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constraining the variable generalized chaplygin gas model in matter creation cosmology

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communications in Theoretical physics 2024年第10期76卷 119-134页

作者： Yogesh Bhardwaj c p singh Department of Applied Mathematics Delhi Technological UniversityBawana RoadDelhi-110042India

We explore the variable generalized chaplygin gas(VGcG)model in the theory of matter creation cosmology within the framework of a spatially homogeneous and isotropic flat Friedmann—Lemai tre—Robertson—Walker *** creation cosmology is based on reinterpretation of the energy–momentum tensor in Einstein's field *** creation corresponds to an irreversible energy flow from the gravitational field to the created matter *** variable chaplygin gas(VcG)is also studied as a particular *** use the Markov chain Monte carlo method to constrain the free parameters of three models,namely,Lambda-cold-Dark matter(ΛcDM),VGcG and VcG models with and without matter creation from the latest observational data from baryon acoustic oscillations,cosmic chronometer,type Ia supernovae(pantheon)including gamma-ray bursts,quasars and the local measurement of H_(0) from R21 *** different combinations of dataset provide a fairly tight constraint on the parameters of theΛcDM,VGcG and VcG *** present values of various cosmological parameters are obtained,which are very close to theΛcDM ***,we perform stability analysis,Bayesian evidence analysis and information criteria analysis for these models through studying the sound speed,Bayes factor,and Akaike information criteria(AIc)and Bayesian information criteria(BIc)selection *** values of sound speed for VGcG and VcG models shows that both the models are *** to AIc,it is observed that VGcG and VcG models with matter creation are supported considerably less by current observations,while BIc shows that these models are not favoured by observational data.

关键词： cosmological model matter creation chaplygin gas model dark energy

Exploring the role of N-acetyltransferases in diseases:a focus on N-acetyltransferase 9 in neurodegeneration

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Neural Regeneration Research 2025年第10期20卷 2862-2871页

作者： prajakta Deshpande Anuradha Venkatakrishnan chimata Amit singh Department of Biology University of DaytonDaytonOHUSA premedical program University of DaytonDaytonOHUSA center for Tissue Regeneration and Engineering at Dayton(TREND) University of DaytonDaytonOHUSA Integrative Science and Engineering center University of DaytonDaytonOHUSA center for Genomic Advocacy(TcGA) Indiana State UniversityTerre HauteINUSA

Acetyltransferases,required to transfer an acetyl group on protein are highly conserved proteins that play a crucial role in development and *** acetylation is a common post-translational modification pivotal to basic cellular *** to 80%-90%of proteins are acetylated during translation,which is an irreversible process that affects protein structure,function,life,and *** this review,we have discussed the various N-acetyltransferases present in humans,their function,and how they might play a role in ***,we have focused on N-acetyltransferase 9 and its role in microtubule *** have shed light on how N-acetyltransferase 9 and acetylation of proteins can potentially play a role in neurodegenerative *** have specifically discussed the N-acetyltransferase 9-acetylation independent function and regulation of c-Jun N-terminal kinase signaling and microtubule stability during development and neurodegeneration.

关键词： acetyl-coenzyme A Alzheimer’s disease animal models cell death drosophila eye human disease c-Jun N-terminal kinase signaling N-Acetyltransferases N-acetyltransferase 9 neurodegeneration

A comprehensive investigation on nonlinear vibration and bending characteristics of bio-inspired helicoidal laminated composite structures

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 81-100页

作者： S.SAURABH R.KIRAN D.singh R.VAISH V.S.cHAUHAN School of Mechanical and Materials Engineering Indian Institute of Technology Mandi

Bio-inspired helicoidal composite laminates, inspired by the intricate helical structures found in nature, present a promising frontier for enhancing the mechanical properties of structural designs. Hence, this study provides a comprehensive investigation into the nonlinear free vibration and nonlinear bending behavior of bio-inspired composite plates. The inverse hyperbolic shear deformation theory(IHSDT) of plates is employed to characterize the displacement field, with the incorporation of Green-Lagrange nonlinearity. The problem is modeled using the c0finite element method(FEM), and an in-house code is developed in the MATLAB environment to solve it numerically. Various helicoidal layup configurations including helicoidal recursive(HR), helicoidal exponential(HE), helicoidal semi-circular(HS), linear helicoidal(LH), and Fibonacci helicoidal(FH)with different layup sequences and quasi-isotropic configurations are studied. The model is validated, and parametric studies are conducted. These studies investigate the effects of layup configurations, side-to-thickness ratio, modulus ratios, boundary conditions, and loading conditions at different load amplitudes on the nonlinear vibration and nonlinear bending behaviors of bio-inspired composite plates. The results show that the laminate sequence exerts a substantial impact on both nonlinear natural frequencies and nonlinear bending behaviors. Moreover, this influence varies across different side-to-thickness ratios and boundary conditions of the bio-inspired composite plate.

关键词： Inverse problems

Utilization of alkali-activated copper slag as binder in concrete

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Frontiers of Structural and civil Engineering 2021年第3期15卷 773-780页

作者： Jagmeet singh S p singh Department of civil Engineering Dr.B R Ambedkar National Institute of TechnologyJalandhar144011India

This study was focused on developing concrete using alkali-activated copper slag(AAcS)as a *** properties of alkali-activated copper slag concrete(AAcSc)were compared with portland cement concrete(pcc).Different AAcSc mixes were prepared with varying Na_(2)O dosage(6%and 8%of the binder by weight)and curing *** products in AAcSc were retrieved using Fourier-transform infrared spectroscopy(FTIR)and X-ray powder diffraction(XRD)*** test results indicate that the workability of AAcSc was lesser than that of *** AAcSc mix with 6%Na_(2)O dosage has exhibited similar mechanical properties as that of *** mechanical properties of AAcSc were higher than pcc when 8%of Na_(2)O dosage was *** curing was effective to upgrade the strength properties of AAcSc at an early age of curing,but at a later age mechanical properties of ambient cured and heat-cured AAcSc were *** hydration products of AAcSc were not identified in XRD patterns,whereas,in FTIR spectra of AAcSc some alkali-activated reaction products were *** AAcSc mixes were found to be more sustainable than *** has been concluded that AAcSc can be produced similarly to that of pcc and ambient curing is sufficient.

关键词： binder concrete mechanical properties mineralogy workability

Acquired sensorineural hearing loss,oxidative stress,and microRNAs

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Neural Regeneration Research 2025年第9期20卷 2513-2519页

作者： Desmond A.Nunez Ru c.Guo Division of Otolaryngology–Head&Neck Surgery Department of SurgeryFaculty of MedicineThe University of British ColumbiaVancouverBCCanada Division of Otolaryngology–Head&Neck Surgery Gordon&Leslie Diamond Health Care CentreVancouver General HospitalVancouverBCCanada Faculty of Medicine–The University of British columbia VancouverBCCanada

Hearing loss is the third leading cause of human ***-related hearing loss,one type of acquired sensorineural hearing loss,is largely responsible for this escalating global health ***-induced,ototoxic,and idiopathic sudden sensorineural are other less common types of acquired hearing *** etiology of these conditions is complex and multi-fa ctorial involving an interplay of genetic and environmental *** stress has recently been proposed as a likely linking cause in most types of acquired sensorineural hearing *** non-coding RNA sequences known as microRNAs(miRNAs)have increasingly been shown to play a role in cellular hypoxia and oxidative stress responses including promoting an apoptotic *** hair cell death is a central histopathological finding in sensorineural hearing *** these cells do not regenerate in humans,it underlies the irreversibility of human age-related hearing *** EMBASE,Ovid MEDLINE,Web of Science core collection,and *** databases over the period August 1,2018 to July 31,2023 were searched with"hearing loss,""hypoxamiRs,""hypoxia,""microRNAs,""ischemia,"and"oxidative stress"text words for English language primary study publications or registered clinical *** red clinical trials known to the senior author we re also assessed.A total of 222studies were thus *** excluding duplicates,editorials,retra ctions,secondary research studies,and non-English language articles,39 primary studies and clinical trials underwent full-text *** resulted in 11 animal,in vitro,and/or human subject journal articles and 8 registered clinical trial database entries which form the basis of this narrative *** miR-34a and miR-29b levels increase with age in *** miRNAs were demonstrated in human neuroblastoma and murine cochlear cell lines to target Sirtuin 1/peroxisome proliferato r-activated receptor gamma coactivator-1-alpha(SIRT1/p Gc-1α),SIRT

关键词： hearing loss hypoxia microRNAs oxidative stress sensorineural

Vascular plants distribution in relation to topography and environmental variables in alpine zone of Kedarnath Wild Life Sanctuary,West Himalaya

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Journal of Mountain Science 2018年第9期15卷 1936-1949页

作者： cHANDRA Sudeep singh Ankit singh c.p. NAUTIYAL M.c. RAWAT L.S. High Altitude plant physiology Research centre(HAppRc)H.N.B.Garhwal University Srinagar Garhwal-246174UttarakhandIndia Space Applications centre (Indian Space Research Organization)Ahmedabad 380015India Govind Ballabh pant National Institute of Himalayan Environment&Sustainable Development Garhwal Unit Srinagar Garhwal-246174UttarakhandIndia

The present study was carried out in Tungnath alpine meadows of Kedarnath Wild Life Sanctuary, Western Himalaya from subalpine to upper alpine zone. A total of four summits were selected along an altitudinal gradient and sampled for detailed vegetation analysis using multi summit approach as per Global observation research initiative in alpine environments(GLORIA). Species richness, diversity, and evenness among four summits as well as the interaction between environmental variables with plant communities were assessed. Monthly mean soil temperature was calculated using data retrieved from geo-precision temperature logger in order to identify the trend of soil temperature among different season and altitudinal gradient and its implications to plant communities. Soil samples were analyzed fromeach summit by collecting randomized composite soil samples. The indirect non-metric multidimensional scaling(NMDS) and direct canonical correspondence analysis(ccA) tools of ordination techniques to determine the linkage between plant species from various sample summits and biotic/abiotic environmental gradients were used in the present study. The results of the study demonstrated increase in species richness as soil temperature increases, the ecotone representing summits were found most warm summits followed by highest species richness. Annual soil temperature increased by 1.43°c at timberline ecotone. Whereas, at upper alpine zone the soil temperature increased by 0.810 c from year 2015 to 2016. S?rensen's similarity index was found to be increased between subalpine and upper alpine zone with increase in the presence of subalpine plant species at upper alpine zone. Both the ordination tools separate the subalpine summit and their respective vegetation from summits representingtimberline ecotone and upper alpine zone. Soil p H, altitude, soil cation exchange capacity were found as the key abiotic drivers for distribution of plant species.

关键词： GLORIA Non-metric multidimensionalscaling (NMDS) canonical correspondence analysis(ccA) Ecotone West Himalaya

Reflection of three-dimensional plane waves at the free surface of a rotating triclinic half-space under the context of generalized thermoelasticity

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Applied Mathematics and Mechanics(English Edition) 2021年第9期42卷 1363-1378页

作者： p.singh A.K.singh A.cHATTOpADHYAY Department of Mathematics and computing Indian Institute of Technology(ISM)Dhanbad-826004JharkhandIndia

The reflection of three-dimensional(3D) plane waves in a highly anisotropic(triclinic) medium under the context of generalized thermoelasticity is studied. The thermoelastic nature of the 3D plane waves in an anisotropic medium is investigated in the perspective of the three-phase-lag(TpL), dual-phase-lag(DpL), Green-Naghdi-III(GNIII), Lord-Shulman(LS), and classical coupled(cL) theories. The reflection coefficients and energy ratios for all the reflected waves are obtained in a mathematical form. The rotational effects on the reflection characteristics of the 3D waves are discussed under the context of generalized thermoelasticity. comparative analyses for the reflection coefficients of the waves among these generalized thermoelastic theories are performed. The energy ratios for each of the reflected waves establish the energy conservation law in the reflection phenomena of the plane waves. The highly anisotropic materials along with the rotation may have a significant role in the phenomenon of the reflection behavior of the 3D waves. Numerical computations are performed for the graphical representation of the study.

关键词： reflection energy ratio triclinic thermoelasticity rotation three-dimensional(3D)wave

Rayleigh-type wave propagation in incompressible visco-elastic media under initial stress

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Applied Mathematics and Mechanics(English Edition) 2018年第3期39卷 317-334页

作者： p.singh A.cHATTOpADHYAY A.K.singh Department of Applied Mathematics Indian Institute of Technology (ISM)

propagation of Rayleigh-type surface waves in an incompressible visco-elastic material over incompressible visco-elastic semi-infinite media under the effect of initial stresses is discussed. The dispersion equation is determined to study the effect of differ- ent types of parameters such as inhomogeneity, initial stress, wave number, phase velocity, damping factor, visco-elasticity, and incompressibility on the Rayleigh-type wave prop- agation. It is found that the affecting parameters have a significant effect on the wave propagation. cardano＇s and Ferrari＇s methods are deployed to estimate the roots of dif- ferential equations associated with layer and semi-infinite media. The MATHEMATIcA software is applied to explicate the effect of these parameters graphically.

关键词： Rayleigh-type wave inhomogeneity initial stress visco-elasticity incom-pressible

Julia sets of permutable Holomorphic maps Dedicated to professor Sheng GONG on the occasion of his 75th birthday

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Science china Mathematics 2006年第11期49卷 1715-1721页

作者： singh Anand p Department of Mathematics University of Jammu Jammu-180006India

Let f and g be two permutable transcendental holomorphic maps in the *** shall discuss the dynamical properties of f, g and f o g and prove, among other things, that if either f has no wandering domains or f is of bou... 详细信息

关键词： Julia set, Fatou set, permutable maps.