BACKGROUND The association between overtime work and depression is still unclear. This study examined the association between overtime work and the onset of a major depressive episode (MDE). METHODOLOGY/PRINCIPAL FINDINGS Prospective cohort study with a baseline examination of working hours, psychological morbidity (an indicator of baseline depression) and depression risk factors in 1991-1993...

We consider the problem of minimizing daily expected resource usage and overtime costs across multiple parallel resources such as anesthesiologists and operating rooms, which are used to conduct a variety of surgical procedures at large multi-specialty hospitals. To address this problem, we develop a two-stage mixedinteger stochastic dynamic programming model with recourse. The first stage allo...

To ascertain the usefulness of a 21-item checklist that assesses accumulated fatigue due to overwork, we examined (1) the associations between overtime work, job stressors, or the quantity of sleep/rest and subjective symptoms of fatigue, and (2) whether sleeping hours and monthly days off are associated with the accumulated fatigue parameter using the checklist. Questionnaire surveys were admi...

The aim of this study was to clarify the association between sleeping time and job stress in male Japanese workers. Male workers at one manufacturing plant were surveyed about job stress and sleeping time using a selfcompleted questionnaire. A total of 274 white-collar daytime workers were analyzed. Job stress factors and stress response were assessed using the Job Stress Questionnaire. Sleepin...

Since the development of early versions of material requirements planning (MRP) systems, it has been known that a weak link in this technique is the failure to consider the available capacity at the time the lot sizes for individual items are calculated. Ignoring the available capacity may result in infeasible production plans i.e., those that can only be accomplished with the use of overtime. ...