some researches made in the field of agency problem issue, deal with the role of control systems regarding owners and managers. in this research the relationship between the two control mechanisms, namely the voluntary disclosure (external control mechanism) and outside directors (internal control mechanism), which are reductive of agency problems, has been studied. for this reason, a sample ...

Iron, one of the essential micronutrients, is needed for electron transport and metabolic processes in almost all living organisms. The ferric form (Fe3+) of iron is insoluble in nature and inaccessible at physiological pH (7.35–7.40). Under iron-limited conditions, metal-chelating agents such as siderophores are synthesized by many bacteria and a few fungi. Siderophores have a high affinity fo...

nanotechnology is a general term which is related with field of all advanced science term that generally predicates with all modern technologies which consider nanoscales. improvement in the quality of products by adding some nanoparticles and study of their behavior in the presence of these nanoparticles have been obtained in many researches. on the other hand numerous demands for sowing ...

power transformers are important equipments in power systems. thus there is a large number of researches devoted of power transformers. however, there is still a demand for future investigations, especially in the field of diagnosis of transformer failures. in order to fulfill the demand, the first part reports a study case in which four main types of failures on the active part are investigate...