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Bromelain improves the growth, biochemical, and hematological profiles of the fingerlings of Nile Tilapia, Oreochromis niloticus
A 6-week-long feeding trial experiment was conducted to study the efficacy of Bromelain, a blend of proteolytic enzymes present in pineapple wastes on growth performance, biochemical, and hematological profiles of the fingerlings of Nile tilapia, Oreochromis niloticus. For this, 240 Nile tilapia fingerlings (9 0.11 cm) were fed a commercial diet, supplemented with different levels of pineapple peel extract (PPE) at 1:0, 1:1, 1:2, and 1:3 ratios. After 45 days of the feeding trial, growth parameters, biochemical constituents, and the level of blood cells were assessed. It was found that the growth parameters such as weight gain, feed efficiency ratio, and specific growth rate were increased (p < 0.05) along with the total protein and amino acid content and few hematological parameters; whereas the feed conversion ratio was found to be reduced significantly (p > 0.05) without changing the white blood cell count with PPE supplementation. Thus, the PPE can be a potential feed supplement in Nile tilapia aquaculture. 2022 Gopal Raaj et al. -
Message framing and COVID-19 vaccine acceptance among millennials in South India
Vaccine hesitancy and refusal remain a major concern for healthcare professionals and policymakers. Hence, it is necessary to ascertain the underlying factors that promote or hinder the uptake of vaccines. Authorities and policy makers are experimenting with vaccine promotion messages to communities using loss and gain-framed messages. However, the effectiveness of message framing in influencing the intention to be vaccinated is unclear. Based on the Theory of Planned Behaviour (TPB), this study analysed the impact of individual attitude towards COVID-19 vaccination, direct and indirect social norms, perceived behavioural control and perceived threat towards South Indian millennials intention to get vaccinated. The study also assessed the effect of framing vaccine communication messages with gain and loss framing. Data was collected from 228 Millennials from South India during the COVID-19 pandemic from September to October 2021 and analysed using PLS path modelling and Necessary Condition Analysis (NCA). The findings reveal that attitudes towards vaccination, perceived threat and indirect social norms positively impact millennials intention to take up vaccines in both message frames. Further, independent sample t-test between the framing groups indicate that negative (loss framed message) leads to higher vaccination intention compared to positive (gain framed message). A loss-framed message is thus recommended for message framing to promote vaccine uptake among millennials. These findings provide useful information in understanding the impact of message framing on behavioural intentions, especially in the context of vaccine uptake intentions of Millennials in South India. Copyright: 2022 Prakash et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. -
Phyllanthus Emblica Extract Protects the Rat Liver Cells Against the Toxicity of Monosodium Glutamate: Experimental Evidence
Background: Monosodium glutamate (MSG), used widely in the food industry, is a threat to the public health. We investigated whether the MSG administration depletes non-enzymatic antioxidants, i.e., vitamins C and E in the liver of Wistar albino rats. We also examined the restorative effect of the ethanolic extract of Phyllanthus emblica (P. emblica). Methods: Wistar albino rats (n=42) were adapted and then randomly divided into seven groups of: 1) control, 2, 3, 4) MSG treatment, and 5, 6, 7) combined MSG and P. emblica extract treatment. All rat groups were treated daily for 120 days. They were orally administered either MSG alone or MSG plus the extract combined. The rats were then sacrificed and the liver was harvested from each group, and homogenized to examine the levels of vitamins C and E in the liver, using RP-HPLC method. Results: The vitamins C and E levels significantly declined (P<0.05) in the liver of MSG treated groups compared to those of the control rats. The combined treatment (extract + MSG) at low and moderate doses restored the vitamin C levels but it restored vitamin E only at the low dose (P<0.05). Conclusions: This study clearly demonstrated the deterioration of non-enzymatic antioxidants, i.e., vitamins C and E in the rats' liver after chronic exposure to MSG. The findings support the toxic effect and oxidative stress due to MSG exposure to the liver and the beneficial effect of the extract of P. emblica that inhibits the MSG's harmful effect on the liver. The Author(s), 2022. -
Synchronous learning and asynchronous learning during COVID-19 pandemic: a case study in India
Purpose: This research aims to study the students' perspectives on synchronous and asynchronous learning during the COVID-19 Pandemic. Both synchronous and asynchronous learning approaches used in online education have positive and negative outcomes. Hence, the aim is to study online education's positive and negative consequences, reflecting sync and async approaches. This research followed a mixed research approach. The key stakeholders of this research are the Indian educational institutions and students. Design/methodology/approach: This research collected data from the students undergoing synchronous and asynchronous learning amidst the COVID-19 Pandemic. The data were collected (N=655) from various students taking online classes during the pandemic. A questionnaire survey was distributed to the students through online platforms to collect the data. In this research, the authors have collected data using simple random sampling, and the same has been used for data analysis using SPSS version 26. The collected data were exposed to a factor analysis using a principal component analysis technique to reduce the vast dimensions. Findings: The study findings show that synchronous learning is sometimes stressful, placing more responsibility on students mainly because of the increased screen time. At the same time, asynchronous learning allows the students to self-explore and research the topics assigned to them. Students also felt that asynchronous activities create a burden because of many written assignments to be submitted within a short period. Overall, the COVID-19 pandemic has been challenging for the students and the teachers. However, teachers have helped students to learn through digital platforms. The majority of the respondents opined that technological disruptions and death in the family circle had been significant reasons for not concentrating during online classes. However, the combination of synchronous and asynchronous learning has led to a balanced education. Practical implications: Higher education has undergone multiple transformations in a short period (from March 2020, 2021 and beyond). Educational institutions underwent a rapid transition in remote teaching and learning in the initial stages. As time progressed, educational institutions did course navigation where they relooked into their course plans, syllabus and brought a structural change to match the pandemic requirements. Meanwhile, educational institutions slowly equipped themselves with infrastructure facilities to bring academic integrity. At present, educational institutions are ready to face the new normality without disrupting services to society. Social implications: Educational institutions create intellectual capital, which is important for the development of the economy. In the light of COVID-19, there are new methods and approaches newly introduced or old methods and approaches, which are reimplemented, and these approaches always work for the benefit of the student community. Originality/value: The authors collected data during the COVID-19 pandemic; it helped capture the students' experience about synchronous and asynchronous learning. Students and faculty members are newly exposed to synchronous and asynchronous learning, and hence, it is essential to determine the outcome that will help many stakeholders. 2022, Cassandra Jane Fernandez, Rachana Ramesh and Anand Shankar Raja Manivannan. -
Controlling RayleighBard Magnetoconvection in Newtonian Nanoliquids by Rotational, Gravitational and Temperature Modulations: A Comparative Study
The effect of three different types of time periodic modulations on the RayleighBard magnetic system involving Newtonian nanoliquids is studied. Multiple-scale analysis (homogenization method) is used to arrive at the GinzburgLandau equation. The curiosity in the work is to know the individual effects of (1) rotation, (2) gravity and (3) temperature modulations on RayleighBard magnetoconvection in weakly electrically conducting Newtonian nanoliquids. A significant effort in this research is devoted toward linear and nonlinear stability analyses as well as the homogenization method which leads to the GinzburgLandau evolution equation. Although several studies have concluded similar results for nanoliquids compared with those of pure base fluids, many fundamental issues like the choice of phenomenological models for the thermo-physical properties and the best type of nanoparticles are not well understood. This research focuses on several important issues involving mathematical and computational problems arising in heat transfer analysis in the presence of nanoliquids. Effects of various nanoliquid parameters, frequency and amplitude of modulation on heat transport are analyzed. This investigation focuses on five nanoliquids, with water as a carrier liquid and five nanoparticles, viz. copper, copper oxide, silver, alumina and titania. Enhanced heat transport was observed for rotation, gravity and temperature modulations. In the case of rotation modulation, it is found that increase in the amplitude of modulation results in a decrease in the critical Rayleigh number and thereby to an increase in the mean Nusselt number. The increase in the amplitude of the gravity modulation is shown to enhance the heat transport, whereas increase in frequency is to inhibit the heat transport. Two types of temperature modulations are considered, viz. in-phase (synchronous) and out-of-phase (asynchronous) temperature modulations with the assumption that the boundary temperatures vary sinusoidally with time. The amplitudes of modulation are considered to be very small. In the case of in-phase modulation, there is no significant difference between the heat transports in the presence and in the absence of temperature modulation. On this reason, out-of-phase temperature modulation is used to either enhance or diminish heat transport by suitably adjusting the frequency and phase difference of the modulated temperature. The effect of magnetic field, in all three cases of modulations, is to inhibit the onset of convection and thereby diminish the heat transport. 2022, King Fahd University of Petroleum & Minerals. -
A survey on the intersection graphs of ideals of rings
Let L(R) denote the set of all non-trivial left ideals of a ring R. The intersection graph of ideals of a ring R is an undirected simple graph denoted by G(R) whose vertices are in a one-to-one correspondence with L(R) and two distinct vertices are joined by an edge if and only if the corresponding left ideals of R have a non-zero intersection. The ideal structure of a ring reects many ring theoretical properties. There is so much research that has been conducted during the last decade to explore the properties of G(R). This is a survey of the developments in the study on the intersection graphs of ideals of rings since its introduction in 2009. 2022 by the authors. -
How Can Small and Medium Enterprises Effectively Implement Corporate Social Responsibility?: An Indian Perspective
The current study is a strategic approach to corporate social responsibility (CSR); the aim is to put forward the factors of CSR activities that enhance its effectiveness for small and medium enterprises (SMEs). To achieve this objective, the factors were extracted from the literature and described along with trusteeship theory of Mahatma Gandhi, and an exploratory study was conducted and data were collected using structured questionnaire based on pretested scale from 158 SMEs and tested using partial least square regression (PLSR). The statistics shows the overall model fit, and the findings indicate a significant relationship with effective CSR. The results of the study are in accordance with the previous research work, and we also find that environment-related CSR and partnership are crucial for the effectiveness of CSR in SMEs, stakeholders role are important and SMEs CSR practice is still informal. The variables identified from study will help SMEs in establishing a formal approach towards CSR and meeting the needs of business and society in the twenty-first century. 2019 International Management Institute, New Delhi. -
Influence of electrochemical co-deposition of bimetallic Pt-Pd nanoclusters on polypyrrole modified ITO for enhanced oxidation of 4-(hydroxymethyl) pyridine
Bimetallic Pt-Pd nanoparticles were dispersed on polypyrrole coated indium-tin oxide coated polyethylene terephthalate sheets (ITO-PET sheets). The excellent filming property of pyrrole gives a high porous uniform active area for the proper adsorption of bimetallic transition metal nanoparticles. Electrochemical behavior of the modified electrodes was determined using cyclic voltammetry and impedance studies. The physicochemical properties of the modified electrodes were analyzed by scanning electron microscopy, X-ray diffraction spectroscopy, X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy. To study the electrochemical oxidation of 4-(hydroxymethyl) pyridine in the presence of sodium nitrate in aqueous acidic medium, the modified electrode was used. It is evident from the study that the modified electrode shows better electrochemical activity towards the oxidation of 4-(hydroxymethyl) pyridine. 2022 The Royal Society of Chemistry. -
Improvement of Automatic Glioma Brain Tumor Detection Using Deep Convolutional Neural Networks
This article introduces automatic brain tumor detection from a magnetic resonance image (MRI). It provides novel algorithms for extracting patches and segmentation trained with Convolutional Neural Network (CNN)'s to identify brain tumors. Further, this study provides deep learning and image segmentation with CNN algorithms. This contribution proposed two similar segmentation algorithms: one for the Higher Grade Gliomas (HGG) and the other for the Lower Grade Gliomas (LGG) for the brain tumor patients. The proposed algorithms (Intensity normalization, Patch extraction, Selecting the best patch, segmentation of HGG, and Segmentation of LGG) identify the gliomas and detect the stage of the tumor as per taking the MRI as input and segmented tumor from the MRIs and elaborated the four algorithms to detect HGG, and segmentation to detect the LGG works with CNN. The segmentation algorithm is compared with different existing algorithms and performs the automatic identification reasonably with high accuracy as per epochs generated with accuracy and loss curves. This article also described how transfer learning has helped extract the image and resolution of the image and increase the segmentation accuracy in the case of LGG patients. Copyright 2022, Mary Ann Liebert, Inc., publishers 2022. -
Advanced Computational Method to Extract Heart Artery Region
Coronary artery disease, also known as coronary heart disease, is the thinning or blockage of heart arteries, which is generally caused utilizing the build-up of fatty material called plaque. The coronary angiogram test is currently the most utilized method for identifying the stenosis status of arteries in the heart. The objective of the proposed hybrid segmentation method is to extract the artery region of the heart from angiogram imagery. Numerous angiogram video clips have been considered in the dataset in this research work. These video clips were acquired from a healthcare center with the due consent of patients and the concerned healthcare personnel. Most angiogram videos consist of unclear images, or the contents are generally not clear, and medical experts fail to acquire accurate information about the damages or blocks formed in arteries due to the same reason. A hybrid computational method to extract well-defined images of heart arteries using Frangi and motion blur features from angiogram imagery has been proposed to address this issue. Fifty patients' information has been used as the dataset for experimentation purposes in this research work. The enhanced Frangi filter is used on the dataset to obtain edge information to enhance the input image based on the Hessian matrix. Further, the motion blur helps in automatically tracking/tracing the pixel direction using the optical flow method. In this method, the complete structure of the artery is extracted. The results, when compared to the existing methods, have proven to be novel and more optimal. 2022 Seventh Sense Research Group. -
Alkali-activated bricks made with mining waste iron ore tailings
In India, the enormous growth in the housing sector has put tremendous pressure on construction materials such as bricks. Conventional brick production methods include fired bricks and cement blocks. However, conventional methods significantly contribute to environmental carbon emissions and therefore alternative brick production methods have caught the attention of several researchers. Furthermore, the waste generated in various industries can be a useful resource for the construction industry, and in particular, voluminous waste is generated during the beneficiation stage of iron ore concentrate, which can be integrated into the construction industry to achieve sustainable practice. With this quest in mind, this study proposes the utilization of mining waste iron ore tailing (IOT) in alkali-activated bricks. For this purpose, six different brick compositions were synthesized with fly ash, GGBS, and IOT along with Na2SiO3 sol. The raw materials were characterized using various techniques such as X-ray fluorescence (XRF), X-ray diffraction (XRD), scanning electron microscope (SEM), and particle size analysis (PSA). Furthermore, a series of standard tests were conducted on the developed bricks to evaluate their strength and durability properties. The developed bricks have presented a maximum compressive strength of 18.45 MPa and minimum water absorption of 12.6%. Besides, the alkali-activated bricks have shown excellent resistance to brick ageing which was attributed to improvement in the microstructure of bricks due to the filling up of voids with products of the polymeric reaction. Finally, it was interesting to notice that with 8% Na2SiO3 as an alkaline activator and with the combination of fly ash and GGBS more than 50% IOT can be utilized to produce good quality bricks at ambient curing conditions. 2022 The Authors -
Through the Lens of Recession 2.0: Diversification Dynamics Between the Leading Asian Stock Markets
The focus of this article is to analyse the inter-linkages between eight leading stock markets in Asian continent from the period of July 2011 to February 2018. This period holds relevance as this was the time when Recession 2.0 set in, which adversely affected the developed economies; however, the developing economies withstood the crisis without much of an impact. Co-integration and Granger causality tests were conducted to probe the inter-linkages. Study revealed a positive impact on Asian stock market indices collectively on each of the indexes. The highest number of unidirectional causalities was to KOPSI and NIFTY from rest of the stock indices. Results confirmed that no co-integration relationship existed among the selected indices indicating favourable diversification opportunities. Thus, the study fosters global market participants and policymakers to consider the nitty-gritties of stock market integration so as to benefit from international stock market diversification in the Asian region. 2022 Management Development Institute. -
Curcumin inhibits spike protein of new SARS-CoV-2 variant of concern (VOC) Omicron, an in silico study
Background: Omicron (B.1.1.529), a variant of SARS-CoV-2 is currently spreading globally as a dominant strain. Due to multiple mutations at its Spike protein, including 15 amino acid substitutions at the receptor binding domain (RBD), Omicron is a variant of concern (VOC) and capable of escaping vaccine generated immunity. So far, no specific treatment regime is suggested for this VOC. Methods: The three-dimensional structure of the Spike RBD domain of Omicron variant was constructed by incorporating 15 amino acid substitutions to the Native Spike (S) structure and structural changes were compared that of the Native S. Seven phytochemicals namely Allicin, Capsaicin, Cinnamaldehyde, Curcumin, Gingerol, Piperine, and Zingeberene were docked with Omicron S protein and Omicron S-hACE2 complex. Further, molecular dynamic simulation was performed between Crcumin and Omicron S protein to evaluate the structural stability of the complex in the physiological environment and compared with that of the control drug Chloroquine. Results: Curcumin, among seven phytochemicals, was found to have the most substantial inhibitory potential with Omicron S protein. Further, it was found that curcumin could disrupt the Omicron S-hACE2 complex. The molecular dynamic simulation demonstrated that Curcumin could form a stable structure with Omicron S in the physiological environment. Conclusion: To conclude, Curcumin can be considered as a potential therapeutic agent against the highly infectious Omicron variant of SARS-CoV-2. 2022 Elsevier Ltd -
Smart Edge Computing for 5g/6g Satellite IOT for Reducing Inter Transmission Delay
5G/6G communication are first generation high speed wireless communication network which integrates the aerial data, terrestrial data and maritime data via satellite to IoT cellular devices. Technological motivation tends to increase the satellites day by day for supporting most of global applications. These applications highly relay on satellite data for processing users request and giving appropriate outcome to the users. World grows very fastly with new technologies which makes demand for fastest data communication. Handling the satellite IoT data is worthiest research problem and it must be paid with more attention. At present inter satellite communication face high delay with lower data utilization rate. The effective utilization of data generated by satellite IoT is processed using our proposed intelligent model called smart edge computing (SEC-5G) for 5G. The SEC-5G embeds with satellite for reducing the data transfer limitation and delay in inter satellite communication. In this research we highly concentrate on satellite IoT data and its problem. Our proposed system reduces the limitation in inter satellite data communication rate which makes higher delay in data processing and utilization. In this article, smart edge computing is designed for satellite IoT using SDN/NFV and deep convolutional neural network (DCNN) with logical ring construction. The task uses SDN/NFV model to choose edge node, cloud node in the smart edge computing. Based on training data, DCNN works on SEC-5G software model. Smart architecture helps to increase the performance, scalability, reliability of satellite edge computing model. This architecture works with machine learning model and helps to improve the future satellite speed on data processing. The performance of the proposed is compared with existing Ground 5G. Evaluated outcome shows proposed embedded satellite outperforms in data communication. 2021, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature. -
Synergistic effects of graphene oxide grafted chitosan & decorated MnO2 nanorods composite materials application in efficient removal of toxic industrial dyes
In this study, we designed a heterogeneous graphene oxide (GO) grafted on chitosan decorated with MnO2 nanorods (?-MnO2NRs/GO-Chit) composite materials and its ability to remove the cationic and anionic toxic dyes from wastewaters were analysed. The synthesised materials presented an effective stabilization of active MnO2 nanorods (NRs) on the GO-Chit surface. The synthesised materials were detailed characterised by several spectroscopic and microscopic techniques such as, FT-IR, P-XRD, SEM, TEM, Raman, TGA, XPS, BET, CO2-TPD and UVVisible analysis. In addition, ?-MnO2NRs/GO-Chit material is successfully applied in removal of industrial ionic dyes such as amido black 10B (AB) and methylene blue (MB), respectively. The dye adsorption experiments confirmed that the GO-Chit/?-MnO2 NRs material exhibited remarkably high adsorption capacity in efficient removal of cationic dye methylene blue (MB) and anionic dye amido black 10B (AB). The maximum MB dye removal (97%) process completed in 24 min at C0 = 30 mgL?1, but in the case of AB the maximum dye removal (80%) process was reached in 700 min. Over GO-Chit/?-MnO2 NRs hybrid material, a maximum theoretical monolayer adsorption (qmax values is 328.9 mg g?1) of MB was calculated from the Langmuir isotherm equation. In case MB, a faster adsorption and 2.18 times maximum adsorption capacity was achieved than that of AB10 dye. The enhanced adsorption over ?-MnO2NRs/GO-Chit is due to the increased surface functionalities (i.e., oxygen-containing groups), high basicity and strong electrostatic forces between MnO2 nanorods and GO-Chit. Furthermore, ?-MnO2NRs/GO-Chit hybrid material displayed good stability after 10 successive adsorption tests. 2022 Elsevier Ltd -
Vapor growth and optimization of supersaturation for tailoring the physical properties of stoichiometric Sb2Se3 crystalline habits
The evolution of different morphologies (fibers, whiskers, needles, and spherulites) of antimony selenide (Sb2Se3), devoid of foreign chemical elements, was explored by the physical vapor deposition (PVD) method, employing an indigenously assembled tubular furnace, which showed layer growth mode as per the metallurgical and scanning electron micrographs. Supersaturation for crystallization was optimized by precisely controlling the difference in temperatures of nutrient and growth zones, ?T = TN ? TG, where ?T = 125 to 350C. The strain and dislocation density of the crystals were evaluated from the crystallographic data. Monophase nature has been confirmed by Rietveld refinement analysis of the PXRD findings, using Full Proof software. UVVis-NIR and PL spectra of the morphologies revealed band gap, Eg in the range, 1.151.18eV. Among these habits, good-quality whiskers bearing flat faces of appreciable crystallinity, stoichiometry, thermal stability and mechanical strength were produced due to the periodic deposition of atoms associated with the progression of smooth vaporsolid (v?) interface as evident from PXRD, EDAX, XPS, TGA and microindentation analyses. Hall effect measurements resulted in obtaining appreciable values of electrical parameters, ? = 145.36 ? cm and n = 7.39 1018cm?3 for PV applications. Moreover, optical studies justified direct transition with adequate photon absorption which promises the suitability of whiskers as absorbers in the energy conversion process. 2022, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature. -
Evaluation of Clove Phytochemicals as Potential Antiviral Drug Candidates Targeting SARS-CoV-2 Main Protease: Computational Docking, Molecular Dynamics Simulation, and Pharmacokinetic Profiling
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus can cause a sudden respiratory disease spreading with a high mortality rate arising with unknown mechanisms. Still, there is no proper treatment available to overcome the disease, which urges the research community and pharmaceutical industries to screen a novel therapeutic intervention to combat the current pandemic. This current study exploits the natural phytochemicals obtained from clove, a traditional natural therapeutic that comprises important bioactive compounds used for targeting the main protease of SARS-CoV-2. As a result, inhibition of viral replication effectively procures by targeting the main protease, which is responsible for the viral replication inside the host. Pharmacokinetic studies were evaluated for the property of drug likeliness. A total of 53 bioactives were subjected to the study, and four among them, namely, eugenie, syzyginin B, eugenol, and casuarictin, showed potential binding properties against the target SARS-CoV-2 main protease. The resultant best bioactive was compared with the commercially available standard drugs. Furthermore, validation of respective compounds with a comprehensive molecular dynamics simulation was performed using Schringer software. To further validate the bioactive phytochemicals and delimit the screening process of potential drugs against coronavirus disease 2019, in vitro and in vivo clinical studies are needed to prove their efficacy. Copyright 2022 Chandra Manivannan, Malaisamy, Eswaran, Meyyazhagan, Arumugam, Rengasamy, Balasubramanian and Liu. -
Responding to pandemic challenges: leadership lessons from multinational enterprises (MNEs) in India
Purpose: The business sector plays a major role in achieving comprehensive economic development goals in emerging economies. Consequently, the effects of business responses to the COVID-19 pandemic are receiving increasing research attention from an organizational management development perspective. This article aims to examine the role of leadership in charting the course in an extraordinary crisis context. Design/methodology/approach: Using institutional leadership theory, leadership contingency theory and dynamic leadership capability theory, the authors present a research framework that defines macrochallenges and organizational level responses and outcomes. The article adopts a case study approach, which includes the identification of four target companies and conducting in-depth interviews with senior management professionals within those companies at different time periods. Findings: Based on the interviews, the steps that Indian companies adopted to respond to the COVID-19 challenge are identified. Expanding the insight from the case study, the findings suggest that although feeling overwhelmed at first, organizational leaders combine prudent (i.e. timely and speedy actions for survival first) and bold (i.e. future envisioning for expansion and growth) actions enabling these firms to weather two waves of the COVID-19 pandemic in India. Originality/value: These multiple case studies are unique in exploring MNEs from different industries. This study also highlights the dynamic relationships between leadership practices, risk management strategies and performance outcomes based on a sound theoretical model and rigorous study methods. 2022, Emerald Publishing Limited. -
Solutions for time-fractional coupled nonlinear Schringer equations arising in optical solitons
In this work, an efficient novel technique, namely, the q-homotopy analysis transform method (q-HATM) is applied to obtain analytical solutions for a system of time-fractional coupled nonlinear Schringer (TF-CNLS) equations with the time-fractional derivative taken in the Caputo sense. This system of equations incorporate nonlocality behaviors which cannot be modeled under the framework of classical calculus. With numerous important applications in nonlinear optics, it describes interactions between waves of different frequencies or the same frequency but belonging to different polarizations. We first establish existence and uniqueness of solutions for the considered time-fractional problem via a fixed point argument. To demonstrate the effectiveness and efficiency of the q?HATM, two cases each of two time-fractional problems are considered. One important feature of the q?HATM is that it provides reliable algorithms which can be used to generate easily computable solutions for the considered problems in the form of rapidly convergent series. Numerical simulation are provided to capture the behavior of the state variables for distinct values of the fractional order parameter. The results demonstrate that the general response expression obtained by the q?HATM contains the fractional order parameter which can be varied to obtain other responses. Particularly, as this parameter approaches unity, the responses obtained for the considered fractional equations approaches that of the corresponding classical equations. 2021 The Physical Society of the Republic of China (Taiwan) -
Strength and durability properties of geopolymer paver blocks made with fly ash and brick kiln rice husk ash
In India the generation of agro waste rice husk ash is abundant. The utilization of rice husk ash in development of geopolymer binders can be suitable to alleviate the environmental problems associated with disposal of rice husk ash. Further, the utilization of rice husk ash generated from the stacks of brick kilns has not been addressed in past, particularly in development of geopolymer binders. This study proposes development of geopolymer paver (GEOPAV) blocks utilizing brick kiln rice husk ash (BKRHA). It presents fresh, mechanical and durability properties of GEOPAV blocks blended with fly ash, BKRHA, natural aggregates, NaOH and Na2SiO3 solution, and cured in both sundry and room temperature conditions. Microstructural analysis using scanning electron microscope (SEM) and X-ray diffraction (XRD) was adopted to study the influence of BKRHA on hardened properties of GEOPAV blocks. The results show that addition of BKRHA reduce the workability of GEOPAV mixes due to micro porous surface with honeycombed structure of BKRHA particles. The addition of BKRHA showed negligible improvement in compressive strength of GEOPAV blocks. However, the major advantage was observed with improved split tensile strength and flexural strength for GEOPAV blocks with BKRHA. Further, the durability properties in terms of resistance to acid and frost attack was significantly improved with the addition of BKRHA in GEOPAV blocks. Such improvements can be attributed to high amounts of amorphous silica in BKRHA which contribute towards dissolution and formation of polymeric gel, and thereby serve as a binder to enhance the geopolymer matrix making it dense. Finally, all the developed GEOPAV blocks satisfy the IS 156582021 specification requirements and perform much better when compared to commercially available paver blocks. 2021 The Authors