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Today, Phased Array Ultrasonic Testing (PAUT) is a suitable method for detecting defects in Non-destructive Testing (NDT). This simulation was done with a new method on a stainless steel pipe with a diameter of 500 mm and a length of 1,000 mm, and cracks were modeled on the external and internal surfaces and corrosion defects on the internal surface. Four probes with a characteristic of 2 MHz were used simultaneously, each probe having 64 elements. By increasing the number of probes and their elements, more accurate information about the defects is obtained, which makes it easier to detect the location and leads to a reduction of scattered signals and noise, which can detect even small size defects. Considering this important advantage, a new use of the method of increasing the number of probes in PAUT is reported in this study to detect defects, especially corrosion defects. The results of geometric anisotropy studies of group velocity and phase of horizontally polarized shear waves (SH-waves) for stainless steel pipe were presented. Due to the isotropic properties of the pipe material, the speed on the outer surface of the pipe in the direction of the cover is 40 m/s higher than the generatrix.

Introduction: Manual Material handling includes activities in which pushing, pulling, lifting, lowering, carrying, and holding the load, the most common of which is lifting. This study aimed to evaluate the reliability of the KIM-LHC method to identify high-risk manual load lifting tasks. Material and Methods: This cross-sectional study was performed on healthy male workers with a history of manual material handling in a laboratory setting. The sample size was determined according to previous studies of 15 people. The participants were required to perform 25 tasks with four iterations randomly. An inclinometer device was used to determine the forward bending angle at the waist. Compression loads exerted on L5/S1 were estimated using 3DSSPP software using participants' postural and anthropometric information. Also, the tasks were evaluated using the KIM-LHC method, and their final scores and levels of MSD risks were determined. Data were analyzed using SPSS.20 software and the Chi-square test. Results: The results of compression load estimation for lifting tasks showed that 92% of the tasks had a low-risk level (less than 3400 N), and 8% of the tasks had a medium-risk level (3400 to 6800 N). While the results of the KIM-LHC method showed that 28% of tasks had a low-risk level, 64% had a medium level, and 8% had a high-risk level. Conclusion: The results of this study showed no correlation between the risk levels of the KIM-LHC method and the estimated compression load for some designed lifting tasks. Therefore, there is a possibility of error in estimating the risk level of some lifting tasks by the KIM-LHC method, and more biomechanical studies should be performed on kinetics and kinematics.

Introduction: Work-related musculoskeletal disorders are the most common and costly preventable occupational problem that office workers suffer from the discomfort associated with these disorders. The aims of this study were to a) investigate the prevalence of low back pain (LBP) and b) continuously assess the trunk postures of office workers .Materials and Methods: Thirty-six office workers of a medical university participated in this cross-sectional study. Thirty-six office workers of a medical university participated in this cross-sectional study. The prevalence of LBP was determined using the Nordic Musculoskeletal Questionnaire. Work trunk postures were measured using an inclinometer. Results: More than half of the subjects reported LBP. There was a significant relationship between LBP with age, work experience, working hours, and gender (p

Introduction: Work-related musculoskeletal disorders are among the most common diseases that cause absenteeism and disability. Exposure to ergonomic risk factors in construction workers increases the risk of discomfort and musculoskeletal disorders in this group. The present study investigates occupational and individual factors predicting musculoskeletal disorders and pain disabilities in construction workers. Material and Methods: The present cross-sectional study was conducted on 346 construction project workers in Tehran. To study the prevalence of musculoskeletal discomfort, job stress, and pain disabilities, Cornell Musculoskeletal Discomfort Questionnaire, Job Content, and Pain Disability questionnaires were used. Results: The results of the present study showed that the highest rates of musculoskeletal discomfort were in the neck (68%), left knee (64%), right knee (86%), and back (61%), respectively. The mean score of pain disability was 35.43 ± 20.18, and 16% of people were in severe disability. The results showed that with increasing work experience, working hours per day and body mass index of pain disability increases, and age, work experience, body mass index, and the component of physical needs of the job are the contributing factors of the musculoskeletal discomforts. Conclusion: Musculoskeletal disorders and pain disability were high in the studied construction workers. Based on the results, age, work experience, body mass index, and job stress contributed to musculoskeletal disorders and pain disabilities. Therefore, this study's results can help to understand better the risk factors affecting musculoskeletal disorders and pain disabilities in construction workers.

Introduction: Resilience is one of the competencies that enable nurses to adapt to stressful risk factors at work and demonstrate a healthy and stable psychological performance. The present study aimed to investigate the predictive role of resilience on job stress among Iranian nurses. Methods: The current cross-sectional study was conducted in Ahvaz, Iran, with participation of 200 nurses in May 2019. Participants were recruited via stratified random sampling. The resilience indicators and job stress data were collected by the Connor–Davidson Resilience Scale and OSIPOW Job Stress Questionnaire. Results: The results showed a significant negative correlation between resilience and job stress (r = −0.824, P < 0.05). Similarly, a significant linear regression existed between job stress and resilience (β = −0.824, P < 0.05) in such a way that resilience predicted 67.9% of the job stress variance in the participants (R2 = 0.679). In addition, it was revealed that the multi-aspect model could significantly predict job stress based on linear resilience indicators (P < 0.05). Conclusion: The results indicated that resilience indicators have a significant relationship with job stress, and this relationship can be used to predict changes in job stress based on resilience. Therefore, it is strongly recommended that resilience improvement programs should be developed and implemented for nurses.

Background: The trans-theoretical model is a model that is very sensitive to changes in the minor progress of behavior. Therefore, the trans-theoretical model is more practical than other patterns of behavior change, which have been considered all or no to measure physical activity. This study aimed to standardize and determine the validity and reliability of the tensile movement questionnaire at the University of Medical Sciences employees. methods: In this study, after searching the texts and the study of the same questionnaires and tools and among the available and related tools, the initial questionnaire was designed. First, the validity and content of the questionnaire were measured using expertschr('39') comments. Then, the ability to understand the questionnaire based on the opinions of 10 employees was investigated. Finally, to determine the reliability with the experimental-open test method, 30 employees, Cronbachchr('39')s alpha, and the correlation coefficient were obtained using SPSS software. Results: After performing the necessary reforms with expertschr('39') opinions, finally, the questionnaire with increasing the number of questions of the field of self-efficacy from 6 to 7 questions, the reduction of the number of questions of the interests of stretching movements from 10 to 5 questions, increasing the number of questions of the barriers of stretching movements from 4 to 7 questions and increasing the number of questions of In the validation stage, each 40 of the questions had acceptable content validity (8.0 to 99.0). Also, at least 80% of the questions were diagnosed in terms of the target group acceptable. Cronbachchr('39')s alpha coefficient and correlation coefficient were 86.0 and 7.0, respectively. Conclusion: A designed questionnaire based on the trans-theoretical model constructs to assess educational intervention to enhance the tensile movements of employees has acceptable reliability and validity.

Background: In the face of COVID-19, healthcare workers need to cope with the ongoing stressors at play and keep psychological distress at a minimum level. This study examined the psychosocial and demographic factors associated with nurse's resilience in the hospitals of Ahvaz that is one of the top cities infected with COVID-19 in Iran.Methods: The present cross-sectional study was conducted on 387 Iranian nurses in Ahvaz city. For data collection purposes, three online questionnaires (including Copenhagen Psychosocial, Demographic, and Connor–Davidson Resilience Scale) were distributed among the participants.Results: The mean resilience score was equal to 61.8 ± 14.8 for 387 nurses. Resilience had a statistically significant negative correlation with quantitative demand (r = −0.273, P < 0.008), work pace (r = −0.262, P < 0.011), emotional demand (r = −0.226, P < 0.030), stress (r = −0.458, P < 0.000), and burnout (r = −0.287, P < 0.005). Multiple linear regression analysis indicated that stress, job satisfaction, burnout and age were the main predictors of nurses' resilience during the (COVID-19) pandemic (R2 = 0.45).Conclusions: We identified psychosocial and demographic predictive factors that may contribute to greater resilience among nurses during the COVID-19 outbreak. The findings of this study can be used to implement psychosocial interventions to amplify the resilience of medical staff during the COVID-19 outbreak.

The purpose of this study is to investigate the effect of resistance spot welding (RSW) parameters on nugget size and ultimate strength of Magnesium alloy sheets AZ61 under tensile-shear test. In this study microstructural examination and hardness measurements were carried out on the welded samples. The results show that the weld nugget zone is divided into two separate parts: the equiaxed dendritic zone (EDZ) perched at the center of the weld nugget and the columnar dendritic zone (CDZ) situated around the fine-grained zone having it surrounded. The effect of the following three parameters: electric current, welding time and electrode force on the dimensions of the weld nugget and the welded ultimate strength is investigated. The response surface method (RSM) is employed to examine the effects of welding parameters and to attain optimum parameters. The analysis of variance (ANOVA) results of RSM model shows that however the tensile-shear strength and nugget size are improved with increasing the welding current and welding time, the welding current is the most influential parameter. In addition, the optimal values for the welding parameters are calculated to achieve the maximum nugget size and the ultimate strength of welded joint. Finally, a regression model is proposed in order to predict the peak load and the nugget size as function of the mentioned welding parameters.

In industry and developed societies, annual work accidents can bring about huge losses. By proper analysis of these events, the development of controlling measures can be the most important action to prevent similar events and enhance the health of the society. Hence, the current study was aimed at analyzing a case of occupational accidents leading to death in one of the car industries. This qualitative case study was conducted in spring, 2018. With the implementation of Systems Theoretic Accident Model and Processes (STAMP), the incident statement had been described accurately and, then, a safety control structure has been designed to determine inadequate effective safety control actions in the event of an accident. In the analysis of the incident, various factors were involved at different levels of incident hierarchy where the various components of socio-technical systems interact with each other; the inadequate control action of the safety unit was more prominent. Based on the STAMP technique, unlike traditional methods, does not consider the cause of the accident just a component of failure or malfunction of the system. Therefore, it provides a useful tool in incident analysis, especially in complicated and sensitive systems.

Background: The present study aimed to evaluate the biomechanical exposure to the trapezius muscle activity in female weavers for a prolonged period in the workstation A (suggested by previous studies) and workstation B (proposed by the present study). Methods: Electromyography data were collected from nine females during four hours for each ergonomically designed workstation at the Ergonomics Laboratory, Hamadan, Iran. The design criteria for ergonomically designed workstations were: 1) weaving height (20 and 3 cm above elbow height for workstations A and B, respectively), and 2) seat type (10° and 0° forwardsloping seat for workstations A and B, respectively). Results: The amplitude probability distribution function (APDF) analysis showed that the left and right upper trapezius muscle activity was almost similar at each workstation. Trapezius muscle activity in the workstation A was significantly greater than workstations B (P