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Patterns of grassland invasions by trees: insights from demographic and genetic spatial analyses

Journal of Plant Ecology 2015年第5期8卷 468-479页

作者： martin Dovčiak Richard Hrivnák Karol Ujházy Dušan Gömöry State University of New York College of Environmental Science and Forestry(SUNY ESF)1 Forestry DriveSyracuseNY 13210USA Institute of Botany Slovak Academy of SciencesDúbravskácesta 9Bratislava 84523Slovakia Technical University in Zvolen Faculty of ForestryT.G.Masaryka 24Zvolen 96053Slovakia

Aims Woody invasions into grasslands have increased globally due to changing land use,climate and introduced woody species,but spatial processes generating and sustaining these invasions are not well *** gain insight into the patterns of spread of tree populations within grasslands,and to propose a full spatial analytical toolbox for studying native and non-native woody spe-cies spread when long-term data are not available,we tested if 50 years of grassland invasion in Western Carpathians by Norway spruce(Picea abies Karst.)proceeded by one of the two tradi-tionally competing hypotheses of species spread:(i)by frontier expansion,or(ii)by advanced groups established ahead of the population *** also tested whether the pattern of invasion changed over *** We analyzed the spatial demographic and genetic patterns of a Norway spruce population invading a Western Carpathian grass-land using ripley’s L(t)and genetic kinship coefficients(Fij).We mapped and genotyped spruce trees across the invasion front(from the invasion leading edge to fully colonized grassland near the source population)using three demographic classes(adults,juve-niles and seedlings)to approximate the temporal aspects of the *** studied how the spatial patterns of invasion by indi-vidual demographic classes and their genetic kinship varied among adjacent plots established at different distances from the source population(ranging from 0 to 160 m,in 40-m distance increments).Important Findings Juveniles were positively genetically related to adults on fine scales(m),suggesting that adults within the grassland acted as a seed source and accelerated early ***,adults did not act as nucleation centers for the formation of advanced juvenile ***,geneti-cally unrelated juveniles formed groups independently of *** groups were small and separate at the leading edge but they increased in size and graded into a continuous zone near the source popul

关键词： genetic spatial structure mountain meadows point pattern analysis population structure secondary succession

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multi-mesh-Scale Approximation of Thin Geophysical mass Flows on Complex Topographies

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Communications in Computational Physics 2021年第1期29卷 148-185页

作者： Yih-Chin Tai Jeaniffer vides Boniface Nkonga Chih-Yu Kuo Department of Hydraulic and Ocean Engineering National Cheng Kung UniversityTainanTaiwan LEmmA R&D Services Sophia AntipolisBiotFrance&Maison de la SimulationGif-sur-YvetteFrance Universit́e Cˆote d’Azur(UCA) LJAD Nice&Inria Sophia Antipolis–ḾediterrańeeFrance Research Center for Applied Sciences Academia SinicaTaipeiTaiwan

This paper is devoted to a multi-mesh-scale approach for describing the dynamic behaviors of thin geophysical mass flows on complex *** the topographic surfaces are generally non-trivially curved,we introduce an appropriate local coordinate system for describing the flow behaviors in an efficient *** complex surfaces are supposed to be composed of a finite number of triangle *** to the unequal orientation of the triangular elements,the distinct flux directions add to the complexity of solving the Riemann problems at the boundaries of the triangular ***,a vertex-centered cell system is introduced for computing the evolution of the physical quantities,where the cell boundaries lie within the triangles and the conventional Riemann solvers can be ***,there are two mesh scales:the element scale for the local topographic mapping and the vertex-centered cell scale for the evolution of the physical *** final scheme is completed by employing the HLL-approach for computing the numerical flux at the *** numerical examples and one application to a large-scale landslide are conducted to examine the performance of the proposed approach as well as to illustrate its capability in describing the shallow flows on complex topographies.

关键词： multi-mesh-scale approach complex topography shallow flows unstructured mesh vertex-centered formulation

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Relationship of Trace Elements Concentration and Growth Rate in Alsidium triquetrum (Rhodophyta)

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American Journal of Plant Sciences 2023年第3期14卷 323-338页

作者： Arsenio J. Areces Ruben Cabrera Jhoana Díaz-Larrea Ligia Collado-vides Instituto de Geografía Tropical Ministerio de Ciencia Tecnología y Medio Ambiente Municipio Playa Ciudad Habana Cuba Gabinete de Arqueología Oficina del Historiador de la Ciudad Habana Vieja Cuba Unidad Iztapalapa Departamento de Hidrobiología Universidad Autónoma Metropolitana Ciudad de México México Department of Biological Sciences and Institute of Environment Florida International University Miami FL USA

minerals and trace elements content and concentration in marine algae vary depending on species morphology and physiology;as well as growing environmental conditions. Despite this variability, accumulation of magnesium, and especially iron, seems to be common in Chlorophyta;while Rhodophyta and Heterokontophyta show higher affinity to manganese. The red agarophyte Alsidium triquetrum was used to analyze the relationship between metal concentration, environmental conditions and growth rate. Specimens grown in situ showed a large variability of Fe, mn, mg, and Al, in thallus tissue concentrations. Further, a compelling relationship between the growth rate and the thallus concentration of mg and mn, Zn, and Al was detecte. manganese, unlike the other trace elements analyzed showed a positive linear relationship between growth rate and tissue content during the period of greatest vegetative growth.

关键词： Alsidium Growth Rate manganese Trace Elements

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母亲糖尿病、体重指数对子代出生体重及早产的影响

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中华预防医学杂志 2020年第6期54卷 650-650页

作者： Kong L Nilsson iak Gissler m 陈然(编译) 不详南京医科大学公共卫生学院

母亲妊娠前患Ⅰ型糖尿病、妊娠期糖尿病和肥胖增加了子代大于胎龄儿(LGA)和早产的风险,但胰岛素治疗的糖尿病、非胰岛素治疗的Ⅱ型糖尿病以及糖尿病与孕前体重指数(BmI)的联合效应对子代LGA和早产的影响尚不明确。本研究基于芬兰全国出... 详细信息

母亲妊娠前患Ⅰ型糖尿病、妊娠期糖尿病和肥胖增加了子代大于胎龄儿(LGA)和早产的风险,但胰岛素治疗的糖尿病、非胰岛素治疗的Ⅱ型糖尿病以及糖尿病与孕前体重指数(BmI)的联合效应对子代LGA和早产的影响尚不明确。本研究基于芬兰全国出生登记系统信息,调查了2004年1月1日至2014年12月31日期间所有活产儿信息,母亲胰岛素治疗信息从药品报销登记系统中获取、Ⅱ型糖尿病和妊娠期糖尿病诊断信息从保健登记系统中获取。

关键词：妊娠期糖尿病活产儿大于胎龄儿出生登记 Ⅱ型糖尿病 Ⅰ型糖尿病出生体重登记系统

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Artificial Intelligence Based Smart Routing in Software Defined Networks

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Computer Systems Science & Engineering 2023年第2期44卷 1279-1293页

作者： C.Aswini m.L.Valarmathi Department of Information Technology Government College of TechnologyCoimbatore641013India Department of Computer Science and Engineering Dr.Mahalingam College of Engineering and TechnologyPollachi642003India

In a non-static information exchange network,routing is an overly com-plex task to perform,which has to satisfy all the needs of the *** Deﬁned Network(SDN)is the latest and widely used technology in the future communication networks,which would provide smart routing that is visible *** various features of routing are supported by the information centric network,which minimizes the congestion in the dataﬂow in a network and pro-vides the content awareness through its mined *** to the advantages of the information centric network,the concepts of the information-centric net-work has been used in the paper to enable an optimal routing in the software-deﬁned *** there are many advantages in the information-centric network,there are some disadvantages due to the non-static communication prop-erties,which affects the routing in *** this regard,artiﬁcial intelligence meth-odology has been used in the proposed approach to solve these difﬁculties.A detailed analysis has been conducted to map the content awareness with deep learning and deep reinforcement learning with *** novel aligned internet investigation technique has been proposed to process the deep reinforcement *** performance evaluation of the proposed systems has been con-ducted among various existing approaches and results in optimal load balancing,usage of the bandwidth,and maximization in the throughput of the network.

关键词： Content aware routing software deﬁned networks deep learning load balancing

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Recent Progress in the Fabrication, Properties, and Devices of Heterostructures Based on 2D materials

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Nano-micro Letters 2019年第1期11卷 217-240页

作者： Yanping Liu Siyu Zhang Jun He Zhiming m.Wang Zongwen Liu School of Physics and Electronics Hunan Key Laboratory for Super-Microstructure and Ultrafast ProcessCentral South University State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of China School of Chemical and Biomolecular Engineering The University of Sydney

With a large number of researches being conducted on two?dimen?sional(2D) materials, their unique properties in optics, electrics, mechanics, and magnetics have attracted increasing attention. Accordingly, the idea of combining distinct functional 2D materials into heterostructures naturally emerged that pro?vides unprecedented platforms for exploring new physics that are not accessible in a single 2D material or 3D heterostructures. Along with the rapid development of controllable, scalable, and programmed synthesis techniques of high?quality 2D heterostructures, various heterostructure devices with extraordinary performance have been designed and fabricated, including tunneling transistors, photodetectors, and spintronic devices. In this review, we present a summary of the latest progresses in fabrications, properties, and applications of di erent types of 2D heterostruc?tures, followed by the discussions on present challenges and perspectives of further investigations.

关键词： Two-dimensional(2D) materials 2D heterostructures Charge and magnetotransport Electronic and optoelectronic devices

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Galerkin Finite Element Study on the Effects of Variable Thermal Conductivity and Variable mass Diffusion Conductance on Heat and mass Transfer

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Communications in Theoretical Physics 2018年第7期69卷 49-59页

作者： Imran Haider Qureshi m.Nawaz Shafia Rana T.Zubair Department of Applied mathematics and Statistics Institute of Space and TechnologyIslamabad

This article investigates the effects of variable thermal conductivity and variable mass diffusion coefficient on the transport of heat and mass in the flow of Casson fluid. Numerical simulations for two-dimensional flow induced by stretching surface are performed by using Galerkin finite element method(GFEm) with linear shape functions. After assembly process, nonlinear algebraic equations are linearized through Picard method and resulting linear system is solved iteratively using Gauss Seidal method with simulation tolerance 10^(-8). maximum value of independent variableη is searched through numerical experiments. Grid independent study was carried out and error analysis is *** results are validated by comparing with already published results. Parametric study is carried out to explore the physics of the flow. The concentration increases when mass diffusion coefficient is increased. The concentration and thermal boundary layer thicknesses increase when ?_1 and ? are increased. The effect of generative chemical reaction on concentration is opposite to the effect of destructive chemical reaction on the concentration.

关键词： variable diffusion coefficients grid independent study convergence error analysis Nusselt num-ber Casson fluid Joule heating viscous dissipation

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基于在线污泥浓度计的污泥浓缩脱水运行优化

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中国给水排水 2010年第20期26卷 146-148页

作者： m.Haeck 方闻程立 HACH LANGE GmbH Willsttterstr 美国哈希公司北京代表处北京100004

随着污泥处理与处置成本的升高,以及絮凝剂的极高成本,使得污泥浓缩优化和机械脱水优化的重要性日益显现,为生化法污水处理厂节约成本提供了可能。污泥浓缩过程可以通过在重力浓缩池中使用可悬浮颗粒物传感器实时监测污泥排放来得到改进... 详细信息

随着污泥处理与处置成本的升高,以及絮凝剂的极高成本,使得污泥浓缩优化和机械脱水优化的重要性日益显现,为生化法污水处理厂节约成本提供了可能。污泥浓缩过程可以通过在重力浓缩池中使用可悬浮颗粒物传感器实时监测污泥排放来得到改进,从而保证浓缩后的污泥都是高浓度污泥。通过监测脱水设备的进泥负荷和离心分离机中的污泥浓度可以重新制定絮凝剂的投加方案,从而减少脱水前化学处理的絮凝剂用量和费用。

关键词：运行优化污泥脱水污泥浓缩在线污泥浓度计

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Small rodent models of hepatitis B and C virus replication and pathogenesis

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微生物与感染 2012年第2期7卷 67-81页

作者： mark A.Feitelson Alla Arzumanyan marcia m.Clayton Department of Biology College of Science and TechnologyTemple University Center for Biotechnology Sbarro Health Research OrganizationDepartment of BiologyTemple University

The narrow host range of infection supporting the long-term propagation of hepatitis B and C viruses is a major limitation that has prevented a more thorough understanding of persistent infection and the pathogenesis of chronic liver disease(CLD).With hepatitis B virus(HBV),this has been partially overcome by the discovery and characterization of HBV-like viruses in wild *** hepatitis C virus(HCV),related Flaviviruses have been used as surrogate systems for such *** work has developed various mouse strains for the transplantation of human hepatocytes,which are then susceptible to infection with HBV and *** laboratories have developed transgenic mice that express virus gene products and/or support virus *** HBV transgenic mouse models develop fulminant hepatitis,acute hepatitis,or CLD following adoptive transfer,while others spontaneously develop hepatocellular carcinoma(HCC),as in human *** HCV transgenic mice,most develop no disease,but acute hepatitis has been observed in one model,while HCC appears in *** mouse models include the introduction of xenographs that replicate HBV or *** mice are not susceptible to these viruses,their ability to support virus replication and to develop liver disease characteristic of human infections,provides new opportunities to study pathogenesis and develop novel therapeutics.

关键词：肝炎病毒治疗方法临床分析肝癌

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