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An Anomaly Detection Framework for Twitter Data
An anomaly indicates something unusual, related to detecting a sudden behavior change, and is also helpful in detecting irregular and malicious behavior. Anomaly detection identifies unusual events, suspicious objects, or observations that differ significantly from normal behavior or patterns. Discrepancies in data can be observed in different ways, such as outliers, standard deviation, and noise. Anomaly detection helps us understand the emergence of specific diseases based on health-related tweets. This paper aims to analyze tweets to detect the unusual emergence of healthcare-related tweets, especially pre-COVID-19 and during COVID-19. After pre-processing, this work collected more than 44 thousand tweets and performed topic modeling. Non-negative matrix factorization (NMF) and latent Dirichlet allocation (LDA) were deployed for topic modeling, and a query set was designed based on resultant topics. This query set was used for anomaly detection using a sentence transformer. K-means was also employed for clustering outlier tweets from the cleaned tweets based on similarity. Finally, an unusual cluster was selected to identify pandemic-like healthcare emergencies. Experimental results show that the proposed framework can detect a sudden rise of unusual tweets unrelated to regular tweets. The new framework was employed in two case studies for anomaly detection and performed with 78.57% and 70.19% accuracy. 2022 by the authors. -
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. -
Enzyme immobilization on biomass-derived carbon materials as a sustainable approach towards environmental applications
Enzymes with their environment-friendly nature and versatility have become highly important green tools with a wide range of applications. Enzyme immobilization has further increased the utility and efficiency of these enzymes by improving their stability, reusability, and recyclability. Biomass-derived matrices when used for enzyme immobilization offer a sustainable solution to environmental pollution and fuel depletion at low costs. Biochar and other biomass-derived carbon materials obtained are suitable for the immobilization of enzymes through different immobilization strategies. Environmental pollution has become an utmost topic of research interest due to an ever-increasing trend being observed in anthropogenic activities. This has widely contributed to the release of various toxic effluents into the environment in their native or metabolized forms. Therefore, more focus is being directed toward the utilization of immobilized enzymes in the bioremediation of water and soil, biofuel production, and other environmental applications. In this review, up-to-date literature concerning the immobilization and potential uses of enzymes immobilized on biomass-derived carbon materials has been presented. 2022 Elsevier Ltd -
CoFe2O4-APTES nanocomposite for the selective determination of tacrolimus in dosage forms: Perspectives from computational studies
An innovative and cost effective electrochemical sensor was fabricated to determine tacrolimus (TAC) in pharmaceutical samples. In the present study, cobalt ferrite nanoparticles (CFO) were synthesized hydrothermally using chitosan as the template and were further functionalized using (3-Aminopropyl) triethoxysilane (APTES). The synthesized CFO were characterized using various analytical techniques such as X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, vibrating sample magnetometry and high- resolution transmission electron microscopy. The CFO and CFO-APTES were further drop-casted on to the glassy carbon electrode (CFO-NH2/GCE) for the electrochemical determination of TAC. Under the optimum conditions, the CFO-NH2/GCE showed a very low detection limit of 0.03 nM with a high sensitivity of 21,448 ?A?M?1cm?2 and a wide linear TAC concentration range of 0.14 nM 75.83 nM. The proposed sensor showed good sensitivity, selectivity, reproducibility and stability for the sensing of TAC and this has been demonstrated by analysing TAC in different dosage forms. This is the first study to report the interaction of CFO-TAC and CFO-NH2-TAC at the electrode/electrolyte interface. To support the experimental findings qualitatively, extensive density functional theory simulations were carried out to study the interaction at the interface. Hence the proposed sensor is very selective and sensitive towards the detection of TAC. 2022 Elsevier B.V. -
Phishing attack detection using Machine Learning
Phishing is a type of digital assault, which adversely affects people where the client is coordinated to counterfeit sites and hoodwinked to screen their touchy and private data which integrates watchwords of records, monetary data, ATM pin-card data, etc. Recently safeguarding touchy records, it's fragile to cover yourself from malware or web phishing. AI is an investigation of information examination and logical investigation of calculations has demonstrated outcomes. Contradicting phishing sprinters with remarkable perception and felonious outcomes comparable as care shops, and custom against phishing approaches. This paper examines the association of Machine Literacy routes in identifying phishing assaults and records their advantages and drawbacks. There are countless Machine Learning calculations that have been dug to proclaim the relevant decision that act as against phishing apparatuses. We made a phishing section framework that extracts capacities that are expected to descry phishing. We likewise utilize numeric outline, as well as an overall investigation of customary Machine Learning methodologies comparable as Decision Tree, Random Forest, Multi-layer Perceptron's, XG Boost Classifier, SVM, Light BGM Classifier, Cat Boost Classifier, and covering grounded highlights choice, which contains the metadata of URLs and assists with deciding if a site is licit or not. 2022 The Authors -
A Smartphone Coupled Freshness Indicator Prepared by Rub-coating of Hibiscus Flowers on Paper substrates for Visual Monitoring of the Spoilage of Milk
This study developed an inexpensive and easy-to-use milk freshness indicator (H-Paper) by rub-coating hibiscus flowers onto paper. As per the best of our knowledge, this is the first example of a food quality indicator prepared by direct hand-rubbing of a natural halochromic material onto paper substrates. Unlike the previously reported colorimetric indicators from natural sources, our indicator does not require the extraction of anthocyanins from the natural product. The H-Paper undergoes a quantifiable color change from green to purple to pink corresponding to fresh, spoiling, and spoiled milk samples. Digital photographs of H-Paper treated with milk samples were acquired using a smartphone, and RGB indices were analyzed using a free application. The red chromatic shift was used as a parameter to quantify color change of H-Paper to follow the spoilage of milk. Anthocyanins present in the hibiscus flowers are responsible for this colorimetric response. This work demonstrates a proof-of-concept for directly rub-coating halochromic materials onto a substrate to fabricate food freshness indicators. The H-Paper indicator has advantages of naked-eye analysis, consumer-friendliness, and instrument-free operation. This requires neither any laboratory accessories nor the expertise of a trained analyst for its preparation and operation, which is appropriate for use in resource-limited settings. 2022 Wiley-VCH GmbH. -
Surface tempering of poly-(3 thiophene acetic acid) coated carbon fiber paper electrode with spine-like cobalt inorganic phosphate: An efficacious electrochemical metol sensor
N-methyl-p-aminophenol sulfate (metol) is a photographic developing agent that has a toxic effect on humans and aquatic life. A cost-effective and sensitive electrochemical sensor was developed by electrodepositing Co-Pi over poly-(3 thiophene acetic acid) coated carbon fiber paper electrode (Co-Pi/PTAA/CFP) for the determination of metol (ML). Surface modification of Co-Pi facilitates superior electrocatalytic performance by offering more active sites and faster electron transport kinetics. The Physico-chemical characterization of the fabricated electrode was carried out by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) Field emission scanning electron microscopy (FESEM) with energy-dispersive X-ray spectroscopy (EDS), Optical profilometer, Fourier transform infrared spectroscopy (FTIR), and electroanalytical techniques. The electrochemical studies were performed using Cyclic voltammetry (CV), Electron Impedance spectroscopy (EIS), and Differential pulse voltammetric (DPV). DPV studies revealed excellent sensing performance for ML, with a wide linear dynamic range of 6 nM to 800 nM, and a limit of detection (LOD) of 2 nM. A distinctive oxidative anodic peak was observed at 0.11 V indicating the excellent electrochemical performance of the electrode. The results suggested that the developed electrode exhibited good catalytic activity, selectivity, and sensitivity towards the electrochemical determination of ML. Further, the developed electrode was extended to its application in real samples obtained from lake water and domestic wastewater. 2022 -
Decision making framework for foreign direct investment: Analytic hierarchy process and weighted aggregated sum product assessment integrated approach
Foreign direct investment (FDI) plays a paramount role in economic and social growth of every country. FDI acts as a source of external capital and helps in economic growth of the host country. Making decision for FDI during uncertain business environment is a challenge for all stakeholders. Therefore, in this study, we are proposing a decision making framework for FDI. Through literature review, we have identified the factors, on which FDI depends. A process-based, multi-criterion, integrated hierarchical approach for deciding about FDI, has been illustrated. In this study, five sectors are considered, that is, petroleum and natural resource, retailing and e-commerce, healthcare, information technology, and road and highways for illustrating the proposed framework. It is observed that information technology sector has got top priority for FDI followed by retailing and e-commerce and health care sector. Findings will help in taking appropriate decision by stakeholders for FDI. Ultimately it will also help in creating employment, economic growth, and welfare of society at large in the host country. 2021 John Wiley & Sons, Ltd. -
Electro-osmotic effect on the three-layer flow of Binary nanoliquid between two concentric cylinders
The three-layer flow of an immiscible nanoliquid in composite annulus with an electro-kinetic effect is analyzed using Buongiornos model. This model helps in analyzing the impact of two major phenomena, namely thermophoresis and Brownian motion. In this model, an interfacial layer is formed between the liquids due to the immiscibility of the base liquids. The use of a multilayer model especially in cooling systems brings more applications in many industries such as nuclear, biomedical, and solar. Different from the earlier studies on multilayer channel flow, this paper explains the three-layer flow between two concentric cylinders in the presence of cross-diffusion which makes the work unique. Further, the middle region is assumed to be porous and heat source or sink is applied to the entire system. Also, the flux conservation condition for nanoparticle volume fraction is considered. The equations governing the problem are simplified and are solved using the differential transform method. The results indicate that the electroosmotic parameter enhances the velocity but reduces the electrostatic potential. Further, the diffusion ratio improves the temperature and decreases the solute concentration of the fluid. 2022, Akadiai Kiad Budapest, Hungary. -
An efficient technique for generalized conformablePochhammerChree models of longitudinal wave propagation of elastic rod
In this article, we introduce analytical-approximate solutions of time-fractional generalized Pochhammer-Chree equations for wave propagation of elastic rod by means of the q-homotopy analysis of the transform method (q-HATM). In the Caputo sense, basic concepts for fractional derivatives are defined. Several examples are given and the results are illustrated via some surface plots to present the physical representation. The results show that the current methodology is productive, powerful, efficient, easy to use, and ready to incorporate a wide variety of partial fractional differential equations. 2022, Indian Association for the Cultivation of Science. -
Non-Recombinant Mutagenesis of Bacillus mojavensis CUIE1819 for Hyper Production of Lipase and Treatment of Polluted Lakes
Microorganisms that degrade oil contribute significantly to the bioremediation of polluted lakes. Many microorganisms synthesize lipases, which are commercially significant. In the present study microorganisms producing extracellular lipase were isolated from various polluted lakes in Bangalore by using tributyrin agar. A lipase assay was done to determine the most efficient lipase-producing organism, which was then named Bacillus mojavensis CUIE1819 based on 16srRNA sequencing. After UV irradiation, the selected immobilized organisms were used to treat the lake water samples. 2022, Association of Biotechnology and Pharmacy. All rights reserved. -
Evaluation of Wound Healing Effect of Curcumin Loaded OPL Carbon Nanospheres Embedded Chitosan Membranes
Biowaste-derived carbon biomaterial scaffolds are being used for wound healing and are the focus of interest. Carbon nanospheres derived from oil palm leaves without any catalysts via pyrolysis were loaded with a traditional drug curcumin. The wound healing scaffolds were fabricated on the PP non-woven fabric support using chitosan as the biopolymer matrix. Prepared carbon nanospheres and the scaffolds were characterized using ATR-IR and FESEM techniques. The wettability of scaffolds was examined to ensure the feasible moisture absorption ability, in vitro drug release profile and in vitro antibacterial activity against two strains of bacteria. The in vivo wound healing feature of scaffolds was studied by excision wound model for MRSA infected wound. Measured wound contraction percentage and the bacterial count on wounds at regular time intervals proved that, the scaffold dressed with chitosan and curcumin loaded carbon nanospheres showed an efficient reconstruction of skin through histopathological investigations. 2022, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature. -
Radio pulsar sub-populations (II): The mysterious RRATs
Several conjectures have been put forward to explain rotating radio transients (RRATs), the newest subclass of neutron stars, and their connections to other radio pulsars. This work discusses these conjectures in the context of the characteristic properties of the RRAT population. Contrary to expectations, it is seen that: (a) the RRAT population is statistically un-correlated with the nulling pulsars and (b) the RRAT phenomenon is unlikely to be related to old age or death-line proximity. It is perhaps more likely that the special emission property of RRATs is a signature of them being later evolutionary phases of other types of neutron stars which may have resulted in restructuring their magnetic fields. 2022, Indian Academy of Sciences. -
Structural and functional characterization of a hypothetical protein in the RD7 region in clinical isolates of Mycobacterium tuberculosis an in silico approach to candidate vaccines
Background: Mycobacterium tuberculosis has been ravaging humans by inflicting respiratory tuberculosis since centuries. Bacillus Calmette Guerine (BCG) is the only vaccine available for tuberculosis, and it is known to be poorly effective against adult tuberculosis. Proteins belonging to the ESAT-6 family and PE/PPE family show immune responses and are included in different vaccine trials. Herein, we study the functional and structural characterization of a 248 amino acid long putative protein novel hypothetical protein 1 (NHP1) present in the RD7 region of Mycobacterium tuberculosis (identified first by subtractive hybridization in the clinical isolate RGTB123) using bioinformatics tools. Results: Physicochemical properties were studied using Expasy ProtParam and SMS software. We predicted different B-cell and T-cell epitopes by using the immune epitope database (IEDB) and also tested antigenicity, immunogenicity, and allergenicity. Secondary structure of the protein predicted 30% alpha helices, 20% beta strands, and 48% random coils. Tertiary structure of the protein was predicted using the Robetta server using the Mycobacterium smegmatis protein as the putative protein with homology. Structural evaluations were done with Ramachandran plot analysis, ProSA-web, and VERIFY3D, and with GalaxyWEB server, a more stable structure was validated with good stereo chemical properties. Conclusion: The present study of a subtracted genomic locus using various bioinformatics tools indicated good immunological properties of the putative mycobacterial protein, NHP1. Evidence obtained from the analyses of NHP1 using structure prediction tools strongly point to the fact that NHP1 is an ancient protein having flavodoxin folding structure with ATP binding sites. Positive scores were obtained for antigenicity, immunogenicity, and virulence too, implying the possibility of NHP1 to be a potential vaccine candidate. Such computational studies might give clues for developing newer vaccines for tuberculosis, which is the need of the hour. 2022, The Author(s). -
Long-term Optical and ?-Ray Variability of the Blazar PKS 1222+216
The ?-ray emission from flat-spectrum radio quasars (FSRQs) is thought to be dominated by the inverse Compton scattering of the external sources of photon fields, e.g., accretion disk, broad-line region (BLR), and torus. FSRQs show strong optical emission lines and hence can be a useful probe of the variability in BLR output, which is the reprocessed disk emission. We study the connection between the optical continuum, H? line, and ?-ray emissions from the FSRQ PKS 1222+216, using long-term (?2011-2018) optical spectroscopic data from Steward Observatory and ?-ray observations from Fermi Large Area Telescope (LAT). We measured the continuum (F C,opt) and H? (F H? ) fluxes by performing a systematic analysis of the 6029-6452 optical spectra. We observed stronger variability in F C,opt than F H? , an inverse correlation between the H? equivalent width and F C,opt, and a redder-when-brighter trend. Using discrete cross-correlation analysis, we found a positive correlation (DCF ? 0.5) between the F ??ray>100 MeV and F C,opt (6024-6092 light curves with a time lag consistent with zero at the 2? level. We found no correlation between the F ??ray>100 MeV and F H? light curves, probably dismissing the disk contribution to the optical and ?-ray variability. The observed strong variability in the Fermi-LAT flux and F ??ray>100 MeV ? F C,opt correlation could be due to the changes in the particle acceleration at various epochs. We derived the optical-to-?-ray spectral energy distributions during the ?-ray flaring and quiescent epochs that show a dominant disk component with no variability. Our study suggests that the ?-ray emission zone is likely located at the edge of the BLR or in the radiation field of the torus. 2022. The Author(s). Published by the American Astronomical Society. -
A note on ?(k)-colouring of the Cartesian product of some graphs
The chromatic number, x(G) of a graph G is the minimum number of colours used in a proper colouring of G. In an improper colouring, an edge uv is bad if the colours assigned to the end vertices of the edge is the same. Now, if the available colours are less than that of the chromatic number of graph G, then colouring the graph with the available colours lead to bad edges in G. The number of bad edges resulting from a ? (k)-colouring of G is denoted by bk(G). In this paper, we use the concept of (k)-colouring and determine the number of bad edges in Cartesian product of some graphs. 2022 by the authors. -
Laccase mediated electrosynthesis of heliotropin on mango-kernel derived carbon nanosphere composite: A sustainable approach
Facile fabrication of enzyme immobilized carbon nanospheres (CNS) based catalysts with high electrical conductivity and catalytic efficiency are of decisive importance for their electrocatalysis. A novel, green and highly efficient synthesis route for the development of an electrode surface with enhanced electrical conductivity and better catalytic activity for the electrochemical synthesis of heliotropin. The obtained biowaste (mango seed kernels) was pyrolyzed and subjected to acid treatment to form functionalized CNS (f-CNS). The functionalized carbon fiber paper (CFP) electrode was employed as a template for laccase immobilization which was further treated with free laccase resulting in the formation of Lac-fCNS/CFP electrode. The developed electrode exhibited excellent electrooxidation of piperonyl alcohol in the presence of 2,2,6,6-Tetramethyl-1-piperidinyloxy (TEMPO), which served as the mediator. A high yield (78%) of heliotropin was achieved during the electrooxidation at 0.78 V via bulk electrolysis. The obtained product (heliotropin aka piperonal) was confirmed via 1H NMR and 13C NMR. Additionally, computational molecular docking analysis of f-CNS:laccase composite showed strong binding affinity (?6.2 kcal/mol) with TEMPO in comparison with free laccase (?5.1 kcal/mol). The excellent selectivity and efficiency of the developed electrocatalyst aim to surpass all other reported laccase-TEMPO mediated based electrocatalytic oxidation reactions. 2022 Vietnam National University, Hanoi -
Analysis and optimization of uplink spectral efficiency in massive multiple-input and multiple-output
Fifth Generation (5G) specifications aims for data rate of 1 Gbps in high mobility and 10 Gbps in low mobility conditions, 15-30 bps/Hz of spectral efficiency with less than 1 milli second (ms) latency reduction. Massive multiple-input and multiple-output (Massive MIMO) is one of the promising technologies in 5G standard which offers a high spectral efficiency improvement. This work focus on the uplink scenario spectral efficiency in a Massive MIMO simulation network based on third generation partnership project (3GPP) and long term evolution (LTE) document of 5G. This work analyzes the spectral efficiency metric by simulating the 5G Massive MIMO network. Then, the research identified major constraint parameters; number of user antennas, K, number of base station antennas, M, transmission power, P, channel bandwidth, B, and coherence time, Tau_C and pilot time Tau_P which plays a significant role in varying this metric. The authors focus on improving the spectral efficiency by passing these constraint parameters through different meta-heurestic optimization algorithms, such as, convex optimization solver, White shark optimization (WSO) and Particle swarm optimization (PSO). The results show an overall, 1-10 percent of improvement of the parameter wnen compared with other research articles. The maximum value achieved is 49.84 bps/Hz, which is three times higher as per to the 3GPP and International Telecommunication Unioin (ITU) release document. 2022 Institute of Advanced Engineering and Science. All rights reserved. -
Study of X-Ray Intraday Variability of HBL Blazars Based on Observations Obtained with XMM-Newton
We present an extensive study on the X-ray intraday variability of 10 teraelectronvolt-emitting high synchrotron peaked blazars (HBLs): 1ES 0229+200, 1ES 0414+009, PKS 0548-322, 1ES 1101-232, 1H 1219+301, H 1426+428, Mrk 501, 1ES 1959+650, PKS 2005-489, and 1ES 2344+514 made with 25 XMM-Newton pointed observations during its operational period. Intraday variability has been estimated in three energy bands: soft (0.3-2 keV), hard (2-10 keV), and total (0.3-10 keV). Although seven out of 10 teraelectronvolt HBLs exhibited some intraday variability at 3? levels, no major variations exceeding 6% were detected. We explored the spectral properties of the sample by extracting the hardness ratio from the soft and hard bands; no significant variations in the hardness ratio were observed in any source. We performed power spectral density analyses on the variable light curves by fitting power laws, yielding slopes lying in the range of 1.11-2.93 for different HBLs. We briefly discuss possible emission mechanisms and carry out rough estimates for magnetic fields, electron Lorentz factors, and emission region sizes for seven of these HBLs. 2022. The Author(s). Published by the American Astronomical Society. -
Color image segmentation based on improved sine cosine optimization algorithm
Segmentation refers to the process of dividing an image into multiple regions based on some criteria such as intensity and color. In recent years, color image segmentation has received considerable attention from the researchers. However, it is still a highly complicated task due to the presence of more attributes or components as compared to monochrome images. Numerous meta-heuristics algorithms are developed to determine the optimal threshold value for segmenting color images efficiently. This paper presents an enhanced sine cosine algorithm (ESCA) to seek threshold for segmenting color images. Sine cosine algorithm (SCA) is a population-based optimization algorithm which has the ability of preventing local minima problem. First an input image is transformed to CIE L*a*b* color reduced space. ESCA is applied to determine the optimal threshold values for segmentation. The performance of the proposed method is tested on color images from Berkeley database, and segmentation results are compared with two metaheuristic algorithms, namely particle swarm optimization (PSO) and standard SCA. Experimental results are validated by measuring peak signalnoise ratio (PSNR), structural similarity index and computation time for all the images investigated. Results revealed that the proposed method outperforms the other methods like PSO and SCA by achieving PSNR of 23dB and SSIM of 0.93 and also require less time for finding optimal threshold values than PSO and SCA. 2022, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.