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Showing 8 results for Rezaei

Tahereh Mousavi, Farideh Golbabaei, Mohammad Reza Pourmand, Sasan Rezaei, Mostafa Hosseini, Mehrdad Helmi Kohneshahri, Ensieh Masoorian, Ali Karimi,
Volume 7, Issue 2 (6-2017)
Abstract

Introduction: Nowadays, HEPA filters is used in hospitals, clean rooms, microbiology hoods, ventilation of surgery rooms, and Pharmacy for removing microorganisms and reduce health hazard. The aim of this study is to increase the efficiency of HEPA filters with UVC radiation to reduce the density of airborne microorganisms.

Material and Method:  The closed–loop chamber was made to evaluate Staphylococcus epidermidis, Bacillus subtilis bacteria and Aspergillus Niger, Penicillium fungi. The concentration of fungi and bacteria suspension Respectively was 106, 107 CFU/ml. After the suspension was prepared, it was sprayed into the closed loop chamber by nebulizer. Sampling was done with UVC radiation (1.8 mW/cm2 Illuminance) and no radiation (dark) that included time periods 60, 90 and 120 minutes. Microorganisms density was determined in term of CFU/m3.

Result: The result showed that there was a significant difference between UVC radiation and dark section for all the microorganisms (epidermidis, subtilis, Niger and Penicillium) at each time periods (P value< 0.05). This indicates that concentration of four microorganisms were decreased at all the time periods. UVC radiation could change the essential molecular substances for cellular factor. UVC can penetrate the cell walls of microorganisms. thus nucleic acids and other cellular vital material affected and will cause the destruction or inactivation of microorganisms.

Conclusion: UVC radiation is effectiveness to decrease concentration of four microorganisms. because UVC radiation could remove both bacteria and fungi. While the other studies in other countries, UVA radiation is only effective in reducing bacteria. Therefore, achieved greater efficiencies of HEPA filters, using HEPA filters with UVC will have a significant effect on reducing the density of microorganisms.


Morad Rezaei Dizgah, Fardin Mehrabian, Mohsen Jani Pour,
Volume 8, Issue 1 (4-2018)
Abstract

Introduction: Job Satisfaction is a perception that improves employees’ productivity, motivation and empowers them. Therefore, recognizing the factors affecting it and paying attention to emotional intelligence can provide the basis for increasing job satisfaction.
The purpose of this study was to investigate the effect of emotional intelligence on job satisfaction considering the mediator role of job burnout, emotional Labor, emotional inconsistency, personality deprivation and deficiency of individual success in the Staff of Guilan University of Medical Sciences
 

Material and Method: This research used descriptive and cross-sectional method. The study population included 413 staffs from the faculties of Guilan University of Medical Sciences. The sample was determined 200 people using Cochran’s formula. A standard questionnaire was used to collect data. Content validity was done for this  questionnaire  and also its reliability studied using Cronbach’s alpha coefficient. Descriptive statistics and structural equation modeling were used to analyze the data using Lisrel software.
 

Result: The results showed that emotional intelligence affects emotional inconsistency, emotional exhaustion, emotional Labor, job satisfaction, deficiency of individual success and deprivation of personality. Also, emotional inconsistency affects on emotional exhaustion, deficiency of individual success, job satisfaction and personality deprivation. In addition, the results show that emotional exhaustion affects deprivation of personality, deficiency of individual success and job satisfaction and finally, the deficiency of individual success affects job satisfaction.
 

Conclusion: Considering the relationship between job satisfaction with job burnout, emotional intelligence and emotional inconsistency, it would be helpful for managers to implement programs to increase employee satisfaction and self-efficacy and provide a context for reducing job burnout.


Roohollah Ghasemi, Farideh Golbabaei, Mohammad Javad Jafari, Mohammad Reza Pourmand, Sasan Rezaei, Ramin Nabizadeh, Ensieh Masoorian,
Volume 9, Issue 2 (6-2019)
Abstract

Introduction: Air pollution is now recognized as an important environmental and health concern. Biological control processes, due to their durable, cost-effective and eco-friendly, have become a good alternative to physic-chemical methods. Biotechnology is based on the activity of microorganisms.
The aim of this study was to compare the capability of Pseudomonas Putida PTCC 1694 (bacteria) and Polarotus Stratus IRAN 1781C (mushroom) in the removal of toluene from the air stream and its biodegradation under same operating conditions.
Material and Methods: To this purpose, a bio filter containing two parallel columns was designed and constructed on a laboratory scale and the experiments were carried out based on measuring the removal efficiency (RE), elimination capacity (EC) and pressure drop in these two columns. Thus, the bacteria were inoculated in one of the columns and in the other the fungus was inoculated.
Results: The bacterial testing lasted for 20 days and the fungal testing lasted for 16 days. The contaminant loading rates (LR) for bacterial and fungal bio filters were 11.65±2.26 and 11.94±2.56 g/m3.h, respectively. The results showed that the fungal bio filter was more capable of eliminating of toluene vapor than bacterial bio filter (9.65±3.53 vs 9.18±2.6 g/m3.h). However, the pressure drop in the bacterial bio filter was lower than the fungal bio filter (1±0.28 vs 1.1±0.32 cm water).
Conclusion: According to the results, fungal bio filtration appeared to be more successful than bacterial bio filtration in the removal of toluene.
Sara Karimi Zeverdegani, Masoud Rismanchian, Samira Barakat, Mehdi Mirrezaei, Akbar Hassanzadeh,
Volume 10, Issue 3 (8-2020)
Abstract

Introduction: The most common of farmers' occupational exposure is exposure to pesticides. Organophosphate pesticides (OP) are widely used in agriculture to control pests. The main mechanism of Organophosphates (OPs) toxicity is irreversibly inhibiting of Butyl cholinesterase and acetyl cholinesterase. POEM model (Predictive Operator Exposure Model) was made to assess exposure and absorption of the pesticides. The aim of this study was to estimate the rate of exposure of farmers in West of Iran to organophosphates with POEM model and to compare its results with activity level of plasma cholinesterase (PChE).
Methods and Materials: In this descriptive and analytical research, farmers were divided into two same groups who were exposed to diazinon. One group of them wore full personal protective equipment (PPEs) and the second group including farmers with daily routine work had no proposed personal protective equipment. Before and after spraying operation, a blood sample was collected from both groups of farmers, as well as from control group. Then plasma cholinesterase activity was measured by DGKC (German Biochemical Society) and photometric device. Farmer’s exposure to OPs was estimated with POEM model.
Results: The activity mean PChE enzyme in the groups with and without personal protective equipment was 11639.3 mg/l and 8516.3 mg/l, respectively. The mean of predicted total absorbed dose and predicted total exposure to toxic substance in group with PPEs was 9.1 mg/day and 0.15 mg/kgbw/day, respectively and in group with PPEs were 0.5 mg/day and 0.009 mg/kgbw/day, respectively. dermal exposure average, percentage of dermal absorption, absorbed dose at the time of preparing the poison solution and spraying, by using of the POEM model was significantly higher in the no PPE group than in the PPE group (P<0.001).
Conclusion: This study showed that the use of personal protective equipment prevents from the effects appearing of pesticides by reducing the activity of PChE. With the increasing in PChE activity, the values of POEM model parameters decreases such as the absorbed dose of the skin and the inhalation of the toxin. Therefore, the POEM model can be used to check the exposure of people with pesticides. Finally, this study suggests that from the POEM model can be considered as a screening tool to identify individuals at exposure of pesticides to the next steps for biological monitoring, diagnosis and treatment and … .
Meghdad Kazemi, Vida Rezaei Hachesu, Rajabali Hokmabadi, Seyed Jamaleddin Shahtaheri,
Volume 11, Issue 1 (3-2021)
Abstract

Introduction: Perpetration of samples is one of the most important stages needed for trace residue analysis of biological specimens when human exposure assessment is required. The samples preparation process makes the analyte get more purified and enriched as well as more compatible to the analysis instrument systems. The present study has concentrated on a systematic review of different articles published regarding the sample preparation methodologies of human biological samples.
Material and Methods: In this systematic review, all articles related to the development of sample preparation for trace residue analysis of heavy metals in occupational biological samples published in English during 2009-2019, were considered. To meet the desired objective of the current study and facilitate the  related articles on physiochemical sample preparation methods accessibility combined keywords of Mesh and non-Mesh, without any limitation in the type of studies, the Pubmed, Web of Science, and Scopus were considered to be searched. Noteworthy, in this study, only the articles related to the workers’ biological samples were reviewed.
Results: Based on the obtained results, after reviewing of the keywords trough websites, 2964 articles were identified. Then, the redundant papers were removed and59 articles were remained, based on their titles and abstracts,. After detailed review of selected articles, regarding the study criteria, 8 articles were selected for the final systematic review.  Five articles out of 8, (62.5%) were allocated to the development of sample preparation for mercury in biological samples. It is worth mentioning that the majority of biological samples were regarded to the urine samples (75%) in the current study. Based on the obtained results, Solid Phase Extraction (SPE), applied in 37.5% of studies, was a popular method used in sample preparation.
Conclusion: The development of sample preparation approaches indicates a great promise for specified methods with low costs and less extraction time when separating different heavy metals from complex matrices. These sample preparation and preconcentration techniques ease the analyses processes and provide the quantitative recoveries, higher sensitivity, and lower detection limits.
Vida Rezaei- Hachesu, Shadi Naderyan Fe’li, Khadije Maajani, Rajabali Hokmabadi, Farideh Golbabaei,
Volume 12, Issue 1 (3-2022)
Abstract

Introduction: Covid-19 pandemic has imposed a significant effect on mental health of the health care workers. The present systematic review and meta-analysis aimed at determining the pooled prevalence of anxiety and depression among Iranian health care workers during the Covid-19 pandemic.
Material and Methods: To conduct this systematic review and meta-analysis, Web of Science, Scopus, Medline (PubMed), Embase, SID, Magiran databases and Google Scholar search engine were investigated to find studies over the prevalence of anxiety and depression among health care workers during the Covid-19 pandemic from December 2019 to June 10, 2021. Quality of the primary studies was assessed using the Newcastle-Ottawa tool and the random effects model was applied to estimate the pooled prevalence. Furthermore, χ2 test and I2 index were used to evaluate the degree of heterogeneity among the studies. The pooled prevalence of anxiety and depression in different subgroups was reported based on the severity of anxiety and depression, assessment tools, and staff jobs.
Results: Of 488 articles obtained as a result of the initial search, 10 related studies were identified and entered into the systematic review and meta-analysis. The pooled prevalence of anxiety was 42% (95% CI: 25-75) and the pooled prevalence of depression was 35% (95% CI: 19-55). The pooled prevalence of anxiety was 54% (95% CI: 39-70) in the occupational group of nurses and 29% (95% CI: 17-44) among all health care workers. The pooled prevalence of depression was 46% (95% CI: 30 to 63) and 17% (95% CI: 10 to 26) among nurses and all health workers, respectively.
Conclusion: According to the findings, a high prevalence of anxiety and depression was observed among the health care workers of Iran during the Covid-19 epidemic. The authorities are required to plan for preventive and therapeutic interventions to reduce the psychological burden of the epidemic.
Rajabali Hokmabadi, Mohsen Mahdinia, Vida Rezaei Hachesu, Ali Karimi,
Volume 12, Issue 2 (6-2022)
Abstract

Introduction: Sleep is one of the important physiologic needs in daily life cycle, and a part of quality of life. Sleep disorders are considered as one of the most common health problems in work communities that can affect physical, mental performance and ability to work. Therefore, this study aimed at investigating the relationship between sleep disorders and work ability in construction workers.
Material and Methods: This study is descriptive-analytical and cross-sectional. Samples of 220 people were selected by random sampling method from construction workers and personnel. Data collection tools in this study included sleep quality questionnaire, insomnia severity questionnaire and work ability questionnaire. Data were analyzed using SPSS software (version 19) and, considering the objectives, descriptive statistics and analytical tests including paired t-test, Pearson’s correlation, Kruskal-Wallis, multiple linear regression and logistic regression were used.
Results: Average age, body mass index, working hours and work experience were calculated as 34.2 ± 8.5 years old, 55.58 ± 2.78, 10.5 ± 1.25 hours and 12.7 ± 6.5 years, respectively. The mean indices of insomnia severity, Petersburg quality of sleep index and work ability were 6.6 ± 5.35, 4.95 ± 2.43 and 42.5 ± 5.13, respectively. The relationship between the work ability with sleep disorders was statistically significant. Variables of marital status, types of employment and smoking, independent of the variables of insomnia severity and sleep quality, significantly affected the work ability index, so that the R2 of these variables were 0.246 and 0.242 of the changes in work ability index, respectively.
Conclusion: Any disturbance in sleep and resting can cause poor sleep quality. As a result, it severely reduces the ability of employees to work. Therefore, it is suggested that, in order to increase the index of work ability and, thus, the efficiency of an organization, special attention be paid to sleep-resting programs of employees.

Vida Rezaei-Hachesu, Hassan Haddadzade Niri, Saeid Farahani, Mohammad Reza Monazzam Esmaeelpour,
Volume 13, Issue 2 (6-2023)
Abstract

Introduction: Colored noises with acoustic and psychoacoustic characteristics have several biological effects on human or animal health. While studies on auditory effects focus on noise’s physical aspects, its psychoacoustic aspects can also result in health and safety risks. Therefore, this study aims to investigate frequency-based damages due to exposure to colored noise in an animal model.
Material and Methods: Twenty-four male Wistar rats were randomly divided into four groups (6 in each group). The groups included the control (no exposure) and three exposure groups (white, pink, and violet). The rats were exposed to 110 dB SPL for 4 hr/day for 14 consecutive days. Auditory brainstem responses (ABR) with click and tone-burst stimuli were recorded one day before (baseline), 7, and 14 days after exposure. Statistical analyses were conducted using ANOVA and repeated measures ANOVA.
Results: There was a statistically significant increase in ABR threshold values in exposure groups (p<0.05). Hearing threshold shifts in the white noise group showed a homogeneous pattern, violet noise showed an increasing pattern, and pink noise showed a decreasing pattern in low frequencies and a homogeneous pattern with increasing frequency. The highest shift in hearing threshold was observed in exposure groups from day 0 to 14. Additionally, the shift in hearing threshold in the second week was less than in the first one.
Conclusion: The current study observed that noise’s power spectral density affected hair cells’ damage severity. Accordingly, pink noise causes less damage to the cochlea compared to white and violet. Over time after noise exposure, cochlear pathogenesis gradually decreases and hair cell lesions become stable.

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