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A procedure to assess the spatial variability in the importance of abiotic factors affecting distributions： the case of world freshwater fishes

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Current Zoology 2018年第5期64卷 549-557页

作者： Ana M. MANJARRES-HERNANDEZ Castor GUISANDE Emilio GARCiA-ROSELLO Patricia PELAYO-VILLAMIL jacinto gonzalez-dacosta Juirgen HEINE Luis gonzalez VILAS Carlos GRANADO-LORENClO Santiago R. DUQUE Jorge M. LOBO alnstituto Amazonico de Investigaciones-IMANI Universidad Nacional de Colombia Leticia A.A. 215 Colombia 910001 Facultad de Ciencias del Mar Universidad de Vigo Vigo 36310 Spain Departamento de Informatica Edificio Fundicien Universidad de Vigo Vigo 36310 Spain Grupo de Iciologia Universidad de Antioquia Medellin Colombia 050010 eDepartamento de Biologia Vegetal y Ecologia Facultad de Biologia Universidad de Sevilla Sevilla 41080 Spain Departamento de Biogeografia y Cambio Global Museo Nacional de Ciencias Naturales (CSIC) Calle de Jose Gutierrez Abascal 2 Madrid 28006 Spain

Understanding the factors shaping species＇ distributions is a key longstanding topic in ecology with unresolved issues. The aims were to test whether the relative contribution of abiotic factors that set the geographical range of freshwater fish species may vary spatially and/or may depend on the geographical extent that is being considered. The relative contribution of factors, to discriminate between the conditions prevailing in the area where the species is present and those existing in the considered extent, was estimated with the instability index included in the R pack- age SPEDInstabR. We used 3 different extent sizes： 1） each river basin where the species is present （local）; 2） all river basins where the species is present （regional）; and 3） the whole Earth （global）. We used a data set of 16,543 freshwater fish species with a total of 845,764 geographical records, together with bioclimatic and topographic variables. Factors associated with tempera- ture and altitude show the highest relative contribution to explain the distribution of freshwater fishes at the smaller considered extent. Altitude and a mix of factors associated with temperature and precipitation were more important when using the regional extent. Factors associated with precipitation show the highest contribution when using the global extent. There was also spatial variability in the importance of factors, both between species and within species and from region to region. Factors associated with precipitation show a clear latitudinal trend of decreasing in importance toward the equator.

关键词： anisotropic predictors environmental data selection geographical background non-stationary predictors

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Small-signal Model for Dual-active-bridge Converter Considering Total Elimination of Reactive Current

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Journal of Modern Power Systems and Clean Energy 2021年第2期9卷 450-458页

作者： Juan Ramon Rodriguez-Rodriguez Nadia Maria Salgado-Herrera jacinto Torres-Jimenez Nestor gonzalez-Cabrera David Granados-Lieberman Martin Valtierra-Rodriguez the Universidad Nacional Autonoma de Mexico Facultad de IngenieriaDepto.Energia Electri-ca.Av.Universidad 3000Col.UNAM CUCoyoacanCDMXMexico the Instituto de Energias Renovables Universidad Nacional Autonoma de MexicoPriv.Xochicalco s/nCol.Centro.TemixcoMorelosMexico the Instituto Tec-nologico Superior de Irapuato Carretera Irapuato-Silao km 12.5.IrapuatoGuanajuatoMexico the Universidad Autonoma de Queretaro Campus San Juan del RioRio Moctezuma 249San Juan del RioQueretaroMexico

Emerging technologies such as electric vehicles,solid-state transformers,and DC transformers are implemented using the closed-loop bi-directional dual-active-bridge(DAB)*** this context,it is necessary to have average models that provide an efficient way of tuning the proportional integral(PI)compensator parameters for large-and small-signal *** present a novel small-signal model(SSM)for DAB converter with a single closed-loop PI controller and the total elimination of reactive current(IQ=0).The method applies a modulation technique for IQ=0 and introduces a composite function in the controller while reducing the original nonlinear switching model,which allows to decrease the order of the transfer function and analyze the closed-loop *** proposed SSM is analyzed using different response time,load,and DC voltage *** simulation and experimental results demonstrate the ease of implementation and effectiveness of the proposed model with respect to other SSM techniques.

关键词： Small-signal model(SSM) dual-active-bridge(DAB)converter reactive current elimination proportional integral(PI)control

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1.3 μm emitting SrF2：Nd^3＋ nanoparticles for high contrast in vivo imaging in the second biological window

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Nano Research 2015年第2期8卷 649-665页

作者： Irene Villa Anna Vedda Irene Xochilt Cantarelli Marco Pedroni Fabio Piccinelli Marco Bettinelli Adolfo Speghini Marta Quintanilla Fiorenzo Vetrone Ueslen Rocha Carlos jacinto Elisa Carrasco Francisco Sanz Rodrfguez Angeles Juarranz Blanca del Rosal Dirk H. Ortgies Patricia Haro gonzalez Jose Garcia Sole Daniel Jaque Garcia Department of Materials Science University of Milano-Bicocca Via R. Cozzi 55 20125 Milano Italy Dipartimento di Biotecnologie Universita di Verona and INSTM UdR Verona Strada le Grazie 15 37134 Verona Italy Institut National de la Recherche Scientifique-Energie Materiaux et Telecommunications Universitd du Quebec Varennes QC PQ J3X 1S2 Canada Grupo de Fotonica e Fluidos Complexos Instituto de Fisica Universidade Federal de Alagoas 57072-970 Maceio Alagoas Brazil Departamento de Biologia Facultad de Ciencias Campus de Cantoblanco Universidad Autdnoma de Madrid Madrid 28049 Spain Fluorescence Imaging Group Departamento de Fisica de Maferiales Facultad de Ciencias Campus de Cantoblanco Universidad Aut6noma de Madrid Madrid 28049 Spain

Novel approaches for high contrast, deep tissue, in vivo fluorescence biomedical imaging are based on infrared-emitting nanoparticles working in the so-called second biological window （1,000-1,400 nm）. This allows for the acquisition of high resolution, deep tissue images due to the partial transparency of tissues in this particular spectral range. In addition, the optical excitation with low energy （infrared） photons also leads to a drastic reduction in the contribution of autofluorescence to the in vivo image. Nevertheless, as is demonstrated here, working solely in this biological window does not ensure a complete removal of autofluorescence as the specimens diet shows a remarkable infrared fluorescence that extends up to 1,100 nm. In this work, we show how the 1,340 nm emission band of Nd3. ions embedded in SrF2 nanoparticles can be used to produce autofluorescence free, high contrast in vivo fluorescence images. It is also dem- onstrated that the complete removal of the food-related infrared autofluorescence is imperative for the development of reliable biodistribution studies.

关键词： fluorescence imaging rare earth dopednanoparticles nanomedicine

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Diversity Dimensions of Freshwater Fish Species around the World

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Journal of Geographic Information System 2021年第1期13卷 1-18页

作者： Carlos Granado-Lorencio Cástor Guisande Patricia Pelayo-Villamil Ana Manjarrés-Hernández Emilio García-Roselló Juergen Heine Elisa Pérez-Costas Luis González-Vilas jacinto González-dacosta Jorge M. Lobo Departamento de Biología Vegetal y Ecología Facultad de Biología Universidad de Sevilla Seville Spain Facultad de Ciencias del Mar Universidad de Vigo Campus Lagoas-Marcosende Vigo Spain Grupo de Ictiología Universidad de Antioquia Medellín Colombia Instituto Amazónico de Investigaciones (IMANI) Universidad Nacional de Colombia Leticia Colombia Department of Computer Science Universidad de Vigo Campus Lagoas-Marcosende Vigo Spain Departamento de Biogeografía y Cambio Global Museo Nacional de Ciencias Naturales (CSIC) Madrid Spain

The quality and coverage of the available taxonomical and geographical information and the recognition that diversity is multi-faceted are two main factors that hinder to understand the spatial and temporal variations of biodiversity. In this study, we aim to quantify the global distribution of five diversity components used to assess freshwater fish diversity in river basins around the world. The multidimensional character of these diversity components was estimated and the so obtained diversity dimensions mapped. This was done taking into account those well-surveyed basins discriminated by considering collector’s curves, and additionally by controlling for the effect of survey effort on all considered diversity components. A total of 1,472,109 occurrence records were analysed, corresponding to 17,292 species of freshwater fishes. Five diversity components were considered: functional richness, species richness, taxonomic diversity, and two rarity measures. Well-surveyed river basins were discriminated using accumulation curves. The effects of survey biases and knowledge gaps were minimized by determining the relationship of each component with the completeness values calculated for each river basin. The geographical pattern derived from raw data is skewed by the unequal knowledge available, and all diversity components were positively correlated with completeness values. The first dimension described the association between species richness and functional diversity. The second dimension represented rarity and taxonomic diversity. The congruence between species richness and functional diversity suggests that ecosystem functions increase with the number of fish species present in river basins and that a decrease in species richness may involve a loss of functionality. The levels of rarity and taxonomic diversity of many species-poor basins found in arid and cold regions suggest that the distinctiveness of their freshwater fishes is primarily a consequence of how isol

关键词： Diversity Components Functional Diversity Species Richness Rarity Taxonomic Diversity

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