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Introduction: Legionella Pneumophila bacteria is known as one of the most important nosocomial infections and the most common cause of death in patients. This study was aimed to identify Legionella Pneumophila bacteria in hospital water supply systems. Material and Methods: This descriptive cross-sectional study was performed to identify Legionella pneumophila in hot and cold-water systems of important and sensitive wards of Imam Khomeini Hospital in Divandareh city (neonatal, dialysis, obstetric, gynecological and menchr('39')s surgery). A total of 60 samples were collected from these sections. Results: According to the results of this study, a total of 17 (28%) of all samples were infected by Legionella pneumophila bacteria in water supply systems including hot showers and cold water in neonatal, dialysis, delivery, surgery. gynecology and menchr('39')s surgery wards were identified. Conclusion: Lack of proper water treatment system, low residual chlorine content, and presence of biofilm in water supply system and proper temperature range of growth with this bacterium could be the major causes of Legionella contamination in the studied hospital.

Background and aim: Water supply systems and various parts of dentistry unit have the ability to aggregate biofilms and thus the transmission of dangerous diseases to staff and patients. The aim of this study was to determine the bacterial contamination of surfaces and water lines of dental units of health center (Qods 2) in Divandareh city. Material and methods: This cross-sectional descriptive study was conducted on dental units of the health center (Qods 2) in Divandareh city in 2019. 125 samples were collected from different parts of the units including unit lamp handle, lamp ON/OFF power button, open/close bolt of unit water, setting switch button (before and after disinfecting), and the inlet and outlet water of units. The samples were tested for Staphylococcus aureus, Pseudomonas aeruginosa, Coliforms and Escherichia coli. Results: The results of this study showed that all samples collected from the studied parts of the units including unit lamp handle, lamp ON/OFF power button, open/close bolt of unit water, and setting switch button were positive as presence of Staphylococcus aureus, Pseudomonas aeruginosa, and coliforms before and after disinfection. Also, the unit lamp handle and setting switch button were positive as Escherichia coli. The inlet and outlet water were also positive for all the studied bacteria. The number of Staphylococcus aureus bacteria in the handle of the unit lamp before disinfection (210±80.5 CFU/ml) and in the ON/OFF button of the lamp after disinfection (300±82.6 CFU/ml) were higher than the permissible amount (200 CFU/ml). Also, the number of Pseudomonas aeruginosa bacteria detected in setting switch button, before disinfection, was higher (200±75.2) than the allowable value. Conclusion: According to the obtained results, the contamination level of water and surface of the studied dental units was high. Also, identifying of the considerable number of bacteria at the different surfaces of the units, indicating the improper use of the disinfectants and the possibility of biofilms presence in the unit waterlines.

Background and objectives: Construction is one of the most dangerous industries in the world and one of the authorities’ concerns of officials in this area is to improve their safety. This study was carried out so as to investigate the causes of unsafe behaviors in a combined cycle power plant. Materials and Methods: In this cross-sectional study, a questionnaire for 300 workers of the combined cycle power plan were used. The obtained information was divided into criteria and sub-criteria affecting the causes of unsafe behaviors. Criteria and sub-criteria were distributed as a pairwise comparison questionnaire among 19 people who worked on the safety and they were supposed to answer based on their experiences as well as the distance scale. Criteria and sub-criteria were ordered by Analytic Hierarchy Process (AHP) and using Expert Choice‌ software. Results: the results showed that the criterion of individual characteristics (34 %) is the most effective factor for unsafe behaviors and followed by employer (22%), teaching 915%), education (12%), specialization and experience (7.8%), age (7.6%), job characteristics (3%), and weather condition (2%) respectively. Conclusion: the most important sub-criterion of individual characteristics is a onechr('39')s susceptibility to accident. Hence, it is necessary to prevent unsafe behaviors by employing vulnerable people in less dangerous occupations.

Background: The discharge of a large volume of colored wastewater into receiving water sources has caused widespread concern around the world. The aim of this study was to investigate the efficiency of pumice as an adsorbent in removing methylene blue (MB) from aqueous solution. The adsorption process was also modeled and optimized by the methods as follows: central composite design-central composite design (RSM-CCD) and artificial neural network-genetic algorithm (ANN-GA). Methods and Materials: The independent variables in the study were included pH (3-11), contact time (10-50 minutes), adsorbent dose (0.1-2 g/L), and MB concentration (20-100 mg/l). The effect of these parameters on the efficiency of pumice in MB uptake was modeled and optimized by RSM-CCD and ANN-GA methods. A spectrophotometer at 620 nm was used to measure the residual MB concentration in solution. Results: The results showed that the RSM-CCD method has the ability to develop a quadratic polynomial model with high validity (R2 = 0.9997) for the adsorption process. Similarly, the ANN-GA method fitted well with experimental data to develop a model with high validity (R2 = 0.9978). The results of optimization process by RSM-CCD and ANN-GA methods obtained the highest adsorption efficiency at pH = 11, contact time = 50 minutes, adsorbent dose = 1 g/L, and concentration MB = 20 mg/L. Adsorption efficiency shows a direct relationship with pH, contact time and adsorbent dose and inversely with contaminant concentration. The linear effect of pollutant concentration and adsorbent dose variables had the greatest effect on adsorption efficiency. Conclusion: In this study, it was observed that pumice as a cheap and available adsorbent can be considered as a suitable choice for absorbing dye pollutants from aqueous media. RSM-CCD and ANN-GA methods can also be used to model and optimize adsorption processes.

Background and purpose: Styrene, one of the most important compounds of VOCs, causes some health concern. In current study, the ability of ZSM5, TiO2/ZSM5, UV/ ZSM5, and UV/TiO2/ZSM5 methods was investigated in removing styrene from air synthetic current. Materials and methods: In order to synthesize the zeolite and TiO2-coated zeolite, the sol-gel and saturation methods were employed, respectively. In this study, the effect of the type of removal process, saturation time and initial pollutant concentration were investigated on the removal of styrene in a photoreactor. Phocheck device with direct reading system was applied to determine the output concentration. Also, SEM, XRD, EDX, and BET analyses were used to characterize the chemical and physical properties of ZSM5, and TiO2/ZSM5. Results: SEM analysis showed that zeolite has a crystal form, and TiO2 successfully covered the surface of this compound. In addition, the EDX analysis demonstrated that a great part of zeolite structural includes Al and Si constituents. The XRD pattern showed the presence of attached TiO2 in the zeolite structure. BET analysis revealed that the surface area of zeolite decreased when TiO2 was coated on its surface. The order of increase in removal efficiency was as follows: UV/TiO2/ZSM5 > ZSM5> TiO2/ZSM5. The saturation time of ZSM5 and TiO2/ZSM5 in the 300 ppm concentration was 370 and 280 min, respectively, while the outlet concentration in the UV/TiO2/ZSM5 method was fixed at 74% removal efficiency after elapsing 310 min. The increment of time exposure and initial styrene concentration also led to decrease in removal efficiency. Conclusion: In this study application of UV/TiO2/ZSM5 process provided a higher efficiency of the styrene removal than that of TiO2/ZSM or ZSM5 in the same time.

Background and Objectives: Synthetic dyes are an important group of additivesused in food products, and because of health concerns about consuming population, the application of these compounds is needed to be enough controlled. The aim of this study was to investigate the types and frequencies of the dyes used in making pastries in the confectionery of Tuyserkan city. Materials and Methods: In this cross-sectional study investigated the types of consumed dyes in confectionery’s pastries of Tuyserkan city. A total of 80 samples including wet and dry pastries are randomly sampled from 17 confectioneries. The steps of the experiment consisted of degreasing the sample, purification, and determining the type of dye were down by using Tin Layer Chromatography (TLC) method. All charts used in the study were drowned by Excel Software (2013). Results: The results indicate, among the total 80 samples, 17 samples contained no dye, 15 samples with natural dye, 44 samples with permitted synthetic dyes, and 4 samples have non-permitted synthetic dyes. Moreover, of all the synthetic dyes, 8 samples contained Quioline yellow dye, 10 samples with Sanset yellow dye, 8 samples with Azorubine dye, 5 samples with Brilliant blue dye, 5 samples with ponceau 4R, and 4 (5%) samples have Allura Red. Conclusions: This study showed a remarkable part of used dyes in the confectionery of Tuyserkan city is non-permitted. Therefore, it is proposed to reduce the amount of synthetic dyes by restriction in distribution, more controlling by health departments, and increasing the awareness in consumers and manufactures.

Introduction and Aims: Pharmaceutical pollutants in aqueous can cause a number of health problems for people and other creatures. In this study, a survey of Dexamethasone removal from synthetic aqueous solutions was investigated by using UV/S2O8 and UV/H2O2 methods. Materials and Methods: This experimental study carried out at lab scale at a reactor with the batch flow. In this study, the parameters of time (5- 60 min), pH (3, 7 and 11), dose of S2O8 (0.1-7.5 mM), dose of H2O2 (0.1- 7.5 mM), and Dexamethasone concentration (5- 20 mg/L) were studied to specify their effects on Dexamethasone removal. Furthermore, the remaining concentration of dexamethasone was determined by spectrophotometer DR (model 5000) in the 241 nm wavelength. Results: Results showed that with the increasing amount of parameters of pH, retention time, and a dose of H2O2 and S2O8 and with decreasing parameter of dexamethasone concentration, removal efficiency raised. Removal efficiencies of dexamethasone in the optimum condition of time=40, pH=3 and dexamethasone concentration = 5 mM was obtained 47, 59, 82, 91, and 98 percent for UV/S2O8 concentrations of 0.1, 0.5, 1.5, 5, and 7.5 mM, and 19, 49, 61, 65, and 72 percent for UV/H2O2, respectively. Conclusion: According to higher removal efficiencies of UV/S2O8 method than UV/H2O2, easier storage and moderate stability of S2O8 and also more oxidation ability of SO4- than OH°, it is better to apply UV/S2O8 method to degradation of dexamethasone.

Background: Due to their polycyclic and toxic structure, dyes have a high ability in causing adverse acute and chronic effects on human exposed to them. In present study, the decolorization of acid green3 from aqueous solution by UV/ H2O2 method was investigated Methods: This is an applied-experimental study. Parameters of pH in the amount of 3,7 and 11, contact time in 5,15, 30, 45 and 60 min, dose of H2O2 in 10, 30 and 50 mg/l and initial concentration of acid green3 in 50, 100 and 150 mg/l were examined to reveal the optimum amounts of these parameters. In order to emit the UV radiation, photo reactor with a 2-lit volume was applied, also to measure remaining concentration of dye, spectrophotometer device, model DR 5000 was employed. Chemical oxygen demand (COD) test based on 5220C method (standard method book) was used for determining amount of oxidation. Results: Results showed that contact time = 60 min, pH=7, acid green concentration=50 mg/l and dose of H2O2 =30 mg/l are optimum condition at which the removal amounts of dye and COD were obtained about 97 and 85%, respectively. Conclusion: In the study, it is observed that parameters of contact time, pH, initial concentration of dye, and dose of H2O2 have a significant influence on the removal of the dye by UV/H2O2 process. Due to acceptable results of UV/H2O2 in the oxidation of the dye and the reduction of COD, this method can be introduced as reliable process to remove of acid green 3 from industrial wastewaters.

Background: Expanding urbanization and increasing the number of vehicles have led to adverse effects on both the environment and human health. The propose of this study is to evaluate the concentration of CO2, CO, HC, O2, NOX in the exhaust outlet of vehicles tested in technical examination center, and to determine the relationships between their variation and lambda coefficient, type of fuel injection system as well as vehicle type. Methods: This cross-sectional study was conducted on 1000 vehicles tested in technical examination centers in Hamadan city. To do this, the concentrations of CO2, CO, HC, O2, NOX gases emission were obtained, and then the relations between variation of these gases and lambda coefficient, type of fuel injection system and vehicle type were investigated. The statistical analysis that used in this study include one-way ANOVA and independent t-test (SPSS 16). Results: The results of this study showed a significant relationship between the concentration of emitted gases and the lambda coefficient, the vehicle type and the type of fuel injection system (p

Background and purpose: Today, due to improvement and progress of human knowledge in food industry, plastic coatings such as PET (polyethylene terephthalate) that has unique characteristics are widely used for food and beverage packaging such as water and doogh. Phthalate esters are used in order to improve flexibility, efficiency and sustainability of materials. Chronic exposure with such materials play a role in incidence of many diseases and cancer in human. The aim of this study was to investigate the presence and concentration of phthalates in different brands of doogh. Materials and methods: In this study, we synthesized multi-walled magnetic carbon nanotubes using iron oxide. Then, the synthesized magnetic nanotubes were used for absorption and extraction of phthalate esters from doogh matrix. After sample preparation, the concentration of each phthalate esters was measured by GC-MS. Results: Concentration of phthalate esters in all samples were found to be lower than the standard levels but DEHP had the highest concentration. Statistical analysis showed no significant differences between the concentration of phthalate esters in different brands and storage time of doogh. Conclusion: According to these findings and low concentration of each phthalate ester compared with standard levels in different types of doogh, it has no health effect on consumers.

Background: 2،4 dichlorophenol (DCP), one of the most chlorophenol compounds family with highly toxic effect, exists in agricultural areas, chlorinated waters, discharging wastewater of pulp industries and paper factories. Chlorophenols can cause damages to the kidneys, liver, pancreas and weaken the central nervous system (CNS). In the current study we would evaluate the adsorption of DCP by chitosan in aqueous environments. Materials and Methods: In this study we evaluated the effect of operational parameters such as time (15-90min), pH values (3-9), initial concentration of DCP(15-100mg/l)and the dose of chitosan (0.1-0.9g) in a batch reactor. A spectrophotometer at wavelength of 280nm was used to measure the concentration of DCP. Freundlich and Langmuir isotherm models and Pseudo-first order kinetic models and Pseudo-second-order kinetic was drawn by using of the results obtained in the absorption process. Results: Equilibrium time in the adsorbtion process was estimated to be 75 minutes (DCP Concentration- 15mg/l, Chitosan Concentration – 0.5g and pH- 6.5) with 76% removal efficiency. PH=3 was calculated as the optimal PH in absorption process (DCP Concentration- 15mg/l, Chitosan Concentration- 0.5g and Time Equilibrium-75 min) with efficiency 79% and the value of efficiency decreased by increasing PH. In 15 mg/l concentration of DCP maximum adsorption with an efficiency of 79% was observed. (Chitosan Concentration – 0.5g, Time Equilibrium -75 min and pH-3) and the maximum 87% adsorption efficiency of DCP was observed at the 0.08mg/l absorbent dose of chitosan. (DCP Concentration - 15mg/l, time equilibrium-75 min and pH=3). Adsorption process follows of Freundlich isotherm with correlation coefficient of 0.9599 and the pseudo second order kinetic model with correlation coefficient of 0.9649. Conclusion: According to results of the study, chitosan can be used to remove of DCP from industrial wastewater due to of its perfect characteristics such as biodegradability, resurgent ability, low cost and adsorption acceptable efficiency.

Objective: The present study was conducted to find out how to manage the crisis in holding sporting events during the Corona pandemic.Methodology: This research is based on Murphy's three-stage model. In Murphy's model, crisis management is examined in three stages: pre-crisis, syn-crisis and post-crisis. Based on this model, the basic interview questions were compiled and the qualitative data obtained from the interviews were analyzed, and finally, the qualitative data of crisis management in holding sporting events during the Corona were investigated. This framework was designed according to the crisis life cycle and for each of the pre-crisis, syn-crisis and post-crisis stages, the goals, strategies and measures necessary to face the crisis in holding sporting events during the Corona are presented.Results: According to the findings of pre-crisis research, the main goal is prevention, which is achieved through preparedness and empowerment strategies. In the second stage, the main goal of impact management is pursued through two strategies: action / reaction and harm reduction. Finally, in the post-crisis phase, the strategies were marketing recovery, financial management / operational efficiency, and business resilience.Conclusion: The results show that managers and organizers of sporting events must adopt the necessary strategies and measures in order to achieve the goals set for each of the pre-crisis, syn-crisis and post-crisis stages.The results of the present study include measures such as pre-crisis forecasting, learning, participation and adaptation to the new post-crisis system, which are important and necessary in crisis management.Therefore, in the pre-crisis stage, the following measures were identified: designing and creating a crisis management system in sports events, planning to prepare sports businesses in the face of possible crises, creating a dynamic system for predicting possible events and crises in sports events and related businesses, creating integration and coordination between internal and external elements of sporting events and related businesses, establishing a comprehensive information management system for forecasting, planning and managing the effects of sporting events, training manpower and managing sporting events and related businesses as the key to success in crisis management. Capacity building to empower actors at sporting events and related businesses, and defining financing mechanisms for businesses to empower them in the face of potential crises are suggested.