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These days, most of the marine structures which are constructed and used in Persian Gulf, are made of ST37 steel. Due to oil and gas sources excavated, the number of these structures is constantly increasing. On the other hand, these types of structures are exposed to corrosive environments and it is seriously critical for these structures to be used for many years. Coal tar epoxy (trade name), one of the popular coating layers, is used in different parts of steel constructions which are in use in the Persian Gulf. Several works have been carried out on the functioning quality of this coating in tidal zones, under splashing water and atmospheric conditions, but up to now no report is made in submerge zone. Hence in this investigation, three coating systems have been considered that coal tar epoxy is being used in each of one of the three layers of primer, middle and top. Two systems of laboratory and in field have been investigated for 6 months and an isolated system in field type has been also investigated. All the mechanical and chemical tests which have been performed are according to NACERPO176-64 standard which is for investigating the function of all marine coatings. All corrosion tests have been performed in Refinary Laboratory of Petroleum Industry and all the fields samples have been investigated in Steel Harbor located in the south of Bandar Abbas every week during 6 months. The test results have indicated that the coal tar epoxy which were being used in the last layer is not suitable for submerge zone. By preparing, however, a suitable surface in the first layer using zinc ethyl silicate and the last layer with antifouling, the coal tar epoxy can function properly in the middle layer.

Background and Objectives: Given that no comprehensive studies have yet been conducted on treatment of infectious wastes in hospitals of Qom City, this research was performed with the purpose of investigating the treatment methods used in these hospitals and monitoring the performance of waste elimination devices. Methods: Required information was obtained through in-person visit and observing the current situation, and the variables affecting waste treatment were extracted based on the type of treatment systems, and were collected, and accordingly, biological monitoring tests were designed for the studied hospitals. The data were analyzed using Fisher's exact test. Results: In this study, from 9 active hospitals in Qom Province, only 3 hospitals were equipped with waste treatment system. In hospital A, growth of Bacillus stearothermophilus spore were observed in 6.25% of the samples, while no microbial growth was recorded in hospital B. The initial investment to buy the machine in hospital A was about four times than that of hospital B. Conclusion: The findings of this study showed that treatment device of hospital B is more appropriate compared to the devices of hospital A due to complete destruction of spores, lower cost (for purchase), and maintenance. .

Introduction: Pain and overuse injuries of the knee joint is prevalent among cyclists. The bicycle adjustment in accordance with the cyclist’s body mechanics is a common way to reduce the risk of overuse injuries. The aim of this study is to investigate the effect of changes in bicycle pedal width on the kinematics of segments and joints of lower extremity and its association with the risk of knee overuse injuries during pedaling. Materials and Methods: 10 professional cyclists of Shiraz City, Iran, pedaled at 100% of maximum power output with four different pedal widths (Q0: conventional pedal width, Q1: Q0 + 1cm, Q2: Q0 + 2cm, and Q3: Q0 + 3cm). The angle of the lower extremity segments and joints was recorded three dimensionally for thirty seconds during pedaling in each pedal width by myoMotion system. The minimum, maximum, and mean angles and range of motion (ROM) variables of hip and ankle (sagittal plane), knee joint (sagittal and frontal planes), and thigh and shank angles in the frontal plane were calculated. One-way repeated measures analysis of variance (ANOVA) and Bonferroni post-hoc test were used to identify significant changes. Results: The statistical results showed that changes in the pedal width had a significant effect of on minimum (P = 0.035), maximum (P ≤ 0.042), and mean (P ≤ 0.020) of shank abduction/adduction and minimum (P = 0.015), mean (P ≤ 0.022), and ROM (P ≤ 0.018) of ankle dorsiflexion/plantar flexion, while changes in the pedal width had no significant effect on other kinematics parameters. Conclusion: The results indicate that pedal width of Q1 has the highest potential to lower the risk of knee injury and provide increased efficiency whilst cycling; Still, the standard pedal width of road bikes (Q0) seemed not appropriate for professional Iranian cyclists since it increases the risk of knee joint overuse injuries.