1. Biological
Physics Group, School of Physics and Astronomy, The University of Manchester, Schuster
Building, Manchester M13 9PL, U.K.
2. Department
of Chemical and Biological Engineering, The University of Sheffield, Mappin Street, Sheffield S1 3JD, U.K.
3. SPD Development
Company Ltd., Priory Business Park, Bedford MK44 3UP, U.K.
4. Institut Laue
Langevin, 6 rue Jules Horowitz, 38042 Grenoble, France
5. EPSAM/ISTM, Keele University, Staffordshire ST5 5BG, U.K.