177 resultados para Foreign Relations


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Ce livre traque un objet jusqu'ici resté dans l'ombre de l'histoire, le voisinage en milieu urbain. Dans les villes de l'Europe en voie d'industrialisation et d'urbanisation massive, du XVIIIe au XXe siècle, comment approcher les cohabitations quotidiennes ? De la contrainte à l'accommodement, de la sociabilité choisie à la promiscuité subie, des crispations construites aux frontières érigées, de la dénonciation au crime, l'histoire, l'anthropologie et l'urbanisme sont mobilisées pour cette étude novatrice.

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Une méthode de marquage radioactif simultané de deux musaraignes est décrite. Comme instruments, 2 compteurs a scintillation portatifs et un dispositif d'enregistrement automatique à 20 sondes ont été utilisés. Les musaraignes ont été respectivement marquées avec un filament de 100 µ Ci et 600 µ Ci. Avant l'enregistrement simultané il faut déterminer pour chaque individu le domaine vital et l'emplacement des nids et calibrer les instruments. Cette technique est appliquée à une population de Crocidura russula. Elle permet d'étudier les relations spatio-temporelles des individus durant leur activité et repos (occupation commune d'un nid).

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Enterococcal implant-associated infections are difficult to treat because antibiotics generally lack activity against enterococcal biofilms. We investigated fosfomycin, rifampin, and their combinations against planktonic and adherent Enterococcus faecalis (ATCC 19433) in vitro and in a foreign-body infection model. The MIC/MBClog values were 32/>512 μg/ml for fosfomycin, 4/>64 μg/ml for rifampin, 1/2 μg/ml for ampicillin, 2/>256 μg/ml for linezolid, 16/32 μg/ml for gentamicin, 1/>64 μg/ml for vancomycin, and 1/5 μg/ml for daptomycin. In time-kill studies, fosfomycin was bactericidal at 8× and 16× MIC, but regrowth of resistant strains occurred after 24 h. With the exception of gentamicin, no complete inhibition of growth-related heat production was observed with other antimicrobials on early (3 h) or mature (24 h) biofilms. In the animal model, fosfomycin alone or in combination with daptomycin reduced planktonic counts by ≈4 log10 CFU/ml below the levels before treatment. Fosfomycin cleared planktonic bacteria from 74% of cage fluids (i.e., no growth in aspirated fluid) and eradicated biofilm bacteria from 43% of cages (i.e., no growth from removed cages). In combination with gentamicin, fosfomycin cleared 77% and cured 58% of cages; in combination with vancomycin, fosfomycin cleared 33% and cured 18% of cages; in combination with daptomycin, fosfomycin cleared 75% and cured 17% of cages. Rifampin showed no activity on planktonic or adherent E. faecalis, whereas in combination with daptomycin it cured 17% and with fosfomycin it cured 25% of cages. Emergence of fosfomycin resistance was not observed in vivo. In conclusion, fosfomycin showed activity against planktonic and adherent E. faecalis. Its role against enterococcal biofilms should be further investigated, especially in combination with rifampin and/or daptomycin treatment.

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The geologic structures and metamorphic zonation of the northwestern Indian Himalaya contrast significantly with those in the central and eastern parts of the range, where the high-grade metamorphic rocks of the High Himalayan Crystalline (HHC) thrust southward over the weakly metamorphosed sediments of the Lesser Himalaya along the Main Central Thrust (MCT). Indeed, the hanging wall of the MCT in the NW Himalaya mainly consists of the greenschist facies metasediments of the Chamba zone, whereas HHC high-grade rocks are exposed more internally in the range as a large-scale dome called the Gianbul dome. This Gianbul dome is bounded by two oppositely directed shear zones, the NE-dipping Zanskar Shear Zone (ZSZ) on the northern flank and the SW-dipping Miyar Shear Zone (MSZ) on the southern limb. Current models for the emplacement of the HHC in NW India as a dome structure differ mainly in terms of the roles played by both the ZSZ and the MSZ during the tectonothermal evolution of the HHC. In both the channel flow model and wedge extrusion model, the ZSZ acts as a backstop normal fault along which the high-grade metamorphic rocks of the HHC of Zanskar are exhumed. In contrast, the recently proposed tectonic wedging model argues that the ZSZ and the MSZ correspond to one single detachment system that operates as a subhorizontal backthrust off of the MCT. Thus, the kinematic evolution of the two shear zones, the ZSZ and the MSZ, and their structural, metamorphic and chronological relations appear to be diagnostic features for discriminating the different models. In this paper, structural, metamorphic and geochronological data demonstrate that the MSZ and the ZSZ experienced two distinct kinematic evolutions. As such, the data presented in this paper rule out the hypothesis that the MSZ and the ZSZ constitute one single detachment system, as postulated by the tectonic wedging model. Structural, metamorphic and geochronological data are used to present an alternative tectonic model for the large-scale doming in the NW Indian Himalaya involving early NE-directed tectonics, weakness in the upper crust, reduced erosion at the orogenic front and rapid exhumation along both the ZSZ and the MSZ.

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Crystallisation of hydrous mafic magmas at high pressure is a subject of numerous petrologic and experimental studies since the last century and is mainly related to the process of continental crust formation and the possible link between mantle derived melts and low pressure granitoids. Albeit the sequence of crystallization is well constrained by experimental studies, the origin of exposed lower crustal rocks exposed on the earth surface is controversial. Ones line of argument is favouring high pressure crystallization of dry or wet mafic magmas, whereas others invoke partial melting of pre-existing crust. Therefore studies involving field, textural and chemical observations of exposed lower crust such as in Kohistan (Pakistan) or Talkeetna (Alaska) are crucial to understand the continental crust formation processes via arc magmatism. Epidote-bearing gabbros are very sparse and always associated with the deep part of continental crust (>30 km) as in the Kohistan Arc Complex (Pakistan) or in the Chelan Complex (western U.S.). Magmatic epidote is restricted to a small temperature interval above the water-saturated solidus of MORB and represent the last crystallizing liquids in lower crustal regions. However, epidote and melt stability at lower crustal pressures are not clearly established.¦The Chelan complex (western U.S.) at the base of the Cascadian Arc is composed mainly by peraluminous tonalité associated with gabbroic and ultramafic rocks and was traditionally interpreted as a migmatitic terrain. However field, chemical and mineralogical observations rather suggest a magmatic origin and point to a protracted crystallization at intermediate to high pressure ~ 1.0 GPa dominated by amphibole fractionation and followed by isobaric cooling down to 650°C. Crystal fractionation modelling using whole rock composition and field constraints is able to generate peraluminous tonalité. The modelled crystallisation sequence and the volume proportions are in agreement with experimental studies performed at these pressures. The Chelan complex was thus not formed during a partial melting event, but represent the sequence of crystallisation occurring at the base of the crust. Massive fractionation of hornblende is able to generate peraluminous tonalité without significant assimilation of crustal rock.¦Similarly to the Chelan complex, the base of the Kohistan arc is composed of cumulates derived by high pressure crystallization of hydrous magma. In garnet gabbros, epidote occurs as magmatic phase, crystallising from hydrous interstitial melt trapped between grain boundaries at lower crustal pressures (Ρ ~ 1.2 GPa) for temperature of (650-700 °C). Trace and REE signature in epidote indicate that epidote was formed through peritectic reaction involving garnet, clinopyroxene and plagioclase. At the beginning of the crystallisation epidote signature is dominated by REE content in the melt, whereas at the end the signature is dominated by reacting phases. Melt in equilibrium with epidote inferred from the partition coefficients available is similar to intrusive tonalité up the section indicating that hydrous melt was extracted from the garnet gabbros. In some gabbros epidote shows single homogeneous compositions, while in others coexisting epidote have different compositions indicating the presence of solvi along the Al-Fe3+ join. The overgowths are only observed in presence of paragonite in the assemblage, suggesting high water content. At high water content, the hydrous solidus is shift to lower temperature and probably intersects the solvi observed along the Al-Fe3+ join. Therefore, several compositions of epidote is stable at high water content.¦-¦La composition chimique de la croûte continentale est considérée comme similaire à celle du magmatisme calco-alcalin de marge continentale active (enrichissement en éléments mobiles dans les fluides, anomalies négatives en Nb, Ta et éléments à haut potentiel électronique, etc...). Cependant la nature andésitique de la croûte continentale (Si02 > 60 wt%), résultant des nombreuses intrusions de granitoïdes dans la croûte supérieure, est sujette à polémique et le lien entre les magmas dérivés du manteau et les roches évoluées de faible profondeur n'est pas clairement établi (fusion partielle de croûte basaltique, cristallisation fractionnée à haute pression, etc...).¦Les affleurements de croûte profonde sont rares mais précieux, car ils permettent d'observer les phénomènes se passant à grande profondeur. Le complexe de Chelan (Washington Cascades) en est un exemple. Formé à environ 30 km de profondeur, il est composé de roches gabbroïques et ultramafiques, ainsi que de tonalités, qui furent souvent interprétés comme le produit de la fusion partielle de la croûte. Cependant, les relations de terrain, la chimie des éléments majeurs et des éléments traces sont cohérentes avec l'évolution d'un complexe magmatique mafique dans la croûte profonde ou moyenne ( 1.0 GPa), dominée par le fractionnement de l'amphibole. Après son emplacement, le complexe a subi un refroidissement isobare jusqu'à des températures de l'ordre de 650 °C, déduit de la composition chimique des minéraux. Un bilan de masse contraint pax les observations de terrain permet de calculer la séquence et les volumes de fractionnement. Les faciès évolués légèrement hyperalumineux observés sur le terrain peuvent être générés par la cristallisation de 3 % de websterite à olivine, 12 % d'hornblendite à pyroxène 33 % d'hornblendite, 19 % de gabbros, 15 % de diorite et 2 % de tonalité. Nous montrons ainsi qu'une série de fractionnement contrôlée par l'amphibole permet de générer des tonalités sans assimilation de matériel crustal et l'exemple de Chelan illustre la viabilité de ce processus dans la formation de croûte continentale.¦Les réactions proches du solidus saturé en H20 dans les systèmes basaltiques à des pressions élevées restent énigmatiques. Diverses expériences tendent à montrer que l'épidote est stable dans ces conditions, mais rarement observée (décrite ?) comme phase primaire dans les systèmes naturels. Les épidotes trouvées dans les gabbros de Jijal (nord-Pakistan) montrent des textures de type .magmatique telles qu'observées dans les roches évoluées. Le contenu en terres rares de ces épidotes est très variable allant de signatures enrichies en terres rares légères impliquant la présence de liquide interstitiel à des signatures complètement déprimées en ces mêmes éléments, évoquant une cristallisation en coexistence avec du grenat. Ces diverses signatures reflètent un chemin de cristallisation en présence de liquide interstitiel et enregistrent des réactions péritectiques impliquant grenat, clinopyroxene et plagioclase à des pressions de ~ 1.2 GPa pour des températures de 650-700 °C. Cependant dans quelques échantillons deux ou trois compositions d'épidotes coexistent démontrant la présence de lacunes d'immiscibilité le long de la solution solide épidote-clinozoïsite. La forte teneur en H20 du liquide magmatique est certainement à l'origine de la coexistence de deux compositions distinctes.

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Metallic foreign bodies are rarely found in the maxillary sinus, and usually they have a dental origin.Potential complications related to foreign bodies include recurrent sinusitis, rhinolith formation, cutaneous fistula,chemical poisoning, facial neuralgic pain and even malignancies.Two main surgical approaches are currently used for the removal of foreign bodies in the maxillary sinus: the bone flap and the endoscopic sinus techniques. We are reporting two unusual cases of large high-velocity foreign bodies removed by a modified maxillary lateral antrotomy,with free bone flap repositioning and fixation with a titanium miniplate.

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The activity of dalbavancin, a representative of the lipoglycopeptide antibiotics, alone and in combination with rifampicin, was investigated against meticillin-resistant Staphylococcus aureus (MRSA) in a foreign-body infection model in guinea pigs. The MIC, MBC and time-kill profile of dalbavancin were determined for MRSA ATCC 43300 in the logarithmic (MBClog) and stationary (MBCstat) growth phases. The pharmacokinetic profile of dalbavancin was determined in sterile cage fluid in guinea pigs. The activity of intraperitoneal dalbavancin (40, 60 or 80mg/kg as a single dose), rifampicin (12.5mg/kg/12h for 4 days) and their combination was assessed against planktonic and biofilm MRSA. The MIC of dalbavancin was 0.078mg/L; MBClog and MBCstat were both >128Ã- MIC. In time-kill studies, bacterial reduction of 3log10CFU/mL was achieved after 48h at â0/00¥32Ã- MIC (logarithmic growth) and at â0/00¥1Ã- MIC (stationary growth). Dalbavancin was neither synergistic nor antagonistic with rifampicin, and prevented the emergence of rifampicin resistance in vitro. The half-life of dalbavancin in cage fluid was 35.8-45.4h and the concentration remained above the MIC of MRSA during 7 days after a single dose. Dalbavancin reduced planktonic MRSA in cage fluid at high dose (60mg/kg and 80mg/kg) but failed to eradicate biofilm MRSA from cages. In combination with rifampicin, dalbavancin at 80mg/kg cured 36% of infected cages, and emergence of rifampicin resistance was completely prevented. Dalbavancin at 80mg/kg and in combination with rifampicin eradicated approximately one-third of cage-associated MRSA infections and prevented emergence of rifampicin resistance.