The 8 and 9 September 2002 flash flood event in France: a model intercomparison

Within the framework of the European Interreg IIIb Medocc program, the HYDROPTIMET project aims at the optimization of the hydrometeorological forecasting tools in the context of intense precipitation within complex topography. Therefore, some meteorological forecast models and hydrological models were tested on four Mediterranean flash-flood events. One of them occured in France where the South-eastern ridge of the French “Massif Central”, the Gard region, experienced a devastating flood on 8 and 9 September 2002. 24 people were killed during this event and the economic damage was estimated at 1.2 billion euros. To built the next generation of the hydrometeorological forecasting chain that will be able to capture such localized and fast events and the resulting discharges, the forecasted rain fields might be improved to be relevant for hydrological purposes. In such context, this paper presents the results of the evaluation methodology proposed by Yates et al. (2005) that highlights the relevant hydrological scales of a simulated rain field. Simulated rain fields of 7 meteorological model runs concerning with the French event are therefore evaluated for different accumulation times. The dynamics of these models are either based on non-hydrostatic or hydrostatic equation systems. Moreover, these models were run under different configurations (resolution, initial conditions). The classical score analysis and the areal evaluation of the simulated rain fields are then performed in order to put forward the main simulation characteristics that improve the quantitative precipitation forecast. The conclusions draw some recommendations on the value of the quantitative precipitation forecasts and way to use it for quantitative discharge forecasts within mountainous areas

Evolution of interactions between water and native corn starch as a function of moisture content

International audienc

Heart valve bioprothesis; effect of different acellularizations methods on the biomechanical and morphological properties of porcine aortic and pulmonary valve

Tissue engineering is a promising tool for the creation of a new type of the heart valve bioprothesis. The biological scaffold composed of decellularized tissue has been successfully used for the constructions of the valve prosthesis. An analysis of the efficiency of the valve leaflet acellularization methods and the influence of those methods on the morphology and the biomechanical properties of the ECM (extra cellular matrix) was performed. Fresh porcine hearts obtained from a slaughterhouse were used in the experiments. The efficiency of the acellularization methods was dependent on the tissue type and the acellularoization methods used. The more effective were the enzymatic methods, both because of the cell removal efficiency and the effect on the biomechanical properties of the heart valve. The differences in the biomechanical and morphological properties of the porcine aortic and the pulmonary valve after different types of the acellularization process could influence the hemodynamic conditions of the heart after the valve replacement, which limited the range of the tissue types used for the creations of the tissue engineered heart valve