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Universal Inequalities for Lower Order Eigenvalues of Self-Adjoint Operators and the Poly-Laplacian

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Acta Mathematica Sinica,English Series 2013年第11期29卷 2209-2218页

作者： He Jun SUN ling zhong zeng Department of Applied Mathematics Nanjing University of Science and Technology Department of Mathematics Faculty of Science and EngineeringSaga University

In this paper, we first establish an abstract inequality for lower order eigenvalues of a self-adjoint operator on a Hilbert space which generalizes and extends the recent results of Cheng et al. （Calc. Var. Partial Differential Equations, 38, 409-416 （2010））. Then, making use of it, we obtain some universal inequalities for lower order eigenvalues of the biharmonic operator on manifolds admitting some speciM functions. Moreover, we derive a universal inequality for lower order eigenvalues of the poly-Laplacian with any order on the Euclidean space.

关键词： Eigenvalue self-adjoint operator biharmonic operator poly-Laplacian Riemannian man- ifold

Analysis of gravity wave activity during stratospheric sudden warmings in the northern hemisphere

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Earth and Planetary Physics 2024年第2期8卷 415-422页

作者： XuanYun zeng Guang zhong School of Physics and Electronic Sciences Changsha University of Science and TechnologyChangsha 410000China Key Laboratory of Geospace Environment Chinese Academy of SciencesUniversity of Science&Technology of ChinaHefei 230026China

Due to the significant changes they bring to high latitude stratospheric temperature and wind,stratospheric sudden warmings(SSWs)can have an impact on the propagation and energy distribution of gravity waves(GWs).The variation characteristics of GWs during SSWs have always been an important *** temperature data from January to March in 2014−2016,provided by the Constellation Observing System for Meteorology,Ionosphere and Climate(COSMIC)mission,we have analyzed global GW activity at 15−40 km in the Northern Hemisphere during SSW *** the SSWs that we studied,the stratospheric temperature rose in one or two longitudinal regions in the Northern Hemisphere;the areas affected extended to the east of 90°*** these SSWs,the potential energy density(E_(p)of GWs expanded and covered a larger range of longitude and altitude,exhibiting an eastward and downward *** E_(p)usually increased,while partially filtered by the eastward zonal *** zonal winds weakened or turned westward,E_(p)began to *** SSWs,the E_(p)usually *** observations can serve as a reference for analyzing the interaction mechanism between SSWs and GWs in future work.

关键词： stratospheric sudden warming gravity wave wind filter

A COUPLED METHOD COMBINING CROUZEIX-RAVIART NONCONFORMING AND NODE CONFORMING FINITE ELEMENT SPACES FOR BOIT CONSOLIDATION MODEL

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Journal of Computational Mathematics 2024年第4期42卷 911-931页

作者： Yuping zeng Mingchao Cai Liuqiang zhong School of Mathematics Jiaying UniversityMeizhou 514015China Department of Mathematics Morgan State University1700 E Cold Spring LnBaltimoreMD 21251USA School of Mathematical Science South China Normal UniversityGuangzhou 520631China

A mixed finite element method is presented for the Biot consolidation problem in *** precisely,the displacement is approximated by using the Crouzeix-Raviart nonconforming finite elements,while the fuid pressure is approximated by using the node conforming finite *** well-posedness of the fully discrete scheme is established,and a corresponding priori error estimate with optimal order in the energy norm is also *** experiments are provided to validate the theoretical results.

关键词： Poroelasticity Nonconforming finite element Inf-sup condition A priori error estimate

Hexafluoropropylene oxide trimer acid,a perfluorooctanoic acid alternative,induces cardiovascular toxicity in zebrafish embryos

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Journal of Environmental Sciences 2024年第5期139卷 460-472页

作者： Sujie Sun Li Zhang Xue Li Lu Zang ling Huang Junquan zeng Zigang Cao Xinjun Liao Zilin zhong Huiqiang Lu Jianjun Chen Jiangxi Engineering Laboratory of Zebrafish Modeling and Drug Screening for Human Diseases Jiangxi Key Laboratory of Developmental Biology of OrgansCenter for Clinical Research Center of the Affiliated Hospital of Jinggangshan UniversityJi’an 343009China Translational Research Institute of Brain and Brain-like Intelligence Shanghai Key Laboratory of Anesthesiology and Brain Functional ModulationDepartment of PediatricsShanghai Fourth People’s HospitalSchool of MedicineTongji UniversityShanghai 200434China State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants School of Environmental Sciences and EngineeringShanghai Jiao Tong UniversityShanghai 200240China Department of Interventional and Vascular Surgery Affiliated Hospital of Jinggangshan UniversityJi’an 343009China Department of Internal Medicine and Hematology Affiliated Hospital of Jinggangshan UniversityJi’an 343009China

As an increasingly used alternative to perfluorooctanoic acid(PFOA),hexafluoropropylene oxide trimer acid(HFPO-TA)has been widely detected in global water ***,little is known regarding its toxic effects on cardiovascular ***,zebrafish embryos were treated with egg water containing 0,60,120,or 240 mg/L *** showed that HFPO-TA treatment led to a significant reduction in both larval survival percentage and heart ***,HFPO-TA exposure caused severe pericardial edema and elongation of the sinus venous to bulbus arteriosus distance(SV-BA)in Tg(myl7:GFP)transgenic larvae,disrupting the expression of genes involved in heart development and thus causing abnormal heart *** sprouting angiogenesis was observed in the 120 and 240 mg/L exposed Tg(fli:GFP)transgenic ***-TA treatment also impacted the mRNA levels of genes involved in the vascular endothelial growth factor(VEGF)pathway and embryonic vascular ***-TA exposure significantly decreased erythrocyte number in Tg(gata1:DsRed)transgenic embryos and influenced gene expression associated with the heme metabolism ***-TA also induced oxidative stress and altered the transcriptional levels of genes related to cell cycle and apoptosis,inhibiting cell proliferation while promoting ***,HFPO-TA exposure may induce abnormal development of the cardiovascular and hematopoietic systems in zebrafish embryos,suggesting it may not be a suitable or safe alternative for PFOA.

关键词： Hexafluoropropylene oxide trimer acid Heart development Vascular development Hemopoiesis Zebrafish embryos

Research on the MPPT of Photovoltaic Power Generation Based on Improved WOA and P&O under Partial Shading Conditions

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Energy Engineering 2024年第4期121卷 951-971页

作者： Jian zhong Lei Zhang ling Qin School of Electrical Engineering Nantong UniversityNantong226019China

Partial shading conditions(PSCs)caused by uneven illumination become one of the most common problems in photovoltaic(PV)systems,which can make the PV power-voltage(P-V)characteristics curve show *** maximum power point tracking(MPPT)methods have shortcomings in tracking to the global maximum power point(GMPP),resulting in a dramatic decrease in output *** order to solve the above problems,intelligent algorithms are used in ***,the existing intelligent algorithms have some disadvantages,such as slow convergence speed and large search ***,an improved whale algorithm(IWOA)combined with the P&O(IWOA-P&O)is proposed for the MPPT of PV power generation in this ***,IWOA is used to track the range interval of the GMPP,and then P&O is used to accurately find the MPP in that *** with other algorithms,simulation results show that this method has an average tracking efficiency of 99.79%and an average tracking time of 0.16 s when tracking ***,experimental verification is conducted,and the results show that the proposed algorithm has better MPPT performance compared to popular particle swarm optimization(PSO)and PSO-P&O algorithms.

关键词： Photovoltaic power generation maximum power point tracking whale algorithm perturbation and observation

Enabling the transfer matrix method to model serial-parallel compliant mechanisms including curved flexure beams

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International Journal of Mechanical System Dynamics 2024年第1期4卷 48-62页

作者： Mingxiang ling Lei Yuan Tingjun zeng Xianmin Zhang Robotics and Microsystems Center Soochow UniversitySoochowChina Guangdong Key Laboratory of Precision Equipment and Manufacturing Technology School of Mechanical and Automotive EngineeringSouth China University of TechnologyGuangzhouChina

Compliant mechanisms with curved flexure hinges/beams have potential advantages of small spaces,low stress levels,and flexible design parameters,which have attracted considerable attention in precision engineering,metamaterials,robotics,and so ***,serial-parallel configurations with curved flexure hinges/beams often lead to a complicated parametric ***,the transfer matrix method is enabled for analysis of both the kinetostatics and dynamics of general serial-parallel compliant mechanisms without deriving laborious formulas or combining other modeling ***,serial-parallel compliant mechanisms with curved flexure hinges/beams can be modeled in a straightforward manner based on a single transfer matrix of Timoshenko straight beams using a step-by-step *** and numerical validations on two customized XY nanopositioners comprised of straight and corrugated flexure units confirm the concise modeling process and high prediction accuracy of the presented *** conclusion,the present study provides an enhanced transfer matrix modeling approach to streamline the kinetostatic and dynamic analyses of general serial-parallel compliant mechanisms and beam structures,including curved flexure hinges and irregular-shaped rigid bodies.

关键词： compliant mechanisms curved flexure beams transfer matrix method nanopositioner rigid-body dynamics

Nickel Sulfide Modified NiCu Nanoalloy with Excellent Oxygen Evolution Reaction Properties Prepared through Electrospinning and Heat Treatment

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Journal of Wuhan University of Technology(Materials Science) 2024年第2期39卷 320-326页

作者：李涛凌帅 zhong Shujie LOU Qiongyue Department of Materials Engineering School of Mechanical EngineeringChengdu UniversityChengdu 610106China

Ni^(2+)/Cu^(2+)/SO_(4)^(2-)/polyvinyl alcohol precursor fibers with uniform diameters were prepared through ***-based composite nanoalloys containing Ni,Cu,and S were prepared through heat treatment in an Ar *** experimental results show that the main components of the prepared nanoalloys are NiCu,Ni_(3)S_(2),Ni,and *** nanoalloys exhibit fine grain sizes about 200-500 nm,which can increase with increasing heat treatment *** test results show that the nickel sulfidemodified NiCu nanoalloy composites exhibit excellent oxygen evolution reaction properties,and the oxygen evolution reaction properties gradually improve with the increasing heat treatment *** sample prepared at 1 000℃ for 40 min show a low overpotential of 423 mV and a small Tafel slope of 134 mV·dec^(-1) at a current density of 10 mA·cm^(-2).

关键词： NiCu nanoalloy Ni_(3)S_(2) structure transformation oxygen evolution reaction

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2型糖尿病患者眼表改变及危险因素分析

国际眼科杂志 2018年第12期18卷 2278-2281页

作者：曾忠玲王莉中国陕西省安康市人民医院眼科 725000 中国陕西省安康市中心医院眼科 725000

目的:分析2型糖尿病(T2DM)患者的眼表改变及危险因素。方法:纳入2017-05/2018-05收治的118例236眼T2DM患者为研究对象,另选取100例200眼非T2DM患者为对照组,进行常规眼科检查、基础泪液分泌试验(SⅠt)、泪膜破裂试验(BUT)、角膜荧光素... 详细信息

目的:分析2型糖尿病(T2DM)患者的眼表改变及危险因素。方法:纳入2017-05/2018-05收治的118例236眼T2DM患者为研究对象,另选取100例200眼非T2DM患者为对照组,进行常规眼科检查、基础泪液分泌试验(SⅠt)、泪膜破裂试验(BUT)、角膜荧光素染色试验(FL)及结膜印记细胞学检查,并收集患者病例资料进行单因素及Logistic多因素回归分析T2DM患者眼表改变的独立危险因素。结果:T2DM组眼表改变发生率22. 5%显著高于对照组7. 5%,差异有统计学意义(P <0. 05); T2DM组SⅠt、BUT、结膜杯状细胞计数均显著低于对照组,FL及结膜鳞状上皮化生程度均显著高于对照组,差异有统计学意义(P<0. 05);单因素分析结果提示,发生眼表改变的T2DM患者与未发生眼表改变的T2DM患者在年龄、病程、空腹血糖(FPG)、血浆总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)、糖化血红蛋白(HbA1c)、尿素(Urea)、肌酐(Cr)、肾小球滤过率(GRF)、24h尿蛋白(24h UP)水平比较差异有统计学意义(P<0. 05);多因素Logistic回归分析显示年龄、病程、TC、TG、LDL-C、HbA1c、Cr是影响T2DM患者眼表改变的独立危险因素。结论:T2DM患者眼表改变较正常人明显,是眼表改变的高发人群,应积极纠正T2DM患者血脂代谢紊乱,早期预防,降低眼表改变风险。

关键词： 2型糖尿病眼表改变危险因素

Efficacy of exercise rehabilitation for managing patients with Alzheimer's disease

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Neural Regeneration Research 2024年第10期19卷 2175-2188页

作者： Dan Li Jinning Jia Haibo zeng Xiaoyan zhong Hui Chen Chenju Yi Department of Pathology The First Affiliated Hospital of Gannan Medical UniversityGanzhouJiangxi ProvinceChina Department of Pathology Huichang County People’s HospitalGanzhouJiangxi ProvinceChina School of Life Sciences Faculty of ScienceUniversity of Technology SydneyUltimoNSWAustralia Research Center The Seventh Affiliated Hospital of Sun Yat-sen UniversityShenzhenGuangdong ProvinceChina Shenzhen Key Laboratory of Chinese Medicine Active Substance Screening and Translational Research ShenzhenGuangdong ProvinceChina Guangdong Provincial Key Laboratory of Brain Function and Disease GuangzhouGuangdong ProvinceChina

Alzheimer's disease(AD) is a progressive and degenerative neurological disease characterized by the deterioration of cognitive functions. While a definitive cure and optimal medication to impede disease progression are currently unavailable, a plethora of studies have highlighted the potential advantages of exercise rehabilitation for managing this condition. Those studies show that exercise rehabilitation can enhance cognitive function and improve the quality of life for individuals affected by AD. Therefore, exercise rehabilitation has been regarded as one of the most important strategies for managing patients with AD. Herein, we provide a comprehensive analysis of the currently available findings on exercise rehabilitation in patients with AD, with a focus on the exercise types which have shown efficacy when implemented alone or combined with other treatment methods, as well as the potential mechanisms underlying these positive effects. Specifically, we explain how exercise may improve the brain microenvironment and neuronal plasticity. In conclusion, exercise is a cost-effective intervention to enhance cognitive performance and improve quality of life in patients with mild to moderate cognitive dysfunction. Therefore, it can potentially become both a physical activity and a tailored intervention. This review may aid the development of more effective and individualized treatment strategies to address the challenges imposed by this debilitating disease, especially in low-and middle-income countries.

关键词： Alzheimer's disease cerebrovascular function cognitive function epigenetic regulation exercise hippocampal neurogenesis mitochondria neuroinflammation neuronal plasticity