  In the preceding paper, we developed an athermal shear-transformation-zone
(STZ) theory of amorphous plasticity. Here we use this theory in an analysis of
numerical simulations of plasticity in amorphous silicon by Demkowicz and Argon
(DA). In addition to bulk mechanical properties, those authors observed
internal features of their deforming system that challenge our theory in
important ways. We propose a quasithermodynamic interpretation of their
observations in which the effective disorder temperature, generated by
mechanical deformation well below the glass temperature, governs the behavior
of other state variables that fall in and out of equilibrium with it. Our
analysis points to a limitation of either the step-strain procedure used by DA
in their simulations, or the STZ theory in its ability to describe rapid
transients in stress-strain curves, or perhaps to both. Once we allow for this
limitation, we are able to bring our theoretical predictions into accurate
agreement with the simulations.
