998 resultados para Exposición Regional Valenciana (1ª. 1909. València)


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Azomethine ylides, generated from imine-derived O-cinnamyl or O-crotonyl salicylaldeyde and α-amino acids, undergo intramolecular 1,3-dipolar cycloaddition, leading to chromene[4,3-b]pyrrolidines. Two reaction conditions are used: (a) microwave-assisted heating (200 W, 185 °C) of a neat mixture of reagents, and (b) conventional heating (170 °C) in PEG-400 as solvent. In both cases, a mixture of two epimers at the α-position of the nitrogen atom in the pyrrolidine nucleus was formed through the less energetic endo-approach (B/C ring fusion). In many cases, the formation of the stereoisomer bearing a trans-arrangement into the B/C ring fusion was observed in high proportions. Comprehensive computational and kinetic simulation studies are detailed. An analysis of the stability of transient 1,3-dipoles, followed by an assessment of the intramolecular pathways and kinetics are also reported.

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Subsidence is a hazard that may have natural or anthropogenic origin causing important economic losses. The area of Murcia city (SE Spain) has been affected by subsidence due to groundwater overexploitation since the year 1992. The main observed historical piezometric level declines occurred in the periods 1982â1984, 1992â1995 and 2004â2008 and showed a close correlation with the temporal evolution of ground displacements. Since 2008, the pressure recovery in the aquifer has led to an uplift of the ground surface that has been detected by the extensometers. In the present work an elastic hydro-mechanical finite element code has been used to compute the subsidence time series for 24 geotechnical boreholes, prescribing the measured groundwater table evolution. The achieved results have been compared with the displacements estimated through an advanced DInSAR technique and measured by the extensometers. These spatio-temporal comparisons have showed that, in spite of the limited geomechanical data available, the model has turned out to satisfactorily reproduce the subsidence phenomenon affecting Murcia City. The model will allow the prediction of future induced deformations and the consequences of any piezometric level variation in the study area.

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En las dos últimas décadas, la expresión «desarrollo territorial sostenible» se ha incorporado con éxito en los documentos de ordenación del territorio, hasta convertirse en un principio rector principal. El objetivo de este artículo es analizar la incorporación de los principios de sostenibilidad en la planificación territorial española, valorando los resultados prácticos que ello ha significado. Se ha realizado un análisis de las leyes y planes de ordenación del territorio de escala regional, destacando en cuatro casos de estudio (País Vasco, Navarra, Andalucía y Comunidad Valenciana) por la relevancia que este principio rector ha cobrado en sus procesos de planificación territorial. Se ha completado la información con la realización de entrevistas a actores clave de la ordenación del territorio en esos espacios regionales. Los resultados muestran que, a pesar de las buenas intenciones que incluyen los textos de leyes y planes, por lo común, el proceso de integración de la sostenibilidad a la planificación territorial de escala regional es lento y sus efectos prácticos todavía son escasamente visibles.

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The promotion of womenâs rights is described as a priority within the external action of the European Union (EU). As a result of the Arab Spring uprisings which have been ongoing since 2011, democracy and human rights have been pushed to the forefront of European policy towards the Euro-Mediterranean region. The EU could capitalise on these transformations to help positively reshape gender relations or it could fail to adapt. Thus, the Arab Spring can be seen to serve as a litmus test for the EUâs womenâs rights policy. This paper examines how and to what extent the EU diffuses womenâs rights in this region, by using Ian Mannersâ â˜Normative Power Europeâ as the conceptual framework. It argues that while the EU tries to behave as a normative force for womenâs empowerment by way of â˜informational diffusionâ, â˜transferenceâ â˜procedural diffusionâ and â˜overt diffusionâ; its efforts could, and should, be strengthened. There are reservations over the EUâs credibility, choice of engagement and its commitment in the face of security and ideological concerns. Moreover, it seems that the EU focuses more intently on womenâs political rights than on their social and economic freedoms.