Search results for "Spatial"
showing 10 items of 2121 documents
Analyse spatiale des disparités régionales dans l'Europe élargie
2004
The aim of this paper is to study the regional inequalities in the enlarged European Union using Exploratory Spatial Data Analysis applied to per capita GDP for 258 regions of EU27 over the period 1995-2000. Strong evidence in favor of global and local autocorrelation as well as spatial heterogeneity is found for the wealth distribution. We also show that the enlargement process leads to a new North-West - East polarization scheme instead of the previous results obtained in the literature highlighting a North-South polarization scheme. Implications for regional development and cohesion policies are finally explored.
Spatial effects in housing price models : do housing prices capitalize urban development policies in the agglomeration of Dijon (1999) ?
2004
In this article we suppose that the integration of accessibility and neighborhood variables in hedonic housing models doesn't allow to take into account the spatial effects between the housing prices. Using a sample of 1520 transactions of apartments in the urban area of Dijon, we focus on two types of location variables : the distance to the CBD and the distance to several Disadvantaged Districts located in peripheral areas. We detect the presence of a spatial error autocorrelation in the hedonic model indicating that the valuation of the price of an apartment is locally influenced by the prices of the neighboring apartments. Then, we estimate a spatial error model which shows that the loc…
Dispersion models and air quality data for population exposure assessment to air pollution
2014
Evaluating the extent of exposure to chemicals in absence of continuous measurements of their concentration in air and direct measures of personal exposure is crucial for epidemiological studies. Dispersion models can be a useful tool for reproducing spatio-temporal distribution of contaminants emitted by a specific source. However, they cannot easily be applied to short-term epidemiological studies because they require precise information on daily emission scenarios for a long time, which are generally not available. The aim of this study was to better assess the exposure in the industrial area of Brindisi, which suffers from various critical epidemiological situations, by integrating air …
Trends in soil mercury stock associated with pollution sources on a Mediterranean island (Majorca, Spain)
2021
8 Pág. Centro de Biotecnología y Genómica de Plantas
Distribution of Heavy Metals in Marine Sediments of Palermo Gulf (Sicily, Italy)
2008
Concentrations of Cr, Cu, Hg, Pb and Zn have been measured, by atomic absorption spectrophotometry, in the fine fraction (<63 μm) of surface sediments collected in 30 sites in the Palermo Gulf (Sicily, Italy) in order to assess the levels and the spatial distribution of these elements. Enrichment factors calculated with respect to clean areas have been considered to discriminate between levels due to background or to pollution contributions. The sampling stations, which form a grid inside these areas, are characterized by geographic proximity and by the presence of pollution sources. Ratio matching technique along with hierarchical clustering, minimum spanning tree and principal component a…
A portrait of Jost Krippendorf
2014
The problem of sustainability emerged in last decades as a result of climate change and pollution produced by modern industry to the atmosphere. Seminal studies have contributed to give alternative...
Trace metals in “Posidonia oceanica” seagrass from south-eastern Sicily
2005
Heavy-metal concentrations were measured in sediments and tissues of Posidonia oceanica seagrass from south-eastern Sicily (Italy) in order to assess the degree of metal pollution in the coastal area. Seagrasses and sediments were collected at four sites along the south-eastern coast of Sicily. Flame atomic absorption spectrophotometry (FAAS) was used to measure concentrations of Cu, Zn, Cd and Pb. Standard statistical analyses were used to assess significant differences among the levels of the elements measured in different tissues and sediment and spatial distribution. The greatest values of potentially toxic metal concentrations were observed at the station near the industrial sites of A…
Future changes in North Atlantic winter cyclones in CESM-LENS. Part I: cyclone intensity, PV anomalies and horizontal wind speed
2021
Abstract. Strong low-level winds associated with extratropical cyclones can cause substantial impacts on society. The wind intensity and the spatial distribution of wind maxima may change in a warming climate; however, the involved changes in cyclone structure and dynamics are unclear. Here, such structural changes of strong North Atlantic cyclones in a warmer climate close to the end of the current century are investigated with storm-relative composites based on Community Earth System Model Large Ensemble (CESM-LENS) simulations. Furthermore, a piecewise potential vorticity inversion is applied to associate such changes in low-level winds to changes in potential vorticity (PV) anomalies at…
A system for the real-time geo-referenced measurement of soil parameters
2011
The aim of this research is to develop a system for accurately measuring in real-time, collecting and processing a high amount of geo-referenced data of soil physical-mechanical parameters, e.g. cone penetrometer resistance, index of soil compaction, and draft force. The system for measuring the soil cone penetrometer resistance is comprised of a load cell, connected to a rod, ending with a cone, and is mounted on a frame, fixed to the front part of a tractor. The system for measuring the draft force required to till the soil is comprised of a load cell, mounted on the hitch hook of a tool carrier, towed by the tractor. Moreover, in order to test the usefulness of the system with different …
Pregnenolone sulphate improves memory processing in early-handled female rats
2013
Early life experiences lead to sex-specific behavioural and neurochemical changes in adulthood. Indeed, early handling enhances learning and memory in male rats (Cannizzaro et al., 2005), whereas it impairs learning performance in female adult rats, a finding that has been correlated to decreased nitric oxide (NO) production in the hippocampus (Noschang et al., 2010). Pregnenolone sulfate (PREGS) is considered as one of the most potent memory-enhancing neurosteroids, since its activity as a potent positive modulator of N-methyl-d-aspartate receptors (NMDARs) and a negative modulator of gamma-aminobutyric acid(A) receptors (GABA(A)Rs) (Vallée et al., 2001). Given these premises, this study a…