درخت حوزه‌های تخصصی

Objectives: This study aims to investigate the impact of the COVID-19 crisis on the speed of adjustment of trade credit among companies listed on the Tehran Stock Exchange (TSE), with particular attention to the moderating role of managerial ability. Methodology/Design/Approach: The research sample includes 131 listed firms observed over a ten-year period (2013–2022), selected using the systematic exclusion method. A multivariable linear regression model was employed to test the research hypotheses. The model developed by Luo (2022) was used to measure the speed of adjustment of trade credit before and after the COVID-19 outbreak, while the model of Demerjian et al. (2012) was applied to evaluate managerial ability. Findings: The results indicate that, on the demand side of trade credit, the speed of adjustment of accounts payable increased by approximately 17% after the COVID-19 outbreak, with capable managers further accelerating this trend. Conversely, on the supply side, the speed of adjustment of accounts receivable declined by nearly 50%. This decline is attributed to rising inflation and economic instability during the post-crisis period, which led managers— including highly capable ones—to deliberately slow the adjustment of credit sales in order to benefit from inventory retention and mitigate risks in inflationary conditions. Innovation: This study extends the literature by demonstrating how crises such as COVID-19 reshape trade credit dynamics in emerging markets. It highlights the asymmetric effects on the supply and demand sides of trade credit and underscores the role of managerial ability in adapting financial policies under conditions of uncertainty and economic instability.

This study investigates the role of economic factors such as total annual water withdrawal, total renewable energy consumption, total greenhouse gas emissions, and waste generation in shaping the trajectory of the circular economy. Utilizing a nonlinear multilevel regression model with combined fixed and random effects, the research examines the impact of these variables on the circular economy index in Iran over the period 1993 to 2023. The choice of this model is justified by its ability to incorporate both fixed effects (such as average variable levels) and random effects (to account for unobserved heterogeneity across observations or units). The results indicate that among the factors influencing the circular economy, renewable energy consumption has a positive and statistically significant effect on circular economy index, with a coefficient of 0.004. In other words, higher renewable energy consumption is associated with improvements in the circular economy index, underscoring the positive role of clean and renewable energy in promoting sustainable economic development. Conversely, water withdrawal, greenhouse gas emissions, and waste generation negatively impact the circular economy, with coefficients of -0.091, -0.02, and -0.003, respectively. This implies that increased unsustainable resource use (such as water extraction), higher greenhouse gas emissions, and greater waste generation hinder the development of a circular economy. Strategic and targeted investment in water-efficient technologies, renewable energy development, greenhouse gas mitigation, and comprehensive waste management can serve as fundamental pillars for advancing the circular economy.

I take paraconsistent logic to be one of the most important and significant developments in logic and metaphysics in the last 100 years, challenging, as it does, one of the deepest dogmas entrenched in Western philosophy: that consistency is a sine qua non of rational thought. This paper looks back at the modern development of the subject. It is partial, in that it concerns only what one might call the formative years of the subject. It is personal, in that I describe my own involvement in some areas. The first part of the paper concerns paraconsistency as such. It starts with the name itself, its origin and its meaning. After a brief look at the history before the 20th century, it notes the work of the early pioneers: Orlov, Jaśkowski, Halldén, Smiley, Val and Richard Routley, and da Costa. For each of these, it describes both what motivated them, and the techniques they used in their constructions. It then describes the early reception of paraconsistency, and the way that it became a global movement. Next, the paper turns to dialetheism, again starting with the name itself and its meaning. After a brief look at the history of the notion before the 20th century, it describes the origin of the modern subject in the work of Richard Routley/Sylvan and myself. Finally, it turns to one of the major applications of paraconsistency: inconsistent mathematics—and specifically set-theory, arithmetic, and geometry. It notes the work of da Costa, Routley/Sylvan, Meyer, Mortensen, and others, describing some of the results concerning the mathematical theories they investigated.

Social adjustment functions as a connecting bridge in human interactions. High self-worth, by enhancing employees’ communication and interpersonal skills, provides a foundation for greater psychological well-being. In fact, a major portion of self-worth’s influence on mental well-being is realized through an individual’s capacity to establish constructive relationships with others in the workplace. The present study aimed to examine the mediating role of social adjustment in the relationship between self-worth and psychological well-being among employees. This research was applied in purpose and employed a descriptive-correlational design using structural equation modeling (SEM). The statistical population consisted of all 240 female employees of Zahedan Health Center in 2024, all of whom were included in the study through a census sampling method. Data were collected using Bell Adjustment Inventory (1961), Contingencies of Self-Worth Scale by Crocker et al. (2003), and Ryff’s Psychological Well-Being Scale (1995). Data analysis was conducted using SPSS 20 and LISREL software. Path analysis results revealed significant positive correlation between social adjustment and psychological well-being (r = 0.79, p < 0.01), between self-worth and social adjustment (r = 0.57, p < 0.01), and between self-worth and psychological well-being (r = 0.48, p < 0.01). The Sobel test yielded a Z-value of 12.45, which exceeded the critical value of 1.96. Therefore, at a 95% of confidence level, it can be concluded that social adjustment plays a significant mediating role in the relationship between self-worth and employees’ psychological well-being.