395 research outputs found
Urban transport and mobility, towards a sustainable and competitive urban dynamic
El presente artículo pretende aportar algunas ideas sobre este tema en función de la interdependencia que existe entre los usos del suelo y el transporte, considerando al primero como sinónimo de actividades urbanas y al segundo como el medio de intercambio físico entre ellas. El discurso propone un análisis de la dinámica urbana con base en tres dimensiones: la formal, la funcional y la moral, procurando asociarlas a los paradigmas de la sustentabilidad y la competitividad urbanas, tratando de relacionarlas con los procesos de globalización para satisfacer las necesidades de movilidad en la ciudad posmoderna. Finalmente, se mencionan las características que los servicios de transporte público urbano de pasajeros deberían observar para contribuir a los objetivos funcionales y ambientales en los procesos de administración de la ciudad.A lo largo de la historia el hombre ha buscado formas diversas de transporte para realizar sus desplazamientos de manera más eficiente y confortable; en tal sentido, la evolución de los medios de transporte y la infraestructura física sobre la que discurren juegan un papel fundamental en la eficiencia y la eficacia de la movilidad de la población y sus bienes. El transporte urbano es un componente de la dimensión funcional de la ciudad y, junto con los usos del suelo, condiciona la manera en que se llevan cabo las actividades urbanas. En su conjunto, este fenómeno es conocido como “dinámica urbana”
Identificación y descripción de las explicaciones de los alumnos mediante una prueba de opción múltiple obtenida a partir de los resultrados de entrevistas
On the use of stabilization techniques in the Cartesian grid finite element method framework for iterative solvers
"This is the peer reviewed version of the following article: Navarro-Jiménez, José Manuel, Enrique Nadal, Manuel Tur, José Martínez-Casas, and Juan José Ródenas. 2020. "On the Use of Stabilization Techniques in the Cartesian Grid Finite Element Method Framework for Iterative Solvers." International Journal for Numerical Methods in Engineering 121 (13). Wiley: 3004-20. doi:10.1002/nme.6344, which has been published in final form at https://doi.org/10.1002/nme.6344. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving."[EN] Fictitious domain methods, like the Cartesian grid finite element method (cgFEM), are based on the use of unfitted meshes that must be intersected. This may yield to ill-conditioned systems of equations since the stiffness associated with a node could be small, thus poorly contributing to the energy of the problem. This issue complicates the use of iterative solvers for large problems. In this work, we present a new stabilization technique that, in the case of cgFEM, preserves the Cartesian structure of the mesh. The formulation consists in penalizing the free movement of those nodes by a smooth extension of the solution from the interior of the domain, through a postprocess of the solution via a displacement recovery technique. The numerical results show an improvement of the condition number and a decrease in the number of iterations of the iterative solver while preserving the problem accuracy.The authors wish to thank the Spanish "Ministerio de Economía y Competitividad," the "Generalitat Valenciana," and the "Universitat Politècnica de València" for their financial support received through the projects DPI2017-89816-R, Prometeo 2016/007 and the FPI2015 program, respectively.Navarro-Jiménez, J.; Nadal, E.; Tur Valiente, M.; Martínez Casas, J.; Ródenas, JJ. (2020). On the use of stabilization techniques in the Cartesian grid finite element method framework for iterative solvers. International Journal for Numerical Methods in Engineering. 121(13):3004-3020. https://doi.org/10.1002/nme.6344S3004302012113Burman, E., & Hansbo, P. (2010). Fictitious domain finite element methods using cut elements: I. A stabilized Lagrange multiplier method. Computer Methods in Applied Mechanics and Engineering, 199(41-44), 2680-2686. doi:10.1016/j.cma.2010.05.011Ruiz-Gironés, E., & Sarrate, J. (2010). Generation of structured hexahedral meshes in volumes with holes. Finite Elements in Analysis and Design, 46(10), 792-804. doi:10.1016/j.finel.2010.04.005Geuzaine, C., & Remacle, J.-F. (2009). Gmsh: A 3-D finite element mesh generator with built-in pre- and post-processing facilities. International Journal for Numerical Methods in Engineering, 79(11), 1309-1331. doi:10.1002/nme.2579Parvizian, J., Düster, A., & Rank, E. (2007). Finite cell method. Computational Mechanics, 41(1), 121-133. doi:10.1007/s00466-007-0173-yDüster, A., Parvizian, J., Yang, Z., & Rank, E. (2008). The finite cell method for three-dimensional problems of solid mechanics. Computer Methods in Applied Mechanics and Engineering, 197(45-48), 3768-3782. doi:10.1016/j.cma.2008.02.036Nadal, E., Ródenas, J. J., Albelda, J., Tur, M., Tarancón, J. E., & Fuenmayor, F. J. (2013). Efficient Finite Element Methodology Based on Cartesian Grids: Application to Structural Shape Optimization. Abstract and Applied Analysis, 2013, 1-19. doi:10.1155/2013/953786Nadal, E., Ródenas, J. J., Sánchez-Orgaz, E. M., López-Real, S., & Martí-Pellicer, J. (2014). Sobre la utilización de códigos de elementos finitos basados en mallados cartesianos en optimización estructural. Revista Internacional de Métodos Numéricos para Cálculo y Diseño en Ingeniería, 30(3), 155-165. doi:10.1016/j.rimni.2013.04.009Giovannelli, L., Ródenas, J. J., Navarro-Jiménez, J. M., & Tur, M. (2017). Direct medical image-based Finite Element modelling for patient-specific simulation of future implants. Finite Elements in Analysis and Design, 136, 37-57. doi:10.1016/j.finel.2017.07.010Schillinger, D., & Ruess, M. (2014). The Finite Cell Method: A Review in the Context of Higher-Order Structural Analysis of CAD and Image-Based Geometric Models. Archives of Computational Methods in Engineering, 22(3), 391-455. doi:10.1007/s11831-014-9115-yBurman, E., Claus, S., Hansbo, P., Larson, M. G., & Massing, A. (2014). CutFEM: Discretizing geometry and partial differential equations. International Journal for Numerical Methods in Engineering, 104(7), 472-501. doi:10.1002/nme.4823Tur, M., Albelda, J., Marco, O., & Ródenas, J. J. (2015). Stabilized method of imposing Dirichlet boundary conditions using a recovered stress field. Computer Methods in Applied Mechanics and Engineering, 296, 352-375. doi:10.1016/j.cma.2015.08.001Tur, M., Albelda, J., Nadal, E., & Ródenas, J. J. (2014). Imposing Dirichlet boundary conditions in hierarchical Cartesian meshes by means of stabilized Lagrange multipliers. International Journal for Numerical Methods in Engineering, 98(6), 399-417. doi:10.1002/nme.4629De Prenter, F., Verhoosel, C. V., van Zwieten, G. J., & van Brummelen, E. H. (2017). Condition number analysis and preconditioning of the finite cell method. Computer Methods in Applied Mechanics and Engineering, 316, 297-327. doi:10.1016/j.cma.2016.07.006Berger-Vergiat, L., Waisman, H., Hiriyur, B., Tuminaro, R., & Keyes, D. (2011). Inexact Schwarz-algebraic multigrid preconditioners for crack problems modeled by extended finite element methods. International Journal for Numerical Methods in Engineering, 90(3), 311-328. doi:10.1002/nme.3318Menk, A., & Bordas, S. P. A. (2010). A robust preconditioning technique for the extended finite element method. 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N., de Prenter, F., Elhaddad, M., D’Angella, D., Verhoosel, C. V., Kollmannsberger, S., … Rank, E. (2019). Robust and parallel scalable iterative solutions for large-scale finite cell analyses. Finite Elements in Analysis and Design, 163, 14-30. doi:10.1016/j.finel.2019.01.009Béchet, É., Moës, N., & Wohlmuth, B. (2008). A stable Lagrange multiplier space for stiff interface conditions within the extended finite element method. International Journal for Numerical Methods in Engineering, 78(8), 931-954. doi:10.1002/nme.2515Hautefeuille, M., Annavarapu, C., & Dolbow, J. E. (2011). Robust imposition of Dirichlet boundary conditions on embedded surfaces. International Journal for Numerical Methods in Engineering, 90(1), 40-64. doi:10.1002/nme.3306Hansbo, P., Lovadina, C., Perugia, I., & Sangalli, G. (2005). A Lagrange multiplier method for the finite element solution of elliptic interface problems using non-matching meshes. 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Colour morph does not predict brood size in the Booted Eagle.
Mechanisms regulating colour polymorphism remain largely unknown and detailed investigation is required to explore the biological consequences on population dynamics. This paper presents the first study of the possible connection between colour polymorphism and productivity in a Booted Eagle (Aquila pennata) population breeding in southeastern Spain. To that end we used 19 years of data of non-marked individuals. A total of 738 pale (91.6%) and 68 dark (8.4%) adult Booted Eagles were observed in our study area, including 57 territories. Our results suggest that colour morph of both sexes remained stable in the population over the study period. Although we found a higher number of offspring produced by parents exhibiting the dark morph than those of the pale morph, statistical differences were not significant. Hence, our models showed that colour polymorphism was not a good predictor of Booted Eagles'productivity, although further research by capture-recapture analysis would be needed to explore the influence of colour variation on fitness components at individual level and its consequences at population level of long-lived species
PLK1 regulates centrosome migration and spindle dynamics in male mouse meiosis
Cell division requires the regulation of karyokinesis and cytokinesis, which includes an essential role of the achromatic spindle. Although the functions of centrosomes are well characterised in somatic cells, their role during vertebrate spermatogenesis remains elusive. We have studied the dynamics of the meiotic centrosomes in male mouse during both meiotic divisions. Results show that meiotic centrosomes duplicate twice: first duplication occurs in the leptotene/zygotene transition, while the second occurs in interkinesis. The maturation of duplicated centrosomes during the early stages of prophase I and II are followed by their separation and migration to opposite poles to form bipolar spindles I and II. The study of the genetic mouse model Plk1(Δ/Δ) indicates a central role of Polo-like kinase 1 in pericentriolar matrix assembly, in centrosome maturation and migration, and in the formation of the bipolar spindles during spermatogenesis. In addition, in vitro inhibition of Polo-like kinase 1 and Aurora A in organotypic cultures of seminiferous tubules points out to a prominent role of both kinases in the regulation of the formation of meiotic bipolar spindlesThis work was supported by funding from Ministerio de Economía, Industria y Competitividad, Gobierno de España (MINECO) (Spain) [grant number BFU2014-53681-P and MEIONET (BFU2015-71786-REDT) to J. A. S. and grant number RTI2018-095582-B-I00 to M. M.]
El quiste óseo aneurismático en niños y adolescentes
Desde el año 1981 hasta el año 1996 hemos tratado en nuestro servicio un total de 12 pacientes con diagnóstico de Quiste Óseo Aneurismático (QOA). Esta entidad clínico-patológica continúa hoy teniendo un origen incierto que en la mayoría de las ocasiones no puede reconocerse. Los tratamientos empleados fueron: legrado e injerto óseo en siete casos, resección en bloque en tres casos, y en 2 casos tratamiento expectante.
Los resultados del tratamiento quirúrgico fueron satisfactorios en el 75% de los casos, encontrando un 25% de recidivas, que ocurrieron en los pacientes más jóvenes con quistes más agresivos. El tiempo medio de seguimiento fue de 4 años (mínimo 1 - máximo 8). Realizamos en el trabajo, además, una comparación con otros métodos de tratamiento publicados como son la crioterapia intratumoral y la embolizacón arterial selectiva, los cuales encontramos de utilidad relativa ya que requieren una alta especialización y una selección precisa de los casos. También la radioterapia que tiene una utilidad restringida a aquellos casos de inaccesibilidad operatoria.From 1981 to 1996 twelve patients were treated in our orthopaedic department with the diagnosis of Aneurismal Bone Cyst (ABC). This pathologic and clinical entity has an unknown etiology that in the majority of cases it can¿t be elucidated. The threatment was: curettage and bone graft in seven cases; in bloc excision in three cases and expectant in two. Surgical treatment results were satisfactory in 75% of cases, with 25% of local recurrences that took place in younger patients with more aggressive cysts. Mean follow-up was four years (range: 1-8). In this study we make a comparison with other methods of treatment reported like intratumoral criotherapy and selective arterial embolization. We find these methods of relative utility due to their high level of orthopaedist specialization and precise selection of cases. The radiotherapy has restricted application to cases of unresectable tumours
Trew@sig: spatial workflow. Workflow y SIG para la I-Administación
Trew@SIG nace para cubrir la necesidad de gestión de información espacial asociada a los flujos de trabajo en la
tramitación de expedientes de la administración electrónica. Es un completo framework de desarrollo que
proporciona la total integración de los Sistemas de Información Geográfica con datos de gestión, como un módulo
complementario "al sistema de tramitación". Esto es, un entorno de desarrollo multifuncional, aplicable a diferentes
ámbitos de la gestión pública, como el urbanismo, recursos hídricos, inventarios georreferenciados, participación
pública, etc.
Trew@SIG se fundamenta en dos conceptos básicos. Por un lado, el “Momento de Tramitación”, definido por el
estado en el que se encuentra el proceso de trabajo y las necesidades de información espacial y herramientas, que
apoyarán la toma de decisiones para la continuación del flujo. Por otro, el “GeoPerfil”, como conjunto de capas y
herramientas de gestión de la información espacial ligados al momento de tramitación y a las necesidades del
usuario.
Estas capacidades se han desarrollado en entornos diferentes: web, escritorio y móvil, todos ellos según normas
OGC y usando componentes desarrollados en software libre, entre los que se encuentran:
• Núcleo de integración con el workflow, que ofrece las funcionalidades adecuadas para la integración del
sistema con el momento de tramitación.
• Núcleo SIG., aporta todas las funcionalidades para la gestión de la información espacial, basado en
estándares OGC: WMS, WFS, WFS-G, WPS.
• Trew@SIG cliente web, aporta las funcionalidades de visualización de capas y herramientas de gestión
mediante un framework de desarrollo basado en tecnologías OpenSource.
• Aplicación de movilidad basada en Enebro Framework, que incorpora las funcionalidades necesarias para
las operaciones de campo.
• Aplicación de escritorio basada en gvSIG y empleada para aprovechar toda la potencia de esta herramienta
de escritorio.
Trew@SIG puede ser usado por cualquier entidad pública o privada en procesos trabajo, mejorando la gestión de
datos y ofreciendo todos los instrumentos requeridos en la toma de decisiones que requieran consultar, capturar,
modificar o analizar elementos territoriales.
El resultado es un entorno de desarrollo que permite modelar procesos de gestión con dimensión espacial, de
fácil implantación, implementado con tecnologías de fuentes abiertas y bajo estándares OGC. Ofrece a las distintas
organizaciones y usuarios la posibilidad de integrar en sus procesos de trabajo datos y funcionalidades espaciales,
hasta ahora, tratadas con herramientas y en entornos diferentes.Trew@SIG is born to cover the need of spatial data management in workflow-processing. Trew@SIG is a complete
framework to develop professional workflow solutions providing total GIS-Data integration,as an add-on module to
the pure-workflow-system. It's a multipurpose framework, being used in different workflow enviroments, as urbanism,
hydrological processes, multipurposal inventaries, urban tasks, contingency management, etc.
Trew@SIG is based on two basic concepts “Workflow momentum” and “GeoProfile”. Workflow momentum is an
unique combination of workflow status with specific needs of spatial information and tools,in order to decide which
way the workflow will go on. GeoProfile is defined as a set of layers and tools to manage spatial information.
This way, Trew@SIG deals with workflow and spatial data associating a geoprofile to a certain workflow
momentum, providing the user with all spatial information and capabilities needed to go ahead with the next step of
the workflow process.
These capabilities are offered in different enviroments: web, desktop and mobile, all of them according to OGC
standards and using open source components, which are detailed as follows:
•Workflow integration core, which offers full integration with workflow processes. It has been integrated with Trew@
workflow system, based on WFMC (WorkFlowManagementCoalition) standards, implementing XPDL and WSDL
standards.
•GIS core,this module contains all the GIS functionallities based on OGC standards: WMS,WFS,WFS-G,WPS.
•Trew@SIG webclient,open for different client mapping frameworks.Full configuration of a geoprofile (layers&tools)
implemented for OpenLayers and Mapfish.
•Desktop application,based on gvSIG, provides advanced users full and highest performance managing spatial data.
•Fieldwork application,based on Enebro, gives full capabilities for fieldwork operations,GPS-capturing,editing,etc.
Trew@SIG can be used for any public or private entity for their own workflow processes,improving the
management of data,offering all the tools required to make a decision in a process.
To sum up,Trew@SIG makes workflow processing much easier,faster and simpler to deploy,joining the effort of
leading opensource projects in a framework and offering the final users GIS data and functionalities completely
integrated in workflow processing
Fracturas femorales en pacientes portadores de artroplastia de cadera
Se han revisado 25 pacientes con fractura femoral portadores de artroplatia de cadera. Las fracturas se clasifican según los tipos de Johansson. Se encontraron 9 tipo I, 9 tipo II y 7 tipo III. El tratamiento fue en 4 ocasiones conservador y en 21 quirúrgico: 2 osteosíntesis con tornillos de compresión, 9 recambios de vástago y 9 osteosíntesis con placa. Se valora el resultado del tratamiento de la fractura. Consolidaron todas salvo una tras el tratamiento inicial. El resultado de la artroplastia fue valorado según la Escala de Merle D'Aubigne siendo bueno en un 68% de los casos. Las complicaciones fueron 2 consolidaciones en varo, una infección superficial y una infección profunda. Se evalúan los diferentes tratamientos realizados y se expone nuestra actitud actual ante estas fracturas.The present study includes 25 patients with hip replacement who presented an ipsilateral fracture of the femur. According to Johansson's grading system, there were 9 types I fractures, 9 types II and 7 types III. Surgical treatment was indicated in 21 cases, and conservative treatment in 4. Of the 21 patients operated on 9, required stem replacement, 9 internal fixations with plate and screws, and inter-fragmentary compression screws in 2 cases. Outcome assessment showed that, except one case, all fractures healded after treatment. The results of the arthroplasty were good in 68% of cases according to the Merle D'Aubigne scale. Complications included 2 various deformities, one superficial infection and one deep infection
Evidence of non‑random mating in a colour polymorphic raptor, the Booted Eagle
©2020. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/
This document is the Accepted version of a Published Work that appeared in final form in Journal of Ornithology. To access the final edited and published work see https://doi.org/10.1007/s10336-020-01763-ySexual selection and non-random mating are considered, among others, determinant mechanisms for the maintenance of
genetic colour polymorphism in some bird species. We analyse the mechanisms, which, in parallel with Mendelian inherit ance, may be acting in the maintenance and evolution of the morph ratio in a two-morph raptor species, using observational
data of successful breeding individuals and their ofspring from long-term studies conducted in three Spanish populations.
Our results showed that the dark ofspring produced in breeding events involving mixed-morph adult pairs far exceeds the
expected value under the Hardy–Weinberg equilibrium, especially in the case of pairs formed by a light male and a dark
female. In addition, the low number of dark eaglets born from pairs formed by light individuals (indistinctly homozygous or
heterozygous) indicates that the number of breeding events of heterozygous (both the male and female) light morph pairs,
was much lower than expected. As the plausible existence of a transmission ratio distortion phenomenon in heterozygous
light morph males does not, alone, explain the disproportionate number of dark eaglets observed, our results suggest that
one or two selective mating phenomena may be occurring in this polymorphic system. The frst one could be a disassortative
mating process whereby heterozygous light males preferentially mate with dark females, based on the imprint of the colour
morph of their mother. The second phenomenon would only afect light morph individuals, which would preferentially mate
with heterozygous individuals of the opposite sex, selected according to secondary sexual characteristics or behavioural
traits that are unknown at the momen
Estudio científico de los tubos sonoros de metal del órgano Francisco Pérez de Valladolid (S.XVIII). Alcalá de los Gazules (Cádiz)
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