2D granular flows with the μ(I)\mu(I) rheology and side walls friction: a well balanced multilayer discretization

We present here numerical modelling of granular flows with the $\mu(I)$ rheology in confined channels. The contribution is twofold: (i) a model to approximate the Navier-Stokes equations with the $\mu(I)$ rheology through an asymptotic analysis. Under the hypothesis of a one-dimensional flow, this model takes into account side walls friction; (ii) a multilayer discretization following Fern\'andez-Nieto et al. (J. Fluid Mech., vol. 798, 2016, pp. 643-681). In this new numerical scheme, we propose an appropriate treatment of the rheological terms through a hydrostatic reconstruction which allows this scheme to be well-balanced and therefore to deal with dry areas. Based on academic tests, we first evaluate the influence of the width of the channel on the normal profiles of the downslope velocity thanks to the multilayer approach that is intrinsically able to describe changes from Bagnold to S-shaped (and vice versa) velocity profiles. We also check the well balance property of the proposed numerical scheme. We show that approximating side walls friction using single-layer models may lead to strong errors. Secondly, we compare the numerical results with experimental data on granular collapses. We show that the proposed scheme allows us to qualitatively reproduce the deposit in the case of a rigid bed (i. e. dry area) and that the error made by replacing the dry area by a small layer of material may be large if this layer is not thin enough. The proposed model is also able to reproduce the time evolution of the free surface and of the flow/no-flow interface. In addition, it reproduces the effect of erosion for granular flows over initially static material lying on the bed. This is possible when using a variable friction coefficient $\mu(I)$ but not with a constant friction coefficient

Deficiencia visual en el niño

La visión suministra una perspectiva global, simultánea y anticipadora del entorno. Un déficit severo de visión constituye un obstáculo para el adecuado desarrollo cognitivo y social del niño. La respuesta educativa a las necesidades prioritarias que la deficiencia visual genera, requiere una adecuada formación por parte de los profesionales: Para ello, es preciso que adquieran los conocimientos básicos relativos a la clasificación y el diagnóstico de la deficiencia visual, los aspectos esenciales del desarrollo y los fundamentos de la intervención educativa. El objetivo del presente trabajo es analizar las principales características de la deficiencia visual en los niños, y el impacto que dicha deficiencia tiene en el desarrollo y en el aprendizaje

Formal deduction of the Saint-Venant-Exner model including arbitrarily sloping sediment beds and associated energy

In this work we present a deduction of the Saint-Venant-Exner model through an asymptotic analysis of the Navier-Stokes equations. A multi-scale analysis is performed in order to take into account that the velocity of the sediment layer is smaller than the one of the fluid layer. This leads us to consider a shallow water type system for the fluid layer and a lubrication Reynolds equation for the sediment one. This deduction provides some improvements with respect to the classical Saint-Venant-Exner model: (i) the deduced model has an associated energy. Moreover, it allows us to explain why classical models do not have an associated energy and how to modify them in order to recover a model with this property. (ii) The model incorporates naturally a necessary modification that must be taken into account in order to be applied to arbitrarily sloping beds. Furthermore, we show that this modification is different of the ones considered classically, and that it coincides with a classical one only if the solution has a constant free surface. (iii) The deduced solid transport discharge naturally depends on the thickness of the moving sediment layer, what allows to ensure sediment mass conservation. Moreover, we include a simplified version of the model for the case of quasi-stationary regimes. Some of these simplified models correspond to the generalization of classical ones such as Meyer-Peter$\&$M\"uller and Ashida-Michiue models. Three numerical tests are presented to study the evolution of a dune for several definition of the repose angle, to see the influence of the proposed definition of the effective shear stress in comparison with the classical one, and by comparing with experimental data.Comment: 44 pages, sumbitted to Advances in Water Resources 17 july 201

Thermal 3D CFD Simulation with Active Transparent Façade in Buildings

In recent years active façades have acquired greater importance given their capacity to improve the energy efficiency of buildings. One such type is the so-called Active Transparent Façade (ATF). A 3D numerical model based on computational fluid dynamics (CFD) and the Finite Element Method (FEM) has been generated to simulate the thermal performance of buildings equipped with this type of façade. This model is introduced for general application and allows the design parameters to be adapted for this system. The case study of Le Corbusier’s proposal for the City of Refuge in Paris, the clearest example of previous use of an ATF is examined. In addition, a proposal is presented for the energy improvement of Le Corbusier’s original solution. In order to do so, the conditions for the supply of air into the ATF cavity and in the mechanical ventilation system are assessed to guarantee comfort conditions

Dificultades en la percatación rápida de incongruencias en el trastorno de aprendizaje procedimental: posible disfunción de la coherencia central

Procedural learning disorder, or non-verbal learning disorder, affects the automation of perceptual motor and cognitive skills and routines. AIM: To further our knowledge of the neurocognitive dysfunction in this disorder and, more specifically, to analyse the difficulties experienced when going from recognition of the constituting elements of something to an understanding of the whole. DEVELOPMENT: Contrasting simultaneous visual information and the swift recognition of contradictions are especially difficult abilities for children with procedural learning disorder. CONCLUSIONS: These difficulties may reflect a central coherence dysfunction and can partly account for the deficient ability to adapt their social behaviour displayed by these childre

Thermal 3D CFD Simulation with Active Transparent Façade in Buildings

In recent years active façades have acquired greater importance given their capacity to improve the energy efficiency of buildings. One such type is the so-called Active Transparent Façade (ATF). A 3D numerical model based on computational fluid dynamics (CFD) and the Finite Element Method (FEM) has been generated to simulate the thermal performance of buildings equipped with this type of façade. This model is introduced for general application and allows the design parameters to be adapted for this system. The case study of Le Corbusier’s proposal for the City of Refuge in Paris, the clearest example of previous use of an ATF is examined. In addition, a proposal is presented for the energy improvement of Le Corbusier’s original solution. In order to do so, the conditions for the supply of air into the ATF cavity and in the mechanical ventilation system are assessed to guarantee comfort conditions

Detección y estudios específicos en el trastorno de aprendizaje procesal

The main disabilities in non-verbal learning disorder (NLD) are: the acquisition and automating of motor and cognitive processes, visual spatial integration, motor coordination, executive functions, difficulty in comprehension of the context, and social skills. AIMS. To review the research to date on NLD, and to discuss whether the term 'procedural learning disorder' (PLD) would be more suitable to refer to NLD. DEVELOPMENT: A considerable amount of research suggests a neurological correlate of PLD with dysfunctions in the 'posterior' attention system, or the right hemisphere, or the cerebellum. Even if it is said to be difficult the delimitation between NLD and other disorders or syndromes like Asperger syndrome, certain characteristics contribute to differential diagnosis. Intervention strategies for the PLD must lead to the development of motor automatisms and problem solving strategies, including social skills. CONCLUSIONS: The basic dysfunction in NLD affects to implicit learning of routines, automating of motor skills and cognitive strategies that spare conscious resources in daily behaviours. These limitations are partly due to a dysfunction in non-declarative procedural memory. Various dimensions of language are also involved: context comprehension, processing of the spatial and emotional indicators of verbal language, language inferences, prosody, organization of the inner speech, use of language and non-verbal communication; this is why the diagnostic label 'PLD' would be more appropriate, avoiding the euphemistic adjective 'non-verbal'

El sistema ejecutivo y las lesiones frontales en el niño

Frontal lobe syndrome in adulthood is characterised by executive function deficits leading to altered behavioural control with difficulties in social interactions and in maintaining stable jobs and interpersonal relationships. Generalisation of this concept to children with early frontal lobe damage is not straightforward. There are complex interactions between the effects of the lesion itself and the effects in other interconnected regions, timing of lesion, how long it was since the lesion occurred to the time of evaluation, and how old the child is at examination. These facts lead to consider that there might be a number of 'frontal syndromes' in childhood rather than a unique one. We report 9 cases of children with early frontal lobe lesions who were followed up for an average of 10 years. CONCLUSION: A variety of different outcomes suggests that prognosis for these patients might be better that previously reported

El síndrome de Rett como patología de la hodogénesis

En los últimos cinco años se viene adoptando la concepción del síndrome de Rett como un peculiar trastorno del neurodesarrollo posmigracional que impide la correcta formación de las interconexiones dendríticas en estructuras corticales y subcorticales. Se comenta aquí la particular patocronía de las formas clásicas y los datos más recientes de investigación neurobiológica y genética que sugieren posibles explicaciones, a confirmar en el futuro, acerca de la naturaleza y el origen de este síndrome

Fenomenología depresiva al inicio de enfermedades neuropediátricas

Introducción. La depresión, en sus diversas formas, afecta al 8-10% de niños y adolescentes y en la mayor parte de casos su origen es primario, siguiendo el modelo genético multifactorial. Pero hay una proporción de pacientes, no bien cuantificada todavía, en la que la depresión acompaña precozmente una enfermedad neurológica o marca un punto de inflexión en el curso de ésta. El objetivo es revisar la bibliografía al respecto. Desarrollo. Se observa fenomenología depresiva, con una frecuencia significativamente mayor que por azar, en niños y adolescentes afectos de epilepsia, trastornos del sueño, cefaleas primarias crónicas recurrentes, enfermedades neurome- tabólicas y tumores intracraneales. En varias de estas patologías neuropediátricas se hipotetizan puntos de coincidencia fisiopatológica con la depresión a través de un déficit de disponibilidad cerebral de serotonina y noradrenalina. No se considera aquí la depresión disadaptativa a una neurodiscapacidad crónica. Conclusiones. En niños y adolescentes, los trastornos del ánimo sintomáticos de enfermedad neurológica deben sospechar- se en ausencia de antecedentes familiares o de experiencias vitales que los expliquen. La búsqueda sistemática de anoma- lías neurológicas y los exámenes complementarios permitirían en estos casos abordar precozmente el tratamiento de la enfermedad cerebral causante del cuadro depresivo. A su vez, como ocurre en casos de epilepsia, cefaleas o trastorno del sueño, la terapia farmacológica y psicológica del cuadro depresivo contribuye a mejorar la calidad de vida de los afectados