1. Department
of Neuroscience, Physiology and Pharmacology, University College London, Gower Street, London WC1E
6BT, United Kingdom
2. Centre
for Mathematics and Physics in the Life Sciences and Experimental
Biology, University College London, Gower Street, London WC1E 6BT, United Kingdom
3. Department
of Electronic and Electrical Engineering, University College London, Torrington Place, London WC1E 7JE, United Kingdom
4. Department
of Chemistry, Cambridge University, Lensfield Road, Cambridge CB2 1EW, United Kingdom