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Synthesis of Nanoflowers using Garcinia gummi-gutta Leaf Extract via Green Route for Enhanced Antifungal and Anti-cancerous Activities
Due to its envisaged relevance in nanomedicine and materials research, the bio-engineering of nanoparticles (NPs) is becoming progressively more promising. Compared to physical and chemical processes, green synthesis produces NPs that are less hazardous to the environment. The usage of phytochemicals in Garcinia gummigutta (L.) leaf extract (GGL) in the bio-reduction of GGL-Ag NPs with potential antifungal and anti-cancerous activities was the main focus of the current study. UV-vis spectrophotometry at 442 nm verified the synthesized GGL-Ag NPs. The average diameters of the synthesized GGL-Ag NPs were determined by scanning electron microscopy (SEM and zeta-sizer studies to be 166.69 nm and 148.2 nm, respectively. Energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD) examinations of the GGL-Ag NPs confirmed the crystalline nature and the elemental constitution of the NPs. Additionally, the synthesized GGL-Ag NPs' FTIR spectra demonstrated the presence of Phyto components acting as capping agents. Zeta potential measurements (-26.2 4.13 mV) authenticated the stability of the synthesized GGL-Ag NPs. Antimicrobial activity testing of the GGL-Ag NPs demonstrated considerable suppression against Candida tropicalis and Candida albicans at a dose of 100 g/ml and 60 g/ml. Additionally, the synthesized GGL-Ag NPs have demonstrated considerable cytotoxic effects on the Hep-G2 cell line. The current study results show that GGL-Ag NPs may be produced at a low cost and with minimal environmental impact for nanobiotechnology and biomedicine usage. 2024, Brawijaya University. All rights reserved. -
Optical design studies for national large optical-IR telescope
A 1012 m class national large optical-IR telescope (NLOT) is envisaged to meet the growing scientific requirements in astronomy and astrophysics. Telescopes of such dimensions can only be made by segmenting the primary mirror, as it eases a more prominent primary mirrors fabrication, transportation, operation, and maintenance process. This paper presents the various optical designs analyzed for NLOT that can be fabricated using the India TMT Optics Fabrication Facility (ITOFF) at the Centre for Research and Education in Science and Technology (CREST) campus. We present the primary mirror segmentation details, its ideal optical performance, and study each designs advantages and technical complexities. Based on the above analysis, we have narrowed it down to an optimal design, and its performance analysis is also discussed. Indian Academy of Sciences 2024. -
Synergistic fabrication, characterization, and prospective optoelectronic applications of DES grafted activated charcoal dispersed PVA films
This study investigates the synthesis, analysis, and utility of films comprising deep eutectic solvent (DES) grafted activated charcoal (AC) within a polyvinyl alcohol (PVA) matrix for optoelectronic device applications. The fabrication process involves the dispersion of DES functionalization AC into the PVA solution, followed by casting onto substrates with controlled drying. Comprehensive characterization encompassing X-ray diffraction (XRD), scanning electron microscopy (SEM), UVvis spectroscopy, Fourier-transform infrared spectroscopy (FTIR), and impedance spectroscopy which discerns the films microstructure, morphology, conductance, band-gap, and optical traits. The DES grafted AC infusion with variable concentration has significantly influenced optical absorbance and reduced the band gap indicating efficient charge mobility. Furthermore, the impedance analysis has revealed the electrical conduction of the film to be 1.8 10?6 ??1 m?1. In summary, the dispersion of DES modified AC in the PVA matrix have converted the insulating PVA to a semiconducting polymeric film with reduced band-gap and increased absorption, which present a propitious avenue for wide array of optoelectronic devices, such as thin film transistors, photovoltaics, LEDs, photodetectors, and many such applications. 2024 The Authors. Polymers for Advanced Technologies published by John Wiley & Sons Ltd. -
Defiance in the Shadows: Flames of Resilience in the Selected North Korean Memoirs
The resilient autobiography focuses on the interpersonal dynamics of life narratives, including the relationships that have exacerbated the hardships described and the ones that have provided the support and strength necessary to overcome them. The selected text for this paper is A Thousand Miles to Freedom: My Escape from North Korea by Eunsun Kim and Sebastien Falletti and In Order to Live: A North Korean Girls Journey to Freedom by Yeonmi Park and Maryanne Vollers. These two texts talk about their catastrophic journey from North Korea because of poverty caused by famine and their migration to China, where they were trafficked and subjected to humiliation and their final escape to South Korea. The memoirs depict the individual?s embodiment of resilience as they narrate their own struggles and victories in overcoming hardship. Resistance to adversity and suffering, as well as the ability to bounce back from painful experiences in one?s own life and in the lives of others, are the hallmarks of resilience. Trauma becomes ingrained in attempts for survival in both memoirs, which illustrate the catastrophic impacts of famine, relocation, and personal loss. One effective approach to enhance resilience is reorganizing and reestablishing control over one's life after a traumatic event. Interpretations and writings of the personal narrative are offered from both the subject?s and an outsider?s points of view. Thus, the life story is formed in a dual sense: autobiographically and biographically. 2024 Sciedu Press. All rights reserved. -
Investigating the dynamics, synchronization and control of chaos within a transformed fractional SamardzijaGreller framework
In this article, in response to the limitations of existing ecological models, we address the critical need for a more comprehensive understanding of predatorprey dynamics by presenting a modified fractional SamardzijaGreller model that incorporates intra- and inter-species competitions within two predator populations. Our model stands out for being more realistic because it considers the natural competition that occurs among and between two predator species when they share a common prey We derived the local stability conditions at equilibrium points using RouthHurwitz conditions for the modified model. With the help of a suitably chosen Lyapunov function, we also obtained the global stability condition for our fractional model. The existence of chaos has been confirmed through Lyapunov exponents and bifurcation in the new system for two distinct sets of initial conditions for different fractional orders. Employing the active control method, we establish conditions for synchronization between these two fractional systems and introduce control functions for chaos management in the modified model. Numerical simulations, utilizing the generalized AdamsBashforthMoulton method, support the theoretical findings across a spectrum of fractional orders ranging from 0 to 1. We demonstrated the adaptability of the active control method for different fractional orders. A fractional order of ? equal to 1 for synchronization shows rapid convergence, but a drop to ? equal to 0.80 causes a substantial slowdown that takes almost six times more number of iterations to complete. Thus, we shed light on how the fractional order of the system plays a pivotal role in determining the speed of synchronization, with lower orders leading to a noticeable delay and higher fractional orders favoring faster synchronization. Our thorough investigation contributes to the understanding of complex ecological systems and offers practical insights into fractional chaos control mechanisms within the context of predatorprey models. 2024 Elsevier Ltd -
Enhancing rainwater harvesting and groundwater recharge efficiency with multi-dimensional LSTM and clonal selection algorithm
Rainwater harvesting stands out as a promising solution to alleviate water scarcity and alleviate pressure on conventional water reservoirs. This work introduces a pioneering strategy to elevate the efficiency of rainwater harvesting systems through the fusion of Multi-Dimensional Long Short-Term Memory (LSTM) networks and the Clonal Selection Algorithm (CSA). The Multi-Dimensional LSTM networks serve to model intricate temporal and spatial rainfall patterns, enabling precise predictions regarding the optimal times and locations for rainwater abundance. This insight is pivotal in refining the design and operation of rainwater harvesting setups. Drawing inspiration from the immune system, the Clonal Selection Algorithm is employed to optimize site selection and resource allocation, ensuring the maximal utilization of harvested rainwater. The adaptability and robustness of CSA prove invaluable in tackling the dynamic nature of rainfall patterns. This research endeavor is dedicated to enhancing groundwater levels and optimizing its sources through the implementation of efficient harvesting techniques. By delving into innovative methodologies, it aims to contribute significantly to sustainable water management practices and ensure a reliable supply of groundwater for various societal needs. The experiments are conducted to study the effectiveness of rainwater harvesting systems, where the proposed method achieves increased efficiency, thereby reducing dependence on conventional water sources and contributing to sustainable water management practices. The proposed CSA-LSTM model demonstrates superior performance compared to ACO-ANN and PSO-BPNN, achieving higher training, testing, and validation accuracies while exhibiting lower training, testing, and validation losses. Additionally, CSA-LSTM showcases excellent site suitability, high resource utilization, and robustness to changes, with a fast response time, emphasizing its potential for efficient and effective applications. 2024 Elsevier B.V. -
Boosting productive capacity in OECD countries: Unveiling the roles of geopolitical risk and globalization
This study examines the intertwined effects of geopolitical risk and globalization on productive capacity (the measure of economic cycles) in 20 Organisation for Economic Cooperation and Development (OECD) countries from 2000 to 2021. The panel threshold regression and Driscoll-Kraay standard error estimations highlight the positive impact of globalization on productive capacity. Still, they are underscored by the negative effect of geopolitical risk. The study also unveils a synergistic relationship, demonstrating that the combined influence of globalization and geopolitical risk can amplify productive capacity under specific conditions. Government effectiveness and innovation have positive effects on productive capacities. These findings underscore the need for balanced policies that leverage global economic integration while ensuring geopolitical stability, and offering nuanced insights to guide strategic decision-making for sustained economic cycles. 2024 Elsevier Inc. -
Social entrepreneurial opportunity recognition among higher education students: scale development and validation
Purpose: This study aims to develop and validate a multidimensional scale to measure the motivating factors that lead to opportunity recognition in social entrepreneurship among higher education institute (HEI) students. Design/methodology/approach: The scale was developed through two phases; in phase 1, semi-structured interviews with social entrepreneurs and aspiring students were conducted to explore themes for item generation. Phase 2 included developing and validating the scale using exploratory (EFA) and confirmatory factor analysis (CFA). The sample included HEI students (n = 300 for EFA, n = 300 for CFA) with either academic background or volunteering experiences in social entrepreneurship. Findings: A 24-item scale is developed in the study, with six factors measuring the motivating factors influencing opportunity recognition in social entrepreneurship: life experiences, social awareness, social inclination, community development, institutional voids and natural option for a meaningful career. Research limitations/implications: The scale facilitates the development of theories and models in social entrepreneurship. The scale also enables policymakers and social entrepreneurship educators to understand the motivating factors that lead to opportunity recognition among students. It would help them to provide target-specific support to students. Originality/value: To the best of the authors knowledge, this study is the first attempt to develop a scale that measures opportunity recognition in social entrepreneurship based on specific motivating factors. The study used the model by Yitshaki and Kropp (2016) as the conceptual framework. This study is the first attempt to triangulate the models findings using a quantitative methodology and through the development of a measurement scale. Besides, the scale adds value to social entrepreneurship research, which lacks empirical research on HEI students. 2024, Emerald Publishing Limited. -
Representation of Cancer in the Digital Space
[No abstract available] -
Synthesis and Characterisation of SrAl2O4: Eu3+ Orange-Red Emitting Nanoparticles
The current study involves the synthesis and characterisation of europium doped strontium aluminate nanophosphors using the solid-state reaction method with varying concentrations of europium. The existence of the SrAl2O4 phase in all samples was verified using X-ray diffraction and FTIR analysis. The lattice parameters as well as phase fractions were determined using Rietveld refinement. Surface morphology was studied using field emission scanning electron microscope. Using the Tauc plot method acquired from the diffuse reflectance spectra, the band gaps of the samples were determined and it was found that the doped samples possess lower band gaps compared to the host. Our findings demonstrate that these nanophosphors exhibiting bright orange-red emission under UV excitation with quantum efficiency 70.68%, can be applied for display and fluorescence imaging. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2023. -
Study of nanofluid flow in a stationary cone-disk system with temperature-dependent viscosity and thermal conductivity
The substantial temperature gradient experienced by systems operating at relatively high temperatures significantly impacts the transport characteristics of fluids. Hence, considering temperature-dependent fluid properties is critical for obtaining realistic prediction of fluid behavior and optimizing system performance. The current study focuses on the flow of nanofluids in a stationary cone-disk system (SCDS), taking into account temperature-dependent thermal conductivity and viscosity. The influence of Brownian motion, thermophoresis, and Rosseland radiative flux on the heat transport features are also examined. The Reynolds model for viscosity and Chiam's model for thermal conductivity are employed. The Navier-Stokes equation, the energy equation, the incompressibility condition, and the continuity equation for nanoparticles constitute the governing system. The Lie-group transformations lead the self-similar ordinary differential equations, which are then solved numerically. Multi-variate non-linear regression models for the rate of heat and mass transfers on the disk surface were developed. Our study reveals a notable decrease in the rate of heat and mass transfer when pre-swirl exists in the flow. The significant influence of nanofluid slip mechanisms on the effective temperature and nanofluid volume fraction (NVF) within the system is highlighted. Furthermore, the variable viscosity property enhances the temperature and NVF of the SCDS. 2024 Author(s). -
Sustainable biodegradation of textile dye reactive blue 222 by the novel strain Enterobacter CU2004, isolated from the industrial waste: A design of experiment based optimization study and characterisation of metabolites
Reactive Blue 222 (RB222) is widely used in textile industries and hence a common recalcitrant pollutant in the industrial effluent. Bioremediation of this dye is of significance as its one of the complex dyes with high molecular weight. In the present study, we isolated a novel bacterial strain Enterobacter CU2004 from the industrial waste and characterize using16S rRNA gene sequencing. Its potential to dye degradation was evaluated in a simple minimal salt media with the parameters namely dye concentration (1001000 ppm), pH (49), temperature (1555C), Carbon source (Lactose, Sucrose, Glucose, Starch, and Fructose), and Nitrogen source (Casein, Yeast extract, Peptone, Tryptone, Ammonium sulphate, and Urea) in a 24 h culture. Finally, data obtained were extended to design of experiment based optimization for the degradation efficacy of Enterobacter CU2004 and to validated design space was established. The novelty is in optimizing the design space parameters for highest percentage of degradation ?90% by the bacterial isolate Enterobacter CU2004 were finalized as 3037C temperature, 133249 ppm dye concentration, Lactose as Carbon source, Yeast extract as Nitrogen source, and the pH as 8. Microbial dye degradation was confirmed by FTIR, HPLC and GCMS studies. Further studies revealed the dye intermediates and the potential of Enterobacter CU2004 toward the degradation of complex, high molecular weight industrial dye RB222. 2024 Vasantha Veerappa Lakshmaiah, et al. -
Highly secured authentication and fast handover scheme for mobility management in 5G vehicular networks
The Fifth Generation (5 G) networks exhibit high flexibility and diversity in their design and deployment strategies. Transitions between base stations (BSs), heterogeneous networks (HetNets) and other cellular networks provide significant vulnerabilities and expose users to substantial risks associated with cybersecurity attacks. This article evaluates current handover authentication methods in the context of 5 G networks while proposing a set of security criteria for handover authentication. This study presents a novel authentication technique called SHK (Secure Handover Key) that utilizes SDNs (Software Defined networks). The proposed scheme integrates recycled lightweight dynamic key cryptography and combines security features such as perfect forward secrecy and robustness to leakages. The significance of the proposed approach is assessed in terms of computations, communications, signals, and energy costs on 5 G mobility applications and Vehicular Communication Networks (VCNs). The scheme employed in this study demonstrates enhanced security measures and improved changeover performance compared to conventional schemes. 2024 Elsevier Ltd -
Mapping the landscape of tourism cities research: a bibliometric analysis of the International Journal of Tourism Cities
Purpose: This research addresses the pressing need for comprehensive studies in the rapidly evolving field of city tourism. This study aims to understand the overall performance of the International Journal of Tourism Cities (IJTC), the structure of knowledge in city tourism research and the prevalent themes and trends arising from IJTC. Design/methodology/approach: A bibliometric analysis was conducted to scrutinize the publication patterns in IJTC. This involved examining parameters such as the annual count of published articles, the keywords used in them and their respective authors. Findings: The findings reveal that IJTC has a growing and diverse publication output, establishing itself as a reputable and influential publication within urban tourism research. The results reflect various aspects and themes in city tourism research. Research limitations/implications: The study has certain limitations. The data used for analysis was obtained exclusively from the Scopus database. The analysis was conducted using only one software package, Bibliometrix. Other software packages may offer different features for bibliometric analysis. The study relied exclusively on quantitative methods for data analysis. Qualitative methods could have provided more nuanced interpretations of the data. Practical implications: Comparative analyses could be conducted between IJTC and other journals within urban tourism or related disciplines. Such research would yield valuable insights into the current state of the field and aid in identifying areas warranting further investigation. Social implications: The findings from this study can inform the decisions and actions of various stakeholders involved in urban tourism. Practitioners and policymakers can draw from this research to make informed decisions. Existing and emerging authors can identify relevant topics for their research. Readers can access pertinent information for their needs. Originality/value: This study offers a unique contribution by thoroughly comprehending the performance of IJTC between 2015 and 2023. It progresses the existing body of knowledge on city tourism research by examining its current status and future trends. 2023, International Tourism Studies Association. -
Functional characterization of Malabar grouper (Epinephelus malabaricus) interferon regulatory factor 9 involved in antiviral response
IRF9 is a crucial component in the JAK-STAT pathway. IRF9 interacts with STAT1 and STAT2 to form IFN-I-stimulated gene factor 3 (ISGF3) in response to type I IFN stimulation, which promotes ISG transcription. However, the mechanism by which IFN signaling regulates Malabar grouper (Epinephelus malabaricus) IRF9 is still elusive. Here, we explored the nd tissue-specific mRNA distribution of the MgIRF9 gene, as well as its antiviral function in E. malabaricus. MgIRF9 encodes a protein of 438 amino acids with an open reading frame of 1317 base pairs. MgIRF9 mRNA was detected in all tissues of a healthy M. grouper, with the highest concentrations in the muscle, gills, and brain. It was significantly up-regulated by nervous necrosis virus infection and poly (I:C) stimulation. The gel mobility shift test demonstrated a high-affinity association between MgIRF9 and the promoter of zfIFN in vitro. In GK cells, grouper recombinant IFN-treated samples showed a significant response in ISGs and exhibited antiviral function. Subsequently, overexpression of MgIRF9 resulted in a considerable increase in IFN and ISGs mRNA expression (ADAR1, ADAR1-Like, and ADAR2). Co-immunoprecipitation studies demonstrated that MgIRF9 and STAT2 can interact in vivo. According to the findings, M. grouper IRF9 may play a role in how IFN signaling induces ISG gene expression in grouper species. 2024 Elsevier B.V. -
Novel deep eutectic solvent catalysed Single-Pot open flask synthesis of Tetrasubstituted-1H-Pyrroles
Pyrrole and its analogs have garnered immense attention due to their multifaceted biological significance and versatile applications, ranging from medicinal agents to fundamental biological pigments. Despite their prominence, pyrrole synthesis with multiple substituents is complex and calls for innovative approaches to green chemistry. This study delves into synthesizing novel 3,5-dimethyl-1H-pyrroles via multicomponent reactions (MCRs) employing deep eutectic solvents (DES). Due to their eco-friendly nature, these DESs provide a safer substitute for traditional solvents. Specifically, a novel three-component DES (3CDES) was formulated, showcasing promising catalytic activity for multiple cycles with excellent product generation. The synergy between MCR and DES elucidates their combined potential in fostering a sustainable and efficient green synthesis route with the E-factor of 0.1699. 2024 Elsevier B.V. -
Globalisation and carbon dioxide emissions inequality in OECD countries
Economic growth has been crucial in contributing to carbon dioxide (CO2) emissions from the Industrial Revolution, and it affects CO2 emissions heterogeneously with different income levels. Therefore, studying the role of economic growth on inequality in carbon emissions is imperative. This paper analyses the determinants of CO2 emissions inequality in the panel dataset of 37 Organisation for Economic Co-operation and Development (OECD) countries from 1990 to 2019. Age dependency, globalisation, and institutional quality reduce CO2 inequality in the OECD economies. However, gross domestic product per capita increases CO2 inequality. The results are robust to utilise different panel data estimation techniques. This paper provides the first evidence in the literature of determinants of CO2 inequality across the OECD countries. It is suggested that governments in the OECD economies offer a blueprint for a sustainable society of green economic growth. Other potential policy implications are also discussed. 2023 John Wiley & Sons Ltd. -
Impact of the operational parameters of a dual fuel engine operating on a blend of Water Hyacinth biodiesel and Mesua ferrea biodiesel with hydrogenA clean development mechanism
The study was conducted to uncover the emission, combustion, and performance features of the blend of Water Hyacinth biodiesel and Mesua Ferrea seed oil biodiesel with Hydrogen addition on a diesel engine in dual fuel. Pilot fuel is a blend of 50% Water Hyacinth biodiesel and 50% Mesua Ferrea seed oil biodiesel. A single-cylinder compression ignition engine was modified to operate on dual fuel mode with hydrogen. Variations of engine operating parameters such as injection timing, and engine load were performed. The study was conducted with three pilot fuel injection timings (23, 26, and 29bTDC) and variable engine loadings (20%100% with an increment of 20%) at an injection pressure of 200 bar and compression ratio of 18. The results indicated that the maximum brake thermal efficiency of 28.11% and a replacement of liquid fuel by 85% was obtained for the WHMF blend powered dual fuel diesel engine at pilot fuel injection timings of 26bTDC at 100% load. HC, CO, and smoke emissions are reduced with hydrogen due to faster combustion. On the other hand, there was a slight increase in NOx emissions noticed with hydrogen enrichment. 2024 Hydrogen Energy Publications LLC -
Additively Composite Model Objective Function for Routing Protocol for Low-Power and Lossy Network Protocol
The Internet of Things (IoT) networks always operate within the context of diverse and constrained characteristics of the devices. Low-Power and Lossy Networks (LLNs) constitute a network architecture commonly utilized in IoT application deployments, facilitating networking and the establishment of paths for data transmission. The Routing Protocol for Low-Power and Lossy Networks (RPL) demonstrates promising capabilities for LLN network operations, supporting IPv4 and IPv6-enabled services. The RPL protocol constructs a Destination Oriented Directed Acyclic Graph (DODAG) logical routing topology based on defined Objective Function (OF) metrics. Routing operations within the DODAG utilize these metrics and constraints to select parent nodes and calculate optimal routes between two nodes. Standardized OFs have traditionally focused on either parent node selection or routing objectives within the DODAG, often treating load balancing and bottleneck optimization separately. However, their combined impact on RPL's effectiveness has been overlooked. This paper introduces an Adaptively Composite Objective Function (AC-OF) approach that considers the combined objectives of DODAG load balancing and optimized routing operations. Through simulation evidence, the paper presents improved network parameters. The AC-OF implementation brings out significant results in the form of a balanced DODAG topology and it has good impacts on data transmission, control overhead messages, parent switching, delay, energy consumption, and node lifetime. 2024 Totem Publisher, Inc. All rights reserved. -
Nonlinear Rayleigh-Bard magnetoconvection of a weakly electrically conducting Newtonian liquid in shallow cylindrical enclosures
A study of nonlinear axisymmetric Rayleigh-Bard magnetoconvection in a cylindrical enclosure filled with a dilute concentration of carbon-based nanotubes in a weakly electrically conducting Newtonian liquid heated from below for various aspect ratios is carried out. Cylindrical geometry is the prototype for heat storage devices and thermal coolant systems with a controlled environment. There is an analogy between porous media and magnetohydrodynamic problems and hence Rayleigh-Bard magnetoconvection problem is practically important. The solution of the velocity and the temperature is in terms of the Bessel functions of the first kind and hyperbolic functions that are further used to study the marginal stability curves, heat transport, and the dynamical system. Symmetric and asymmetric boundaries of the realistic-type are considered on the horizontal and vertical bounding surfaces. The results of these boundaries are compared with those of the idealistic-type which are symmetric. A unified analysis approach is adopted for all boundary combinations in deriving the Lorenz model and studying the nonlinear dynamics. The time-dependent Nusselt numbers incorporating the effect of the curvature of the cylinder accurately captures the enhanced heat transport situation in the regular convective regime. Further, the influence of various parameters on the indicators of chaos such as the rH-plots, Lorenz attractor, bifurcation diagram, and the time series plot is investigated. The rH-plots clearly point to the appearance of chaos and also assist in determining its intensity and periodicity. The trapping region of the solution of the Lorenz model having the shape like that of a rugby-ball is highlighted in the paper. The size of the ellipsoid shrinks with increase in the strength of the magnetic field and also depends on the boundary conditions. 2024