thorough knowledge of the morphology and internal anatomy of the root canal system is essential, because it determines the successful outcome of endodontic treatment. the main goal of endodontic treatment is to prevent apical periodontitis and/or to promote the healing of periapical lesion. presence of two canals or roots on the palatal side of the first maxillary molar has rarely been reported...

acquaintance with the different anatomical variations of the arterial supply of the gallbladder is of great importance in hepatobiliary surgical procedures. a rare variation of the hepatobiliary arterial system was found during anatomical dissection of a female iranian cadaver. two cystic arteries were present, the first arising directly from the right hepatic artery and the second from the gas...

introduction: the brachial plexus is responsible for the innervation to the upper limb and some parts of the thorax. variations in the branching of the brachial plexus are common and have been reported in 65.3% of the population. the variations (atypical communication) of brachial plexus have significant clinical and surgical importance. methods: in this study 10 upper limbs which belonged to 5...

conclusions because the intestinal parasitic infections are a health concern in areas with poor nutritional and socioeconomic status, intervention programs, including health education and environmental sanitation, are required. background intestinal parasitic infections are one of major health problems, especially in developing countries. several factors, such as geographical location and socio...

background and objective: obstructive sleep apnea (osa) is the most common respiratory disorder during sleep and a risk factor for myocardial ischemia. in this study, we evaluated the proportion of subjects at high risk for osa and prevalence of its predictors among patients admitted for acute myocardial infarction (mi). materials and methods : a total of 210 patients with mi admitted at the ca...

vehicle exhaust is a major source of exposure to polycyclic aromatic hydrocarbons (pahs) found in the urban atmosphere. newsagents usually work close to heavy traffic flow. the purpose of this study was to assess the breathing zone exposure of newsagents to pahs found in the urban atmosphere of tehran city during summer and autumn seasons and comparing the levels of exposure in both seasons.fif...

in this paper, the concept of conjectural variation (cv) is used to specify optimal generation decision for generation companies (gencos). the conjecture of genco is defined as its belief or expectation about the reaction of rivals to change of its output. using cv method, each genco has to learn and estimate strategic behaviors of other competitors from available historical market operation da...

external fluted feed rolls are commonly used in grain drills. the fluted feed roll meters a volume of seeds and does not singulate the seeds as do the precision planters; therefore, there will be inherent variation in the number of seeds delivered per unit of time. this research was conducted to investigate the effect of seed meter drive shaft and ground speeds and outlet positions in a grain d...

one of the main distinctions between geomaterials and other engineering materials is the spatial variation of their properties in different directions. this characteristic of geomaterials -so called heterogeneity- is studied herewith. several spatial distributions are introduced to describe probabilistic variation of geotechnical properties of soils. among all, the absolute normal distribution ...