this study was undertaken to define the prevalence of the upper gastrointestinal (gi) lesions, dyspeptic symptoms, h.pylori infection, and the impact of duration of dialysis on upper gi symptoms and lesions of children with end-stage renal disease. we studied 69 children with esrd who were under regular hemodialysis therapy in our department. the age of the patients were between 4-18 years (mea...

chainsaw is an important machine for tree felling limbing and bucking in hyrcanian forest and the major problems related to using forest machines was sound intensity. the aim of this study was to measure the sound level in occupational exposure of workers, determine the exposure time of workers and comparison of the variables among the workers. this study was carried out in namkhaneh district i...

  A novel optimal single machine replacement policy using a single as well as a two-stage decision making process is proposed based on the quality of items produced. In a stage of this policy, if the number of defective items in a sample of produced items is more than an upper threshold, the machine is replaced. However, the machine is not replaced if the number of defective items is less than ...

frasnian - famennian boundary in the kal-e-sardar section (east of tabas, central iran) is investigated on the basis of conodonts. distribution of thirty-three species and subspecies in the stratigraphic column enables us to recognize a barren interval and five biozones; upper rhenana, upper part of upper rhenana - linguiformis, lower to middle triangularis, upper triangularis, lower crepida. b...