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[en] Keloids are frequent in Martinique; for a population of 360,000, we treat on average 6 keloids per month, and not all are passed on to us. Between 1977 and 1988, 544 patients (of whom 97% were of mixed race), with a total of 855 keloids, were treated by interstitial radiotherapy immediately following total excision. Recurrence rate is 21%, as against 50 to 80% for surgery alone, according to most authors (depending on whether or not surgery was accompanied by a postoperative injection of corticosteroids). This recurrence rate is about the same as for external radiotherapy, but we prefer our method for practical reasons (cost, equipment, radiobiology, technique). 90% of recurrences occurred in the year following therapy, which proves that a follow-up time of at least twelve months is needed for a study of keloids, or even 18 months according to some authors. In our experience, the keloids that are the most likely to recur are the largest and those giving rise to most symptoms. Bruising and loosened stitches, but in particular infection during therapy, largely favour a recurrence, and in any case jeopardize a good cosmetic result. In our series, the symptoms disappeared or were much improved in 80% of cases, and the cosmetic result was judged good by 75% of the patients
Synthesis of knowledge about the geothermal potential of the Morne Rouge - Montagne Pelee and Diamant regions (Martinique) - First works of the BRGM in 2001-2003 - Work progress report. Re-assessment of the geothermal potential in the Morne Rouge - Montagne Pelee and Diamant regions (Martinique): geological study + geochemical study + geophysical study - Appendices + main conclusions and recommendations
[en] A first report proposes syntheses of geological (recent tectonic stresses, geological presentation or characterisation, zones of geothermal interest), geochemical (geochemistry of thermal waters, mercury explorations, gas explorations) and geophysical (geophysical methods of exploration, analysis of existing data) knowledge for regions of the Martinique island (Morne Rouge - Montagne Pelee and Diamant), and a description of the first works performed by the BRGM in 2001-2003 (structural geology reconnaissance campaign, sampling and analysis of thermal source waters. The second document reports a new occurrence of the same study, and comprises descriptions of the geology of both studied regions, a geochemical study (sampling, chemical and isotopic analyses, result interpretation, and gas measurements in soils), a geophysical study (methods, geomagnetic and gravimetric measurements, results interpretation for both regions, appendices with measurements and results). A last report proposes a synthesis of previous works, and states some conclusions and recommendations
[en] Chlordecone is a toxic organochlorine insecticide that was used in banana plantations until 1993 in the French West Indies. This study aimed at assessing the potential of near infrared reflectance spectroscopy (NIRS) for determining chlordecone content in Andosols, Nitisols and Ferralsols from Martinique. Using partial least square regression, chlordecone content conventionally determined through gas chromatography-mass spectrometry could be correctly predicted by NIRS (Q2 = 0.75, R2 = 0.82 for the total set), especially for samples with chlordecone content <12 mg kg-1 or when the sample set was rather homogeneous (Q2 = 0.91, R2 = 0.82 for the Andosols). Conventional measures and NIRS predictions were poorly correlated for chlordecone content >12 mg kg-1, nevertheless ca. 80% samples were correctly predicted when the set was divided into three or four classes of chlordecone content. Thus NIRS could be considered a time- and cost-effective method for characterising soil contamination by chlordecone. - Soil content in chlordecone, an organochlorine insecticide, can be determined time- and cost-effectively using near infrared reflectance spectroscopy (NIRS).
[en] Ocean thermal energy conversion (OTEC) is a form of power generation, which exploits the temperature difference between warm surface seawater and cold deep seawater. Suitable conditions for OTEC occur in deep warm seas, especially the Caribbean, the Red Sea and parts of the Indo-Pacific Ocean. The continuous power provided by this renewable power source makes a useful contribution to a renewable energy mix because of the intermittence of the other major renewable power sources, i.e. solar or wind power. Industrial-scale OTEC power plants have simply not been built. However, recent innovations and greater political awareness of power transition to renewable energy sources have strengthened the support for such power plants and, after preliminary studies in the Reunion Island (Indian Ocean), the Martinique Island (West Indies) has been selected for the development of the first full-size OTEC power plant in the world, to be a showcase for testing and demonstration. An OTEC plant, even if the energy produced is cheap, calls for high initial capital investment. However, this technology is of interest mainly in tropical areas where funding is limited. The cost of innovations to create an operational OTEC plant has to be amortized, and this technology remains expensive. This paper will discuss the heuristic, technical and socio-economic limits and consequences of deploying an OTEC plant in Martinique to highlight respectively the impact of the OTEC plant on the environment the impact of the environment on the OTEC plant. After defining OTEC, we will describe the different constraints relating to the setting up of the first operational-scale plant worldwide. This includes the investigations performed (reporting declassified data), the political context and the local acceptance of the project. We will then provide an overview of the processes involved in the OTEC plant and discuss the feasibility of future OTEC installations. We will also list the extensive marine investigations required prior to installation and the dangers of setting up OTEC plants in inappropriate locations.
[en] Sea level rise accelerated by climate change is of major concern at international scale since the 1990's. From now on, climate change adaptation is institutionalized from global to local scales. I analyze policy making processes related to climate change adaptation in French coastal areas. Two qualitative case studies are at the heart of the thesis: Aquitaine coastline and Martinique Island (French West Indies). They are contrasted in their history, their coastal planning policy and their social dynamics, though they share common processes of attractiveness and vulnerability to submersion and coastal erosion. I analyze discourses, actors and policy instruments in the legitimization of anticipation and preparation as guiding principles to cope with coastal risks and threats. The theoretical framework builds on political sociology of science and policy, as well as insights from pragmatic sociology. Direct observation of local, regional and national consultation and steering committees, semi-structured interviews and documentation analysis are the key methodological approaches. A questionnaire survey has been conducted in the coastal town of Lacanau, on Aquitaine coastline, in order to analyze the way in which residents and users experiment coastal retreat. The main line of argumentation advanced in this thesis is that coastal adaptation to climate change proceeds with performative governance, by which policy devices and narratives are geared towards building adaptation policies upon their interpretive effects. I demonstrate how climate adaptation mainstreaming and planning (adaptation and coastal risks prevention plans...) is combined with experimentalist forms to govern new adaptation options (like planned retreat) and with a new public risk management in which political and institutional risks are as important to prevent as socio-ecological vulnerabilities. The concept of 'public action strategy' is built to better capture these forms of managerial policy instruments used for framing, rationalizing and performing a governance of preparedness and adaptation, by means of expert knowledge, collaborative procedures and dialogue to render local actors accountable for their own security. State steering practices and decentralization policies are key processes shaping coastal adaptation and risk regulation. This new public risk management strengthens expert configurations for defining and operationalizing coastal risks policy strategies. (author)
[fr]L'elevation des niveaux marins acceleree par le changement climatique fait l'objet d'une attention soutenue au niveau international depuis les annees 1990. L'adaptation des littoraux au changement climatique est desormais en voie d'institutionnalisation de l'echelle internationale jusqu'au niveau local. La these analyse les processus de mise en politique de l'adaptation au changement climatique sur les littoraux francais, a partir de deux cas d'etude contrastes dans leur histoire, leurs politiques d'amenagement et leurs configurations sociales, mais traverses par des processus analogues d'attractivite et de vulnerabilite face aux submersions marines et a l'erosion cotiere: la cote aquitaine et le littoral martiniquais. La these soutient que la mise en politique de l'adaptation au changement climatique en zones cotieres procede d'une gouvernance performative, definie comme un ensemble de dispositifs et d'enonces visant a faire advenir des mesures d'adaptation en les mettant a l'epreuve du reel. La these propose de montrer qu'entre une planification par integration du changement climatique dans les politiques littorales existantes (plan national d'adaptation, plans de prevention des risques littoraux...), et des formes d'experimentation de nouvelles options d'adaptation (relocalisation des biens et des activites ou repli strategique), emerge une 'nouvelle gestion publique des risques' littoraux. Pour cette derniere, le concept de strategie d'action publique rend compte de ces formes d'instrumentation qui visent a encadrer, a rationaliser et a faire emerger de nouveaux referentiels gestionnaires (comme l'adaptation et la preparation) par de l'expertise scientifique et technique, par des procedures collaboratives et de la concertation citoyenne en vue d'une responsabilisation individuelle et collective des acteurs locaux. L'analyse des discours, des logiques d'acteurs et des instruments visant a legitimer une action publique guidee par l'anticipation et la preparation face aux risques et aux menaces, mobilise la sociologie de l'action publique, la sociologie des sciences et de l'expertise, et la sociologie pragmatique des problemes publics. Des enquetes par observation directe de situations de negociation et de concertation, par entretiens et par analyse de documents d'expertise et de planification ont Ete menees sur chaque terrain d'etude; une enquete par questionnaire a Ete conduite sur la commune de Lacanau afin d'apprehender l'experience des citoyens-usagersriverains face a l'evolution et au recul du trait de cote. (auteur)
[en] France disposes of several very low-temperature to very high-temperature geothermal resources located at different depths, geographical locations and geological settings. The very low-temperature geothermal resources (below 30 deg. C) are located in shallow layers and aquifers and are exploited with ground source heat pump or ground water heat pumps. These resources are scattered all over the territory but they represent a too low energy potential for the development of electricity production. They are not described in this report. The low-energy resources (between 65 deg. C and 90 deg. C) are located in aquifers contained in the major sedimentary basins, i.e. the Paris Basin, the Aquitaine Basin, the Upper Rhine Graben, the Limagne and Bresse region, the Rhone corridor and the Mediterranean region but also in faulted or folded regions. The geothermal resources with temperatures between 90 deg. C and 150 deg. C are in the course of evaluation. A very recent study, performed by BRGM and co-financed by ADEME, named CLASTIQ (Clayey sandstone In Question) explore new or poorly well-known deep silico-clastic geothermal reservoirs (Triassic reservoirs in Alsace and Paris Basin, Tertiary reservoirs in Limagne) with fluids temperatures around 80 deg. C and 120 deg. C. The resources higher than 150 deg. C. are located in the Overseas Departments (the volcanic islands of the Antilles - Guadeloupe and Martinique - and the Indian Ocean - Reunion) and in the crystalline basement where injection of water in fractures and production of heated fluid leads to the concept of EGS (Soultz-sous-Foret scientific pilot plant). This document focuses on the deep geothermal resources with temperatures between [65 deg. C-90 deg. C] and [90 deg. C-150 deg. C] in the different regions in France and presents the available information about the thickness and the temperature of this potential geothermal reservoirs. The temperatures are those present at depth, they are different from the temperatures that will be encounter at surface. The difference between the bottom hole temperature and the wellhead temperature depends on the depth of the resource and the flow rate at which the fluid is extracted
[en] Since 1972, the French departments of Guadeloupe and Martinique have intensively used organochlorinated pesticides such as chlordecone (CLD) and hexachlorocyclohexane (HCH) isomers to prevent the proliferation of banana weevil (Cosmopolite sordidus). These molecules are stable in the environment, leading to a continuous contamination of soils, water, and food chain in the banana-producing areas. In these polluted areas, water treatment plants are equipped with activated carbon (AC) filters. In order to improve treatment of CLD-contaminated waters by AC, CLD adsorption and desorption kinetic studies are carried out using different ACs produced from sugar cane bagasse as adsorbents and subsequent CLD degradation is performed using reduced vitamin B12 (VB12). A GC-MS method for CLD quantification is as well optimized. This study shows that bagasse ACs are able to capture the pollutant, leading to a CLD concentration decrease from 1 to 73 μg L−1, with an adsorption capacity of 162 μg mg−1. Adsorption capacity increase with the temperature indicates an endothermic process. Polar solvents favor CLD desorption from ACs, suggesting hydrogen bonding between CLD and surface groups of ACs, the best solvent for chemical desorption being ethanol. Subsequent degradation of CLD in ethanol is performed using vitamin B12 reduced by either 1,4-dithiotreitol (DTT) or zerovalent zinc, leading to 90% of CLD removal and to the molecule cage structure opening for formation of a pentachloroindene intermediate product, characterized by GC MS/MS. A pathway for pentachloroindene formation from CLD is proposed.