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Synthesis, Computational, and Photophysical Probing Studies on Mono-Azo Sulfonamides, and Their Antibacterial Activity
Abstract: Objective: Novel azo-linked substituted sulfonamides were synthesized via diazo coupling with the molecular formula (C9H10N4O2S2, C11H11N3O2S) and characterized by FT-IR, UV-vis, HR-MS, and 1H NMR spectroscopy techniques. The photophysical studies were carried out using experimental techniques. Absorption and fluorescence maxima of all the synthesized molecules were determined by using different solvents. Our synthesized mono-azo derivatives are interested in identifying the cellular target site for sulfonamides (F1-F2) and (P1-P2). The newly synthesized compounds were examined for their in vitro antibacterial activity against Staphylococcus aureus and Escherichia coli strains. Methods: In this study, we focused on the sulfonamide architecture. Antibacterial activity of compound (F1), (F2), (P1), and (P2) derivatives was studied by measuring the diameter of the inhibition zone, using the Disc-agar diffusion method. Results and Discussion: Density functional theory was used to demonstrate the electronic and optical properties of the synthesized molecules. In the correlation between the HOMOLUMO energy gap, the derivative (F1) shows a higher (3.9866 eV) and (F2) shows a lower (3.2063 eV) excitation energy. The synthesized compound (F1) looks into antibacterial activity, exhibited more zone inhibition 25 mm in the concentration 75 L/mL in gram-negative bacteria when compared with the common antibiotic Ciprofloxacin. Additionally, the results emerged from the in silico molecular docking studies the compound (F2) showed highest binding energy against cyclin-dependent kinase (?Gb = 9.8 kcal/mol). Conclusions: The synthesized four mono-azo sulfonamide derivatives (F1), (F2), (P1), and (P2) are reported in photophysical, CDFT, antibacterial, and molecular docking studies with relevant results. Pleiades Publishing, Ltd. 2024. -
Post-road traffic injury experiences and challenges faced by college students: A qualitative study in Madurai district, Tamil Nadu, India
Road traffic injuries (RTIs) are a pressing public health concern in India, leading to a rise in injury-related deaths, hospitalizations, and disabilities. India accounts for a significant portion of the world's fatal traffic accidents, with two-wheelers being involved in the majority of these accidents. The impact of non-fatal injuries on individuals extends beyond the bodily consequences of the injury and includes both the physical and psychological dimensions of the injury. The literature indicates the need for policy cascades and implementation framework for the prevention of road traffic injury. This study aimed to investigate the post-RTI experiences and challenges faced by college students who experienced road traffic injury during their college life by using a qualitative research approach in Madurai district, Tamil Nadu, India. The study found that college students who experienced RTIs faced a wide range of physical, emotional, and social difficulties. The study highlights the need for a more comprehensive and holistic approach to RTI prevention that takes into account the complex interplay of individual, environmental, and societal factors that contribute to RTIs. The study also underscores the urgent need to improve the quality and availability of healthcare and rehabilitation services for RTI survivors. 2024 John Wiley & Sons Australia, Ltd. -
FL-XGBTC: federated learning inspired with XG-boost tuned classifier for YouTube spam content detection
The problem of spam content in YouTube comments is an ongoing issue, and detecting such content is a critical task to maintain the quality of user experience on the platform. In this study, we propose a Federated Learning Inspired XG-Boost Tuned Classifier, FL-XGBTC, for YouTube spam content detection. The proposed model leverages the advantages of federated learning, which enables the training of a model collaboratively across multiple devices without sharing raw data. The FL-XGBTC model is based on the XGBoost algorithm, which is a powerful and widely used ensemble learning algorithm for classification tasks. The proposed model was trained on a large and diverse dataset of YouTube comments, which includes both spam and non-spam comments. The results demonstrate that the FL-XGBTC model achieved a high level of accuracy in detecting spam content in YouTube comments, outperforming several baseline models. Additionally, the proposed model provides the benefit of preserving user privacy, which is a critical consideration in modern machine-learning applications. Overall, the proposed Federated Learning Inspired XG-Boost Tuned Classifier provides a promising solution for YouTube spam content detection that leverages the benefits of federated learning and ensemble learning algorithms. The major contribution of this work is to demonstrate and propose a framework for showing a distributed federated classifier for the multiscale classification of youtube spam comments using the Ensemble learning method. The Author(s) under exclusive licence to The Society for Reliability Engineering, Quality and Operations Management (SREQOM), India and The Division of Operation and Maintenance, Lulea University of Technology, Sweden 2024. -
Transparent and lead-free Dy3+ doped lithium borate glasses for photon and neutron shielding applications
The exploration of trivalent rare-earth ion-doped lithium calcium borate glasses has surged recently due to their potential applications in solid-state lasers, medical imaging, and radiation shielding. This study focuses on transparent and lead-free Dy3+ doped lithium borate glasses for their efficacy as versatile radiation shields. Glasses with the chemical composition 50(Li2O): 20(CaO): 30?x(B2O3): x(Dy2O3) (x = 0.0, 0.1, 0.3, 0.5 and 1.0 mol% Dy2O3) were investigated. The structural changes in the lithium calcium borate glasses with Dy2O3 were investigated using Fourier transform infrared spectra of the synthesized glass samples. Experimental mass attenuation coefficients (?/?) of the glasses have been determined using NaI(Tl) detector spectrometer in the energy range of 0.356-1.332 MeV. Photon interaction parameters were computed using PAGEX software in the energy range of 0.015-15 MeV. Relative dose distribution (RDD) and specific absorbed fraction of energy (SAFE) were also investigated. Additionally, macroscopic fast neutron removal cross-sections ( ? R ) were computed to estimate neutron shielding efficiencies. The sample with 1 mol% Dy2O3(LBD1), displayed superior photon and neutron attenuation properties. Glasses with lower Dy2O3 doping concentrations (?1 mol%) showed comparable half-value layer and effective atomic number to reference materials with higher doping concentrations. Increasing Dy2O3 doping concentration improved photon shielding parameters, with ? R values ranging from 0.1460 to 0.1475 cm?1, higher than those of ordinary concrete, RS-360, and other reference materials. The results highlight the potential of Dy3+ doped lithium borate glasses as effective radiation shields. Further investigations on chemical combinations and Dy2O3 doping concentrations are warranted to fabricate glasses with enhanced properties. 2024 IOP Publishing Ltd. All rights, including for text and data mining, AI training, and similar technologies, are reserved. -
Artificial intelligence-based reverse logistics for improving circular economy performance: adeveloping country perspective
Purpose: Reverse logistics services are designed to move goods from their point of consumption to an endpoint to capture value or properly dispose of products and materials. Artificial intelligence (AI)-based reverse logistics will help Micro, Small, and medium Enterprises (MSMEs) adequately recycle and reuse the materials in the firms. This research aims to measure the adoption of AI-based reverse logistics to improve circular economy (CE) performance. Design/methodology/approach: In this study, we proposed ten hypotheses using the theory of natural resource-based view and technology, organizational and environmental framework. Data are collected from 363 Indian MSMEs as they are the backbone of the Indian economy, and there is a need for digital transformation in MSMEs. A structural equation modeling approach is applied to analyze and test the hypothesis. Findings: Nine of the ten proposed hypotheses were accepted, and one was rejected. The results revealed that the relative advantage (RA), trust (TR), top management support (TMS), environmental regulations, industry dynamism (ID), compatibility, technology readiness and government support (GS) positively relate to AI-based reverse logistics adoption. AI-based reverse logistics indicated a positive relationship with CE performance. For mediation analysis, the results revealed that RA, TR, TMS and technological readiness are complementary mediation. Still, GS, ID, organizational flexibility, environmental uncertainty and technical capability have no mediation. Practical implications: The study contributed to the CE performance and AI-based reverse logistics literature. The study will help managers understand the importance of AI-based reverse logistics for improving the performance of the CE in MSMEs. This study will help firms reduce their carbon footprint and achieve sustainable development goals. Originality/value: Few studies focused on CE performance, but none measured the adoption of AI-based reverse logistics to enhance MSMEs CE performance. 2024, Emerald Publishing Limited. -
Biological extraction of chitin from fish scale waste using proteolytic bacteria Stenotrophomonas koreensis and its possible application as an active packaging material
Chitin being the second most abundant polymer found in nature has extensive application and versatile material properties including biocompatibility. Extraction of chitin from diverse sources are majorly done using chemical extraction methods using high concentration of alkali that makes the method non eco-friendly and economically non-viable. This calls for eco-friendly methods of chitin extraction from cost-effective substrates through green methods. This research work presents a simplified one-step biological extraction of chitin from fish scales by successive fermentation using Stenotrophomonas koreensis isolated from soil. The fermentative approach for chitin extraction from fish scales using S. koreensis enzyme activity is not reported elsewhere in the available literature to the best of our knowledge. Chitin yield of 28% (w/w) was obtained after the successive fermentation. The extracted polymer was characterized using differential scanning calorimetry (DSC), Fourier transform infrared (FTIR), X-ray diffraction (XRD), and thermo gravimetric analysis (TGA). Furthermore, the possibility of converting extracted chitin into an active packaging material was explored by chemically, converting it to chitosan followed by analysis of its DPPH scavenging activity. The DPPH radical scavenging activity varied from 67.025 to 80.2%, which corresponds to 0.25 to 2mg/mL of chitosan. The chitosan films fabricated were subjected to biodegradation studies using soil burial method. Biodegradation rate of chitosan films was observed to be 21.49 0.62% (w/w) after 50days of incubation. Thus, the present research work highlights an integrated waste valorization strategy through microbial fermentation for commercially important biopolymer production. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2023. -
Fermented aquatic weed meal (FAWM) as a protein source in Asian Catfish Clarias batrachus diets: Impacts on growth, blood chemistry profile, liver and gut morphology and economic efficiency
The global aquaculture industry is increasingly seeking sustainable alternatives to fishmeal (FM) due to its high price and shortfall in supply. In this context, fermented aquatic weed meal (FAWM) could emerge as a viable plant protein source for aquafeed. Four isoproteic diets [30 % crude protein (CP)] were formulated, incorporating 50 % total protein from FAWM comprising fermented Azolla diet (D1), Pistia diet (D2), and Eichhornia diet (D3). The control diet (D0) did not contain FAWM. At the end of the 90 days feeding trial, their growth performance, whole-body proximate composition, gut microbial load, haemato-biochemical indices, liver and gut health, and economic efficiency were determined. Fish fed with D0 had significantly (p < 0.05) improved growth performance and feed utilization compared to other treatment groups. Meanwhile, the fish supplemented with D1 diet exhibited significantly (p < 0.05) higher final weight (g), specific growth rate (%/day), weight gain (%), total biomass (g), and protein efficiency ratio among the FAWM dietary groups. The D1 group also demonstrated the significantly (p < 0.05) highest whole-body CP (64.27 0.40 %) and lower crude lipid (8.24 0.28 %) compared to other test diets. The total bacteria (TB) and lactic acid bacteria (LAB) in the fish gut were found to be significantly (p < 0.05) higher in D1 group. Furthermore, most of the hemato-biochemical indices of fish were significantly (p < 0.05) affected by FAWM inclusions, with few exceptions. The histological findings indicated that amongst the FAWM groups, D1 fish exhibited improved intestinal health. Nonetheless, the gut of the control fish demonstrated substantially (p < 0.05) lower villi width and crypt depth than other treatments. The D1 and D2 diet groups had significantly improved liver health. Moreover, FAWM inclusion enhanced economic efficiency by considerably reducing farm feed cost (US$/kg) and increasing return on investment (%). In summary, dietary inclusion of fermented Azolla pinnata (D1) protein at 50 % in aquafeed promoted feed utilization, growth, health, and farm economics of Asian catfish fingerlings compared to other FAWM diets. 2024 The Authors -
Assessing the Effectiveness of Implied Volatility in Predicting Realised Return Volatility for Informative Decision-Making: Insights from the Nifty Bank Index
Implied volatility (IV) is crucial in option pricing models and serves as an essential tool for volatility traders to make informed decisions. However, its effectiveness in predicting realized return volatility is still debated. This study investigates the efficiency of implied volatility in forecasting realized return volatility in the Indian financial markets, specifically using Bank Nifty index options and also assesses the predictive capability of implied volatility against the realised volatility estimator. Utilizing data spanning five years, from January 2018 to December 2022. Finding of this study reveal that implied volatility significantly forecasts realized volatility, highlighting its efficacy as a forecasting tool. Moreover, historical volatility fails to enhance predictive power when combined with implied volatility. Nonetheless, caution should be exercised in generalizing these results to other markets or time periods, as further research is warranted. The study contributes to the ongoing discourse on implied volatility efficiency, offering practical insights for options traders and adding to the body of knowledge in financial economics. 2024, Iquz Galaxy Publisher. All rights reserved. -
Examining the moderating role of online celebrity trustworthiness and risk propensity in UTAUT2 framework: A mixed-method approach
Utilizing the Unified Theory of Acceptance and Use of Technology 2 (UTAUT2) framework, this research delved into the behavioral intentions and actual usage of fantasy sports gaming apps. The moderating influence of celebrity trustworthiness and risk propensity is also explored. The proposed hypotheses were tested using responses from a substantial sample of 460 sports fantasy gaming app users. The research deployed a mixed-method approach, combining both covariance-based and partial-least square structural equation modeling tech- niques. The investigation findings revealed an influence on behavioral intentions and actual use. Specifically, performance expectancy, hedonic motivation, habit, and social influence emerged as significant determinants affecting users intentions and behaviors. The study indicates a significant moderating role of celebrity trustworthiness on the relationship be- tween performance expectancy, hedonic motivation, habit, and social influence concerning behavioral intentions. Risk propensity moderated the relationship between behavioral inten- tions and actual usage behavior. As a contribution to the expanding literature, the research extended the application of the UTAUT2 framework to the context of sports fantasy gaming apps. The research also provides valuable insights for researchers and professionals associ- ated with sports fantasy gaming apps and future research directions. 2024 -
A top-down approach for studying the in-silico effect of the novel phytocompound tribulusamide B on the inhibition of Nipah virus transmission through targeting fusion glycoprotein and matrix protein
The proteins of Nipah virus ascribe to its lifecycle and are crucial to infections caused by the virus. In the absence of approved therapeutics, these proteins can be considered as drug targets. This study examined the potential of fifty-three (53) natural compounds to inhibit Nipah virus fusion glycoprotein (NiV F) and matrix protein (NiV M) in silico. The molecular docking experiment, supported by the principal component analysis (PCA), showed that out of all the phytochemicals considered, Tribulusamide B had the highest inhibitory potential against the target proteins NiV F and NiV M (-9.21 and ?8.66 kcal mol?1, respectively), when compared to the control drug, Ribavirin (-7.01 and ?6.52 kcal mol?1, respectively). Furthermore, it was found that Tribulusamide B pharmacophores, namely, hydrogen donors, acceptors, aromatic and hydrophobic groups, contributed towards the effective residual interactions with the target proteins. The molecular dynamic simulation further validated the results of the docking studies and concluded that Tribulusamide B formed a stable complex with the target proteins. The data obtained from MM-PBSA study further explained that the phytochemical could strongly bind with NiV F (-31.26 kJ mol?1) and NiV M (-40.26 kJ mol?1) proteins in comparison with the control drug Ribavirin (-13.12 and ?13.94 kJ mol?1, respectively). Finally, the results indicated that Tribulusamide B, a common inhibitor effective against multiple proteins, can be considered a potential therapeutic entity in treating the Nipah virus infection. 2024 Elsevier Ltd -
Designing Bifunctional Electrocatalysts Based on Complex Cobalt-Sulfo-Boride Compound for High-Current-Density Alkaline Water Electrolysis
In the quest to harness renewable energy sources for green hydrogen production, alkaline water electrolysis has emerged as a pivotal technology. Enhancing the reaction rates of overall water electrolysis and streamlining electrode manufacturing necessitate the development of bifunctional and cost-effective electrocatalysts. With this aim, a complex compound electrocatalyst in the form of cobalt-sulfo-boride (Co-S-B) was fabricated using a simple chemical reduction method and tested for overall alkaline water electrolysis. A nanocrystalline form of Co-S-B displayed a combination of porous and nanoflake-like morphology with a high surface area. In comparison to Co-B and Co-S, the Co-S-B electrocatalyst exhibits better bifunctional characteristics requiring lower overpotentials of 144 mV for hydrogen evolution reaction and 280 mV for oxygen evolution reaction to achieve 10 mA/cm2 in an alkaline electrolyte. The improved Co-S-B performance is attributed to the synergistic effect of sulfur and boron on cobalt, which was experimentally confirmed through various material characterization tools. Tafel slope, electrochemical surface area, turnover frequency, and charge transfer resistance further endorse the active nature of the Co-S-B electrocatalyst. The robustness of the developed electrocatalyst was validated through a 50 h chronoamperometric stability test, along with a recyclability test involving 10,000 cycles of linear sweep voltammetry. Furthermore, Co-S-B was tested in an alkaline zero-gap water electrolyzer, reaching 1 A/cm2 at 2.06 V and 60 C. The significant activity and stability demonstrated by the cobalt-sulfo-boride compound render it as a promising and cost-effective electrode material for commercial alkaline water electrolyzers. 2024 The Authors. Published by American Chemical Society. -
Investigation of corrosion behavior of Cenosphere reinforced iron based composite coatings
In the present study cenopshere was reinforced with FeCrNiC (Metco 42C) as matrix material and prepared four different feedstock powders such as FeCrNiC+0%Cenosphere, FeCrNiC+5%Cenosphere, FeCrNiC+10%Cenosphere and FeCrNiC+15%Cenosphere were coated by plasma spray technique on T22 substrate. Evaluation of the substrate and coatings potential under salt spray test was performed. Dense fog of 5% NaCl salt water was used to create a corrosive atmosphere within the chamber. The salt water's pH was kept constant at 6.57. The materials that underwent corrosion were examined using X-ray diffraction (XRD), and scanning electron microscopy (SEM). The FeCrNiC+15%Cenosphere and FeCrNiC+10%Cenosphere coatings exhibited reduced weight loss during a 168-h corrosion test compared to the FeCrNiC+5%Cenosphere, FeCrNiC coatings, and substrate. The excellent chemical stability and corrosion resistance of Cr23C6, SiO2, NiO, and Cr2O particles contribute to gradually avoid the formation of red rust on Fe-based coated samples with exposure approaches to 52 and 130 h. 2024 The Authors -
A Theoretical Article: Exploring the Evolutionary Dynamics of Couples and Family Therapy
This article provides a comprehensive review of how the field of family therapy has evolved, tracing its roots from early practices influenced by eugenics to its current diverse theoretical frameworks, which are ever-expanding. In the mid-20th century, family therapy expanded beyond its eugenic roots, embracing diverse theoretical frameworks and giving rise to various therapeutic modalities like behavioral and emotionally focused family and couples therapy. However, due to cultural disparities, these concepts and models cannot holistically capture the essence of family therapy in India. They do not compute the central role of the intergenerational subsystem or understand hierarchical dynamics. What is deemed okay in the Western context does not hold true in the Indian context. Postmodern approaches show a marked improvement in dealing with these problems in cultural adaptations of family and couples therapy by integrating diverse therapeutic practices, technological advances, and cultural and diversity-sensitive practices. However, despite these advancements, the adapted modalities have a scope for improvement, posing a pressing need for research that bridges this gap. Moving forward research should focus on family change mechanisms, symptom improvement factors, and prioritizing culturally sensitive approaches to meet the unique needs of Indian families. The Author(s) 2024. -
Unravelling Financial Resilience in India: A Multi-Group Analysis of Socio-Economic Factors
This research investigates the intricate relationship between financial literacy (FL), financial behavior (FB), and financial resilience (FR) across various socio-economic dimensions such as age, gender, income, and education. Building on previous studies, this paper focuses on how these factors may moderate the connection between FL and FR, with FB's role as a mediator. Conducted in Kerala, a region renowned for its high literacy rate, data from 270 participants was collected through an online survey using convenience sampling. The data was then analysed using IBM SPSS AMOS for Structural Equation Modelling, a widely accepted statistical tool. The analysis reveals robust evidence supporting positive relationships between FL-FB, FB-FR, and FL-FR. Additionally, FB partially mediates the FL-FR relationship. Multigroup analysis highlights distinct impacts across subgroups, emphasizing the nuanced interplay between these socioeconomic factors and financial outcomes. The study's conclusions, which highlight the urgent need for focused initiatives to improve financial literacy and promote responsible financial behaviour across a range of demographic groups, provide important new insights into financial dynamics. Such initiatives are essential for bolstering financial resilience and ensuring economic stability amidst varying socio-economic contexts and should be a priority for policymakers and practitioners. 2024, Iquz Galaxy Publisher. All rights reserved. -
Drivers and inhibitors of consumers adoption of AI-driven drone food delivery services
This study sheds light on the determinants of consumers adoption of artificial intelligence-driven drone food delivery service (AI-driven DFDS) using a mixed-methods approach. Interviews with hospitality industry professionals revealed several drivers and inhibitors of AI-driven DFDS adoption. Using these findings, we developed a theoretical model AI-driven DFDS adoption based on the premise of the behavioral reasoning theory and innovation resistance theory. The model was tested using data collected from 1240 consumers. The results suggest that drones relative advantage, perceived ubiquity, social influence, and green image positively influence attitudes and adoption. Risk, usage, and experience barriers have an adverse influence on attitudes and adoption. Consumers openness to new technology has a positive influence on reasons for using AI-driven DFDS. The research makes an important theoretical contribution to research on the adoption of AI-driven DFDS. The study also provides important practical implications for marketers and industry professionals. 2024 Elsevier Ltd -
A constrained multi-period portfolio optimization model based on quantum-inspired optimization
Multi-period portfolio optimization (MPO) is one of the most important problems to be solved to help investors select optimal portfolios for investment plans. The portfolios are influenced by the risk factors in the market and it is important to select optimal portfolios that can maximize the returns with minimum risk values. Other than the risk factor, there are several other influential factors that reduce the optimality of the portfolios. Therefore, by considering all possible constraints, this study proposes a multi-constraint MPO model that selects the optimal portfolio based on the asset returns. To solve the multi-constrained problem, a novel quantum-inspired whale optimization algorithm (QWOA) is introduced in this paper. The proposed algorithm enhances the traditional optimization model to work in a multi-constrained scenario. Here, quantum entanglement is adapted to reduce the slow convergence issue of whale optimization. Apart from considering only the risk factors, this paper also considers certain higher-order moments (HOM), such as skewness, kurtosis, transaction cost, diversification, boundary and budget constraints. These factors affect the portfolios as the market is dynamic, and timely changes are always seen. Thus, optimizing the mentioned factors aids in attaining an optimal portfolio. Empirical evaluations are performed, and the results suggested that the proposed model provided beneficial outcomes as compared with other algorithms like whale optimization algorithm (WOA), gray wolf optimization (GWO), fruitfly optimization algorithm (FOA), particle swarm optimization (PSO) and fruitfly algorithm (FA). The overall net return rate of the proposed model is always above 0.85% for different values of upper bounds, and the obtained Sharpe ratio, Sortino ratio, STARR ratio, information ratio, Shannon entropy, and downside deviation values of the proposed algorithm are 5.016254, 0.89327, ? 0.01987, 0.103826, 3.04452 and 0.2854. Hence, the proposed approach is highly effective for optimizing the constrained MPO. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024. -
Unravelling Post-harvest Ripening Metabolomics of a New White Variety Guava Fruit (Cv Arka Mridula) with Special Emphasis on Phenolics and Corresponding Antioxidants
The phenolic, antioxidant and metabolic profiling of a new white variety guava fruit Arka Mridula (AM) was performed during its storage at theroom temperature (28 2 C). The comparative profiles were generated at three ripening stages (pre-ripe, ripe and over-ripe) of the fruit. Generally, a steady decrease of the phenolic and antioxidant content from the pre-ripe to the ripe stage and a subsequent increase from the ripe to over-ripe stage was observed. Further, a powerful correlation between the phenolic content and antioxidant principles was noted through the principal component analysis. We could identify 53 compounds for the hydro-methanolic fruit extract through LC and GC-MS aided metabolic analysis, and the identified compounds were dominated by phenolics (~ 44%). The statistical analysis revealed that phytochemicals catechin, myricitrin, myricetin, kaempferol glycosides and n-hexadecanoic acid contributed significantly towards the ripening process of AM, during the storage. The present study is expected to provide important insight into the ripening biochemistry of AM. Subsequently, it may help in the future development of metabolically stable guava cultivars with extended post-harvest shelf life. Graphical Abstract: (Figure presented.) The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024. -
A dual-functional rhodamine B and azo-salicylaldehyde derivative for the simultaneous detection of copper and hypochlorite: synthesis, biological applications and theoretical insights
A multifunctional rhodamine derivative containing azo-salicylaldehyde (BBS) was designed and synthesized as a colorimetric and fluorescence turn-on probe for the selective detection of copper cations (Cu2+) and hypochlorite anions (OCl?) in aqueous media. In the presence of Cu2+, the probe BBS exhibited turn-on absorption and fluorescence change at 554 nm and 585 nm, respectively. The binding mechanism of BBS with Cu2+ induces the opening of a spirolactam ring in the rhodamine moiety by the formation of a metal-ligand complex, achieving 10-fold enhancement in fluorescence and quantum yield, along with a binding constant of 1 104 M?1 and a detection limit of 2.61 ?M. Addition of OCl? enhanced the absorbance and fluorescence intensities at 520 nm and 575 nm, respectively. The probe BBS underwent hypochlorite-mediated oxidation, followed by hydrolysis, resulting in the formation of rhodamine B itself, which is detectable by the naked eye via the color and fluorescence enhancement by 11-fold with a high quantum yield and a detection limit of 1.96 ?M. For practical applications, sensor BBS can be used to detect Cu2+ in water samples and on cotton swabs. For biological applications, the interaction of the BBS-Cu(ii) complex with transport proteins such as bovine serum albumin (BSA) and ct-DNA was investigated through UV-vis and fluorescence titration experiments. Additionally, the structural optimization of BBS and the BBS-Cu(ii) complex was demonstrated using DFT, and the interactions of the BBS-Cu(ii) complex with BSA and ct-DNA were analysed through theoretical docking studies. Bioimaging studies were conducted by capturing fluorescence images of BBS with Cu2+ and OCl? in a physiological medium containing living plant tissue using green gram seeds. 2024 The Royal Society of Chemistry. -
Where to Check Homework? The Emphasis on Supportive Feedback via Social Media by Teachers in CALL and Its Consequences on EFL Learners' Self-assessment, Academic Success, Academic Enjoyment
This study investigates the impact of Facebook-mediated supportive feedback on English as a Foreign Language (EFL) learners' self-assessment, academic enjoyment, and academic success in a Computer-Assisted Language Learning (CALL) context. Using a sequential exploratory methodology, this study holistically investigates the research objectives using qualitative and quantitative approaches. Two intact classrooms of lower-intermediate EFL students in an Iraqi language institute were selected; one class was designated as the experimental group receiving Facebook-mediated tasks and the other as the control group using conventional teaching strategies. Among the tools for data collecting were a teacher-made test, semi-structured interviews, and observation. Compared to the control group, the experimental groupwhich received extra Facebook-mediated tasks and conventional course materialsshowcased notably greater degrees of self-assessment, academic enjoyment, and academic success. Positive perceptions of Facebook-mediated interactions were found through the qualitative analyses of observations and interviews, thereby stressing learners' higher motivation, collaboration, and sense of community. The implications of the study are discussed. 2024, The Pacific Association for Computer Assisted Language Learning (PacCALL). All rights reserved. -
Controlled reaction time of TiO2 and cocktail co-sensitization for improved DSSC performance
Solar energy stands out as a promising alternative to traditional energy sources, with dye-sensitized solar cells (DSSC) proving to be a highly effective means of harnessing this renewable energy. However, recent studies highlight the efficacy of employing a photoanode with mixed phases of Titanium Dioxide (TiO2) nanoparticles in DSSCs. The conventional approach to preparing mixed-phase TiO2 involves a time-consuming process with high-temperature annealing. In the present work, a novel microwave-assisted solvothermal synthesis of mixed-phase TiO2, which significantly reduces the preparation time has been reported. Moreover, we have enhanced device performance by co-sensitizing carbon dots (CDs) with various natural dyes and synthetic dye. The device prepared using CDs co-sensitized with Brassica oleraceavar.capitataf.rubra exhibited comparable efficiency (3.66%) with that obtained for N719-sensitized DSSC (3.85%). Further improvement in efficiency (4.81%) was obtained on sensitizing CDs with N719 dye. The comprehensive analysis of device performance using these innovative methods represents a noteworthy advancement in the realm of solar energy harvesting, with unexplored possibilities that could shape the future of sustainable energy solutions. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024.