1. Harvard-MIT Division of Health Sciences and Technology, Cambridge, Massachusetts, Cancer Research Center, Burnham Institute for Medical Research, La Jolla, California, Vascular Mapping Center, Burnham Institute for Medical Research at University of California Santa Barbara, Santa Barbara, California, Materials Science and Engineering Program, Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093, and Electrical Engineering and Computer Science,...