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Heavy metals can easily contaminate the aquatic environment, especially shrimp. Considering the high nutritional value of shrimp and the importance of assessing its wholesomeness, this study aimed to determine the amount of some heavy metals (zinc, lead, arsenic, cadmium, nickel, copper, chromium, mercury, manganese, and titanium) and Polycyclic aromatic hydrocarbon in shrimp samples in Tehran, during winter of 2017. A total of 120 samples of shrimp packaged from 10 equal weight packages with similar production date and size which packed by 5 different companies randomly sampled. To determine the amount of heavy metal concentration, Atomic absorption spectrophotometry and to determine polycyclic aromatic hydrocarbon gas chromatography were used. All of the heavy metals measured in this experiment were found below the standard specified by the World Health Organization. The highest mean concentrations of heavy metals were related to zinc (6193.4 ppb), copper (1597 ppb), and arsenic (496 ppb), respectively, and the lowest mean concentrations were related to cadmium (4.8 ppb). Naphthalene (1.2ppb), acenphetylene (0.14 ppb), chrysene (7.6 ppb), and acenaphthene (5.32ppb) were present in the samples of collected shrimp, the values of which were determined higher than standard except for acenphetylene. Additionally, there was no significant difference between heavy metals and PAHs in cultivated and marine samples. In general, the consumption of these shrimps is not dangerous for humans in terms of heavy metals. However, due to the possibility of transmitting PAHs through the human food chain, contamination with PAHs can be considered as a warning for excessive consumption of shrimp.

Background and aims Dentists are occupationally exposed to elemental mercury from placements of mercury-containing amalgam. Although many studies have been conducted on mercury intoxication, there is still widespread concern about possible ill effects of chronic low-level mercury exposure on dentists. The present study examined the effects of occupational exposure to low levels of mercury by a group of dentists. Methods In this historical cohort study, subjects consisted of 106 dentists and 94 general practitioners (referent group), from private and public clinics in Shiraz city. Subjects were requested to complete a questionnaire on demographic variables, symptoms experienced and work practices. Additionally, using standard methods, atmospheric and urinary concentrations of mercury were measured. The data were analyzed by appropriate statistical tests. In univariat analysis, Chi-Square test was used to compare the prevalence of symptoms among both groups. Independent sample t-test and Mann-Whitney’s U-test were used to compare the mean and median of quantitative data of both groups. Multivariate logistic regression analysis was used to adjust for potential confounders. Results Both groups were similar as far as most demographic and socioeconomic variables, but age and number of personal amalgam fillings, were concerned. Median of atmospheric concentration of mercury was found to be 3.35 μg/m3. Likewise, the urinary concentration of mercury in dentists was estimated to be 3.22 μg /g.creatinine. This value was significantly higher than that of the referent group. Additionally, analysis of the data revealed that subclinical symptoms of intoxication were more prevalent in dentists. Conclusion Our findings indicate that occupational exposure to mercury by dentists, even at low levels, is associated with a significant increase in the prevalence of subclinical symptoms of intoxication.

This study was carried out to identify transdiagnostic and diagnosis-related role of Big Five personality factors in predicting adolescents’ risky behaviors. This research had a causal-comparative design and its population comprised senior secondary school students in Isfahan. For the purpose of sampling, multi-stage cluster sampling method was utilized and 1200 high school students were selected. Then, four groups of students with risky behaviors of violence, smoking, alcohol consumption and relationship with the opposite sex were identified based on their scores on Iranian Adolescents’ Risk-Taking Scale. In the next step, a semi-structured interview was conducted and NEO-FFI Inventory was also given to the subjects. To identify the patterns of transdiagnostic and diagnosis-related model, multivariate analysis of variance and discriminant analysis were utilized. The results showed that conscientiousness functioned as a transdiagnostic factor in the four groups with risky behaviors. Furthermore, neuroticism, extraversion, openness to experience, and agreeableness were diagnosis-related factors. The results of discriminant analysis showed that the participants were properly classified into the four groups. Some components, such as conscientiousness were transdiagnostic and can play a significant role in the onset and maintenance of risky behaviors. Hence, the aforementioned constructs could be used in the design of educational and therapeutic interventions since they may contribute to comorbidity through shared (transdiagnostic) processes.

The purpose of the present study was to predict high school teachers’ emotional intelligence based on their attachment styles (Close, Depend, and Anxiety Dimensions). To this end, 80 high school teachers were selected through convenience sampling method in Tabriz. The participants completed Trait Meta-Mood Scale (Salovey et al., 1995) and Revised Adult Attachment Scale (Collins, 1996). The results of correlation analysis showed that components of emotional intelligence (emotional attention, emotional clarity, and emotional repair) were associated with teachers’ attachment styles (Depend and Anxiety). Results of multiple regression analysis demonstrated that anxious attachment style in teachers was the only predictor of the components of emotional intelligence (attention, clarity, and repair). Teachers with dependent attachment style (trust in others) reported higher emotional intelligence and teachers with anxious attachment style reported lower emotional intelligence. Result of the study indicated that the components of teachers’ emotional intelligence can be predicted on the basis of their attachment style; hence, individuals’ emotional intelligence is closely correlated with their attachment style. The practical implications of the study for treating mental disorders are discussed in the paper.

Introduction: Gasoline is a complex mixture of more than 500 various hydrocarbons. The elimination of lead from petrol has been associated with the production of significant amounts of hepatotoxic and nephrotoxic monocyclic aromatic hydrocarbons such as benzene, toluene and xylene (BTX). The main purpose of this study was to ascertain whether or not exposure to unleaded petrol, under normal working conditions, is associated with any hepatotoxic or nephrotoxic response. .Materials and Methods: This was a retrospective cohort study in which 200 subjects with current exposure to unleaded petrol working in Shiraz petrol stations as well as 200 unexposed employees were investigated. Using standard methods, atmospheric concentrations of BTX were measured. Additionally, blood and urine samples were taken from subjects for routine biochemical tests of kidney and liver function. .Results: The geometric means of airborne concentrations of BTX were found to be 0.24, 0.37 and 0.64 ppm, respectively. The result of blood chemistry tests showed that means of direct bilirubin, ALT, AST, urea and plasma creatinine were significantly higher in exposed subjects than in unexposed employees, although all of these parameters were in the normal range. Conversely, serum albumin, total protein and serum concentration of calcium and sodium were significantly lower in petrol station workers than in their unexposed counterparts. .Conclusions: The average exposure of petrol station workers to BTX is lower than the current TLVs for these chemicals. However, clinical significance and long-term results of observed changes in liner and kidney of exposed workers needs more evident in comparison with unexposed group.

In this paper, the nonlinear-non-elastic behavior of the braced frames of the SCBF Special Center is compared with the BRBF anti-arc bracing brackets. Different structures with different numbers of floors, which were previously designed according to the existing regulations and the recommended behavior coefficient, were non-linear static analysis by OPENSEES software and their load-bearing and cyclic behavior were determined for both types of braces. The effect of stiffness strain percentage and the degree of initial geometric defect of the brace on the behavior of the structures were also investigated. Comparison of results indicates more formable and stable behavior of anti-buckling brace than normal brace. Also, the effect of primary geometric defect is significant only in the initial steps of displacement and the higher the percentage of strain strain strain, the more stable behavior structure against larger forces. it shows.

Recently, capture-recapture studies have been used and researchers tend to use these studies in the health field. Therefore, we discussed the basic concepts of these studies. First, we described capture-recapture studies. Then, the important assumptions and calculations were presented according to the close population assumption. Statistical formulas were presented for two-capture methods and dependency between the two lists was discussed. Then, we addressed more than two capture methods.