Éditeur(s) : EDP Sciences
Résumé : Lessons for the future from two development projects in aquaculture in the French overseas territories. Numerous research and development projects have been launched since the seventies in the French overseas territories. Their aim was to foster new activities in agriculture based on local productions for local markets, notably in the French West Indies (FWI). In this paper we analyze two development projects on the rearing of giant freshwater prawn, one in the FWI and the other in French Guyana, over twenty years after their launching. The purpose of these compared studies is twofold: first to try to understand why a set of relevant technical innovations ended in failure 15 years later; second to identify recommendations in terms of methodology in order to diminish risks of mistakes or failure for future projects. To reach this goal we followed two approaches. A first analysis is based on a set of three criteria: social acceptability, legitimacy and time planning. The second analysis, justified by the subjective need for an explanatory tool, is based on the actor-network theory. The results show that beyond the levels of political support and financial investment and support the three key criteria for success are: (i) reactivity of the decision-makers, notably when markets change, (ii) quality of leadership transfer between the launching phase and the stabilized phase, and (iii) capacity of the decision-makers to take into account the concrete consequences of the various scenarios. Regarding this third criterion, our analysis suggests that the scenario of full technical success needs to be explored, notably in terms of economic sustainability. The integration of these two types of analyses into an ex-ante frame should contribute to reducing risks of failure in similar development projects.
De nombreux projets d’aquaculture ont été menés depuis les années 1970 dans les territoires et départements français d’outre-mer. L’objectif était de diversifier l’agriculture avec des productions destinées au marché local comme aux Antilles, ou à l’exportation comme en Guyane. L’étude s’intéresse au bilan de deux projets d’élevage de la crevette tropicale d’eau douce aux Antilles et en Guyane, plus de vingt ans après leur lancement. L’objectif est de comprendre comment des innovations technologiques pertinentes ont conduit à deux échecs sur le moyen terme et de tirer des recommandations de méthode afin de réduire les risques d’erreurs ultérieures. Pour cela, deux cadres d’analyse sont mobilisés : le premier s’appuie sur les concepts de temporalité, légitimité et acceptabilité ; le second, motivé par la recherche subjective de cadres explicatifs, emprunte la vision de la théorie de l’acteur-réseau. Les trois déterminants majeurs du succès ou de l’échec se révèlent être la réactivité des responsables face aux problèmes d’adaptation à l’évolution des marchés, la qualité du transfert du leadership lors du passage de la phase de lancement à la phase de croisière et enfin la capacité de prendre en compte dès le départ les conséquences des scénarios d’évolution du projet, y compris la réussite technique. Une capacité d’intégration de ces types d’analyse, dans un cadre ex ante, devrait permettre de réduire les risques d’échec dans des projets de développement similaires à venir.
Natures Sciences et Sociétés (1240-1307) (EDP Sciences), 2013-12 , Vol. 21 , N. 4 , P. 400-415

Droits : NSS-Dialogues, EDP Sciences 2014
http://archimer.ifremer.fr/doc/00187/29784/28242.pdf
DOI:10.1051/nss/2014004
http://archimer.ifremer.fr/doc/00187/29784/

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
These last years, many analysis methods have been proposed to extract knowledge from social networks. As for the traditional data mining domain, these network-based approaches can be classified according to two main families. The approaches based on predictive modelling, which encompass the techniques that analyse current and historical facts to make predictive assumptions about future or unknown events. The approaches based on descriptive modelling, which cover the set of techniques that aim to summarize the data by identifying some relevant features in order to describe how things organize and actually work. In this paper, we review the main descriptive modelling methods of social networks and show for each of them the resulting useful knowledge on a running example. We particularly emphasize on the most recent methods that combine information available on both the network structure and the node attributes in order to provide original description models taking into account the context.
EISSN: 1877-0509

hal-01312383
https://hal.univ-antilles.fr/hal-01312383
DOI : 10.1016/j.procs.2015.05.505

Éditeur(s) : HAL CCSD Wiley
Résumé : International audience
While the effects of deforestation and habitat fragmentation on parasite prevalence or richness are well investigated, host-parasite networks are still understudied despite their importance in understanding the mechanisms of these major disturbances. Because fragmentation may negatively impact species occupancy, abundance and co-occurrence, we predict a link between spatiotemporal changes in habitat and the architecture of host-parasite networks. For this, we used an extensive data set on 16 rodent species and 29 helminth species from seven localities of South-East Asia. We analysed the effects of rapid deforestation on connectance and modularity of helminth-parasite networks. We estimated both the degree of fragmentation and the rate of deforestation through the development of land uses and their changes through the last 20 to 30years in order to take into account the dynamics of habitat fragmentation in our statistical analyses. We found that rapid fragmentation does not affect helminth species richness per se but impacts host-parasite interactions as the rodent-helminth network becomes less connected and more modular. Our results suggest that parasite sharing among host species may become more difficult to maintain with the increase of habitat disturbance.
ISSN: 0021-8790

hal-01355307
https://hal.archives-ouvertes.fr/hal-01355307
DOI : 10.1111/1365-2656.12368
IRD : fdi:010064927

Éditeur(s) : HAL CCSD BioMed Central
Résumé : International audience
Cell proliferation is a hallmark of cancer and depends on complex signaling networks that are chiefly supported by protein kinase activities. Therapeutic strategies have been used to target specific kinases but new methods are required to identify combined targets and improve treatment. Here, we propose a small interfering RNA genetic screen and an integrative approach to identify kinase networks involved in the proliferation of cancer cells. The functional siRNA screen of 714 kinases in HeLa cells identified 91 kinases implicated in the regulation of cell growth, most of them never being reported in previous whole-genome siRNA screens. Based on gene ontology annotations, we have further discriminated between two classes of kinases that, when suppressed, result in alterations of the mitotic index and provoke cell-cycle arrest. Extinguished kinases that lead to a low mitotic index mostly include kinases implicated in cytosolic signaling. In contrast, extinguished kinases that result in a high mitotic index mostly include kinases implicated in cell division. By mapping hit kinases in the PhosphPOINT phosphoprotein database, we generated scale-free networks consisting of 449 and 661 protein-protein interactions for kinases from low MI and high MI groups, respectively. Further analyses of the kinase interactomes revealed specific modules such as FER- and CRKL-containing modules that connect three members of the epidermal growth factor receptor (EGFR) family, suggesting a tight control of the mitogenic EGF-dependent pathway. Based on experimental studies, we confirm the involvement of these two kinases in the regulation of tumor cell growth. Based on a combined approach of large kinome-wide siRNA screens and ontology annotations, our study identifies for the first time two kinase groups differentially implicated in the control of cell proliferation. We further demonstrate that integrative analysis of the kinase interactome provides key information which can be used to facilitate or optimize target design for new therapeutic strategies. The complete list of protein-protein interactions from the two functional kinase groups will provide a useful database for future investigations.
ISSN: 1471-2164

hal-01118475
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01118475
DOI : 10.1186/1471-2164-15-1169
PUBMED : 25540073

Éditeur(s) : HAL CCSD IGI Global
Résumé : International audience
The social behavior of individuals is an important factor of the transmission and the evolution of many diseases. As such, epidemic studies have attempted to integrate social aspects in dissemination modeling. Since the pioneering works of Klovdahl on AIDS in 1985, epidemiological investigations and interventions increasingly focus on social networks. Significant factors of the transmission and outbreak of many infectious diseases are the structure and nature of human interactions. Network-based modeling approaches have found various applications in epidemiology as a simple yet efficient way to represent the complexity of human relationships implicated in dissemination processes. However, most results have been obtained by considering social networks as steady stage structures. Evolving networks have not been explored. The objective is first to give an overview of network-based modeling attempts in epidemiology to analyze and understand the dissemination processes with an emphasis on dynamic networks. The authors approach is designed to understand the impact of social links dynamics on epidemic spread. The authors present the results obtained by combining network evolution patterns (link creation and deletion) and a typical epidemic model. The speed of link dynamics and the infection time strongly influence the occurrence and value of the epidemic peak.
ISSN: 1947-8186

hal-00700105
https://hal.archives-ouvertes.fr/hal-00700105
DOI : 10.4018/jismd.2012070103

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
From outcrops located in Provence (South-East France), we describe the distribution, the microstructures, and the petrophysical properties of deformation band networks related to both contractional and extensional tectonic events. In contraction, pervasively distributed networks of reverse-sense compactional shear bands are observed in all folded sand units of the foreland, whereas localized networks of clustered reverse-sense shear bands are only observed close to a large-scale thrust. In extensional setting, networks of clustered normal-sense shear bands are generally observed adjacent to map-scale faults (100 m–10 km scale), although some randomly distributed bands are also observed between these faults. Normal-sense cataclastic faults, i.e. zone of deformation bands containing a localized slip-surface, are also observed to be restricted to sand units, suggesting that faults initiated in the sands during extension, but not during contraction. Shear bands and faults show cataclastic microstructures with high-permeability reduction whereas compactional shear bands show crush microbreccia or protocataclastic microstructures with moderate permeability reduction. This basin-scale analysis underlines the major role of tectonic settings (thrust-fault versus normal-fault andersonian-stress regime) and the influence of inherited large-scale faults on the formation/localization of low-permeability shear bands. We also provide a geometrical analysis of the band network properties (spacing, thickness, shear/compaction ratio, degree of cataclasis, petrophysical properties) with respect to the median grain size, porosity and grain sorting of host sand. This analysis suggests that grain size, although less important than stress-state conditions and the presence of large-scale faults, has a non-negligible effect on band network geometry. No correlations are observed between the grain sorting, porosity and band network geometry.
ISSN: 0264-8172

hal-01116421
https://hal.archives-ouvertes.fr/hal-01116421
DOI : 10.1016/j.marpetgeo.2013.12.020

Éditeur(s) : Wiley-blackwell Publishing, Inc
Résumé : Seagrasses structure some of the world's key coastal ecosystems presently in decline due to human activities and global change. The ability to cope with environmental changes and the possibilities for shifts in distribution range depend largely on their evolvability and dispersal potential. As large-scale data usually show strong genetic structure for seagrasses, finer-grained work is needed to understand the local processes of dispersal, recruitment and colonization that could explain the apparent lack of exchange across large distances. We aimed to assess the fine-grained genetic structure of one of the most important and widely distributed seagrasses, Zostera marina, from seven meadows in Brittany, France. Both classic population genetics and network analysis confirmed a pattern of spatial segregation of polymorphism at both regional and local scales. One location exhibiting exclusively the variety 'angustifolia' did not appear more differentiated than the others, but instead showed a central position in the network analysis, confirming the status of this variety as an ecotype. This phenotypic diversity and the high allelic richness at nine microsatellites (2.33-9.67 alleles/locus) compared to levels previously reported across the distribution range, points to Brittany as a centre of diversity for Z. marina at both genetic and phenotypic levels. Despite dispersal potential of several 100 m, a significant pattern of genetic differentiation, even at fine-grained scale, revealed 'genetic patchiness'. Meadows seem to be composed of a mosaic of clones with distinct origins in space and time, a result that calls into question the accuracy of the concept of populations for such partially clonal species.
Molecular Ecology (0962-1083) (Wiley-blackwell Publishing, Inc), 2010-06 , Vol. 19 , N. 12 , P. 2394-2407

Droits : 2010 Blackwell Publishing Ltd
http://archimer.ifremer.fr/doc/00006/11690/8499.pdf
DOI:10.1111/j.1365-294X.2010.04649.x
http://archimer.ifremer.fr/doc/00006/11690/

Éditeur(s) : HAL CCSD American Meteorological Society
Résumé : Global positioning system (GPS) data from a dense network have been used for the analysis of the diurnal cycle of water vapor over Marseille, France, during the second intensive observation period (IOP2; 21–26 June 2001) of the Expérience sur Sites pour Contraindre les Modèles de Pollution Atmosphérique et de Transport d'Emission (ESCOMPTE) field experiment. Both tomographic analyses and integrated water vapor (IWV) contents from GPS have been used, in addition to wind profiler data and surface observations. Tomographic analysis of data from the dense GPS network and radiosondes provided the continuous temporal evolution of the vertical distribution of water vapor over the city of Marseille. The city is located on the shore of the Mediterranean Sea in southeastern France and is often under the influence of sea-breeze effects. Two different layers of breeze circulation are identified: a shallow sea breeze, blowing perpendicular to the local coastline, and a deep sea breeze, induced by the regional temperature gradient between sea and land. The origin of water vapor is shown to be mainly due to the advection of marine moist air by these sea-breeze circulations. However, the diurnal cycle of water vapor over Marseille is strongly influenced by the synoptic situation, which changes during the IOP2 (between a northerly mistral in the early stage of the IOP and an easterly wind at the end). It is shown that vertical profiles from tomographic analyses (combined with wind profiler data) allow for a proper interpretation of the diurnal cycle observed in IWV. Two-dimensional maps of IWV are also shown to complement the description of the horizontal advection of moisture by the different circulation regimes.
ISSN: 1558-8424

hal-00273624
https://hal.archives-ouvertes.fr/hal-00273624
https://hal.archives-ouvertes.fr/hal-00273624/document
https://hal.archives-ouvertes.fr/hal-00273624/file/drJAM_cycle_diurne_GPS_rev1.pdf
DOI : 10.1175/JAM2450.1

Éditeur(s) : HAL CCSD Oxford University Press (OUP)
Résumé : International audience
BACKGROUND: Mammalian spermatogenesis is a process that involves a complex expression program in both somatic and germ cells present in the male gonad. A number of studies have attempted to define the transcriptome of male meiosis and gametogenesis in rodents and primates. Few human transcripts, however, have been associated with testicular somatic cells and germ cells at different post-natal developmental stages and little is known about their level of germline-specificity compared with non-testicular tissues. METHODS: We quantified human transcripts using GeneChips and a total of 47 biopsies from prepubertal children diagnosed with undescended testis, infertile adult patients whose spermatogenesis is arrested at consecutive stages and fertile control individuals. These results were integrated with data from enriched normal germ cells, non-testicular expression data, phenotype information, predicted regulatory DNA-binding motifs and interactome data. RESULTS: Among 3580 genes for which we found differential transcript concentrations in somatic and germ cells present in human testis, 933 were undetectable in 45 embryonic and adult non-testicular tissues, including many that were corroborated at protein level by published gene annotation data and histological high-throughput protein immunodetection assays. Using motif enrichment analyses, we identified regulatory promoter elements likely involved in germline development. Finally, we constructed a regulatory disease network for human fertility by integrating expression signals, interactome information, phenotypes and functional annotation data. CONCLUSIONS: Our results provide broad insight into the post-natal human testicular transcriptome at the level of cell populations and in a global somatic tissular context. Furthermore, they yield clues for genetic causes of male infertility and will facilitate the identification of novel cancer/testis genes as targets for cancer immunotherapies.
ISSN: 0268-1161

hal-00877243
https://hal.archives-ouvertes.fr/hal-00877243
DOI : 10.1093/humrep/des301
PUBMED : 22926843

Éditeur(s) : HAL CCSD Oxford University Press (OUP)
Résumé : International audience
Motivation: Gene fusion is an important evolutionary process. It can yield valuable information to infer the interactions and functions of proteins. Fused genes have been identified as non-transitive patterns of similarity in triplets of genes. To be computationally tractable, this approach usually imposes an a priori distinction between a dataset in which fused genes are searched for, and a dataset that may have provided genetic material for fusion. This reduces the `genetic space' in which fusion can be discovered, as only a subset of triplets of genes is investigated. Moreover, this approach may have a high-false-positive rate, and it does not identify gene families descending from a common fusion event. Results: We represent similarities between sequences as a network. This leads to an efficient formulation of previous methods of fused gene identification, which we implemented in the Python program FusedTriplets. Furthermore, we propose a new characterization of families of fused genes, as clique minimal separators of the sequence similarity network. This well-studied graph topology provides a robust and fast method of detection, well suited for automatic analyses of big datasets. We implemented this method in the C++ program MosaicFinder, which additionally uses local alignments to discard false-positive candidates and indicates potential fusion points. The grouping into families will help distinguish sequencing or prediction errors from real biological fusions, and it will yield additional insight into the function and history of fused genes.
ISSN: 1367-4803

hal-01544795
https://hal.archives-ouvertes.fr/hal-01544795
DOI : 10.1093/bioinformatics/btt049

Éditeur(s) : Université des Antilles Études caribéennes
Résumé : Sur fond de crise du tourisme au Nord, de la globalisation de l’économie et de l’accélération des mobilités, une évolution des formes de développement touristiques semble à l’œuvre dans les confins géographiques. Dans certains territoires touristiques du fait de conflits dans l’usage des ressources naturelles, des pratiques récréatives alternatives émergent qui combinent une logique économique avec des préoccupations socio-environnementales.Notre article analyse l’apparition du tourisme scientifique dans la région « non-touristique » de Aysén, en Patagonie chilienne. Des acteurs d’un territoire se mobilisent selon des pôles culturels et des axes thématiques autour de projets pilotes, de recherche expérientielle et de médiations scientifiques innovantes. Sur ce front pionnier, un réseau informel d’acteurs coordonne ses actions pour aborder les problématiques sociales et environnementales de leur territoire. Opérateurs et prestataires pour le tourisme scientifique créent de manière participative une offre originale. Un système touristique alternatif, axé sur la protection de l’environnement, de la culture et des dynamiques sociales de la communauté d’accueil, favorise l’acquisition et le partage de savoirs entre scientifiques, acteurs locaux et visiteurs.Le tourisme scientifique s’inscrit-il dans une évolution globale des pratiques touristiques ? En proposant de dépasser les frontières, entre activités récréatives et le travail, de lieux de vie et de loisir, il apparaît comme l’expression d’un « après-tourisme ». L’hybridation des pratiques, une approche scientifique associée à l’esprit de la découverte inhérent au voyage, semble pouvoir relever des défis sociétaux liés à l’essor d’un tourisme globalisé. Alors que le tourisme est pensé depuis longtemps en termes de transfert de compétences, de modèles et d’ingénierie du Nord vers le Sud, une périphérie propose de nouveaux cadres de pensée, d’action et de participation qui renouvellent le sens du voyage.
In the context of a tourism crisis in the north, a globalized economy and an increase of mobility, a change in the forms of tourism development seems to occur in peripheral areas. In some tourism areas and due to conflicts over the use of natural resources, alternative recreational practices arise that combine economic needs and socio-environmental concerns.Our article analyzes the appearance of scientific tourism in the "non-tourist" region of Aysén, in Chilean Patagonia. Actors of a territory unite according to specific cultural poles and thematic axes through experiential research and innovative scientific mediation pilot projects. On this pioneer front, an informal network of stakeholders coordinates its actions to address the social and environmental issues of their territory. Operators and service providers for scientific tourism create an innovative offer in a participatory process. An alternative tourism system, focused on protecting the environment, the culture and social dynamics of the host community, promotes the acquisition and sharing of knowledge between scientists, local actors and visitors.Is scientific tourism part of a global evolution of tourism practices? By proposing to go beyond established boundaries, of recreational activities and work, everyday places and leisure areas, it appears as the expression of an “After-Tourism”. The hybridization of practices, a scientific approach associated with the spirit of the discovery inherent of the travel experience, seems to respond to the challenges of the community confronted to the rise of a globalized tourism. While tourism has always been thought of in terms of transfer of skills, models and engineering from the North to the South, a periphery offers new frameworks of thought, action and participation that renew the meaning of travel.
En un escenario de crisis del turismo en los países desarrollados, de la globalización de la economía y del incremento de las movilidades, una evolución de las formas de desarrollo del turismo parece estar en marcha en los confines geográficos. En ciertos territorios turísticos, debido a los conflictos de uso de los recursos naturales, prácticas recreativas alternativas surgen que combinan una lógica económica con preocupaciones socio-ambientales.El presente artículo analiza el surgimiento del turismo científico en la región “no-turística” de Aysén en la Patagonia chilena. Actores del territorio se unen según polos y temáticas científicas, a través de proyectos pilotos, de investigación experiencial y mediaciones científicas innovadoras. En este frente pionero, una red informal se organiza para abordar las problemáticas sociales y ambientales de su territorio. Operadores y proveedores de servicios para el turismo científico crean de manera participativa una oferta novedosa. Un sistema turístico alternativo, basado en el cuidado del medio ambiente, de la cultura y de las dinámicas sociales del comunidad de acogida, favorece la adquisición y el intercambio de conocimientos entre científicos, actores locales y visitantes. ¿Será la aparición del turismo científico la expresión de una evolución global de las practicas turísticas? Al invitar a que sean sobrepasadas las fronteras, entre actividades recreativas y el trabajo, lugares de vida y sitios de esparcimiento, este se presenta como un “Pos-Turismo”. La hibridación de las prácticas, una aproximación científica asociada al espíritu de descubrimiento inherente del viaje, parece poder resolver los desafíos de nuestras sociedades vinculados al auge de un turismo globalizado. Cuando el turismo suele ser pensado desde hace mucho, como un proceso de transferencia de capacidades, de modelos y de ingenierías, del Norte hacia el Sur, una periferia propone nuevos marcos conceptuales, de acción y de participación, que renuevan el sentido del viaje.
Patagonie

Droits : info:eu-repo/semantics/openAccess
urn:doi:10.4000/etudescaribeennes.11169
http://journals.openedition.org/etudescaribeennes/11169

Éditeur(s) : HAL CCSD BioMed Central
Résumé : International audience
Background: Increasingly, similarity networks are being used for evolutionary analyses of molecular datasets. These networks are very useful, in particular for the analysis of gene sharing, lateral gene transfer and for the detection of distant homologs. Currently, such analyses require some computer programming skills due to the limited availability of user-friendly freely distributed software. Consequently, although appealing, the construction and analyses of these networks remain less familiar to biologists than do phylogenetic approaches. Results: In order to ease the use of similarity networks in the community of evolutionary biologists, we introduce a software program, EGN, that runs under Linux or MacOSX. EGN automates the reconstruction of gene and genome networks from nucleic and proteic sequences. EGN also implements statistics describing genetic diversity in these samples, for various user-defined thresholds of similarities. In the interest of studying the complexity of evolutionary processes affecting microbial evolution, we applied EGN to a dataset of 571,044 proteic sequences from the three domains of life and from mobile elements. We observed that, in Borrelia, plasmids play a different role than in most other eubacteria. Rather than being genetic couriers involved in lateral gene transfer, Borrelia's plasmids and their genes act as private genetic goods, that contribute to the creation of genetic diversity within their parasitic hosts. Conclusion: EGN can be used for constructing, analyzing, and mining molecular datasets in evolutionary studies. The program can help increase our knowledge of the processes through which genes from distinct sources and/or from multiple genomes co-evolve in lineages of cellular organisms.
ISSN: 1471-2148

hal-01544799
https://hal.archives-ouvertes.fr/hal-01544799
DOI : 10.1186/1471-2148-13-146

Éditeur(s) : Pêche thonière et dispositifs de concentration de poissons, Caribbean-Martinique, 15-19 Oct 1999
Résumé : Abidjan is the biggest fishing harbour of tropical tunas in the Gulf of Guinea (around 100 000 mt per year). Three canneries work on four species (yellowfin, skipjack, bigeye and albacore). Small size tuna, minor tuna and by-catches are refused by the canneries and are sold on the local market fish. It is the only part of the industrial purse seine catches directly sold in Abidjan. Since 1990, fishing operations on schools of tuna associated with artificial drifting FADs has become widespread. Log fishery allow to catch a majority of small tunas, and generates by-catches of various other pelagic species associated to the logs. The landed amounts of local market fish have increased: from 8 500 Mt per year estimated between 1987 and 1990, 21 000 Mt is reached between 1991 and 1993. Since 1994, controls have been carried out by French fishing companies. A sampling scheme allows us to analyse precisely the landings since 1998. From an interdisciplinary approach, we study the socio-economic role of this local fish market, especially the links between the different actors on this market, and we analyse his impact on fishing strategies by identifying the distribution networks (actors, prices, profit) and estimating the turnovers connected to this sector.

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/00042/15318/12642.pdf
http://archimer.ifremer.fr/doc/00042/15318/

Éditeur(s) : Amer Geophysical Union
Résumé : After the January 12, 2010, Haiti earthquake, we deployed a mainly offshore temporary network of seismologic stations around the damaged area. The distribution of the recorded aftershocks, together with morphotectonic observations and mainshock analysis, allow us to constrain a complex fault pattern in the area. Almost all of the aftershocks have a N-S compressive mechanism, and not the expected left-lateral strike-slip mechanism. A first-order slip model of the mainshock shows a N264 degrees E north-dipping plane, with a major left-lateral component and a strong reverse component. As the aftershock distribution is sub-parallel and close to the Enriquillo fault, we assume that although the cause of the catastrophe was not a rupture along the Enriquillo fault, this fault had an important role as a mechanical boundary. The azimuth of the focal planes of the aftershocks are parallel to the north-dipping faults of the Transhaitian Belt, which suggests a triggering of failure on these discontinuities. In the western part, the aftershock distribution reflects the triggering of slip on similar faults, and/or, alternatively, of the south-dipping faults, such the Trois-Baies submarine fault. These observations are in agreement with a model of an oblique collision of an indenter of the oceanic crust of the Southern Peninsula and the sedimentary wedge of the Transhaitian Belt: the rupture occurred on a wrench fault at the rheologic boundary on top of the under-thrusting rigid oceanic block, whereas the aftershocks were the result of the relaxation on the hanging wall along pre-existing discontinuities in the frontal part of the Transhaitian Belt. Citation: Mercier de Lepinay, B., et al. (2011), The 2010 Haiti earthquake: A complex fault pattern constrained by seismologic and tectonic observations, Geophys. Res. Lett., 38, L22305, doi:10.1029/2011GL049799.
Geophysical Research Letters (0094-8276) (Amer Geophysical Union), 2011-11 , Vol. 38 , N. L22305 , P. 7 p.

Droits : 2011 by the American Geophysical Union
http://archimer.ifremer.fr/doc/00054/16557/14071.pdf
DOI:10.1029/2011GL049799
http://archimer.ifremer.fr/doc/00054/16557/

Éditeur(s) : HAL CCSD Royal Society, The
Résumé : International audience
Individuals can play different roles in maintaining connectivity and socialcohesion in animal populations and thereby influence population robustnessto perturbations.We performed a social network analysis in a reef shark populationto assess the vulnerability of the global network to node removal underdifferent scenarios. We found that the network was generally robust to theremoval of nodes with high centrality. The network appeared also highlyrobust to experimental fishing. Individual shark catchability decreased as afunction of experience, as revealed by comparing capture frequency and sitepresence. Altogether, these features suggest that individuals learnt to avoidcapture, which ultimately increased network robustness to experimentalcatch-and-release. Our results also suggest that some caution must be takenwhen using capture–recapture models often used to assess population sizeas assumptions (such as equal probabilities of capture and recapture) maybe violated by individual learning to escape recapture.
EISSN: 1471-2954

hal-01561754
https://hal-univ-perp.archives-ouvertes.fr/hal-01561754
DOI : 10.1098/rsbl.2016.0824

Éditeur(s) : HAL CCSD Springer
Résumé : International audience
Traditional network generation models aim to replicate global structural properties observed on various real-world networks through synthetic link formation mechanisms such as triadic closure or preferential attachment. Nowadays, the large amount of data available allow to study more precisely the link formation processes and to compare models with real situations. In this work, we analyze the network formed by the communication activities of the users of a telephony operator for studying the link formation process. Our goal is to identify the underlying formation mechanisms and checking if they match those proposed in traditional models. Indeed, the communications emitted and received by users are strong indicators for understanding the underlying patterns of the link formation process and highlighting how some individual properties induce the formation process in such a network. In a first study conducted at a global level, we show that the traditional mechanisms commonly used in network generation models cannot reproduce alone the link formation in this network. In a second study, we adopt a new point of view and analyze locally the link formation process by searching for correlations between some user attributes and the formation of the new links. The results obtained show that a very strong percentage of new links are formed between individuals with strong similarity.
ISSN: 1869-5450

hal-01312310
https://hal.univ-antilles.fr/hal-01312310
DOI : 10.1007/s13278-015-0304-y

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
A dense, local network of 30 geodetic markers covering a 50 × 60 km2 area in the southwestern European Alps (Briançon region) has been temporarily surveyed in 1996, 2006 and 2011 by GPS. The aim is to measure the current deformation in this seismically active area. The study zone is characterized by a majority of extensional and dextral focal mechanisms, along north–south to N160 oriented faults. The combined analysis of the three measurement campaigns over 15 years and up to 16 years of permanent GPS data from the French RENAG network now enables to assess horizontal velocities below 1 mm/year within the local network. The long observation interval and the redundancy of the dense campaign network measurement help to constrain a significant local deformation pattern in the Briançon region, yielding an average E–W extension of 16 ± 11 nanostrain/year. We compare the geodetic deformation field to the seismic deformation rate cumulated over 37 years, and obtain good coherencies both in amplitude and direction. Moreover, the horizontal deformation localized in the Briançon region represents a major part of the Adriatic-European relative plate motion. However, the average uplift of the network in an extensional setting needs the presence of buoyancy forces in addition to plate tectonics.
ISSN: 0264-3707

hal-01119724
https://hal.archives-ouvertes.fr/hal-01119724
DOI : 10.1016/j.jog.2015.02.001

Éditeur(s) : HAL CCSD
Résumé : International audience
In this work, we have led an analysis of the error of different global solar radiation prediction models according to the global solar radiation variability. Different predictions models where performed such as machine learning techniques (Neural Networks, Gaussian processes and support vector machines) in order to forecast the Global Horizontal solar Irradiance (GHI). We also include in this study a simple linear autoregressive (AR) model as well as two naive models based on persistence of the GHI and persistence of the clear sky index (denoted herein scaled persistence model). The models are calibrated and tested with data from three 3 French islands: Corsica (42.15°N ; 9.08°E), Guadeloupe (16.25°N ; 61.58°W) and Reunion (21.15°S ; 55.5°E). Guadeloupe and Reunion are located in a subtropical climatic zone whereas Corsica is in a tempered climatic zone. Hence the global solar radiation variation differs significantly. The output error of the different models was quantified by the nRSME. In order to quantify the influence of the global solar radiation variability on the forecasting models error we performed a classification of typical days according to different typical days. Each class of typical day is defined by a variation of global solar radiation rate. For each class and for each location, the selected forecasting models where performed and the error was quantified. With this analysis a global solar radiation forecasting models can be selected according to the location, the global solar radiation fluctuations and hence the meteorological conditions. INTRODUCTION Large and frequent variations of solar radiation can be observed in tropical climates with amplitudes reaching 800 W/m² and occurring within a short time interval, from few seconds to few minutes, according to the geographical location. Such fluctuations can be due for example to the dynamic of clouds which can be very complex and depend on cloud type, size, speed and spatial distribution and, more generally, due to some specific local meteorological conditions. Thus, the solar energy forecasting, a process used to predict the amount of solar energy available in the current and near terms, might be a difficult task. Some of the best predictors found in literature are Autoregressive and moving average (ARMA) [5,7,8], Bayesian inferences [9,10], Markov chains [11], k-Nearest-Neighbors predictors [12] or artificial intelligence techniques as the Artificial Neural Network (ANN) [9-11]. Although these methodologies are potentially good in many areas, we observed in our previous studies on global radiation prediction [9,13,14] that the simple model based on the persistence of the clear sky index gives often very good results with acceptable errors [15] for short term forecasting time horizon (<= 1 hour). The goal of this paper is to determinate the influence of solar radiation variability regarding different classes of days on the expected error provided by different forecasting methods that the modeller can possibly implement. The paper is organized as follow: Section 2 describes the data we have used. Section 3 exposes the classification methodology and the results obtained for the three studied locations. In the two following sections, the forecasting methods are exposed and then 3 the errors on the forecasting results for each location and for each class are exposed.
The Third Southern African Solar Energy Conference (SASEC2015)
Kruger National Park, South Africa

Droits : info:eu-repo/semantics/OpenAccess
hal-01099487
https://hal.archives-ouvertes.fr/hal-01099487
https://hal.archives-ouvertes.fr/hal-01099487/document
https://hal.archives-ouvertes.fr/hal-01099487/file/article%20SASEC.pdf

Éditeur(s) : HAL CCSD American Association of Petroleum Geologists
Résumé : In reservoir engineering, hydrodynamic properties can be estimated from downhole electrical data using heuristic models (e.g., Archie and Kozeny-Carman's equations) relating electrical conductivity to porosity and permeability. Although proven to be predictive for many sandstone reservoirs, the models mostly fail when applied to carbonate reservoirs that generally display extremely complex pore network structures. In this article, we investigate the control of the three-dimensional (3-D) geometry and morphology of the pore network on the electrical and flow properties, comparing core-scale laboratory measurements and 3-D x-ray microtomography image analysis of samples from a Miocene reefal carbonate platform located in Mallorca (Spain). The results show that micrometer- to centimeter-scale heterogeneities strongly influence the measured macroscopic physical parameters that are then used to evaluate the hydrodynamic properties of the rock, and therefore, existing models might not provide accurate descriptions because these heterogeneities occur at scales smaller than those of the integration volume of the borehole geophysical methods. However, associated with specific data processing, 3-D imagery techniques are a useful and probably unique mean to characterize the rock heterogeneity and, thus, the properties variability.
ISSN: 0149-1423

hal-00950066
https://hal.archives-ouvertes.fr/hal-00950066
DOI : 10.1306/05221312134

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
A large sand injectite network is very well exposed in the area of Bevons, Southeast France. The associated sandstone turbiditic channel–fill and the host marls are the Aptian–Albian rocks of the Vocontian Basin. The sand injection network is composed of dykes, sills and sedimentary laccoliths ranging in thickness from mm to pluri–m. The dykes and sills have vertical and horizontal lengths of up to and over 100 m and 1 km, respectively. Outcrop observations show that the architecture and morphology of the sand injectites in the marls is governed by the local stress field during injection, pre–existing faults, the host–rock lithology, compaction, and distance to the potential sand source(s). The main set of dykes is oriented N50–60° perpendicular to the minimum compressive stress σ3 during sand injection. Two other sets of dykes are intruded along pre–existing syn–sedimentary faults oriented N140–150° (set 2) and N90° (set 3) during the Apto–Cenomanian interval. Sills and dykes thin laterally away from their potential sand sources and thin laterally away from them. The vertical thickness variations of the dykes and wings are more complex, as thinning away from the sand sources is often compensated by thickening toward the palaeo–surface. Based on field observations and measurements, we characterized the 3D architecture of the sand injectites and showed that the injectites probably formed due to a forceful injection from an overpressured sand body sealed by low–permeability lithologies.
ISSN: 0191-8141

hal-01243488
https://hal.archives-ouvertes.fr/hal-01243488
DOI : 10.1016/j.jsg.2015.07.001