999 resultados para Road materials Permeability


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El desenvolupament del projecte ens ha permès de crear materials per a l´aprenentatge autònom de la interpretació de conferències així com d´un material d´acompanyament i suport del procés d´aprenentatge no presencial. Aquests materials s´integren en les assignatures d´interpretació del Grau en Traducció i Interpretació i serveixen perquè els estudiants continuïn fent un treball guiat fora de l´aula. Es pot considerar també un material de suport a les classes presencials. Els materials desenvolupats cobreixen les cinc llengües dels nostres estudis (català, castellà, anglès, alemany i francès) i estan organitzats en dos blocs diferenciats: itineraris d´aprenentatge i banc de discursos. Aquesta divisió permet a l´estudiant treballar seguint dues opcions diferenciades: a) a partir d´una seqüenciació guiada de tasques; b) abordant directament la interpretació d´un discurs oral. El projecte s'ha dut a terme entre les universitats Pompeu Fabra i Autònoma de Barcelona, durant el període 2007- 2009.

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Recently, Revil & Florsch proposed a novel mechanistic model based on the polarization of the Stern layer relating the permeability of granular media to their spectral induced polarization (SIP) characteristics based on the formation of polarized cells around individual grains. To explore the practical validity of this model, we compare it to pertinent laboratory measurements on samples of quartz sands with a wide range of granulometric characteristics. In particular, we measure the hydraulic and SIP characteristics of all samples both in their loose, non-compacted and compacted states, which might allow for the detection of polarization processes that are independent of the grain size. We first verify the underlying grain size/permeability relationship upon which the model of Revil & Florsch is based and then proceed to compare the observed and predicted permeability values for our samples by substituting the grain size characteristics by corresponding SIP parameters, notably the so-called Cole-Cole time constant. In doing so, we also asses the quantitative impact of an observed shift in the Cole-Cole time constant related to textural variations in the samples and observe that changes related to the compaction of the samples are not relevant for the corresponding permeability predictions. We find that the proposed model does indeed provide an adequate prediction of the overall trend of the observed permeability values, but underestimates their actual values by approximately one order-of-magnitude. This discrepancy in turn points to the potential importance of phenomena, which are currently not accounted for in the model and which tend to reduce the characteristic size of the prevailing polarization cells compared to the considered model, such as, for example, membrane polarization, contacts of double-layers of neighbouring grains, and incorrect estimation of the size of the polarized cells because of the irregularity of natural sand grains.

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En aquest projecte es presenta un estudi sobre punxonats i esbocats per a materials d’Alt límit elàstic (Acers AHSS; Advanced High Strength Steels), amb l’objectiu d’aconseguir saber quin és el millor procés de tall per aconseguir esbocats correctes. Utilitzant la premsa hidràulica de la Fundació Centre Tecnològic de Manresa (CTM) es realitza el punxonat i els esbocats a tots els materials per tal d’avaluar el seu comportament alhora de ser esbocats. A partir d’aquests resultats obtindrem les gràfiques de ràtio d’esbocat per a cadascun dels materials en els diferents sentits de esbocat. Com a mètode alternatiu del procés de tall, es realitzen unes mostres amb tall per aigua. S’observarà si els esbocats trenquen o no trenquen i en quines condicions ho fan. Una vegada realitzats aquests assajos, es procedirà a realitzar l’estudi de microdureses amb un indentador Vickers per tal de comprovar l’afectació de l’operació de tall en la microestructura del material. Es realitzarà també algun perfil de dureses utilitzant el Nanoindentador. Per finalitzar el projecte, s’inclourà un apartat de conclusions i un estudi mediambiental produït com a conseqüència de l’elaboració del projecte, així com un pressupost total d’aquest.

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Edició crítica del París e Viana català que té com a testimoni de base l'incunable de Girona de 1495, que es conserva a la Biblioteca Reial de Copenhaguen. El treball conté una anàlisi comparativa de les variants de l'edició de Girona i de les de l'edició de Barcelona. Es desmenteix la hipòtesi de Cátedra (1986: 37-38), segons la qual el Curial e Güelfa podria dependre del París e Viana i s'argumenta la inconveniència de classificar aquesta novel·la cavalleresca com a ficció sentimental. Les notes permeten resseguir els motius literaris comuns que constitueixen el relat

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The Road Safety Authority has responsibility for co-ordinating the development of Ireland’s Road Safety Strategy.  The Government’s road safety target of no more than 252 deaths per annum by the end of 2012 was achieved in 2009, when the number of road collision deaths in Ireland fell to 239.  The reduction in the number of fatalities was achieved through robust actions in terms of education and awareness, road engineering, and enforcement, including significant legislative milestones.  The challenge is now to ensure that the impact of these measures on collision levels is sustained and enhanced into the future through continuous education, enforcement and road engineering measures and initiatives. IPH welcomes the opportunity to respond to this consultation given the significant burden of injury, disability and mortality associated with road traffic collisions on the island of Ireland.  IPH supports the development of evidence-based strategies and actions which can maintain a transport system, in which the safety of all road users is paramount. 

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The Department of Environment (NI)  recently held a consultation on preparing a new road safety strategy for Northern Ireland which will cover the years 2010 to 2020.  The consultation ran from 16 March 2010 to 15 June 2010.  The consultation paper outlined key challenges to be addressed over the lifetime of the strategy and proposed a number of action measures which have been agreed by the statutory road safety partners.  Views were invited on preparing a new road safety strategy for Northern Ireland that will shape the way ahead for safety on roads over the next decade.

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BACKGROUND: Food allergy is a common allergic disorder--especially in early childhood. The avoidance of the allergenic food is the only available method to prevent further reactions in sensitized patients. A better understanding of the immunologic mechanisms involved in this reaction would help to develop therapeutic approaches applicable to the prevention of food allergy. OBJECTIVE: To establish a multi-cell in vitro model of sensitized intestinal epithelium that mimics the intestinal epithelial barrier to study the capacity of probiotic microorganisms to modulate permeability, translocation and immunoreactivity of ovalbumin (OVA) used as a model antigen. METHODS: Polarized Caco-2 cell monolayers were conditioned by basolateral basophils and used to examine apical to basolateral transport of OVA by ELISA. Activation of basophils with translocated OVA was measured by beta-hexosaminidase release assay. This experimental setting was used to assess how microorganisms added apically affected these parameters. Basolateral secretion of cytokine/chemokines by polarized Caco-2 cell monolayers was analysed by ELISA. RESULTS: Basophils loaded with OVA-specific IgE responded to OVA in a dose-dependent manner. OVA transported across polarized Caco-2 cell monolayers was found to trigger basolateral basophil activation. Microorganisms including lactobacilli and Escherichia coli increased transepithelial electrical resistance while promoting OVA passage capable to trigger basophil activation. Non-inflammatory levels of IL-8 and thymic stromal lymphopoietin were produced basolaterally by Caco-2 cells exposed to microorganisms. CONCLUSION: The complex model designed in here is adequate to learn about the consequence of the interaction between microorganisms and epithelial cells vis-a-vis the barrier function and antigen translocation, two parameters essential to mucosal homeostasis. It can further serve as a direct tool to search for microorganisms with anti-allergic and anti-inflammatory properties.

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Para medir los coeficientes de transmisión y reflexión, S21 y S11, de diferentes materiales o muestras planas, se usa un sistema de toma de medidas en espacio libre operando banda W (75 – 110 GHz). Usando estos parámetros, S21 y S11, podemos calcular la permitividad dieléctrica relativa compleja (Er ) y la permeabilidad magnética relativa compleja (μr) mediante un proceso llamado NRW (Nicolson-Ross-Weir). El sistema para medir consiste en dos antenas de bocina, una transmisora y otra receptora, dos espejos con los que obtenemos una onda plana para medir las propiedades del material y un ordenador o dispositivo que calcula los resultados. Este dispositivo requiere de calibración para la obtención de resultados óptimos. Dicho sistema se puede simular de manera ideal con un software llamado ADS (Assistance Design System) para el estudio y comparación de grosores, permitividades dieléctricas relativas y permeabilidades magnéticas relativas de los materiales en función de la frecuencia.

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L'objectiu principal del treball de recerca és el disseny de dos crèdits variables, matèries optatives dins de l'Educació Secundària Obligatòria, entorn de la cultura grega clàssica.

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Reducing comparative optimism regarding risk perceptions in traffic accidents has been proven to be particularly difficult (Delhomme, 2000). This is unfortunate because comparative optimism is assumed to impede preventive action. The present study tested whether a road safety training course could reduce drivers' comparative optimism in high control situations. Results show that the training course efficiently reduced comparative optimism in high control, but not in low control situations. Mechanisms underlying this finding and implications for the design of road safety training courses are discussed.

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Purpose:In the retina, the balance between pro- and anti-angiogenic factors is critical for angiogenesis control but is also involved in cell survival and maintenance. For instance, the anti-angiogenic factor PEDF is neuroprotective for photoreceptors (PRs) in models of retinal degeneration. We previously reported upregulation of VEGF (24h to 48h post lesion) in the light-damage (LD) model. Furthermore, systemic delivery of PEDF, as well as lentiviral gene transfer of an anti-VEGF antibody rescue PRs from cell death. Studies in vitro show that VEGF induces retinal endothelial cells apoptosis via the alteration of the Akt1/p38 MAPK signalling pathway under hypoxic conditions. Thus, in this study, we investigate the effect of high levels of VEGF on retinal pigmented epithelium (RPE) permeability and molecular targets expression after light-induced PR degeneration. Methods:To characterize the action of VEGF in the retina during the course of LD, we exposed adult Balb/c mice to 5'000 lux for 1h, and we collected neural retinas and eye-cups (containing RPE) at different time points after the LD. We analysed protein expression by Elisa and Western blotting. In order to study RPE cell permeability after the LD we stained β-catenin on flat mounted RPE. Results:In the neural retina, preliminary results indicate that high levels of VEGF induce a significant upregulation of VEGF receptor 2, whereas VEGF receptor 1 expression is decreased. Concomitantly with VEGF upregulation, LD increases the Src phosphorylation between 24h to 48h. Furthermore, we observe that β-catenin translocates to the cytoplasm of RPE cells between 24h to 36h after the lesion, indicating an increase on the RPE permeability, which could contribute indirectly to the deleterious effect of VEGF observed during light-induced PR apoptosis. Conclusions:This study further involves VEGF in LD and highlights the prime importance of angiogenic factor balance for PR survival. Our results suggest that PR apoptosis is augmented by RPE cell permeability, which may induce high level of VEGF and could be deleterious. The specific action of RPE permeability on PR survival and the role of Src in the retina are under investigation.

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CONSOLIDATED SALARY SCALES IN ACCORDANCE WITH CLAUSE 2.31 OF THE HADDINGTON ROAD AGREEMENT These scales must be read in conjunction with Department of Health Circular 3/2014 With reference to Clause 2.31 of the Haddington Road Agreement (HRA) which addresses the remuneration of new entrant grades who entered the Public Service on or after 1 January 2011 and were subject to Department of Health Circular 2/2011 dated 24 March 2011.   New entrants to health sector recruitment grades, who were subject to the 2011 reduced pay rates will be assimilated to the revised/merged incremental payscale as and from 1 November 2013. Download the document here

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The application of two approaches for high-throughput, high-resolution X-ray phase contrast tomographic imaging being used at the tomographic microscopy and coherent radiology experiments (TOMCAT) beamline of the SLS is discussed and illustrated. Differential phase contrast (DPC) imaging, using a grating interferometer and a phase-stepping technique, is integrated into the beamline environment at TOMCAT in terms of the fast acquisition and reconstruction of data and the availability to scan samples within an aqueous environment. A second phase contrast method is a modified transfer of intensity approach that can yield the 3D distribution of the decrement of the refractive index of a weakly absorbing object from a single tomographic dataset. The two methods are complementary to one another: the DPC method is characterised by a higher sensitivity and by moderate resolution with larger samples; the modified transfer of intensity approach is particularly suited for small specimens when high resolution (around 1 mu m) is required. Both are being applied to investigations in the biological and materials science fields.

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In this paper, a phenomenologically motivated magneto-mechanically coupled finite strain elastic framework for simulating the curing process of polymers in the presence of a magnetic load is proposed. This approach is in line with previous works by Hossain and co-workers on finite strain curing modelling framework for the purely mechanical polymer curing (Hossain et al., 2009b). The proposed thermodynamically consistent approach is independent of any particular free energy function that may be used for the fully-cured magneto-sensitive polymer modelling, i.e. any phenomenological or micromechanical-inspired free energy can be inserted into the main modelling framework. For the fabrication of magneto-sensitive polymers, micron-size ferromagnetic particles are mixed with the liquid matrix material in the uncured stage. The particles align in a preferred direction with the application of a magnetic field during the curing process. The polymer curing process is a complex (visco) elastic process that transforms a fluid to a solid with time. Such transformation process is modelled by an appropriate constitutive relation which takes into account the temporal evolution of the material parameters appearing in a particular energy function. For demonstration in this work, a frequently used energy function is chosen, i.e. the classical Mooney-Rivlin free energy enhanced by coupling terms. Several representative numerical examples are demonstrated that prove the capability of our approach to correctly capture common features in polymers undergoing curing processes in the presence of a magneto-mechanical coupled load.

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Freshwater snails belonging to the genus Biomphalaria act as intermediate hosts for the parasite trematode Schistosoma mansoni in Africa and in the neotropical region. Identification of such molluscs is carried out based on morphological characters and the presence of cercariae is verified through squeezing snails between two glass slides or by exposing them to artificial light. However, sometimes, the material collected includes molluscs with decomposed bodies or, yet, only empty shells, which precludes their identification and S. mansoni detection. Due to these difficulties, we have developed a methodology in which DNA may be extracted from traces of organic material from inside shells in order to identify molluscs through polymerase chain reaction and restriction fragment length polymorphism and to detect S. mansoni into these snails, by using low stringency polymerase chain reaction. Species-specific profiles obtained from B. glabrata, B. straminea, and B. tenagophila snails and their shells, maintained in laboratory for ten years, showed the same profiles. S. mansoni profiles showed to be present in shell specimens as far as the eighth week after being removed from aquarium.