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The purpose of this research is to extract the natural frequencies of a circular plate containing a central hole reinforced with boron nitride nanotubes (BNNTs) and containing piezoelectric layers.

A unit cell shall be taken into account for the simulation of BNNT's volume fraction. A rectangular micromechanical model is used to obtain the mechanical properties of unit cell of piezoelectric fiber-reinforced composite (PFRC). The three-dimensional (3D) elasticity method is presented to provide the relationship between displacements and stresses. The one-dimensional differential quadrature method (1D-DQM) and the state-space methodology are combined to create the semi-analytical technique. The state-space approach is utilized to implement an analytical resolution in the thickness direction, and 1D-DQM is used to implement an approximation solution in the radial direction. The composite consists of a polyvinylidene fluoride (PVDF) matrix and BNNTs as reinforcement.

A study on the PFRC is carried, likewise, the coefficients of its properties are obtained using a micro-electromechanical model known as the rectangular model. To implement the DQM, the plate was radially divided into sample points, each with eight state variables. The boundary situation and DQM are used to discretize the state-space equations, and the top and bottom application surface conditions are used to determine the natural frequencies of the plate. The model's convergence is assessed. Additionally, the dimensionless frequency is compared to earlier works and ABAQUS simulation in order to validate the model. Finally, the effects of the thickness, lateral wavenumber, boundary conditions and BNNT volume fraction on the annular plate's free vibration are investigated. The important achievements are that increasing the volume fraction of BNNTs increases the natural frequency.

The micromechanical “XY rectangle” model in PFRC along with the three-dimensional elasticity model is used in this literature to assess how the piezoelectric capabilities of BNNTs affect the free vibration of polymer-based composite annular plates under various boundary conditions.

The Mongol invasion caused widespread destruction in many cities; this research studies the destruction course of cities after the Mongol invasion and their reconstruction during the reform period, the change that it brought to the cityscapes of Iranian cities and the difference between the urbanscape of the cities that flourished or were re-established after these destructions with the cities prior to them.

The method of research used is historical interpretation/analysis. The historical texts of pre-Mongolian Persia and texts from the Ilkhanid era are studied, references to the shapes and appearances of Iranian cityscapes are classified, and with the help of contemporary interpretations and existing physical evidence, the urbanscape of these two periods are redrawn and compared to each other.

The selection of scenic meadows to build the city, the presence of many gardens in the urban patterns and the construction of satellite towns around large cities have been the effects of the Mongol tradition of (Yurt) tent-dwelling on Iranian cities during the reforms. The declining population and the massive migration of artists together with the rethinking of the rulers made the existence of dense cities with multi-storey houses less likely. The tradition of pre-designing the city and buildings and designing open and right-angled pathways continued after the Mongol invasion.

The prevailing belief is that during the Mongol era, only the destruction of cities took place and the Mongols did not create any cities and had no influence on urban development. This research aims to challenge that.

Hepatitis C is one of the major health issues in both developed and developing countries. Hepatitis C virus (HCV) infection is more common in prisoners than in the general population. The purpose of this study was to determine the prevalence of HCV and its associated risk factors in Iranian male prisoners in Tehran.

In this cross-sectional study, the authors investigated the frequency and risk factors of hepatitis C infection among male prisoners in the Great Tehran Prison. Information on risk factors including the length of imprisonment, previous history of imprisonment, history of drug injection, history of tattooing, history of piercing, history of high-risk sex and family history of hepatitis C were extracted from patients’ records. To evaluate HCV status, blood samples were collected and tested.

In this study, 179 participants were included. Nine participants (5.0%, 95% CI, 2.3-9.3) were positive for hepatitis C. HCV infection was not significantly associated with age, marital status, education, previous history of imprisonment, length of imprisonment, piercing and high-risk sex; however, there was a significant association between a history of tattooing and a history of injecting drug use and Hepatitis C.

The prevalence of hepatitis C among male prisoners in Great Tehran Prison was 5% in this study, similar to recent studies on prisoners in Tehran. A history of drug injections as well as tattooing were the most important risk factors for hepatitis C in male prisoners.

This study aims to investigate the direct effect of intellectual capital on the organizational performance of Indonesian state-owned enterprises (SOEs) and their subsidiaries. Furthermore, it also examines whether the relationship is mediated by open innovation and moderated by organizational inertia.

This study is designed as quantitative research. A survey method is employed to collect data by distributing questionnaires to the upper-level managers of the SOEs and their subsidiaries. A total of 293 questionnaires were distributed to the respondents, and 97 responses were obtained for further analysis. The partial least square structural equation modeling (PLS-SEM) is used to test the hypotheses. A mediation-moderation research framework is employed.

The results show that intellectual capital has a positive effect on organizational performance. Further results also demonstrate that open innovation mediates the intellectual capital–organizational performance relationship and organizational inertia moderates the intellectual capital–organizational performance relationship. Theoretically, the findings contribute to the resource-based view (RBV) and knowledge-based view (KBV) by providing empirical evidence of the importance of distinctive internal resources in achieving superior organizational performance. Practically, the findings provide strategic information for managers that they should properly manage intellectual capital, open innovation and organizational inertia because of their effects on organizational performance.

First, this study addresses the previous research gaps by confirming that intellectual capital has a positive effect on organizational performance in the research setting of an emerging market. Second, by using a mediation research framework, this study shows that open innovation mediates the relationship between intellectual capital and organizational performance. Third, by using a moderating research framework, this study also reveals that organizational inertia weakens the relationship between intellectual capital and organizational performance. Those associations are rarely researched.

The citizen-shareholder approach in the capital market is considered a knowledge-enhancing and emerging concept in financial and accounting offerings. Its reliable background in management and human sciences makes it an essential basis for protecting the interests of shareholders and investors. Shareholders are considered a necessary part of the social platforms that are companies and regulatory institutions in the capital market; beyond being obligated to protect their material and intellectual rights, they are responsible for developing norms and facilitating investment values and gaining trust through mutual interactions based on respect for their interests. The purpose of this paper is to perform interactive qualitative analysis of the requirements for protecting the rights of citizens of capital market shareholders.

The methodology of the research is mixed, so that in the qualitative part, through content screening, the dimensions related to the protection of the citizen rights of the capital market shareholders were identified through a systematic review of 10 research in the period of 2017–2022. Then, the reliability of the specified dimensions was examined through Delphi analysis; in the quantitative part of the research, the criteria identified through the pairwise comparison matrix were first determined by the level of their relationships to determine based on the pattern of systemic representation of drivers and the consequences of requirements to protect the rights of citizens of capital market shareholders.

The research results in the qualitative part indicated the existence of 12 primary themes; during the two stages of Delphi analysis, three themes were removed, and a total of nine themes entered the quantitative phase. The results in a quantitative part indicate the creation of specialized and active committees of the board of directors as the primary driver and the reliability and timely disclosure of information in the long term as a systemic consequence.

To the best of the authors’ knowledge, this is the first research that presents the new concept of citizen shareholders to strengthen the requirements of protecting the rights of shareholders in the capital market while developing new theoretical literature.

The purpose of this paper is to provide an overview of the antimicrobial and antioxidant properties of postbiotics and the use of postbiotics to increase the shelf life and quality of food.

In this review paper, all articles from five electronic databases containing Google Scholar, Web of Science, PubMed, Scopus and Science Direct were considered and selected according to the purpose of the study.

In addition to improving food safety and increasing its shelf life, natural food preservation using biological preservatives also has a positive effect on improving consumer health. As a result, protection using natural antioxidants and antimicrobial agents seems essential. Postbiotics, having favorable characteristics such as nontoxicity, long shelf life and ease of standardization and transportation, are known as suitable antioxidant and antimicrobial, and there is an interest in making antioxidant and antimicrobial active films containing postbiotics to delay spoilage, increase the shelf life of perishable foods without changing their sensory characteristics.

Postbiotic refers to all soluble factors that are either secreted from living probiotic cells or released after cell lysis. These compounds include enzymes, peptides, polysaccharides, organic acids, teichoic acids and cell surface proteins, and their effects have been proven to improve some human and animal diseases. Probiotic bacteria must survive unfavorable conditions such as processing, storage, distribution, preparation and the digestive system to exert their health-giving effects, whereas their metabolites (postbiotics) have overcome these adverse conditions well and may be a good substitute for probiotics.

The purpose of this paper is to review studies on mathematical optimization of the sustainable gasoline supply chain to help decision-makers understand the current situation, the exact dimensions of the problem and the models provided in the literature. So, a more realistic mathematical optimization model can be achieved by fully covering all dimensions of the supply chain of this product.

To evaluate and comprehend the mathematical optimization of the sustainable gasoline supply chain research area, a systematic literature review is undertaken that covers material collection, descriptive analysis, content analysis and material evaluation steps. Finally, based on this process, 69 related articles were carefully investigated.

The results of the systematic literature review show the main areas of the published papers on mathematical optimization of sustainable gasoline supply chain problems and the gaps for future research in this field presented based on them.

This approach is subject to limitations because the protocol of the systematic review of the research literature only included searching for the considered combination of keywords in the Scopus and ProQuest databases. Furthermore, the protocol used in this paper restricts documents to English.

The results have significant implications for both academicians and practitioners in this field. It can be useful for academics to comprehend the gaps and future trends in this field. Also, for practitioners, it can be useful to identify and understand the parts of the mathematical optimization model, which can help them model this problem effectively and efficiently.

No systematic literature review has been done in this field by considering gasoline to the best of the authors’ knowledge and delivers new facts for the future development of this field.

This study aims to investigate the perceptions of Iranian English teachers about their teaching efficiency through a specific practicum course, namely, language teaching methodology. Drawing on a marketing education perspective, the researchers sought to measure the service quality offered in universities by examining teachers’ satisfaction with the curriculum.

Using quantitative gap analysis, the study evaluated the knowledge and skills of teachers in their preservice education regarding the perceived importance of knowledge and skills required in practice. The study involved 120 English as a foreign language teachers holding a BA degree from two universities in Iran, each with two to four years of teaching experience in the private sector. Data were collected using a 40-item semantic differential Likert scale developed by the researchers. The scale incorporated two components that assessed teachers’ perceived importance of knowledge and skills and their preservice educational preparation.

The findings revealed that most participants were overprepared in various items. However, there were some gaps in content knowledge and skills. Reasons for these gaps mainly included having adequate experience of and/or familiarity with course content, having completed relevant courses beforehand and imitating role model teachers. Teachers’ underpreparation was attributed to their lack of preparation in some specific subjects due to limited skill, practice, motivation, experience and familiarity with that content area.

This study explores the perceived knowledge and skills of Iranian English teachers and provides empirical insights into higher education service quality and customer satisfaction.

This study aims to examine the recent literature on health-promoting behavior, health needs and associated factors among older adults.

An massive search of five databases involving documents in the past decade was commenced.

This review showed a significant relationship between older adults’ demographic characteristics (marital status, income, chronic disease, education level and smoking status) and health-promoting behaviors. This review showed that older adults with a high level of education, high income, chronic diseases and smoker and married older adults are associated with better health-promoting behaviors.

The result of the current review supports the Pender Health Promotion Model that individual personal characteristics can affect the level of engagement in health-promoting behaviors. Assessing the health-promoting behaviors of older adults can help in identifying their health needs.

The purpose of this study is to analyze the correlation between a company’s efforts to reduce carbon emissions and its actual carbon performance. Additionally, the study investigates how female decision-makers may influence this relationship as moderators.

This study uses a data set consisting of 1,258 observations from companies listed on the STOXX Europe 600 index between 2009 and 2021. The study applies the ordinary least squares technique to investigate the connection between carbon reduction initiatives and actual carbon performance, taking into account the potential impact of board and executive gender diversity. To ensure the reliability of the findings, subsample analysis and a two-step generalized method of moments technique were used.

The results show a significant negative association between a firm’s commitment to environmental initiatives and its carbon emission intensity. Furthermore, the study explores the moderating effect of board and executive gender diversity on this relationship and finds that gender diversity has a significant negative impact on the relationship between emissions reduction initiatives and carbon emissions.

The study has practical implications for corporate sustainability efforts. It highlights the importance of implementing carbon reduction initiatives to effectively mitigate carbon emissions. This emphasizes the need for sustainable business strategies that prioritize environmental initiatives. Additionally, the study underscores the positive impact of gender diversity in leadership positions on carbon reduction efforts. Policymakers and organizations can leverage these findings to promote gender diversity and enhance sustainability practices.

It provides evidence-based insights for policymakers to develop specific policies and action plans in priority areas such as climate change and emissions reduction. It also highlights the positive influence of gender diversity in corporate leadership on environmental initiatives, promoting inclusivity and equality in sustainability practices.

This study brings originality by investigating the direct impact of a company’s carbon reduction initiatives on its carbon performance. It also explores the moderating effect of board and executive gender diversity on this relationship. The study provides evidence-based insights for policymakers and applies neo-institutional theory to analyze the interplay between carbon reduction initiatives, carbon emissions and gender diversity in executive and board positions.