs and Border Protection, is responsible for ensuring nothing inside the containers can be used to attack the country, including radiological, nuclear, chemical and biological devices or materials. It is the job of Homeland Security'sCountering Weapons of Mass Destruction Officeto stop threats at the border by giving customs agents and security personnel tools to find dangerous contraband. Choi and Lee recently began a $1.75 million project for the federal office to develop improved X-ray and gamma-ray radiation detection materials called scintillators. Over five years, Choi'soptoelectronics nanomaterials labat the UVA School of Engineering will receive $1.2 million of the overall grant, with the balance going to Lee's lab.