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Journal of Materials Science & Technology 2000年第1期16卷 55-58页

作者： Cao, FR Cui, JZ wen, jl Lei, F Northeastern Univ Sch Met & Mat Dept Mat & Forming Control Shenyang 110006 Peoples R China

Mechanical properties and microstructure evolution of Mg-8.4 wt pet Li alloy have been investigated. The superplastic elongation-to-failure 920% at 573 K and initial strain rate of 5 x 10(-4) s(-1) at low nominal stress 2 MPa has been demonstrated. It was shown through optical microstructure that the average grain sizes at gauge length section before and after superplastic tension and at grip section were 7.5 mu m, 31.7 mu m and 20 mu m respectively, indicating significant deformation induced grain growth and static grain growth. Comparison of experiment data with published data for superplastic Mg-Li alloys shows that fine grain size and about 50 to 50 phase ratio contribute to achieving the largest superplasticity. Some related research works in other alloys are compiled and further evidences to such theoretic argument are provided.

关键词： Magnesium alloys

Dynamical complexity of Anosov systems driven by a quasi-periodic force

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Science China Mathematics 2025年第1期 89-136页

作者： wen Huang Zeng Lian Kening Lu Department of Mathematics University of Science and Technology of China School of Mathematics Sichuan University

Consider C2Anosov systems on a compact manifold driven by a quasi-periodic *** study their dynamical complexity on various levels from the perspectives of both path-wise dynamics and stochastic *** that these systems are non-wandering（i.e.,every point in the phase space is nonwandering）,we prove a set of results:（1） the existence of abundance of random periodic points;（2） a random Liv?ic theorem;（3） a random Ma?é-Bousch-Conze-Guivarc'h lemma;（4） the existence of strong random ***,a concrete example constructed on a 2-dimensional torus is also given to uncover some interesting phenomena of the systems.

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油气润滑技术在板坯连铸机中的应用

机械管理开发 2011年第5期26卷 96-97页

作者：吉文俊尤红丽中冶天工机电安装分公司中冶天工西北分公司山西太原030003

阐述了太钢二炼钢厂南区1#板坯连铸机扇形段上用油气润滑取代原干油润滑改造项目的原理、实施过程、应用特点。

关键词：油气润滑板坯连铸机滚动轴承

Targeting TrkB–PSD-95 coupling to mitigate neurological disorders

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Neural Regeneration Research 2025年第3期20卷 715-724页

作者： Xin Yang Yu-wen Alvin Huang John Marshall Department of Molecular Biology Cell Biology and BiochemistryBrown UniversityProvidenceRIUSA Department of Neurology Warren Alpert Medical School of Brown UniversityProvidenceRIUSA Center for Translational Neuroscience Robert J.and Nancy D.Carney Institute for Brain Science and Brown Institute for Translational ScienceBrown UniversityProvidenceRIUSA

Tropomyosin receptor kinase B(TrkB)signaling plays a pivotal role in dendritic growth and dendritic spine formation to promote learning and *** activity-dependent release of brain-derived neurotrophic factor at synapses binds to pre-or postsynaptic TrkB resulting in the strengthening of synapses,reflected by long-term ***,the association of postsynaptic density protein-95 with TrkB enhances phospholipase Cγ-Ca^(2+)/calmodulin-dependent protein kinaseⅡand phosphatidylinositol 3-kinase-mechanistic target of rapamycin signaling required for long-term *** this review,we discuss TrkB-postsynaptic density protein-95 coupling as a promising strategy to magnify brain-derived neurotrophic factor signaling towards the development of novel therapeutics for specific neurological disorders.A reduction of TrkB signaling has been observed in neurodegenerative disorders,such as Alzheimer's disease and Huntington's disease,and enhancement of postsynaptic density protein-95 association with TrkB signaling could mitigate the observed deficiency of neuronal connectivity in schizophrenia and *** with brain-derived neurotrophic factor is problematic,due to poor pharmacokinetics,low brain penetration,and side effects resulting from activation of the p75 neurotrophin receptor or the truncated TrkB.T1 *** TrkB agonists and antibodies that activate TrkB are being intensively investigated,they cannot distinguish the multiple human TrkB splicing isoforms or cell type-specific *** TrkB–postsynaptic density protein-95 coupling provides an alternative approach to specifically boost TrkB signaling at localized synaptic sites versus global stimulation that risks many adverse side effects.

关键词： Angelman syndrome autism brain-derived neurotrophic factor depression neurodegenerative disorder neurodevelopmental disorder postsynaptic density protein-95 synaptic plasticity TrkB

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胆管癌发生的相关危险因素病例对照研究

中华肿瘤杂志 2009年第10期31卷 759-763页

作者：陶连元何小东蔡磊刘卫纪文娟赵磊张双民中国医学科学院北京协和医学院北京协和医院基本外科 100730

目的探讨肝内胆管癌（ICC）和肝外胆管癌（ECC）发生的相关危险因素。方法收集北京协和医院1998年至2008年190例胆管癌患者的临床资料，其中ICC61例，ECC129例，并以380名健康人作为对照组。统计所有参与者的肝脏疾病、家族病史、糖尿... 详细信息

目的探讨肝内胆管癌（ICC）和肝外胆管癌（ECC）发生的相关危险因素。方法收集北京协和医院1998年至2008年190例胆管癌患者的临床资料，其中ICC61例，ECC129例，并以380名健康人作为对照组。统计所有参与者的肝脏疾病、家族病史、糖尿病、吸烟、饮酒等资料。结果ICC患者的HBsAg（＋）和anti-HBc（＋）、HBsAg（-）和anti—HBc（＋）、胆管结石的发生率分别为27．9％、50．8％和14．8％，ECC患者的糖尿病患病率、胆囊结石发生率、胆管结石发生率和胆囊切除率分别为18．6％、15．5％、18．6％和13．2％，均高于对照组（P〈0．05）。ICC与ECC相比，ICC患者有较高的肝硬化患病率（P〈0．05）。结论胆管结石、肝硬化和HBV感染是ICC发生的危险因素，而糖尿病、胆囊结石、胆管结石和胆囊切除史为ECC发生的危险因素，胆管结石是ICC和ECC发生的共同危险因素。

关键词：胆管癌肝炎病毒危险因素

核糖体蛋白基因S 26单核苷酸多态性与多囊卵巢综合征易感性的相关性研究

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中国计划生育和妇产科 2016年第11期8卷 62-66,74页

作者：梁秀文季新梅马娟深圳市龙华新区人民医院妇二科广东深圳518109

目的探讨核糖体蛋白基因S 26(ribosomal protein gene S 26,RPS 26)基因多态性与多囊卵巢综合征(polycystic ovary syndrome,PCOS)易感性的关系。方法用基因测序的方法检测2015年7月至2016年3月深圳市龙华新区人民医院诊治的100例PCOS... 详细信息

目的探讨核糖体蛋白基因S 26(ribosomal protein gene S 26,RPS 26)基因多态性与多囊卵巢综合征(polycystic ovary syndrome,PCOS)易感性的关系。方法用基因测序的方法检测2015年7月至2016年3月深圳市龙华新区人民医院诊治的100例PCOS患者和100例健康对照者RPS 26基因单核苷酸多态性位点(single nucleotide polymorphisms,SNPs)rs1131017、rs56696262基因型分布。结果 rs1131017有3种基因型C/C、C/G、G/G,基因型和等位基因分布频率在两组比较差异无统计学意义(P>0.05);rs56696262有3种基因型A/A、A/T、T/T,基因型A/T在PCOS组的分布频率高于对照组,基因型T/T在PCOS组的分布频率低于对照组,差异有统计学意义(P<0.05)。野生的T/T基因型在PCOS组分布低于对照组(P<0.05),可能为PCOS疾病发生的一种保护因素。T/T基因型患者睾酮水平低于非T/T基因型患者,差异有统计学意义(P<0.05)。结论 RPS 26基因rs56696262位点SNP与PCOS遗传易感性可能有相关性。

关键词：多囊卵巢综合征核糖体蛋白基因S 26 基因多态性

米非司酮与甲氨蝶呤联合中药保守治疗异位妊娠临床分析

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中国实用医药 2018年第8期13卷 6-8页

作者：李建霞纪雯蔡广彦青岛市第八人民医院妇科 266100

目的探讨米非司酮与甲氨蝶呤(MTX)联合中药保守治疗异位妊娠的效果。方法 100例符合保守治疗条件的异位妊娠患者,随机分为A组与B组,每组50例。A组采用米非司酮与甲氨蝶呤联合中药治疗,B组单用甲氨蝶呤治疗。比较两组的治疗效果。结果 A... 详细信息

目的探讨米非司酮与甲氨蝶呤(MTX)联合中药保守治疗异位妊娠的效果。方法 100例符合保守治疗条件的异位妊娠患者,随机分为A组与B组,每组50例。A组采用米非司酮与甲氨蝶呤联合中药治疗,B组单用甲氨蝶呤治疗。比较两组的治疗效果。结果 A组保守治疗治愈率92.00%高于B组76.00%,差异具有统计学意义(P0.05)。结论米非司酮与甲氨蝶呤联合中药治疗异位妊娠安全、有效,适用于生命体征平稳无剧烈腹痛、血β-HCG<3000 IU/L、异位妊娠包块最大直径≤5 cm非破裂型异位妊娠,肝、肾和凝血功能正常是其适应证,可作为临床首选治疗方案。

关键词：异位妊娠米非司酮甲氨蝶呤中药

Wave effect of gravitational waves intersected with a microlens field Ⅱ:An adaptive hierarchical tree algorithm and population study

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 241-254页

作者： Xikai Shan Guoliang Li Xuechun Chen wen Zhao Bin Hu Shude Mao Department of Astronomy Tsinghua University Purple Mountain Observatory Chinese Academy of Sciences Institute for Frontier in Astronomy and Astrophysics Beijing Normal University School of Physics and Astronomy Beijing Normal University School of Astronomy and Space Science University of Science and Technology of China CAS Key Laboratory for Researches in Galaxies and Cosmology Department of Astronomy University of Science and Technology of ChinaChinese Academy of Sciences

The gravitational lensing wave effect generated by a microlensing field embedded in a lens galaxy is an inevitable phenomenon in strong lensed gravitational waves （SLGWs）.This effect presents both challenges and opportunities for the detection and application of ***,investigating this wave effect requires computing a complete diffraction integral over each microlens in the *** is extremely time-consuming due to the large number of microlenses （10～3-10～6）.Therefore,simply adding all the microlenses is ***,the complexity of the time delay surface makes the lens plane resolution a crucial factor in controlling numerical *** this paper,we propose a trapezoid approximation-based adaptive hierarchical tree algorithm to meet the challenges of calculation speed and *** find that this algorithm accelerates the calculation by four orders of magnitude compared to the simple adding method and is one order of magnitude faster than the fixed hierarchical tree algorithm proposed for electromagnetic *** importantly,our algorithm ensures controllable numerical errors,increasing confidence in the *** with our previous work （***.66,239511,2023）,this paper addresses all numerical issues,including integral convergence,precision,and computational time1).Finally,we conducted a population study on the microlensing wave effect of SLGWs using this algorithm and found that the microlensing wave effect cannot be ignored,especially for Type II SLGWs （from saddle position of the time delay surface） due to their intrinsic geometric structures and their typical intersection with a denser microlensing ***,more than 33%（11%） of SLGWs have a mismatch larger than 1%（3%） compared to the unlensed ***,we found that the mismatch between signal pairs in a doubly imaged GW is generally larger than 10-3,and 61%（25%） of signal pairs have a mismatch larger than 1%（3%）.Therefo

关键词： gravitational lensing diffractional integral algorithm gravitational wave

The detection, extraction and parameter estimation of extreme-mass-ratio inspirals with deep learning

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 86-96页

作者： Qianyun Yun wen-Biao Han Yi-Yang Guo He Wang Minghui Du Hangzhou Institute for Advanced Study University of Chinese Academy of Sciences Shanghai Astronomical Observatory Chinese Academy of Sciences School of Physics and Astronomy Shanghai Jiao Tong University School of Astronomy and Space Science University of Chinese Academy of Sciences Taiji Laboratory for Gravitational Wave Universe (Beijing/Hangzhou) University of Chinese Academy of Sciences Lanzhou Center for Theoretical Physics Key Laboratory of Theoretical Physics of Gansu Province Key Laboratory of Quantum Theory and Applications of MoE Lanzhou University Institute of Theoretical Physics & Research Center of Gravitation Lanzhou University International Centre for Theoretical Physics Asia-Pacific (ICTP-AP) University of Chinese Academy of Sciences (UCAS) Center for Gravitational Wave Experiment National Microgravity Laboratory Institute of Mechanics Chinese Academy of Sciences

One of the primary goals of space-borne gravitational wave detectors is to detect and analyze extreme-mass-ratio inspirals(EMRIs). This task is particularly challenging because EMRI signals are complex, lengthy, and faint. In this work, we introduce a2-layer convolutional neural network(CNN) approach to detect EMRI signals for space-borne detectors, achieving a true positive rate(TPR) of 96.9% at a 1% false positive rate(FPR) for signal-to-noise ratio(SNR) from 50 to 100. Especially, the key intrinsic parameters of EMRIs such as the mass, spin of the supermassive black hole(SMBH) and the initial eccentricity of the orbit can also be inferred directly by employing a neural network. The mass and spin of the SMBH can be determined at 99% and 92% respectively. This will greatly reduce the parameter spaces and computing cost for the following Bayesian parameter *** model also has a low dependency on the accuracy of the waveform model. This study underscores the potential of deep learning methods in EMRI data analysis, enabling the rapid detection of EMRI signals and efficient parameter estimation.

关键词： gravitational wave EMRIs deep-learing

An efficient quantum proactive incremental learning algorithm

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 49-57页

作者： Lingxiao Li Jing Li Yanqi Song Sujuan Qin Qiaoyan wen Fei Gao State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications School of Cyberspace Security Beijing University of Posts and Telecommunications

In scenarios where a large amount of data needs to be learned, incremental learning can make full use of old knowledge, significantly reduce the computational cost of the overall learning process, and maintain high performance. In this paper, taking the MaxCut problem as our example, we introduce the idea of incremental learning into quantum computing, and propose a Quantum Proactive Incremental Learning algorithm(QPIL). Instead of a one-off training of quantum circuit, QPIL contains a multi-phase training on gradually-increased subgraphs of all vertices, proactively reducing large-scale problems to smaller ones to solve in steps, providing an efficient solution for MaxCut. Specifically, some vertices and corresponding edges are randomly selected for training to obtain optimized parameters of the quantum circuit at first. Then, in each incremental phase, the remaining vertices and corresponding edges are gradually added and the parameters obtained from the previous phase are reused in the parameter initialization of the current phase. We perform experiments on 120 different small-scale graphs, and it shows that QPIL performs superior to prevalent quantum and classical baselines in terms of approximation ratio(AR), time cost, anti-forgetting, and solving stability. In particular, QPIL's AR surpasses 20% of mainstream quantum baselines, and the time cost is less than 1/5 of them. The idea of QPIL is expected to inspire efficient and high-quality solutions in large-scale Max Cut and other combinatorial optimization problems.

关键词： variational quantum algorithm incremental learning multi-phase training MaxCut quantum computing