No abstract

We have carried out chemical shift perturbation titrations on three contrasting proteins. The resulting chemical shifts have been analysed to determine the best way to fit the data, and it is concluded that a simultaneous fitting of all raw shift data to a single dissociation constant is both the most accurate and the most precise method. It is shown that the optimal weighting of 15N chemical shifts to 1H chemical shifts is protein dependent, but is around the consensus value of 0.14. We show that chemical shift changes of individual residues can be fit to give residue-specific affinities. Residues with affinities significantly stronger than average are found in close contact with the ligand and are suggested to form a rigid contact surface, but only when the binding involves little conformational change. This observation may be of value in analysing binding and conformational change.

The characteristic of a new form of high strength polymer grid are outlined and its possible uses as reinforcement in concrete subjected to dynamic loading are discussed. Details are given of a test programme in which concrete slabs reinforced with a range of grid types in various configurations have been subjected to explosive loading from contact charges of plastic explosive. A range of both transient and post-test measurements were taken. Results are presented showing how the various damage parameters measured vary with the position and number of polymer grids used in the slabs. The results of the transient measurements are used to suggest mechanisms for damage formation. It is concluded that these polymer grids are effective in restraining explosively generated damage in concrete slabs and that in many circumstances their light weight and their inherent resistance to normal corrosion processes may give them significant advantages over conventional steel reinforcement.