Affiliation: | (1) the E. M. Centre, Chemistry Building, Glasgow University, G12 8QQ Glasgow, UK;(2) the Department of Agricultural Sciences, University of Wales, Penglais, SY23 3DD Aberystwyth, Dyfed, UK;(3) the Department of Biological Sciences, University of Wales, Penglais, SY23 3DD Aberystwyth, Dyfed, UK |