Toward a Synergistic Optimization of Porous Electrode Formulation and Polysulfide Regulation in Lithium-Sulfur Batteries.

The use of functional materials is a popular strategy to mitigate the polysulfide-induced accelerated aging of lithium-sulfur (Li-S) batteries. However, deep insights into the role of electrode design and formulation are less elaborated in the available literature. Such information is not easy to unearth from the existing reports on account of the scattered nature of the data and the big dissimilarities among the reported materials, preparation protocols, and cycling conditions. In this study, model functional materials known for their affinity toward polysulfide species, are integrated into the porous sulfur electrodes at different quantities and with various spatial distributions. The electrodes are assembled in 240 lithium-sulfur cells and thoroughly analyzed for their short- and long-term electrochemical performance. Advanced data processing and visualization techniques enable the unraveling of the impact of porous electrodes' formulation and design on self-discharge, sulfur utilization, and capacity loss. The results highlight and quantify the sensitivity of the cell performance to the synergistic interactions of catalyst loading and its spatial positioning with respect to the sulfur particles and carbon-binder domain. The findings of this work pave the road for a holistic optimization of the advanced sulfur electrodes for durable Li-S batteries.

Application of Multiple Occupational Health Risk Assessment Models for Crystalline Silica Dust among Stone Carvers.

OBJECTIVE: Silica is the most abundant substance on the Earth's crust and is a proven carcinogen. The aim of this study was to measure the occupational exposure of stone carvers to crystalline silica and to evaluate the health risks.  Methods: This descriptive and analytical cross-sectional study was performed on 79 stone carvers. Inhalation air sampling was performed by the NIOSH7500 method and the amount of silica was determined by X-ray diffraction (XRD). Semi-quantitative and quantitative risk assessments were performed using the methods of the Singapore Department and the US Environmental Protection Agency (EPA), respectively. Mortality due to silicosis and lung cancer were estimated using the Manettej and Rice models. Data were analyzed using SPSS23 software. RESULTS: The mean exposure to total inhalable dust and crystalline silica among the stone carvers was 1.44 and 0.5 mg/m3, respectively. Exposure to total dust and silica was significantly higher than the occupational standard (P <0.0001). Stone carvers' exposure to silica was at very high-risk level, and the carcinogenicity of silica considering two cancer slopes was 7.40 × 10-6 and 3.12 × 10-7 and the risk of non-carcinogenicity was unacceptable. CONCLUSION: The mortality rate due to silicosis was between 3 and 12 people per thousand, and due to lung cancer was 150.24 people per thousand. Based on the results of risk assessment, serious control measures should be implemented in order to reduce workers' exposure to silica.

Determinants of sleep habits in toddlers: Application of planned behavior theory.

BACKGROUND: Sleep health is a prerequisite for mental and physical health. The family affects the sleeping habits of the child. OBJECTIVE: The purpose of this study was to investigate the theory of mothers' planned behavior in predicting sleeping habits of toddlers. METHODS: The participants of this descriptive-analytical study were 120 mothers of 12- to 36-month-old children living in Razan, Hamadan province, Iran. Data were collected in three stages in order to develop a theory-based tool. Semi-structured qualitative interviews with mothers were conducted to investigate the application of theory in predicting mothers' intention and behavior (n = 25). The face and content validity of the questionnaire was confirmed by a panel of experts. Test-retest method was used to determine the reliability of the questionnaire at 3 weeks interval (n = 25). Validity of Structural Convergence and Divergence with Factor Analysis, Internal Consent with Cronbach's Alpha and predictive validity was determined by multiple regression coefficients (n = 120). RESULTS: The mean age of the children was 22.8 ± 7.5 months, 55% (66 children) were boys, the mean score of the children's sleep questionnaire was 49 ± 6, and the children's sleep duration was 9 ± 1 hour. Theoretical constructs have a positive and direct correlation with each other and with children's sleep habits, which demonstrates the validity of the theory in predicting toddler sleep habits. Regression analysis showed that perceived behavioral control was the strongest predictor of sleeping habits of toddlers (𝛽 = 0.446) (P = 0.000). The theory of planned behavior can explain 30.5 to 25.7% of the variance of toddler sleep habits. CONCLUSION: While recommending more comprehensive studies, the findings of the study emphasize the application of the theory of planned behavior in identifying factors influencing sleep habits and designing child sleep improvement interventions.

Changes in Spirometry Indices and Lung Cancer Mortality Risk Estimation in Concrete Workers Exposed io Crystalline Silica.

The health of workers in the concrete and cement industries can be at risk due to occupational exposure to silica dust. The purpose of this study was to evaluate the changes of pulmonary parameters and risk of mortality from lung cancer in concrete workers exposed to crystalline silica. This cross-sectional study was performed on 72 male workers exposed to silica at a concrete manufacturing plant in Neyshabur, Iran. Respiratory zone air sampling was performed using the standard NIOSH7602 method using individual sampling pumps and membrane filters. Then, the amount of silica in the samples was determined using the Fourier Transform Infrared technique. The risk of death from lung cancer was determined using Rice et al.'s model. Respiratory indices were measured using a spirometer. Data were analyzed by the SPSS 20 software. Occupational exposure to silica was 0.025 mg/m3 and mortality was estimated to be 7-94 per thousand. All spirometry indices significantly decreased during these 4 years of exposure to silica dust. The respiratory pattern of 22% of the exposed workers was obstructive and this prevalence was significantly higher than the control group. The results showed that although the average occupational exposure to silica in these concrete workers was below the recommended threshold of national and international organizations, their risk of death was significantly higher; and workers' lung indices had significantly decreased over four years. Therefore, appropriate measures should be taken to reduce silica exposure among these workers.

Predicting Inpatient Length of Stay in Iranian Hospital: Conceptualization and Validation.

OBJECTIVE: The length of stay is an important indicator of hospital performance and efficiency. Regarding the importance of the length of stay, this study aimed to design a structural model of the inpatients' length of stay in the educational and therapeutic health care facilities of Iran in order to identify the influencing dimensions. METHODS: The present study was an analytical and applied study. The face validity of the data gathering tool was investigated by the expert judgment and the construct validity was examined by using the exploratory factor analysis. In order to verify the reliability of the tool, the internal consistency was also trialed by using the Cronbach's alpha. For ranking the influencing dimensions and factors and also in order to examine the causal relationships between the variables in a coherent manner and presenting the final model, the structural equation modeling technique was used in AMOS software at a significant level of 0.05. RESULTS: The mentioned structural model consists of 4 dimensions and 29 factors influencing the length of stay of hospitalized patients. The independent variables are based on priority and importance as follows: patients' conditions, the underlying factors, the clinical staff performance, and hospitals' service delivery, which were examined by second-order factor analysis in order to study the relationship between them and the inpatients' length of stay. CONCLUSION: Considering the importance of each one of the proposed dimensions from the point of view of service providers in some therapeutic centers of the country by paying attention to the role of each one of them in preventing prolonged hospitalization can be essential in the effectiveness of the treatment and cost reduction.
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Front-line staff's perspective on patient safety culture in Iranian medical centers: A systematic review and meta-analysis.

BACKGROUND: The prerequisite for promoting safety culture is to assess the existing safety culture level of institutes, because safety precautions without appropriate evaluation increase costs and unforeseen risks. OBJECTIVE: This study aimed to systematically review the status of patient safety culture from the perspective of clinical personnel at Iranian hospitals through a meta-analysis of studies using the Hospital Survey on Patient Safety Culture (HSOPSC) questionnaire. METHODS: The present systematic review and meta-analysis was conducted in 2018. Data were gathered by searching Google Scholar, Scopus, PubMed, and Web of Science databases up to November 2018. Search keywords were "patient", "safety", "culture", "healthcare", "hospital", "medical center", "HSOPSC tool", and "Iran". The search protocol was limited to 10 years. To estimate the PSC score, computer software CMA:2 (Comprehensive Meta-Analysis) was used. The presence of heterogeneity across the studies was assessed with the I2 statistic. A forest plot was used to report the results. Publication bias was assessed through a funnel plot. RESULTS: The meta-analysis of studies showed that the PSC score based on the random effect model was 52.7% (95% CI: 50.2%-55.2%), (Q = 522.3, df = 54, P < 0.05, I2 = 89.6). A mean of 12 dimensions of HSOPSC showed that the "Teamwork within units" dimension had the highest PSC score (67.2%) and "Non-punitive response to error" had the lowest score (40.4%). CONCLUSIONS: Managers and policymakers should be directed towards non-punitive responses to errors and persuade staff to report errors and execute the approach to learn from mistakes. Also, a periodic government evaluation of the patient safety culture will help further its sustainable development.

Effect of Occupational Exposure to Radar Radiation on Cancer Risk: A Systematic Review and Meta-Analysis.

OBJECTIVE: Microwave radiation is one of the most growing environmental workplace factors that exposes too many workers in the various workplaces. Regard to concerns about cancer incidence in these workers and lack of systematic or meta-analytic studies about this object, so, we conducted a meta-analysis to acquire an understanding of the association between cancer risk and occupational exposure to radar radiation. METHODS: A systematic search was carried out on case-control, cohort and clinical control trial studies that published in the Cochrane Library, PubMed, ISI Web of Science, Scopus and Google scholar databases that accomplished from March 2017 to March 2018 and updated on 30 September, 2018 in English and Persian articles without time limit in publication date. Keywords were selected based on PICO principle and collected from MeSH database. After removal of duplicated studied, taking into inclusion and exclusion criteria, the process of screening was carried out and data were extracted after preparation of the full text of included articles. Article collection was completed by manually searching for a reference list of eligible studies. For quality assessment of included studies, Newcastle-Ottawa scale was used. RESULTS: a total of 533 studies was found in the first step of literature search, only 6 were included with 53,008 sample size according to inclusion and exclusion criteria. Estimated pooled random effects size analysis showed no significant increasing effect of occupational exposure to radar radiation on mortality rate (MR=0.81, 95%CI: 0.78, 0.83) and relative risk (RR=0.87, 95%CI: 0.75, 0.99, P <0.0001) of cancer with a significant heterogeneity between the selected studies. CONCLUSIONS: In conclusion, the results of this meta-analysis study have shown no significant increase in overall mortality ratio and cancer risk ratio from occupational exposure to the radar frequency of workers. But, these results are not conclusive. As regards to some limitation such as fewer numbers of included studies, lack of data about exposure characterizations and demographic characterizations in this meta-analysis, this result is not certain and conclusive. It is recommended to conduct future studies.

Interaction of Safety Climate and Safety Culture: A Model for Cancer Treatment Centers

Background: In health care institutions, safety culture is defined as the integrity of individual and group efforts to reduce the harms for the patients. This is possible through interactions, attitudes, and understanding of safety matters. On the other hand, one of the indicators of the safety culture is the safety climate. Objective: The aim of this study is to investigate the interaction between safety climate and safety culture using structural equation modeling in personnel of cancer treatment centers in Iran. Methods: In this study, 680 personnel of Iran's hospitals were chosen in a random manner. Demographic (9 questions), safety culture (42 questions) and safety climate (37 questions) questionnaires were filled. The data were inserted in SPSS 20 software. Descriptive statistics method and Pearson's correlation coefficient were used to describe the data and evaluate the relation between the variables, respectively. Structural equations model was developed using AMOS 22 software and fitness of the model was tested by χ2, RMSEA, GFI and NFI statistics. Results: The scores of safety climate and safety culture were 3.61 and 3.30, respectively, which imply that they are suiTable. The overall fitness of the model was accepTable. In this model, χ2 = 8637.17, df = 2964, χ2/df = 2.914, RMSEA = 0.058, NFI = 0.912, GFI=0.907, and CFI=0.875. In the regression analysis, there were positive significant relationships between safety climate and safety culture, safety climate and any of its components, and safety culture and any of the components. Conclusion: It was found that the safety climate and the safety culture had a positive impact on each other; so that with increasing safety climate, the safety culture also increases, and vice versa. Also, the level of education has a positive impact on safety culture and safety climate. So appropriate training can promote both variables in cancer treatment hospitals.

Developing a model for hospital inherent safety assessment: Conceptualization and validation.

BACKGROUND: Paying attention to the safety of hospitals, as the most crucial institute for providing medical and health services wherein a bundle of facilities, equipment, and human resource exist, is of significant importance. OBJECTIVE: The present research aims at developing a model for assessing hospitals' safety based on principles of inherent safety design. METHODS: Face validity (30 experts), content validity (20 experts), construct validity (268 examples), convergent validity, and divergent validity have been employed to validate the prepared questionnaire; and the items analysis, the Cronbach's alpha test, ICC test (to measure reliability of the test), composite reliability coefficient have been used to measure primary reliability. The relationship between variables and factors has been confirmed at 0.05 significance level by conducting confirmatory factor analysis (CFA) and structural equations modeling (SEM) technique with the use of Smart-PLS. RESULTS: R-square and load factors values, which were higher than 0.67 and 0.300 respectively, indicated the strong fit. Moderation (0.970), simplification (0.959), substitution (0.943), and minimization (0.5008) have had the most weights in determining the inherent safety of hospital respectively. CONCLUSIONS: Moderation, simplification, and substitution, among the other dimensions, have more weight on the inherent safety, while minimization has the less weight, which could be due do its definition as to minimize the risk.

Risk Assessment of Exposure to Silica Dust in Building Demolition Sites.

BACKGROUND: Building demolition can lead to emission of dust into the environment. Exposure to silica dust may be considered as an important hazard in these sites. The objectives of this research were to determine the amount of workers' exposure to crystalline silica dust and assess the relative risk of silicosis and the excess lifetime risk of mortality from lung cancer in demolition workers. METHODS: Four sites in the Tehran megacity region were selected. Silica dust was collected using the National Institute for Occupational Safety and Health method 7601 and determined spectrophotometrically. The Mannetje et al and Rice et al models were chosen to examine the rate of silicosis-related mortality and the excess lifetime risk of mortality from lung cancer, respectively. RESULTS: The amount of demolition workers' exposure was in the range of 0.085-0.185 mg/m(3). The range of relative risk of silicosis related mortality was increased from 1 in the workers with the lowest exposure level to 22.64/1,000 in the employees with high exposure level. The range of the excess lifetime risk of mortality from lung cancer was in the range of 32-60/1,000 exposed workers. CONCLUSION: Geometric and arithmetic mean of exposure was higher than threshold limit value for silica dust in all demolition sites. The risk of silicosis mortality for many demolition workers was higher than 1/1,000 (unacceptable level of risk). Estimating the lifetime lung cancer mortality showed a higher risk of mortality from lung cancer in building demolition workers.

Assessment of Semi-Quantitative Health Risks of Exposure to Harmful Chemical Agents in the Context of Carcinogenesis in the Latex Glove Manufacturing Industry.

Excessive exposure to chemicals in the workplace can cause poisoning and various diseases. Thus, for the protection of labor, it is necessary to examine the exposure of people to chemicals and risks from these materials. The purpose of this study is to evaluate semi-quantitative health risks of exposure to harmful chemical agents in the context of carcinogenesis in a latex glove manufacturing industry. In this cross-sectional study, semi-quantitative risk assessment methods provided by the Department of Occupational Health of Singapore were used and index of LD50, carcinogenesis (ACGIH and IARC) and corrosion capacity were applied to calculate the hazard rate and the biggest index was placed as the basis of risk. To calculate the exposure rate, two exposure index methods and the actual level of exposure were employed. After identifying risks, group H (high) and E (very high) classified as high-risk were considered. Of the total of 271 only 39 (15%) were at a high risk level and 3% were very high (E). These risks only was relevant to 7 materials with only sulfuric acid placed in group E and 6 other materials in group H, including nitric acid (48.3%), chromic acid (6.9%), hydrochloric acid (10.3%), ammonia (3.4%), potassium hydroxide (20.7%) and chlorine (10.3%). Overall, the average hazard rate level was estimated to be 4 and average exposure rate to be 3.5. Health risks identified in this study showed that the manufacturing industry for latex gloves has a high level of risk because of carcinogens, acids and strong alkalisand dangerous drugs. Also according to the average level of risk impact, it is better that the safety design strategy for latex gloves production industry be placed on the agenda.