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The Hamilton-Jacobi formalism is used to analyze the Weyl theory in the weak-field limit. The complete set of involutive Hamiltonians is obtained, which are classified into involutive and non-involutive. The counting of degrees of freedom is performed. Additionally, the generalized brackets and gauge symmetries are reported.

The Hamilton-Jacobi $[HJ]$ study for the Chern-Simons $[CS]$ modification of general relativity $[GR]$ is performed. The complete structure of the Hamiltonians and the generalized brackets are reported, from these results the $HJ$ fundamental differential is constructed and the symmetries of the theory are found. By using the Hamiltonians we remove an apparent Ostrogradsky's instability and the new structure of the hamiltonian is reported. In addition, the counting of physical degrees of freedom is developed and some remarks are discussed.

A detailed canonical analysis for three-dimensional massive gravity is performed. The construction of the fundamental Dirac brackets, the complete structure of the constraints and the counting of the physical degrees of freedom are reported. In addition, it is shown that the extended Hamiltonian is healed from Orstrogradki's instabilities.

The Hamilton-Jacobi [$HJ$] analysis for higher-order Chern-Simons gravity is performed. The complete set of $HJ$ Hamiltonians are identified and a fundamental $HJ$ differential is constructed, from which the characteristic equations are obtained. In addition, the symmetries of the theory are identified and the obtained results are compared with other approaches reported in the literature.

By using the Hamilton-Jacobi [$HJ$] framework the higher-order Maxwell-Chern-Simons theory is analyzed. The complete set of $HJ$ Hamiltonians and a generalized $HJ$ differential are reported, from which all symmetries of the theory are identified. In addition, we complete our study by performing the higher order Gitman-Lyakhovich-Tyutin [$GLT$] framework and compare the results of both formalisms.

By using the Hamilton-Jacobi [HJ] framework the three dimensional Palatini theory plus a Chern-Simons term [PCS] is analyzed. We report the complete set of $HJ$ Hamiltonians and a generalized $HJ$ differential from which all symmetries of the theory are identified. Moreover, we show that in spite of PCS Lagrangian produces Einstein's equations, the generalized $HJ$ brackets depend on a Barbero-Immirzi like parameter. In addition we complete our study by performing a canonical covariant analysis, and we construct a closed and gauge invariant two form that encodes the symplectic geometry of the covariant phase space.

Don Alberto Cañas, ensayista, político, escritor, es una de las figuras intelectuales más sobresalientes de la política y la cultura costarricense. Ofrece su visión sobre la dramaturgia en la segunda mitad del siglo XX.

A detailed Faddeev-Jackiw quantization of an Abelian topological gravity is performed; we show that this formalism is equivalent and more economical than Dirac's method. In particular, we identify the complete set of constraints of the theory, from which the number of physical degrees of freedom is explicitly computed. We prove that the generalized Faddeev-Jackiw brackets and the Dirac ones coincide to each other. Moreover, we perform the Faddeev-Jackiw analysis of the theory at the chiral point, and the full set of constraints and the generalized Faddeev-Jackiw brackets are constructed. Finally we compare our results with those found in the literature and we discuss some remarks and prospects.

A detailed Dirac's and Faddeev-Jackiw quantization of Bonzom-Livine model describing gravity in three dimensions is performed. The full structure of the constraints, the gauge transformations and the generalized Faddeev-Jackiw brackets are found. In addition, we show that the Faddeev-Jackiw and Dirac's brackets coincide to each other. Finally we discuss some remarks and prospects.

The objective of this study was to determine the effect of nitrogen on the production and abscission of reproductive organs and dry bean yield. This research was carried out in Iguala, Guerrero, Mexico where the climate is hot and subhumid. The Michoacan 12A3 bean variety, was sown on November 17, 1989, and December 17, 1990, with irrigation (autumn), and June 1, 1990 and June 29, 1991, without irrigation (summer). Population density was 13.3 plants/m-2. Treatments of zero and 80 kg N ha-1 were applied in each experiment. Results indicated that in both sowing seasons N increased leaf area, production and abscission of reproductive organs, number of pods reaching physiological maturity, and seed yield. As compared to the control, the higher abscission of reproductive organs in plants with N limited a higher seed yield under this treatment. Bean production in autumn was higher than in the summer. El objetivo de este estudio fue determinar el efecto del nitrógeno sobre la producción y abscisión de órganos reproductivos y el rendimiento del frijol. La investigación se realizó en Iguala Gro., México de clima cálido subhúmedo. La variedad Michoacán -12A3 fue sembrada con riego en noviembre 17 de 1989 y diciembre 17 de 1990 y en secano en junio 1 de 1990 (Otoño) y junio 29 de 1991 (Verano), a la densidad de 13,3 plantas m-2. En cada experimento se aplicaron tratamientos de 0 y 80 kg N ha-1. Los resultados indicaron que en ambas épocas de siembras, el nitrógeno incrementó el área foliar, la producción y abscisión de órganos reproductivos, el número de vainas a la madurez fisiológica y el rendimiento. La mayor abscisión de órganos en las plantas con nitrógeno en relación al testigo, fue limitante para lograr un mayor incremento en el rendimiento del frijol bajo este tratamiento. La producción del frijol en las siembras de otoño fue superior a las de verano.

In this paper the Dirac and Faddeev-Jackiw formulation for Einstein's theory in the $G \rightarrow 0$ limit is performed; the fundamental Dirac's and Faddeev-Jackiw brackets for the theory are obtained. First, the Dirac brackets are constructed by eliminating the second class constraints remaining the first class ones, then we fix the gauge and we convert the first class constraints into second class constraints and the new fundamental Dirac's brackets are computed. Alternatively, we reproduce all relevant Dirac's results by means of the symplectic method. We identify the Faddeev-Jackiw constraints and we prove that the Dirac and the Faddeev-Jackiw brackets coincide to each other. .

A detailed Hamiltonian analysis for a five-dimensional St{\"{u}}eckelberg theory with a compact dimension is performed. First, we develop a pure Dirac's analysis of the theory, we show that after performing the compactification, the theory is reduced to four-dimensional St{\"{u}}eckelberg theory plus a tower of Kaluza-Klein modes. We develop a complete analysis of the constraints, we fix the gauge and we show that there are present pseudo-Goldstone bosons. Then we quantize the theory by constructing the Dirac brackets. As complementary work, we perform the Faddeev-Jackiw quantization for the theory under study, and we calculate the generalized Faddeev-Jackiw brackets, we show that both the Faddeev-Jackiw and Dirac's brackets are the same. Finally we discuss some remarks and prospects.

A detailed Hamiltonian analysis for a five-dimensional St{��}eckelberg theory with a compact dimension is performed. First, we develop a pure Dirac's analysis of the theory, we show that after performing the compactification, the theory is reduced to four-dimensional St{��}eckelberg theory plus a tower of Kaluza-Klein modes. We develop a complete analysis of the constraints, we fix the gauge and we show that there are present pseudo-Goldstone bosons. Then we quantize the theory by constructing the Dirac brackets. As complementary work, we perform the Faddeev-Jackiw quantization for the theory under study, and we calculate the generalized Faddeev-Jackiw brackets, we show that both the Faddeev-Jackiw and Dirac's brackets are the same. Finally we discuss some remarks and prospects.

A detailed Dirac's canonical analysis for a topological four dimensional $BF$-like theory with a compact dimension is developed. By performing the compactification process we find out the relevant symmetries of the theory, namely, the full structure of the constraints and the extended action. We show that the extended Hamiltonian is a linear combination of first class constraints, which means that the general covariance of the theory is not affected by the compactification process. Furthermore, in order to carry out the correct counting of physical degrees of freedom, we show that must be taken into account reducibility conditions among the first class constraints associated to the excited KK modes. Moreover, we perform the Hamiltonian analysis of Maxwell theory written as a $BF$-like theory with a compact dimension, we analyze the constraints of the theory and we calculate the fundamental Dirac's brackets, finally the results obtained are compared with those found in the literature.

We develop a complete Dirac's canonical analysis for an alternative action that yields Maxwell's four-dimensional equations of motion. We study in detail the full symmetries of the action by following all steps of Dirac's method in order to obtain a detailed description of symmetries. Our results indicate that such an action does not have the same symmetries than Maxwell theory, namely, the model is not a gauge theory and the number of physical degrees of freedom are different.

The Hamiltonian analysis for the Euler and Second-Chern classes is performed. We show that, in spite of the fact that the Second-Chern and Euler invariants give rise to the same equations of motion, their corresponding symplectic structures on the phase space are different, therefore, one can expect different quantum formulations. In addition, the symmetries of actions written as a BF-like theory that lead to Yang-Mills equations of motion are studied. A close relationship with the results obtained in previous works for the Second-Chern and Euler classes is found.

The Hamiltonian analysis for the Einstein's action in $ G\to 0 $ limit is performed. Considering the original configuration space without involve the usual $ADM$ variables we show that the version $ Gto 0 $ for Einstein's action is devoid of physical degrees of freedom. In addition, we will identify the relevant symmetries of the theory such as the extended action, the extended Hamiltonian, the gauge transformations and the algebra of the constraints. As complement part of this work, we develop the covariant canonical formalism where will be constructed a closed and gauge invariant symplectic form. In particular, using the geometric form we will obtain by means of other way the same symmetries that we found using the Hamiltonian analysis.

Using basic ideas of simplectic geometry, we find the covariant canonically conjugate variables, the commutation relations and the Poincar\'e charges for chiral superconducting membranes (with null currents), as well as we find the stress tensor for the theory under study., Comment: 13 pages

We consider the Regge-Teitelboim model for a relativistic extended object embedded in a fixed background Minkowski spacetime, in which the dynamics is determined by an action proportional to the integral of the scalar curvature of the worldvolume spanned by the object in its evolution. In appearance, this action resembles the Einstein-Hilbert action for vacuum General Relativity: the equations of motion for both are second order; the difference is that here the dynamical variables are not the metric, but the embedding functions of the worldvolume. We provide a novel Hamiltonian formulation for this model. The Lagrangian, like that of General Relativity, is linear in the acceleration of the extended object. As such, the model is not a genuine higher derivative theory, a fact reflected in the order of the equations of motion. Nevertheless, as we will show, it is possible as well as useful to treat it as a `fake' higher derivative system, enlarging the phase space appropriately. The corresponding Hamiltonian on this phase space is constructed: it is a polynomial. The complete set of constraints on the phase space is identified. The fact that the equations of motion are of second order in derivatives of the field variables manifests itself in the Hamiltonian formulation through the appearance of additional constraints, both primary and secondary. These new constraints are second class. In this formulation, the Lagrange multipliers implementing the primary constraints get identified as accelerations. This is a generic feature of any Lagrangian linear in the acceleration possessing reparametrization invariance., 9 pages

Using basic ideas of simplectic geometry, we find the covariant canonically conjugate variables, the commutation relations and the Poincar�� charges for chiral superconducting membranes (with null currents), as well as we find the stress tensor for the theory under study., 13 pages

Using a strongly covariant formalism given by Carter for the deformations dynamics of p-branes in a curved background and a covariant and gauge invariant geometric structure constructed on the corresponding Witten's phase space, we identify the canonical variables for Dirac-Nambu-Goto [DNG] and Gauss-Bonnet [GB] system in string theory. Future extensions of the present results are outlined., 12 pages

Using a covariant and gauge invariant geometric structure constructed on the Witten covariant phase space for Dirac-Nambu-Goto bosonic p-branes propagating in a curved background, we find the canonically conjugate variables, and the relevant commutation relations are considered, as well as, we find the canonical variables for the Gauss-Bonnet topological term in string theory., 8 pages

A pure Dirac's method of Yang-Mills expressed as a constrained BF-like theory is performed. In this paper we study an action principle composed by the coupling of two topological BF-like theories, which at the Lagrangian level reproduces Yang-Mills equations. By a pure Dirac's method we mean that we consider all the variables that occur in the Lagrangian density as dynamical variables and not only those ones that involve temporal derivatives. The analysis in the complete phase space enable us to calculate the extended Hamiltonian, the extended action, the constraint algebra, the gauge transformations and then we carry out the counting of degrees of freedom. We show that the constrained BF-like theory correspond at classical level to Yang-Mills theory. From the results obtained, we discuss briefly the quantization of the theory. In addition we compare our results with alternatives models that have been reported in the literature

La presente tesis presenta los resultados obtenidos de una investigación realizada dentro un grupo de sexto grado de primaria implementando un plan estratégico que desarrollara y/o elevara habilidades que requieren para su proceso enseñanza-aprendizaje, tomando como premisa estar consciente o no de pertenecer a dicho grupo de estudio y las implicaciones que esto ocasionaba dentro del grupo, considerándolo como motivador para el desarrollo del trabajo. Se establecieron dentro del plan estrategias de trabajo específicas como elaboración de mapas mentales y cuadros comparativos, enfocadas a la habilidad de conceptualización de hechos, ya que éstas apoyan en la mejora de las capacidades adquiridas y en proceso de los alumnos, presentando los resultados necesarios para evaluar y reestructurar el plan y ser aplicado en otros grados y con otras materias. Este tema proporciona elementos importantes para el docente y el trabajo que realiza dentro del aula, permitiéndole conocer la importancia de las estrategias de trabajo y el impacto que tienen éstas dentro del salón de clases. Se enfocan dentro del plan estratégico los objetivos que el investigador pretendió demostrar tanto como los métodos y estrategias de aplicación del mismo, así como también la importancia de conocer los métodos de evaluación que lleva a cabo el colegio y la importancia de medir y evaluar las habilidades para desarrollarlas en los alumnos y que logre los objetivos de aprendizaje planteados.

El presente estudio surge de la intención por contribuir a la mejora del proceso de enseñanza – aprendizaje que de acuerdo a investigaciones, entre otros factores, se puede encontrar obstaculizado por la falta de motivación de los estudiantes hacia las clases, lo que les ocasiona aburrimiento, el cual a su vez genera estrés negativo en los docentes. El objetivo principal de este trabajo fue medir el impacto que tiene una estrategia de inteligencia emocional en la autorregulación del aburrimiento experimentado por los estudiantes de primero de secundaria en la clase de matemáticas de una institución educativa privada. Para ello se siguió un enfoque metodológico mixto con un diseño secuencial explicativo donde los datos de carácter cualitativo complementan y explican los de tipo cuantitativo. Los instrumentos utilizados fueron escala tipo Likert, entrevista, observación sistemática, observación naturalista y la propia estrategia basada en la inteligencia emocional. La muestra estuvo conformada por 67 estudiantes de primero de secundaria distribuidos en dos grupo (control y experimental). Los resultados mostraron que el aburrimiento fue autorregulado significativamente, los comportamientos que denotaban falta de atención disminuyeron durante la implementación de la estrategia y la escala tipo Likert reflejó un cambio de la percepción de los alumnos hacia la clase de matemáticas. Los pensamientos subyacentes en la experimentación del aburrimiento en la clase de matemáticas estuvieron vinculados a la percepción de monotonía, falta de un rol activo por parte del estudiante y carencia del componente lúdico. El aburrimiento, afrontado activamente, llevó a los alumnos a descubrir sus propios intereses, no obstante se necesita de la participación de los docentes y directivos de las instituciones educativas para lograr un ambiente constructivista del aprendizaje.

El estudio se enmarca en el tipo de investigación cuantitativa y fue realizado en una institución pública rural del departamento Norte de Santander de Colombia. El objetivo del proyecto fue determinar la validez de instrumentos de síntesis de información y de reconocimiento de información para la detección de aprendizaje significativo de Ciencias según la Teoría de Ciencias en estudiantes de grado Noveno de Secundaria, la metodología consistió en diseñar y aplicar dos clases de instrumentos: pruebas de reactivos de opción múltiple y pruebas con mapas conceptuales, se realizaron tres intervenciones para cada tipo de prueba en tres temáticas de ciencias naturales (Teorías sobre el origen de la vida, evolución y genética molecular). Se realizó análisis estadístico determinando medias, desviación estándar, índice biserial puntual, índice de discriminación e índice de dificultad para las pruebas con reactivos de opción múltiple; y para las pruebas con mapas conceptuales se determinó la media y desviación estándar de las calificaciones obtenidas en la misma escala utilizada para las anteriores pruebas, se realizó un análisis de puntuación para los cinco parámetros evaluados (Número de conceptos escogidos, número de conceptos válidos, valoración de jerarquía, número de palabras conectoras incluidas y número de palabras conectoras válidas). Para comparar los dos tipos de pruebas se realizó la prueba de comparación estadística de medias con una distribución de t-Student. El análisis de medias dio como resultado un valor de 0,43, lo que permitió establecer que la hipótesis nula se rechaza, esta decía: “No existe una diferencia significativa de la validez entre instrumentos de síntesis de la información e instrumentos de reconocimiento de la información para la de detección del aprendizaje significativo de Ciencias según la teoría de Ausubel en los estudiantes de grado Noveno”; y se acepta hipótesis alternativa que plantea: “Existe diferencia significativa de la validez entre instrumentos de síntesis de la información e instrumentos de reconocimiento de la información para la de detección del aprendizaje significativo de Ciencias según la teoría de Ausubel en los estudiantes de grado Noveno”.