Search results for "SPATIAL STRUCTURE"
showing 10 items of 30 documents
Age and spatial structure of natural Pinus sylvestris stands in Latvia
2005
Abstract The age and spatial structure of six natural old growth Pinus sylvestris stands in Latvia were investigated, to attempt to identify retrospectively the past features of development. In each stand, one or two plots of size 200–900 m2 were established. Tree locations were mapped, stem diameter was measured, and tree age was determined from cores or by counting branch whorls. Tree distribution was assessed by Ripley's K function. A clumped spatial pattern was shown for P. sylvestris younger than 100 years. The temporal patterns of establishment could be partly linked to favourable climatic periods. The major disturbance affecting pine stands along the coast was windblown sand, which p…
FUNCIONES NEUROPSICOLÓGICAS EN LAS HABILIDADES DE INICIO A LA LECTOESCRITURA
2016
Abstract:Numerous studies have tried to identify the set of skills and knowledge that are the basis for the development of literacy as phonological awareness, orthographic awareness and RAN. Since learning of literacy has its onset between 3 and 6 years, which is the maximum period of brain plasticity, it is clear the need to relate certain brain functions with the early onset of the skills that are the basis of its learning. Thus, the main objective of this work is the detection of neuropsychological functions that allow proper development of all those skills. Participants were 119 students who have been assessed twice, when 4 and 5 years old. The instruments used were the BIL, the Rapid A…
Changes in the Spatial Structure of the Landscape of Isolated Forest Complexes in the 19th and 20th Centuries and Their Potential Effects on Supporti…
2020
This study assesses the changes in the spatial structure of the landscape between 1825 and 2019 in the isolated, protected forest complex of the Niemodlin Forests. Based on the analysis of changes in this structure, a change the supporting ecosystem services related to the protection of biodiversity was proposed. The landscape metrics were used separately for the analysis of the structure of the whole landscape, and individual types of ecosystems were used in the research. There were no major changes in the share of individual types of ecosystems during the period under review. At the same time, a very large increase in built-up areas and tree stands was found in 1825. Landscape metrics poi…
Fractal dimension versus density of built-up surfaces in the periphery of Brussels
2007
International audience; This paper aims at showing the usefulness of the fractal dimension for characterizing the spatial structure of the built-up surfaces within the periurban fringe. We first discuss our methodology and expectations in terms of operationality of the fractal dimension theoretically and geometrically. An empirical analysis is then performed on the southern periphery of Brussels (Brabant Wallon). The empirical analysis is divided into two parts: first, the effect of the size and shape of the windows on the fractal measures is empirically evaluated; this leads to a methodological discussion about the importance of the scale of analysis as well as the real sense of fractality…
Spatial distribution of the arctic haze aerosol size distribution in western and eastern Arctic
1997
Abstract Since June 1993, four flight campaigns to the Arctic have been carried out by a group of scientists from Russia and Germany. Optical remote-sensing methods and in-situ chemical and aerosol measurements have been combined on board a Russian IL-18 research aircraft. From arctic air bases in Siberia, Alaska, Canada, and Spitsbergen, respectively, flights have been undertaken to determine spatial structure of arctic haze events. This paper reports on aerosol data obtained during the expedition of Spring 1994. Haze events have been found in the east and west Arctic, containing about the same concentration of particles. Horizontal and vertical layer extensions are given and the size dist…
Spatial Bayesian Modeling Applied to the Surveys of Xylella fastidiosa in Alicante (Spain) and Apulia (Italy)
2020
The plant-pathogenic bacterium Xylella fastidiosa was first reported in Europe in 2013, in the province of Lecce, Italy, where extensive areas were affected by the olive quick decline syndrome, caused by the subsp. pauca. In Alicante, Spain, almond leaf scorch, caused by X. fastidiosa subsp. multiplex, was detected in 2017. The effects of climatic and spatial factors on the geographic distribution of X. fastidiosa in these two infested regions in Europe were studied. The presence/absence data of X. fastidiosa in the official surveys were analyzed using Bayesian hierarchical models through the integrated nested Laplace approximation (INLA) methodology. Climatic covariates were obtained from …
Hepatitis B core particles as a universal display model: a structure-function basis for development
1999
AbstractBecause it exhibits a remarkable capability to accept mutational intervention and undergo correct folding and self-assembly in all viable prokaryotic and eukaryotic expression systems, hepatitis B core (HBc) protein has been favored over other proposed particulate carriers. Structurally, the unusual α-helical organization of HBc dimeric units allows introduction of foreign peptide sequences into several areas of HBc shells, including their most protruding spikes. Progress toward full resolution of the spatial structure as well as accumulation of chimeric HBc-based structures has brought closer the knowledge-based design of future vaccines, gene therapy tools and other artificial par…
Urban segregation and unemployment: A case study of the urban area of Marseille – Aix-en-Provence (France)
2018
International audience; In this paper, we study the effects of the spatial organization of the urban area of Marseille – Aix-en-Provence on unemployment there. More specifically, differences in the characteristics of the residential population induce urban stratification with the result that urban structure may affect the probability of employment. In order to evaluate the effects of spatial structure on unemployment, we implement a spatial probit model to reveal the employment probabilities of young adults still living with their parents. Our results support the hypothesis that living in or near a deprived neighborhood decreases the probability of employment.
Cambios en la frecuencia de los Regímenes de Tiempo sobre la región Euro-Atlántica y Mediterránea y su relación con las temperaturas anómalas sobre e…
2014
An exercise has been carried out to assess to what extent the Euro-Atlantic Weather Regimes (WR), described from the ERA-interim Reanalysis in the summer season, projects onto a pool of AGCMAMIP simulations in which sea surface temperatures (SST) are prescribed from observations. Although the model simulations present some biases in the spatial structure and seasonality of WRs, exhibiting also less variability, they are able to capture main WR over the region in summer season: +Middle East –Middle East, +NAO, -NAO. WR paradigm is used to quantify changes in the atmosphere under warmer/colder than normal conditions over the Mediterranean Sea. To address this problem, firstly, changes in the …
Spatio-temporal Vegetation Recuperation after a Grassland Fire in Lithuania
2013
The aim of this work is to study the spatio-temporal effects of a grassland fire in Lithuania. Immediately after the fire, a experimental plot was designed in a east-faced slope. Vegetation cover and height were measured 10, 17, 31 and 46 days after the fire (vegetation cover was only measured until 31 days after the fire because in the last measurement campaign the plot was completely covered). The results showed that vegetation recovered very fast. Ten days after the fire vegetation cover and height distribution were heterogeneous, decreasing with the time due to vegetation spread. Vegetation recovered was specially observed between 17 and 31 days after the fire due vegetation recuperatio…