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An unprotected vulnerable relict subtropical conifer-Keteleeria evelyniana: Its forests, populations, growth and endangerment by invasive alien plant species in China

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Plant Diversity 2024年第5期46卷 648-660页

作者： Cindy Q.Tang Min-Rui Du Huan-Chong Wang You-Cai Shi Jia-Le Zeng shu-li xiao Peng-Bin Han Jian-Ran Wen Shi-Qian Yao Ming-Chun Peng Chong-Yun Wang Yong-Ping li Jordi López-Pujol Institute of Ecology and Geobotany College of Ecology and Environmental ScienceYunnan UniversityBuilding#3Guozhong DalouDongwaihuan South RoadUniversity TownChenggong New DistrictKunming 650504YunnanChina College of life Sciences Yunnan UniversityShengming Kexueyuan Building#2Chenggong CampusDongwaihuan South RoadUniversity TownChenggong New DistrictKunming 650504YunnanChina College of Natural Resources Yunnan UniversityChenggong CampusDongwaihuan South RoadUniversity TownChenggong New DistrictKunming 650504YunnanChina Botanic Institute of Barcelona(IBB CSIC-CMCNC)Passeig del Migdia s/nBarcelona 08038CataloniaSpain Escuela de Ciencias Ambientales Universidad Espíritu Santo(UEES)Samborondon 091650Ecuador

Relict subtropical coniferous forests in China face severe fragmentation,resulting in declining populations,and some are under significant threat from invasive alien *** the crucial importance of understanding forest dynamics,knowledge gaps persist,particularly regarding the impact of invasive plants on vulnerable natives like Keteleeria *** this study,we investigated the impact of invasive plants on the regeneration of forests dominated by ***,a subtropical relict species in southwestern *** this purpose,we characterized forest dynamics of 160 forest plots featuring *** as the primary dominant species and determined whether the presence of invasive plants was correlated with regeneration of *** identified four distinct forest types in which *** was *** found that radial growth of *** trees is faster in younger ageclasses today than it was for older trees at the same *** population structure of *** in each forest type exhibited a multimodal age-class ***,three forest types lacked established saplings younger than 10 years old,a situation attributed to the dense coverage of the invasive alien Ageratina *** invasive species resulted in a reduction of understory species ***,our analysis uncovered a significant negative correlation in phylogenetic relatedness(net relatedness index)between native and invasive alien plant species in eastern *** suggests closely related invasive species face heightened competition,hindering successful *** together,our findings indicate that successful establishment and habitat restoration of *** seedling/saplings require effective measures to control invasive plants.

关键词： Keteleeria evelyniana Age structure Regeneration Species diversity Invasive alien species Phylogenetic relatedness

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生涯适应力对中学生学业成绩的影响机制研究

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韩山师范学院学报 2024年第3期45卷 59-67页

作者：舒晓丽郑斌锐韩山师范学院教育科学学院广东潮州521041 潮州市湘桥区城南中学广东潮州521000

为了探讨生涯适应力对中学生学业成绩的影响及其中介机制,采用整群随机抽样的方法共收集了788名中学生的数据.研究发现生涯适应力正向预测中学生学业成绩;教师支持在生涯适应力和学业成绩之间起中介作用;未来工作自我清晰度在生涯适应... 详细信息

为了探讨生涯适应力对中学生学业成绩的影响及其中介机制,采用整群随机抽样的方法共收集了788名中学生的数据.研究发现生涯适应力正向预测中学生学业成绩;教师支持在生涯适应力和学业成绩之间起中介作用;未来工作自我清晰度在生涯适应力和学业成绩之间起中介作用;教师支持和未来工作自我清晰度在生涯适应力和学业成绩之间起链式中介作用.

关键词：生涯适应力中学生教师支持未来工作自我清晰度学业成绩

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Non-dimensional analysis of static bifurcation in a natural circulation loop

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Nuclear Science and Techniques 2006年第1期17卷 61-64页

作者： TONG li-li li Tian-shu li xiao-Yan Department of Nuclear Science and System Engineering Shanghai Jiaotong University Shanghai 200030 China

The steady-state characteristics of a two-phase natural circulation loop were investigated based on the homogenous model. Transcendental equations of non-dimensional loop mass flow rate under various conditions were also derived. The static bifurcation diagram of a two-phase natural circulation described with non-dimensional vari-ables Npch-m + was obtained. In addition, various steady-state characteristics of a natural circulation loop were ana-lyzed and discussed. These characteristics include the existence of multiple solutions under certain conditions, and the maximum mass flow rate. The authors also examined the effects of important parameters such as sub-cooling number, riser-to-heated-region length ratio, and riser-to-heated-region diameter ratio.

关键词：静态分歧自然循环回路双相自然循环非空间分析

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Gut microbiome:New perspectives for type 2 diabetes prevention and treatment

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World Journal of Clinical Cases 2023年第31期11卷 7508-7520页

作者： shu-xiao li Yan Guo School of Clinical Medicine Changchun University of Traditional Chinese MedicineChangchun 130000Jilin ProvinceChina

Type 2 diabetes mellitus(T2DM),which is distinguished by increased glucose levels in the bloodstream,is a metabolic disease with a rapidly increasing incidence ***,the etiology and characteristics of the mechanism of T2DM remain ***,abundant evidence has indicated that the intestinal microbiota is crucially involved in the initiation and progression of *** gut microbiome,the largest microecosystem,engages in material and energy metabolism in the human *** this review,we concentrated on the correlation between the gut flora and ***,we summarized the pathogenesis involving the intestinal flora in T2DM,as well as therapeutic approaches aimed at modulating the gut microbiota for the management of *** the analysis presented here,we draw attention to further exploration of these research directions.

关键词： Microbial metabolites Intestinal flora Probiotics Insulin resistance Type 2 diabetes

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Efects of thermal aging temperature and Cr content on phase separ-ation kinetics in Fe-Cr alloys simulated by the phase feld method

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International Journal of Minerals,Metallurgy and Materials 2013年第11期20卷 1067-1075页

作者： shu-xiao li Hai-long Zhang Shi-lei li Yan-li Wang Fei Xue Xi-tao Wang State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Suzhou Nuclear Power Research Institute

Phase field simulations of phase separation in Fe-Cr binary alloys were performed by using the Cahn-Hilliard diffusion function. A new mobility model in relation to aging temperature and Cr content was used in the simulations. Two alloys of Fe-30at%Cr and Fe-35at%Cr were investigated at two different aging temperatures of 573 and 673 K. The phase separation kinetics was found to consist of three stages： wavelength modulation, amplitude increase, and coarsening of Cr-enriched regions. A higher thermal aging temperature accelerated the phase separation and increased the wavelength of concentration fluctuation. While the effect of Cr content on the phase separation kinetics was slight, Fe-Cr alloys with a higher Cr content were found to generate a larger number and a finer size of Cr-enriched regions. The simulation results provide consultation for design and safe operation of duplex stainless steel pipes in nuclear power plants.

关键词： stainless steel duplex steel phase separation kinetics nuclear power plants

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Ob ject Tracking with Dual Field-of-view Switching in Aerial Videos

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International Journal of Automation and computing 2016年第6期13卷 565-573页

作者： Yi Song shu-xiao li Cheng-Fei Zhu Hong-Xing Chang The Integrated Information System Research Center Institute of AutomationChinese Academy of Science

Visual object tracking plays an important role in intelligent aerial surveillance by unmanned aerial vehicles（UAV）. In ordinary applications, aerial videos are captured by cameras with a fixed-focus lens or a zoom lens, for which the field-of-view（FOV）of the camera is fixed or smoothly changed. In this paper, a special application of the visual tracking in aerial videos captured by the dual FOV camera is introduced, which is different from ordinary applications since the camera quickly switches its FOV during the capturing. Firstly, the tracking process with the dual FOV camera is analyzed, and a conclusion is made that the critical part for the whole process depends on the accurate tracking of the target at the moment of FOV switching. Then, a cascade mean shift tracker is proposed to deal with the target tracking under FOV switching. The tracker utilizes kernels with multiple bandwidths to execute mean shift locating, which is able to deal with the abrupt motion of the target caused by FOV switching. The target is represented by the background weighted histogram to make it well distinguished from the background, and a modification is made to the weight value in the mean shift process to accelerate the convergence of the tracker. Experimental results show that our tracker presents a good performance on both accuracy and efficiency for the tracking. To the best of our knowledge, this paper is the first attempt to apply a visual object tracking method to the situation where the FOV of the camera switches in aerial videos.

关键词： tracker camera histogram captured surveillance switching intelligent cascade Tracking quickly

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Charge noise acting on graphene double quantum dots in circuit quantum electrodynamics architecture

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Chinese Physics B 2018年第7期27卷 152-157页

作者： Yan li shu-xiao li Hai-Ou li Guang-Wei Deng Gang Cao Ming xiao Guo-Ping Guo CAS Key Laboratory of Quantum Information University of Science and Technology of ChinaHefei 230026China

We investigate the dephasing mechanisms induced by the charge noise and microwave heating effect acting on a graphene double quantum dot （DQD） capacitively coupled to a microwave resonator. The charge noise is obtained from DC transport current, and its contribution to dephasing is simultaneously determined by the amplitude response of the microwave resonator. A lowfrequency 1/f-type noise is demonstrated to be the dominant factor of the dephasing of graphene DQD. Furthermore, when the applied microwave power is larger than -90 dBm, the dephasing rate of graphene DQD increases rapidly with the increase of microwave power, and fluctuates slightly with the applied microwave power smaller than -90 dBm. Our results can be applied to suppress the impeditive influence on the dephasing of graphene-based devices associated with microwave input in the perspective investigations.

关键词： quantum dot microwave resonator charge noise graphene

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Unconventional Fluorescent and Multi-responsive Polysiloxane:Synthesis,Characterization and Biological Applications

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Chinese Journal of Polymer Science 2024年第5期42卷 579-590,I0006页

作者： xiao-Di li shu-Sheng li Xu-Bao Jiang xiao-li Zhu Xiang Zheng Kong College of Chemistry and Chemical Engineering University of JinanJinan250022China College of Chemical Engineering Tianjin UniversityTianjin300072China Foshan(Southern China)Institute for New Materials Foshan528200China

Owing to their high significance in fundamental study and diverse applications,stimuli-responsive and fluorescent polymers,particularly those with cluster-triggered emission(CTE)featured by non-conjugated chromophores,have drawn tremendous attention in recent *** this work,fluorescent and multi-responsive polysiloxane(FRPS)was synthesized by hydrolytic condensation polymerization of 3-aminopropyl methyl diethoxysilane(APMS)with 3-(N-isopropyl propionamide)iminopropyl methyl diethoxysilane(APMS-NIP),which was formed in situ through aza-Michael addition between APMS and N-isopropyl *** was not only highly sensitive to temperature,pH and CO_(2) in water,but also showed an enhanced and stimuli-adjustable fluorescence *** effects of monomer feeding,pH and CO_(2) on its lower critical solution temperature and fluorescent property were *** fluorescence emission was ascribed to CTE *** addition,FRPS was shown to be highly potential as physiological indicator for cell imaging,and for controlled release and trace detection of *** study provides therefore a type of stimuli-responsive and fluorescent material for potential applications in biomedical fields,and it is also of great significance for understanding of the fluorescence mechanism of polysiloxane-based stimuli-responsive polymers.

关键词： Polysiloxane Multi-responsiveness Cluster-triggered emission Cell imaging Controlled drug release

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我国国际卫生港创建现状及经验启示

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中国口岸科学技术 2024年第1期6卷 10-16页

作者：王晓萍徐洁李舒潇周春雅周丽萍郑伟齐润姿杭州萧山机场海关杭州311207 义乌海关义乌322001 杭州国际旅行卫生保健中心(杭州海关口岸门诊部) 杭州310061 杭州海关杭州310063

国际卫生港指经世界卫生组织认证的口岸公共卫生核心能力达标的指定口岸,是国际上通行的最高级别卫生安全口岸的代名词。本文回溯了国际卫生港建设的起源与沿革,分析当前我国国际卫生港数量、分布等现状情况,结合杭州萧山国际机场及义... 详细信息

国际卫生港指经世界卫生组织认证的口岸公共卫生核心能力达标的指定口岸,是国际上通行的最高级别卫生安全口岸的代名词。本文回溯了国际卫生港建设的起源与沿革,分析当前我国国际卫生港数量、分布等现状情况,结合杭州萧山国际机场及义乌机场成功创建国际卫生机场的经验,为下一阶段口岸创建国际卫生港工作提供借鉴与启示。目前国际卫生港在全国对外开放口岸中占比小,地区分布上存在东多西少、中部及东北地区缺失的情况,成功创建口岸类型中尚无陆路口岸。建议我国中部、东北地区口岸及一类陆路口岸加快创建进度,挖掘口岸优势与特色,注重部门间沟通协作,强化口岸核心能力,助推外向型经济和城市发展。

关键词：国际卫生港杭州萧山国际机场国际卫生机场口岸核心能力

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Quantum support vector machine for multi classification

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Communications in Theoretical Physics 2024年第7期76卷 57-62页

作者： li Xu xiao-yu Zhang Ming li shu-qian Shen College of Science China University of PetroleumQingdao 266580China

Classical machine learning algorithms seem to be totally incapable of processing tremendous data,while quantum machine learning algorithms could deal with big data unhurriedly and provide exponential acceleration over classical *** this paper,we propose two quantum support vector machine algorithms for multi *** is the quantum version of the directed acyclic graph support vector *** other one is to use the Grover search algorithm before measurement,which amplifies the amplitude of the phase storing of the classification *** k classification,the former provides quadratic reduction in computational complexity when *** latter accelerates the training speed significantly and more importantly,the classification result can be read out with a probability of at least 50%using only one *** conduct numerical simulations on two algorithms,and their classification success rates are 96%and 88.7%,respectively.

关键词： quantum support vector machine quantum feature mapping Grover search algorithm

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