1. Key Laboratory of Magnetic Resonance in Biological Systems; State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics; Wuhan Center for Magnetic Resonance; Wuhan Institute of Physics and Mathematics; Chinese Academy of Sciences; Wuhan P.R. China
2. Department of Chemistry and Biochemistry; Califonia NanoSystem Institute; The Molecular Biology Institute; University of California; Los Angeles CA 90095 USA