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Analysis of factors impacting firm performance of MSMEs: lessons learnt from COVID-19
Purpose: The micro, small and medium scale enterprises (MSMEs) faced various challenges in the ongoing COVID-19 pandemic, making it challenging to remain competitive and survive in the market. This research develops a model for MSMEs to cope with the current pandemic's operational and supply chain disruptions and similar circumstances. Design/methodology/approach: The exhaustive literature review helped in identifying the constructs, their items and five hypotheses are developed. The responses were collected from the experts working in MSMEs. Total 311 valid responses were received, and the structural equation modeling (SEM) approach was used for testing and validating the proposed model. Findings: Critical constructs identified for the study are-flexibility (FLE), collaboration (COL), risk management culture (RMC) and digitalization (DIG). The statistical analysis indicated that the four latent variables, flexibility, digitalization, risk management culture and collaboration, contribute significantly to the firm performance of MSMEs. Organizational resilience (ORS) mediates the effects of all the four latent variables on firm performance (FP) of MSMEs. Practical implications: The current study's findings will be fruitful for the manufacturing MSMEs and other firms in developing countries. It will enable them to identify the practices that significantly help in achieving the firm performance. Originality/value: The previous researches have not considered the effect of organizational resilience on the firm performance of MSMEs. This study attempts to fill this gap. 2022, Emerald Publishing Limited. -
Facile fabrication of stable wettability gradients on elastomeric surfaces for applications in water collection and controlled cell adhesion
We have developed a simple and effective method to prepare stable wettability gradients on an elastomeric soft substrate, polydimethylsiloxane (PDMS). In our method, a partially cured PDMS film composed of a definite ratio of elastomer and crosslinking agent was heated over a hot surface with a temperature gradient. This causes differential thermal curing of the PDMS film and the water contact angle (wettability) of the resultant surface showed gradual variation across the length. This method allows us to design and fabricate wettability gradients with rationally controlled directionality and shapes (e.g., linear and radial gradients). The stability of the wettability gradients was studied and a chemical treatment method was developed to enhance the stability at room temperature. Stable wettability gradients prepared through this method can find applications as reliable platforms and scaffolds offering controlled or directional wetting and adhesion. We have demonstrated the practical applications of the wettability gradients in directional water collection, controlled crystallization of materials, and controlled cell adhesion of HeLa cells, osteoblasts and NIH/3T3 cells. The multi-functional characteristics of these wettable gradients are expected to be handy in other domains using soft materials and interfaces also. 2023 The Royal Society of Chemistry. -
Quantum tunneling rotor as a sensitive atomistic probe of guests in a metal-organic framework
Quantum tunneling rotors in a zeolitic imidazolate framework ZIF-8 can provide insights into local gas adsorption sites and local dynamics of porous structure, which are inaccessible to standard physisorption or x-ray diffraction sensitive primarily to long-range order. Using in situ high-resolution inelastic neutron scattering at 3 K, we follow the evolution of methyl tunneling with respect to the number of dosed gas molecules. While nitrogen adsorption decreases the energy of the tunneling peak, and ultimately hinders it completely (0.33 meV to zero), argon substantially increases the energy to 0.42 meV. Ab initio calculations of the rotational barrier of ZIF-8 show an exception to the reported adsorption sites hierarchy, resulting in anomalous adsorption behavior and linker dynamics at subatmospheric pressure. The findings reveal quantum tunneling rotors in metal-organic frameworks as a sensitive atomistic probe of local physicochemical phenomena. 2023 authors. Published by the American Physical Society. -
A comprehensive review of AI based intrusion detection system
In today's digital world, the tremendous amount of data poses a significant challenge to cyber security. The complexity of cyber-attacks makes it difficult to develop efficient tools to detect them. Signature-based intrusion detection has been the common method used for detecting attacks and providing security. However, with the emergence of Artificial Intelligence (AI), particularly Machine Learning, Deep Learning and ensemble learning, promising results have been shown in detecting attacks more efficiently. This review discusses how AI-based mechanisms are being used to detect attacks effectively based on relevant research. To provide a broader view, the study presents taxonomy of the existing literature on Machine Learning (ML), Deep learning (DL), and ensemble learning. The analysis includes 72 research papers and considers factors such as the algorithm and performance metrics used for detection. The study reveals that AI-based intrusion detection methods improve accuracy, but researchers have primarily focused on improving performance for detecting attacks rather than individual attack classification. The main objective of the study is to provide an overview of different AI-based mechanisms in intrusion detection and offer deeper insights for future researchers to better understand the challenges of multi-classification of attacks. 2023 -
Dynamic Offloading Technique for Latency-Sensitive Internet of Things Applications using Fog Computing
Internet of Things (IoT) has evolved as a novel paradigm that provides com-putation power to different entities connected to it. IoT offers services to multiple sectors such as home automation, industrial automation, traffic management, healthcare sector, agriculture industry etc. IoT generally relies on cloud data centers for extended analytics, processing and storage support. The cloud offers highly scalable and robust platform for IoT applications. But latency sensitive IoT applications suffer delay issues as the cloud lies in remote location. Edge/fog computing was introduced to overcome the issues faced by delay-sensitive IoT applications. These platforms lie close to the IoT network, reducing the delay and response time. The fog nodes are usually distributed in nature. The data has to be properly offloaded to available fog nodes using efficient strategies to gain benefit from the integration. Differ-ent offloading schemes are available in the literature to overcome this prob-lem This paper proposes a novel offloading approach by combining two effi-cient metaheuristic algorithms, Honey Badger Algorithm (HBA) and Fla-mingo Search Algorithm (FSA) termed as HB-FS algorithm. The HB-FS is executed in an iterative manner optimizing the objective function in each it-eration. The performance evaluation of the proposed approach is done with different existing metaheuristic algorithms and the evaluations show that the proposed work outperforms the existing algorithms in terms of latency, response time and execution time. The methodology also offers better degree of imbalance with proper load balancing under different conditions. 2023 Authors. All rights reserved. -
The Mediating Effect of Employee Engagement: How Employee Psychological Empowerment Impacts the Employee Satisfaction? A Study of Maldivian Tourism Sector
This study aims to examine the mediation of employee engagement on the relationship between employee psychological empowerment and employee job satisfaction, which helps to retain more customers with better service. An empirical analysis was done on Maldivian resorts, and 243 employees were randomly selected from different resorts in the Maldives. The proposed model was tested using IBM SPSS AMOS 25. The results indicate that psychological empowerment had a significant effect on job satisfaction of the resort employees through employee engagement. The Maldivian economy is based on the tourism sector, and a significant amount of gross domestic product (GDP) depends on the tourism sector. Resorts and guesthouses are the power hubs for the economic development of the country, and employees are the primary source of service providers to tourists, which helps the resorts to retain their tourists. Hence, this study concludes that employees psychological empowerment and employees engagement are crucial to improve employee satisfaction. 2023 IMI. -
Coca-Cola product placement strategy backfires a case of celebrity activism
Research methodology: A secondary research method was used to collect data for this case. The authors have made use of newspaper articles and published articles written by journalists and experts which are available in the public domain. Case overview/synopsis: Instances of celebrity activism such as athlete activism are rising. Social media has amplified the voice of celebrities and given them a personal channel to directly communicate with their fans without any media censorship. The same is true especially concerning endorsement by sports superstars, who now seem to have a mind of their own, independent of the official line of clubs, tournament organizers or sponsoring companies. This case discusses the embarrassment and financial loss faced by soft drinks giant Coca-Cola due to the public snub by football superstar Cristiano Ronaldo during an official press conference of the EURO 2020 championship. Complexity academic level: Undergraduate and postgraduate students studying marketing management and brand management courses in business management and commerce streams can use this case. This case can also be used for marketing specialization students at the undergraduate and postgraduate levels. 2023, Emerald Publishing Limited. -
Spirocyclic isatin-derivative analogues: Solvation, structural, electronic, topological, reactivity properties, and anti-leukaemic biological evaluation
The present work investigates, via computational methods, three spirocyclic isatin derivatives with ?-methylene-?-butyrolactone cores, whose synthesis, experimental data and structural-activity relationships have been reported, to compare their properties and biological action. DFT (Density Functional Theory) studies, including geometry optimisation, FMO Analysis, theoretical UV spectral analysis, NBO and NLO studies, are performed using Gaussian 09 W with a standard basis set. The IEFPCM model is employed to investigate the solvent effect on the reactivity and stability of the compounds. Topological analyses are also performed, including ELF, LOL, RDG and charge transfer studies. ADME profiling is performed using SwissADME online tool. Anti-leukaemic target proteins are selected and docked with the title compounds to understand their suitability to act against leukaemic conditions. 2023 Elsevier B.V. -
Impact of terminal group on azobenzene liquid crystal dimers for photo-responsive optical storage devices
Three new series of photo responsive dimers bearing different terminal functional groups (-CN, -COOEt, -OMe) and variable aliphatic spacers have been synthesized and investigated in detail. The molecular structures of the new materials were proved using different spectroscopic techniques and their liquid crystal self-assembly was characterized using differential scanning calorimetry (DSC), polarized light microscope (POM) and X-ray diffraction (XRD). Moreover, their photo switching behaviour was investigated in details in solution. The results revealed that, almost all members of the dimeric materials are mesomorphic exhibit either nematic or both smectic A and nematic phases. Under UV illumination the materials show interesting photo-switching properties, reaching a photo-stationary state in 40 s and a thermal back-relaxation time of approximately 35 h in solution. Finally, a fabricated device authenticates the potential of the reported materials for optical storage devices. 2023 Elsevier B.V. -
Lithiated indole derivative in reduced graphene oxide framework as efficient electrode for lithium-ion battery
The traditional wet-chemical approach was used to synthesise N,N?-bis-Ind[?1H-indol-3-ylmethylidene]benzene-1,2-diamine (N,N?-bis-IBD), which was then lithiated using ball milling. The physical and spectrochemical characteristics of the as-prepared materials in lithiated and unlithiated forms were found to be considerably different. The activity of the lithiated N,N?-bis-IBD electrode material towards battery application was investigated using cyclic voltammetry (CV) and galvanostatic charge potential limit (GCPL) studies. The electrochemical studies on this electrode material revealed the active strong redox characteristics and anodic behaviour in aqueous electrolyte. At 100 cycles in aqueous medium, the lithiated moiety exhibited an impressive battery performance with a discharge capacity of 277 mAhg?1. Interestingly, addition of 20 wt % reduced graphene oxide (rGO) to lithiated N,N?-bis-IBD sample greatly improved the battery performance showing a high discharge capacity of 766 mAhg?1 after 100 cycles. The improved electrochemical performance implicates rGO-mixed lithiated indole-based composite as an effective anode material for lithium-ion battery (LIBs) application. 2023 Elsevier B.V. -
A Novel Survey for Young Substellar Objects with the W-band Filter. VI. Spectroscopic Census of Substellar Members and the IMF of the ? Orionis Cluster
Low-mass stars and substellar objects are essential in tracing the initial mass function (IMF). We study the nearby young ? Orionis cluster (d ? 408 pc, age ? 1.8 Myr) using deep near-infrared (NIR) photometric data in the J, W, and H bands from WIRCam on the Canada-France-Hawaii Telescope. We use the water absorption feature to select brown dwarfs photometrically and confirm their nature spectroscopically with IRTF-SpeX. Additionally we select candidate low-mass stars for spectroscopy and analyze their membership and those of literature sources using astrometry from Gaia DR3. We obtain NIR spectra for 28 very-low-mass stars and brown dwarfs and estimate their spectral type between M3 and M8.5 (masses ranging between 0.3 and 0.01 M ?). Apart from these, we also identify five new planetary-mass candidates which require further spectroscopic confirmation of youth. We compile a comprehensive catalog of 170 spectroscopically confirmed members in the central region of the cluster, for a wide mass range of ?19-0.004 M ?. We estimate the star-to-brown-dwarf ratio to be ?4, within the range reported for other nearby star-forming regions. With the updated catalog of members we trace the IMF down to 4 M Jup and we find that a two-segment power law fits the substellar IMF better than a log-normal distribution. 2023. The Author(s). Published by the American Astronomical Society. -
PANI/Bi2O3 polymeric nanocomposite for the reduction of 4-nitrophenol
Nitro-aromatics pollute the aquatic environment and reach human beings via drinking water. 4-Nitrophenol (4-NP) is the most common pollutant among them and can be reduced to non-toxic 4-aminophenol in the presence of sodium borohydride (NaBH4). Polyaniline/bismuth oxide (PANI/Bi2O3) nanocomposite is synthesized from aniline and Bi2O3 by chemical oxidative polymerization. The composition and structural properties of PANI/Bi2O3 composite are identified by various characterization methods like X-ray powder diffraction, fourier transform infrared spectroscopy, thermogravimetric analysis , and zeta potential analysis. The synthesized PANI/Bi2O3 shows high catalytic efficiency towards the reduction of 4-NP in the presence of NaBH4 under optimized reaction conditions. The numerous active sites on the composite and the presence of PANI/Bi2O3 interface are the reasons for the reduction of 4-NP to 4-aminophenol. A complete degradation is achieved in 15min with 0.1g of the composite. This nanocomposite shows good stability for five cycles without losing efficiency. PANI/Bi2O3 possesses a high reduction capacity and can be used to reduce other nitro organic pollutants in water. The aim of the study is to study the effective catalytic reduction of 4-NP using PANI/Bi2O3. Graphical abstract: [Figure not available: see fulltext.] 2022, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature. -
Study of Surface Waves Transmission in Orthotropic Bilateral Structure
This research work depicts the study of transmission of surface Rayleigh elastic waves in orthotropic layer having corrugated boundary resting over a pre-stressed orthotropic substrate. As a result, this study is made to spot the Rayleigh elastic wave transference under the consequence of initial stress in orthotropic material medium. Consequence of corrugation parameter, layer width parameter, initial stress parameter and density parameter on Rayleigh elastic wave propagation are marked separately. Distinguished parametric graphs are drawn following numerically the analytical study to exhibit the influence of distinct considered parameters on Rayleigh wave phase velocity of propagation. Frequency equations are obtained in closed determinant form under certain boundary conditions. Some particular cases have been deduced. Parametric results on the phase velocities yield a significant conclusion of which some are: (a) The corrugation parameter affects the more on phase velocity in comparison to initial stress (b) The orthotropic height stiffening can monotonically decrease the speed of phase. The present models may be applicable in engineering composites and for seismologist. 2023, The Author(s), under exclusive licence to Springer Nature India Private Limited. -
Valorization of pineapple peel waste for fungal pigment production using Talaromyces albobiverticillius: Insights into antibacterial, antioxidant and textile dyeing properties
The present study explores natural pigments as sustainable alternatives to synthetic textile dyes. Due to their therapeutic applications and easy production, fungal pigments have gained attention. However, data on pigment production using solid-state fermentation and optimization is limited. Milk whey was used to grow Talaromyces sp., followed by an evaluation of pigment production in solid and liquid media. Pineapple peels were used as a cost-effective substrate for pigment production, and a one-factor-at-a-time approach was used to enhance pigment production. Pineapple peel-based media produced 0.523 0.231 mg/g of pigment after eight days of incubation. The crude pigment had promising antibacterial and significant antioxidant properties. The extraction fungal pigment's possible use as an eco-friendly textile dye was assessed through fabric dyeing experiments with different mordants. This work contributes to the valorization of agricultural waste and provides insight into using fungal pigments as sustainable alternatives to synthetic textile dyes. 2023 Elsevier Inc. -
A colorimetric chemosensor for distinct color change with (E)-2-(1-(3-aminophenyl)ethylideneamino)benzenethiol to detect Cu2+ in real water samples
The study reports the synthesis of chemosensor (E)-2-(1-(3-aminophenyl)ethylideneamino)benzenethiol (C1), a highly sensitive, colorimetric metal probe that shows distinct selectivity for the detection of Cu2+ ion in various real water samples. Upon complexation with Cu2+ in CH3OH/H2O (60:40 v/v) (aqueous methanol), the C1 demonstrate significant enhancement in the absorption at 250nm and 300nm with a color change from light yellow to brown which was visualized using naked-eye. Therefore, these properties make C1 as an effective candidate for on-site Cu2+ ions detection. The emission spectrum of C1 illustrated TURN-ON recognition of Cu2+ with a limit of detection (LOD) of 46nM. Furthermore, Density Functional Theory (DFT) calculations were performed to better understand the interactions between C1 and Cu2+. The obtained results suggested that the electron clouds present around the NH2 innitrogen and sulfur in SH play a pivotal role in the formation of a stable complex. The computational results were in good agreement with the experimental UVvisible spectrometry results. Graphical abstract: [Figure not available: see fulltext.] 2023, The Author(s), under exclusive licence to The Japan Society for Analytical Chemistry. -
Testing for the Bidirectional Relationship Between FDI in Services and Trade in Services: Evidence from Emerging Economies
We examine the two-way links between foreign direct investments (FDI) in services and trade in services for 26 emerging economies from 2003 to 2015 using sectoral and sectoral disaggregated FDI data. Within a multivariate framework, we use panel unit root tests, recently developed heterogeneous panel cointegration and panel vector error correction model (VECM). Our results confirmed the cointegrating relationship between trade in services, FDI in services, financial services FDI and nonfinancial services FDI. We find the existence of long-run unidirectional causality from trade in services to FDI in services. However, the disaggregated analysis shows a bidirectional link between nonfinancial services FDI and trade in services in the short run. Still, there is no causality between financial services FDI and trade in services both in the short run and long run. The result also shows the evidence of unidirectional causality running from trade in services to nonfinancial services FDI in the long run. It implies that sectoral decomposition matters in the FDItrade nexus in emerging economies. JEL Codes: G20, F14, G20, F23 2022 Indian Institute of Foreign Trade. -
MoS2-TiO2 Nanocomposites for Enhanced Photo-electrocatalytic Hydrogen Evolution
The investigation on the designing and fabrication of highly efficient electrocatalysts for hydrogen evolution reaction (HER) is critical for future applications in renewable sustainable energy. The present work reports the hydrothermal synthesis of two-dimensional MoS2 and MoS2-TiO2 nanostructures. The as-prepared nanostructures were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), Raman analysis, UV-vis-NIR, and photoluminescence spectrophotometry and vibrating sample magnetometer (VSM). Systematic electrochemical measurements for HER were performed and MoS2-TiO2 nanocomposites demonstrated the lowest onset potential in comparison with MoS2. The results suggest that the nanofusion interface between MoS2 nanoflakes and TiO2 nanoparticles induced an efficient charge transfer from the conduction band of MoS2 to TiO2 and favored the reduction of H+ at active sites. We believe the present work can open up new possibilities that would provide deep insights for the rational design of 2D materials-based catalysts for energy storage and conversion applications. 2023 The Electrochemical Society (ECS). Published on behalf of ECS by IOP Publishing Limited. -
Individual Effect of Spatially Periodic Vertical Surface Temperatures and Nanoparticles on Natural Convection in Water
This paper considers the thermo-convective boundary-layer flow (BLF) of a water-copper mono-nanofluid over a flat vertical surface which is subjected to three types of periodic temperature variations described by the sinusoidal, sawtooth, and triangular waveforms. The temperature of the fluid at the flat surface is greater than the surrounding ambient temperature. The governing equations describing the BLF have been reduced to a non-similar form using an appropriate stream function formulation. The Keller-Box method is used to obtain numerical solution of the boundary-value problem. The effect of the pertinent parameters on the nature of the flow and the heat transfer has been discussed using actual thermophysical data. The results about the shear-stress and heat transfer rate at the surface are presented as well. To study the nature of BLF, the velocity and thermal boundary-layers, the streamline and isotherm plots have been considered, which reveal that the nanoparticle volume-fraction, amplitude of surface temperature variations, and the Grashof number play a pivotal role in enhancing/diminishing heat transfer. The final outcome reveals that the heat transfer is highest for the sinusoidal waveform, followed by that of the triangular and then, the sawtooth. An important inference is that a symmetric periodic temperature distribution at the surface enhances heat transfer more than that of a constant surface-temperature. 2023 by ASME. -
Designing coordinatively unsaturated metal sites in bimetallic organic frameworks for oxygen evolution reaction
Metal organic frameworks (MOFs) are developing as promising catalysts for oxygen evolution reactions. A bimetallic electrocatalyst MOF using Ni and Cu as metal sources and 1,4-benzene dicarboxylic acid as a linker has been synthesized and evaluated for oxygen evolution reaction. Compared to monometallic MOFs, bimetallic MOFs participate more actively in electrocatalysis due to the higher abundance of active sites, local crystallinity, and lower long-range disorder. When utilized as oxygen evolution catalysts, NiCu MOFs have a low overpotential of 340 mV at 10 mA/cm2 and a low Tafel slope of 65 mV/dec. The study paves the way for the development of highly efficient catalysts for water splitting applications. 2023 Elsevier Ltd -
Populist Protests and the Dynamic Zero-COVID Policy: (Re)emerging Pragmatic Populism in China
Populist protests in the Peoples Republic of China (PRC) have recently emerged as a reaction against the Chinese authorities stringent measures under its dynamic zero-COVID policy. Besides the vehement criticism and protests against the dynamic zero-COVID policy, during some protests, there have been ensuing calls across the country for President Xi Jinping to step down. The article argues that this scenario can further deteriorate the overall political legitimacy of the Communist Party of China on a long-term basis. According to the article, the protests indicate the re-emergence of populism in the PRC, which incidentally and historically has parallels to the protests at Tiananmen Square, and the 1919 May Fourth Movement. The article theorizes John Deweys concept of pragmatic populism and the aspect of protests during the period, which inherently provides many ideational and relational facets with the recent protests in China. 2023 Jawaharlal Nehru University.