88 resultados para IFC


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The aim of this thesis was to investigate the respective contribution of prior information and sensorimotor constraints to action understanding, and to estimate their consequences on the evolution of human social learning. Even though a huge amount of literature is dedicated to the study of action understanding and its role in social learning, these issues are still largely debated. Here, I critically describe two main perspectives. The first perspective interprets faithful social learning as an outcome of a fine-grained representation of others’ actions and intentions that requires sophisticated socio-cognitive skills. In contrast, the second perspective highlights the role of simpler decision heuristics, the recruitment of which is determined by individual and ecological constraints. The present thesis aims to show, through four experimental works, that these two contributions are not mutually exclusive. A first study investigates the role of the inferior frontal cortex (IFC), the anterior intraparietal area (AIP) and the primary somatosensory cortex (S1) in the recognition of other people’s actions, using a transcranial magnetic stimulation adaptation paradigm (TMSA). The second work studies whether, and how, higher-order and lower-order prior information (acquired from the probabilistic sampling of past events vs. derived from an estimation of biomechanical constraints of observed actions) interacts during the prediction of other people’s intentions. Using a single-pulse TMS procedure, the third study investigates whether the interaction between these two classes of priors modulates the motor system activity. The fourth study tests the extent to which behavioral and ecological constraints influence the emergence of faithful social learning strategies at a population level. The collected data contribute to elucidate how higher-order and lower-order prior expectations interact during action prediction, and clarify the neural mechanisms underlying such interaction. Finally, these works provide/open promising perspectives for a better understanding of social learning, with possible extensions to animal models.

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The motor system can no longer be considered as a mere passive executive system of motor commands generated elsewhere in the brain. On the contrary, it is deeply involved in perceptual and cognitive functions and acts as an “anticipation device”. The present thesis investigates the anticipatory motor mechanisms occurring in two particular instances: i) when processing sensory events occurring within the peripersonal space (PPS); and ii) when perceiving and predicting others’actions. The first study provides evidence that PPS representation in humans modulates neural activity within the motor system, while the second demonstrates that the motor mapping of sensory events occurring within the PPS critically relies on the activity of the premotor cortex. The third study provides direct evidence that the anticipatory motor simulation of others’ actions critically relies on the activity of the anterior node of the action observation network (AON), namely the inferior frontal cortex (IFC). The fourth study, sheds light on the pivotal role of the left IFC in predicting the future end state of observed right-hand actions. Finally, the fifth study examines how the ability to predict others’ actions could be influenced by a reduction of sensorimotor experience due to the traumatic or congenital loss of a limb. Overall, the present work provides new insights on: i) the anticipatory mechanisms of the basic reactivity of the motor system when processing sensory events occurring within the PPS, and the same anticipatory motor mechanisms when perceiving others’ implied actions; ii) the functional connectivity and plasticity of premotor-motor circuits both during the motor mapping of sensory events occurring within the PPS and when perceiving others’ actions; and iii) the anticipatory mechanisms related to others’ actions prediction.

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There are several heat and mass diffusion problems which affect to the IFC chamber design. New simulation models and experiments are needed to take into account the extreme conditions due to ignition pulses and neutron flux

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Accumulating evidence suggests a role for the medial temporal lobe (MTL) in working memory (WM). However, little is known concerning its functional interactions with other cortical regions in the distributed neural network subserving WM. To reveal these, we availed of subjects with MTL damage and characterized changes in effective connectivity while subjects engaged in WM task. Specifically, we compared dynamic causal models, extracted from magnetoencephalographic recordings during verbal WM encoding, in temporal lobe epilepsy patients (with left hippocampal sclerosis) and controls. Bayesian model comparison indicated that the best model (across subjects) evidenced bilateral, forward, and backward connections, coupling inferior temporal cortex (ITC), inferior frontal cortex (IFC), and MTL. MTL damage weakened backward connections from left MTL to left ITC, a decrease accompanied by strengthening of (bidirectional) connections between IFC and MTL in the contralesional hemisphere. These findings provide novel evidence concerning functional interactions between nodes of this fundamental cognitive network and sheds light on how these interactions are modified as a result of focal damage to MTL. The findings highlight that a reduced (top-down) influence of the MTL on ipsilateral language regions is accompanied by enhanced reciprocal coupling in the undamaged hemisphere providing a first demonstration of “connectional diaschisis.”

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IP Multimedia Subsystem (IMS) is considered to provide multimedia services to users through an IP-based control plane. The current IMS service invocation mechanism, however, requires the Serving-Call Session Control Function (S-CSCF) invokes each Application Server (AS) sequentially to perform service subscription pro?le, which results in the heavy load of the S-CSCF and the long session set-up delay. To solve this issue, this paper proposes a linear chained service invocation mechanism to invoke each AS consecutively. By checking all the initial Filter Criteria (iFC) one-time and adding the addresses of all involved ASs to the ?Route? header, this new approach enables multiple services to be invoked as a linear chain during a session. We model the service invocation mechanisms through Jackson networks, which are validated through simulations. The analytic results verify that the linear chained service invocation mechanism can effectively reduce session set-up delay of the service layer and decrease the load level of the S-CSCF

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In this work the use of ESS-Bilbao fast neutron lines for irradiation of materials for nuclear fusion is studied. For the comparison of ESS-Bilbao with an inertial fusion facility a simplified model of HiPER chamber has been used. Several positions for irradiation at ESS-Bilbao have been also compared. The material chosen for the damage analysis is silica due to its importance on IFC optics. In this work a detailed comparison between the two facilities for silica irradiation is given. The comparison covers the neutron fluxes, doses, defect production and PKA spectra. This study is also intended as a methodological approach or guideline for future works on other materials.

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Diverses publications soulignent l'augmentation de l'espérance de vie et avec elle, le vieillissement mondial de la population. Ce processus se poursuivra à l'avenir, ainsi que son influence sur l’incidence et la prévalence de l'incapacité. Chez les personnes âgées, l’incapacité, les maladies chroniques et leur association constituent un sujet important dans le domaine de la santé publique en raison de l'effet qu'ils ont sur la demande des services de santé. Le but de ce mémoire est d’examiner quelle est la contribution respective des maladies chroniques et de l'incapacité dans l'utilisation des services de santé chez les personnes âgées et de leur interaction. Il s’agit de savoir si l'association entre la maladie chronique et l'utilisation des services de santé est modifiée par l’incapacité prenant en compte les caractéristiques de l'individu et son environnement. Ce travail est basé sur le modèle comportemental proposé par Andersen et Newman et le modèle du processus d’incapacité de Verbrugge et Jette. Pour répondre à l’objectif, nous utilisons les données du projet de recherche “ FRéLE ” (Fragilité, une étude longitudinale de ses expressions), réalisé durant la période 2010 -2013 auprès d’un échantillon de 1643 personnes âgées vivant dans la communauté au Québec. L’incapacité est évaluée à l’aide de deux indicateurs : les AVQ et les AVD. Les maladies chroniques sont mesurées par l’indice fonctionnel de comorbidité (IFC). La dépression est évaluée selon les critères de l’échelle de dépression gériatrique (EDG). L’état cognitif est mesuré par l'évaluation cognitive de Montréal (MoCA). Les facteurs de prédisposition comportent l’âge, le sexe, l’ethnicité et le niveau scolaire. Les facteurs facilitateurs incluent le revenu et le réseau social, ce dernier étant mesure par la présence ou non d’une personne de soutien et son lien avec la personne âgée. Divers modèles de régression sont adoptés pour identifier les facteurs statistiquement significatifs du modèle comportemental d’Andersen et Newman et du modèle du processus d’incapacité de Verbrugge et Jette. Nos résultats ont montré que, si le rôle des prédicteurs de l’utilisation varie en fonction du type de services de santé utilisé, l’utilisation s’accroît principalement avec le nombre de maladies chroniques. En ce qui concerne l’interaction entre la maladie chronique et l’incapacité, nos résultats ont révélé que l’interaction n’est statistiquement significative pour aucun des services analysés. Compte tenu de la diversité et les besoins de la population âgée, caractérisée par une prévalence élevée de maladies chroniques et d'incapacités, l’étude des facteurs impliqués dans l'utilisation des services de santé sera utile pour la mise en œuvre d’une offre de services, plus conforme aux besoins de cette population

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Diverses publications soulignent l'augmentation de l'espérance de vie et avec elle, le vieillissement mondial de la population. Ce processus se poursuivra à l'avenir, ainsi que son influence sur l’incidence et la prévalence de l'incapacité. Chez les personnes âgées, l’incapacité, les maladies chroniques et leur association constituent un sujet important dans le domaine de la santé publique en raison de l'effet qu'ils ont sur la demande des services de santé. Le but de ce mémoire est d’examiner quelle est la contribution respective des maladies chroniques et de l'incapacité dans l'utilisation des services de santé chez les personnes âgées et de leur interaction. Il s’agit de savoir si l'association entre la maladie chronique et l'utilisation des services de santé est modifiée par l’incapacité prenant en compte les caractéristiques de l'individu et son environnement. Ce travail est basé sur le modèle comportemental proposé par Andersen et Newman et le modèle du processus d’incapacité de Verbrugge et Jette. Pour répondre à l’objectif, nous utilisons les données du projet de recherche “ FRéLE ” (Fragilité, une étude longitudinale de ses expressions), réalisé durant la période 2010 -2013 auprès d’un échantillon de 1643 personnes âgées vivant dans la communauté au Québec. L’incapacité est évaluée à l’aide de deux indicateurs : les AVQ et les AVD. Les maladies chroniques sont mesurées par l’indice fonctionnel de comorbidité (IFC). La dépression est évaluée selon les critères de l’échelle de dépression gériatrique (EDG). L’état cognitif est mesuré par l'évaluation cognitive de Montréal (MoCA). Les facteurs de prédisposition comportent l’âge, le sexe, l’ethnicité et le niveau scolaire. Les facteurs facilitateurs incluent le revenu et le réseau social, ce dernier étant mesure par la présence ou non d’une personne de soutien et son lien avec la personne âgée. Divers modèles de régression sont adoptés pour identifier les facteurs statistiquement significatifs du modèle comportemental d’Andersen et Newman et du modèle du processus d’incapacité de Verbrugge et Jette. Nos résultats ont montré que, si le rôle des prédicteurs de l’utilisation varie en fonction du type de services de santé utilisé, l’utilisation s’accroît principalement avec le nombre de maladies chroniques. En ce qui concerne l’interaction entre la maladie chronique et l’incapacité, nos résultats ont révélé que l’interaction n’est statistiquement significative pour aucun des services analysés. Compte tenu de la diversité et les besoins de la population âgée, caractérisée par une prévalence élevée de maladies chroniques et d'incapacités, l’étude des facteurs impliqués dans l'utilisation des services de santé sera utile pour la mise en œuvre d’une offre de services, plus conforme aux besoins de cette population

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The Spanish transition, the political process through which Spain ceased to be a dictatorship to become a democracy, was accompanied by the dissolution of the National Movement, the institutional support for the chain of the Movement Press from its beginnings, in April 1977. This fact, among others, contributed to the /Sur/, the regional reference newspaper for the chain in Andalusia, evolving both structurally and ideologically to adapt itself to the new political regime. This study applies content analysis to editorials, articles and columns published by the newspaper between 1975 and 1978, exploring the process through which the regional newspaper edited in Málaga abandoned its propaganda function with regard to the Government, considering it undemocratic, and supported the PSOE, presenting it as the best alternative to the UCD in the Spanish Executive, thus taking on its role as a political agent.

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This paper studies the novel The Kindly Ones, whose main plot charts the anguished memories of a Nazi officer. The reader of this novel is plunged into the harshest atrocities of the Holocaust and WWII, as these are recounted by a perverse conscience who is unmoved by the most terrible actions. Fiction and reality are contrasted in the novel against the framework of history writing and the subsequent debates sparked by historical elaboration. This novel perceptively captures historical truth, thus calling for critical attention upon the collective responsibility which will prevent the repetition of events.

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The Department of Health has published a report entitled - An assessment of the economic cost of smoking in Ireland.  The study was carried out for the Department of Health by ICF International.  The purpose of this study is to contribute to the evidence base of tobacco consumption and its effects in Ireland, to help support the implementation of the recommendations made in The Tobacco Free Ireland report (2013).

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No Submédio do Vale do São Francisco, Nordeste do Brasil, o cancro bacteriano da videira causado pela Xanthomonas campestris pv. viticola ocasiona grandes prejuízos em genótipos suscetíveis. O objetivo foi avaliar à resistência de genótipos de videira quanto ao cancro bacteriano. Dois experimentos (I e II) com 17 e 36 genótipos, respectivamente, com cinco repetições, foram conduzidos em casa de vegetação com temperatura e umidade médias de 30ºC e 70%. As plantas foram inoculadas com suspensão do isolado bacteriano por fricção com gaze umedecidas com solução bacteriana (A570= 6×108 UFC/ml), incubadas e observadas diariamente quanto aos parâmetros pidemiológicos: período de incubação (PI); incidência de folhas com sintomas (INC); incidência de folhas com cancro (IFC); severidade da doença (SEV); e área abaixo da curva de progresso da SEV (AACPSD), calculada como ∑(yi+yi+1)/2dti. O delineamento estatístico foi inteiramente casualizado. Todos os genótipos foram suscetíveis ao patógeno, mas diferiram significativamente entre si (P=0,05). No grupo I destacaram Itália Melhorada e ?Red Globe? com níveis elevados para todos os parámetros, resultado observado no grupo II apenas para Red Globe. No experimento I, Petit Verdot, BRS Cora e Moscato apresentaram os maiores PI e os menores INC, IFC, SEV e AACPSD; já no experimento II, foram 12 genótipos com menores níveis para todas as variáveis, indicando grande potencial para melhoramento genético e manejo integrado. No agrupamento pelo UPGMA (similaridade 60%) formaram-se cinco grupos no experimento I; e seis no II.

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Introduction: Brazil, is one of the main agricultural producers in the world ranking 1st in the production of sugarcane, coffee and oranges. It is also 2nd as world producer of soybeans and a leader in the harvested yields of many other crops. The annual consumption of mineral fertilizers exceeds 20 million mt, 30% of which corresponds to potash fertilizers (ANDA, 2006). From this statistic it may be supposed that fertilizer application in Brazil is rather high, compared with many other countries. However, even if it is assumed that only one fourth of this enormous 8.5 million km2 territory is used for agriculture, average levels of fertilizer application per hectare of arable land are not high enough for sustainable production. One of the major constraints is the relatively low natural fertility status of the soils which contain excessive Fe and Al oxides. Agriculture is also often practised on sandy soils so that the heavy rainfall causes large losses of nutrients through leaching. In general, nutrient removal by crops such as sugarcane and tropical fruits is much more than the average nutrient application via fertilization, especially in regions with a long history of agricultural production. In the recently developed areas, especially in the Cerrado (Brazilian savanna) where agriculture has expanded since 1980, soils are even poorer than in the "old" agricultural regions, and high costs of mineral fertilizers have become a significant input factor in determining soybean, maize and cotton planting. The consumption of mineral fertilizers throughout Brazil is very uneven. According to the 1995/96 Agricultural Census, only in eight of the total of 26 Brazilian states, were 50 per cent or more of the farms treated "systematically" with mineral fertilizers; in many states it was less than 25 per cent, and in five states even less than 12 per cent (Brazilian Institute for Geography and Statistics; Censo Agropecuario1995/96, Instituto Brazileiro de Geografia e Estadistica; IBGE, www.ibge.gov.br). The geographical application distribution pattern of mineral fertilizers may be considered as an important field of research. Understanding geographical disparities in fertilization level requires a complex approach. This includes evaluation of the availability of nutrients in the soil (and related soil properties e.g. CEC and texture), the input of nutrients with fertilizer application, and the removal of nutrients by harvested yields. When all these data are compiled, it is possible to evaluate the balance of particular nutrients for certain areas, and make conclusions as to where agricultural practices should be optimized. This kind of research is somewhat complicated, because it relies on completely different sources of data, usually from incomparable data sources, e.g. soil characteristics attributed to soil type areas, in contrast to yields by administrative regions, or farms. A priority tool in this case is the Geographical Information System (GIS), which enables attribution of data from different fields to the same territorial units, and makes possible integration of these data in an "inputoutput" model, where "input" is the natural availability of a nutrient in the soil plus fertilization, and "output" export of the same nutrient with the removed harvested yield.