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Influence of Solvent Environment on the Photophysical Properties of Maleamic Acid and Maleimide Derivatives
Absorption and fluorescence spectra of novel maleamic acid (E)-4-oxo-4-(4-((2-oxooxazolidin-4-yl)methyl)phenylamino)but-2-enoic acid (OMPBA) and its maleimide derivative 1-(4-((2-oxooxazolidin-4-yl)methyl)phenyl)-1H-pyrrole-2,5-dione (OMPPD) were recorded in a series of eighteen solvents of increasing polarity at room temperature (25C). A large Stokes shift indicates a bathochromic fluorescence band shift for both molecules. The photoluminescence properties and intramolecular charge transfer (ICT) behavior of OMPBA and OMPPD were analyzed. In the case of OMPPD, ICT contributes to a larger extent towards positive solvatochromism compared to OMPBA. Ground-state and singlet excited-state dipole moments of OMPBA and OMPPD were calculated using solvatochromic methods proposed by Bilot and Kawski, Lippert and Mataga, Bakhshiev, Kawskii and Chamma and Viallet, and also Reichardt. The ground state dipole moment was found to be larger than for the singlet excited state for both molecules. Optimized geometry and HOMOLUMO energies of OMPBA and OMPPD have been determined by DFT and TDDFT/B3LYP/6-311G (d, p). The HOMOLUMO energy gap was calculated from cyclic voltammetry and compared with theoretical values with good agreement. GCRD parameters such as ionization potential (IP), electron affinity (EA), electronegativity ?, chemical potential (?), chemical hardness (?), chemical softness (s) and electrophilicity (?) were calculated for OMPBA and OMPPD. 2018, Springer Science+Business Media, LLC, part of Springer Nature. -
Personal fableness and perception of risk behaviors among adolescents
Adolescence is a crucial period where one tends to identify who they are as an individual. However, as a teenager is struggling to find his/her place in this world, it is also a time where they are prone to engaging in risk behaviors, which tend to have an extreme psychological impact. The objective was to explore the experiences of an adolescent who engages in risk behaviors and to understand their level of personal fables. The study was a qualitative design with content analysis with semi-structured interviews of ten male adolescents aged 16-18 years. The major findings of the study indicated that adolescents pattern of thinking revolves around the fact that they are invincible and invulnerable. Furthermore, adolescents are aware of the risks they are putting themselves through and how in the process they are hurting others. The implications of the study are to conduct more life skill programs in schools; greater awareness has to be created on the impact and harmful effects of such behaviors. 2018, Indian Journal of Public Health Research and Development. All rights reserved. -
Synthesis of porous graphene sheets from agricultural waste by chemical methods
A facile technique to synthesise wrinkled graphene like nano carbon (GNC) agricultural waste like wood and coconut charcoal is reported in the current study. The charcoal is produced by thermal decomposition of wood and coconut shell and is intercalated by Hummer's method. It is separated by centrifugation and sonication to get few layer graphene sheets. The structural and chemical changes of the nanostructure are elucidated by Raman spectroscopy, TEM, SEMEDS and XPS. Raman spectra revealed the existence of highly graphitized amorphous carbon, which is confirmed by the appearance of five peaks in the deconvoluted first order Raman spectra. The SEM analysis reveals the formation of large area graphene sheets with nanoporous structure in it. The TEM/SAED analysis exhibits the presence of short range few layers graphene. 2018 World Research Association. All rights reserved. -
Nonlinear convection in nano Maxwell fluid with nonlinear thermal radiation: A three-dimensional study
The combined effects of nonlinear thermal convection and radiation in 3D boundary layer flow of non-Newtonian nanofluid are scrutinized numerically. The flow is induced by the stretching of a flat plate in two lateral directions. The mechanism of heat and mass transport under thermophoretic and Brownian motion is elaborated via implementation of the thermal convective condition. The prevailing two-point nonlinear boundary value problem is reduced to a two-point ordinary differential problem by employing suitable similarity transformations. The solutions are computed by the implementation of homotopic scheme. At the end, a comprehensive parametric study has been conducted to analyze the typical trend of the solutions. It is found that the nanoparticle volume fraction and temperature profiles are stronger for the case of solar radiation in comparison with problem without radiation. 2017 Faculty of Engineering, Alexandria University -
A pair of kinematically related space curves
We investigate the relation between two types of space curves, the Mannheim curves and constant-pitch curves and primarily explicate a method of deriving Mannheim curves and constant-pitch curves from each other by means of a suitable deformation of a space curve. We define a "radius" function and a "pitch" function for any arbitrary regular space curve and use these to characterize the two classes of curves. A few non-trivial examples of both Mannheim and constant pitch curves are discussed. The geometric nature of Mannheim curves is established by using the notion of osculating helices. The Frenet-Serret motion of a rigid body in theoretical kinematics is studied for the special case of a Mannheim curve and the axodes in this case are deduced. In particular, we show that the fixed axode is developable if and only if the motion trajectory is a Mannheim curve. 2018 World Scientific Publishing Company. -
A New Facile Iodine-Promoted One-Pot Synthesis of Dihydroquinazolinone Compounds
A one-pot iodine catalyzed reaction has been developed for the preparation of dihydroquinazolinones from isatoic anhydride, enaminones, and amines in modest to good yields. The reaction has been screened in various catalysts and solvents and a gram scale experiment has been performed based on the optimum conditions. A possible mechanism has been proposed based on the control experiments. The reaction has been checked with broad range of substrates. 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim -
The Diffuse Radiation Field at High Galactic Latitudes
We have used GALEX observations of the north and south Galactic poles to study the diffuse ultraviolet background at locations where the Galactic light is expected to be at a minimum. We find offsets of 230-290 photon units in the far-UV (1531 and 480-580 photon units in the near-UV (2361 . Of this, approximately 120 photon units can be ascribed to dust-scattered light and another 110 photon units (190 in the near-UV) to extragalactic radiation. The remaining radiation is, as yet, unidentified and amounts to 120-180 photon units in the far-UV and 300-400 photon units in the near-UV. We find that molecular hydrogen fluorescence contributes to the far-UV when the 100 ?m surface brightness is greater than 1.08 MJy sr-1. 2018. The American Astronomical Society. All rights reserved. -
Heat transfer in the flow of blood-gold Carreau nanofluid induced by partial slip and buoyancy
Dynamics of blood containing gold nanoparticles on a syringe and other objects with a nonuniform thickness is of importance to experts in the industry. This study presents the significance of partial slip (i.e. combination of linear stretching and velocity gradient) and buoyancy on the boundary layer flow of blood-gold Carreau nanofluid over an upper horizontal surface of a paraboloid of revolution (uhspr). In this report, the viscosity of the Carreau fluid corresponding to an infinite shear-rate is assumed as zero, meanwhile, the viscosity corresponding to zero shear-rate, density, thermal conductivity, and heat capacity were assumed to vary with the volume fraction of nanoparticles. The governing equation that models the transport phenomenon were non-dimensionalized and parameterized using suitable similarity variables and solved numerically using classical RungeKutta method with shooting techniques and MATLAB bvp4c package for validation. The results show that temperature distribution across the flow decreases more significantly with buoyancy-related parameter when the influence of partial slip was maximized. Maximum velocity of the flow is ascertained at larger values of partial slip and buoyancy parameters. At smaller values of Deborah number and large values of volume fraction, maximum local skin friction coefficient, and local heat transfer rate are ascertained. 2018 Wiley Periodicals, Inc. -
Medical Image Security Using Dual Encryption with Oppositional Based Optimization Algorithm
Security is the most critical issue amid transmission of medical images because it contains sensitive information of patients. Medical image security is an essential method for secure the sensitive data when computerized images and their relevant patient data are transmitted across public networks. In this paper, the dual encryption procedure is utilized to encrypt the medical images. Initially Blowfish Encryption is considered and then signcryption algorithm is utilized to confirm the encryption model. After that, the Opposition based Flower Pollination (OFP) is utilized to upgrade the private and public keys. The performance of the proposed strategy is evaluated using performance measures such as Peak Signal to Noise Ratio (PSNR), entropy, Mean Square Error (MSE), and Correlation Coefficient (CC). 2018, Springer Science+Business Media, LLC, part of Springer Nature. -
Quadratic convective flow of radiated nano-Jeffrey liquid subject to multiple convective conditions and Cattaneo-Christov double diffusion
A nonlinear flow of Jeffrey liquid with Cattaneo-Christov heat flux is investigated in the presence of nanoparticles. The features of thermophoretic and Brownian movement are retained. The effects of nonlinear radiation, magnetohydrodynamic (MHD), and convective conditions are accounted. The conversion of governing equations into ordinary differential equations is prepared via stretching transformations. The consequent equations are solved using the Runge-Kutta-Fehlberg (RKF) method. Impacts of physical constraints on the liquid velocity, the temperature, and the nanoparticle volume fraction are analyzed through graphical illustrations. It is established that the velocity of the liquid and its associated boundary layer width increase with the mixed convection parameter and the Deborah number. 2018, Shanghai University and Springer-Verlag GmbH Germany, part of Springer Nature. -
A complete person re-identification model using Kernel-PCA-based Gabor-filtered hybrid descriptors
Person re-identification is a challenging problem in computer vision. Lots of research interest is observed in this area over the past few years. A model for complete person re-identification can prove useful in this direction. Use of convolutional neural networks for pedestrian detection can improve the accuracy of detection to a larger extent. Deriving a descriptor which is invariant to the changes in the illumination, background and the pose can make the difference in the re-identification process. The predominant part of our work focuses on building a robust descriptor which can tackle such challenges. We have concentrated on building a descriptor by employing appearance-based features extracted both at local and global levels. Further, the dimensionality of the descriptor is reduced using kernel PCA. Distance metric learning algorithms are used to evaluate the descriptor on three major benchmark datasets. We propose a complete person re-identification system which involves both pedestrian detection and person re-identification. Major contributions of this work are to detect pedestrians from surveillance videos using CNN-based learning and to generate a kernel-PCA-based spatial descriptor and evaluate the descriptor using known distance metric learning methods on benchmark datasets. 2018, Springer-Verlag London Ltd., part of Springer Nature. -
Assessment of microsatellite instability for screening bladder cancer in high-risk population
Aims: This study aims to determine the diagnostic efficacy of microsatellite markers for screening bladder cancer in population at high risk. Materials and Methods: A population of 200 people was screened for bladder cancer using a set of microsatellite markers. Urine samples were obtained from four different types of population groups - Group 1 (healthy population group), Group 2 (current smokers with a smoking history of more than 10 years), Group 3 (bladder cancer group), and Group 4 (bladder cancer group who were former smokers with a history of more than 10 years). Polymerase chain reaction (PCR) was performed to amplify microsatellite sequences at D9S63, D9S156, and D9S283. PCR products were separated on 1.8% agarose gel and were scanned using ultraviolet transilluminator. Results: In Group 2 (high-risk population group, mainly current smokers with a history of more than 10 years), microsatellite alterations were found in 36 out of 50 people. We observed microsatellite alterations in 38 out of 50 people in Group 3 (bladder cancer group) and in 39 out of 50 people in Group 4 (bladder cancer group, mainly former smokers with a history of more than 10 years). The sensitivity of this test in Group 2, Group 3, and Group 4 was found to be 72%, 76% and 78%, respectively. The specificity of this test in each group was found to be 90%. Conclusion: Using these set of microsatellite markers, medium sensitivity and high specificity were reported for this test. The current findings suggest that a set of microsatellite markers (D9S63, D9S156, and D9S283) can be used to detect bladder cancer in high-risk population. 2018 Medknow Publications. All Rights Reserved. -
Opto-electric property relationship in phosphorus embedded nanocarbon
Graphene, due to its zero band gap, has an excellent combination of the important features such as ballistic transport, tensile strength and chemical tuning, which are practically hindered in opto-electric applications. The precursors used in the production of nanocarbon are relatively costlier; however, that their production processes include difficulties is a harder problem. It is possible to control the size, structure and properties of the produced nanocarbon matrix by tuning sp2 domains in the matrix. In this respect, the coal, being a potential candidate for the synthesis of nanocarbon which holds promising applications, has attracted remarkable interest. The nanocarbon structure reported in this paper was synthesized from bituminous coal and then phosphorus atoms were added into the produced structure in order to obtain resultant composite structure, whose structural properties were illustrated here in detail by using the X-ray, IR and UVVisible spectroscopy techniques. A systematical analysis of the optical and electrical properties of the produced composite has revealed that a composite structure to be produced in the ratio 1:2 of nanocarbon + phosphorus has better optical and electrical properties. We report here that the composite produced in this study from nanocarbon by adding phosphorous atoms shows unique photoluminescent property in particular due to the dominance of quantum confinement and oxygen functionalities. The observed increase in the dielectric strength, which results from interfacial polarization and its frequency independent nature, is desirable for the fields such as supercapacitor, sensor, stealth applications etc. 2018 The Authors -
FSDA: Framework for Secure Data Aggregation in wireless sensor network for enhancing key management
An effective key management plays a crucial role in imposing a resilient security technique in Wireless Sensor Network (WSN). After reviewing the existing approaches of key management, it is confirmed that existing approachs does not offer good coverage on all potential security breaches in WSN. With WSN being essential part of Internet-of-Things (IoT), the existing approaches of key management can definitely not address such security breaches. Therefore, this paper introduces a Framework for Secure Data Aggregation (FSDA) that hybridizes the public key encryption mechanism in order to obtain a novel key management system. The proposed system does not target any specific attacks but is widely applicable for both internal and external attacks in WSN owing to its design principle. The study outcome exhibits that proposed FSDA offers highly reduced computational burden, minimal delay, less energy consumption, and higher data transmission perforance in contrast to frequency used encryption schemes in WSN. Copyright 2018 Institute of Advanced Engineering and Science. All rights reserved. -
Nonlinear radiative flow of casson nanoliquid past a cone and wedge with magnetic dipole: Mathematical model of renewable energy
Solar energy is an important source of energy for all the living things. Other sources of energy such as electricity and heat can be converted from solar radiation. The recent advanced technologies are utilized to convert solar energy into electricity. In this direction, nanoliquids are quite useful because they directly absorb or scatter solar radiation. Nanofluids are selected to be best aspirant for the development of renewable energy. They are successfully utilized in the processes of renewable energy. Due to such importance of nanofluids, we investigate the effects of nanoparticles on nonlinear convective and radiative flow of Casson liquid. Two cases are considered namely flow due to a cone and flow due to a wedge. In addition to traditional temperature dependent heat source aspect an exponential space dependent heat source effect is examined. Explicitly heat/mass transfer mechanism is analysed due to prescribed linear surface temperature/particles volume fraction. Problem formulation is presented using conservation laws of mass, momentum, energy and nanoparticles volume fraction under boundary layer approximations. The solutions to the dimensionless problem are computed via Runge-Kutta-Fehlberg based shooting method. Results are plotted and examined. The exponential space dependent and thermal dependent heat source aspects are dominates on thermal field. Further, heat and mass transfer rates are higher in case of flow created by cone than flow created by wedge. The liquid velocity is higher in the case of flow due to wedge than flow due to cone case. 2018 by American Scientific Publishers All rights reserved. -
A study of pulsation & rotation in a sample of A-K type stars in the Kepler field
We present the results of time-series photometric analysis of 15106 A-K type stars observed by the Kepler space mission. We identified 513 new rotational variables and measured their starspot rotation periods as a function of spectral type and discuss the distribution of their amplitudes. We examined the well-established period-color relationship that applies to stars of spectral types F5-K for all of these rotational variables and, interestingly, found that a similar period-color relationship appears to extend to stars of spectral types A7 to early-F too. This result is not consistent with the very foundation of the period-color relationship. We have characterized 350 new non-radial pulsating variables such as A- and F-type candidate ? Scuti, ? Doradus and hybrid stars, which increases the known candidate non-radial pulsators in the Kepler field significantly, by ?20%. The relationship between two recently constructed observables, Energy and Efficiency, was also studied for the large sample of non-radial pulsators, which shows that the distribution in the logarithm of Energy (log (En)) can be used as a potential tool to distinguish between the non-radial pulsators, to some extent. Through visual inspection of the light curves and their corresponding frequency spectra, we found 23 new candidate red giant solar-like oscillators not previously reported in the literature. The basic physical parameters such as masses, radii and luminosities of these solar-like oscillators were also derived using asteroseismic relations. 2018, The Author(s). -
Psychological distress among college students of coastal district of Karnataka: A community-based cross-sectional survey
Background: Common Mental Disorders (CMDs) are frequent among adolescents and early adults. National Mental Health Survey of India 20152016 shows alarming results, especially for depression. This study explored the prevalence of psychological distress among college students. Additionally, the relationship between gender, living arrangement with psychological distress in various educational streams were explored. Materials and Methods: Through a cross-sectional community-based survey a total of 4839 college going students of various educational streams in Mangalore, Karnataka were assessed for psychological distress with Self-Reporting Questionnaire (SRQ-20). Results: Participants had median age of 19 (range = 9) years and the majority (59.5%) were females. The median SRQ score was 4 (range 20) and about 28.5% of students were found to be psychologically stressed. The suicidal ideation was reported by 13.6% of the students. Engineering and Arts/science/commerce students had significantly higher psychological distress scores as compared to health and allied sciences (k = 47.7; p < 0.001) and those who were staying with families (U = 2,687,648.5; p = 0.004) reported higher levels of psychological distress in comparison to those who were staying away from their families. Conclusion: Prevalence of psychological distress was high among students, especially non-medical students, students who were staying with their families, and those who were younger in age. A significant proportion of students had suicidal ideation, which needs early mental health interventions at the college level. 2018 -
Challenges of Indian girls with maternal schizophrenia
Schizophrenia, earlier known as dementia praecox, is considered to be one of the most devastating mental illnesses due to its impact on the individual as well as family members. The Indian context characterized by ones rootedness to family, warrant enquiry about difficulties and burnouts faced by girl children.When it is the mother who is suffering from the illness, there tends to be a huge lag in terms of primary care giving. A disturbed home environment along with inadequate parenting have shown to adversely affect the girl children. The present qualitative research study aimed to explore challenges faced by the girl children with maternal schizophrenia with the help of 43 Mental Health Professionals (MHPs) across India. Interpretative Phenomenological Approach (IPA)was adopted and interviews were conducted using a validated interview guide. Thematic analysis revealed that girl children whose mothers are diagnosed with schizophrenia faced challenges in self, family and social sphere of life. Neglect, self blame and the question why me were recurrent themes.They experienced difficulties in cognitive, behavioral and social domains. The added burden of family responsibilities and social stigma made the surroundings challenging.Exploring the world of girls with maternal schizophrenia would deepen our understanding about impact of schizophrenia on family members and aid us develop interventions to support the care givers. 2019 Oriental Scientific Publishing Company. All rights reserved. -
Exploratory analysis of legal case citation data using node embedding
Legal case citation network is primary tool to understand mutable landscape of the legal domain. These networks are also used to study legal knowledge transfer, similar precedents and inter-relationship among laws of a judiciary. These networks are often very huge and complex due to the multidimensional texture of this domain. In recent years, network embedding using deep learning emerges as a promising breakthrough for analyzing networks. This paper presents a novel approach of learning vector representation for a legal case based on its citation context in the network using node2vec algorithm. These vector embedding are further used in understanding similarities between cases. Paper highlights that the tSNE reduced representation of the obtained vectors facilitates visual exploration and provides insights into the complex citation network. Suitability of node embedding for application of machine learning algorithm is demonstrated by clustering the node vectors for finding similar cases. ICIC International 2019. -
Photophysical and Electrochemical Studies of Anchored Chromium (III) Complex on Reduced Graphene Oxide via Diazonium Chemistry
Covalently anchored chromium complex on reduced graphene oxide (rGO-Cr) is successfully synthesised through trimethoxy silyl propanamine (TMSPA) and phenyl azo salicylaldehyde (PAS) coupling. The rGO-Cr is characterised by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), electron dispersive analysis of X-rays (EDAX), Raman spectroscopy, scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HRTEM). Absorption and emission properties of rGO-TMSPA-PAS are studied by excitation dependent photoluminescence emissions at room temperature. Electrochemical sensing activity of rGO-Cr is monitored for paracetamol using modified glassy carbon electrode. Cyclic voltammetry measurements indicated that rGO-Cr substantially enhance the eletrochemical response of paracetamol. The experimental factors are investigated and optimized. 2019 John Wiley & Sons, Ltd.