Bharath University

Abstract This study presents a comprehensive SCAPS-1D simulation of a lead-free double-perovskite solar cell based on 
NaZn₀.₇Ag₀.₃Br₃ as the absorber layer. Various electron transport layers (CdZnS, MZO, Nb₂O₅, and SnS₂) were 
systematically evaluated to optimize device performance. Among the investigated configurations, the 
FTO/SnS₂/NaZn₀.₇Ag₀.₃Br₃/CuAlO₂/Pt structure exhibited superior photovoltaic characteristics due to improved 
band alignment and reduced recombination losses. Under ideal radiative-loss-free conditions (B = 0), a maximum 
power conversion efficiency (PCE) of 30.56% was obtained. However, after incorporating a realistic radiative 
recombination coefficient (B = 2.3 × 10⁻⁹ cm³/s), the optimized device achieved a PCE of 29.92%, with minimal 
variation in short-circuit current density and a moderate reduction in open-circuit voltage. The results confirm that 
the proposed lead-free perovskite configuration maintains strong photovoltaic performance under physically 
realistic recombination conditions, highlighting its potential for high-efficiency and environmentally benign solar 
cell applications.

Mosquito-borne diseases remain a global health threat, necessitating the development of ecofriendly alternatives to chemical insecticides. This study evaluated the larvicidal activity of Cyperus rotundus L. extracts and the isolated compound Charantagenin D against Aedes aegypti L., Anopheles stephensi Liston, and Culex quinquefasciatus Say. Four solvent extracts (n-hexane, chloroform, methanolic ethyl acetate, and aqueous) were tested at concentrations ranging from 10 to 40 ppm. The n-hexane extract exhibited the highest efficacy, causing 100% mortality in fourth instar larvae of all three mosquito species at 40 ppm. Statistical analysis revealed significant differences among extracts and mosquito species (P < 0.001), with Ae. aegypti showing the highest susceptibility. Bioassay-guided fractionation of the n-hexane extract yielded nine fractions, of which Fraction 8 showed strong larvicidal activity. Spectroscopic analysis identified Charantagenin D, a triterpene glycoside, as the active constituent. Charantagenin D achieved 100% mortality at 40 ppm and exhibited a median lethal concentration of 16.179 ppm and a 90% lethal concentration of 31.065 ppm for Cx. quinquefasciatus, with comparable effects on the other two species. These findings highlight the potential of Charantagenin D as a botanical larvicide and support the use of plant-derived compounds in sustainable mosquito control strategies.

Abstract Tobacco use remains a leading cause of preventable morbidity and mortality worldwide, with India facing a particularly high burden. Traditional tobacco cessation methods often encounter limitations, such as high relapse rates and a lack of user engagement. Virtual reality (VR) emerges as a novel, immersive tool that addresses these challenges by simulating real-world smoking scenarios, enabling users to build coping mechanisms, manage cravings, and experience the physiological impact of tobacco. VR enhances behavioural therapies, such as the 5A’s and 5R’s, through interactive exposure, education, and real-time feedback. It is especially effective for adolescents and tech-savvy users, offering personalised, scalable, and engaging interventions. By visualising the consequences of tobacco use and the benefits of quitting, VR motivates sustained behavioural change. As digital health becomes more integrated into public wellness programs, VR has the potential to revolutionise tobacco cessation strategies, making them more impactful and widely accessible.

Acute Lymphoblastic Leukemia (ALL) is the most prevalent form of childhood cancer, accounting for approximately 25% of all pediatric malignancies worldwide. Conventional diagnosis relies on a trained hematopathologist manually examining Giemsa-stained bone marrow smear slides, a process that is both time-consuming and inherently subjective, with inter-observer variability of up to 20% reported in clinical literature. This paper presents Marrow-Find, a fully integrated AI-powered web application designed to automate the classification, visual explanation, and quantification of leukemia cells from bone marrow microscopic images. The system employs a ResNet50 deep convolutional neural network, pre-trained on ImageNet and fine-tuned on the C-NMC 2019 and ALL-IDB benchmark datasets, to classify bone marrow cells into four clinically significant categories: Benign, Pre-B ALL, Pro-B ALL, and Early Pre-B ALL. The model achieves an overall test accuracy of 94.8% with a weighted F1-score of 0.954 and a Cohen's Kappa of 0.931. To address class imbalance, a Conditional Generative Adversarial Network (cGAN) generates realistic synthetic bone marrow cell images for minority classes. Gradient-weighted Class Activation Mapping (Grad-CAM) produces visual heatmap overlays on each prediction, enabling pathologists to verify the morphological features influencing the model's decision. A Watershed-based segmentation algorithm automatically delineates individual cell boundaries and counts blast cells per image. All five components are integrated into a Flask web application with secure user authentication, prediction history, PDF report generation with QR codes, and an AI chatbot, making specialist-level leukemia diagnostics accessible from any standard web browser.

Introduction: The present study aimed to investigate the phytochemical constituents of the ethanolic root extract of Tabernaemontana divaricata through qualitative screening and thin-layer chromatography (TLC) analysis. Materials and Methods: The root samples were subjected to maceration using ethanol, and the resulting extract was evaluated for the presence of secondary metabolites using standard qualitative tests. Preliminary TLC analysis was performed to determine the chemical profile of the extract, and the retention factor (Rf) values were recorded. Results: The qualitative screening revealed the prominent presence of alkaloids, tannins, and flavonoids in the ethanolic extract. TLC analysis confirmed the presence of distinct phytochemical bands, and the calculated Rf values indicated the separation and identification of bioactive components. Discussion: Natural products are bioactive chemical compounds derived from living organisms such as plants, fungi, animals, or microorganisms. These compounds are a rich source of pharmacologically active agents and have been extensively used in medicinal, nutritional, and industrial applications. Compared to synthetic compounds, which are chemically synthesized and structurally simpler, natural products often exhibit a broader spectrum of biological activity. Conclusion: The ethanolic root extract of T. divaricata demonstrated the presence of important phytoconstituents, highlighting its potential as a source of pharmacologically relevant natural products. Further isolation and characterization of these compounds are warranted.

Abstract Background: This study aimed to evaluate and compare NCD awareness and associated risk factors among adolescents in rural and urban schools of West Bengal. Subjects and Methods: A school-based, analytical study was conducted from March to August 2021 in selected schools across three districts of West Bengal using a multistage sampling technique. A total of 320 adolescents (160 urban, 160 rural) were selected using probability proportional to size and simple random sampling. Data were collected using a pre-tested, validated questionnaire and standardised physical measurements. Awareness was assessed using an 8-item Likert scale. Risk factors, including dietary habits, physical activity, body mass index, waist–hip ratio and blood pressure, were evaluated. Statistical analysis was done using SPSS v20. Results: Urban students showed higher awareness of NCDs, including hypertension (100% vs. 88.6%), diabetes and coronary heart disease ( P &lt; 0.001). Median knowledge scores were lower (better awareness) in urban students (10, interquartile range [IQR]: 8) than rural students (11, IQR: 7, P &lt; 0.001). Rural students had higher overweight/obesity prevalence (26.9% vs. 14.4%, P = 0.008) and extra salt intake (27.5% vs. 12.5%, P &lt; 0.001). Physical activity and fruit/vegetable intake were suboptimal in both groups. Conclusion: Urban students demonstrated better awareness, whereas rural adolescents showed a higher burden of modifiable risk factors. School-based programs, parental engagement and community surveillance are vital to prevent NCDs in adolescence.

Background: The Marginal mandibular nerve is a terminal branch of Facial nerve. The nerve runs close to the inferior margin of the mandible, superficial to the facial vessels and supplies the muscles of the lower lip. The proper knowledge on variations along the course of the nerve and its relations to facial vessels play a significant role in determining the success of any surgical intervention in that region. Materials and methods: This study is a cross-sectional study conducted in the department of anatomy of a private medical college in Tamil Nadu, India. Fifty facial halves from embalmed cadavers are utilised for this study. Descriptive statistics is used to analyse the data obtained from the study Results: In all the 50 specimens, marginal mandibular nerve emerged from the cervicofacial ramus of facial nerve. 26% specimens showed single branch of the nerve, in 56% specimens, two branches were observed, and in 18% specimens, three branches of marginal mandibular nerve were observed. 76% the nerve coursed inferior to mandible. The average distance of the nerve from the inferior margin of the mandible was 1.4 cm. In 96% of the specimens, the nerve coursed lateral to the facial vessels. In 4% of the specimen, the branches of the nerve were found both lateral and medial to the facial artery. Communication of the nerve with buccal branch was observed in 16% of specimens. Conclusion: As the marginal mandibular nerve shows lot of variations, a proper anatomical knowledge on the same helps the patients to have a good treatment preventing any iatrogenic complications. KEY WORDS: Marginal mandibular nerve, Facial artery, inferior margin of the mandible, Facial nerve.

Abstract The use of wireless charging technology for Electric Vehicles (EVs) is gaining increasing significance due to its ability to charge batteries safely and conveniently without the need for physical connectors. This paper presents the design and implementation of the transmitter-side power conversion system for a wireless EV charging station. The proposed system architecture integrates a front-end Power Factor Correction (PFC) rectifier, an Interleaved Resonant DC-DC converter, and a three-level Neutral Point Clamped (NPC) inverter, providing a highly efficient and stable power transmission path for battery charging. The Interleaved Resonant DC-DC converter, designed with a Zero Voltage Switching (ZVS) mechanism, minimizes switching losses and enhances overall efficiency. Its operation under Constant Current (CC) and Constant Voltage (CV) control modes ensures smooth and reliable mode transition through an auxiliary controller incorporated alongside a conventional PI controller. The inverter stage adopts a Modified Space Vector Pulse Width Modulation (MSVPWM) strategy that significantly reduces Total Harmonic Distortion (THD) in both voltage and current waveforms, thereby maintaining compliance with power quality standards. The complete system's performance has been evaluated through both simulation and experimental validation. MATLAB/Simulink-based analysis demonstrates stable converter dynamics with a regulated output voltage of 325 V and negligible transient disturbances during mode transitions. A 0.2 kW laboratory prototype was developed to confirm the simulation results using PIC24F16KA102 and FPGA-SPARTAN-7 controllers for power and switching signal generation, respectively. Experimental measurements indicate that the proposed Interleaved Resonant DC-DC converter achieved an efficiency of approximately 95.35% at rated load, which aligns closely with theoretical predictions. The three-level NPC inverter produced a 320 V output with voltage and current THD levels of 4.8% and 5.6%, respectively. A 2:1 air-core transformer designed for high-frequency operation (100-200 kHz) effectively transfers power to the EV receiver side. The influence of coupling coefficient and air-gap variation on transfer efficiency was systematically investigated, revealing an optimal separation distance of 10-20 mm. The overall results confirm the efficacy of the proposed design for high-efficiency wireless EV charging. Future work will concentrate on optimizing the receiver-side converters to further enhance system efficiency and dynamic performance.