The devil in the comedies of Félix Lope de Vega

Thesis (M.A.)--Boston Universit

Solving structural optimization problems with genetic algorithms and simulated annealing

In this paper we study the performance of two stochastic search methods: Genetic Algorithms and Simulated Annealing, applied to the optimization of pin‐jointed steel bar structures. We show that it is possible to embed these two schemes into a single parametric family of algorithms, and that optimal performance (in a parallel machine) is obtained by a hybrid scheme. Examples of applications to the optimization of several real steel bar structures are presented

On the need for the use of error‐controlled finite element analyses in structural shape optimization processes

This work analyzes the influence of the discretization error associated with the finite element (FE) analyses of each design configuration proposed by the structural shape optimization algorithms over the behavior of the algorithm. The paper clearly shows that if FE analyses are not accurate enough, the final solution provided by the optimization algorithm will neither be optimal nor satisfy the constraints. The need for the use of adaptive FE analysis techniques in shape optimum design will be shown. The paper proposes the combination of two strategies to reduce the computational cost related to the use of mesh adaptivity in evolutionary optimization algorithms: (a) the use of an algorithm for the mesh generation by projection of the discretization error, which reduces the computational cost associated with the adaptive FE analysis of each geometrical configuration and (b) the successive increase of the required accuracy of the FE analyses in order to obtain a considerable reduction of the computational cost in the early stages of the optimization process

An integration of a low cost adaptive remeshing strategy in the solution of structural shape optimization problems using evolutionary methods

Evolutionary methods are a powerful and robust tool for the solution of structural shape optimization problems. Nevertheless, the use of these methods requires the structural analysis of an important number of different designs, this making the computational cost of the analysis of each design a critical issue. For this reason, each design must be analyzed at a minimum computational cost but ensuring a minimum quality of the results. It is well known that the cheapest mesh for producing a solution with a fixed quality at minimum cost is an adapted one. Nevertheless, traditional adapted meshes are obtained from adaptive remeshing strategies, where each design has to be analyzed more than once, thereby also causing a high computational cost. This work presents a new strategy that allows generating an adapted mesh for each design without the necessity of performing a full adaptive remeshing procedure for each of them. It is based on the use of sensitivity analysis of all magnitudes related with adaptive remeshing (location of nodes, error estimation, etc.) with respect to the design variables. This sensitivity analysis is performed only once using a geometry of reference and it is used to project the results of the corresponding analysis to all other designs to be analyzed. The projected information allows generating an appropriate adapted mesh for each new design in one shot, greatly reducing the computational cost compared with standard strategies

Redox Potentials as Reactivity Descriptors in Electrochemistry

A redox catalyst can be present in the solution phase or immobilized on the electrode surface. When the catalyst is present in the solution phase the process can proceed via inner- (with bond formation, chemical catalysis) or outer-sphere mechanisms (without bond formation, redox catalysis). For the latter, log k is linearly proportional to the redox potential of the catalysts, E°. In contrast, for inner-sphere catalyst, the values of k are much higher than those predicted by the redox potential of the catalyst. The behaviour of these catalysts when they are confined on the electrode surface is completely different. They all seem to work as inner-sphere catalysts where a crucial step is the formation of a bond between the active site and the target molecule. Plots of (log i)E versus E° give linear or volcano correlations. What is interesting in these volcano correlations is that the falling region corresponding to strong adsorption of intermediates to the active sites is not necessarily attributed to a gradual surface occupation of active sites by intermediates (Langmuir isotherm) but rather to a gradual decrease in the amount of M(II) active sites which are transformed into M(III)OH inactive sites due to the applied potential

Control of the finite element discretization error during the convergence of structural shape optimization algorithms

This work analyzes the influence of the discretization error contained in the Finite Element (FE) analyses of each design configuration proposed by structural shape optimization algorithms over the behaviour of the algorithm. If the FE analyses are not accurate enough, the final solution will neither be optimal nor satisfy the constraints. The need for the use of adaptive FE analysis techniques in shape optimum design will be shown. The paper also proposes the use of the algorithm described in [1] in order to reduce the computational cost associated to the adaptive FE analysis of each geometrical configuration when evolutive optimization algorithms are used

RanBP2-Mediated SUMOylation Promotes Human DNA Polymerase Lambda Nuclear Localization and DNA Repair

Cellular DNA is under constant attack by a wide variety of agents, both endogenous and exogenous. To counteract DNA damage, human cells have a large collection of DNA repair factors. Among them, DNA polymerase lambda (Polλ) stands out for its versatility, as it participates in different DNA repair and damage tolerance pathways in which gap-filling DNA synthesis is required. In this work we show that human Polλ is conjugated with Small Ubiquitin-like MOdifier (SUMO) proteins both in vitro and in vivo, with Lys27 being the main target of this covalent modification. Polλ SUMOylation takes place in the nuclear pore complex and is mediated by the E3 ligase RanBP2. This post-translational modification promotes Polλ entry into the nucleus, which is required for its recruitment to DNA lesions and stimulated by DNA damage induction. Our work represents an advance in the knowledge of molecular pathways that regulate cellular localization of human Polλ, which are essential to be able to perform its functions during repair of nuclear DNA, and that might constitute an important point for the modulation of its activity in human cells

Garantías para la libertad de expresión y de opinión, en el uso de las redes sociales, frente al derecho a la honra y el buen nombre, en Colombia.

La iniciativa de este trabajo, surge con la necesidad de hacer un aporte, para la solución pacífica de los conflictos, suscitados por el uso de las redes sociales, mediante las herramientas que el Estado de Derecho nos brinda, al establecer, garantías para el ejercicio de los derechos fundamentales. Se realiza análisis de las normas de la Constitución colombiana de 1991, normas nacionales y derecho comparado, tratados, convenios internacionales y la jurisprudencia constitucional, referente a los derechos fundamentales a la libertad de expresión y de opinión, la honra y el buen nombre; se plantea un problema jurídico, sobre la colisión entre estos derechos, en el uso de las redes sociales; el origen, concepto y regulación de la redes sociales; se establece, la definición y características que enmarcan el ejercicio de los derechos fundamentales mencionados, se determinan sus diferencias y a la vez, su conexidad para ayudar a materializar otros derechos, incluso su utilidad como instrumentos para la defensa de los mismos, se logra inferir también, sobre su alcance, las garantías para su ejercicio, los requisitos para imponerles restricciones, la responsabilidad por su mal uso y afectación a terceros, así como las acciones, a través de las cuales pueden ser protegidos y por último, se compendian una serie de criterios, estándares y parámetros de ponderación, útiles, para su protección de manera efectiva y concreta.The initiative of this work, arises with the need to make a contribution, for the peaceful resolution of conflicts, caused by the use of social networks, through the tools provided by the Rule of Law, when establishing, guarantees for the exercise of the fundamental rights. Analysis of The norms of the Colombian Constitution of 1991, national norms and comparative law, treaties, international conventions and constitutional jurisprudence are analyzed, referring to the fundamental rights to freedom of expression and opinion, honor and good name; a legal problem arises, about the collision between these rights, in the use of social networks; the origin, concept and regulation of social networks; it is established, the definition and characteristics that frame the exercise of the aforementioned fundamental rights, their differences are determined and at the same time, their connection to help materialize other rights, including their usefulness as instruments for the defense of them, it is also possible to infer , on its scope, the guarantees for its exercise, the requirements to impose restrictions, the responsibility for its misuse and affectation to third parties, as well as the actions, through which they can be protected and finally, a series of criteria, standards and weighting parameters, useful, for their protection in an effective and concrete way.Introducción. -- Tema. -- Objetivo general y específicos. -- Metodología. -- 1. Derechos fundamentales. -- 1.1 Origen, concepto. -- 1.2 Derechos fundamentales en Colombia. -- 1.3 Derecho a la honra. -- 1.4 Derecho al buen nombre. -- 1.5 Derecho a la libertad de expresión y de opinión. -- 1.6 Diferencias entre algunos derechos fundamentales. -- 1.6.1 Entre el derecho a la libertad de opinión y libertad de expresión stricto sensu. -- 1.6.2 Entre el derecho a la libertad de expresión y a la información. -- 1.6.3 Entre el derecho al buen nombre y a la honra. -- 2. Las redes sociales. -- 2.1 Origen. -- 2.2 Concepto. -- 3. Libertad de expresión y de opinión, en el derecho internacional. -- a. El Pacto Internacional de Derechos Civiles y Políticos, artículo 19. -- b. Declaración Universal de Derechos Humanos, artículo 19. -- c. Convención Americana sobre Derechos Humanos, artículo 13. -- d. Declaración Americana de los Derechos y Deberes del Hombre, artículo IV. -- 4. Sobre el problema jurídico planteado. -- 5. Consideraciones de la jurisprudencia constitucional. -- 5.1 Sobre la primacía del derecho a la libertad de expresión y de opinión. -- 5.2 Garantías en la libertad de expresión y de opinión. -- 5.2.1 El anonimato como garantía. -- 5.3 Características del derecho a la libertad de expresión y de opinión. -- 5.4 Las formas de expresión que se protegen. -- 5.4.1 Los discursos especialmente protegidos por la libertad de expresión. -- 5.4.1.1. Discurso sobre asuntos políticos o de interés público. -- 5.4.1.2 Discurso sobre funcionarios públicos en ejercicio de sus funciones o candidatos a ocupar cargos públicos. -- 5.4.1.3 Discursos que expresan elementos esenciales de la identidad o dignidad personales. -- 5.4.1.4 Discursos protegidos por realizarse en ejercicio de otros derechos fundamentales. -- 5.5 Sobre los límites a la libertad de expresión y de opinión. -- 5.5.1 No son derechos absolutos. -- 5.5.2 Requisitos básicos de constitucionalidad en las limitaciones. -- 5.5.3 Los discursos expresamente prohibidos. -- 5.5.4 Estado de indefensión. -- 5.5.6 Carga de la prueba de quien pretenda su restricción. - 5.6 Responsabilidad por las publicaciones en redes sociales. -- 5.7 Habeas data y el uso de información. -- 5.8 Rectificación sobre informaciones. -- 5.9 La acción de tutela y la libertad de expresión en redes sociales. -- 5.10 La acción penal limita la libertad de expresión. -- 5.11 Acción de inconstitucionalidad. -- 6. Disposiciones en el derecho comparado. -- Resultados -- Conclusiones. -- Bibliografía

Satisfacción académica y la evitación experiencial como predictores de ansiedad generalizada en estudiantes de pregrado

Evaluar el nivel de predicción de la satisfacción académica y de la evitación experiencial sobre la ansiedad generalizada en los estudiantes de pregrado.La evitación experiencial es un concepto central de la Terapia de Aceptación y Compromiso, una de las terapias con más respaldo científico de las terapias de tercera generación. La presente investigación tuvo como objetivo evaluar el nivel de predicción de la satisfacción académica y de la evitación experiencial sobre la ansiedad generalizada en los estudiantes de pregrado. Se llevó a cabo un estudio cuantitativo, no experimental, transversal de diferencia de grupos, correlacional y predictivo. Se aplicó un conjunto de escalas (AAQ-II, HARS y ESA-8) a 196 estudiantes de pregrado. Adicional, se obtuvo como resultado que existe mayor nivel de evitación experiencial en mujeres (X¯ = 22,68) que en hombres (X¯ = 18,88) y de igual manera en el caso de la ansiedad obteniendo (X¯ = 16,38) en mujeres y (X¯ = 12,79) en hombres, en tanto a la satisfacción académica se obtuvo índices similares entre hombres y mujeres (X¯ = 16,9). También, se encontró una correlación de 0,740 entre la evitación experiencial y la ansiedad. Finalmente, se demostró mediante un modelo de mediación que la satisfacción académica predice la ansiedad de mejor manera si estas variables están mediadas por la evitación experiencial. Tras culminar con la investigación, se concluyó que los hombres y mujeres tienen niveles de ansiedad y evitación experiencial diferentes. Además, al disminuir la satisfacción académica se aumentará la ansiedad y esta aumentará aún más si existen altos niveles de evitación experiencial.Maestrí

Clinical diseases with thrombotic risk and their pharmacologycal treatment: how they change the therapeutic attitude in dental treatments

The new antiplatelets and anticoagulant drugs have been recently introduced in the daily medical practices for the control of thromboembolism associated with different diseases. The dental assistance of these patients forces us to know these drugs, understand their action mechanisms and try to decrease the risks that entail ours actions in these patients, making a thorough analysis of the risk of bleeding that is going to be related to our medical intervention, as well as the use of all the control measures of the hemorrhage from our knowledge with these patients, and to be prudent. The communication with the medical specialist that supervises these patients must be maxim, being necessary to make clinic trials for establishing protocols or guides of the handling with these patients during the odontological treatment