Browse Items (5511 total)
Sort by:
-
High surface area Nanoflakes of P-gC3N4 photocatalyst loaded with Ag nanoparticle with intraplanar and interplanar charge separation for environmental remediation
The photocatalytic performance of gC3N4 is majorly restricted by insufficient collection of photogenerated charges on the surface during reaction due to highly dense stacking of lamellar structures with lateral size ranging in microns. This deficiency can be overcome by forming thin nanoflakes by systematically breaking the weak bonds that hold the gC3N4 framework without destroying the basic heptazine unit. With this aim, herein, a combination of three different strategies was implemented to design and develop, Ag-loaded and P-doped gC3N4 nanoflakes (Ag3-P1-NF-gC3N4). Using a systematic synthesis method, bulk gC3N4 was first converted into thin nanosheets, followed by fragmentation into nanoflakes, with a planar size up to 100 nm. P doping to replace the corner C atoms in the gC3N4 matrix (forming P[sbnd]N bonds) and intercalation of plasmonic Ag nanoparticles within the interlayers also assists in the bifurcation of the stacked layers and formation of nanoflake morphology. These strategies result in a significant increase in BET surface area to ?196 m2/g from 12 m2/g of bulk gC3N4. Improved inter-planar and intra-planar charge mobility was recorded as a result of the reduced sizes. Doping with P also causes higher absorption of the visible spectrum in gC3N4 while the formation of heterojunction with Ag nanoparticles induces efficient separation of photo-generated charges. All these promoting photo-physical properties lead to an outstanding photocatalytic activity towards degradation of aqueous pollutants with reaction rates ?20 times higher than bulk gC3N4. Complete mineralization of the pollutant and formation of non-toxic byproducts was also confirmed with suitable chromatography techniques. 2020 Elsevier B.V. -
High-affinity binding of celastrol to monomeric ?-synuclein mitigates invitro aggregation
?-Synuclein (?Syn) aggregation is associated with Parkinsons disease (PD). The region ?Syn36-42 acts as the nucleation 'master controller and ?Syn1-12 as a secondary nucleation site. They drive monomeric ?Syn to aggregation. Small molecules targeting these motifs are promising for disease-modifying therapy. Using computational techniques, we screened thirty phytochemicals for ?Syn binding. The top three compounds were experimentally validated for their binding affinity. Amongst them, celastrol showed high binding affinity. NMR analysis confirmed stable ?Syn-celastrol interactions involving several residues in the N-terminus and NAC regions but not in the C-terminal tail. Importantly, celastrol interacted extensively with the key motifs that drive ?Syn aggregation. Thioflavin-T assay indicated that celastrol reduced ?Syn aggregation. Thus, celastrol holds promise as a potent drug candidate for PD. Communicated by Ramaswamy H. Sarma. 2023 Informa UK Limited, trading as Taylor & Francis Group. -
High-Movement Human Segmentation in Video Using Adaptive N-Frames Ensemble
A wide range of camera apps and online video conferencing services support the feature of changing the background in real-time for aesthetic, privacy, and security reasons. Numerous studies show that the Deep-Learning (DL) is a suitable option for human segmentation, and the ensemble of multiple DL-based segmentation models can improve the segmentation result. However, these approaches are not as effective when directly applied to the image segmentation in a video. This paper proposes an Adaptive N-Frames Ensemble (AFE) approach for high-movement human segmentation in a video using an ensemble of multiple DL models. In contrast to an ensemble, which executes multiple DL models simultaneously for every single video frame, the proposed AFE approach executes only a single DL model upon a current video frame. It combines the segmentation outputs of previous frames for the final segmentation output when the frame difference is less than a particular threshold. Our method employs the idea of the N-Frames Ensemble (NFE) method, which uses the ensemble of the image segmentation of a current video frame and previous video frames. However, NFE is not suitable for the segmentation of fast-moving objects in a video nor a video with low frame rates. The proposed AFE approach addresses the limitations of the NFE method. Our experiment uses three human segmentation models, namely Fully Convolutional Network (FCN), DeepLabv3, and Mediapipe. We evaluated our approach using 1711 videos of the TikTok50f dataset with a single-person view. The TikTok50f dataset is a reconstructed version of the publicly available TikTok dataset by cropping, resizing and dividing it into videos having 50 frames each. This paper compares the proposed AFE with single models and the Two-Models Ensemble, as well as the NFE models. The experiment results show that the proposed AFE is suitable for low-movement as well as high-movement human segmentation in a video. 2022 Tech Science Press. All rights reserved. -
High-Performance ?-cyclodextrin-Ti3C2Tx MXene-Based Electrochemical Sensor for the Detection of Neurological Disorder Biomarker
In this work, the ?-cyclodextrin-MXene (?-CD-MXene) composite was employed as a modifier for carbon fiber paper (CFP) electrodes and quantification of L-methionine (L-Met). The ?-CD-MXene composite was prepared by hydrothermal synthesis route by adding ?-CD and Ti3C2Tx MXenes obtained via the Minimally intensive layer delamination technique. Cyclic voltammetry (CV) and Differential Pulse Voltammetry (DPV) were conducted to study the influence of scan rate and pH on the electrooxidation of L-Met studies using the ?-CD-MXene/CFP electrode. The layered structure of the exfoliated Ti3C2Tx MXenes with charge transfer efficiency in combination with the host-guest interaction ability of ?-CD enhances the electrooxidation of L-Met. The ?-CD-MXene/CFP electrode showcased high sensitivity, reproducibility, and stability, and the anodic peak currents were in linearity with L-Met concentration within the range of 0.09-540 ?M and LOD of 0.03 ?M under various optimized conditions. In addition, the developed sensor showcases highly selective and non-interfering sensing of L-Met. 2024 The Electrochemical Society (ECS). Published on behalf of ECS by IOP Publishing Limited. -
High-performance reconfigurable FET for a simple variable gain buffer amplifier design
Design and simulation of variable gain analog buffer amplifier using single gate reconfigurable field-effect transistor (SG-RFET) with strained silicon channel are proposed. The design simplicity makes SG-RFET device a potential candidate compared to the multi-gate RFET devices. The gain of the proposed configuration is varied by tuning the feedback voltage. The voltage gain of the proposed configuration can be tuned from 0.97V/V to 5V/V with an output load of 1 k?. The operational transconductance amplifier (OTA) using the SG-RFET device is used in the proposed buffer amplifier design. 2021 Informa UK Limited, trading as Taylor & Francis Group. -
Highly Efficient Photocatalytic Conversion of Amine to Amide and Degradation of Methylene Blue Using BiOClTiO2 Nano Heterostructures
Abstract: Facile green synthesis of BiOClTiO2 was done using combustion technique by Ixora coccinea leaf extract as fuel source. The said material was characterized using XRD, SEM, EDX, HRTEM, SAED, FTIR, and UV-DRS. The particle size was found to be approximately 60nm and a crystallite size of 0.3nm from TEM. The photocatalytic activity of the material was found out using photoluminescence studies, dye degradation and photocatalytic organic conversion. The material showed excellent dye degradation capacity for methylene blue with 80% of the dye degraded under 3hrs. The stabilisation of electronhole pair by the heterostructure gave it the ability to perform easy degradation. The degradation kinetics have also been studied. It also showed an excellent organic conversion property with formylation yield reaching up to 96% and total conversion of the reactant molecule. The material is a potent photocatalyst due to its great efficiency and can have a remarkable role in the synthesis of important organic molecules and detoxification of environment. Graphical Abstract: The heterostructure catalyses the conversion of amine to amides and mineralizes methylene blue under visible light condition. [Figure not available: see fulltext.]. 2020, Springer Science+Business Media, LLC, part of Springer Nature. -
Highly Luminescent MOF and Its in Situ Fabricated Sustainable Corn Starch Gel Composite as a Fluoro-Switchable Reversible Sensor Triggered by Antibiotics and Oxo-Anions
Frequent use of antibiotics and the growth of industry lead to the pollution of several natural resources which is one of the major consequences for fatality to human health. Exploration of smart sensing materials is highly anticipated for ultrasensitive detection of those hazardous organics. The robust porous hydrogen bonded network encompassing a free-NH2 moiety, Zn(II)-based metal-organic framework (MOF) (1), is used for the selective detection of antibiotics and toxic oxo-anions at the ppb level. The framework is able to detect the electronically dissimilar antibiotic sulfadiazine and nitrofurazone via fluorescence "turn-on"and "turn-off"processes, respectively. The antibiotic-triggered reversible fluoro-switching phenomena (fluorescence "on-off-on") are also observed by using the fluorimetric method. An extensive theoretical investigation was performed to establish the fluoro-switching response of 1, triggered by a class of antibiotics and also the sensing of oxo-anions. This investigation reveals that the interchange of the HOMO-LUMO energy levels of fluorophore and analytes is responsible for such a fluoro-switchable sensing activity. Sensor 1 showed the versatile detection ability which is reflected by the detection of a carcinogenic nitro-group-containing drug "roxarsone". In view of the sustainable environment along with quick-responsive merit of 1, an in situ MOF gel composite (1@CS; CS = corn starch) is prepared using 1 and CS due to its useful potential features such as biocompatibility, toxicologically innocuous, good flexibility, and low commercial price. The MOF composite exhibited visual detection of the above analytes as well as antibiotic-triggered reversible fluoro-switchable colorimetric "on-off-on"response. Therefore, 1@CS represents a promising smart sensing material for monitoring of the antibiotics and oxo-anions, particularly appropriate for the real-field analysis of carcinogenic drug molecule "roxarsone"in food specimens. 2022 American Chemical Society. -
Highly luminescent ZnS:Mn quantum dots capped with aloe vera extract
This study demonstrates the optical properties of ZnS:Mn2+ qquantum dots synthesized by simple and eco-friendly chemical precipitation method using aloe vera (AV) extract as the stabilizing agent. The nanoparticles have been characterized by transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, diffuse reflectance spectroscopy (DRS), photoluminescence (PL) and time-resolved PL spectroscopy. Increase in band gap energy with decrease in particle size was observed from DRS studies due to quantum confinement effect. Dominant yellow emission was observed from characteristic 4T1?6A1 transitions of the Mn2+ions in the ZnS:Mn/AV nanoparticles. The results provide insight to the quantum confinement effect that occur and how it affect decay life time of the ZnS:Mn2+/AV nanoparticles. 2020 Elsevier Ltd -
Highly mixed high-energy d-orbital states enhance oxygen evolution reactions in spinel catalysts
Design, synthesis, and engineering of electrocatalysts for the oxygen evolution reaction (OER) are essential for attaining desirable electrocatalytic performance towards practical implementation. Emerging spinel-type OER catalysts have not reached the desirable activity and durability, thus demanding critical research to advance the field. To achieve enhanced OER performance for spinel-type OER catalysts, we present an efficient strategy of electronic structure modulation of central metal atoms. Modulation of the electronic properties of the Zn and Co atoms through the counter anionic components (O, S, and Se) regulates the adsorption of oxygen intermediates and thus enhances OER activity, which is systematically demonstrated using Density Functional Theory (DFT) calculation. Although the zinc cobalt selenide catalyst showed the less pronounced trigonal distortion, the mixing of eg orbitals with selenium accounts for the experimentally observed enhancement in OER activity. The result is, in contrast to the benchmark catalyst made of RuO2, ZnCo2Se4@rGO demonstrated lower OER overpotential (?10 = 302 mV) and Tafel slope (58 mV dec?1) as well as greater durability at 10 mA cm?2 for 50 h. The implementation of this strategy in several spinel-type catalysts could improve their electrocatalytic performance. 2023 Elsevier B.V. -
Highly secured authentication and fast handover scheme for mobility management in 5G vehicular networks
The Fifth Generation (5 G) networks exhibit high flexibility and diversity in their design and deployment strategies. Transitions between base stations (BSs), heterogeneous networks (HetNets) and other cellular networks provide significant vulnerabilities and expose users to substantial risks associated with cybersecurity attacks. This article evaluates current handover authentication methods in the context of 5 G networks while proposing a set of security criteria for handover authentication. This study presents a novel authentication technique called SHK (Secure Handover Key) that utilizes SDNs (Software Defined networks). The proposed scheme integrates recycled lightweight dynamic key cryptography and combines security features such as perfect forward secrecy and robustness to leakages. The significance of the proposed approach is assessed in terms of computations, communications, signals, and energy costs on 5 G mobility applications and Vehicular Communication Networks (VCNs). The scheme employed in this study demonstrates enhanced security measures and improved changeover performance compared to conventional schemes. 2024 Elsevier Ltd -
Highly selective derivative spectrophotometric determination of palladium(II) in hydrogenation catalysts and alloy samples
A simple, selective and sensitive derivative spectrophotometric method has been developed for the determination of palladium(II) using a newly synthesised reagent diacetylmonoxime-(p-anisyl)-thiosemicarbazone in acetic acid medium. The molar absorptivity and Sandell's sensitivity of the coloured species are 3.8 104 L mol-1 cm-1 and 2.8 ng cm-2, respectively. Beer's law is obeyed between 0.2-2.0 ?g mL-1 of Pd(II) at 440 nm. The stoichiometry of the complex is found to be 1:2 (metal:ligand). Calibration graph for the first order derivative spectrophotometric determination of palladium(II) is derived by measuring derivative amplitudes at 480 nm with a linear range 0.15-2.6 ?g mL-1. The metal ions, which are normally associated with palladium in mineral and alloy samples, do not interfere. The proposed method has been successfully applied for the trace level determination of palladium in hydrogenation catalysts and some synthetic mixtures. -
Highly selective first order derivative spectrophotometric determination of osmium(VIII) using anthranilic acid as a chromogenic reagent
A simple, selective and sensitive spectrophotometric method has been developed for the determination of osmium(VIII) using anthranilic acid as a reagent in the presence of Triton X-100. The molar absorptivity and Sandells sensitivity of the violet coloured species are 3.03 104L mol-1cm-1 and 3.5 ng cm-2 respectively. Beers law is obeyed between 0.5-5.5 ?g mL-1 of Os(VIII) at 500 nm. The stoichiometry of the complex is found to be 1:2 (metal: ligand). Calibration graph for the first order derivative spectrophotometric determination of Os(VIII) is derived by measuring derivative amplitudes at 525 nm with a linear range 0.25-5.5 ?g mL-1. The detection limit and quantitation limit of first order derivative spectrophotometry are found to be 0.075 and 0.25 ?g mL-1, respectively.1 1The metal ions, which are normally associated with osmium in catalysts and alloy samples, do not interfere. The proposed method has been successfully applied for the trace level determination of osmium in various synthetic mixtures containing commonly associated metal ions and corresponding to the alloy composition. 2015, National Institute of Science Communication and Information Resources (NISCAIR). All rights reserved. -
Highly selective first order derivative spectrophotometric determination of osmium(VIII) using anthranilic acid as a chromogenic reagent /
Indian Journal Of Chemical Technology, Vol.22, Issue 5, pp.234-240, ISSN No: 0975-0991 (Online), 0971-457X (Print). -
Highly Surface Active Anisotropic Silver Nanoparticles as Antimicrobial Agent Against Human Pathogens, Mycobacterium smegmatis and Candida albicans
Rapid synthesis of anisotropic silver nanoparticles via cost-effective, non-hazardous, and eco-friendly methods using naturally available gums are of greater significance as their chemical synthesis is associated with high toxicity. This study aims to synthesize highly surface-active anisotropic silver nanoparticles and evaluate their antimicrobial efficacy against human pathogens, Mycobacterium smegmatis and Candida albicans. Anisotropic silver nanoparticles were synthesized using silver nitrate as the metal precursor and gum arabic as the template. The synthesized silver nanoparticles were characterized by UV-visible spectroscopy, fourier transformation infra-red (FTIR) spectroscopy, dynamic light scattering (DLS) analysis, high-resolution transmission electron microscopy and selected area electron diffraction (HRTEM-SAED) analysis and thermogravimetric analysis (TGA). TEM analysis showed the anisotropy and monodispersed nature of silver nanoparticles with an average size of less than 20 nm. The antibacterial and antifungal properties of the anisotropic silver nanoparticles were also studied keeping rifampicin and fluconazole as the reference. The minimum inhibitory concentration (MIC) was found to be 1 mM silver nanoparticles for both M. smegmatis and C. albicans. Synthesized anisotropic silver nanoparticles can be used as an alternative to antibiotics to treat the infections caused by M. smegmatis and C. albicans. Further, the effect of silver nanoparticles on haemolytic activity was also studied. 2021 Wiley-VCH GmbH -
Hindu nationalism and media violence in news discourses in India
The mainstream media and communication discourses in India in the present times engender media violence embedded in the dominant productions of Hinduism together with aspirations for neoliberal development. The media violence engenders indigenous forms of racism and colonialism. This article attempts to examine the nature of these productions through critical theories of postcoloniality and decolonial approaches put into conversation with theories of journalism. Through the examination of the instances of selective silencing of journalistic voices, and erasures embedded within the journalistic practices, this article argues for critical theories of press freedom. The productions of racial superiority and internal colonialism in India only begin to make sense when read together with the interplays of religion, class, caste, and global reach of the privileged sections of Indian society, namely the civil society. Against the backdrop of the historical role of the press in India in freedom struggle against colonial rule, the history of press censorship after independence, the civil society voices that are amplified in the neoliberal restructuring of news media, and the Dalit movements that expose the Brahminical dominance in the imaginary of the Indian culture, the meanings of race and coloniality in India unfold. 2020 National Communication Association. -
Histopathological and Toxicological Studies on Zebra Fish Using White-Fruited and Green-Fruited Varieties of Momordica charantia
Momordica charantia is well known for its medicinal properties. It has exhibited various pharmacological activities, such as antidiabetic, anti-inflammatory, and antimicrobial activities. Although this plant is used worldwide as a vegetable and medicinal ingredient in herbal medicines, its toxicity studies have not been conducted to date. This study attempts to understand its toxicity. The present study examined the activity of two enzymes, acetylcholinesterase and succinate dehydrogenase, as well as histopathological variations in the liver, intestine, and gills of zebrafish. The results of the acetylcholinesterase assay showed that the concentrations of 40 mg/L and 60 mg/L of the four extracts (leaf and fruit extracts of both varieties) exhibited increased enzyme activity. Interestingly, the leaves of the green fruit variety at a concentration of 60 mg/L showed the highest activity, with a value of 2.824 0.0682 micromoles/min compared to the control value of 1.8347 0.0046 micromoles/min. On the other hand, the succinate dehydrogenase assay revealed that the concentrations of 40 mg/L and 60 mg/L of the extracts decreased the enzyme activity. The highest inhibition was observed in the concentration of 60 mg/L of the leaves of the white-fruited variety and the green-fruited variety, with values of 1.884 0.0482 micromoles/min compared to the control value of 2.747 0.0046 micromoles/min. The studies on histopathological changes also demonstrated abnormalities in the brain, liver, intestine, and gills of zebrafish after the exposure to the extracts of M. charantia. The severity of the damage varied from low to high concentraions. In general, this study sheds light on the safety profile of Momordica charantia and highlights its potential toxicity in animal models. The findings suggest that more research is needed to fully understand the toxicity of this plant and its implications for human use. 2024 Jobi Xavier et al. -
History of gestational diabetes mellitus, self-efficacy and coping in postpartum women: A pilot study
The present study investigates whether the history of gestational diabetes mellitus (GDM) influences self-efficacy and coping among postpartum women. Purposive sampling technique was used to collect data from 100 postpartum women, 50 with a history of GDM and 50 without. The General Perceived Self-Efficacy Scale was used to measure the self-efficacy of the participants. The Brief COPE developed by Carver was used to measure coping. A Mann-Whitney U-test showed postpartum women with a history of GDM are higher in self-efficacy and coping than those without such a history. Even though self-efficacy showed a relationship to coping, the two groups differed in the use of coping strategies. 2018 by the Research Institute of Asian Women, Sookmyung Women's University. All rights reserved. -
HMOSHSSA: a novel framework for solving simultaneous clustering and feature selection problems
In real-life scenarios, information about the number of clusters is unknown. Due to this, clustering algorithms are unable to generate the valuable partitions. Beside this, the appropriate and optimal number of features is also required to produce the good quality clusters. The selection of optimal number of clusters and feature is a challenging task in the clustering. To resolve these problems, an automatic multi-objective-based clustering approach called HMOSHSSA is proposed in this paper. In HMOSHSSA, the spotted hyena and salp swarm algorithms are hybridized to obtain a better trade-off between these algorithms intensification and diversification capabilities. Two novel concepts for encoding and threshold setting are incorporated in the HMOSHSSA. The encoding scheme is used to choose the optimal number of clusters and features during the optimization process. The variance of dataset is used for setting the threshold values for both clusters and features. A novel fitness function is proposed to improve the optimization process. The suggested algorithms performance is evaluated using eight well-known real-world datasets. The statistical significance of HMOSHSSA is measured through t-tests. Results reveal that the proposed approach is able to detect the optimal number of clusters and features from a given dataset without user intervention. This approach is also deployed for solving microarray data analysis and image segmentation problems. HMOSHSSA outperformed the other considered algorithms in terms of performance measures. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024. -
Hockey among the Indigenous Tribes of Sundargarh, Odisha
[No abstract available] -
Homomorphic DNA Security in IoT Edge Data
The Internet of Things (IoT) based intelligent medical system possesses sensitive and private patient data. Most data relates to the patient's medical records and highly sensitive information. For this reason, safety and confidentiality of information are crucial. The preservation of patient privacy when sharing medical data is the primary concern of this study. Due to their excellent performance, biological notations based on deoxyribonucleic acid (DNA) are becoming increasingly admired for guaranteeing encryption and image protection. This paper proposes lightweight homomorphic with DNA-based medical image encryption (HDNA_MIE) for heterogeneous IoT in edge computing. The proposed approach contains two steps: In the first step, the secure DNA keys are generated using lightweight operations such as shifting and Josephus ring-based permutation (JRP). In the second step, the lightweight homomorphic cryptographic algorithm with DNA sequence-based encryption algorithm is suggested for secure encryption. The suggested strategy is evaluated using computational time and statistical analysis with several measures to determine its efficacy. The experimental findings of the proposed strategy exhibited a high level of security and a noticeable enhancement in the Number of Pixels Change Rate (NPCR), Unified Average Changing Intensity (UACI) and encryption processing time. The experiment outcomes demonstrate that our technique may be applied to highly confidential image encryption. 2024, Iquz Galaxy Publisher. All rights reserved.