1. Molecular
Imaging Program, Stanford University, Stanford, California 94305, United States
2. Department
of Chemistry and Biochemistry, California State University Los Angeles, Los
Angeles, California 90032, United States
3. Department
of Animal Biology, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
4. Department
of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093, United States
5. Department
of Biological Sciences, University of Notre Dame, Notre Dame, Indiana 46556, United States