22 research outputs found

    Spatial surface-pattern analyses and boundary detection techniques applied in forest ecology

    Get PDF
    [EN] We review methods for uni- and multivariate surface pattern analysis and boundary detection used in forest ecology. A continuous surface pattern is defined as the locations of points (trees) in the space and the associated variable or variables. We illustrate useful methods to describe spatial patterns and infer the generating processes. We show the statistical basis and applied examples of univariate methods for binary (join counts) and quantitative variables (Moran and Geary correlograms, semivariograms, fractal dimension). We explain the calculus and interpretation of multivariate methods to describe surface patterns (Mantel test and correlogram) and their relationships with ordination methods. Finally, we show examples of techniques for boundary detection. Most analysed patterns corresponded to Pinus uncinata forests from the upper altitudinal limit in the Pyrenees or from a relict population. We discuss the advantages and disadvantages of each methodology and their applications in forest ecology.[ES] En este trabajo se revisan los métodos de análisis univariable y multivariable de los patrones de superficies y de detección de fronteras más utilizados en ecología forestal. El patrón de superficies es un patrón espacial continuo definido por las posiciones de los puntos (árboles) en el espacio y una o varias variables asociadas a cada punto. Se ilustran métodos útiles para describir patrones espaciales e inferir los procesos que los generaron. Se muestra el fundamento estadístico y ejemplos aplicados de métodos de análisis univariables para variables binarias (conteo contiguo) y cuantitativas (correlogramas de Moran y Geary, semivariogramas, dimensión fractal). Se detalla el cálculo e interpretación de métodos multivariables para la descripción de patrones de superficies (correlograma y test de Mantel) y su relación con los métodos de ordenación. Finalmente, se muestran ejemplos de métodos para la detección de fronteras. La mayor parte de los patrones reales analizados provienen de bosques de Pinus uncinata del límite altitudinal superior en los Pirineos o bien de una población relíctica. Se discuten las ventajas y desventajas de cada metodología y sus aplicaciones en ecología forestal.Los datos de Vinuesa se obtuvieron en el proyecto AMB95-0160 (CICyT).Peer reviewe

    Система управления персоналом в Управлении железнодорожного транспорта Алмалыкского Горно-Металлургического комбината

    Get PDF
    Целью выпускной квалификационной работы является разработка направлений по совершенствованию системы управления персоналом в управлении железнодорожного транспорта АО "АГМК". В результате исследования были разработаны мероприятия по повышению уровня управления персоналом в управлении железнодорожного транспорта АО "АГМК" Степень внедрения: одно из разработанных предложений планируется на внедрение в управлении персоналом железнодорожного транспорта АО "АГМК". Область применения: разработанные мероприятия по управлению персоналом предприятия, может быть использован на предприятии, в организации, фирме любой отрасли.Научная новизна работы заключается в обосновании необходимости формирования новой концепции управления персоналом на предприятии, в обобщении основных методов управления персонThe goal of the final qualifying work is to develop directions for improving the personnel management system in the management of the railway transport of JSC "AGMK". As a result of the research, measures were developed to improve the level of personnel management in the management of the railway transport of JSC "AGMK" Degree of implementation: one of the developed proposals is planned for implementation in the management of railway transport personnel of JSC "AGMK". Scope: developed measures for the management of the company's personnel, can be used at the enterprise, in the organization, the firm of any industry. The scientific novelty of the work is to justify the need to formulate a new concept of personnel management at the enterprise, to generalize the basic methods of personnel ma

    Die Stoffwechselwirkungen der Schilddrüsenhormone

    Get PDF

    Chemischer Beitrag zur Frage der Herzmuskelschädigung durch Thyroxin

    No full text

    Endothelial versus pronephron fate decision is modulated by the transcription factors Cloche/Npas4l, Tal1, and Lmo2

    No full text
    Endothelial specification is a key event during embryogenesis; however, when, and how, endothelial cells separate from other lineages is poorly understood. In zebrafish, Npas4l is indispensable for endothelial specification by inducing the expression of the transcription factor genes etsrp, tall, and Imo2. We generated a knock-in reporter in zebrafish npas4l to visualize endothelial progenitors and their derivatives in wild-type and mutant embryos. Unexpectedly, we find that in npas4l mutants, npas4l reporter-expressing cells contribute to the pronephron tubules. Single-cell transcriptomics and live imaging of the early lateral plate mesoderm in wild-type embryos indeed reveals coexpression of endothelial and pronephron markers, a finding confirmed by creERT2-based lineage tracing. Increased contribution of npas4l reporter-expressing cells to pronephron tubules is also observed in tall and Imo2 mutants and is reversed in npas4l mutants injected with tall mRNA. Together, these data reveal that Npas4l/Tal1/Lmo2 regulate the fate decision between the endothelial and pronephron lineages

    Conserved and context-dependent roles for pdgfrb signaling during zebrafish vascular mural cell development

    No full text
    Platelet derived growth factor beta and its receptor, Pdgfrb, play essential roles in the development of vascular mural cells, including pericytes and vascular smooth muscle cells. To determine if this role was conserved in zebrafish, we analyzed pdgfb and pdgfrb mutant lines. Similar to mouse, pdgfb and pdgfrb mutant zebrafish lack brain pericytes and exhibit anatomically selective loss of vascular smooth muscle coverage. Despite these defects, pdgfrb mutant zebrafish did not otherwise exhibit circulatory defects at larval stages. However, beginning at juvenile stages, we observed severe cranial hemorrhage and vessel dilation associated with loss of pericytes and vascular smooth muscle cells in pdgfrb mutants. Similar to mouse, pdgfrb mutant zebrafish also displayed structural defects in the glomerulus, but normal development of hepatic stellate cells. We also noted defective mural cell investment on coronary vessels with concomitant defects in their development. Together, our studies support a conserved requirement for Pdgfrb signaling in mural cells. In addition, these zebrafish mutants provide an important model for definitive investigation of mural cells during early embryonic stages without confounding secondary effects from circulatory defects
    corecore