20 resultados para DIFFERENT PHASES


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El litoral ha constituido a lo largo de la historia una importante fuente de recursos económicos además de un punto estratégico para la defensa del territorio. El comercio, la pesca o la industria de la sal han propiciado la formación de poblaciones y ciudades al borde del mar. La costa funcionó como un ámbito defensivo, peligroso e insalubre durante siglos donde el mar modulaba el frente costero sin grandes interacciones con un entorno prácticamente deshabitado. A mediados del siglo XIX, las innovaciones técnicas y la pacificación definitiva del Mediterráneo permiten poner en valor sus características naturales y de oportunidad. Sin perder del todo su valor defensivo, el litoral resurge como recurso productivo y como lugar de ocio y disfrute de la población. El valor estratégico de la costa quedará también reflejado en el marco normativo. El derecho civil moderno recuperará el concepto de Dominio público Marítimo Terrestre a través de la Ley de Aguas de 1866 que regulará también los usos y las limitaciones en la propiedad privada litoral. Desde ese momento, las transformaciones económicas, sociales, jurídicas y ambientales van a provocar un cambio significativo en la relación entre la sociedad y la costa que dará paso a la construcción del espacio litoral que hemos heredado. Desde la triple perspectiva del litoral como sistema físico ambiental, sistema económico, productivo y cultural, y sistema administrativo y legal, el principal objetivo de la tesis será reconstruir el proceso de transformación del litoral consecuencia de la evolución en la forma de producción del espacio, de área defensiva a recurso productivo, y desde mediados del siglo XIX hasta principios del siglo XXI. Sin embargo, la construcción del litoral no ha sido homogénea ni constante a lo largo del tiempo. Ha estado sujeta a los distintos vaivenes económicos y sociales pero también a los cambios en el modelo territorial definido por el marco legal vigente, así como a los reajustes del propio sistema físico. Como instrumento sociopolítico, el marco legal regula las presiones del sistema económico sobre el medio, apostando por una visión frente a otra, y posibilitando el grado de transformación final. Así, el conocimiento sobre el territorio en el que se interviene y la definición del modelo de litoral por parte de los poderes públicos irán configurando el espacio físico, económico y social desarrollado en la costa. Para la reconstrucción del proceso de construcción del litoral, la tesis define cuatro fases diferentes y aplica las hipótesis y la metodología a la costa de Cartagena. Se presenta gráficamente la evolución en los tres sistemas en cada una de las fases, y se recompone el relato histórico a través de los hitos más relevantes para el proceso. En cada una de las fases, el nuevo modelo intentará dar respuesta a todo aquello que no funcionó o se quedó a medias en el periodo anterior. Las crisis económicas provocan la ralentización de la actividad productiva y, consecuentemente, de las transformaciones en el territorio. Servirán para establecer, en principio, un cambio de paradigma en la lectura y gestión del litoral que acabará traduciéndose en un nuevo texto legislativo en materia de costas (1969, 1988 y 2013). La reforma de la normativa responde a una nueva forma de entender, ordenar, gestionar e intervenir en el territorio, donde se modulan las pautas pero también la intensidad en la intervención. Pero nace condicionada por el litoral heredado: los derechos generados durante la vigencia del marco legal anterior; el modelo económico y sus presiones y expectativas sobre el litoral; y el medio físico en el que se acumulan los procesos de degradación no resueltos y los nuevos riesgos. Así, las conclusiones de la tesis ponen de manifiesto la necesidad de una visión compleja e integral sobre el litoral, en la que el urbanismo y la ordenación del territorio serán fundamentales para afrontar los nuevos retos en su construcción a futuro. ABSTRACT The littoral has been throughout history an important source of economic resources and a strategic point for the defense of territory. Trade, fishing or salt industry have led to the formation of towns and cities on the edge of the sea. The coast served as a defensive, dangerous and unhealthy place where the sea modulated for centuries the waterfront without major interactions with a virtually uninhabited environment. In the mid-nineteenth century, technical innovations and the final pacification of the Mediterranean allowed to value its natural features and opportunities. Without entirely losing its defensive value, the coast emerges as a productive resource and as a place of leisure and enjoyment of people. The strategic value of the coast will also be reflected in the legal framework. The concept of maritime-terrestrial public domain will be recovered by the modern civil law and the law of waters of 1866 governs the uses and limitations of private ownership of the coast. Since then, the economic, social, legal and environmental changes will to cause a significant change in the relationship between society and the coast that will give way to the construction of littoral space inherited. From the triple perspective of the littoral as a physical environmental system, an economic, productive and cultural system, and an administrative and legal system, the main objective of the thesis is to rebuild its process of transformation, as a result of the evolution in the way that space is produced, from defensive zone to productive resource, and from the middle of the nineteenth century until the beginning of the twenty-first century. However, the construction of the coast has not been uniform nor constant over time. It has been subject to different economic and social fluctuations and also to changes in the territorial model defined by the legal framework in force, as well as to readjustments of the physical system itself. As socio-political instrument, the legal framework regulates the pressure of the economic system on the environment, it bets on a vision over another and facilitates the final degree of transformation. Thus, the knowledge on the territory that is being intervened and the definition of the model of shoreline by public authorities will configure the physical, economic and social space developed on the coast. For the reconstruction of the littoral building process, the thesis defines four different phases and applies the hypothesis and methodology to the coast of Cartagena. It introduces graphically the evolution of the three systems in each of the phases and it recomposes the historical account through of the most important milestones for the process. In each phase, the new model will attempt to answer everything that did not work or was half in the previous period. Economic crises cause a slowdown in productive activity and, consequently, in the changes of territory. They serve to establish, in principle, a paradigm shift for reading and managing the littoral, eventually resulting in new legal texts on coasts matter (1969, 1988 and 2013). The reform of legislation responds to a new way for understanding, arranging, managing and intervening on the territory, where the guidelines and also the intervention intensity are modulated. But it is born conditioned by the inherited coast: the rights generated under previous legal framework; the economic model and its pressures and expectations on the littoral; and the physical environment which accumulates degradation processes unresolved and new risks. Thus, the thesis conclusions highlight the need for a complex and comprehensive view on the littoral, where urban planning and land-use planning will be key to meet the future challenges in its construction.

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By using the spray pyrolysis methodology in its classical configuration we have grown self-assembled MgxZn1−xO quantum dots (size [similar]4–6 nm) in the overall range of compositions 0 ≤ x ≤ 1 on c-sapphire, Si (100) and quartz substrates. Composition of the quantum dots was determined by means of transmission electron microscopy-energy dispersive X-ray analysis (TEM-EDAX) and X-ray photoelectron spectroscopy. Selected area electron diffraction reveals the growth of single phase hexagonal MgxZn1−xO quantum dots with composition 0 ≤ x ≤ 0.32 by using a nominal concentration of Mg in the range 0 to 45%. Onset of Mg concentration about 50% (nominal) forces the hexagonal lattice to undergo a phase transition from hexagonal to a cubic structure which resulted in the growth of hexagonal and cubic phases of MgxZn1−xO in the intermediate range of Mg concentrations 50 to 85% (0.39 ≤ x ≤ 0.77), whereas higher nominal concentration of Mg ≥ 90% (0.81 ≤ x ≤ 1) leads to the growth of single phase cubic MgxZn1−xO quantum dots. High resolution transmission electron microscopy and fast Fourier transform confirm the results and show clearly distinguishable hexagonal and cubic crystal structures of the respective quantum dots. A difference of 0.24 eV was detected between the core levels (Zn 2p and Mg 1s) measured in quantum dots with hexagonal and cubic structures by X-ray photoemission. The shift of these core levels can be explained in the frame of the different coordination of cations in the hexagonal and cubic configurations. Finally, the optical absorption measurements performed on single phase hexagonal MgxZn1−xO QDs exhibited a clear shift in optical energy gap on increasing the Mg concentration from 0 to 40%, which is explained as an effect of substitution of Zn2+ by Mg2+ in the ZnO lattice.

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Two sheep and two goats, fitted with a ruminal cannula, received two diets composed of 30% concentrate and 70% of either alfalfa hay (AL) or grass hay (GR) as forage in a two-period crossover design. Solid and liquid phases of the rumen were sampled from each animal immediately before feeding and 4 h post-feeding. Pellets containing solid associated bacteria (SAB) and liquid associated bacteria (LAB) were isolated from the corresponding ruminal phase and composited by time to obtain 2 pellets per animal (one SAB and one LAB) before DNA extraction. Denaturing gradient gel electrophoresis (DGGE) analysis of 16S ribosomal DNA was used to analyze bacterial diversity. A total of 78 and 77 bands were detected in the DGGE gel from sheep and goats samples, respectively. There were 18 bands only found in the pellets from sheep fed AL-fed sheep and 7 found exclusively in samples from sheep fed the GR diet. In goats, 21 bands were found only in animals fed the AL diet and 17 were found exclusively in GR-fed ones. In all animals, feeding AL diet tended (P < 0.10) to promote greater NB and SI in LAB and SAB pellets compared with the GR diet. The dendrogram generated by the cluster analysis showed that in both animal species all samples can be included in two major clusters. The four SAB pellets within each animal species clustered together and the four LAB pellets grouped in a different cluster. Moreover, SAB and LAB clusters contained two clear subclusters according to forage type. Results show that in all animals bacterial diversity was more markedly affected by the ruminal phase (solid vs. liquid) than by the type of forage in the diet.

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The aim of the present study was to identify the importance of floorball tactical variables to predict ball possession effectiveness, when controlling quality of opposition and game periods. The sample was composed by 1500 ball possessions, corresponding to 14 games randomly selected from the International Championships played during 2008 and 2010 (World Championship, Four nations tournament and classificatory phases for World Championship) by teams from different competition levels (HIGH, INTERMEDIATE and LOW). The effects of the predictor variables on successful ball possessions according to the three game contexts (HIGH vs. HIGH; HIGH vs. LOW; LOW vs. LOW games) were analyzed using Binomial Logistic Regressions. The results showed no interaction with the game period. In HIGH vs. HIGH games, quality of opposition showed an association with ball possession effectiveness with ending zone, offensive system, possession duration, height of shooting and defensive pressures previous to the shot. In HIGH vs. LOW games the important factors were the starting zone, possession duration, defensive pressure previous to the last pass and to the shot, technique of shooting and the number players involved in each ball possession. Finally, in LOW vs. LOW games, the results emphasized the importance of starting and ending zones, the number of passes used and the technique of shooting. In conclusion, elite floorball performance is mainly affected by quality of opposition showing different game patterns in each context that should be considered by coaches when preparing practices and competitions.

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The aim of this study was to investigate the effects of different swimming race constraints on the evolution of turn parameters. One hundred and fifty-eight national and regional level 200-m (meters) male swimming performances were video-analyzed using the individualized-distance model in the Open Comunidad de Madrid tournament. Turn (p < .001, ES = 0.36) and underwater distances (p < .001, ES = 0.38) as well as turn velocity (p < .001, ES = 0.69) significantly dropped throughout the race, although stroke velocity and underwater velocity were maintained in the last lap of the race (p > .05). Higher expertise swimmers obtained faster average velocities and longer distances in all the turn phases (p < .001, ES = 0.59), except the approach distance. In addition, national level swimmers showed the ability to maintain most of the turn parameters throughout the race, which assisted them in improving average velocity at the end of races. Therefore, the variations in the turning movements of a swimming race were expertise-related and focused on optimizing average velocity. Turning skills should be included in the swimming race action plan.