AIM To document the prevalence of perturbations of handover meetings and understand how nurses manage temporal, physical and social meeting boundaries in response to perturbations. BACKGROUND Handovers are joint activities performed collaboratively by participating nurses. Perturbations of handover are frequent and may potentially threaten continuity of care. DESIGN We observed and videotap...

We derive a time-dependent exact solution of the free surface problem for the Navier–Stokes equations that describes the planar extensional motion of a viscous sheet driven by inertia. The linear stability of the exact solution to oneand two-dimensional symmetric perturbations is examined in the inviscid and viscous limits within the framework of the long-wave or slender body approximation. Bot...