979 resultados para Distributed Mobility Context


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The goal of this paper is twofold: first, we aim to assess the role played by inventors’ cross-regional mobility and networks of collaboration in fostering knowledge diffusion across regions and subsequent innovation. Second, we intend to evaluate the feasibility of using mobility and networks information to build cross-regional interaction matrices to be used within the spatial econometrics toolbox. To do so, we depart from a knowledge production function where regional innovation intensity is a function not only of the own regional innovation inputs but also external accessible R&D gained through interregional interactions. Differently from much of the previous literature, cross-section gravity models of mobility and networks are estimated to use the fitted values to build our ‘spatial’ weights matrices, which characterize the intensity of knowledge interactions across a panel of 269 regions covering most European countries over 6 years.

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L'objecte del projecte és estudiar en profunditat els sistemes gestors de bases de dates en l'àmbit de la web semàntica. Aquests sistemes són gestors de bases de dades especialitzats en l'emmagatzematge i tractament de dades semàntiques, tot tenint en compte les peculiaritats d'aquestes. Per tal d'aprofundir en la matèria, el projecte es divideix en dues parts principals. En la primera es recerca l'estat de l'art, fent un estudi comparatiu entre els magatzems semàntics més coneguts en l'actualitat. En la segona part s'estudia en profunditat un d'aquests magatzems (Virtuoso Universal Server).

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Through this study, we will measure how the collective MPI operations behaves in virtual and physical clusters, and its impact on the application performance. As we stated before, we will use as a test case the Weather Research and Forecasting simulations.

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The identification of mycobacteria is essential because tuberculosis (TB) and mycobacteriosis are clinically indistinguishable and require different therapeutic regimens. The traditional phenotypic method is time consuming and may last up to 60 days. Indeed, rapid, affordable, specific and easy-to-perform identification methods are needed. We have previously described a polymerase chain reaction-based method called a mycobacteria mobility shift assay (MMSA) that was designed for Mycobacterium tuberculosis complex (MTC) and nontuberculous mycobacteria (NTM) species identification. The aim of this study was to assess the MMSA for the identification of MTC and NTM clinical isolates and to compare its performance with that of the PRA-hsp65 method. A total of 204 clinical isolates (102 NTM and 102 MTC) were identified by the MMSA and PRA-hsp65. For isolates for which these methods gave discordant results, definitive species identification was obtained by sequencing fragments of the 16S rRNA and hsp65 genes. Both methods correctly identified all MTC isolates. Among the NTM isolates, the MMSA alone assigned 94 (92.2%) to a complex or species, whereas the PRA-hsp65 method assigned 100% to a species. A 91.5% agreement was observed for the 94 NTM isolates identified by both methods. The MMSA provided correct identification for 96.8% of the NTM isolates compared with 94.7% for PRA-hsp65. The MMSA is a suitable auxiliary method for routine use for the rapid identification of mycobacteria.

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We want to shed some light on the development of person mobility by analysing the repeated cross-sectional data of the four National Travel Surveys (NTS) that were conducted in Germany since the mid seventies. The above mentioned driving forces operate on different levels of the system that generates the spatial behaviour we observe: Travel demand is derived from the needs and desires of individuals to participate in spatially separated activities. Individuals organise their lives in an interactive process within the context they live in, using given infrastructure. Essential determinants of their demand are the individual's socio-demographic characteristics, but also the opportunities and constraints defined by the household and the environment are relevant for the behaviour which ultimately can be realised. In order to fully capture the context which determines individual behaviour, the (nested) hierarchy of persons within households within spatial settings has to be considered. The data we will use for our analysis contains information on these three levels. With the analysis of this micro-data we attempt to improve our understanding of the afore subsumed macro developments. In addition we will investigate the prediction power of a few classic sociodemographic variables for the daily travel distance of individuals in the four NTS data sets, with a focus on the evolution of this predictive power. The additional task to correctly measure distances travelled by means of the NTS is threatened by the fact that although these surveys measure the same variables, different sampling designs and data collection procedures were used. So the aim of the analysis is also to detect variables whose control corrects for the known measurement error, as a prerequisite to apply appropriate models in order to better understand the development of individual travel behaviour in a multilevel context. This task is complicated by the fact that variables that inform on survey procedures and outcomes are only provided with the data set for 2002 (see Infas and DIW Berlin, 2003).

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Abstract Peroxisome Proliferator-Activated Receptors (PPARs) form a family of three nuclear receptors regulating important cellular and metabolic functions. PPARs control gene expression by directly binding to target promoters as heterodimers with the Retinoid X Receptor (RXR), and their transcriptional activity is enhanced upon activation by natural or pharmacological ligands. The binding of PPAR/RXR heterodimers on target promoters allows the anchoring of a series of coactivators and corepressors involved in promoter remodeling and the recruitment of the transcription machinery. The transcriptional output finally depends on a complex interplay between (i) the respective expression levels of PPARs, RXRs and of other nuclear receptors competing for DNA binding and RXR recruitment, (ii) the availability and the nature of PPAR and RXR ligands, (iii) the expression levels and the nature of the different coactivators and corepressors and (iv) the sequence and the epigenetic status of the promoter. Understanding how all these factors and signals integrate and fine-tune transcription remains a challenge but is necessary to understand the specificity of the physiological functions regulated by PPARs. The work presented herein focuses on the molecular mechanisms of PPAR action and aims at understanding how the interactions and mobility of the receptor modulate transcription in the physiological context of a living cell: Such observations in vivo rely on the use of engineered fluorescent protein chimeras and require the development and the application of complementary imaging techniques such as Fluorescence Recovery After Photobleaching (FRAP), Fluorescence Resonance Energy Transfer (FRET) and Fluorescence Correlation Spectroscopy (FCS). Using such techniques, PPARs are shown to reside solely in the nucleus where they are constitutively associated with RXR but transcriptional activation by ligand binding -does not promote the formation of sub-nuclear structures as observed with other nuclear receptors. In addition, the engagement of unliganded PPARs in large complexes of cofactors in living cells provides a molecular basis for their ligand-independent activity. Ligand binding reduces receptor diffusion by promoting the recruitment of coactivators which further enlarge the size of PPAR complexes to acquire full transcriptional competence. Using these molecular approaches, we deciphered the molecular mechanisms through which phthalates, a class of pollutants from the plastic industry, interfere with PPARγ signaling. Mono-ethyl-hexyl-phthalate (MEHP) binding induces the recruitment of a specific subset of cofactors and translates into the expression of a specific subset of target genes, the transcriptional output being strongly conditioned by the differentiation status of the cell. This selective PPARγ modulation induces limited adipogenic effects in cellular models while exposure to phthalates in animal models leads to protective effects on glucose tolerance and diet-induced obesity. These results demonstrate that phthalates influence lipid and carbohydrate metabolism through complex mechanisms which most likely involve PPARγ but also probably PPARα and PPARß, Altogether, the molecular and physiological demonstration of the interference of pollutants with PPAR action outlines an important role of chemical exposure in metabolic regulations. Résumé Les PPARs (Peroxisome Proliferator-Activated Receptors) forment une famille de récepteurs nucléaires qui régulent des fonctions cellulaires et métaboliques importantes. Les PPARs contrôlent l'expression des gènes en se liant directement à leurs promoteurs sous forme d'hétérodimères avec les récepteurs RXR (Retinoid X Receptor), et leur activité transcriptionnelle est stimulée par la liaison de ligands naturels ou pharmacologiques. L'association des hétérodimères PPAR/RXR avec les promoteurs des gènes cibles permet le recrutement de coactivateurs et de corépresseurs qui vont permettre le remodelage de la chromatine et le recrutement de la machinerie transcriptionnelle. Les actions transcriptionnelles du récepteur dépendent toutefois d'interactions complexes qui sont régulées par (i) le niveau d'expression des PPARs, des RXRs et d'autres récepteurs nucléaires entrant en compétition pour la liaison à l'ADN et l'association avec RXR, (ii) la disponibilité et la nature de ligands de PPAR et de RXR, (iii) les niveaux d'expression et la nature des différents coactivateurs et corépresseurs et (iv) la séquence et le marquage épigénétique des promoteurs. La compréhension des mécanismes qui permettent d'intégrer ces aspects pour assurer une régulation fine de l'activité transcriptionnelle est un défi qu'il est nécessaire de relever pour comprendre la spécificité des fonctions physiologiques régulées par les PPARs. Ce travail concerne l'étude des mécanismes d'action moléculaire des PPARs et vise à mieux comprendre comment les interactions du récepteur avec d'autres protéines ainsi que la mobilité de ce dernier régulent son activité transcriptionnelle dans le contexte physiologique des cellules vivantes. De telles observations reposent sur l'emploi de protéines fusionnées à des protéines fluorescentes ainsi que sur le développement et l'utilisation de techniques d'imagerie complémentaires telles que le FRAP (Fluorescence Recovery After Photobleaching), le FRET (Fluorescence Resonance Energy Transfer) ou la FCS (Fluorescence Corrélation Spectroscopy). En appliquant ces méthodes, nous avons pu montrer que les PPARs résident toujours dans le noyau où ils sont associés de manière constitutive à RXR, mais que l'ajout de ligand n'induit pas la formation de structures sub-nucléaires comme cela a pu être décrit pour d'autres récepteurs nucléaires. De plus, les PPARs sont engagés dans de larges complexes protéiques de cofacteurs en absence de ligand, ce qui procure une explication moléculaire à leur activité ligand-indépendante. La liaison du ligand réduit la vitesse de diffusion du récepteur en induisant le recrutement de coactivateurs qui augmente encore plus la taille des complexes afin d'acquérir un potentiel d'activation maximal. En utilisant ces approches moléculaires, nous avons pu caractériser les mécanismes permettant aux phtalates, une classe de polluants provenant de l'industrie plastique, d'interférer avec PPARγ. La liaison du mono-ethyl-hexyl-phtalate (NERF) à PPARγ induit un recrutement sélectif de cofacteurs, se traduisant par l'induction spécifique d'un sous-ensemble de gènes qui varie en fonction du niveau de différentiation cellulaire. La modulation sélective de PPARγ par le MEHP provoque une adipogenèse modérée dans des modèles cellulaires alors que l'exposition de modèles animaux aux phtalates induit des effets bénéfiques sur la tolérance au glucose et sur le développement de l'obésité. Toutefois, les phtalates ont une action complexe sur le métabolisme glucido-lipidique en faisant intervenir PPARγ mais aussi probablement PPARα et PPARß. Cette démonstration moléculaire et physiologique de l'interférence des polluants avec les récepteurs nucléaires PPAR souligne un rôle important de l'exposition à de tels composés dans les régulations métaboliques.

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The disintegration of the USSR brought the emergence of a new geo-energy space in Central Asia. This space arose in the context of a global energy transition, which began in the late 1970s. Therefore, this new space in a changing energy world requires both new conceptual frameworks of analysis and the creation of new analytical tools. Taking into account this fact, our paper attempts to apply the theoretical framework of the Global Commodity Chain (GCC) to the case of natural resources in Central Asia. The aim of the paper is to check if there could be any Central Asia’s geo-energy space, assuming that this space would exist if natural resources were managed with regional criteria. The paper is divided into four sections. First an introduction that describes the new global energy context within natural resources of Central Asia would be integrated. Secondly, the paper justifies why the GCC methodology is suitable for the study of the value chains of energy products. Thirdly, we build up three cases studies (oil and uranium from Kazakhstan and gas from Turkmenistan) which reveal a high degree of uncertainty over the direction these chains will take. Finally, we present the conclusions of this study that state that the most plausible scenario would be the integration of energy resources of these countries in GCC where the core of the decision-making process will be far away from the region of Central Asia. Key words: Energy transition, geo-energy space, Global Commodity Chains, Central Asia

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In this study we evaluate the dynamics of the biophile element phosphorus (P) in the catchment and proglacial areas of the Rhone and Oberaar glaciers (central Switzerland). We analysed erosion and dissolution rates of P-containing minerals in the subglacial environment by sampling water and suspended sediment in glacier outlets during three ablation and two accumulation seasons. We also quantified biogeochemical weathering rates of detrital P in proglacial sedimentary deposits using two chronosequences of samples of fresh, suspended, material obtained from the Oberaar and Rhone water outlets, Little-Ice-Age (LIA) moraines and Younger Dryas (YD) tills in each catchment. Subglacial P weathering is mainly a physical process and detrital P represents more than 99%, of the precipitation-corrected total P denudation flux (234 and 540 kg km(-2) yr(-1) for the Rhone and Oberaar catchments, respectively). The calculated detrital P flux rates are three to almost five times higher than the world average flux. The precipitation-corrected soluble reactive P (SRP) flux corresponds to 1.88-1.99 kg km(-2) yr(-1) (Rhone) and 2.12-2.44 kg km(-2) yr(-1) (Oberaar), respectively. These fluxes are comparable to those of tropical rivers draining transport-limited, tectonically inactive weathering areas. In order to evaluate the efficiency of detrital P weathering in the Rhone and Oberaar proglacial areas, we systematically graded apatite grains extracted from the chronosequence in each catchment relative to weathering-induced changes in their surface morphologies (grades 1-4). Fresh apatite grains are heavily indented and dissolution rounded (grade 1). LIA grains from two 0-10 cm deep moraine samples show extensive dissolution etching, similar to surface grains from the YD profile (mean grades 2.7, 3.5 and 3.5, respectively). In these proglacial deposits, the weathering front deepens progressively as a function of time due to biocorrosion in the evolving acidic pedosphere, with mechanical indentations on grains acting as sites of preferential dissolution. We also measured iron-bound, organic and detrital P concentrations in the chronosequence and show that organic and iron-bound P has almost completely replaced detrital P in the top layers of the YD profiles. Detrital P weathering rates are calculated as 3 10 and 280 kg km(-2) yr(-1) for LIA moraines and 10 kg km(-2) yr(-1) for YD tills. During the first 300 years of glacial sediment exposure P dissolution rates are shown to be approximately 70 times higher than the mean global dissolved P flux from ice-free continents. After 11.6 kyr the flux is 2.5 times the global mean. These data strengthen the argument for substantial changes in the global dissolved P flux on glacial-interglacial timescales. A crude extrapolation from the data described here suggests that the global dissolved P flux may increase by 40-45% during the first few hundred years of a deglaciation phase

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Ryanodine receptor 1 (RYR1) mutations are a common cause of congenital myopathies associated with both dominant and recessive inheritance. Histopathological findings frequently feature central cores or multi-minicores, more rarely, type 1 predominance/uniformity, fiber-type disproportion, increased internal nucleation, and fatty and connective tissue. We describe 71 families, 35 associated with dominant RYR1 mutations and 36 with recessive inheritance. Five of the dominant mutations and 35 of the 55 recessive mutations have not been previously reported. Dominant mutations, typically missense, were frequently located in recognized mutational hotspot regions, while recessive mutations were distributed throughout the entire coding sequence. Recessive mutations included nonsense and splice mutations expected to result in reduced RyR1 protein. There was wide clinical variability. As a group, dominant mutations were associated with milder phenotypes; patients with recessive inheritance had earlier onset, more weakness, and functional limitations. Extraocular and bulbar muscle involvement was almost exclusively observed in the recessive group. In conclusion, our study reports a large number of novel RYR1 mutations and indicates that recessive variants are at least as frequent as the dominant ones. Assigning pathogenicity to novel mutations is often difficult, and interpretation of genetic results in the context of clinical, histological, and muscle magnetic resonance imaging findings is essential.

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This study aimed to estimate the frequency, associated factors, and molecular characterisation of Entamoeba histolytica, Entamoeba dispar, Entamoeba moshkovskii, andEntamoeba hartmanni infections. We performed a survey (n = 213 subjects) to obtain parasitological, sanitation, and sociodemographic data. Faecal samples were processed through flotation and centrifugation methods.E. histolytica, E. dispar, E. moshkovskii, and E. hartmanni were identified by nested-polymerase chain reaction (PCR). The overall prevalence of infection was 22/213 (10.3%). The infection rate among subjects who drink rainwater collected from roofs in tanks was higher than the rate in subjects who drink desalinated water pumped from wells; similarly, the infection rate among subjects who practice open defecation was significantly higher than that of subjects with latrines. Out of the 22 samples positive for morphologically indistinguishableEntamoeba species, the differentiation by PCR was successful for 21. The species distribution was as follows: 57.1% to E. dispar, 23.8% to E. histolytica, 14.3% toE. histolytica and E. dispar, and 4.8% E. dispar and E. hartmanni. These data suggest a high prevalence of asymptomatic infection by the group of morphologically indistinguishable Entamoeba histolytica/dispar/moshkovskiicomplex and E. hartmanni species. In this context of water scarcity, the sanitary and socioenvironmental characteristics of the region appear to favour transmission.

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Emotions are crucial for user's decision making in recommendation processes. We first introduce ambient recommender systems, which arise from the analysis of new trends on the exploitation of the emotional context in the next generation of recommender systems. We then explain some results of these new trends in real-world applications through the smart prediction assistant (SPA) platform in an intelligent learning guide with more than three million users. While most approaches to recommending have focused on algorithm performance. SPA makes recommendations to users on the basis of emotional information acquired in an incremental way. This article provides a cross-disciplinary perspective to achieve this goal in such recommender systems through a SPA platform. The methodology applied in SPA is the result of a bunch of technology transfer projects for large real-world rccommender systems

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This paper presents the distributed environment for virtual and/or real experiments for underwater robots (DEVRE). This environment is composed of a set of processes running on a local area network composed of three sites: 1) the onboard AUV computer; 2) a surface computer used as human-machine interface (HMI); and 3) a computer used for simulating the vehicle dynamics and representing the virtual world. The HMI can be transparently linked to the real sensors and actuators dealing with a real mission. It can also be linked with virtual sensors and virtual actuators, dealing with a virtual mission. The aim of DEVRE is to assist engineers during the software development and testing in the lab prior to real experiments

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Durant les últimes dècades, en un context en què impera la influència de les TIC, el model de l'ensenyament universitari ha canviat radicalment. Paral·lelament, els rols de l'estudiant i del professor també s'han vist modificats: l'estudiant ha deixat de ser un lector passiu per convertir-se en un lector que participa activament en el procés d'aprenentatge, aportant material complementari i en diferents suports a la informació que li arriba. Neix, així, el concepte de lectura augmentada. La Universitat Oberta de Catalunya és un exemple de la tendència de futur de l'ensenyament universitari, en què l'estudiant pren les regnes de l'aprenentatge i les institucions educatives s'adapten a les noves necessitats de l'usuari afavorint la flexibilitat, la mobilitat i les eines tecnològiques imprescindibles per a aquest nou model d'ensenyament.

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La Universitat Oberta de Catalunya (UOC) és un exemple de la tendència de futur de l'ensenyament universitari, en què l'estudiant pren les regnes de l'aprenenetatge i les institucions educatives s'adapten a les noves necessitats de l'usuari afavorint la flexibilitat, la mobilitat i les eines tecnològiques imprescindibles per a aquest nou model d'enseyament.

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Spatial variation in the pattern of natural selection can promote local adaptation and genetic differentiation between populations. Because heritable melanin-based ornaments can signal resistance to environmentally mediated elevation in glucocorticoids, to oxidative stress and parasites, populations may vary in the mean degree of melanic coloration if selection on these phenotypic aspects varies geographically. Within a population of Swiss barn owls (Tyto alba), the size of eumelanic spots is positively associated with survival, immunity and resistance to stress, but it is yet unknown whether Tyto species that face stressful environments evolved towards a darker eumelanic plumage. Because selection regimes vary along environmental gradients, we examined whether melanin-based traits vary clinally and are expressed to a larger extent in the tropics where parasites are more abundant than in temperate zones. To this end, we considered 39 barn owl species distributed worldwide. Barn owl species living in the tropics displayed larger eumelanic spots than those found in temperate zones. This was, however, verified in the northern hemisphere only. Parasites being particularly abundant in the tropics, they may promote the evolution of darker eumelanic ornaments.