Convergence Time Towards Periodic Orbits in Discrete Dynamical Systems

We investigate the convergence towards periodic orbits in discrete dynamical systems. We examine the probability that a randomly chosen point converges to a particular neighborhood of a periodic orbit in a fixed number of iterations, and we use linearized equations to examine the evolution near that neighborhood. The underlying idea is that points of stable periodic orbit are associated with intervals. We state and prove a theorem that details what regions of phase space are mapped into these intervals (once they are known) and how many iterations are required to get there. We also construct algorithms that allow our theoretical results to be implemented successfully in practice.Comment: 17 pages; 7 figure

Understanding intellectual disability through RASopathies

Intellectual disability, commonly known as mental retardation in the International Classification of Disease from World Health Organization, is the term that describes an intellectual and adaptive cognitive disability that begins in early life during the developmental period. Currently the term intellectual disability is the preferred one. Although our understanding of the physiological basis of learning and learning disability is poor, a general idea is that such condition is quite permanent. However, investigations in animal models suggest that learning disability can be functional in nature and as such reversible through pharmacology or appropriate learning paradigms. A fraction of the cases of intellectual disability is caused by point mutations or deletions in genes that encode for proteins of the RAS/MAP kinase signaling pathway known as RASopathies. Here we examined the current understanding of the molecular mechanisms involved in this group of genetic disorders focusing in studies which provide evidence that intellectual disability is potentially treatable and curable. The evidence presented supports the idea that with the appropriate understanding of the molecular mechanisms involved, intellectual disability could be treated pharmacologically and perhaps through specific mechanistic-based teaching strategies.Fil: San Martín, Alvaro. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Fisiología y Biofísica Bernardo Houssay. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Fisiología y Biofísica Bernardo Houssay; ArgentinaFil: Pagani, Mario Rafael. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Fisiología y Biofísica Bernardo Houssay. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Fisiología y Biofísica Bernardo Houssay; Argentin

Hybrid SGP4 orbit propagator

Two-Line Elements (TLEs) continue to be the sole public source of orbiter observations. The accuracy of TLE propagations through the Simplified General Perturbations-4 (SGP4) software decreases dramatically as the propagation horizon increases, and thus the period of validity of TLEs is very limited. As a result, TLEs are gradually becoming insufficient for the growing demands of Space Situational Awareness (SSA). We propose a technique, based on the hybrid propagation methodology, aimed at extending TLE validity with minimal changes to the current TLE-SGP4 system in a non-intrusive way. It requires that the institution in possession of the osculating elements distributes hybrid TLEs, HTLEs, which encapsulate the standard TLE and the model of its propagation error. The validity extension can be accomplished when the end user processes HTLEs through the hybrid SGP4 propagator, HSGP4, which comprises the standard SGP4 and an error corrector.Comment: 18 pages, 4 figure

Composition law of cardinal order permutations

In this paper the theorems that determine composition laws for both cardinal ordering permutations and their inverses are proven. So, the relative positions of points in a hs-periodic orbit become completely known as well as in which order those points are visited. No matter how a hs-periodic orbit emerges, be it through a period doubling cascade (s=2^n) of the h-periodic orbit, or as a primary window (like the saddle-node bifurcation cascade with h=2^n), or as a secondary window (the birth of a $s-$periodic window inside the h-periodic one). Certainly, period doubling cascade orbits are particular cases with h=2 and s=2^n. Both composition laws are also shown in algorithmic way for their easy use

Immigrants\u27 Rights in the Public Sphere: Hannah Arendt\u27s Concepts Reconsidered

Based on Arendt\u27s concepts of public and private spheres, immigration issues can be approached from an emphasis on how the most fundamental of all human rights, which is being denied to immigrants, is the most basic constituent of the human condition: the ability to interact in the public realm through action and speech. The granting of this right would enable immigrants to become unique human beings, with the capacity for transformation. As they are presently deprived of these and other rights, they are confined to the most primitive sphere, that is, the one of pure survival. Therefore, a differentiation must be made between dissimilarities in the nature of reception and treatment of diverse immigrants\u27 groups

El criterio Popperiano de la cientificidad aplicado a Freud y Einstein

Para Popper, la actitud verdaderamente científica se encuentra representada en forma paradigmática por científicos del estilo de Einstein, en los que predomina el interés por encontrar "experimentos cruciales" para poner a prueba la sustentabilidad de una teoría por sobre el interés por verificarla o confirmarla. Polarmente contrapuesta a esta actitud crítica aparece la actitud dogmática -representada paradigmáticamente, entre otros, por Freud-, que se caracteriza por la búsqueda de posibles verificaciones de la teoría. Mientras que Einstein constituye un modelo de actitud verdaderamente científica, Freud aparece como representante de un estilo de pensamiento dogmático, precientifico y, eventualmente, hasta pseudocientifico (Schilpp 1974: 29-31)

PRESENTACIÓN EL SUJETO EN LA EDUCACIÓN Y LA EDUCACIÓN EN EL SUJETO

Este estudio parte de una necesidad real de la actualidad educativa, que está suprimiendo las consideraciones antropológicas, y está enrumbándose por un lado en estructuraciones muy psicológicas, que no obstante su rigor científico, sin embargo, parcializan el sujeto considerándolo: o un ente determinado por el ambiente; o portador de una carga hereditaria que lo estigmatizará; o una estructura que relativiza el ambiente o la herencia, insertándole en una ingenuidad pedagógica, de la cual se deduce un voluntarismo triunfalista. Por otro lado, construyendo un sujeto, con un telón de fondo histórico social, que proyectará: o la intención del mercado, por tanto un sujeto en relaciones de intercambio; o de la instrumentalización por medio de adiestramiento en la tecnología; o de exageración en la identidad, que sacrifica el horizonte social y se contextualiza demasiado en la herencia cultural. Tanto en la una como en la otra perspectiva, el perjudicado es el sujeto, que termina ignorándose a sí mismo e ignorado por los otros

La vida radical como conciencia trascendental

Este texto corresponde a una conferencia dictada en el III Congreso Internacional de Fenomenología y Hermenéutica, organizado por el Departamento de Humanidades de la Universidad Andrés Bello los días 12,13 y 14 de octubre de 2011.Indexación: Revista UNABComo no pasará desapercibido a los conocedores de Ortega y Husserl, en el título he juntado a ambos. Seguro que sonará extraño a más de uno. Yo mismo he tardado en llegar a esa formulación precisa porque para ello he tenido que superar un largo camino de dificultades, provenientes tanto de Husserl como de Ortega. Superar esas dificultades me llevaron su tiempo, pero creo que al final tengo razones suficientes para poder formular ese título. Con él estoy indicando que lo que Husserl llamaba conciencia o subjetividad trascendental no es sino lo que Ortega llamaba “realidad” radical. Prefiero poner la palabra “realidad” entre comillas porque posiblemente es una palabra inadecuada a las características de ser propias del ser humano. Pero a la vez quiero decir que lo que Ortega tenía in mente cuando hablaba de “realidad” radical no era distinto de lo que Husserl tenía in mente cuando hablaba de conciencia, subjetividad o vida trascendental. Y ruego que anoten el progreso y equivalencia de los tres términos porque es imprescindible en mi argumentación.http://revistahumanidades.unab.cl/wp-content/uploads/2014/02/D1.-SAN-MARTIN.pd