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中国地震 2010年第3期26卷 283-295页

作者：薛艳朱元清刘双庆温燕玲宋治平中国地震局地球物理研究所中国地震台网中心上海市地震局上海200062 天津市地震局天津300201

本文围绕海啸的激发和传播两个方面简述了有限矩形源产生的地表形变场、浅水波浪理论和Boussinesq方程等基本理论,讨论了震源参数对海啸传播的影响,比较分析了海啸的数值模拟方法,介绍了我国地震海啸的研究进展等。

关键词：地震海啸震源参数浅水波方程 Boussinesq方程数值模拟方法

Netrin-1 signaling pathway mechanisms in neurodegenerative diseases

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Neural Regeneration Research 2025年第4期20卷 960-972页

作者： Kedong zhu Hualong Wang Keqiang Ye Guiqin Chen Zhaohui Zhang Department of Neurology Renmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina Department of Neurology The First Hospital of Hebei Medical UniversityBrain Aging and Cognitive Neuroscience Laboratory of Heibei ProvinceShijiazhuangHebei ProvinceChina Faculty of Life and Health Sciences Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong ProvinceChina

Netrin-1 and its receptors play crucial roles in inducing axonal growth and neuronal migration during neuronal *** profound impacts then extend into adulthood to encompass the maintenance of neuronal survival and synaptic *** amounts of evidence highlight several key points:(1)Diminished Netrin-1 levels exacerbate pathological progression in animal models of Alzheimer’s disease and Parkinson’s disease,and potentially,similar alterations occur in humans.(2)Genetic mutations of Netrin-1 receptors increase an individuals’susceptibility to neurodegenerative disorders.(3)Therapeutic approaches targeting Netrin-1 and its receptors offer the benefits of enhancing memory and motor function.(4)Netrin-1 and its receptors show genetic and epigenetic alterations in a variety of *** findings provide compelling evidence that Netrin-1 and its receptors are crucial targets in neurodegenerative *** a comprehensive review of Netrin-1 signaling pathways,our objective is to uncover potential therapeutic avenues for neurodegenerative disorders.

关键词： Alzheimer’s disease axon guidance colorectal cancer Netrin-1 receptors Netrin-1 signaling pathways Netrin-1 neurodegenerative diseases neuron survival Parkinson’s disease UNC5C

Rock fracture mechanism of buffer blasting with cushion layer at the borehole bottom

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 325-334页

作者： Xinguang zhu Chenxi Ding Zhe Sui Hong Su Xu Guo School of Civil and Resources Engineering University of Science and Technology BeijingBeijing 100083China Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing 100083China School of Chemical and Blasting Engineering Anhui University of Science and TechnologyHuainan 232001China

This study primarily investigates the rock fracture mechanism of bottom cushion layer blasting and explores the effects of the bottom cushion layer on rock *** involves analyses of the evolution patterns of blasting stress,characteristics of crack distribution,and rock fracture features in the ***,blasting model experiments were carried out using the dynamic caustics principle to investigate the influence of bottom cushion layers and initiation methods on the integrity of the bottom rock *** experimental results indicate that the combined use of bottom cushion layers and inverse initiation effectively protects the integrity of the bottom rock ***,the process of stress wave propagation and dynamic crack propagation in rocks was simulated using the continuum-discontinuum element method(CDEM)and the Landau explosion source model,with varying thicknesses of bottom cushion *** numerical simulation results indicate that with increasing cushion thickness,the absorption of energy generated by the explosion becomes more pronounced,resulting in fewer cracks in the bottom rock *** illustrates the positive role of the cushion layer in protecting the integrity of the bottom rock mass.

关键词： bottom cushion layer blasting crack propagation continuum-discontinuum element method dynamic stress intensity factor

马褂木母树林与不同来源无性系的遗传多样性比较分析

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江西农业大学学报 2021年第3期43卷 630-639页

作者：祝园青白天道王晓波胥猛蒋维昕黄寿先广西大学林学院/国家林业与草原局中南速生材繁育重点实验室广西南宁530004 全州县咸水林场广西全州541500 南京林业大学南方现代林业协同创新中心江苏南京210037

【目的】马褂木(Liriodendron chinense(Hemsl.)Sarg.)为国家二级保护珍稀树种,因其叶形独特,干形通直,木材纹理清晰,为我国优良的用材及园林绿化树种。它与该属仅存的另一种北美鹅掌楸(*** L.)均属古老的孑遗植物,具有重要的科学研究... 详细信息

【目的】马褂木(Liriodendron chinense(Hemsl.)Sarg.)为国家二级保护珍稀树种,因其叶形独特,干形通直,木材纹理清晰,为我国优良的用材及园林绿化树种。它与该属仅存的另一种北美鹅掌楸(*** L.)均属古老的孑遗植物,具有重要的科学研究价值。开展马褂木天然实生苗群体和嫁接优树群体遗传结构研究对马褂木树种的保护以及开发利用具有十分重要的意义。课题利用EST-SSR分子标记技术分析中国马褂木嫁接无性系(LC)、北美鹅掌楸嫁接无性系(LT)和中国马褂木母树林(LCS)的遗传多样性,为马褂木优良无性系评价及良种繁育工作提供参考。【方法】以广西全州咸水林场的中国及北美嫁接无性系(共35株)和全州种源的马褂木采种母树林(53株)的新鲜叶片为实验材料,利用25对EST-SSR引物进行扩增,PCR产物经8%聚丙烯酰胺胶电泳及银染分析,计算其遗传多样性参数,遗传距离,开展遗传分化和遗传聚类分析,以比较不同材料的遗传多样性及亲缘关系。【结果】遗传多样性分析表明,LT的遗传多样性参数:等位基因数(na)为4.8400,有效等位基因数(ne)为3.3386,Shannon多样性指数(I)为1.2710,观测杂合度(Ho)为0.3993,期望杂合度(He)为0.6627,基因多样度(Nei)为0.6426,普遍高于LC(na=4.0400,ne=2.8289,I=1.1080,Ho=0.3596,He=0.6115,Nei=0.5910)及LCS(na=4.1600,ne=2.4502,I=0.9634,Ho=0.3135,He=0.5141,Nei=0.5088),Kruskal-Wallis检验显示组间在ne(P=0.029)、I(P=0.036)、He(P=0.012)、Nei(P=0.029)上达到显著水平;分子方差分析(AMOVA)结果显示,群体间、群体内的遗传变异分别占总变异量的14.3%和85.7%;基于个体共祖系数的遗传结构分析表明参试材料共祖群体数(K)为3,且基于Ward最小方差法对个体间遗传距离以分组数为3进行聚类分析,可将LCS、LC及LT较好地区分。【结论】参试材料总体上具有较高的遗传多样性,其中LT遗传多样性最高,其次为LC,而LCS最低;遗传变异以群体内为主,群体间分化处于中等水平,有一定基因流(Fst=0.143,Nm=1.496);LC和LT间的亲缘关系小于LC和LCS间的亲缘关系,表明中国马褂木群体间的分化更为明显;这为马褂木优良种质资源的收集和良种繁育提供了参考。

关键词：马褂木北美鹅掌楸嫁接无性系 SSR 遗传多样性比较分析

Stabilities of delay stochastic McKean-Vlasov equations in the G-framework

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Science China(Information Sciences) 2025年第1期68卷 255-277页

作者： Haiyan YUAN Quanxin zhu Department of Mathematics Heilongjiang Institute of Technology Key Laboratory of Computing and Stochastic Mathematics (Ministry of Education) School of Mathematics and Statistics Hunan Normal University

This article focuses on a type of stochastic Mc Kean-Vlasov equation in the G-framework(G-SMVE) and addresses the stability issue for delay stochastic Mc Kean-Vlasov equations in the G-framework(G-SMVDEs). Distribution dependence and uncertainty prevent us from directly applying the stochastic analysis method for stochastic Mc Kean-Vlasov equations(SMVEs)to G-SMVEs directly. To overcome this difficulty, we introduce definitions, including the derivative of a function with a law under the G-expectation and the Lions derivatives. Then we construct a new G-It? formula for G-SMVEs according to the G-It? formula for stochastic differential equations in the G-framework(G-SDEs) and the It? formula for SMVEs. Using the new G-It? formula and the Lyapunov functional method, we investigate the moment exponential stability and almost sure asymptotic stability of G-SMVDEs. To overcome the difficulty in obtaining the distribution dependence of the exact solution to the G-SMVDE, we introduce the empirical measure and the corresponding interacting particle system, and then prove the stability equivalence between the underlying G-SMVDE and the corresponding interacting particle system. Two examples are used to confirm our theoretical results.

关键词： delay stochastic McKean-Vlasov equations Wasserstein distance G-Brownian motion Lions derivative stability

Spatio-temporal patterns and climatic drivers of spring phenology in eight forest communities across the north-south transitional zone of China

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Journal of Geographical Sciences 2025年第1期35卷 17-38页

作者： zhu Wenbin LU Yu Institute of Geographic Sciences and Natural Resources Research CAS School of Geographical Science Nanjing University of Information Science & Technology

The Qinba Mountains are climatically and ecologically recognized as the northsouth transitional zone of *** of its phenology is critical for comprehending the response of vegetation to climatic *** retrieved the start of spring phenology （SOS）of eight forest communities from the MODIS products and adopted it as an indicator for spring *** analysis,partial correlation analysis,and Geo Detector were employed to reveal the spatio-temporal patterns and climatic drivers of *** results indicated that the SOS presented an advance trend from 2001 to 2020,with a mean rate of–0.473 d yr–*** SOS of most forests correlated negatively with air temperature （TEMP） and positively with precipitation （PRE）,suggesting that rising TEMP and increasing PRE in spring would forward and delay SOS,*** dominant factors influencing the sensitivity of SOS to climatic variables were altitude,forest type,and latitude,while the effects of slope and aspect were relatively *** response of SOS to climatic factors varied significantly in space and among forest communities,partly due to the influence of altitude,slope,and aspect.

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Software-defined process-near-memory architecture using 3D hybrid bonding integration

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Science China(Information Sciences) 2025年第1期68卷 366-378页

作者： Anlin XU Chenchen DENG Jianfeng zhu Yao WANG Shaojun WEI Leibo LIU School of Integrated Circuits Tsinghua University Beijing Institution of Tracking and Communication Technology Beijing National Research Center for Information Science and Technology Tsinghua University

With the unprecedented explosive growing amount of global data, the development of computing chips, which encounter bottlenecks such as power wall and memory wall, cannot satisfy the demanding requirement. This work proposes a software-defined process-near-memory(SDPNM) computing architecture implemented using 3D hybrid bonding *** software-defined chip architecture, featuring spatial computations and dynamic reconfiguration, innovates in a top-down manner to achieve high energy efficiency while maintaining flexibility after fabrication. The process-near-memory integration further advances the SDNPM chip in a bottom-up way to reduce the energy consumption of data movement while improving the bandwidth. Utilizing a relatively mature fabrication and bonding process can result in feasible solutions for both data-intensive and compute-intensive applications including digital signal processing and artificial intelligence. The logic die is fabricated in the SMIC 40 nm process and the DRAM die is fabricated in the PSMC 25 nm process. The hybrid bonding is implemented by XMC. The experimental results show that the energy efficiency of the proposed SDPNM chip is 33.1× better than the state-of-the-art FPGA ranging from 8.2× to 104.1×.

关键词： software-defined chips process near memory energy efficiency dynamic reconfiguration domain specific

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Secure beamforming and deployment design for rate-splitting multiple access-based UAV communications

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Science China(Information Sciences) 2025年第1期68卷 342-356页

作者： Bing WANG Xiaofeng TAO Shujun HAN Huici WU Kai YANG zhu HAN National Engineering Research Center of Mobile Network Technologies Beijing University of Posts and Telecommunications Peng Cheng Laboratory Department of Electrical and Computer Engineering University of Houston

Rate-splitting multiple access(RSMA) has recently gained attention as a potential robust multiple access(MA)scheme for upcoming wireless networks. Given its ability to efficiently utilize wireless resources and design interference management strategies, it can be applied to unmanned aerial vehicle(UAV) networks to provide convenient services for large-scale access ground users. However, due to the line-of-sight(LoS) broadcast nature of UAV transmission, information is susceptible to eavesdropping in RSMA-based UAV networks. Moreover, the superposition of signals at the receiver in such networks becomes complicated. To cope with the challenge, we propose a two-user multi-input single-output(MISO) RSMA-based UAV secure transmission framework in downlink communication networks. In a passive eavesdropping scenario, our goal is to maximize the sum secrecy rate by optimizing the transmit beamforming and deployment location of the UAV-base station(UAV-BS),while considering quality-of-service(QoS) constraints, maximum transmit power, and flight space limitations. To address the non-convexity of the proposed problem, the optimization problem is first decoupled into two subproblems. Then, the successive convex approximation(SCA) method is employed to solve each subproblem using different propositions. In addition, an alternating optimization(AO)-based location RSMA(L-RSMA) beamforming algorithm is developed to implement joint optimization to obtain the suboptimal solution. Numerical results demonstrate that(1) the proposed L-RSMA scheme yields a28.97% higher sum secrecy rate than the baseline L-space division multiple access(SDMA) scheme;(2) the proposed L-RSMA scheme improves the security performance by 42.61% compared to the L-non-orthogonal multiple access(NOMA) scheme.

关键词： rate-splitting multiple access UAV communication precoding optimization deployment location physical layer security

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Wafer‑Scale Ag_(2)S‑Based Memristive Crossbar Arrays with Ultra‑Low Switching‑Energies Reaching Biological Synapses

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Nano-Micro Letters 2025年第3期17卷 328-339页

作者： Yuan zhu Tomas Nyberg Leif Nyholm Daniel Primetzhofer Xun Shi Zhen Zhang Division of Solid‑State Electronics Department of Electrical EngineeringUppsala University75121 UppsalaSweden Department of Chemistry Uppsala UniversityUppsalaSweden Department of Physics and Astronomy Uppsala UniversityUppsalaSweden State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050People’s Republic of China

Memristive crossbar arrays(MCAs)offer parallel data storage and processing for energy-efficient neuromorphic ***,most wafer-scale MCAs that are compatible with complementary metal-oxide-semiconductor(CMOS)technology still suffer from substantially larger energy consumption than biological synapses,due to the slow kinetics of forming conductive paths inside the memristive *** we report wafer-scale Ag_(2)S-based MCAs realized using CMOS-compatible processes at temperatures below 160℃.Ag_(2)S electrolytes supply highly mobile Ag+ions,and provide the Ag/Ag_(2)S interface with low silver nucleation barrier to form silver filaments at low energy *** further enhancing Ag+migration in Ag_(2)S electrolytes via microstructure modulation,the integrated memristors exhibit a record low threshold of approximately−0.1 V,and demonstrate ultra-low switching-energies reaching femtojoule values as observed in biological *** low-temperature process also enables MCA integration on polyimide substrates for applications in flexible ***,the intrinsic nonidealities of the memristive units for deep learning can be compensated by employing an advanced training *** impressive accuracy of 92.6%in image recognition simulations is demonstrated with the MCAs after the *** demonstrated MCAs provide a promising device option for neuromorphic computing with ultra-high energy-efficiency.

关键词： Wafer-scale Ag_(2)S films Reactive sputter Silver nucleation Ag^(+)migration Energy-efficient neuromorphic computing

华北地区地震学指标的定量对比筛选及其综合预报方法研究

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地震学报 1999年第2期21卷 208-213页

作者：周翠英朱元清王红卫梁凯莉李平郭爱香山东省地震局上海市地震局

在现今的地震预报工作中，地震学方法是首选且必不可少的方法．据粗略统计，目前用于我国地震预报的地震学参数有上百个之多．参数繁多，虽可任意选用，但也带来许多麻烦．“多多益善”，工作量太大，“择优录用”，难以确定哪些更好．... 详细信息

在现今的地震预报工作中，地震学方法是首选且必不可少的方法．据粗略统计，目前用于我国地震预报的地震学参数有上百个之多．参数繁多，虽可任意选用，但也带来许多麻烦．“多多益善”，工作量太大，“择优录用”，难以确定哪些更好．在国家地震局组织的实用化攻关和“八...

关键词：对比筛选法定量筛选地震学综合预报华北地区