16. Image sources Courtesy of NASA Marshall Space Flight Center Courtesy of IBM iStockphoto.com Image copyright Dennis Kunkel Microscopy, Inc. Sciencenter, Ithaca, NY
17. Image sources (continued) Courtesy of Tejal Desai and University of California San Francisco Courtesy of Stanley Williams and Hewlett-Packard Courtesy of Antje Baeumner and Cornell University
18. This project was supported by the National Science Foundation under Grant No. ESI-0532536. Any opinions, findings, and conclusions or recommendations are those of the author and do not necessarily reflect the views of the Foundation.