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心血管康复医学杂志 2024年第1期33卷 113-117页

作者：周忠诚李文志哈尔滨医科大学附属第二医院麻醉科黑龙江哈尔滨150081

心房颤动(AF)是世界范围内最常见的心律失常,与患者的病死率密切相关。到目前为止,我国的患病人群已接近1000万。识别可控制的AF风险因素和制定适当的预防策略在减少致命性AF的发生和降低医疗保健系统成本方面有重大意义。AF的风险因素... 详细信息

心房颤动(AF)是世界范围内最常见的心律失常,与患者的病死率密切相关。到目前为止,我国的患病人群已接近1000万。识别可控制的AF风险因素和制定适当的预防策略在减少致命性AF的发生和降低医疗保健系统成本方面有重大意义。AF的风险因素包括肥胖、高血压、糖尿病、阻塞性睡眠呼吸暂停等,饮酒、吸烟和久坐不动的生活方式也已经被认为是AF发生发展的重要因素。本文就AF可干预的相关危险因素在AF发生发展及治疗中的作用及与AF相关的每个潜在危险因素的机制作一综述。

关键词：心房颤动危险因素生活方式

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典型海洋生态系统抗生素抗性基因研究进展

中国环境科学 2024年第6期44卷 3325-3333页

作者：王维张晓迪高会杨松岳游俊杰张银天支利文那广水海南热带海洋学院崖州湾创新研究院/海南省近岸海洋生态环境过程与碳汇重点实验室/生态环境学院海南三亚572022 国家海洋环境监测中心辽宁大连116023 中国海洋大学化学化工学院山东青岛266100

海洋生态系统中抗生素抗性基因(ARGs)污染具有隐蔽、难以治理的特征,会对生态和人类健康构成潜在风险.但目前研究多数是针对某一特定的海洋生态系统或海域,缺乏对中国海洋生态系统ARGs污染的整体概述和比较分析.本研究归纳了红树林、珊... 详细信息

海洋生态系统中抗生素抗性基因(ARGs)污染具有隐蔽、难以治理的特征,会对生态和人类健康构成潜在风险.但目前研究多数是针对某一特定的海洋生态系统或海域,缺乏对中国海洋生态系统ARGs污染的整体概述和比较分析.本研究归纳了红树林、珊瑚礁、河口以及海湾生态系统中ARGs的赋存状况,分析了其主要的传播途径和影响因素,探讨了所造成的生态风险及评估方法.结果显示,ARGs在我国典型海洋生态系统中普遍存在且组成复杂,外源输入是其流行的主要驱动因素,环境变量的调节作用也不容忽视.ARGs对海洋生态系统具有潜在危害,现有的生态风险定量评估体系尚不完善,以期为进一步全面评估和有效控制中国典型海洋生态系统中ARGs污染提供参考.

关键词：抗生素抗性基因典型海洋生态系统赋存特征生态风险

Layered niobium carbide enabling excellent kinetics and cycling stability of li-Mg-B-H hydrogen storage material Layered niobium carbide enabling excellent kinetics

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Rare Metals 2024年第3期43卷 1153-1166页

作者： li-wen Lu Hui Luo Guang-Xu li Yun li Xin-Hua Wang Cun-Ke Huang zhi-QiangLan wen-Zheng Zhou Jin Guo Mohammad Ismail Hai-Zhen liu Guangxi Novel Battery Materials Research Center of Engineering Technology Guangxi Colleges and Universities Key Laboratory of Blue Energy and Systems IntegrationSchool of Physical Science and TechnologyGuangxi UniversityNanning530004China State Key Laboratory of Featured Metal Materials and life-Cycle Safety for Composite Structures Nanning530004China School of Mechanical and Electrical Engineering Quzhou College of TechnologyQuzhou324000China Department of Materials Science and Engineering Zhejiang UniversityHangzhou310027China Faculty of Ocean Engineering Technology and Informatics Universiti Malaysia Terengganu21030Kuala NerusTerengganuMalaysia Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjin300071China

The li-Mg-B-H composite(2liBH_(4)+MgH_(2))has a high capacity of 11.4 wt%as a hydrogen storage ***,the slow kinetics and poor cycling stability severely restrict its practical *** this work,a layered Nb_(2)C MXene was first synthesized and then introduced to tailor the kinetics and cycling stability of the li-Mg-B-H *** milled 2liH+MgB_(2)composites were initially hydrogenated to obtain the 2liBH_(4)+MgH_(2)*** 2liBH_(4)+MgH_(2)+5wt%Nb_(2)C can release 9.0 wt%H_(2)in 30 min at 400℃,while it is only 2.7 wt%for the undoped 2liBH_(4)+MgH_(2).The dehydrogenation activation energies of MgH_(2)and liBH_(4)are 123 and 154 kJ·mol^(-1)respectively for the 5 wt%Nb_(2)C-doped composite,lower than the undoped composite(164 and 165 kJ·mol^(-1)).The 2liBH_(4)+MgH_(2)+5 wt%Nb_(2)C possesses excellent cycling stability,with the reversible capacity only slightly reduced from 9.4 wt%for the 1st cycle to 9.3 wt%for the 20th ***_(2)C keeps stable in the composite and acts as an efficient catalyst for the li-Mg-B-H *** is believed that both the layered structure and the active Nb element contribu te to the enhanced hydrogen storage performances of the li-Mg-B-H *** work confirms that the Nb_(2)C MXene with layered stru cture has a significant enhancing impact on the li-Mg-B-H hydrogen storage materials,which is different from the bulk NbC.

关键词： Hydrogen storage lithium borohydride Magnesium hydride Nb_(2)C MXene

基于面积差异等效建模的电液比例位置系统FMAPID控制

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科学技术与工程 2024年第27期24卷 11741-11751页

作者：康龙刘庆喜殷利建李志文冯坤鹏张新荣长安大学高速公路施工机械陕西省重点实验室西安710064 中建八局第二建设有限公司济南250014 西安长大智能装备研究所有限公司西安710018

公路边坡护坡骨架施工车是聚焦于公路边坡土壤开槽和水泥混凝土滑模的工程机械装备。针对公路边坡护坡骨架施工车旋转臂在边坡环境的运动控制问题,设计一种基于模糊多参数自适应比例积分微分(proportional integral derivative,PID)的... 详细信息

公路边坡护坡骨架施工车是聚焦于公路边坡土壤开槽和水泥混凝土滑模的工程机械装备。针对公路边坡护坡骨架施工车旋转臂在边坡环境的运动控制问题,设计一种基于模糊多参数自适应比例积分微分(proportional integral derivative,PID)的位置反馈控制策略。考虑到非对称液压缸两腔的差异,采用面积差异等效建模法建立阀控非对称液压缸的线性数学模型。通过定义模糊子集、选取隶属函数、建立模糊规则,使用模糊多参数自适应PID控制算法,实现旋转臂非对称液压缸位置控制。仿真和试验结果表明,基于面积差异等效数学模型的模糊多参数自适应PID能够有效地提高液压缸位置跟踪控制精度,验证了所提控制算法的有效性。

关键词：公路边坡护坡骨架施工车旋转臂面积差异等效电液比例位置系统模糊控制多参数自适应

LARGE EDDY SIMULATION OF THE INTERACTION BETWEEN WALL JET AND OFFSET JET

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Journal of Hydrodynamics 2011年第5期23卷 544-553页

作者： li zhi-wei HUAI wen-xin HAN Jie State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Wuhan 430072 China

The interaction between a plane wall jet and a parallel offset jet is studied through the Large Eddy Simulation （LES）. In order to compare with the related experimental data, the offset ratio is set to be 1.0 and the Reynolds number Re is 1.0× 104 with respect to the jet height L and the exit velocity U0. The Finite Volume Method （FVM） with orthogonal-mesh （6.17× 106 nodes） is used to discretize governing equations. The large eddies are obtained directly, while the small eddies are simulated by using the Dynamic Smagorinsky-lily Model （DSLM） and the Dynamic Kinetic energy Subgrid-scale Model （DKSM）. Comparisons between computational results and experimental data show that the DKSM is especially effective in predicting the mean stream-wise velocity, the half-width of the velocity and the decay of the maximum velocity. The variations of the mean stream-wise velocity and the turbulent intensity at several positions are also obtained, and their distributions agree well with the measurements. The further analysis of dilute characteristics focuses on the tracer concentration, such as the distributions of the concentration （i.e., C / C0 or C / C,,）, the boundary layer thickness 6c and the half-width of the concentration b., the decay of the maximum concentration （ C / Co） along the downstream direction. The turbulence mechanism is also analyzed in some aspects, such as the coherent structure, the correlation function and the Probability Density Function （PDF） of the fluctuating velocity. The results show that the interaction between the two jets is strong near the jet exit and they are fully merged after a certain distance.

关键词： wall jet offset jet dilute characteristic coherent structure

Baicalin protects neonatal rat brains against hypoxicischemic injury by upregulating glutamate transporter 1 via the phosphoinositide 3-kinase/protein kinase B signaling pathway

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Neural Regeneration Research 2017年第10期12卷 1625-1631页

作者： zhi-qing Zhou Yong-liang li Zhen-bo Ao zhi-li wen Qi-wen Chen Zheng-gang Huang Bing Xiao Xiao-hua Yan Department of Pediatrics the Second People's Hospital of Huaihua CityHuaihuaHunan ProvinceChina Department of Ontology the Second People's Hospital of Huaihua CityHuaihuaHunan ProvinceChina Department of Gastroenterology'the Second Affiliated Hospital of Nanchang University NanchangJiangxi ProvinceChina Department of Pediatrics the First Affiliated Hospital of Nanchang UniversityNanchangJiangxi ProvinceChina Department of Neurosurgery the Second Affiliated Hospital of Nanchang UniversityNanchangJiangxi ProvinceChina

Baicalin is a flavonoid compound extracted from Scutellaria baicalensis *** evidence indicates that baicalin is neuroprotective in models of ischemic ***,we investigate the neuroprotective effect of baicalin in a neonatal rat model of hypoxic-ischemic ***-day-old pups underwent left common carotid artery ligation followed by hypoxia（8% oxygen at 37°C） for 2 hours,before being injected with baicalin（120 mg/kg intraperitoneally） and examined 24 hours *** effectively reduced cerebral infarct volume and neuronal loss,inhibited apoptosis,and upregulated the expression of p-Akt and glutamate transporter *** injection of the phosphoinositide 3-kinase/protein kinase B（PI3 K/Akt） inhibitor LY294002 30 minutes before injury blocked the effect of baicalin on p-Akt and glutamate transporter 1,and weakened the associated neuroprotective *** findings provide the first evidence,to our knowledge that baicalin can protect neonatal rat brains against hypoxic-ischemic injury by upregulating glutamate transporter 1 via the PI3 K/Akt signaling pathway.

关键词： nerve regeneration baicalin hypoxia ischemia PI3K/Akt signaling pathway glutamate transporter 1 excitotoxicity neonatal rats apoptosis neural regeneration

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膀胱多发血管瘤1例

中国临床医学影像杂志 2024年第1期35卷 72-73页

作者：张天顺蒋超梅陈丽仙李文智朱勇华李正海曲靖市第一人民医院医学影像科云南曲靖655000

病例男,17岁。自诉3月前无明显诱因发现全程肉眼血尿,呈洗肉水样,未行治疗,门诊以“血尿查因”收入院。专科查体未见异常。超声示膀胱右侧壁及前壁稍增厚并探及多个稍强回声结节,较大者大小约1.9 cm×1.0 mm,CDFI可见少许血流信号(图1)... 详细信息

病例男,17岁。自诉3月前无明显诱因发现全程肉眼血尿,呈洗肉水样,未行治疗,门诊以“血尿查因”收入院。专科查体未见异常。超声示膀胱右侧壁及前壁稍增厚并探及多个稍强回声结节,较大者大小约1.9 cm×1.0 mm,CDFI可见少许血流信号(图1)。腹部CT平扫及增强(图2~6)示膀胱顶后壁及右侧壁增厚并多发大小不等稍高密度结节,密度稍高于膀胱壁,局部向膀胱腔内、腔外突出,较大者位于膀胱顶后壁,大小约1.7 cm×1.1 cm,CT值约45 HU,基底较宽,部分结节内见点状高密度钙化,增强扫描呈轻度延时强化,动脉期CT值约48 HU,静脉期CT值约58 HU,延时期CT值约63 HU。术前影像学检查考虑为膀胱血管瘤可能。

关键词：血管瘤膀胱肿瘤超声检查体层摄影术,X线计算机

Influences of environmental factors on the modern 14C reservoir effects in Qinghai-Tibet Plateau lakes

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Journal of Mountain Science 2021年第12期18卷 3179-3189页

作者： DU Ding-ding li zhi-wen HU Hai-ping BAI Yong-hui li wen MUGHAL Muhammad Saleem QIAN Hai-Yan East China University of Technology Key Laboratory for Digital Land and Resources of Jiangxi ProvinceNanchang 330013China Lanzhou University School of Earth SciencesLanzhou 730000China School of Environmental and Chemical Engineering Foshan UniversityFoshan 528000China Institute of Geology University of Azad Jammu and KashmirMuzaffarabad 13100Pakistan

The establishment of reliable age in the lake sediment profile mainly depends on the AMS 14C dating ***,the presence of the 14C lake reservoir effects(LREs)restricted for using radiocarbon dating in lake sediment,especially in dry and cold areas with a scarce plant cover in the Qinghai-Tibet ***,the discussion of influence factors of LREs is *** paper selected 15 lakes(17 sediment and 3 plant samples)in the Qinghai-Tibet Plateau to examine the distribution characteristics of the modern LREs and their main influencing *** our study area,14 lakes were all affected by the *** minimum 14C year is 5900 a BP towards the deep water area,whereas the maximum 14C year is up to 7185 a BP in the margins of Lake *** maximum 14C year is up to 7750 a BP,and the minimum 14C year is present-day carbon in the 15 *** further study indicated that the LRE differences in individual lake are mostly owing to the contribution of exogenous *** results displayed that the LREs tended to increase with the increase of the salinity,moreover,the LREs of saltwater lakes or salt lakes were significantly larger than freshwater lakes due to the possible supply of old total dissolved inorganic carbon with a long residence time in the ***,the contribution of calcite played a significant role on the ***,the LREs differences are affected by the source of organic *** lake with groundwater supply shows large LRE due to likely being influenced by crustal and ancient CO_(2) uprising.

关键词： Qinghai-Tibet Plateau Hydro-chemistry indexes Lake surface sediments Lake reservoir effects

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基于我国虎杖苷研究的文献计量学分析

医学信息 2024年第15期37卷 8-14页

作者：黄崇华肖建军李志文永州市第三人民医院骨科一病区

目的探讨虎杖苷领域研究现状和发展趋势，为未来临床及科研提供参考依据。方法系统检索中国知网收录的1993-2022年本领域文献，运用文献计量学软件对纳入数据进行可视化分析，基于发文趋势、学科主题分布、机构分布、作者合著性、刊... 详细信息

目的探讨虎杖苷领域研究现状和发展趋势，为未来临床及科研提供参考依据。方法系统检索中国知网收录的1993-2022年本领域文献，运用文献计量学软件对纳入数据进行可视化分析，基于发文趋势、学科主题分布、机构分布、作者合著性、刊源情况及关键词共现、聚类、突现情况，绘制网络可视化图谱。结果共纳入1013篇文献，发文量整体呈波动上升趋势，其中以中药学学科占比最多，形成以南方医科大学等院校的核心发文机构和以王兴勇、王振月和张翼为核心的热点特色团队。近年来出现较高频次及热点的关键词有细胞凋亡、氧化应激、炎症、细胞增殖、心肌细胞、动脉粥样硬化、NF-κB等。结论虎杖苷对包括心脑肾肝骨等多器官和组织具有保护作用，临床上主要用于心血管、呼吸、消化系统的疾病防治，基于细胞生物学、药理学和分子生物学等技术探索多靶点和多途径治疗疾病是未来的研究趋势。

关键词：虎杖苷白藜芦醇苷文献计量学可视化分析