Factores que afectan a la compresión de comprimidos

La necesidad de añadir excipientes a la formulación viene determinada por las propiedades físico — químicas y de estabilidad del principio activo. La caracterización de comprimidos se lleva a cabo mediante muestreo al azar después del proceso de fabricación, e incluye la determinación y comprobación de características físicas, químicas y biofarmacéuticas. Estos controles son fundamentales para garantizar la eficacia y seguridad del medicamento y que presente unas buenas propiedades de disgregación y disolución, entre otras. Las especificaciones y directrices para medir los parámetros se encuentran recogidos en la Real Farmacopea Española. Entre estos parámetros se encuentran: la observación de las características externas, ensayo de uniformidad de masa, altura, diámetro, ensayo de disgregación, resistencia a la fractura o dureza, friabilidad y ensayo de contenido. Los excipientes juegan un papel muy importante en la formulación de comprimidos, ya que no sólo ayudan a mejorar el proceso de fabricación del medicamento, sino que también facilitan la desintegración, funcionan como vehículo de transporte del principio activo, protegen de diferentes factores tales como la luz, temperatura y oxidación, mejoran el sabor y proporcionan una identificación. En el presente estudio se ha llevado a cabo la caracterización de 9 lotes de comprimidos con un principio activo determinado y diferentes tipos de excipientes, donde en concreto varían el tipo de disgregante y de aglutinante utilizados. A estos lotes de comprimidos se les realizó una serie de ensayos: uniformidad de masa, medida del diámetro y de la altura, dureza, friabilidad y tiempo de disgregación. Una vez obtenidos los resultados fueron comparados entre sí para ver como afectaban los excipientes empleados a la compresión de los comprimidos y poder determinar cual es el lote más idóneo y por tanto los mejores excipientes para ese principio activo.Universidad de Sevilla. Grado en Farmaci

The Durban Conference Against Racism and Everyone\u27s Responsibilities

WHEN DELEGATES AND observers to the third United Nations conference against racism left the premises in Durban, South Africa, exhausted and still stunned by the difficulties they had faced, they did not have a hint of what was soon to happen. They knew that only by means of accommodation and last minute procedural maneuvers had they managed to reach a consensus on the final documents. This should have been enough to tone down any possible enthusiasm. Nevertheless, for most of them, results had undoubtedly had positive aspects. There were reasons to believe the Conference had been worthwhile

Proportionality Analysis as an ‘Analytical Matrix’ Adopted by the Supreme Court of Mexico

This paper explores proportionality analysis as a constitutional standard that allows courts to engage in a public conversation, especially with the legislature. This conversation would consider the concept, structure and normative force of fundamental rights, the way in which two or more rights compete and collide, and as to how a particular disagreement about rights can be addressed. What is particularly appealing is the way in which this approach to proportionality analysis does not prescribe any legitimate means ‘per se’. It is relational because it must apply the means to achieve a particular aim in a real situation and decide if the sacrifice applied to a particular right is proportionate. This may eventually offer better public engagement with judicial arguments and endorse judicial independence by rendering the decision more structured, open and transparent. A further aim of this paper is to fulfill the knowledge gap about the migration of proportionality analysis as a rights adjudication mechanism to Latin America and, at the same time, make a claim for a context-sensitive approach. The hope is that judiciaries will learn from recent pitfalls that occurred under authoritarian regimes in Latin America where decisions were based upon excessive formality and disregard of relevant factors involved in rights claims. The recent adoption of proportionality analysis by the Mexican Supreme Court in 2007 has created the option of a new appraisal of its migration to Latin America

Trace anomaly of the conformal gauge field

The proposed by Bastianelli and van Nieuwenhuizen new method of calculations of trace anomalies is applied in the conformal gauge field case. The result is then reproduced by the heat equation method. An error in previous calculation is corrected. It is pointed out that the introducing gauge symmetries into a given system by a field-enlarging transformation can result in unexpected quantum effects even for trivial configurations.Comment: 9 pages, LaTeX file, BI-TP 93/3

Implementation of a two-dimensional discrete element method to describe granular materials composed of elliptical cohesionless particles

This work is aimed at developing a discrete element simulation that models the contact between elliptical grains or particles in granular materials. The goal is to implement an algorithm to carry out collision detection between ellipses as well as ellipsoidal objects. The practical issue here is that the real shape of macroscopic grains can be approximated better using elliptical curves than using spherical curves. In addition, the simulation model will also be valid for spheres, since these objects are special cases of ellipsoids. An accurate contact detection algorithm was investigated by means of two different formulations. The first formulation determines the minimum distance of one ellipse with respect to another ellipse and vice versa and finds the two closest points. Then it analyzes the position of these two points. However, this formulation is not robust enough to determine all the contact detections tested. The first formulation fails in cases when the distance between centers is unrealistically close and the major and minor axes are large. The second formulation determines the overlap distance. This method was successful in each of the realistic cases tested. The second formulation, as well as the first formulation, fails in unphysical cases, i.e., the distance between the centers of the ellipses is much smaller than the size of the major and minor axes of the ellipses. The implementation of a contact force formulation with minimum overlap distance will remove any possibility that these cases occur

Le Modèle de la coopérative peut-il permettre l'intégration des populations actuellement mattginalisée en Europe ?

International audienceThe model of the cooperatives is a model that have already studied. Nevertheless the situations of the marginalized populations remain difficult in our country. This article aims to find some possible solutions that can be developped using this a network of cooperatives to help varius population to cooperate.Le modèle de la coopérative est un modèle déjà bien étudié dans nos économies. Les situations des personnes marginalisées demeurent délicates dans nos pays. Cet article se propose aux regards de situations décrites d’explorer des axes de solutions