Geostatistical methods to map the probability of hydrogeotoxic risk by high As concentrations in groundwater. Case study in Ávila province ( Spain)

[EN] The presence of As in groundwater is a priority public health issue because it imposes serious restrictions on drinking water. Mapping probabilities of exceedance of the threshold permitted by the World Health Organization, WHO (10 μg/L) allow delimiting the most vulnerable areas. The existing geostatistical techniques are a common tool for the evaluation of these maps, though, there is no agreement on which of the methods is the best. In this study different comparison criteria are illustrated. Seven non-parametric kriging methods are used to estimate the map of probability of exceeding the As concentration the limit of 10 mg/L in groundwater at the province of Ávila. Performed validation reveals that one the best results correspond to the simplicial indicator kriging, never before compared in studies of presence of geogenic As in groundwater.[ES] La presencia de As en las aguas subterráneas es un problema prioritario de salud pública e impone serias restricciones en el agua de consumo. Los mapas de probabilidad de superar el umbral permitido por la Organización Mundial de la Salud, OMS (10 μg/L) permiten delimitar las áreas que más riesgo presentan en relación con este parámetro. Las técnicas geoestadísticas constituyen una herramienta de uso común para elaborar estos mapas, aunque lamentablemente no hay un acuerdo sobre qué técnica es la más adecuada. El presente estudio recopila distintos criterios para decidir qué método presenta resultados más robustos. Se utilizan siete métodos de kriging no paramétrico en la estimación del mapa de probabilidad de que la concentración de As en manantiales de la provincia de Ávila supere el límite de 10 μg/L. La validación revela que uno de los mejores resultados es del simplicial indicator kriging, nunca antes tenido en cuenta en estudios sobre presencia de As geogénico en aguas subterráneas.Los autores agradecen a la Obra Social de Caja de Ávila el apoyo a la investigación, al financiar el proyecto “Manantiales de la provincia de Ávila (2006-2007)” y a los revisores anónimos por los comentarios realizados.Guardiola-Albert, C.; Pardo-Igúzquiza, E.; Giménez-Forcada, E. (2017). Métodos geoestadísticos para la elaboración de mapas de probabilidad de riesgo hidrogeotóxico (HGT) por altas concentraciones de As en las aguas subterráneas. Aplicación a la distribución de HGT en la provincia de Ávila (España). Ingeniería del Agua. 21(1):71-85. doi:10.4995/ia.2017.6798.SWORD7185211Aragonés Sanz, N., Palacios Diez, M., Avello de Miguel, A., Gómez Rodríguez, P., Martínez Cortés, M., Rodríguez Bernabeu, M.J. 2001. 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Nonequilibrium phase transition in a model for the propagation of innovations among economic agents

We characterize the different morphological phases that occur in a simple one-dimensional model of propagation of innovations among economic agents [X.\ Guardiola, {\it et. al.}, Phys. Rev E {\bf 66}, 026121 (2002)]. We show that the model can be regarded as a nonequilibrium surface growth model. This allows us to demonstrate the presence of a continuous roughening transition between a flat (system size independent fluctuations) and a rough phase (system size dependent fluctuations). Finite-size scaling studies at the transition strongly suggest that the dynamic critical transition does not belong to directed percolation and, in fact, critical exponents do not seem to fit in any of the known universality classes of nonequilibrium phase transitions. Finally, we present an explanation for the occurrence of the roughening transition and argue that avalanche driven dynamics is responsible for the novel critical behavior

Twenty-year advanced DInSAR analysis of severe land subsidence: The Alto Guadalentin Basin (Spain) case study

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Competitive Targeted Marketing

In this paper, we consider two firms diffusing incompatible technologies and their decision of consumer targeting. The technology adoption is made in two steps. First, once the firms sell their products to their respective targeted consumer, the technology is diffused successively by word-of-mouth communication from the initial consumer to other consumers linked along the network. Then, in the second step, each consumer imitates the technology the neighbors use which fares better, and through this process of imitation, the technology distribution keeps evolving until it reaches the long-run steady state. We demonstrate that the early entrant chooses the minmax location when firms are myopic in the sense that they do not take the imitation possibility into account. If firms consider the possibility of imitation, the best target will tend towards a hub, although the minmax principle in general keeps valid in the sense that it should be the minmax location after considering imitation

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Anti-tumour necrosis factor discontinuation in inflammatory bowel disease patients in remission: study protocol of a prospective, multicentre, randomized clinical trial

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