Éditeur(s) : HAL CCSD
Résumé : International audience
The French education system remains highly centralized and only allows limited local adaptations for overseas territories. For example, if some laws (the last in 2013) allow the use of regional languages (e.g. Creole in the French West Indies) when they constitute a relevant contribution to the teaching, many official texts remain mainly based on the geographical, economical, historical, environment of the French mainland. We focus on some French BTS (Brevet de Technicien Supérieur / Advanced Technician Certificate), namely tourism and assistant manager, which are two important diplomas for the local development and in which microeconomic and management sciences plays a great part. The French BTS is a professional diploma prepared in two years after the “baccalauréat”, with national programs and evaluation criteria. The successful candidates are supposed to be immediately employable, especially in their local geographical environment. Thus, there exists a paradox between the national definition of the diploma and the local contexts of teaching. We discuss how teachers concretely deal with this situation on a day-to-day basis. Our hypothesis is that they act pragmatically, using their practical pedagogical content knowledge, without theoretical support for their action. In order to verify this hypothesis, we have conducted semi-structured interview with Guadeloupian teachers of the two aforementioned BTS. The main results shows that teachers adapt the national framework of the diploma, essentially by using local examples. This can be called a weak contextualization of the national texts. Indeed, these adaptations remain limited by fear of disadvantaging the students for the national exam. In addition, many context effects are shown, for example linked with local rules (concerning VAT, custom duties...) which are only partially taken into account by teachers. This demonstrates that the French educative system has not yet completely solved the opposition between national guideline and decentralization of the educational action.
19th General Meeting and Biennial Conference “Harnessing Science and Technology to create knowledge-base Economies and preserve Caribbean Ecosystems”
Tobago, Trinidad and Tobago

hal-01535045
https://hal.univ-antilles.fr/hal-01535045

Éditeur(s) : HAL CCSD Oxford University Press (OUP)
Résumé : International audience
Several studies, both theoretical and experimental, show that sedimentary rocks have a fractal pore-grain interface. In this paper a computer simulated 3-D sedimentary rock structure generated by the Relaxed Ballistic Bidisperse Deposition Model (RBBDM), is investigated to characterize the micro structure of its pores. The pore volume and the rock-pore interface show the same fractal dimension indicating that the pore volume is a fractal. The two point density correlation is computed for the pore space and the results compare favourably with the range reported from experiments. An array of 2-D X-ray tomography micrograph sections of a real sedimentary rock, an oolitic limestone (pure calcite) from the Mondeville formation of Middle Jurassic age (Paris Basin, France), was used to generate a 3-D bitmap. The 3-D real rock sample generated in this manner, was analysed for similar studies as the simulated structure. The results were compared with those obtained from simulation. The simulation results agree qualitatively with the real rock sample. Diffusion through the connected pore space of the simulated structure was studied using a random walk algorithm and the results compared with the similar simulation study done on the 3-D oolitic limestone specimen. In both cases diffusion was found to be anomalous indicating that the sedimentary rock has a fractal geometry. The favourable comparability of results between the simulated and real rock supports the usefulness of the model of sedimentary rock generation which can be applicable to transport phenomena.
ISSN: 0956-540X

hal-00823061
https://hal.archives-ouvertes.fr/hal-00823061
DOI : 10.1093/gji/ggs084

Éditeur(s) : HAL CCSD Public Library of Science
Résumé : International audience
DNase I requires Ca²+ and Mg²+ for hydrolyzing double-stranded DNA. However, the number and the location of DNase I ion-binding sites remain unclear, as well as the role of these counter-ions. Using molecular dynamics simulations, we show that bovine pancreatic (bp) DNase I contains four ion-binding pockets. Two of them strongly bind Ca²+ while the other two sites coordinate Mg²+. These theoretical results are strongly supported by revisiting crystallographic structures that contain bpDNase I. One Ca²+ stabilizes the functional DNase I structure. The presence of Mg²+ in close vicinity to the catalytic pocket of bpDNase I reinforces the idea of a cation-assisted hydrolytic mechanism. Importantly, Poisson-Boltzmann-type electrostatic potential calculations demonstrate that the divalent cations collectively control the electrostatic fit between bpDNase I and DNA. These results improve our understanding of the essential role of cations in the biological function of bpDNase I. The high degree of conservation of the amino acids involved in the identified cation-binding sites across DNase I and DNase I-like proteins from various species suggests that our findings generally apply to all DNase I-DNA interactions.
ISSN: 1553-734X

hal-00645165
https://hal.archives-ouvertes.fr/hal-00645165
https://hal.archives-ouvertes.fr/hal-00645165/document
https://hal.archives-ouvertes.fr/hal-00645165/file/journal.pcbi.1001000.pdf
DOI : 10.1371/journal.pcbi.1001000

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) : University of Tasmania, Université de Bretagne Occidentale
Résumé : Empirical evidence and the theoretical literature both point to stock sustainability and the protection of marine biodiversity as important fisheries management issues. Decision-support tools are increasingly required to operationalize the ecosystem-based approach to fisheries management. These tools need to integrate (i) ecological and socio-economic drivers of changes in fisheries and ecosystems; (ii) complex dynamics; (iii) deal with various sources of uncertainty; and (iv) incorporate multiple, rather than single objectives. The stochastic co-viability approach addresses the trade-offs associated with balancing ecological, economic and social objectives throughout time, and takes into account the complexity and uncertainty of the dynamic interactions which characterize exploited ecosystems and biodiversity. This thesis proposes an application of this co-viability approach to the sustainable management of mixed fisheries, using two contrasting case studies: the French Bay of Biscay (BoB) demersal mixed fishery and the Australian Northern Prawn Fishery (NPF). Both fisheries entail direct and indirect impacts on mixed species communities while also generating large economic returns. Their sustainability is therefore a major societal concern. A dynamic bio-economic modelling approach is used to capture the key biological and economic processes governing these fisheries, combining age- (BoB) or size- (NPF) structured models of multiple species with recruitment uncertainty, and multiple fleets (BoB) or fishing strategies (NPF). Economic uncertainties relating to input and output prices are also considered. The bioeconomic models are used to investigate how the fisheries can operate within a set of constraints relating to the preservation of Spawning Stock Biomasses (BoB) or Spawning Stock Size Indices (NPF) of a set of key target species, maintenance of the economic profitability of various fleets (BoB) or the fishery as a whole (NPF), and limitation of fishing impacts on the broader biodiversity (NPF), under a range of alternative scenarios and management strategies. Results suggest that under a status quo strategy both fisheries can be considered as biologically sustainable, while socio-economically (and ecologically in the NPF case) at risk. Despite very different management contexts and objectives, viable management strategies suggest a reduction in the number of vessels in both cases. The BoB simulations allow comparison of the trade-offs associated with different allocations of this decrease across fleets. Notably, co-viability management strategies entail a more equitable allocation of effort reductions compared to strategies aiming at maximizing economic yield. In the NPF, species catch diversification strategies are shown to perform well in controlling the levels of economic risk, by contrast with more specialized fishing strategies. Furthermore analyses emphasize the importance to the fishing industry of balancing global economic performance with inter-annual economic variability. Promising future developments based on this research involve the incorporation of a broader set of objectives including social dimensions, as well as the integration of ecological interactions, to better address the needs of ecosystem-based approaches to the sustainable harvesting of marine biodiversity.
L’objectif général de la thèse est de modéliser les principaux processus biologiques et économiques régissant des pêcheries multi-espèces et multi-flottilles afin de proposer des stratégies viables pour la gestion durable de ces pêcheries mixtes, dans un contexte stochastique et multiobjectif. Plus spécifiquement, cette thèse utilise des analyses de co-viabilité stochastique pour étudier les arbitrages entre des objectifs contradictoires de gestion (conservation, et viabilité économique et sociale) des pêcheries mixtes. Deux pêcheries mixtes sont analysées dans cette thèse: la pêcherie française mixte démersale du golfe de Gascogne et la pêcherie crevettière australienne du Nord (NPF). Ces deux pêcheries sont multi-espèces, et utilisent des stratégies multiples de pêche, induisant des impacts directs et indirects sur les écosystèmes. Cette thèse propose une application de la co-viabilité stochastique à ces deux cas, en prenant en compte leur histoire, leur contexte socio-politique et les différences dans les stratégies et objectifs de gestion. Les résultats suggèrent que le status quo peut être considéré comme une stratégie biologiquement durable mais socio économiquement à risque dans les deux pêcheries (ainsi qu’à risque écologique dans le cas de la pêcherie australienne). Les simulations réalisées pour le golfe de Gascogne permettent de comparer les arbitrages associés à différentes réductions de capacités par flottille et de montrer qu’il existe des solutions de gestion permettant la co-viabilité du système (viabilité biologique des différentes espèces considérées et viabilité socio-économique des flottilles) contrairement à des stratégies de gestion mono-spécifiques ou basées sur la maximisation de la rente. Dans la pêcherie crevettière australienne, l’analyse montre que les stratégies de diversification permettent de limiter le risque économique contrairement aux stratégies plus spécialisées.

Droits : UBO, Univ. Tasmania
http://archimer.ifremer.fr/doc/00206/31731/30134.pdf
http://archimer.ifremer.fr/doc/00206/31731/

Éditeur(s) : Université des Antilles Études caribéennes
Résumé : Dans un monde essentiellement mouvant et dynamique et dont les stratégies de développement sont tout aussi diverses, le monde rural ne reste pas à la traine. Les espaces ruraux qui sont par essence des lieux de survivances culturelles ont de la peine à construire des stratégies de développement par des replis identitaires dans un contexte de mondialisation et marqué particulièrement par une indigence notoire. Dans ce contexte, le tourisme qui demeure une situation de rente pour les ruraux est influencé par de profondes dynamiques exogènes. L’objectif de ce travail est donc d’évaluer le lien social entre les acteurs inscrits dans le développement du tourisme en milieu rural. La problématique est soutenue par les interrogations suivantes : comment résister aux conduites modernes des touristes en milieu rural dans un contexte de mondialisation ? Les modes de vie des touristes en milieu rural sont-ils autant compatibles avec ceux des locaux ? Comment les touristes influencent-ils les modes de vie des acteurs ruraux au point d’en provoquer des innovations socio-économiques ? Le cadre théorique est essentiellement axé sur la théorie du lien social axé sur la finalité de l’échange. La méthode est qualitative, car il est question dans cette étude de ressortir les interactions entre les acteurs en présence dans la problématique du tourisme. Les résultats montrent que : a) le tourisme en milieu rural est une source de rente pour les locaux, b) il y a une innovation dans la gestion des temps traditionnelles, c) les sources de revenus ne sont plus seulement issues de la production agricoles, mais aussi des services, d) les modes de vie des ruraux sont profondément modifiés par les dynamiques portées par les touristes.
In a changing world whose development strategies are diverse, the rural world is not left behind. Rural areas that essentially represent cultural resilience sites are challenged in building development strategies in a globalized world characterized by notorious poverty. In this context tourism, which remains an economic rent for rural, is influenced by exogenous conditions. This paper aims to analyze the social bond between the players enrolled in the development of rural tourism. The analytic process is supported by the following questions: How to resist the modern behaviour of rural tourists in a globalization context? Are the lifestyles of rural tourists compatible with locals? How do tourists influence the lifestyle of rural stakeholders to the point of causing socio-economic innovations? The theoretical framework focuses mainly on the theory of social ties focusing on the purpose of exchange. The method is qualitative, as this study highlights the interactions between the stakeholders. The results show that: a) Rural tourism is a source of income for locals; b) there is an innovation in managing traditional time; c) sources of income are not only from agricultural production but also from services; d) rural lifestyles are profoundly changed by the dynamic brought by tourists.
Cameroun
Kribi

Droits : info:eu-repo/semantics/openAccess
urn:doi:10.4000/etudescaribeennes.8820
http://journals.openedition.org/etudescaribeennes/8820

Éditeur(s) : HAL CCSD American Physical Society
Résumé : International audience
Absolute M-shell x-ray production cross sections have been measured and calculated for Au and Bi for electron incident energies from close to the ionization threshold up to 38 keV. The experimental cross sections were deduced from M alpha x-ray intensities emitted from ultrathin Au and Bi samples deposited on self-supporting C films. The measurements were performed on an electron microprobe using several wavelength-dispersive spectrometers. The x-ray production cross sections were also evaluated theoretically using ionization cross sections calculated from the plane-wave and the distorted-wave Born approximations. Experimental results are compared with the calculated cross sections and also with the results of two analytical formulas widely used in many applications. Good agreement is found between the measured cross sections and the predictions from the distorted-wave Born approximation, which indicates that this approximation is suited for the calculation of M-shell ionization cross sections of heavy elements.
ISSN: 1050-2947

hal-00411432
https://hal.archives-ouvertes.fr/hal-00411432
DOI : 10.1103/PhysRevA.78.022704

Éditeur(s) : EDP Sciences
Résumé : The necessity to move from a traditional fishery management to an ecosystem approach is now acknowledged. Indicators are required to support the development of this approach. For example, community indicators have been proposed to assess the impact of fishing. We tested here the applicability of one such community indicator, the abundance-biomass comparison (ABC method), as a measure of the impact of bottom trawling (years of sampling: 2001 and 2003) on the benthic invertebrates-typically starfishes, crabs, squat lobsters, shrimps and large hard-shelled molluscs-of "Grande Vasiere", a major French fishing zone, in the Bay of Biscay. The ABC method is generally used as an impact indicator for different types of physical, biological and anthropogenic disturbances on benthic communities. This method is based on the assumption that increasing disturbance shifts communities from dominance by large-bodied species with low turnover rates toward dominance by small-bodied species with high turnover rates. At less disturbed areas the average biomass of individuals is greater than at more heavily disturbed areas. The ABC method measures this effect by comparing the ranked distributions of abundance and biomass within a given community. We applied the ABC method and compared the size structure and the species diversity at two areas exposed to moderate and high bottom trawl effort. Species diversity was lower in the most exploited area. The highly trawled area was dominated by opportunistic organisms, mainly one species of swimming crab Liocarcinus depurator, one species of squat lobster Munida rugosa and Norway lobsters Nephrops norvegicus, which are large-bodied species. Consequently, the results of the ABC method were inconsistent with the theoretical expectation for these particular macrofaunal communities and the measured levels of fishing intensity.
La nécessité de passer d'une gestion monospécifique des pêches à une approche écosystémique est largement reconnue. Pour mettre en place une telle approche, des indicateurs ont été proposés afin d'estimer l'impact de la pêche sur les communautés. Nous avons testé l'efficacité de l'un de ces indicateurs, la comparaison abondance-biomasse (méthode ABC), pour mesurer l'impact du chalutage de fond (année d'échantillonnage : 2001 et 2003) sur les communautés de la macrofaune benthique de la Grande Vasière, golfe de Gascogne (typiquement des crabes, étoiles de mer, des galathées, de gros mollusques à coquille dure). La méthode ABC est généralement utilisée comme un indicateur d'impact de différents types de perturbations physiques, biologiques et anthropiques sur les communautés benthiques. Cette méthode est basée sur l'hypothèse qu'un régime de perturbation croissant entraîne une modification de la structure des communautés qui deviennent graduellement dominées par des espèces opportunistes de petite taille caractérisées par un renouvellement rapide. Dans une communauté modérément perturbée, la biomasse moyenne des individus est ainsi plus grande que dans une communauté fortement perturbée. La méthode ABC mesure cet effet en comparant les distributions en biomasse et densité dans chaque communauté. Nous avons appliqué la méthode ABC et étudié la structure en taille et la diversité spécifique des communautés benthiques en comparant deux zones, l'une soumise à un effort de pêche modéré et l'autre à un important effort de pêche. La diversité spécifique était plus faible sur les sites fortement chalutés. Ces sites étaient dominés par des organismes opportunistes de grande taille, principalement une espèce de crabe nageur Liocarcinus depurator, une espèce de galathée Munida rugosa et des langoustines Nephrops norvegicus. Dans ces conditions, les résultats de la méthode ABC n'étaient pas cohérents avec la théorie pour ces communautés de macro-invertébrés benthiques et les efforts de pêche mesurés.
Aquatic Living Resources (0990-7440) (EDP Sciences), 2006-07 , Vol. 19 , N. 3 , P. 219-228

Droits : 2006 EDP
http://archimer.ifremer.fr/doc/2006/publication-2133.pdf
DOI:10.1051/alr:2006022
http://archimer.ifremer.fr/doc/00000/2133/

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
A data stream is a potentially uninterrupted flow of data. Mining this flow makes it necessary to cope with uncertainty, as only a part of the stream can be stored. In this paper, we evaluate a statistical technique which biases the estimation of the support of patterns, so as to maximize either the precision or the recall, as chosen by the user, and limit the degradation of the other criterion. Theoretical results show that the technique is not far from the optimum, from the statistical standpoint. Experiments performed tend to demonstrate its potential, as it remains robust even under significant distribution drifts.
ISSN: 0031-3203

lirmm-00365474
https://hal-lirmm.ccsd.cnrs.fr/lirmm-00365474

Résumé : La notion d’appropriation des langues est définie au regard du contexte guyanais. La Guyane est positionnée au carrefour de la Caraïbe et de l’Amérique du Sud, c’est-à-dire au cœur d’un processus migratoire et de nouvelles problématiques, dont celle du vivre ensemble. Il s’agit de mettre en évidence la réalité dans laquelle s’ancre le locuteur et de présenter les éléments de l’appropriation dans ce contexte plurilingue. L’appropriation de la langue est entendue comme une action – parler – en train de se faire, au cours d’une interaction déterminée sur une échelle espace-temps. La problématique, suivant une approche interactive et interdisciplinaire, repose sur la relation entre les deux volets de ce travail : recherche de terrain et réflexion théorique, laquelle est menée autour des notions d’appropriation, de langue, de sujet et de contexte. La place accordée à l’arrière-plan ethnographique et social, induit une méthodologie basée sur la compréhension des éléments des contextes à décrire, supports des pratiques déclarées par les sujets recueillies par le biais de questionnaires, mais surtout au cours d’entretiens. Deux attitudes sont identifiées, l’une d’ouverture et l’autre de repli sur soi. La première conduit le sujet à s’approprier les langues de son environnement : le sujet développe une identité plurielle, qu’il revendique comme telle, et s’épanouit dans le plurilinguisme, à condition qu’il soit légitimé dans les différentes sphères auxquelles il se réfère. La deuxième consiste à définir la communauté linguistique et culturelle à laquelle le sujet appartient, et dont il réclame l’identité et la légitimité.
The notion of the appropriation of languages is defined under the Guyanese context. French Guyana is placed at the junction of Caribbean and South America, that is at the heart of a migration process and new problems which invites reflection on the « living together ». This is to highligth the reality into which someone is anchored, and to present the components of appropriation in this multilingual context. The appropriation of languages is understood as an action – speak – in the making, during an interaction on a scale determined space-time. The problem, according to an interactive and interdisciplinary approach, is based on the relationship between the two components of this work : the field research and the theoretical thought, which is conducted around the notions of appropriation, language, subject and context. The emphasis on the ethnographic and social background leads consequently to a methodology based on comprehension of the contexts components to describe, supports of linguistic practices declared by subjects collected through questionnaires, but especially during interviews. Two attitudes are identified, one of openness and one of withdrawal. The first leads the subject to appropriate the language of his environment : the subject develops a plural identity, he claims as such, and thrives in multilingualism, provided that he’s legitimized into the spheres he refers to. The second is to define the linguistic and cultural community to which the subject belongs, and that he claims identity and legitimity.

http://www.theses.fr/2011AGUY0466/document