Remarks on entanglement entropy for gauge fields

In gauge theories the presence of constraints can obstruct expressing the global Hilbert space as a tensor product of the Hilbert spaces corresponding to degrees of freedom localized in complementary regions. In algebraic terms, this is due to the presence of a center --- a set of operators which commute with all others --- in the gauge invariant operator algebra corresponding to finite region. A unique entropy can be assigned to algebras with center, giving place to a local entropy in lattice gauge theories. However, ambiguities arise on the correspondence between algebras and regions. In particular, it is always possible to choose (in many different ways) local algebras with trivial center, and hence a genuine entanglement entropy, for any region. These choices are in correspondence with maximal trees of links on the boundary, which can be interpreted as partial gauge fixings. This interpretation entails a gauge fixing dependence of the entanglement entropy. In the continuum limit however, ambiguities in the entropy are given by terms local on the boundary of the region, in such a way relative entropy and mutual information are finite, universal, and gauge independent quantities.Comment: 26 pages, 7 figure

Design of a mechanical assembly for power kites automatic control

Wind – generated energy is one of the most relevant “clean” energies in use today – and growing -. Use of Wind Turbines is the most extended and known way to generate energy from the wind. An alternate and less known “wind generators” are the Airborne Wind Energy systems, which in essence consist in flying tethers or flying devices which are supposed to reach winds at altitudes impossible for standard or conventional wind turbines. This work consists on the design of a ground station to control and measure forces in kite tethers, as a basis / first step to develop an efficient and reliable kite flight simulator and data acquisition from real flight of a kite with onboard instruments. Further, in order to make accurate simulations and properly evaluate the possible impact of an AWE system, first thing to know are the aerodynamic coefficients. This work also aims to design a modular (and transportable) ground structure to control an AWE kite, and also to take the best measures possible by means of two cell loads connected to the control lines, which with help of the data provided by onboard equipment, would be finally used to accurately determine those coefficients.Ingeniería Mecánic

La enseñanza de la Constitución en España. Por una cultura constitucional

El trabajo hace un amplio análisis sobre los procesos normativos llevados a cabo en España, para incorporar a las enseñanzas medias el conocimiento del ordenamiento constitucional. Se estudian, a grandes rasgos, diversos antecedentes filosóficos, históricos y constitucionales de lo que pueda ser una educación política, desde la perspectiva de la complicada cultura española, muy influenciada por el hecho religioso y, sobre todo, en los tiempos modernos por la Iglesia Católica. Se valora la importancia y el significado de la educación política, recogida desde el inicio del constitucionalismo español, en la Constitución de Cádiz en 1812, explicando después el proceso evolutivo desde el franquismo y la transición hasta la aprobación de la CE vigente, cuyo 25 aniversario celebramos. Las carencias de la incorporación de la CE a la escuela han desviado el interés educativo hacia el estudio de un fenómeno clave para la consolidación del sistema democrático, como es el concepto de cultura constitucional (HABERLE, P. CRUZ). En esa línea el presente estudio se abre al campo de la sociología política y en la aproximación a dos contenidos substanciales de la cultura política: la imagen que da hoy la CE entre la ciudadanía, su arraigo en los ciudadanos/as y la valoración de las posibilidades de fortalecimiento de la cultura constitucional en aquellas áreas que exigen intervenciones democráticas, nuevas orientaciones en el proceso aplicativo de la misma CE, para evitar que no se degraden sus contenidos democráticos en su aplicación a la realidad política, que pretende ordenar normativamente

La vivienda en la construcción de la independencia energética y alimentaria familiar. / The Family dwelling in the construction of food and energy independence.

La vivienda es clave en la construcción del desarrollo sustentable y a ella suelen dirigirse las inversiones patrimoniales encargadas de fortalecer a la familia. Contemplar esta visión es fundamental para el mejoramiento de la calidad de vida dentro de un Estado que atiende más al mejoramiento de los flujos del capital que al desarrollo humano de sus pobladores. La producción y aprovechamiento tanto energético como de alimentos pueden contribuir en la independencia económica familiar otorgándoles una mayor seguridad. / Dwelling is an important key to build the sustainable development and the locus where familial investments take place to strengthen the family. It is necessary to regard this vision to ameliorate the life’s quality in a State which its objectives are the improvement of money flows more than those of the human development of its inhabitants. Energetic and feeding production in addition to its profit can contribute in the home economics independence, granting more security to the families

Cell mediated immune response of the Mediterranean sea urchin Paracentrotus lividus after PAMPs stimulation

9 páginas, 5 figuras, 1 tablaThe Mediterranean sea urchin (Paracentrotus lividus) is of great ecological and economic importance for the European aquaculture. Yet, most of the studies regarding echinoderm's immunological defense mechanisms reported so far have used the sea urchin Strongylocentrotus purpuratus as a model, and information on the immunological defense mechanisms of Paracentrotus lividus and other sea urchins, is scarce. To remedy this gap in information, in this study, flow cytometry was used to evaluate several cellular immune mechanisms, such as phagocytosis, cell cooperation, and ROS production in P. lividus coelomocytes after PAMP stimulation. Two cell populations were described. Of the two, the amoeboid-phagocytes were responsible for the phagocytosis and ROS production. Cooperation between amoeboid-phagocytes and non-adherent cells resulted in an increased phagocytic response. Stimulation with several PAMPs modified the phagocytic activity and the production of ROS. The premise that the coelomocytes were activated by the bacterial components was confirmed by the expression levels of two cell mediated immune genes: LPS-Induced TNF-alpha Factor (LITAF) and macrophage migration inhibitory factor (MIF). These results have helped us understand the cellular immune mechanisms in P. lividus and their modulation after PAMP stimulationThis work has been funded by the National Project A/026000/09AECID, 2010–2012 “Respuesta inmune de invertebrados marinos”Peer reviewe

Multiagent System Applied to the Modeling and Simulation of Pedestrian Traffic in Counterflow

An agent-based model to simulate a pedestrian crowd in a corridor is presented. Pedestrian crowd models are valuable tools to gain insight into the behavior of human crowds in both, everyday and crisis situations. The main contribution of this work is the definition of a pedestrian crowd model by applying ideas from the field of the kinetic theory of living systems on the one hand, and ideas from the field of computational agents on the other hand. Such combination supported a quantitative characterization of the performance of our agents, a neglected issue in agent-based models, through well-known kinetic parameters. Fundamental diagrams of flow and activity are presented for both, groups of homogeneous pedestrians, and groups of heterogeneous pedestrians in terms of their willingness to reach their goals.Agent-Based Modeling, Pedestrian Crowd, Activity Measurement