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Ge-GaAs-Ge Heterojunction MOSFETs for Mixed-Signal Applications
A lattice matched heterojunction intraband tunnel (HJIBT) FET is proposed. The performance dependence of the device on conduction band (CB) discontinuity at source-channel and drain-channel interface is addressed using numerical simulation. Various mechanisms governing transport phenomena in the HJIBT FET are investigated in detail for different CB offsets (CBOs). For low gate to source voltage ( ${V}_{\text {GS}}$ ), thermionic emission is found to be the most significant transport mechanism. For moderate ${V}_{\text {GS}}$ , intraband tunneling phenomenon dominates over thermionic emission and continues to remain so. At high ${V}_{\text {GS}}$ , band-to-band tunneling occurs in HJIBT FETs. The proposed device shows improved figures of merit such as drain-induced barrier lowering (DIBL), ON-current ( ${I}_{ \mathrm{\scriptscriptstyle ON}}$ ) to OFF-current ( ${I}_{ \mathrm{\scriptscriptstyle OFF}}$ ) ratio ( ${I}_{ \mathrm{\scriptscriptstyle ON}}/{I}_{ \mathrm{\scriptscriptstyle OFF}}$ ), subthreshold slope (SS), gate capacitance ( ${C}_{\text {G}}$ ), ${g}_{m}$ (transconductance), and ${f}_{T}$ (cut-off frequency), with respect to conventional MOSFET. Also, the design of a high-performance hybrid 6T-static random access memory (SRAM) is proposed. 1963-2012 IEEE. -
Electrochemical sensing of vitamin B12 deficiency marker methylmalonic acid using PdAu-PPy tailored carbon fiber paper electrode
Vitamin B12 is very important for human metabolism and its deficiency can cause anemia and the production of large red blood cells. An increased concentration of methylmalonic acid (MMA) is detected much before the transformation of blood cells, which thereby is an early indicator for mild or serious Vitamin B12 deficiency. A simple electrochemical sensor based on PalladiumGold (PdAu) was developed by electrodeposition of PdAu nanoparticles on Polypyrrole (PPy) modified carbon fiber paper (CFP) electrode. The modified electrodes were characterized by High resolution transmission electron microscopy (HRTEM), Field emission scanning electron microscopy (FESEM) with energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and electroanalytical techniques. Differential Pulse Voltammetric (DPV) studies have established that under optimum conditions, the developed sensor exhibits a broad linear dynamic range (4.01 pM - 52.5 nM) with a very low detection limit (1.32 pM). The proposed method was effectively applied in the non-enzymatic determination of MMA at an ultralow level in human blood serum and urine samples. The method displayed high selectivity toward MMA in the presence of other interfering substances. 2020 Elsevier B.V. -
Synthesis, spectral and DNA/Protein binding evaluation of novel Cu(II) chelates of an NNO donor tridentate aroylhydrazone: Halogen bonding directed close packing
An NNO donor aroylhydrazone monohydrate, HFPBH2O (3-fluoropyridine-2-carbaldehyde benzoylhydrazone monohydrate) was synthesized from 3-fluoropyridine-2-carbaldehyde and benzhydrazide and physicochemically characterised. The coordination behaviour of the aroylhydrazone with the metal ion is investigated through various physicochemical techniques and it is concluded that it binds to the metal ion predominantly in the enolate resonance form, while few complexes exhibit keto form of the ligand. The structure of [Cu(FPB)(OAc)(H2O)]H2O (4a) established by single-crystal X-ray diffraction method unveiled that the metal ion has a distorted square-pyramidal geometry in this complex. The coordination sites of Cu(II) ion are occupied by azomethine N, pyridyl N and iminolate O from a monodeprotonated hydrazone moiety and the remaining two positions are occupied by two oxygen atoms, one each from acetate ion and the water molecule. Potential applications of the complexes were studied by subjecting them to DNA/protein (BSA) binding studies using electronic and fluorescence spectroscopy. The complexes were found to bind with DNA/protein (BSA) with binding constants in the order of 104 M?1 to 105 M?1. The intercalative mode of binding of the complexes with DNA was proved using spectral studies and molecular docking. Furthermore, the complex [Cu(FPB)(N3)(H2O)2] (5) was found to cleave the DNA from form I to form II during gel electrophoresis studies. 2020 Elsevier B.V. -
MnO2 Nanoclusters Decorated on GrapheneModified Pencil Graphite Electrode for Non-Enzymatic Determination of Cholesterol
Electrochemically deposited MnO2 on graphene coated Pencil Graphite Electrode (PGE) has been used to develop a facile electrochemical sensor for the determination of Cholesterol. Cyclic voltammetric (CV) studies and electrochemical impedance spectroscopic (EIS) technique were used to investigate the electrochemical properties of the modified sensing platform. The physicochemical properties of the modified electrodes were characterized by X-ray photoelectron spectroscopy (XPS), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The experimental conditions such as effect of scan rate, concentration and pH were optimized. The linear dynamic range for the determination of Cholesterol was found to be 120?10 M2400?10 M under optimum conditions. The ultralow level of detection limit (0.42 nM) demonstrates the high sensitivity of the proposed method. The developed method was successfully applied for the non-enzymatic determination of Cholesterol in human blood samples at ultralow levels. 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim -
Effect of gravity modulation on linear, weakly-nonlinear and local-nonlinear stability analyses of stationary double-diffusive convection in a dielectric liquid
The paper deals with the study of effect of gravity modulation on double-diffusive convection in a dielectric liquid for the cases of rigid-rigid and free-free boundaries. Using a modified Venezian approach, expressions for the Rayleigh number and its correction are determined. FourierGalerkin expansion is employed for a weakly nonlinear stability analysis and this results in a fifth-order Lorenz system that retains the structure of the classical one in the limiting case. A local nonlinear stability analysis using the method of multiscales leads to the time-periodic GinzburgLandau equation from the time-periodic generalized Lorenz system and the numerical solution of this simpler equation helps in quantifying unsteady heat and mass transports. Influence of various non-dimensional parameters (Lewis number, solutal Rayleigh number, electrical Rayleigh number and Prandtl number), amplitude and frequency of gravity modulation on onset of convection and heat and mass transports is discussed. The study reveals that the influence of gravity modulation is to stabilize the system and enhance heat and mass transports. The results from free-free boundaries are qualitatively similar to that of rigid-rigid boundaries. Further, it is shown that in the case of free-free boundaries the heat and mass transports are less compared to those of rigid-rigid boundaries. 2020, Springer Nature B.V. -
Spectroscopic and TDDFT investigation of highly selective fluoride sensors by substituted acyl hydrazones
In this work, we report the synthesis of two receptors for fluoride ions based on acyl hydrazone, such as N?-[(1Z)-1-(4-fluorophenyl)ethylidene]benzohydrazide (R1) and N?-[(1Z)-1-(2-hydroxyphenyl)ethylidene]benzohydrazide (R2). The receptors R1 and R2 were synthesized from the corresponding ketones and benzoic acid hydrazide and characterized spectroscopically by UVvisible, IR and 1HNMR techniques. The response of R1 and R2 towards different anions was studied colourimetrically in acetonitrile. The receptors exhibited a specific response towards fluoride ions. Further studies of 1:1 composition of receptors, R1/R2:fluoride ions by different spectroscopic techniques such as UVVisible, IR and 1HNMR spectroscopy indicated the participation of -NH proton of the receptors in the sensing action through the hydrogen bonding. To understand the mechanism, Time-Dependent Density Functional Theory (TD-DFT) studies were done using the CAM-B3LYP/6311G++ (3df,2p) with Grimme's D3BJ empirical dispersion basis set. The studies supported the role of hydrogen bonding interaction of -NH and-OH protons of the receptors with the fluoride ions. 2020 Elsevier B.V. -
Randomized response model to alter the nuisance effect of non-response due to stigmatized issues in survey sampling
The present study deals with the estimation procedures of the mean number of persons bearing a rare sensitive attribute in the clustered population under two-stage sampling scheme. The resultant estimators have been suggested using two-stage randomized response model when a rare unrelated attribute is assumed to be known as well as unknown. The properties of resultant estimators are studied where the first-stage samples are drawn using the probability proportional to the size with replacement sampling scheme. The estimation procedures have been further extended for the stratified clustered population. The empirical studies are performed for the validation of the suggested estimation procedures. Recommendations have been made to survey practitioners for their real-life applications. 2020 Informa UK Limited, trading as Taylor & Francis Group. -
Effect of heavy metals on the andrographolide content, phytochemicals and antioxidant activity of Andrographis paniculata
Andrographis paniculata is a medicinal plant that has several medicinal properties and has been traditionally used in different medicinal preparations. The present study deals with the influence of heavy metals (lead, mercury and silver) on andrographolide, phytochemicals and antioxidant activity in Andrographis paniculata. Two months old saplings were subjected to heavy metal stress of two different concentrations (0.2 mM and 0.4 mM) for three different times at 3 day time interval. The results showed that the saplings treated with heavy metals showed increased concentration of andrographolide content. The saplings treated with 0.4 mM silver showed the highest increase in the andrographolide content (24.58 2.85 mg/g of DW) compared with control (9.41 1.26 mg/g of DW) and other treatments. Variations in the biochemical parameters like total phenolic content, total flavonoid content, etc. were also prominent with all the treated samples when compared to that of control. 2020 Chemical Publishing Co.. All rights reserved. -
Logistic growth and SIR modelling of coronavirus disease (COVID-19) outbreak in India: Models based on real-time data
The logistic growth model and the Susceptible-Infectious-Recovered (SIR) framework are utilized for the mathematical modelling of the Coronavirus disease (COVID-19) outbreak in India. Karnataka, Kerala and Maharashtra, three states of India, are selected based on the pattern of the disease spread and the prominence in being affected in India. The parameters of the models are estimated by utilizing real-time data. The models predict the ending of the pandemic in these states and estimate the number of people that would be affected under the prevailing conditions. The models classify the pandemic into five stages based on the nature of the infection growth rate. According to the estimates of the models it can be concluded that Kerala is in a stable situation whereas the pandemic is still growing in Karnataka and Maharashtra. The infection rate of Karnataka and Kerala are lesser than 5% and reveal a downward trend. On the other hand, the infection rate and the high predicted number of infectives in Maharashtra calls for more preventive measures to be imposed in Maharashtra to control the disease spread. The results of this analysis provide valuable information regarding the disease spread in India. 2020, International Information and Engineering Technology Association. -
Effect of Ethnocentrism and Attitude Towards Foreign Brands in Purchase Decision
Ethnocentrism refers to the intense preference for domestic products or a moral obligation to buy domestic products. With an extraordinary amount and variety of foreign goods and services now being made available to the Indian market, the level of competition faced by domestic companies has tremendously increased. This forms the need for domestic marketers to understand how the ethnocentrism and attitude of consumers towards foreign brands influence their purchase decision. In order to appeal to the Indian market better, many companies have started using patriotic advertising to evoke patriotic and nationalistic emotions among consumers. One such industry that utilizes such patriotic strategies is the automobile industry. The main objective of the study is to understand the effect that ethnocentrism and attitude towards foreign brands have on consumers purchase of automobiles. To measure the same, a survey consisting of a self-administered questionnaire with a sample size of 108 was conducted. For data analysis purpose, exploratory factor analysis, CART technique and regression analysis have been used in the study. CART technique has been used to develop a model keeping ethnocentrism and attitude as the base. The results of the study show that attitude has turned out to be dominant over ethnocentrism and has a significant role to play in persuading consumers to buy cars of an Indian or a foreign brand. The findings also show that ethnocentrism influences attitude which in turn influences purchase decision. The implications of the study suggest that domestic marketers should imply patriotic advertising in their marketing initiatives and also recommend them to highlight the Made in India tag. The study also suggests foreign marketers operating in the Indian market to focus less on the country-of-origin and focus more on the technicalities of the product because attitude towards foreign brands is a major contributor towards the purchase decision. 2020 Management Development Institute. -
Piperine, an alkaloid of black pepper seeds can effectively inhibit the antiviral enzymes of Dengue and Ebola viruses, an in silico molecular docking study
Ebola and Dengue are the critical diseases caused by RNA viruses, especially in the tropical parts of the globe, including Asia and Africa, and no prominent therapeutic options are available so far. Here, an effort was made to evaluate the efficacy of black pepper (Piper nigrum L.) alkaloid Piperine as a potential drug through computational docking simulation. Eight structurally essential proteins of Dengue and Ebola virus were selected as in silico docking targets for Piperine. Absorption, Distribution, Metabolism, and Excretion profile showed that Piperine was safe and possessed significant drug-like properties. Molecular dynamic simulation and binding free energy calculation showed that Piperine could inhibit Methyltransferase (PDB id 1L9K) of Dengue and VP35 Interferon Inhibitory Domain (PDB id 3FKE) of Ebola virus in comparison with the commercial antiviral Ribavirin. Furthermore, statistical analysis based on multivariate and clustering approaches revealed that Piperine had more affinity towards viral proteins than that of Ribavirin. 2020, Indian Virological Society. -
Exploring the dream pattern among the nightshift workers: A qualitative study
Nightshift workers are increasing day by day, but many times, people forget the health and sleep effects caused by the nightshift. One such impact is the altered circadian rhythm, which is very important for proper functioning of the body and a good sleep. This altered circadian rhythm can have an impact on waking and sleep life of the nightshift workers. This qualitative study is to find the dream pattern among the nightshift workers and to find the frequency in dreaming among this group. Dreams are the reflections of the waking life and dream patterns are seen among groups sharing similar wake life experiences. This study is conducted with nine nightshift and nine dayshift workers, dream journal was used to collect the dreams from the participants. The frequency of dreaming is seen more among the nightshift workers. The dream patterns among both the groups are similar but there are dreams that make the nightshift group different from the dayshift. The dreams of the nightshift group includes mainly their friends and the feelings of being stuck/in danger. Also, their dreams were more fantastic in nature and have more emotional content. The study shows that sexual dreams are seen majorly among the nightshift group. This finding can be further used to conduct researches on the impact of nightshift on the sexual health and overall well being of nightshift workers and the reflection of the same in their dreams. 2020. All Rights Reserved. -
Optimal Feature Selection for the Classification of Hyperspectral Imagery Using Adaptive SpectralSpatial Clustering
Hyperspectral images captured through the hyperspectral sensors play an imperative part in remote sensing applications in the present context. Unlike traditional images sensed with few bands in the visible spectrum, the hyperspectral (HS) images are obtained with hundreds of spectral band ranges from infrared to ultraviolet regions. Because of its vast spatial and spectral data, it requires an extensive computational system for processing and its hidden features are needed to be unveiled in an effective manner specifically for the classification of HS imagery. This approach exploits the high spectral band correlation and rich spatial information of the HS images for the generation of feature vectors. To attain optimal feature space for the best probable classification, an adaptive approach is incorporated to adaptively choose spectralspatial features for feature selection to classify the pixels effectively. Furthermore, the HS image encompasses several bands including noisy bands. To categorize the images with great accuracy, it is suggested to eradicate the noisy bands whilst retaining the informative bands. In this research, an adaptive spectralspatial feature selection scheme is proposed for HS images where the extremely correlated representative bands are considered for analysis with uncorrelated and noisy spectral bands are judiciously discarded during its classification process. This hybrid approach not merely diminishes the computational time and also improves the general classification accuracy significantly. The empirical result displays that the proposed work surpasses the conventional approach of HS image classification systems. 2018, Springer Science+Business Media, LLC, part of Springer Nature. -
Static voltage stability of reconfigurable radial distribution system considering voltage dependent load models
This paper presents the static voltage stability analysis of RDS. Initially the performance of RDS is evaluated using backward/forward load flow considering voltage-dependent load modeling. Later, the load flow solution is used for determining the static voltage stability of the system. The analysis is performed for different type of loads such as constant power, constant current, constant impedance, residential, industrial, commercial, agricultural and electric vehicle loads. The simulations are performed for standard and optimal reconfigured topology of standard IEEE 33-bus test system. The comparative study reveals the importance of load type and topology while assessing the static stability analysis of radial distribution systems. 2020, International Information and Engineering Technology Association. -
Zirconia Supported on Rice Husk Silica from Biowaste: A Novel, Efficient, and Recoverable Nanocatalyst for the Green Synthesis of Tetrahydro-1-benzopyrans
Abstract: Zirconia supported silica from rice husk (an agricultural waste) has been utilized as a novel and efficient heterogeneous catalyst for the synthesis of bioactive tetrahydro-1-benzopyran derivatives via multicomponent condensation of various aldehydes with dimedone and malononitrile. This protocol offers various advantages such as high yields, simple experimental work-up procedure, short reaction time, no by-products, economic availability, easy purification, and reusability of the catalyst. 2020, Pleiades Publishing, Ltd. -
Impact of social-emotional learning intervention on emotional intelligence of adolescents
Adolescents face a variety of challenges, some of which include social, emotional, cognitive, and interpersonal. In order to help them with their emotions, adolescents should be taught a variety of skills to regulate and handle emotions better. With this intent in mind, a social-emotional learning (SEL) intervention module was developed by the researchers. This module covered aspects related to self-awareness, social awareness, responsibility, empathy and decision-making. These components also form the basis for emotional intelligence (EI) which is defined as the ability to perceive, understand, and regulate emotions of oneself and others. The present study aimed to understand if there arises any difference in scores of EI post the SEL intervention. Second, the gender differences with respect to EI were also be analyzed. The EI Scale (2014) was administered to 80 students between the age group of 13-14 years, from a CBSE school in Chennai. These adolescents were selected through the convenience sampling, and the four subscales were also analyzed. The findings from the study revealed a significant difference in scores from pretest to posttest (t = -4.66, P < 0.05). With respect to gender, no significant difference was found. On the subscales, two of four subscales showed significant difference in understanding emotions (Z = -4.63, P < 0.05) and handling emotions (Z = -4.023, P < 0.05). Indian Journal of Social Psychiatry. All Rights Reserved. -
A Review on Flood Prediction Algorithms and A Deep Neural Network Model for Estimation of Flood Occurrence
Flood occurs as often as possible happens due to many environmental changes in our planet in the present years. The occurrence and damages caused by flood is very high. Major cause of flood is due to heavy rainfall which in turn increases the water level of the rivers and other water bodies. The various factors that play a major role in the occurrence of rainfall are rise in temperature, humidity level, dew point, pressure in and around the area of concern, wind speed, etc. In order to reduce the number of victims due to flood it is necessary to have a system to predict flood occurrence. In this paper, we classify and analyzed the various prediction algorithms which show usage of Deep Neural Network produces better results. In addition, a design model has been proposed to predict the flood by training the Deep Neural Network with the above-mentioned factors. 2020, Asian Research Association. All rights reserved. -
Cryptic species and taxonomic troubles: A rebuttal of the systematic treatment of the Asian ladies' tresses orchids (Spiranthes species; Orchidaceae) by Pace et al. (2019)
In a recent research article by Pace et al. (2019), the authors claimed to have used information from phenology, morphology and molecular phylogenetics in their nomenclatural review of the Spiranthes sinensis complex. However, there are several scientific and botanical nomenclature issues with the Pace et al. (2019) paper in addition to its many errors and misinformation, which can be severely misleading and have the potential to affect our understanding of the highly complex Asian Spiranthes group. Here, we compare and critique their study in light of our study published prior to the article in the Botanical Journal of the Linnean Society. We suggest that the authors should have resorted to improved and new molecular data and a truly integrative analysis to support: (1) re-circumscription of the S. sinensis species complex for each of the six species they recognized, and the treatment of S. hongkongensis as a hybrid; and (2) all the new synonymies they proposed for Asian Spiranthes. 2020 The Linnean Society of London, Botanical Journal of the Linnean Society, 2020, 194, 375-381 -
Study of mineral and nutritional composition of some seaweeds found along the coast of Gulf of Mannar, India
The presence of Algae on the Earth is ubiquitous. The industry that widely uses algae is food industry, where the algae are used as a food supplement and also as an addition to the nutrient rich food. This study emphasizes on the mineral and nutritional composition of the selected fourteen algal species which are abundantly found along the coast of the Gulf of Mannar. The selected species of algae belong to different algal families such as Chlorophyta, Phaeophyta and Rhodophyta. The amount of minerals such as Ca, Zn, Fe, K, Mg, Mn, and Cu were estimated by employing the method of acid digestion followed by atomic absorption spectroscopy. We estimated the nutritional content based on the assessment of total protein, carbohydrate, phenol, ash and moisture contents of the algal species. The results based on the analysis of the mineral content in the algal seaweeds depicted that the seaweeds comprised of high amount of the macro minerals and trace minerals. Estimation of nutritional composition revealed that these algal species are rich in protein and carbohydrate. The ash contents were found to be very high in Jania rubens (86.66%), Padina boergesenii (85%) and Valoniopsis pachynema (84%). Based on the present study we infer that the algal seaweeds contained high amount of the nutritional compounds, which might pave the way for a higher standard of nutritional supply to the humans in the future. Jose & Xavier (2020). This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution and reproduction in any medium, provided the original author and source are credited (https://creativecommons.org/licenses/by/4.0/). -
Synthetic polymer hydrogels as potential tissue phantoms in radiation therapy and dosimetry
The efficacy of synthetic polymers as hydrogel phantoms for radiation therapy and dosimetry has been investigated for photon and charged particle (electron, proton and alpha particle) interactions. Tissue equivalence has been studied in terms of photon mass energy-absorption coefficients, KERMA (kinetic energy released per unit mass), equivalent atomic number and energy absorption build-up factors, relative to human tissues (skin, soft tissue, cortical bone and skeletal muscle), in the energy range 0.015-15 MeV. For charged particle interactions, ratio of effective atomic number is examined for tissue-equivalence in the energy region of 10 keV-1 GeV. Well established theoretical formulations are used for computation of photon mass-energy absorption effective atomic number, electron density and KERMA. Five-parameter geometric progression (G-P) fitting approximation is used to compute the values of energy absorption build-up factors. Effective atomic number for charged particle interaction is determined using logarithmic interpolation method. Using the analytical methodology, it has been revealed that all the selected synthetic polymers have good tissue-equivalence relative to all tissue except cortical bone. In particular, polyglycolic acid (PGA) and poly-lactic-co-glycolic acid (PLGA) prove to be best substitute material for photon interactions. On the other hand, % difference between effective atomic number for charged particle relative to human tissues is found least for polyethylene glycol (PEG) demonstrating adequate tissue-equivalence. Therefore, the present study is expected to be useful to choose most appropriate phantom material for radiation therapy. 2020 IOP Publishing Ltd.