1. School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, U. K.
2. Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, U. K.
3. Graduate School of Agricultural Science, Kobe University, Rokkodaicho 1-1, Nada, Kobe 657-8501, Japan
4. Graduate School of Agricultural Science and Biosignal Research Center, Kobe University, Rokkodaicho 1-1, Nada, Kobe 657-8501, Japan