Subjective accommodation refractive error models are essential for implementing adaptive vision correction devices that utilize varifocal optics. This article describes compact empirical of subjective accommodative errors in subjects with advanced presbyopia. The based on measurements from fifteen presbyopes over the age 45 using commercially available focus-tunable eyeglasses under three diffe...

We use an analog of nanoindentation on a colloidal glass to elucidate the incipient plastic deformation of glasses. By tracking the motion of the individual particles in three dimensions, we visualize the strain field and glass structure during the emerging deformation. At the onset of flow, we observe a power-law distribution of strain indicating strongly correlated deformation, and reflecting...

A high drop-out rate prior to the running of a Marathon reduces its value as a spectacle and needlessly causes rejection and antagonism amongst potential runners. This research investigates reasons for pre-race drop-out in the 1983 Glasgow Marathon, and finds that a major cause was injury or illness during training, with a motivational difference existing between runners and non-runners.