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Search Results: 1 - 10 of 34970 matches for " Paul Augusto Espinoza Madrid "
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Toxicología subcrónica de infusión de Chenopodium ambrosioides (epazote) por administración oral en ratones NIH Subchronic toxicology of Chenopodium ambrosioides (epazote) infusion orally administered to NIH mice
Miguel ángel Moreno Mendoza,Elvert Antonio Parada Palacios,José Guillermo Mejía Valencia,Paul Augusto Espinoza Madrid
Revista Cubana de Plantas Medicinales , 2013,
Abstract: Introducción: las plantas medicinales constituyen una valiosa alternativa terapéutica y su validación científica es una necesidad. Objetivo: identificar los posibles efectos tóxicos producidos por la infusión de Chenopodium ambrosioides L. (Chenopodiaceae) sobre el modelo biológico utilizado. Métodos: para determinar la toxicidad subcrónica de la infusión se emplearon ratones albinos suizos NIH de los 2 sexos, a los que se les administró por vía oral infusiones de la especie estudiada a concentraciones de 32, 64 y 134 mg/mL por 90 días. Al mismo tiempo se realizaron observaciones clínicas diarias con el fin de identificar algún efecto tóxico posadministración de la sustancia. Después fueron sacrificados para realizar los exámenes hematológicos (hematocrito, hemoglobina, glóbulos rojos, glóbulos blancos, neutrófilos y linfocitos) y bioquímicos (alanino aminotransferasa y creatinina), así como estudios macroscópicos e histológicos de los órganos internos (ri ón, hígado, pulmón e intestino). Resultados: se encontró que la infusión de Chenopodium ambrosioides a las dosis administradas no causó efectos determinantemente significativos en los parámetros toxicológicos, en el peso corporal, en hematología y química sanguínea, al igual que tampoco provocó alteraciones anatomopatológicas sobre los órganos y tejidos evaluados. Conclusiones: la infusión de Chenopodium ambrosioides bajo estas condiciones experimentales no presentó actividad tóxica. Introduction: medicinal plants represent a valuable therapeutic alternative and their scientific validation is a must. Objectives: to determine the possible toxic effects produced by the infusion of Chenopodium ambrosioides L. (Chenopodiaceae) on the used biological model. Methods: to determine the subchronic toxicity of the infusion, NIH Swiss albino mice of both sexes were used, to which infusions from the tested species, at concentrations of 32, 64, and 134 mg/mL , were orally administered for 90 days. At the same time, daily clinical observations were performed in order to identify any toxic post-dose administration. Afterwards, they were sacrificed for conduction of hematological tests (hematocrit, hemoglobin, red blood cells, white cells, neutrophils and lymphocytes) and biochemical (alanine aminotransferase and creatinine) and macroscopic and histological studies of the internal organs (kidney, liver, lung and intestine.). Results: the infusion of Chenopodium ambrosioides at the tested doses caused neither decisively significant effects on the toxicological parameters, body weight, hematology and blood chemistry no
Helmholtz Theorems, Gauge Transformations, General Covariance and the Empirical Meaning of Gauge Conditions  [PDF]
Andrew Chubykalo, Augusto Espinoza, Rolando Alvarado Flores
Journal of Modern Physics (JMP) , 2016, DOI: 10.4236/jmp.2016.79092
Abstract: It is well known that the use of Helmholtz decomposition theorem for static vector fields \"\", when applied to the time dependent vector fields?\"\", \"\"which represent the electromagnetic field, allows us to obtain instantaneous-like solutions all along . For this reason, some people thought (see e.g. [1] and references therein) that the Helmholtz theorem cannot be applied to time dependent vector fields and some modification is wanted in order to get the retarded solutions. However, the use of the Helmholtz theorem for static vector fields is correct even for time dependent vector fields (see, e.g. [2]), so a relation between the solutions was required, in such a way that a retarded solution can be transformed in an instantaneous one, and conversely. On this paper we want to suggest, following most of the time the mathematical formalism of Woodside in [3], that: 1) there are many Helmholtz decompositions, all equally consistent, 2) each one is naturally related to a space-time structure, 3) when we use the Helmholtz decomposition for the electromagnetic potentials it is equivalent to a gauge transformation, 4) there is a natural methodological criterion for choosing the gauge according to the structure postulated for a global space-time, 5) the Helmholtz decomposition is the manifestation at the level of the fields that a gauge is involved. So, when we relate the retarded solution to the instantaneous one what we do is to change the gauge and the space-time. And, if the Helmholtz decompositions are related to a space-time structure, and are equivalent to gauge transformations, each gauge transformation is natural for a specific space-time. In this way, a Helmholtz decomposition for Euclidean space is equivalent to the Coulomb gauge and a Helmholtz decomposition for the Minkowski space is equivalent to the Lorenz gauge. This leads us to consider that the theories defined by different gauges may be mathematically equivalent, because they can be related by means of a gauge transformation, but they are not empirically equivalent, because they have quite different observational consequences due to the different space-time structure involved.
Gauge Invariance of Gravitodynamical Potentials in the Jefimenko’s Generalized Theory of Gravitation  [PDF]
Augusto Espinoza, Andrew Chubykalo, David Perez Carlos
Journal of Modern Physics (JMP) , 2016, DOI: 10.4236/jmp.2016.713146
Abstract: In the Jefimenko’s generalized theory of gravitation, it is proposed the existence of certain potentials to help us to calculate the gravitational and cogravitational fields, such potentials are also presumed non-invariant under certain gauge transformations. In return, we propose that there is a way to perform the calculation of certain potentials that can be derived without using some kind of gauge transformation, and to achieve this we apply the Helmholtz’s theorem. This procedure leads to the conclusion that both gravitational and cogravitational fields propagate simultaneously in a delayed and in an instant manner. On the other hand, it is also concluded that these potentials thus obtained can be real physical quantities, unlike potentials obtained by Jefimenko, which are only used as a mathematical tool for calculating gravitational and cogravitational fields.
On the Question of the Invariance of the Light Speed  [PDF]
Sergey N. Artekha, Andrew Chubykalo, Augusto Espinoza
Journal of Modern Physics (JMP) , 2017, DOI: 10.4236/jmp.2017.88080
Abstract: This article is devoted to the key concept of modern electrodynamics—the invariance of the speed of light. The general principle of relativity is considered in detail. Some critical remarks to the relativistic invariance and to the Lorentz transformations are presented. The general invariance of Maxwell equations is discussed. Different theoretical expectations for possible results of Michelson-Morley experiment and some physical consequences are considered. Some critical remarks to the notion of the light speed and its constancy are given. The relativistic law for velocity addition, including strangeness of a noncollinear addition and a superluminal motion, is discussed. Critical analysis of two works which proof the need for existence of an invariant velocity is consequentially made.
Una paradoja de la situación intelectual contemporánea: de las políticas de estado, una reflexión desde Kelsen y Kant
Augusto Bolívar Espinoza
Polis : Revista de la Universidad Bolivariana , 2004,
Abstract:
El ciudadano y la noción de lo público
Augusto Bolívar Espinoza
Polis : Revista de la Universidad Bolivariana , 2004,
Abstract:
Las políticas mexicanas transnacionales. Un desafío para la integración regional
Augusto Bolívar Espinoza
El Cotidiano , 2010,
Abstract: El Proyecto Puebla Panamá (PPP), impulsado por México en 2001, se ha convertido en 2008 en el Proyecto de Integración y Desarrollo de Mesoamérica (PM). Este cambio marca una dirección hacia una política de unión regional mesoamericana que se enfrentará a las políticas nacionales de integración tradicionales impulsadas por México desde los a os ochenta. El escrito pretende clarificar el lugar que hasta ahora ha tenido el PPP para México y destacar el desafío que supondrá para el país la inserción en un proceso de Unión Mesoamericana, mostrar las instancias más generales del PPP donde se inserta la política transnacional mexicana en Mesoamérica, y sensibilizar las nuevas instancias y objetivos del Proyecto Mesoamericano.
On Some Unusual Properties of Wave Solutions of Free Maxwell Equations
Augusto Espinoza,Andrey Chubykalo
Ciencia Ergo Sum , 2006,
Abstract: Se descubren algunas propiedades inusuales de las soluciones de las llamadas ecuaciones libres de Maxwell. Mostramos la existencia de soluciones que representan las ondas electromagnéticas en el vacío para los cuales el vector de Poynting no coincide con el vector de Umov. Se presentan soluciones que corresponden a ondas magnéticas estacionarias de una configuración inusual en el vacío, que describen en el vacio formaciones estables anulares y esféricas de campo. Se demuestra que en el vacío, de acuerdo a las soluciones obtenidas el campo eléctrico E puede ser un vector polar así como un vector axial; y el campo magnético B, en su turno, puede ser un vector axial así como también un vector polar. Se muestra que tales soluciones existen cuando los vectores E y B, no son vectores polares ni axiales. Además, estas soluciones corresponden a ondas electromagnéticas que no transfieren energía ni momentos en cualquier punto del vacío.
Conceptual Content of the Generalized Theory of Gravitation of Jefimenko  [PDF]
Andrew Chubykalo, Augusto Espinoza, David Pérez Carlos
Journal of Modern Physics (JMP) , 2018, DOI: 10.4236/jmp.2018.98094
Abstract: In this work, we make a brief exposition of the Jefimenko’s generalized theory of gravitation, describe its conceptual content, explain the mathematical apparatus used for the formulations of the theory and present the fundamental equations of the theory. We elucidate the main difference between Newton’s original theory of gravitation and the generalized theory of gravitation.
Sen y algunos escritos en la constitución del campo del Desarrollo Humano (Bibliografía anotada de Amartya Sen)
Bolívar Espinoza,Gardy Augusto;
Polis (Santiago) , 2009,
Abstract: a brief and synthetic route of the published theoretical production of amartya sen and some classic texts that accompany the foundation by the field of the human development are hereby presented. the intention is to show the process of her thought and the diversity of subjects she raises. the assumption is that sen synthetically expresses the complexity of the field.
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