948 resultados para Frontal-parietal Axis
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Among the external manifestations of scoliosis, the rib hump, which is associated with the ribs' deformities and rotations, constitutes the most disturbing aspect of the scoliotic deformity for patients. A personalized 3-D model of the rib cage is important for a better evaluation of the deformity, and hence, a better treatment planning. A novel method for the 3-D reconstruction of the rib cage, based only on two standard radiographs, is proposed in this paper. For each rib, two points are extrapolated from the reconstructed spine, and three points are reconstructed by stereo radiography. The reconstruction is then refined using a surface approximation. The method was evaluated using clinical data of 13 patients with scoliosis. A comparison was conducted between the reconstructions obtained with the proposed method and those obtained by using a previous reconstruction method based on two frontal radiographs. A first comparison criterion was the distances between the reconstructed ribs and the surface topography of the trunk, considered as the reference modality. The correlation between ribs axial rotation and back surface rotation was also evaluated. The proposed method successfully reconstructed the ribs of the 6th-12th thoracic levels. The evaluation results showed that the 3-D configuration of the new rib reconstructions is more consistent with the surface topography and provides more accurate measurements of ribs axial rotation.
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Wind energy has emerged as a major sustainable source of energy.The efficiency of wind power generation by wind mills has improved a lot during the last three decades.There is still further scope for maximising the conversion of wind energy into mechanical energy.In this context,the wind turbine rotor dynamics has great significance.The present work aims at a comprehensive study of the Horizontal Axis Wind Turbine (HAWT) aerodynamics by numerically solving the fluid dynamic equations with the help of a finite-volume Navier-Stokes CFD solver.As a more general goal,the study aims at providing the capabilities of modern numerical techniques for the complex fluid dynamic problems of HAWT.The main purpose is hence to maximize the physics of power extraction by wind turbines.This research demonstrates the potential of an incompressible Navier-Stokes CFD method for the aerodynamic power performance analysis of horizontal axis wind turbine.The National Renewable Energy Laboratory USA-NREL (Technical Report NREL/Cp-500-28589) had carried out an experimental work aimed at the real time performance prediction of horizontal axis wind turbine.In addition to a comparison between the results reported by NREL made and CFD simulations,comparisons are made for the local flow angle at several stations ahead of the wind turbine blades.The comparison has shown that fairly good predictions can be made for pressure distribution and torque.Subsequently, the wind-field effects on the blade aerodynamics,as well as the blade/tower interaction,were investigated.The selected case corresponded to a 12.5 m/s up-wind HAWT at zero degree of yaw angle and a rotational speed of 25 rpm.The results obtained suggest that the present can cope well with the flows encountered around wind turbines.The areodynamic performance of the turbine and the flow details near and off the turbine blades and tower can be analysed using theses results.The aerodynamic performance of airfoils differs from one another.The performance mainly depends on co-efficient of performnace,co-efficient of lift,co-efficient of drag, velocity of fluid and angle of attack.This study shows that the velocity is not constant for all angles of attack of different airfoils.The performance parameters are calculated analytically and are compared with the standardized performance tests.For different angles of ,the velocity stall is determined for the better performance of a system with respect to velocity.The research addresses the effect of surface roughness factor on the blade surface at various sections.The numerical results were found to be in agreement with the experimental data.A relative advantage of the theoretical aerofoil design method is that it allows many different concepts to be explored economically.Such efforts are generally impractical in wind tunnels because of time and money constraints.Thus, the need for a theoretical aerofoil design method is threefold:first for the design of aerofoil that fall outside the range of applicability of existing calalogs:second,for the design of aerofoil that more exactly match the requirements of the intended application:and third,for the economic exploration of many aerofoil concepts.From the results obtained for the different aerofoils,the velocity is not constant for all angles of attack.The results obtained for the aerofoil mainly depend on angle of attack and velocity.The vortex generator technique was meticulously studies with the formulation of the specification for the right angle shaped vortex generators-VG.The results were validated in accordance with the primary analysis phase.The results were found to be in good agreement with the power curve.The introduction of correct size VGs at appropriate locations over the blades of the selected HAWT was found to increase the power generation by about 4%
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GLOSARIO • Neuromarketing: El Neuromarketing consiste en la aplicación de las técnicas de investigación de las Neurociencias a la investigación de marketing tradicional. A través de técnicas de medición de la actividad cerebral (como el EGG o la fMRI), las “respuestas” de los entrevistados a distintos estímulos (por ejemplo, anuncios publicitarios) son leídas directamente de su actividad cerebral (Neuromarca) • Neurociencia: La neurociencia estudia la estructura y la función química, farmacología, y patología del sistema nervioso y de cómo los diferentes elementos del sistema nervioso interactúan y dan origen a la conducta (Neurologia y ove) • Mercadeo: Según la American Marketing Asociation (A.M.A.), el marketing es una forma de organizar un conjunto de acciones y procesos a la hora de crear un producto “para crear, comunicar y entregar valor a los clientes, y para manejar las relaciones” y su finalidad es beneficiar a la organización satisfaciendo a los clientes (Revista PYM) • Cerebro: Es la parte más evolucionada y grande del encéfalo. En el cerebro se dan la cognición, el pensamiento y las emociones; también la memoria y el lenguaje. Tiene dos hemisferios, cada uno con 4 lóbulos: frontal, temporal, parietal y occipital. La parte más externa es el cortex cerebral, que tiene unos repliegues que forman circunvoluciones y cisuras (Enciclopedia Salud) • Estrategia Empresarial: Es la que define las diferentes líneas de acción que debe asumir cada uno de los individuos que desempeñan las funciones dentro de la misma y permite a toda organización generar una ventaja competitiva en el mercado en el que desenvuelve sus actividades, generando mayores utilidades y permitiendo aprovechar cada una de las oportunidades dándole un valor agregado (Emagister) • Integración sensorial: Es un proceso Neurológico por el cual las sensaciones que provienen de nuestro entornoy de nuestro cuerpo, son organizadas e interpretadas para su uso (Enciclopedia Salud) • Top of Mind: Es el indicador que revela cuál es la marca que, cuando le preguntan por una categoría específica, se le viene a la mente en primer lugar al mayor porcentaje de personas (Gerente) • Valor Agregado: Valor agregado o valor añadido, en términos de marketing, es una característica o servicio extra que se le da a un producto o servicio, con el fin de darle un mayor valor comercial; generalmente se trata de una característica o servicio poco común, o poco usado por los competidores, y que le da al negocio o empresa cierta diferenciación (Crece Negocios)
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Aplicar posibles diferencias a pacientes con daños cerebral frontal y a pacientes con daño cerebral en regiones fuera de los lóbulos frontales. Busca diferencias entre daño frontal y daño parietal, añadiendo un tercer grupo con daño en otras zonas cerebrales. 299 pacientes entre varones y mujeres, con daño cerebral de los 14 a los 80 años de edad. De estos sujetos se descartaron 99 por no haberse completado el estudio de causa de: traslado a otro centro hospitalario; alta por mejoría y estabilización; no colaboración en la exploración con agresividad verbal y en algunos caso física; empeoramiento del cuadro clínico entre los más destacados. A cada paciente se le asignó a un grupo de sujetos con lesión en zonas frontales, y otros con lesión en zonas no frontales, ya sean parieto-occipitales o en otras regiones cerebrales. La elección de los sujetos fue de forma aleatoria, en función de su ingreso en el Hospital de León y sus posibilidades a la hora de realizar la evaluación neuropsicológica. Cuestionario de Salud General, Escala de Autoestima de Rosenberg, Batería Luria-DNA, test de vocabulario en imágenes, evaluación cognitiva y entrevistas. El cuestionario de Salud General para medir y evaluar el estado de salud psicológica del paciente; la escala de autoestima de Rosenberg par medir la autoestima. Para realizar la exploración neuropsicológica la batería Luria-DNA o Diagnóstico Neuropsicológico de Adultos mediante la que se exploran: el área visoespacial, el área lingüística, el área de memoria y el área de proceso intelectuales. El test de vocabulario en imágenes para medir la capacidad de vocabulario. Y finalmente para la evaluación cognitiva se sirven del test de inteligencia breve o K-BIT. 1) La lesión frontal produce un deterioro de las capacidades visoespaciales diferentes según el género. 2) No hay diferencias de capacidades lingüísticas por razón de género. 39 las mujeres son más propensas a padecer afasia que los hombres es caso de lesión de la parte frontal del cerebro.. 4) No se hayan diferencias ni de hemisferio ni de género en los subtest lingüísticos empleados. 5) Peores consecuencias de las lesiones frontales derechas para las mujeres, siendo más perniciosas para los varones las lesiones frontales izquierdas. 6) Entre las lesiones frontales no hay diferencias den autoestima, ni por género ni por hemisferio.7) Si hay diferencias en salud psicológica por razón de género, siendo las mujeres las que muestran peores puntuaciones en el cuestionario de salud general. En definitiva, podemos abordar las conclusiones finales en 12 objetivos: capacidades visoespaciales, capacidades lingüïsticas, capacidades de memoria, capacidad de atención, el nivel de severidad del Glasgow, el efecto principal de Locus, autoestima y salud psicológica en lesionados cerebrales, etiología y locus de la lesión, el análisis factorial, el análisis de cluster, la variable de edad y el nivel de educación.
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Monográfico con el título: "La investigación sobre el cerebro y la mejora de la educación".
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The life-cycle of shallow frontal waves and the impact of deformation strain on their development is investigated using the idealised version of the Met Office non-hydrostatic Unified Model which includes the same physics and dynamics as the operational forecast model. Frontal wave development occurs in two stages; first, a deformation strain is applied to a front and a positive potential vorticity (PV) strip forms, generated by latent heat release in the frontal updraft; second, as the deformation strain is reduced the PV strip breaks up into individual anomalies. The circulations associated with the PV anomalies cause shallow frontal waves to form. The structure of the simulated frontal waves is consistent with the conceptual model of a frontal cyclone. Deeper frontal waves are simulated if the stability of the atmosphere is reduced. Deformation strain rates of different strengths are applied to the PV strip to determine whether a deformation strain threshold exists above which frontal wave development is suppressed. An objective method of frontal wave activity is defined and frontal wave development was found to be suppressed by deformation strain rates $\ge 0.4\times10^{-5}\mbox{s}^{-1}$. This value compares well with observed deformation strain rate thresholds and the analytical solution for the minimum deformation strain rate needed to suppress barotropic frontal wave development. The deformation strain rate threshold is dependent on the strength of the PV strip with strong PV strips able to overcome stronger deformation strain rates (leading to frontal wave development) than weaker PV strips.
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The purpose of this paper is to show that, for a large class of band-dominated operators on $\ell^\infty(Z,U)$, with $U$ being a complex Banach space, the injectivity of all limit operators of $A$ already implies their invertibility and the uniform boundedness of their inverses. The latter property is known to be equivalent to the invertibility at infinity of $A$, which, on the other hand, is often equivalent to the Fredholmness of $A$. As a consequence, for operators $A$ in the Wiener algebra, we can characterize the essential spectrum of $A$ on $\ell^p(Z,U)$, regardless of $p\in[1,\infty]$, as the union of point spectra of its limit operators considered as acting on $\ell^p(Z,U)$.
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Case study simulations with idealized tracers have been used to determine the relationship between the dynamics and conceptual representations of different midlatitude frontal systems and the amount, distribution, and time scale of boundary layer ventilation by these systems. The key features of ventilation by a kata– and ana–cold frontal system are found to be quantitatively and also often qualitatively similar to the main ventilation pathways, which are the conveyor belts, cloud head, and other convection. The conveyor belts and cloud head occur within cloud, implying that they can be identified using satellite imagery. Differences in the transport by the two systems can be related to their conceptual representations and include a sensitive dependence on the diurnal cycle for the kata- but not the ana-cold frontal case.
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Reactive new bone on the endocranial surface of the skull in non-adults has recently received a lot of attention in the palaeopathological literature. These features appear as layers of new bone on the original cortical surface, expanding around meningeal vessels, as isolated plaques, 'hair-on-end' extensions of the diploe or, as 'capillary' impressions extending into the inner lamina of the cranium. These lesions are commonly found on the occipital bone, outlining the cruciate eminence, but have also been recorded on the parietal and frontal bones, and appear to follow the areas of venous drainage. Although recognized as resulting from haemorrhage or inflammation, their precise aetiology is still a matter of controversy. This paper outlines their possible causes and examines their nature and distribution in a group of non-adults from four archaeological sites in England. It is recommended that, when recording these lesions in the future, additional skeletal pathologies, the age of the child, and nature and distribution of the lesions also be taken into account. Copyright (C) 2004 John Wiley Sons, Ltd.