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Aedes albopictus and Aedes aegypti mosquitoes have a worldwide distribution and, as main vectors of dengue, chikungunya and Zika viruses, constitute a threat for public health both in tropical and temperate regions. To better target surveillance and control of Aedes-borne diseases, there is a need for tools with the capacity to predict the spatially distributed dynamics of mosquito vectors at a local scale. In addition, to be used by public health authorities and vector control services, such tools need easy-to-use interfaces allowing a customization by the user according to the geographical and entomological contexts. " ARBOCARTO " is a spatial modeling tool based on a generic mosquito life cycle- based model, driven by meteorological variables (temperature and rainfall). Its implementation considers the landscape context described from very high spatial imagery and/or ancillary data provided by the user, and the different functionalities allow the user to test different scenarios, such as the impact on mosquito dynamics of prevention measures (e.g., reduction of the number of breeding sites) or control actions (e.g., pulverization of insecticides). We present its application in various geographical contexts. In highly diverse environments and latitudes, the comparison between the model outputs and observed entomological data demonstrated the ability of " ARBROCARTO " tool to provide valuable complementary information to existing entomological surveillance programs. Thanks to its user-friendly interface, " ARBOCARTO " could be adopted by a broad community of managers involved in vector control.

Aedes albopictus and Aedes aegypti mosquitoes have a worldwide distribution and are well adapted to urban environments. Because they are the main vectors of dengue, chikungunya and Zika viruses, these two species constitute a threat for public health both in tropical and temperate regions. To better target surveillance and control of Aedes-borne diseases, there is a need for tools with the capacity to predict the spatially distributed dynamics of mosquito vectors at a local scale. In addition, to be used by public health authorities and vector control services, such tools need easy-to-use interfaces allowing a customization by the user according to the geographical and entomological contexts. Various approaches exist to model the dynamics of mosquito populations and to predict their spatial distribution. As mosquitoes depend closely on climatic and environmental conditions, satellite-based information (e.g. vegetation, urbanization type) can prove to be valuable input data for the model. Here, we provide both the scientific community and the operational stakeholders an efficient way for implementing a generic mosquito life cycle-based model, driven by meteorological variables (temperature and rainfall). The implementation of 'ARBOCARTO' considers the landscape context described from very high spatial imagery and/or ancillary data provided by the user. We present its application in various geographical contexts (mainland France and its overseas departments) and for two Aedes mosquitoes species population (Aedes albopictus and Ae. aegypti). In highly diverse environments and latitudes, the comparison between the model outputs and observed entomological data demonstrated the ability of 'ARBOCARTO' tool to provide valuable complementary information to existing entomological surveillance programs. The different functionalities allow the user to test different scenarios, such as the impact on mosquito dynamics of prevention measures (e.g., reduction of the number of breeding sites) or control actions (e.g., pulverization of insecticides). Thanks to its user-friendly interface, 'ARBOCARTO' could be adopted by a broad community of managers involved in vector control.

International audience

Unknown outside the Asian jungles almost fourty years ago, the tiger mosquito Aedes albopictus, vector of several human pathogens, is now established across the 5 continents, including in urban areas. In France, a national plan for surveillance of dengue and chikungunya is active, and some autochthonous cases of transmission have been reported recently, underlying the present risk of transmission in areas where the mosquito is present. Probably first introduced in the Rhône-Alpes area via road transport, Ae. albopictus is since 2013 considered present and active in 5 on 8 departments. For the surveillance purposes, it is now a question of identifying areas suitable for this mosquito and how these areas could be colonized. Thus, the aim of this study is to build maps of susceptibility of Ae. albopictus presence in the Rhône-Alpes area by a modelling approach combining knowledge on both the climatic and environmental determinants for establishment., Inconnu en dehors des jungles asiatiques il y a encore quarante ans, le moustique tigre Aedes albopictus, vecteur de nombreux agents pathogènes humains, s’est désormais établi sur les cinq continents, y compris en ville. En France, il fait l’objet d’un plan national de surveillance de la dengue et du chikungunya et plusieurs cas de transmission autochtones ont été reportés récemment, soulignant ainsi la réalité du risque de transmission dans les zones où ce moustique est implanté. Probablement introduit en région Rhône-Alpes via le transport routier, Ae. albopictus est considéré comme présent et actif dans cinq des huit départements depuis 2013. Il est aujourd’hui question d’identifier les zones favorables à son implantation et comment la colonisation vers ces zones pourrait se faire. Ainsi, l’objectif de notre travail est de construire des cartes de susceptibilité de présence d’Ae. albopictus en Rhône-Alpes par modélisation combinant à la fois les connaissances sur les déterminants climatiques mais aussi environnementaux de son installation.

International audience

The use of optical methods is growing in the field of solid mechanics. In particular, the stereocorrelation technique is appealing because its use is reasonably easy, it is a non intrusive method, and its spatial and temporal resolutions are usually very good. In this work, the stereocorrelation technique is utilized for different types of loading rates concerning quasi static experiments up to ultra high speed tests. This important field of application requires the development of several specific tools to obtain quantitative results (e.g., shape, displacement and strain fields). Special methods for the calibration and optical distortions corrections are implemented. A new registration method is also introduced to deal with low spatial / high temporal resolutions. To perform the spatial matching, a correction method associated with large displacement levels, based on a numerical simulation, was developed. To characterize the method, several tests are analyzed, namely, quasi static compression on a composite material, quasi static tensile test on a tantalum plate, dynamic tensile tests on aluminum alloy samples. The main high speed experiments studied herein are cylinder expansions. For this type test, a representative synthetic case is first considered to characterize the a priori performance of the technique under very difficult experimental conditions. The technique is subsequently applied to the analysis of field data. For all the applications, the reconstruction uncertainty is quantified so that the roughness of the reconstructed surface can be estimated and, thus, the necking phenomena.; Depuis un certain nombre d'années, les méthodes optiques s'imposent dans le domaine de la mesure. Plus particulièrement, la technique de stéréo-corrélation d'images est souvent utilisée en raison de sa facilité de mise en oeuvre, de son caractère non intrusif et de sa bonne resolution spatiale couplée à un suivi temporel. Dans cette thèse, nous mettons en application la technique de stéréo-corrélation pour différentes vitesses de sollicitation allant du quasi statique à la dynamique ultra-rapide, cette dernière étant appliquée dans le cadre d'expérience de détonique. Cette large gamme d'expérimentations nous impose de développer des outils spécifiques afin d'obtenir des résultats quantifiés. Ainsi, nous avons mis au point des méthodes de correction des distorsions optiques et de l'étalonnage. Nous avons également développé une nouvelle technique d'association capable de traiter des images de faible dimension. Afin d'améliorer l'association, des méthodes de correction des grands d'eplacements, basées sur l'image elle-même ou un calcul hydrodynamique prédictif, ont été élaborées. Afin de valider l'ensemble de notre approche, nous la mettons en application lors de divers essais : compression quasi statique sur un matériau composite, traction lente sur une plaque en tantale, traction rapide sur des échantillons en aluminium. Enfin, nous nous intéressons à nos applications principales de dynamique ultra-rapide : l'expansion et le relèvement de cylindre. Pour ce dernier point, un soin particulier est apporté à l'élaboration d'un cas de synthèse représentatif de nos expériences. Ceci, dans le but de caractériser les performances de notre approche dans des conditions expérimentales sévères. Dans tous les cas, nous donnons les incertitudes de reconstruction afin de quantifier au mieux la rugosité de la surface et, par conséquent, le phénomène de striction.

International audience; The purpose of the experiment described herein is the study of material deformation (here a cylinder) induced by explosives. During its expansion, the cylinder (initially 3 mm thick) is thinning until fracture appears. Some tens of microseconds before destruction, strain localizations occur and induce mechanical necking. To characterize the time of first localizations, 25 stereoscopic acquisitions at about 500,000 frames per second are used by resorting to a single ultra-high speed camera. The 3D reconstruction from stereoscopic movies is described. A special calibration procedure is followed, namely, the calibration target is imaged during the experiment itself. To characterize the performance of the present procedure, resolution and optical distortions are estimated. The principle of stereoscopic reconstruction of an object subjected to a high speed experiment is then developed. This reconstruction is achieved by using a global image correlation code that exploits random markings on the object outer surface. The spatial resolution of the estimated surface is evaluated thanks to a realistic image pair synthesis. Last, the time evolution of surface roughness is estimated. It gives access to the onset of necking.