Dissertations / Theses on the topic 'Guide de prospection'

L’existence de fluides géologiques riches en hydrogène (H2) doit nécessairement faire l’objet de travaux d’exploration afin de statuer sur le potentiel énergétique de cette éventuelle ressource décarbonée. Depuis plus d’un siècle de nombreuses exhalations naturelles d’H2 ont été mis en évidence. Or à ce jour il n’existe aucun guide d’exploration basé sur une méthodologie et sur des indicateurs robustes. La détection d’occurrence gazeuse en surface correspond bien évidemment à l’approche la plus efficace et la plus rapide à mettre en œuvre pour identifier des flux. Il n’en reste pas moins qu’un flux ne constitue pas une ressource pour autant, puisqu’à ce jour, l’homme n’exploite que les stocks de ressources énergétiques fossiles. Il sera donc important de développer un guide d’exploration non pas orienté uniquement sur une problématique de surface, mais aussi sur des considérations géologiques profondes intégrant le système hydrogène dans son entier de la source au piège ou à la fuite dans l’atmosphère.Au cours de ce travail de thèse nous proposons d’utiliser le cadre géologique du piémont nord Pyrénéen pour élaborer un guide d’exploration. La compilation des données bibliographiques a révélé un contexte prometteur pour un système H2 du fait d’un lien entre sources profondes, chemins de migration crustale, dynamique de circulation de fluides, et pièges sédimentaires. En effet le nord-ouest des Pyrénées et plus particulièrement le Bassin Mauléon est caractérisé par la présence i) d’un corps mantellique (<10 km) où les conditions pression-température sont favorables à la serpentinisation ; ii) d’accidents structuraux majeurs tels que le Chevauchement Frontal Nord Pyrénéens (CFNP) constituant des drains collecteurs de grande ampleur, iii) des gradients hydrauliques, conjugués à des gradients de température et de pressions qui permettent la mise en mouvement des fluides ; iv) des formations sédimentaires imperméables ou de couvertures comme les évaporites ou les argiles consitutant des pièges pour accumuler l’H2.Suite à cette étude préalable, nous avons mis en place une campagne d’analyses des gaz du sol (H2, CO2, 222Rn, O2, CH4) à l’échelle régionales. Cette campagne d’analyse réalisée sur plus de 7500 km2 a très vite permis de mettre en évidence une zone à très fortes anomalies en H2, CO2, et 222Rn sur le pourtour du Bassin de Mauléon. Cette découverte nous a permis de resserrer rapidement le maillage de prospection sur la partie nord du bassin de Mauléon. Une campagne d’analyses géochimiques et géophysiques a été réalisée à Sauveterre-de-Béarn afin de déterminer l’origine et le parcours des gaz à l’origine de cette anomalie. Sur la base de l'analyse des gaz du sol et des levés électromagnétiques, nous avons confirmé l'existence d'une faille drainant les fluides profonds. De plus, l’étude des données historiques des forages entrepris dans la région il y a plus de 50 ans, conjugué à une mise en perspective des dernières connaissances géologiques et géophysiques de la région, nous a permis de mettre en évidence des zones où l’H2 pourrait s’accumuler.Enfin une partie expérimentale de broyage de quartz et de roches de la région a été menée afin d’explorer de nouveaux mécanismes de production d’H2 le long des failles. Nous avons mis en évidence une très forte influence du rapport eau/roche (W/R) et du pH sur la production d’H2. Ces découvertes apportent un éclairage nouveau sur les mécanismes mécano-radicalaires de production d’H2 où la spéciation des sites des surface des minéraux sont des paramètres clés contrôlant la production d’H2. Nous révélons pour la première fois que le broyage du quartz en présence de solutions carbonatés induit la formation d’espèces carboxylates (formate, acétate, oxalate). En plus de produire de l’H2, les mécanismes mécano-radicalaires permettent donc de produire des espèces réduites du carbones pouvant constituer une source d’énergie pour les écosystèmes microbiens lithotrophe de subsurface
The existence of geological fluids rich in hydrogen (H2) rise the question about the energy potential of this carbon-free resource. For more than a century and throughout the world, numerous natural H2 seepages have been discovered. However, to date there is no exploration approach based on robust methodologies and pathfinders. The detection of H2 seepages at the surface is known to be the most ecient and straight forward approach to identify H2 flows. However, a gas flow does not necessarily constitute a resource, since to date, mankind only exploit reservoirs of fossil energy resources. Therefore, it is important to develop an exploration guide that is not only focusing on surface gas monitoring, but also considering a deep geological approach integrating the entire hydrogen system from source to trap or leakage into the atmosphere. Here, we propose to use the geological framework of the North Pyrenean foothills as a case study to develop this exploration guide. A literature review of the area revealed a promising geological setting for a H2 system due to a strong link between putative deep H2 sources, crustal-scale migration pathways, fluid circulation dynamics, and sedimentary traps. Indeed, the northwestern Pyrenees and particularly the Maul´eon Basin is characterised by the presence of i) an ultramafic mantle body located less than 10 km depth and under pressure-temperature conditions favourable to serpentinisation ; ii) major faults such as the North Pyrenean Frontal Thrust (NPFT) constituting large-scale flow convergence and drainage, iii) hydraulic gradients due to the presence of strong reliefs, combined with temperature and pressure gradients that trigger fluids ; iv) impermeable sedimentary formations or caprocks such as evaporites or claystones overlying porous reservoir rocks that can constitute traps for accumulating H2.Following this preliminary geological survey, we set up a soil gas exploration campaign (H2, CO2, 222Rn, O2, CH4) at the regional scale. These field measurments, carried out over more than 7,500 km2, revealed several hotspots with very high H2, CO2 and 222Rn concentrations anomalies around the Maul´eon Basin. This discovery allowed us to refine the mesh of the prospecting grid to the northern part of the Maul´eon Basin around the locality of Sauveterre-de-Béarn. Geochemical and geophysical measurements were carried out at Sauveterre-de-B´earn to determine the source and migration path of the gases at the origin of this anomaly. Based on soil gas analysis and electromagnetic surveys, we confirmed the existence of a fault draining deep fluids. In addition, the study of historical data from drilling carried out in the region more than fifty years ago, combined with the latest geological and geophysical knowledge of the region, enabled us to highlight zones where H2 could accumulate.Finally, an experimental part of comminution of quartz and rocks from the region was carried out in order to explore the reaction mechanisms of H2 production in active fault zones. We reveal the very strong influence of the water/rock ratio (W/R) and pH on H2 production. These findings shed new light on the mechano-radical mechanisms of H2 production where the efficiency of grinding as well as the speciation of mineral surface sites are key parameters controlling H2 production. We reveal for the first time that grinding of quartz in the presence of carbonate solutions induces the formation of carboxylate species (formate, acetate, oxalate). In addition to producing H2, the mechano-radical mechanisms thus allow the production of reduced carbon species that can constitute an energy source for subsurface lithotrophic microbial ecosystems

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Conselho Nacional de Desenvolvimento Científico e Tecnológico
A região de Itutinga foi alvo de estudos prospectivos por parte da empresa BP mineração na década de 80, onde foram encontradas mineralizações em lentes de sulfetos metálicos (Zn-Cu-Ag-Fe) associados a rochas komatiíticas peridotíticas e basaltos toleíticos (anfibolitos) do greenstone belts, nas proximidades da fazenda São Jerônimo, enquadrando-se em um depósito do tipo VMS. A partir destas informações encontradas na literatura propôs-se estudar a estaurolita, a magnetita e a ilmenita para, a partir da determinação do seu conteúdo em zinco, indicar a aplicabilidade destes três minerais como traçadores desses tipos de depósitos. Para isso foram coletadas amostras de sedimentos de corrente e concentrados de batéia na região próxima à ocorrência, no entorno da cidade de Itutinga, e também em uma região próxima a cidade de Itumirim, já que existem semelhanças litológicas entre as duas áreas. Os sedimentos de corrente, as frações magnéticas e as frações de 0,3A (separador eletromagnético Frantz) foram enviados para análises químicas por absorção atômica e ICP-OES. Os concentrados de batéia foram descritos, separando-se cristais de estaurolita de cada amostra coletada, e analisando-os em MEV-EDS para determinação da química mineral. Os resultados dos sedimentos de corrente apontaram que os pontos da fazenda São Jerônimo (ME-03, Itutinga 51,7 ppm de Zn) e o ponto do Ribeirão Santa Cruz, (ME-06, Itumirim 36,1 ppm de Zn) foram os que apresentaram melhores resultados, indicando anomalias em zinco nas duas áreas estudadas . As estaurolitas, retiradas dos concentrados de batéia de cada ponto estudado, foram divididas em três conjuntos, de acordo com os teores de ZnO encontrados: 1 - entre 2,96% e 3,25% de ZnO em peso; 2 - entre 2,03% e 2,76% de ZnO em peso; 3 - < 1,67% de ZnO em peso, sendo comparável com outras estaurolitas encontradas em diversos depósitos de Zn do mundo, como Dry River, Austrália e Palmeirópolis Goiás. Assim, as estaurolitas apresentam bons resultados como minerais indicadores na área estudada. Em relação as magnetitas e ilmenitas estudadas, o número de amostras coletadas no presente estudo foram muito pequenas para se ter informações conclusivas sobre o papel destes minerais como traçadores. Por outro lado, os resultados das análises químicas nos concentrados de ilmenita (até 856 ppm de Zn) e nos concentrados de magnetita (até 216 ppm de Zn), indicam a disponibilidade deste metal nas áreas estudadas. Assim, é possível se detectar a presença do zinco por dois meios: através de sedimentos de corrente, através de halos de dispersão química do elemento zinco, e através dos minerais resistatos (estaurolita zincífera, magnetita e ilmenita), a partir de uma dispersão clástica do grão.
The Itutinga region was studied for BP mineration in 80s , where they found sulphide mineralization in lenses (Zn-Cu-Ag-Fe) associated with komatiitic peridotite rocks and tholeitic basalts (amphibolites) of greenstone belts, near of Fazenda São Jerônimo. With this information in the literature the propose is study the staurolite, magnetite and ilmenite for indicating the applicability of these three minerals as tracers of these types of mineralization. For this, samples of stream sediment and panning concentrates in the region near the city of Itutinga, and also in a region near the city of Itumirim. The stream current, magnetic fractions and ilmenite fractions were sent to chemistry analyses (Atomic absorption and ICP-OES), and the panning concentrates were analyzed for the separating of staurolite crystals, and sent to SEM-EDS. The stream sediments results showed that the point of Fazenda São Jerônimo (ME-03, Itutinga 51,7 ppm of Zn) and the point of Ribeirão Santa Cruz (ME-06, Itumirim 36,1 ppm of Zn) were presented the best result. The staurolite of panning concentrates were divided into three groups according to levels of ZnO matched: 1 - between 2.96% and 3.25% by weight of ZnO, 2 - from 2, 03% and 2.76% by weight of ZnO, 3 - <1.67% ZnO by weight, comparable with other staurolite found in many zinc deposits in the world, such as Dry River, Australia and Palmeirópolis Goiás. Thus, the staurolite show good results as indicator minerals in the area. With respect to magnetite and ilmenite concentrates, the number of samples collected in both areas was too small to have conclusive information. On the other hand, the results of the chemical ilmenite (up to 856 ppm Zn) and magnetite (up to 216 ppm Zn), indicate the availability of this metal in the areas studied. Thus, it is possible to detect the presence of zinc by two means: through stream sediments through chemical dispersion halos of zinc, minerals and through resistive minerals (zincian staurolite, magnetite and ilmenite), from a crystal clastic dispersion.

Étude pétrographique et géochimique des ultrabasites serpentinisées des chromites associées et du volcanisme basique d'el-aoujda. L'ensemble constitue l'ossature d'un cortège ophiolitique dont la disposition est inversée par le biais d'une technique chevauchante. L'étude réalisée sur la partie volcanique révèle une nature de tholéites océaniques avec un aspect calco-alcalin par endroits, ajoutée d'une lignée alcaline. Ce complexe recéle des minéralisations métalligènes (CR, NI, CO, CU, ETC. . . ) dont certaines ont valeur d'indices. On tire certaines conclusions sous forme de guides de prospection

The United States Naval Facilities Engineering Command awarded over 1-billion dollars in construction contracts in 1990 and is expected to increase that figure in 1991. These contracts will be awarded all over the world. They will range in size from five thousand dollar playgrounds to hundred million dollar buildings. The objective of this paper is to develop a guide that will allow contractors to make a smooth transition from contracting with other sources into contracting with the United States Navy. It will cover various areas that often lead to difficulties for contractors unfamiliar with Navy construction contracting. Also the guide will provide an overview of the entire contracting experience from reading the advertisement for the job, to the warranty period after construction. It should be understood that the information presented in this guide applies to the most common type of construction contract used by the Navy - fixed price/lump sum.

Lévolution des modes de vie conduit à une évolution des besoins et des souhaits des personnes, en quête «d'expérience », de « bien-être » et de « plaisir » à travers les produits qu'elles utilisent. Les entreprises doiventaujourd'hui satisfaire et séduire ces personnes de plus en plus exigeantes, en étant source d'innovation et denouveauté. Ainsi, elles s'intéressent de plus en plus dans leur démarche de conception de produits à une meilleureprise en compte du facteur humain. Faire vivre aux personnes des expériences positives et de qualité, demandeune démarche spécifique qui les placent au centre des préoccupations des acteurs-métier de la conception deproduits. Dans ce contexte, le processus de conception requiert l'intervention de différentes disciplines sensiblesjustement au facteur humain. Ainsi dans le cadre de nos travaux de recherche, nous nous sommes intéressés aurapprochement de l'ergonomie et du design, deux disciplines sensibles aux personnes qui évoluent vers denouvelles pratiques : le design pour « des besoins » et l'ergonomie prospective. Nous axons nos travaux derecherche sur les pratiques de ces deux disciplines qui convergent vers une vision commune, prospective et «humaniste » de la conception de produits, pour une meilleure prise en compte des personnes. Le principal enjeuscientifique de notre travail est de mieux cerner les pratiques actuelles, de l'ergonomie et du design dans uncontexte de conception de produits. Ceci, pour proposer à ces acteurs-métier une démarche (IDLifeS) et des outils(Guides de Connaissances), interdisciplinaires, qui correspondent à l'évolution de leurs pratiques respectives et quileur permettent de co-concevoir des produits et des situations de vie qui correspondent aux besoins, aux souhaits etaux caractéristiques des personnes
Lifestyles change led to the development of the needs and wishes of people who are looking for "experience", "wellbeing"and "pleasure" through the products they use. Companies must now satisfy and seduce these people whoare increasingly exigent, by being a source of innovation and new ideas. Thus, companies are more and moreinterested in their product design process, in order to better take into account, the human factor. It requires aspecific approach to make people have positive and quality experiences. In this approach, people are at the heart ofthe concerns of the product design actors. In this context, the design process requires the intervention of differentdisciplines rightly sensitive to human factor. In our research, we focused on ergonomics and design, two disciplinessensitive to people who are moving towards new practices: design for "needs" and the prospective ergonomics. Ourresearch is focus on the practices of these two disciplines that converge on a common vision, which is a prospectiveand "humanist" one, of the product design for a better integration of people. The main scientific challenge of ourwork is to better understand ergonomics and design current practices in a product design context. This, to suggestto these actors an approach (IDLifeS) and tools (Knowledge Guides), interdisciplinary, which correspond to thedevelopment of their practices and offer them to co-design products and life situations which correspond to theneeds, wishes and characteristics of people

Aims: The aim of this study was to compare two different methods of root surface debridement for the treatment of moderate to advanced chronic periodontitis; fluorescence-guided laser debridement using an Er:YAG laser (ERL) or mechanical scaling and root-planing (SRP/UL) using an ultrasonic scaler and hand instruments. The effectiveness of each treatment method was assessed by patient-centred outcomes such as clinical periodontal measurements and patients� overall experience. Methods: This study was a phase IV randomised controlled clinical trial, with all examinations and treatments carried out between 1st February 2007 and 7th March 2008. Using a split-mouth design, each patient received both test and control treatments. The control quadrants received scaling and root planing using a Piezon� (EMS, Nyon, Switzerland) ultrasonic scaler and Gracey curettes, while the test quadrants received fluorescence-guided Er:YAG laser root debridement (Keylaser 3, Kavo, Biberach, Germany; panel settings 160mJ/pulse, 10Hz, water spray, 655nm fluorescence calculus-detection system). Full mouth clinical measurements [plaque index (PlI), probing depth (PD), gingival recession (GR), bleeding on probing (BOP), and clinical attachment level (CAL)] were recorded at baseline, and 6 and 12 weeks post-therapy. A patient questionnaire was used to evaluate patient perception in terms of pain, discomfort and satisfaction during treatment, and 24 hours and one week post-treatment. A wash-out period of 6 weeks enabled each patient to evaluate their experience of each treatment on its own merit. Results: Twenty-eight patients received both treatments and completed the patient perception questionnaire. No significant difference was found between ERL and SRP/UL in terms of pain and discomfort during treatment, and 24 hours and one week post-treatment. In terms of patient satisfaction, none of the patients rated ERL more favourably than SRP/UL immediately following treatment, however no significant difference was found 24 hours later and one week post-therapy. Complete clinical data was collected for 22 patients, four of whom increased their tobacco consumption to [greater than or equal to] 10 cigarettes/day. Therefore, the analysis of clinical data was carried out twice with respect to patients� smoking status. In patients who smoked [less than or equal to] 9 cigarettes/day (n = 18 patients), ERL provided less PD reduction at 6 and 12 weeks (p < 0.001, 6 weeks; p < 0.05, 12 weeks) than SRP/UL. Even though SRP/UL quadrants had a greater proportion of sites with BOP (% BOP) at baseline, at 6 weeks they showed a significantly greater reduction in %BOP (p = 0.0123) than ERL quadrants, however there was with no significant difference in bleeding scores (p = 0.202) at 12 weeks post-therapy. When patients who smoked [greater than or equal to] 10 cigarettes/day were included in the analyses (n = 22 patients), ERL resulted in less BOP reduction and PD reduction at 6 and 12 weeks following treatment (BOP reduction: 6 weeks p < 0.05, 12 weeks p < 0.001; PD reduction: 6 weeks p < 0.01, 12 weeks p < 0.05). Although statistically significant, the differences between the treatment groups were very small and were not clinically significant. Conclusion: The use of ERL for root surface debridement offers no significant advantages over mechanical therapy in the treatment of moderate to advanced chronic periodontitis, in terms of clinical outcomes and patient perception of pain, discomfort or satisfaction related to the procedure.

Avec l’avènement du traitement distribué et l’utilisation accrue des services web inter et intra organisationnels alimentée par la disponibilité des connexions réseaux à faibles coûts, les données multisources partagées ont de plus en plus envahi les systèmes d’informations. Ceci a induit, dans un premier temps, le changement de leurs architectures du centralisé au distribué en passant par le coopératif et le fédéré ; et dans un deuxième temps, une panoplie de problèmes d’exploitation allant du traitement des incohérences des données doubles à la synchronisation des données distribuées. C’est le cas des bases de prospection marketing où les données sont enrichies par des fichiers provenant de différents fournisseurs.Nous nous intéressons au cadre particulier de construction de fichiers de prospection pour la réalisation de campagnes marketing B-to-B, tâche traitée manuellement par les experts métier. Nous visons alors à modéliser le raisonnement de brokers humains, afin d’optimiser et d’automatiser la sélection du « plan fichier » à partir d’un ensemble de données d’enrichissement multisources. L’optimisation en question s’exprimera en termes de gain (coût, qualité) des données sélectionnées, le coût se limitant à l’unique considération du prix d’utilisation de ces données.Ce mémoire présente une triple contribution quant à la gestion des bases de données multisources. La première contribution concerne l’évaluation rigoureuse de la qualité des données multisources. La deuxième contribution porte sur la modélisation et l’agrégation préférentielle des critères d’évaluation qualité par l’intégrale de Choquet. La troisième contribution concerne BrokerACO, un prototype d’automatisation et d’optimisation du brokering multisources basé sur l’algorithme heuristique d’optimisation par les colonies de fourmis (ACO) et dont la Pareto-optimalité de la solution est assurée par l’utilisation de la fonction d’agrégation des préférences des utilisateurs définie dans la deuxième contribution. L’efficacité du prototype est montrée par l’analyse de campagnes marketing tests effectuées sur des données réelles de prospection
In Business-to-Business (B-to-B) marketing campaigns, manufacturing “the highest volume of sales at the lowest cost” and achieving the best return on investment (ROI) score is a significant challenge. ROI performance depends on a set of subjective and objective factors such as dialogue strategy, invested budget, marketing technology and organisation, and above all data and, particularly, data quality. However, data issues in marketing databases are overwhelming, leading to insufficient target knowledge that handicaps B-to-B salespersons when interacting with prospects. B-to-B prospection data is indeed mainly structured through a set of independent, heterogeneous, separate and sometimes overlapping files that form a messy multisource prospect selection environment. Data quality thus appears as a crucial issue when dealing with prospection databases. Moreover, beyond data quality, the ROI metric mainly depends on campaigns costs. Given the vagueness of (direct and indirect) cost definition, we limit our focus to price considerations.Price and quality thus define the fundamental constraints data marketers consider when designing a marketing campaign file, as they typically look for the "best-qualified selection at the lowest price". However, this goal is not always reachable and compromises often have to be defined. Compromise must first be modelled and formalized, and then deployed for multisource selection issues. In this thesis, we propose a preference-driven selection approach for multisource environments that aims at: 1) modelling and quantifying decision makers’ preferences, and 2) defining and optimizing a selection routine based on these preferences. Concretely, we first deal with the data marketer’s quality preference modelling by appraising multisource data using robust evaluation criteria (quality dimensions) that are rigorously summarized into a global quality score. Based on this global quality score and data price, we exploit in a second step a preference-based selection algorithm to return "the best qualified records bearing the lowest possible price". An optimisation algorithm, BrokerACO, is finally run to generate the best selection result

The purpose of this prospective, randomized, controlled clinical investigation is to evaluate the performance of the Motorized Ridge Expanders (MRE), and to compare its results with the ones achieved utilizing lateral ridge augmentation (LRA). Eight subjects with bilateral ridge deformities were selected. One technique was used on the right site and the other on the left site. Implants were placed six months after the bone augmentation procedures. All the measurements were recorded at 2 and 5 mm from the most coronal part of the crest. The augmentation achieved with both techniques was statistically significant, 1.2 mm in the LRA, 1.5 mm in MRE at 2 mm from the crest; 1.5 mm and 1.6 mm respectively at 5mm from the crest. The differences between the two techniques were statistically insignificant. The amount of expansion achieved in the MRE site appears to be negatively correlated (P-Value <0.05) with the thickness of the cancellous bone, and it is not affected by the thickness of the cortical plate. The MRE technique appears to be as effective as the LRA technique in augmenting the thickness of atrophic ridges. The defect treated with the MRE showed less bone width contraction during the first 6 months of healing. Histologically, the regenerated bone was vital, trabecular in nature and in direct contact with bone graft particles.
El propósito de esta investigación clínica prospectiva y aleatoria es comparar el aumento horizontal de la cresta alveolar obtenido con el uso de los expansores motorizados de cresta (EMC) y con regeneración ósea guiada (ROG). Fueron selecccionados ocho pacientes con deformidades horizontales del reborde alveolar bilaterales que iban a recibir implantes dentales. Una técnica de regeneración se utilizó en el lado derecho y la otra en el lado izquierdo, para un total de 23 muestras, 13 en el lado experimental (EMC) y 10 en el lado control (ROG). Los implantes fueron colocados seis meses después de los procedimientos de aumento óseo, y se obtuvo una muestra de hueso para estudio histológico. Todas las mediciones clínicas se registraron a los 2 y 5 mm de la parte más coronal de la cresta. El aumento logrado con ambas técnicas fue estadísticamente significativo, de 1,2 mm en la ROG y 1,5 mm con los EMC a 2 mm de la cresta; y 1,5 mm y 1,6 mm, respectivamente, a 5mm de la cresta. Las diferencias entre las dos técnicas no fueron estadísticamente significativas. La cantidad de expansión lograda en el sitio de los EMC parece tener una correlación negativa (p <0,05) con el grosor del hueso esponjoso, y no se ve afectada por el grosor de la cortical. Histológicamente se observó osteoconductividad del injerto óseo y más partículas residuales del mismo en el lado experimental. La técnica de los EMC parece ser tan eficaz como la técnica de ROG en el aumento de la anchura de las crestas atróficas. Los defectos tratados con los EMC mostraron una menor contracción del injerto óseo durante los 6 meses de cicatrización.
El propòsit d'aquesta recerca clínica prospectiva i aleatòria és comparar l'augment horitzontal de la cresta alveolar obtingut amb l'ús dels expansors motoritzats de cresta (EMC) i amb regeneració òssia
guiada (ROG). Es van selecccionar vuit pacients amb deformitats horitzontals bilaterals de la cresta alveolar on es col.locaren implants dentals. Una tècnica de regeneració es va emprar en el costat dret i l'altra a la banda esquerra, per a un total de 23 mostres, 13 al costat experimental (EMC) i 10 en el costat control (ROG). Els implants van ser col.locats sis mesos després dels procediments d'augment ossi, i es va obtenir una mostra d'os per estudi histològic.Totes les mesures clíniques es van registrar als 2 i 5 mm de la part més coronal de la cresta. L'augment aconseguit amb ambdues tècniques va ser estadísticament significatiu, de 1,2 mm a la ROG i 1,5 mm amb els EMC a 2 mm de la carena, i 1,5 mm i 1,6 mm, respectivament, a 5mm de la cresta. Les diferències entre les dues
tècniques no van ser estadísticament significatives. La quantitat d'expansió aconseguida en el lloc dels EMC sembla tenir una correlació negativa (p<0,05) amb el gruix de l'os esponjós, i no es veu afectada per el gruix de la cortical. Histològicament es observar osteoconductividad l'empelt ossi i més partícules residuals d'aquest en el costat experimental. La tècnica dels EMC sembla ser tan eficaç com la tècnica de ROG en l'augment de l'amplada de les crestes atròfiques. Els defectes tractats amb els EMC mostrar una menor contracció de l'empelt ossi durant els 6 mesos de cicatrització.

L’insuffisance cardiaque est un problème de santé publique dans les pays développés, touchant 1 à 2% de la population générale, mais dont la prévalence atteint 10% après 70 ans. Les progrès thérapeutiques ont permis d’améliorer le pronostic des patients, notamment ceux ayant une altération de la fonction systolique ventriculaire gauche. Les troubles du rythme sont fréquents et nécessitent une pris en charge particulière au cours des situations d’insuffisance cardiaque. Cependant, il reste des questions non résolues : comment améliorer l’efficacité du traitement de l’insuffisance cardiaque à fonction systolique préservée, comment mieux sélectionner les patients pouvant bénéficier de la prévention primaire de la mort subite par un défibrillateur implantable, les patients âgés peuvent-ils bénéficier de la même prise en charge que les patients plus jeunes, et pour finir comment améliorer les résultats de l’ablation de fibrillation auriculaire dans les situations d’insuffisance cardiaque. Nous avons mis en place une étude prospective chez des patients présentant une dysfonction diastolique pour évaluer l’intérêt de l’algorithme de surveillance de l’apnée du sommeil disponible dans des stimulateurs cardiaques. En parallèle, nous avons analysé l’impact de l’évaluation par résonance magnétique des patients candidats à un défibrillateur sur la prédiction des évènements rythmiques, mais aussi le devenir des patients de plus de 75 ans appareillés avec un système de resynchronisation cardiaque. Enfin, nous nous sommes intéressés aux résultats d’un nouveau système de cartographie électroanatomique ultra-haute densité pour guider les procédures d’ablation de troubles du rythme supraventriculaires complexes chez des patients insuffisants cardiaques comparés à des patients contrôles
Heart failure is a major public health issue in developed countries, with a prevalence of 1-2% of global population, rising to 10% after 70 years of age. Therapeutic progresses have succeeded in improving patients’ prognosis, particularly in case of reduced left ventricular ejection fraction. Rhythm abnormalities are frequent, and need special consideration in case of heart failure. Meanwhile, there are still some gaps in the evidence: heart failure with preserved systolic function is complex and difficult to treat, primary prevention of sudden cardiac death is effective but there is a need to better select candidates, whether elderly patients should be treated as younger individuals, and finally how to improve outcomes of atrial fibrillation catheter ablation. Firstly, we have conducted a prospective study to evaluate the Sleep Apnea Monitoring algorithm provided in a novel pacemaker in patients with diastolic dysfunction. Besides, we analyzed whether magnetic resonance imaging could predict cardiac outcomes in patients with an implantable cardioverter defibrillator better than echocardiography. We also reported the outcomes of the cardiac resynchronization therapy in patients ≥75 years old compared to younger patients. Finally, we studied the results of a novel ultra-high density mapping system to guide ablation procedures of complex atrial arrhythmias in heart failure patients compared to controls

BACKGROUND: Adhesive capsulitis is an idiopathic disorder of the shoulder that is characterized by pain in combination with the gradual loss of passive and active range of motion. It is typically self-limiting, although the disease still remains poorly understood. However, there are several treatment modalities, both conservative and surgical, that provide significant clinical benefit for patients with adhesive capsulitis. Corticosteroid injections are an established conservative treatment method for adhesive capsulitis. Several studies have demonstrated that injections provide short-term benefits in terms of shoulder mobility and pain reduction. The intra-articular injections can be performed blindly (landmark) or with ultrasound (US) guidance. Physicians administer injections under US guidance in an attempt to improve the accuracy of the injection. However, it remains unclear whether US-guided injections relieve symptoms of adhesive capsulitis more effectively than landmark injections. OBJECTIVE: To compare the pain relief, self-reported function, and shoulder range of motion (ROM) outcomes of landmark versus US-guided corticosteroid injections for adhesive capsulitis. Methods: A total of 21 patients with adhesive capsulitis were randomized to receive either a landmark or US-guided intra-articular corticosteroid injection. Clinical outcome measures were documented at baseline, 6 weeks, and 12 weeks. These measures included a visual analog scale (VAS) for pain, the Single Assessment Numeric Evaluation (SANE) score for self-reported function, and passive shoulder ROM, including forward flexion, external rotation, and abduction. RESULTS: Both US-guided and landmark glenohumeral (GH) joint injections significantly improved VAS scores, SANE scores, and shoulder ROM outcomes. Improvement was maintained for all outcome measures in both groups throughout the 12 week treatment period. However, there were no significant differences seen in outcome measures between the two groups except that US-guided provided greater improvement in abduction at the 6 week follow-up (P = .004). CONCLUSIONS: This preliminary report found that there is no significant difference in the effectiveness of US-guided and landmark cortisone injection in terms of pain improvement, self-reported functions, and ROM outcomes for adhesive capsulitis.

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AIM: To demonstrate the benefits of fluoroscopy-guided intra-articular steroid injection in the hip with varying degrees of disease severity, and to investigate the financial aspects of the procedure and impact on waiting time. MATERIALS AND METHODS: A prospective study was undertaken of patients who underwent fluoroscopic intra-articular steroid injection over the 9-month study period. Comparative analysis of the Oxford hip pain score pre- and 6-8 weeks post-intra-articular injection was performed. Hip radiographs of all patients were categorised as normal, mild, moderate, or severe disease (four categories) based on the modified Kellgren-Lawrence severity scale, and improvement on the Oxford hip pain score on each of these four severity categories were assessed. RESULTS: Within the study cohort of 100 patients, the mean increase in post-procedure hip score of 7.32 points confirms statistically significant benefits of the therapy (p<0.001, 95% confidence interval: 5.55-9.09). There was no significant difference in pre-injection hip score or change in score between the four severity categories (p=0.51). Significant improvement in hip score (p<0.05) was demonstrated in each of the four severity categories 6-8 weeks post-injection. No associated complications were observed. CONCLUSION: The present study confirms that fluoroscopy-guided intra-articular steroid injection is a highly effective therapeutic measure for hip osteoarthritis across all grades of disease severity with significant cost savings and the potential to reduce waiting times.

Research report submitted to the Faculty of Health Sciences, University of the Witwatersrand, in partial fulfilment of the requirements for the degree of Master of Medicine, Clinical Microbiology Johannesburg 2018
Procalcitonin (PCT) is a biomarker used in sepsis to guide antibiotic duration of treatment. Clinical algorithms that utilise PCT have demonstrated value in reducing duration of antibiotic treatment in critically ill patients. There is lack of evidence regarding the utility of PCT-guided antibiotic algorithms in trauma patients and in patients from developing countries. A prospective study was conducted in the surgical trauma intensive care unit (ICU) at Charlotte Maxeke Johannesburg academic hospital from April 2014 to July 2015 in a two period cross-over design. Patients with suspected or confirmed sepsis were recruited consecutively in two periods of almost equal length. In the first period, 40 patients were recruited as controls and antibiotics were discontinued as per standard of care. In the second period, 40 patients were recruited into the intervention group and antibiotics were discontinued if the PCT decreased by ≥ 80% from the peak PCT level, or to an absolute value of less than 0.5 μg/L. The antibiotic duration of treatment was the primary outcome. Patients were followed up for 28 days from the first sepsis event. For the first sepsis event the intervention group had a mean antibiotic duration of 9.3 days while the control group had a mean duration of 10.9 days (p=0.10). The mean duration of treatment was 12.0 days for a second episode of sepsis in the control group and 9.6 days in the intervention group (p=0.09). Clinician compliance to the PCT algorithm was 62.5%. The intervention group had more antibiotic free days (7.8 days) compared to the control group (3.9 days) (p=0.004). The length of ICU stay and length of hospital stay for the two groups were similar. The in-hospital mortality was reduced in the intervention group (15%) compared to the control group (30%). Our data supports the use of PCT-guided algorithms for antibiotic stewardship in surgical trauma patients. Clinician compliance would most likely increase the benefits observed in our study.
MT 2020