176 research outputs found

    Monitorización de las cargas de entrenamiento en corredores de fondo y medio fondo de alto nivel

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    El principal objetivo del entrenamiento consiste en mejorar el rendimiento y, por ende, reducir lesiones. Para ello, la monitorización de dicha carga (interna, externa y su relación) se ha constatado como vital. Sin embargo, muchos entrenadores siguen sin controlar (o etéreamente) las cargas en sus deportistas, pues, además, no existe un sistema etiquetado como el ideal. Consecuentemente, teniendo en cuenta el contexto y lo que la literatura dice al respecto, se realizó una propuesta personal con corredores de resistencia de alto nivel, contabilizando, en cuanto a carga externa, volumen mediante los kilómetros recorridos semanalmente, intensidad mediante la velocidad de carrera con zonas de entrenamiento en función del perfil individual de lactato, y frecuencia registrando el número de entrenamientos y de los contenidos trabajados. Respecto al estrés interno, la Escala de Esfuerzo Percibido y la medición de la altura del salto vertical con contramovimiento, en pos de determinar la fatiga neuromuscular subaguda. Los resultados mostraron relación significativa en la mayoría de variables, haciendo que el objetivo e hipótesis que perseguía la intervención se cumplan en mayor o menor medida, por lo que el sistema de monitorización escogido y/o los diferentes ítems que lo componen podrían ser válidos para su utilización en otros contextos.The main objective of training is to improve performance and, therefore, reduce injuries. For that reason, the monitoring of this load (internal, external and their relationship) has been verified as vital. However, many trainers still do not control (or ethereally) the loads on their athletes. In addition, there is not system labeled as the ideal. Consequently, taking into account the context and what the literature says about it, a personal research was made with high-level resistance runners, accounting, in terms of external load, volume through the kilometers traveled weekly, intensity through the running speed with training zones depending on the individual lactate profile, and frequency recording the number of training sessions and the contents worked. Regarding internal stress, the Rating of Perceived Exertion and a measurement of countermovement jump height, in order to determine subacute neuromuscular fatigue. The results showed a significant relationship in most variables, making the objective and hypothesis of the intervention have been met to a greater or lesser extent, so that the chosen monitoring system and / or the different items that comprise it could be valid for its use in other contexts.info:eu-repo/semantics/publishedVersio

    Análisis del golpeo y la preparación psicológica para retornar a la práctica en futbolistas tras una lesión isquiosural

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    Las lesiones de la musculatura isquiosural son las más comunes en fútbol, y pueden presentar efectos residuales que cambien el patrón de un gesto técnico. El presente estudio analizó las diferencias en la técnica de golpeo entre jugadores anteriormente lesionados y jugadores no lesionados, así como las correlaciones entre la capacidad psicológica para retornar a la práctica y las características del gesto. Tres futbolistas que habían padecido una lesión de isquiosurales conformaron el grupo de jugadores anteriormente lesionados, y tres futbolistas que no habían padecido ninguna lesión en el miembro inferior en los últimos dos años, formaron el grupo de jugadores no lesionados. Se analizaron los gestos de golpeo a balón parado y de golpeo en carrera a través del programa Kinovea. Asimismo, se evaluó la capacidad psicológica para retornar a la práctica mediante el Injury Psychological Readiness to Return to Sport (I-PRRS). Únicamente la velocidad del balón en el golpeo en carrera presentó diferencias significativas entre grupos (p<0,05). Además, se obtuvieron correlaciones positivas entre la preparación psicológica para retornar y la flexión de rodilla en el golpeo en carrera, y entre la flexión de rodilla en el golpeo a balón parado y los ítems 3 y 4 del I-PRRS. Asimismo, se hallaron correlaciones negativas entre la extensión de cadera en el golpeo a balón parado y el ítem 6 del I-PRRS. Los resultados permiten concluir que variables cinemáticas y variables psicológicas se encuentran interrelacionadas tras una lesión en la musculatura isquiosural.info:eu-repo/semantics/publishedVersio

    Exploiting transmission spatial diversity in frequency selective systems with feedback channel

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    In this paper we address the design of a multiple transmit antenna system in which the Channel State Information (CSI) at the transmitter is not perfect. Two different approaches are analyzed one based on the Minimization of the Mean Square Error (MMSEj and the other based on the application of the Maximum Likelihood Sequence Estimation (MLSE). In both cases a Bayesian criterion is used in order to take into account the error between the CSI and the real channel. Finally, some simulation results and conclusions are provided, showing which is the gain of these approaches when the error between the CSI and the real channel is either Gaussian or uniform, where this last case corresponds to a quantization of the channel time response in order to transmit the CSI through a feedback channel from the receiver to the transmitter.Postprint (published version

    Simulated annealing techniques for joint transmitter-receiver design in a multiple user access MIMO-OFDM channel

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    In this paper we consider the problem of the joint design of multiple transmitters and receivers in a MIMe- eFDM scenario. We consider that both the transmitters and receivers have multiple antennas, configuring a Multi-Input-Multi-Output (MIMe) channel. Based on this structure, space diversity techniques can be used to separate the signals transmitted by different users. Concretely, the proposed approach consists in beamforming at both sides of the system, combined with the Orthogonal-Frequency-Division-Multiplexing (eFDM) modulation. The goal is the minimization of the total transmitted power subject to constraints related to the Quality of Service (QoS) for each user in terms of the Bit Error Rate (BER) and the maximum transmitted power for some terminals. By making use of this approach, the Multiple Access Interference (MAI) is minimized and the physical resources are exploited in an optimum way. The design is based on Simulated Annealing (SA), an heuristic technique able to find the optimum design in this non-convex problem and that can take into account all kind of constraints.Postprint (published version

    A robust maximin approach for MIMO communications with imperfect channel state information based on convex optimization

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    This paper considers a wireless communication system with multiple transmit and receive antennas, i.e., a multiple-input-multiple-output (MIMO) channel. The objective is to design the transmitter according to an imperfect channel estimate, where the errors are explicitly taken into account to obtain a robust design under the maximin or worst case philosophy. The robust transmission scheme is composed of an orthogonal space–time block code (OSTBC), whose outputs are transmitted through the eigenmodes of the channel estimate with an appropriate power allocation among them. At the receiver, the signal is detected assuming a perfect channel knowledge. The optimization problem corresponding to the design of the power allocation among the estimated eigenmodes, whose goal is the maximization of the signal-to-noise ratio (SNR), is transformed to a simple convex problem that can be easily solved. Different sources of errors are considered in the channel estimate, such as the Gaussian noise from the estimation process and the errors from the quantization of the channel estimate, among others. For the case of Gaussian noise, the robust power allocation admits a closed-form expression. Finally, the benefits of the proposed design are evaluated and compared with the pure OSTBC and nonrobust approaches.Postprint (published version

    Flexible MIMO architectures: guidelines in the design of MIMO parameters

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    One of the multiple advantages of communicating through MIMO systems is their inherent ability to provide flexible configurations. Following this line of thought, in this paper we present a generic framework to study the degrees of freedom in the design of MIMQ communication systems (e.g.: code length, number of multiplexed streams, or receiver structure). Precisely, we focus our efforts to bridge the gap between the design of MIMO systems with full and no channel state information at the transmitter side and also with different complexiry degrees at ihe receiver side. For instance, we can establish a trade-off, not only between the achievable rates and the diversity or beamforming gains, but also between the rate and the robustness to uncertainties in the channel state information.Postprint (published version

    TracEDaaS: Captura y Trazabilidad de Artefactos del Proceso de Diseño

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    Se presenta una herramienta, TracEDaaS, que permite la captura y la trazabilidad de la evolución de los productos del proceso de diseño de software, soportando el refinamiento y la elaboración iterativa del mismo. TracEDaaS ha sido implementada como un servicio en la nube bajo el modelo “Software as a Service” (SaaS) y permite representar junto a las versiones de los objetos del diseño, información que permite la trazabilidad de los artefactos del proceso de desarrollo, manteniendo la navegabilidad entre los distintos modelos y las diferentes versiones de los mismos. Esta información está estructurada en término de las operaciones aplicadas a los objetos de diseño. La herramienta es lo suficientemente flexible para soportar nuevos problemas de diseño en término de los conceptos particulares del dominio y las posibles operaciones que pueden ser aplicadas a las instancias de tales conceptos.Fil: Hernandez, Federico. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Santa Fe; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Roldán, María Luciana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo y Diseño. Universidad Tecnológica Nacional. Facultad Regional Santa Fe. Instituto de Desarrollo y Diseño; ArgentinaFil: Vegetti, Maria Marcela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo y Diseño. Universidad Tecnológica Nacional. Facultad Regional Santa Fe. Instituto de Desarrollo y Diseño; ArgentinaFil: Gonnet, Silvio Miguel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo y Diseño. Universidad Tecnológica Nacional. Facultad Regional Santa Fe. Instituto de Desarrollo y Diseño; ArgentinaFil: Leone, Horacio Pascual. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo y Diseño. Universidad Tecnológica Nacional. Facultad Regional Santa Fe. Instituto de Desarrollo y Diseño; Argentin

    Mendelian Randomisation Confirms the Role of Y-Chromosome Loss in Alzheimer’s Disease Aetiopathogenesis in Men

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    Mosaic loss of chromosome Y (mLOY) is a common ageing-related somatic event and has been previously associated with Alzheimer’s disease (AD). However, mLOY estimation from genotype microarray data only reflects the mLOY degree of subjects at the moment of DNA sampling. Therefore, mLOY phenotype associations with AD can be severely age-confounded in the context of genome-wide association studies. Here, we applied Mendelian randomisation to construct an age-independent mLOY polygenic risk score (mloy-PRS) using 114 autosomal variants. The mloy-PRS instrument was associated with an 80% increase in mLOY risk per standard deviation unit (p = 4.22 × 10−20) and was orthogonal with age. We found that a higher genetic risk for mLOY was associated with faster progression to AD in men with mild cognitive impairment (hazard ratio (HR) = 1.23, p = 0.01). Importantly, mloy-PRS had no effect on AD conversion or risk in the female group, suggesting that these associations are caused by the inherent loss of the Y chromosome. Additionally, the blood mLOY phenotype in men was associated with increased cerebrospinal fluid levels of total tau and phosphorylated tau181 in subjects with mild cognitive impairment and dementia. Our results strongly suggest that mLOY is involved in AD pathogenesis.P.G.-G. (Pablo García-González) is supported by CIBERNED employment plan CNV-304-PRF-866. CIBERNED is integrated into ISCIII (Instituto de Salud Carlos III). I.d.R is supported by a national grant from the Instituto de Salud Carlos III FI20/00215. A.C. (Amanda Cano) acknowledges the support of the Spanish Ministry of Science, Innovation, and Universities under the grant Juan de la Cierva (FJC2018-036012-I). M.B. (Mercé Boada) and A.R. (Agustín Ruiz) are also supported by national grants PI13/02434, PI16/01861, PI17/01474, PI19/01240, and PI19/01301. The Genome Research @ Fundació ACE project (GR@ACE) is supported by Grifols SA, Fundación bancaria “La Caixa”, Fundació ACE, and CIBERNED. Acción Estratégica en Salud is integrated into the Spanish National R + D + I Plan and funded by ISCIII (Instituto de Salud Carlos III)—Subdirección General de Evaluación—and the Fondo Europeo de Desarrollo Regional (FEDER—“Una manera de hacer Europa”). Genotyping of the ACE MCI-EADB samples was performed in the context of EADB (European Alzheimer DNA biobank) funded by the JPco-fuND FP-829-029 (ZonMW project number 733051061). This work was supported by a grant (European Alzheimer DNA BioBank, EADB) from the EU Joint Program—Neurodegenerative Disease Research (JPND). Partial funding for open access charge: Universidad de Málag

    Differentiation stage of myeloma plasma cells: biological and clinical significance

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    [EN] The notion that plasma cells (PCs) are terminally differentiated has prevented intensive research in multiple myeloma (MM) about their phenotypic plasticity and differentiation. Here, we demonstrated in healthy individuals (n = 20) that the CD19 − CD81 expression axis identifies three bone marrow (BM)PC subsets with distinct age-prevalence, proliferation, replication-history, immunoglobulin-production, and phenotype, consistent with progressively increased differentiation from CD19+CD81+ into CD19 − CD81+ and CD19 − CD81 − BMPCs. Afterwards, we demonstrated in 225 newly diagnosed MM patients that, comparing to normal BMPC counterparts, 59% had fully differentiated (CD19 − CD81 −) clones, 38% intermediate-differentiated (CD19 − CD81+) and 3% less-differentiated (CD19+CD81+) clones. The latter patients had dismal outcome, and PC differentiation emerged as an independent prognostic marker for progression-free (HR: 1.7; P = 0.005) and overall survival (HR: 2.1; P = 0.006). Longitudinal comparison of diagnostic vs minimal-residual-disease samples (n = 40) unraveled that in 20% of patients, less-differentiated PCs subclones become enriched after therapy-induced pressure. We also revealed that CD81 expression is epigenetically regulated, that less-differentiated clonal PCs retain high expression of genes related to preceding B-cell stages (for example: PAX5), and show distinct mutation profile vs fully differentiated PC clones within individual patients. Together, we shed new light into PC plasticity and demonstrated that MM patients harbouring less-differentiated PCs have dismal survival, which might be related to higher chemoresistant potential plus different molecular and genomic profiles

    Clinical and structural brain correlates of hypomimia in early-stage Parkinson's disease

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    Altres ajuts: acord transformatiu CRUE-CSICBackground and purpose: Reduced facial expression of emotions is a very frequent symptom of Parkinson's disease (PD) and has been considered part of the motor features of the disease. However, the neural correlates of hypomimia and the relationship between hypomimia and other non-motor symptoms of PD are poorly understood. Methods: The clinical and structural brain correlates of hypomimia were studied. For this purpose, cross-sectional data from the COPPADIS study database were used. Age, disease duration, levodopa equivalent daily dose, Unified Parkinson's Disease Rating Scale part III (UPDRS-III), severity of apathy and depression and global cognitive status were collected. At the imaging level, analyses based on gray matter volume and cortical thickness were used. Results: After controlling for multiple confounding variables such as age or disease duration, the severity of hypomimia was shown to be indissociable from the UPDRS-III speech and bradykinesia items and was significantly related to the severity of apathy (β = 0.595; p < 0.0001). At the level of neural correlates, hypomimia was related to motor regions brodmann area 8 (BA 8) and to multiple fronto-temporo-parietal regions involved in the decoding, recognition and production of facial expression of emotions. Conclusion: Reduced facial expressivity in PD is related to the severity of symptoms of apathy and is mediated by the dysfunction of brain systems involved in motor control and in the recognition, integration and expression of emotions. Therefore, hypomimia in PD may be conceptualized not exclusively as a motor symptom but as a consequence of a multidimensional deficit leading to a symptom where motor and non-motor aspects converge
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