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Structural Modal Parameter Recognition and Related Damage Identification Methods under Environmental Excitations: A Review

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Structural Durability & Health Monitoring 2025年第1期19卷 25-54页

作者： Chao Zhang Shang-Xi lai Hua-Ping Wang School of Civil Engineering and Mechanics Lanzhou UniversityLanzhou730000China Key Laboratory of Special functional Materials and Structural Design Ministry of EducationLanzhou UniversityLanzhou730000China

Modal parameters can accurately characterize the structural dynamic properties and assess the physical state of the ***,it is particularly signiﬁcant to identify the structural modal parameters according to the monitoring data information in the structural health monitoring(SHM)system,so as to provide a scientiﬁc basis for structural damage identiﬁcation and dynamic model modiﬁ*** view of this,this paper reviews methods for identifying structural modal parameters under environmental excitation and brieﬂy describes how to identify structural damages based on the derived modal *** paper primarily introduces data-driven modal parameter recognition methods(e.g.,time-domain,frequency-domain,and time-frequency-domain methods,etc.),brieﬂy describes damage identiﬁcation methods based on the variations of modal parameters(e.g.,natural frequency,modal shapes,and curvature modal shapes,etc.)and modal validation methods(e.g.,Stability Diagram and Modal Assurance Criterion,etc.).The current status of the application of artiﬁcial intelligence(AI)methods in the direction of modal parameter recognition and damage identiﬁcation is further *** on the pre-vious analysis,the main development trends of structural modal parameter recognition and damage identiﬁcation methods are given to provide scientiﬁc references for the optimized design and functional upgrading of SHM systems.

关键词： Structural health monitoring data information modal parameters damage identiﬁcation AI method

Ex vivo-expanded bone marrow stem cells home to the liver and ameliorate functional recovery in a mouse model of acute hepatic injury

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Hepatobiliary & Pancreatic Diseases International 2012年第1期11卷 66-73页

作者： Shi-Zhu Jin,Bing-Rong liu,Jun Xu,fu-lai Gao,Zong-Jing Hu,Xin-Hong Wang,Feng-Hua Pei,Yu Hong,Hong-Yan Hu and Ming-Zi Han Department of Gastroenterology and Hepatology,and Department of Science Research Management,Second Affiliated Hospital,Harbin Medical University,Harbin 150080,China Department of Gastroenterology and Hepatology,Fourth Affiliated Hospital,Harbin Medical University,Harbin 150001,China [a] Department of Gastroenterology and Hepatology Second Affliated Hospital Harbin Medical University Harbin 150080 Harbin China [b] Department of Science Research Management Second Affliated Hospital Harbin Medical University Harbin 150080 Harbin China [c] Department of Gastroenterology and Hepatology Fourth Affliated Hospital Harbin Medical University Harbin 150001 Harbin China

BACKGROUND:Stem cell transplantation provides a theoretical approach for liver regeneration medicine;it may promote liver regeneration and ***,the transplantation of bone marrow-mesenchymal stem cells expanded ex vivo as a therapy for liver disease has rarely been *** study aimed to explore whether bone marrow stem cells expanded ex vivo home to the liver and foster hepatic recovery after CCl 4 ***:Bone marrow cells from BALB/c mice were expanded ex vivo by multiple-passage cultivation,characterized by cytoflow immunofluorescence,and pre-labeled with PKH26 before intravenous infusion into animals treated with CCl *** integration of bone marrow cells into the liver was examined microscopically,and plasma hepatic enzymes were determined ***:Cultured bone marrow cells exhibited antigenic profiles comparable to those of primary medullary stem *** immunofluorescence showed colocalization of these cells with proliferative activity and albumin expression in the liver of CCl 4 -treated *** showed increased in situ cell proliferation (50±14 vs 20±3 cells/high-power field,Pfunction and survival rate in mice after CCl4-induced hepatic damage.

关键词： stem cell therapy stem cell culture acute hepatic injury

Enhancing Deepfake Detection:Proactive Forensics Techniques Using Digital Watermarking

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Computers, Materials & Continua 2025年第1期82卷 73-102页

作者： Zhimao lai Saad Arif Cong Feng Guangjun Liao Chuntao Wang School of Automation Guangdong University and TechnologyGuangzhou510006China School of Immigration Administration(Guangzhou) China People’s Police UniversityGuangzhou510663China Department of Mechanical Engineering College of EngineeringKing Faisal UniversityAl Ahsa31982Saudi Arabia Cyber Police Division Guangzhou Public Security BureauGuangzhou510030China School of Forensic Science and Technology Guangdong Police CollegeGuangzhou510320China College of Mathematics and Informatics South China Agricultural UniversityGuangzhou510642China

With the rapid advancement of visual generative models such as Generative Adversarial Networks(GANs)and stable Diffusion,the creation of highly realistic Deepfake through automated forgery has significantly *** paper examines the advancements inDeepfake detection and defense technologies,emphasizing the shift from passive detection methods to proactive digital watermarking *** detection methods,which involve extracting features from images or videos to identify forgeries,encounter challenges such as poor performance against unknown manipulation techniques and susceptibility to counter-forensic *** contrast,proactive digital watermarking techniques embed specificmarkers into images or videos,facilitating real-time detection and traceability,thereby providing a preemptive defense againstDeepfake *** offer a comprehensive analysis of digitalwatermarking-based forensic techniques,discussing their advantages over passivemethods and highlighting four key benefits:real-time detection,embedded defense,resistance to tampering,and provision of legal ***,the paper identifies gaps in the literature concerning proactive forensic techniques and suggests future research directions,including cross-domain watermarking and adaptive watermarking *** systematically classifying and comparing existing techniques,this review aims to contribute valuable insights for the development of more effective proactive defense strategies in Deepfake forensics.

关键词： Deepfake proactive forensics digital watermarking traceability detection techniques

Human neural stem cell-derived extracellular vesicles protect against ischemic stroke by activating the PI3K/AKT/mTOR pathway

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Neural Regeneration Research 2025年第11期20卷 3245-3258页

作者： Jiayi Wang Mengke Zhao Dong fu Meina Wang Chao Han Zhongyue Lv Liang Wang Jing liu Stem Cell Clinical Research Center The First Affiliated Hospital of Dalian Medical UniversityDalianLiaoning ProvinceChina Dalian Innovation Institute of Stem Cell and Precision Medicine DalianLiaoning ProvinceChina Institute(College)of Integrative Medicine Dalian Medical UniversityDalianLiaoning ProvinceChina

Human neural stem cell-derived extracellular vesicles exhibit analogous functions to their parental cells,and can thus be used as substitutes for stem cells in stem cell therapy,thereby mitigating the risks of stem cell therapy and advancing the frontiers of stem cell-derived *** lays a foundation for the development of potentially potent new treatment modalities for ischemic ***,the precise mechanisms underlying the efficacy and safety of human neural stem cell-derived extracellular vesicles remain unclear,presenting challenges for clinical *** promote the translation of therapy based on human neural stem cell-derived extracellular vesicles from the bench to the bedside,we conducted a comprehensive preclinical study to evaluate the efficacy and safety of human neural stem cell-derived extracellular vesicles in the treatment of ischemic *** found that administration of human neural stem cell-derived extracellular vesicles to an ischemic stroke rat model reduced the volume of cerebral infarction and promoted functional recovery by alleviating neuronal *** human neural stem cell-derived extracellular vesicles reduced neuronal apoptosis by enhancing phosphorylation of phosphoinositide 3-kinase,mammalian target of rapamycin,and protein kinase B,and these effects were reversed by treatment with a phosphoinositide 3-kinase *** findings suggest that human neural stem cell-derived extracellular vesicles play a neuroprotective role in ischemic stroke through activation of phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin signaling ***,we showed that human neural stem cell-derived extracellular vesicles have a good in vivo safety ***,human neural stem cell-derived extracellular vesicles are a promising potential agent for the treatment of ischemic stroke.

关键词： behavior exosome extracellular vesicles ischemic stroke mammalian target of rapamycin(mTOR) middle cerebral artery occlusion neural stem cells neuronal apoptosis phosphoinositide 3-kinase(PI3K) protein kinase B(AKT)

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南方地区双季晚稻寒露风危害研究综述

中国农业气象 2022年第1期43卷 37-49页

作者：宋忠华高文娟刘富来解娜桑友伟黄晚华中国气象局气象干部培训学院湖南分院长沙410125 气象防灾减灾湖南省重点实验室长沙410118

寒露风是双季晚稻抽穗扬花期间,因低温造成抽穗扬花受阻、空壳率增加的一种灾害性天气。为了解寒露风研究现状、继承和完善寒露风研究成果并加以突破提供借鉴和参考,本文通过对有关寒露风文献的分析和梳理,总结了寒露风研究的主要成果... 详细信息

寒露风是双季晚稻抽穗扬花期间,因低温造成抽穗扬花受阻、空壳率增加的一种灾害性天气。为了解寒露风研究现状、继承和完善寒露风研究成果并加以突破提供借鉴和参考,本文通过对有关寒露风文献的分析和梳理,总结了寒露风研究的主要成果。大气环流异常是引发大范围寒露风的根本原因,地形、地貌、海拔等因素能引起小范围寒露风。寒露风对晚稻的危害主要在抽穗开花期,其次是孕穗期。寒露风指标研究大多基于田间试验、气象要素模拟试验、生产实践以及历史数据、文献的分析,应用比较广泛的指标是“寒露风等级”和“水稻冷害评估技术规范”。寒露风预报以天气学方法较为常见、数理统计法不可或缺、神经网络等新方法的运用是一种趋势。在南方双季稻区,寒露风主要出现在9月中下旬或以后,在全球气候变暖背景下,寒露风初日呈推迟趋势、天数呈减少趋势,但存在连续多年提前和天数增加的案例。单点(站)观测、3S技术是寒露风监测常用的技术。合理安排晚稻播种期、选择耐低温品种、以水调温等多技术并举,对防御寒露风有较好效果。本文还针对寒露风研究存在的指标因子不全面、指标标准不统一、预测预报和监测评估精度达不到精细化服务的需求等主要问题,展望了未来研究的主要方向:深化寒露风多因子致灾机理及多气象要素指标研究,构建指标体系;利用大数据、人工智能等新技术,强化农业气象智能化精准预报技术研究;加强气象观测、卫星遥感及作物模型等相融合的精密监测评估技术研究;重视气候变化背景下的寒露风新规律研究;开展与气候变化及农业科技进步相适应的防灾减灾技术研究。

关键词：寒露风中国南方双季晚稻进展抽穗开花

澜沧江杂岩带小黑江-上允地区蓝片岩的成因及变质演化

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岩石矿物学杂志 2016年第5期35卷 804-820页

作者：王舫刘福来冀磊刘平华蔡佳田忠华刘利双中国地质科学院地质研究所北京100037

通过对澜沧江杂岩带小黑江-上允地区蓝片岩的岩相学、地球化学、成因矿物学以及相平衡模拟的综合研究,阐述蓝片岩的原岩以及变质演化过程。地球化学分析结果显示,蓝片岩具有一致的稀土元素配分模式,具弱Eu正或负异常,稀土元素和微量元... 详细信息

通过对澜沧江杂岩带小黑江-上允地区蓝片岩的岩相学、地球化学、成因矿物学以及相平衡模拟的综合研究,阐述蓝片岩的原岩以及变质演化过程。地球化学分析结果显示,蓝片岩具有一致的稀土元素配分模式,具弱Eu正或负异常,稀土元素和微量元素特征与OIB相似,其原岩可能为OIB型玄武岩。详细矿物学研究表明,本区蓝片岩记录了俯冲峰期蓝片岩相变质和峰期后绿片岩相变质两个变质阶段,其矿物组合分别为蓝闪石+钠长石+多硅白云母+绿泥石+绿帘石和蓝闪石+钠长石±阳起石+绿泥石+绿帘石。通过Na_2O-Ca O-Fe O-MgO-Al_2O_3-SiO_2-H_2O-O体系相平衡计算,得到两个阶段的压力范围分别约为0.95 GPa和0.40 GPa。

关键词：蓝片岩变质演化澜沧江杂岩带

点苍山-哀牢山杂岩带中北段嘎洒地区变沉积岩的成因矿物学与变质演化特征

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岩石矿物学杂志 2016年第6期35卷 1003-1024页

作者：冀磊刘福来王舫蔡佳王伟田忠华刘利双中国地质科学院地质研究所北京100037

点苍山-哀牢山变质杂岩带中北段嘎洒地区出露了多种典型的变沉积岩，其中夕线石榴黑云二长片麻岩和二云母片岩保存多期/多阶段矿物相转变特征，本文通过岩相学和矿物化学的综合分析，并结合传统矿物对温压计的估算结果，限定上述典型变... 详细信息

点苍山-哀牢山变质杂岩带中北段嘎洒地区出露了多种典型的变沉积岩，其中夕线石榴黑云二长片麻岩和二云母片岩保存多期/多阶段矿物相转变特征，本文通过岩相学和矿物化学的综合分析，并结合传统矿物对温压计的估算结果，限定上述典型变沉积岩峰期角闪-麻粒岩相（M1）阶段、近等温减压-高温剪切变形阶段（M2）和晚期退变质（M3）阶段的矿物组合及变质温压条件。峰期角闪-麻粒岩相（M1）阶段的矿物组合为：石榴石（Grt）＋板柱状夕线石（Sil1）＋黑云母（Bt1）＋钾长石（Kfs）＋斜长石（Pl）＋石英（Qtz）＋钛铁矿（Ilm），变质温度压力条件为t=690～750℃，p=690～810 MPa；近等温减压-高温剪切变形阶段（M2）阶段，稳定矿物组合为：Grt＋Sil2＋Bt2＋Kfs＋Pl＋Qtz＋Ilm，黑云母在强烈走滑剪切作用下发生脱水熔融反应：2 Bt→Sil＋6（Mg，Fe）O＋K2O＋5 Qtz＋2 H2O，石榴石、黑云母和夕线石等受到剪切变形影响而发生强烈定向，形成的温度压力条件为t=650～720℃，p=450～630 MPa；晚期退变质阶段（M3）的稳定矿物组合为：Qtz＋Bt＋Ms＋Pl，退变的温度压力条件为t=580～640℃，p=400～500 MPa。其变质演化p-T轨迹样式具有近等温减压的顺时针型式，表明点苍山-哀牢山变质杂岩带曾经历了一次明显的俯冲-碰撞造山事件，峰期变质可达到角闪-麻粒岩相；在碰撞后的构造折返过程中，上述变质岩石发生强烈的高温剪切变形作用，并伴随着黑云母等含水矿物的脱水熔融。

关键词：变沉积岩成因矿物学变质作用变质温压计变质演化嘎洒地区点苍山-哀牢山变质杂岩带

人工感染肠炎沙门氏杆菌对雏鸭脾脏SOD、POD活性和MDA含量的影响

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中国人兽共患病杂志 2005年第7期21卷 577-579页

作者：区炳庆刘富来潘燕琼冯浩罗振浩佛山科学技术学院生命科学学院广东南海528231 佛山科学技术学院兽药厂

目的用肠炎沙门氏杆菌感染雏鸭,研究肠炎沙门氏杆菌及药物治疗对雏鸭脾脏抗氧化酶等的影响,测定了脾脏组织SOD、POD活性和MDA的含量。结果表明,雏鸭脾脏SOD活性于感染12h、36h时极显著降低(P<0.01)而60h时则显著升高(P<0.05);POD活性变... 详细信息

目的用肠炎沙门氏杆菌感染雏鸭,研究肠炎沙门氏杆菌及药物治疗对雏鸭脾脏抗氧化酶等的影响,测定了脾脏组织SOD、POD活性和MDA的含量。结果表明,雏鸭脾脏SOD活性于感染12h、36h时极显著降低(P<0.01)而60h时则显著升高(P<0.05);POD活性变化较不稳定,12h显著升高(P<0.05),36h、60h呈下降趋势并显著或极显著降低(P<0.05或P<0.01),84h后显著升高(P<0.05);MDA含量于12h时则显著升高(P<0.05),随后降低(P<0.05或P<0.01);通过氟苯尼考或中草药复方制剂治疗后脾脏抗氧化酶活性也相应增强。结果说明脾脏中各种抗氧化酶参与了抵御肠炎沙门氏杆菌的过程。

关键词：肠炎沙门氏杆菌雏鸭 SOD POD MDA

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杆件考虑剪切影响时的精确解

赣南师范学院学报 2004年第6期25卷 38-40页

作者：刘福来谢宏业赣南师范学院数学与计算机系江西理工大学环境建筑学院江西赣州341000

从应用力学中两个广义位移的梁的理论出发,推导出具有两个广义位移受剪切影响的压杆和梁的微分方程式,并求出其通解,进而导出其在相应边界条件下的精确解.

关键词：广义位移剪切杆件精确解