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uniform and L-convergence of Logarithmic Means of Walsh-Fourier series

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Acta Mathematica sinica,English series 2006年第2期22卷 497-506页

作者： G.Gát u.GOGINAVA Institute of Mathematics and Computer science College of Nyiregyhaza Department of Mechanics and Mathematics Tbilisi State University

the （Nsrlund） logarithmic means of the Fourier series of the integrable function f is：1/lnn-1∑k=1sk（f）/n-k, where ln：=n-1∑k=11/k.In this paper we discuss some convergence and divergence properties of this logarithmic means of the Walsh-Fourier series of functions in the uniform, and in the L^1 Lebesgue norm. Among others, as an application of our divergence results we give a negative answer to a question of Móricz concerning the convergence of logarithmic means in norm.

关键词： Walsh system Norlund logarithmic means Convergence divergence properties

Distributed Mallows Model Averaging for Ridge Regressions

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Acta Mathematica sinica,English series 2025年第2期41卷 780-826页

作者： Haili Zhang Alan t.K.Wan Kang You Guohua Zou school of undergraduate Education Shenzhen Polytechnic UniversityShenzhen 518055P.R.China Department of Management sciences and school of Data science City University of Hong KongKowloonHong Kong 999077P.R.China school of Mathematical sciences Capital Normal UniversityBeijing 100048P.R.China

Ridge regression is an effective tool to handle multicollinearity in *** is also an essential type of shrinkage and regularization methods and is widely used in big data and distributed data *** divide and conquer trick,which combines the estimator in each subset with equal weight,is commonly applied in distributed *** overcome multicollinearity and improve estimation accuracy in the presence of distributed data,we propose a Mallows-type model averaging method for ridge regressions,which combines estimators from all *** method is proved to be asymptotically optimal allowing the number of subsets and the dimension of variables to be *** consistency of the resultant weight estimators tending to the theoretically optimal weights is also ***,the asymptotic normality of the model averaging estimator is *** simulation study and real data analysis show that the proposed model averaging method often performs better than commonly used model selection and model averaging methods in distributed data cases.

关键词： Asymptotic normality asymptotic optimality consistency distributed data Mallows model averaging ridge regression

Predicting Maximum Lifespan Limits at Mean Menopausal Age

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Journal of Mathematical Research with Applications 2025年第1期45卷 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.

关键词： menopause mean menopause maximum lifespan scale parameter shape parame-ter aging modified Weibull distribution

Olfactory receptors in neural regeneration in the central nervous system

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Neural Regeneration Research 2025年第9期20卷 2480-2494页

作者： Rafael Franco Claudia Garrigós toni Capó Joan serrano-Marín Rafael Rivas-santisteban Jaume Lillo Molecular Neurobiology Laboratory Department of Biochemistry and Molecular BiomedicineFacultat de BiologiaUniversitat de BarcelonaBarcelonaSpain CiberNed Network Center for Biomedical Research in Neurodegenerative Diseases Spanish National Health Institute Carlos ⅢMadridSpain school of Chemistry Universitat de BarcelonaBarcelonaSpain Department of Biochemistry and Physiology School of Pharmacy and Food SciencesUniversitat de BarcelonaBarcelonaSpain Laboratory of Computational Medicine Biostatistics UnitFaculty of MedicineAutonomous University of BarcelonaCampus BellaterraBarcelonaSpain

Olfactory receptors are crucial for detecting odors and play a vital role in our sense of smell,influencing behaviors from food choices to emotional *** receptors also contribute to our perception of flavor and have potential applications in medical diagnostics and environmental *** ability of the olfactory system to regenerate its sensory neurons provides a unique model to study neural regeneration,a phenomenon largely absent in the central nervous *** gained from how olfactory neurons continuously replace themselves and reestablish functional connections can provide strategies to promote similar regenerative processes in the central nervous system,where damage often results in permanent *** the molecular and cellular mechanisms underpinning olfactory neuron regeneration could pave the way for developing therapeutic approaches to treat spinal co rd injuries and neurodegenerative diseases like Alzheimer's *** ctory receptors are found in almost any cell of eve ry orga n/tissue of the mammalian *** ectopic expression provides insights into the chemical structures that can activate olfactory *** addition to odors,olfactory receptors in ectopic expression may respond to endogenous compounds and molecules produced by mucosal colonizing *** analysis of the function of olfactory receptors in ectopic expression provides valuable information on the signaling pathway engaged upon receptor activation and the receptor's role in proliferation and cell differentiation *** review explo res the ectopic expression of olfa ctory receptors and the role they may play in neural regeneration within the central nervous system,with particular attention to compounds that can activate these receptors to initiate regenerative *** suggests that olfactory receptors could serve as potential therapeutic targets for enhancing neural repair and recovery following central nervous syste

关键词： adenosine receptors adrenergic receptors ectopic expression G proteincoupled receptors glia neurons

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亚洲高山流域千年尺度地表剥蚀的制约因素

中国科学:地球科学 2025年第1期55卷 75-94页

作者：杨业 steven ABINNIE 徐胜刘丛强 tibor JDuNAI 天津大学地球系统科学学院表层地球系统科学研究院天津300072 Institute of Geology and Mineralogy University of CologneCologne 50674Germany

本研究利用前人1233个亚洲高山流域沉积物宇宙成因核素^(10)Be数据统一计算了地表剥蚀速率,以约束构造、气候和地形如何影响和控制地表剥蚀过程.基于高程数据逐个像元的核素产率,使用蒙特卡洛模拟方法重新计算了^(10)Be流域剥蚀速率.剥... 详细信息

本研究利用前人1233个亚洲高山流域沉积物宇宙成因核素^(10)Be数据统一计算了地表剥蚀速率,以约束构造、气候和地形如何影响和控制地表剥蚀过程.基于高程数据逐个像元的核素产率,使用蒙特卡洛模拟方法重新计算了^(10)Be流域剥蚀速率.剥蚀速率变化范围从(7.4±0.7)mm ka^(-1)(1σ;青藏高原内部)到(9,646744+777)mm ka^(-1)(1σ;青藏高原南部)跨四个数量级,中位数为186mm ka^(-1).逐个像元计算的核素产率与传统模型使用质心坐标和平均高程计算的核素产率相比,后者96.6%核素产率被低估,其中高程差越大越被低估.两种方法计算的产率偏差可达40%,究其原因可能是流域高程分布不均和核素产率随海拔和纬度呈非线性变化.通过量化地表剥蚀速率与构造、气候、地形和岩性之间的相关性将有助于推演未知流域的剥蚀速率.从局部小尺度分析,亚热带台湾岛地区剥蚀速率可能主要受降水和新构造驱动的山体滑坡影响,而降水变化范围较窄的青藏高原东部的剥蚀速率主要受控于地形;冰川覆盖的高原地区剥蚀速率受冰川作用影响,如帕米尔、青藏高原内部和南部地区;青藏高原内部剥蚀速率较低是因为较低的降水和较高的侵蚀基准面,从而限制了河流的下切和地表起伏度演化.与局部小尺度强调单一主控因素不同,本研究对亚洲高山流域宏观大尺度进行量化分析发现:(1)地形指标(包括坡度、地形起伏度和河道陡峭指数)与剥蚀速率在千年尺度呈现一致的幂函数关系,而非简单线性;(2)剥蚀速率与气候(包括与海拔相关的降水、温度和植被覆盖度)和新构造活动(地震核密度分布)呈近似幂函数关系,为次要控制因素;(3)岩性与剥蚀速率没有明显的相关性,可能受限于流域复杂的岩性混合和低分辨率的可侵蚀指数数据.

关键词： 10Be剥蚀速率气候变化构造抬升地形梯度亚洲高山流域

A statistical Mechanical Analysis on the Bound state solution of an Energy-Dependent Deformed Hulthén Potential Energy

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Communications in theoretical Physics 2019年第9期71卷 1127-1138页

作者： B.C.Lütfüoglu A.N.Ikot u.s.Okorie A.t.Ngiangia Department of Physics Faculty of ScienceAkdeniz University07058AntalyaTurkey Department of Physics Faculty of ScienceUniversity of Hradec KraloveRokitanskeho6250003Hradec KraloveCzechia Department of Physics Theoretical Physics GroupUniversity of Port HarcourtChobaPort HarcourtNigeria Department of Physics Akwa Ibom State UniversityIkot AkpadenP.M.B.1167UyoNigeria

In this article, we investigate the bound state solution of the Klein Gordon equation under mixed vector and scalar coupling of an energy-dependent deformed Hulthén potential in D dimensions. We obtain a transcendental equation after we impose the boundary conditions. We calculate energy spectra in four different limits and in arbitrary dimension via the Newton-Raphson method. then, we use a statistical method, namely canonical partition function, and discuss the thermodynamic properties of the system in a comprehensive way. We find out that some of the thermodynamic properties overlap with each other, some of them do not.

关键词： Klein-Gordon equation energy-dependent deformed Hulthén potential energy bound state solution thermodynamic properties

thermal fracture analysis of two collinear cracks in a functionally graded medium based on the three-phase-lag model

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Applied Mathematics and Mechanics(English Edition) 2025年第3期46卷 501-520页

作者： Zhangna XuE Huameng WANG Jianlin LIu Minjie WEN Z.t.CHEN College of Pipeline and Civil Engineering China University of Petroleum(East China) school of Civil Engineering and Architecture Zhejiang Sci-Tech University Department of Mechanical Engineering University of Alberta

the three-phase-lag(tPL) heat conduction model is an accurate representation of the actual heat transfer process. It would be interesting to investigate how the tPL model affects the thermal fracture behavior when there are defects existing in the medium. this paper aims to analyze the thermoelastic responses of two collinear cracks within a functionally graded half-space under thermal loadings by means of the tPL model. the thermoelastic problem is transformed into a series of singular integral equations using the integral transformation methods. the transient temperature and stress intensity factors(sIFs) are obtained through the application of Chebyshev *** effects of crack spacing and non-homogeneous parameters on the transient thermoelastic responses are presented, and the results of the tPL model are compared with those of the Fourier model, Cattaneo and Vernotte(CV) model, and dual-phase-lag(DPL)model. It is shown that crack spacing and non-homogeneous parameters have important effects on the thermoelastic responses, and the fluctuation phenomenon under the tPL model is the most pronounced due to the existence of the thermal displacement lag term.

关键词： Chebyshev polynomials

Combinatorial therapies for spinal cord injury repair

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Neural Regeneration Research 2025年第5期20卷 1293-1308页

作者： Carla s.sousa Andreia Monteiro António J.salgado Nuno A.silva Life and Health sciences Research Institute(ICVs) School of MedicineUniversity of MinhoCampus de Gualtar-gualtarBragaPortugal ICVs/3B’s Associate Lab PT Government Associated LabCampus de Gualtar-gualtarBragaPortugal

spinal cord injuries have profound detrimental effects on individuals, regardless of whether they are caused by trauma or non-traumatic events. the compromised regeneration of the spinal cord is primarily attributed to damaged neurons, inhibitory molecules, dysfunctional immune response, and glial scarring. unfortunately, currently, there are no effective treatments available that can fully repair the spinal cord and improve functional outcomes. Nevertheless, numerous pre-clinical approaches have been studied for spinal cord injury recovery, including using biomaterials, cells, drugs, or technological-based strategies. Combinatorial treatments, which target various aspects of spinal cord injury pathophysiology, have been extensively tested in the last decade. these approaches aim to synergistically enhance repair processes by addressing various obstacles faced during spinal cord regeneration. thus, this review intends to provide scientists and clinicians with an overview of pre-clinical combinatorial approaches that have been developed toward the solution of spinal cord regeneration as well as update the current knowledge about spinal cord injury pathophysiology with an emphasis on the current clinical management.

关键词： electric stimulation neural tissue regeneration neuroprotection polytherapy spinal cord injury

saddle Point Criteria in Nonsmooth semi-Infinite Minimax Fractional Programming Problems

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Journal of systems science & Complexity 2018年第2期31卷 446-462页

作者： MIsHRA s K sINGH Yadvendra VERMA R u Department of Mathematics Banaras Hindu University Varanasi-221005 India. Department of Mathematics Texas State University USA

this paper considers a nonsmooth semi-infinite minimax fractional programming problem（sIMFP） involving locally Lipschitz invex functions. the authors establish necessary optimality conditions for sIMFP. the authors establish the relationship between an optimal solution of sIMFP and saddle point of scalar Lagrange function for sIMFP. Further, the authors study saddle point criteria of a vector Lagrange function defined for sIMFP.

关键词： Generalized convexity Lagrange function nonsmooth programming problems saddlepoint semi-infinite minimax fractional programming problems.