719 research outputs found
L'intégration du principe de continuité écologique dans les schémas de cohérence territoriale (SCOT) Analyse de 21 expériences de SCOT
Cette étude s'inscrit dans le cadre des travaux du Comité opérationnel Trame verte et bleue mis en place pour réfléchir aux modalités de mise en place d'une Trame verte et bleue en France, mesure inscrite dans le projet de loi Grenelle 2. à travers un recueil d'expériences de vingt et un schémas de cohérence territoriale (SCOT), l'étude analyse les différentes méthodes d'identification des trames vertes et bleues, les modalités d'intégration de cet outil d'aménagement dans les projets de territoire et les démarches participatives mises en place pour faire adhérer les différents acteurs socio-économiques au projet. L'étude est ponctuée de recommandations pour intégrer la Trame verte et bleue dans un SCOT dans le respect des orientations nationales. / This study is part of the work for the operational committee (COMOP) in charge of formulating the rules and recommendations for implementation of the French ecological network created by the "Grenelle II" law. Based on 21 local development plans (SCOT), the study analyses the different methods used to position local ecological networks, how this planning tool is used in the local development plans and how participative approaches have been developed to ensure that local stakeholders support the project. The study has produced recommendations on how to integrate an ecological network in a SCOT in compliance with national guidelines
Mapping natural habitats using remote sensing and Sparse partial least square discriminant analysis
This work presents a novel approach for mapping the spatial distribution of natural habitats in the "Foothills of Larzac" Natura 2000 listed site located in a French Mediterranean Biogeographical Region. Sparse Partial Least Square Discriminant Analysis was used to analyze two RapidEye datasets (June 2009 and July 2010) with the purpose of choosing the most informative spectral, textural and thematic variables that allow discriminating the classes of habitats. The Sparse Partial Least Square Discriminant Analysis selected relevant and stable variables for the discrimination of habitat classes that could be linked to ecological or biophysical characteristics. It also gave insight into the similarities and the differences between habitats classes with comparable physiognomic characteristics. The highest user accuracy was obtained for dry improved grasslands (u=91.97%) followed by riparian ash woods (u= 88.38%). These results are very encouraging given that these two classes were identified in Annex 1 of the EC Habitats Directive as of community interest. Due to limited data input requirements and to its computational efficiency, the approach developed in this paper is a good alternative to other types of variable selection approaches in a supervised classification framework and can be easily transferred to other Natura 2000 sites
An automatized frequency analysis for vine plot detection and delineation in remote sensing
La mise à disposition d'un outil automatique pour la détection et la caractérisation des parcelles de vigne est un besoin trÚs important d'un point de vue gestion. Un procédé automatique récursif basé sur l'analyse fréquentielle (utilisation de la Transformée de Fourier et des filtres de Gabor) a été développé pour y répondre. Il permet la détermination des contours de parcelle et une estimation précise de leur inter-rang et de leur orientation. Dans l'optique d'une application à grande échelle, les tests et la validation ont été menés à partir de données standard de télédétection à trÚs haute résolution.. Environ 89% des parcelles sont détectées qui correspondent à plus de 84 % de la surface viticole, et 64% d'entre elles avec des contours corrects. L'orientation des rangs et la largeur d'inter-rang sont obtenus avec une précision de 1 degré et 3,3 cm respectivement. / The availability of an automatic tool for vine plot detection, delineation, and characterization would be very useful for management purposes. An automatic and recursive process using frequency analysis (with Fourier transform and Gabor filters) has been developed to meet this need. This results in the determination of vine plot boundary and accurate estimation of interrow width and row orientation. To foster large-scale applications, tests and validation have been carried out on standard very high spatial resolution remotely sensed data. About 89% of vine plots are detected corresponding to more than 84% of vineyard area, and 64% of them have correct boundaries. Compared with precise on-screen measurements, vine row orientation and interrow width are estimated with an accuracy of 1°and 3.3 cm, respectively
"Bacchus" Methodological approach for vineyard inventory and management. Chap.4: Textural and structural analysis
Ce chapitre présente les méthodes qui ont été développées dans le projet Bacchus pour la détection et la caractérisation des parcelles de vigne en imagerie aérienne en se basant sur leur structure. Une analyse texturale est d'abord mise en oeuvre, et complétée par l'introduction de contraintes de régularité des contours pour améliorer la segmentation. Finalement, les parcelles issues de ces premiÚres étapes sont vérifiées et caractérisées au moyen d'une analyse de leur spectre de Fourier. Les résultats obtenus sur diverses zones d'étude du projet Bacchus sont présentés et discutés. / This chapter presents the methodologies that have been developed during the Bacchus project concerning the automatic detection and characterisation of vineyard plots in satellite and aerial images, based on their structural properties. First, a textural analysis has been used. Then shape regularity constraints have been introduced to improve the image segmentation. Finally, the vineyard plots issued from these previous steps are checked and characterised using a Fourier spectrum analysis. Results on various study areas of the Bacchus project are presented and discussed
Ăvreux, Guichainville, Le Vieil-Ăvreux â Zac du Long Buisson
La prescription de diagnostic a portĂ© sur une surface de 90 700 m2 au sud-est de lâagglomĂ©ration actuelle dâĂvreux, en vue de lâamĂ©nagement de la Zac « Le Long Buisson ». La principale intervention dans ce secteur rĂ©alisĂ©e en 2006 au sud et Ă lâest de la parcelle prescrite a donnĂ© lieu Ă des dĂ©couvertes de vestiges datĂ©s du PalĂ©olithique au viie s. (Marcigny et al. 2006). LâopĂ©ration de janvier 2016 a livrĂ© des artefacts lithiques du NĂ©olithique dont un fragment dâanneau plat Ă couronne large..
Saint-SĂ©bastien-de-Morsent â La Fosse aux Buis
Le diagnostic a livrĂ© les vestiges maçonnĂ©s et fossoyĂ©s de plusieurs ateliers de briquetiers et tuiliers, le tracĂ© et les fossĂ©s bordiers de lâancien Chemin de Conches Ă Ăvreux (figurĂ© sur le plan cadastral de 1841), ainsi quâune grande fosse charbonneuse peut-ĂȘtre liĂ©e Ă une activitĂ© mĂ©tallurgique. La plus remarquable dĂ©couverte est celle dâun four de briquetier et de deux fours de tuiliers. Ils sont accompagnĂ©s dâau moins cinq probables fosses de marchage, dâau minimum deux grandes fosses d..
Cell surface properties of two differently virulent strains of Acinetobacter baumannii isolated from a patient
The aim of this study was to unravel, by focusing on cell surface properties, the underlying virulence factors contributing to the difference in the pathogenicity observed in two Acinetobacter baumannii strains isolated from the same patient. The two strains were phenotypically different: (i) a mucoid strain (AB-M), highly virulent in a mouse model of pneumonia, and (ii) a nonmucoid strain (AB-NM), moderately virulent in the same model. The study of the cell surface properties included the microbial adhesion to solvents method, the measurement of the electrophoretic mobility of bacteria, the analysis of biofilm formation by calcofluor white staining, the adherence to silicone catheters, and scanning electron microscopy. The AB-NM strain was more hydrophobic, more adherent to silicone catheters, and produced more biofilm than the AB-M strain. Scanning electron microscopy showed bacterial cells with a rough surface and the formation of large cell clusters for AB-NM whereas the AB-M strain had a smooth surfa..., Le but de cette etude Ă©tait dâĂ©tudier, en se focalisant sur les propriĂ©tĂ©s de surface des bactĂ©ries, des caractĂšres potentiellement impliquĂ©s dans la diffĂ©rence de pouvoir pathogĂšne de deux souches dâAcinetobacter baumannii isolĂ©es chez un mĂȘme patient. Ces souches Ă©taient phĂ©notypiquement diffĂ©rentes : une souche mucoĂŻde (AB-M) caractĂ©risĂ©e par un pouvoir pathogĂšne Ă©levĂ© dans un modĂšle expĂ©rimental murin de pneumopathie, et une souche non mucoĂŻde (AB-NM), plus faiblement pathogĂšne dans le mĂȘme modĂšle. LâĂ©tude des propriĂ©tĂ©s de surface a utilisĂ© la mĂ©thode dâadhĂ©sion des bactĂ©ries aux solvants, la mesure de la mobilitĂ© Ă©lectrophorĂ©tique des bactĂ©ries, lâanalyse de la formation de biofilm par marquage au calcofluor, lâadhĂ©sion Ă des cathĂ©ters en silicone, et la microscopie Ă©lectronique Ă balayage. La souche AB-NM est apparue plus hydrophobe, plus adhĂ©rente aux cathĂ©ters, et plus productrice de biofilm que la souche AB-M. Lâobservation en microscopie Ă©lectronique Ă balayage a montrĂ© des bactĂ©ries Ă surface ..
Imaging angiogenesis in atherosclerosis in large arteries with 68Ga-NODAGA-RGD PET/CT: relationship with clinical atherosclerotic cardiovascular disease.
Integrin alpha-V-beta-3 (αvÎČ3) pathway is involved in intraplaque angiogenesis and inflammation and represents a promising target for molecular imaging in cardiovascular diseases such as atherosclerosis. The aim of this study was to assess the clinical correlates of arterial wall accumulation of <sup>68</sup> Ga-NODAGA-RGD, a specific α <sub>v</sub> ÎČ <sub>3</sub> integrin ligand for PET.
The data of 44 patients who underwent <sup>68</sup> Ga-NODAGA-RGD PET/CT scans were retrospectively analyzed. Tracer accumulation in the vessel wall of major arteries was analyzed semi-quantitatively by blood-pool-corrected target-to-background ratios. Tracer uptake was compared with clinically documented atherosclerotic cardiovascular disease, cardiovascular risk factors and calcified plaque burden. Data were compared using the Mann-Whitney U test, Pearson correlation and Spearman correlation.
<sup>68</sup> Ga-NODAGA-RGD arterial uptake was significantly higher in patients with previous clinically documented atherosclerotic cardiovascular disease (mean TBR 2.44 [2.03-2.55] vs. 1.81 [1.56-1.96], p = 0.001) and showed a significant correlation with prior cardiovascular or cerebrovascular event (r = 0.33, p = 0.027), BMI (Ï = 0.38, p = 0.01), plaque burden (Ï = 0.31, p = 0.04) and hypercholesterolemia (r = 0.31, p = 0.04).
<sup>68</sup> Ga-NODAGA-RGD holds promise as a non-invasive marker of disease activity in atherosclerosis, providing information about intraplaque angiogenesis
Gap, a mycobacterial specific integral membrane protein, is required for glycolipid transport to the cell surface
The cell envelope of mycobacteria is a complex multilaminar structure that protects the cell from stresses encountered in the environment, and plays an important role against the bactericidal activity of immune system cells. The outermost layer of the mycobacterial envelope typically contains species-specific glycolipids. Depending on the mycobacterial species, the major glycolipid localized at the surface can be either a phenolglycolipid or a peptidoglycolipid (GPL). Currently, the mechanism of how these glycolipids are addressed to the cell surface is not understood. In this study, by using a transposon library of Mycobacterium smegmatis and a simple dye assay, six genes involved in GPLs synthesis have been characterized. All of these genes are clustered in a single genomic region of approximately 60 kb. We show by biochemical analyses that two non-ribosomal peptide synthetases, a polyketide synthase, a methyltransferase and a member of the MmpL family are required for the biosynthesis of the GPLs backbone. Furthermore, we demonstrate that a small integral membrane protein of 272 amino acids named Gap (gap: GPL addressing protein) is specifically required for the transport of the GPLs to the cell surface. This protein is predicted to contain six transmembrane segments and possesses homologues across the mycobacterial genus, thus delineating a new protein family. This Gap family represents a new paradigm for the transport of small molecules across the mycobacterial envelope, a critical determinant of mycobacterial virulence
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