1,098 research outputs found

    Análisis de factores asociados a la participación en actividades recreativas de la comunidad universitaria del Tecnológico de Costa Rica: una estrategia recreativa

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    La recreación promueve el bienestar integral de las personas, tal beneficio se percibe a nivel mental, físico, social emocional y espiritual. En el plano universitario, las múltiples responsabilidades académicas y laborales disminuyen la posibilidad de participación en las diferentes actividades recreativas que se planifican. El objetivo del diagnóstico es determinar los motivos y limitaciones de participación recreativa que percibe la comunidad universitaria del Instituto Tecnológico de Costa Rica (TEC) en su Sede Central. El estudio cualitativo posee una muestra de 7 personas y el cuantitativo de 980 personas. El análisis de los datos se realizó mediante un grupo focal, dos entrevistas, una correlación de spearman, un análisis Chi-cuadrado y cuatro ANOVA de tres vías. Los resultados muestran que para la comunidad universitaria TEC, la principal motivación de participación recreativa en las mujeres es el factor dominio de competencia y en los hombres es el factor social. Por su parte, para la comunidad estudiantil fueron el intelectual y el dominio de competencia. En el caso de las limitaciones de participación, para las mujeres es el factor estructural y en la comunidad estudiantil fueron los factores interpersonales y estructurales. El proceso estratégico de la implementación del presente proyecto inicia dentro de la Feria de la Salud (FS) del TEC, pero pretende llegar a ser permanente, es por ello que considera aspectos como la misión, la visión, los objetivos, el diagnóstico (FODA) y la propuesta

    Neural Connectivity with Hidden Gaussian Graphical State-Model

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    The noninvasive procedures for neural connectivity are under questioning. Theoretical models sustain that the electromagnetic field registered at external sensors is elicited by currents at neural space. Nevertheless, what we observe at the sensor space is a superposition of projected fields, from the whole gray-matter. This is the reason for a major pitfall of noninvasive Electrophysiology methods: distorted reconstruction of neural activity and its connectivity or leakage. It has been proven that current methods produce incorrect connectomes. Somewhat related to the incorrect connectivity modelling, they disregard either Systems Theory and Bayesian Information Theory. We introduce a new formalism that attains for it, Hidden Gaussian Graphical State-Model (HIGGS). A neural Gaussian Graphical Model (GGM) hidden by the observation equation of Magneto-encephalographic (MEEG) signals. HIGGS is equivalent to a frequency domain Linear State Space Model (LSSM) but with sparse connectivity prior. The mathematical contribution here is the theory for high-dimensional and frequency-domain HIGGS solvers. We demonstrate that HIGGS can attenuate the leakage effect in the most critical case: the distortion EEG signal due to head volume conduction heterogeneities. Its application in EEG is illustrated with retrieved connectivity patterns from human Steady State Visual Evoked Potentials (SSVEP). We provide for the first time confirmatory evidence for noninvasive procedures of neural connectivity: concurrent EEG and Electrocorticography (ECoG) recordings on monkey. Open source packages are freely available online, to reproduce the results presented in this paper and to analyze external MEEG databases

    Sustentabilidad, eficiencia energética y niveles de iluminación para sistemas de alumbrado en edificios no residenciales

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    En este documento se hace un análisis energético para determinar la cantidad de energía eléctrica utilizada en los sistemas de alumbrado, en watts por metro cuadrado, en Edificios representativos de la Facultad de Ingeniería Mecánica y Eléctrica (FIME) y compararlo con lo recomendado por la normatividad vigente de nuestro país, de esta forma se pretende determinar una línea base para encontrar una mejor opción en cuanto a sistemas de alumbrado se refiere. Así mismo, se determina el nivel de iluminación en luxes de estos espacios para determinar si el espacio cuenta con un Nivel de Iluminación Satisfactorio o No satisfactorio (Insuficiente o Excesivo) de acuerdo a la normatividad vigente. Finalmente, se pretende identificar aquellos lugares que puedan disminuir los requerimientos de energía eléctrica y mejorar el sistema de iluminación en aras de la sustentabilidad

    Infecção pelo Sugarcane yellow leaf virus causa alterações na eficiência fotossintética e acúmulo de carboidratos nas folhas de cana-de-açúcar

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    Infection by Sugarcane yellow leaf virus (ScYLV) causes severe leaf symptoms in sugarcane (Saccharum spp.) hybrids, which indicate alterations in its photosynthetic apparatus. To gain an overview of the physiological status of infected plants, we evaluated chlorophyll a fluorescence and gas exchange assays, correlating the results with leaf metabolic surveys, i.e., photosynthetic pigments and carbohydrate contents. When compared to healthy plants, infected plants showed a reduction in potential quantum efficiency for photochemistry of photosystem (PSII) and alterations in the filling up of the plastoquinone (PQ) pool. They also showed reduction in the CO2 net exchange rates, probably as a consequence of impaired quantum yield. In addition, reductions were found in the contents of photosynthetic leaf pigments and in the ratio chlorophyll a/chlorophyll b (chla/chlb). Carbohydrate content in the leaves was increased as a secondary effect of the ScYLV infection. This article discusses the relation of virus replication and host defense responses with general alterations in the photosynthetic apparatus and in the metabolism of infected plants.O vírus do amarelecimento foliar da cana-de-açúcar (Sugarcane yellow leaf virus, ScYLV) causa sintomas foliares severos e típicos de infecção por luteovirus, em cana-de-açúcar (Saccharum spp.). Uma vez que alterações no sistema fotossintético da planta seriam esperadas, avaliaram-se a análise da emissão da fluorescência da clorofila a e as trocas gasosas durante a fotossíntese, relacionando esses dados com análises metabólicas, ou seja, conteúdos de pigmentos fotossintéticos e carboidratos presentes nas folhas. As plantas infetadas apresentaram redução na eficiência quântica fotoquímica potencial do fotossistema II (PSII) e alterações no preenchimento do pool de plastoquinona (PQ). Essas plantas apresentaram, também, redução nas taxas de troca líquida de CO2, provavelmente em conseqüência da redução na eficiência quântica. Paralelamente, reduções nos conteúdos de pigmentos fotossintéticos foliares e na razão clorofila a/clorofila b (chla/chlb) foram verificadas. Adicionalmente, o conteúdo de açúcares nas folhas foi aumentado, provavelmente como um efeito secundário da infecção viral. A relação entre a replicação viral e as respostas de defesa da hospedeira com as alterações encontradas no aparelho fotossintético e no metabolismo das plantas infetadas é discutida.101

    Mexican Banking Regulation: Evidence of the Appropriateness of Government Intervention

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    In this paper we investigate the validity of two assumptions frequently used to justify the transformation of the Mexican banking system through federal regulation. These assumptions are: (i) the alleged existence of economies of scale, and (ii) a homogeneous structure of the Mexican banking system. Econometric evidence from banking data over the period 1980 - 1982 suggests that neither of these assumptions are likely valid. The Mexican banking system is subject to constant rather than increasing returns to scale

    The Glial Cell of Human Cutaneous Sensory Corpuscles: Origin, Characterization, and Putative Roles

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    Sensory corpuscles of human skin are structures located at the peripheral end of the mechanoreceptive neurons and function as low-threshold mechanoreceptors (LTMRs). In its structure, in addition to the axon, there are glial cells, not myelinating, that are organized in different ways according to the morphotype of sensitive corpuscle, forming the so-called laminar cells of Meissner’s corpuscles, the laminar cells of the inner core of Pacinian corpuscles, or cells of the inner core in Ruffini’s corpuscles. Classically the glial cells of sensory corpuscles have been considered support cells and passive in the process of mechanotransduction. However, the presence of ion channels and synapses-like systems between them and the axon suggests that corpuscular glial cells are actively involved in the transformation of mechanical into electrical impulses. This chapter is an update on the origin, development, cytoarchitecture, and protein profile of glial cells of sensitive corpuscles especially those of human glabrous skin

    Afilado de azuela y cincel

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    Segunda unidad del bloque modular “Mecánica de minas” en la que se describen los materiales, métodos y herramientas para las labores de afilado manual de azuela, afilado con esmeril de azuela y cincel así como su uso apropiado.Second unit of the modular block "Mining Mechanics" in which the materials, methods and tools for manual grinding of azuela, grinding with grinding of azuela and chisel as well as its proper use are described.Usos de la azuela, cincel,galgas y plantillas -- El esmeril. partes, usos y características -- Procedimiento para el afilado de la azuela -- Procedimiento para el afilado del cincelPrimera ediciónnaCartillas del bloque modular “Mecánica de minas”: 1 Afilado y trabado manual de serrucho y trocero 2 Afilado de azuela y cincel. 3. Aserrado manual de tubería 4. Roscado exterior de tubería con terraja 5. Acoplamiento y recuperación de tubería de aire comprimido en la mina 6. Fijación de acople a la manguera para aire comprimido 7. Acoplamiento de mangueras para aire comprimido 8. Unión de mangueras 9. Mantenimiento de un martillo picador 10. Lubricación automática de un martillo picador 11. Forjado, temple y revenido a la pica del martillo picador 12 Mantenimiento de un soporte neumático 13 Mantenimiento de un martillo perforador 14 Construcción de un estrobo con cable de acero 15. Instalación de un malacate en la mina 16 Mantenimiento de un malacate neumatico 17. Mantenimiento de ruedas de una vagoneta 18. Unión de una cinta transportadora con agrafes y platinas 19. Centrado y tensión de una cinta transportadora 20. Mantenimiento de una transportadora de cinta 21. Nivelación de una bomba centrífuga 22. Mantenimiento de una bomba centrifuga 23. Mantenimiento de un ventilador neumático69 página

    Bragg Peak Localization with Piezoelectric Sensors for Proton Therapy Treatment

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    [EN] A full chain simulation of the acoustic hadrontherapy monitoring for brain tumours is presented in this work. For the study, a proton beam of 100 MeV is considered. In the first stage, Geant4 is used to simulate the energy deposition and to study the behaviour of the Bragg peak. The energy deposition in the medium produces local heating that can be considered instantaneous with respect to the hydrodynamic time scale producing a sound pressure wave. The resulting thermoacoustic signal has been subsequently obtained by solving the thermoacoustic equation. The acoustic propagation has been simulated by FEM methods in the brain and the skull, where a set of piezoelectric sensors are placed. Last, the final received signals in the sensors have been processed in order to reconstruct the position of the thermal source and, thus, to determine the feasibility and accuracy of acoustic beam monitoring in hadrontherapy.This research received was funded by the Spanish Agencia Estatal de Investigacion, grant numbers FPA2015-65150-C3-2-P (MINECO/FEDER) and PGC2018-096663-B-C43 (MCIU/FEDER).Otero-Vega, JE.; Felis-Enguix, I.; Herrero Debón, A.; Merchán, JA.; Ardid Ramírez, M. (2020). Bragg Peak Localization with Piezoelectric Sensors for Proton Therapy Treatment. Sensors. 20(10):1-12. https://doi.org/10.3390/s20102987S1122010A population-based assessment of proton beam therapy utilization in California. (2020). The American Journal of Managed Care, 26(2), e28-e35. doi:10.37765/ajmc.2020.42398Dutz, A., Agolli, L., Bütof, R., Valentini, C., Baumann, M., Lühr, A., … Krause, M. (2020). Neurocognitive function and quality of life after proton beam therapy for brain tumour patients. Radiotherapy and Oncology, 143, 108-116. doi:10.1016/j.radonc.2019.12.024Lesueur, P., Calugaru, V., Nauraye, C., Stefan, D., Cao, K., Emery, E., … Thariat, J. (2019). Proton therapy for treatment of intracranial benign tumors in adults: A systematic review. Cancer Treatment Reviews, 72, 56-64. doi:10.1016/j.ctrv.2018.11.004Amaldi, U., Bonomi, R., Braccini, S., Crescenti, M., Degiovanni, A., Garlasché, M., … Zennaro, R. (2010). Accelerators for hadrontherapy: From Lawrence cyclotrons to linacs. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 620(2-3), 563-577. doi:10.1016/j.nima.2010.03.130Weber, D. C., Abrunhosa-Branquinho, A., Bolsi, A., Kacperek, A., Dendale, R., Geismar, D., … Grau, C. (2017). Profile of European proton and carbon ion therapy centers assessed by the EORTC facility questionnaire. 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Ultrasonic wave propagation in human cancellous bone: Application of Biot theory. The Journal of the Acoustical Society of America, 116(1), 61-73. doi:10.1121/1.1755239Raffaele, L. (2016). Advances in hadrontherapy dosimetry. Physica Medica, 32, 187. doi:10.1016/j.ejmp.2016.07.323Dosanjh, M., Amaldi, U., Mayer, R., & Poetter, R. (2018). ENLIGHT: European network for Light ion hadron therapy. Radiotherapy and Oncology, 128(1), 76-82. doi:10.1016/j.radonc.2018.03.014Ahmad, M., Xiang, L., Yousefi, S., & Xing, L. (2015). Theoretical detection threshold of the proton-acoustic range verification technique. Medical Physics, 42(10), 5735-5744. doi:10.1118/1.4929939Smith, A., Gillin, M., Bues, M., Zhu, X. R., Suzuki, K., Mohan, R., … Matsuda, K. (2009). The M. D. Anderson proton therapy system. Medical Physics, 36(9Part1), 4068-4083. doi:10.1118/1.3187229Yock, T. I., & Tarbell, N. J. (2004). Technology Insight: proton beam radiotherapy for treatment in pediatric brain tumors. 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