we propose to use a mathematical method based on stochastic comparisons of markov chains in order to derive performance indice bounds‎. ‎the main goal of this paper is to investigate various monotonicity properties of a single server retrial queue with first-come-first-served (fcfs) orbit and general retrial times using the stochastic ordering techniques‎.

objectivet: to determine the prevalence and risk factors of postpartum depression among women living in zabol, a city in south-east of iran. method: 2 to 8 weeks after delivery, 408 women were assessed for depression and some of its risk factors. results: the prevalence of postpartum depression was (40.4 %). risk factors for the onset of post-partum depression included younger age, low income f...