441 research outputs found

    Spinocerebellar Ataxia Type 2

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    1. Introduction: The autosomal dominant cerebellar ataxias (ADCA) are a clinically, pathologically and genetically heterogeneous group of neurodegenerative disorders caused by degeneration of cerebellum and its afferent and efferent connections. The degenerative process may additionally involves the ponto- medullar systems, pyramidal tracts, basal ganglia, cerebral cortex, peripheral nerves (ADCA I) and the retina (ADCA II), or can be limited to the cerebellum (ADCA III) (Harding et al., 1993). The most common of these dominantly inherited autosomal ataxias, ADCA I, includes many Spinocerebellar Ataxias (SCA) subtypes, some of which are caused by pathological CAG trinucleotide repeat expansion in the coding region on the mutated gene. Such is the case for SCA1, SCA2, SCA3/MJD, SCA6, SCA7, SCA17 and Dentatorubral-pallidoluysian atrophy (DRPLA) (Matilla et al., 2006). Among the almost 30 SCAs, the variant SCA2 is the second most prevalent subtype worldwide, only surpassed by SCA3 (Schöls et al., 2004; Matilla et al., 2006; Auburger, 2011)..

    Salud Pública

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    La unidad de aprendizaje de Salud Pública, tiene la finalidad que los dicentes adquieran los conocimientos y habilidades necesarios para la atención de la problemática de la salud pública encaminada a promoción de la salud, prevención y control de los riesgos sanitarios en la población humana, considerando la magnitud, trascendencia y vulnerabilidad de las enfermedades que comparten el hombre y los animales. La capacitación en el manejo de métodos y técnicas de estudio aplicadas a determinar los estimadores en salud, permite analizar y resolver problemas epidemiológicos, quedando en la posición de poder elaborar y aplicar los programas operativos en Salud pública. La Salud Pública Veterinaria es la aplicación de aquellos campos en los que la Medicina Veterinaria comparte un interés común con la Salud Pública. Incluye actividades, en el que las técnicas veterinarias se aplican para la solución de los problemas de salud y enfermedades que afectan a las poblaciones. En la actualidad se ha propuesto la convergencia de estas dos vertientes por el de una salud. La Medicina Veterinaria incrementa la productividad de los animales domésticos, actúa en la prevención de la desnutrición en el hombre al ofrecer productos de origen animal inocuos para la alimentación. La identificación, prevención y el control de las zoonosis, además de las situaciones de emergencia sanitaria y desastres naturales que impactan la Salud Pública. Los conocimientos anteriores en la formación del Médico Veterinario Zootecnista, para su práctica profesional, juega un papel de suma importancia en el enfoque de la Salud Pública. La relevancia de este curso se adquiere una vez que los dicentes adquieren los conocimientos y las estrategias de atención sanitaria para integrarse a los programas sectoriales de interés en la Salud de la comunidad, además de proponer su intervención en la Salud con un espíritu innovador a lo puesto en práctica

    Analysis of air flow past and through the 2415-3S airfoil for an unmanned aerial vehicle with internal propulsion system

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    This paper deals with the prediction of velocity fields on the 2415-3S airfoil which will be used for an unmanned aerial vehicle with internal propulsion system and in this way analyze the air flow through an internal duct of the airfoil using computational fluid dynamics. The main objective is to evaluate the effect of the internal air flow past the airfoil and how this affects the aerodynamic performance by means of lift and drag forces. For this purpose, three different designs of the internal duct were studied; starting from the base 2415-3S airfoil developed in previous investigation, basing on the hypothesis of decreasing the flow separation produced when the propulsive airflow merges the external flow, and in this way obtaining the best configuration. For that purpose, an exhaustive study of the mesh sensitivity was performed. It was used a non-structured mesh since the computational domain is three-dimensional and complex. The selected mesh contains approximately 12.5 million elements. Both the computational domain and the numerical solution were made with commercial CAD and CFD software, respectively. Air, incompressible and steady was analyzed. The boundary conditions are in concordance with experimental setup in the AF 6109 wind tunnel. The k-e model is utilized to describe the turbulent flow process as followed in references. Results allowed obtaining velocity contours as well as lift and drag coefficients and also the location of separation and reattachment regions in some cases for zero degrees of angle of attack on the internal and external surfaces of the airfoil. Finally, the selection of the configuration with the best aerodynamic performance was made, selecting the option without curved baffles

    Eye Movement Abnormalities in Neurodegenerative Diseases

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    Neurodegenerative disorders consist in heterogeneous group of neurological conditions characterized by a wide spectrum of clinical features resulting from a progressive involvement of distinct neuron populations. Oculomotor abnormalities take a key place in the clinical picture of these disorders because the neurodegenerative processes involve the brain circuits of eye movements. The most common abnormalities include the saccadic dysfunction, fixation instability, and abnormal smooth pursuit. The clinical assessment of oculomotor function can help to differentiate diagnosis, while electrophysiological measures provide useful biomarkers for the understanding of disease physiopathology and progression. In this chapter, we review the state of the art of the eye movement’s deficits in some neurodegenerative diseases, such as Parkinson’s disease, Alzheimer’s disease, amyotrophic lateral sclerosis, Huntington’s disease, and the hereditary ataxias

    Consciousness as an emergent phenomenon: A tale of different levels of description

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    One of the biggest queries in cognitive sciences is the emergence of consciousness from matter. Modern neurobiological theories of consciousness propose that conscious experience is the result of interactions between large-scale neuronal networks in the brain, traditionally described within the realm of classical physics. Here, we propose a generalized connectionist framework in which the emergence of "conscious networks" is not exclusive of large brain areas, but can be identified in subcellular networks exhibiting nontrivial quantum phenomena. The essential feature of such networks is the existence of strong correlations in the system (classical or quantum coherence) and the presence of an optimal point at which the system's complexity and energy dissipation are maximized, whereas free-energy is minimized. This is expressed either by maximization of the information content in large scale functional networks or by achieving optimal efficiency through the quantum Goldilock effect.Fil: Guevara, Ramón. Università di Padova; Italia. Centre National de la Recherche Scientifique; Francia. Universite de Paris; FranciaFil: Mateos, Diego Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Matemática Aplicada del Litoral. Universidad Nacional del Litoral. Instituto de Matemática Aplicada del Litoral; Argentina. Universidad Autónoma de Entre Ríos; ArgentinaFil: Pérez Velázquez, José Luis. Ronin Institute; Estados Unido

    Bio-plausible digital implementation of a reward modulated STDP synapse

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    Reward-modulated Spike-Timing-Dependent Plasticity (R-STDP) is a learning method for Spiking Neural Network (SNN) that makes use of an external learning signal to modulate the synaptic plasticity produced by Spike-Timing-Dependent Plasticity (STDP). Combining the advantages of reinforcement learning and the biological plausibility of STDP, online learning on SNN in real-world scenarios can be applied. This paper presents a fully digital architecture, implemented on an Field-Programmable Gate Array (FPGA), including the R-STDP learning mechanism in a SNN. The hardware results obtained are comparable to the software simulations results using the Brian2 simulator. The maximum error is of 0.083 when a 14-bits fix-point precision is used in realtime. The presented architecture shows an accuracy of 95% when tested in an obstacle avoidance problem on mobile robotics with a minimum use of resources

    Pozzuolanic properties of the natural zeolites of some latin american deposits

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    This paper shows the results of the study of physical, mechanic and chemical behaviour of some natural zeolite types sampled in different outcrops of the world, mainly from Mexico, Cuba and Spain, as well as their incidence in certain practical applications, by means of the utilization of its pozzuolanic properties. Results emphasize that every natural zeolite variety gives different answers in the assays, probably influenced by the subtle variability of their chemical composition. Key words: zeolites, pozzuolanic, density, geometric, strengt

    Cluster Analysis of Finger-to-nose Test for Spinocerebellar Ataxia Assessment

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    El test Finger-to-nose test (FNT) es una evaluación neurológica para estudiar la coordinación. Se presenta una metodología de análisis de datos de FNT, que permite evaluar la evolución del estado de enfermos de Ataxia Espinocerebral de tipo 2 (SCA2), mediante técnicas de aprendizaje computacional.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
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