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Stable copper nanoparticles as potential antibacterial agent against aquaculture pathogens and human fibroblast cell viability
The developments of green nanotechnology are generating interest of researchers towards synthesis of copper nanoparticles due to their increasing application towards the biomedical field. The utilization of phytochemicals in plant extracts have become a valuable trend in the synthesis of nanoparticles as they possess dual nature of reducing and stabilizing agents. In this work a simple and rapid biosynthesis route for producing stable fenugreek copper nanoparticles (FCuNPs) using Trigonella foenum-graecum is demonstrated and assessed its antibacterial activity against gram negative Vibrio species. The characterization of synthesized FCuNPs was carried out using UVvis spectrophotometer and the SPR of FCuNPs is observed at 350 nm. TEM, HRTEM SAED analysis was done to evaluate the morphology and size of FCuNPs. FTIR spectra of both the plant extract and FCuNPs were recorded in order to study the interaction of phytochemicals with FCuNPs. The antibacterial activity of biosynthesized FCuNPs was tested against V. vulnificus, V. harveyi and V. parahaemolyticus using agar well diffusion technique. Since this method of synthesizing copper nanoparticles does not involve any harmful chemicals, the FCuNPs produced are more biocompatible and were used to evaluate human skin fibroblast cell line by Alamar Blue reduction assay. The outcomes of this report will surely provide a new path in the field of nanotechnology and nano medicine where there is a significant need of antibacterial and cell viability studies. Hence, FCuNPs can be powerful therapeutic materials in numerous biomedical applications, which are to be discovered in the near prospective. 2021 Elsevier Ltd -
Second Order Parallel Tensor on Almost Kenmotsu Manifolds
Let M be an almost Kenmotsu manifold of dimension 2n + 1 having nonvanishing ?-sectional curvature such that tr? > -2n -2. We prove that any second order parallel tensor on M is a constant multiple of the associated metric tensor and obtained some consequences of this. Vector fields keeping curvature tensor invariant are characterized on M. Kyungpook Mathematical Journal -
Impact of Lysinibacillus macroides, a potential plant growth promoting rhizobacteria on growth, yield and nutritional value of tomato plant (Solanum lycopersicum L. F1 hybrid Sachriya)
Plant growth promoting bacteria enhance the growth in plants by solubilizing insoluble minerals, producing phytohormones and by secreting enzymes that resist pathogen attack. The present study was aimed at identifying the potential of Lysinibacillus macroides isolated from pea plant possessing rich microbial rhizobiome diversity in promoting the growth of tomato plant (Solanum lycopersicum L.). Potential of L. macroides in the promotion of S. lycopersicum L. growth by increased shoot length, terminal leaf length and breadth was assessed. Anatomical sectioning of stem and root revealed no varied cellular pattern indicating that the supplemented bioculture is not toxic to S. lycopersicum. Plantlets treated with L. macroides along with organic compost showed an increased total phenol content (17.580.4 mg/gm) compared to control samples (12.440.41 mg/g). Carbohydrate content was noticed to be around 1.3 folds higher in the L. macroides plus compost mixture supplemented slots compared to control sample. Significant increase in shoot length was evident in the L. macroides plus compost supplied slots (23.42.7 cm). Plant growth promoting properties might be due to the nitrogen fixing activity of the bacteria which enrich the soil composition along with the nutrients supplied by the organic compost. Rich microbial rhizobiome diversity in pea plant and the usage of L. macroides from a non-conventional source improves the diversity of the available PGPR for agricultural practices. Further research is needed to detect the mechanism of growth promotion and to explore the plant microbe interaction pathway. Jyolsna et al. (2021). -
Portrait segmentation using ensemble of heterogeneous deep-learning models
Image segmentation plays a central role in a broad range of applications, such as medical image analysis, autonomous vehicles, video surveillance and augmented reality. Portrait segmenta-tion, which is a subset of semantic image segmentation, is widely used as a preprocessing step in multiple applications such as security systems, entertainment applications, video conferences, etc. A substantial amount of deep learning-based portrait segmentation approaches have been developed, since the performance and accuracy of semantic image segmentation have improved significantly due to the recent introduction of deep learning technology. However, these approaches are limited to a single portrait segmentation model. In this paper, we propose a novel approach using an ensemble method by combining multiple heterogeneous deep-learning based portrait segmentation models to improve the segmentation performance. The Two-Models ensemble and Three-Models ensemble, using a simple soft voting method and weighted soft voting method, were experimented. Intersection over Union (IoU) metric, IoU standard deviation and false prediction rate were used to evaluate the performance. Cost efficiency was calculated to analyze the efficiency of segmentation. The experiment results show that the proposed ensemble approach can perform with higher accuracy and lower errors than single deep-learning-based portrait segmentation models. The results also show that the ensemble of deep-learning models typically increases the use of memory and computing power, although it also shows that the ensemble of deep-learning models can perform more efficiently than a single model with higher accuracy using less memory and less computing power. 2021 by the authors. Licensee MDPI, Basel, Switzerland. -
Structural domination and coloring of some (P7,C7)-free graphs
We show that every connected induced subgraph of a graph G is dominated by an induced connected split graph if and only if G is C-free, where C is a set of six graphs which includes P7 and C7, and each containing an induced P5. A similar characterization is shown for the class of graphs which are dominated by an induced connected complete split graph. Motivated by these results, we study structural descriptions of some classes of (P7, C7)-free graphs. In particular, we give structural descriptions for the class of (P7, C7, C4, gem)-free graphs and for the class of (P7, C7, C4, diamond)-free graphs. Using these results, we show that every (P7, C7, C4, gem)-free graph G satisfies ?(G)?2?(G)?1, and that every (P7, C7, C4, diamond)-free graph H satisfies ?(H)?max{3,?(H)}. 2020 Elsevier B.V. -
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. -
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. -
An efficient approach for fractional nonlinear chaotic model with Mittag-Leffler law
In this work, we exemplify the behaviour of the nonlinear model of arbitrary order differential equations by adopting q-homotopy analysis transform method (q-HATM). In the present study, the illustrated scheme is a graceful amalgamation of Laplace transform with q-homotopy analysis algorithm and we considered arbitrary order derivative using Atangana-Baleanu (AB) operator. The suggested nonlinear system exhibits chaotic behaviour in nature with respect to considered initial conditions. Fixed point hypothesis heard present the existence and uniqueness for the attained solution. We exemplified suggested arbitrary order system with to illustrate and confirm the efficiency of the projected solution procedure. Further, the numerical simulation is illustrated and also the chaotic behaviour of the obtained result captured with respect to arbitrary order in terms of plots. The obtained results confirm the projected scheme is highly methodical, easy to implement and very powerful to exemplify the nature of the dynamical system of arbitrary order. 2021 The Author(s) -
Thermal and entropy generation of non-Newtonian magneto-Carreau fluid flow in microchannel
The heat flow in microchannels can be established in numerous applications such as micro air vehicles, mechanicalelectromechanical systems, cooling of electronic devices and micro heat exchanger systems. Heat flow optimization deliberates the function of entropy generation minimization (EGM) in engineering applications. Hence, this paper investigates the heat transport of non-Newtonian magneto-Carreau fluid in a microchannel with EGM. Mathematical modeling incorporates the Carreau fluid model. Further, viscous heating, Joule heating and convective heating aspects are also analyzed. The physical features of entropy production in the flow of non-Newtonian Carreau fluid in a microchannel are the major focus of this model. Dimensionless variables are executed for the simplicity of basic equations. The subsequent system is treated by using finite element method. Behaviors of effective parameters on velocity, Bejan number, entropy generation rate and temperature are interpreted. It is established that EGM is occurred for larger values of Weissenberg number. The Carreau fluid exponent is positively related to Bejan number, whereas it is negatively related to EG, temperature and velocity fields. 2020, Akadiai Kiad Budapest, Hungary. -
Segregating direct and indirect dimensions in ecosystem services valuation: The case of a coastal wetland ecosystem of south india
This paper provides insights into the multiple (direct and indirect) benefits of Kuttanad coastal wetland ecosystem in Kerala. Total annual direct ecosystem services generated from the wetlands are INR 8.45 billion or USD 0.11 billion per annum at 2020 prices. The estimates of the case study indicate that the annual value of indirect ecosystem services is thrice of direct provisioning services (Rs 22.52 billion or USD 0.31 billion per annum at 2020 prices). The valuation study would improve the knowledge and awareness of economic importance of wetland ecosystems among the various stakeholders including the policy makers of the society and their sustainable management to benefit the society. 2021 Ecological Society of India. All rights reserved. -
Dust reverberation mapping of Z229-15
We report results of the dust reverberation mapping (DRM) on the Seyfert 1 galaxy Z229-15 at z = 0.0273. Quasi-simultaneous photometric observations for a total of 48 epochs were acquired during the period 2017 July to 2018 December in B, V, J, H and Ks bands. The calculated spectral index (?) between B and V bands for each epoch was used to correct for the accretion disc (AD) component present in the infrared light curves. The observed ? ranges between -0.99 and 1.03. Using cross-correlation function analysis we found significant time delays between the optical V and the AD corrected J, H and Ks light curves. The lags in the rest frame of the source are 12.52+10.00 -9.55 d (between V and J), 15.63+5.05 -5.11 d (between V and H) and 20.36+5.82 -5.68 d (between V and Ks). Given the large error bars, these lags are consistent with each other. However, considering the lag between V and Ks bands to represent the inner edge of the dust torus, the torus in Z229-15 lies at a distance of 0.017 pc from the central ionizing continuum. This is smaller than that expected from the radius luminosity (R-L) relationship known from DRM. Using a constant ? = 0.1 to account for theADcomponent, as is normally done in DRM, the deduced radius (0.025 pc) lies close to the expected R-L relation. However, usage of constant ? in DRM is disfavoured as the ? of the ionizing continuum changes with the flux of the source. 2021 Oxford University Press. All rights reserved. -
Down syndrome detection using modified ant colony optimization algorithm
Nowadays, the systems related to healthcare are restructured with innovative skills to offer humans more intellectual and proficient healthcare facilities. Various intelligent healthcare systems are exhibited with the help of machine learning and artificial intelligent tools to offer intellectual and expert services. In human body genetic codes are stored in the genes. All of our inherited traits are associated with these genes and are grouped as structures generally called chromosomes. In typical cases, each cell consists of 23 pairs of chromosomes, out of which each parent contributes half. But if a person has a partial or full copy of chromosome 21, the situation is called Down syndrome. It results in intellectual disability, reading impairment, developmental delay, and other medical abnormalities. This paper introduces an intelligent prediction and classification system for healthcare, feature selection based on density with Ant Colony Optimization (ACO) algorithm for Down syndrome (DS). 2021, Engg Journals Publications. All rights reserved. -
Predicting of Open Source Software Component Reusability Level Using Object-Oriented Metrics by Taguchi Approach
Component-based software development (CBSD) is an efficient approach used by software developers to develop new software. The commercial off the shelf (COTS) and open-source software (OSS) are two styles to implement CBSD. The COTS provides the interface and depicts the black-box behavior, but does not support several software quality characteristics. On the other hard, OSS is a more efficient approach compared to COTS due to its source code availability. This research aims to identify the reusability level of OSS components from an online repository of OSS. The OSS components are classified based on Chidamber and Kemerer reusability metrics (CK-metrics). This paper proposed a mathematical model to establish the relationship between the reusability of CK-metrics. Reusability level of OSS component has been measured and most effective CK-metrics obtained by applying the Taguchi design and analysis of variance (ANOVA). The input parameters for the experimental design are evaluated based on the OSS repository. Performance analysis has been carried out based upon the interaction effect between the reusability of CK-metrics. Main effect plots are created to identify the most reusable component of the OSS. The genetic algorithm (GA) is used to predict the optimized value of the different control parameters. The results indicate that the OSS component reusability level is 0.698194. The reusability of software has a significant effect on the quality of software. The quality of software can be improved by increasing the reusability of software components. 2021 World Scientific Publishing Company. -
A study of the natural convection of water- AA 7075 nanoliquids in low-porosity cylindrical annuli using a local thermal non-equilibrium model
Natural convection in nanoliquid-saturated porous cylindrical annuli due to uniform heat and mass influxes from the solid cylinder and effluxes from the outer hollow cylinder is investigated analytically. The Darcy model and the modified version of the Buongiorno two-phase model are used, and local thermal non-equilibrium between the phases is assumed. A nanoliquid-saturated porous medium made up of glass balls with a dilute concentration of AA7075 alloy nanoparticles well-dispersed in water is considered. Out of three types of annuli considered, shallow annuli provide the best heat transport and tall annuli show the worst performance. The presence of a dilute concentration of nanoparticles significantly enhances the heat transport in the system. Of nine nanoparticle shapes considered, lamina-shaped nanoparticles enhance heat transport the most. Heat transport is enhanced in the case of heat-and-mass-driven convection compared to the case of purely heat-driven convection. The results for a rectangular enclosure are obtained as a particular case of the present study. Two asymptotic routes that take us to the results of thermal equilibrium are shown. The vanishing limit of the concentration Rayleigh number yields the result for a single-phase model. Results for the base-liquid-saturated porous medium form a limiting case of the present study. We conclude that a shallow cylindrical annulus saturated with water-AA7075 lamina-shaped alloy nanoparticles is best suited for heat transfer due to its high effective thermal conductivity in comparison with that of other shaped nanoparticles and a tall rectangular enclosure saturated by water is best suited for heat storage applications. 2021 Author(s). -
An aqueous phase TEMPO mediated electrooxidation of 2-thiophenemethanol using MnO2-Pi dispersed nanocarbon spheres on a carbon fiber paper electrode
An environmentally benign and economic method was developed for the electrocatalytic oxidation of 2-thiophenemethanol in an aqueous acidic medium. Nanocarbon spheres (NCS) coated on carbon fiber paper (CFP) were used as a host matrix to disperse manganese dioxide nanoparticles from phosphate buffer solution through electrochemical deposition. The developed electrode (MnO2-Pi-NCS/CFP) was used as a working electrode for electrochemical oxidation of 2-thiophenemethanol in the presence of a mediator TEMPO in 0.01 M H2SO4 medium. Different analytical methods were used to characterize the modified electrodes. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used to study the electrochemical properties of the modified electrodes. The electrochemically active surface area values calculated for bare CFP, NCS coated CFP and MnO2-Pi-NCS/CFP electrodes were found to be 1.43 cm2, 2.86 cm2, and 6.72 cm2 respectively for the geometric area of 0.7 cm2 of the electrodes. Coating of NCS and MnO2-Pi resulted in porosity and roughness of the CFP electrode which enhances the surface area. MnO2-Pi-NCS/CFP demonstrated higher electrocatalytic activity for oxidation of 2-thiophenemethanol to 2-thiophenemethanal in aqueous acidic media with a TEMPO mediator compared to unmodified electrodes. This journal is 2021 The Royal Society of Chemistry. -
Antenna Array with Non-Uniform Excitation and DNG Hybrid Metasurface for Next Generation Communication Equipment
This paper presents an approach for designing a hybrid metasurface array with nonuniform excitation. The proposed design features a unique feed network with minimal use of Quarter Wave Transformers (QWT's) to reduce the form-factor. The impedance matching between the feed network and the patch is achieved by adjusting the inset position and the gap between the patch and the feed. The metasurface consists of a hybrid metamaterial unit cell with five Split Ring Resonators (SRRs) on the bottom and a hexagonal ring made of six triangles on the top surface improves the bandwidth, gain and directivity of the proposed design. Equivalent circuit of the proposed array is modeled using ADS software. A prototype 1x4 array with metasurface is designed for a resonant frequency of 2.4 GHz and fabricated. A high gain of 9.46 dB with a -10 dB impedance bandwidth of 110 MHz is achieved, which amounts to an improvement of 16.36% gain and 31.58% bandwidth compared to conventional uniform excitation array. In terms of overall size, the proposed array antenna is reduced by 38.05% compared to traditional 1x4 microstrip array. 2021 IAMOT. All Rights Reserved. -
Analysis of the chemical properties and high-temperature rheological properties of MDI modified bio-asphalt
As an environmentally friendly material, bio-oil is employed to partially replace non-renewable petroleum asphalt, but its addition weakens the high-temperature non-deformability of petroleum asphalt. Therefore, the 4,4?-diphenylmethane diisocyanate (MDI) was employed as a chemical modifier of bio-asphalt to improve its high temperature rheological properties. The MDI with addition of 0.5%, 1%, 2%, 4% by weight, and the bio-oil with addition of 12% were used to obtain the MDI modified bio-asphalts. The chemical reaction mechanism between the MDI and bio-asphalt was analyzed by employing the Fourier-transform infrared spectroscopy (FTIR) and gel permeation chromatography (GPC) tests. Meanwhile, the rotational plate viscosity (RPV) test, the temperature sweep test, and the multiple stress creep and recovery (MSCR) test were employed to evaluate the high-temperature rheological properties of the MDI modified bio-asphalts. Moreover, the relationships between the chemical reaction mechanism and high-temperature rheological parameters of MDI modified bio-asphalt were established. Test results show that a nucleophilic addition reaction occurred between the MDI and the active hydrogen of bio-asphalt to form urethane chains, which increased the content of macromolecular polymers in the bio-asphalt. The MDI increased the G*/sin? (rutting factor) and the E(?) (visco-flow activation energy) of the bio-asphalt, but decreased its permanent strain and Jnr (non-recoverable creep compliance). Therefore, the MDI modifier effectively enhanced the permanent non-deformability of the bio-asphalt. Both IUrethane and LMS were positively correlated with the rutting factor, viscosity and 1/Jnr, and had significant correlations at a significance level of 0.05. Furthermore, the optimal ratio of MDI to bio-oil was determined to be 1:6 by mass. 2020 Elsevier Ltd -
Hybrid AODV: An Efficient Routing Protocol for Manet Using MFR and Firefly Optimization Technique
A MANET is a category of ad hoc protocol that could vary positions and track itself on the flutter. It utilizes wireless connections that are attached to several networks. They include wirelessly in a self-configured, self-healing network while not having permanent communication linked in a collection of mobile networks. The network topology of nodes typically varies in MANET, and nodes are free to stir errantly and independently as a router as they accelerate traffic to more nodes within the network. Ad hoc on-demand distance vector (AODV) was employed for node selection to attain the shortest path strategy in existing techniques. In the proposed system, the hybrid AODV (HAODV) technique incorporates the MFR (Most Forward within Radius) technique to detect the shortest path routing algorithm. The MFR method was deployed for selecting the neighbor node, while HAODV was deployed to find the shortest path. To find the shortest path based on the updating equation, the Firefly algorithm is also implemented into the Hybrid AODV. The proposed work's performance is calculated by different network parameters like the end to end delay, average routing overhead, throughput, and packet delivery ratio. After comparing AODV and DSR algorithms, the proposed algorithm (HAODV) shows improvement in packet delivery ratio, end-To-end delay, Routing overhead, and throughput. 2021 World Scientific Publishing Company. -
Electronic structure and intrinsic dielectric polarization of defect-engineered rutile TiO2
Experimental realization of colossal permittivity associated with intrinsic dielectric polarization of defect-engineered (Nb, In) co-doped rutile TiO2 appears to be most suitable for microelectronics and solid-state device applications. Combining resonant photoemission spectroscopy, X-ray absorption spectroscopy, and density functional theory calculations, we here present a coherent understanding of electronic structure, in-gap defect states, doped electron localization, and their connection with macroscopic polarization for various doping configurations. Most often, conventional sample preparation conditions introduce in-gap states of Ti3+? character, limiting the maximum achievable intrinsic polarization value. Our understanding provides a pathway to enhance intrinsic polarization and minimize dielectric loss through suitable defect-engineering. The Royal Society of Chemistry. -
Nanoparticle aggregation effects on radiative heat transport of nanoliquid over a vertical cylinder with sensitivity analysis
A sensitivity analysis is performed to analyze the effects of the nanoparticle (NP) aggregation and thermal radiation on heat transport of the nanoliquids (titania based on ethylene glycol) over a vertical cylinder. The optimization of heat transfer rate and friction factor is performed for NP volume fraction (1% ? ? ? 3%), radiation parameter (1 ? Rt ? 3), and mixed convection parameter (1.5 ? ? ? 2.5) via the face-centered central composite design (CCD) and the response surface methodology (RSM). The modified Krieger and Dougherty model (MKDM) for dynamic viscosity and the Bruggeman model (BM) for thermal conductivity are utilized to simulate nanoliquids with the NP aggregation aspect. The complicated nonlinear problem is treated numerically. It is found that the temperature of nanoliquid is enhanced due to the aggregation of NPs. The friction factor is more sensitive to the volume fraction of NPs than the thermal radiation and the mixed convection parameter. Furthermore, the heat transport rate is more sensitive to the effect of radiative heat compared with the NP volume fraction and mixed convection parameter. 2021, Shanghai University and Springer-Verlag GmbH Germany, part of Springer Nature.