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Diffusion du document : INRA Unité d'Economie et Sociologie rurales 4 Allée Adolphe Bobierre CS 61103 35011 Rennes cedex (FRA); Deux enquêtes menées, en 2003, auprès des visiteurs de la forêt de Bonifatu et des habitants de la région permettent d'évaluer leurs priorités quant à la protection et à l'aménagement de la forêt. La méthodologie retenue combine la méthode des programmes et l'évaluation contingente. Chaque enquête a donné lieu à un entretien approfondi afin d'informer les personnes interrogées sur les risques encourus en l'absence d'un programme de protection de la forêt. La réalisation des enquêtes a montré l'intérêt des personnes interrogées pour la gestion de la forêt et une bonne compréhension de l'exercice d'évaluation menée à partir de scénarios. Les résultats montrent une forte similitude des préférences des visiteurs et des habitants, en dépit de caractéristiques sociologiques et économiques différentes. La priorité accordée à la prévention des incendies était certes attendue. En revanche la préférence nette pour une action visant à créer une grande zone de protection de la biodiversité, sur un tiers de la superficie, et interdite au public, n'était pas envisagée. Les actions portant sur l'organisation de l'accès et l'amélioration de l'accueil sont considérées comme secondaires.

International audience

International audience; The GOLIAT project is a consortium of academics and firefighting operators and land-use planning professionals of Corsica. One goal of GOLIAT project is to provide four operational decision support tools. To reach this goal, a survey of past fires occurred in Corsica since the twentieth century beginning is made. This inventory contributes to build up a database with a web display interface easy to use as fire patterns history. A fire behavior and impact simulator prototype for vegetation fires, a geolocation tool for hot spots using UAV images, and a guide of good practices of prescribed fires in the undergrowth are building. At the same time, experimental fires are carried out to improve knowledge about high intensity fire and the experimental results were compared to the predictions provided by a complete physical 3D model, namely FireStar3D.

International audience; Table ronde animée par Jean-François Brouttier autour des innovations liées à l'alternative du service public d'enseignement supérieur : le CLES, avec 6 interventions de 180 secondes chacune :1. Blockchain et service public : ULille porte. Le CLES est prêt ! Perrine de Coëtlogon, Cheffe de projet Blockchain Education France2. 20 ans de CLES, 20 ans de publications et d’événements scientifiques. Marie-Hélène Fries, Directrice scientifique ad interim du CLES3. Le réseau NULTE : 250 universités partenaires avec CERCLES. Johann Fischer, Président honoraire de CERCLES4. Massifier : c’est fait depuis 2014 à l’ULCO en L3 et en M2. Laura Hocquez, Référente CLES Université du Littoral Côte d’Opale5. RNCP, CPF, France Compétences : le CLES est prêt à servir la FCU. Irene Bordin Dal Pont, Responsable des relations avec le monde socio-économique pour le CLES6. Washback effect : rétropositivons dans plusieurs langues ! Stéphanie Mac Gaw, Docteure ès CLES, Université de Corte

International audience; The ambition and proposal for data modeling of myths presented in this paper is to link contemporary technical affordances to some canonical projects developed in structural anthropology. To articulate the theoretical promise and innovation of this proposal, we present a discrete-event system specification modeling and simulation approach in order to perform a generative analysis and a dynamic visualization of selected narratives, aimed at validating and revitalizing the transformational and morphodynamic theory and methodology proposed by Claude Lévi-Strauss in his structural analysis of myth. After an analysis of Lévi-Strauss’s transformational methodology, we describe in detail how discrete-event system specification models are implemented and developed in the framework of a DEVSimPy software environment. The validation of the method involves a discrete-event system specification simulation based on the extension of discrete-event system specification models dedicated to provide a dynamic Google Earth visualization of the selected myth. Future work around the discrete-event system specification formalism in anthropology is described as well as future applications regarding the impact of computational models (discrete-event system specification formalism, Bayesian inferences, and object-oriented features) to new contemporary anthropological domains.

International audience; The effectiveness of a fuelbreak, created in a homogeneous grassland on a flat terrain, was studied numerically. The analysis relies on 3D numerical simulations that were performed using a detailed physical-fire-model (FIRESTAR3D) based on a multiphase formulation. To avoid border effects, calculations were carried out by imposing periodic boundary conditions along the two lateral sides of the computational domain, reproducing that way a quasi-infinitely long fire front. A total of 72 simulations were carried out for various wind speeds, fuel heights, and fuelbreak widths, which allowed to cover a large spectrum of fire behaviour, ranging from plume-dominated fires to wind-driven fires. The results were classified in three main categories: 1- “Propagation” if fire crossed the fuelbreak with a continuous fire front, 2- “Overshooting” and “Marginal” if fire marginally crosses the fuelbreak with the formation of burning pockets, and 3- “No propagation” if fire does not cross at all the fuelbreak. The ratio of fuelbreak width to fuel height, marking the “Propagation”/“No propagation” transition, was found to be scaled with Byram's convection number Nc as 75.07 × Nc−0.46. The numerical results were also compared to an operational wildfire engineering tool (DIMZAL) dedicated to fuelbreaks dimensioning.

Nous nous intéressons ici à la gouvernance d’une catégorie d’aires marines protégées, Natura 2000 en mer, et aux déterminants de l’efficacité de la gouvernance des sites. Après avoir constitué une base de données portant sur 158 sites localisés en France métropolitaine, un échantillon de 20 sites a été l’objet d’une analyse comparative par études de cas. Nous constatons d’abord qu’un même cadre standard est décliné, en réalité, de façons différentes selon les façades, régions et sites. La diversité des situations de gouvernance est déchiffrée à partir de l’identification de quatre facteurs discriminants : l’enchevêtrement (ou non) du site dans un autre dispositif de gestion territoriale, les temporalités de la gouvernance (en amont ou en aval du document d’objectifs), les proximités locales (préexistantes ou à créer), la situation géographique du site (côtier ou au large). L’analyse porte ensuite sur ce que produit la gouvernance, selon ses caractéristiques, avec différents types de plus-values (effets directs et effets-rebonds, ressources, actions et coordinations) qui ne se révèlent effectives que sous certaines conditions. Les facteurs qui fondent l’efficacité et la qualité de la gouvernance sont finalement caractérisés, au regard des objectifs du dispositif et différentes pistes d’amélioration en sont déduites., This article is focused on the governance of one type of Marine Protected Areas, namely Natura 2000 at sea. The aim is to identify what is determinant for the effectiveness of their governance. From a database of 158 sites located in Hexagonal France, 20 were used for comparative case-studies. The analysis of the database shows that despite an identical national framework, it is in fact implemented very differently according to the diversity of maritime frontage, regions and sites. To understand this diversity, we describe four discriminant factors: the overlapping of the Natura 2000 area within another territorial management zone, the governance temporalities (before or after the management plan), local proximities (pre-existing or to be created), the geographical location of the site (coastal or offshore). Then we analyze the effects and impacts of governance, according to their characteristics. Their added benefits are described (direct effect, rebound-effect, resources, actions and coordination), revealing that their effectiveness is nonetheless conditional. The effectiveness and quality of the governance are then characterized according to the objectives of Natura 2000 at sea and some improvements are suggested.

Deep groundwater circulation increases multiplicity and complexity of groundwater pathways providing a high diversity of intrinsic water properties. Water-rock interactions at depth associated with transit time disparities generate singular mineralisation with high temperature, notable dissolved ions and significant gaseous content. As shown in literature, deep processes involved in gas release can be deduced from fluid gas composition collected at the surface. Widely used as tracers in volcanic areas, seismically- and tectonically-active regions, the gaseous emission monitoring is underused to understand the regional and local groundwater flow patterns that are not linked to an active zone. In order to refine knowledge on complex flow organisation at the origin of diversified mineral springs, this study aims to experiment the use of dissolved gaseous components as a tracer of water up flows interactions.The oriental plain of Corsica (France) has been chosen for its wide variety of mineral waters (22 springs) emerging at the interface of magmatic (Hercynian orogenesis), metamorphic (Alpine orogenesis) and sedimentary rocks (from the Alpine orogenesis and from Neogene deposits). Dissolved reactive (N2, CO2, CH4, H2S, H2, O2) and noble gases (Ne, Ar, He) on 9 springs have been quarterly sampled (April, July, September & December 2018), and analysed by gas chromatography (µGC).The first results highlight 3 very contrasted gas abundances:(1) N2-rich thermal waters (54°C), poorly mineralised, with noble gas occurrence as cortege gases. This highlights the influence of deep flow with a long groundwater residence time. (2) CO2-rich cold waters (2 as cortege gase. This highlights the occurence of deep flow interacting during his upflow with carbonates of metamophosed rocks. (3) CH4-rich cold waters (2S and CO2 as cortege gases. This highlights biotic anaerobic activity involvement in gases composition of the mineral waters. Then, based on the observed abundance of noble gases, theoretical recharge conditions were computed to defined recharge temperature, air- and He-excess. Computation results have stressed out the common origin of these three gas, depending on flow paths, reservoir conditions, biotic and abiotic interaction involvement. The circulation within magmatic reservoir is responsible for the deep N2-rich flow, which shows during his up flow abiotic interactions with metamorphised carbonates rocks, increasing the CO2 content in water. Then under anoxic geological confinement in deep sedimentary layers, the CO2 is reduced into CH4 and N2 into NH4. In the shallowest sedimentary layers, CH4 formed is degraded, due to the occurrence of rich-organic matter lithology, by biotic activity into H2S.This monitoring substantially contributes to improving the complex hydrogeological model of Corsican mineral springs, highlighting the link between deep regional and local groundwater flow; whose even of the non-conventional tools doesn’t succeed in clearly testified about the deep escape mechanisms of natural fluids in this non-volcanic regions. In absence of current volcanism, seismic- or tectonic-activity, monitoring the dissolved gases releasing at the surface by thermo-mineral springs provides fundamental information about deep and complex flow paths.

International audience

This thesis proposes to study the history of the imaginary of a political community : that of the elected members of the Assembly of Corsica. Undertaking work of this type implies considering that in-depth knowledge of a human community and its history can be rich in lessons, for the said community and beyond, particularly in terms of public action. It is therefore, resolutely, an applied research approach. The "political" imaginary investigated thus takes into account, from our perspective, aspects related to cultural and identity traits, which are consubstantial to politic and public action. It is therefore the expression of this imaginary relating to identity and belonging that was mainly sought in the speeches of the elected representatives of the Assembly of Corsica. This field was chosen because it is the most representative institution of the Corsican society as a whole and the one with the greatest symbolic force. We can therefore formulate the hypothesis of a close relationship between the imaginary system here and that of the island society as a whole. This field would then be a gateway to the political imaginary of the Corsican society. This should not, however, lead us to deny the specificities of each of the imaginary systems, even if they are linked.The imaginary which is therefore, more precisely, the object of our study is expressed in a precise framework: that of a deliberative institution. Within this "institution of speech" , the 2010 to 2015 term of office is the source of our main corpus. To be able to apprehend this imaginary rooted in immediate history requires, for the researcher, to know the different dimensions of this institution in its structural as well as interactional aspects. This is how we have approached the Assembly of Corsica and its imaginary : from both a structural and interactional point of view, considering them as the fruit of a history, a context, and situations of interactions. We have therefore carried out our study in a synchronic but also diachronic way, taking into account in particular its historical anchoring. In order to explore this imaginary, we tried to answer the following questions : what is this political imaginary of "identity and belonging" ? How does it appear in the hemicycle ? What are its consequences and how can it be seen as a resource for public action ?, Cette thèse se propose d’étudier l’histoire de l’imaginaire politique d’une communauté d’élus : ceux de l’Assemblée de Corse. Entreprendre un travail de ce type suppose de considérer que la connaissance approfondie d’une collectivité humaine peut être riche d’enseignements, pour ladite communauté et au-delà, notamment en matière d’action publique. Il s’agit donc, résolument, d’une démarche de recherche appliquée. L’imaginaire « politique » investigué prend donc en compte, dans la perspective qui est la nôtre, les aspects relatifs aux traits culturels et identitaires, ceux-ci étant consubstantiels au politique et à l’action publique. C’est donc l’expression de cet imaginaire relatif à l’identité et à l’appartenance qui a été principalement recherchée au sein de la parole des élus de l’Assemblée de Corse. Ce terrain a été choisi car il s’agit de l’institution la plus représentative de l’ensemble de la société corse et celle qui est dotée de la force symbolique la plus considérable. Nous pouvons donc formuler l’hypothèse d’une relation étroite entre le système imaginaire en présence et celui de la société insulaire dans son ensemble. Ce terrain constituerait, alors, une porte d’entrée vers l’imaginaire politique de la société corse. Cela ne doit cependant pas nous conduire à nier les spécificités de chacun des deux systèmes imaginaires, même si ceux-ci connaissent d’importantes interrelations.L’imaginaire qui est donc, plus précisément, l’objet de notre étude s’exprime dans un cadre précis : celui d’une institution délibérative. Au sein de cette « institution de parole », la mandature 2010-2015 est la source de notre corpus principal. Pouvoir appréhender cet imaginaire enraciné dans l’histoire immédiate nécessite, pour le chercheur, de connaître les différentes dimensions de cette institution dans ses aspects structurels comme interactionnels. C’est ainsi que nous avons abordé l’Assemblée de Corse et son imaginaire : tant d’un point de vue structurel qu’interactionnel, en les considérant comme le fruit d’une histoire, d’un contexte, et de situations d’interactions. Nous avons donc adopté une approche synchronique mais également diachronique, en prenant particulièrement en compte l’ancrage historique de l’objet d’étude. Pour explorer l’imaginaire en question, nous avons tenté de répondre aux interrogations suivantes : quel est cet imaginaire politique « de l’identité et de l’appartenance » ? Comment apparaît-il au sein de l’hémicycle ? Quelles sont ses conséquences et comment peut-on l’envisager comme une ressource en matière d’action publique ?

R-spondin2 (RSPO2) is a member of the R-spondin family, which are secreted activators of the WNT/β-catenin (CTNNB1) signaling pathway. In the mouse postnatal ovary, WNT/CTNNB1 signaling is active in the oocyte and in the neighboring supporting cells, the granulosa cells. Although the role of Rspo2 has been previously studied using in vitro experiments, the results are conflicting and the in vivo ovarian function of Rspo2 remains unclear. In the present study, we found that RSPO2/Rspo2 expression is restricted to the oocyte of developing follicles in both human and mouse ovaries from the beginning of the follicular growth. In mice, genetic deletion of Rspo2 does not impair oocyte growth, but instead prevents cell cycle progression of neighboring granulosa cells, thus resulting in an arrest of follicular growth. We further show this cell cycle arrest to be independent of growth promoting GDF9 signaling, but rather associated with a downregulation of WNT/CTNNB1 signaling in granulosa cells. To confirm the contribution of WNT/CTNNB1 signaling in granulosa cell proliferation, we induced cell type specific deletion of Ctnnb1 postnatally. Strikingly, follicles lacking Ctnnb1 failed to develop beyond the primary stage. These results show that RSPO2 acts in a paracrine manner to sustain granulosa cell proliferation in early developing follicles. Taken together, our data demonstrate that the activation of WNT/CTNNB1 signaling by RSPO2 is essential for oocyte-granulosa cell interactions that drive maturation of the ovarian follicles and eventually female fertility.

Xylem resistance to cavitation is a key parameter in drought resistance of trees. Indeed, water stress tolerant species are less vulnerable to cavitation than water stress intolerant species. At the within species level, phenotypic variability was reported for the xylem cavitation resistance, mainly based on plasticity among environmental growth conditions. This raises the question of genetic and structural determinants of this plasticity. The objective of the present work is to identify the structural determinants controlling plasticity of xylem resistance to cavitation. Young poplars trees were grown in contrasted water availability or light exposure in order to induce acclimation in hydraulic properties. We then characterized the structural modifications of their acclimated xylem at three levels: xylem organization, vessels dimensions and pits shape. We used different microscopy techniques including Transmission Electron Microscope (T.E.M.), Scanning Electron Microscope (M.E.B.) and Light Microscope – on the same individual trees. We specially investigated the intervessel pits that provide hydraulic connections between vessels while they prevent air embolism spreading. Moreover, a local approach using direct observation of embolism spreading at the cellular level via X-ray micro-CT allowed us to explore the structural determinants of vessel resistance to cavitation.

International audience; Posidonia oceanicareefs along the French Mediterranean coast were inventoried and mapped using bibliographical data, analysis of aerial photos, images obtained using drone and 3D models. Sixteen previously unreported reefs and another 13 reefs that had been destroyed or disappeared were identified. In all, 75 Posidonia reef structures have were known to exist but today there are only 62 left.

International audience; Quand de si nombreuses personnalités réputées et expertes dans leur métier se rejoignent pour contribuer à la rédaction d’un ouvrage, nul ne doute qu’un motif puissant les y incite. La raison en est ici de rendre un hommage à un collègue et ami.Le titre de cet ouvrage, une sorte d’oxymore, résume en une expression toute l’originalité positive qui marque l’engagement profond de Michel Kalika : celui de faire bouger les lignes au sein de la sphère académique en lui insufflant l’énergie de l’entrepreneuriat, en apportant dans le monde des universités et des grandes écoles les vertus du dynamisme de l’entrepreneur.Une carrière universitaire lorsqu’elle est mue par le souhait régulier de changement et par un indéfectible désir de prendre des initiatives comporte à l’évidence des facettes multiples. Ce sont des lieux et on retrouve ici Angers, Poitiers et Tours, Paris, Strasbourg, Lyon et naturellement le monde entier avec un sérieux enracinement récent à Bruxelles et au Luxembourg. Ce sont des thématiques qui vont de l’organisation au numérique en passant par les systèmes d’information et la stratégie. Ce sont des réseaux qui s’alignent du national à l’international, de la recherche à l’entreprise, du professionnel à l’amitié. Ce sont des institutions qui se profilent des universités aux écoles et des associations aux fondations.Les contributions ont été regroupées autour de trois parties. D’abord, le professeur / chercheur qui a produit un grand nombre d’articles et de communications reconnues et a engendré des thèses en nouant avec ses doctorants de forts liens d’estime et de considération réciproque. Ensuite, l’administrateur repéré par les multiples programmes, diplômes, centres, établissements qui ont été créés, animés, développés. Enfin, l’entrepreneur qui a le talent de découvrir une opportunité d’affaires et sait la faire évoluer au gré des contextes en adoptant ainsi les principes de l’effectuation.

This thesis fits in the context of the protection against wildfire risks. The main goal is the characterization of smoke and the definition of source terms and ignition criterions, available for modelization, to improve decision support tools for fire risk management. The second objective deals with the impact of smoke exposure on human health.Flammability of vegetation fuel was studied at laboratory scale using two calorimeters (cone and Large Scale Heat Release), for two species: Cistus monspeliensis and Pteridium aquilinum. The study of ignition properties and combustion dynamics of plants showed the influence of their thickness and structure on ignition time, ignition temperature and on heat release. A limit size of fuel particles for burning behavior was defined as well as an ignition criterion independent of fuel thickness and structure.Characterization of smoke was carried out at laboratory scale (cone and LSHR) and ground scale (prescribed burns). It highlights the importance of combustion phases for smoke composition, especially for aerosols. Large quantities of tars are released during the pre-ignition phase while soot are released in flaming phase. Emission factors of effluents characteristic of Mediterranean vegetation were obtained, that can be used in fire/atmosphere modelling. This study also emphasizes the scale effect on smoke production and composition.During ground fires, the characterization was conducted at two locations (in the smoke plume and in firefighters working atmosphere). The analysis of firefighters working atmosphere in prescribed burning conditions and the following of smoke exposure biomarkers (in exhaled breath and urines) showed an overexposure to toxic compounds (irritating, asphyxiating and CMR: carcinogenic, mutagenic and reprotoxic). Recommendations on prescribed burning practices (period, timetable, atmospheric conditions, positioning) were provided in order to attempt reducing the smoke exposure.; Ce travail de thèse s’inscrit dans le contexte de la protection contre les risques incendies de végétation. L’objectif principal est la caractérisation des fumées et la définition de termes sources et de critères d’inflammation utilisables en modélisation, à des fins d’améliorations des outils d’aides à la décision pour la gestion des risques incendies. Le second objectif est l’observation de l’impact de l’exposition aux fumées sur la santé humaine.La réaction au feu de deux combustibles végétaux, Cistus monspeliensis et Pteridium aquilinum, a été étudiée en laboratoire à l’échelle du cône calorimètre et du LSHR (Large Scale Heat Release). L’étude des propriétés d’inflammation et de la dynamique de combustion des végétaux a montré l’influence de leur épaisseur et de leur structure sur le temps et la température d’ignition ainsi que sur l’énergie libérée. Elle a permis de définir une taille limite des particules végétales relative à un changement de comportement au feu ainsi qu’un critère d’inflammation indépendant de l’épaisseur et de la structure du combustible.La caractérisation des fumées a été réalisée en laboratoire (cône calorimètre et LSHR) et sur le terrain (brûlages dirigés). Elle a mis en exergue l’importance de la phase de combustion pour la composition des émissions, notamment pour les aérosols. D’importantes quantités de goudrons sont émises durant la phase de pré-ignition tandis que les suies sont émises lors de la phase de flamme. Elle a notamment permis le calcul de facteurs d’émission des effluents propres à la végétation méditerranéenne, utilisables dans les modèles de simulation couplés feu/atmosphère. Cette étude a également souligné l’effet d’échelle sur la production et la composition des fumées.Sur les feux de terrain, cette caractérisation a été effectuée à deux niveaux (dans le panache de fumées et dans l’atmosphère de travail des opérationnels). L’analyse de l’atmosphère de travail des opérationnels en conditions de brûlages dirigés et le suivi de biomarqueurs d’exposition aux fumées ont révélés une surexposition à des composés toxiques (irritants, asphyxiants et CMR : cancérogènes, mutagènes et reprotoxiques) susceptible d’induire des effets sur la santé. Des recommandations sur les pratiques de brûlages dirigés (période, horaires, conditions atmosphériques, positionnement) ont alors été apportées dans ce travail, en vue de réduire l’exposition aux fumées.

This thesis fits in the context of the protection against wildfire risks. The main goal is the characterization of smoke and the definition of source terms and ignition criterions, available for modelization, to improve decision support tools for fire risk management. The second objective deals with the impact of smoke exposure on human health.Flammability of vegetation fuel was studied at laboratory scale using two calorimeters (cone and Large Scale Heat Release), for two species: Cistus monspeliensis and Pteridium aquilinum. The study of ignition properties and combustion dynamics of plants showed the influence of their thickness and structure on ignition time, ignition temperature and on heat release. A limit size of fuel particles for burning behavior was defined as well as an ignition criterion independent of fuel thickness and structure.Characterization of smoke was carried out at laboratory scale (cone and LSHR) and ground scale (prescribed burns). It highlights the importance of combustion phases for smoke composition, especially for aerosols. Large quantities of tars are released during the pre-ignition phase while soot are released in flaming phase. Emission factors of effluents characteristic of Mediterranean vegetation were obtained, that can be used in fire/atmosphere modelling. This study also emphasizes the scale effect on smoke production and composition.During ground fires, the characterization was conducted at two locations (in the smoke plume and in firefighters working atmosphere). The analysis of firefighters working atmosphere in prescribed burning conditions and the following of smoke exposure biomarkers (in exhaled breath and urines) showed an overexposure to toxic compounds (irritating, asphyxiating and CMR: carcinogenic, mutagenic and reprotoxic). Recommendations on prescribed burning practices (period, timetable, atmospheric conditions, positioning) were provided in order to attempt reducing the smoke exposure., Ce travail de thèse s’inscrit dans le contexte de la protection contre les risques incendies de végétation. L’objectif principal est la caractérisation des fumées et la définition de termes sources et de critères d’inflammation utilisables en modélisation, à des fins d’améliorations des outils d’aides à la décision pour la gestion des risques incendies. Le second objectif est l’observation de l’impact de l’exposition aux fumées sur la santé humaine.La réaction au feu de deux combustibles végétaux, Cistus monspeliensis et Pteridium aquilinum, a été étudiée en laboratoire à l’échelle du cône calorimètre et du LSHR (Large Scale Heat Release). L’étude des propriétés d’inflammation et de la dynamique de combustion des végétaux a montré l’influence de leur épaisseur et de leur structure sur le temps et la température d’ignition ainsi que sur l’énergie libérée. Elle a permis de définir une taille limite des particules végétales relative à un changement de comportement au feu ainsi qu’un critère d’inflammation indépendant de l’épaisseur et de la structure du combustible.La caractérisation des fumées a été réalisée en laboratoire (cône calorimètre et LSHR) et sur le terrain (brûlages dirigés). Elle a mis en exergue l’importance de la phase de combustion pour la composition des émissions, notamment pour les aérosols. D’importantes quantités de goudrons sont émises durant la phase de pré-ignition tandis que les suies sont émises lors de la phase de flamme. Elle a notamment permis le calcul de facteurs d’émission des effluents propres à la végétation méditerranéenne, utilisables dans les modèles de simulation couplés feu/atmosphère. Cette étude a également souligné l’effet d’échelle sur la production et la composition des fumées.Sur les feux de terrain, cette caractérisation a été effectuée à deux niveaux (dans le panache de fumées et dans l’atmosphère de travail des opérationnels). L’analyse de l’atmosphère de travail des opérationnels en conditions de brûlages dirigés et le suivi de biomarqueurs d’exposition aux fumées ont révélés une surexposition à des composés toxiques (irritants, asphyxiants et CMR : cancérogènes, mutagènes et reprotoxiques) susceptible d’induire des effets sur la santé. Des recommandations sur les pratiques de brûlages dirigés (période, horaires, conditions atmosphériques, positionnement) ont alors été apportées dans ce travail, en vue de réduire l’exposition aux fumées.

International audience; Wildlife species as reservoirs of infectious pathogens represent a serious constraint in the implementation of disease management strategies. In the Mediterranean island of Corsica, the dynamics of hepatitis E virus (HEV) and Aujeszky's disease virus (ADV) are suspected to be influenced by interactions between wild and domestic pigs. To improve our understanding of these influences, we first compared the seroprevalences of both viruses in domestic pig populations from different locations with contrasted levels of wild-domestic interactions, ADV vaccination, biosafety, and farm husbandry. Second, we performed an analysis at a more restricted geographical scale, to assess the matching of ADV or HEV prevalence between sympatric wild boar and outdoor pig farms most exposed to interactions with wildlife. Logistic models were adjusted to the observed data. A high seroprevalence of HEV (>80%) and ADV (40%) in pigs, with no significant difference according to the region, confirms that both pathogens are enzootic in Corsica. Vaccination against ADV had a strong protective effect, even when performed voluntarily by farmers. Farm biosafety had an additional effect on pigs' exposure, suggesting that contact between wild boars and pigs were involved in disease transmission. A strong correlation in HEV seroprevalence was observed between pigs and wild boars that were in close contact, and significantly lower seroprevalence was observed in pigs when they had little contact with wild boars due to spatial segregation. These results suggest a regular HEV circulation between sympatric wild boar and domestic pigs. The high HEV seroprevalence observed in domestic pigs (>80%) suggests a spillover of the virus from domestic to wild populations through environmental contamination, but this hypothesis has to be confirmed. Conversely, even though avoiding sows' release on pasture during estrus showed some protecting effect in the free ranging pig farms regarding ADV, ADV seroprevalence was not dependent on the swine populations (wild or domestic) or on the wild-domestic spatial overlap, suggesting two quasi-separate enzootic cycles. This information will prove useful for designing more efficient disease management strategies in Corsica and similar contexts.

Respiratory syncytial virus (RSV) is considered the major pathogen causing severe lower respiratory tract infections among infants and young children [1]. RSV is the most common cause of hospitalisation for acute lower respiratory tract infection in children younger than 5 years and is estimated to cause between 66,000 and 199,000 deaths worldwide every year [2]. Its significance in causing substantial morbidity and hospitalisation in the first year of life has been affirmed in a recent study and a meta-analysis [3,4]. In England, average annual hospital admission rates are 35.1 per 1,000 children younger than 1 year and 5.31 per 1,000 children aged 1–4 years [5]. In addition to children, RSV causes a substantial disease burden in elderly people and patients with chronic obstructive pulmonary disease [6,7]. RSV causes seasonal epidemics worldwide [8], with one to two epidemics each year [9] following latitudinal gradients in timing, duration, seasonal amplitude and between-year variability [8,9]. In some studies, the seasonal periodicity has been connected to climatic factors [9-11], but a common factor that explains all observed periodicity has not been established. Meteorological conditions such as temperature and high relative humidity have been reported as important predictors of RSV epidemics [9,12]. In the United States (US) and Japan, annual national and regional variation of RSV season onset and end has been reported [13-15]. In the Nordic countries, a major outbreak often alternates with a minor one, with the minor peak in the spring and a major one the following winter [16-19], a phenomenon reported also in Croatia [20], Denmark [21] and Germany [22]. RSV antigenic groups A and B alternate in two-year cycles in Finland, with dominance of the group A viruses in years 1981–82, 1985–86 and 1989–90 and the group B viruses 1983–84 and 1987–88 [17,19], and different genotypes dominate the circulation in consecutive epidemics in Korea [23]. In Spain, no biennial rhythm has been detected but rather a stable annual epidemic with a peak between week 52 and week 1 and circulation 2–8 weeks earlier than influenza viruses [24]. Similarly, in the United Kingdom (UK), one stable epidemic per year is observed [5]. Immunoprophylaxis to prevent RSV infection with a neutralising monoclonal antibody, palivizumab, has been developed for administration to target groups on a monthly basis during the RSV season [25]. However, this drug is limited to high-risk infants, the cost prohibits its use in low- and middle-income countries and the data on effectiveness of the drug in children at high risk other than infants born at gestational age

The MAP sector (Medicinal and Aromatic Plants) is a booming sector. The demand for essential oil is constantly increasing, and in addition to the historical purchasers such perfumers, there is an increasing demand from the general public, especially since the advent of the "organic" trend. Their fields of application are multiple, from aromatherapy to cosmetics or perfumery or agri-food. In this context, this work had two main objectives. Initially, the study of the essential oils of several coniferous species introduced in Corsica (Larix decidua, Pseudotsuga menziesii, Pinus ponderosa, Sequoiadendron giganteum, Cryptomeria japonica and Calocedrus decurrens), which could contribute to a broader range of the essential oils produced on the island. In the second phase, we focused on the essential oils of various endemic species to Madagascar (Melicope belahe, Vepris unifoliolata, Cinnamosma madagascariensis and Elionurus tristis), which are widely used in traditional medicine. Analysis of all essential oils was carried out by combination of GC(RI), GC-MS and 13C-NMR.The first part of this thesis concerns the analysis of the oils of six coniferous species introduced in Corsica. Among them, the oils of L. decidua, P. menziesii, P. ponderosa, S. giganteum and C. japonica are dominated by a high content of monoterpenes. Those of L. decidua, P. menziesii and C. japonica also contain a few sesqui- and diterpenes at appreciable contents, while those of P. ponderosa and S. giganteum are rich in phenylpropanoids. On the other hand, C. decurrens oils are more complex and required several fractionation steps to identify four unknown molecules in our databases: pin-2-en-8-ol, pin-2-en-8-yl acetate, methyl pin-2-en-8-oate, and pin-2-en-8-al. The last two are new molecules.The second part was devoted to the analysis of the essential oils of endemic Madagascar species. The leaves essential oil of M. belahe led to the identification of 56 constituents, majors of which are: α-pinene (42.6%), linalool (6.2%), (E)-β-caryophyllene (5.2%) and β-elemene (4.4%). V. unifoliolata exhibited a bark essential oil with high amounts of thermosensitive molecules: isofuranodiene (43.9%), germacrone (17.1%), curzerene (9.6%) and germacrene B (5.3%). 13C-NMR allowed the identification and quantification of these compounds. In addition to β-pinene (49.9%) and α-pinene (19.5%) as major constituents, the bark oil of C. madagascariensis contains cyclolocopacamphene (2.0%), an epimer of cyclosativene. We report for the first time its 13C-NMR chemical shifts. The essential oils of E. tristis are characterized by great chemical complexity. We have identified several oxygenated sesquiterpenes that are rarely encountered and four unknown compounds: (i) 7-epi-khusian-2-ol and 4,8-di-epi-acorone (respectively two new epimers of khusian-2-ol and acorone); (ii) 2-epi-ziza-5-en-2-ol; and (iii) elionurone, which is so far the one and only molecule with the new terpenic skeleton that we have named elionurane. We suggest a biosynthesis pathway for this molecule, which seems to be directly linked to that of the zizaane skeleton.; Le secteur des PAM (Plantes Aromatiques et Médicinales) est un secteur en plein essor. La demande en huile essentielle est en constante augmentation, au-delà des acheteurs historiques que sont les parfumeurs, il y a une demande toujours plus grande de la part du grand public, notamment depuis l’avènement de la tendance « bio ». Leurs domaines d’applications sont multiples, de l’aromathérapie à la cosmétique en passant par la parfumerie ou encore l’agroalimentaire. Dans ce contexte, ce travail présentait deux objectifs principaux. Dans un premier temps il s’agissait d’étudier les huiles essentielles de plusieurs espèces de conifères introduites en Corse (Larix decidua, Pseudotsuga menziesii, Pinus ponderosa, Sequoiadendron giganteum, Cryptomeria japonica et Calocedrus decurrens) qui pourraient contribuer à un élargissement de la gamme des huiles essentielles produites sur l’île. Et dans un second temps, nous nous sommes intéressés aux huiles essentielles de diverses espèces endémiques de Madagascar (Melicope belahe, Vepris unifoliolata, Cinnamosma madagascariensis et Elionurus tristis) très utilisées en médecine traditionnelle. L’analyse de toutes ces huiles essentielles ont été menées par combinaison de la CPG(Ir), CPG-SM et RMN 13C.La première partie de cette thèse concerne l’analyse des huiles des six espèces de conifères introduites en Corse. Parmi elles, les huiles de L. decidua, P. menziesii, P. ponderosa, S. giganteum et C. japonica qui sont dominées par une forte teneur en monoterpènes. Celles de L. decidua, P. menziesii et C. japonica contiennent également à des teneurs non négligeables quelques sesqui- et diterpènes, alors que celles de P. ponderosa et S. giganteum sont riches en phénylpropanoïdes. En revanche, les huiles de C. decurrens, plus complexes ont nécessité plusieurs étapes de fractionnement afin d’identifier quatre molécules inconnues de nos banques de données : le pin-2-èn-8-ol, l’acétate de pin-2-èn-8-yle, le pin-2-èn-8-oate de méthyle, et le pin-2-èn-8-al. Les deux dernières étant des molécules nouvelles.La seconde partie fut consacrée à l’analyse des huiles essentielles d’espèces endémiques de Madagascar. L’huile essentielle de feuilles de M. belahe a conduit à l’identification de 56 constituants dont les majoritaires sont : l’α-pinène (42,6%), le linalol (6,2%), l’(E)-β-caryophyllène (5,2%) et le β-élemène (4,4%). V. unifoliolata présentait une huile essentielle d’écorces avec une teneur importante en molécules thermosensibles : isofuranodiène (43,9%), germacrone (17,1%), curzerène (9,6%) ou encore germacrène B (5,3%). La RMN 13C a permis de réaliser l’identification et la quantification de ces composés. Outre le β-pinène (49,9%) et l’α-pinene (19.5%) comme constituants majoritaires, l’huile d’écorces de C. madagascariensis contient le cyclocopacamphène (2,0%), qui est un épimère du cyclosativène. Nous reportons pour la première fois ses déplacements chimiques de RMN 13C. Les huiles essentielles d’E. tristis sont caractérisées par une grande complexité chimique. Nous avons identifié plusieurs sesquiterpènes oxygénés, peu fréquemment rencontrés et quatre composés inconnus : (i) le 7-épi-khusian-2-ol et la 4,8-di-épi-acorone (respectivement deux nouveaux épimères du khusian-2-ol et de l’acorone) ; (ii) le 2-épi-ziza-5-èn-2-ol ; et (iii) l’élionurone qui est à ce jour la seule et unique molécule présentant un nouveau squelette terpénique que nous avons nommé élionurane. Nous proposons d’ailleurs une voie de biosynthèse de cette molécule, qui semble directement liée à celle du squelette zizaane.

In 2012, the European Commission announced the conclusion of a study performed par the ScientificCommittee on Consumer Safety (SCCS), which proposed to extend the list of the 26 suspected fragrancesallergens to 82 ingredients of which chemically defined substances and extracts. Waiting for the official voteof the European Commission, the perfume industry tackled this challenge and is currently developing a methodenabling the quantification of the chemically defined substances present in both natural raw ingredients andfragrance compositions.Two main difficulties are associated to the dosage of these suspected fragrance allergens: the number ofanalytes and the complexity of the matrix itself. The targeted limit allowed for each substance (10ppm) requiresa methodology associating selectivity and quantitative performances.Different GC-MS methods are presented and discussed in this report. All are based on internal standardizationmethodology. Each of them differs in terms of detection mode and by the number of runs for achievingsatisfactory performance goals.The best analytical methodologies are validated by their accuracy profiles and enabled, depending on thematrix complexity, to quantify more than two third of the substances with a recovery rate between 70 and130%:‐ one was performed by running analyses in SIM/Scan mode on three different stationary phases (polar,intermediate, and non-polar);‐ the second by running two analyses in MRM mode on orthogonal stationary phases.A third analytical strategy was tested using Q-TOF MS in high resolution. The quality of the results was judgedunsatisfactory for the time being.The two methodologies proposed either in SIM/scan or in MRM modes present advantages and drawbacks.They allow meeting customer expectations. The SIM/scan strategy is identified as the optimal solution forstudying unknown samples. On the other hand, the MRM strategy seems more dedicated for investigatingsamples of which composition is known.Methods developed for the dosage of suspected fragrances allergens must be simple and efficient for beingused on a daily basis by QC laboratories. The analytical strategy presented in this work fulfills these criteria; La Commission européenne a rendu publique en 2012 les conclusions d’une étude réalisée par son comitéscientifique pour la sécurité du consommateur proposant l’étendre l’actuelle liste de 26 substances suspectéesallergisantes dans les produits cosmétiques à 82 références étiquetables composées de molécules chimiquementdéfinies et d’extraits naturels. Dans l’attente d’une décision du législateur sur ce sujet, l’industrie de laparfumerie doit envisager une solution analytique permettant de répondre à cette problématique en quantifiantdans les extraits aromatiques naturels et dans les compositions parfumantes près d’une soixantaine decomposés potentiellement allergisants.Le dosage des molécules suspectées allergisantes représente une difficulté majeure tant par le nombred’analytes que par la complexité des matrices à étudier. Le seuil de quantification de chaque substance fixé à10ppm par la profession nécessite une solution analytique alliant sélectivité et performances quantitatives.Plusieurs méthodes développées en chromatographie gazeuse couplée à la spectrométrie de masse sontprésentées et discutées dans ce rapport. Chacune repose sur une quantification par étalonnage interne maisdiffère par le mode de détection employé et par le nombre d’analyses nécessaire pour atteindre des objectifsde performance satisfaisants.Deux propositions analytiques jugées pertinentes sont validées par le profil d’exactitude et permettent dequantifier, en fonction de la complexité de la matrice analysée, plus des deux tiers des composés avec des tauxde recouvrement compris entre 70 et 130% :- la première consiste à réaliser trois analyses en mode SIM/Scan sur des colonnes capillaires de polaritédifférente (polaire, apolaire et de polarité moyenne) ;- la seconde repose sur deux analyses en mode MRM effectuées sur des colonnes capillaires de polaritéorthogonale.Une troisième stratégie analytique en haute résolution a été initiée avec un analyseur hybride Q-TOF sanstoutefois parvenir à des résultats satisfaisant.Les méthodes proposées en mode SIM/Scan et en mode MRM présentent chacune des avantages et desinconvénients et permettent de répondre aux attentes des clients. La stratégie SIM/Scan est identifiée commel’outil le plus à même d’étudier les échantillons inconnus alors que celle développée en mode MRM s’avèrepertinente pour mener des investigations sur les matrices de composition connue.Les méthodes de dosage des substances suspectées allergisantes développées pour l’industrie de la parfumeriedoivent être simples et efficaces afin de répondre aux besoins des laboratoires de contrôle qualité. Les stratégiesanalytiques proposées dans ce mémoire satisfont ces critères.

In 2012, the European Commission announced the conclusion of a study performed par the ScientificCommittee on Consumer Safety (SCCS), which proposed to extend the list of the 26 suspected fragrancesallergens to 82 ingredients of which chemically defined substances and extracts. Waiting for the official voteof the European Commission, the perfume industry tackled this challenge and is currently developing a methodenabling the quantification of the chemically defined substances present in both natural raw ingredients andfragrance compositions.Two main difficulties are associated to the dosage of these suspected fragrance allergens: the number ofanalytes and the complexity of the matrix itself. The targeted limit allowed for each substance (10ppm) requiresa methodology associating selectivity and quantitative performances.Different GC-MS methods are presented and discussed in this report. All are based on internal standardizationmethodology. Each of them differs in terms of detection mode and by the number of runs for achievingsatisfactory performance goals.The best analytical methodologies are validated by their accuracy profiles and enabled, depending on thematrix complexity, to quantify more than two third of the substances with a recovery rate between 70 and130%:‐ one was performed by running analyses in SIM/Scan mode on three different stationary phases (polar,intermediate, and non-polar);‐ the second by running two analyses in MRM mode on orthogonal stationary phases.A third analytical strategy was tested using Q-TOF MS in high resolution. The quality of the results was judgedunsatisfactory for the time being.The two methodologies proposed either in SIM/scan or in MRM modes present advantages and drawbacks.They allow meeting customer expectations. The SIM/scan strategy is identified as the optimal solution forstudying unknown samples. On the other hand, the MRM strategy seems more dedicated for investigatingsamples of which composition is known.Methods developed for the dosage of suspected fragrances allergens must be simple and efficient for beingused on a daily basis by QC laboratories. The analytical strategy presented in this work fulfills these criteria, La Commission européenne a rendu publique en 2012 les conclusions d’une étude réalisée par son comitéscientifique pour la sécurité du consommateur proposant l’étendre l’actuelle liste de 26 substances suspectéesallergisantes dans les produits cosmétiques à 82 références étiquetables composées de molécules chimiquementdéfinies et d’extraits naturels. Dans l’attente d’une décision du législateur sur ce sujet, l’industrie de laparfumerie doit envisager une solution analytique permettant de répondre à cette problématique en quantifiantdans les extraits aromatiques naturels et dans les compositions parfumantes près d’une soixantaine decomposés potentiellement allergisants.Le dosage des molécules suspectées allergisantes représente une difficulté majeure tant par le nombred’analytes que par la complexité des matrices à étudier. Le seuil de quantification de chaque substance fixé à10ppm par la profession nécessite une solution analytique alliant sélectivité et performances quantitatives.Plusieurs méthodes développées en chromatographie gazeuse couplée à la spectrométrie de masse sontprésentées et discutées dans ce rapport. Chacune repose sur une quantification par étalonnage interne maisdiffère par le mode de détection employé et par le nombre d’analyses nécessaire pour atteindre des objectifsde performance satisfaisants.Deux propositions analytiques jugées pertinentes sont validées par le profil d’exactitude et permettent dequantifier, en fonction de la complexité de la matrice analysée, plus des deux tiers des composés avec des tauxde recouvrement compris entre 70 et 130% :- la première consiste à réaliser trois analyses en mode SIM/Scan sur des colonnes capillaires de polaritédifférente (polaire, apolaire et de polarité moyenne) ;- la seconde repose sur deux analyses en mode MRM effectuées sur des colonnes capillaires de polaritéorthogonale.Une troisième stratégie analytique en haute résolution a été initiée avec un analyseur hybride Q-TOF sanstoutefois parvenir à des résultats satisfaisant.Les méthodes proposées en mode SIM/Scan et en mode MRM présentent chacune des avantages et desinconvénients et permettent de répondre aux attentes des clients. La stratégie SIM/Scan est identifiée commel’outil le plus à même d’étudier les échantillons inconnus alors que celle développée en mode MRM s’avèrepertinente pour mener des investigations sur les matrices de composition connue.Les méthodes de dosage des substances suspectées allergisantes développées pour l’industrie de la parfumeriedoivent être simples et efficaces afin de répondre aux besoins des laboratoires de contrôle qualité. Les stratégiesanalytiques proposées dans ce mémoire satisfont ces critères.

Leaf and root essential oils of two closely related but ecologically distant Philodendron species were extracted in natural conditions in French Guiana and analysed by GC/MS to i) describe the blends of volatile organic compounds (VOCs) produced by those species and ii) analyse species and environment-based variations in extracts composition. A total of 135 VOCs were detected with a majority of aliphatic sesquiterpenes. P. fragrantissimum produced mainly β-bisabolene (on average 29.12% of the extract) as well as α- and β-selinene (14.52% and 17.50%, respectively) while in P. melinonii, four aliphatic sesquiterpenes could alternatively be the main component: (E)-β-farnesene (up to 91.42% of the extract), germacrene-D (73.74%), β-caryophyllene (51.63%) and trans-α-bergamotene (41.26%). A significant effect of species and organs on extracts composition was observed while the environment (sun exposure) only affected the relative proportions of monoterpenes and sesquiterpenes in roots of P. melinonii. These results are discussed in the light of the potential role of leaf and root terpenes in Philodendron species.

Citation suggérée : Anses. (2022). Analyse des risques pour la santé humaine et animale liés aux tiques du genreHyalomma en France. (Saisine 2020-SA-0039). Maisons-Alfort : Anses, 300 p.; Les populations de tiques du genre Hyalomma sont considérées en augmentation sur unepartie de leur aire de répartition, qui semble s'étendre en Europe depuis la fin du XXe siècle.La tique Hyalomma marginatum est présente en Corse depuis plusieurs décennies (Grech-Angelini et al. 2016). Hyalomma marginatum est considérée comme une espèce de tique invasive en France continentale, de récentes publications confirmant son installation sur le littoral méditerranéen (Vial et al. 2016; Stachurski et Vial 2018; Bahet al. 2022). D’autres espèces de Hyalomma sont également présentes en France, H. scupense en Corse (Grech-Angelini , 2016) et sur le continent (Vial et Stachurski, comm. pers.), et des données récentes montrent que H. lusitanicum serait également installée en France continentale (Stachurski, comm. pers.).Cette évolution est préoccupante, car ces tiques sont vectrices de nombreux agents pathogènes responsables de maladies pour l’être humain (notamment du virus de la fièvre hémorragique de Crimée-Congo – FHCC – ou de Rickettsies) et de maladies animales (notamment Babesia caballi responsable de la piroplasmose équine).Le virus de la FHCC (CCHFV) est responsable, chez l’être humain, de flambées de fièvre hémorragique sévère, dont le taux de létalité varie de 5 à près de 30 % (Spengler, Bergeron,et Spiropoulou 2019). Une séroprévalence du CCHFV de l’ordre de 10 % aurait récemment été mise en évidence chez les ruminants domestiques en Corse, sans qu’aucun cas humain n’ait encore été observé (Grech-Angelini et al. 2020). En 2016, deux cas autochtones de FHCC ont été confirmés à Madrid (Negredo et al. 2017), pour la première fois en Europe de l’Ouest.Une étude rétrospective, menée en 2020, a montré qu'un cas de FHCC était survenu dans la même province en 2013 (Negredo et al 2021). Depuis, des cas de FHCC, dont certains mortels, sont rapportés quasiment tous les ans en Espagne (2018, 2020, 2021, 2022). De plus, la circulation du virus est en recrudescence dans la région des Balkans et en Turquie.Aussi, l’Anses s’est autosaisie le 4 mars 2020 pour analyser les risques pour la santé humaineet animale liés aux tiques du genre Hyalomma en France.

DEUG

International audience; Chemoreceptors are usually transmembrane proteins dedicated to the detection of compound gradients or signals in the surroundings of a bacterium. After detection, they modulate the activation of CheA-CheY, the core of the chemotactic pathway, to allow cells to move upwards or downwards depending on whether the signal is an attractant or a repellent, respectively. Environmental bacteria such as Shewanella oneidensis harbour dozens of chemoreceptors or MCPs (methyl-accepting chemotaxis proteins). A recent study revealed that MCP SO_1056 of S. oneidensis binds chromate. Here, we show that this MCP also detects an additional attractant (L-malate) and two repellents (nickel and cobalt). The experiments were performed in vivo by the agarose-in-plug technique after overproducing MCP SO_1056 and in vitro, when possible, by submitting the purified ligand-binding domain (LBD) of SO_1056 to a thermal shift assay (TSA) coupled to isothermal titration calorimetry (ITC). ITC assays revealed a K D of 3.4 lM for L-malate and of 47.7 lM for nickel. We conclude that MCP SO_1056 binds attractants and repellents of unrelated composition. The LBD of SO_1056 belongs to the double Cache_1 family and is highly homologous to PctA, a chemoreceptor from Pseudomonas aeruginosa that detects several amino acids. Therefore, LBDs of the same family can bind diverse compounds, confirming that experimental approaches are required to define accurate LBD-binding molecules or signals.

International audience

This review was conducted by the ad hoc subgroup from the working expert group on the risks related to Hyalomma ticks at the French Agency for Food, Environmental and Occupational Health & Safety (ANSES) commissioned by the French authorities.; International audience; At a time of major global, societal, and environmental changes, the shifting distribution of pathogen vectors represents a real danger in certain regions of the world as generating opportunities for emergency. For example, the recent arrival of the Hyalomma marginatum ticks in southern France and the concurrent appearance of cases of Crimean–Congo hemorrhagic fever (CCHF)—a disease vectored by this tick species—in neighboring Spain raises many concerns about the associated risks for the European continent. This context has created an urgent need for effective methods for control, surveillance, and risk assessment for ticks and tick-borne diseases with a particular concern regarding Hyalomma sp. Here, we then review the current body of knowledge on different methods of tick control—including chemical, biological, genetical, immunological, and ecological methods—and the latest developments in the field, with a focus on those that have been tested against ticks from the genus Hyalomma. In the absence of a fully and unique efficient approach, we demonstrated that integrated pest management combining several approaches adapted to the local context and species is currently the best strategy for tick control together with a rational use of acaricide. Continued efforts are needed to develop and implement new and innovative methods of tick control.

Conference of 13th Conference of the International Building Performance Simulation Association, BS 2013 ; Conference Date: 26 August 2013 Through 28 August 2013; Conference Code:100481; International audience; In many countries, ambitious strategies and policies have been deployed to reduce building energy consumption. The method usually advised by standards is the building energy simulation with a large choice of software as TrnSys or EnergyPlus. These dynamic simulation tools are widely used and their results are reliable. However, their major drawback is their lack of flexibility and their complexity with respect to the source code. Moreover, these tools feature exhaustive descriptions of buildings' thermal behaviour, which can be time- consuming when such a degree of accuracy is not required. In this context, we chose to introduce our in-house model. Thus, we give in this article a brief description of this model. Then, we present a comparison and a validation of this model with the numerical software EnergyPlus 011 both small and high insulation monozone buildings. Moreover, we propose to study the effect of merging walls 011 the accuracy and the computation time.

Ce travail aborde le potentiel des travaux concernant l’antifragilite (Taleb, 2012 ; 2013) pour notamment completer le concept de resilience a l’echelle individuelle et organisationnelle. Nous proposons une distinction entre le fragile, le resilient et l’antifragile. Ces capacites se distinguent par la nature des decisions prise en contexte de crise, et la finalite de ces decisions sur l’etat psychologique et professionnel des individus : l’antifragile se renforce par le chaos. Sont ensuite discutees les conditions individuelles et organisationnelles de l’emergence de ces capacites. Nous considerons finalement l’antifragilite aux niveaux organisationnels, des equipes et individuel. Nous introduisons la notion de sentiment d’antifragilite, et posons l’hypothese qu’elle contribue a l’antifragilite entendue comme capacite. Le travail abouti sur la proposition d’un programme de recherche qui aborde le positionnement de ce concept (i.e. les niveaux de son analyse), l’exploration et enfin les outils de mesure a developper.

Island territories’ energy planning is a complex and essential task. In this thesis, the solar energy systems integration into the Corsican electrical grid is built through a multicriteria selection of photovoltaic projects and studies of the solar resource estimation, its variability/prediction and the territorial dispersion of production units.Corsica Island benefits from dynamic energy policies and considerable solar potential that increased the island attractiveness for photovoltaic industrials. Numerous PV plant projects were consequently proposed to local policy maker. The limit of renewable energy source installations connected to a regional-scale electrical grid reduces the number of projects that are likely to be carried out. The multicriteria outranking model ELECTRE IS was implemented to aid the selection of the most restrictive subset of relevant projects, through collaboration between the University of Corsica, the French National Scientific Research Centre and the Haute-Corse departmental Agriculture Chamber. The 16 proposed projects were submitted to 3 preselection constraints, and then evaluated through 8 criteria sweeping away point of views linked to energy, geo-economics, environment, visual impact and land-use conflicts. Criteria parameters, such as relative weights as well as discrimination and veto thresholds are grasped in the selection. The robust result is the recommendation of 4 projects composing the outranking graphs kernels. Among the criteria, the net production appeared delicate to assess. An upstream contribution has been brought through cartography of potential solar over Corsica. It has been generated by the desegregation of Météo-France SATMOS’ Meteosat-8 images, taking into account the relief effects. Both interests of the process were confirmed : errors of solar radiations estimations decreased by 0.1 % to 0.5 % when spatial resolution of the final map increased from 12 km to 90 m.The spatial distribution of resource variations was an issue enlightened by the multicriteria selection and treated in collaboration with EDF. The fluctuations of radiations measured on 11 sites were characterized by applying a new process of classification. This classification allowed demonstrating that intense variations were less frequent by cumulating radiation of dispersed sites, decreasing from 5.4 % or 15.5 % of time to 0.13 % when the phenomenon is optimized. Finally, the prediction of classes was studied ; showing that neural networks and k-nearest neighbour models have the same performances for horizon fewer than 2 hours. They allowed 66.9 % of good predictions for 1 h horizon and 57.1 % for 2 h horizon. For horizons greater than 2 h, the k-NN model presents best performances (until 61.2 % of good predictions for horizon of 6 h)., La planification énergétique en milieu insulaire est une tâche aussi complexe qu’indispensable. Dans cette thèse, l’intégration raisonnée de systèmes énergétiques solaires dans le réseau électrique Corse est pensée au travers d’une sélection multicritère de projets photovoltaïques et de travaux sur l’estimation de la ressource, la caractérisation et prévision de ses fluctuations et le foisonnement territorial.Le dynamisme des politiques énergétiques et le potentiel solaire exceptionnel avaient rendu la Corse attractive pour les industriels du secteur photovoltaïque, si bien qu’en 2008, de nombreux projets d’installations étaient proposés aux décideurs locaux. Or, la limite de production d’énergie intermittente fatale intégrée au réseau électrique réduit le nombre de projets susceptibles d’être concrétisés. Afin d’aider à sélectionner le sous-ensemble le plus restreint de projets pertinents par poste de raccordement, nous avons appliqué le modèle multicritère de surclassement ELECTRE IS ; via une collaboration entre l’Université de Corse, le CNRS et la Chambre Départementale d’Agriculture de Haute-Corse. Les 16 projets candidats furent soumis à 3 contraintes de présélection, puis évalués sur 8 critères balayant les points de vue énergétiques,géo-économiques, écologiques, d’impact visuel et de conflits d’usage des terrains. Les paramètres des critères, tels que leurs poids relatifs ainsi que les seuils de discrimination et de veto ont été appréhendés dans la sélection dont le résultat robuste est la recommandation de 4 projets composant les noyaux des graphes de surclassement.Parmi les critères construits, le productible net est apparu comme délicat à évaluer. Une contribution en amont a été apportée, via une cartographie du potentiel solaire en Corse générée par désagrégation subpixel avec prise en compte des effets du relief d’images Météosat-8 fournies par les services SATMOS de Météo-France. Le double intérêt de la méthode de désagrégation a été confirmé : les erreurs d’estimations du rayonnement solaire diminuent de 0,1 % à 0,5 % alors que la carte finale gagne en résolution spatiale, passant de 12 km à 90 m.Le foisonnement de la ressource est une problématique soulevée par la sélection multicritère opérée en début de thèse et traitée en collaboration avec EDF. Les fluctuations du rayonnement mesuré sur 11 sites ont été caractérisées par l’application d’une nouvelle procédure de classification typologique des variations. Celle-ci a par la suite permis de démontrer le phénomène de foisonnement, les variations les plus intenses étant moins fréquentes, passant de 5,4 % à 15,5 % du temps à 0,13 % par optimisation du phénomène. Enfin la prédictibilité des classes a été étudiée, montrant qu’à un horizon inférieur à 2 heures, les techniques de réseaux de neurones et des k-plus proches voisins permettent 66,9 % de bonnes prédictions à 1 h et 57,1 % à 2 h. Au-delà de 2 h, les k-NN offrent de meilleures performances (jusqu’à 61,2 % de bonnes prédictions à 6 h).

International audience

The Bay of Saint-Cyr (Provence, France, Mediterranean Sea) is the site of two harbours, coastal urban development, trawling, boat anchoring and a sewage outfall. The Posidonia oceanica seagrass distribution was mapped with the help of aerial photographs, side scan sonar and GIS. In addition, the temporal variations of its distribution were studied by aerial photographs and GIS from 1955 to 2000. Finally, coverage and shoot density were measured via scuba-diving. This work reveals (i) the regression of theP. oceanica meadow at sites where harbours have been built, (ii) the occurrence of spaces within the meadow free of live P. oceanica (‘‘intermattes’’), which account for 8% of its surface area, (iii) a deep area where P. oceanica coverage and shoot density are low and (iv) evidence of regression, although modest, of the meadow at its lower limit. Nevertheless, the study site also exhibits an extensive and on the whole relatively healthy meadow whose limits have changed little over time. # 2005 Elsevier B.V. All rights reserved.

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International audience

Dans un contexte marqué par la multiplication, l'intensification des conflits d'usage naissant de l'occupation économique de biens environnementaux et l'objectif de développement durable qui se manifeste notamment dans les plans de développement à l'échelon régional, ce texte aborde la question du développement de l'aquaculture en Corse. Il s'agit plus particulièrement de mettre en relation le cadre de l'action publique et l'initiative privée, tout en tenant compte de la dimension écologique du problème posé, ce qui requiert d'emblée la mise en place d'une réflexion de nature pluridisciplinaire en vue de proposer un système d'aide à la décision pour un acteur public. L'approche développée s'articule autour de la production d'une carte d'aptitude du littoral à l'implantation de nouvelles fermes qui vise à repérer les sites potentiels retenus tant pour leur capacité à favoriser une production de qualité que pour leur faible potentiel polémologène. Incorporant d'emblée les principales dimensions de la problématique soulevée (biologique, juridique, sociale et économique), le texte insiste également sur les enjeux liés au processus d'appropriation d'un outil par les acteurs et la manière dont la règle modèle la coordination entre agents publics et privés qui l'ont implicitement retenu comme référent de la mise en œuvre d'un plan de développement durable de la filière aquacole.

International audience

International audience; Nowadays, the needs for decision making tools useful for people involved in firefighting and/or in landscape management becomes more and more crucial, especially with the dramatic increase of the fire dangerousness and fire severity. These tools have to be accurate enough and faster than real time. Up to now, simulators and other tools are mainly based on empirical or semi-empirical models but the lack of physics in their formulation is a major flaw. The Balbi model is a simplified physical propagation model for surface fires which explicitly depends on the topography, the wind velocity and several fuel characteristics. It is a set of algebraic equations built from usual physical conservation laws (mass, momentum etc.) with some strong assumptions. This work aims at providing a new version of the Balbi model in which the resolution of the rate of spread (ROS) does not need any iterative method any more. This simplification is helpful in implementing the equations set into a fire propagation simulator or a coupled fire-atmosphere simulator. It needs a complete change in the structure of the model and the predicted ROS was tested at the field scale against 179 shrubland fires (burnt in Australia, South Africa, Turkey, Portugal, Spain, New Zealand) and 178 Australian grassland fires with a very good agreement with the observed ROS. Two statistical tools are used to check this agreement (Normalized Mean Square Error, NMSE and Mean Absolute Percentage Error, MAPE) and the Fractional Bias (FB) aims at understanding when the model over-predicts or under-predicts the ROS. The proposed model is accurate and its model parameters are calibrated against a small training dataset which makes it fully predictive whatever the environmental and topographic conditions and the fuel bed characteristics. Its more simple structure allows it to be a good candidate for the heart of a simulation or land management decision making tool.

International audience; Eruptive fires are one category of extreme fire behaviour. They are characterized by a sudden and unpredictable change in the fire behaviour which represents an extreme danger for people involved in firefighting. The major point is about the mechanism that turns a usual fire behaviour into an eruptive fire behaviour. Among the different explanations found in the literature, the pioneering interpretation consisting in a feedback effect caused by the convective flow induced by the fire under wind and/or slope conditions, has never been disproved with an example of fire accident. The main goal of this work lies in proposing a physical modelling of this fire induced wind. This modelling attempt is derived from the brand-new version of the Balbi model, which is a simplified physical model for surface fires at the field scale that explicitly depends on the triangle of fire (fuel bed, wind and slope). This work is a first step to the modelling of fire eruption. The model tries to represent accurately the acceleration of the fire rate of spread propagating on different sloped terrain under no-wind or weak wind conditions. It is tested against three sets of experiments carried out at the laboratory scale without external wind and against a high intensity experimental fire spreading on a steep sloped terrain and conducted under weak wind conditions in the north-western of Corsica. Some statistical tools are used to compare predicted and observed rate of spread (NMSE, Normalized Mean Square Error and MAPE, Mean Absolute Percentage Error) and to understand the model’s under-predictions or over-predictions trends (FB, Fractional Bias).

International audience; Using the fully physical model FireStar3D, a numerical simulation of an eruptive fire was carried out for a grassland on a slopping terrain (30° inclination) and a 10 m-open wind speed of 2 m/s. To reproduce the behaviour of a quasi-infinite fire front, periodic conditions were considered in the fireline direction. The simulation highlights the role played by the additional wind induced by the fire (that reaches about 5.8 m/s at 10 m above ground) and its feedback action on fire behaviour. This interaction results in the transition of the fire behaviour from a plume-dominated fire to a wind-dominated fire, and this goes along with a substantial increase of the rate of spread (from 0.454 m/s to 0.714 m/s) and of the fireline heat release rate (from 4.8 MW/m to 14 MW/m). The fire regime was characterized by Byram’s convection number, based on the effective crosswind speed, that drops from 46.8 to about 3.8 once fire-induced wind takes effect on fire behaviour.

Background: In 2021-2022, influenza A viruses dominated in Europe. The I-MOVE primary care network conducted a multicentre test-negative study to measure influenza vaccine effectiveness (VE). Methods: Primary care practitioners collected information on patients presenting with acute respiratory infection. Cases were influenza A(H3N2) or A(H1N1)pdm09 RT-PCR positive, and controls were influenza virus negative. We calculated VE using logistic regression, adjusting for study site, age, sex, onset date, and presence of chronic conditions. Results: Between week 40 2021 and week 20 2022, we included over 11 000 patients of whom 253 and 1595 were positive for influenza A(H1N1)pdm09 and A(H3N2), respectively. Overall VE against influenza A(H1N1)pdm09 was 75% (95% CI: 43-89) and 81% (95% CI: 45-93) among those aged 15-64 years. Overall VE against influenza A(H3N2) was 29% (95% CI: 12-42) and 25% (95% CI: -41 to 61), 33% (95% CI: 14-49), and 26% (95% CI: -22 to 55) among those aged 0-14, 15-64, and over 65 years, respectively. The A(H3N2) VE among the influenza vaccination target group was 20% (95% CI: -6 to 39). All 53 sequenced A(H1N1)pdm09 viruses belonged to clade 6B.1A.5a.1. Among 410 sequenced influenza A(H3N2) viruses, all but eight belonged to clade 3C.2a1b.2a.2. Discussion: Despite antigenic mismatch between vaccine and circulating strains for influenza A(H3N2) and A(H1N1)pdm09, 2021-2022 VE estimates against circulating influenza A(H1N1)pdm09 were the highest within the I-MOVE network since the 2009 influenza pandemic. VE against A(H3N2) was lower than A(H1N1)pdm09, but at least one in five individuals vaccinated against influenza were protected against presentation to primary care with laboratory-confirmed influenza. This project has received funding from the European Centre for Disease Prevention and Control with in the framework contract ECDC/2018/029. Sí

International audience

Dimensioning a fuelbreak remains always a challenging problem. For a long time, this problem was tackled using an empirical approach from the experience of operational users such as the fire fighters and the foresters. During the last decades, new approaches coming from fire safety engineering have completed the set of tools adapted to study this problem. These tools are all based on physical considerations, more or- less sophisticated. The simplest ones, consist in assimilating the flame as a radiant panel, calculating the distribution of radiant heat flux as a function of the distance separating the flame to a potential target and defining at what distance this heat flux reached a critical threshold level susceptible to produce damages on this target (pain for people or ignition for materials). The most complex ones, consist in solving the conservation equations (mass, momentum, energy ...) governing the behaviour of complex coupled problem formed by the vegetation, the flame front and the surrounding atmosphere. This new generation of engineering tool, based on CFD approach allows to directly predict the behaviour of a fire front propagating toward a fuelbreak, in order to evaluate its efficiency as a function of the amount of surface fuel (grass, shrubs) removed to reduce locally the fuel load and therefore the intensity of an incoming fire. These two approaches are fully complementary, only the first one has the potentiality to be spread operationally on the field, whereas the second one can contribute to improve the first one and to study with more detail some very sensitive situations such as those encountered in the wildland urban interface (WUI). The main part of this study concerns numerical simulations of the propagation of a fire front through a homogeneous vegetation layer (a grassland) in the vicinity of a fuelbreak represented by a band more or less wide inside which all the fuel was removed. The simulations were performed using a fully physical wildfire model (FIRESTAR3D), three variable parameters were considered in this study: the 1m open wind speed (U1 ranged between 3 and 10 m/s), the fuel height (HFuel ranged between 0.25 and 1m) and the fuelbreak width (LFB). With these conditions, the simulations covered a large range of values of the Byram’s convective number NC (0.3 < NC < 60) in order to explore wind as well driven fires (NC < 2) and plume dominated fires (NC > 10). The 72 simulations carried out in this study have been classified in three categories: 1/ Propagation (if the fire has crossed the fuelbreak with a propagation after); 2/ Overshooting or Marginal (if the fire has crossed the fuelbreak without a propagation after); 3/ No-propagation (if the fuelbreak has stopped the fire). The main objective of this study was to determine the optimal fuelbreak width LFBx separating between the Propagation and the No-propagation regimes, in order to generalize the conclusion, the results have been presented in dimensionless form (similitude theory) in representing as an example the ratio LFBx/HFuel versus the Byram’s convective number NC.

International audience; The bulk density as definition represents the ratio between the packing ratio and the density of the vegetation. Therefore, it is directly related to the fuel load, the height and to the porosity of the vegetation. In fact, the bulk density plays an important role in fire propagation and behavior. Due to its dependence on the fuel porosity, the bulk density influences heat transfers inside the fuel bed, so, it can affect directly the rate of spread. Or, the bulk density influences also the fire intensity and flame characteristics (residence time, height and depth) due to its dependence of the fuel load and fuel bed height. However, despite the important influence of the bulk density on fire propagation, the literature does not clarify its impact on fire behavior, different points of view can be exanimated. So, the aim of this study is to investigate the role played by the bulk density upon both propagation parameters and heat transfer of a surface fire through a homogeneous vegetation layer. Investigations were conducted numerically using “FireStar2Dâ€, a complete physical model based on multiphase formulation. Also, experimentally, tests were constructed at the university of Corsica at laboratory scale under no wind and no slope condition. In order to study the elementary effect of the bulk density on fire behavior, three different cases were evaluated: (a) variable fuel load with a constant bulk density, (b) variable fuel load and variable bulk density, (c) variable bulk density with a constant fuel load. Case (a) was only studied numerically, the obtained results are in agreement with the literature: the rate of spread increases with the fuel load until a specific value where the ROS becomes independent of it. Case (b) was evaluated numerically and experimentally using a fix fuel bed height. The numerical and the experimental results showed that the ROS is barely affected by both fuel load and bulk density. Finally, the results of the last case, with a constant fuel load, showed numerically the same tendency proposed by Rothermel: the rate of spread reaches a maximum value at an optimal packing ratio that depends of the surface-volume ratio of the vegetation. Or, experimentally the ROS decreases with the increase of the bulk density. Different variables such as the optical thickness, the fire intensity, the residence time, the radiation and convection heat fluxes have been analyzed.

International audience; Field-scale experiments have been conducted on steep sloped terrains in Speluncatu and Letia, north-western and southern regions of Corsica. This work lies within the GOLIAT project framework and it was provided by the Fire and Rescue Service of North Corsica and the Corsican DFCI (Défense de la Forêt Contre l’Incendie) Group. This work reported high intensity fires propagating through shrub vegetation areas (Genista Salzmannii) lying between 60 cm and 85 cm. These sites were selected because of the density of the vegetation, the high slope angle values with a wind direction aligned with the main slope, which can generate a fire close to wildfire behaviour. A detailed experimental protocol is used in order to determine the propagation conditions and the fire behaviour using UAV cameras and heat flux gauges. In order to investigate the different phenomena encountered in these types of fires, numerical simulations were conducted using a complete physical fire model, based on multiphase formulation, namely FireStar2D. Numerical predictions were used to examine the fire front dynamics related to the fire’s rate of spread and fireline intensity. Despite the unfavourable wind and humidity conditions, experimental results analysis showed that the fireline intensity was higher than 7 MW/m, which means that these fires fall into the category of the very high fire severity. Numerical results predicting the fire’s rate of spread, fireline intensity and fire impact were in good agreement with the experimental data.