50 research outputs found

    Transient activation in a network of coupled map neurons

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    The focus of this Letter is on the activity of a network of neurons pairwise coupled by inhibitory connections. Each neuron is represented by a two-dimensional map capable, when isolated, of a rich variety of complex dynamical regimes. It is shown that the network exhibits a stimulus-dependent sequential activation and inactivation of subgroups of neurons. This complex behavior is rather similar to some spatiotemporal features observed in the first stages of the olfaction process in some insects and suggests the possibility of large scale simulation of these processes by using reasonable computational capabilities.Dirección General de Investigación Científica y Técnica BFM2002-0382

    Noise-induced forced synchronization of global variables in coupled bistable systems

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    We analyze the noise-induced synchronization between a collective variable characterizing a complex system with a finite number of interacting bistable units and time-periodic driving forces. A random phase process associated to the collective stochastic variable is defined. Its average phase frequency and average phase diffusion are used to characterize the phenomenon. Our analysis is based on numerical solutions of the corresponding set of Langevin equations.Ministerio de Educación y Ciencia FIS2005-0288

    Dynamics of single and multiple Zener transitions

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    The probability of remaning in a given state is evaluated for a two-level system that can cross repeatedly and periodically as a function of a control parameter. The possibility of multiple Zener transitions between the surfaces introduces the issue of the appropriate initial conditions for each successive transition. We devise a simple model, which is readily analyzed numerically, to evaluate the consequences of an initially nondiaganol density matrix on the subsequent evolution through the crossing region. The initial state strongly affects the outcome of the transition. Thus successive transitions are, in general, not independent of each other. Consequently, we find that the probability oscillates in time. This contrasts with the result of convergence at long times to a constant state occupation which would be predicted based solely on probabilities of single transitions. We also analyze the role that inelastic transitions play in modifying the nondissipative multiple-Zener-transition model. This model finds application to small tunnel junctions, where the control parameter is a current and the output is a voltage. Here, we show that the average dc voltage is nonzero when inelastic transitions are included, in contrast to the zero average voltage obtained in the absence of inelastic transitions, or when their rate is very large.Dirección General de Investigación Científica y Técnica PS89-0123OTAN CRG 89046

    Building and surroundings: thermal coupling

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    Energy building performance can be different according to outdoor conditions or urban environment, at the same time that this last assess, buildings are also affected by the building envelope, as obvious consequence of the thermal and Aeraulic coupling existing between the indoor and outdoor conditions in buildings. Thus, in this coupling is fundamental to typify the transmission phenomenon through the building envelope. Doing this, it is possible to estimate transmission heating losses and gains and also the superficial temperatures of the envelope. In order to assess the transient behaviour of the building envelope it is necessary to develop a predictive model, precise enough, to be integrated in a simulating tool. Detailed and multidimensional models, based in numerical methods, like Finite Element Method (FEM), has a high precision, but its complexity imply resources consumption and computational time, too high to be integrated in these kind of tools. On the contrary, simplified methods are good enough because they are simple and fast, with an acceptable precision in almost all the situations. The present work is focused: (a) Firstly, to develop a simplified RC-network model. The aim of the model is to characterize and to implement with precision the behaviour of a wall in a simulating software tool based on urban environment, (b) secondly, to express in form of equivalences, the different indoor and outdoor excitations that can exist in the building envelope, and (c) finally, to calibrate the simplified model through its characteristic parameters. For a homogeneous wall and two types of excitations, it has been obtained the characteristic parameters of the model that represent the better adjustment to the real wall. In a first step, it has been obtained the results of the proposal model and a reference model based on FEM, in terms of wall external surface heat flow. Results of both models have been compared, and the resultant characteristic parameters of the model have been obtained through an optimisation method. Results for the wall and for the excitations under analysis show: (1) Characteristic longitude ec, or capacitive node position, it is determined according to a certain value of Fo equal to 2 for both excitations, this value remains constant in time, (2) useful wall thickness, on the contrary, vary as time function, according to a logarithmic law for both excitations, although this function is different depending on the considered excitation, (3) using a constant excitation, coefficients from the previous logarithmic function depends on the range of the excitation, while these are practically independent of the lineal excitation gradient

    Menu Navigation in Mobile Devices Using the Accelerometer

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    In this article an application for mobile devices is presented. This application uses the accelerometer integrated into the own device to detect certain user movements and use them to navigate through the menus. The application is destined to those users with visual incapacity who need an alternative mechanism for the selection of the different options in the menus

    From the sierra to the lowlands: new data on the settlement of the Barbanza Peninsula from Prehistoric to Medieval times

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    Procédese á revisión dos traballos de prospección previa na serra do Barbanza e ampliados aos montes de Macenda e Bealo na procura de asentamentos gandeiros/pastorís, no curso deses traballos localizáronse ademáis un interesante xacemento de cronoloxía calcolítca e un castro inédito. Asemade, dáse conta dos resultados das intervencións en dous xacementos, un de carácter gandeiro que presenta un palimpsesto estrutural e cronolóxico (Río Barbanza), e outro relacionado con sistemas de control territorial (Outeiro da Torre).We review the survey works carried through in the district of Barbanza, now extended to the parishes of Macenda and Bealo in search of livestock / pastoral settlements. In the course of these explorations a Copper Age site was discovered and, nearby, a previously unknown hillfort. An account is given of the results of the digging in two sites; one related to husbandry tasks, that presents a structural and chronological palimpsest (Rio Barbanza); and another more, related to territorial control systems (Outeiro da Torre)

    Intraoperative oxygen tension and redox homeostasis in Pseudomyxoma peritonei: A short case series

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    IntroductionPseudomyxoma peritonei (PMP) is a rare malignant disease characterized by a massive multifocal accumulation of mucin within the peritoneal cavity. The current treatment option is based on complete cytoreductive surgery combined with hyperthermic intraperitoneal chemotherapy. However, the recurrence is frequent with subsequent progression and death. To date, most of the studies published in PMP are related to histological and genomic analyses. Thus, the need for further studies unveiling the underlying PMP molecular mechanisms is urgent. In this regard, hypoxia and oxidative stress have been extensively related to tumoral pathologies, although their contribution to PMP has not been elucidated.MethodsIn this manuscript, we have evaluated, for the first time, the intratumoral real-time oxygen microtension (pO2mt) in the tumor (soft and hard mucin) and surrounding healthy tissue from five PMP patients during surgery. In addition, we measured hypoxia (Hypoxia Inducible Factor-1a; HIF-1α) and oxidative stress (catalase; CAT) markers in soft and hard mucin from the same five PMP patient samples and in five control samples.ResultsThe results showed low intratumoral oxygen levels, which were associated with increased HIF-1α protein levels, suggesting the presence of a hypoxic environment in these tumors. We also found a significant reduction in CAT activity levels in soft and hard mucin compared with healthy tissue samples.DiscussionIn conclusion, our study provides the first evidence of low intratumoral oxygen levels in PMP patients associated with hypoxia and oxidative stress markers. However, further investigation is required to understand the potential role of oxidative stress in PMP in order to find new therapeutic strategies

    Reseñas de libros

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    Carrasca Hortal, José y Millán Gómez, Antonio. La Estructura Gótica Catalana. Sobre los conceptos de media y espacio. El problema de la forma en la cubierta (Por Antonio Millán) pp. 4.-- Verd Herrero, Antonio. Dibujo del natural. Manual de texto docente universitario (Por Antonio Verd) pp.5-6.-- Caninva, Luigi. L'Architettura romana (Por Carlos de San Antonio Gómez) pp.6-7.-- Villalobos Alonso, Daniel. La mirada de Fisac (Por Alberto Grijalba Bengoetxea)pp.8.-- Jiménez Martín, Alfonso et al. La catedral gótica de Sevilla. Fundación y fábrica de la obra nueva (Por Enrique Rabasa Díaz) pp.8-9.-- García-Gutiérrez Mosteiro, Javier. Narciso Pascual y Colomer (1808-1870). Arquitecto del Madrid isabelino (Por Enrique Rabasa Díaz) pp.9-10.-- Valladolid. Bellido Blanco, Santiago. Cuaderno de apuntes (Por Fernando Lmares García) pp.10-11.-- Lopez-Peláez, José Manuel. Maestros cercanos de un arquitecto (Por Javier García-Gutiérrez Masteiro) pp.12.-- Garcia Bueno, Antonio. Dibujando la Alhambra (Por Joaquín Casado de Amezúa Vázquez) pp.13-14.-- Chías Navarro, Pilar y Abad Balboa, Tomás. Eduardo Torroja. Obras y proyectos (Por Jorge Llopis Verdú) pp.14-15.-- Gómez i Serrano, Josep y Font, Juan. La forma de la Villa de Madrid. Soporte gráfico para la información histórica de la ciudad (Por Jorge Llopis Verdú) pp.15-16.-- Nagore, Fernando. Geometría métrica y descriptiva para arquitectos (Por José Antonio Ruiz de le Rosa) pp.16-17.-- Rabasa Diaz, Enrique y el Centro de los Oficios de LeónGuía práctica de la estereotomía de la piedra (Por José CalvoLópez) pp.18-19.-- Hernández Iviartinez, Ascensión. La clonación arquitectónica (Por José Joaquín Parra 8añón) pp.20-21.-- Gentil Baldrich, José María y Yanguas Álvarez de Toledo, Ana. Fernando Barquín y Barón Joaquín Barquín y Barón Imágenes de su archivo en los fondos FIDAS (Por José Manuel Pala) pp.21-22.-- Escoda Pastor, Carmen. El magnetismo del lugar en la arquitectura pp.23.-- Herrero Vázquez, Eduardo Alejandro. Compases de mano, compases de ojo: la Geometrización de la Realidad según Laussedat (POr Adrien Javary) pp.24-25.-- Castaño Perea, Enrique. Arquitectura y música: Policoralidad en la Capilla Real del Alcázar de Madrid pp.25-26.-- Piquer Cases, Juan Carlos. Los modelos digitales en la arquitectura, desarrollo del proyecto e investigación patrimonial. Palacio Real de Valencia (1239-1810): análisis y reconstrucción virtual sobre la planta de Vicente Gascó de 1761 (Por Juan Carlos Piquer Cases) pp.26-28.-- Pérez Naya, Antonia. Arquitectura del silencio y la memoria. Análisis de los cementerios de la Costa da Morte gallega (Por JAfT) pp. 28-29.-- Falcón Meraz, José Manuel. La expresión de una línea museística singular (Por Juan Puebla) pp.29-30.-- 11Seminario Internacional "Color en el Diseño y la Arquitectura" pp.32.-- Taller de Pintura con Antonio López E.T.S. de Pamplona, septiembre de 2006 y 2007 (Por Inmacu/ada .liméne: Cabal/ero) pp.32-35.-- Arquitectura y autopsia: análisis gráficos de algunos restos de la inexistente Universidad laboral de Sevilla (Por José Joaquín Parra Bañón) pp.36-37Milán Gómez, A.; Verd Herrero, A.; De San Antonio Gomez, JC.; Grijalba Bengoetxea, A.; Rabasa Díaz, E.; Linares García, F.; García-Gutiérrez Mosteiro, J.... (2008). Reseñas de libros. EGA Expresión Gráfica Arquitectónica. 13(13):4-37. https://doi.org/10.4995/ega.2008.10266OJS437131

    Adaptación a la docencia online de las prácticas preclínicas de Cirugía Bucal I

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    Los cambios en la docencia debido a la pandemia por la COVID-19 ha llevado a la reducción de la presencialidad y a un aumento de la docencia online. Por ello se diseñó este proyecto, cuya finalidad fue la adaptación a la docencia online de las prácticas preclínicas de Cirugía Bucal I. Para el desarrollo de este trabajo se realizaron las rúbricas de evaluación de cada módulo de la asignatura, se elaboraron videos y documentación para subir al campus virtual antes de la realización de la práctica. Finalmente, se elaboraron cuestionarios de evaluación de la satisfacción de los estudiantes y profesorado con esta metodología. Los resultados mostraron una elevada satisfacción de ambos grupos, considerándola una herramienta de utilidad en el aprendizaje y de implementación en cursos posteriores

    Effectiveness of an intervention for improving drug prescription in primary care patients with multimorbidity and polypharmacy:Study protocol of a cluster randomized clinical trial (Multi-PAP project)

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    This study was funded by the Fondo de Investigaciones Sanitarias ISCIII (Grant Numbers PI15/00276, PI15/00572, PI15/00996), REDISSEC (Project Numbers RD12/0001/0012, RD16/0001/0005), and the European Regional Development Fund ("A way to build Europe").Background: Multimorbidity is associated with negative effects both on people's health and on healthcare systems. A key problem linked to multimorbidity is polypharmacy, which in turn is associated with increased risk of partly preventable adverse effects, including mortality. The Ariadne principles describe a model of care based on a thorough assessment of diseases, treatments (and potential interactions), clinical status, context and preferences of patients with multimorbidity, with the aim of prioritizing and sharing realistic treatment goals that guide an individualized management. The aim of this study is to evaluate the effectiveness of a complex intervention that implements the Ariadne principles in a population of young-old patients with multimorbidity and polypharmacy. The intervention seeks to improve the appropriateness of prescribing in primary care (PC), as measured by the medication appropriateness index (MAI) score at 6 and 12months, as compared with usual care. Methods/Design: Design:pragmatic cluster randomized clinical trial. Unit of randomization: family physician (FP). Unit of analysis: patient. Scope: PC health centres in three autonomous communities: Aragon, Madrid, and Andalusia (Spain). Population: patients aged 65-74years with multimorbidity (≥3 chronic diseases) and polypharmacy (≥5 drugs prescribed in ≥3months). Sample size: n=400 (200 per study arm). Intervention: complex intervention based on the implementation of the Ariadne principles with two components: (1) FP training and (2) FP-patient interview. Outcomes: MAI score, health services use, quality of life (Euroqol 5D-5L), pharmacotherapy and adherence to treatment (Morisky-Green, Haynes-Sackett), and clinical and socio-demographic variables. Statistical analysis: primary outcome is the difference in MAI score between T0 and T1 and corresponding 95% confidence interval. Adjustment for confounding factors will be performed by multilevel analysis. All analyses will be carried out in accordance with the intention-to-treat principle. Discussion: It is essential to provide evidence concerning interventions on PC patients with polypharmacy and multimorbidity, conducted in the context of routine clinical practice, and involving young-old patients with significant potential for preventing negative health outcomes. Trial registration: Clinicaltrials.gov, NCT02866799Publisher PDFPeer reviewe
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