Éditeur(s) : HAL CCSD
Résumé : International audience
Numerous social network mining methods have been proposed until now for addressing social mining tasks and specially searching for communities or frequent social patterns. However, the degree of complementarity of these methods has been very little studied. In this paper, we focus on two knowledge extraction processes in social networks: a link-based clustering that may extract social communities and a recent approach that searches for frequent conceptual link involving both clustering and search for frequent social patterns. We explore how the models extracted by each method may match and which potential useful knowledge they may provide. Our objective is to evaluate the potential relationships between communities and frequent conceptual links. For this purpose, we propose a set of measures for evaluating the degree to which these patterns extracted from the same dataset are matching. Our approach is applied on two datasets and demonstrates the importance of considering simultaneously various kinds of knowledge and their complementarity.
IEEE/ACM International Conference on Advances in Social Networks Analysis and Mining
Niagara falls, Canada

hal-00874351
https://hal.archives-ouvertes.fr/hal-00874351

Éditeur(s) : Springer
Résumé : The great fecundity and very high larval mortality of most marine invertebrates and fish make possible substantial variance in the number of offspring contributed by adults to subsequent generations. The reproductive success of such organisms may thus resemble a sweepstakes lottery, in which a minority of progenitors succeeds in replacing an entire population, while the majority fails to procreate. One specific prediction of this hypothesis, that genetic diversity of newly settled cohorts should be less than that of the adult population, is tested in the present study. Microsatellite DNA markers were examined in naturally spawned juvenile European flat oysters Ostrea edulis (L.), collected over a 12-day period in 1993 from the western Mediterranean Sea, near Sete, France (43 degrees 32'N, 3 degrees 56'E) and grown out for a period of up to 10 months. Variation in these juveniles was compared to that in a pooled sample of adults collected in 1994 from two locations (Thau Lagoon and Port St. Louis) that had statistically homogeneous allelic frequencies. Though nearly twice as large as the pooled adult sample, the juvenile sample had only 60% of the adult allelic diversity. Analyses of linkage disequilibrium and kinship, as well as estimation of the effective number of parents, suggested that 10-20 adults produced this juvenile cohort. This observation supports the hypothesis of sweepstakes reproductive success and suggests that partial inbreeding may occur even in species with large populations and dispersing planktonic larvae.
Marine Biology (0025-3162) (Springer), 2007-03 , Vol. 150 , N. 6 , P. 1173-1182

Droits : 2007 Springer
http://archimer.ifremer.fr/doc/2007/publication-2616.pdf
DOI:10.1007/s00227-006-0441-y
http://archimer.ifremer.fr/doc/00000/2616/

Éditeur(s) : HAL CCSD
Résumé : International audience
The paper proposes a new knowledge discovery method called MAX-FLMin for extracting frequent patterns in social networks. Unlike traditional approaches that mainly focus on the network topological structure, the originality of our solution is its ability to exploit information both on the network structure and the attributes of nodes in order to elicit specific regularities that we call "Frequent Links". This kind of patterns provides relevant knowledge about the groups of nodes most connected within the network. First, we detail the method proposed to extract maximal frequent links from social networks. Second, we show how the extracted patterns are used to generate aggregated networks that represent the initial social network with more semantics. Qualitative and quantitative studies are conducted to evaluate the performances of our algorithm in various configurations.
Database (Weston, Conn.) and Expert Systems Applications
Vienna, Austria

hal-00767052
https://hal.archives-ouvertes.fr/hal-00767052
DOI : 10.1007/978-3-642-32600-4_35

Éditeur(s) : Université des Antilles Études caribéennes
Résumé : L’organisation et la gestion des espaces publics en milieu urbain sont au centre des préoccupations de la puissance publique. Cet intérêt est lié dans les pays en développement aux nombreux dysfonctionnements recensés dans la ville. Ces difficultés sont entretenues par la démographie galopante, l’urbanisation informelle et à l’accroissement des activités industrielles, commerciales entre autres. À Dakar, la question de la mobilité urbaine est exacerbée par les puissants mouvements pendulaires entre la ville centrale et la périphérie amplifiés par les stationnements anarchiques et par l’inorganisation des modes de transports urbains.Le type d’espace public choisi pour cet article est une gare routière située au cœur du Plateau de Dakar : Petersen. Elle apparaît comme l’une des plus importantes gares routières du pays, surtout en matière de fréquentation avec plus de 50 000 personnes par jour. Le mode de gestion appliqué ici est la concession, une convention par laquelle la puissance publique confie la gestion de l’équipement à la SAGES une structure privée prenant en charge les intérêts parfois très contradictoires des différents acteurs.
The organization and management of public spaces in urban areas is a central concern of public authorities. This interest is linked in developing countries with numerous shortcomings identified in the city. These difficulties sustained by massive population growth, urbanization informal, and increased industrial activities, commercial and others. In Dakar, the question of urban mobility is exacerbated by the significant commuting between the city center and the periphery that are amplified by the chaotic parking lots and the disorganization of urban transport modes.The type of public space chosen for this article is a bus station in the heart of the Plateau de Dakar: Petersen. It appears as one of the largest bus stations in the country, especially in terms of attendance with over 50,000 people per day.The management method applied here is the concession, an agreement by which the public entrusts the management of equipment at the SAGES, a private organization that supports some very conflicting interests of different actors.
Sénégal
Dakar

Droits : info:eu-repo/semantics/openAccess
urn:doi:10.4000/etudescaribeennes.7858
http://journals.openedition.org/etudescaribeennes/7858

Éditeur(s) : HAL CCSD Human Kinetics
Résumé : International audience
Purpose: Postexercise alveolar-capillary membrane-diffusing capacity (DLco) often decreases in highly trained endurance athletes and seems linked to their training status. To test the hypothesis that training status influences postexercise DLco, 13 male and 2 female triathletes (20.2 ± 4.4 y old, 175.2 ± 6.7 cm tall; weight in a range of 66.6 ± 7.4 kg to 67.4 ± 7.8 kg during the 1-y study) were randomized into experimental (n = 7) and control (n = 8) groups and performed VO2max cycle tests and simulated cycle-run successions (CR) of 30 min + 20 min after 3 periods in the competitive season. Methods: Both groups were tested before (pre- HTP) and after a 30-wk high-training period (HTP) with high training volume, intensity, and frequency. The experimental group was then also tested after a 6-wk low-training period (LTP) with low training volume, intensity, and frequency, while the control group continued training according to the HTP schedule for these 6 wk. Ventilatory data were collected continuously. DLco testing was performed before and 30, 60, and 120 min after the CR trials. Results: Whatever the period or group, DLco was significantly decreased 30 min after CR, with a significantly greater decrease in the experimental group than the control group in LTP (–15.7% and –9.3% of DLco, respectively). Conclusions: Six weeks of low training volume and intensity were sufficient to reverse the effects of high training volume and intensity on the alveolar-capillary membrane after a CR succession in competitive triathletes.
ISSN: 1555-0265

hal-01163434
https://hal.univ-antilles.fr/hal-01163434

Éditeur(s) : Elsevier Sci Ltd
Résumé : Several marine geophysical data and piston-coring surveys acquired during the last decade allow one to better understand the close dynamic interactions between the sand-rich Orinoco turbidite system and the compressional structures of the Barbados prism. These interactions have been active since Eocene time as illustrated by the study of outcrops onshore Barbados Island. Because of strong morphologic and tectonic control in the east-Caribbean active margin, the present-day Orinoco turbiditic pattern system does not exhibit a classic fan geometry. The sea-floor geometry between the slope of the front of the Barbados prism and the slope of the South-American margin induces the convergence of the turbidite channels toward the abyssal plain, at the front of the accretionary prism. Also, whereas in most passive margins the turbidite systems are organized upstream to downstream as canyon, channel-levee and lobes, here, due to the tectonic control, the sedimentary system is organized upstream to downstream as channel-levee, canyons and channelized lobes. Indeed, at the edge of the Orinoco platform, the system has multiple sources with several distributaries and downstream the channel courses are complex with frequent convergences or divergences that are emphasized by the effects of the undulating seafloor tectonic morphologies associated with active thrust tectonics and mud volcanism. On top of the accretionary prism, turbidite sediments are filling transported piggy-back basins whose timing of sedimentation vs. deformation is complex. While erosion processes are almost absent on the highly subsiding Orinoco platform and in the upper part of the turbidite system, they develop mostly between 2000 and 4000 m of water depth, above the compressional structures of the Barbados prism (canyons up to 3 km wide and 300 m deep). In the abyssal plain, the main turbiditic channel develops toward the east and connects with the Vidal mid-Atlantic channel. The sediments transported in this channel are filling several elongated basins linked with fracture zones (notably the Barracuda Basin), and finally end their course in the Puerto-Rico trench, the deepest morphologic depression of the region. Piston-cores have demonstrated that turbidite sediments above the accretionary prism and in the abyssal plain are mostly coarse sandy deposits covered by recent pelagic planktonic-rich sediments, which corresponds to slower sand deposition during the post-glacial sea level rise. Numerical stratigraphic modelling suggests that during the last glacial event, the main depocentres were located above the tectonic prism and in the abyssal plain, at the front of the prism and that, during the Holocene eustatic rise, a large accommodation space formed on the shelf confining sedimentation mostly on the Orinoco deltaic platform and producing a starvation downstream in the turbidite system.
Marine And Petroleum Geology (0264-8172) (Elsevier Sci Ltd), 2015-06 , Vol. 64 , P. 76-103

Droits : 2015 Elsevier Ltd. All rights reserved.
http://archimer.ifremer.fr/doc/00252/36373/34913.pdf
DOI:10.1016/j.marpetgeo.2014.12.015
http://archimer.ifremer.fr/doc/00252/36373/

Éditeur(s) : Amer Soc Limnology Oceanography
Résumé : A new benthic station equipped with oxygen microelectrodes and environmental sensors was developed by Laboratoire des Sciences du Climat et de L’Environnement (LSCE) and Division Technique of the Institut National des Sciences de L’Univers (DT-INSU) to perform in situ time series monitoring of sediment oxygen demand, linked to the mineralization of organic matter. The time series typically cover periods of 2-3 months, with a base frequency of 1 set of oxygen profiles per day. The profiling head assessed the lateral heterogeneity of the sediment oxygen demand at the beginning of the time series over a 0.8-m long rectangle to discriminate spatial and temporal variability. A continuous recalibration is performed using a moored oxygen optode anchored to the benthic station together with a set of environmental sensors. These sensors (turbidity, temperature, salinity, and oxygen) can trigger a high-frequency profiling mode to investigate the fate of particulate organic matter delivered during floods, resuspension, and deposition events. Deployments of the benthic station were performed in the Rhone River subaqueous delta (Mediterranean Sea). We show that “stable” periods (when neither floods nor storms occur) were characterized by a stable oxygen demand. In the case of resuspension events, an increase of the sediment oxygen demand by a factor of 2-3 with a relaxation time of 1 day was observed, indicating that the new benthic station can adequately capture the impact of resuspension events on the oxygen demand in deltaic sediments.
Limnology And Oceanography-methods (1541-5856) (Amer Soc Limnology Oceanography), 2014-11 , Vol. 12 , P. 729-741

Droits : 2014, by the American Society of Limnology and Oceanography, Inc.
http://archimer.ifremer.fr/doc/00230/34126/32597.pdf
http://archimer.ifremer.fr/doc/00230/34126/36349.pdf
DOI:10.4319/lom.2014.12.729
http://archimer.ifremer.fr/doc/00230/34126/

Éditeur(s) : Université des Antilles Études caribéennes
Résumé : Ce numéro de la Revue Études Caribéennes s’intéresse aux liens qui unissent et opposent l’activité touristique et les ressources naturelles, particulièrement dans les pays du Sud. Dans un contexte de médiatisation accrue des enjeux liés à la biodiversité et aux menaces qui pèsent sur elle, le tourisme – et particulièrement l’écotourisme – est souvent présenté comme un moyen de concilier la conservation et le développement. Les autorités locales, malgré l’existence d’un cadre réglementaire propre à l’environnement, ne disposent souvent pas de moyens suffisants (humains, matériels et financiers) pour gérer la croissance de la fréquentation des aires protégées et ses effets potentiels sur l’environnement naturel et humain. En réponse à cette problématique, les institutions financières internationales et les organismes associés proposent aux pays du Sud de trouver un équilibre entre une fréquentation de masse et une fréquentation de bas volume afin de développer « un tourisme de haute qualité ». Même si cela était possible, quels critères peuvent être utilisés pour « cesser » le développement d’un pôle ou d’une région touristique ? L’évolution géographique « naturelle » du tourisme – c’est-à-dire essentiellement basée sur la mise en tourisme de la nature et sur l’accessibilité de ces ressources – pose déjà des problèmes politiques et économiques importants. Les gouvernements (central, régional ou local) sont difficilement en mesure de réaliser un arbitrage de long terme dans ce contexte qui permettrait l’adéquation entre le développement touristique et la préservation des espaces naturels. La relation entre le tourisme et les ressources naturelles s’articule souvent autour de deux objectifs spécifiques, soient : développer un produit à moindre impact, mais aux dépenses élevées et viser un volume de visiteurs qui contribue aux profits économiques, mais qui amène le moins de dégradation écologique/sociale possible. Cette position résume à elle seule à la fois la complexité et les multiples paradoxes dans lesquels s’insère la mise en tourisme de la nature. Les dynamiques sociales et l’extension de l’appropriation privative des espaces naturels et agricoles posent la problématique des modes de gestion des ressources communes et de leur pérennité, particulièrement dans les pays du Sud. Dans ce contexte, les objectifs, les ressources et les stratégies des principaux acteurs concernés sont difficilement conciliables et le système de relation qu’il induit n’est pas nécessairement en phase avec les finalités poursuivies. This edition of Revue Etudes Caribéennes focuses on the links that unite and oppose tourism and natural resources, specifically in southern countries. In a context of increased media coverage of issues related to biodiversity (including threats to it), tourism – particularly ecotourism – is often presented as a mean to reconcile conservation and development. Local authorities, despite the existence of a specific environmental regulatory framework, often have insufficient resources (human, material, financial) to manage the increase of visits to protected areas, and the potential impact of these visits on natural and human environments. In response to this problem, international financial institutions and associated organizations offer to try to find a balance between mass attendance and low volume attendance in order to develop "high quality tourism" in southern countries. Even if this were possible, what criteria can be used to "stop" the development of a tourist site or region for environmental reasons? The “natural” geographic evolution of tourism – in other words, essentially based on the development of nature tourism and accessibility of these resources – already causes huge political and economic problems. Governments (central, regional or local) are hardly able to arbitrate over the long term in a context that would allow finding a balance between tourism development and preservation of natural areas. The relationship between tourism and natural resources often revolves around two specific objectives: to develop a product with less impact, but at high cost and a target volume of visitors that contributes to economic profits, but that causes the least ecological / social degradation possible. This position epitomizes both the complexity and the many paradoxes of nature tourism development. Social interactions and the expansion of private appropriation of natural and agricultural areas highlight the challenges of managing common resources and their sustainability, especially in the southern countries. In this context, development objectives, natural resources and the strategies of key stakeholders are difficult to reconcile, and the relationship between leading actors do not always correspond with these objectives. Esta edición de “Revue Études Caribéennes” se interesa a los lazos que unen y separan la actividad turística y los recursos naturales, particularmente en los países del sur. En un contexto de mediatización en alza sobre los objetivos ligados a la biodiversidad y a las amenazas que pesan sobre ella, el turismo – y particularmente el ecoturismo – está a menudo presentado como un medio de conciliar la conservación y el desarrollo. Las autoridades locales, pese a la existencia de un cuadro propio de reglamentación al medio ambiente, no disponen habitualmente de suficientes medios (humanos, materiales y financieros) para controlar el aumento de visitas en las áreas protegidas y sus efectos potenciales sobre el ambiente natural y humano. En respuesta a esta problemática, las instituciones financieras internacionales y los organismos asociados proponen a los países del sur encontrar un equilibrio entre la frecuentación de masas y una frecuentación de bajo volumen con el objetivo de desarrollar “un turismo de alta calidad”. Incluso si fuese posible, ¿qué criterios podrían ser utilizados para “cesar” el desarrollo de un centro o una región turística? La evolución geográfica “natural” del turismo – esencialmente basada en el desarrollo del turismo de la naturaleza y el acceso de sus recursos – crean problemas políticos y económicos enormes. Los gobiernos (central, regional o local) tienen dificultades para realizar un arbitraje a largo plazo en este contexto que permitiría la adecuación entre el desarrollo turístico y la preservación de los espacios naturales. La relación entre el turismo y los recursos naturales se articula a menudo alrededor de dos objetivos específicos, sean: desarrollar un producto con mínimo impacto, pero con gastos elevados y aspirar a un volumen de visitantes que contribuya a las ganancias económicas, pero que traiga la menor degradación ecológica/social posible. Esta posición resume la complejidad y las múltiples paradojas en las cuales se encaja la puesta del turismo en la naturaleza. Las dinámicas sociales y la extensión de la apropiación privativa de los espacios naturales y agrícolas plantean una problemática en los modos de gestión de los recursos comunes y de su perennidad, particularmente en los países del sur. En este contexto, los objetivos, los recursos y las estrategias de los principales actores concernidos son difícilmente conciliables y el sistema de relación que induce no es necesariamente en la misma fase con los objetivos perseguidos.

Droits : info:eu-repo/semantics/openAccess
urn:doi:10.4000/etudescaribeennes.7884
http://journals.openedition.org/etudescaribeennes/7884

Éditeur(s) : Université des Antilles Études caribéennes
Résumé : Sur la base d’une modélisation stylisée d’une économie bi-sectorielle fréquentée par les touristes la présentation rappelle que le lien tourisme-pauvreté peut être lu selon une causalité inverse ; de la pauvreté vers le tourisme. Cette lecture « inversée » s’appuie sur deux éléments : le tourisme impose nécessairement un choix aux résidents : quelle est la part du produit local à laisser aux visiteurs ? la richesse donc la pauvreté influe sur la volonté de réception des résidents, quand le flux touristique est contraint.
Based on a stylized model of a two-sector economy frequented by tourists, this paper argues that the tourism-poverty link may be understood in a reverse causality; from poverty to tourism. This "reverse" understanding is based on two elements: Tourism necessarily presents a choice for residents: what part(s) of the local product should tourists be allowed access to? When the flow of tourism is constrained, the willingness of local residents to accommodate tourists is more heavily influenced by quality of life.

Droits : info:eu-repo/semantics/openAccess
urn:doi:10.4000/etudescaribeennes.6477
http://journals.openedition.org/etudescaribeennes/6477

Éditeur(s) : HAL CCSD BioMed Central
Résumé : International audience
BACKGROUND:In French Guiana, a French overseas territory in South America, 6 to 10 thousands undocumented persons work illegally in gold mining sites in the Amazonian forest. Precarious life conditions lead to poor health but few data exist on the health status of illegal gold miners in French Guiana. The objective of this article was to describe the sociodemographic and health status of this vulnerable population.METHOD:A prospective cross-sectional survey was conducted in 2015 on gold mine supply sites at the border between French Guiana and Suriname. Health status was assessed through medical examination, past medical history, haemoglobin concentration, and HIV and malaria testing. A questionnaire was used to collect data about the migration itinerary and life conditions on mining sites.RESULTS:Among the 421 adults included in the study, 93.8% (395/421) were Brazilian, mainly from Maranhão (55.7%, 220/395), the poorest Brazilian state. The sex ratio was 2.4. Overall, 48% of persons never went to school or beyond the primary level. The median time spent in gold mining was quite long (10 years), with a high turn-over. One third of the surveyed population (37.1%, 156/421) had high blood pressure, and only two had a medical follow-up. Most persons had experienced malaria (89.3%, 376/421). They declared frequent arboviroses and digestive disorders. Active leishmaniasis was observed in 8.3% of gold miners. Among women, 28.5% were anemic. Concerning HIV, 36.6% (154/421) of persons, mainly men, never got tested before and 6 were tested positive, which represented an HIV prevalence of 1.43% (95%CI =0.29-2.5).CONCLUSION:These findings support the hypothesis that mining in remote areas is linked to several specific illnesses. Theoretically, gold miners would be presumed to start their economical migration to French Guiana as a healthy group. However, their strenuous working and living conditions there lead to poor health caused by infectious and non infectious diseases. This description of their health status is precious for health policy planners in French Guiana given the importance of controlling communicable disease, and the severity and range of specific illnesses acquired by this neglected population.TRIAL REGISTRATION:Clinical trial registration PRS N° NCT02903706 . Retrospectively registered 09/13/2016.
ISSN: 1471-2458

inserm-01566314
http://www.hal.inserm.fr/inserm-01566314
http://www.hal.inserm.fr/inserm-01566314/document
http://www.hal.inserm.fr/inserm-01566314/file/2017%2C%20Douine%20-%20Illegal%20gold%20miners%20in%20French%20Guiana.pdf
DOI : 10.1016/S0140-6736(10)62169-1

Éditeur(s) : HAL CCSD
Résumé : International audience
Since long years, the archaeologists have analyzed the migrations link to the pre-Columbian settlement of the Antillean archipelago. On an other hand, the researches about the origins of the raw materials have demonstrated the importance of the inter-insular exchanges, exchanges not only of material elements but even of concepts and persons. This is those relations who permitted the development of real Antillean civilizations. Sadly, the off shore canoe, real civilizational tool, and the different aspects link to is utilization have been frequently absent of the discussion or only analyzed from a theoretical point of view by the meaning of modelization tries. The "Ioumoúlicou" project we will present now is an experimental archaeological program dedicated to the study of the pre-Columbian navigation conditions and techniques. Those works realized in a scientifically controlled frame completed by a canoe hydrostatic parameters analysis, gave us the possibility to obtain totally original data. Those data give us an opportunity to refund our vision of the relation of the pre-Columbian peoples with the archipelagic Antillean space.
Depuis plusieurs décennies, les recherches archéologiques ont mis en évidence plusieurs mouvements migratoires à l'origine du peuplement précolombien de l'archipel antillais. D'autre part, les travaux réalisés sur l'origine des matières premières ont permis de souligner l'importance des échanges inter-insulaires, des échanges de biens matériels mais aussi d'idées et de personnes. Ce sont ces relations qui ont permis le développement de véritables civilisations antillaises. Malheureusement, le canot de haute mer, véritable outil civilisationnel, et les différents aspects liés à son utilisation ont trop souvent été les grands absents du débat ou approchés uniquement d'une point de vue théorique au travers de tentatives de modélisation. Le projet "Ioumoúlicou" que nous allons vous présenter ici correspond à un programme d'archéologie expérimentale sur les techniques et les conditions de navigation précolombiennes dans les Antilles. Ces travaux réalisés dans un cadre scientifique contrôlé et complétés par une analyse des caractéristiques hydrostatiques du canot, nous ont ainsi permis d'obtenir un ensemble de données tout à fait inédites. Elles nous permettent de refonder notre approche de la relation des populations précolombiennes à l'espace archipélique antillais.
The Proceedings of the XXIII Congress of the International Association for Caribbean Archaeology, Antigua, 29 june-3 july 2009

hal-00966520
https://hal.univ-antilles.fr/hal-00966520
https://hal.univ-antilles.fr/hal-00966520/document
https://hal.univ-antilles.fr/hal-00966520/file/ioumoulicou.pdf

Éditeur(s) : HAL CCSD Springer
Résumé : International audience
he search for frequent conceptual links (FCL) is a new network clustering approach that exploits both the network structure and the node properties. While recent works have been focused on the optimisation of the FCL extraction, no study has been conducted on the matching or the intersections between the conceptual links and the classical clustering approach which consists in extracting communities. In this paper, we focus on these two approaches. Our objective is to evaluate the possible relationships existing between FCL and communities to understand how the patterns obtained by each kind of methods may match as well as the useful knowledge resulting from the intersections of these two kinds of knowledge. For this purpose, we propose a set of original measures, based on the notion of homogeneity, assessing the level of shared information between these patterns when they are extracted from the same dataset. The measures are applied on three datasets and demonstrate the importance of considering simultaneously various kinds of knowledge and their intersections.
ISSN: 1869-5450

hal-01312313
https://hal.archives-ouvertes.fr/hal-01312313
DOI : 10.1007/s13278-014-0197-1

Éditeur(s) : HAL CCSD European Geosciences Union
Résumé : International audience
Natural disturbances are the dominant form of forest regeneration and dynamics in unmanaged tropical forests. Monitoring the size distribution of treefall gaps is important to better understand and predict the carbon budget in response to land use and other global changes. In this study, we model the size frequency distribution of natural canopy gaps with a discrete power law distribution. We use a Bayesian framework to introduce and test, using Monte Carlo Markov chain and Kuo–Mallick algorithms, the effect of local physical environment on gap size distribution. We apply our methodological framework to an original light detecting and ranging dataset in which natural forest gaps were delineated over 30 000 ha of unmanaged forest. We highlight strong links between gap size distribution and environment, primarily hydrological conditions and topography, with large gaps being more frequent on floodplains and in wind-exposed areas. In the future, we plan to apply our methodological framework on a larger scale using satellite data. Additionally , although gap size distribution variation is clearly under environmental control, variation in gap size distribution in time should be tested against climate variability.
ISSN: 1726-4170

hal-01590729
https://hal-univ-guyane.archives-ouvertes.fr/hal-01590729
https://hal-univ-guyane.archives-ouvertes.fr/hal-01590729/document
https://hal-univ-guyane.archives-ouvertes.fr/hal-01590729/file/bg-14-353-2017.pdf
DOI : 10.5194/bg-14-353-2017

Éditeur(s) : HAL CCSD Springer Verlag/EDP Sciences
Résumé : International audience
Context : Functional - structural models (FSM) of tree growth have great potential in forestry, but their development, calibration and validation are hampered by the difficulty of collecting experimental data at organ scale for adult trees. Due to their simple architecture and morphological properties, " model plants " such as Cecropia sciadophylla are of great interest to validate new models and methodologies, since exhaustive descriptions of their plant structure and mass partitioning can be gathered. * Aims : Our objective was to develop a model-based approach to analysing the influence of environmental conditions on the dynamics of trophic competition within C. sciadophylla trees. * Methods : We defined an integrated environmental factor that includes meteorological medium-frequency variations and a relative index representing the local site conditions for each plant. This index is estimated based on model inversion of the GreenLab FSM using data from 11 trees for model calibration and 7 trees for model evaluation. * Results : The resulting model explained the dynamics of biomass allocation to different organs during the plant growth, according to the environmental pressure they experienced. * Perspectives : By linking the integrated environmental factor to a competition index, an extension of the model to the population level could be considered.
ISSN: 1286-4560

hal-00780347
https://hal-ecp.archives-ouvertes.fr/hal-00780347
https://hal-ecp.archives-ouvertes.fr/hal-00780347/document
https://hal-ecp.archives-ouvertes.fr/hal-00780347/file/Letort2011AFS.pdf
DOI : 10.1007/s13595-011-0131-x

Éditeur(s) : Communication at the IIFET Conference Tromso 1998
Résumé : (not controled OCR) like most other caribbean islands, martinique suffers a reduction in fisheries resources and is now a net importer of seafood products since no major expansion of aquaculture production has been done. nevertheless, this island has numerous assets for marine aquaculture development : tropical clean waters, developed infrastructures and market channels, financial support for research, training and extension due to its tight political and economic connection with france. red drum is a subtropical fish introduced in martinique in 1985 from the south of usa for aquaculture purposes. from 1987 to 1993, ifremer worked on rearing techniques in martiniquan conditions. once the farming techniques were perfected, questions raised about red drum marketing potential and of economic viability of red drum farms in order to attract investments and entrepreneurs. that is the reason why a market analysis and a financial analysis have been carried out. the results of these studies indicate that martiniquan fish farming could be profitable, due to the rapid build-up of the facilities and to the sho rt production cycles. the good quality of infrastructures in martinique, the high purchase power of the population in comparison with most caribbean islands and the frequent air links with europe are important comparative advantages. the market analysis has revealed a good potential on the domestic market thanks to the development of the supermarkets, but has underlined the price constraint. for the french market too, production costs have to be lowered in order to compete on a market dominated by salmon.

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/1998/acte-2546.pdf
http://archimer.ifremer.fr/doc/00000/2546/

Éditeur(s) : HAL CCSD Wiley
Résumé : Hydraulic habitat models based on the preferences of species for the hydraulic characteristics of their microhabitats are frequently used to evaluate the impact on the habitat of a change in river flow regime. Their application in a tropical insular environment is still limited as little is known about the hydraulic preferences of species. Hydraulic preference models have been developed for 15 taxa (diadromous shrimps and fishes) sampled in 52 rivers in the Caribbean (the French West Indies) and the Indian Ocean (the Reunion island). Five datasets were used and group 8353 samples collected by electrofishing during 320 surveys (reach date) performed between 1999 and 2011. Generalized additive models were used to link variations of taxa density within surveys to the hydraulic characteristics of the microhabitat (velocity, depth and substrate). Hydraulic preferences within each region (Caribbean and Indian Ocean) are significant for most of the taxa and vary little between rivers and surveys. The hydraulic variables explain up to 18.1% (univariate models) and 30.0% (multivariate models) of the deviance of densities within survey. Of the taxa selected, Atya scabra, Macrobrachium heterochirus, Xiphocaris elongata and the Sicydiinae are the most demanding.
ISSN: 1535-1459

hal-01072479
https://hal.archives-ouvertes.fr/hal-01072479
https://hal.archives-ouvertes.fr/hal-01072479/document
https://hal.archives-ouvertes.fr/hal-01072479/file/ly2014-pub00038946.pdf
DOI : 10.1002/rra.2675

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Glioblastoma (GB), the most frequent primary tumor of the central nervous system, remains one of the most lethal human cancers despite intensive researches. Current paradigm in the study of GB has been focused on inter-patient variability and on trying to isolate new classification elements or prognostic factors. Here, using ICPL, a technique for protein relative quantification by mass spectrometry, we investigated protein expression between the four regions of GB on clinically relevant biopsies from 5 patients. We identified 584 non-redundant proteins and 31 proteins were found to be up-regulated in the tumor region compared to the peri-tumoral brain tissue, among which, 24 proteins belong to an interaction network linked to 4 biological processes. The core of this network is mainly constituted of interactions between beta-actin (ACTB) with heat shock proteins (HSP90AA1, HSPA8) and 14-3-3 proteins (YWHAZ, YWHAG, YWHAB). A cluster of three isoforms of the sodium pump α-subunit (ATP1A1, ATP1A2, ATP1A3) was also identified outside this network. The differential expression observed for ACTB and 14-3-3γ was further validated by western blot and/or immunohistochemistry. Our study confirms the identity of previously proposed molecular targets, highlights several functional processes altered in GB such as energy metabolism and synaptic transmission and could thus provide added value to new therapeutic trails.
ISSN: 1874-3919

hal-00877756
https://hal.archives-ouvertes.fr/hal-00877756
DOI : 10.1016/j.jprot.2012.04.034
PUBMED : 22575386

Éditeur(s) : HAL CCSD Vsevolod Gurevich
Résumé : International audience
Chemotherapy is frequently used to treat primary or metastatic cancers, but intrinsic or acquired drug resistance limits its efficiency. Sphingolipids are important regulators of various cellular processes including proliferation, apoptosis, differentiation, angiogenesis, stress, and inflammatory responses which are linked to various aspects of cancer, like tumor growth, neoangiogenesis, and response to chemotherapy. Ceramide, the central molecule of sphingolipid metabolism, generally mediates antiproliferative and proapoptotic functions, whereas sphingosine-1-phosphate and other derivatives have opposing effects. Among the variety of enzymes that control ceramide generation, acid or neutral sphingomyelinases and ceramide synthases are important targets to allow killing of cancer cells by chemotherapeutic drugs. On the contrary, glucosylceramide synthase, ceramidase, and sphingosine kinase are other targets driving cancer cell resistance to chemotherapy. This chapter focuses on ceramide-based mechanisms leading to cancer therapy sensitization or resistance which could have some impacts on the development of novel cancer therapeutic strategies.
Handb Exp Pharmacol

inserm-00871347
http://www.hal.inserm.fr/inserm-00871347
PUBMED : 23563652
DOI : 10.1007/978-3-7091-1511-4_4

Éditeur(s) : Elsevier Science Bv
Résumé : The Var turbiditic system located in the Ligurian Sea (SE France) is an intermediate mud/sand-rich system. The particularity of the Var deep-sea fan is its single channel with abrupt bends and its asymmetric and hyper-developed levee on the right hand side: the Var Sedimentary Ridge. Long-term sediment accumulation on the Var Sedimentary Ridge makes this an ideal target for studying the link between onshore climate change and deep-sea turbidite stratigraphy. This paper focuses on the establishment of the first detailed stratigraphy of the levee, which is used to analyze the timing of overbank deposition throughout the last deglaciation. Main results indicate that high variability in turbidite frequencies and deposition rates along the Var Sedimentary Ridge are determined by two main parameters: 1) the progressive decrease of the levee height controlling the ability of turbidity currents to spill out from the channel onto the levee, and 2) climatic variations affecting the drainage basin, in particular changes in glacial condition since late Last Glacial Maximum to early Holocene. Compared to other deep-water areas, this study confirms the ability of turbiditic systems to record past climatic events on millennial timescales, and underlines the influence of European deglaciation on the observed decrease in turbidite activity in the Var canyon. The presence of a very narrow continental shelf and a single, large channel-levee system makes the Var Sedimentary Ridge a unique example of climate-controlled turbiditic accumulations. (C) 2010 Elsevier B.V. All rights reserved.
Marine Geology (0025-3227) (Elsevier Science Bv), 2011-01 , Vol. 279 , N. 1-4 , P. 148-161

Droits : 2010 Elsevier Ltd All rights reserved.
http://archimer.ifremer.fr/doc/00030/14104/11370.pdf
DOI:10.1016/j.margeo.2010.10.021
http://archimer.ifremer.fr/doc/00030/14104/

Résumé : L’objet de cette thèse est de présenter les spécificités épidémiologiques, étiologiques et thérapeutiques de la pathologie neurovasculaire dans la population noire spécifique que constitue la population martiniquaise. En 1998, l’étude ERMANCIA I a permis de mettre en évidence une surincidence des accidents vasculaires cérébraux (AVC) en Martinique d’environ 40% par rapport à la métropole avec une haute prévalence de l’hypertension artérielle et du diabète. Ces résultats ont participé à la création en 2003 de la 1ère unité neurovasculaire aux Antilles. Le suivi à 5 ans des patients ERMANCIA I a révélé que la moitié était décédée et que 50% des survivants présentaient une démence vasculaire (soit le double des cohortes métropolitaines), probablement favorisé par une microangiopathie cérébrale sous-jacente souvent sévère amplifiant l’impact cognitif de l’AVC. Ce suivi a également permis d’identifier les faiblesses de la prévention secondaire en Martinique avec près de 80% des hypertendus qui restent mal équilibrés justifiant la création en 2006 d’un réseau de prévention. L’efficacité de ce réseau a été évaluée montrant un taux élevé de bon contrôle tensionnel (74% vs 39%, p=0,01) et une morbi-mortalité vasculaire moindre à 2,5 ans (8,3% vs 24%, p<0,001) que chez les patients contrôles. En 2012, ERMANCIA II a permis de révéler une diminution majeure (en moyenne 30%) de l’incidence des AVC dans la population martiniquaise et de la mortalité à 1 mois pour les patients ≤55 ans (20% vs 8%, p=0,03) probablement en raison d’une meilleure implémentation des mesures de prévention primaire et de la prise en charge en UNV respectivement. Nos données ont également permis de décrire certaines spécificités étiologiques des AVC chez les Martiniquais : grande fréquence de l’athérome intracrânien (pour lequel nous apportons des arguments en faveur d’une nouvelle classification), infarctus choroïdiens antérieurs dont nous décrivons le profil évolutif particulier, infarctus lacunaires multiples sévères. Deux étiologies plus « classiques » comme la drépanocytose et les IC sur morsure de serpent sont devenues anecdotiques. En revanche, une dysplasie carotidienne focale, étiologie déjà décrite mais supposée rare , pourrait être responsable d’un tiers des infarctus carotidiens d’origine indéterminée chez les Afro-Caribéens ≤55 ans exposant à un risque élevé de récidive sous traitement antiagrégant (28% à 14 mois), contre aucun pour les patients traités par endartériectomie. Sur le plan thérapeutique, nos résultats sont en faveur d’un surrisque hémorragique de la thrombolyse standard chez les patients martiniquais les plus âgés, probablement en rapport avec un cumul de lésions microangiopathiques plus important. En l’absence de neuroradiologie interventionnelle en Martinique, nos travaux montrent que certains patients avec occlusion artérielle proximale résistante à la thrombolyse IV standard peuvent bénéficier d’un complément de thrombolytique (0,1mg/Kg de tenecteplase). Une étude randomisée est prévue afin de mieux mesurer le potentiel thérapeutique de cette stratégie. Pour conclure, l’intérêt de ces données est que la population martiniquaise partage très probablement beaucoup de ses « particularités » avec d’autres populations noires encore peu décrites et pour lesquelles l’occidentalisation progressive du mode de vie risque d’accentuer le fardeau représenté par les AVC.
Our work presented herein aimed to describe the epidemiological, etiological and therapeutic features of the stroke pathology in the Martinican Afro-Caribbean population. In 1998, the first population-based epidemiological study, ERMANCIA I, showed a 40% greater firstever stroke incidence in Martinique compared to those observed in continental France, with a high prevalence of hypertension and diabetes. These results contributed to the creation, in 2003, of the first stroke unit in the Caribbean area. In the 5_year follow-up study, we found that half of the patients had died and that 50% of survivors were affected from vascular dementia (twice compared with continental French cohorts): this figure was probably favored by severe underlying cerebral microangiopathy that amplified the cognitive impact of stroke. We also identified a failure in the secondary prevention in Martinique, certified by nearly 80% of hypertensive patients still insufficiently controlled. As a result, in 2006, we developed a well-structured stroke prevention network. The efficiency of this network was attested by the high rate of good blood pressure control (74% vs. 39%, p=0.01) and the reduced vascular morbidity and mortality rate (8.3% vs. 24%, p <0.001) after a 30-month period of activity, in comparison with control “historic” patients. In 2012, ERMANCIA II study revealed a 30% reduction of first-ever stroke incidence and a reduced mortality rate at 1 month for patients ≤55 years (8% vs. 20%, p = 0.03), compared to these observed in ERMANCIA I, likely due to improvement of primary stroke prevention and the best stroke unit management at the acute phase, respectively. Based on our etiological data, we underline: 1) the relatively high frequency of symptomatic intracranial atherosclerosis, for which we propose a new definition; 2) the clinic-radiological features of stroke in the anterior choroidal artery; 3) the atypical picture of “malignant” multilacunar syndrome. On the other hand, stroke due to sickle cell disease or “trigonocephale” snakebite were only anecdotal. However, we found that carotid-bulb atypical fibromuscular dysplasia (CAFD), a very unusual previously described cause of stroke, could be responsible for up to the third of carotidterritory stroke of so-called undetermined etiology among patients ≤55 years. In addition, the relatively high rate of recurrence under antiplatelet (28% at 14 months), was dramatically reduced by endarterectomy in patients with CAFD. From a therapeutic point of view, our results showed an excess rate of post-thrombolysis symptomatic intracerebral hemorrhages in older patients, a figure probably linked to the severe underlying hypertension-triggered cerebral microangiopathy. Owing to the lack of neurointerventionnal option in Martinique, we tested a new therapeutic strategy in patients with a proximal arterial occlusion not responsive to standard IV thrombolysis, consisting in an additional administration of IV tenecteplase, 0.1mg/kg. Our preliminary results were promising, leading us to plan a randomized study. Finally, most of the characteristics of stroke in this Afro-Caribbean population are probably shared by the majority of black people. Thus, our results could have a universal impact in the understanding of stroke burden in blacks.

http://www.theses.fr/2015AGUY0909/document