87 research outputs found

    Investigation of Qualitative Condition of Nekarud River and Tajan River by NSFWQI Index

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    Rivers are exposed to large amounts of impurities. The first step for keeping river water quality and purification of polluted parts is obtaining information on the qualitative changes of river water in dimensions of time and place and also, determination of major sources and various water pollutants. Analysis of measured parameters alone or in combination, give in complete information on water quality because of variety of parameters, samples and stations. WQI is a mathematical and statistical tool for conversion of quantitative values of large quantity of water quality data into single number which presents a simple and understandable tool for qualitative assessment. Samples were collected seasonally from stations at upstream, middle stream and downstream of two rivers in east of Mazandaran province (Nekarud River, Tajan River) in a 2 years interval of 2011-2012 years, and analyzed in laboratory of  Environmental Protection agency of Mazandaran according to standard methods. The values of NSFWQI (water quality index ofAmerica’s national health organization) were calculated for all stations and all of the stations were located on the level of unsuitable conditions. The condition of Tajan River was relatively better than Nekarud River due to lower residential villages and towns around the river

    Investigation of Qualitative Condition of Nekarud River and Tajan River by NSFWQI Index

    Get PDF
    Rivers are exposed to large amounts of impurities. The first step for keeping river water quality and purification of polluted parts is obtaining information on the qualitative changes of river water in dimensions of time and place and also, determination of major sources and various water pollutants. Analysis of measured parameters alone or in combination, give in complete information on water quality because of variety of parameters, samples and stations. WQI is a mathematical and statistical tool for conversion of quantitative values of large quantity of water quality data into single number which presents a simple and understandable tool for qualitative assessment. Samples were collected seasonally from stations at upstream, middle stream and downstream of two rivers in east of Mazandaran province (Nekarud River, Tajan River) in a 2 years interval of 2011-2012 years, and analyzed in laboratory of  Environmental Protection agency of Mazandaran according to standard methods. The values of NSFWQI (water quality index ofAmerica’s national health organization) were calculated for all stations and all of the stations were located on the level of unsuitable conditions. The condition of Tajan River was relatively better than Nekarud River due to lower residential villages and towns around the river

    The Development of an Empirical Model for Estimation of the Sensitivity to Heat Stress in the Outdoor Workers at Risk

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    Background: Workers who work in hot environments may be at risk for heat stress. Exposure to heat can result in occupational illnesses, including heat stroke, heat cramps, and heat exhaustion. The risk of exposure to heat depends on individual, environmental, and occupational risk factors. Individual risk factors may decrease the individual’s tolerance to heat stress. Sensitivity as an intrinsic factor may predispose a person to heat stress. Aim: This study was aimed to determine the criteria for sensitivity parameter, specify their weights using the fuzzy Delphi-analytical hierarchy, and finally providing a model to estimate sensitivity. The significant of the study is presenting a model to estimate the sensitivity to heat stress. Materials and Methods: The expert’s opinions were used to extract the criteria in Delphi method. After determining the weight of each criterion, Fuzzy analytic hierarchy Process (FAHP), by mathematical principles matrix and triangular fuzzy numbers, was applied for the prioritization of criteria. Results: According to experts’ viewpoints and considering some exclusion, 10 of 36 criteria were selected. Among 10 selected criteria, age had the highest percentage of responses (90% (27/30)) and its relative weight was 0.063. After age, the highest percentages of response were assigned to the factors of preexisting disease (66.6% (20/30)), body mass index (56.6% (17/30)), work experience (53.3% (16/30)), and clothing (40% (16/30)), respectively. Other effective criteria on sensitivity were metabolic rate, daily water consumption, smoking habits, drugs that interfere with the thermoregulatory processes, and exposure to other harmful agents. Conclusions: Eventually, based on the criteria, a model for estimation of the workers’ sensitivity to heat stress was presented for the first time, by which the sensitivity is estimated in percent.Keywords: Heat stress, Sensitivity, Personal factors, Fuzzy AH

    Elimination of carbon monoxide using non-thermal plasma

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    Background and aims: Non-thermal plasma is considered as a successful new technology with high efficiency in the air pollution control. Various types of atmospheric pollutants adversely influence on the human health and the environment regionally and globally. Carbon monoxide has been introduced as a critical pollutant which can cause the environmental and health effects. The growing concerns about effects of air pollution on human health, and also more stringent strategies of choosing the air quality standards, have motivated the development of air pollution control techniques, particularly the non-thermal plasmas techniques. Therefore, the aim of this study is the removal of the carbon monoxide (CO) contaminants in the dry air and argon atmospheres in order to determine of the effective parameters. Methods: The current study has determined the effects of temperature, the CO concentration, the voltage and the residence time on the CO elimination efficiency by ASTM D 5835 method in the system of negative plasma reactor (diluted by dry air) and the system of positive plasma reactor (diluted by argon gas), simultaneously. Results: The results indicated that the temperature and the residence time did not have a significant effect on the CO removal in the both dry air and argon gas systems. However, the most important variable in the both systems was the voltage in the vicinity of 8 kilovolts with the p<0.05 and the mean effect of 37 and 13.2 in the dry air and argon gas systems, respectively. Conclusion: The results of CO elimination in the dry air and argon atmosphere indicate that the dry air system, due to present of the oxygen active ions, has better performance compared to the argon gas system

    Design and evaluation of the performance of local exhaust hood on the welding torch

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    Background and aims: Threats against welders' health due to exposure to welding fume is an important issue; thus, controlling and examining effective exhaust of fumes are necesary. In this study, was evaluated prototype operation of local exhaust ventilation on-gun in bench scale. Methods: Duct velocity average was determined using traverse points method and calculated flow rate by hood using ACGIH standard method. Also capture velocity close in contaminant source (Arc Point) was measured using thermal anemometer. Then, in order to determine total particles concentration and capture efficiency created by system NIOSH 7200 standard method was used. Results: Duct velocity average and created flow rate by evaluated system were 6296.1±92.50 fpm and 34.06±0/50 scfm, respectively. Also, capture velocity in close of the weld point was obtained 140 fpm. Sampling results for averaged total particles concentration in off and on positions of system were 75±7 mg/m3 and 16.7±4 mg/m3, respectively. As a result, 77 containment efficiency was achieved by this system. Conclusion: The local exhaust ventilation used in this study was a low cost prototype and according to the acheived results, it leads to reduce total particles concentration (T.P) in breathing zone aproximately to 22

    Fabrication and optimization of electrospun polyacrylonitrile nanofiber for application in air filtration

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    Background and aims: In nanofibrous filters, morphological properties, diameter of fibers and porosity percent of media are the most filtration characteristics. Therefore, the present study aimed to optimize the electrospinning parameters for reaching to the desired values of the mentioned filter characteristics. Methods: For this purpose, a study design was prepared using response surface methodology (RSM), in which electrospinning factors such as solution concentration, applied voltage and electrospinning distance were considered input variables and the fiber diameter, porosity, bead number and average bead diameter to average fiber diameter (ABD/AFD) ratio were considered the output variables. Morphological features of fibers and porosity of media were done through image processing approach of Scanning Emission Microscopy (SEM) images. Results: Maximum concentration in assessed range can provide the best morphology and also the maximum diameter. The highest correlation coefficient has been seen between fiber diameter and solution concentration (p 0.05, r=0.39). There was the significant relationship between both concentration and electrospinning distance and bead size (r=-1.6, r=0.56, respectively). Bead number was decreased specially with increase in concentration. Conclusion: Totally, RSM could well determine the relationship between input and response variables. High regression coefficient in mathematical models indicated the importance of the experimental values. The validation test shown the experimental data are in good agreement with the predicted ones

    Efficacy of sexual counseling based on PLISSIT model on sexual functioning in women with polycystic ovarian syndrome

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    Background and purpose: Women with Polycystic Ovarian Syndrome (PCOS) suffer from sexual dysfunction that is largely ignored in health clinics. This study was conducted to assess the efficacy of Permission, Limited Information, Specific Suggestion, Intensive Therapy (PLISSIT) model on sexual function of women with PCOS.. Materials and methods: This randomized clinical trial was performed in 66 women with PCOS aged 18-45 years old. They were divided into intervention and control groups (n=33 per group). Four weekly sessions of one hour individual counseling based on PLISSIT model were performed for the intervention group, while the control group received only routine care. Female Sexual Functioning Index questionnaire was completed at pre-test, and one month and three months after that in both groups. Data analysis was done applying Friedman, Mann-Whitney U, and Wilcoxon tests. Results: There were homogeneity in subjects� mean age (29.26±5.96), educational level (12.02±2.65) and BMI (25.95±3.67). Also, the two groups were similar in terms of symptoms including hirsutism, acne, alopecia, infertility and menstrual status. The mean scores for sexual functioning were 20.39±2.56, 24.40±4.70 and 23.73±1.26 at pre-test, after the intervention, and follow-up in intervention group, respectively (P<0.001), but no significant differences were seen between the scores of the control group (P=0.405).Also, the scores for lubrication were not significantly different between the two groups at post-intervention (P=0.245) and follow-up (P=0.423). Conclusion: The PLISSIT model improved sexual functioning in women with PCOS, therefore, it could be recommended as an assessment and management tool in investigating sexual problems at early stages in this group of women. © 2019, Mazandaran University of Medical Sciences. All rights reserved

    Differences in and correlates of sexual function in infertile women with and without polycystic ovary syndrome

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    Background: The aim of this study was to examine sexual function and its correlates among infertile women with polycystic ovary syndrome (PCOS) in comparison with their non-PCOS counterparts. Materials and Methods: In this case-control study, 209 infertile women (116 PCOS and 93 non-PCOS) from Tehran, Iran, were evaluated in February and March 2018. Female sexual function index (FSFI), hormonal status, and documented reports of hyperandrogenic manifestations of the patients were investigated. Results: The mean age of the patients was 32.00 ± 5.00 years old. Eighty-four (40.2) patients including 42.2 of the PCOS patients and 37.6 of the non-PCOS cases (P>0.05), were suspected of female sexual dysfunction (FSD). The most impaired functions in both groups were desire and arousal. Sexual function was not significantly different between the groups. However, PCOS women had more orgasm problems and acne worsened their sexual function. Total FSFI was positively associated with prolactin level but negatively associated with central obesity in the non-PCOS group; it was negatively correlated with marital duration in the PCOS group. Luteinizing hormone (LH) and pain, prolactin level and lubrication, and central obesity and arousal were correlated in the non-PCOS women. Prolactin level and orgasm, marital duration and arousal, and marital duration and the total FSFI were correlated in the PCOS women. Conclusion: Sexual function was similarly low in infertile PCOS and non-PCOS women. However, orgasm problems and the negative effect of acne varied between the two groups. Further investigations may target how hormonal profile may affect sexual function. Practitioners should scrutinize the specific impaired sexual domains and their correlated conditions in PCOS women, notably orgasm, acne, and prolactin level. Interventions should be well tailored based on particular needs of infertile PCOS women. © 2021, Royan Institute (ACECR). All rights reserved

    Exposure to heat stress in the workplace: A systematic review

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    Background and aims: Working in hot environments is one of the common physical risks factor in the workplace, which can also cause heat-related illnesses and various health effects on workers, and also increasing the risk of injuries and occupational accidents. The purpose of this paper is review conducted studies about heat stress in different countries, investigation the indices of heat stress, the characteristics of the exposure in hot environments, high-risk occupations, and sutvey the status and importance of these studies. Methods: In this review study used Web of Science, Scopus, Pubmed, ScienceDirect, Iran Medex, Magiran, Google Scholar and SID databases. The keywordsincluded Heat stress, Heat strain, Heat exposure, Heat waves, Workplace, Knowledge and attitude of workers about heat stress, the period of 2000 to 2015 was investigated, and finally 103 original articles were identifed. Results: 90 of all study being cross-sectional studies, 41 being related to outdoor workplaces, and 42 being related to indoor environment. 19 studies were about perceptions and behavioural responses of exposure to heat stress.A range of heat indices were used with 60 (71) studies using Wet Bulb Globe Temperature Index (WBGT). Most of studied focused on manufacturing workers and farmers. Most of studies indicated that workers were suffering from heat stress and strain. Conclusion: The results of reviewed studies showed that stress in workplace is worrying due to the nature of the working processes both indoor and outdoor, and of climate change. Therefore it is necessary to considering preventive and control programs to reduce the heat stress by the management and staff's participation to eliminate or reduce its lethal effects. © 2018 JTehran University of Medical Sciences and Health Services. All rights reserved
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