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Identifying the population of T-Tauri stars in Taurus: UVoptical synergy
With the third data release of the Gaia mission, Gaia DR3 with its precise photometry and astrometry, it is now possible to study the behavior of stars at a scale never seen before. In this paper, we developed new criteria to identify T-Tauri stars (TTS) candidates using UV and optical color-magnitude diagrams (CMDs) by combining the GALEX and Gaia surveys. We found 19 TTS candidates and five of them are newly identified TTS in the Taurus molecular cloud (TMC), not cataloged before as TMC members. For some of the TTS candidates, we also obtained optical spectra from several Indian telescopes. We also present the analysis of distance and proper motion of young stars in the Taurus using data from Gaia DR3. We found that the stars in Taurus show a bimodal distribution with distance, having peaks at 130.17-1.241.31 pc and 156.25-5.001.86 pc. The reason for this bimodality, we think, is due to the fact that different clouds in the TMC region are at different distances. We further showed that the two populations have similar ages and proper motion distribution. Using the Gaia DR3 CMD, we showed that the age of Taurus is consistent with 1Myr. 2023, Indian Academy of Sciences. -
Topic Modelling of ongoing conflict between Russia and Ukraine
Online news sites provide hotspots to extract popular ratings and opinions on a wide range of topics. Realizing what individuals are referring to and understanding their concerns and suppositions is exceptionally significant to organizations and political missions. Furthermore, it is incredibly difficult to physically peruse such enormous volumes of data and gather the themes. Keeping in mind the prevailing plight of war-Torn nations such as the recent conflict between Russia and Ukraine. This study performs aims to perform topic modelling using LDA (Latent Dirichlet Allocation) and text analysis on datasets collected from various online news websites. To increase the accuracy and efficacy of the topic modelling, a comparative analysis is proposed that elevates the performance of machine learning models. This study also develops an algorithm where the entire process can be automated from the point of data collection to finding optimum array of topics in the given dataset. Searching for insights from the collected information can therefore become very tedious and time-consuming. Topic modelling was designed as a tool to organize, search, and understand vast quantities of textual information. The topic model using LDA was utilized to do a text analysis for this research. In the beginning, researchers have scraped a total of 1178 articles that covered the war conflict between Russia and Ukraine from December 1, 2021, to May 16, 2022. After that, researcher built the LDA model and modified hyper parameters based on the coherence score Cv that was used for the model evaluation technique. When using the most effective model, prominent topics, and representative documents pertaining to each topic, topic allocation among the documents, and potential enhancements are covered in the last section. 2022 IEEE. -
A Low Voltage and Low Power Analog Multiplier
In this research work, a low voltage analog multiplier has been realized through the utilization of a flipped voltage follower (FVF). The multiplier is characterized by its capacity to function at low power while exhibiting high gain. The exclusive use of transistors in its implementation renders it highly appropriate for fully integrated circuit applications. The multiplier has been developed using a supply voltage of 500 mV and an operating frequency of 25 KHz. The design consumes power of 8.23 uW. Moreover, a comparative study between the proposed multiplier and the conventional gilbert multiplier is presented in the paper. All simulations and layout designs have been conducted through the virtuoso analog design environment (ADE) of Cadence at 45 nm CMOS technology. 2023 IEEE. -
Envisaging an Intelligent Blockchain Network by Intelligence Sharing
Blockchain Technology is gaining popularity throughout various industry verticals due to its data decentralization and tamper-evident nature. Machine Learning (ML) is all about embedding a learning capability to computing machines so that the machine can learn based on historical data in a way how human beings learn things. An important part of ML is the process of learning which needs humongous processing capability and hence it is time-consuming. Significant benefits have been predicted from the integration of these two technologies. Making a complete blockchain network intelligent in a simple and efficient way is a major challenge. In this work, a Multi Layer Perceptron (MLP) model is implanted in every node of the blockchain network. An efficient technique is proposed to make an intelligent blockchain network in minimum possible time and using minimum processing power. During the network formation, every node of the network has knowledge of the model architecture. At some point in time, the model of the randomly selected node gets trained. After completion of the training of that node, the intelligence is replicated to the entire network. 2022 IEEE. -
Factor Analysis for Portfolio Returns: Investigating How Macroeconomic Factors Impact the Performance of the equity Portfolio
This paper investigates the complex relationship between macroeconomic factors and equity portfolio performance using regression analysis. In today's volatile financial environment, it emphasizes the importance of understanding how variables such as interest rates, inflation, money supply and GDP influence investment outcomes. Exact statistical techniques and historical data from a specific time period are used to uncover hidden factors affecting portfolio returns, with a particular focus on interest rates, inflation, money supply, and GDP. The goal of the research is to provide a comprehensive understanding of how these macroeconomic factors influence the equity investments. 2024 IEEE. -
Effect of annealing and oxygen partial pressure on the RF sputtered WO3 thin films for electrochromic applications
the electrochromic thin layer of Tungsten trioxide (WO3) was RF sputtered on FTO (fluorine-doped tin oxide) slide. In a reactive Ar + O2 gas environment with varying oxygen partial pressures, the deposition continued. The samples were air annealed at 400 C for 2 h after being deposited at room temperature. SEM, XRD, UVVisible spectrometer, and electrochemical analyzer characterization methods were employed to analyze the surface, structural morphology, optical, and electrochromic behaviour of the deposited material after annealing. The Optical Bandgap and Transmittance were found to be of a higher value for air annealed samples than RT deposited samples because RT deposited samples are amorphous whereas air annealed samples exhibit crystalline nature with Oxidation, reduction peak currents variation with respect to the temperature. 2021 -
Glancing angle sputter deposited tungsten trioxide (WO3) thin films for electrochromic applications
The columnar growth angle-dependent tungsten oxide (WO3) thin films were grown by using the Glancing angle sputter deposition (GLAD) technique with varying different substrate angles (00, 700, 750, and 800) on Fluorine-doped tin oxide (FTO) and Corning glass (CG) corning glass substrates at room temperature. The surface morphology, crystallographic structure, optical, and electrochemical properties were determined using X-ray diffraction (XRD), Field emission scanning electron microscopy (FE-SEM), UltravioletVisible(UVVis) spectrometer, and electrochemical analyzer, respectively. The structural properties reveal that the films are amorphous in nature. FE-SEM studies observed the columnar growth of the nano-rods and surface porosity. The optical transmittance of the deposited films was decreased from 83 to 78%, and the optical bandgap decreased from 3.08 to 2.88eV with increasing GLAD angle. The electrochemical studies reveal that the GLAD angle influenced the coloration efficiency (CE). The highest CE of 32cm2/C at 600nm and highest Diffusion coefficient (DC) of 6.529 109 cm2s?1 of the films was observed for the films deposited at an angle of 750. 2022, The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature. -
Sputter deposited tungsten oxide thin films and nanopillars: Electrochromic perspective
Tungsten oxide (WO3) thin films and nano pillars were grown on FTO and corning substrates by using DC magnetron sputtering. Structural properties, surface morphology, optical properties, and electrochromic properties were systematically characterized by using SEM, XRD, UVVis Spectrometer, and Electrochemical Analyser respectively. Increased oxygen partial pressure resulted a rise in the optical transmittance from 72% to 89% at a wavelength of 600 nm. Moreover, coloration efficiency was also found to vary with partial pressures for both planar and glad from 30.48 cm2C-1 to 78.36 cm2C-1. We observe that glad deposited nano pillars showing higher coloration efficiency as compared to the planar thin film. The coloration efficiency found for the planar thin film and nano pillars at optimized partial pressure are 37.04 cm2C-1 and 78.36 cm2C-1 respectively. A strong influence of oxygen partial pressure and surface to volume ratio has been observed on the coloration efficiency, which can play a major role in the electrochromic application. 2022 Elsevier B.V. -
On ion transport during the electrochemical reaction on plane and GLAD deposited WO3 thin films
Tungsten oxide thin films were deposited on FTO and Corning glass substrates on Plane and GLAD (75) using DC magnetron sputtering and characterized using SEM, XRD, UVVis spectrophotometer, and Electrochemical analyzer systematically. Further, a comparative analysis was carried out in which it was observed that the result of surface morphology for plane showed the denser and GLAD showed nanopillars deposition. The amorphous nature of the sample was evident from XRD analysis. Optical transmittance was between 87% and 81% for both plane and GLAD. The Electrochemical studies showed the diffusion coefficient of H+ ions are more compared to Li+ ions for both plane and GLAD and Coloration efficiency was calculated at the scan rates of 10, 30, and 50 mV/s at the wavelength of 500 to 600 nm. 2021 -
Simulation and fabrication of tungsten oxide thin films for electrochromic applications
Electrochromics is the emerging technology that is used in sunlight control window glazing for buildings, automobiles and it can also control indoor climate through smart windows. Electrochromism is the mutable change in optical properties of an electrochromic material caused by redox reactions due to the application of voltage. Easy intercalating the H + ions on a dense electrochromic material (WO3) is the most important parameter as far as the reaction kinetics is concerned. The goal of our work is to improve the electrochemical response of electrochromic material by constructing nano-pillars rather than using dense electrochromic materials. Electrochemical performance of both the dense (planar) and porus (nano pillars) structures were simulated and experimentally proved with a systematic discussion in the present work. It is proven and shown here the increase in the electrochemical kinetics through easy diffusion of ions into the nanostructured electrochromic material. 2022 Elsevier B.V. -
FO-DPSO Algorithm for Segmentation and Detection of Diabetic Mellitus for Ulcers
In recent days, the major concern for diabetic patients is foot ulcers. According to the survey, among 15 people among 100 are suffering from this foot ulcer. The wound or ulcer found which is found in diabetic patients consumes more time to heal, also required more conscious treatment. Foot ulcers may lead to deleterious danger condition and also may be the cause for loss of limb. By understanding this grim condition, this paper proposes Fractional-Order Darwinian Particle Swarm Optimization (FO-DPSO) technique for analyzing foot ulcer 2D color images. This paper deals with standard image processing, i.e. efficient segmentation using FO-DPSO algorithm and extracting textural features using Gray Level Co-occurrence Matrix (GLCM) technique. The whole effort projected results as accuracy of 91.2%, sensitivity of 100% and specificity as 96.7% for Nae Bayes classifier and accuracy of 91.2%, sensitivity of 100% and sensitivity of 79.6% for Hoeffding tree classifier. 2023 World Scientific Publishing Company. -
Food innovation adoption and organic food consumerism-a cross national study between Malaysia and Hungary
In order to meet the rising global demand for food and to ensure food security in line with the United Nations Sustainable Development Goal 2, technological advances have been introduced in the food production industry. The organic food industry has benefitted from advances in food technology and innovation. However, there remains skepticism regarding organic foods on the part of consumers, specifically on consumers acceptance of food innovation technologies used in the production of organic foods. This study measured factors that influence consumers food innovation adoption and subsequently their intention to purchase organic foods. We compared the organic foods purchase behavior of Malaysian and Hungarian consumers to examine differences between Asian and European consumers. The findings show food innovation adoption as the most crucial predictor for the intention to purchase organic foods in Hungary, while social lifestyle factor was the most influential in Malaysia. Other factors such as environmental concerns and health consciousness were also examined in relation to food innovation adoption and organic food consumerism. This paper discusses differences between European and Asian organic foods consumers and provides recommendations for stakeholders. 2021 by the authors. Licensee MDPI, Basel, Switzerland. -
Monoclinic yttrium oxide quantum dots surface modified by biotin for bioimaging applications
Semiconductor nanoparticles or quantum dots are one of the central topics of interest in material science research due to its size dependent physical and chemical characteristics and applications in different areas from display to biomedical fields. This work reports the first-time synthesis of biotin functionalized monoclinic yttrium oxide quantum dots at low temperature and its application in live cell imaging. The presence of biotin was confirmed through FTIR measurements. HRTEM analysis confirmed the formation of small spherical quantum dots with an average size of 3.8 nm. Zeta potential measurements gave a negative surface charge of -26.9 mV confirming colloidal stability. The quantum dots show sharp absorption in the short UV region and PL experiments delivered defect related intense blue fluorescence emission. The material is nontoxic to both normal (L929) and cancer (MCF 7) cells and the live cell imaging experiments performed on MCF 7 cells show specific binding to the cells and presented bright fluorescence emission from the cells thus confirming the applicability of the material in both display industry and cancer cell imaging. 2023 Elsevier B.V. -
Folic Acid-Modified B-Type Y2O3:Eu3+ Quantum Dots: A Bright Approach to Fluorescence Imaging of Cancer Cells
Clinical applications of nanophosphors have gained extensive interest in research areas such as bioimaging and targeted drug delivery. The development of nontoxic semiconductor quantum dots (QDs), which can replace the conventional fluorescent probes, can bring significant developments in the bioimaging industry. This work reports the synthesis of monoclinic Y2O3:Eu QDs, without and with surface functionalization using PEG/folic acid at low temperature and its application in live cancer cell imaging. The synthesized quantum dots show sharp absorption in the short UV region and an intense red emission at 614 nm. Concentration-dependent optical properties are studied in detail, and color purity is measured. Transmission electron microscopy substantiates the monoclinic structure, crystalline nature, and the lower particle dimensions essential for the biological applications. The surface-modified sample is characterized for its structural and luminescence properties. Biocompatibility was ensured by performing MTT Assay on L6 skeletal muscle cell lines (normal) and MCF 7 cell lines (cancer) for the samples without and with surface modification, respectively. Fluorescence detection experiments on SKMEL cells using an uncapped sample prove the suitability of the material as a fluorescent probe. The effect of surface functionalization on imaging results was established by carrying out fluorescence detection experiments on MCF 7 cells using PEG-folic acid-functionalized sample, which resulted in enhanced cell uptake, specific binding, and bright fluorescence emission. Thus, this work authenticates the suitability of the material to be used as a reliable nanophosphor and an efficient fluorescent probe for imaging cancer cells. 2024 American Chemical Society. -
Labelling of human breast cancer cells with PEG/biotin encapsulated B-type Y2O3: Eu nanophosphors for fluorescence detection
The development of non-toxic quantum dots (QDs) for fluorescence labelling of cancer cells can bring significant advancements in the disease detection. Such findings can effectively replace the conventional toxic fluorescent probes by virtue of its tunable optical characteristics. Through this work, we present the development of an efficient fluorescent probe based on B-type Y2O3: Eu QDs for labelling MCF 7 cell lines. The QDs surface was encapsulated by poly ethylene glycol (PEG) along with tumour targeting ligand, biotin. The luminescence capability of the QDs were established through photoluminescence experiments. The QDs were tested to be non-toxic through MTT assay. Fluorescence detection experiments on MCF 7 cells using the nanophosphor established the material's potential to serve as an efficient probe for cancer cell detection. 2024 Elsevier B.V. -
A critical review focussing on the synthesis and applications of monoclinic yttrium oxide nanophosphor
Research on monoclinic Y2O3 has been limited, not because of a lack of potential applications, but rather due to challenges associated with synthesizing phase-pure material. The limited understanding of the material and its properties has hindered researchers from further exploring this compound. Some studies suggest that the B-type polymorph of Y2O3 exhibits superior performance compared to its cubic counterpart. Additionally, there are reports indicating the existence of simple synthesis techniques that could potentially overcome the material's significant disadvantage highlighted by many researchers, namely, complex synthesis routes. To date, no comprehensive reports have summarized the key findings related to B-type Y2O3. In this effort, we aim to provide an exhaustive overview of research conducted on this polymorph. This includes an examination of diverse synthesis techniques employed by researchers, theoretical studies conducted on the material, an exploration of its luminescence properties, and an overview of various applications studied thus far. 2024 Elsevier Ltd -
Persistent Luminescence and in Vivo Bioimaging
In vivo bioimaging encompasses the non-invasive visualization of internal cells or organs within the human body, facilitating the real-time monitoring of dynamic biological processes. This form of bioimaging holds paramount significance within clinical domains due to its capacity to facilitate early disease detection, notably in cases of life-threatening conditions such as cancer. Although established imaging modalities like ultrasound, magnetic resonance imaging, and fluorescence imaging exist, the quest for innovative imaging probes with enhanced visibility to provide high-resolution images remains an active area of research. The introduction of persistent luminescent nanoprobes, characterized by their unique afterglow luminescence property, presents an exciting avenue in the realm of bioimaging. These nanoprobes offer several advantages over traditional fluorescent probes, notably in their ability to surmount light attenuation challenges within biological tissues including issues such as autofluorescence and light scattering. The chapter offers a succinct introduction to two pivotal facets of fluorescence imaging, namely persistent luminescence and upconversion luminescence while elucidating the underlying mechanisms governing their luminescence behavior. Moreover, this chapter provides comprehensive insights into various fluorescence imaging techniques, encompassing near-infrared imaging, upconversion imaging, X-ray-activated luminescence imaging, persistent luminescence imaging, and various multimodal imaging techniques. The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024. -
Photoluminescence studies of non-toxic monoclinic yttrium oxide quantum dots synthesized at low temperature for live cell imaging applications
Synthesis of monoclinic Y2O3 remains a challenging task due to complex formation conditions such as high pressure or high temperature environments. Monoclinic yttria exhibits better photoluminescence characteristics compared to the cubic phase and hence can be a better host for nanophosphors. Reports are available predicting the stability of monoclinic phase at low temperature in extremely fine particles. But experimental preparation of this phase at low temperature is not yet reported. Here we report the first-time preparation of monoclinic Y2O3 at 90 C using simple laboratory hot air oven. The synthesized nanoparticles exhibit intense PL emission in the blue region and hence can find applications in display industry. The band structure calculations were carried out using density functional theory and the excitonic Bohr radius was estimated using the electron as well as hole effective masses determined from band structure. The cytotoxicity studies reveal non-toxic nature the particles. The fluorescence imaging experiments show that the material is capable of emitting blue fluorescence in L6 skeletal cell lines and it ensures the applicability of this material in the biomedical field. 2022 Elsevier Ltd and Techna Group S.r.l. -
Sesquiterpenoid-rich Java Ginger rhizome extract prompts autophagic cell death in cervical cancer cell SiHa mainly by modulating cellular redox homeostasis
Java Ginger or Curcuma zanthorrhiza Roxb. has long gained focus among tribal people of Java, for its medicinal properties mainly against gynaecological challenges. The present study aims to identify the most potent phytocompound present in the extract and determine primary mode of action accountable for cytotoxic activity of Curcuma zanthorrhiza rhizome extract against HPV16-positive SiHa cervical cancer cells. The phytochemically-rich extract of rhizome (CZM) was capable to inhibit proliferation of target cells in a dose-dependent manner with an IC50 of 150?g/ml. Dysregulation of intercellular antioxidant defence system resulted to surges in ROS and RNS level, increased calcium concentration and compromised mitochondrial membrane potential. Nucleus got affected, cell cycle dynamics got impaired while clonogenicity and migration ability diminished. Expression of viral oncogenes E7 and E6 decreased significantly. Accumulation of toxic cell metabolite and decrease in level of essential ones continued. Finally, alteration in PI3K/AKT/mTOR signalling route was followed by onset of autophagic cell death concomitant with the upregulated expression of Beclin1, Atg5-12 and LC3II. Curcumin and a novel crystal as well as few phyto-fractions were isolated by column chromatography. Of these, curcumin was found to be most potent in inducing cytotoxicity in SiHa while two other fractions also showed significant activity. Thus, CZM acted against SiHa cells by inducing autophagy that commences in compliance to the changes in PI3K/AKT/mTOR pathway mainly in response to oxidative stress. To the best of our knowledge this is the first report of Curcuma zanthorrhiza Roxb. inducing autophagy. 2022, King Abdulaziz City for Science and Technology. -
Involvement of chalcones and coumarins in environmental stress tolerance
Plants are invariably subjected to various environmental stresses that hinder their normal growth and development, which leads to decreased plant productivity and yield. To combat the detrimental effects of such abiotic and biotic stresses, plants have developed diverse mechanisms and one of the prominent ones includes the production of secondary metabolites like phenolic, alkaloids, terpenes, etc. Secondary metabolites serve as major components of the plant stress responses. Chalcones (1,3-diaryl-2-propen-1-one) and coumarins (1,2-benzopyrone) are precursors of flavonoids, a common secondary metabolite of plants that provide a beneficial role during oxidative and biotic stress. Apart from protection, coumarins have certain roles in promoting or inhibiting plant growth, affecting cell division and differentiation and auxin metabolism. These compounds are also known to possess therapeutic properties such as anti-inflammatory, anti-microbial, anti-cancer, and cytotoxic effects when isolated from plants. Besides, chalcones and coumarins have allelopathic effects and protect plants against herbivory. Owing to excellent ROS scavenging properties, chalcones, coumarins, and their derivatives are extensively employed as agents to alleviate adversities associated with abiotic stresses like osmotic, heat, and cold stress, and in defense against pathogen invasion. The application of these secondary metabolites to mitigate atrocities of environmental stress in plants is an interesting and concurrent area of investigation. This chapter highlights the structural and functional details of chalcones and coumarins and their implications in ameliorating environmental stress in plants. 2024 Apple Academic Press, Inc. All rights reserved.