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Dynamic functional connectivity, as measured by the time-varying covariance of neurological signals, is believed to play an important role in many aspects of cognition. While many methods have been proposed, reliably establishing the presence and characteristics of brain connectivity is challenging due to the high dimensionality and noisiness of neuroimaging data. We present a latent factor Gaussian process model which addresses these challenges by learning a parsimonious representation of connectivity dynamics. The proposed model naturally allows for inference and visualization of time-varying connectivity. As an illustration of the scientific utility of the model, application to a data set of rat local field potential activity recorded during a complex non-spatial memory task provides evidence of stimuli differentiation.

To offset the effects of soil sealing and to deal with stormwater management issue s , cities have adopted BMPs (Best Management Practices) for twenty years . Many facilities exist on urban areas and h ave proved to be efficient on a hydrological point of view, but questions remain about pollutants. Under the Matriochkas project, w h ich focuses on performances of stormwater management facilities in terms of retention of pollutants, an inventory on retention and infiltration basins and swales is conducted throughout the Nantes metropole territory. An exhaustive diagnosis of sources of pollutants is carried out on the facilities identifi ed in this inventory, using a methodology based on spatial analysis of geographic data. More specifically, contributive area of facilities is identified by an automatic method based on drainage networks. The description of these contributive areas in terms of geographic data (land use, human activities such as road traffic , and practices ), and literature data on emissions of pollutants in urban areas, makes it possible to estimate potential pollutant loads which discharge into these facilities., Afin de compenser les effets de l'imperméabilisation des sols et pour répondre à la problématique de gestion des eaux pluviales, les collectivités se tournent depuis une vingtaine d'années vers les techniques alternatives. De nombreux ouvrages existent sur les territoires urbains, et si leurs performances hydrologiques sont connues, leur rôle vis-à-vis de la rétention des polluants l'est moins. Dans le cadre du projet Matriochkas, qui s'intéresse aux performances des ouvrages de gestion à la source vis-à-vis de la rétention des polluants, un recensement des bassins de rétention et d'infiltration ainsi que des noues est mené sur l'ensemble de l'agglomération nantaise. Un diagnostic exhaustif des sources de pollution est réalisé sur les ouvrages identifiés dans ce recensement, en utilisant une méthodologie basée sur l'exploitation de données géographiques. Cette méthodologie consiste à déterminer la zone contributive des ouvrages en développant une méthode automatique qui s'appuie sur les réseaux de drainage. La description de ces zones contributives à partir de données géographiques (occupation du sol, activités anthropiques dont le trafic routier, et usages) et de données de la littérature relatives aux émissions de polluants sur les surfaces urbaines, permet d'estimer a priori les flux de polluants déversés dans ces ouvrages.

National audience; Grape vines are one of the few crops in the world that is cropped only as a pure crop system. Vineyards face severe environmental concerns such as soil degradation, heavy loads of pesticides and pests attacks. In Roman times, vineyard cultivation was performed as an agroforestry system called Arbustra, with vines growing on living trees used as trellises. Scattered trees such as peach, almond or olive trees were also grown in vineyards in Europe until recently. These trees have been destroyed to allow easy mechanisation of the vineyard management, including mechanical harvesting of grapes. New vineyard agroforestry plots were set up in 1996 in the south of France, and have been monitored since then for grape production and tree growth. Various tree species were introduced into vineyards, at a density of 222 trees/ha, on shallow rocky soils prone to drought. Both evergreen resinous and broadleaved deciduous tree species were introduced, with Sorbus domestica (Service tree) and Pinus pinea (Stone pine) as the key species. Control plots with pure tree and pure vine plantation were available. After 12 years of cultivation, grape production and tree growth data showed that vineyard agroforestry is possible. Tree growth is enhanced in the agroforestry system, and grape production is not yet reduced by tree competition, except on extremely shallow soils. Competition for water and/or nutrients appears to be the main limiting factor, while light competition seems not to be a problem so far. Root pruning with a sub-soiler was used to limit water competition by the trees on the vines and proved useful. Some preliminary assessments of pest predators in the vineyard system show that mite control may be enhanced by the presence of trees in vineyards. This could allow a reduction in the use of pesticides in vineyards, but more detailed studies are needed to con!rm this hypothesis

International audience; Coffee and vine are both perennial plants that are cultivated for their fruits on large areas in tropical and Mediterranean areas respectively. They are very similar in their structure with signicant areas of bare soil. Coffee is mostly grown in agroforestry systems, while vineyards are grown mostly as pure crops. Heavy pesticide use, soil degradation and loss of biodiversity are problems faced by both systems. Therefore, the use of trees in both systems may target some common problems, such as water contamination or pest control. In this paper we address two questions: 1) What lessons could be learned from coffee systems regarding the use of trees?; and 2) What are the differences in light competition with trees at different latitudes (Mediterranean versus tropical)? Shade is sought for coffee production in the tropics, but light competition by trees is considered detrimental for vine growing. However, vine was originally grown as an agroforestry system. The dynamic prediction of radiation patterns below the canopy of wide-spaced trees is essential to predict the outcome of agroforestry systems. A light competition model was used to calculate the impact of various tree canopy sizes and tree-row orientations on the distribution of the light at the coffee or vine level. For a given tree density and tree leaf area, the in!uence of the shape of the tree crown on the light availability for the crop is discussed. Surprisingly, erected and !at canopies were equivalent in the Mediterranean zone, but induced very different light patterns for the crop in the tropics. Tree-row direction was essential in Mediterranean latitudes and important in tropical latitudes to obtain a homogeneous radiation on the crop, which is counter-intuitive. Practical consequences for the choice and the management of shade trees with perennial crops are discussed

National audience

ISBN : 2-9200-2157-5; Confrontée aux bouleversements que subit la planète, aux révolutions technologiques et scientifiques, la Francophonie doit se positionner face à une évolution mondiale pour faire entendre sa voix dans le concert des régions et recrutements politiques, économiques ou culturels. Les États généraux de la Francophonie scientifique ont réuni les spécialistes des sujets définis comme autant de priorités pour l'avenir du français comme langue de communication internationale. Cet ouvrage qui présente l'ensemble des interventions de personnalités politiques, scientifiques et universitaires, propose des solutions concrètes à la définition d'une politique globale en faveur de la promotion de la langue française dans les secteurs d'activité stratégiques : les autoroutes de l'information, l'économie, l'enseignement, l'ingénierie linguistique, les médias, la science.

Confrontée aux bouleversements que subit la planète, aux révolutions technologiques et scientifiques, la Francophonie doit se positionner face à une évolution mondiale pour faire entendre sa voix dans le concert des régions et recrutements politiques, économiques ou culturels. Les États généraux de la Francophonie scientifique ont réuni les spécialistes des sujets définis comme autant de priorités pour l'avenir du français comme langue de communication internationale. Cet ouvrage qui présente l'ensemble des interventions de personnalités politiques, scientifiques et universitaires, propose des solutions concrètes à la définition d'une politique globale en faveur de la promotion de la langue française dans les secteurs d'activité stratégiques : les autoroutes de l'information, l'économie, l'enseignement, l'ingénierie linguistique, les médias, la science.

Numéro de référence interne originel : a1.4 g 302

This study is a part of pluridisciplinary project on the assessment of the environmental impacts of an urban mobility plan and of their socio-economic consequences. Particularly, one of the objectives of the project is to be able to build and to compare soundmaps (or noise maps) of large cities, in function of several mobility plan parameters. Considering the computational time that is required for making noise maps with classical software, a simplified approach of sound propagation in urban areas has been proposed. The particular interest of the proposed approach is that the model has been integrated within a two-dimensional geographic information system software, and is able to produce full noise map in few hours only. The heart of the model is based on French standard NMPB2008 method, whose noise emission and sound propagation calculations have been simplified. In addition, in order to reduce computational times and memory resources, algorithms have been optimized for the calculation of the direct, reflected and scattered field in large urban areas.

Considerable concern has recently been expressed worldwide about growing income inequality. Much of the discussion, though, has been in general terms and focused on the US experience. To understand whether and how Canada ought to respond to this development, we need to be clear on the facts. This paper documents Canadian patterns in income inequality and investigates the top 1 percent of earners—the group receiving the most attention. We summarize what is known about the causes of growing income inequality, including the role of gender wage differences. Finally, we outline policy options for reducing—or slowing the growth of—inequality.