A. John Hart, an assistant professor in the Department of Mechanical Engineering, has created 3-D portraits of the president-elect that are smaller than a grain of salt. He calls them "nanobamas." Hart made the mini-Barack Obama likenesses with his colleagues to raise awareness of nanotechnology and science. Each one contains about 150 million carbon nanotubes stacked vertically like trees in a forest. A carbon nanotube is an extraordinarily strong hollow cylinder about 1/50,000th the width of a human hair.