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Eco-evolutionary evidence for the global diversity pattern of Cycas(Cycadaceae)

Journal of Integrative Plant Biology 2024年第6期66卷 1170-1191页

作者： Jian Liu Anders JLindstrom Yiqing Gong Shanshan Dong yusheng(Chris)Liu Shouzhou Zhang xun Gong CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China Department of Economic Plants and Biotechnology Yunnan Key Laboratory for Wild Plant ResourcesKunming Institute of BotanyChinese Academy of SciencesKunming 650201China University of Chinese Academy of Sciences Beijing 100049China Global Biodiversity Conservancy 144/124 Moo3Soi Bua ThongBangsalaeSattahipChonburi 20250Thailand Key Laboratory of Southern Subtropical Plant Diversity Fairy Lake Botanical GardenShenzhen&Chinese Academy of SciencesShenzhen 518004China Department of Earth and Environmental Sciences Indiana University-IndianapolisIndianapolisIN 46202USA

The evolution of the latitudinal diversity gradient(LDG),characterized by a peak in diversity toward the tropics,has captured significant attention in evolutionary biology and ***,the inverse LDG(i-LDG)mechanism,wherein species richness increases toward the poles,remains inadequately *** are among one of the oldest lineages of extant seed plants and have undergone extensive diversification in the ***,the extant cycad abundance exhibits an i-LDG pattern,and the underlying causes for this phenomenon remain largely ***,using 1,843 nuclear genes from a nearly complete sampling,we conducted comprehensive phylogenomic analyses to establish a robust species-level phylogeny for Cycas,the largest genus within *** then reconstructed the spatial-temporal dynamics and integrated global environmental data to evaluate the roles of species ages,diversification rates,contemporary environment,and conservatism to ancestral niches in shaping the i-LDG *** found Cycas experienced decreased diversification rates,coupled with the cooling temperature since its origin in the Eocene from continental *** regions have distinctively contributed to the formation of i-LDG for Cycas,with the northern hemisphere acting as evolutionary museums and the southern hemisphere serving as ***,water-related climate variables,specifically precipitation seasonality and potential evapotranspiration,were identified as paramount factors constraining Cycas species richness in the rainforest biome near the ***,the adherence to ancestral monsoonal climates emerges as a critical factor in sustaining the diversity *** study underscores the imperative of integrating both evolutionary and ecological approaches to comprehensively unravel the mechanisms underpinning global biodiversity patterns.

关键词： cycads latitudinal diversity gradient niche conservatism spatiotemporal diversification species richness

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Correlation of CD105 and Vascular Endothelial Growth Factor in Laser-induced Choroidal Neovascularization in Rats

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眼科学报 2006年第3期22卷 166-174,183页

作者： Jianfeng xu yusheng Wang Xiumei Yang Peng Zhang Lijun Chen Department of Ophthalmology Institute of Ophthalmology of Chinese PLA X~ing HospitalFourth Military Medical University XUan 710032 China

Purpose: Choroidal neovascularization (CNV) plays an important role in pathogenesis of age-related macular degeneration (AMD), ocular histoplasmosis syndrome (OHS) and so on. However, mechanisms of CNV formation are not fully understood. The aim of this study is to investigate the correlation between expressions of CD105 and vascular endothelial growth factor (VEGF) in experimental laser-induced CNV in rats. Methods: CNV model was established by 532 nm laser photocoagulation in Brown-Norway rats. The expression of CD105 and VEGF in CNV was observed by immunohistochemistry at 3, 7, 14, 21, 28 and 56 days after laser photocoagulation. The image analysis was performed with the professional software of Image-Pro Plus. Results: Fluorescein angiography showed fluorescein leakage in CNV from days 7 to 56 after photocoagulation. VEGF expression was mainly observed in vascular endothelial cells, ganglion cells, inner nuclear layers and retinal pigment epithelial cells in normal retina and vascular endothelial cells in normal choroid of the rats. On day 3 after photocoagulation, VEGF began to express in laser-induced lesions. VEGF was strongly expressed in CNV after 7 days (P0.05). CD105 was initially presented in CNV at 7 days and obviously expressed at 14 days after photocoagulation (P0.05). There was notablely direct correlation between CD105-positive-microvessel density and positively semiquantitative scoring of VEGF in the CNV(r=0.989, P<0.01). Conclusions: There is direct correlation between the expression of CD105 and VEGF in the laser-induced CNV in rat. It suggests that CD105 and VEGF might participate in the new blood vessel formation and promote the growth of CNV.

关键词： CD105 VEGF Choroidal neovascularization Brown-Norway rat

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Achieving highly efficient long-wavelength phosphorescence emission of large singlet-triplet energy gap materials by host-guest doping

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Science China Chemistry 2024年第6期67卷 1922-1928页

作者： Shasha Zhang Wei Yao Anqi Lv Kun Liu yusheng Zhang Chifeng Zhou Huili Ma Huifang Shi Zhongfu An Key Laboratory of Flexible Electronics(KLOFE)&Institute of Advanced Materials(IAM) Nanjing Tech UniversityNanjing211816China

High-efficiency long-wavelength phosphorescence emissions of large singlet-triplet energy gap(ΔE_(ST))materials are essential for applications in biology and ***,few long-wavelength phosphorescence emissions of largeΔE_(ST)materials have been reported due to the weak spin-orbit coupling(SOC)and strong non-radiative ***,we develop a strategy to achieve highly efficient long-wavelength room temperature phosphorescence(RTP)emission of largeΔE_(ST)materials,which display bright red RTP emission with above 400μs lifetime and 6.5%phosphorescent quantum *** experiments and theoretical calculations reveal that the fishbone-like packing and the zig-zag interactions provide favorable conditions for suppressing the non-radiative transitions of triplet state excitons,and heavy atoms effectively promote the intersystem crossing(ISC)process for highly efficient long-wavelength phosphorescence *** universality of the method for highly efficient long-wavelength RTP emission of largeΔE_(ST)materials was further investigated in various ***,these materials with largeΔE_(ST)manifest the advantages of large color contrast on the display and utilization potentiality in information *** strategy paves the way for the high contrast display and development of information encryption with RTP emission.

关键词： room temperature phosphorescence singlet-triplet energy gap host-guest doping heavy atom effect red phosphorescence

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基于信息提取的面向行业应用文本分类算法

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清华大学学报（自然科学版） 2005年第S1期45卷 1810-1813页

作者：郭峰徐玉生陈晓云王颖兰州大学信息科学与工程学院兰州730000

目前,传统文本分类算法都是脱离自然语言语意的。该文使用信息抽取进行了中文文本分类的研究,提出了补偿式信息抽取的主题文本分类算法(C IETC),通过分类补偿文档属性,达到行业文档分类的目的。实验中,以将关于一个人名的所有网络文档... 详细信息

目前,传统文本分类算法都是脱离自然语言语意的。该文使用信息抽取进行了中文文本分类的研究,提出了补偿式信息抽取的主题文本分类算法(C IETC),通过分类补偿文档属性,达到行业文档分类的目的。实验中,以将关于一个人名的所有网络文档自动分类为例,验证了这种面向行业的C IETC分类器的分类性能。结果表明:该方法的分类准确率要优于B ayes方法,与KNN方法相当;该方法是一种可行的面向行业细分文本分类方法。

关键词：文本分类信息提取面向主题信息检索自然语言理解

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论新时代廉政组织与廉政文化协同反腐及其机理

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河南社会科学 2018年第3期26卷 35-40页

作者：唐忠宝徐玉生江南大学马克思主义学院江苏无锡214122

中国特色社会主义进入新时代,我党着眼于新的形势任务,发挥廉政组织与廉政文化协同作用,遏制腐败蔓延势头,取得了显著成效。一方面,发挥廉政组织的惩戒功能,以零容忍的态度惩治腐败;另一方面,培育风清气正的廉政文化,净化组织生态。以... 详细信息

中国特色社会主义进入新时代,我党着眼于新的形势任务,发挥廉政组织与廉政文化协同作用,遏制腐败蔓延势头,取得了显著成效。一方面,发挥廉政组织的惩戒功能,以零容忍的态度惩治腐败;另一方面,培育风清气正的廉政文化,净化组织生态。以廉政组织与廉政文化协同反腐,将正式约束与非正式约束有效结合,推动中国特色腐败治理创新。

关键词：新时代廉政组织廉政文化协同反腐

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Single-Component Color-Tunable Smart Organic Emitters with Simultaneous Multistage Stimuli-Responsiveness and Multimode Emissions

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Research 2024年第2期2023卷 719-728页

作者： Yu Yan Chengfang Liu Jianzhong Fan yusheng Li Huanling Liu Qian Wang Xiangchun Lil Junfeng Li Wen-Yong Lai State Key Laboratory of Organic Electronics and Information Displays(SKLOEID) Institute of Advanced Materials(IAM)School of Chemistry and Life SciencesNanjing University of Posts&Telecommunications9 Wenyuan RoadNanjng 210023China Shandong Province Key Laboratory of Medical Physics and Image Processing Technology School of Physics and ElectronicsShandong Normal UniversityJinan 250358China

Achieving color-tunable emission in single-component organic emitters with multistage stimuli-responsiveness is of vital significance for intelligent optoelectronic applications,but remains enormously ***,we present an unprecedented example of a color-tunable single-component smart organic emitter(DDOP)that simultaneously exhibits multistage stimuli-responsiveness and multimode *** based on a highly twisted amide-bridged donor-tcceptor-donor structure has been found to facilitate intersystem crossing,form multimode emissions,and generate multiple emissive species with multistage *** pristine crystalline powders exhibit abnormal excitation-dependent emissions from a monomer-dominated blue emission centered at 470 nm to a dimer-dominated yellow emission centered at 550 nm through decreasing the ultraviolet(UV)excitation wavelengths,whereas DDOP single crystals show a wide emission band with a main emission peak at 585 nm when excited at different *** emission behaviors of pristine crystalline powders and single crystals are different,demonstrating emission features that are closely related to the aggregation *** work has developed color-tunable single-component organic emitters with simultaneous multistage stimuli-responsiveness and multimode emissions,which is vital for expanding intelligent optoelectronic applications,including multilevel information encryption,multicolor emissive patterns,and visual monitoring of UV wavelengths.

关键词： donor excitation Smart

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Research on the design method for uniform wear of shield cutters in sand-pebble strata

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Deep Underground Science and Engineering 2024年第2期3卷 216-230页

作者： Jinxun Zhang Bo Li Guihe Wang yusheng Jiang Hua Jiang Minglun Yin Zhengyang Sun Beijing Urban Construction Group Co. Ltd.BeijingChina China University of Geosciences BeijingChina China University of Mining and Technology BeijingChina

During shield tunneling in highly abrasive formations such as sand–pebble strata,nonuniform wear of shield cutters is inevitable due to the different cutting *** downtimes and cutter replacements have become major obstacles to long-distance shield driving in sand–pebble *** on the cutter wear characteristics in sand–pebble strata in Beijing,a design methodology for the cutterhead and cutters was established in this study to achieve uniform wear of all cutters by the principle of frictional *** applicability of the design method was verified through three-dimensional simulations using the engineering discrete element *** results show that uniform wear of all cutters on the cutterhead could be achieved by installing different numbers of cutters on each trajectory radius and designing a curved spoke with a certain arch height according to the shield *** the uniform wear scheme,the cutter wear coefficient is greatly reduced,and the largest shield driving distance is increased by approximately 47%over the engineering *** research results indicate that the problem of nonuniform cutter wear in shield excavation could be overcome,thereby providing guiding significance for theoretical innovation and construction of long-distance shield excavation in highly abrasive strata.

关键词： cutter wear EDEM model long-distance shield driving sand-pebble stratum shield tunnel uniform wear design method

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执政能力建设的经济学分析

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上海经济研究 2005年第5期17卷 3-12页

作者：徐玉生陈志芳江南大学法政学院无锡市贸易资产经营有限公司 214000

本文基于经济学的基本原理,分析了执政能力的建设需要解决三大问题:有效增加执政资源的供给、充分降低执政成本的耗费、实现执政效率最大化的原则和路径。提出了群众认同度是衡量执政绩效的科学标准,集约化是实现执政效率最大化的路径。

关键词：执政资源执政成本执政效率有效路径

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政党生命力曲线及其时代价值探赜

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河南社会科学 2022年第8期30卷 71-79页

作者：徐玉生高梦冉江南大学马克思主义学院江苏无锡214122

政党生命力是指一个政党为实现其使命而不断增长或持续战斗的能力。政党的意识形态、领袖和党员、政党规模等都会影响政党生命力的状况。假设其他因素不变,以政党规模为自变量,以政党生命力为因变量,就可得到政党生命力曲线。这个曲线... 详细信息

政党生命力是指一个政党为实现其使命而不断增长或持续战斗的能力。政党的意识形态、领袖和党员、政党规模等都会影响政党生命力的状况。假设其他因素不变,以政党规模为自变量,以政党生命力为因变量,就可得到政党生命力曲线。这个曲线呈抛物线状,有正相关、黏滞、负相关三个阶段。政党生命力曲线对于中国共产党的时代价值,就在于警省党要不断提高自身建设质量,保持党员队伍适度规模,阻断生命力曲线拐点的出现,避免进入负相关阶段,从而永葆旺盛生命力和强大战斗力,始终成为中国人民为实现中华民族伟大复兴不懈奋斗的主心骨。

关键词：政党生命力曲线利益一致性共享观念适度规模

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论现代化进程视阈下我国的自主创新

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上海经济研究 2008年第2期20卷 77-81页

作者：张云霞徐玉生江南大学法政学院 214122

我国现代化的总体水平和特点决定了目前我国必须走自主创新之路,美、英、韩等国家的现代化历程给我们提供了有益的启示,在我国的现代化进程中,应结合国情选择自主创新的三类创新方式的组合和重点,以政产学研联盟为突破口,使我国的自主... 详细信息

我国现代化的总体水平和特点决定了目前我国必须走自主创新之路,美、英、韩等国家的现代化历程给我们提供了有益的启示,在我国的现代化进程中,应结合国情选择自主创新的三类创新方式的组合和重点,以政产学研联盟为突破口,使我国的自主创新的潜力迅速转化为自主创新的竞争力。

关键词：自主创新现代化政产学研联盟

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