Sounds good? Determination of a gas/brine interface by an acoustic method at Manosque

International audienceWater hammers commonly are observed at wellheads and often are considered a potential hazard that should be avoided. Nevertheless, there are a few situations in which water hammers provide very valuable information about a well. A comprehensive data-acquisition and analysis system has been developed by Brouard Consulting and Ecole Polytechnique. One potential application of that system is determining the depth of an interface between two fluids. This application has been tested successfully at the Manosque field. It is demonstrated here how this low-cost and non-intrusive system can be accurate and allows practical, real-time measurements

Recent numerical models for engineering studies in open channels of power plants

Water Qualit

Influence of Environment and Mitochondrial Heritage on the Ecological Characteristics of Fish in a Hybrid Zone

Ecological characteristics (growth, morphology, reproduction) arise from the interaction between environmental factors and genetics. Genetic analysis of individuals' life history traits might be used to improve our understanding of mechanisms that form and maintain a hybrid zone.A fish hybrid zone was used to characterize the process of natural selection. Data were collected during two reproductive periods (2001 and 2002) and 1117 individuals (nase, Chondrostama nasus nasus, sofie C. toxostoma toxostoma and hybrids) were sampled. Reproductive dates of the two parental species overlapped at sympatric sites. The nase had an earlier reproductive period than the sofie; males had longer reproductive periods for both species. Hybridisation between female nase and male sofie was the most likely. Hybrids had a reproductive period similar to the inherited parental mitochondrial type. Growth and reproductive information from different environments has been synthesised following a bayesian approach of the von Bertalanffy model. Hybrid life history traits appear to link with maternal heritage. Hybrid size from the age of two and size at first maturity appeared to be closer to the size of the maternal origin species (nase or sofie). Median growth rates for hybrids were similar and intermediate between those of the parental species. We observed variable life history traits for hybrids and pure forms in the different parts of the hybrid zone. Geometrical analysis of the hybrid fish shape gave evidence of two main morphologies with a link to maternal heritage.Selective mating seemed to be the underlying process which, with mitochondrial heritage, could explain the evolution of the studied hybrid zone. More generally, we showed the importance of studies on hybrid zones and specifically the study of individuals' ecological characteristics, to improve our understanding of speciation

Hill by Jean Giono

A review of Jean Giono\u27s Hill

Rural Urbanity and Rural Metropolises as Emerging Patterns of Urban Growth

The processes of metropolitanization must explain if and how they concern some specific areas, how and if they primarily concern networks, hubs and nodes, pushing into the background the immediate territories of the metropolis. We assume that small-sized areas, in particular rural zones, could constitute a level of implementation of metropolitan processes. The study area for the empirical analysis reported here is the Regional Natural Reserve of Luberon. The phenomenon of diffuse metropolitanization is both appreciated in comparison to standard and innovative urban forms. The analyses of the structuring and the functioning of this rural area highlight the emergence of new patterns of urbanity and new territorial-type configuration, as the \"rural metropolis\". The notion of intensity and a set of social representations found the argumentation.Metropolitanization, Rural Areas, Rural Urbanity, Spatial Morphology, Emergence

L'évolution récente commerces ruraux (1980-2005)

La disparition des services au cours des deux dernières décennies dans les espaces ruraux, prive 90% des communes des Alpes de Haute-Provence de commerces basiques, tandis qu'une dynamique marchande sélective profite aux deux villes moyennes et à quelques communes dont la fonction touristique domine. Pourtant, des enquêtes effectuées auprès de la préfecture, des mairies, et des organismes marchands, permettent de quantifier l'émergence de nouvelles stratégies de ventes et de pratiques adaptatives des ménages ruraux face à la concentration commerciale. Aujourd'hui, les activités quotidiennes s'exercent sur un espace élargi et augmentent les distances d'approvisionnement pour les ménages. Dans ce rapport à l'espace de plus en plus distendu, et en dépit de l'augmentation des ventes par correspondance, s'amorcent des relations de proximité qui relèvent de la mise en réseau, de la mutualisation des lieux et, in fine, de l'acte de socialisation