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This study examines how Entrepreneurial Orientation (EO) influences the economic performance (ECONP) of manufacturing SMEs in Yemen, with environmental performance (EP) tested as a mediating factor. Unlike prior research that has largely focused on developed economies, this paper provides new insights into sustainability pathways in resource-constrained and institutionally unstable contexts. Grounded in Contingency Theory and the Resource-Based View, the study employs a quantitative design using a cross-sectional survey of 199 Yemeni manufacturing SMEs. Structural Equation Modeling with Partial Least Squares (PLS-SEM) was applied to test the hypothesized relationships. Results indicate that EO positively affects both EP and ECONP, and that EP partially mediates the EO–ECONP link. This finding underscores the strategic importance of environmental practices for economic resilience in developing-country SMEs. The novelty of this study lies in being the first to empirically test the mediating role of EP in the EO–ECONP relationship within Yemeni SMEs, thereby extending sustainability research to a context that has been largely overlooked. The use of PLS-SEM confirmed the hypothesized relationships, showing EO’s positive effects and EP’s partial mediation, while demonstrating the methodological suitability of this approach for complex, multidimensional sustainability outcomes. Future research should extend this framework to other regions and incorporate social performance dimensions to provide a more comprehensive view of sustainable SME performance.
Photovoltaic (PV) modules are vital components of renewable energy systems, yet their performance tends to decline over time due to exposure to various environmental conditions. In Malaysia's tropical climate, where high humidity, intense sunlight, and frequent rainfall prevail, identifying the key factors contributing to this degradation is crucial. This paper examines the primary degradation modes in four monocrystalline silicon PV modules after nine years of outdoor exposure in Kuala Lumpur, Malaysia, offering insights into real-world degradation mechanisms that can help manufacturers enhance durability and performance of solar energy systems in similar climates. The outcomes are compared with other studies that analyse the degradation of PV modules under similar tropical conditions with nearly identical exposure periods of 8, 11, and 12 years. The analysis was carried out using visual inspection, electroluminescence, and electrical performance evaluation to assess the extent of degradation. The findings indicated a substantial average power degradation of 40.35%. The most significant factors contributing to this severe power loss were encapsulant discolouration and the presence of snail trails with cracks. Notably, the extreme discolouration of the encapsulant documented in this research aligns with results from a Spanish study, in which PV modules underwent 22 years of exposure. This comparison highlights how humidity and temperature accelerate deterioration, making the findings relevant for other tropical regions. These results underscore the rapid deterioration of PV modules in tropical regions and provide crucial insights for improving PV system performance in high-humidity climates.
Asphalt concrete has always been the foundation for constructing resilient and durable road infrastructures. The enhanced performance of asphalt concrete in recent years has facilitated the development of high modulus asphalt concrete (HMAC). The primary objective of this review is to provide insight into the current advanced asphalt technology, including material composition, mix design, and mechanical performance parameters; compare the asphalt technologies adopted by different countries; and discuss the innovations, challenges, and prospects shaping the future of asphalt technology. Besides exploring innovative ways of utilizing environmentally friendly materials and pavement technologies, this paper analyzes climate change and the urgent need to reduce carbon footprints. It also discusses the prospects of utilizing HMAC, including the opportunities and challenges in various infrastructure applications. The literature review revealed that HMAC offers a promising approach to improving asphalt pavement performance, reducing the base layer thickness of asphalt, and reducing costs, energy consumption, and environmental impact. Several countries are enthusiastic about utilizing HMAC due to its exceptional durability and performance compared to conventional asphalt concretes. The future directions for HMAC are emerging technologies and sustainable practices. This review summarizes the insights from recent research, industry developments, and technological innovations to provide a comprehensive perspective on high-performance asphalt concrete. This continuously evolving field of road construction is a valuable resource for researchers, practitioners, and policymakers.
Silver–platinum (AgPt) binary nanoalloys were fabricated via a liquid-phase deposition strategy using formic acid (FA) with various concentrations. The synthesis resulted in a two-dimensional AgPt nanoferns structure with high crystallinity and uniform elemental distribution. X-ray photoelectron spectroscopy confirmed strong electronic interactions between Ag and Pt, indicating successful alloy formation. Electrochemical measurements revealed that the AgPt nanoferns exhibit outstanding multifunctional catalytic activity toward methylene blue degradation and water splitting. The catalyst prepared with 0.5 mM FA delivered the highest performance, achieving a turnover number of 3.2 × 103 within 5 min and a turnover frequency of 2.5 × 102 min⁻1, along with the lowest Tafel slope of 136 mV dec⁻1. The enhanced catalytic efficiency is primarily attributed to the synergistic Ag–Pt interaction and the unique nanoferns morphology, which provide abundant active sites and promote rapid charge transfer. This work demonstrates a rational strategy for designing an efficient bimetallic electrocatalyst for environmental remediation and sustainable energy conversion.
Botulinum toxin type A (BoNT-A) is an established preventive therapy for chronic migraines; however, uncertainty remains regarding its comparative efficacy and safety. Thus, we aimed to summarize current evidence from high-quality systematic reviews of the therapeutic effects of BoNT-A in migraine management. An umbrella review was conducted following PRISMA guidelines and registered in PROSPERO. High-quality systematic reviews with meta-analysis evaluating BoNT-A efficacy were identified through five databases up to August 2024. Primary outcomes included monthly headache frequency and severity. Methodological quality and risk of bias were assessed using the umbrella review checklist. Fourteen articles were included. Overall, quantitative evidence indicated favorable effects of BoNT-A compared with placebo for chronic migraines, across headache frequency, headache severity, and acute medication use, but less efficacy than topiramate and the CGRP monoclonal antibodies (CGRPmAbs) galcanezumab and fremanezumab. Though the adverse events were frequent, BoNT-A was generally well-tolerated. Comparative data suggested superior tolerability versus topiramate and a safety profile like CGRPmAbs. Although botulinum toxin type A is widely used as a preventive treatment for chronic migraines, the available evidence supports its efficacy at a moderate level. Further head-to-head and long-term analyses are needed to clarify its comparative role alongside newer biologic treatments.
