117 research outputs found

    Query Migration from Object Oriented World to Semantic World

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    — In the last decades, object-oriented approach was able to take a large share of databases market aiming to design and implement structured and reusable software through the composition of independent elements in order to have programs with a high performance. On the other hand, the mass of information stored in the web is increasing day after day with a vertiginous speed, exposing the currently web faced with the problem of creating a bridge so as to facilitate access to data between different applications and systems as well as to look for relevant and exact information wished by users. In addition, all existing approach of rewriting object oriented languages to SPARQL language rely on models transformation process to guarantee this mapping. All the previous raisons has prompted us to write this paper in order to bridge an important gap between these two heterogeneous worlds (object oriented and semantic web world) by proposing the first provably semantics preserving OQLto-SPARQL translation algorithm for each element of OQL Query (SELECT clause, FROM clause, FILTER constraint, implicit/ explicit join and union/intersection SELECT queries)

    Conception et rĂ©alisation d’un systĂšme d’information pour le calcul d’itinĂ©raires destinĂ© aux services d’urgence

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    The present-day issue of looking for the most appropriate route is widely studied for various applications such as cycling or pedestrians, the interception of a mobile object, multimodal or combining means of transport.With this approach, our objective is to search for the best itinerary for emergency vehicles. Our study has been carried out in partnership with the SMUR (emergency medical assistance) in Le Mans, which has provided an operational context.Our research work firstly dealt with the records of the routes used by emergency vehicles so as to obtain a more accurate estimation of journey times. For this task, our methodology begins with a phase of modelising mobile objects using statistical analysis and data mining to reach phases of implementation and validation. During the modelisation phase, we propose the use of an approach that creates a link between modeling and management of mobile objects by Abstract Data Types (TAD) and conceptual modeling based on MADS. So as to improve estimation of journey time a method of Multiple Correspondence Analysis and a technique for creating trees and decision rules were used. For the validation process of journey time, we compared routes suggested by a research algorithm application for the shortest trip and the routes used by the emergency services.Secondly, so as to take into consideration time value and the uncertainty of journey time estimations due to disturbances, the mode depending on time with graph per interval and the notion of degree of optimism will be retained for the implementation of our calculator. We propose two versions of itinerary research: a single unique fastest route and the first k optimal routes. So as to minimize the risk of blocking, a second version is of benefit in the case of two emergency units leaving for the same intervention. Each will use a different route to maximize the chances of arriving on the scene quickly Intervention.The ultimate stage involved considering in real time the consequences of exceptional foreseen events (demonstrations, roadworks), changes in the physical characteristics of the road network, weather conditions and those that could not be predicted (traffic congestion and accidents) that can influence the choice of a route, for which we propose a system to help in the management of such a disturbance in real time.De nos jours, la problĂ©matique de recherche du meilleur itinĂ©raire est trĂšs Ă©tudiĂ©e dans diverses applications telles que pour le mode de transport doux (vĂ©lo) ou piĂ©tonnier, pour l’interception d’un objet mobile ou encore pour la combinaison des modes de transport (multimodal). Dans cette optique, notre objectif consiste Ă  chercher un meilleur itinĂ©raire pour les services d’urgence. Notre Ă©tude est rĂ©alisĂ©e en partenariat avec le SMUR du Mans (Sarthe) qui fournit le contexte opĂ©rationnel. Dans un premier temps, ce travail de recherche consiste Ă  exploiter l’historique des trajectoires empruntĂ©es par le service d’urgence pour avoir une meilleure estimation du temps de parcours. Afin de rĂ©aliser cette tĂąche, nous proposons une mĂ©thodologie partant de la phase de la modĂ©lisation des objets mobiles passant par une Ă©tape d’analyse statistique et de data mining et allant jusqu'aux phases de l’implĂ©mentation et de la validation. Concernant la phase de la modĂ©lisation, nous proposons une approche qui fait le lien entre une modĂ©lisation et une gestion des objets mobiles par des Types Abstraits de DonnĂ©es (TAD) et une modĂ©lisation conceptuelle basĂ©e sur MADS. En vue d’avoir une meilleure estimation du temps de parcours, une mĂ©thode d’Analyse des Correspondances Multiples et une technique de crĂ©ation d’arbres et de rĂšgles de dĂ©cision sont utilisĂ©es. Pour le processus de la validation de notre mĂ©thode d’estimation du temps de parcours, nous procĂ©dons par une comparaison entre les itinĂ©raires proposĂ©s par application d’un algorithme de recherche du plus court chemin et les trajectoires empruntĂ©es par le service d’urgence. Dans un deuxiĂšme temps, et pour pouvoir prendre en considĂ©ration la temporalitĂ© et l’incertitude sur les estimations du temps de parcours causĂ©es par les diffĂ©rents types de perturbations, le mode dĂ©pendant du temps avec graphe par intervalle et la notion de degrĂ© d’optimisme seront retenus pour l’implĂ©mentation de notre calculateur. On propose deux versions de recherche d’itinĂ©raires : un seul et unique chemin le plus rapide et les k premiers chemins optimaux. Afin de minimiser le risque de blocage, la deuxiĂšme version sera bĂ©nĂ©fique dans le cas oĂč deux Ă©quipes partent pour une mĂȘme intervention. Chacune d’entre elles empruntera un chemin diffĂ©rent afin d'optimiser les chances d'arriver rapidement sur les lieux d'intervention.Enfin, et pour prendre en considĂ©ration en temps rĂ©el les Ă©vĂ©nements exceptionnels prĂ©vus (manifestations, travaux publics), les changements des caractĂ©ristiques physiques du rĂ©seau routier, les conditions mĂ©tĂ©orologiques et les Ă©vĂ©nements imprĂ©vus (embouteillages, accidents) qui peuvent influer sur le choix d’itinĂ©raires, nous proposons un systĂšme d’aide Ă  la prise en compte des perturbations du trafic en temps rĂ©el

    Neurons Expressing Pathological Tau Protein Trigger Dramatic Changes in Microglial Morphology and Dynamics

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    International audienceMicroglial cells, the resident macrophages of the brain, are important players in the pathological process of numerous neurodegenerative disorders, including tauopathies, a heterogeneous class of diseases characterized by intraneuronal Tau aggregates. However, microglia response in Tau pathologies remains poorly understood. Here, we exploit a genetic zebrafish model of tauopathy, combined with live microglia imaging, to investigate the behavior of microglia in vivo in the disease context. Results show that while microglia were almost immobile and displayed long and highly dynamic branches in a wild-type context, in presence of diseased neurons, cells became highly mobile and displayed morphological changes, with highly mobile cell bodies together with fewer and shorter processes. We also imaged, for the first time to our knowledge, the phagocytosis of apoptotic tauopathic neurons by microglia in vivo and observed that microglia engulfed about as twice materials as in controls. Finally, genetic ablation of microglia in zebrafish tauopathy model significantly increased Tau hyperphosphorylation, suggesting that microglia provide neuroprotection to diseased neurons. Our findings demonstrate for the first time the dynamics of microglia in contact with tauopathic neurons in vivo and open perspectives for the real-time study of microglia in many neuronal diseases

    Altered vaccine-induced immunity in children with Dravet syndrome

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    International audienceDravet syndrome (DS) is a refractory epileptic syndrome. Vaccination is the trigger of the first seizure in about 50% of cases. Fever remains a trigger of seizures during the course of the disease. We compared ex vivo cytokine responses to a combined aluminium-adjuvanted vaccine of children with DS to sex-and age-matched heathy children. Using ex vivo cytokine responses of peripheral-blood mononuclear cells and monocytes, we found that vaccine responsiveness is biased toward a proinflammatory profile in DS with a M1 phenotype of monocytes. We provide new insight into immune mechanisms associated with DS that might guide research for the development of new immunotherapeutic agents in this epilepsy syndrome

    Methanation of carbon dioxide over ceria-praseodymia promoted Ni-alumina catalysts. Influence of metal loading, promoter composition and alumina modifier

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    [EN] Two series of ceria-praseodymia promoted Ni-alumina catalysts were prepared from two different commercial modified alumina supports (3.5 wt% SiO2-Al2O3 and 4.0 wt% La2O3-Al2O3) by the incipient wetness impregnation method in two successive steps. The resulting materials were characterized in terms of their physicochemical properties by means of N2 physical adsorption at −196 °C, powder X-ray diffraction (XRD) and temperature programmed reduction with H2 (H2-TPR). Furthermore, the as-prepared catalysts were tested for the CO2 methanation reaction in a fixed-bed reactor at atmospheric pressure, gas hourly space velocity (GHSV) of 72,000 cm3·(h·gcat)−1 and CO2/H2 molar ratio of 1/4 over the temperature range from 25 up to 850 °C. The influence of the nominal Ni loading (3, 5 and 10 wt%), molar composition of the Ce/Pr mixed oxide promoter (80/20 and 60/40), and alumina modifier (silica and lanthana) on the catalytic performance was carefully analyzed. Among these three composition parameters, the alumina dopant and especially the Ni content appear to have by far a much more pronounced effect on both the CO2 conversion and CH4 selectivity as compared to the Ce/Pr mixed oxide composition. Specifically, from the catalytic tests the sample containing a 10 wt% Ni loading, a Ce/Pr mixed oxide promoter of 80/20 molar composition, and silica as modifier provides the highest catalytic activity in terms of CO2 conversion and CH4 selectivity. Such behaviour has been ascribed to a complex interplay between several factors, mainly the larger fraction of catalytically active ÎČ-type NiO specie

    Palladium-Catalyzed Coupling of 3-Halo-Substituted Coumarins, Chromenes, and Quinolones with Various Nitrogen-Containing Nucleophiles

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    International audienceAn efficient and general palladium‐catalyzed coupling reaction between 3‐bromocoumarins, 3‐bromoquinolin‐2(1H)‐ones, and 3‐iodo‐2H‐chromenes with a variety of nitrogen‐containing nucleophiles (azole, amide, lactam, sulfonamide, aniline, amine, and urea) is described. The reaction proceeded rapidly and cleanly in dioxane providing the coupling products in good to excellent yields. The chemoselectivity of this reaction was also studied with polyhalocoumarins. Under optimized conditions, these underwent a site‐selective amination at the C‐3–Br bond, regardless of the nature of the nitrogen‐containing nucleophile used

    Comprehensive Review on Climate Control and Cooling Systems in Greenhouses under Hot and Arid Conditions

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    This work is motivated by the difficulty of cultivating crops in horticulture greenhouses under hot and arid climate conditions. The main challenge is to provide a suitable greenhouse indoor environment, with sufficiently low costs and low environmental impacts. The climate control inside the greenhouse constitutes an efficient methodology for maintaining a satisfactory environment that fulfills the requirements of high-yield crops and reduced energy and water resource consumption. In hot climates, the cooling systems, which are assisted by an effective control technique, constitute a suitable path for maintaining an appropriate climate inside the greenhouse, where the required temperature and humidity distribution is maintained. Nevertheless, most of the commonly used systems are either highly energy or water consuming. Hence, the main objective of this work is to provide a detailed review of the research studies that have been carried out during the last few years, with a specific focus on the technologies that allow for the enhancement of the system effectiveness under hot and arid conditions, and that decrease the energy and water consumption. Climate control processes in the greenhouse by means of manual and smart control systems are investigated first. Subsequently, the different cooling technologies that provide the required ranges of temperature and humidity inside the greenhouse are detailed, namely, the systems using heat exchangers, ventilation, evaporation, and desiccants. Finally, the recommended energy-efficient approaches of the desiccant dehumidification systems for greenhouse farming are pointed out, and the future trends in cooling systems, which include water recovery using the method of combined evaporation–condensation, as well as the opportunities for further research and development, are identified as a contribution to future research work.EC/H2020/101000801/EU/Thermochemical fluids in greenhouse farming/TheGreef
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