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Degradation of bisphenol A by Fe-doped BiOBr enhanced UV/persulfate system: Significant role of superoxide radicals
No full textWidely diffused pollution of endocrine disrupting chemicals (EDCs) has indeed threatened the safety of ecological environment and human health. A hydrangea-like Fe doped BiOBr (Fe-BiOBr) microsphere was synthesized and used to enhance the performance of UV/persulfate (PS) system using bisphenol A (BPA) as the targeted contaminant. The photochemical characterization of Fe-BiOBr showed that Fe doping markedly improved the separation efficiency of photoelectron and hole, and enhanced the utility rate of luminous energy of BiOBr. Degradation test demonstrated that with the assistance of Fe-BiOBr, the efficiency of UV/PS system was increased by 1.8 times, while 85.7% of BPA can be degraded within 10 min. Through scavenging experiments, sulfate radical (SO4•−), superoxide radical (O2•−), and hole were demonstrated as the dominate reactive species (RSs) in UV/Fe-BiOBr/PS system. Then, the role and mutual transformation of RSs was further clarified by radicals steady-state concentrations estimation and X-ray photoelectron spectroscopy (XPS) analysis. Based on the results, the produced O2•− can be subdivided into confined O2•− and free O2•− from the UV induced oxygen vacancy and photoelectron, respectively. Of which, SO4•− and confined O2•− were symbiotic via the redox cycle of Fe species. Significantly, only 2.6% of TOC can be simultaneously removed within 10 min treatment time, suggesting the incomplete degradation of BPA. For this, 16 organics was detected using LC-MS and the degradation route of BPA was also determined based on the intermediates analysis. Finally, the application possibility of the system was evaluated from the perspective of ecotoxicity by ECOSAR and T.E.S.T. softwares. This study investigates the dual effect of transition metal doped semiconductor on coupling system, and provides new insights into the role of O2•−
Novel hybrid evolutionary algorithm for bi-objective optimization problems
No full textThis work considers the Bi-objective Traveling Salesman Problem (BTSP), where two conflicting objectives, the travel time and monetary cost between cities, are minimized. Our purpose is to compute the trade-off solutions that fulfill the problem requirements. We introduce a novel three-Phase Hybrid Evolutionary Algorithm (3PHEA) based on the Lin–Kernighan Heuristic, an improved version of the Non-Dominated Sorting Genetic Algorithm, and Pareto Variable Neighborhood Search, a multi-objective version of VNS. We conduct a comparative study with three existing approaches dedicated to solving BTSP. To assess the performance of algorithms, we consider 20 BTSP instances from the literature of varying degrees of difficulty (e.g., euclidean, random, mixed, etc.) and different sizes ranging from 100 to 1000 cities. We also compute several multi-objective performance indicators, including running time, coverage, hypervolume, epsilon, generational distance, inverted generational distance, spread, and generalized spread. Experimental results and comparative analysis indicate that the proposed three-phase method 3PHEA is significantly superior to existing approaches covering up to 80% of the true Pareto fronts
Intellectual capital and firm performance: the moderating effect of auditor characteristics
No full textPurpose: This study aims to examine the impact of intellectual capital (IC) and its three components (human, structural and relational capital) on corporation performance in the Chinese transportation industry. In addition, this study also investigates auditor characteristics (both Big-N and non-Big-N auditors) as a moderating role to examine the relationship between IC and corporate performance. Design/methodology/approach: The data include 398 firm-year observations of transportation companies listed on the Shanghai and Shenzhen Stock Exchange from 2011 to 2020. Value-added intellectual coefficient (VAIC) model and its modified version (MVAIC) are applied to measure IC efficiency. Finally, the fixed effects regression analysis is used to mitigate the endogeneity issue. To investigate the moderating effect of auditor characteristics, the authors divide the samples based on the clients audited by Big-4 and non-Big-4 firms. Findings: This study reveals that IC can enhance firm performance in China’s transportation sector. Overall, findings indicate that on the whole, IC has a positive and significant impact on corporation profitability and productivity. Human capital and physical and financial assets (capital employed) play highly important roles, but structural capital has no significant impact. The authors also found that auditor characteristics play an important moderating role in the connection between IC and corporate performance. For example, the positive association between IC and corporate performance is more pronounced when Big-4 auditors audit client firms. At the same time, the authors found a negative relationship between IC and firm performance when non-Big-4 auditors audit client firms. Practical implications: Managers must understand that several components of IC have a total effect on corporate financial performance. Therefore, managers can dedicate more resources to such components based on the performance outcomes to emphasize their business strategies. Originality/value: This study is the first empirical analysis of the impact of IC and its components on corporation performance in the transportation sector in China, an emerging market. Previous studies mainly focus on developed countries’ high technology and financial industries sectors but the impact of IC in transportation industry largely remains unknown. Thus, the present findings contribute to IC literature by revealing several underlying mechanisms by which the components of IC help achieve good firm performance
Deep-sea fisheries as resilient bioeconomic systems for food and nutrition security and sustainable development
No full textThe frequent deterioration of coastal fisheries has resulted in a need to nourish the world\u27s rapidly expanding population, contributing to a substantial shift toward fishing in the mesopelagic zone. These areas contain a potentially huge amount of fish biomass. Considering that the global population will demand an increase of 60% in food production by 2050, it appears that exploiting the mesopelagic resources is simply a question of time. The present paper reviews the major risks and opportunities related to the exploitation of mesopelagic fisheries. Due to the significance of the uncertainties related to the stock of fish resources, environmental and biodiversity effects of the deep-sea fisheries, this inquiry advocates for the enhancement of sustainable small-sized deep-sea fishery practices on the one hand side and a global moratorium on large-scale mesopelagic fishing on the other hand. Deep seas could provide substantial resources for combating global food insecurity and facilitate a substantial improvement of the nutritional status in the regions plagued by a high incidence of infant mortality and disproportional poverty headcount ratios. For the sake of global and regional food and nutrition security, the exploitation of the biological resources of the mesopelagic zone is a legitimate target, whereby environmental sustainability is the major precondition for the rollout of these kinds of fishing activities
Buy green only: Interplay between green marketing, corporate social responsibility and green purchase intention; the mediating role of green brand image
No full textConsumers around the globe are concerned about the environment and want to purchase from businesses that are more concerned about society and the environment. Therefore, businesses need to develop their image as socially responsible entities and build their green image through green marketing tactics to enhance the green purchase intentions of their consumers. The study is quantitative, and a convenience sampling technique is used to collect primary data through a self-administered questionnaire comprised of the demographic profile of the respondents and adopted scales of all the constructs of the study. The population of the study is students of different universities in the Punjab province of Pakistan. Statistical tests are performed with the help of SPSS_v.20 and PLS_v.4 (variance based) on 782 useable responses. Green marketing (GM) and corporate social responsibility (CSR) are the independent variables, while green brand image (GBI) is mediating, and green purchase intention (GPI) is the dependent variable of the study. The results indicate that GM and CSR improved the GBI and built GPI. This study contributes to the social and environmental literature. It may help managers to formulate strategies to enhance the Green Purchase Intentions of customers by building a Green Brand Image
The Roles of Coenzyme A Binding Pocket Residues in Short and Medium Chain Acyl-CoA Synthetases
No full textShort- and medium-chain acyl-CoA synthetases catalyze similar two-step reactions in which acyl substrate and ATP bind to form an enzyme-bound acyl-adenylate, then CoA binds for formation of the acyl-CoA product. We investigated the roles of active site residues in CoA binding in acetyl-CoA synthetase (Acs) and a medium-chain acyl-CoA synthetase (Macs) that uses 2-methylbutyryl-CoA. Three highly conserved residues, Arg193, Arg528, and Arg586 of Methanothermobacter thermautotrophicus Acs (AcsMt), are predicted to form important interactions with the 5′- and 3′-phosphate groups of CoA. Kinetic characterization of AcsMt variants altered at each of these positions indicates these Arg residues play a critical role in CoA binding and catalysis. The predicted CoA binding site of Methanosarcina acetivorans Macs (MacsMa) is structurally more closely related to that of 4-chlorobenzoate:coenzyme A ligase (CBAL) than Acs. Alteration of MacsMa residues Tyr460, Arg490, Tyr525, and Tyr527, which correspond to CoA binding pocket residues in CBAL, strongly affected CoA binding and catalysis without substantially affecting acyl-adenylate formation. Both enzymes discriminate between 3′-dephospho-CoA and CoA, indicating interaction between the enzyme and the 3′-phosphate group is important. Alteration of MacsMa residues Lys461 and Lys519, located at positions equivalent to AcsMt Arg528 and Arg586, respectively, had only a moderate effect on CoA binding and catalysis. Overall, our results indicate the active site architecture in AcsMt and MacsMa differs even though these enzymes catalyze mechanistically similar reactions. The significance of this study is that we have delineated the active site architecture with respect to CoA binding and catalysis in this important enzyme superfamily
Proposing and Empirically Investigating a Mobile-Based Outpatient Healthcare Service Delivery Framework Using Stimulus-Organism-Response Theory
No full textThe emergency departments (EDs) of tertiary hospitals (THs) are significantly overcrowded, while primary healthcare centers (PHCCs) are underutilized. Therefore, the Chinese government is attempting to reduce outpatient flow from THs and establish a referral system between the EDs of THs and PHCCs. First, in this article, we propose a mobile-based outpatient healthcare service delivery framework (MOHSDF), which can help divert the flow of outpatients toward the PHCCs before they visit the EDs of THs. Second, this article examines that the MOHSDF-specific characteristics, including performance attributes (e.g., effort expectancy and performance expectancy), communicative power (e.g., interactivity), and perceived government support, are the stimuli that can help build an organism (e.g., initial trust and internal satisfaction). This organism will result in the behavioral intent to prescribe treatment using the MOHSDF. The data are collected from 292 TH physicians in Hefei, China, and analyze using Smart-PLS. All the proposed hypotheses are accepted, excluding two direct and one mediating relationship. These insignificant direct relationships are between performance attributes and internal satisfaction. Moreover, internal satisfaction does not mediate the relationship between effort expectancy and behavioral intent to prescribe treatment using the MOHSDF. This article has significant implications for researchers, government healthcare authorities, policymakers, and m-health service providers
Discovery of facultative parthenogenesis in a new world crocodile
No full textOver the past two decades, there has been an astounding growth in the documentation of vertebrate facultative parthenogenesis (FP). This unusual reproductive mode has been documented in birds, non-avian reptiles - specifically lizards and snakes - and elasmobranch fishes. Part of this growth among vertebrate taxa is attributable to awareness of the phenomenon itself and advances in molecular genetics/genomics and bioinformatics, and as such our understanding has developed considerably. Nonetheless, questions remain as to its occurrence outside of these vertebrate lineages, most notably in Chelonia (turtles) and Crocodylia (crocodiles, alligators and gharials). The latter group is particularly interesting because unlike all previously documented cases of FP in vertebrates, crocodilians lack sex chromosomes and sex determination is controlled by temperature. Here, using whole-genome sequencing data, we provide, to our knowledge, the first evidence of FP in a crocodilian, the American crocodile, Crocodylus acutus. The data support terminal fusion automixis as the reproductive mechanism; a finding which suggests a common evolutionary origin of FP across reptiles, crocodilians and birds. With FP now documented in the two main branches of extant archosaurs, this discovery offers tantalizing insights into the possible reproductive capabilities of the extinct archosaurian relatives of crocodilians and birds, notably members of Pterosauria and Dinosauria
Harnessing the Potential of Non-Apoptotic Cell Death Processes in the Treatment of Drug-Resistant Melanoma
No full textMelanoma is a highly malignant skin cancer that is known for its resistance to treatments. In recent years, there has been significant progress in the study of non-apoptotic cell death, such as pyroptosis, ferroptosis, necroptosis, and cuproptosis. This review provides an overview of the mechanisms and signaling pathways involved in non-apoptotic cell death in melanoma. This article explores the interplay between various forms of cell death, including pyroptosis, necroptosis, ferroptosis, and cuproptosis, as well as apoptosis and autophagy. Importantly, we discuss how these non-apoptotic cell deaths could be targeted as a promising therapeutic strategy for the treatment of drug-resistant melanoma. This review provides a comprehensive overview of non-apoptotic processes and gathers recent experimental evidence that will guide future research and eventually the creation of treatment strategies to combat drug resistance in melanoma