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GENERALIZEd FRACTIONAL CALCULUS OF THE ALEPH-FUNCTION INVOLVING A GENERAL CLASS OF POLYNOMIALS

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Acta Mathematica Scientia 2015年第5期35卷 1095-1110页

作者： R.K.SAXENA d.kumar department of Mathematics and Statistics Jai Narain Vyas University

The object of this article is to study and develop the generalized fractional calcu- lus operators given by Saigo and Maeda in 1996. We establish generalized fractional calculus formulas involving the product of R-function, Appell function F3 and a general class of poly- nomials. The results obtained provide unification and extension of the results given by Saxena et al. [13], Srivastava and Grag [17], Srivastava et al. [20], and etc. The results are obtained in compact form and are useful in preparing some tables of operators of fractional calculus. On account of the general nature of the Saigo-Maeda operators, R-function, and a general class of polynomials a large number of new and known results involving Saigo fractional calculus operators and several special functions notably H-function, /-function, Mittag-Leffier function, generalized Wright hypergeometric function, generalized Bessel-Maitland function follow as special cases of our main findings.

关键词： generalized fractional calculus operators a general class of polynomials R-function H-function /-function generalized Wright hypergeometric function Mittag-Leffler function generalized Bessel-Maitland function

Constructing a biofunctionalized 3d-printed gelatin/sodium alginate/chitosan tri-polymer complex scaffold with improvised biological andmechanical properties for bone-tissue engineering

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Bio-design and Manufacturing 2024年第1期7卷 57-73页

作者： Amit kumar Singh krishna Pramanik Amit Biswas Centre of Excellence in Tissue Engineering Department of Biotechnology and Medical EngineeringNational Institute of TechnologyRourkela 769008India

Sodium alginate(SA)/chitosan(CH)polyelectrolyte scaffold is a suitable substrate for tissue-engineering *** present study deals with further improvement in the tensile strength and biological properties of this type of scaffold to make it a potential template for bone-tissue *** experimented with adding 0%–15%(volume fraction)gelatin(GE),a protein-based biopolymer known to promote cell adhesion,proliferation,and *** resulting tri-polymer complex was used as bioink to fabricate SA/CH/GEmatrices by three-dimensional(3d)*** studies using scanning electron microscopy revealed the microfibrous porous architecture of all the structures,which had a pore size range of 383–419μm.X-ray diffraction and Fourier-transform infrared spectroscopy analyses revealed the amorphous nature of the scaffold and the strong electrostatic interactions among the functional groups of the polymers,thereby forming polyelectrolyte complexes which were found to improve mechanical properties and structural *** scaffolds exhibited a desirable degradation rate,controlled swelling,and hydrophilic characteristics which are favorable for bone-tissue *** tensile strength improved from(386±15)to(693±15)kPa due to the increased stiffness of SA/CH scaffolds upon addition of *** enhanced protein adsorption and in vitro bioactivity(forming an apatite layer)confirmed the ability of the SA/CH/GE scaffold to offer higher cellular adhesion and a bone-like environment to cells during the process of tissue *** vitro biological evaluation including the MTT assay,confocal microscopy analysis,and alizarin red S assay showed a significant increase in cell attachment,cell viability,and cell proliferation,which further improved biomineralization over the scaffold *** addition,SA/CH containing 15%gelatin designated as SA/CH/GE15 showed superior performance to the other fabricated 3d structures,demonstrating its pote

关键词： Scaffold Biomaterial Sodium alginate Chitosan Gelatin 3d printing Tissue engineering

Translocator protein and neurodegeneration: insights from Alzheimer’s disease

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Neural Regeneration Research 2025年第4期20卷 1090-1091页

作者： Arpit kumar Pradhan Rainer Rupprecht Gerhard Rammes Klinik für Anaesthesiologie und Intensivmedizin der Technischen Universität München Klinikum rechts der IsarMunichGermany Graduate School of Systemic Neurosciences Ludwig-Maximilians-Universität MünchenMartinsriedGermany department of Psychiatry and Psychotherapy University RegensburgRegensburgGermany

The 18 kda translocator protein(TSPO)located on the outer mitochondrial membrane regulates several key cellular processes including mitochondrial homeostasis,cholesterol transport,apoptosis,cell proliferation,and maintenance of mitochondrial health(Rupprecht et al.,2022,2023).TSPO is expressed in both peripheral organs and the central nervous system,with a more pronounced expression in tissues that produce *** main reason why TSPO has garnered so much attention is because it plays a key role in neurosteroidogenesis by transferring cholesterol from the outer to the inner mitochondrial membrane,which is the rate-limiting step in neurosteroid synthesis.A cholesterol-recognizing amino acid consensus domain has been identified in the cytosolic C terminus of the TSPO protein by both in vitro and site-directed mutagenesis experiments(Li et al.,2001).However,the role of TSPO in the process of neurosteroid synthesis has been challenged by several studies,particularly TSPO knockout models,which suggest that TSPO removal does not affect the phenotype or the system’s viability(Tu et al.,2014).However,ligands targeting TSPO have been shown to enhance levels of neurosteroids which suggests that neurosteroidogenesis is one of the major functional roles mediated by the TSPO protein.

关键词： cholesterol organs

Mechanical and Corrosion Properties of Magnesiume-Hydroxyapatite (MgeHA) Composite Thin Films

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Journal of Materials Science & Technology 2013年第9期29卷 788-794页

作者： K.Mensah-darkwa R.K.Gupta d.kumar Engineering Research Center of Revolutionizing Metallic Biomaterials Department of Mechanical Engineering North Carolina A & T State University department of Chemistry Pittsburg State University

Magnesium(Mg)-hydroxyapatite(Ca10(PO4)6(OH)2,abbreviated as HA) composite films have been grown on Mg plates using a pulsed laser deposition *** property measurements and analysis have indicated that hardness and Young’s modulus of nMge(100e n)HA composite coatings increase with Mg content in the coatings and reach a maximum at a 70Mge 30HA composition.n and 100e n in the nMge(100e n)HA represent the relative number of laser pulses impinging on Mg and HA targets,*** current potentiodynamic polarization studies have shown that the corrosion of Mg plate(control) decreases with an increase in the HA ratio in the composite *** example,the corrosion current density of Mg plate reduces by w350 times after coating the Mg plate with 10Mge 90HA composite *** reduction in corrosion current density of Mg plates was also accompanied by a positive shift in the corrosion potential(w6%) due to this *** mechanism behind the reduction in corrosion behavior of Mg plates due to nMge(100e n) HA composite coatings has been understood by electrochemical impedance spectroscopy.

关键词： Magnesium Hydroxyapatite Scanning electron microscopy Pulsed laser deposition Corrosion Impedance spectroscopy

A threshold voltage model of short-channel fully-depleted recessed-source/drain(Re-S/d) SOI MOSFETs with high-k dielectric

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Chinese Physics B 2015年第10期24卷 604-611页

作者： Gopi krishna Saramekala Sarvesh dubey Pramod.kumar Tiwari department of Electronics and Communication Engineering National Institute of Technology Shri Ramswaroop Memorial University

In this paper, a surface potential based threshold voltage model of fully-depleted（Fd） recessed-source/drain（Re-S/d）silicon-on-insulator（SOI） metal-oxide semiconductor field-effect transistor（MOSFET） is presented while considering the effects of high-k gate-dielectric material induced fringing-field. The two-dimensional（2d） Poisson＇s equation is solved in a channel region in order to obtain the surface potential under the assumption of the parabolic potential profile in the transverse direction of the channel with appropriate boundary conditions. The accuracy of the model is verified by comparing the model＇s results with the 2d simulation results from ATLAS over a wide range of channel lengths and other parameters,including the dielectric constant of gate-dielectric material.

关键词： recessed-source/drain (Re-S/d) high-k gate-material fringing field and SCEs

Corrosion Protective Conversion Coatings on Magnesium disks Using a Hydrothermal Technique

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Journal of Materials Science & Technology 2014年第1期30卷 47-53页

作者： R.K.Gupta K.Mensah-darkwa d.kumar department of Chemistry Pittsburg State University Engineering Research Center for Revolutionizing Metallic Biomaterials(ERC-RMB) Department of Mechanical EngineeringNorth Carolina A&T State University

A uniform, compact, and well adherent conversion coating of magnesium hydroxide has been formed on bioresorbable magnesium disks by means of a hydrothermal technique. Electrochemical results indicate that the coating brings about a significant reduction in magnesium corrosion in phosphate buffered saline （PBS） solution. It is also observed that corrosion resistance of the coating increases with an increase in treatment time, which in turn, increases the coating thickness. The protective behavior of magnesium hydroxide coating is attributed to its chemical inertness in PBS solution. The coatings are found to be free from pores that reduce the direct contact between corroding media and underlying magnesium.

关键词： Magnesium Polarization Electrochemical impedance spectroscopy (EIS) Scanning electron microscopy (SEM) Conversioncoating Corrosion

New Exact Traveling Wave Solutions of the Unstable Nonlinear Schrdinger Equations

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Communications in Theoretical Physics 2017年第12期67卷 761-767页

作者： K.Hosseini d.kumar M.Kaplan E.Yazdani Bejarbaneh department of Mathematics Rasht Branch Islamic Azad University Graduate School of Systems and Information Engineering University of Tsukuba department of Mathematics Bangabandhu Sheikh Mujibur Rahman Science and Technology University department of Mathematics Art-Science Faculty Kastamonu University Young Researchers and Elite Club Qazvin Branch Islamic Azad University

The present paper studies the unstable nonlinear Schr¨odinger equations, describing the time evolution of disturbances in marginally stable or unstable media. More precisely, the unstable nonlinear Schr¨odinger equation and its modified form are analytically solved using two efficient distinct techniques, known as the modified Kudraysov method and the sine-Gordon expansion approach. As a result, a wide range of new exact traveling wave solutions for the unstable nonlinear Schr¨odinger equation and its modified form are formally obtained.

关键词： unstable nonlinear SchrSdinger equation modified unstable nonlinear Schrodinger equation mod-ified Kudryashov method sine-Gordon expansion approach new exact traveling wave solutions

Computational Analysis of Surface Pressure distribution over a 2d Wedge in the Supersonic and Hypersonic Flow Regimes

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Fluid dynamics & Materials Processing 2023年第6期19卷 1637-1653页

作者： Javed S.Shaikh krishna kumar Khizar A.Pathan Sher A.Khan MIT School of Engineering MIT ADT UniversityPune412201India Trinity College of Engineering and Research Pune411048India department of Mechanical Engineering International Islamic University MalaysiaKuala Lumpur53100Malaysia

The complex fluid-dynamic instabilities and shock waves occurring along the surface of a two-dimensional wedge at high values of the Mach number are studied here through numerical solution of the governing ***,a regression model is implemented to determine the pressure distribution for various Mach numbers and angles of *** Mach number spans the interval from 1.5 to *** wedge angles(θ)are from 5°to 25°.The pressure ratio(P2/P1)is reported at various locations(x/L)along the 2d *** results of the numerical simulations are compared with the regression model showing good agreement.

关键词： CFd analysis supersonic wedge angle Mach number

Modeling and multi-response optimization of machining performance while turning hardened steel with self-propelled rotary tool

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Advances in Manufacturing 2015年第1期3卷 84-95页

作者： Thella Babu Rao A.Gopala krishna Ramesh kumar Katta Konjeti Rama krishna department of Mechanical Engineering GITAM UniversityHyderabad 502329Andhra PradeshIndia department of Mechanical Engineering University College of EngineeringJNTUKKakinada 533003Andhra PradeshIndia Productionisation & Technology Transfer Defence R&D LaboratoryKanchanbaghHyderabad 500058Andhra PradeshIndia

There are many advanced tooling approaches in metal cutting to enhance the cutting tool performance for machining hard-to-cut materials. The self propelled rotary tool （SPRT） is one of the novel approaches to improve the cutting tool performance by providing cutting edge in the form of a disk, which rotates about its principal axis and provides a rest period for the cutting edge to cool and allow engaging a fresh cutting edge with the work piece. This paper aimed to present the cutting performance of SPRT while turning hardened EN24 steel and optimize the machining conditions. Surface roughness （Ra） and metal removal rate （rMMR） are considered as machining perfor- mance parameters to evaluate, while the horizontal incli- nation angle of the SPRT, depth of cut, feed rate and spindle speed are considered as process variables. Initially, design of experiments （dOEs） is employed to minimize the number of experiments. For each set of chosen process variables, the machining experiments are conducted on computer numerical control （CNC） lathe to measure the machining responses. Then, the response surface method- ology （RSM） is used to establish quantitative relationships for the output responses in terms of the input variables. Analysis of variance （ANOVA） is used to check the adequacy of the model. The influence of input variables on the output responses is also determined. Consequently, these models are formulated as a multi-response optimi- zation problem to minimize the Ra and maximize the rMMR simultaneously. Non-dominated sorting genetic algorithm-II （NSGA-II） is used to derive the set of Pareto-optimal solutions. The optimal results obtained through the pro- posed methodology are also compared with the results of validation experimental runs and good correlation is found between them.

关键词： Self-propelled rotary turning ~ Empiricalmodeling ~ Response surface methodology (RSM) - Multi-objective formulation - Optimization - Non-dominatedsorting genetic algorithm-II (NSGA-II)