Search results for " Reflex"
showing 10 items of 241 documents
Crear y gestionar conocimiento en red: agentes y procesos implicados.
2013
El proposito de este articulo es delimitar las funciones y roles de los principales agentes y los procesos que intervienen en la creacion y gestion del conocimiento (CGC) en red desde una plataforma virtual. Recoge, al respecto, algunos de los resultados mas destacados que se derivan de la investigacion “Agentes y procesos en la gestion del conocimiento en red” (I+D+i). El proceso de investigacion seguido ha supuesto, fundamentalmente, la puesta en marcha de 5 redes de CGC desde una plataforma virtual (Moodle) sostenida en el debate como estrategia; tambien la realizacion de un trabajo de campo que considero un cuestionario de autodiagnostico para 15 directivos y especialistas en desarrollo…
Neuromuscular function during drop jumps in young and elderly males
2011
The Hoffman reflex (H-reflex), indicating alpha-motoneuron pool activity, has been shown to be task - and in resting conditions - age dependent. How aging affects H-reflex activity during explosive movements is not clear at present. The purpose of this study was to examine the effects of aging on H-reflexes during drop jumps, and its possible role in drop jump performance. Ten young (26.8 ± 2.7 years) and twenty elderly (64.2 ± 2.7 years) subjects participated in the study. Maximal drop jump performance and soleus H-reflex response (H/M jump) 20 ms after ground contact were measured in a sledge ergometer. Maximal H-reflex, maximal M-wave, Hmax/Mmax-ratio and H-reflex excitability curves wer…
Globalización, drogas y derechos humanos
2005
Cada día es mayor el número de persona, profesionales o no, que piden una reflexión abierta en la cuestión de las drogas y su legislación. Se entiende que el denominado "problema de las drogas" esta cargado no sólo de contradicciones, de tópicos y de intereses ocultos sino también de injusticias, exclusiones y sufrimientos de todo tipo. Estamos tan preocupados por la sustancia, que olvidamos los derechos más elementales de las personas implicadas en su consumo y su producción.
Electrophysiological brainstem testing in the diagnosis of reversible brainstem ischemia.
2002
The aim of this study was to evaluate the sensitivity of multimodal electrophysiological brainstem testing in the diagnosis of clinically suspected reversible ischemic deficits of the brainstem compared with diffusion weighted MR imaging. We investigated 158 consecutive patients presenting with signs of acute brainstem dysfunction. Serial electrophysiological brainstem tests including masseter reflex, blink reflex, masseter inhibitory reflex, AEP, MEP, EOG and the oculoauricular phenomenon were applied. In 14 of the 158 patients neurological deficits resolved in less than 24 hours, which was suggestive of a transitory ischemic attack (TIA), 19 patients had brainstem signs for more than 24 h…
Changes in muscle activity with increasing running speed.
2005
Electromyographic (EMG) activity of the leg muscles and the ground reaction forces were recorded in 17 elite male middle-distance runners, who performed isometric maximal voluntary contractions (MVC) as well as running at different speeds. Electromyograms were recorded from the gluteus maximus, vastus lateralis, biceps femoris, gastrocnemius and tibialis anterior. The results indicated that the averaged EMG (aEMG) activities of all the muscles studied increased (P < 0.05) with increasing running speed, especially in the pre-contact and braking phases. At higher speeds, the aEMG activities of the gastrocnemius, vastus lateralis, biceps femoris and gluteus maximus exceeded 100% MVC in these s…
Stretch-shortening cycle: a powerful model to study normal and fatigued muscle.
2000
Stretch-shortening cycle (SSC) in human skeletal muscle gives unique possibilities to study normal and fatigued muscle function. The in vivo force measurement systems, buckle transducer technique and optic fiber technique, have revealed that, as compared to a pure concentric action, a non-fatiguing SSC exercise demonstrates considerable performance enhancement with increased force at a given shortening velocity. Characteristic to this phenomenon is very low EMG-activity in the concentric phase of the cycle, but a very pronounced contribution of the short-latency stretch-reflex component. This reflex contributes significantly to force generation during the transition (stretch-shortening) pha…
Nociceptive Primitive Reflexes in Neurologically and Cognitively Healthy Aging Subjects
2019
ABSTRACT:Background:To assess the prevalence of three nociceptive primitive reflexes (nPR), i.e., glabellar tap, snout reflex, and palmomental reflex, in neurologically and cognitively healthy (NCH) aging subjects.Objective:To investigate whether nPR are cross-sectionally associated with white matter hyperintensities (WMH), lacunes, atrophy of the caudate nuclei, and global brain atrophy.Methods:A total of 1246 NCH subjects aged 45–91 years were included in the study and underwent standard brain MRI. Atrophy of the caudate nuclei and global brain atrophy were assessed through the bicaudate ratio (BCr) and lateral ventricles to brain ratio (LVBr), respectively. WMH were assessed through visu…
La Capilla de los Jurados revisitada: reflexiones pra una lectura arquitectónica
2014
Los límites de la intervención social. Investigación narrativa y mejora de la práctica profesional
2014
La tesis parte de la observación de una creciente dificultad de los servicios sociales para obtener resultados significativos en el campo de la pobreza y la exclusión social. Esta situación parece apuntar, una vez atendidas las razones de orden político y económico, a la posibilidad de que existan ciertos límites en la capacidad de la intervención social para modificar y mejorar los problemas sobre los que actúa. Dichos límites son comprendidos en primera instancia como un conjunto de datos que muestran que pese al incremento de la inversión en servicios de intervención social, la evolución de algunos indicadores de pobreza y exclusión no parecen mejorar en la extensión, intensidad y estabi…
Withdrawal reflex organisation to electrical stimulation of the dorsal foot in humans.
2001
The present study investigated excitatory reflex receptive fields for various muscle reflex responses and reflex mediated ankle joint movements using randomised electrical stimulation of the dorsal and plantar surface of the foot in 12 healthy subjects. Eleven electrodes (0.5-cm2 cathodes) were mounted on the dorsal side and three on the plantar side of the foot. A low (1.5 times pain threshold) and a high (2.3 times pain threshold) stimulus intensity were used to elicit the reflexes. EMG signals were recorded from tibialis anterior (TA), gastrocnemius medialis (GM), soleus (SO), biceps femoris (BF), and rectus femoris (RF) muscles together with the ankle movement measured by a goniometer. …