Resultados clásicos sobre el rango de funciones analíticas

Se han recogido algunos resultados clásicos sobre la imagen de una función analítica. En la primera parte del trabajo se presentan los teoremas de Bloch y de Ahlfors, estos resultados estudian el valor del radio del mayor disco que se puede encontrar en la imagen de cualquier función holomorfa. Más adelante se estudian las funciones enteras y aparece el teorema pequeño de Picard, uno de los teoremas más importantes de la teoría de funciones. Finalmente, con la ayuda del teorema de Schottky, se presenta el teorema grande de Picard. Este teorema estudia el comportamiento de una función holomorfa en el entorno de un singularidad esencial

Técnicas de aprendizaje estadístico en modelos de valoración dinámica de precios

En el presente trabajo se estudian diversas técnicas de aprendizaje por refuerzo con la idea de solucionar varios problemas de fijación y planificación de precios. Para ello, se lleva a cabo una introducción al aprendizaje por refuerzo, estudiando los problemas de decisión de Markov en el caso de un único agente. En estos juegan un papel fundamental las ecuaciones de optimalidad de Bellman, que permiten el desarrollo de métodos para la resolución del problema. En el trabajo se verán los algoritmos Q-Learning, SARSA y dos de sus variantes. En el caso de varios agentes se estudian los juegos matriciales y su generalización a varios estados, los juegos estocásticos. En estos problemas, y bajo el soporte de la teoría de juegos, aparecen los equilibrios de Nash. Veremos dos de las principales técnicas para resolver estos problemas, los métodos de mejor respuesta y los métodos de los equilibrios. Finalmente se analizarán los resultados obtenidos tras aplicar los algoritmos estudiados a problemas de fijación de precios.<br /

Combined Transcranial Direct Current Stimulation and Virtual Reality-Based Paradigm for Upper Limb Rehabilitation in Individuals with Restricted Movements. A Feasibility Study with a Chronic Stroke Survivor with Severe Hemiparesis

[EN] Impairments of the upper limb function are a major cause of disability and rehabilitation. Most of the available therapeutic options are based on active exercises and on motor and attentional inclusion of the affected arm in task oriented movements. However, active movements may not be possible after severe impairment of the upper limbs. Different techniques, such as mirror therapy, motor imagery, and non-invasive brain stimulation have been shown to elicit cortical activity in absence of movements, which could be used to preserve the available neural circuits and promote motor learning. We present a virtual reality-based paradigm for upper limb rehabilitation that allows for interaction of individuals with restricted movements from active responses triggered when they attempt to perform a movement. The experimental system also provides multisensory stimulation in the visual, auditory, and tactile channels, and transcranial direct current stimulation coherent to the observed movements. A feasibility study with a chronic stroke survivor with severe hemiparesis who seemed to reach a rehabilitation plateau after two years of its inclusion in a physical therapy program showed clinically meaningful improvement of the upper limb function after the experimental intervention and maintenance of gains in both the body function and activity. The experimental intervention also was reported to be usable and motivating. Although very preliminary, these results could highlight the potential of this intervention to promote functional recovery in severe impairments of the upper limb.This study was funded in part by Ministerio de Economia y Competitividad of Spain (Project TIN2014-61975-EXP and Grant BES-2014-068218) and by Universitat Politecnica de Valencia (Grant PAID-10-14 and Grant PAID-10-16).Fuentes Calderón, MA.; Borrego, A.; Latorre Grau, J.; Colomer Font, C.; Alcañiz Raya, ML.; Sánchez-Ledesma, MJ.; Noé-Sebastián, E.... (2018). Combined Transcranial Direct Current Stimulation and Virtual Reality-Based Paradigm for Upper Limb Rehabilitation in Individuals with Restricted Movements. A Feasibility Study with a Chronic Stroke Survivor with Severe Hemiparesis. Journal of Medical Systems. 42(5):1-9. https://doi.org/10.1007/s10916-018-0949-yS19425Invernizzi, M., Negrini, S., Da, S. C., Lanzotti, L., Cisari, C., and Baricich, A., The value of adding mirror therapy for upper limb motor recovery of subacute stroke patients: A randomized controlled trial. Eur. J. Phys. Rehabil. Med. 49:311–317, 2013.Park, Y., Chang, M., Kim, K.-M., and An, D.-H., The effects of mirror therapy with tasks on upper extremity function and self-care in stroke patients. J. Phys. Ther. Sci. 27:1499–1501, 2015. https://doi.org/10.1589/jpts.27.1499 .Pollock, A., Farmer, S. E., Brady, M. C., Langhorne, P., Mead, G. E., Mehrholz, J., and van Wijck, F., Interventions for improving upper limb function after stroke. Cochrane Database Syst. Rev. 11, 2014. https://doi.org/10.1002/14651858.CD010820.pub2 .Barker, R. N., Gill, T. J., and Brauer, S. G., Factors contributing to upper limb recovery after stroke: A survey of stroke survivors in Queensland Australia. Disabil. Rehabil. 29:981–989, 2007. https://doi.org/10.1080/09638280500243570 .Bayona, N. 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Psychiatry. 82:393–398, 2011. https://doi.org/10.1136/jnnp.2009.194134 .Gatti, R., Rocca, M. A., Fumagalli, S., Cattrysse, E., Kerckhofs, E., Falini, A., and Filippi, M., The effect of action observation/execution on mirror neuron system recruitment: an fMRI study in healthy individuals. Brain Imaging Behav. 11:565–576, 2017. https://doi.org/10.1007/s11682-016-9536-3 .Bonato, C., Miniussi, C., and Rossini, P. M., Transcranial magnetic stimulation and cortical evoked potentials: A TMS/EEG co-registration study. Clin. Neurophysiol. 117:1699–1707, 2006. https://doi.org/10.1016/j.clinph.2006.05.006 .Grundmann, L., Rolke, R., Nitsche, M. A., Pavlakovic, G., Happe, S., Treede, R. D., Paulus, W., and Bachmann, C. G., Effects of transcranial direct current stimulation of the primary sensory cortex on somatosensory perception. Brain Stimul. 4:253–260, 2011. https://doi.org/10.1016/j.brs.2010.12.002 .von Rein, E., Hoff, M., Kaminski, E., Sehm, B., Steele, C. J., Villringer, A., and Ragert, P., Improving motor performance without training: the effect of combining mirror visual feedback with transcranial direct current stimulation. J. Neurophysiol. 113:2383–2389, 2015. https://doi.org/10.1152/jn.00832.2014 .Kim, Y. J., Ku, J., Cho, S., Kim, H. J., Cho, Y. K., Lim, T., and Kang, Y. J., Facilitation of corticospinal excitability by virtual reality exercise following anodal transcranial direct current stimulation in healthy volunteers and subacute stroke subjects. J. Neuroeng. Rehabil. 11:124, 2014. https://doi.org/10.1186/1743-0003-11-124 .S. Bermúdez i Badia, G.G. Fluet, R. Llorens, J.E. Deutsch, Virtual Reality for Sensorimotor Rehabilitation Post Stroke: Design Principles and Evidence. In: Neurorehabilitation Technol., Second edi, Springer, 2016: pp. 573–603. https://doi.org/10.1007/978-3-319-28603-7_28 .Im, H., Ku, J., Kim, H. J., and Kang, Y. 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Merlo, M.A. Minetto, Technology and instrumentation for detection and conditioning of the surface electromyographic signal: State of the art, Clin. Biomech. 24 (2009) 122–134. https://doi.org/10.1016/j.clinbiomech.2008.08.006 .Trojano, L., Moretta, P., Loreto, V., Cozzolino, A., Santoro, L., and Estraneo, A., Quantitative assessment of visual behavior in disorders of consciousness. J. Neurol. 259:1888–1895, 2012. https://doi.org/10.1007/s00415-012-6435-4 .Trojano, L., Moretta, P., Loreto, V., Santoro, L., and Estraneo, A., Affective saliency modifies visual tracking behavior in disorders of consciousness: A quantitative analysis. J. Neurol. 260:306–308, 2013. https://doi.org/10.1007/s00415-012-6717-x .Sanford, J., Moreland, J., Swanson, L. R., Stratford, P. W., and Gowland, C., Reliability of the Fugl-Meyer assessment for testing motor performance in patients following stroke. Phys. Ther. 73:447–454, 1993. https://doi.org/10.1177/1545968304269210 .Lang, C. E., Edwards, D. 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Pasados y presente. Estudios para el profesor Ricardo García Cárcel

Ricardo García Cárcel (Requena, 1948) estudió Historia en Valencia bajo el magisterio de Joan Reglà, con quien formó parte del primer profesorado de historia moderna en la Universidad Autónoma de Barcelona. En esta universidad, desde hace prácticamente cincuenta años, ha desarrollado una extraordinaria labor docente y de investigación marcada por un sagaz instinto histórico, que le ha convertido en pionero de casi todo lo que ha estudiado: las Germanías, la historia de la Cataluña moderna, la Inquisición, las culturas del Siglo de Oro, la Leyenda Negra, Felipe II, Felipe V, Austrias y Borbones, la guerra de la Independencia, la historia cultural, los mitos de la historia de España... Muy pocos tienen su capacidad para reflexionar, ordenar, analizar, conceptualizar y proponer una visión amplia y llena de matices sobre el pasado y las interpretaciones historiográficas. A su laboriosidad inimitable se añade una dedicación sin límites en el asesoramiento de alumnos e investigadores e impulsando revistas, dosieres, seminarios o publicaciones colectivas. Una mínima correspondencia a su generosidad lo constituye este volumen a manera de ineludible agradecimiento

Arousal Detection in Elderly People from Electrodermal Activity Using Musical Stimuli

The detection of emotions is fundamental in many areas related to health and well-being. This paper presents the identification of the level of arousal in older people by monitoring their electrodermal activity (EDA) through a commercial device. The objective was to recognize arousal changes to create future therapies that help them to improve their mood, contributing to reduce possible situations of depression and anxiety. To this end, some elderly people in the region of Murcia were exposed to listening to various musical genres (flamenco, Spanish folklore, Cuban genre and rock/jazz) that they heard in their youth. Using methods based on the process of deconvolution of the EDA signal, two different studies were carried out. The first, of a purely statistical nature, was based on the search for statistically significant differences for a series of temporal, morphological, statistical and frequency features of the processed signals. It was found that Flamenco and Spanish Folklore presented the highest number of statistically significant parameters. In the second study, a wide range of classifiers was used to analyze the possible correlations between the detection of the EDA-based arousal level compared to the participants&rsquo; responses to the level of arousal subjectively felt. In this case, it was obtained that the best classifiers are support vector machines, with 87% accuracy for flamenco and 83.1% for Spanish Folklore, followed by K-nearest neighbors with 81.4% and 81.5% for Flamenco and Spanish Folklore again. These results reinforce the notion of familiarity with a musical genre on emotional induction

Support vector machines for explaining physiological stress response in Wood mice (Apodemus sylvaticus)

Abstract Physiological stress response is a crucial adaptive mechanism for prey species survival. This paper aims to identify the main environmental and/or individual factors better explaining the stress response in Wood mice, Apodemus sylvaticus. We analyzed alterations in fecal glucocorticoid metabolite (FCM) concentration – extensively used as an accurate measure of the physiological stress response – of wild mice fecal samples seasonally collected during three years. Then, support vector machines were built to predict said concentration according to different stressors. These statistical tools appear to be particularly suitable for small datasets with substantial number of dimensions, corroborating that the stress response is an extremely complex process in which multiple factors can simultaneously partake in a context-dependent manner, i.e., the role of each potential stressor varies in time depending on other stressors. However, air-humidity, temperature and body-weight allowed us to explain the FCM fluctuation in 98% of our samples. The relevance of air-humidity and temperature altering FCM level could be linked to the presence of an abundant vegetation cover and, therefore, to food availability and predation risk perception. Body-weight might be related to the stress produced by reproduction and other intraspecific relationships such as social dominance or territorial behavior

Desarrollo y validación de un sistema de posturografía online empleando plataformas de presión de bajo coste

Noé, E.; Llorens Rodríguez, R.; Colomer, C.; Grau Latorre, J.; Verdecho, I.; Baldoví, A.; Rodríguez, C.... (2016). Desarrollo y validación de un sistema de posturografía online empleando plataformas de presión de bajo coste. Revista de Neurologia. 62(5):235-235. http://hdl.handle.net/10251/81834S23523562

Documento de revisión y actualización de la cefalea por uso excesivo de medicación (CUEM)

Introducción: La cefalea con uso excesivo de medicación es una cefalea secundaria en la que el uso regular o frecuente de medicación analgésica produce un aumento de la frecuencia de una cefalea de base, pasando de episódica a crónica. La prevalencia de esta entidad está en tornoal 1-2%, siendo más frecuente en mujeres entre 30 y 50 a ̃nos con comorbilidades psiquiátricas como depresión o ansiedad y otros procesos de dolor crónico. Es importante conocer el manejo de esta entidad. Por este motivo, el Grupo de Estudios de Cefaleas de la Sociedad Española de Neurología ha pretendido realizar este documento de consenso sobre esta patología. Desarrollo: Esta guía ha sido redactada por un grupo de expertos a partir de la revisión dela evidencia científica publicada y estableciendo recomendaciones prácticas para su adecuado manejo y tratamiento. El tratamiento de la cefalea con uso excesivo de medicación tiene varios pilares fundamentales y suele ser complejo: información y educación sobre el desarrollo de la cefalea con uso excesivo de medicación, tratamiento preventivo, suspensión del fármaco de uso frecuente y tratamiento de deshabituación. Es importante el seguimiento de pacientes con riesgo de recurrencias. Conclusiones: Esperamos que este documento resulte de utilidad y permita su aplicación práctica en la consulta diaria y que sirva para actualizar y mejorar el conocimiento del manejo de esta patología

Calcitonin gene-related peptide in migraine : from pathophysiology to treatment CGRP en migraña: de la fisiopatología a la terapéutica

It has been observed in recent years that levels of such molecules as calcitonin gene-related peptide (CGRP) and, to a lesser extent, the pituitary adenylate cyclase-activating peptide are elevated during migraine attacks and in chronic migraine, both in the cerebrospinal fluid and in the serum. Pharmacological reduction of these proteins is clinically significant, with an improvement in patients' migraines. It therefore seems logical that one of the main lines of migraine research should be based on the role of CGRP in the pathophysiology of this entity. The Spanish Society of Neurology's Headache Study Group decided to draft this document in order to address the evidence on such important issues as the role of CGRP in the pathophysiology of migraine and the mechanism of action of monoclonal antibodies and gepants; and to critically analyse the results of different studies and the profile of patients eligible for treatment with monoclonal antibodies, and the impact in terms of pharmacoeconomics. The clinical development of gepants, which are CGRP antagonists, for the acute treatment of migraine attacks, and CGRP ligand and receptor monoclonal antibodies offer promising results for these patients