Introduction to High‐Temperature Coatings

Coatings for turbine blades possess some attractive properties like oxidation and hot corrosion resistance, maintain their strength, cohesion and etc. High temperature damages divide in three general groups: High temperature corrosion type II (600–850°C), High temperature corrosion type I (750–950°C), Oxidation (950°C and higher). There are three types of high temperature coating: 1- Diffusional coating, 2- Overlay coating, 3- Thermal Barrier coating (TBC). The third type, considered as the overlay coating widely used for critical high temperature conditions like, combustion chamber, rotating blades, etc. The advantages of TBC are: increasing the life time of part, improving the engine efficiency (by increasing TIT (Turbine Inlet Temperature)), decreasing the coolant air flow. TBC coating system contains 4 layer that they totally differs from each other. Four principal segments of TBC layers are: 1- super alloy substrate, 2- aluminum intermediate coating, 3- TGO (Thermally Grown Oxide), 4- ceramic final coating. Some advantages of thermal sprayed coatings are: 1- making thick coating with high velocity, 2- low cost recoating damaged regions, 3- covering a wide variety of materials that can be melt without decomposition, 4- mechanically joint coating particles to the substrate, 5- applicable either manually or automatically

Adolescent transport and unintentional injuries: a systematic analysis using the Global Burden of Disease Study 2019

Background: Globally, transport and unintentional injuries persist as leading preventable causes of mortality and morbidity for adolescents. We sought to report comprehensive trends in injury-related mortality and morbidity for adolescents aged 10–24 years during the past three decades. Methods: Using the Global Burden of Disease, Injuries, and Risk Factors 2019 Study, we analysed mortality and disability-adjusted life-years (DALYs) attributed to transport and unintentional injuries for adolescents in 204 countries. Burden is reported in absolute numbers and age-standardised rates per 100 000 population by sex, age group (10–14, 15–19, and 20–24 years), and sociodemographic index (SDI) with 95% uncertainty intervals (UIs). We report percentage changes in deaths and DALYs between 1990 and 2019. Findings: In 2019, 369 061 deaths (of which 214 337 [58%] were transport related) and 31·1 million DALYs (of which 16·2 million [52%] were transport related) among adolescents aged 10–24 years were caused by transport and unintentional injuries combined. If compared with other causes, transport and unintentional injuries combined accounted for 25% of deaths and 14% of DALYs in 2019, and showed little improvement from 1990 when such injuries accounted for 26% of adolescent deaths and 17% of adolescent DALYs. Throughout adolescence, transport and unintentional injury fatality rates increased by age group. The unintentional injury burden was higher among males than females for all injury types, except for injuries related to fire, heat, and hot substances, or to adverse effects of medical treatment. From 1990 to 2019, global mortality rates declined by 34·4% (from 17·5 to 11·5 per 100 000) for transport injuries, and by 47·7% (from 15·9 to 8·3 per 100 000) for unintentional injuries. However, in low-SDI nations the absolute number of deaths increased (by 80·5% to 42 774 for transport injuries and by 39·4% to 31 961 for unintentional injuries). In the high-SDI quintile in 2010–19, the rate per 100 000 of transport injury DALYs was reduced by 16·7%, from 838 in 2010 to 699 in 2019. This was a substantially slower pace of reduction compared with the 48·5% reduction between 1990 and 2010, from 1626 per 100 000 in 1990 to 838 per 100 000 in 2010. Between 2010 and 2019, the rate of unintentional injury DALYs per 100 000 also remained largely unchanged in high-SDI countries (555 in 2010 vs 554 in 2019; 0·2% reduction). The number and rate of adolescent deaths and DALYs owing to environmental heat and cold exposure increased for the high-SDI quintile during 2010–19. Interpretation: As other causes of mortality are addressed, inadequate progress in reducing transport and unintentional injury mortality as a proportion of adolescent deaths becomes apparent. The relative shift in the burden of injury from high-SDI countries to low and low–middle-SDI countries necessitates focused action, including global donor, government, and industry investment in injury prevention. The persisting burden of DALYs related to transport and unintentional injuries indicates a need to prioritise innovative measures for the primary prevention of adolescent injury. Funding: Bill & Melinda Gates Foundation

The Effect of Self-Differentiation Therapy on Assertiveness of Female Students of Allameh Tabataba’i University

The present study aims to study the effectiveness of selfdifferentiation therapy on assertiveness of female students of Allameh Tabataba’i University. The research employed a semi-experimental design with pre-test and post-test. Using convenience sampling method, 20 subjects were selected from among first-year undergraduate female students of the Faculty of Psychology and Educational Sciences, Allameh Tabataba’i University. The sample populated was randomly assigned into two groups, namely experiment and control groups, each consisting of 10 people. The experiment group received 8 sessions of self-differentiation therapy. The control group received no intervention. The data was analyzed using Covariance analysis. The results showed that self-differentiation therapy was effective on improvement of assertiveness (P<0.01). Generally, it can be concluded that self-differentiation therapy helped to increase the level of assertiveness of the participants

Phytotoxicity of encapsulated essential oil of rosemary on germination and morphophysiological features of amaranth and radish seedlings

Recently, there has been a growing interest in plant-derived substances and their environmentally-friendly application to crops, as alternatives to the use of chemical herbicides. Here, the essential oil (EO) of rosemary (Rosmarinus officinalis L.) was analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC–MS). The EO was then evaluated to examine its phytotoxic effects under greenhouse conditions. For the first time in the scientific literature, starch was used in order to encapsulate the EO and to make it function as a bio-herbicide which, accordingly, would be released slowly in the soil as a result of its encapsulation. The EO was successfully encapsulated in the starch matrix for the first time and the released profile of the EO was evaluated as a core material. This study revealed that the encapsulation efficiency (EE) and the loading capacity (LC) of the starch matrix loaded with EO were about 99.99 and 5.26%, respectively, when encapsulation occurred by using 1 g of EO per 1 g of starch. The starch-coated capsules containing the EO were mixed with pot soil at various concentrations (0, 0.5, 2, 3.5 and 5 g of capsules per kg of soil). Furthermore, the inhibitory effects of the encapsulated EO (ENCEO) were tested on the germination rate and percentage of seeds, fresh and dry weights of the roots and stems, root length, leaf area, chlorophyll content, proline content, hypocotyl length and diameter in radish, as well as the relative membrane permeability (RMP) of the leaf in amaranth (Amaranthus retroflexus) and radish (Rhaphanus sativus) under greenhouse conditions. The results showed that the increase in the concentration of ENCEO caused the significant decrease in germination rate and percentage, leaf area, fresh and dry weights of roots and stems, root length and chlorophyll content in both species (P ≤ 0.05). However, there was a significant increase in the amounts of proline and RMP (P ≤ 0.05) in the tested species

Environmental disclosure quality and risk: the moderating effect of corporate governance

Purpose: The purpose of this article is to investigate the relationship between environmental disclosure quality (EDQ) and risk and to further examine whether corporate governance (CG) practices moderate this relationship. Design/methodology/approach: This study uses a set of unique, hand collected data (from 2011 to 2016) to measure EDQ for a sample of 762 firm-years Iranian listed companies. Ordinary least squares regression analysis is performed in testing hypotheses after controlling for a variety of firm, industry and year effects. Moreover, several analyses are performed to establish the robustness of the findings. Findings: The results indicate a negative association between EDQ and firm risk. While board independence moderates this relationship, other CG practices such as CEO duality and board size do not show any effects on the relationship between EDQ and risk. The results remain robust after performing sensitivity tests and under various specifications, including the fixed-effects panel data and Heckman two-stage regressions. Research limitations/implications: Results are from a sample of firms from one country. Practical implications: The results have implications for policymakers, legislators and corporate executives, as environmental initiatives are gaining more attention worldwide. Social implications: Sustainability initiatives in the areas of environmental and social performance and disclosure are gaining global attention. This study addresses the link between firm risk and EDQ. Originality/value: This study contributes to the literature by shedding light on the relationship between corporate risk-taking and EDQ in the context of a developing economy

Observer-Based Backstepping Sliding Mode Control Design for Microgrids Feeding a Constant Power Load

This paper deals with the problem of controller design for DC microgrids that feed constant power loads. To design the proposed controller, first by the use of the exact feedback linearization approach, the linear model of Brunovsky\u27s canonical representation of the system has been obtained to address the nonlinearity problem of the system. Then, the desired control technique is developed by a combination of sliding mode and backstepping control approaches in which a nonlinear disturbance observer is utilized to estimate the disturbance. The overall stability of the system is analyzed based on the Lyapunov approach. A suitable and practical sliding surface is one of the controller strengths that allow the bus voltage to track the reference voltage with high accuracy and fast transient response. Finally, to prove the mentioned claims, an experimental setup has been constructed and the proposed controller is implemented. The experimental results have been analyzed and error analysis is performed. The results confirm the superiority of the proposed controller compared to state-of-the-art controllers

The Barriers, Challenges, and Strategies of COVID-19 (SARS-CoV-2) Vaccine Acceptance: A Concurrent Mixed-Method Study in Tehran City, Iran

Acceptance and willingness to receive the vaccine are among the main factors in the success or failure of a health system in implementing the vaccination program. The present study was conducted in Tehran, the political and economic capital of Iran, to determine the acceptance of the COVID-19 vaccine and identify its associated factors, and explain the most important barriers and acceptance strategies for vaccination. This research was a concurrent quantitative and qualitative mixed-method study. In the quantitative part, 1200 individuals aged more than 18 years were selected from the households in 22 districts of Tehran City, with a multistage stratified cluster sampling method. Two questionnaires were used to evaluate the acceptance of the COVID-19 vaccine and vaccine acceptance determinants. The qualitative content analysis method addressed the influencing factors, as well as challenges and strategies related to the acceptance of the COVID-19 vaccine in four groups of Tehran inhabitants: the elderly, people with underlying diseases, healthcare workers, and the general population. The related data were simultaneously collected by applying in-depth semi-structural interviews and a data analysis process. Furthermore, we used the Graneheim and Lundman method for data analysis. We analyzed the data of 1200 people with a mean (SD) age of 46.4 (11.1) years, and approximately 58% of them were men. The vaccine acceptance was 83.6% (95% CI: 81.3–85.9). Among those who welcomed vaccination, 58% preferred the imported vaccines, 25% the Iranian ones, and 17% both. There was a significant association between the variables of age (adjusted odds ratio [AOR] = 1.72, 95% CI: 1.01–2.93), being single (AOR = 0.54, 95% CI: 0.41–0.91), moderate pharmacotherapy adherence (AOR = 0.58, 95% CI: 0.4–0.85), and the willingness to receive COVID-19 vaccine. Qualitative study after interviewing 45 people from four study groups showed an insufficient social trust in healthcare system officials, pharmaceutical and vaccine production companies; distrust in the effectiveness of the vaccines, concerns about the vaccine adverse effects, being tracked by microchips after vaccination, traditional anti-vaccination movements, the feeling the inessentiality of vaccination, and uncertainty about the fair distribution of the vaccine. These concerns were the main challenges addressed by the study groups. A good proportion of Tehran residents reported their willingness to receive the COVID-19 vaccine. Additionally, they expressed their critical concerns, such as insufficient trust in the healthcare system, vaccine safeties, and adverse effects that were the significant barriers to vaccine acceptance. It seems that conflicts raised by the shortage of vaccines and their import due to the sanctions have led to intense desire and demand in the general population, and especially the elderly, for vaccination. Besides, vaccination phobia in some individuals requires further investigations

The Barriers, Challenges, and Strategies of COVID-19 (SARS-CoV-2) Vaccine Acceptance: A Concurrent Mixed-Method Study in Tehran City, Iran

Acceptance and willingness to receive the vaccine are among the main factors in the success or failure of a health system in implementing the vaccination program. The present study was conducted in Tehran, the political and economic capital of Iran, to determine the acceptance of the COVID-19 vaccine and identify its associated factors, and explain the most important barriers and acceptance strategies for vaccination. This research was a concurrent quantitative and qualitative mixed-method study. In the quantitative part, 1200 individuals aged more than 18 years were selected from the households in 22 districts of Tehran City, with a multistage stratified cluster sampling method. Two questionnaires were used to evaluate the acceptance of the COVID-19 vaccine and vaccine acceptance determinants. The qualitative content analysis method addressed the influencing factors, as well as challenges and strategies related to the acceptance of the COVID-19 vaccine in four groups of Tehran inhabitants: the elderly, people with underlying diseases, healthcare workers, and the general population. The related data were simultaneously collected by applying in-depth semi-structural interviews and a data analysis process. Furthermore, we used the Graneheim and Lundman method for data analysis. We analyzed the data of 1200 people with a mean (SD) age of 46.4 (11.1) years, and approximately 58% of them were men. The vaccine acceptance was 83.6% (95% CI: 81.3–85.9). Among those who welcomed vaccination, 58% preferred the imported vaccines, 25% the Iranian ones, and 17% both. There was a significant association between the variables of age (adjusted odds ratio [AOR] = 1.72, 95% CI: 1.01–2.93), being single (AOR = 0.54, 95% CI: 0.41–0.91), moderate pharmacotherapy adherence (AOR = 0.58, 95% CI: 0.4–0.85), and the willingness to receive COVID-19 vaccine. Qualitative study after interviewing 45 people from four study groups showed an insufficient social trust in healthcare system officials, pharmaceutical and vaccine production companies; distrust in the effectiveness of the vaccines, concerns about the vaccine adverse effects, being tracked by microchips after vaccination, traditional anti-vaccination movements, the feeling the inessentiality of vaccination, and uncertainty about the fair distribution of the vaccine. These concerns were the main challenges addressed by the study groups. A good proportion of Tehran residents reported their willingness to receive the COVID-19 vaccine. Additionally, they expressed their critical concerns, such as insufficient trust in the healthcare system, vaccine safeties, and adverse effects that were the significant barriers to vaccine acceptance. It seems that conflicts raised by the shortage of vaccines and their import due to the sanctions have led to intense desire and demand in the general population, and especially the elderly, for vaccination. Besides, vaccination phobia in some individuals requires further investigations