932 resultados para Social event detection


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Chez les mammifères, les phéromones sont des molécules clés dans la régulation des comportements sociaux au sein d'une espèce. Chez la souris, la détection de ces molécules se fait dans l'organe voméronasal (VNO] et implique le canal TRPC2 afin de dépolariser les neurones. Des différences de comportement entre des souris Trpc2-/- et des souris sans VNO suggèrent l'implication d'une autre protéine effectrice dans la voie de signalisation des phéromones. L'hypothèse étant que cette protéine formerait un canal hétéromérique avec TRPC2. CNGA4 est une protéine sans fonction connue dans le VNO des rongeurs. Elle appartient à la famille des protéines CNG qui joue un rôle important dans différentes voies de signalisation comme la vision ou l'olfaction. Etant donné sa présence dans le VNO, son rôle inconnu dans cet organe et son rôle important dans de nombreuses voies de signalisation, nous avons décidé d'étudier CNGA4 afin de connaître sa localisation, ses propriétés ou encore sa structure. Nous avons découvert que CNGA4 est exprimée dans les axons, les neurones immatures ainsi que sur les microvillosités des neurones de VNO. A l'aide de souris portant une version non fonctionnelle de CNGA4, nous avons pu montrer que cette protéine joue un rôle majeur dans la voie de signalisation des phéromones. Ainsi, les neurones du VNO portant une version non fonctionnelle de CNGA4 répondent moins fréquemment aux phéromones et par conséquent les phéromones activent également moins de neurones dans le bulbe olfactif accessoire, premier relais du VNO avec le cortex. Cette détection défaillante se traduit par une absence d'agressivité des souris mutantes ainsi que par une incapacité de ces souris à discriminer le sexe de leur conspécifique. Etant donné les propriétés similaires de CNGA4 et de TRPC2, nous avons supposé que les deux protéines pourraient interagir. Cette hypothèse a été confortée par l'observation que CNGA4 n'est plus exprimée dans les microvillosités du VNO des souris Trpc2-/-. A l'aide d'expériences d'expression hétérologue, nous avons pu observer que les deux protéines interagissent et forment un canal activé par un analogue du diacylglycérol suggérant que ce canal est fonctionnel. Ces résultats indiquent que CNGA4 formerait un canal hétéromérique avec TRPC2 et aurait dans ce canal une fonction modulatrice. Des expériences complémentaires sont nécessaires afin de connaître le rôle de chacune de ces protéines dans la voie de signalisation des phéromones. Sensing pheromones: a role for the CNGA4 and TRPC2 proteins Mammalian pheromones are key chemical signals in the regulation of intraspecies social behaviors. Detection of these pheromones, which takes place in sensory neurons of the vomeronasal organ (VNO), implies the activation of the transient receptor potential canonical channel 2 (TRPC2) as the final effector. Interestingly, discrepancies between Trpc2 /- mice and mice lacking a VNO suggest the implication of another protein in the pheromone signaling pathway. This protein could either form a heteromeric channel with TRPC2 or a separate homomeric ion channel. The cyclic nucleotide-gated channel subunit CNGA4 is also expressed in the rodent VNO but its role and properties in this organ remain unknown. CNGA4 belongs to the CNG channel family which is playing an important role in different sensory pathways such as in light and odorant detection. We thus decided to study the role of the CNGA4 protein in the mouse VNO. We found CNGA4 to be expressed in axons, dendrites and in the sensory microvilli. Using mice bearing a non-functional form of CNGA4 we further demonstrated the importance of the CNGA4 protein for the pheromone signaling pathway as neurons from mutant mice were responding less frequently to chemosensory cues. As a result, mutant mice displayed a non-aggressive behavior and an impaired sexual discrimination ability. Based on the CNGA4 localization and its role in the pheromone signaling pathway we hypothesized a possible interaction between CNGA4 and TRPC2 forming a heteromeric channel. First evidences for this interaction came from the absence of CNGA4 expression in the sensory microvilli of Trpc2-/- mice. Second, using transfected HEK cells as an expression system we could observe that CNGA4 and TRPC2 interact and translocate to the plasma membrane. Perfusion of a DAG analogue on co-transfected HEK cells resulted in a strong calcium entry suggesting that the two proteins form a functional channel. These results might suggest a modulatory role for CNGA4 in a heteromeric TRPC2+CNGA4 ion channel. Further experiments will give more insights on the combined role of these transduction ion channels in pheromone detection.

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The high sensitivity and excellent timing accuracy of Geiger mode avalanche photodiodes makes them ideal sensors as pixel detectors for particle tracking in high energy physics experiments to be performed in future linear colliders. Nevertheless, it is well known that these sensors suffer from dark counts and afterpulsing noise, which induce false hits (indistinguishable from event detection) as well as an increase of the necessary area of the readout system. In this work, we present a comparison between APDs fabricated in a high voltage 0.35 µm and a high integration 0.13 µm commercially available CMOS technologies that has been performed to determine which of them best fits the particle collider requirements. In addition, a readout circuit that allows low noise operation is introduced. Experimental characterization of the proposed pixel is also presented in this work.

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In 1903, the Canadian Association of Amateur Oarsmen had their request granted to make the Old Welland Canal at Port Dalhousie the permanent site of the Royal Canadian Henley Regatta. That same year organized rowing was established in St. Catharines when the St. Catharines Rowing and Canoe Club was formed. The Henley course was completed in July of 1903 after rowing was well underway. Although the Henley course served as an athletic and social event, rowing itself was slow to grow in the St. Catharines area. In 1915 the Regatta was cancelled for the duration of WWI and reinstated in 1919 when an increased public interest in the sport began to grow. Two years later, the Henley Aquatic Association was formed in order to control, maintain and improve the rowing facilities. This association was responsible for building a new clubhouse at Ann Street in 1921 and in 1931 completing the grandstands. Also in the 1930s the association had the Federal Government approve their appeal to have the Henley waters dredged for the first time. The St. Catharines Rowing Club re-located its headquarters to the Lakeport Road site. The 1940s brought more support from local groups and with that more events. In 1945, the St. Catharines Junior Chamber of Commerce began helping to organize and promote rowing locally. One of the new events at the Henley course was the "Schoolboy Championships". The growth of both rowing and the Henley continued growing through the 1950s. The Henley Aquatic Association acquired Reid's Island, now Henley Island, mainly through the efforts of Ted Nelson. In the 1960s, rowing really took off in St. Catharines. Women began to become recognized in the sport when Brock University created a women's rowing team. The second dredging was completed in 1964, leading to the creation of a world class rowing course. The facilities were upgraded to international standards and the Henley rowing course became Canada's first Class A FISA (Fédération Internationale des Sociétés d’Aviron or International Federation of Rowing Associations) rowing course. The first North American Rowing Championship was held at the Henley course in 1967 and again in 1970 for the third championship. The Canadian Henley Rowing Corporation formed in 1972, along with the St. Catharines, Parks and Recreation Department created the first rowing school for youth. Since 1960, St. Catharines has been at a competitive level with other International rowing courses. The city continues to produce Olympic level athletes today.

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La maladie cœliaque ou sprue cœliaque est une intolérance au gluten. Il s’agit d’une maladie inflammatoire de l’intestin liée à l’ingestion de gluten chez des personnes génétiquement susceptibles. Ce désordre présente une forte prévalence puisqu’il touche 1 % de la population mondiale. En l’état actuel des choses, il n’existe aucun outil pharmacologique pour traiter ou pallier à cette maladie. Cependant, grâce aux avancées dans la compréhension de sa pathogenèse, de nouvelles cibles thérapeutiques ont été identifiées. À l’heure actuelle, le seul traitement efficace consiste à suspendre la consommation de l’agent pathogène, à savoir le gluten. Le gluten est un ensemble de protéines de stockage des céréales contenu dans le blé, l’orge et le seigle. Le gluten du blé se subdivise en gluténines et gliadines. Ce sont ces dernières qui semblent les plus impliquées dans la maladie cœliaque. Les gliadines et ses protéines apparentées (i.e. sécalines et hordéines, respectivement dans le seigle et l’orge) sont riches en prolines et en glutamines, les rendant résistantes à la dégradation par les enzymes digestives et celles de la bordure en brosse. Les peptides résultant de cette digestion incomplète peuvent induire des réponses immunitaires acquises et innées. L’objectif principal de cette thèse était de tester un nouveau traitement d’appoint de la maladie cœliaque utile lors de voyages ou d’évènements ponctuels. Dans les années 80, une observation italienne montra l’inhibition de certains effets induits par des gliadines digérées sur des cultures cellulaires grâce à la co-incubation en présence de mannane: un polyoside naturel composé de mannoses. Malheureusement, ce traitement n’était pas applicable in vivo à cause de la dégradation par les enzymes du tractus gastro-intestinales du polymère, de par sa nature osidique. Les polymères de synthèse, grâce à la diversité et au contrôle de leurs propriétés physico-chimiques, se révèlent être une alternative attrayante à ce polymère naturel. L’objectif de cette recherche était d’obtenir un polymère liant la gliadine, capable d’interférer dans la genèse de la maladie au niveau du tube digestif, afin d’abolir les effets délétères induits par la protéine. Tout d’abord, des copolymères de type poly (hydroxyéthylméthacrylate)-co-(styrène sulfonate) (P(HEMA-co-SS)) ont été synthétisés par polymérisation radicalaire contrôlée par transfert d’atome (ATRP). Une petite bibliothèque de polymères a été préparée en faisant varier la masse molaire, ainsi que les proportions de chacun des monomères. Ces polymères ont ensuite été testés quant à leur capacité de complexer la gliadine aux pH stomacal et intestinal et les meilleurs candidats ont été retenus pour des essais cellulaires. Les travaux ont permis de montrer que le copolymère P(HEMA-co-SS) (45:55 mol%, 40 kDa) permettait une séquestration sélective de la gliadine et qu’il abolissait les effets induits par la gliadine sur différents types cellulaires. De plus, ce composé interférait avec la digestion de la gliadine, suggérant une diminution de peptides immunogènes impliqués dans la maladie. Ce candidat a été testé in vivo, sur un modèle murin sensible au gluten, quant à son efficacité vis-à-vis de la gliadine pure et d’un mélange contenant du gluten avec d’autres composants alimentaires. Le P(HEMA-co-SS) a permis de diminuer les effets sur les paramètres de perméabilité et d’inflammation, ainsi que de moduler la réponse immunitaire engendrée par l’administration de gliadine et celle du gluten. Des études de toxicité et de biodistribution en administration aigüe et chronique ont été réalisées afin de démontrer que ce dernier était bien toléré et peu absorbé suite à son administration par la voie orale. Enfin des études sur des échantillons de tissus de patients souffrants de maladie cœliaque ont montré un bénéfice therapeutique du polymère. L’ensemble des travaux présentés dans cette thèse a permis de mettre en évidence le potentiel thérapeutique du P(HEMA-co-SS) pour prévenir les désordres reliés à l’ingestion de gluten, indiquant que ce type de polymère pourrait être exploité dans un avenir proche.

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Two vertical cosmic ray telescopes for atmospheric cosmic ray ionization event detection are compared. Counter A, designed for low power remote use, was deployed in the Welsh mountains; its event rate increased with altitude as expected from atmospheric cosmic ray absorption. Independently, Counter B’s event rate was found to vary with incoming particle acceptance angle. Simultaneous colocated comparison of both telescopes exposed to atmospheric ionization showed a linear relationship between their event rates.

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This paper presents the two datasets (ARENA and P5) and the challenge that form a part of the PETS 2015 workshop. The datasets consist of scenarios recorded by us- ing multiple visual and thermal sensors. The scenarios in ARENA dataset involve different staged activities around a parked vehicle in a parking lot in UK and those in P5 dataset involve different staged activities around the perimeter of a nuclear power plant in Sweden. The scenarios of each dataset are grouped into ‘Normal’, ‘Warning’ and ‘Alarm’ categories. The Challenge specifically includes tasks that account for different steps in a video understanding system: Low-Level Video Analysis (object detection and tracking), Mid-Level Video Analysis (‘atomic’ event detection) and High-Level Video Analysis (‘complex’ event detection). The evaluation methodology used for the Challenge includes well-established measures.

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This paper describes the dataset and vision challenges that form part of the PETS 2014 workshop. The datasets are multisensor sequences containing different activities around a parked vehicle in a parking lot. The dataset scenarios were filmed from multiple cameras mounted on the vehicle itself and involve multiple actors. In PETS2014 workshop, 22 acted scenarios are provided of abnormal behaviour around the parked vehicle. The aim in PETS 2014 is to provide a standard benchmark that indicates how detection, tracking, abnormality and behaviour analysis systems perform against a common database. The dataset specifically addresses several vision challenges corresponding to different steps in a video understanding system: Low-Level Video Analysis (object detection and tracking), Mid-Level Video Analysis (‘simple’ event detection: the behaviour recognition of a single actor) and High-Level Video Analysis (‘complex’ event detection: the behaviour and interaction recognition of several actors).

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Synoptic wind events in the equatorial Pacific strongly influence the El Niño/Southern Oscillation (ENSO) evolution. This paper characterizes the spatio-temporal distribution of Easterly (EWEs) and Westerly Wind Events (WWEs) and quantifies their relationship with intraseasonal and interannual large-scale climate variability. We unambiguously demonstrate that the Madden–Julian Oscillation (MJO) and Convectively-coupled Rossby Waves (CRW) modulate both WWEs and EWEs occurrence probability. 86 % of WWEs occur within convective MJO and/or CRW phases and 83 % of EWEs occur within the suppressed phase of MJO and/or CRW. 41 % of WWEs and 26 % of EWEs are in particular associated with the combined occurrence of a CRW/MJO, far more than what would be expected from a random distribution (3 %). Wind events embedded within MJO phases also have a stronger impact on the ocean, due to a tendency to have a larger amplitude, zonal extent and longer duration. These findings are robust irrespective of the wind events and MJO/CRW detection methods. While WWEs and EWEs behave rather symmetrically with respect to MJO/CRW activity, the impact of ENSO on wind events is asymmetrical. The WWEs occurrence probability indeed increases when the warm pool is displaced eastward during El Niño events, an increase that can partly be related to interannual modulation of the MJO/CRW activity in the western Pacific. On the other hand, the EWEs modulation by ENSO is less robust, and strongly depends on the wind event detection method. The consequences of these results for ENSO predictability are discussed.

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A política de indexação deve ser constituída de estratégias que permitam o alcance dos objetivos de recuperação do sistema de informação. O indexador tem a função primordial de compreender o documento ao realizar uma análise conceitual que represente adequadamente seu conteúdo. Utilizando a leitura como evento social/protocolo verbal em grupo, nosso objetivo é contribuir com a literatura sobre política de indexação e apresentar propostas de ensino de política de indexação direcionadas a alunos de graduação e pós-graduação, além de uma experiência de educação à distância com vistas à formação do bibliotecário em serviço. Os resultados obtidos demonstraram que a metodologia pode ser utilizada por sistemas de informação para que se tenha acesso ao conhecimento do indexador. Conclui que o indexador deve ser o alvo de investimento dos sistemas de informação e sugere aos sistemas de informação que a experiência do indexador também seja utilizada como parâmetro para política de indexação.

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Pós-graduação em Ciência da Computação - IBILCE

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Public organizations today ar constantly developing relationship strategies with audiences in search of acceptance before the public. The objective of this wor is to present strategies of Governmental Public Relations and Political Marketing that can be implemented by communication professionals in government. Therefore, duscysses principles and instruments of the objects mentioned, conducting study on actions taken by the Municipality of Botucatu city during the anniversary year of 2012, with na emphasis on the social event, Food Court Solidarity. The instruments studied contribute to the strengthening of relations between government and citizens, while complying with its commitments under its plan, meeting the demands of the population

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This book will serve as a foundation for a variety of useful applications of graph theory to computer vision, pattern recognition, and related areas. It covers a representative set of novel graph-theoretic methods for complex computer vision and pattern recognition tasks. The first part of the book presents the application of graph theory to low-level processing of digital images such as a new method for partitioning a given image into a hierarchy of homogeneous areas using graph pyramids, or a study of the relationship between graph theory and digital topology. Part II presents graph-theoretic learning algorithms for high-level computer vision and pattern recognition applications, including a survey of graph based methodologies for pattern recognition and computer vision, a presentation of a series of computationally efficient algorithms for testing graph isomorphism and related graph matching tasks in pattern recognition and a new graph distance measure to be used for solving graph matching problems. Finally, Part III provides detailed descriptions of several applications of graph-based methods to real-world pattern recognition tasks. It includes a critical review of the main graph-based and structural methods for fingerprint classification, a new method to visualize time series of graphs, and potential applications in computer network monitoring and abnormal event detection.

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Various applications for the purposes of event detection, localization, and monitoring can benefit from the use of wireless sensor networks (WSNs). Wireless sensor networks are generally easy to deploy, with flexible topology and can support diversity of tasks thanks to the large variety of sensors that can be attached to the wireless sensor nodes. To guarantee the efficient operation of such a heterogeneous wireless sensor networks during its lifetime an appropriate management is necessary. Typically, there are three management tasks, namely monitoring, (re) configuration, and code updating. On the one hand, status information, such as battery state and node connectivity, of both the wireless sensor network and the sensor nodes has to be monitored. And on the other hand, sensor nodes have to be (re)configured, e.g., setting the sensing interval. Most importantly, new applications have to be deployed as well as bug fixes have to be applied during the network lifetime. All management tasks have to be performed in a reliable, time- and energy-efficient manner. The ability to disseminate data from one sender to multiple receivers in a reliable, time- and energy-efficient manner is critical for the execution of the management tasks, especially for code updating. Using multicast communication in wireless sensor networks is an efficient way to handle such traffic pattern. Due to the nature of code updates a multicast protocol has to support bulky traffic and endto-end reliability. Further, the limited resources of wireless sensor nodes demand an energy-efficient operation of the multicast protocol. Current data dissemination schemes do not fulfil all of the above requirements. In order to close the gap, we designed the Sensor Node Overlay Multicast (SNOMC) protocol such that to support a reliable, time-efficient and energy-efficient dissemination of data from one sender node to multiple receivers. In contrast to other multicast transport protocols, which do not support reliability mechanisms, SNOMC supports end-to-end reliability using a NACK-based reliability mechanism. The mechanism is simple and easy to implement and can significantly reduce the number of transmissions. It is complemented by a data acknowledgement after successful reception of all data fragments by the receiver nodes. In SNOMC three different caching strategies are integrated for an efficient handling of necessary retransmissions, namely, caching on each intermediate node, caching on branching nodes, or caching only on the sender node. Moreover, an option was included to pro-actively request missing fragments. SNOMC was evaluated both in the OMNeT++ simulator and in our in-house real-world testbed and compared to a number of common data dissemination protocols, such as Flooding, MPR, TinyCubus, PSFQ, and both UDP and TCP. The results showed that SNOMC outperforms the selected protocols in terms of transmission time, number of transmitted packets, and energy-consumption. Moreover, we showed that SNOMC performs well with different underlying MAC protocols, which support different levels of reliability and energy-efficiency. Thus, SNOMC can offer a robust, high-performing solution for the efficient distribution of code updates and management information in a wireless sensor network. To address the three management tasks, in this thesis we developed the Management Architecture for Wireless Sensor Networks (MARWIS). MARWIS is specifically designed for the management of heterogeneous wireless sensor networks. A distinguished feature of its design is the use of wireless mesh nodes as backbone, which enables diverse communication platforms and offloading functionality from the sensor nodes to the mesh nodes. This hierarchical architecture allows for efficient operation of the management tasks, due to the organisation of the sensor nodes into small sub-networks each managed by a mesh node. Furthermore, we developed a intuitive -based graphical user interface, which allows non-expert users to easily perform management tasks in the network. In contrast to other management frameworks, such as Mate, MANNA, TinyCubus, or code dissemination protocols, such as Impala, Trickle, and Deluge, MARWIS offers an integrated solution monitoring, configuration and code updating of sensor nodes. Integration of SNOMC into MARWIS further increases performance efficiency of the management tasks. To our knowledge, our approach is the first one, which offers a combination of a management architecture with an efficient overlay multicast transport protocol. This combination of SNOMC and MARWIS supports reliably, time- and energy-efficient operation of a heterogeneous wireless sensor network.

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El desarrollo del capitalismo en el agro ha dado lugar a numerosas transformaciones y a diversos trabajos que reflexionan en torno a este suceso social. En el marco de una nueva ruralidad asociada a una agricultura en transformación y altamente tecnologizada, el presente estudio se construye en base a un análisis acerca de las relaciones que se establecen entre hombres y mujeres en tres comunas del sur de la Provincia de Santa Fe, zona núcleo de la Región Pampeana. Para llevar adelante dicho objetivo hemos escogido, como dimensiones de aproximación principales del análisis: los niveles de educación formal, los espacios de sociabilidad, la economía del hogar, el acceso a la tierra y las prácticas sucesorias. Una muestra estadísticamente representativa de 1.082 casos, junto a observaciones, entrevistas desestructuradas y registros etnográficos, han sido los insumos principales para un abordaje cuali-cuantitativo de los asuntos en cuestión.