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Forest characteristics and population structure of Glyptostrobus pensilis, a globally endangered relict species of southeastern China

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Plant Diversity 2019年第4期41卷 237-249页

作者： Cindy Q. Tang Yongchuan Yang Arata Momohara huan-Chong Wang Hong Truong Luu Shuaifeng Li Kun Song Shenhua Qian Ben LePage Yi-Fei Dong Peng-Bin Han Masahiko Ohsawa Buu Thach Le Huu dang Tran Minh Tri dang Ming-Chun Peng Chong-Yun Wang Institute of Ecology and Geobotany School of Ecology and Environmental ScienceYunnan UniversityDongwaihuan South RoadUniversity TownChenggong New DistrictKunmingYunnan 650504China The Nature Conservancy Society of Japan Mitoyo Bldg.2F1-16-10 ShinkawaChuo-kuTokyo 104-0033Japan Key Laboratory of Three Gorges Reservoir Region's Eco-Environment Ministry of EducationChongqing UniversityChongqing 400045China Graduate School of Horticulture Chiba University648 MatsudoChiba 271-8510Japan Institute of Botany Yunnan UniversityKunmingYunnan 650091China Southern Institute of Ecology Vietnam Academy o f Science and TechnologyHo Chi Minh CityViet Nam Research Institute of Resource Insects Chinese Academy of ForestryKunmingYunnan 650224China School o f Ecological and Environmental Sciences East China Normal UniversityShanghai 200241China Pacific Gas and Electric Company 3401 Crow Canyon RoadSan RamonCA 94583USA The Academy of Natural Science 1900 Benjamin Franklin ParkwayPhiladelphiaPA 19W3USA

The Chinese water pine Glyptostrobus pensilis is the sole surviving species of the genus Glyptostrobus. It is endemic to southern China, central Vietnam, and eastern Laos, and today it is nearly extinct in the wild. Forest community characteristics and population structure of G. pensilis in China have remained un-known up to now. We investigated six swamp forest stands and analyzed their forest community characteristics (i.e. vertical stratification, species composition, and diversity) and population structure, including the frequency distribution of DBH (diameter at breast height) and age-classes as found in Fujian Province, southeastern China. The vertical stratifications of all the forest stands were rather simple. The remaining wild specimens ranged from roughly 15 to some 357 years for an average of ca. 85 years, with only a few individuals less than 20 years old. Compared with the stands and populations of G. pensilis in Vietnam, the taxonomic compositions of the stands in the two regions were different, except for the dominant species-G. pensilis. The Shannon-Wiener index showed the overstory of each stand had much lower diversity (0.26 on average) in Fujian Province than that (1.97 on average) in Vietnam, whereas the diversity indices were about the same (around 2.41) for the understories in the two regions. Furthermore, we discovered 18 G. pensilis seedlings at the study sites in Fujian Province. This discovery demonstrates that G. pensilis regeneration is extremely poor and its populations are declining, although these populations are rela-tively healthier than those in Vietnam.

关键词： Age-class Fujian Province Glyptostrobus Regeneration Relict plant Vietnam

Impact of Spectral Filter on Phase Modulation Pulse in Fiber Front End System

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Chinese Physics Letters 2011年第3期28卷 89-92页

作者： LI Jing WANG Jian-Jun XU dang-Peng LIN Hong-huan GENG Yuan-Chao LI Ming-Zhong DENG Ying ZHU Na ZHANG Rui JING Feng Research Center of Laser Fusion China Academy of Engineering PhysicsPO Box 919-988Mianyang 621900

The transmission characteristics of phase modulation pulse transmitted through the filter in the power amplifier are investigated theoretically and *** narrow bandpass filter can induce large temporal modula-tion depth for the phase modulation pulse and induce double amplitude modulation(AM)if the frequency shift is lower than half bandwidth of the signal *** should choose a wider bandwidth filter to minimize the impact of the filter on the output pulse and suppress the amplified spontaneous emission(ASE)for the power fiber *** results are of benefit to the design of the fiber front end system.

关键词： amplifier fiber Impact

Flavonoids in myocardial ischemia-reperfusion injury: Therapeutic effects and mechanisms

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Chinese Herbal Medicines 2021年第1期13卷 49-63页

作者： Jun-ying Jia Er-huan Zang Li-juan Lv Qin-yu Li Chun-hua Zhang Ying Xia Lei Zhang Lian-sheng dang Min-hui Li College of Agriculture Inner Mongolia University for NationalitiesTongliao 028000China Baotou Medical College Baotou 014040China Department of Basic Science.Tianjin Agricultural University Tianjin 300384China Inner Mongolia Institute o f Traditional Chinese Medicine Hohhot 010020China Inner Mongolia Medical University Hohhot 010110China Department of Geriatrics The First Affiliated Hospital of Baotou Medical CollegeBaotou 014000China Inner Mongolia Key Laboratory of Characteristic Geoherbs Resources and Utilization Baotou Medical CollegeBaotou 014040China

Ischemic heart diseases are one of the major causes of death worldwide. Effective restoration of blood flow can significantly improve patients’ quality of life and reduce mortality. However, reperfusion injury cannot be ignored. Flavonoids possess well-established antioxidant properties;They also have other benefits that may be relevant for ameliorating myocardial ischemia-reperfusion injury(MIRI). In this review,we focus on flavonoids with cardiovascular-protection function and emphasize their pharmacological effects. The main mechanisms of flavonoid pharmacological activities against MIRI involve the following aspects: a) antioxidant, b) anti-inflammatory, c) anti-platelet aggregation, d) anti-apoptosis, and e)myocardial-function regulation activities. We also summarized the effectiveness of flavonoids for MIRI.

关键词： anti-apoptosis anti-inflammation antioxidant activity flavonoids myocardial ischemia-reperfusion injury

Reunion to Cherish Love for China——A Family from Xinjiang

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China's Ethnic Groups 2019年第1期17卷 62-68页

作者： dang Lidan Mo Ruye Wu Qiong Li huan 不详

Lina is not the kind of traditional Uzbek woman you might expect. Her blonde hair hanging down, held by a khaki hair band, fair skin with big brown eyes, wearing a dark coffee-colored trench coat with a beautiful bow at the waist, she is a capable,fashionable girl working in a state-run office and, by the way, she’s fluent in Mandarin, Russian and English.

关键词：大团圆新疆塔城中国

人血白蛋白心外科围手术期应用合理性多中心回顾性调查分析

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药物流行病学杂志 2024年第2期33卷 176-183页

作者：潘文斐于欢党大胜陈丽娟李特史天陆黄帮华李波霞弓小雪王莹中国医学科学院阜外医院药剂科北京100037 中国人民解放军北部战区总医院药剂科沈阳110016 天津市胸科医院药剂科天津300050 云南省阜外心血管病医院药剂科昆明650102 中国科学技术大学附属第一医院(安徽省立医院)药学部合肥230001 云南省第一人民医院药剂科昆明650032 兰州大学第一医院药剂科兰州730000 济宁市第一人民医院临床药学科山东济宁272000

目的调查国内多地区心外科围手术期人血白蛋白(HSA)临床应用情况,结合临床指南评价其应用合理性,为促进HSA的合理应用提供参考。方法回顾性收集2019年4—6月全国8家医院行心外科手术患者的病历资料,统计患者一般资料、HSA的用法用量、... 详细信息

目的调查国内多地区心外科围手术期人血白蛋白(HSA)临床应用情况,结合临床指南评价其应用合理性,为促进HSA的合理应用提供参考。方法回顾性收集2019年4—6月全国8家医院行心外科手术患者的病历资料,统计患者一般资料、HSA的用法用量、疗程、费用,用药前后血清白蛋白水平等信息,分析HSA的使用情况,建立相关评价标准对其应用的合理性进行评价。结果共纳入患者449例,HSA用药合理率为81.1%。用药疗程>2~5 d居多,HSA应用总量在50~99 g居多,用药目的主要为提高胶体渗透压、减轻渗出以改善间质水肿和术后扩充血容量。结论保证心外科围手术期HSA的合理应用,防止血液制品滥用需要引起临床的高度重视。

关键词：人血白蛋白临床应用回顾性调查合理用药

An Improved BP Neural Network Algorithm for Text Classification

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An Improved BP Neural Network Algorithm for Text Classificat...

基于CiteSpace可视化分析国内脊髓损伤并发低钠血症的研究热点与趋势

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作者： Fei Lei Yongbin Yu Yuxin Guo Nyima Tashi huan Zhang Bo dang School of Information and Software Engineer University of Electronic Science and Technology of China School of Information Science and Technology Tibet University

This paper presents an improved back propagation neural network（BPNN）, which highlights a novel feature selection metrics and the combination of Genetic Algorithm（GA） and BPNN. On one hand, feature selection metrics combined deflection speed and square error（DSSE） is designed to reduce dimensionality and optimize the weights of BPNN, which is capable of decreasing the training time. On the other hand, GA is introduced to optimize the hidden layer of BPNN. Experiment results demonstrate that our proposed algorithm reduces training time of 8% and improves the accuracy of prediction of 2.5%.

关键词： text classification BPNN feature selection initial weights genetic algorithm

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现代医学 2024年第1期52卷 121-126页

作者：白胶胶张欢侯妍马玉卓延安大学医学院陕西延安716000 湖南中医药大学护理学院湖南长沙410208 西安交通大学附属红会医院院办陕西西安710000

目的:通过对国内脊髓损伤(SCI)并发低钠血症相关文献进行可视化分析,了解其研究发展状况及研究热点,为后期开展相关研究提供参考。方法:计算机检索中国知网(CNKI)、中国学术期刊数据库(万方数据库)、中文科技期刊数据库(VIP)自建库至202... 详细信息

目的:通过对国内脊髓损伤(SCI)并发低钠血症相关文献进行可视化分析,了解其研究发展状况及研究热点,为后期开展相关研究提供参考。方法:计算机检索中国知网(CNKI)、中国学术期刊数据库(万方数据库)、中文科技期刊数据库(VIP)自建库至2023年7月收录的SCI并发低钠血症的相关文献。采用NoteExpress 3.***.0.9258软件合并去重,借助CiteSpace 6.1.R6软件对作者、机构、关键词绘制可视化图谱并进行解读。结果:经筛选纳入与主题相关文献190篇,发文较多的作者是张立、蔡钦林、党耕町,机构间合作较少,且发文主要出自经济发达地区。关键词分析可知,研究内容主要集中在SCI、并发症等相关领域。结论:国内对该领域的关注度有待进一步的提升,年度发文量整体呈波动趋势,近几年略有衰退。未来的研究热点将集中于SCI并发低钠的危险因素、影响因素和颈椎病。

关键词：脊髓损伤低钠可视化分析文献计量学

Effect of Solute Drag and Precipitate Pinning on Austenite Grain Growth in Ti-Nb Microalloyed Steels

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Journal of Iron and Steel Research International 2011年第S1期18卷 383-387页

作者： FU Li-ming 1,WANG huan-rong 2,WANG Wei 2,SHAN Ai-dang 1 (1.School of Materials Science and Engineering,Shanghai Jiaotong University,Shanghai 200240,China 2.Department of Structural Steels,Baosteel Research Institute,Shanghai 201900,China) Shanghai Jiao Tong Univ Sch Mat Sci & Engn Shanghai 200240 Peoples R China Baosteel Res Inst Dept Struct Steels Shanghai 201900 Peoples R China

A metallurgical model concerning the co-effect of the Nb solute drag and the complex carbonitride precipitates pinning is proposed to predict the recrystallization austenite grain growth of low carbon Nb-containing microalloyed *** analysis,both predicted and experimental,reveals the precipitate pinning plays a dominate role in suppressing the austenite grain growth with less Nb solute drag effect in high temperature region whereas the Nb solute drag predominates in relatively low temperature region.A factor p is suggested to assess the effectiveness of drag and *** pinning and the drag are more effective in restraining grain growth as p>0 and p<0,respectively.A low carbon Nb microalloyed steel and a kind of Ti-modified low carbon Nb steel by Ti substituting for part of Nb are employed to validate the modeling *** theoretical calculations show a good agreement with experimental results.

关键词： grain growth precipitates pinning solute drag Ti-Nb microalloyed steels

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僵尸网络活跃度的网络威胁预测模型研究

计算机应用研究 2014年第10期31卷 3120-3121,3130页

作者：赵焕平薛党勤南阳理工学院计算机与信息工程学院河南南阳473004 中国农业大学工学院北京100083

当前的僵尸网络预测模型大多是基于网络流量监控,而未考虑僵尸网络的规模和僵尸机的活跃度。根据僵尸网络的特点提出一种僵尸网络威胁预测模型,该预测模型综合考虑了僵尸网络的规模和活跃度,仿真实验表明这种预测模型能够对网络潜在的... 详细信息

当前的僵尸网络预测模型大多是基于网络流量监控,而未考虑僵尸网络的规模和僵尸机的活跃度。根据僵尸网络的特点提出一种僵尸网络威胁预测模型,该预测模型综合考虑了僵尸网络的规模和活跃度,仿真实验表明这种预测模型能够对网络潜在的威胁作出较为准确的预测,提高了网络的安全性。

关键词：僵尸网络分布式拒绝服务信息安全预测模型