Multitask EfficientNet affective computing for student engagement detection
Affective computing; Behavioral analysis; Deep learning; Emotional analysis; Engagement analysis; Face detection; Multi task-EfficientNEtB0; Multi-modal student analysis
In the realm of education, feedback emerges as a pivotal component, serving to foster engagement and interaction while also facilitating the refinement of teaching methods to capture and maintain student attention. Traditional classroom assessment methods often struggle to accurately gauge the degree of comprehension among students during lectures, relying on manual comment collection that inherently carries the risk of inaccuracies. In response to this challenge, a novel system has been proposed, harnessing the power of Facial Emotion Recognition (FER) technology to capture student feedback. Within this framework, students are given a unique avenue to convey their emotions and reactions, employing facial expressions and gestures as the means to communicate. This innovative approach enables the analysis of students emotional responses and thereby provides invaluable insights into their comprehension levels, as well as the overall quality and engagement experienced during lectures. The approach takes shape through the utilization of Computer Vision techniques, with a particular focus on an unobtrusive methodology for assessing students overall engagement. Overcoming limitations of traditional assessment, our approach integrates compound scaling, employing the proposed Multitask EfficientNetB0 model recognized for its proved accuracy in emotion recognition (95.7%) and behavior analysis (96.3%) across diverse datasets (DAiSEE, iSED, iSAFFE). The behavioral classification system categorizes students into Engaged and Disengaged classes within a multi-class framework, providing nuanced insights into comprehension and Student engagement. Assessment metrics, including ROC Curves, Precision, Recall, and F1-Score, ensure a thorough evaluation. Our systems adaptability is demonstrated across varied educational environments, showcasing real-world efficacy in classrooms, laboratories, and seminar halls. The inclusion of MTCNN enhances face detection capabilities, facilitating robust analysis in dynamic scenarios. Expanding its applicability, the model has been put to the test in a range of educational settings, including classrooms, laboratory environments, and seminar halls, offering dual-capability analysis of both emotions and behavior. This comprehensive approach yields nuanced insights into student engagement and interaction, and its performance has been validated through real-world deployment within classrooms and seminars The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024.
Thiruthuvanathan, Michael Moses; Krishnan, Balachandran
Multimedia Tools and Applications;Volume;84;Issue;18;pp.19039-19063
Restricted Access; Hardcopy may be available in the library
https://doi.org/10.1007/s11042-024-19815-3 https://www.scopus.com/pages/publications/85198561288?origin=resultslist
Thiruthuvanathan M.M., Computer Science and Engineering, CHRIST University, Kanmanike, Karnataka, Bengaluru, 560029, India; Krishnan B., Computer Science and Engineering, CHRIST University, Kanmanike, Karnataka, Bengaluru, 560029, India
Design of automatic follicle detection and ovarian classification system for ultrasound ovarian images
Accuracy; Active contour; Biomedical instrumentation; Detection of PCOS; Follicle; Modified Otsu; Sensing systems; Ultrasound image
Polycystic Ovary Syndrome (PCOS) is a common reproductive and metabolic disorder characterized by an increased number of ovarian follicles. Accurate diagnosis of PCOS requires detailed ultrasound imaging to assess follicles size, number, and position. However, noise often needs to be improved on these images, complicating manual detection for radiologists and leading to potential misidentification. This paper introduces an automated diagnostic system for integration with ultrasound imaging equipment to enhance follicle identification accuracy. The system consists of two main stages: preprocessing and follicle segmentation. Preprocessing employs an adaptive Frost filter to reduce noise, while follicle segmentation utilizes a region-based active contour combined with a modified Otsu method. Unlike the conventional Otsu method, where the threshold value is selected manually, the modified Otsu method automatically selects initial threshold values using an iterative approach. After segmentation, features are extracted from the segmented results. An SVM classifier then categorizes the ovarian image as normal, cystic, or polycystic. Experimental results demonstrate that the proposed methods Follicle Identification Rate is 96.3% and the False Acceptance Rate is 2%, which significantly improves classification accuracy, highlighting its potential advantages for clinical application. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024.
Multimedia Tools and Applications;Volume;84;Issue;27;pp.32643-32669
https://doi.org/10.1007/s11042-024-20370-0 https://www.scopus.com/pages/publications/85212391699?origin=resultslist
Saranya R., Assistant Professor, Department of Computer Science with Data Analytics, PSG College of Arts & Science, Tamil Nadu, Coimbatore, India; Sridevi R., Associate Professor, Department of Computer Science, CHRIST University, Karnataka, Bangalore, India
Lung cancer detection and classification with optimal feature selection and two-fold-deep-learning-classifiers
CT images; DTO; Lung cancer detection; Manhattan Distance-based-GLCM; Optimized U-NETS; M-CNN
The respiratory system is undoubtedly hampered by lung disorders. Also, one of the important reasons for death among people all around the world has been lung cancer. Early discovery can advance human survival probabilities. As a result, a unique ensemble-deep-learning paradigm for lung cancer detection and classification is established in the present research effort. The projected model includes five major phases: (a) image augmentation, (b) pre-processing, (c) segmentation, (d) feature extraction, (e) feature selection, and (f) lung cancer detection and classification, respectively. The collected raw CT images are augmentation with SMOTE. The augmented images are pre-processed via Median Filtering (for noise removal) and Contrast-limited adaptive histogram equalization (CLAHE) (for image contrast enhancement). Subsequently, from the pre-processed data, the ROI is identified via optimized U-NETS. The activation function (hyper-parameter) of U-NETS is optimized via a new hybrid optimization model-Digging Tunaswarm Optimizer (DTO). This DTO is the conceptual amalgamation of two standard meta-heuristic optimization models, namely Honey Badger Algorithm (HBA) and Tuna Swarm Optimization (TSO) models, respectively. Then, from the selected ROI area, the features like texture features (Manhattan Distance-based-GLCM, GLRM), Color features (Color Histogram), and Shape features (Moments, Area, Perimeter) are extracted. Among the extracted features, the optimal features are selected using DTO. This optimal feature selection reduces the computational complexity of the projected model. Finally, using these extracted optimal features, the two-fold-deep-learning-classifier framework is trained. This two-fold-deep-learning-classifiers framework encapsulates the Bidirectional long-short term memory (Bidirectional LSTM) and the Recurrent Neural Network (RNN) and the Modified Convolutional Neural Network (M-CNN). In the first phase, the Bi-LSTM and RNN are clamped, and they are trained with the selected optimal factors. The outcome from Bi-LSTM and also RNN was fed as input to M-CNN. Final detected findings based on the existence or absence of lung cancer are acquired from the M-CNN, whose loss function has been modified with RMSE. Finally, a comparative evaluation is undergone to validate the efficiency of the projected model. The proposed model has a higher overall accuracy (92.4%) detecting modelling accuracy (96.3%) and classification accuracy (92.4%) compared to other models such as HBA, TSO, CNN, 3D CenterNet, and TSCNN. The use of a two-fold deep learning framework is responsible for these improvements, and the model also has lower failure rates (FPR and FNR) in detecting lung cancer. It is suggested that the proposed approach is effective in early-stage lung cancer detection. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2025.
Multimedia Tools and Applications;Volume;84;Issue;37;pp.46021-46063
https://doi.org/10.1007/s11042-025-20947-3 https://www.scopus.com/pages/publications/105008376695?origin=resultslist
Babu Kumar S., Assistant Professor, Department of AI, ML & DS, CHRIST University, Karnataka, Bangalore, India; Vinoth Kumar M., Associate Professor, Department of Information Science and Engineering, RV Institute of Technology and Management, Karnataka, Bangalore, India
Whispered speech emotion recognition with gender detection using hybridopti-gendernet
AHBN; Emotion recognition; Gender detection; HybridOpti-GenderNet; RBOA; Whispered speech
The Whispered Speech Emotion Recognition (SER) presents special challenges because it does not involve the vibration of vocal folds and less acoustic information, which makes it more difficult to identify the nuances of emotions and gender-related peculiarities than in normal speech. The research presents a new system, HybridOpti-GenderNet, of concurrent whispered speech emotion and gender recognition. It is a framework of six stages are data collection, pre-processing, feature extraction, feature selection, gender detection, and emotion recognition (ER). A Red Butterfly Optimization Algorithm (RBOA), which uses Butterfly Optimization Algorithm (BOA) and Red Kite Optimization Algorithm (ROA) by adjusting the weight to achieve optimal feature selection, is proposed to achieve a better balance between exploration and exploitation. Gender identification is carried out with the proposed HybridOpti-GenderNet, a new hybridization of Bi-LSTM and DCNN, and ER is accomplished with the help of the Attention-Enhanced Hybrid Belief Network (AHBN) that incorporates Deep Belief Network (DBN), Feedforward Neural Network (FNN) & a tailor-made attention mechanism to detect delicate emotional signals. The innovativeness of the given work is that the gender-informed recognition is combined with a high-level optimization and a hybrid deep learning pipeline that enhances the robustness of the analysis of whispered speech significantly. The system was tested in Python and tested on the GeWEC and EMO-DB data, showing superior performance in cases of privacy preservation, noisy conditions, and real-life human-computer interaction. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2026.
Mohanty, Aniruddha; Cherukuri, Ravindranath Chowdary
Multimedia Tools and Applications;Volume;85;Issue;4;Article No.;318;
https://doi.org/10.1007/s11042-026-21463-8 https://www.scopus.com/pages/publications/105035254935?origin=resultslist
Mohanty A., Department of Computer Science and Engineering, CHRIST (Deemed to be University), Bangalore, 560074, India; Cherukuri R.C., Department of Computer Science and Engineering, CHRIST (Deemed to be University), Bangalore, 560074, India
Enhanced image encryption using fractional-order chaotic systems and neural network-based optimization for secure multimedia applications
Fractional-order chaotic systems; Image encryption; Logistic map; Neural network optimization
The rapid expansion of multimedia data in fields like healthcare and finance necessitates robust image encryption to protect sensitive content. Conventional chaotic encryption, based on integer-order systems, is hindered by restricted key spaces (e.g., and suboptimal parameter choices, exposing vulnerabilities. This work introduces an innovative encryption method that merges a fractional-order chaotic Logistic map with neural network optimization to overcome these shortcomings and enhance security. Utilizing the Grunwald-Letnikov derivative, the fractional-order Logistic map produces a complex, unpredictable sequence for encryption. A feedforward neural network fine-tunes parameters (,), elevating the Lyapunov exponent from 0.5032 to 0.6540, signifying heightened chaos. This integration harnesses fractional-order memory effects and neural network adaptability, surpassing traditional integer-order encryption constraints. The method achieves a key space of, entropy of 7.9962, and horizontal correlation of 0.0028. Parameter sensitivity tests show significant output variation with minor changes. Security analysis yields NPCR at 99.60% and UACI at 33.45%. Neural network training achieves a low mean squared error of 0.0032912 by epoch 100, with high correlation. Encryption of 256256 images in 0.21 seconds and 720p video at 41.67 fps (0.024 s/frame) supports real-time applications. By combining fractional-order chaos with machine learning, this approach delivers superior image encryption, addressing integer-order system limitations. It provides a scalable framework for secure multimedia communications. Future efforts will extend the technique to color images and video, incorporating advanced machine learning for greater resilience. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2026.
P, Bhuvaneswari; V, Thirunavukkarasu; J, Loveline Zeema; NV, Poornima; Karnan, Lokanayaki
Multimedia Tools and Applications;Volume;85;Issue;6;Article No.;534;
https://doi.org/10.1007/s11042-026-21701-z https://www.scopus.com/pages/publications/105039884419?origin=resultslist
P B., Department of Machine Learning, Yazhli Global Multidisciplinary Research Organization(YGMRO), Tamilnadu, Tirupur, India; V T., Department of Computer Science, Christ (Deemed to be University), Karnataka, Bengaluru, India; J L.Z., Department of Computer Science, Christ (Deemed to be University), Karnataka, Bengaluru, India; NV P., Symbiosis Centre for Management Studies, Symbiosis International (Deemed University), Karnataka, Bengaluru, India; Karnan L., School of Computer Science and Engineering, RV University, Karnataka, Bengaluru, India
Dual ion-imprinted chitosan-stabilized platinum nanoparticles for simultaneous electrochemical detection of Cd2? and Pb2? in water samples
Cd2? detection; Chitosan-stabilized PtNPs; Differential pulse anodic stripping voltammetry; Dual ion-imprinted sensor; Heavy metal sensing; Pb2? detection
The development of highly selective and ultrasensitive electrochemical sensors for trace-level heavy metal monitoring remains a critical challenge in environmental analysis. In this work, a novel dual ion-imprinted, chitosan-stabilized platinum nanoparticle (PtNP)modified glassy carbon electrode (GCE) is reported for the simultaneous electrochemical detection of Cd2? and Pb2? in aqueous media. The synthesized PtNPs provide a large electroactive surface area and are uniformly stabilized within a chitosan matrix enriched with oxygen- and nitrogen-containing functional groups, which act as selective coordination sites for target metal ions. The incorporation of dual ion-imprinting generates specific recognition cavities that promote selective adsorption of Cd2? and Pb2? through electrostatic and coordination interactions, leading to significantly enhanced sensitivity and selectivity. Under optimized conditions, the sensor exhibits wide linear detection ranges of 44.04pM0.18nM for Pb2? and 79.4pM0.18nM for Cd2?, with remarkably low detection limits of 13.2pM and 23.83pM, respectively. The proposed sensing platform demonstrates excellent anti-interference capability and reliable performance in real water samples, confirming its applicability for practical environmental monitoring. This study highlights the synergistic effect of dual ion-imprinting and chitosan-stabilized PtNPs, offering a robust and efficient strategy for multi-ion electrochemical sensing of toxic heavy metals. The Author(s), under exclusive licence to Springer Nature B.V. 2026.
Journal of Nanoparticle Research;Volume;28;Issue;6;Article No.;144;
Springer Science and Business Media B.V.
https://doi.org/10.1007/s11051-026-06669-z https://www.scopus.com/pages/publications/105039891649?origin=resultslist
Ann Maria C.G., Department of Chemistry, CHRIST(Deemed to Be University), Bengaluru, India; Nidhin M., Department of Chemistry, CHRIST(Deemed to Be University), Bengaluru, India
Spatial variations of landslide severity with respect to meteorological and soil related factors
GWR; Landslide; Meteorological factors; Soil variables; Spatial heterogeneity
Landslides, a prevalent natural disaster, wreak havoc on both human lives and vital infrastructure, making them a significant global concern. Their devastating impact is immeasurable, necessitating proactive measures to minimize their occurrence. The ability to accurately forecast the severity of a landslide, including its potential fatality rate and the scale of destruction it may cause, holds tremendous potential for prevention and mitigation to reduce the risk and the damage caused by a landslide to infrastructure and life. In this study, the spatial variability in severity of landslides (in terms of mortality rates) and its dependence on various meteorological, geographical and soil composition has been attempted to be established. To do this, Ordinary Least Squares (global) and various Geographically Weighted (local) models have been employed to observe the varying relation between mortality rates and its various causative factors. Existence of geographical heterogeneity in the relationships is also investigated. The spatial pattern of landslide mortality and its associations with various causative variables in the South Asian Region are investigated and analysed. Through this, insights into targeting of prevention and mitigation measures for landslides based on a given location can be obtained by studying the various forms of heterogeneous spatial associations observed. The outcomes highlight that the local models in the form of Gaussian GWR and Poisson GWR outperform their global counterparts by a huge margin with better R2 and Adj R2 values. In comparison with Poisson GWR and Gaussian GWR, it is seen that Poisson GWR outperforms Gaussian GWR in terms of Mean Absolute Error, Mean Squared Error and Corrected Akaike Information Criterion. Furthermore, several intriguing local relationships patterns are also noted. The Author(s), under exclusive licence to Springer Nature B.V. 2024.
Dutta, Kunal; Poddar, Arkaprabha; Middya, Asif Iqbal; Roy, Sarbani
Natural Hazards;Volume;121;Issue;3;Article No.;e23247;pp.3267-3291
https://doi.org/10.1007/s11069-024-06930-5 https://www.scopus.com/pages/publications/85204785694?origin=resultslist
Dutta K., Department of Statistics and Data Science, Christ (Deemed to be) University, Bengaluru, India; Poddar A., Department of Statistics and Data Science, Christ (Deemed to be) University, Bengaluru, India; Middya A.I., Department of Computer Science and Engineering, Jadavpur University, Kolkata, India; Roy S., Department of Computer Science and Engineering, Jadavpur University, Kolkata, India
Control of chaos and intermittent periodic motions in Rayleigh-Bard convection using a feedback controller
Chaos; Feedback controller; Meclaurin series; Periodic motion; Rayleigh-Bard convection
Control of regular convective motion, chaos and periodic motion in the Rayleigh-Bard system is studied by considering a feedback control mechanism that considers the dependence of the heating (cooling) of the two boundary plates on one another. This set up ensures that the different flow regimes (convective, chaotic and periodic) in the system have no mechanical interference and the control remains an external mechanism. The rheostatic influence of feedback control on these flows is demonstrated by investigating in detail the critical Rayleigh number in the case of regular convective motion and the Hopf-Rayleigh number in the case of chaotic motion. For mild coupling between lower and upper boundary temperatures, periodic motions are intermittently observed in an otherwise chaotic regime at times when the system arrives at a situation (fuelling zone) wherein it needs to conserve energy in order to sustain chaos at subsequent times. For strong coupling between the boundary temperatures, an interesting situation arises wherein chaos makes a delayed and brief appearance and gives way to a prolonged spell of periodic motion. Features of the classical Rayleigh-Bard system are retained but each regime makes a delayed appearance. The Author(s), under exclusive licence to Springer Nature B.V. 2024.
Kanchana, C.; Siddheshwar, P.G.; Laroze, D.
Nonlinear Dynamics;Volume;113;Issue;7;pp.7297-7313
https://doi.org/10.1007/s11071-024-10494-1 https://www.scopus.com/pages/publications/105001070319?origin=resultslist
Kanchana C., Instituto de Alta Investigaci, Universidad de Tarapac Casilla 7 D, Arica, 1000000, Chile; Siddheshwar P.G., Centre for Mathematical Needs, CHRIST (Deemed to be University), Hosur Road, Bengaluru, 560029, India; Laroze D., Instituto de Alta Investigaci, Universidad de Tarapac Casilla 7 D, Arica, 1000000, Chile
Diffusive instability, patterns and limit cycles in a slow-fast generalized SamardzijaGreller model: a multiscale approach
Caputo fractional derivative; Chaos; Fractional Hopf bifurcation; Pattern formation; SamardzijaGreller model
The SamardzijaGreller model is an extension of the classical LotkaVolterra predatorprey system, and this paper investigates the multiscale dynamics in a modified SamardzijaGreller model to take into account the slower timescales in predator reactions rather than prey. We present a comprehensive local stability analysis, pattern formation through diffusive instability and fractional Hopf bifurcations. The analysis of the spatio-temporal model reveals the effects of diffusion coefficients and parameter variations on the dynamical behavior of the slow-fast system. By analyzing the systems response to changes in the self-diffusion rate of the prey (dX), the intra-species competition rate of the first predator (d1) and the interaction parameter a, we observe chaotic patterns for small values of a, particularly when the prey exhibits strong diffusion. Increases in a lead to the emergence of regular, periodic patterns that are homogeneous in space. We discuss in detail how fractional-order models create memory effects that inhibit chaotic transitions, potentially being delayed or avoided in the temporal model. The study shows clear differences in the dynamical regimes between the integer-order and the fractional-order models. The latter model gives more significance to the stabilization effect of the fractional-order derivative on ecological systems and improves our understanding of predatorprey interactions under different parameter settings. Findings clarify the potential to derive ecological stability from emergent patterns and transition into a better understanding of complex ecological processes. The Author(s), under exclusive licence to Springer Nature B.V. 2025.
Chakraborty, Arkaprovo; Mukherjee, Nayana; Veeresha, P.
Nonlinear Dynamics;Volume;113;Issue;14;Article No.;33127;pp.18037-18058
https://doi.org/10.1007/s11071-025-11022-5 https://www.scopus.com/pages/publications/105003033683?origin=resultslist
Chakraborty A., Department of Mathematics, CHRIST (Deemed to be University), Bengaluru, 560029, India; Mukherjee N., Department of Mathematics, Mahindra University, Hyderabad, 500043, India; Veeresha P., Department of Mathematics, CHRIST (Deemed to be University), Bengaluru, 560029, India
Spotlighting recruitments: is AI dominating human resource practices? Qualitative research using NVIVO
Artificial intelligence; Human resource management; NVivo; Recruitment; Technology
Technology enriches and empowers organizations, making them more competitive and profitable. Any organization function is now technology-driven, helping to make faster and better decisions. Human resource management practices are also automated nowadays. Artificial Intelligence (AI) has gained enough importance in the recruitment process. Most of the literature emphasizes the use of technology and AI in establishing an effective and efficient recruitment process; however, the dominance of AI arouses the need to cast light upon the imbalance created after Al implementation. This study focuses on identifying the adverse impact of automated recruitment processes, which, due to a lack of human consciousness and intelligence, may sometimes not find the right candidate for the vacant position. Thus, a qualitative study was conducted to check the need for a balance of collaboration between humans and AI in recruitment. Primary data was collected through structured interviews with 21 HR professionals of IT companies in India implementing AI in their recruitment process. The findings highlight the positive impact of AI tools on recruitment efficiency but raise concerns about the loss of human connection, the potential misuse of AI, and the need for balanced decision-making in the hiring process. Based on the study's findings, it is recommended that a framework that combines humans and AI can be created. This study enables organizations to develop a customized recruitment process aligned with their vision, optimizing the use of AI and human intelligence to improve procedures and understand the impact of AI on hiring. The Author(s), under exclusive licence to Springer Nature B.V. 2025.
Pandey, Pallavi; Sharma, Avichal; Jeswani, Saket; Sharma, Deepti; Gupta, Ashulekha
Quality and Quantity;Volume;59;Issue;Suppl 2;Article No.;100899;pp.1209-1228
https://doi.org/10.1007/s11135-025-02062-5 https://www.scopus.com/pages/publications/85217185504?origin=resultslist
Pandey P., Department of Commerce, CHRIST (Deemed to Be University), Pune-Lavasa Campus, Lavasa, India; Sharma A., Department of Data Sciences, CHRIST (Deemed to Be University), Pune-Lavasa Campus, Lavasa, India; Jeswani S., Faculty of Commerce & Management, Kalinga University, Raipur, Chhattisgarh, India; Sharma D., OP Jindal University, Raigarh, Chhattisgarh, India; Gupta A., Department of Management Studies, Graphic Era (Deemed to Be University), Uttarakhand, Dehradun, India
Reliability estimation of multicomponent stressstrength system with non-identical strength components based on generalized inverted exponential distribution
Bayesian estimation; Generalized inverted exponential distribution; Maximum likelihood estimation; Monte Carlo simulation; Multicomponent stress strength reliability
This research article estimates the reliability of s-out-of-k multicomponent systems subjected to common stress, where the strength components are non-identical and independently distributed. In practical scenarios, it is often unrealistic to assume that all strength components of a system are identical. To address this problem, we estimate the reliability of multicomponent stress strength (MSS) systems under the assumption of non-identical strength components and a common stress component, following independent generalized inverted exponential distributions. The estimation of MSS reliability is performed using both classical and Bayesian approaches. In the classical framework, the maximum likelihood estimation method is employed for point estimation, while asymptotic confidence intervals are constructed for interval estimation. In the Bayesian framework, point and interval estimates are obtained using TierneyKadanes approximation and Markov chain Monte Carlo techniques under an asymmetric loss function, as the Bayes estimator does not have a closed-form expression. A comprehensive numerical simulation study is conducted to compare the performance of the various estimators developed. Finally, the proposed methodologies are illustrated using a real-life dataset, showcasing their practical applicability and effectiveness. From the numerical studies, it is found that the MSEs for the classical and Bayes estimates are less than 0.010, and the coverage probabilities of the interval estimates attain their nominal level of significance, i.e. 95% in most of the cases. The Author(s), under exclusive licence to Springer Nature B.V. 2025.
Kumari, Maya; Garg, Renu; Sahoo, Ranjan Kumar; Kumari, Anita
https://doi.org/10.1007/s11135-025-02260-1 https://www.scopus.com/pages/publications/105012772634?origin=resultslist
Kumari M., Department of Statistics, Central University of Haryana, Mahendergarh, 123031, India; Garg R., Department of Statistics, Ramanujan College, Delhi, 110019, India; Sahoo R.K., Department of Statistics, Central University of Haryana, Mahendergarh, 123031, India; Kumari A., Department of Statistics and Data Science, Christ University, Bengaluru, India
Effect of different impact velocities on mechano-luminescence of natural calcite for mechanical sensors
Calcite; Impact velocity; Mechanical sensor; Mechanoluminescence
This paper studies the mechanoluminescence (ML) behavior of natural calcite under varying impact velocities to assess its potential use in passive mechanical sensing. Calcite samples obtained from Byrnihat, Meghalaya (2603?03.8?N 9152?11.0?E), were analyzed using X?ray diffraction, field emission scanning electron microscopy, energy-dispersive X?ray spectroscopy, and Fourier-transform infrared spectroscopy. The analysis confirms the formation of the nanocrystalline hexagonal phase with minor impurities that affect its luminescent properties. When subjected to the mechanical impact, the calcite consistently produces asharp ML peak around 17?ms, regardless of the impact speed. The emitted light intensity shows alinear dependence on the impact velocity, suggesting areliable correlation between the mechanical input and optical response. The emission decay follows afirst-order exponential pattern, supporting its usefulness for identifying short-duration force events. Aplot of time against the logarithm of intensity displays aclear negative slope, supporting this kinetic model. These research findings highlight the potential of natural calcite as areliable and environmentally friendly material for mechanical sensor applications. The Author(s), under exclusive licence to Springer Nature Switzerland AG 2025.
Peng, Wei; Bani, Faithfulstar K; Saji, Janita; Lamare, Rocky Maximillian Pohlong; Hu, Guoqing; Dubey, Vikas
Russian Physics Journal;Volume;68;Issue;10;pp.1548-1557
https://doi.org/10.1007/s11182-025-03591-0 https://www.scopus.com/pages/publications/105024878715?origin=resultslist
Peng W., School of Mechanical and Automotive Engineering, South China University of Technology, Guangzhou, China; Bani F.K., Department of Physics, North-Eastern Hill University, Meghalaya, Shillong, India; Saji J., Department of Sciences and Humanities, School of Engineering and Technology, CHRIST University, Bengaluru, India; Lamare R.M.P., Department of Physics, North-Eastern Hill University, Meghalaya, Shillong, India; Hu G., Department of Engineering and Technology, Xicheng District, Beijing, China; Dubey V., Department of Physics, North-Eastern Hill University, Meghalaya, Shillong, India
Translation and Validation of the Malayalam Version of the Subjective Happiness Scale
Malayalam; Measurement; Subjective happiness scale; Validity; Well-being
The subjective happiness scale (SHS) is a brief instrument used to measure global subjective happiness that has been translated from its original English to many other languages. To date, there is no reported translation of this scale into Malayalam, a language spoken by over 32 million people especially in the southern state of Kerala, India. In the present study, 656 community-dwelling older adults participating in the Kerala Einstein study (KES) completed the Malayalam version of the SHS. The Malayalam version demonstrated high internal consistency and good convergent validity, as assessed by comparison to measures of depression and anxiety. We also used factor analysis to determine that the Malayalam version of the SHS has a unidimensional structure, akin to the original English as well as other language adaptations. Our study adds to the repertoire of tools to measure happiness in non-English-speaking populations, enabling future research to explore the foundations of well-being across diverse cultures. The Author(s) 2024.
Cotton, Kelly; Sathyan, Sanish; Jacob, Soumya; Shaji, K.S.; Ayers, Emmeline; Adhikari, Dristi; Sigamani, Alben; Pradeep Kumar, V.G.; Verghese, Joe
Social Indicators Research;Volume;176;Issue;1;Article No.;e49933;pp.245-255
All Open Access; Green Open Access; Hybrid Gold Open Access
https://doi.org/10.1007/s11205-024-03448-y https://www.scopus.com/pages/publications/86000427255?origin=resultslist
Cotton K., Department of Neurology, Albert Einstein College of Medicine, 1225 Morris Park Avenue, Bronx, 10461, NY, United States; Sathyan S., Department of Neurology, Albert Einstein College of Medicine, 1225 Morris Park Avenue, Bronx, 10461, NY, United States; Jacob S., Christ University, Bengaluru, India; Shaji K.S., Kerala University of Health Sciences, Kerala, Thrissur, India; Ayers E., Department of Neurology, Albert Einstein College of Medicine, 1225 Morris Park Avenue, Bronx, 10461, NY, United States; Adhikari D., Department of Neurology, Albert Einstein College of Medicine, 1225 Morris Park Avenue, Bronx, 10461, NY, United States; Sigamani A., Carmel Research Consultancy Pvt Ltd, Bengaluru, India; Pradeep Kumar V.G., Institute of Neurosciences, Baby Memorial Hospital, Kozhikode, India; Verghese J., Department of Neurology, Albert Einstein College of Medicine, 1225 Morris Park Avenue, Bronx, 10461, NY, United States, Department of Medicine, Albert Einstein College of Medicine, Bronx, NY, United States
Development and Validation of the Brief Financial Resilience Scale
Economic wellbeing; Financial resilience; Financial security; Financial vulnerability; Resilience assessment; Scale development
Financial resilience refers to the ability to withstand and recover from financial adversity. Despite its increasing relevance, there is a notable lack of well-constructed and psychometrically validated tools to measure this construct. This study aimed to develop and validate the Brief Financial Resilience Scale (BFRS), based on Salignac et al. (Social Indicators Research, 145(1), 1738, 2019) multidimensional framework. The process involved content validation using Lawshes method, followed by item analysis, exploratory factor analysis, and confirmatory factor analysis using data from a community sample of 433 Indian millennials. The results support a two-dimensional structure: (a) financial resources and access, and (b) financial knowledge and behavior. The final 10-item BFRS demonstrated acceptable reliability (Cronbachs alpha = 0.885) and construct validity. The scale would be useful for policymakers, practitioners, and researchers in identifying vulnerabilities and design targeted interventions within diverse socioeconomic contexts. The Author(s), under exclusive licence to Springer Nature B.V. 2025.
Rayampatt, Manjusha C.; Rajan, Santhosh Kareepadath
Social Indicators Research;Volume;179;Issue;3;pp.1417-1430
https://doi.org/10.1007/s11205-025-03673-z https://www.scopus.com/pages/publications/105010775911?origin=resultslist
Rayampatt M.C., School of Psychological Sciences, Christ University, Bengaluru, India; Rajan S.K., School of Psychological Sciences, Christ University, Bengaluru, India
A Study on the Stability of DarcyBrinkmanBard Convection in a Binary Fluid-Saturated Porous Medium: RigidRigid Boundaries
Binary fluid; Galerkin method; Lewis number; Natural convection; Rayleigh number; Rigid-rigid boundaries
The linear stability analysis of DarcyBrinkmanBard convection (DBBC) in a binary fluid-saturated porous layer is studied numerically using n term Galerkin approach for rigidrigid, isothermal boundaries. The occupied binary fluid and porous medium are assumed to be in thermal non-equilibrium. Thus, two energy equations are used for each phase. The critical values of the DarcyRayleigh and wave numbers for theonset of convectionare obtained by considering ten terms in the Galerkin solution. The effect of the five parameters of the model, namely the Darcy number, Da, the modified ratio of thermal conductivity ?, theLewis number Le, theseparation ratio coefficient, ?, and the inter-phase heat transfer coefficient, H, on the stability of the system is discussed in detail and presented with the aid of plots and tables. The onset of convection in a binary fluid-saturated porous medium is delayed for realistic boundary conditions compared with ideal boundary conditions (stress-free, isothermal boundary conditions). Increasing the values of theDarcy number, inter-phase heat transfer coefficient, and the separation ratio coefficient stabilizes DBBC. In contrast, the thermal conductivity ratioand Lewis number aredestabilize the system. Furthermore, convective cell size remains unaltered with increasing ?. Convection is delayed in thepure fluid medium compared to thebinary fluid medium. Local thermal non-equilibrium ceases for small and large inter-phase heat transfer coefficient values. The Author(s), under exclusive licence to Springer Nature B.V. 2025.
Transport in Porous Media;Volume;152;Issue;7;Article No.;49;
https://doi.org/10.1007/s11242-025-02187-z https://www.scopus.com/pages/publications/105007519233?origin=resultslist
Siddabasappa C., Department of Sciences and Humanities, CHRIST University, Karnataka, Bangalore, 560074, India; Babitha, Department of Mathematics, CHRIST University, Karnataka, Bangalore, 560029, India; Jeevan B.S., Department of Mathematics and Statistics, M S Ramaiah University of Applied Sciences, Karnataka, Bangalore, 560058, India
The Effect of Viscous Dissipation on the DarcyBard Problem: Weakly Nonlinear Analysis and Strongly Nonlinear Computations
Darcy-Benard; Porous; Stability; Strongly nonlinear; Viscous dissipation; Weakly nonlinear
We consider the effect of viscous dissipation on the onset and nonlinear development of two-dimensional convection in a unit enclosure heated from below. First, we show that the linear theory is unchanged from that which arises when viscous dissipation is absent. Second, a weakly nonlinear analysis shows that convection becomes weaker with increasing values of Ge~, a modified Gebhart number. In addition, the rate of heat transfer at the lower and upper sufaces differ from one another. Third, nonlinear convection is found to lose both up/down and left/right symmetry as both Ge~ and Ra (the DarcyRayleigh number) increase. It is also found that once viscous dissipation increases in strength to unphysically large amounts, then the maximum temperature migrates from the lower boundary to the interior of the enclosure. The Author(s) 2025.
Transport in Porous Media;Volume;152;Issue;12;Article No.;111;
All Open Access; Hybrid Gold Open Access
https://doi.org/10.1007/s11242-025-02229-6 https://www.scopus.com/pages/publications/105021232918?origin=resultslist
Rees D.A.S., Department of Mechanical Engineering, University of Bath, Bath, BA2 7AY, United Kingdom; Siddheshwar P.G., Department of Mathematics, Centre for Mathematical Needs, Christ University, Bengaluru, 560 029, India
Pt Nanospheres Decorated Graphene-?-CD Modified Pencil Graphite Electrode for the Electrochemical Determination of Vitamin B6
Electro-catalytic oxidation; Graphene; Pencil graphite electrode; Vitamin B6; ?-CD
An electrochemical sensor for Vitamin B6 determination has been prepared by the electrochemical deposition of Pt nanospheres on graphene-?-CD coated Pencil Graphite Electrode (PGE). Cyclic voltammetric (CV) and electrochemical impedance spectroscopic (EIS) studies were employed to explore the electrochemical properties of the modified electrode. The physicochemical properties of the modified electrodes were characterized by X-ray photoelectron spectroscopy (XPS), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and optical profilometric studies. The experimental conditions such as effect of scan rate, concentration and pH were optimized. The linear dynamic range for the determination of Vitamin B6 was found to be 5nM to 205nM. The low level of detection limit (1.2nM) implies the high sensitivity of the process. The suggested method was effectively employed for the electrocatalytic evaluation of Vitamin B6 in different juice samples. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2022.
Rison, Sherin; Mathew, Agnus T.; George, Louis; Maiyalagan, T.; Hegde, Gurumurthy; Varghese, Anitha
Topics in Catalysis;Volume;68;Issue;13;pp.1338-1348
https://doi.org/10.1007/s11244-021-01559-1 https://www.scopus.com/pages/publications/85123199355?origin=resultslist
Rison S., Christ Academy Institute For Advanced Studies, Christ Nagar, Bangalore, 560083, India, Department of Chemistry, CHRIST (Deemed To Be University), Bangalore, 560029, India; Mathew A.T., Department of Chemistry, CHRIST (Deemed To Be University), Bangalore, 560029, India; George L., Department of Chemistry, CHRIST (Deemed To Be University), Bangalore, 560029, India; Maiyalagan T., SRM Institute of Science and Technology, Kattankulathur, 603203, India; Hegde G., Department of Chemistry, CHRIST (Deemed To Be University), Bangalore, 560029, India, Centre for Advanced Research and Development (CARD), CHRIST (Deemed To Be) University, Bangalore, 560029, India; Varghese A., Department of Chemistry, CHRIST (Deemed To Be University), Bangalore, 560029, India
Visible Light Mediated Organophotoredox-Catalyzed One-Pot Domino Synthesis of Novel 6,7 Disubstituted 1H-Pyrroles
6,7 disubstituted 1H-pyrrole; Ethanol; Fluorescein; Four-component reaction; Organophotocatalyst; Visible light
The development of environmentally benign protocols to synthesize novel N-heterocycles is vital in the field of synthetic organic chemistry. We herein report a successful one-pot domino synthesis of novel 6,7 disubstituted 1H-pyrroles using substituted phenacyl bromide, barbituric acid/Meldrums acid, aromatic amines catalysed by 5mol% Fluorescein in presence of visible light. This procedure is a useful and adaptable method for the synthesis of pyrroles since it is compatible with a wide range of sensitive functional groups, does not require column chromatography purification. During the reaction, Fluorescein may catalyse the formation of enamine leading to amino alcohol which subsequently undergoes dehydration to give 6,7 disubstituted 1H-pyrroles. All the synthesized derivatives were obtained in 9095% yields and were characterized by 1H, 13C NMR and HRMS (ESI) analysis. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2022.
Govindaraju, Santhosh; Tabassum, Sumaiya
Topics in Catalysis;Volume;68;Issue;13;pp.1596-1608
https://doi.org/10.1007/s11244-022-01580-y https://www.scopus.com/pages/publications/85124335550?origin=resultslist
Govindaraju S., Department of Sciences and Humanities, School of Engineering and Technology, CHRIST (Deemed To Be University), Kumbalagodu, Mysore Road, Bengaluru, 560074, India; Tabassum S., Department of Chemistry, Surana College, South End Road, Basavanagudi, Bengaluru, 560004, India
(Mes-Acr-Me)+ClO4 Catalyzed Visible Light-Supported, One-Pot Green Synthesis of 1,8-Naphthyridine-3-Carbonitriles
1,8-Naphthyridines; 9-Mesityl-10-methylacridinium perchlorate; Blue LED; Excellent yield; Multicomponent reaction
Abstract: A novel, four-component one-pot green synthesis of biologically active 1,8-naphthyridines by a reaction of diverse aromatic aldehyde, malononitrile, 4-hydroxy substituted 1,6-dimethylpyridin-2(1H)-one, corresponding aniline in EtOH catalyzed by 9-Mesityl-10-methylacridinium perchlorate [(Mes-Acr-Me)+ClO4] under visible light generated from a 24W Blue LED wavelength 450460nm at 26C is reported. In contrast with the reported procedure, our methodology is diverse, versatile and has several favourable factors such as metal-free, excellent yields, shorter reaction durations, chromatography free and straightforward extraction process. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2022.
Tabassum, Sumaiya; Govindaraju, Santhosh; Kendrekar, Pravin
Topics in Catalysis;Volume;68;Issue;13;pp.1440-1448
https://doi.org/10.1007/s11244-022-01583-9 https://www.scopus.com/pages/publications/85124739905?origin=resultslist
Tabassum S., Department of Chemistry, Surana College, South End Road, Basavanagudi, Bengaluru, 560004, India; Govindaraju S., Department of Sciences and Humanities, School of Engineering and Technology, CHRIST (Deemed to be University), Kumbalagodu, Mysore Road, Bengaluru, 560074, India; Kendrekar P., Lipid Nanostructures Laboratory, Centre for Smart Materials, School of Natural Sciences, University of Central Lancashire, Preston, PR1 2HE, United Kingdom
White LED Light-Mediated Eosin Y-Photocatalyzed One-Pot Synthesis of Novel 1,2,4-Triazol-3-Amines By Sequential Addition
1,2,4-Triazol-3-amine; Eosin Y; Four-component synthesis; Metal-free; Multicomponent reaction; Photocatalyst; White LED
Abstract: A facile and proficient, eco-friendly multicomponent synthesis of 12 novel biologically essential 1,2,4-triazol-3-amines via the sequential addition of substituted phenacyl bromide, aromatic aldehyde, hydrazinecarbothioamide, and urea under white LED with eosin Y as a photocatalyst has been developed. The intrinsic advantages are methodology is cost-effective, non-toxic, generates a high yield of product, is column chromatography free and does not need the use of a specific instrument. Surprisingly, our methodology uses moderate conditions and can count the tolerance of a wide variety of electron-donating and electron-withdrawing groups. The analysis and early conclusions give more value and context for the future development of organic synthesis using photocatalysts. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2022.
Tabassum, Sumaiya; Govindaraju, Santhosh
Topics in Catalysis;Volume;68;Issue;13;pp.1523-1533
https://doi.org/10.1007/s11244-022-01590-w https://www.scopus.com/pages/publications/85124333009?origin=resultslist
Tabassum S., Department of Chemistry, Surana College, South End Road, Basavanagudi, Bengaluru, 560004, India; Govindaraju S., Department of Sciences and Humanities, School of Engineering and Technology, CHRIST (Deemed to be University), Kumbalagodu, Mysore Road, Bengaluru, 560074, India