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Defence Technology（防务技术） 2023年第6期24卷 414-427页

作者： Zhengjie Li Junwei xie Haowei Zhang Jiahao xie Air and Missile Defense College Air Force Engineering UniversityXi'an 710051China Space Engineering University of Strategic Support Force Beijing 101416China

The netted radar system(NRS)has been proved to possess unique advantages in anti-jamming and improving target tracking *** resource management can greatly ensure the combat capability of the *** this paper,based on the netted collocated multiple input multiple output(CMIMO)radar,an effective joint target assignment and power allocation(JTAPA)strategy for tracking multi-targets under self-defense blanket jamming is *** architecture based on the distributed fusion is used in the radar network to estimate target state *** deriving the predicted conditional Cramer-Rao lower bound(PC-CRLB)based on the obtained state estimation information,the objective function is *** maximize the worst case tracking accuracy,the proposed JTAPA strategy implements an online target assignment and power allocation of all active nodes,subject to some resource *** the formulated JTAPA is non-convex,we propose an efficient two-step solution *** terms of the simulation results,the proposed algorithm can effectively improve tracking performance in the worst case.

关键词： Netted radar system MIMO Target assignment Power allocation Multi-targets tracking Self-defense blanket jamming

酸枣仁提取物调控miR-7b-3p/5-羟色胺1A受体表达促进骨生长

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中国组织工程研究 2025年第12期29卷 2450-2457页

作者：罗石任吴晓龙谢艳河南省洛阳正骨医院(河南省骨科医院) 河南省郑州市450000

背景:前期研究发现,酸枣仁提取物通过提高脑组织5-羟色胺1A受体(serotonin 1A receptor,5-HT1AR)表达,使之与5-羟色胺结合,延长小鼠慢波睡眠,促进生长激素的分泌,从而使骨生长。5-HT1AR作为一种蛋白质,其表达丰度受到miRNA的调控。作者... 详细信息

背景:前期研究发现,酸枣仁提取物通过提高脑组织5-羟色胺1A受体(serotonin 1A receptor,5-HT1AR)表达,使之与5-羟色胺结合,延长小鼠慢波睡眠,促进生长激素的分泌,从而使骨生长。5-HT1AR作为一种蛋白质,其表达丰度受到miRNA的调控。作者推测酸枣仁提取物可能通过miRNA调控5-HT1AR的表达从而发挥药物作用。目的:观察酸枣仁提取物通过干预小鼠脑组织中miR-7b-3p/5-HT1AR通路对骨骼生长的影响。方法:①将昆明种小鼠分为正常对照组、用药组(灌胃酸枣仁提取物0.320 mg/g),阳性对照组(灌胃酸枣仁皂甙0.013 mg/g)和酸枣仁提取物+5-HT1AR抑制剂组(灌胃酸枣仁提取物最后3 d同时每天侧脑室注射5-HT1AR选择性抑制剂P-MPPF 8μg),25 d后观察酸枣仁提取物对小鼠骨生长、血清生长激素水平及脑组织5-HT1AR表达的影响;②基因芯片法筛选由酸枣仁提取物引起的骨生长小鼠与普通小鼠脑组织差异表达的miRNAs,并通过PCR验证和双荧光素酶报告基因实验证实筛选的miR-7b-3p与5-HT1AR的调控关系;③体外培养小鼠脑皮质细胞并鉴定,利用Western blot法观察酸枣仁提取物对脑皮质细胞中5-HT1AR表达的影响;④将昆明种小鼠分为正常对照组、用药组、miR-7b-3p inhibitor组、用药+miR-7b-3p mimics组、阳性对照组,观察各组小鼠脑组织5-HT1AR表达及5-羟色胺与5-HT1AR结合活性;⑤将SD大鼠分为正常对照组、用药组、miR-7b-3p inhibitor组、用药+miR-7b-3p mimics组、阳性对照组,观察各组大鼠慢波睡眠的变化。结果与结论:①酸枣仁提取物可以促进小鼠体长、胫骨增长,促进生长激素分泌,提高脑组织5-HT1AR含量;②基因芯片筛选出差异表达的miRNAs个数为16个,其中上调有13个,下调有3个;生物信息学预测下调miR-7b-3p可以调控5-HT1AR表达,且双荧光素酶报告基因实验证实二者有直接调控关系;③酸枣仁提取物和沉默脑皮质细胞中miR-7b-3p表达可以引起5-HT1AR高表达;沉默miR-7b-3p后小鼠脑组织5-HT1AR表达、5-羟色胺与5-HT1AR结合活性及生长激素分泌均升高;过表达miR-7b-3p后小鼠脑组织5-HT1AR表达、5-羟色胺与5-HT1AR结合活性及生长激素分泌均降低;大鼠慢波睡眠期也相应延长或缩短。结果表明,酸枣仁提取物能够降低脑组织的miR-7b-3p水平,同时增加5-HT1AR的表达量。这种机制有助于延长慢波睡眠周期,并且促进生长激素的生成,对骨骼生长有积极影响,为使用酸枣仁提取物作为促进骨骼生长的潜在手段提供了科学依据。

关键词：酸枣仁提取物 miR-7b-3p 脑组织 5-羟色胺 5-羟色胺1A受体生长激素

人脐带间充质干细胞条件培养基及外泌体对肝癌细胞增殖、迁移、侵袭和凋亡的影响

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中国组织工程研究 2025年第7期29卷 1350-1355页

作者：金凯唐婷李美乐谢裕安广西中医药大学研究生院广西壮族自治区南宁市530002 广西壮族自治区妇幼保健院广西壮族自治区南宁市530002 广西出生缺陷及干细胞生物样本库重点实验室广西壮族自治区南宁市530002

背景:间充质干细胞可通过分泌含细胞因子、生长因子和外泌体的细胞外囊泡调节肿瘤微环境,对肿瘤细胞生物学行为进行精准调控。目的:研究人脐带间充质干细胞条件培养基及外泌体对肝癌细胞生物学特性的影响。方法:收集人脐带间充质干细胞... 详细信息

背景:间充质干细胞可通过分泌含细胞因子、生长因子和外泌体的细胞外囊泡调节肿瘤微环境,对肿瘤细胞生物学行为进行精准调控。目的:研究人脐带间充质干细胞条件培养基及外泌体对肝癌细胞生物学特性的影响。方法:收集人脐带间充质干细胞培养上清,通过高速离心并过滤获得人脐带间充质干细胞条件培养基;收集人脐带间充质干细胞培养上清,通过超高速梯度离心法提取人脐带间充质干细胞外泌体。使用PKH26标记人脐带间充质干细胞外泌体,与肝癌细胞MHCC97-H共培养,荧光显微镜观察MHCC97-H细胞摄取外泌体情况。通过CCK-8增殖实验、Transwell迁移和侵袭实验以及流式凋亡实验评估人脐带间充质干细胞条件培养基、人脐带间充质干细胞外泌体对肝癌细胞生物学功能的影响。结果与结论:(1)人脐带间充质干细胞外泌体可被MHCC97-H细胞摄取且主要分布于细胞质中;(2)人脐带间充质干细胞条件培养基处理后,MHCC97-H细胞的增殖、迁移和侵袭能力显著增强(P<0.001,P<0.05,P<0.01),凋亡能力显著下降(P<0.001);而人脐带间充质干细胞外泌体处理后,MHCC97-H细胞的增殖能力下降(P<0.001),迁移、侵袭及凋亡能力显著增强(P<0.001);(3)结果表明,人脐带间充质干细胞条件培养基具有促进MHCC97-H细胞增殖、迁移、侵袭和抑制凋亡的能力;而人脐带间充质干细胞外泌体则具有促进MHCC97-H细胞迁移、侵袭及凋亡和抑制增殖的能力。

关键词：肝癌人脐带间充质干细胞外泌体条件培养基增殖迁移侵袭凋亡

Formation of FeNi metal nodules in the Jilin H5 chondrite,the largest stone meteorite in the world

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Acta Geochimica 2023年第6期42卷 961-970页

作者： Xiande xie Key Laboratory of Mineralogy and Metallogeny/Guangdong Provincial Key Laboratory of Mineral Physics and Materials Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China

The Jilin H5 chondrite, the largest known stony meteorite in the world, with its No.1 fragment weighing1770 kg. It contains submillimeter-to centimeter-sized FeNi metal particles/nodules. Our optical microscopic and electron microprobe analyses revealed that the formation of metal nodules in this meteorite is a complex and long-term process, The early stage is the thermal diffusion-caused migration and concentration of dispersed metallic material along fractures to form root-hair shaped metal grains during thermal metamorphism of this meteorite. The later two collision events experienced by this meteorite led to the further migration and aggregation of metallic material into the shock-produced cracks and openings to form largersized metal grains. The shock-produced shear movement and frictional heating occurred in this meteorite greatly enhanced the migration and aggregation of metallic material to form the large-sized nodules. It was revealed that the metal nodule formation process in the Jilin H5 chondrite might perform in the solid or subsolidus state, and neither melting of chondritic metal grains nor shock-induced vaporization of bulk chondrite material are related with this process.

关键词： Jilin chondrite Metal nodules Thermal diffusion Shock metamorphism Shear movement Frictional heating

Insight into the chemomechanical coupling mechanism of kinesin molecular motors

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Communications in Theoretical Physics 2021年第5期73卷 157-171页

作者： Ping xie Key Laboratory of Soft Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China

Kinesin is a two-headed biological molecular motor that can walk processively on microtubule via consumption of ATP *** central issue for the molecular motor is how the chemical energy released from ATP hydrolysis is converted to the kinetic energy of the mechanical motion,namely the mechanism of chemomechanical *** address the issue,diverse experimental methods have been employed and a lot of models have been *** review focuses on the proposed models as well as the qualitative and quantitative comparisons between the results derived from the models and those from the structural,biochemical and single-molecule experimental studies.

关键词： molecular motor kinesin dynamics mechanochemistry mechanism catch bond

Web mining based on chaotic social evolutionary programming algorithm

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Journal of Systems Engineering and Electronics 2008年第6期19卷 1272-1276页

作者： xie Bin School of Management Northwestern Polytechnical Univ. Xi'an 710072 P. R. China

With an aim to the fact that the K-means clustering algorithm usually ends in local optimization and is hard to harvest global optimization, a new web clustering method is presented based on the chaotic social evolutionary programming （CSEP） algorithm. This method brings up the manner of that a cognitive agent inherits a paradigm in clustering to enable the cognitive agent to acquire a chaotic mutation operator in the betrayal. As proven in the experiment, this method can not only effectively increase web clustering efficiency, but it can also practically improve the precision of web clustering.

关键词： web clustering chaotic social evolutionary programming K-means algorithm

The shift of biogeochemical cycles indicative of the progressive marine ecosystem collapse across the Permian-Triassic boundary:An analog to modern oceans

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Science China Earth Sciences 2018年第10期61卷 1379-1383页

作者： Shucheng xie State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences

Global warming,the most severe faunal mass extinction and the shift of biogeochemical cycles were observed in the ocean across the Permian-Triassic boundary about 252 million years ago,providing an analog to understanding the modern *** with the progressive global warming,the biogeochemical cycle was documented to show a shift from the decoupled processes of carbon,nitrogen and sulfur prior to the mass extinction to the coupled biogeochemical processes during faunal mass *** coupled biogeochemical cycle was further observed to shift from the coupled C-N processes during the first episode of the faunal mass extinction to the coupled C-N-S processes during the second episode,diagnostic of the progressive development of more deteriorated marine environmental conditions and the more severe biotic crisis across the Permian-Triassic *** biogeochemical cycles could thus be an indication to the progressive collapse of marine ecosystems triggered by the global warming in Earth *** modern oceans,the coupled C-N cycle triggered by the global warming was observed in some *** these local C-N processes develop and expand to the global oceans,the coupled C-N-S processes might be brought into existence and the marine ecosystems are inevitable to suffer from complete collapse as observed at 252 million years ago.

关键词： Microbes Mass extinction Permian-Triassic boundary Euxinia Global warming Geobiology

Sharp heat kernel estimates for spectral fractional Laplacian perturbed by gradients

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Science China Mathematics 2020年第11期63卷 2343-2362页

作者： Renming Song Longjie xie Yingchao xie Department of Mathematics University of Illinois at Urbana-ChampaignUrbanaIL 61801USA School of Mathematics and Statistics Jiangsu Normal UniversityXuzhou 221000China

Using Duhamel’s formula,we prove sharp two-sided estimates for the spectral fractional Laplacian’s heat kernel with time-dependent gradient perturbation in bounded C^1,1 *** addition,we obtain a gradient estimate as... 详细信息

关键词： spectral fractional Laplacian Dirichlet heat kernel Kato class gradient estimate

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我国未来学习中心建设现状与路径探索

大学图书情报学刊 2025年第1期43卷 37-42,65页

作者：李小涛解玲南京航空航天大学图书馆 210016 南京航空航天大学经济与管理学院 210016

建设未来学习中心,是推进高等教育数字化转型和高校图书馆服务升级的有效途径。调研未来学习中心建设现状及存在问题,可为我国高等院校未来学习中心建设实践提供参考借鉴。文章运用文献调研和网络调查的方法,从顶层设计、建设理念、空... 详细信息

建设未来学习中心,是推进高等教育数字化转型和高校图书馆服务升级的有效途径。调研未来学习中心建设现状及存在问题,可为我国高等院校未来学习中心建设实践提供参考借鉴。文章运用文献调研和网络调查的方法,从顶层设计、建设理念、空间建设、资源建设、服务创新5个维度对全国高等院校未来学习中心建设实践进行调查,并对调查结果进行归类、统计和分析。研究发现,我国未来学习中心建设正处于起步探索期,在具体实践中存在着顶层设计不足、技术应用与教学模式融合不深等问题。针对这些问题,文章提出了相应的建设路径。

关键词：未来学习中心高校图书馆建设现状网络调研

Polyhedral Feasible Set Computation of MPC-Based Optimal Control Problems

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IEEE/CAA Journal of Automatica Sinica 2018年第4期5卷 765-770页

作者： Lantao xie Lei xie Hongye Su Jingdai Wang State Key Laboratory of Industrial Control Technology Institute of Cyber-Systems and ControlZhejiang UniversityHangzhou 310027China College of Chemical and Biological Engineering Zhejiang UniversityHangzhou 310027China IEEE

Feasible sets play an important role in model predictive control(MPC) optimal control problems(OCPs). This paper proposes a multi-parametric programming-based algorithm to compute the feasible set for OCP derived from MPC-based algorithms involving both spectrahedron(represented by linear matrix inequalities) and polyhedral(represented by a set of inequalities) constraints. According to the geometrical meaning of the inner product of vectors, the maximum length of the projection vector from the feasible set to a unit spherical coordinates vector is computed and the optimal solution has been proved to be one of the vertices of the feasible set. After computing the vertices,the convex hull of these vertices is determined which equals the feasible set. The simulation results show that the proposed method is especially efficient for low dimensional feasible set computation and avoids the non-unicity problem of optimizers as well as the memory consumption problem that encountered by projection algorithms.

关键词： Feasible set computation linear matrix inequalities(LMIs) model predictive control(MPC) polyhedron