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Enhancing stochastic optimization: investigating fixed points of chaotic maps for global optimization
Chaotic maps, despite their deterministic nature, can introduce controlled randomness into optimization algorithms. This chaotic map behaviour helps overcome the lack of mathematical validation in traditional stochastic methods. The chaotic optimization algorithm (COA) uses chaotic maps that help it achieve faster convergence and escape local optima. The effective use of these maps to find the global optimum would be possible only with a complete understanding of them, especially their fixed points. In chaotic maps, fixed points repeat indefinitely, disrupting the map's characteristic unpredictability. While using chaotic maps for global optimization, it is crucial to avoid starting the search at fixed points and implement corrective measures if they arise in between the sequence. This paper outlines strategies for addressing fixed points and provides a numerical evaluation (using Newton's method) of the fixed points for 20 widely used chaotic maps. By appropriately handling fixed points, researchers and practitioners across diverse fields can avoid costly failures, improve accuracy, and enhance the reliability of their systems. 2024 Institute of Advanced Engineering and Science. All rights reserved. -
The accumulation, antioxidant defences, and secondary metabolite production in common sage (Salvia officinalis L.) under lead toxicity
The growing levels of lead (Pb) in agricultural soil and water bodies as a result of industrialization and human activity present serious challenges for medicinal plants. The present study investigates the complex responses of Salvia officinalis to toxicity caused by Pb including metal accumulation, translocation dynamics, antioxidant defenses, and the production of secondary metabolites. Pb showed preferential accumulation in the roots, peaking at (1000 ppm Pb) (2484.2 mg kg-1). The reduced levels of total chlorophyll (1.29-fold), protein (1.9-fold), and carbohydrate (2.5-fold) under prolonged exposure to stress demonstrate the toxic impacts of lead. Proline and total phenolic content (TPC) increased concentration-dependently under lead stress, while flavonoids were found to be decreased with the enhancement of lead toxicity. Enzymatic antioxidants (catalase, APX, and SOD) showed notable increase, especially in the 30 days of treatment, demonstrating the plants strong defenses. S. officinaliss adaptive responses were highlighted by concentration-dependent increases in non-enzymatic antioxidants such as total antioxidant capacity (TAC) and DPPH radical scavenging activity. Crucially, under lead stress, S. officinalis showed 1.7-fold increased rosmarinic acid (RA) production, in plants exposed to 200 ppm for 30 days treatment. However, further exposure to lead significantly caused the reduction of RA production. The results add to our knowledge of how sage plants respond to environmental stress and offer important insights for future uses in phytoremediation and the breeding of stress-tolerant plant cultivars. Furthermore, the research highlights about the S. officinaliss potential as a source of bioactive compounds possessing antioxidant qualities, under low levels of lead stress. 2024, Indian journals. All rights reserved. -
Structural modification of electrophilic group substituted phenyldiazenyl derivatives for antitubercular application
In the present work, four electrophilic group substitute phenyldiazenyl derivatives were synthesized using an electrophilic substitution reaction. The physicochemical analysis was carried out using FT-IR, 1H NMR, and HR-MS data. The photophysical studies were carried out using theoretical methods. Density functional theory was employed to illustrate the electronic and optical characteristics of the synthesized compounds. The HOMO-LUMO energies were theoretically computed in different solvents using Gaussian 09W software and results are compared with the experimental values. The molecule PT4 shows highest bandgap of 4.497eV. Further, the global chemical reactivity descriptors were used to determined nature of chemical reactivity. The anti-tubercular activity was evaluated using invitro and molecular docking techniques and results reveal that barbituric acid coupled with phenyldiazenyl displayed excellent anti-tubercular activity compared with the standard Gentamycin. 2024 Indian Chemical Society -
Bed shear stress distribution across a meander path
Laboratory experimentation for bed shear stress distribution has been carried out in two sets of meandering channels. The channels have crossover angles of 110 and 60 constructed by sine-generated curves over a flume of 4 m width. Variations in bed roughness were studied for the meandering main channel. Bed shear stress distribution across a meandering length for the 110 and 60 channels was examined for different sinuosities and roughnesses. The boundary shear stress study illustrated the position of maximum shear along the apex section and across the meandering path. These variations were observed for different flow depths. A comparison of the bed shear among the three experimental channels was conducted, and the results were analyzed. 2024, IWA Publishing. All rights reserved. -
Structural investigation of Cr2CTx/NiFe2O4 MXene composite as a bifunctional electrocatalyst for water splitting
The electrocatalytic water splitting offers great potential as an environmentally friendly and sustainable method to produce hydrogen and oxygen, the former serving as a renewable alternative to traditional fossil fuels. MXene, a novel two-dimensional (2D) layered class of materials, has gained enormous attention as an electrocatalyst for water splitting. This versatile material can be tailored to enhance its electroactive surface sites and stability toward electrocatalytic performance. Herein, we have designed a 2D hybrid material, Cr2CTx/NiFe2O4, via an in-situ hydrothermal approach. NiFe2O4 spheres decorated on layered-Cr2CTx are subjected to analysis using XRD, FTIR, TGA, XPS, FESEM, HRTEM-SAED, and optical profilometry. The synthesized hybrid MXene material shows outstanding activity for overall water splitting compared to Cr2CTx and NiFe2O4. Cr2CTx/NiFe2O4 exhibits an overpotential of 144 mV and 159 mV at a current density of 10 mA cm?2 for hydrogen evolution and oxygen evolution reactions, respectively, and achieves a cell potential of 1.69 V for overall water splitting. This study reveals valuable insights on bi-functional 2D hybrid MXene materials for electrocatalytic water splitting. 2024 Elsevier B.V. -
Cloud databases: A resilient and robust framework to dissolve vendor lock-in
Vendor lock-in has become a major concern in cloud computing. The term vendor lock-in describes situations where the subscriber cannot move data or services to another cloud vendor. This is due to heavy data volumes, high network bandwidth costs, dependencies, or unacceptable downtime. The proposed vendor lock-in dissolution practice migrates the database effectively in noticeably less time, regardless of database size and with a nominal network bandwidth requirement. Through this new practice, databases can be migrated to very remote regions, even across continents. A real-time implementation of the proposed method presented in this paper. 2024 The Author(s) -
MATHEMATICAL MODEL OF NICKEL-GRAPHENE COMPOSITE INKS FOR JETTING PROPERTIES IN INKJET PRINTING
The droplet formation process in inkjet printing is studied numerically and verified through a simulation model. The droplet formation process decides the printing quality of the coating, and a mathematical model is developed to understand the complete process from droplet formation to detachment. The Navier-Stokes equation is used to mathematically derive the droplet radius (rnumerical). COMSOL multiphysics is used for simulation and the radius (rsimulation) is calculated from the droplet mass. The rnumerical and rsimulation are compared for inks containing nickel, graphene, and nickel-graphene composite ink it is observed that the composite ink radiuses have the lowest difference (rsimulation - rnumerical = 0.085 m). A droplet is formed at 1.47 mm from the nozzle inlet, for nickel-graphene ink, and after 1.5mm for other pristine inks. The results are verified through Z number, velocity profile, and droplet mass. The droplet formation observed from the velocity profile is earliest at 120 s. It is seen that a stable droplet is generated at 100s for nickel-graphene ink and at 200 s for individual inks. 2024 Faculty of Science, Universiti Malaya. All rights reserved. -
En route to Khardung La with Dhak Dhak
Dhak Dhak uses the trope of a motorcycle road trip to discuss several societal and emotional barriers women ought to overcome to forge their own paths and blossom into their authentic selves. 2024 Economic and Political Weekly. All rights reserved. -
Chernobyl Disaster Optimizer-Based Optimal Integration of Hybrid Photovoltaic Systems and Network Reconfiguration for Reliable and Quality Power Supply to Nuclear Research Reactors
In view of the complexity and importance of nuclear research reactor (NRR) installations, it is imperative to uphold high standards of reliability and quality in the electricity being supplied to them. In this paper, the performance of low-voltage (LV) distribution feeders integrated with NRRs is improved in terms of reduced distribution loss, improved voltage profile, and reduced greenhouse gas (GHG) emissions by determining the optimal location and size of photovoltaic (PV) systems. In the second stage, the power quality of the feeder is optimized by reducing the total harmonic distortion (THD) by optimally allocating D-STATCOM units. In the third and fourth stages, the reliability and resilience aspects of the feeder are optimized using optimal network reconfiguration (ONR) and by integrating an energy storage system (ESS). To solve the non-linear complex optimization problems at all these stages, an efficient meta-heuristic Chernobyl disaster optimizer (CDO) is proposed. Simulations are performed on a modified IEEE 33-bus feeder considering the non-linear characteristics of NRRs, variability of the feeder loading profile, and PV variability. The study reveals that the proposed methodology can significantly improve the service requirements of NRRs for attaining sustainable research activities. 2024 by the authors. -
Purification and evaluating in vitro activity of a fibrinolytic protease produced by a mangrove isolate Bacillus subtilis AIBL_AMSB2_M7E32
One of the main causes of heart-related problems globally is intravascular thrombosis. Microbial fibrinolytic proteases play a very crucial role in the management of thrombosis. Plasminogen activators and plasmin-like proteins, which are fibrinolytic enzymes of microbial origin, hydrolyze thrombin with great efficacy and without causing noticeable side effects. These fibrinolytic enzymes can also be manufactured efficiently and economically in huge quantities within a short period. However, the search for novel fibrinolytic enzymes demands difficult purification procedures, as well as physicochemical and structural-functional properties that provide information about their mode of action. In this study, the strain named Bacillus subtilis AIBL_AMSB2_M7E32, isolated from the Coringa mangrove soils, was shown to produce a fibrinolytic enzyme. The enzyme was purified by a four-step purification process that resulted in a 43.33-fold purification with a specific activity of 6368.20 (U/mg). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that the purified enzyme was a protein of about 28 kDa and showed fibrinolytic activity on a zymogram. In vitro assay on blood clots revealed that the purified enzyme could lyse the blood effectively by a percentage of 72.96 0.16a%, indicating that the enzyme could be used as a fibrinolytic agent. Furthermore, an observation for enzyme stability and its in vivo activity studies would be necessary for its application in the market. 2024 Bhavana Sompalli and Alok Malaviya. -
Analyzing the therapeutic significance of Strelitzia reginae Banks: Exploring its physico-chemical properties, elemental makeup, and antimicrobial activity
Plants constituting biologically active molecules with curative value have overtime showed advantage as subject of researches. Strelitzia reginae (Bird of Paradise) is a member of the Strelitziaceae family. Several South African tribes used plant parts to treat the venereal diseases and inflamed glands. The study aimed to investigate therapeutic potential of leaf and root extracts of S. reginae by assessing the physico-chemical properties, elemental analysis. Elemental analysis was carried out by Atomic Absorption Spectrometry (AAS) method, quantitative phytochemical analysis was carried out using, Gas Chromatography and Mass Spectrometry (GC-MS) analysis. The leaf and root of S. reginae were extracted using soxhlet technique of extraction and was further concentrated with a rotary evaporator. Standard protocols assessed the plants elemental compounds, physico-chemical properties, qualitative and quantitative phytochemicals, GC-MS analysis, antioxidant activity using DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging assay, phosphomolybdate assay, ferric reducing power assay (FRAP), metal chelating assay, and antimicrobial potential by well diffusion test. The results of AAS exhibited that the leaf and root contain more calcium and less of cadmium content. Preliminary phytoconstituents showed the presence of medicinally important alkaloids, anthraquinones, tannins, carbohydrates, flavonoids, saponins, phenols, proteins, and amino acids. The quantitative phytochemical analysis revealed that the leaf has higher total phenolic, flavonoid, chlorophyll, carbohydrates, protein, and proline contents than root. GC-MS analysis verifies the existence of bioactive components like squalene, hexatriacontane, phytol, hexacosane, heptacosane, and octacosane. DPPH, phosphomolybdate assay, FRAP and metal chelating antioxidant analysis revealed excellent activity in leaf and in root sample. As various South African tribes employed plant parts to treat sexual diseases and swollen glands, the antimicrobial property was investigated for the first time using a well-diffusion approach, and both plant parts revealed significant antibacterial and antifungal efficacy against recognized strains. The current study showed S. reginaes therapeutic potential and asked for more pharmacological and biological research to boost the importance of the worlds unevaluated herbal plants. 2024, Indian journals. All rights reserved. -
Electrospun nanofibers of 2D Cr2CTx MXene embedded in PVA for efficient electrocatalytic water splitting
The usage of transition metal carbide-based electrocatalysts has proven to be an efficient and effective strategy for enhancing the kinetics of water splitting reactions encompassing the generation of hydrogen (hydrogen evolution reaction, HER) and oxygen (oxygen evolution reaction, OER). In this investigation, we have prepared a composite material by integrating Cr2CTx MXene (derived from Cr2AlC MAX phase) and polyvinyl alcohol (PVA) through electrospinning technique. Carbonization of the MXene-PVA nanofibers resulted in the formation of Cr2CTx/carbon nanofiber (Cr2CTx/CNF) that exhibits high porosity, stability, surface area, and electrocatalytic activity. Systematic examination and optimization for the electrocatalytic water splitting reaction reveales outstanding performance, characterized by substantially lower overpotentials of 265 mV and 250 mV at the constant current density of 10 mA cm?2 with lower Tafel slope values of 85 mV dec?1 and 52 mV dec?1 for HER and OER, respectively. Moreover, this work presents a novel strategy for fabricating non-precious electrocatalyst Cr2CTx/CNF through a cost-effective and straightforward electrospinning and carbonization process, advancing electrocatalytic water splitting applications, especially for oxygen evolution reactions. 2024 The Royal Society of Chemistry. -
Sustainable human resource management and job satisfactionUnlocking the power of organizational identification: A cross-cultural perspective from 54 countries
Sustainable human resource management is gaining importance in organizations due to its role in developing a sustainable work environment and well-being. This paper discusses the relationship between employee perceptions of sustainable human resource management and job satisfaction in 54 countries. We propose that sustainable HRM is positively associated with job satisfaction but that this relationship is moderated by employees' identification with the organization and country-level individualismcollectivism. Thus, we suggest national culture functions as a second-level moderator of the relationship of sustainable HRM with organizational identification on job satisfaction. Findings from the multi-level analyses using data from 14,502 employees nested within 54 countries provided support for our hypotheses, namely that employee perceptions of sustainable HRM were positively associated with job satisfaction and that this relationship was more pronounced for employees with lower levels compared to higher levels of organizational identification in individualistic rather than collectivistic countries. These findings bear important implications for both theory and practice. 2024 ERP Environment and John Wiley & Sons Ltd. -
New results on orthogonal component graphs of vector spaces over Zp
A new concept known as the orthogonal component graph associated with a finite-dimensional vector space over a finite field has been recently added as another class of algebraic graphs. In these types of graphs, the vertices will be all the possible non-zero linear combinations of orthogonal basis vectors, and any two vertices will be adjacent if the corresponding vectors are orthogonal. In this paper, we discuss the various colorings and structural properties of orthogonal component graphs. 2024 Azarbaijan Shahid Madani University. -
Do economic globalization and the level of education impede poverty levels? A non-linear ARDL approach
This study empirically examines whether economic globalization reduces (enhances) the level of poverty in the top (bottom) globalized region by controlling economic growth, urbanization, government expenditure, and public expenditure on education. This issue has taken Europe and Central Asia (ECA) as the top (16) and South Asia (SA) as the bottom (7) economic globalized developing region for the empirical analysis for the period of 1991-2020. Two empirical models, non-linear ARDL and PMG-ARDL, estimate the impact of globalization (trade and financial openness) and education on poverty. This study also segregates economic globalization into de jure and de facto to critically analyze the impact on poverty reduction. The long-run results suggest that economic globalization has a negative (positive) effect on poverty in the top (bottom) globalized region. Apart from globalization, primary education is insufficient for reducing poverty in the ECA region, while primary education is enough to reduce poverty in the SA region. After replacing economic globalization with trade and financial openness, the results reveal that more trade openness is difficult for reducing poverty in top globalized developing countries. On the contrary, financial openness reduces (enhances) poverty in the top (bottom) globalized region. Additionally, the impact of de jure and de facto economic globalization are similar throughout the regions. The effects of control variables are mixed in nature. From a policy perspective, the government of these two regions should use education as a weapon to lower poverty vulnerability by improving its quality and giving extensive focus on trade and financial openness to find out the leakage of the financial flows. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024. -
Streamlined electrochemical harvesting of cobalt and nickel from soft cemented carbide scrap for superior supercapacitors
We propose a complete circular economy and sustainability model from soft cemented carbide scrap to supercapacitor application. An enhanced recovery of cobalt and nickel was observed when deep eutectic solvent was used. A comparative in-situ electrochemical deposition of the recovered metals was done on stainless steel (SS), SS/activated carbon (AC), and SS/AC/polyaniline (PANI). The optimization of electrochemical extraction was carried out by varying voltage, time, and temperature. The surface area and conductive polymer's electronic distribution contributed to different surface morphological deposition of specific metals on them. Unique fluffy particle deposition was observed on the surface as fine grain particles with uniform particle size within 1 m. The fabricated supercapacitors showed the pseudocapacitance behaviour. The presence of metal oxide nanocomposite deposition as the active material is particularly pronounced in the SS/AC/PANI device due to the inclusion of PANI as an active material and its substantial contribution to pseudocapacitance. The higher charge-discharge time of SS/AC/PANI at the same current densities compared to SS/AC may be due to the above-mentioned additional contribution of PANI's quickly reversible redox behavior. Hence, the overall electrochemical extraction from scrap to supercapacitor will undoubtedly lead to achieving the sustainable development goals (SDGs) 2024 -
SECURE EQUITABLE SUBDIVISION NUMBER OF GRAPHS
In this paper, we initiate the study of a new domination parameter: the secure equitable subdivision number of graphs. Moreover, we define the secure equitable subdivision critical graphs and the secure equitable subdivision stable graphs. Furthermore, we investigate how to construct a secure equitable subdivision critical graph. 2024, Canadian University of Dubai. All rights reserved. -
The Role of Perceived Organisational Support in Predicting Organisational Commitment and Organizational Citizenship Behavior in Professional Organizations
The study examined the "role of perceived organisational support in predicting organisational commitment and organisational citizenship behaviour in professional organisations". The primary data was acquired through a questionnaire from 200 respondents (employees from the finance and technology sectors) via a stratified random sampling technique. Excel and SPSS 26 were utilised for data analysis, and Statistical tools such as Anova, regression and correlation were used. The results demonstrated that perceived organisational support (POS) positively influences organisational commitment. Moreover, it has been found that perceived organisational support (POS) and organisational citizenship behaviour (OCB) in professional organisations have a substantial correlation, and there are significant differences in the perception of organisational support, commitment, and OCB among professionals working in the technology and finance sectors. This study can assist decision-makers and managers in the finance and technology sector in creating a comprehensive plan for organisational support and development programs that effectively include employees in their job responsibilities. The study provides valuable insights into the importance of perceived organisational support in fostering organisational commitment and citizenship behaviour. 2024, Creative Publishing House. All rights reserved. -
Calcination process of porous metalorganic frameworks derived from nickel sulfide composites for supercapacitor and computer vision for investigating the porosity-electrochemical correlation
The utilization of metalorganic framework nanostructured electrode materials in supercapacitors and sensor applications is achieved by various chemical methods. In this study, we create NiS and NiS@MOF-BDC by employing nickel precursors and benzene dicarboxylic acid (BDC) as chelating organic linkers through a thermal reduction procedure at a temperature of 400 C to produce the composite. The composite heterostructure enhanced the conductivity, porous characteristics, and diverse potential morphological qualities. The production of composite electrodes demonstrates a specific capacity of 260F/g (104C/g) when subjected to a current density of 1A/g. Additionally, these electrodes exhibit exceptional cyclic stability, enduring 5000 cycles, when used with a 2 M KOH electrolyte. Moreover, the synthesized composite HR-TEM images were analyzed using computer vision and AI techniques for estimating the porosity and investigating the enhanced electrochemical correlation. 2024 Elsevier B.V. -
ZnO nanorods on POPD/GCN/TCFP with ternary synergy for promoting electro-oxidation of furfuryl alcohol
In this work, Poly(o-phenylenediamine) (POPD) and zinc oxide (ZnO) nanoparticles were electrochemically deposited on GCN (graphitic carbon nitride) coated TCFP (Toray carbon fiber paper) electrode. The modified electrode ZnO-POPD-GCN-TCFP was assessed by Field emission scanning electron microscopy (FESEM), X-ray diffraction analysis (XRD), and X-ray photoelectron spectroscopy (XPS) studies. The electrochemical studies were carried out via cyclic voltammetry (CV) and electrochemical impedance spectroscopic (EIS) methods. The developed electrode was employed for the oxidation of furfuryl alcohol (FA) using 4-ACT (4-acetamido TEMPO) as a mediator in an alkaline medium via bulk electrolysis. Proton nuclear magnetic resonance (1H NMR) spectroscopy was used to characterize the final product. The oxidation of FA to furfural was accelerated by the heterogeneous catalyst ZnO-POPD-GCN-TCFP electrode owing to its good electrocatalytic activity and stability. Hence, a sustainable electrochemical method for synthesizing furfural, with significance in the realm of green chemistry, was developed. The Electro-oxidation of FA offers a clean alternative to traditional methods utilizing electricity, potentially from renewable sources, to drive the reaction, reducing reliance on harsh chemicals and minimizing environmental impact. By adjusting parameters like electrode potential and electrolyte composition, it is possible to optimize the reaction conditions for furfural production with optimal yield, which has several applications in daily life. 2024 Elsevier Ltd