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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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麦蒂森论语域

中国外语 2023年第5期20卷 37-46页

作者：王博 Christian m.i.m.matthiessen 马园艺澳门大学中国澳门湖南大学马德里康普顿斯大学广东科学技术职业学院

Christian ***是系统功能语言学领域的领军学者之一,他在语域研究方面有着较多的重要成果。本文总结了matthiessen关于语域的观点,讨论了如何以三维视角考察语域,阐释了语域变异同方言变异和语码变异的区别,并且从实例化和层次化的角度... 详细信息

Christian ***是系统功能语言学领域的领军学者之一,他在语域研究方面有着较多的重要成果。本文总结了matthiessen关于语域的观点,讨论了如何以三维视角考察语域,阐释了语域变异同方言变异和语码变异的区别,并且从实例化和层次化的角度对语域概念进行了解读。此外,本文将系统功能语言学的语域研究置于整个语言学的框架中考察,加强了系统功能语言学的语域研究同其他学派研究之间的联系。

关键词：语域系统功能语言学语域变异语域绘图学活动语场

magnetic properties of Sn-substituted Ni-Zn ferrites synthesized from nano-sized powders of NiO, ZnO, Fe2O3, and SnO2

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Chinese Physics B 2017年第7期26卷 377-382页

作者： m A Ali m m Uddin m N i Khan F U Z Chowdhury S m Hoque S i Liba Department of Physics Chittagong University of Engineering and Technology (CUET) materials Science Division Atomic Energy Center

A series of Ni0.6-x/2Zn0.4-x/2SnxFe2O4(x = 0.0, 0.05, 0.1, 0.15, 0.2, and 0.3)(NZSFO) ferrite composities have been synthesized from nano powders using a standard solid state reaction technique. The spinel cubic structure of the investigated samples has been confirmed by x-ray diffraction(XRD). The magnetic properties such as saturation magnetization(ms),remanent magnetization(mr), coercive field(Hc), and Bohr magneton(μ) are calculated from the hysteresis loops. The value of m.is found to decrease with increasing Sn content in the samples. This change is successfully explained by the variation of A-B interaction strength due to Sn substitution in different sites. The compositional stability and quality of the prepared ferrite composites have also been endorsed by the fairly constant initial permeability(μ’) over a wide range of frequency. The decreasing trend of μ’ with increasing Sn content has been observed. Curie temperature TChas been found to increase with the increase in Sn content. A wide spread frequency utility zone indicates that the NZSFO can be considered as a good candidate for use in broadband pulse transformers and wide band read-write heads for video recording. The composition of x = 0.05 shows unusual results and the possible reason is also mentioned with the established formalism.

关键词： magnetic properties saturation magnetization permeability Curie temperature

miNimUm CONGESTiON SPANNiNG TREES iN BiPARTiTE AND RANDOm GRAPHS

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Acta mathematica Scientia 2011年第2期31卷 634-640页

作者： m.i. Ostrovskii Department of mathematics and Computer Science St. John's University

The first problem considered in this article reads： is it possible to find upper estimates for the spanning tree congestion in bipartite graphs, which are better than those for general graphs？ it is proved that there exists a bipartite version of the known graph with spanning tree congestion of order n3/2, where n is the number of vertices. The second problem.is to estimate spanning tree congestion of random graphs. it is proved that the standard model of random graphs cannot be used to find graphs whose spanning tree congestion has order greater than n3/2.

关键词： Bipartite graph random graph minimum congestion spanning tree

Collapse period of degrading SDOF systems

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Earthquake Engineering and Engineering Vibration 2014年第4期13卷 681-694页

作者： Borekci m Kircil mS Ekiz i Yildiz Technical University

Seismic demand estimation for a structure is a critical issue for seismic performance assessment so that the potential damage can be estimated realistically. many researchers proposed simplified methods to estimate the demand of a structure under strong ground motions. However, most of them did not consider degradation and collapse potential of the structures. Even some of theme considered the degradation effect, stiffness and strength degradation effects were considered separately without collapse potential caused by dynamic instability. in this study, collapse potential of SDOF systems caused by dynamic instability with stiffness and strength degradation has been investigated. Nonlinear time history analyses were performed, using an energy-based, strength and stiffness degraded hysteretic model that considers the collapse potential, with 160 earthquake acceleration time histories. An equation was proposed for the estimation of collapse period of SDOF systems as a function of certain strength reduction factor, ductility level and post-capping stiffness ratio. Finally, effects of parameters of the considered hysteretic model and local site conditions on the collapse period were investigated.

关键词： collapse degradation dynamic instability hysteretic types,earthquake

Electron transport in electrically biased inverse parabolic double-barrier structure

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Chinese Physics B 2016年第5期25卷 326-332页

作者： m Bati S Sakiroglu i Sokmen Physics Department Faculty of Science Dokuz Eylül University Physics Department Graduate School of Natural and Applied Sciences Dokuz Eylül University Physics Department Faculty of Arts and Sciences Recep Tayyip Erdogan University

A theoretical study of resonant tunneling is carried out for an inverse parabolic double-barrier structure subjected to an external electric field. Tunneling transmission coefficient and density of states are analyzed by using the non-equilibrium Green＇s function approach based on the finite difference method. it is found that the resonant peak of the transmission coefficient, being unity for a symmetrical case, reduces under the applied electric field and depends strongly on the variation of the structure parameters.

关键词： inverse parabolic double-barrier structure resonant tunneling non-equilibrium Green's function electric field

Sleep as a window to understand and regulate Alzheimer's disease:emerging roles of thalamic reticular nucleus

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Neural Regeneration Research 2025年第6期20卷 1711-1712页

作者： Haoqi Sun Shiqian Shen Robert J.Thomas m.Brandon Westover Can Zhang Department of Neurology Beth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMAUSA Center for Translational Pain Research Department of AnesthesiaCritical Care and Pain MedicineMassachusetis General HospitalHarvard Medical SchoolBostonMAUSA Division of Pulmonary Critical Care and Sleep MedicineDepartment of MedicineBeth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMAUSA Genetics and Aging Research Unit McCance Center for Brain HealthMass General Institute for Neurodegenerative DiseaseDepartment of NeurologyMassachusetts General HospitalHarvard Medical SchoolBostonMAUSA

introduction:Alzheimer 's disease(AD) is a common neurodegenerative disorder and the primary cause of dementia. Considerable evidence supports the “amyloid hypothesis,” stating that the pathogenesis of AD is primarily caused by the deposition of amyloid-β(Aβ), which drives tau phosphorylation, neuroinflammation, and neurodegeneration in the brain. The amyloid hypothesis is strengthened by the significant and moderate benefit of lecanemab, a humanized antibody through an anti-amyloid mechanism,showing slowed clinical decline(van Dyck et al.,2023). The recent positive results of anti-amyloid trials have brought back focus on the amyloid hypothesis through biochemical, genetic, and pharmacological approaches(Zhang, 2023).

关键词： Alzheimer inflammation hypothesis

Enhancement of coercivity,permeability,and dielectric properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ferrites for memory and high frequency devices

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Journal of Rare Earths 2024年第6期42卷 1128-1135,I0005页

作者： i.Sardar m.D.Hossain m.S.Sikder m.N.i.Khan m.R.Rahman Physics Discipline Khulna UniversityKhulna9208Bangladesh Department of Physics Khulna University of Engineering&TechnologyKhulna9203Bangladesh Department ofComputer Science and Engineering Northern University of Business&Technology KhulnaKhulna9100Bangladesh material Science Division Atomic Energy CentreDhaka1000Bangladesh

Spinel cubic ferrites have huge applications in me mory and high frequency *** the improvement of these modern devices,the magnetic coercivity,permeability,and dielectric properties of a ferrite are the important *** article focuses on improving the magnetic coercivity,magnetic permeability,and dielectric properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ferrites,where x=0.00,0.06,and *** X-ray diffraction(XRD),Fourier transform.infrared spectroscopy(FTiR),field emission scanning electron microscopy(FESEm),energy dispersive X-ray(EDX),vibrating sample magnetometer(VSm),and an impedance analyzer were used to characterize the structural,magnetic,and dielectric properties of the *** XRD patterns indicate the formation of spinel cubic structure of the samples with a secondary peak(EuFeO_(3))for Eu doped *** densities and porosities of the samples follow an inverse trend,where the doped samples’lattice parameters are increased with the increment of rare earth Eu *** FTiR analysis also proves the spinel cubic phase of the *** average grain size of the ferrites is obtained via FESEm.images,and it is increased from 121 to 198 *** analysis confirms that doping of the Eu content also changes other hysteresis loop properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ***,the coercivity of the Eu doped samples is greater than that of the mother alloy(x=0.00).The EDX study shows that there is no impurity contamination in the *** permeability and dielectric measurements show an improved quality factor of the Eu-doped samples with low magnetic and dielectric *** dependent resistivity and impedance analysis also show the improved *** the observed properties of the samples,all the investigated ferrites might be strong candidates for potential applications in memory devices,magnetic sensors,and high frequency applications.

关键词： Ferrites Raree arths Coercivity Permeability EDX Resistivity

Experimental nuclear charge density and theoretical description of theabove-barrier light heavy-ion fusion process

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Chinese Physics C 2023年第8期47卷 64-74页

作者： i.i.Gontchar m.V.Chushnyakova Physics and Chemistry Department Omsk State Transport UniversityOmskRussia Physics Department Omsk State Technical UniversityOmskRussia

Theoretical modeling of nucleus-nucleus collisions is often based on the nucleus-nucleus *** of the advanced methods for constructing this potential is the semi-microscopical double-folding model with m3 YParis *** and neutron densities are significant components of this *** correct nucleon density(ND) must reproduce the experimental nuclear charge density(NCD).However,those who deal with modeling the fusion process typically disregard this *** aim to achieve a good description of both the nuclear charge density and above-barrier fusion cross sections of even-even light nuclei with Z=*** consider several versions of NDs available in literature and construct our own approximation for the ND of the even-even spherical nuclei^(12)C,^(16)O,and^(40)Ca,abbreviated as FE-density(Fermi+exponential).We carefully compare the NCDs resulting from different versions of NDs with the experimental *** finding the nucleus-nucleus potential using the double-folding model with the density dependent m3 Y-Paris NN-forces and FE densities,we evaluate the abovebarrier fusion cross sections for five reactions,^(12)C+^(12)C,^(12)C+^(16)O,^(16)O+^(16)O,^(16)O+^(40)Ca,and^(40)Ca+^(40)Ca,and40Ca+40Ca,for which experimental data are *** cross sections are calculated using two approaches:a) the barrier penetration model and b) the trajectory model with surface friction(Tm).To find the transmission coefficients for the Tm,the Langevin equations are *** all considered reactions,our Tm typically reproduces the above-barrier experimental cross sections within 10-15%.The only adjustable parameter of the model,the optimal friction strength KRm.is found to be approximately 90 zs·GeV-1for the light reactions12C+12C,12C+16O,and16O+16O and approximately 15zs·GeV-1for the heavy reactions16O+40Ca and40Ca+*** latter findings are in reasonable agreement with the systematics found ***,the FE-recipe allows highly accurate and s

关键词： nuclear charge densities nucleon densities heavy-ion fusion surface friction double-fold-ing model