Browsing by Author "S.K. Mishra"

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3rd International Joint Conference on Computational Sciences and Optimization, CSO 2010: Theoretical Development and Engineering Practice: Message from general co-chairs and program co-chairs
(2010) K.K. Lai; Yingwen Song; Shouyang Wang; W.K. Ching; Hai Jin; Jianping Li; S.K. Mishra; Lean Yu
[No abstract available]
5-Amino uracil activated silver nano resonators for highly selective visual detection of dopamine and as an agonist towards BAP: Promoting shoot growth in Bacopa monnieri L.
(Elsevier B.V., 2024) Saumya Singh; Raksha Singh; Anurag Kumar Singh; Minu Yadav; S.K. Mishra; Jyoti Dixit; Pooja Verma; K.N. Tiwari; K.K. Upadhyay
Silver nanoparticles (AgNPs) with an average size of about 17.5 nm have been synthesized using 5-amino uracil as a reducing and capping agent. The concentration of these AgNPs was worked out to be 48 nM. These AgNPs served as a highly selective optical sensor against an important neurotransmitter like dopamine (DA) at its nano molar level (94 nM) with the linearity range of 1–5 µM. The quantification of DA in one of its injection sample was also achieved with a recovery of 91 %. Studies like FTIR, UV–Vis, XPS, SEM, TEM, EDX, DLS and Zeta potential measurements have supported our findings. Significant amplification in the Raman signal of DA was also observed upon its addition into as prepared AgNPs solution. Moreover, these AgNPs seemed to augment the activity of cytokinin (BAP) in synergistic fashion and enhanced in vitro high frequency shoots regeneration in B. monnieri L. and also led to increment in its antioxidant metabolite contents like phenol and flavonoid. © 2023 Elsevier B.V.
A derivative for semipreinvex functions and its applications in semipreinvex programming
(Springer International Publishing, 2011) Y.X. Zhao; S.Y. Wang; L. Coladas Uria; S.K. Mishra
A directional derivative concept is introduced to develop Fritz–John and Kuhn–Tucker conditions for the optimization of general semipreinvex functions. The relationship between the optimization problem and the corresponding semiprevariational inequality problem is also shown. © Springer Science+Business Media, LLC 2011.
A low cost yet highly sensitive silver nanoprobe for naked eye detection and determination of bisulphate (HSO4-) in a few real samples
(Elsevier B.V., 2022) Raksha Singh; Minu Yadav; Anurag Kumar Singh; S.K. Mishra; K.K. Upadhyay
Herein, we report a simple and economical yet highly sensitive and efficient silver nanoresonators based protocol for naked eye detection of a janus-faced ion like bisulphate from its two real samples in real time. The SEM-TEM, DLS, AFM and EDAX alongwith spectroscopic studies have further substantiated our observation in the same context. The quantification of bisulphate in one of its real sample through UV–Vis spectroscopy using these nanoprobes as indicator has also been carried out successfully. The Raman measurements have clearly indicated the rich SERS potential of these silver nanoresonators. © 2022 Elsevier B.V.
A Note on the Paper "On Approximately Star-Shaped Functions and Approximate Vector Variational Inequalities"
(Springer Science and Business Media, LLC, 2013) S.K. Mishra; Vivek Laha
In this note, we take care of a gap in Remark 2.1 of Mishra and Laha ("On approximately star-shaped functions and approximate vector variational inequalities", Mishra and Laha in J. Optim. Theory Appl. 156:278-293, 2013) and modify the corresponding results. © 2013 Springer Science+Business Media New York.
A weighted version of Hermite-Hadamard type inequalities for strongly GA-convex functions
(Institute of Advanced Science Extension (IASE), 2020) Nidhi Sharma; S.K. Mishra; A. Hamdi
In this paper, we have established new weighted Hermite-Hadamard type inequalities for strongly GA-convex functions. Those findings are obtained by using geometric symmetry of continuous positive mappings and differentiable mappings whose derivative in absolute value are strongly GAconvex. Some previous results are special cases of the results obtained in this paper. © 2020 The Authors.
An ab initio study of electronic structure and spectra of 8-bromoguanine: A comparative study with guanine
(Elsevier, 2001) S.K. Mishra; P.C. Mishra
Ground state geometries of the four tautomeric forms keto-N9H, keto-N7H, enol-N9H and enol-N7H of 8-bromoguanine (8BG) were optimized using the ab initio RHF procedure employing a mixed basis set consisting of the 6-311 + G* basis set for the nitrogen atom of the amino group and the bromine atom, and the 4-31G basis set for all other atoms. These calculations were followed by correlation correction of the total energy at the MP2 level using the same basis set. The different tautomeric forms of 8BG in the ground state were solvated using the isodensity surface polarized continuum model (IPCM) of the SCRF theory both at the RHF and MP2 levels. Excited states were generated employing configuration interaction among singly excited configurations (CIS) obtained using a limited window of filled and empty molecular orbitals. Formation of hydrogen-bonded complexes between 8BG and three water molecules in the ground and excited states was considered in order to account for solvent effects approximately. Excited state geometry was optimized in each case for the lowest singlet excited state which was found to be of π-π* type. Vibrational frequency analysis was performed in order to ensure that the stationary points located on the potential energy surfaces by geometry optimization were minima. It is found that 8BG would occur in the ground state dominantly in the keto-N7H form both at the aqueous solution-air interface and inside the bulk liquid. The observed absorption and fluorescence spectra of 8BG can be explained satisfactorily considering only the keto-N7H form of the molecule. The enol tautomers of 8BG do not appear to be important from the point of view of ground state properties or electronic spectra. The observed differences between the behaviors of guanine and 8BG can be easily explained on the basis of the results obtained. © 2001 Elsevier Science B.V. All rights reserved.
An Ab Initio Study of Excited States of Guanine in the Gas Phase and Aqueous Media: Electronic Transitions and Mechanism of Spectral Oscillations
(John Wiley and Sons Inc., 2000) M.K. Shukla; S.K. Mishra; Anil Kumar; P.C. Mishra
[No abstract available]
An ab initio theoretical study of electronic structure and properties of 2′-deoxyguanosine in gas phase and aqueous media
(John Wiley and Sons Inc., 2002) S.K. Mishra; P.C. Mishra
Molecular geometries of two structural forms of 2′-deoxyguanosine (keto-N9R and keto-N7R, R = the sugar moiety) considering both the C2′-endo and C3′-endo conformations of the sugar ring and those of the complexes of these species with two water molecules each were optimized employing the ab initio RHF procedure. A mixed basis set consisting of the 6-311+G* basis set for the nitrogen atom of the amino group and the 4-31G basis set for all the other atoms was used. The RHF calculations were followed by correlation correction of the total energy at the MP2 level. Both the structural forms of 2′-deoxyguanosine were solvated using the polarized continuum model (PCM) of the self-consistent reaction field (SCRF) theory and the corresponding RHF optimized geometries at the RHF and MP2 levels. Geometry optimization was also performed in aqueous media using the Onsager model at the RHF level using the above-mentioned mixed basis set, and subsequently, using the reoptimized geometries, single-point MP2 calculations were performed. It is found that both the keto-N9R and keto-N7R forms of 2′-deoxyguanosine as well as their complexes with two water molecules each would occur, particularly at the water-air interface. Though the normal Watson-Crick-type base pairing would not be possible with the keto-N7R form of 2′-deoxyguanosine(G*), two other (G*-C and G*-T) base pairing schemes may occur with this form of the nucleoside, which may cause mutation. The present calculated geometry of the keto-N9R form of the anti-conformation of 2′-deoxyguanosine including the dihedral angle χCN agree satisfactorily with the available crystallographic results. The present results also agree satisfactorily with those obtained by other authors earlier for the keto-N9R form of 2′-deoxyguanosine using B3LYP and MP2 methods employing the 6-31G* basis set. Using transition state calculations, it is shown that tautomerism of guanine and other similar molecules where the tautomers would coexist would be facilitated by the occurrence of the H+ and OH- fragments of water molecules. Further, this coexistence of the two tautomers appears to make the C8 carbon atom located between the N7 and N9 nitrogen atoms susceptible to attack by the OH- group. Thus, an explanation is obtained for the efficient formation of the reaction product 8-hydroxy-2′-deoxyguanosine, which serves as a biomarker for oxidative damage to DNA in biological systems.
Anticonvulsant study of Capparis zeylanica Linn. Root in Wistar rats
(2012) S.K. Mishra; P.N. Singh; S.D. Dubey
The phytochemical screening reveals the presence of phenol, tannins, flavonoids, fatty acids, saponins etc. in ethanolic extracts of Capparis zeylanica root which was confirmed by the used of various reagents and TLC chromatography. The aim of this study was to evaluate the effects of the ethanol extract of Capparis zeylanica roots (EECZ) in animal models of epilepsy. The ethanolic extract of Capparis zeylanica Linn. (EECZ) was subjected to acute toxicity and then screened for anticonvulsant activity on Maximal Electroshock (MES) and Pentylenetetrazole PTZ) induced seizures models in albino Wistar rats. The extract was found non toxic up to the recommended dose 2000 mg kg-1 b.wt. orally as per OECD guidelines No. 423. For the acute study, in the maximal electroshock seizure model, the administration of 100 mg kg-1 of EECZ resulted in the complete abolition of seizures in 33.65% of the rats and this was increased to 82.51% with the administration of 400 mg kg-1. In the pentylenetetrazole-induced seizure model, 20% protection from mortality was obtained by administration of 100 mg kg-1 and 36% from 200 mg kg-1 EECZ whereas, 80% rats were protected with the administration of 400 mg kg-1. For the chronic study, in the maximal electroshock seizure model, the administration of 100 mg kg-1 EECZ resulted in the complete abolition of seizures in 12.76% of the mice and in 80%, with the administration of 400 mg kg-1. In the pentylenetetrazole-induced seizure model, 15% of the mice were protected from mortality with 100 mg kg-1 EECZ and 85%, with 400 mg kg-1 EECZ. These findings indicate that EECZ consists of anticonvulsant effect and is comparable to clinically used antiepileptic drugs (diazepam and phenytoin). © 2012 Academic Journals Inc.
Approximate stationary conditions for multiobjective mathematical programs with equilibrium constraints
(International Publications, 2020) J.K. Maurya; Kunwar V. K. Singh; S.K. Mishra
In this paper, we establish approximate proper efficient stationary conditions for multiobjective mathematical programs with equilibrium constraints and propose some constraint qualifications under which approximate proper efficient stationary conditions coincide on already existed traditional stationary conditions for multiobjective mathematical programs with equilibrium constraints. © 2020, International Publications. All rights reserved.
Approximate treatment of the plane hydraulic jump with separation zone above the flow zone; [Traitement approximate du ressaut hydraulique avec zone de separation au-dessus de la zone de courant]
(1984) K.S. Karki; S.K. Mishra
[No abstract available]
Asymptotic behaviours of a class of integral transforms in complex domains
(1989) R.S. Pathak; S.K. Mishra
[No abstract available]
Barium-induced contraction of rat vas deferens in calcium-free solution
(1988) S.K. Mishra; P.K. Das; A.K. Sanyal
Barium-induced contraction of smooth muscle through membrane depolarization is well known. Participation of calcium in Ba2+-induced contraction of smooth muscle has been emphasized. The source of the activator Ca2+ translocated by Ba2+ is, however, equivocal. The present study employing whole rat vas deferens, compared the Ba2+ response of the tissue bathed in Ca2+-deprived salt solution with those in normal salt solution. The results indicate that 'phasic' component of Ba2+-induced contraction was due to both mobilization of intracellular calcium and influx of extracellular calcium, which is bound to the membrane while the 'tonic' component was entirely due to the influx of the extracellular calcium of the medium. The results also suggest that Ba2+ might induce a contraction independent of Ca2+. This Ca2+-independent Ba2+ contraction is blocked by verapamil. The data has been interpreted to suggest that the calcium channels in rat vas deferens might be of two types- 'fast' and 'slow' voltage dependent channels- and that fast channels might be more responsible to transmit Ca2+ for phasic component and slow channels for tonic component.
Duality for nonsmooth semi-infinite programming problems
(2012) S.K. Mishra; M. Jaiswal; Le Thi Hoai An
This paper deals with nonsmooth semi-infinite programming problem which in recent years has become an important field of active research in mathematical programming. A semi-infinite programming problem is characterized by an infinite number of inequality constraints. We formulate Wolfe as well as Mond-Weir type duals for the nonsmooth semi-infinite programming problem and establish weak, strong and strict converse duality theorems relating the problem and the dual problems. To the best of our knowledge such results have not been done till now. © 2010 Springer-Verlag.
Duality in Multiobjective Mathematical Programs with Equilibrium Constraints
(Springer, 2021) Kunwar V. K. Singh; J.K. Maurya; S.K. Mishra
In present article, we study a special class of nonlinear programming problems known as multiobjective mathematical programs with equilibrium constraints. We propose Wolfe type and Mond-Weir type dual models for multiobjective mathematical program with equilibrium constraints and establish fundamental duality results. Furthermore, we construct some examples to favor our established results. © 2021, The Author(s), under exclusive licence to Springer Nature India Private Limited.
Duality models for multiobjective semiinfinite fractional programming problems involving type-I and related functions
(Taylor and Francis Ltd., 2019) Pooja Gupta; S.K. Mishra; R.N. Mohapatra
In this paper, we consider several dual models for a multiobjective semiinfinite fractional programming problem and establish usual duality theorems involving type-I and related functions. Our results generalize the results of Zalmai and Zhang [G.J. Zalmai and Qing-hong Zhang, Parametric duality models for semiinfinite multiobjective fractional programming problems containing generalized (α, η, ρ)-V-invex functions, Acta Math. Appl. Sinica29(2) (2013), 225–240]. Results obtained in this paper extend and unify several results in the literature. © 2018, © 2018 NISC (Pty) Ltd.
Duality results for interval-valued semiinfinite optimization problems with equilibrium constraints using convexificators
(Institute for Ionics, 2022) K.K. Lai; S.K. Mishra; Mohd Hassan; Jaya Bisht; J.K. Maurya
This paper deals with the study of interval-valued semiinfinite optimization problems with equilibrium constraints (ISOPEC) using convexificators. First, we formulate Wolfe-type dual problem for (ISOPEC) and establish duality results between the (ISOPEC) and the corresponding Wolfe-type dual under the assumption of ∂∗-convexity. Second, we formulate Mond–Weir-type dual problem and propose duality results between the (ISOPEC) and the corresponding Mond–Weir-type dual under the assumption of ∂∗-convexity, ∂∗-pseudoconvexity, and ∂∗-quasiconvexity. © 2022, The Author(s).
Effect of particle size on the ferroelectric behaviour of tetragonal and rhombohedral Pb(ZrxTi1-x)O3 ceramics and powders
(1995) S.K. Mishra; D. Pandey
The effect of particle size on the structure and ferroelectric behaviour of PZT powders and ceramics with bulk tetragonal and rhombohedral compositions is reported. To our knowledge, this is the first report of particle size effects for the rhombohedral PZT composition. It is pointed out that, below a certain critical size, the formation of ferroelectric domains is not energetically favourable. As a result, the ferroelectric transition may be suppressed due to depolarization and/or elastic energy contributions.
Efficiency and duality in nonsmooth multiobjective fractional programming involving η -pseudolinear functions
(Faculty of Organizational Sciences, Belgrade, 2012) S.K. Mishra; B.B. Upadhyay
In this paper, we shall establish necessary and sufficient conditions for a feasible solution to be efficient for a nonsmooth multiobjective fractional programming problem involving η - pseudolinear functions. Furthermore, we shall show equivalence between efficiency and proper efficiency under certain boundedness condition. We have also obtained weak and strong duality results for corresponding Mond-Weir subgradient type dual problem. These results extend some earlier results on efficiency and duality to multiobjective fractional programming problems involving pseudolinear and η - pseudolinear functions.