Browsing by Author "Sanjeev Kumar Singh"

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An analytical approach to evaluate effective coefficients of 1-3 piezoelectric composites
(World Scientific, 2022) Sanjeev Kumar Singh; Saroja Kanta Panda
In this paper, a micromechanics method is developed to evaluate effective coefficients of piezoelectric fiber-reinforced composites. An exact solution is derived for effective elastic, piezoelectric and dielectric coefficients of such piezocomposites subjected to the applied load in the direction transverse to the fiber orientation. Simultaneously, based on finite element method, a numerical study is performed on a representative volume element of such piezo composite containing fiber in square packing arrangement. The finite element method provides a numerical solution to evaluate effective elastic, piezoelectric and dielectric coefficients for discrete volume fraction of fiber, the range being 0.1-0.6 for this study. The results are interpolated to understand the overall behavior of such piezocomposites. The results obtained from the micromechanics method and the finite element method are compared with the results obtained from other models based on strength of materials method given in the literature. It is observed that the method developed in this study provides better results for effective coefficients susceptible to fiber packing arrangements. © 2022 World Scientific Publishing Europe Ltd.
Approximate-karush-kuhn-tucker conditions and interval valued vector variational inequalities
(World Scientific and Engineering Academy and Society, 2020) Kin Keung Lai; Sanjeev Kumar Singh; Shashi Kant Mishra
This Article deals with the Approximate Karush-Kuhn-Tucker (AKKT) optimality conditions for interval valued multiobjective function as a generalization of Karush-Kuhn-Tucker optimality conditions. Further, we establish relationship between vector variational inequality problems and multiobjective interval valued optimization problems under the assumption of LU−convex smooth and nonsmooth objective functions. © 2020 World Scientific and Engineering Academy and Society. All rights reserved.
Chitosan film of thiolated TPGS-modified Au-Ag nanoparticles for combating multidrug-resistant bacteria
(Elsevier B.V., 2024) Chandrashekhar Singh; Abhishesh Kumar Mehata; Matte Kasi Viswanadh; Punit Tiwari; Rajesh Saini; Sanjeev Kumar Singh; Ragini Tilak; Kavindra Nath Tiwari; Madaswamy S. Muthu
The widely used vitamin-E based amphiphilic material, tocopheryl polyethylene glycol succinate (TPGS) was further improvised to redox-sensitive thiolated TPGS (TPGS-SH), which has been achieved by attaching 4-aminothiophenol. Further, TPGS and TPGS-SH-coated bimetallic gold-silver nanoparticles (TPGS-Au-Ag-NP and TPGS-SH-Au-Ag-NP) were formulated to explore their antibacterial and wound healing abilities. The prepared NP were monodisperse with a mean hydrodynamic diameter of 69.5±3.23 nm, 59.65±3.23 nm, PDI of 0.3±0.05, 0.2±0.03 and a zeta potential of +29.2±2.71 mV and +35.28±1.53 mV, respectively. The TPGS and TPGS-SH modified Au-Ag-NP were tested for their antibacterial efficacy against methicillin-resistant Staphylococcus aureus (MRSA) and E. coli; minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) results showed that TPGS Au-Ag-NP, TPGS-SH-Au-Ag-NP displayed significantly stronger antibacterial activity than their coating material alone. The anti-efflux pump activity of the most potent antibacterial agent TPGS-SH-Au-Ag-NP was evaluated against MRSA. Toxicity assessment of TPGS-SH-Au-Ag-NP in human dermal fibroblasts showed 88% viability up to 125 µg/mL. The TPGS-SH-Au-Ag-NP, after incorporation in chitosan film (TPGS-SH-Au-Ag-NP-CS), exhibited sustained release and prolonged in vivo residence characteristics, which were evaluated by IVIS. Results also revealed that treatment with TPGS-SH-Au-Ag-NP showed a significant 87% wound healing rate after 12 days of application in the rat model. Hence, we concluded that TPGS-SH-Au-Ag-NP was safe and effective against test bacteria MRSA and capable of efficient wound healing when incorporated in chitosan film. © 2024 Elsevier B.V.
Comparative structural analysis of two proteins belonging to quorum sensing system in Vibrio cholerae
(2012) Mobashar Hussain; Turabe Fazil; Sunil Kumar; Naidu Subba Rao; Chandrabose Selvaraj; Sanjeev Kumar Singh; Haushila Prasad Pandey; Durg Vijai Singh
Vibrio cholerae uses quorum sensing communication system to interact with other bacteria and for gauzing environmental parameters. This organism dwells equally well in both human host and aquatic environments. Quorum sensing regulates multitude of activities and is one of the lucrative targets presently pursued for drug design in bacteria to encounter virulence. Histidine phosphotransfer protein LuxU and response regulator LuxO of V. cholerae are known to play important roles in biofilms and virulence machinery. In the present study, we used computational methods to model LuxU and LuxO and simulated the interactions of LuxO and LuxU. Since no structural details of the proteins were available, we employed homology modeling to construct the three-dimensional structures and then performed molecular dynamics simulations to study dynamic behavior of the LuxO and LuxU from V. cholerae. The modeled proteins were validated and subjected to molecular docking analyses. This allowed us to predict the binding modes of the proteins to elucidate probable sites of interference. © 2012 Taylor & Francis.
Hermite–Hadamard-type inequalities for interval-valued preinvex functions via Riemann–Liouville fractional integrals
(Springer Science and Business Media Deutschland GmbH, 2021) Nidhi Sharma; Sanjeev Kumar Singh; Shashi Kant Mishra; Abdelouahed Hamdi
In this paper, we introduce (h1, h2) -preinvex interval-valued function and establish the Hermite–Hadamard inequality for preinvex interval-valued functions by using interval-valued Riemann–Liouville fractional integrals. We obtain Hermite–Hadamard-type inequalities for the product of two interval-valued functions. Further, some examples are given to confirm our theoretical results. © 2021, The Author(s).
In vitro and in vivo evaluation of buccal bioadhesive films containing salbutamol sulphate
(2010) Sanjay Singh; Rajeev Soni; Manoj Kumar Rawat; Achint Jain; Shripad Bheemrao Deshpande; Sanjeev Kumar Singh; Madaswamy Sona Muthu
The aim of present study was to prepare and evaluate buccal bioadhesive films of salbutamol sulphate (SS) for the treatment of asthma. The films were designed to release the drug for a prolonged period of time so as to reduce the frequency of administration of the available conventional dosage forms of SS. The different proportions of sodium carboxymethylcellulose (SCMC) and Carbopol 940P (CP 940P) were used for the preparation of films. Carbopol was used to incorporate the desired bioadhesiveness in the films. The films were prepared by solvent casting method and evaluated for bioadhesion, in vitro drug release and anti asthmatic effect (bronchoprotection) in histamine induced bronchospasm of guinea pigs. In vitro drug release from the film was determined using a modified Franz diffusion cell while bioadhesiveness was evaluated with a modified two-arm balance using guinea pig buccal mucosa as a model tissue. Films containing SCMC : CP 940P ratio of 76 : 24 was found to be the best with moderate swelling along with favorable bioadhesion force and in vitro drug release. The drug release mechanism was found to follow non-Fickian diffusion as release mechanism. The prolonged in vivo effect (bronchoprotection) obtained from the buccal bioadhesive film of SS administered via buccal route may improve the treatment of asthmatic disorders by reducing the frequency of administration which is associated with the tolerance effect of SS. Additionally for the clinical benefit, it is also expected to reduce the major adverse effects of SS such as tachycardia and arrhythmias via buccal absorption. © 2010 Pharmaceutical Society of Japan.
Multiobjective convex optimization in real banach space
(MDPI, 2021) Kin Keung Lai; Mohd Hassan; Jitendra Kumar Maurya; Sanjeev Kumar Singh; Shashi Kant Mishra
In this paper, we consider convex multiobjective optimization problems with equality and inequality constraints in real Banach space. We establish saddle point necessary and sufficient Pareto optimality conditions for considered problems under some constraint qualifications. These results are motivated by the symmetric results obtained in the recent article by Cobos Sánchez et al. in 2021 on Pareto optimality for multiobjective optimization problems of continuous linear operators. The discussions in this paper are also related to second order symmetric duality for nonlinear multiobjective mixed integer programs for arbitrary cones due to Mishra and Wang in 2005. Further, we establish Karush–Kuhn– Tucker optimality conditions using saddle point optimality conditions for the differentiable cases and present some examples to illustrate our results. The study in this article can also be seen and extended as symmetric results of necessary and sufficient optimality conditions for vector equilibrium problems on Hadamard manifolds by Ruiz-Garzón et al. in 2019. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.
On characterizations of solution sets of interval-valued quasiconvex programming problems
(EDP Sciences, 2023) Shashi Kant Mishra; Sanjeev Kumar Singh; Mohd Hassan
In this article, we study several characterizations of solution sets of LU-quasiconvex interval-valued function. Firstly, we provide Gordan's theorem of the alternative of interval-valued linear system. As a consequence of this theorem, we find the normalized gradient of the interval-valued function is constant over the solution set when its gradient is not zero. Further, we discuss Lagrange multiplier characterizations of solution sets of LU-quasiconvex interval-valued function and provide optimality conditions of interval-valued optimization problem under the generalized Mangasarian-Fromovitz constraint qualifications. We provide illustrative examples in the support of our theory. © 2023 The authors. Published by EDP Sciences, ROADEF, SMAI.
On Monotone Maps: Semidifferentiable Case
(Springer Verlag, 2020) Shashi Kant Mishra; Sanjeev Kumar Singh; Avanish Shahi
In this paper, we define the concepts of monotonicity and generalized monotonicity for semidifferentiable maps. Further, we present the characterizations of convexity and generalized convexity in case of semidifferentiable functions. These results rely on general mean-value theorem for semidifferentiable functions (J Glob Optim 40:503–508, 2010). © 2020, Springer Nature Switzerland AG.
On strong pseudomonotone and strong quasimonotone maps
(Springer New York LLC, 2018) Sanjeev Kumar Singh; Avanish Shahi; S.K. Mishra
We introduce strong pseudomonotone and strong quasimonotone maps of higher order and establish their relationships with strong pseudoconvexity and strong quasiconvexity of higher order, respectively, which yields first-order characterizations of strong pseudoconvex and strong quasiconvex functions of higher order. Moreover, we answer the open problem (converse part of Proposition 6.2) of Karamardian and Schaible (J. Optim. Theory Appl. 66:37–46,1990), for even more generalized functions, namely strongly pseudoconvex functions of higher order. © Springer Nature Singapore Pte Ltd. 2018.
On strong variational inequalities in banach space
(International Publications, 2021) Mohd Hassan; Sanjeev Kumar Singh; S.K. Mishra
In this paper, we introduce strong variational inequality problem for real smooth Banach space. This paper deals with the existence and uniqueness results for the strong variational inequality problems under strongly accretive mappings. © 2021, International Publications. All rights reserved.
Semidefinite Multiobjective Mathematical Programming Problems with Vanishing Constraints Using Convexificators
(MDPI, 2022) Kin Keung Lai; Mohd Hassan; Sanjeev Kumar Singh; Jitendra Kumar Maurya; Shashi Kant Mishra
In this paper, we establish Fritz John stationary conditions for nonsmooth, nonlinear, semidefinite, multiobjective programs with vanishing constraints in terms of convexificator and introduce generalized Cottle type and generalized Guignard type constraints qualification to achieve strong S−stationary conditions from Fritz John stationary conditions. Further, we establish strong S−stationary necessary and sufficient conditions, independently from Fritz John conditions. The optimality results for multiobjective semidefinite optimization problem in this paper is related to two recent articles by Treanta in 2021. Treanta in 2021 discussed duality theorems for special class of quasiinvex multiobjective optimization problems for interval-valued components. The study in our article can also be seen and extended for the interval-valued optimization motivated by Treanta (2021). Some examples are provided to validate our established results. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.
Stationary Conditions and Characterizations of Solution Sets for Interval-Valued Tightened Nonlinear Problems
(MDPI, 2022) Kin Keung Lai; Shashi Kant Mishra; Sanjeev Kumar Singh; Mohd Hassan
In this paper, we obtain characterizations of solution sets of the interval-valued mathematical programming problems with switching constraints. Stationary conditions which are weaker than the standard Karush–Kuhn–Tucker conditions need to be discussed in order to find the necessary optimality conditions. We introduce corresponding weak, Mordukhovich, and strong stationary conditions for the corresponding interval-valued mathematical programming problems with switching constraints (IVPSC) and interval-valued tightened nonlinear problems (IVTNP), because the W-stationary condition of IVPSC is equivalent to Karush–Kuhn–Tucker conditions of the IVTNP. Furthermore, we use strong stationary conditions to characterize the several solutions sets for IVTNP, in which the last ones are particular solutions sets for IVPSC at the same time, because the feasible set of tightened nonlinear problems (IVTNP) is a subset of the feasible set of the mathematical programs with switching constraints (IVPSC). © 2022 by the authors.
Strong Pseudoconvexity and Strong Quasiconvexity of Non-differentiable Functions
(Springer Science and Business Media Deutschland GmbH, 2021) Sanjeev Kumar Singh; Avanish Shahi; Shashi Kant Mishra
In this chapter, we introduce the concept of strong pseudomonotonicity and strong quasimonotonicity of set-valued maps of higher order. Non-differentiable strong pseudoconvex/quasiconvex functions of higher order are characterized by the strong pseudomonotonicity/quasimonotonicity of their corresponding set-valued maps. As a by-product, we solve the open problem (converse part of Proposition 6.2) of Karamardian and Schaible (J. Optim. Theory Appl. 66:37–46, 1990) for the more general case as strong pseudoconvexity for non-smooth, locally Lipschitz continuous functions. © 2021, Springer Nature Switzerland AG.
Targeting COVID-19 (SARS-CoV-2) main protease through active phytochemicals of ayurvedic medicinal plants–Withania somnifera (Ashwagandha), Tinospora cordifolia (Giloy) and Ocimum sanctum (Tulsi)–a molecular docking study
(Taylor and Francis Ltd., 2022) Priya Shree; Priyanka Mishra; Chandrabose Selvaraj; Sanjeev Kumar Singh; Radha Chaube; Neha Garg; Yamini Bhusan Tripathi
COVID-19 (Coronavirus disease 2019) is a transmissible disease initiated and propagated through a new virus strain SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus-2) since 31st December 2019 in Wuhan city of China and the infection has outspread globally influencing millions of people. Here, an attempt was made to recognize natural phytochemicals from medicinal plants, in order to reutilize them against COVID-19 by the virtue of molecular docking and molecular dynamics (MD) simulation study. Molecular docking study showed six probable inhibitors against SARS-CoV-2 Mpro (Main protease), two from Withania somnifera (Ashwagandha) (Withanoside V [10.32 kcal/mol] and Somniferine [9.62 kcal/mol]), one from Tinospora cordifolia (Giloy) (Tinocordiside [8.10 kcal/mol]) and three from Ocimum sanctum (Tulsi) (Vicenin [8.97 kcal/mol], Isorientin 4′-O-glucoside 2″-O-p-hydroxybenzoagte [8.55 kcal/mol] and Ursolic acid [8.52 kcal/mol]). ADMET profile prediction showed that the best docked phytochemicals from present work were safe and possesses drug-like properties. Further MD simulation study was performed to assess the constancy of docked complexes and found stable. Hence from present study it could be suggested that active phytochemicals from medicinal plants could potentially inhibit Mpro of SARS-CoV-2 and further equip the management strategy against COVID-19-a global contagion. Highlights Holistic approach of Ayurvedic medicinal plants to avenge against COVID-19 pandemic. Active phytoconstituents of Ayurvedic medicinal plants Withania somnifera (Ashwagandha), Tinospora cordifolia (Giloy) and Ocimum sanctum (Tulsi) predicted to significantly hinder main protease (Mpro or 3Clpro) of SARS-CoV-2. Through molecular docking and molecular dynamic simulation study, Withanoside V, Somniferine, Tinocordiside, Vicenin, Ursolic acid and Isorientin 4′-O-glucoside 2″-O-p-hydroxybenzoagte were anticipated to impede the activity of SARS-CoV-2 Mpro. Drug-likeness and ADMET profile prediction of best docked compounds from present study were predicted to be safe, drug-like compounds with no toxicity. Communicated by Ramaswamy H. Sarma. © 2020 Informa UK Limited, trading as Taylor & Francis Group.