989 resultados para Fluid transport


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In radionuclide metrology, Monte Carlo (MC) simulation is widely used to compute parameters associated with primary measurements or calibration factors. Although MC methods are used to estimate uncertainties, the uncertainty associated with radiation transport in MC calculations is usually difficult to estimate. Counting statistics is the most obvious component of MC uncertainty and has to be checked carefully, particularly when variance reduction is used. However, in most cases fluctuations associated with counting statistics can be reduced using sufficient computing power. Cross-section data have intrinsic uncertainties that induce correlations when apparently independent codes are compared. Their effect on the uncertainty of the estimated parameter is difficult to determine and varies widely from case to case. Finally, the most significant uncertainty component for radionuclide applications is usually that associated with the detector geometry. Recent 2D and 3D x-ray imaging tools may be utilized, but comparison with experimental data as well as adjustments of parameters are usually inevitable.

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Objectifs: Le dosage des biomarqueurs du liquide céphalorachidien (LCR) ne fait pas partie des recommandations de la démarche diagnostique de la maladie d'Alzheimer (MA) en France. Nous voulions analyser l'apport de leur dosage en pratique clinique quotidienne. Matériel et méthode: Étude rétrospective observationnelle, portant sur l'ensemble des dosages de biomarqueurs du LCR de la MA effectués entre le 1er novembre 2010 et le 30 septembre 2012 dans l'hôpital de jour (HDJ) et le service de médecine interne gériatrique (SMIG) du centre mémoire de ressources et de recherche (CMRR) des hôpitaux universitaires de Strasbourg (Alsace, France). Résultats: Quatre-vingt-dix-sept patients (femmes : 60,8 % ; âge moyen : 80 ± 6,5 ans) ont été considérés. En HDJ (n = 50), les biomarqueurs étaient utilisés pour le diagnostic positif de MA (64,0 %) ou le diagnostic différentiel entre les démences (36,0 %). Au SMIG (n = 47), leur dosage était effectué afin de confirmer une MA (19,1 %), de rechercher une pathologie cognitive sous-jacente à un syndrome confusionnel (17,0 %) ou pour diagnostiquer une démence chez des patients atteints de pathologies psychiatriques (29,8 %). Si 49,5 % des patients ont eu un diagnostic de MA confirmée, les biomarqueurs ont contribué à infirmer cette étiologie dans 9,2 % des cas. Le doute entre une MA et une autre étiologie persistait cependant encore chez 10 patients. Les analyses comparatives des taux des différents biomarqueurs ont montré que la protéine tau est observée avec un taux significativement plus élevé dans la MA que dans la démence vasculaire (p = 0,003) et à la limite de la significativité pour la maladie de Parkinson (p = 0,06). Le profil observé avec la Ptau est similaire mais avec une significativité atteinte vis-à-vis de la démence de la maladie de Parkinson (p = 0,01). En ce qui concerne l'Aβ1-42, si les taux moyens étaient les plus élevés dans les démences vasculaire et à corps de Lewy, (p < 0,0001 et p < 0,01), ils étaient plus faibles en cas de démence de la maladie de Parkinson mais sans atteindre le seuil de signification (p = 0,12). Conclusion: Cette étude a analysé l'utilisation des biomarqueurs de la MA en pratique courante. Si leur intérêt se positionne actuellement dans le diagnostic de la MA à un stade léger, ces biomarqueurs montrent leur utilité dans les situations où le diagnostic clinique est rendu difficile par un trouble psychiatrique et/ou une confusion, une clinique atypique où lorsque les tests cognitifs sont irréalisables.

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Dans le néphron distal sensible à l'aldostérone, le récepteur aux minéralocorticoïdes (RM) et le récepteur aux glucocorticoids (RG) sont exprimés et peuvent être liés et activés par l'aldostérone et le Cortisol, respectivement. La réabsorption rénale de sodium est principalement contrôlée par le RM. Cependant, des modèles expérimentaux in vitro et in vivo suggèrent que le RG pourrait également jouer un rôle dans le transport rénal du sodium. Afin d'étudier l'implication du RG et/ou du RM exprimés dans les cellules épithéliales adultes dans le transport rénal du sodium, nous avons généré deux modèles de souris, dans lesquelles l'expression du RG (Nr3c1Pax8/LC1) ou du RM (Nr3c2Pax8/LC1) peut être abolie de manière inductible et cela spécifiquement dans les tubules rénaux. Les souris déficientes pour le gène du RM survivent mais développent un phénotype sévère de PHA-1, caractérisé par un retard de croissance, une augmentation des niveaux urinaires de Na+, une diminution de la concentration du Na+ dans le plasma, une hyperkaliémie et une augmentation des niveaux d'aldostérone plasmatique. Ce phénotype empire et devient létal lorsque les souris sont nourries avec une diète déficiente en sodium. Les niveaux d'expression en protéine de NCC, de la forme phosphorylée de NCC et de aENaC sont diminués, alors que l'expression en ARN messager et en protéine du RG est augmentée. Une diète riche en Na+ et pauvre en K+ ne corrige pas la concentration élevée d'aldostérone dans le plasma pour la ramener à des niveaux conformes, mais est suffisante pour corriger la perte de poids et les niveaux anormaux des électrolytes dans le plasma et l'urine. -- In the aldosterone-sensitive distal nephron, both the mineralocorticoid (MR) and the glucocorticoid (GR) receptor are expressed. They can be bound and activated by aldosterone and Cortisol, respectively. Renal Na+ reabsorption is mainly controlled by MR. However, in vitro and in vivo experimental models suggest that GR may play a role in renal Na+ transport. Therefore, to investigate the implication of MR and/or GR in adult epithelial cells in renal sodium transport, we generated inducible renal tubule- specific MR (Nr3c2Pax8/LC1) and GR (Nr3c1Pax8/LC1) knockout mice. MR-deficient mice survived but developed a severe PHA-1 phenotype with failure to thrive, higher urinary Na+, decreased plasma Na+ levels, hyperkalemia and higher levels of plasma aldosterone. This phenotype further worsened and became lethal under a sodium-deficient diet. NCC protein expression and its phosphorylated form, as well as aENaC protein level were downregulated, whereas the mRNA and protein expression of GR was increased. A diet rich in Na+and low in K+ did not normalize plasma aldosterone to control levels, but was sufficient to restore body weight, plasma and urinary electrolytes. Upon switch to a Na+-deficient diet, GR-mutant mice exhibited transient increased urinary Na+ and decreased K+ levels, with transitory higher plasma K+ concentration preceded by a significant increase in plasma aldosterone levels within the 12 hours following diet switch. We found no difference in urinary aldosterone levels, plasma Na+ concentration and plasma corticosterone levels. Moreover, NHE3, NKCC2, NCC

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In geriatrics, driving cessation is addressed within the biopsychosocial model. This has broadened the scope of practitioners, not only in terms of assessing fitness to drive, but also by helping to maintain social engagements and provide support for transport transition. Causes can be addressed at different levels by adapting medication, improving physical health, modifying behaviour, adapting lifestyle, or bringing changes to the environment. This transdisciplinary approach requires an understanding of how different disciplines are linked to each other. This article reviews the philosophical principles of causality between fields and provides a framework for understanding causality within the biopsychosocial model. Understanding interlevel constraints should help practitioners overcome their differences, and favor transversal approaches to driving cessation.

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Some recent studies have characterized the stability of blood variables commonly measured for the Athlete Biological Passport. The aim of this study was to characterize the impact of different shipments conditions and the quality of the results returned by the haematological analyzer. Twenty-two healthy male subjects provided five EDTA tubes each. Four shipment conditions (24, 36, 48, 72 h) under refrigerated conditions were tested and compared to a set of samples left in the laboratory also under refrigerated conditions (group control). All measurements were conducted using two Sysmex XT-2000i analyzers. Haemoglobin concentration, reticulocytes percentage, and OFF-score numerical data were the same for samples analyzed just after collection and after a shipment under refrigerated conditions up to 72 h. Detailed information reported especially by the differential (DIFF) channel scatterplot of the Sysmex XT-2000i indicated that there were signs of blood deterioration, but were not of relevance for the variables used in the Athlete Biological Passport. As long as the cold chain is guaranteed, the time delay between the collection and the analyses of blood variables can be extended. Copyright© 2015 John Wiley & Sons, Ltd.

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This study shows the possibility offered by modern ultra-high performance supercritical fluid chromatography combined with tandem mass spectrometry in doping control analysis. A high throughput screening method was developed for 100 substances belonging to the challenging classes of anabolic agents, hormones and metabolic modulators, synthetic cannabinoids and glucocorticoids, which should be detected at low concentrations in urine. To selectively extract these doping agents from urine, a supported liquid extraction procedure was implemented in a 48-well plate format. At the tested concentration levels ranging from 0.5 to 5 ng/mL, the recoveries were better than 70% for 48-68% of the compounds and higher than 50% for 83-87% of the tested substances. Due to the numerous interferences related to isomers of steroids and ions produced by the loss of water in the electrospray source, the choice of SFC separation conditions was very challenging. After careful optimization, a Diol stationary phase was employed. The total analysis time for the screening assay was only 8 min, and interferences as well as susceptibility to matrix effect (ME) were minimized. With the developed method, about 70% of the compounds had relative ME within the range ±20%, at a concentration of 1 and 5 ng/mL. Finally, limits of detection achieved with the above-described strategy including 5-fold preconcentration were below 0.1 ng/mL for the majority of the tested compounds. Therefore, LODs were systematically better than the minimum required performance levels established by the World anti-doping agency, except for very few metabolites.

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Most aerial parts of the plants are covered by a hydrophobic coating called cuticle. The cuticle is formed of cutin, a complex mixture of esterified fatty acids that are embedded and associated with waxes. The cuticle often appears as a superposition of layers of different composition: The cuticle proper formed of cutin and a mixture of waxes and underneath, the cuticle layer containing cutin, intracuticular waxes and polysaccharides of the cell wall. In addition to its involvement in plant development by preventing organ fusions, the cuticle acts as a barrier to prevent water loss and protect plants against environmental aggressions such as excessive radiation or pathogens attacks. PEC1/AtABCG32 is an ABC transporter from the PDR family involved in cutin biosynthesis. Characterization of the peci mutant in Arabidopsis thaliana showed that PEC1 plays a significant role in the diffusion barrier formation in leaves and petals. The cuticles of leaves and flowers of peci are permeable and the cuticular layer rather than the cuticular proper was altered in the petals, underlining the importance of this particular layer in the maintenance of the diffusion barrier. Chemical analysis on the flower cutin monomer composition of ped mutant revealed a decrease in hydroxylated cutin monomers, suggesting a function of PEC1 in the incorporation of these monomers in the polymer cutin. However, the exact nature of the substrates of PEC1 remained elusive. PEC1 homologues in barley and rice, respectively HvABCG31/EIBI1 and OsABCG31, are also implicated in cuticle biosynthesis. Interestingly, the rice mutant displays more severe phenotypes such as dwarfism and spreading necrosis conducting to the seedling death. In this work, we further characterized osabcg31 mutant and hairpin-RNAi downregulated OsABCG31 plant lines showing reduced growth and cuticle permeability. Our analysis showed a decrease in hydroxylated cutin monomers and severe disruptions in the cuticle, which explain the permeability. Further insights into the function of the cuticle in rice resistance/susceptibility to Pathogens were obtained after inoculation with Magnaporthe oryzae, the fungus responsible for the rice blast disease. Osabcg31 as well as the transgenic lines downregulating OsABCG31 showed increased resistance to the fungus. However, only later steps of infection are reduced . and no impact is obseived on the germination or penetration stages, suggesting that the cuticle disruption per se is not responsible for the resistance. We further investigated the cause of the resistance by analyzing the expression of defense related gene in osabcg31 prior to infection. We found that osabcg31 constitutively express defense related genes, which may explain the resistance, the dwarfism and the cell death. osabcg31 is thus a tool to study the connection between cuticle, plant development and defense signaling networks in rice. The transport function of PEC1 family members is still unknown. In order to link cutin biosynthesis and transport activity, we combined ped mutation with mutations in cutin synthesis related genes. Here, we show that PEC1 acts independently from GPAT4 and GPAT8 pathway and partially overlaps with GPAT6 biosynthesis pathway that leads to the production of hydroxylated C16 cutin precursor 2-Mono(10,16-dihydroxyhexadecanoylJglycerol (2-MHG). In addition, we noticed that despite a comparable cutin monomer composition, ped mutant leaves cuticle are permeable while that of gpat6 mutant are not. This finding raises the possibility of PEC1 being required for the incorporation of C16 hydroxylated monomers and their structural arrangement rather than their direct transport towards the cuticle. A careful investigation of the cuticle permeability, cutin composition and ultrastructure during leave development in Wt plants and ped mutants revealed a possible different regulation of several pathways of cutin biosynthesis and showed the importance of PEC1 function early during leave cuticle maturation. In order to elucidate the transport activity of PEC1, we successfully expressed PEC1 in Nicotiana benthamiana plant system for direct transport experiments. This system will be used to test the PEC 1-dependent transport of potential substrates such as sn-2-monoacylglycerol loaded with a hydroxylated C16 fatty acid. -- Toutes les parties aériennes des plantes sont recouvertes d'une couche hydrophobe appelée «cuticule». Cette cuticule est composée de cutine, un polymère d'acides gras estérifiés, et de cires. La cuticule apparaît souvent sous forme de couches superposées: une première couche extérieure appelée «cuticle proper» formée de cutine et d'un mélange de cires, et une deuxième couche, la «cuticle layer», formée de cutine associée à des cires intracuticulaires et des polysaccharides pariétaux. La cuticule joue le rôle de barrière prévenant contre la perte d'eau et les agressions environnementales. AtABCG32/PEC1 est un transporteur ABC de la famille des PDR impliqué dans la synthèse de la cutine. L'étude du mutant peci d'Arabidopsis thaliana a révélé une fonction de PEC1 dans la formation de la barrière de diffusion. La cuticule des feuilles et fleurs de peci est perméable. Des altérations de la «cuticle layer» ont été démontrées, soulignant son importance dans le maintien de la barrière. L'analyse de la composition de la cutine de peci a montré une réduction spécifique en monomères hydroxylés, suggérant un rôle de PEC1 dans leur incorporation dans la cuticule. Cependant, la nature exacte des substrats de PEC1 n'a pas été identifiée. PEC1 possède deux homologues chez l'orge et le riz, respectivement HvABCG31 et OsABCG31, et qui sont impliqués dans la biosynthèse de la cuticule. Chez le riz, des phénotypes plus sévères ont été observés tels que nanisme et nécroses conduisant à la mort des jeunes plants. Dans cette étude, nous avons continué la caractérisation de osabcg31 ainsi que des lignées de riz sous exprimant le gène OsABCG31 et présentant une cuticule perméable tout en ayant une meilleure croissance. Notre étude a démontré une réduction des monomères hydroxylés de cutine et une désorganisation de la structure de la cuticule, aggravée dans le mutant osabcg31. Ce résultat explique la perméabilité observée. Des mformations P|us approfondies sur l'implication de la cuticule dans la résistance aux pathogènes ont été obtenues après inoculation du mutant osabcg31 et les lignées sous- exprimant OsABCG31 avec une souche virulente de Magnaporthe Oryzae, le champignon responsable de la pyriculariose du riz. Les différentes lignées testées ont démontré une résistance au pathogène. Cependant, seules les étapes tardives de l'infection sont réduites et aucun impact n'est observé sur la germination des spores ou la pénétration du champignon, suggérant que les modifications de la cuticule ne sont pas directement à l'origine de la résistance. L'analyse de l'expression de gènes impliqués dans la résistance à Magnaporthe.oryzae a mis en évidence l'expression constitutive de ces gènes en l'absence de tout contact avec le pathogène. Ceci explique la résistance, le nanisme et la mort cellulaire observés. Ainsi, osabcg31 représente un outil efficace pour l'étude intégrée des systèmes de régulation de la défense, de développement des plantes et la cuticule. La nature des substrats transportés par PEC1/AtABCG32 reste inconnue. Dans le but d'établir une liaison entre biosynthèse de cutine et transport des précurseurs par PEC1, la mutation peci a été combinée avec des mutants impliqués dans différentes voies de biosynthèse. Cette étude a démontré une fonction indépendante de PEC1 de la voie de biosynthèse impliquant les enzymes GPAT4 et GPAT8, et une fonction partiellement indépendante de la voie impliquant GPAT6 qui mène à la production de précurseurs sn-2- monoacylglycerol chargés en acides gras en C16 (2-MHG). De plus, malgré un profil similaire en monomères de cutine, gpat6 conserve une cuticule imperméable alors que celle de PEC1 est perméable. Ceci suggère que PEC1 est nécessaire à l'incorporation des monomères en C16 et leur arrangement structurel plutôt que simplement à leur transport direct. L'étude approfondie de la perméabilité cuticulaire, de la structure ainsi que de la composition en cutine pendant le développement des feuilles de peci et la plante sauvage a révélé l'existence de différentes régulations des voies de biosynthèses des monomères et a démontré l'importance de PEC1 dans les premières étapes de la mise en place de la cuticule. Pour identifier les substrats transportés, l'expression de PEC1 chez le système hétérologue Nicotiana benthamiana a été conduite avec succès. Ce système sera utilisé pour tester le transport de substrats potentiels tels que le sn-2-monoacylglycerol chargé en acide gras en C16.

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It is often assumed that total head losses in a sand filter are solely due to the filtration media and that there are analytical solutions, such as the Ergun equation, to compute them. However, total head losses are also due to auxiliary elements (inlet and outlet pipes and filter nozzles), which produce undesirable head losses because they increase energy requirements without contributing to the filtration process. In this study, ANSYS Fluent version 6.3, a commercial computational fluid dynamics (CFD) software program, was used to compute head losses in different parts of a sand filter. Six different numerical filter models of varying complexities were used to understand the hydraulic behavior of the several filter elements and their importance in total head losses. The simulation results show that 84.6% of these were caused by the sand bed and 15.4% were due to auxiliary elements (4.4% in the outlet and inlet pipes, and 11.0% in the perforated plate and nozzles). Simulation results with different models show the important role of the nozzles in the hydraulic behavior of the sand filter. The relationship between the passing area through the nozzles and the passing area through the perforated plate is an important design parameter for the reduction of total head losses. A reduced relationship caused by nozzle clogging would disproportionately increase the total head losses in the sand filter

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Que ce soit d'un point de vue, urbanistique, social, ou encore de la gouvernance, l'évolution des villes est un défi majeur de nos sociétés contemporaines. En offrant la possibilité d'analyser des configurations spatiales et sociales existantes ou en tentant de simuler celles à venir, les systèmes d'information géographique sont devenus incontournables dans la gestion et dans la planification urbaine. En cinq ans la population de la ville de Lausanne est passée de 134'700 à 140'570 habitants, alors que les effectifs de l'école publique ont crû de 12'200 à 13'500 élèves. Cet accroissement démographique associé à un vaste processus d'harmonisation de la scolarité obligatoire en Suisse ont amené le Service des écoles à mettre en place et à développer en collaboration avec l'université de Lausanne des solutions SIG à même de répondre à différentes problématiques spatiales. Établies en 1989, les limites des établissements scolaires (bassins de recrutement) ont dû être redéfinies afin de les réadapter aux réalités d'un paysage urbain et politique en pleine mutation. Dans un contexte de mobilité et de durabilité, un système d'attribution de subventions pour les transports publics basé sur la distance domicile-école et sur l'âge des écoliers, a été conçu. La réalisation de ces projets a nécessité la construction de bases de données géographiques ainsi que l'élaboration de nouvelles méthodes d'analyses exposées dans ce travail. Cette thèse s'est ainsi faite selon une dialectique permanente entre recherches théoriques et nécessités pratiques. La première partie de ce travail porte sur l'analyse du réseau piéton de la ville. La morphologie du réseau est investiguée au travers d'approches multi-échelles du concept de centralité. La première conception, nommée sinuo-centralité ("straightness centrality"), stipule qu'être central c'est être relié aux autres en ligne droite. La deuxième, sans doute plus intuitive, est intitulée centricité ("closeness centrality") et exprime le fait qu'être central c'est être proche des autres (fig. 1, II). Les méthodes développées ont pour but d'évaluer la connectivité et la marchabilité du réseau, tout en suggérant de possibles améliorations (création de raccourcis piétons). Le troisième et dernier volet théorique expose et développe un algorithme de transport optimal régularisé. En minimisant la distance domicile-école et en respectant la taille des écoles, l'algorithme permet de réaliser des scénarios d'enclassement. L'implémentation des multiplicateurs de Lagrange offre une visualisation du "coût spatial" des infrastructures scolaires et des lieux de résidence des écoliers. La deuxième partie de cette thèse retrace les aspects principaux de trois projets réalisés dans le cadre de la gestion scolaire. À savoir : la conception d'un système d'attribution de subventions pour les transports publics, la redéfinition de la carte scolaire, ou encore la simulation des flux d'élèves se rendant à l'école à pied. *** May it be from an urbanistic, a social or from a governance point of view, the evolution of cities is a major challenge in our contemporary societies. By giving the opportunity to analyse spatial and social configurations or attempting to simulate future ones, geographic information systems cannot be overlooked in urban planning and management. In five years, the population of the city of Lausanne has grown from 134'700 to 140'570 inhabitants while the numbers in public schools have increased from 12'200 to 13'500 students. Associated to a considerable harmonisation process of compulsory schooling in Switzerland, this demographic rise has driven schooling services, in collaboration with the University of Lausanne, to set up and develop GIS capable of tackling various spatial issues. Established in 1989, the school districts had to be altered so that they might fit the reality of a continuously changing urban and political landscape. In a context of mobility and durability, an attribution system for public transport subventions based on the distance between residence and school and on the age of the students was designed. The implementation of these projects required the built of geographical databases as well as the elaboration of new analysis methods exposed in this thesis. The first part of this work focuses on the analysis of the city's pedestrian network. Its morphology is investigated through multi-scale approaches of the concept of centrality. The first conception, named the straightness centrality, stipulates that being central is being connected to the others in a straight line. The second, undoubtedly more intuitive, is called closeness centrality and expresses the fact that being central is being close to the others. The goal of the methods developed is to evaluate the connectivity and walkability of the network along with suggesting possible improvements (creation of pedestrian shortcuts).The third and final theoretical section exposes and develops an algorithm of regularised optimal transport. By minimising home to school distances and by respecting school capacity, the algorithm enables the production of student allocation scheme. The implementation of the Lagrange multipliers offers a visualisation of the spatial cost associated to the schooling infrastructures and to the student home locations. The second part of this thesis recounts the principal aspects of three projects fulfilled in the context of school management. It focuses namely on the built of an attribution system for public transport subventions, a school redistricting process and on simulating student pedestrian flows.

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The paper analyses the link between human capital and regional economic growth in the European Union. Using different indicat The importance of effective and efficient mobility in large cities is becoming essential for planners and citizens due to its impact in terms of social, economic and geographic development. The aim of this research is to determine factors explaining urban transport systems by estimating aggregate supply and demand equations for 45 large European cities. Supply and Demand equations are separately and jointly determined using OLS and SUR estimation models. On one hand, our findings suggest the importance of economic variables on the supply of public transport. On the other, we highlight the role of those factors influencing the generalized cost of transport as main drivers of demand for public transit. Additionally, regional variables are introduced to capture institutional heterogeneity in this service, and we find that regional patterns are powerful explanatory determinants of urban transportation systems in Europe.

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This article, in reviewing the longrunning US debate on speed limits, illustrates how a different valuation of the trade-off between private mobility needs and safety concerns can shape transport policies. It is argued that the regulatory decentralization debate, together with the speed limit in force in each state, obey the social preferences and valuation given to this tradeoff. Such a view is consistent with evidence that higher speed limits are to be found in states with greater private mobility needs, even though their fatality rates might be among the highest in the country. By contrast, lower speed limits and supporters of a low national speed limit are to be found in states that show a greater concern for safety outcomes and which are less dependent on private mobility. By reviewing these events and examining the role played by the main actors and analyzing their motivations, the article identifies important lessons for similar future discussions on transport policy.

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This paper wants to show a solution for mobility in public transport. Nowadays, the high number of mobile devices with wireless geolocation and Internet data connection has become commonly used tools, as well as partial solutions to facilitate public transport focused on one means of transport (Bus, Underground ...). We collect information from public transport (means of transport, routes, schedules, fare information ...) and adapt it to different users (residents, visitors, public service staff ...). MoveOnApp is the solution adapting its user interface: finding nearby stops, planning a route, knowing schedules or real time service (connecting to the available services), or showing the route of the line. The system could incorporate new cities and regions, or new means of transport with updating service; at first we offered information of public transport from Palma (Majorca Island, Spain): moveOn Palma.

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This thesis is focused on process intensification. Several significant problems and applications of this theme are covered. Process intensification is nowadays one of the most popular trends in chemical engineering and attempts have been made to develop a general, systematic methodology for intensification. This seems, however, to be very difficult, because intensified processes are often based on creativity and novel ideas. Monolith reactors and microreactors are successful examples of process intensification. They are usually multichannel devices in which a proper feed technique is important for creating even fluid distribution into the channels. Two different feed techniques were tested for monoliths. In the first technique a shower method was implemented by means of perforated plates. The second technique was a dispersion method using static mixers. Both techniques offered stable operation and uniform fluid distribution. The dispersion method enabled a wider operational range in terms of liquid superficial velocity. Using dispersion method, a volumetric gas-liquid mass transfer coefficient of 2 s-1 was reached. Flow patterns play a significant role in terms of the mixing performance of micromixers. Although the geometry of a T-mixer is simple, channel configurations and dimensions had a clear effect on mixing efficiency. The flow in the microchannel was laminar, but the formation of vortices promoted mixing in micro T-mixers. The generation of vortices was dependent on the channel dimensions, configurations and flow rate. Microreactors offer a high ratio of surface area to volume. Surface forces and interactions between fluids and surfaces are, therefore, often dominant factors. In certain cases, the interactions can be effectively utilised. Different wetting properties of solid materials (PTFE and stainless steel) were applied in the separation of immiscible liquid phases. A micro-scale plate coalescer with hydrophilic and hydrophobic surfaces was used for the continuous separation of organic and aqueous phases. Complete phase separation occurred in less than 20 seconds, whereas the separation time by settling exceeded 30 min. Fluid flows can be also intensified in suitable conditions. By adding certain additives into turbulent fluid flow, it was possible to reduce friction (drag) by 40 %. Drag reduction decreases frictional pressure drop in pipelines which leads to remarkable energy savings and decreases the size or number of pumping facilities required, e.g., in oil transport pipes. Process intensification enables operation often under more optimal conditions. The consequent cost savings from reduced use of raw materials and reduced waste lead to greater economic benefits in processing.

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Samlingen med signum HB Xg finns vid huvudbiblioteket och innehåller litteratur om olika transport- och trafikmedel, om sjöfart, om posttrafik etc. till och med år 1999. Vid Sjöhistoriska institutet, Forum Marinum, finns litteratur om sjöfart, se http://www.abo.fi/instut/sjohistoriska/ Litteratur om kommunikationer har ingått i bokdonationer såväl från hemlandet som från Sverige. Friexemplar som erhållits från år 1919 samt inköp har kompletterat samlingen. Litteraturen i samlingen söks i Alma med sökfunktionen Signum och söktermen HB Xg. En del litteratur tryckt före 1980 söks manuellt i den systematiska katalogen, men retroaktiv inmatning i Alma av litteratur tryckt mellan 1830 och 1979 pågår. Från och med år 2000 ingår litteraturen vid huvudbiblioteket om transport, trafik och post i en numerus currens-samling.

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Within the scope of the TECNOLONIAL (HAR2008-02834/HIST) project, an archaeologi- cal and archaeometric research is being conduct- ed in order to clarify and systematize transport jars production in the Iberian peninsula and their distribution abroad, especially to the Americas, from the 15th to the 17th century. The production centre of Seville, in the Crown of Castile, produced large glazed and unglazed transport jars, called botijas, which were mainly devoted to the Atlantic trade network. The pres- ent study accounts for the first results obtained from an initial sample of 34 transport jars dated around the 15th-16th centuries from the produc- tion centre of Seville and the reception site of Santa María de la Antigua del Darién (gulf of Urabá, Colombia). This latter site is especially significant since it was the first Spanish founda- tion (1510) in continental America that obtained the title of town, and was the seat for the Governor of the new region called Castilla de Oro, as well as for the first diocese. All individuals were analyzed by means of x-ray fluorescence and diffraction analyses and then compared with the majolica production database from Seville. The results enabled us to define the first refer- ence groups for such modern transport jars, and to get a first insight into the jars coming to the Americas in the early 16th century whose prove- nance can be linked to Seville, but not Triana.