Thermodynamic modeling of pressure-temperature phase diagrams of binary clathrate hydrates of methane, carbon dioxyide or nitrogen+tetrahydrofuran,1,4-dioxane or acetone

International audienceIn this communication, we report a thermodynamic model for predicting pressure-temperature phase diagrams of binary clathrate hydrates of methane, carbon dioxide or nitrogen. +. tetrahydrofuran (THF), 1,4-dioxane or acetone for various concentrations of the latter water-soluble chemicals in aqueous solution. The model is based on equality of water fugacity in the aqueous and hydrate phases. The solid solution theory of van der Waals-Platteeuw is used for calculating the fugacity of water in the hydrate phase. The UNIFAC group contribution model is used to calculate the water and THF, 1,4-dioxane or acetone fugacities in the aqueous phase. The Peng-Robinson equation of state is employed to calculate the gas phase fugacity. It is assumed that the gas phase is pure. The results of this model are compared with some selected experimental data from the literature. Acceptable agreement between the model predictions and experimental data demonstrates its reliability

Assessing preventive health behaviors from COVID-19: a cross sectional study with health belief model in Golestan Province, Northern of Iran

Background: Coronavirus disease 2019 (COVID-19) is a new viral disease that has caused a pandemic in the world. Due to the lack of vaccines and definitive treatment, preventive behaviors are the only way to overcome the disease. Therefore, the present study aimed to determine the preventive behaviors from the disease based on constructs of the health belief model. Methods: In the present cross-sectional study during March 11�16, 2020, 750 individuals in Golestan Province of Iran were included in the study using the convenience sampling and they completed the questionnaires through cyberspace. Factor scores were calculated using the confirmatory factor analysis. The effects of different factors were separately investigated using the univariate analyses, including students sample t-test, ANOVA, and simple linear regression. Finally, the effective factors were examined by the multiple regression analysis at a significant level of 0.05 and through Mplus 7 and SPSS 16. Results: The participants� mean age was 33.9 ± 9.45 years; and 57.1 of them had associate and bachelor's degrees. Multiple regression indicated that the mean score of preventive behavior from COVID-19 was higher in females than males, and greater in urban dwellers than rural dwellers. Furthermore, one unit increase in the standard deviation of factor scores of self-efficacy and perceived benefits increased the scores of preventive behavior from COVID-19 by 0.22 and 0.17 units respectively. On the contrary, one unit increase in the standard deviation of factor score of perceived barriers and fatalistic beliefs decreased the scores of the preventive behavior from COVID-19 by 0.36 and 0.19 units respectively. Conclusions: Results of the present study indicated that female gender, perceived barriers, perceived self-efficacy, fatalistic beliefs, perceived interests, and living in city had the greatest preventive behaviors from COVID-19 respectively. Preventive interventions were necessary among males and villagers. © 2020, The Author(s)

Survey of breast self-exam and mammography compliance among female healthcare workers in Aq Qala City, Iran

Background: Breast cancer is the most common cancer among women. The objective of this study was to determine the breast self-examination (BSE) and mammography compliance based on health belief model constructs among female healthcare workers in the city of Aq Qala. Methods: We conducted this cross-sectional study between November 2015 and February 2016 in Aq Qala city, northern Iran. In this regard, we selected 261 female healthcare workers through census. Data were gathered using Rakowski�s stages of change and Champion health belief model scale. We entered the collected data into SPSS 16 and analyzed them via descriptive statistical techniques along with Kruskal-Wallis, Mann-Whitney, chi-square, and Spearman rank correlation coefficient. Results: The results showed that 26.4 of the participants performed regular BSE and 19.3 underwent regular mammogram. Those with regular BSE had significantly more health motivation and self-efficacy (P�0.05). Physicians had more susceptibility and self-efficacy for BSE and less BSE barriers (P�0.05). There was a negative correlation between BSE confidence and barriers (r=-0.376). The results of binary logistic regression revealed that confidence was the only variable influencing BSE (OR=1.77, 95 CI=1.22, 2.572). Conclusion: Almost one-fourth of female healthcare workers of Aq Qala performed regular BSE. Moreover, one-fifth of women over 40 years of age underwent regular mammograms. Participants who performed regular BSE had higher health motivation, BSE self-efficacy, and lower perceived barriers. BSE adherence was more in physicians than in other groups. We recommend increasing confidence to surmount the barriers to perform BSE. © 2020, Shiraz University of Medical Sciences. All rights reserved

Association of fear of COVID-19 and preventive behaviors (PB) against COVID-19 in Iran

Introduction: The world is currently experiencing a pandemic of COVID-19. The pandemic may affect physical and mental health. Therefore, this study aims to investigate the fear of COVID-19 and study the relationship between fear of COVID-19 and preventive behaviors against COVID-19. Material and methods: We conducted a web-based cross-sectional study to evaluate the fear of COVID-19 and preventive behaviors against COVID-19 among the volunteer population in Golestan Province, Iran in May 2020 and June 2020. The online questionnaire included the Fear of COVID-19 Scale (FCV-19S) and the prevention behaviors against COVID-19, which are used to assess the fear and prevention behaviors of the population, respectively. The data were presented by mean and frequency. Multiple linear regression analysis was performed to identify factors associated with Fear of COVID-19 at a significant level of 0.05 in Stata 14. Results: A total of 734 of the 900 individuals contacted completed the survey, with a participation rate of 81.5. The mean age of the participants was 33.97 ± 10.68 years and 375 (51.9) were females. The mean Fear of COVID-19 score in the participants was 19.69 ± 5.96. There was a significant positive correlation between Fear of COVID-19 and preventive behaviors (r = 0.19, p < 0.001). Multiple linear regression analysis showed participants with a higher perceived threat of COVID-19, women, married participants, health workers and people with underlying diseases had higher levels of fear of COVID-19. Conclusions: The fear of COVID-19 in Iranian society is high, which indicates the need to pay attention to the mental health in pandemic conditions. Appropriate intervention action can be designed and implemented according to the factors that affect fear. In addition, it should be noted that people with less fear are less likely to observe the COVID-19�s preventative behaviors. © Copyright 2021 Via Medic