Éditeur(s) : A. Challamel A. Challamel ( Paris )
France

000586576
ADB5259
f 01002220

Éditeur(s) : HAL CCSD BioMed Central
Résumé : International audience
BACKGROUND: Sampling design is a key issue when establishing species inventories and characterizing habitats within highly heterogeneous landscapes. Sampling efforts in such environments may be constrained and many field studies only rely on subjective and/or qualitative approaches to design collection strategy. The region of Cacao, in French Guiana, provides an excellent study site to understand the presence and abundance of Anopheles mosquitoes, their species dynamics and the transmission risk of malaria across various environments. We propose an objective methodology to define a stratified sampling design. Following thorough environmental characterization, a factorial analysis of mixed groups allows the data to be reduced and non-collinear principal components to be identified while balancing the influences of the different environmental factors. Such components defined new variables which could then be used in a robust k-means clustering procedure. Then, we identified five clusters that corresponded to our sampling strata and selected sampling sites in each stratum. RESULTS: We validated our method by comparing the species overlap of entomological collections from selected sites and the environmental similarities of the same sites. The Morisita index was significantly correlated (Pearson linear correlation) with environmental similarity based on i) the balanced environmental variable groups considered jointly (p = 0.001) and ii) land cover/use (p-value<0.001). The Jaccard index was significantly correlated with land cover/use-based environmental similarity (p-value = 0.001). CONCLUSIONS: The results validate our sampling approach. Land cover/use maps (based on high spatial resolution satellite images) were shown to be particularly useful when studying the presence, density and diversity of Anopheles mosquitoes at local scales and in very heterogeneous landscapes.
BMC Ecology

pasteur-00914104
https://hal-riip.archives-ouvertes.fr/pasteur-00914104
https://hal-riip.archives-ouvertes.fr/pasteur-00914104/document
DOI : 10.1186/1472-6785-13-45
PUBMED : 24289184

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Purpose: Active surveillance is a treatment option for favorable risk prostate cancer. However, data are missing on populations of African descent. We evaluated the safety and benefit of active surveillance in an African Caribbean cohort with favorable risk prostate cancer. Materials and Methods: Between 2005 and 2016, a single center, prospective cohort study was performed in Guadeloupe, French West Indies, including patients on active surveillance who had low risk prostate cancer (prostate specific antigen 10 ng/ml or less and Gleason score 6 or less) or favorable intermediate risk prostate cancer (prostate specific antigen 10 to 20 ng/ml, Gleason score 3 + 4 or less and life expectancy less than 10 years). Treatment was recommended in case of grade progression, increased tumor volume, prostate cancer doubling time less than 36 months or patient wish. Overall survival, disease specific survival and duration of active surveillance were calculated with the KaplanMeier method. Multivariate analysis was performed using the Cox proportional hazards model to identify predictors of active surveillance termination. Results: A total of 234 patients with a median age of 64 years were enrolled in study. Median followup was 4 years (IQR 2.3-5.5). Overall survival at 30 months, 5 years and 10 years was 99.5%, 98.5% and 90.7%, respectively. Disease specific survival at 30 months, and 5 and 10 years was 100%. At 30 months, 5 years and 10 years 72.7%, 52.6% and 40.4% of patients, respectively, remained untreated and on active surveillance. Age (HR 0.96 per additional year, 95% CI 0.93-0.99) and prostate specific antigen density (HR 1.52 per additional 0.1 ng/ml, 95% CI 1.20-1.89) were found to be independent predictors of active surveillance termination. Conclusions: Active surveillance is safe and beneficial for highly selected African Caribbean patients. It seems to be feasible for patients at low risk and intermediate favorable risk. Prostate specific antigen density could help better select these patients.
ISSN: 0022-5347

hal-01519251
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01519251
DOI : 10.1016/j.juro.2016.12.047
PUBMED : 27993665

Éditeur(s) : HAL CCSD BioMed Central
Résumé : International audience
The nine countries sharing the Amazon forest accounted for 89% of all malaria cases reported in the Americas in 2008. Remote sensing can help identify the environmental determinants of malaria transmission and their temporo-spatial evolution. Seventeen studies characterizing land cover or land use features, and relating them to malaria in the Amazon subregion, were identified. These were reviewed in order to improve the understanding of the land cover/use class roles in malaria transmission. The indicators affecting the transmission risk were summarized in terms of temporal components, landscape fragmentation and anthropic pressure. This review helps to define a framework for future studies aiming to characterize and monitor malaria.
ISSN: 1475-2875

inserm-00834790
http://www.hal.inserm.fr/inserm-00834790
http://www.hal.inserm.fr/inserm-00834790/document
http://www.hal.inserm.fr/inserm-00834790/file/1475-2875-12-192.pdf
DOI : 10.1186/1475-2875-12-192

Éditeur(s) : HAL CCSD Elsevier
Résumé : Differentiation of the Earth's mantle and formation of continental and oceanic crust occur principally through partial melting and extraction of basaltic melt. Among the mantle rocks occurring at the Earth's surface, as tectonically-emplaced massifs, abyssal peridotites or xenoliths, the harzburgites (< 5% clinopyroxene) are widely considered as refractory mantle residues left after extraction of a basaltic component. In contrast, the most fertile lherzolites (15% clinopyroxene) are generally regarded as pristine mantle, only weakly affected by partial melting. In this paper we present new convergent structural and geochemical data from the Lherz massif, the type-locality of lherzolite, indicating that the lherzolites from Lherz do not represent pristine mantle. Detailed structural mapping clearly shows that the lherzolites are secondary rocks formed at the expense of the harzburgites. Variations of major, minor and trace elements through the harzburgite–lherzolite contacts indicate that the lherzolites were formed through a refertilization process involving interaction of refractory, lithospheric mantle with upwelling asthenospheric partial melts. Combined with previously published indications of refertilization in orogenic peridotites, our new observations in Lherz suggest that most lherzolite massifs represent secondary (refertilized) rather than pristine mantle. Together with geochemical data on mantle xenoliths, this indicates that melt transport and melt-rock reaction play a key role on the rejuvenation and erosion of the lithospheric mantle.
ISSN: 0012-821X

hal-00406433
https://hal.archives-ouvertes.fr/hal-00406433
DOI : 10.1016/j.epsl.2007.05.026

Éditeur(s) : HAL CCSD MDPI
Résumé : International audience
Malaria remains one of the most common vector-borne diseases in the world and the definition of novel control strategies can benefit from the modeling of transmission processes. However, data-driven models are often difficult to build, as data are very often incomplete, heterogeneous in nature and in quality, and/or biased. In this context, a knowledge-based approach is proposed to build a robust and general landscape-based hazard index for malaria transmission that is tailored to the Amazonian region. A partial knowledge-based model of the risk of malaria transmission in the Amazonian region, based on landscape features and extracted from a systematic literature review, was used. Spatialization of the model was obtained by generating land use and land cover maps of the cross-border area between French Guiana and Brazil, followed by computing and combining landscape metrics to build a set of normalized landscape-based hazard indices. An empirical selection of the best index was performed by comparing the indices in terms of adequacy with the knowledge-based model, intelligibility and correlation with P. falciparum incidence rates. The selected index is easy to interpret and successfully represents the current knowledge about the role played by landscape patterns in malaria transmission within the study area. It was significantly associated with P. falciparum incidence rates, using the Pearson and Spearman correlation coefficients (up to 0.79 and 0.75, respectively; p-value < 0.001), and the linear regression coefficient of determination (reaching 0.63; p-values < 0.001). This study establishes a spatial knowledge-driven, landscape-based hazard malaria index using remote sensing that can be easily produced on a regular basis and might be useful for malaria prediction, surveillance, and control. Keywords: remote sensing; land use and land cover; landscape metric; knowledge-based hazard modeling; malaria; cross-border area between French Guiana and Brazil
ISSN: 2072-4292

hal-01355255
https://hal.archives-ouvertes.fr/hal-01355255
https://hal.archives-ouvertes.fr/hal-01355255/document
https://hal.archives-ouvertes.fr/hal-01355255/file/010066865.pdf
IRD : fdi:010066865

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
The number of satellites and sensors devoted to Earth observation has become increasingly elevated, delivering extensive data, especially images. At the same time, the access to such data and the tools needed to process them has considerably improved. In the presence of such data flow, we need automatic image interpretation methods, especially when it comes to the monitoring and prediction of environmental and societal changes in highly dynamic socio-environmental contexts. This could be accomplished via artificial intelligence. The concept described here relies on the induction of classification rules that explicitly take into account structural knowledge, using Aleph, an Inductive Logic Programming (ILP) system, combined with a multi-class classification procedure. This methodology was used to monitor changes in land cover/use of the French Guiana coastline. One hundred and fifty-eight classification rules were induced from 3 diachronic land cover/use maps including 38 classes. These rules were expressed in first order logic language, which makes them easily understandable by non-experts. A 10-fold cross-validation gave significant average values of 84.62%, 99.57% and 77.22% for classification accuracy, specificity and sensitivity, respectively. Our methodology could be beneficial to automatically classify new objects and to facilitate object-based classification procedures.
ISSN: 0098-3004

hal-01369822
https://hal.archives-ouvertes.fr/hal-01369822
https://hal.archives-ouvertes.fr/hal-01369822/document
https://hal.archives-ouvertes.fr/hal-01369822/file/CAGEO-D-13-00538R1_article.pdf
DOI : 10.1016/j.cageo.2014.08.013

Éditeur(s) : Gauthier-Villars
Résumé : The benthic macroinvertebrate assemblages of the Argentine continental shelf were studied from samples of molluscs, echinoderms and bryozoans collected by the RN Shinkai Maru. Two major faunal groups were distinguished: one inhabiting the warmer inner shelf off Buenos Aires and northern Patagonia, and the other occupying the colder middle and outer shelf off Buenos Aires and most of the Patagonian shelf. These results confirm the traditional biogeographic division of the Argentine continental shelf into two provinces: Argentine and Magellanic. Furthermore, the results suggest the possibility of subdividing the Atlantic sector of the Magellanic province into two districts: Patagonian and Malvinean, under the influence of the Patagonian and the Malvinas current, respectively.
Oceanologica Acta (0399-1784) (Gauthier-Villars), 1992 , Vol. 15 , N. 6 , P. 687-698

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/00101/21234/18851.pdf
http://archimer.ifremer.fr/doc/00101/21234/

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Le groupe de recherche sur les avancées en pneumo-pédiatrie (GRAPP) a élaboré en 2013 des recommandations sur l'utilisation des nouveaux outils diagnostiques dans les infections respiratoires basses de l'enfant de plus de trois mois. Ces recommandations sont présentées ici en un texte court, le texte long est disponible sur le site de la Société française de pédiatrie www.sfpediatrie.com et de la Société pédiatrique de pneumologie et d'allergologie (SP2A) www.sp2a.fr.
ISSN: 0929-693X

hal-00994569
https://hal-univ-rennes1.archives-ouvertes.fr/hal-00994569
DOI : 10.1016/j.arcped.2014.01.004
PUBMED : 24613479