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Predicting maximum Lifespan Limits at mean menopausal Age

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Journal of mathematical Research with Applications 2025年第1期 133-142页

作者： m.sUmATHI s.ANTONY CARLA department of mathematics N.M.S.S.Vellaichamy Nadar College Research scholar (Part-time) Madurai Kamaraj University

The age at which a woman enters natural menopause has also been associated to death from any cause. menopause is a natural component of aging that happens between the ages of 45 and 55, with the average menopausal age being 51. Previous research has revealed the age at which women reach menopause, but there is no evidence to support the link between menopause and longevity. We made a study in assessing the limits of maximum lifespan at menopausal age in our previous article. In this paper, we aim to predict the maximum lifespan of women at mean menopausal age.

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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.

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Exact solutions of Nonlinear Evolution Equations in mathematical Physics Using the modified simple Equation method

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Chinese Physics Letters 2012年第6期29卷 1-4页

作者： E.m.E.zayed s.A.Hoda Ibrahim department of mathematics Faculty of ScienceZagazig UniversityP.O.Box 44519ZagazigEgypt

The modified simple equation method is employed to construct the exact solutions involving parameters of nonlinear evolution equations via the (1+1)-dimensional modified KdV equation,and the (1+1)-dimensional reaction-diffusion *** these parameters are taken to be special values,the solitary wave solutions are derived from the exact *** is shown that the proposed method provides a more powerful mathematical tool for solving nonlinear evolution equations in mathematical physics.

关键词： equation. exact equation

Exact solutions of Kolmogorov-Petrovskii-Piskunov Equation Using the modified simple Equation method

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Acta mathematicae Applicatae sinica 2014年第3期30卷 749-754页

作者： E.m.E.zayed s.A.Hoda Ibrahim mathematics department Faculty of ScienceZagazig University

The modified simple equation method is employed to find the exact solutions of the nonlinear Kolmogorov-Petrovskii-Piskunov （KPP） equation. When certain parameters of the equations are chosen to be special values, the solitary wave solutions are derived from the exact solutions. It is shown that the modified simple equation method provides an effective and powerful mathematical tool for solving nonlinear evolution equations in mathematical physics.

关键词： modified simple equation method Kolmogorov-Petrovskii-Piskunov equation exact solutions solitary wave solutions

Impact of Zika virus non-structural protein mutations on hippocampal damage

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Neural Regeneration Research 2025年第8期20卷 2307-2308页

作者： Larissa m.G.Cassiano Roney s.Coimbra Neurogenômica/Imunopatologia Instituto RenéRachouFiocruzBelo HorizonteBrazil departamento de Bioquímica e Imunologia Instituto de Ciências BiológicasUniversidade Federal de Minas GeraisBelo HorizonteBrazil

The Zika virus(ZIKV),a member of the Flaviviridae family,attracted worldwide attention for its connection to severe neurological effects,notably microcephaly in newborns,first reported during the 2015 epidemic in ***,its impact goes beyond fetal and neonatal abnormalities,also affecting the central nervous system(CNs)in both children and adults,leading to enduring cognitive and behavioral impairments.

关键词： damage fetal neonatal

The 3d Inverse Problem of the Wave Equation for a General multi-connected Vibrating membrane with a Finite Number of Piecewise smooth Boundary Conditions

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Acta mathematica sinica,English series 2005年第4期21卷 733-752页

作者： E.m.E.zayed mathematics department Faculty of ScienceZagazig UniversityZagazig.Egypt

The trace of the wave kernel μ（t） =∑ω=1^∞ exp（-itEω^1/2）, where {Eω}ω^∞=1 are the eigenvalues of the negative Laplacian -△↓2 = -∑k^3=1 （δ/δxk）^2 in the （x^1, x^2, x^3）-space, is studied for a variety of bounded domains, where -∞ 〈 t 〈 ∞ and i= √-1. The dependence of μ （t） on the connectivity of bounded domains and the dirichlet, Neumann and Robin boundary conditions are analyzed. Particular attention is given for a multi-connected vibrating membrane Ω in Ra surrounded by simply connected bounded domains Ω j with smooth bounding surfaces s j （j = 1,……, n）, where a finite number of piecewise smooth dirichlet, Neumann and Robin boundary conditions on the piecewise smooth components si^＊（i = 1 ＋ kj-1,……, kj） of the bounding surfaces s j are considered, such that s j = Ui-1＋kj-1^kj si^＊, where k0=0. The basic problem is to extract information on the geometry Ω by using the wave equation approach from a complete knowledge of its eigenvalues. some geometrical quantities of Ω （e.g. the volume, the surface area, the mean curvuture and the Gaussian curvature） are determined from the asymptotic expansion ofexpansion of μ（t） for small │t│.

关键词： Inverse problem Wave kernal Eigenvalues Greens function multi-connected vibrating membrane Negative Laplacian Heat kernel

INVERsE PROBLEms FOR A GENERAL mULTI-CONNECTEd BOUNdEd dRUm WITH APPLICATIONs IN PHYsICs

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Acta mathematica scientia 2003年第1期23卷 104-116页

作者： E.m.E.zayed mathematics department Faculty of Science Zagazig University Zagazig Egypt

This paper studies the influence of a finite container on an ideal *** trace of the heat kernel (t) =exp, where are the eigenvalues of the negative Laplacian -in Rn(n = 2 or 3), is studied for a general multi-connected bounded drum ft which is surrounded by simply connected bounded domains Ωi with smooth boundaries Ωi(i = 1,… ,m) where the dirichlet, Neumann and Robin boundary conditions on Ωi(i = 1,…,m) are considered. some geometrical properties of Ω are determined. The thermodynamic quantities for an ideal gas enclosed in Ω are examined by using the asymptotic expansions of (t) for short-time t. It is shown that the ideal gas can not feel the shape of its container Ω, although it can feel some geometrical properties of it.

关键词： Inverse problem heat kernel eigenvalues an ideal gas multi-connected bounded domain

Asymptotic Expansions of the Heat Kernel of the Laplacian for General Annular Bounded domains with Robin Boundary Conditions：Further Results

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Acta mathematica sinica,English series 2003年第4期19卷 679-694页

作者： E.m.E.zayed departmentofmathematics FacultyofScienceZagazigUniversityZagazigEgypt

The asymptotic expansions of the trace of the heat kernel Θ(t) = Σ_(v =1)~∞exp(-tλ_v) for small positive t, where {λ_v} are the eigenvalues of the negative Laplacian-△_n = -Σ_(i = 1)~n(partial deriv/(partial deriv)x^i)~2 in R^n (n = 2 or 3), are studied for ageneral annular bounded domain Ω with a smooth inner boundary (partial deriv)Ω_1 and a smoothouter boundary (partial deriv)Ω_2, where a finite number of piecewise smooth Robin boundaryconditions (partial deriv/(partial deriv)n_j + γ_j)φ = 0 on the components Γ_j(j = 1, …, k) of(partial deriv)Ω_1 and on the components Γ_j(j = k + 1, …, m) of (partial deriv)Ω_2 areconsidered such that (partial deriv)Ω_1 = ∪_(j = 1)~kΓ_j and (partial deriv)Ω_2 = ∪_(j = k +1)~mΓ_j and where the coefficients γ_j(j = 1, …, m) are piecewise smooth positive functions. someapplications of Θ(t) for an ideal gas enclosed in the general annular bounded domain Ω are *** results are also obtained.

关键词： inverse problem heat kernel eigenvalues Robin boundary conditions classical ideal gas

The Asymptotics of the Two-dimensional Wave Equation for a General multi-Connected Vibrating membrane with Piecewise smooth Robin Boundary Conditions

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Acta mathematica sinica,English series 2004年第2期20卷 209-222页

作者： E.m.E.zayed department of mathematics Faculty of ScienceZagazig UniversityZagazigEgypt

The asymptotic expansion for small |t| of the trace of the wave kernel , where and are the eigenvalues of the negative Laplacian in the (x 2,x 2)-plane, is studied for a multi-connected vibrating membrane ? in R 2 surrounded by simply connected bounded domains ? j with smooth boundaries ?? j (j = 1, ..., n), where a finite number of piecewise smooth Robin boundary conditions on the piecewise smooth components Γ i (i = 1+k j?1, ..., k j ) of the boundaries ?? j are considered, such that and k 0 = 0. The basic problem is to extract information on the geometry of ? using the wave equation approach. some geometric quantities of ? (e. g. the area of ?, the total lengths of its boundary, the curvature of its boundary, the number of the holes of ?, etc.) are determined from the asymptotic expansion of the trace of the wave kernel for small |t|.

关键词： Inverse problem Wave kernel Eigenvalues Robin boundary conditions Vibrating membrane Hearing the shape of a drum