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Respiratory Motion Prediction of Lung Tumor Using Artificial Intelligence
Managing respiratory motion in radiotherapy for lung cancer presents a formidable and newlinepersistent challenge. The inherent dynamic movement triggered by respiration introduces a notable degree of uncertainty in target delineation, impacting the precision of image-guided radiotherapy. Overlooking the impact of respiratory motion can lead to the emergence of artifacts in images during image acquisition, resulting in inaccuracies in tissue delineation. Moreover, the motion between treatment fractions can induce blurriness in the dose distribution within the treatment process, thereby introducing geometric and dosimetric uncertainties. Additionally, inter-fraction motion can result in the displacement of the distribution of administered doses. Given these complexities, the precise prediction of tumor motion holds the utmost importance in newlineelevating the quality of treatment administration and minimizing radiation exposure to healthy tissues neighboring the pertinent organ during radiotherapy. Nonetheless, achieving the desired level of precision in dose administration remains a formidable task due to the inherent variations in internal patient anatomy across varying time scales and magnitudes. While notable advancements have been witnessed in radiotherapy, attributed to innovations like image guidance tools, which have streamlined treatments, the challenge of accommodating lung tumor motion remains critical, particularly in cases related to newlineradiotherapeutic intervention. Substantial limitations endure despite integrating respiratory-gated techniques in radiation oncology to manage lung tumor motion. Moreover, lung cancer prognosis remains low, irrespective of the recent advancements in radiotherapy. The practice of expanding newlinetreatment margins from the Clinical Treatment Volume (CTV) to encompass the Planning newlineTreatment Volume (PTV) has been adopted as a strategy to amplify treatment outcomes. newlineHowever, this strategy necessitates a trade-off, as it inevitably exposes larger volumes of healthy tissues to radiation. -
Clonning and Characterization of An Exported Protein Present in the RD7 Region of Clinical Isolates of Mycobacterium Tuberculosis
The bacterium Mycobacterium tuberculosis is responsible for causing the disease newlinetuberculosis in mammals, which is regarded as one of the oldest diseases haunting the human race. The only available tuberculosis vaccine Bacillus Calmette-Guerine (BCG), is effective against childhood tuberculosis but is regarded as having low efficacy in conferring protection in the case of tuberculosis in adults. A comparison of the M. tuberculosis H37Rv strain and clinical isolates from Kerala had earlier revealed that the clinical strains have a distinctive 4.5 kb genomic sequence that is lacking from the H37Rv strain in the RD7 region. The RD7 is a distinctive genomic region that is absent in M. tuberculosis H37Rv and Mycobacterium bovis BCG strain. The 4.5 kb genomic sequence is projected to include 6 potential ORFs by newlineNCBI ORF prediction tool, one of which Novel Hypothetical Protein (NHP2) is anticipated to encode an exported protein with a length of 268 amino acids. Studies demonstrate that Mycobacterium tuberculosis secretory proteins such as the Ag85 complex, the ESAT-6 family protein, and the PE-PPE family proteins were newlineeffective vaccine candidates because they trigger T cells. Here, we present an indepth analysis of the exported protein, which is 268 amino acids long. The putative exported protein with a gene 807 bp long was PCR amplified and cloned in the expression vector pET-32a for expression. The protein was over expressed using Isopropyl D-1-thiogalactopyranoside (IPTG) and was isolated and purified using column chromatography. Bioinformatics studies were conducted to study the characteristics of the expressed protein. A novel putative mycobacterial protein discovered by subtractive hybridization was studied for its potential as a vaccine candidate using cutting-edge computer technologies. -
Forcing Parameters and Propagation Time of Certain Graph Classes
A branch of mathematics that treats vertices and edges of a graph is called graph theory. This theory is used to replicate many real-life situations and physical problems. Graph coloring problem is one of the prominent studies in extremal graph theory. Suppose information has to be communicated in a network or some product has to be marketed to all the people in a cluster then there are two types of cost that needs to be encountered, one the cost of selecting the initial set of vertices in a network and the second is, time it takes to propagate the information through the entire network. The sum of these two parameters is known as the total cost. Optimizing the total cost, which is the sum of vertices and the time it takes to propagate information through the entire network, is a challenging problem for any newlinegraph. Such an interesting and well-studied problem is called the dynamic coloring newlineproblem. The forcing problem also known as infecting or spreading problem is one newlinesuch dynamic coloring problem where two colors- white and black are used. Assume that a fxed set of vertices in a graph G are initially black and that the remaining vertices are considered white vertices. The aim of the forcing process is to obtain, fully black-colored vertices of the graph G by progressively applying the color change law, making sure that at least one white vertex is forced black in every discrete time interval. The forcing index is the minimum cardinality of the forcing sets. Diand#64256;erent types of forcing, such as one forcing, connected one forcing, k-forcing connected k-forcing etc., are defned based on the color change law. The one forcing is the basic form of forcing. A generalised form of one forcing is known as k-forcing where k lt V (G). The time taken by a forcing set to force the entire vertices of the graph G black is the propagation time or iteration index. The subject of study aims to fnd the one forcing number and k-forcing number of diand#64256;erent types of graph classes and derived graph classes. -
Design, Training, and Implementation of A New Individualized Education Plan (IEP) Format For Special Educators And Students With Intellectual Disabilities At Selected Special Schools
An individualized Education Plan (IEP) is a multidisciplinary, teamdeveloped plan required for every child receiving special education services. The researcher delved into concerns surrounding Individualized newlineEducation Programs (IEPs) for students with intellectual disabilities. Two significant hurdles were discovered: existing IEPs lacked essential intervention areas, and special education teachers felt inadequately newlineequipped to construct effective plans. newlineThe study tackled these concerns head-on through a multi-pronged approach. Firstly, a meticulous analysis of existing IEPs revealed crucial sections missing from intervention plans, hindering their effectiveness. newlineThis analysis served as the blueprint for crafting a more comprehensive IEP format that addressed the identified gaps and provided a robust framework for intervention. Next, the study focused on empowering special education teachers. Sixty special education teachers certified by the Rehabilitation Council of newlineIndia, participated in training sessions on the new format, undergoing a vital skills and knowledge upgrade in IEP development. This equipped them with the tools and understanding necessary to create more effective plans tailored to individual student needs. The theory then transitioned to practice. Students with intellectual newlinedisabilities were included in interventions based on the improved IEPs, with their progress closely tracked and evaluated. The results were highly promising. Teachers demonstrated a tangible improvement in knowledge, translating into their ability to create more effective IEPs. More importantly, students thrived with the enhanced format. Those involved in interventions using the improved IEPs exhibited significant progress in various domains, highlighting the positive impact of the new approach. The study culminated in key recommendations for further newlineimprovement. Ongoing teacher training sessions were suggested to ensure teachers remain updated on best practices and evolving methodologies. -
Comparative Study of Product Liability and Data Confidentiality in Case of Intermediaries with Special Reference to India and The European Union
Technology has played a major role in human development. The advent and invention of wheel and fire changed the coverage of human society. On a similar note in 90 s a technology called internet was developed and it changed all rules of the game. This technology removed all hindrances of place and time. It created faceless market place wherein; consumer not only have huge choices and varieties but also, they can create goods and services on their own. This was the origin of Electronic Business and it gave birth to new breed of middleman / intermediaries to facilitate it. These intermediaries are application provider, ISP, network service provider etc. The mantras of success were wide choices and data. But this mantra created a new legal challenge of data handling and liability for defects in goods and services. Researcher has studied and analysed all dimensions of intermediaries newlineand how they handled the two new legal challenge of data confidentiality and newlineproduct liability. In addition, researcher has examined the legal framework of India and compared it with legal framework of European Union and finally concluded on the coverage and effectiveness of Indian legal structure and what India learn and implement from European Union. This thesis mainly focusing on generic business model used by intermediaries. Issues like IPR, industry specific domain like financial systems and medical domain are excluded. Researcher followed the doctrinal research methodology to understand the evolution of intermediaries, product liability, data confidentiality in India by various primary resources like the Indian Laws i.e., Consumer newlineProtection Act, 2019, Indian Contract Act, 1872, Information Technology Act, 2000 and other various statutes. This thesis compares Indian legal framework with European Union and test the hypothesis of coverage and effectiveness of Indian legal structure with European Union. -
Development of Privacy Preserving Machine Learning Techniques Using Secure Multi-Party Computation
Machine learning (ML) has brought about a paradigm shift in insight generation across various domains, including healthcare, finance, and pharma, by leveraging historical data. However, the effectiveness of ML solutions hinges on the seamless collaboration between data owners, model owners, and ML clients while ensuring that privacy concerns are meticulously addressed. Unfortunately, existing privacy-preserving solutions have not been able to offer efficient and confidential ML training and inference. This has led to an increased focus on Privacy-Preserving Machine Learning (PPML), which has become a flourishing area of research aimed at safeguarding the privacy of machine learning stakeholders. In this regard, the present research introduces novel techniques for private ML inference and training of models using Secure Multi-Party Computation (SMPC) and Differential Privacy (DP) methods on horizontally and vertically partitioned datasets. The proposed techniques are implemented using Python with open-source libraries such as SyMPC and PyDP to ensure confidential inference and model protection. The findings across various parameters illustrate the effectiveness of the suggested techniques in addressing the privacy concerns of model owners and inference clients, with no significant impact on accuracy and a linear influence on performance as the privacy parameters, such as secure nodes count within the SMPC cluster. are increased. Furthermore, the privacy gain is substantiated by information privacy measures such as Mutual Information and KL-Divergence across different privacy budgets, which demonstrate empirically that privacy can be preserved with high ML accuracy and minimal performance cost. -
Volatility Spillover Effects in Cryptocurrencies
Cryptocurrencies' growing use has increased investors and decision- makers interest. Cryptocurrencies' volatility and how it impacts others is most intriguing. Arguments include speculative pressures, valuation uncertainty, and lack of regulation. These traits cannot fully explain cryptocurrency volatility and volatility spillovers, suggesting other relevant factors. In this study, currency volatility and spillovers, as well as their relationship with the sentiment of global investors, were investigated. The study analysed 22 cryptocurrencies from 01/01/2018 to 31/12/2022. The study used FIGARCH and FIEGARCH, a GARCH family model to analyse the long-memory and leverage effects on cryptocurrency volatility, the ADCC-GARCH framework, and the Diebold-Yilmaz spillover index to analyse cryptocurrency volatility spillovers. The long-memory and leverage impacts on bitcoin volatility were analysed using the FIGARCH and FIEGARCH models from the GARCH family. Both the Chow-test and the Pai-Berron Test found structural breaks in the cryptocurrencies. Cryptocurrencies such as Adacordono, Aertinity, ARK, BAT, BCH, BNT, BTC, Dogecoin, Ethereum, Funtoken, ICON, KMD, KNC, NEO, PIVX, QTUM, SNT, TRX, ZCASH, have positive (difference) FIGARCH coefficient values. It indicates a long memory in currencies, and volatility shocks affect future volatility. On the other hand, the FIGARCH coefficient of BTG cryptocurrency (difference) is negative (-0.035), which suggests that the individual has a short memory. In this scenario, the effects of volatility shocks are only temporary. When extreme volatility is promptly followed by low volatility or vice versa, this indicates anti- persistence. The study also found that both positive and negative news has a significant impact on the volatility of specific cryptocurrencies such as BCH (0.015), BNT (0.0016), BTG (0.01972), DOGE (0.2296), EOS (0.0112), KNC (0.0366), PIVX (0.0021), TRX (0.0013), Adacordono (- 0.027), Aertinity (-0.0393), ARK (-0.0377), BAT (-0.028058), and BTC (-0.0665). Ethereum has the largest spillover (4.09), followed by QTUM (4.06), EOS (4.05), Adacordono (4.05), and Dogecoin (2.4). All cryptocurrencies show fundamental instabilities (P-values less than 0.05). Hence the alternative hypothesis is accepted, and the null hypothesis is rejected. The hill estimator tail index value is ? > 0, fat tail or heavy tail; high chance of catastrophic event which is observed in all the 22 cryptocurrencies. Both investors and speculators can use sentiment analysis to forecast market volatility and generate gains. Policymakers can also utilize this information to establish laws that reduce market volatility. As a result, the study contributes to the ongoing discussion on the factors that cause bitcoin's volatility.3 -
Relationship Between Industry-Associated Value Premium and Firm Risk Charaterstics on Stock Returns : Evidence From Indian Stock Market
The body of academic literature consistently debates that firms with low PB (price to book) outperform firms with high PB characteristics. This study examines whether the academic literature-promised value premium has any industry association in the Indian equity market and tests the existence of other anomalies: size, investment, profitability, and R&D, in explaining the cross-sectional variability of stock returns. The study considers all BSE-listed firms actively trading between 1999-2021, using time-series, multivariate, and cross-sectional models on each industry-level portfolio. Results indicated that a significant value premium exists in 18 out of 21 industry groups. Both industry and firm-level value premiums are identified; however, the firm-level premium seems more prominent. The value premium is most substantial in small-cap value stocks of value-and-growth-oriented industries, large-cap value stocks of value-oriented industry groups, then small-cap growth stocks of value-and growth-oriented industries and large-cap growth stocks of value- and growth-oriented industries. Interestingly, the sub-period analysis revealed variation in the value premium, indicating that the industry-associated value premium has been relatively low in the current decade. It is due to decreasing tendencies in industry returns and increasing PB in industries. The study explores R&D premium and compares existing factor premiums. Results showed that India's annualized average R&D premium is significantly higher than the current value, profitability, size, and investment premiums, particularly for highly R&D intensive firms. To check the robustness of the findings, the study used the multivariate GRS (Gibbons Ross Shanken) test and the regression models. It confirmed that size and value premiums are the most prominent determinants of industry-level equity returns. The profitability and investment premiums also influence industries' returns. Investors who seek to allocate assets within and across industries are likely to have predictable and stable returns. -
Production Of Boeravinone B And Related Bioactive Molecules From Cell Cultures Of Punarnava, Boerhavia Diffusa Linn.
Boerhavia diffusa L., commonly referred to as punarnava, belongs to the Nyctaginaceae family. It contains a variety of phytochemicals that contribute to the plant's pharmacological activities. Among these compounds, Boeravinone-B, a significant secondary metabolite synthesized within the plant, has been reported to possess various pharmacological properties, including antioxidant, anti-inflammatory, cardio-protective, antimicrobial, and anti-cancer activities. Given its potential, there is a growing need to produce Boeravinone-B through biotechnological approaches such as plant tissue cultures. However, limited studies have been conducted on its production via tissue culture. Therefore, our objective was to produce Boeravinone-B using callus and cell suspension cultures. To induce callus, different auxins (2,4-D, NAA, IAA, IBA, and picloram) and cytokinins (kinetin, BAP, TDZ, and 2-iP) alone and in combination to maximize biomass and Boeravinone-B production was employed. Results showed that semi-solid medium supplemented with 5.0 mg/L 2,4-D produced the highest biomass and Boeravinone-B production from leaf explants. Subsequently, we established cell suspension cultures and observed that a combination of 2.0 mg/L picloram and 5.0 mg/L NAA yielded the highest production of Boeravinone-B. We further optimized cultural conditions such as inoculum density, carbon sources, sucrose concentration, MS medium strength, pH, ammonium and nitrate ratio, and various concentrations of macronutrients to enhance Boeravinone-B production. Additionally, we explored elicitation strategies using both biotic and abiotic components to determine their effects on Boeravinone-B production. Elicitation involved the use of polysaccharides (chitosan), fungi (yeast extract, Aspergillus niger and Cordyceps militaris) bacteria (Escherichia coli and Bacillus subtilis), and algal members (Valonia utricularis and Spirulina platensis). Likewise, signalling molecules (salicylic acid, sodium nitroprusside, and ethephon), polyamines (putrescine, spermine, and spermidine), and heavy metal salts (lead acetate, cadmium chloride, and lanthanum chloride) to stimulate Boeravinone-B production. Significant variations were observed among the elicitors in their ability to promote Boeravinone-B production, with the order of effectiveness being spermidine > Spirulina platensis > salicylic acid > spermine > sodium nitroprusside > Aspergillus niger > Valonia utricularis > Cordyceps militaris > yeast extract > putrescine. By employing these elicitation strategies alongside advancements in molecular aspects and large-scale production in bioreactors, we can ensure a sustainable supply of Boeravinone-B and its associated metabolites. -
Experience of Resilience in Women with Breast Cancer : Implication for Resilience-Based Intervention
Breast cancer is prevalent among Indian women and affects their physical, emotional, and social well-being. Resilience in breast cancer refers to the ability to maintain newlinepositivity and adapt to challenges. However, evidence-based studies and theoretical newlineframework interventions on resilience in the Indian context are lacking. The current newlinestudy aims to explore the subjective experience of resilience and intend to provide resilience-based intervention in Indian women with breast cancer. The study also explores sociodemographic, clinical outcomes, relation with resilience, quality of life and posttraumatic growth in the Indian context. The study uses a qualitative approach with phenomenological paradigm to understand the patterns, processes and outcomes in exploring the concept of resilience. Purposive sample of 33 participants from two hospitals in Bengaluru, India were recruited. The participants consisted of 21 breast cancer survivors on follow-up, four on anti-cancer therapy and eight family members of breast cancer survivors for triangulation. Along with sociodemographic, clinical details, and the Connor-Davidson Resilience Scale (2003) to screen for categorising the resilience levels was collected. The in-depth interview guide was validated with experts to collect data. The interviews were tape-recorded, transcribed, and subjected to member checks, triangulation, intercoder reliability, and thick description to ensure the validity of the findings. The data was analysed using reflective thematic analysis by Braun and Clarke (2019). The finding describes four themes of experience of resilience in women with breast cancer. (1) Cancer diagnosis is a life-changing experience. Breast cancer diagnosis and therapy causes existential crisis, psychological distress, and social stigma. (2) Restoring healthy perception in an adverse event. Navigating challenges and achieving a balance between internal and newlineexternal factors. (3) Types of support-the pathway to resilience. -
A Study on Some Eccentricity Related Problems in Graphs
The concepts related to eccentricity in graphs are explored in this research work. newlineThe eccentric graph Ge of a graph G has the same vertex set as that of G and two newlinevertices in Ge are adjacent if one is the eccentric vertex of the other. The eccentric newlinegraphs of some graph operations are explored, and the iterated eccentric graphs Gek newlineare introduced. The process of inding eccentric graphs, known as eccentrication, is newlinestudied in detail. Graphs that result in a complete graph Kn upon iterative eccentrication are characterized, and the cyclic property of eccentrication is established for various cycle-related graphs. The eccentrication of tree graphs is studied in detail, and a general result on the cyclic property of trees is obtained. A conjecture on the cyclic property of eccentrication for any graph G is made. The ei-signed graph of a graph G, where the edge between vertices u and v receives a sign and#963; = (and#8722;1)|ecc(u)and#8722;ecc(v)|, where ecc(u) is the eccentricity of vertex u, is investigated. General properties of ei-signed graphs, such as homogeneity, consistency, switching, and sign compatibility, are discussed. Properties that behave diferently across various classes of graphs are explored. Finally, the scope of this study is presented, and some open problems in the area are provided. -
Role of Humanoid Robots in Enhancing Communication and Social Skills among Students with Mild Autism
Introduction Children with Autism Spectrum Disorder (ASD) face challenges in social newlineinteraction. This is a growing concern and needs a due redressal for their wellbeing. Failing to address these challenges can cause further isolation resulting in displaying antisocial behaviours. Children with Autism require the intervention of technology. Over the years, special schools have been using newlineAssistive Technologies (AT) that bridge the gap in learning for students with newlinedisabilities in general and Autism in particular. As a result of this initiation newlineearlier studies have deciphered that the end result of drawing AT into teaching and learning have been promising and optimistic. Available literature has shed light on the positive impact of emerging and assistive technologies on the learning of students with disabilities. However, the use of emerging newlinetechnologies by special tutors to build vital skills amongst children with autism has not been sufficiently explored. The lack of adequate exploration in the aforementioned domain paves the way for this research in particular. Objectives This study aims to explore the benefits of using humanoid robots which is an emerging technology in recent years with specific reference to inclusive newlineclassroom setup. Inclusive classrooms use humanoid robots to develop social and- communication skills amongst students with mild autism. This study sheds light by using both qualitative and quantitative methods and identify whether robots can effectively address children s social and communication skills which contributes to children s speech and behavioural development. Methods As mentioned above this research has been undertaken with a qualitative research design a combination of tools to explore how humanoid robots enable in the development of social and- communication skills amongst students with mild autism. The researcher has conducted semi-structured interviews newlinewith special tutors and counsellors to gain insights into the positive benefits of newlinechild - robot interaction. -
Effectiveness of the Services Delivered by Special Schools for Children with Intellectual Disability
Special schools are the most widespread in the country among the various models for the education of children with intellectual disabilities. In India, there are large number of special schools for children with intellectual disabilities, implementing special education programme using various methods and materials. The present research attempts to determine the effectiveness of special schools rendering services for children with intellectual disability. A comprehensive understanding of the practices followed by different special schools would provide more insight into the functioning of special schools that serve children with intellectual disability. This study explores the various practices in special schools and the progress of children in self-care, behaviour and communication after receiving special education. The study also focused on understanding the progress of children with mild, moderate, and severe intellectual disability. The study used mixed research method. A causal design was used to assess special schools' effectiveness with a focus on self-care, behaviour, and communication of children. Both quantitative and qualitative method of data collection and interpretation were done to conclude the study. The self-structured interview schedule was used for qualitative research and collected information from 12 special schools. Cases were developed based on the qualitative data. Within-case and cross-case analysis with thematic analysis were used for analyzing the data. Quantitative data was collected from caretakers of 98 children, using a standardized tool Behavioural Assessment scale for Indian Children with Mental Retardation (BASIC- MR). The impact of special education on the self-care, communication and behaviour of Children with Intellectual Disabilities were analyzed with Wilcoxon Signed Rank test using the baseline data and their progress of the children after five years in special school. The result shows that there are changes in behaviour, self-care and communication of children with ID after they joined special school. The results also highlighted that there is a difference in children's progress based on the level of intellectual disability (mild, moderate and severe). The qualitative analysis explained the best practices exhibited by special schools for children with ID. -
Study of Classical Be Stars in Open Clusters in the Galaxy
Classical Be stars (CBe) in open clusters older than 100 Myr are identifed. The objective is to study their characteristics relating to age, spectral type and evolutionary state. This study compliments with that of Mathew et al. (2008), where they identifed and characterized emission-line stars in open clusters younger than 100 Myr. For this research, we surveyed a sample of newline71 open clusters older than 100 Myr using the slitless spectroscopy technique, with the Himalayan Chandra Telescope (HCT). From the survey we identifed 15 CBe stars from the 11 open clusters older than 100 Myr. Out of 15 CBe stars, 13 CBe stars show Hand#945; in emission. Among these CBe stars, TYC 2679-432-1 is a new detection, belonging to Berkeley 50 open newlinecluster. Two more CBe stars, out of 15 CBe stars, are found to exhibit Hand#945; in absorption for the frst time. This suggests that they might be passing through a disc-loss episode (or transient phase). Apart from our survey of 71 old open clusters, we found additional 16 Be stars from 6 open clusters older than 100 Myr in the literature (which was not observed in the slitless survey due to observation limitations). In addition to HFOSC instrument mounted on HCT, we used Opto Mechanics Research (OMR) spectrograph newlinemounted on 2.3-m Vainu Bappu Telescope (VBT) for taking the slit spectra of CBe stars. We performed the optical spectroscopy of 16 classical Be stars in 11 open clusters older than 100 Myr. Among these 16 stars, 15 newlinewere identifed from our previous slitless spectroscopic study. The remaining one, LS III +47 37b is a new detection, which is confrmed through the present study. Our analysis also suggests that one out of these 16 stars, [KW97] 35-12 might be a weak Hand#945; emitter in nature showing Hand#945; EW of -0.5 Moreover, it is found that the Hand#945; EW for 15 stars is lt -40 in agreement with previous works. Interestingly, we did not observe any FeII emission line or even the OI 8446 emission feature in any of our sample stars. -
Optical Spectroscopy of Classical Be Stars in The Galaxy
A classical Be (Be hereafter) star is a special type of massive B-type main newlinesequence star surrounded by a geometrically thin, equatorial, gaseous, decretion disc orbiting the central star. Spectra of Be stars show emission lines of different elements. Studying these lines provide an excellent opportunity to understand the geometry and kinematics of the circumstellar newlinedisc and properties of the central star itself. Be stars, thus provide excellent opportunities to study circumstellar discs. However, the disc formation mechanism in Be stars the Be phenomenon is still poorly understood. The present study focuses on studying a large sample of Be stars through newlineoptical spectroscopy and using two national optical telescope facilities. We performed the spectroscopic study of all major emission lines for a sample of 115 feld Be stars in the wavelength range of 3800 - 9000 using the 2.1-m HCT facility at Ladakh. To our knowledge, this is the frst study where near simultaneous spectra covering the whole spectral range of 3800 - 9000 has been studied for over 100 feld Be stars. We, therefore, produce an atlas of emission lines for Be stars which will be a valuable resource for researchers involved in Be star research. We made use of the unprecedented capability of the Gaia mission to re-estimate the extinction parameter (AV ) for these stars. The estimated AV values are used for extinction correction in the analysis of Balmer decrement (D34 and D54) for our program stars. D34 in our sample ranges between 0.1 and 9.0, whereas the corresponding D54 value mostly (and#8776; 70%) ranges between 0.2 and 1.5, clustering somewhere near 0.8 and#8722; 1.0. Our study indicates that Be star discs are generally optically thick in nature in majority of the cases. Through comparative study with the literature, we also noticed that the Hand#945; EW values in Be stars are usually lower than -40 Further from our analysis, it appears that the emission strength of Hand#945;, P14, FeII 5169 and OI 8446 is more in early B-type stars. -
Study of Early-Type Emission -Line Stars in the Galaxy Using Lamost and GAIA
The study of massive emission-line stars (ELS), particularly those classifed as O, B, and A spectral types, is crucial in advancing our understanding of various fundamental aspects of astrophysics. They provide valuable insights into the accretion processes, the physical conditions of material around the star, and the stellar evolution. The frst theme of thesis focuses on identifying and characterising hot ELS newlinefrom large spectroscopic surveys such as LAMOST and Gaia DR3. Utilising the low-resolution spectroscopic database provided by LAMOST DR5, we employed an automated Python routine and identifed 3339 unique sources encompassing 4138 spectra that exhibited Hand#945; in emission. Since both HAeBe stars and Classical Ae/Be stars show Hand#945; emission, we differentiated them in terms of IR excess, from the analysis of 2MASS and WISE photometry. This analysis led to the identifcation of 1089 Classical Be stars, 233 Classical Ae stars, and 56 Herbig Ae/Be (HAeBe) stars. This homogeneous emission-line spectra will facilitate detailed investigations of the emission phenomenon, removing concerns related to data compilation newlinebiases from diverse sources. We also compared the astrophysical parameters obtained from Gaia DR3 with those derived from LAMOST spectra. The emission-line source classifcations in Gaia DR3 were reasonably consistent with those in the LAMOST OBA emission catalogue. Additionally, newlinewe used a larger dataset of ELS to update the empirical relation for converting pseudo-equivalent width to observed equivalent width in Gaia DR3, employing a second-degree polynomial relation and piece-wise linear ft newlineparameters. As the second theme of the thesis, we examined the X-Shooter spectral newlinedatabase to study the circumstellar medium of HAeBe stars through various spectral features and near-infrared excess. We observed that the ma-jority of massive and young stars exhibited emission in all higher-order HI newlinelines, while stars displaying only lower-order lines had effective temperatures below 12000 K and ages ranging from 5 to 10 Myr. -
Design, Synthesis, and Applications of Carbon Dots with Controlled Physicochemical Properties
Modification of carbon dots (CDs) is essential to enhance their photophysical newlineproperties and applicability. Physical (e.g., composite material blending, coreshell architecture) and chemical (e.g., doping, surface passivation) methods exist to modify CDs. Different precursors can impart varied functionalities and heteroatomic dopants on CDs. Despite several modification strategies, the reproducibility and scalability of CDs still need to be improved. Newer approaches for modifying CDs are thus essential to ensure lab-to-lab and batchto-batch consistency. Our study focused on developing novel strategies for the physicochemical modifications of CDs. The theoretical simulation we performed for surface-functionalised CDs with the aid of density functional theory and time-dependent density functional theory helped to predict the mechanism of photoluminescence (PL) and to analyse the effect of hydrogen bonding on the newlineproperties of CDs (Chapter 3). We have developed a novel and general method for preparing amine functionalized CDs from modified paper precursors (Chapter 4). This strategy allows us to prepare CDs with customized functionalities, alleviating the post-synthesis modification. A novel ionimprinting strategy involving CDs synthesised from modified paper precursors newlinewas also developed through our research (Chapter 5). In another work, we utilized silk fibers as a matrix for immobilising CDs (Chapter 6). CDs prepared from mulberry leaves were fed to silkworms to produce CD-embedded silk fibres, which could be used to detect dopamine. In addition, we prepared CDs newlinefrom an unreported natural source (frankincense), which were used to detect lead ions (Chapter 7). We demonstrated the heavy metal sensing application of these newlineCDs in combination with a UV-light LED chip and a smartphone, which is relevant in resource-limited areas. The research results presented in the thesis are expected to inspire further investigations and applications related to CDs. -
Synthesis, Adsorptive Properties and Applications of Modified Aluminum Oxyhydroxide-PVA Films
Over the past few years, there has been an increasing interest in polymer films and newlinemetal-incorporated polymer films because of their distinctive characteristics and newlinepotential applications. The effectiveness of alumina or modified alumina polymer films newlineas adsorbents or catalysts is greatly influenced by their surface properties, texture, chemical composition, and thermal stability. This thesis describes the synthesis of aluminum oxyhydroxide - polyvinyl alcohol composite films by sol-gel method. The synthesized films were modified by incorporating transition metals and cross-linking agents depending on the desired application as a catalyst or adsorbent. The synthesized films were characterized using different techniques, like powder X-ray diffraction studies (pXRD), Fourier transform infrared spectra (FTIR), Raman spectra, BrunauerEmmett-Teller surface area (BET), Barrett-Joyner-Halenda (BJH) isotherm, atomic newlineforce microscopy, optical profilometry, thermogravimetric analysis, Scanning electron newlinemicroscopy (S.E.M), and X-ray photoelectron spectroscopy (XPS) to determine the newlinestructural and textural properties. The films were deployed as adsorbents for the removal of heavy metals and dyes from water as well as catalysts for industrially important organic transformations. The results of the characterization studies were used to correlate the surface characteristics and adsorptive capacities of the fabricated films. The films were found to have tuneable surface properties and enhanced adsorptive newlinebehaviour, which could be modified as per the application. Transition metalincorporated films exhibited remarkable adsorption properties for the elimination of heavy metals and organic dyes from aqueous solution. The adsorption reaction kinetics newlinewere investigated to ascertain the rate and mechanism of the reaction to improve the newlineefficiency, economic efficiency and environmental sustainability of the reaction. -
Fabrication of Molecularly Imprinted Electrochemical Sensors for Food Additives
Molecularly imprinted polymers (MIPs) have emerged as a promising technique for the newlinepreparation of synthetic polymers with specific binding sites for target molecules. These polymers have found applications in various fields, including sensing, where they serve as a recognition element for the detection and quantification of analytes in chemical and biological environments. In recent years, MIPs have been utilized as sensing materials for biomolecules, food additives, pesticides, metal ions, and other target species. This work presents the development of MIP-based electrochemical sensors for the selective and rapid detection of food additives, namely tartrazine, 4-hexylresorcinol, butylated hydroxy anisole, and brilliant blue FCF. Conducting polymers, metal nanoparticles and 2D material-based electrode modifications have been employed in newlinethe preparation of MIPs for electrochemical sensing applications. Investigations reveal newlinea significant enhancement in the electrochemical oxidation/reduction current of the analytes upon the surface modifications applied to the Carbon Fibre Paper (CFP) substrate. The surface morphology of the modified electrodes was characterized using techniques such as Field Emission Scanning Electron Microscopy (FESEM), Electron Diffraction X-ray (EDX), X-Ray Photoelectron Spectroscopy (XPS), Optical newlineProfilometry, and Fourier Transform Infrared Spectroscopy (FTIR). Nyquist plots newlinedemonstrated the lowest charge transfer resistance at the finally modified working newlineelectrodes compared to other control electrodes. Optimization of experimental newlineconditions, including pH effects, investigation of reaction mechanisms through scan rate variations, determination of the number of cycles required for film newlineelectrodeposition to achieve maximum current response, and determination of the potential window, was carried out using cyclic voltammetry (CV). The quantification newlineof analytes was performed using Differential Pulse Voltammetry (DPV). -
Modified Carbon-Based Composites and Their Electrochemical Studies
Energy storage has emerged as the world's most important issue, attracting the focus of researchers and commercial developers due to the economy's rapid growth and the rise in the usage of portable electronics and electronic vehicles. These devices make it possible to efficiently capture and store the excess energy produced during times of high generation, so that it can be used when there is little or no generation. Devices for storing renewable energy contribute to grid stability and lessen the reliance on fossil fuel-based power plants. Moreover, they contribute to the decarbonization of the energy industry, mitigating climate change, and promoting a sustainable future. This thesis explores the potential of modified carbon-based composites as advanced materials for energy storage applications particularly supercapacitors and solar thermal fuels. The research focuses on the careful design and synthesis of ternary composites, incorporating carbonaceous materials such as carbon nanotubes, graphene oxide, and graphitic carbon nitrides, metal sulphides, nitrogen rich moieties, and conductive additives like polyaniline and polypyrrole. A wide variety of methodologies were used to describe the structural and morphological characteristics of the composite materials. Thermogravimetric analysis, Fourier transform infrared spectroscopy, X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, and other techniques were used. These methods gave important information about the composite materials' chemical structure, type of bonding and arrangements, surface morphology, and thermal stability. Electrochemical techniques, such as cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy, have been extensively employed to investigate the performance and behaviour of supercapacitor electrodes and devices. The results demonstrate significant improvements in electrochemical performance, including enhanced specific capacitance, excellent cycling stability, and remarkable rate capability. These findings indicate that the modified carbon-based ternary composites hold promise for high-performance energy storage devices. Ultimately, this research contributes to the development of next-generation energy storage technologies, offering more efficient and sustainable solutions for storing energy.