this study investigates propagation of mode i crack in b70 pre-stressed concrete sleepers by fracture mechanics approach. a new experimental analysis is done for notched b70 pre-stressed concrete sleepers with replica test and image analysis. a scanning electron microscope test (sem) and an image analysis are applied for the replica test in order to determine crack length and crack mouth openin...

initial cracks occur in high strength concrete sleepers for various reasons, such as shrinkage and wrong curing and long lifetime of over 50 years of sleepers. these cracks may lead to complete failure of the structure. in order to more accurately design the sleepers, fracture mechanics (not strength of materials) should be incorporated. in order to achieve this purpose, it is important to fore...

introduction: cloacal malformation is an extremely rare fetal pathological condition but an important anomaly that presents as a variety of defects. it predominantly affects females, with prevalence of 1 in 50,000 births. prenatal ultrasonography usually showed oligohydramnios and the fetus having a large cystic mass in the lower abdomen with a single septum, bilateral hydronephrosis, ambiguous...

The basic task of the work was to conduct research aimed at studying technical condition track and its impact on rolling stock since car dynamics, especially in curves mountain pass sections track, is completely dependent deviations. real time data received from specialized laboratories show existence deviations visually detected, however external are not crucial main problem lies inside struct...

Study Objectives To describe sleep duration patterns of adults over a 20-year period; to compare sociodemographic, lifestyle, and health characteristics across these patterns; and to relate the patterns to sleep quality. Methods The study population consisted of 3695 adults aged 20 to 59 years at baseline. Five measurements of self-reported sleep duration were used to compose seven patterns f...

Frank Sohn, on whom the following observations were made, was a hypnotic subject of Mr. Santanelli, a professional hypnotist. The boy had become so subjective that Mr. Santanelli proposed to keep him in a continuous hypnotic sleep for a week, without food or drink, and to use the seven-days sleeper as an additional attraction for his nightly exhibitions of hypnotism. Only two days before the ex...

background and aims. the objectives of the present study were to investigate the prevalence and the position of enamel defects of primary teeth and hence to estimate the approximate time of an insult. material and methods. 121 children aged 3 to 5 years were included in the study. the modified developmental defects of enamel index was used to diagnose and classify the defects. the defects were ...