No abstract

Direct measurement of the depletion interaction between electrically charged surfaces has been obtained using the optical technique of total internal reflection microscopy (TIRM). The long-range interaction between a polystyrene sphere and a polished glass plate was measured in aqueous solutions of non-adsorbing colloidal silica particles (all surfaces were negatively charged). The measured potential-energy profiles displayed a repulsive potential at large separations, followed by a depletion attraction at closer distances. At increasing silica concentrations, evidence of a long-range oscillatory behaviour was observed.Comparison of the measured energies to those predicted using a force-balance model indicate that the non-adsorbing silica particles contribute slightly to the screening of the electrostatic interaction between the polystyrene particle and plate. Adjustment for this screening produces good agreement between theory and experiment.

No abstract

No abstract

The incidence rates are similar to other studies from India. Stroke patient survival is poor in public hospitals. The finding of spatial analysis is of public health significance for stroke prevention and strengthening of stroke services.