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Abstract Background During the COVID-19 pandemic, medical workers were concerned about the care of their children or family members and the impact of being separated from them. This increased stress could harm the relationship between nurses and patients. This study assessed how medical workers’ parental role may affect burnout during such a high-stress period. Methods This cross-sectional observational study was carried out in 2021 during the COVID-19 pandemic. The client burnout (CB) scale of the Copenhagen Burnout Inventory, the Nordic Musculoskeletal Questionnaire, and a demographic questionnaire were used. Statistical methods such as the t-test, one-way ANOVA, and univariable/multiple linear regression were applied. Results A total of 612 nurses were included in this study. The likely risk factors of CB were identified and the parenthood effect was found to be associated with reduced CB. The parental role and leisure activity with family and friends on CB were found to have an impact. Engaging in leisure activity with family and playing the role of a parent diligently will help relieve nurses’ burnout from frequent contact with patients and their families, thus lowering the risk of clinical burnout. Conclusion The parental role, family/friends relationships, and a complex work environment associated with nurses’ burnout during the COVID-19 pandemic. This finding allows us to re-examine the importance of family life and parent–child relationships in high-stress work environments.

Background: Problematic use of the internet (PUI) is prevalent, particularly among adolescents and young adults. Given the limited measures to assess specific types of PUI, which encompasses a broad spectrum of activities such as online gaming, social media use, pornography use, shopping, gambling, and web-streaming, Muller et al. (2022) developed the Assessment of Criteria for Specific Internet-use Disorders (ACSID-11) to comprehensively assess different types of PUI (i.e., gaming, shopping, social media use, gambling, and pornography use). The present study aimed to validate the Chinese ACSID-11 among adolescents incorporating cross-cultural adaptations. Methods: Using forward-backward translation method, a culturally adapted version of the ACSID-11 was prepared. Then, a cross-sectional online survey was administered between September 8 and September 26, 2023. Adolescents, using a convenience sample (N = 11,492; mean age = 16.42 years [SD ± 0.91]; 59.1% male), were recruited from six schools to complete the translated ACSID-11, Internet Gaming Disorder Scale-Short Form (IGDS9-SF), Bergen Social Media Addiction Scale (BSMAS), and Smartphone Application Based Addiction Scale (SABAS) via an online platform. Pearson correlation coefficients assessed convergent/discriminant validity. Factor structure and measurement invariance were examined through confirmatory factor analysis (CFA) and multi-group CFA. Cronbach's alpha and McDonald's omega tested internal consistency. Results: Associations between the ACSID-11 components and other scales supported convergent validity (i.e., ACSID-11 gaming scale with IGDS9-SF [0.37 ≤ r ≤ 0.41]; social networks use scale with BSMAS [0.24 ≤ r ≤ 0.31]) and discriminant validity (i.e., online gambling scale with BSMAS [0.16 ≤ r ≤ 0.19] and with SABAS [0.11 ≤ r ≤ 0.13]). A four-factor solution indicated good fit with comparative fit index (CFI) ranging from 0.982 to 0.958. The ACSID-11 was measurement invariant across sexes (∆CFI = -0.001 to 0.000) and different levels of related addictive behaviors (∆CFI = -0.001 to 0.000). Both Cronbach's alpha and McDonald's omega (0.63 to 0.97) were acceptable for both frequency and intensity of responses. Conclusions: The ACSID-11 is an appropriate scale to assess different kinds of PUI among Chinese adolescents and students. Psychometric assessment of the measure in other cultures and among clinical samples is recommended.

Understanding spatiotemporal correlations in power systems is crucial for maintaining grid stability, reliability, and efficiency. By discerning connections between spatial and temporal dimensions, operators can anticipate and address issues such as congestion, voltage instability, and equipment failures. Recent advancements in power system analysis have leveraged spatiotemporal correlations through sophisticated data-driven algorithms. In this survey paper, we conduct a comprehensive examination of deep learning frameworks tailored to tackle the complexities inherent in spatiotemporal data analysis within power systems. We categorize machine learning methodologies into discriminative, generative, and reinforcement learning, providing a structured overview of their mathematical foundations, advantages, and limitations in processing dynamic power system measurements. Through empirical evaluations, we assess the performance of these methodologies across various spatiotemporal applications, including cyber attack detection, fault identification, demand response, and renewable energy forecasting, offering insights into their efficacy and applicability. Additionally, we identify emerging topics within the machine learning domain that hold promise for future endeavors in power systems analysis.

Abstract Background Weight stigma is an issue often studied in Western countries; however, such information is scarce in Asian studies. Methods This study aimed to examine the role of internalized weight stigma as a mediator in the relationship between perceived weight stigma and changes in body mass index (BMI). The data were collected through a longitudinal online survey with two phases (n = 974; Phase 1: August and September 2021; Phase 2: November and December 2021). The Perceived Weight Stigma Scale (PWSS), Weight Self-Stigma Questionnaire (WSSQ), and Depression, Anxiety, Stress Scale − 21 (DASS-21) were administered to assess perceived weight stigma, internalized weight stigma, and psychological distress. Hierarchical regressions were used to examine the proposed model, and Hayes’ Process Macro was used to test a mediation model. Results The changes in perceived weight stigma and internalized weight stigma were significantly and positively associated with changes in BMI. There were significant and positive associations between perceived weight stigma, internalized weight stigma and psychological distress over time. Change in internalized weight stigma was found to be a significant mediator in the association of change in perceived weight stigma with change in BMI for the entire sample (unstandardized coefficient = 0.04; 95% CI = 0.02, 0.06), female subgroup (unstandardized coefficient = 0.05; 95% CI = 0.02, 0.08), and male subgroup (unstandardized coefficient = 0.03; 95% CI = 0.01, 0.06). Change in perceived weight stigma also had significant effects on change in BMI for the entire sample and the female subgroup, but not for the male subgroup. Conclusion Because perceived weight stigma may significantly impact changes in BMI through internalized weight stigma, treatment strategies to ameliorate self-stigma may enhance the results of weight-reduction programs. Such treatment strategies should be considered for inclusion in weight-loss interventions.

Non-equilibrium phenomena and related damages have always been one of the great concerns among researchers, designers, and industry managers. In power plants, the overhaul of turbines during a pre-planned schedule includes checking, repairing, and replacing damaged parts, which always challenge industry investors with variable costs. In this study, a modified profile for the stationary cascade blades of a 200 MW steam turbine is predicted by help of the Computational Fluid Dynamics (CFD) according to a cost-saving approach for a power plant. Wet steam model is used to investigate the flow behavior between the turbine blades, due to the sonication and non-equilibrium phenomena. The numerical model based on the Eulerian-Eulerian approach accounts the turbulence caused by the presence of droplets, condensation shocks and aerodynamics. At first, such model has been carefully validated against the available experimental data. Then, the entrance edge of the blade is designed considering different shapes and sizes. The flow behavior at the entrance edge region has been fully investigated. Finally, according to the criteria for measuring the non-equilibrium flow phenomena (erosion rate, Mach number, entropy, exergy destruction and transfer of mass and heat between flow phases), a modified model for the steam turbine blade considering the economic aspects has been presented. The modified blade model exhibits 88%, 0.13% and 7% reduction in the erosion rate, entropy generation and exergy destruction, respectively. Furthermore, the application of this modified blade profile save 456$ of the total monthly maintenance costs.

Abstract Background Depression is a mental health problem and substance use concerns are socially unacceptable behaviors. While depression and substance use may individually impact self-concept and social relationships, their co-occurrence can increase the risk of self-stigmatization. However, there is no evidence regarding how depression and self-stigma may influence each other over time. The aim of the current study was to evaluate the cross-sectional and longitudinal relationships between features of depression and self-stigma in people with substance use disorders. Methods Overall, 319 individuals with substance use disorders (273 males) with a mean (± SD) age of 42.2 (± 8.9) years were recruited from a psychiatric center in Taiwan by convenience sampling. They were assessed for features of depression and self-stigma at four times over a period of nine months using the depression subscale of the Depression Anxiety Stress Scales (DASS-21) and Self-Stigma Scale-Short S (SSS-S), respectively. Repeated-measures analyses of variance, Pearson correlations and cross-lagged models using structural equation modeling examined cross-sectional and temporal associations between depression and self-stigma. Results Positive cross-sectional associations were found between depressive features and all assessed forms of self-stigma over time (0.13 0.98). The direction of associations between depressive features towards self-stigma was stronger than the opposite direction. Conclusion Positive associations between depressive features and self-stigma were found in people with substance use disorders. Although these associations may be bidirectional longitudinally, the directions from depressive features to self-stigma may be stronger than the reverse directions, suggesting treatment of depression in earlier stages may prevent self-stigmatization and subsequent poor outcomes in people with substance use disorders.

Plain English summary Food addiction is related to eating disorders and may overlap with a variety of disorders, including binge-eating disorder, night-eating syndrome, bulimia nervosa or other conditions. Therefore, it is important for healthcare providers to assess food addiction and one commonly used method is using the Yale Food Addiction Scale (YFAS) developed by Gearhardt and her colleagues. The YFAS has been updated and revised into two versions: the YFAS 2.0 and modified YFAS 2.0 (i.e., mYFAS 2.0). Psychometric testing studies have reported the feasibility and adequate properties for both the YFAS 2.0 and mYFAS 2.0. However, prior studies’ findings were based on classical test theory (CTT) findings. The present study thus used a modern test theory (i.e., Rasch models) to examine if both the YFAS 2.0 and mYFAS 2.0 have similarly satisfactory psychometric properties shown in the CTT findings. The present findings using Rasch models support the use of both the YFAS 2.0 and mYFAS 2.0 to assess food addiction among youth. Therefore, healthcare providers may use either the YFAS 2.0 or mYFAS 2.0 to assess levels of food addiction.

Considering the growing trend of cancer incidence and mortality in the world, regardless of the human development level, cancer control and prevention programs should be a high priority in health policies. Developing the national cancer control program is in line with these efforts. Therefore, the current review study was conducted to examine the dimensions of national cancer control programs and the strategies used in these programs. This study was conducted to investigate the dimensions of the national cancer control program of different countries. To find relevant articles, the authors searched keywords, such as National Program of Cancer Registries, Screening, Neoplasms, Cancer, and Cancer Control separately and in combination in databases, including Google Scholar, Scopus, PubMed, and Science Direct. Furthermore, the Persian equivalents of these keywords were searched in Sid, Magiran, and Civilica. Finally, full text articles related to the cancer control program in Farsi or English published from 2000 to 2020 were selected. 586 articles were identified, and finally, 19 were investigated. The dimensions of the national cancer control program differed among countries and they had used different strategies to implement the cancer control program. The National Cancer Control Program is the most logical means to achieve a significant degree of cancer control, even in cases with limited resources.

Abstract In this paper, the thermal performance improvements of a heat removal system like an electronic system have been analyzed. The studied case is a horizontal channel in which two partially inclined baffles are attached with variable height and number. The channel is crossed by a forced convective flow of a cooling fluid (air). This numerical work evaluates the influences of the height and number of the baffles on the enhancement of the heat transfer rate. The mathematical model of this system is composed of nonlinear partial equations that the analytical solution for them is very complex, hence the need for numerical analysis is mandatory with the aid of a finite volume method. Accordingly, The numerical results are presented in axial and transverse velocity, temperature, local and average Nusselt number, local friction coefficient, pressure drop, heat transfer rate, and turbulence kinetic energy. The results revealed that it is possible to improve the thermal performance of the considered system by adopting designs that allow the maximum heat transfer rate with the minimum energy loss. In addition, results show that at the lowest Reynolds number (Re = 10,000), as the height of baffles rises from 0.01 to 0.03 m (growth by 200%), the heat transfer rate augments about 59.09%. Moreover, at the highest evaluated Reynolds number (Re = 87,300), by increasing the height of baffles up to 200%, the heat transfer rate increases by approximately 50.53%. Furthermore, employing a higher number of baffles leads to more heat transfer rates and a significant pressure drop.

Abstract In this numerical work, heat transfer characteristics of humid air in a rectangular channel as solar air heater equipped with V‐shaped ribs has been investigated. The impacts of geometrical parameters of proposed ribs such as height, pitch, and angle relative to air flow direction, as well as relative humidity and Reynolds number of inlet humid air on thermal performance of proposed solar air heater have been evaluated. The numerical results have been achieved using commercial Computational Fluid Dynamics (CFD) code, ANSYS FLUENT 18.2, which works based on finite volume method. Outcomes shows that, over a wide range of operating conditions, utilizing ribs cause thermal boundary layer to separate and reattach, and eventually enhance heat transfer rate. Increasing the rib angle produces stronger secondary flows, leading to higher local velocities and greater heat transfer rate. Moreover, increasing the relative humidity of inlet air from 0% to 50% leads to improve heat transfer by up to 6%. As Reynolds number increases from 4000 to 12,000, average Nusselt number rises by 7.3% and 31.4% for rib pitches of 6 and 16 mm, respectively. The results demonstrate how thermal performance of a solar air heater can be improved by utilizing V‐shaped ribs.

Abstract Background Oral health problems especially dental caries are common in school children, and education programs may help to prevent these conditions. The aim of current study was to examine the effects of an educational program based on a Health Belief Model (HBM) to improve oral health behaviors of elementary school children. Methods A total of 112 children ages 6–12 years old accompanied by one of their parents were randomly assigned to intervention/test and control groups. In the intervention group, five consecutive weekly educational sessions based on the HBM were provided, while the control group received only routine education delivered by the dental clinic. The Decayed, Missing, and Filled Teeth (DMFT) score, papillary bleeding index, and responses to the HBM questionnaire were assessed in the intervention and control groups at baseline and three-month follow-up after the intervention was completed. Within-group and between-group differences were examined using the Student’s t-test and analysis of covariance. Results All HBM domains were improved at follow-up in the intervention group compared to the control group (p

Abstract Background The study aimed to examine the association between perceived weight stigma (PWS), weight status, and eating disturbances. We hypothesized that PWS would partially mediate the association between weight status and eating disturbances among university students. Methods The study involved 705 undergraduate students (379 females and 326 males) recruited from Hong Kong and Taiwan Universities (399 Hong Kong; 306 Taiwan participants). Our sample was from one Hong Kong university (located in Kowloon) and five Taiwan universities (three located in Southern Taiwan, one located in Central Taiwan, and one located in North Taiwan). Participants’ mean age was 20.27 years (SD = 1.79). All participants completed a demographic information sheet, the Three-Factor Eating Questionnaire-18 (TFEQ-R18), and the PWS questionnaire. PROCESS macro models were used to analyze potential mediations. Results We found a significantly higher PWS scores in a high weight group for females and males. There was a significant difference between weight status and eating disturbances. Moreover, PWS partially mediated the association between weight status and eating disturbances for both genders. Conclusions PWS is associated with weight status and eating disturbances, making it an important target for health improvement among young adults. Further studies are needed to corroborate such associations in participants from other societies and cultures.

Background Problematic internet use, especially in people with substance use disorder, may negatively affect their quality of life (QoL). However, it is unclear whether sleep quality is a key mediator in the association between problematic internet use and QoL among people with substance use disorder. Aims This study aimed to investigate the relationship between problematic internet use and QoL and how sleep quality may mediate the association between these two variables. Method Overall, 319 people (85% male) with substance use disorder (mean age 42.2 years, s.d. 8.9) participated in a cross-sectional study in Taiwan. The Smartphone Application-Based Addiction Scale, Bergan Social Media Addiction Scale, Internet Gaming Disorder-Short Form, Pittsburgh Sleep Quality Index and World Health Organization Quality of Life Questionnaire Brief Version were used. Results The prevalence of sleep problems was 56%. There were significant and direct associations between sleep quality and two types of problematic internet use, and between sleep quality and different dimensions of QoL. All types of problematic internet use were significantly and negatively correlated with QoL. Mediated effects of sleep quality in relationships between the different types of problematic internet use and all dimensions of QoL were significant, except for problematic use of social media. Conclusions Different types of problematic internet use in people with substance use disorder may be directly associated with reduced QoL. Sleep quality as a significant mediator in this association may be an underlying mechanism to explain pathways between problematic internet use and QoL in this population.

In this paper, a thermal performance assessment of traditional building constructions and configurations in various Moroccan climates is carried out. This research focuses on enhancing conventional energy efficiency of buildings by investigating the thermal behavior of single clay walls, double clay walls, simple brick walls, and double brick walls based on long-term meteorological data using TRNSYS software. The roof pitch, thermal comfort and discomfort index, and building energy consumption are considered while selecting buildings for each temperature zone. It is noticed that the double brick construction is more efficient in all climatic zones of Morocco. Thus, this material reduces the yearly energy requirement of building by 22% to 25% compared to the usual brick building. On the coldest winter days, a 30° south-facing roof raises the internal temperature by 2.5 °C compared to a horizontal roof. Temperature increases could reduce the air conditioning energy usage by 7% to 32% and overcooling hours by 12% to 21% in cities above 30° N. In addition, the findings are interesting enough to inspire individuals to implement the recommended construction design and study energy efficiency and thermal comfort in Moroccan buildings. Consequently, reducing energy consumption, mitigating climate change, and lowering greenhouse gas emissions.

Background: A mediation model was proposed to explain how religiosity, religious coping, and fear of coronavirus disease 2019 (COVID-19) explained anxiety and depression among older adults. Methods: With the use of a cross-sectional design, the Integrated Health System was used to randomly invite 1000 older adults residing in Qazvin to participate in an online survey. Within the period of November 2020 to January 2021, 696 older Iranian adults (mean age=69.56years; 57.9% women) agreed to participate in the study and reported demographic information as well as measures of religiosity, fear of COVID-19, religious coping, anxiety, and depression. Results: Religiosity had direct effects on depression (B [SE]=-0.087 [0.037]; P=0.023) but not anxiety (B [SE]=-0.063 [0.036]; P=0.072). Moreover, both fear of COVID-19 and religious coping significantly mediated the association between religiosity and anxiety (B [SE]=-0.360[0.035]; p=0.002) and that between religiosity and depression (B [SE]=-0.365 [0.034];P=0.002). Conclusion: During the tough time of COVID-19 pandemic, religiosity and religious coping were protectors for older adults in developing good mental. Therefore, future research is needed to examine education programs that are effective for older adults to obtain correct knowledge concerning COVID-19, including the protective COVID-19 infection behaviors. Therefore, older adults may reduce their fear via their enhanced correct knowledge concerning COVID-19.

The gas pressure in the main network of transmission lines is about 700 to 1000 psi (4826.33 to 6894.76 kPa), which is reduced to 250 psi (1723.69 kPa) at the entrance station of a city. This reduction process, which occurs in the regulator, causes a severe drop in gas temperature. The drop in the gas temperature produces hydrates and even causes the water vapor in the gas to freeze. As a result, there is a possibility that the passage of gas in the regulator is blocked and the gas flow is cut off. By employing heaters (indirect water heaters), the temperature of the gas entering the regulator can be preheated to eliminate the possibility of freezing in the regulator. This heater is fueled with natural gas and it operates for 24 hr a day, especially in the cold seasons. Therefore, one of the main challenges in using this type of heater is its high fuel consumption. Consequently, researchers are looking for a solution to reduce the fuel consumption (natural gas) of gas heaters. In this paper, the heat transfer and fluid flow in a heater of a natural gas pressure reduction plant, the Aliabad Power Plant (Iran), are numerically investigated using a commercial Computational Fluid Dynamics (CFD) code, ANSYS FLUENT 18.2. The considered heater consists of three parts, including (i) gas coils, (ii) a water bath (shell), and (iii) a fire tube. The indirect heat transfer process takes place between the hot liquid flow in the fire tube (combustion exhaust) and the cold liquid flow (natural gas) using the natural convection flows generated in the water bath. Numeric modeling is performed for four different gas mass flows, including 6 × 104, 8 × 104, 1 × 105, and 12 × 105 standard cubic meters per hour (or 16.67, 22.22, 27.78, and 33.33 m3/s). The results indicate that the natural gas outlet temperature achieved to a temperature higher than required. By installing a regulator on the burner, the gas consumption can be reduced, resulting in station cost savings, and also reducing the environmental impacts. The outcomes depict that the maximum possible reductions in monthly gas consumption and economic savings in the proposed system are 67,500 m3 and IRR 25 million at a gas mass flow rate of 60,000 SCMH.

Abstract In this research, it is investigated to numerically evaluate the performance of a polymer electrolyte membrane fuel cell (PEMFC). The performance is investigated through the nonuniformity gradient loading at the catalyst layer (CL) of the considered PEMFC. Computational fluid dynamics is used to simulate a 2D domain in which a steady‐state laminar compressible flow in two‐phase for the PEMFC has been considered. In this case, a particular nonuniform variation inside the CL along the channel is assumed. The nonuniform gradient is created using a nonisothermal domain to predict the flooding effects on the performance of the PEMFC. The computational domain is considered as the cathode of PEMFC, which is divided into three regions: a gas channel, a gas diffusion layer, and a CL. The loading variation inside the catalyst is defined as a constant slope along the channel. In order to find the optimum slope, different slope angles are analyzed. The results point out that the nonuniform loading distribution of the catalyst (platinum) along the channel could improve the fuel cell performance up to 1.6% and 5% for power density and voltage generation, respectively. It is inferred that it is better to use more catalyst in the final section of the channel if the performance is the main concern.

Objectives: Police officers may be at a greater risk for cardiovascular disease (CVD) than the general population due to their highstress occupation. This study evaluated how an educational program based on the health belief model (HBM) may protect police officers from developing CVD. Methods: In this single-group experimental study, 58 police officers in Iran participated in a 5-week intervention based on HBM principles. Outcomes included changes in scores on an HBM scale, time spent on moderate to vigorous physical activity (International Physical Activity Questionnaire), body mass index (BMI), blood lipid profile, blood glucose, and blood pressure. The intervention consisted of 5 HBM-based educational sessions. Follow-up was conducted at 3 months post-intervention. The paired t-test was used to examine differences between baseline and follow-up scores. Results: All aspects of the HBM scale improved between baseline and follow-up (p

Although health behavior theories indicate that fear is effective in activating preventive behaviors, the question of whether COVID-19 severity moderates the association between fear of COVID-19 and preventive behaviors remains unclear. The present study investigated the association between the fear of COVID-19 and preventive behaviors during the COVID-19 community outbreak of two severity levels in Taiwan. Data were obtained regarding the fear of COVID-19 and practice of preventive behaviors from 139 older people (mean age = 71.73 years; 30.2% men) through in-person interviews during a mild COVID-19 outbreak period (baseline assessment). Data from 126 of the 139 participants were obtained again through a telephone interview during a severe COVID-19 outbreak period (follow-up assessment). A significant increase in the fear of COVID-19 (d = 0.39, p < 0.001) and a decrease in preventive behaviors (d = 0.63, p < 0.001) were found in the follow-up assessment. The association between fear of COVID-19 and preventive behaviors was not significant at baseline (r = −0.07, p > 0.05) but became significant at the follow-up assessment (r = 0.32, p < 0.001). The severity of a COVID-19 outbreak may alter older people's psychological status and related behaviors.

Background: Common cancers such as colon, breast, and lung cancer are increasing in developing countries. Objective: This study was conducted to determine 10-year trends and changes in common cancers in patients from a referral hospital in Tehran, Iran. Methods: This cross-sectional study investigated a study population comprising colon, stomach, lung, prostate, and breast cancer patients registered at the cancer center of a referral hospital in Tehran, Iran from April 1, 2007 to the end of March, 2016 (n=4472). Inclusion criteria were a definitive diagnosis of cancer and an age between 15 and 75 years. Data was entered into SPSS (version 18) software and analyzed using the Time Series analysis and Scatter IO graph. Results: Significant correlations (P value P value P value = 0.008) and colon (P value = 0.004) cancers and the decreasing trend in the age of prostate cancer patients (P value = 0.001) were statistically significant. Conclusion: The incidence of cancer has increased over the past 10 years in both genders and ages. It is suggested that future studies should address the causes and factors behind the increasing incidence of common cancers.

Background and Objective: A basic intervention to reduce prevalence of the disease is educating healthy lifestyle particularly for those who are at risk. Present study aimed to assess the effectiveness of two methods of in-situ training and text messaging on blood pressure and lifestyle in a number of military forces susceptible to hypertension. Methods: Using a quasi-experimental study, 100 individuals from military forces were randomly assigned to either in-situ training or text messaging groups. Initial assessment on systolic and diastolic blood pressure as well as lifestyle, body mass index, and physical activity were conducted. Then both groups experienced an educational intervention either by in-situ training or text messaging. Three months after the intervention all variables were assessed again and the data were analyzed by student t-test and Chi-square statistical tests. Results: Systolic blood pressures in average revealed a significant reduction in both groups after intervention compared to baseline. Variables such as weight, body mass index, and physical activity improved in both groups after intervention. Although, the lifestyle total score changed considerably in both groups, in the text-messaging group there was no notable change in domains including health responsibility, spiritual growth, and interpersonal relationships. Conclusion: Text messaging to somewhat may be effective as well as in-situ training to change some health related behaviors and consequently be resulted in blood pressure control.

Background: Dementia is prevalent among older adults and frequently causes dependence on family caregivers. Caregivers may experience a form of stigmatization called affiliate stigma that negatively affects their mental health. The current study sought to establish the psychometric properties of a tool to measure affiliate stigma among Iranian caregivers. Methods: Overall, 541 caregivers of older people with dementia were included in this cross sectional study. Several measures were used to assess the psychometric properties of the Affiliate Stigma Scale (ASS) including the Zarit Burden Interview (ZBI), Hospital Anxiety and Depression Scale (HADS), Short Form 12 (SF-12), Rosenberg Self-Esteem Scale (RSES), and Multidimensional Scale of Perceived Social Support (MSPSS). Convergent and discriminate validity were examined.Exploratory and confirmatory factor analyses were utilized to assess the factor structure of the Ass and a Rasch model was used to evaluate the measurement functioning of the scale. Results: Factor loadings ranged from 0.69 to 0.83 and test-retest reliability from 0.72 to 0.89.Item difficulty ranged widely from -0.66 to 0.89. No considerable differential item functioning (DIF) was found across gender. Confirmatory factor analysis confirmed the three cognitive,effective, and behavioral dimensions of the scale (comparative fit index [CFI]=0.931 to 0.995,root mean square error of approximation [RMSEA]=0.046 to 0.068). Internal consistency was acceptable (Cronbach’s α: 0.88 to 0.94). Significant and positive relationships were found between affiliate stigma and depression, anxiety, and care giving burden (β =0.35 to 0.46). Conclusion: The ASS is a psychometrically valid measure for assessing affiliate stigma in Iranian caregivers of people with dementia. Application of this tool among other caregivers, language sand cultures deserves further study.

Introduction: Dementia is a common cognitive disorder among elderly people requiring special care. Family carers of people with dementia (PWD) may experience mental health issues. This study examined whether spiritual coping is a mediator between the physical function of the patients and mental health status or caregiving burden in their carers. Methods: The caregivers of the PWD (n = 513) were assessed by the Instrumental Activities of Daily Living (IADL) and Spiritual Coping Strategies (SCS) questionnaires at baseline and Zarit Burden Interview, Short Form-12 (SF-12), and Hospital Anxiety and Depression Scale questionnaires at 6 months. The proposed model to assess the mediating effect of SCS was: SCS subscales as mediators, PWD's IADL as an independent variable, and mental health components as dependent variables. Using PROCESS SPSS Macro, the indirect effects of patients' IADL score on mental health-related variables in the caregivers were examined. Results: There were significantly negative associations between IADL score and mental health components (r > 0.3). SCS scores were negatively correlated with depression, anxiety, and caregiving burden (P < 0.001). Four models proposed to explain the indirect effects of spiritual coping on mental health variables revealed the spirituality as a significant mediator (0.28 ≤ R2 ≤ 0.65; P < 0.001). The mediation effect of religious and nonreligious coping on mental health component in SF-12 was the highest (b = 0.57, 95% confidence interval [CI] [0.26, 0.98], b = 1.20, 95% CI [0.63, 1.84], respectively). Conclusion: Spiritual coping may be a mediator between the physical functioning of the patients and carers' mental health status and caregiving burden in Iran. Thus, further investigation is needed to show how these mediators may affect the mental health status of the caregivers.

Abstract Introduction Patients with COVID‐19 often suffer from psychological problems such as post‐traumatic stress disorder (PTSD) and self‐stigmatization that may negatively impact their quality of life and sleep. This study examined mental health as a potential mediating factor linking self‐stigmatization and PTSD to quality of life and sleep. Methods Using a cross‐sectional design, 844 people who had recovered from COVID‐19 were called and interviewed. Data were collected using structured scales. Structural equation modeling was applied to assess fitness of a mediation model including self‐stigma and PTSD as independent factors and quality of life and insomnia as dependent variables. Results Mental health, COVID‐19‐related self‐stigma, and mental quality of life were associated. Insomnia, PTSD, and COVID‐19‐related self‐stigma displayed significant direct associations (r = .334 to 0.454; p

Background. Psychological problems such as stress and anxiety are prevalent among working nurses in the intensive care units (ICUs). This study was aimed at investigating the effects of three skill-based educational programs on stress and anxiety among critical care nurses. Methods. Using a randomized controlled trial, 160 nurses were assigned to four groups including one control and three intervention groups. A standard skill-based educational program was delivered to three intervention groups using booklet, booklet+oral presentation, and booklet+oral presentation+clinical teaching over a period of one month to reduce different types of stress and anxiety. The control group received routine education only. Perceived stress, state anxiety, trait anxiety, and work-related stress were assessed at baseline and three times after the intervention (15 days, 3 months, and 21 months). Repeated-measure analysis of variance was used for data analysis. Results. There was no significant change in the control group in terms of study variables during follow-up assessments, whereas measures of stress and anxiety were reduced after intervention in the trial groups except trait anxiety. Nurses in the mixed-method group (booklet+oral presentation+clinical teaching) showed less stress and anxiety during follow-ups. Although the stress and anxiety scores decreased in the first and second follow-ups, there was no significant reduction in the third follow-up. Conclusions. To improve the mental health and performance of the intensive care unit nurses, knowledge-based and skill-based training programs seem useful. Continuous training may help to maintain the effectiveness of these programs over time.

Due to the high enthalpy of fusion in water, ice storage systems are known as one of the best cold thermal energy storage systems. The phase change material used in these systems is water, thus it is inexpensive, accessible, and completely eco-friendly. However, despite the numerous advantages of these systems, the phase change process in them is time-consuming and this leads to difficulties in their practical application. To solve this problem, the addition of nanomaterials can be helpful. This study aims to investigate the compound heat transfer enhancement of a cylindrical-shaped unit equipped with double helically coiled coolant tubes using connecting plates and nano additives as heat transfer augmentation methods. Complex three-dimensional numerical simulations are carried out here to assess the best heat exchanger material as well as the impact of various nanoparticle types, including alumina, copper oxide, and titania, and their concentrations in the PCM side of the ice storage unit. The influence of these parameters is discussed on the charging rate and the temperature evolution factor in these systems. The results suggest that using nano additives, as well as the connecting plates, together is a promising way to enhance the solidification rate by up to 29.9%.

Abstract Background Polycystic ovary syndrome (PCOS) is a major public health concern worldwide affecting up to one in five women at reproductive age. It is associated with biochemical and hormonal disturbances as well as adverse cosmetic, reproductive, metabolic, and psychological consequences, resulting in worsened quality of life. The aim of the present study is evaluating the quality of life and determining its degrading factors among Iranian women suffering from this syndrome. Methods This cross-sectional study was conducted on 200 PCOS women in Hamadan, Iran. In order to measure quality of life we used the Persian version of Health-related Quality of Life Questionnaire for PCOS (PCOSQ). Descriptive statistics was used to explore the data. In addition linear regression analysis was performed to assess factors affecting health-related quality of life in this population. Results The mean score for quality of life domains (from the greatest to the least serious concern) were: infertility (3.43 ± 1.63), emotions (3.55 ± 1.17), menstrual problems (3.77 ± 1.36), body hair (3.80 ± 2.05) and weight (4.32 ± 1.80), respectively. The higher score represents better function. However, multivariate analysis revealed that hirsutism had the strongest impact on the patients’ quality of life (p

Variable speed wind turbines are commonly used as wind power generation systems because of their lower maintenance cost and flexible speed control. The optimum output power for a wind turbine can be extracted using maximum power point tracking (MPPT) strategies. However, unpredictable parameters, such as wind speed and air density could affect the accuracy of the MPPT methods, especially during the wind speed small oscillations. In this paper, in a permanent magnet synchronous generator (PMSG), the MPPT is implemented by determining the uncertainty of the unpredictable parameters using the extended Kalman filter (EKF). Also, the generator speed is controlled by employing a fuzzy logic control (FLC) system. This study aims at minimizing the effects of unpredictable parameters on the MPPT of the PMSG system. The simulation results represent an improvement in MPPT accuracy and output power efficiency.

In the present work, a parabolic trough solar (PTC) collector with inner helical axial fins as swirl generator or turbulator is considered and analyzed numerically. The three-dimensional numerical simulations have been done by finite volume method (FVM) using a commercial CFD code, ANSYS FLUENT 18.2. The spatial discretization of mass, momentum, energy equations, and turbulence kinetic energy has been obtained by a second-order upwind scheme. To compute gradients, Green-Gauss cell-based method has been employed. This work consists of two sections where, first, four various geometries are appraised, and in the following, the selected schematic of the collector from the previous part is selected, and four various pitches of inner helical fins including 250, 500, 750 and 1000 mm are studied. All the numerical results are obtained by utilizing the FVM. Results show that the thermal performance improvement by 23.1% could be achieved by using one of the proposed innovative parabolic trough solar collectors compare to the simple one. Additionally, the minimum and maximum thermal performance improvement (compare to the case without fins) belong to the case with P = 250 mm by 14.1% and, to the case with P = 1000 mm by 21.53%, respectively.

Background and objective: Reports have revealed a growing tendency towards sedentary lifestyles in all age groups, especially among female adolescents. This study aimed to determine the influence of a social cognitive theory (SCT)-based educational intervention on the physical activity of secondary school students in 2013. Materials and methods: This randomized, controlled field trial was conducted on 132 second- and third-year high school female students. The subjects were divided into control and intervention groups- 68 students with an average of 13 ± 1 years of age in each group. Data collection tools included demographic, physical activity, and SCT-based questionnaires. For data analysis, descriptive statistics were calculated and regression test was performed using SPSS 22 through descriptive statistics and multiple linear regression with 95% confidence interval. Results: In the intervention group, a significant increase was observed in the mean scores of selected SCT concepts (environmental factors, behavioral capacity, outcome expectation, expectancies, observational learning, reinforcement, and self-efficacy), affecting physical activity (p < 0.001). Multiple linear regression in the intervention group showed that daily and weekly physical activity increased to 70.14 and 263.34 minutes, respectively. Conclusion: SCT-based educational intervention has a positive impact on the physical activity of female adolescents. Paper Type: Research Article.

Introduction: In-service training of nurses plays an indispensable role in improving the quality of inpatient care. Need to enhance the effectiveness of in-service training of nurses is an inevitable requirement. This study attempted to design a new optimal model for in-service training of nurses. Methods: This qualitative study was conducted in two stages during 2015-2016. In the first stage, the Grounded Theory was adopted to explore the process of training 35 participating nurses. The sampling was initially purposeful and then theoretically based on emerging concept. Data were collected through interview, observation and field notes. Moreover, the data were analyzed through Corbin-Strauss method and the data were coded through MAXQDA-10. In the second stage, the findings were employed through Walker and Avant’s strategy for theory construction so as to design an optimal model for in-service training of nursing staff. Results: In the first stage, there were five major themes including unsuccessful mandatory education, empowering education, organizational challenges of education, poor educational management, and educational-occupational resiliency. Empowering education was the core variable derived from the research, based on which a grounded theory was proposed. The new empowering education model was composed of self-directed learning and practical learning. There are several strategies to achieve empowering education, including the fostering of searching skills, clinical performance monitoring, motivational factors, participation in the design and implementation, and problem-solving approach. Conclusion: Empowering education is a new model for in-service training of nurses, which matches the training programs with andragogical needs and desirability of learning among the staff. Owing to its practical nature, the empowering education can facilitate occupational tasks and achieving greater mastery of professional skills among the nurses.

Background: Exclusive breastfeeding (EBF) contributes to the health and survival of the newborns. Many factors influence the EBF behavior. This study aimed to identify the determinant factors in order to improve the practice of EBF among Iranian mothers. Methods: A longitudinal study was carried out in 1445 mothers with newborns in Qazvin city, Iran (September 2015-March 2016). Demographic variables as well as the constructs of theory of planned behavior (TBP) were measured by questionnaires. Bivariate analysis using Pearson and Spearman correlation tests with analysis of variance were used to investigate the associations among the variables. Both hierarchal multiple regression and logistic regression were applied to identify potential determinative factors for the EBF. Results: Nearly, 80% (CI: 77.97-82.63%) of the participants had the intention of EBF. All TPB constructs, moral norms, and self-identity were significantly correlated with each other (r: 0.09- 0.40, P < 0.01). Some demographic variables such as age, income, employment and primiparity were also correlated with the EBF (r: 0.11-0.15, P < 0.05). The constructs of the TPB were able to predict the EBF behavior, which account for 49% of the variance in the predicting factors (df = 8, F = 7.70). The self-identity and moral norms accounted for an additional 15% of the variance (df = 10, F = 3.16). Younger mothers with lower socio-economic status were at higher risk of EBF cessation. The intention has a greater impact on the initiation of EBF than perceived behavioral control (PBC) but not for the maintenance of EBF (OR, 2.88 [CI: 2.38-3.48] & 1.13 [CI:1.03- 1.23] vs. OR, 1.27 [CI:1.15-1.39] & 2.66 [CI: 2.02-3.49]). Conclusion: The interventions to promote knowledge, attitude and behavioral control towards the EBF should be considered especially in the young mothers with low socio-economic status.

Thermal energy storage units conventionally have the drawback of slow charging response. Thus, heat transfer enhancement techniques are required to reduce charging time. Using nanoadditives is a promising approach to enhance the heat transfer and energy storage response time of materials that store heat by undergoing a reversible phase change, so-called phase change materials. In the present study, a combination of such materials enhanced with the addition of nanometer-scale graphene oxide particles (called nano-enhanced phase change materials) and a layer of a copper foam is proposed to improve the thermal performance of a shell-and-tube latent heat thermal energy storage (LHTES) unit filled with capric acid. Both graphene oxide and copper nanoparticles were tested as the nanometer-scale additives. A geometrically nonuniform layer of copper foam was placed over the hot tube inside the unit. The metal foam layer can improve heat transfer with an increase of the composite thermal conductivity. However, it suppressed the natural convection flows and could reduce heat transfer in the molten regions. Thus, a metal foam layer with a nonuniform shape can maximize thermal conductivity in conduction-dominant regions and minimize its adverse impacts on natural convection flows. The heat transfer was modeled using partial differential equations for conservations of momentum and heat. The finite element method was used to solve the partial differential equations. A backward differential formula was used to control the accuracy and convergence of the solution automatically. Mesh adaptation was applied to increase the mesh resolution at the interface between phases and improve the quality and stability of the solution. The impact of the eccentricity and porosity of the metal foam layer and the volume fraction of nanoparticles on the energy storage and the thermal performance of the LHTES unit was addressed. The layer of the metal foam notably improves the response time of the LHTES unit, and a 10% eccentricity of the porous layer toward the bottom improved the response time of the LHTES unit by 50%. The presence of nanoadditives could reduce the response time (melting time) of the LHTES unit by 12%, and copper nanoparticles were slightly better than graphene oxide particles in terms of heat transfer enhancement. The design parameters of the eccentricity, porosity, and volume fraction of nanoparticles had minimal impact on the thermal energy storage capacity of the LHTES unit, while their impact on the melting time (response time) was significant. Thus, a combination of the enhancement method could practically reduce the thermal charging time of an LHTES unit without a significant increase in its size.

In recent years, deep neural networks have shown significant progress in computer vision due to their large generalization capacity; however, the overfitting problem ubiquitously threatens the learning process of these highly nonlinear architectures. Dropout is a recent solution to mitigate overfitting that has witnessed significant success in various classification applications. Recently, many efforts have been made to improve the Standard dropout using an unsupervised merit-based semantic selection of neurons in the latent space. However, these studies do not consider the task-relevant information quality and quantity and the diversity of the latent kernels. To solve the challenge of dropping less informative neurons in deep learning, we propose an efficient end-to-end dropout algorithm that selects the most informative neurons with the highest correlation with the target output considering the sparsity in its selection procedure. First, to promote activation diversity, we devise an approach to select the most diverse set of neurons by making use of determinantal point process (DPP) sampling. Furthermore, to incorporate task specificity into deep latent features, a mutual information (MI)-based merit function is developed. Leveraging the proposed MI with DPP sampling, we introduce the novel DPPMI dropout that adaptively adjusts the retention rate of neurons based on their contribution to the neural network task. Empirical studies on real-world classification benchmarks including, MNIST, SVHN, CIFAR10, CIFAR100, demonstrate the superiority of our proposed method over recent state-of-the-art dropout algorithms in the literature.

Thermal energy storage is a technique that has the potential to contribute to future energy grids to reduce fluctuations in supply from renewable energy sources. The principle of energy storage is to drive an endothermic phase change when excess energy is available and to allow the phase change to reverse and release heat when energy demand exceeds supply. Unwanted charge leakage and low heat transfer rates can limit the effectiveness of the units, but both of these problems can be mitigated by incorporating a metal foam into the design of the storage unit. This study demonstrates the benefits of adding copper foam into a thermal energy storage unit based on capric acid enhanced by copper nanoparticles. The volume fraction of nanoparticles and the location and porosity of the foam were optimized using the Taguchi approach to minimize the charge leakage expected from simulations. Placing the foam layer at the bottom of the unit with the maximum possible height and minimum porosity led to the lowest charge time. The optimum concentration of nanoparticles was found to be 4 vol.%, while the maximu possible concentration was 6 vol.%. The use of an optimized design of the enclosure and the optimum fraction of nanoparticles led to a predicted charging time for the unit that was approximately 58% shorter than that of the worst design. A sensitivity analysis shows that the height of the foam layer and its porosity are the dominant variables, and the location of the porous layer and volume fraction of nanoparticles are of secondary importance. Therefore, a well-designed location and size of a metal foam layer could be used to improve the charging speed of thermal energy storage units significantly. In such designs, the porosity and the placement-location of the foam should be considered more strongly than other factors.

Background & Objective: Selfesteem is one of the fundamental factors in academic performance of students and recognizing the variables which impact it may help its improvement The aim of the current study was to assess the impact of factors such as demographic and academic variables inclination toward lifelong learning and learning style on selfesteem among health sciences students Methods: In the present study 209 students of the School of Health of Baqiyatallah University of Medical Sciences (Tehran Iran) were selected to participate in the study using stratified random sampling Data collection tools consisted of a demographic and academic information questionnaire the Rosenberg selfesteem scale (RSES) Kolbs Learning Style Inventory (KLSI) and the Jefferson Scale of Lifelong Learning Data were analyzed using independent ttest oneway ANOVA Pearson correlation test and multiple regression analysis in SPSS software Results: The mean age of participants was 267 ± 84 years and most (94%) of them were men In bivariate analysis factors such as gender daily study time some domains of learning style as well as constructs of lifelong learning were significantly associated with selfesteem In multiple regression analysis variables of gender daily study time abstract conceptualization from learning style domains and beliefs of motivation toward learning (a lifelong learning construct) predicted students selfesteem Approximately 38% of variance in selfesteem was explained using variables included in the regression model Conclusion: Considering that variables such as gender daily study time some learning style domains and inclination toward lifelong learning may be associated with selfesteem to improve students selfesteem in the line with enhancing their academic performance appropriate planning should be undertaken considering these factors Moreover further studies are necessary in this regard to gain more understanding of these factors

Background and objective: Learning style is one of the main components of proper educational planning. The concept of lifelong learning is also one of the valuable concepts regarding professional knowledge and skills, especially for healthcare professionals. The current study was aimed at identifying preferred learning styles among students of health faculty of the Baqiyatallah University of Medical Sciences (BMSU) and assessing the relationship between learning style and lifelong learning. Materials and methods: In this descriptive-analytical cross-sectional study, 209 students from different health disciplines in the School of Health, BMSU were assessed. Data were collected using a demographic questionnaire, Kolb learning style inventory, and the scale of lifelong learning. Chi-square, Fisher exact test, Pearson correlation and one-way ANOVA were used with the help of SPSS 20 for data analysis. Results: The mean age of participants was 26.69 (SD= 8.38) and the majority of them were male (94%). Distribution of learning styles were: diverger (36%), accommodator (34%), assimilator (21%), and converger (10%). Among demographic and academic related variables only grade point average (GDP) significantly was associated with learning styles (p < 0.05). The mean score of lifelong learning was 45.70 (SD= 5.25). The constructs of lifelong learning had significant relationships with active experiencing and reflective observation modes of learning style. The learning styles of assimilator and diverger obtained higher scores of lifelong learning than others. Conclusion: Regarding divergers and accommodators were more frequent than others, it is suggested that these facts be considered for a better educational planning and matching of proper teaching methods. Further research is needed to recognize the relations of learning styles with lifelong learning. Paper Type: Research Article.

Background and objective: Cardiovascular disease is the most common cause of death and a major cause of disability in many countries, including Iran. To reduce the effects of heart attacks and their complications, lifestyle and behavioral modification is needed. In this study, the theory of planned behavior was used to find out if an educational intervention could change the lifestyle of patients with myocardial infarction and how much is its effectiveness. Materials and methods: This was a randomized controlled trial conducted on 80 patients with myocardial infarction who live in the city of Bandar Abbas, Iran. The patients were divided into two groups by random allocation- intervention and control group. Those who were in the intervention group participated in 4 educational sessions (at 50 minutes a session, one session per week) in accordance with the theory of planned behavior. A questionnaire consisting of 3 parts was used to gather the data: demographics, Health Promoting Lifestyle Profile (HPLP II), and a researcher-made scale based on constructs from the theory of planned behavior. Content validity was used for validation and the reliability was assessed using Cronbach's alpha test, and the test-re-test. The questionnaire was completed three times through interview: before the intervention, one month and three months after the intervention. Data were analyzed using Chi-square, RMANOVA, and multiple linear regression. Results: The mean age of the participants was 51.5 7 ±7.70 years; 67% were male. One month and three months after the intervention, a significant improvement in the lifestyle of the intervention group compared with the control group was seen (p 0.001>). Also, based on the constructs of the theory (attitudes, subjective norms, perceived behavioral control, behavioral intention and behavior) one month and three months after the intervention, there were considerable increases in the mean scores of the intervention group than the control group (p 0.001>). Conclusions: The educational program designed based on a theoretical foundation is useful to change attitudes, subjective norms, perceived behavioral control and behavioral intention for a healthy lifestyle among patients with myocardial infarction. It also may improve all aspects of lifestyle in such patients. Therefore, assessing the effectiveness of these theory-based educational interventions may be suggested to improve the lifestyle among other patients. Paper Type: Research Article.

The present study aimed to validate the Chinese version of the Tendency to Avoid Physical Activity and Sport Scale (TAPAS) among university students living in Hong Kong to assess weight and body image concerns. A convenience sample of 787 students (63.5% females; 24.5% overweight) were recruited online. The factor structure of the scale was examined using confirmatory factor analysis (CFA). Multigroup CFA was used to assess measurement invariance across gender and weight categories. The unidimensional structure of the scale was confirmed (?[superscript 2]= 78.046, CFI = 0.996). Factor loading ranged from 0.536 to 0.902, and internal consistency was good ([alpha] = 0.93, [omega] = 0.95). The scale was measurement invariant across gender and weight status using both metric and scalar invariance methods (-0.004<[delta]CFI<-0.002). The scale can help to identify barriers of weight concerns regarding physical activity engagement which would help in the development of preventive interventions.

This paper investigates the cooling performance of nanofluid (NF) mixed convection in a porous I-shaped electronic chip with an internal triangular hot block using Buongiorno’s two-phase model. This type of cavity and hot block geometry has not been studied formerly. The NF was assumed to be a mixture of water and CuO nanoparticles (NP) up to 4% of volume concentration. As most published mathematical models for the thermal conductivity of NF give inaccurate predictions, a new predictive correlation for effective thermal conductivity was also developed with a high accuracy compared to the experimental data. The results showed that any increase in the NP volume concentration enhances the average Nusselt number (Nu¯) and the normalized entropy generation, and reduces the thermal performance of the cavity in all orientations of the hot block. The maximum enhancement in cooling performance was 17.75% and occurred in the right-oriented hot block in the sand-based porous cavity. Furthermore, adding the NP to the base fluid leads to a more capable cooling system and enhances the irreversibility of the process.

The mixed convection two-phase flow and heat transfer of nanofluids were addressed within a wavy wall enclosure containing a solid rotating cylinder. The annulus area between the cylinder and the enclosure was filled with water-alumina nanofluid. Buongiorno’s model was applied to assess the local distribution of nanoparticles in the host fluid. The governing equations for the mass conservation of nanofluid, nanoparticles, and energy conservation in the nanofluid and the rotating cylinder were carried out and converted to a non-dimensional pattern. The finite element technique was utilized for solving the equations numerically. The influence of the undulations, Richardson number, the volume fraction of nanoparticles, rotation direction, and the size of the rotating cylinder were examined on the streamlines, heat transfer rate, and the distribution of nanoparticles. The Brownian motion and thermophoresis forces induced a notable distribution of nanoparticles in the enclosure. The best heat transfer rate was observed for 3% volume fraction of alumina nanoparticles. The optimum number of undulations for the best heat transfer rate depends on the rotation direction of the cylinder. In the case of counterclockwise rotation of the cylinder, a single undulation leads to the best heat transfer rate for nanoparticles volume fraction about 3%. The increase of undulations number traps more nanoparticles near the wavy surface.

The present investigation addressed the entropy generation, fluid flow, and heat transfer regarding Cu-Al 2 O 3 -water hybrid nanofluids into a complex shape enclosure containing a hot-half partition were addressed. The sidewalls of the enclosure are made of wavy walls including cold isothermal temperature while the upper and lower surfaces remain insulated. The governing equations toward conservation of mass, momentum, and energy were introduced into the form of partial differential equations. The second law of thermodynamic was written for the friction and thermal entropy productions as a function of velocity and temperatures. The governing equations occurred molded into a non-dimensional pattern and explained through the finite element method. Outcomes were investigated for Cu-water, Al 2 O 3 -water, and Cu-Al 2 O 3 -water nanofluids to address the effect of using composite nanoparticles toward the flow and temperature patterns and entropy generation. Findings show that using hybrid nanofluid improves the Nusselt number compared to simple nanofluids. In the case of low Rayleigh numbers, such enhancement is more evident. Changing the geometrical aspects of the cavity induces different effects toward the entropy generation and Bejan number. Generally, the global entropy generation for Cu-Al 2 O 3 -water hybrid nanofluid takes places between the entropy generation values regarding Cu-water and Al 2 O 3 -water nanofluids.

The present paper aims to investigate the influence of perforated membrane geometry on the performance of biosensors. For this purpose, a 2-D axisymmetric model of an amperometric biosensor is analyzed. The governing equations describing the reaction-diffusion equations containing a nonlinear term related to the Michaelis–Menten kinetics of the enzymatic reaction are introduced. The partial differential governing equations, along with the boundary conditions, are first non-dimensionalized by using appropriate dimensionless variables and then solved in a non-uniform unstructured grid by employing the Galerkin Finite Element Method. To examine the impact of the hole-geometry of the perforated membrane, seven different geometries—including cylindrical, upward circular cone, downward circular cone, upward paraboloid, downward paraboloid, upward concave paraboloid, and downward concave paraboloid—are studied. Moreover, the effects of the perforation level of the perforated membrane, the filling level of the enzyme on the transient and steady-state current of the biosensor, and the half-time response are presented. The results of the simulations show that the transient and steady-state current of the biosensor are affected by the geometry dramatically. Thus, the sensitivity of the biosensor can be influenced by different hole-geometries. The minimum and maximum output current can be obtained from the cylindrical and upward concave paraboloid holes. On the other hand, the least half-time response of the biosensor can be obtained in the cylindrical geometry.

AbstractThe aim of present study was to determine the relationship between ultrasonic wave velocity and mechanical properties of particleboard panels. For this purpose, homogenous and layering particleboards were made by 0/7 g/cm3 density and 16 mm thickness. After conditioning and preparing samples, ultrasonic wave velocity was measured in different directions of samples. Then modulus of elasticity, modulus of rupture and internal bonding of samples were measured by mechanical test machine. Result indicated that ultrasonic wave velocity of particleboard samples was higher in longitudinal direction than other directions. Relationship between ultrasonic wave velocity and mechanical properties was determined by linear correlation regression. Correlations between ultrasonic wave velocity and modulus of elasticity, modulus of rupture and internal bonding were significant in thickness direction of particleboard samples. Correlations between ultrasonic wave velocity and modulus of elasticity, modulus of rupture and internal bonding were significant in thickness direction of particleboard samples. Correlations between ultrasonic wave velocity and modulus of elasticity, modulus of rupture and internal bonding were significant in thickness direction of particleboard samples.

Objective (s): Stress and coping are one of the most reported problems by adolescents and may be the biggest problem in psychology field that can affect greatly on mental and physical health. the aim of the study was to apprise the stressors, coping strategies and influential factors among male adolescents. Methods: An analytic cross-sectional study was carried out to examine effects of stressors, coping strategies and some demographics variables on perceived stress in 402 male adolescent in Tehran, Iran. Adolescent stress and coping process questionnaire and perceived stress scale were used to collect data. A multivariate regression was performed to assess factors related to perceived stress.Results: The mean age of adolescents was 15.44(SD = 0.68) years. The mean value of perceived stress for the whole sample was 17.99 (SD = 6.02). Cognitive/emotional coping was the most frequent coping style. The findings revealed that there were significant relations between perceived and accumulative stress. In multivariate regression analysis the accumulative stress, social resources (P< 0.01), parent`s education and grade point average (P< 0.05) were found to be significant predictors of perceived stress.Conclusion: The findings suggest that increased level of perceived stress is associated with accumulative stress, social resources and parent`s education. Therefore seems by reducing problems face to adolescents and enhancing parents `knowledge about stress and reinforcing social resources can prevent perceived stress increment. More related studies can show a good perspective.

Introduction : Candida albicans has been isolated in up to 65% of healthy individuals without signs of clinical disease. Mouthwashes can be used for many preventative and therapeutic purposes. This study evaluates the effectiveness of Iranian and foreign mouthwashes against C.albicans as a common fungal flora in the mouth. Materials and method s: In this research, standard strain of C.albicans, ATCC 10231 is used. The suspension is provided by a fresh culture of C.albicans (24 hours) and the OD is read in 530 nm. The C. albicans suspension was cultured on Sabouraud dextrose agar plate. In the next step, two wells created on SDA, filling with mouthwashes (100 µl). After incubation at 37ºC for 24 hours, the inhibition zone was measured. Minimum inhibitory concentration (MIC) and Minimum fungicidal concentration (MFC) of mouthwashes were determined. The data are analyzed by SPSS software, independent T-tests and one sided variance analysis (ANOVA-one way). Results : Findings of our study showed in which agar diffusion, MIC and MFC tests, there are no significant differences between the antifungal effect of the Iranian and foreign mouthwashes on C.albicans (P value>0.05 ). Discussion and conclusion : This study shows that both Iranian and foreign mouthwashes have a good effect against C.albicans, as a common fungal flora in the mouth.

Background: This study aimed to determine whether motivational interviewing (MI) could change dietary habit and body mass index (BMI) in obese/overweight women. Methods: A cluster-randomized controlled study was performed in four health centers in Qazvin, central Iran. In total, 327 obese/overweight women were selected by a multi-stage sampling method and randomly assigned into control and experimental groups. Food frequency (using questionnaire; FFQ), BMI, and metabolic markers including blood pressure, total serum cholesterol and fasting blood glucose levels were measured in all participants. Data were collected twice (before and one year after the MI interventions). Data were analyzed using student t-test, and Stepwise Linear Regression. Results: There was a significant increase in daily consumption of dietary fiber, whole grain products, fruits and vegetables in the MI group (P

High mountains and cold climate in the north-west of Iran are critical factors for the design of optimized District Heating (DH) systems and energy-efficient buildings. It is essential to consider the Life Cycle Cost (LCC) that includes all costs, such as initial investment and operating costs, for designing an optimum DH system. Moreover, considering climate change for accurately predicting the required heating load is also necessary. In this research, a general optimization is carried out for the first time with the aim of a new design concept of a DH system according to a LCC, while considering all-involved parameters. This optimized design is based on various parameters such as ceiling and wall insulation thicknesses, depth of buried water and heating supply pipes, pipe insulation thickness, and boiler outlet temperature. In order to consider the future weather projection, the mentioned parameters are compared with and without climate change effects in a thirty-year period. The location selection was based on the potential of the region for such a system together with the harsh condition of the area to transport the common fossil fuel to the residential buildings. The obtained results show that insulation of walls is more thermally efficient than a roof with the same area in the selected case. In this case, polyurethane is the best material, which can cause a reduction of 59% in the heating load and, consequently, 2332 tons of CO2 emission annually. The most and the least investment payback periods are associated with the polyurethane and the glass wool insulation materials with the amounts of seven and one years. For the general optimization of the DH system, the Particle Swarm Optimization (PSO) method with a constriction coefficient was chosen. The results showed that the optimal thickness of the polyurethane layer for the thermal insulation of the building exterior walls is about 14 cm and the optimal outlet temperature of the boiler is about 95 °C. It can be also concluded that the optimal depth for the buried pipes is between 1.5 to 3 m underground. In addition, for the pipe with elastomeric insulation layer, the thickness of 2 cm is the optimal choice.