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An optimal rigidity theorem for complete submanifolds in a sphere

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Applied Mathematics(A Journal of Chinese Universities) 2008年第2期23卷 219-226页

作者： XU hong-wei ZHU jiao-feng Center of Math. Sci. Zhejiang Univ. Hangzhou 310027 China

It is proved that if M^n is an n-dimensional complete submanifold with parallel mean curvature vector and flat normal bundle in S^n＋p（1）, and if supM S 〈 α（n, H）, where α（n,H）=n＋n^3/2（n-1）H^2-n（n-2）/n（n-1）√n^2H^4＋4（n-1）H^2,then M^n must be the totally urnbilical sphere S^n（1/√1＋H^2）.An example to show that the pinching constant α（n, H） appears optimal is given.

关键词： submanifold rigidity flat normal bundle mean curvature.

SensFL:Privacy-Preserving Vertical Federated Learning with Sensitive Regularization

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 385-404页

作者： Chongzhen Zhang Zhichen Liu Xiangrui Xu Fuqiang Hu jiao Dai Baigen Cai wei Wang School of Automation and Intelligence Beijing Jiaotong UniversityBeijing100044China Shuohuang Railway Development Co. Ltd.National Energy GroupCangzhou062350China Beijing Key Laboratory of Security and Privacy in Intelligent Transportation School of Computer Science and TechnologyBeijing Jiaotong UniversityBeijing100044China

In the realm of Intelligent Railway Transportation Systems,effective multi-party collaboration is crucial due to concerns over privacy and data *** Federated Learning(VFL)has emerged as a promising approach to facilitate such collaboration,allowing diverse entities to collectively enhance machine learning models without the need to share sensitive training ***,existing works have highlighted VFL’s susceptibility to privacy inference attacks,where an honest but curious server could potentially reconstruct a client’s raw data from embeddings uploaded by the *** vulnerability poses a significant threat to VFL-based intelligent railway transportation *** this paper,we introduce SensFL,a novel privacy-enhancing method to against privacy inference attacks in ***,SensFL integrates regularization of the sensitivity of embeddings to the original data into the model training process,effectively limiting the information contained in shared *** reducing the sensitivity of embeddings to the original data,SensFL can effectively resist reverse privacy attacks and prevent the reconstruction of the original data from the *** experiments were conducted on four distinct datasets and three different models to demonstrate the efficacy of *** results show that SensFL can effectively mitigate privacy inference attacks while maintaining the accuracy of the primary learning *** results underscore SensFL’s potential to advance privacy protection technologies within VFL-based intelligent railway systems,addressing critical security concerns in collaborative learning environments.

关键词： Vertical federated learning privacy defenses

The curve of ion exchange ratio(%)-pH of the interaction between suspended particles with Cd(Ⅱ) in the Yellow River

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Journal of Environmental Sciences 1998年第2期10卷 125-129页

作者： Yang hong wei, jiao Xiao bao, Guo Bo shu Institute of Environmental Chemistry, Inner Mongolia Normal University, Huhhot 010022,China Yang Yu ying Department of Chemistry, Inner Mongolia Teachers College for Nationalities, China Song Zhi xi

The curve of ion exchange ratio(%) pH of the interaction between suspended particles with Cd(II) in the Yellow River was studied. The effects of lysine on this curve have been also investigated. The results showed that (1) Cadmium in Cd(OH) + form in the suspended particles exchanges with the cations. The exchange ratio of Cd 2+ is nearly at its greatest value in the range of pH (8.0—8.5) in natural aquatic system; (2) Ion exchange ratio decreases as the concentration of Cd 2+ raises from 8.9×10 -6 mol/L to 2×8.9×10 -6 mol/L; (3) At the lysine concentration of 6 8×10 -6 mol/L, it can promote the ion exchange ratio; (4) Adsorption of the suspended particles to cadmium is weaker in seawater and Jin Sha River than in the Yellow River.

关键词： liquid solid interaction cadmium ion exchange technique suspended particles Yellow River. 

沥青混合料基灌注式半刚性路面材料设计与性能试验研究

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公路 2017年第2期62卷 179-187页

作者：覃峰唐银青韦红教李春广西交通职业技术学院南宁市530023 广西交通科学研究院南宁市530007 广西道路结构与材料重点实验室南宁市530007

沥青混合料基灌注式半刚性路面是由基体沥青混合料和灌注复合水泥胶浆两部分组成,基体沥青混合料的材料组成是影响沥青混合料基灌注式半刚性路面各项性能变化的主要因素,通过对A1~A5等5种不同矿料级配组合配制空隙率为28%的基体沥青混... 详细信息

沥青混合料基灌注式半刚性路面是由基体沥青混合料和灌注复合水泥胶浆两部分组成,基体沥青混合料的材料组成是影响沥青混合料基灌注式半刚性路面各项性能变化的主要因素,通过对A1~A5等5种不同矿料级配组合配制空隙率为28%的基体沥青混合料性能测试、沥青混合料基灌注式半刚性路面材料的试件制备和不同矿料级配组合配制的基体沥青混合料灌注复合水泥胶浆形成的沥青混合料基灌注式半刚性路面的性能测定,试验结果表明:室内制备马歇尔试验试件时,水泥砂浆的灌入量为(500±10)g为宜,基体沥青混合料不同矿料级配组合对沥青混合料基灌注式半刚性路面各项性能影响较大,A4矿料级配组合配制的沥青混合料基灌注式半刚性路面综合性能最佳。该结果为沥青混合料基灌注式半刚性路面室内试验和工程施工应用提供依据。

关键词：道路工程沥青混合料基灌注式半刚性材料组成设计

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橡胶粉改性CA砂浆对轨道板受力的影响分析

西部交通科技 2015年第9期 83-87页

作者：杨洋韦红教覃峰广西交通职业技术学院广西南宁530023

文章基于橡胶粉改性CA砂浆力学性能的优越性,采用大型有限元软件ANSYS建立CRTSI型板式无砟轨道模型,研究轨道板在温度荷载与列车荷载分别作用下的应力状态,分析橡胶粉含量从0%到20%变化时,轨道板应力状态的变化情况。结果表明:温度荷载... 详细信息

文章基于橡胶粉改性CA砂浆力学性能的优越性,采用大型有限元软件ANSYS建立CRTSI型板式无砟轨道模型,研究轨道板在温度荷载与列车荷载分别作用下的应力状态,分析橡胶粉含量从0%到20%变化时,轨道板应力状态的变化情况。结果表明:温度荷载作用下,轨道板应力状态有所改善,其中,轨道板纵向拉、压应力,横向拉、压应力,板中、板角位移均随着橡胶粉含量的增大而逐渐减小,从而减轻轨道板翘曲变形;列车荷载作用下,轨道板应力状态尤其是横、纵向拉应力的最大值会随着改性CA砂浆中橡胶粉含量的增大而逐渐降低。

关键词：橡胶粉 CA砂浆无砟轨道 ANSYS 温度荷载列车荷载应力状态

The autophagy-lysosome pathway:a potential target in the chemical and gene therapeutic strategies for Parkinson’s disease

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Neural Regeneration Research 2025年第1期20卷 139-158页

作者： Fengjuan jiao Lingyan Meng Kang Du Xuezhi Li School of Mental Health Jining Medical UniversityJiningShandong ProvinceChina Shandong Collaborative Innovation Center for Diagnosis Treatment and Behavioral Interventions of Mental DisordersInstitute of Mental HealthJining Medical UniversityJiningShandong ProvinceChina

Parkinson’s disease is a common neurodegenerative disease with movement disorders associated with the intracytoplasmic deposition of aggregate proteins such asα-synuclein in *** one of the major intracellular degradation pathways,the autophagy-lysosome pathway plays an important role in eliminating these *** evidence has shown that upregulation of the autophagy-lysosome pathway may contribute to the clearance ofα-synuclein aggregates and protect against degeneration of dopaminergic neurons in Parkinson’s ***,multiple genes associated with the pathogenesis of Parkinson’s disease are intimately linked to alterations in the autophagy-lysosome ***,this pathway appears to be a promising therapeutic target for treatment of Parkinson’s *** this review,we briefly introduce the machinery of ***,we provide a description of the effects of Parkinson’s disease–related genes on the autophagy-lysosome ***,we highlight the potential chemical and genetic therapeutic strategies targeting the autophagy–lysosome pathway and their applications in Parkinson’s disease.

关键词： autophagy chemical therapy gene therapy Parkinson’s disease α-synuclein

Advances in the Development of Gradient Scaffolds Made of Nano-Micromaterials for Musculoskeletal Tissue Regeneration

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NANO-MICRO LETTERS 2025年第1期17卷 1-46页

作者： Fang, Lei Lin, Xiaoqi Xu, Ruian Liu, Lu Zhang, Yu Tian, Feng Li, jiao jiao Xue, Jiajia Beijing Univ Chem Technol Beijing Lab Biomed Mat Beijing 100029 Peoples R China Beijing Univ Chem Technol State Key Lab Organ Inorgan Composites Beijing 100029 Peoples R China Univ Technol Sydney Fac Engn & IT Sch Biomed Engn Sydney NSW 2007 Australia

This review highlights the gradient variations in the structural composition of musculoskeletal tissues and comprehensively examines recent progress in the fabrication and application of biomimetic gradient scaffolds for musculoskeletal *** challenges and prospects of gradient scaffolds for clinical application are discussed. The intricate hierarchical structure of musculoskeletal tissues, including bone and interface tissues, necessitates the use of complex scaffold designs and material structures to serve as tissue-engineered substitutes. This has led to growing interest in the development of gradient bone scaffolds with hierarchical structures mimicking the extracellular matrix of native tissues to achieve improved therapeutic outcomes. Building on the anatomical characteristics of bone and interfacial tissues, this review provides a summary of current strategies used to design and fabricate biomimetic gradient scaffolds for repairing musculoskeletal tissues, specifically focusing on methods used to construct compositional and structural gradients within the scaffolds. The latest applications of gradient scaffolds for the regeneration of bone, osteochondral, and tendon-to-bone interfaces are presented. Furthermore, the current progress of testing gradient scaffolds in physiologically relevant animal models of skeletal repair is discussed, as well as the challenges and prospects of moving these scaffolds into clinical application for treating musculoskeletal injuries.

关键词： Gradient scaffolds Musculoskeletal tissues Advanced manufacturing Biomaterials Tissue regeneration

Burkholderia pickettii中D-乙内酰脲酶基因(dha)的克隆、测序及表达

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生物工程学报 2002年第2期18卷 149-154页

作者：许祯姜卫红焦瑞身杨蕴刘中国科学院上海植物生理生态研究所上海200032

对一株能转化D ,L 对羟基苯乙内酰脲为D 对羟基苯甘氨酸的菌株MMR0 0 3进行了细菌分类学鉴定 ,该菌为皮氏伯克霍尔德氏菌 (Burkholderiapickettii)。实验通过Southern杂交 ,部分文库构建和筛选 ,并经一系列亚克隆测序分析 ,获得一长度为... 详细信息

对一株能转化D ,L 对羟基苯乙内酰脲为D 对羟基苯甘氨酸的菌株MMR0 0 3进行了细菌分类学鉴定 ,该菌为皮氏伯克霍尔德氏菌 (Burkholderiapickettii)。实验通过Southern杂交 ,部分文库构建和筛选 ,并经一系列亚克隆测序分析 ,获得一长度为 1374bp的完整开放阅读框 ,编码 45 8个氨基酸的D 乙内酰脲酶基因。用该基因序列构建的高表达质粒pXZPH2转化E .coliBL2 1(DE3) ,经IPTG诱导后 ,检测到D 乙内酰脲酶活性。该基因编码的氨基酸序列经Blast同源比较分析与放射形土壤杆菌NRRLB112 91所产相应酶有 85 %的同源性。以D ,L 对羟基苯乙内酰脲为底物测得的表达酶的活力为 0 6 6u mL ,比相同条件下所测出发菌株MMR0 0 3的酶活提高了

关键词：皮氏伯克霍尔德氏菌 D-乙内酰脲酶基因克隆表达序列分析

High-energy-density lithium manganese iron phosphate for lithium-ion batteries: Progresses, challenges, and prospects

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Journal of Energy Chemistry 2025年第1期100卷 1-17页

作者： Bokun Zhang Xiaoyun Wang Shuai Wang Yan Li Libo Chen Handong jiao Zhijing Yu Jiguo Tu State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Research Institute for Intelligent Wearable Systems The Hong Kong Polytechnic University Institute of Advanced Structure Technology Beijing Institute of Technology

The soaring demand for smart portable electronics and electric vehicles is propelling the advancements in high-energy–density lithium-ion *** manganese iron phosphate (LiMnxFe1-xPO4) has garnered significant attention as a promising positive electrode material for lithium-ion batteries due to its advantages of low cost,high safety,long cycle life,high voltage,good high-temperature performance,and high energy *** LiMnxFe1-xPO4has made significant breakthroughs in the past few decades,there are still facing great challenges in poor electronic conductivity and Li-ion diffusion,manganese dissolution affecting battery cycling performance,as well as low tap *** review systematically summarizes the reaction mechanisms,various synthesis methods,and electrochemical properties of LiMnxFe1-xPO4to analyze reaction processes accurately and guide material ***,the main challenges currently faced are concluded,and the corresponding various modification strategies are discussed to enhance the reaction kinetics and electrochemical performance of LiMnxFe1-xPO4,including multi-scale particle regulation,heteroatom doping,surface coating,as well as microscopic morphology ***,in view of the current research challenges faced by intrinsic reaction processes,kinetics,and energy storage applications,the promising research directions are *** importantly,it is expected to provide key insights into the development of high-performance and stable LiMnxFe1-xPO4materials,to achieve practical energy storage requirements.

关键词： Lithium manganese iron phosphate High energy density Lithium-ion batteries Reaction mechanism Tap density