Geographical downscaling of outputs provided by an economic farm model calibrated at the regional level

International audienceThere is a strong need for accurate and spatially referenced information regarding policy making and model linkage. This need has been expressed by land users, and policy and decision makers in order to estimate both spatially and locally the impacts of European policy (like the Common Agricultural Policy) and/or global changes on farm-groups. These entities are defined according to variables such as altitude, economic size and type of farming (referring to land uses). European farm-groups are provided through the Farm Accountancy Data Network (FADN) as statistical information delivered at regional level. The aim of the study is to map locally farm-group probabilities within each region. The mapping of the farm-groups is done in two steps: (1) by mapping locally the co-variables associated to the farm-groups, i.e. altitude and land uses; (2) by using regional FADN data as a priori knowledge for transforming land uses and altitude information into farm-groups location probabilities within each region. The downscaling process focuses on the land use mapping since land use data are originally point information located every 18 km. Interpolation of land use data is done at 100 m by using co-variables like land cover, altitude, climate and soil data which are continuous layers usually provided at fine resolution. Once the farm-groups are mapped, European Policy and global changes scenarios are run through an agro-economic model for assessing environmental impacts locally

Color wavelet Maxima

In this article, we propose a representation scheme based on wavelet maxima for color images representation. Wavelet maxima constitute a multi-scale edge decomposition which can be processed using classic techniques of contour study but which have the property of being empirically inversable. We propose to adapt this representation to color images. For this, we extend the multi-scale gradient decomposition. Then, by using classical definitions of the color edges, a color maxima wavelet representation is defined, which shows the edge evolution through the scales. By applying Mallat's iterative reconstruction algorithm, two reconstructions are presented: a grayscale image that gives information about the edge detected in the color space and a color image that can constitute the result of a denoising algorithm. Finaly, we propose to introduce segmentation based region to this new representation in order to obtain a more robust edge selection. This strategy is illustrated with denoising application.Dans cet article, nous proposons un schéma de représentation multiéchelle pour les images couleur utilisant les maxima d'ondelettes. Les maxima d'ondelettes constituent une décomposition en contours multiéchelle, qui peut être traitée par les techniques classiques d'études de contour, mais qui possède la propriété d'être empiriquement inversible. Nous proposons d'adapter cette représentation aux images couleur. Pour cela, nous calculons la décomposition en gradient multiéchelle couleur suivant une approche marginale. Ensuite, en utilisant les définitions classiques des contours couleur à partir du gradient, une représentation couleur multiéchelle est définie qui illustre l'évolution des contours couleur à travers les échelles. En appliquant l'algorithme itératif d'inversion de Mallat, nous proposons deux reconstructions possibles : une image en niveaux de gris qui caractérise les différents contours détectés et une image couleur qui peut constituer le résultat d'un débruitage si la représentation en maxima d'ondelettes a été au préalable seuillée. Enfin, nous proposons d'intégrer dans la représentation en maxima des algorithmes de segmentation région couleur, ceci afin de fournir une sélection des contours plus robustes. Cette dernière étape est illustrée dans le cadre de la restauration de données couleur bruitées

Theory of high-order harmonic generation by an elliptically polarized laser field

We generalize a recently formulated theory of high-order harmonic generation by low-frequency laser fields [Anne L'Huillier et al., Phys. Rev. A 48, R3433 (1993)] to the case of an elliptically polarized light. Our theoretical description includes both the single-atom response and propagation. Phase matching significantly modifies the results obtained in the single-atom response. The results of our calculations, including propagation for both the intensity and polarization properties of harmonics as a function of laser ellipticity, compare very well with recent experimental observations

Finite element model to simulate impact on a soft tissue simulant

A finite element model of an impact test on a soft tissue simulant, used as part of a shoulder surrogate, was developed in Ansys© LS-DYNA®. The surrogate consisted of a metal hemicylindrical core, with a diameter of 75 mm, covered with a 15 mm thick relaxed muscle simulant. The muscle simulant consisted of a 14 mm thick layer of silicone covered with 1 mm thick chamois leather to represent skin. The material properties of the silicone were obtained via quasi-static compression testing (curve fit with hyperelastic models) and compressive stress relaxation testing (curve fit with a Prony series). Outputs of the finite element models were compared against experimental data from impact tests on the shoulder surrogate at energies of 4.9, 9.8 and 14.7 J. The accuracy of the finite element models was assessed using four parameters: peak impact force, maximum deformation, impact duration and impulse. A 5-parameter Mooney-Rivlin material model combined with a 2-term Prony series was found to be suitable for modelling the soft tissue simulant of the shoulder surrogate. This model had under 10% overall mean deviation from the experimental values for the four assessment parameters across the three impact energies. Overall, the model provided a repeatable test method that can be adapted to help predict injuries to skin tissue and the performance/efficacy of personal protective equipment

The influence of oil extraction process of different rapeseed varieties on the ileal digestibility of crude protein and amino acids in broiler chickens

The current study assessed the effect of rapeseed variety and oil extraction process on the apparent and standardised ileal digestibility (AID, SID) of crude protein (CP) and amino acids (AA) in rapeseed co-products in broiler chickens. PR46W21 and DK Cabernet rapeseed varieties were de-oiled by soft and standard hexane extraction, producing soft rapeseed meal (SRSM) and rapeseed meal (RSM), respectively. The soft, non-standard hexane extraction method was designed to reduce heat treatment that occurs prior to hexane extraction in order to maximise potential genetic differences in digestibility values of rapeseed co-products. The test meals were incorporated into semi-synthetic diets at a level of 500 g/kg; diets were fed to 14-day old paired chickens (n = 6 pairs) for ten days, when ileal digesta was collected post-slaughter from Meckel’s diverticulum to the ileal-caecal junction. The AID and SID of CP and AA were determined using titanium dioxide as inert dietary marker. The variety PR46W21 showed a greater AID and SID of CP, arginine, leucine, methionine, cysteine, phenylalanine, valine and lysine in RSM compared to the DK Cabernet RSM (p < 0.05). The soft processing increased AID and SID of CP, histidine and lysine in SRSM of PR46W21 and DK Cabernet compared to their RSM counterparts (p < 0.05). An interaction between variety and processing was only observed for AID and SID of tryptophan (p < 0.001), as only in PR46W21 standard processing reduced the tryptophan SID compared to its soft processed counterpart. The data support the view that the selection of rapeseed variety and modification of thermal treatment during the oil extraction might improve nutritional value of rapeseed meals

Total partial and electron-capture cross sections for ionization of water vapor by 20-150 keV protons

IP

Reply to the comment on direct experimental evidence for a negative heat capacity in the liquid to gas phase transition in hydrogen cluster ions backbending of the caloric curve

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Prevalence of electrocardiographic abnormalities in West-Asian and African male athletes

International audienceOBJECTIVES: To evaluate the electrocardiographic (ECG) characteristics of West-Asian, black and Caucasian male athletes competing in Qatar using the 2010 recommendations for 12-lead ECG interpretation by the European Society of Cardiology (ESC). DESIGN: Cardiovascular screening with resting 12-lead ECG analysis of 1220 national level athletes (800 West-Asian, 300 black and 120 Caucasian) and 135 West-Asian controls was performed. RESULTS: Ten per cent of athletes presented with 'uncommon' ECG findings. Black African descent was an independent predictor of 'uncommon' ECG changes when compared with West-Asian and Caucasian athletes (p0.05). Seven athletes (0.6%) were identified with a disease associated with sudden death; this prevalence was two times higher in black athletes than in West-Asian athletes (1% vs 0.5%), and no cases were reported in Caucasian athletes and West-Asian controls. Eighteen West-Asian and black athletes were identified with repolarisation abnormalities suggestive of a cardiomyopathy, but ultimately, none were diagnosed with a cardiac disease. CONCLUSION: West-Asian and Caucasian athletes demonstrate comparable rates of ECG findings. Black African ethnicity is positively associated with increased frequencies of 'uncommon' ECG traits. Future work should examine the genetic mechanisms behind ECG and myocardial adaptations in athletes of diverse ethnicity, aiding in the clinical differentiation between physiological remodelling and potential cardiomyopathy or ion channel disorders

Molecular transport and flow past hard and soft surfaces: Computer simulation of model systems

The properties of polymer liquids on hard and soft substrates are investigated by molecular dynamics simulation of a coarse-grained bead-spring model and dynamic single-chain-in-mean-field (SCMF) simulations of a soft, coarse-grained polymer model. Hard, corrugated substrates are modelled by an FCC Lennard-Jones solid while polymer brushes are investigated as a prototypical example of a soft, deformable surface. From the molecular simulation we extract the coarse-grained parameters that characterise the equilibrium and flow properties of the liquid in contact with the substrate: the surface and interface tensions, and the parameters of the hydrodynamic boundary condition. The so-determined parameters enter a continuum description like the Stokes equation or the lubrication approximation.Comment: 41 pages, 13 figure

From Macroscopic to Microscopic: Experimental and Computational Methods to Investigate Bio-tribology

Tribology is an important factor (among other factors) during biological interactions of devices and tissues. The paper discusses how new computational and experimental methods can be used to understand and improve the design and development of medical devices at macro and micro scales to sustain life beyond 50 years. We have used pre-clinical experiments and computational methods to understand interactions between orthopaedic implants at the macro scale. The computational model has been validated with experiments. Now this computational model can predict damage in implants for different patients. One such application was successfully tried and tested in collaboration with University National Autonomous Mexico. This methodology can be used in future to design patient specific, affordable (using 3D printing) and robust implants which will be useful for developing countries like Vietnam, India and Mexico. Improvement of catheter designs is important to reduce damage to the internal tissues while being used for cardiovascular problems. We are developing new experimental techniques (in micro scale) that can be used to understand the interaction of cells with the catheter material. These will help reduce the hospital costs incurred during longer stay of the patients admitted for cardiovascular related problems