983 resultados para Proportional valves


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Background: The purpose of the work reported here is to test reliable molecular profiles using routinely processed formalin-fixed paraffin-embedded (FFPE) tissues from participants of the clinical trial BIG 1-98 with a median follow-up of 60 months. Methods: RNA from fresh frozen (FF) and FFPE tumor samples of 82 patients were used for quality control, and independent FFPE tissues of 342 postmenopausal participants of BIG 1-98 with ER-positive cancer were analyzed by measuring prospectively selected genes and computing scores representing the functions of the estrogen receptor (eight genes, ER_8), the progesterone receptor (five genes, PGR_5), Her2 (two genes, HER2_2), and proliferation (ten genes, PRO_10) by quantitative reverse transcription PCR (qRT-PCR) on TaqMan Low Density Arrays. Molecular scores were computed for each category and ER_8, PGR_5, HER2_2, and PRO_10 scores were combined into a RISK_25 score. Results: Pearson correlation coefficients between FF- and FFPE-derived scores were at least 0.94 and high concordance was observed between molecular scores and immunohistochemical data. The HER2_2, PGR_ 5, PRO_10 and RISK_25 scores were significant predictors of disease free-survival (DFS) in univariate Cox proportional hazard regression. PRO_10 and RISK_25 scores predicted DFS in patients with histological grade II breast cancer and in lymph node positive disease. The PRO_10 and PGR_ 5 scores were independent predictors of DFS in multivariate Cox regression models incorporating clinical risk indicators; PRO_10 outperformed Ki-67 labeling index in multivariate Cox proportional hazard analyses. Conclusions: Scores representing the endocrine responsiveness and proliferation status of breast cancers were developed from gene expression analyses based on RNA derived from FFPE tissues. The validation of the molecular scores with tumor samples of participants of the BIG 1-98 trial demonstrates that such scores can serve as independent prognostic factors to estimate disease free survival (DFS) in postmenopausal patients with estrogen receptor positive breast cancer.

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A differentiated reconstruction of palaeolimnologic, -environmental, and -climatic conditions is presented for the Middle Miocene long-term freshwater lake (14.3 to 13.5 Ma) of the Steinheim basin, on the basis of a combined C, 0, and Sr isotope study of sympatric skeletal fossils of aquatic and terrestrial organisms from the lake sediments. The oxygen isotope composition for lake water of the Steinheim basin (delta O-18(H2O) = +2.0 +/- 0.4 parts per thousand VSMOW, n = 6) was reconstructed from measurements of delta O-18(PO4) of aquatic turtle bones. The drinking water calculated from the enamel of large mammals (proboscideans, rhinocerotids, equids, cervids, suids) has delta O-18(H2O) values (delta(OH2O)-O-18 = -5.9 +/- 1.7 parts per thousand VSMOW, n = 31) typical for Middle Miocene meteoric water of the area. This delta O-18(H2O) value corresponds to a mean annual air temperature (MAT) of 18.8 +/- 3.8 degrees C, calculated using a modem-day delta(OH2O)-O-18-MAT relation. Hence, large mammals did not use the lake water as principal drinking water. In contrast, small mammals, especially the then abundant pika Prolagus oeningensis drank from O-18-enriched water sources (delta O-18(H2O) = +2.7 +/- 2.3 parts per thousand VSMOW, n = 7), such as the lake water. Differences in Sr and 0 isotopic compositions between large and small mammal teeth indicate different home ranges and drinking behaviour and support migration of some large mammals between the Swabian Alb plateau and the nearby Molasse basin, while small mammals ingested their food and water locally. Changes in the lake level, water chemistry, and temperature were inferred using isotopic compositions of ostracod and gastropod shells from a composite lake sediment profile. Calcitic ostracod valves (Ilyocypris binocularis; delta O-18 = +1.7 +/- 1.2 parts per thousand VPDB, delta C-18 = -0.5 +/- 0.9 parts per thousand, VPDB, n = 68) and aragonitic, gastropod shells (Gyraulus spp.; delta O-18 = +2.0 +/- 13 parts per thousand VPDB, delta C-13 = -1.1 +/- 1.3 parts per thousand VPDB, n = 89) have delta O-18 and delta C-13 values similar to or even higher than those of marine, carbonates. delta C-13 values:of the biogenic carbonates parallel lake level fluctuations while delta O-18 values scatter around +2 +/- 2 parts per thousand and reflect the short term variability of meteoric water inflow vs. longer term evaporation. Sr-87/Sr-86 ratios of aragonitic Gyraulus spp. gastropod shells parallel the lake level fluctuations, reflecting variable inputs of groundwater and surface waters. Using a water delta O-18(H2O) value of +2.0 parts per thousand VSMOW, water temperatures calculated from skeletal tissue delta O-18 values of ostracods are 16.7 +/- 5.0 degrees C, gastropods 20.6 +/- 5.6 degrees C, otoliths 21.8 +/- 1.4 degrees C, and fish teeth 17.0 +/- 2.7 degrees C. The calculated MAT (similar to 19 degrees C), lake water temperatures (similar to 17 to 22 degrees C) and the O-18-enriched water compositions are indicative of warm-temperate climatic conditions, possibly with a high humidity during this period. Vegetation in the area surrounding the basin was largely of the C-3-type, as indicated by carbon isotopic compositions of tooth enamel from large mammals (delta C-13 = -11.1 +/- 1.1 parts per thousand VPDB, n = 40). (c) 2006 Elsevier B.V. All rights reserved.

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Several Brazilian Aedes aegypti populations are resistant to the larvicidae temephos. Methoprene, that inhibits adult emergence, is one of the alternatives envisaged by the Brazilian Dengue Control Program (PNCD). However, at Brazil vector infestation rates are measured through larvae indexes and it has been claimed that methoprene use in the field could face operational problems. In order to define a standardized protocol, methoprene effect was evaluated in laboratory conditions after continuous exposure of larvae (Rockefeller strain) to a methoprene formulation available to the PNCD. Methoprene-derived mortality occurs mainly at the pupa stage and pupa development is inversely proportional to methoprene concentration. Number and viability of eggs laid by treated and control females are equivalent. A methoprene dose-dependent delay in the development was noted; however, b correlations were found for total mortality or adult emergence inhibition if data obtained when all control mosquitoes have emerged are compared to data obtained when methoprene-treated groups finish development. The cumulative record of total methoprene-induced mortality at the time control adults emerge is proposed for routine evaluation of field populations. Mortality of all specimens, but not of larva, could account for adult emergence inhibition, confirming the inadequacy of larvae indexes to evaluate methoprene effect.

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OBJECTIVES: Reassessment of ongoing antibiotic therapy is an important step towards appropriate use of antibiotics. This study was conducted to evaluate the impact of a short questionnaire designed to encourage reassessment of intravenous antibiotic therapy after 3 days. PATIENTS AND METHODS: Patients hospitalized on the surgical and medical wards of a university hospital and treated with an intravenous antibiotic for 3-4 days were randomly allocated to either an intervention or control group. The intervention consisted of mailing to the physician in charge of the patient a three-item questionnaire referring to possible adaptation of the antibiotic therapy. The primary outcome was the time elapsed from randomization until a first modification of the initial intravenous antibiotic therapy. It was compared within both groups using Cox proportional-hazard modelling. RESULTS: One hundred and twenty-six eligible patients were randomized in the intervention group and 125 in the control group. Time to modification of intravenous antibiotic therapy was 14% shorter in the intervention group (adjusted hazard ratio for modification 1.28, 95% CI 0.99-1.67, P = 0.06). It was significantly shorter in the intervention group compared with a similar group of 151 patients observed during a 2 month period preceding the study (adjusted hazard ratio 1.17, 95% CI 1.03-1.32, P = 0.02). CONCLUSION: The results suggest that a short questionnaire, easily adaptable to automatization, has the potential to foster reassessment of antibiotic therapy.

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ABSTRACT : Ostracods are benthic microcrustaceans enclosed in low-Mg calcite bivalves. Stable isotope compositions, Mg/Ca, and Sr/Ca ratios of ostracod fossil valves have proven useful to reconstruct past environmental conditions. Yet, several discrepancies persist and the influence of many factors remains unclear. It is the aim of this study to improve the use of ostracod valve geochemistry as palaeoenvironmental proxies by examining the extent of isotope fractionation and trace element partitioning during valve calcification. To achieve this, the environmental parameters (pH, temperature) and chemical composition of water (C-and O-isotope composition and calcium, magnesium, and strontium content) were measured at sites where living ostracods were sampled. The sampling was on a monthly basis over the course of one year at five different water depths (2, 5, 13, 33, and 70 m) in Lake Geneva, Switzerland. The one-year sampling enabled collection of environmental data for bottom and interstitial pore water. In littoral to sublittoral zones, C-isotope composition of DIC and the Mg/Ca and Sr/Ca ratios of water are found to vary concomitantly with water temperature. This is due to the precipitation of calcite, which is induced by higher photosynthetic activity as temperature and/or solar radiation intensify in summer. In deeper zones, environmental parameters remain largely constant throughout the year. Variations of pH, DIC concentrations and C-isotope compositions in interstitial water result from aerobic as well as anaerobic respiration, calcite dissolution and methanogenesis. Bathymetric distribution, life cycles, and habitats were derived for 15 ostracod species and are predominantly related to water temperature and sediment texture. O-isotope compositions of ostracod valves in Lake Geneva reflect that of water and temperature. However, offsets of up to 3 permil are observed in comparison with proposed inorganic calcite precipitation equilibrium composition. Deprotonation of HCO3- and/or salt effect at crystallisation sites may explain the disequilibrium observed for O-isotopic compositions. C-isotope compositions of ostracod valves are not as well constrained and appear to be controlled by a complex interaction between habitat preferences and seasonal as well as spatial variations of the DIC isotope composition. For infaunal forms, C-isotope compositions reflect mainly the variation of DIC isotope composition in interstitial pore waters. For epifaunal forms, C-isotope compositions reflect the seasonal variation of DIC isotope compositions. C-isotope compositions of ostracod valves is at equilibrium with DIC except for a small number of species (L. inopinata, L. sanctipatricii and possibly C. ophtalmica, and I. beauchampi). Trace element uptake differs considerably from species to species. For most epifaunal forms, trace element content follows the seasonal cycle, recording temperature increases and/or variations of Mg/Ca and Sr/Ca ratios of water. In contrast, infaunal forms are predominantly related to sediment pore water chemistry. RÉSUMÉ EN FRANÇAIS : Les ostracodes sont de petits crustacés benthiques qui possèdent une coquille faite de calcite à faible teneur en magnésium. La composition isotopique et les rapports Mg/Ca et Sr/Ca d'ostracodes fossiles ont été utilisés maintes fois avec succès pour effectuer des reconstructions paléoenvironnementales. Néanmoins, certains désaccords persistent sur l'interprétation de ces données. De plus, l'influence de certains facteurs pouvant biaiser le signal reste encore inconnue. Ainsi, le but de cette étude est de rendre plus performant l'emploi de la composition géochimique des ostracodes comme indicateur paléoenvironnemental. Pour réaliser cela, cinq sites situés dans le Léman à 2, 5, 13, 33 et 70 m de profondeur ont été choisis pour effectuer les échantillonnages. Chaque site a été visité une fois par mois durant une année. Les différents paramètres environnementaux (pH, température) ainsi que la composition géochimique de l'eau (composition isotopique de l'oxygène et du carbone ainsi que teneur en calcium, magnésium et strontium) ont été déterminés pour chaque campagne. Des ostracodes vivants ont été récoltés au cinq sites en même temps que les échantillons d'eau. Ce travail de terrain a permis de caractériser la géochimie de l'eau se trouvant juste au-dessus des sédiments ainsi que celle de l'eau se trouvant dans les interstices du sédiment. Dans les zones littorales à sublittorales, la composition isotopique du carbone inorganique dissout (CID) ainsi que les rapports Mg/Ca et Sr/Ca de l'eau varient linéairement avec la température. Ceci peut être expliqué par la précipitation de calcite qui est contrôlée par l'activité photosynthétique, variant elle même linéairement avec la température. Dans les zones plus profondes, les paramètres environnementaux restent relativement constants tout au long de l'année. Les variations du pH, de la concentration et de la composition isotopique du CID dans les sédiments résultent de la libération de carbone engendrée par la dégradation de la matière organique avec présence d'oxygène ou via réduction de nitrates et de sulfates, par la dissolution de carbonates, ainsi que par la méthanogenèse. La distribution bathymétrique, le cycle de vie ainsi que l'habitat de 15 espèces ont été déterminés. Ceux-ci sont principalement reliés à la température de l'eau et à la texture des sédiments. La composition isotopique de l'oxygène des valves d'ostracodes reflète celle de l'eau et la température qui régnait lors de la calcification. Néanmoins, des écarts pouvant aller jusqu'à 3 0/00 par rapport à l'équilibre théorique ont été obtenus. La déprotonation de HCO3 ou un 'effet de sel' pourrait être à l'origine du déséquilibre observé. La composition isotopique du carbone des valves d'ostracodes n'est pas aussi bien cernée. Celle-ci semble être principalement contrôlée par une interaction complexe entre l'habitat des ostracodes et les variations saisonnières et spatiales de la composition isotopique du CID. Pour les espèces endofaunes, la composition isotopique du carbone reflète principalement la variation de la composition isotopique du CID à l'intérieur des sédiments. Pour les formes épifaunes, c'est la variation saisonnière de la composition du CID qui contrôle celle de la coquille des ostracodes. En général, la composition isotopique du carbone des valves d'ostracodes est en équilibre avec celle de CID, hormis pour quelques rares espèces (L. inopinata, L. sanctipatricii et peut-être C. ophtalmica et I. beauchampi). L'incorporation des éléments traces diffère passablement d'une espèce à l'autre. Pour la plupart des espèces épifaunes, la teneur en éléments traces des coquilles reflète les variations saisonnières. Ces espèces semblent enregistrer les variations soit de la température soit des rapports Mg/Ca et Sr/Ca de l'eau. La teneur en élément traces des formes infaunales, au contraire, est principalement reliée à la chimie de l'eau interstitielle. RÉSUMÉ GRAND-PUBLIC : La connaissance de l'évolution du climat dans le futur est primordiale pour notre société, car elle permet de développer différentes stratégies pour faire face aux problèmes engendrés pas le changement climatique : stratégies environnementale, humanitaire, ou encore économique. Cette problématique est actuellement, à juste titre, sujet d'une vive préoccupation. La géologie peut-elle contribuer à l'effort communautaire entrepris? Naturellement, ce sont les climatologues qui sont sur le devant de la scène. Il n'empêche que ces derniers, pour pouvoir prédire l'avenir, doivent s'appuyer sur le passé. La géologie est alors d'un grand intérêt car c'est effectivement la seule science qui permette d'estimer les variations climatiques à grande échelle sur de longues périodes. Ainsi, voulant moi-même contribuer aux recherches menées dans ce domaine, je me suis tourné à la fin de mes études vers la paléoclimatologie, science qui a pour but de reconstruire le climat des temps anciens. Nous nous sommes rendu compte que l'évolution climatique de la région où nous habitons n'avait pas encore fait le sujet d'études approfondies. Il est pourtant important de connaître la variation locale des changements climatiques pour obtenir des modèles climatiques fiables. En conséquence, un vaste projet a vu le jour : reconstruire, à l'aide des sédiments du lac Léman, les variations paléoclimatiques et paléo-environnementales depuis le retrait du Glacier de Rhône, il y a environ 15'000 ans, jusqu'à nos jours. Pour ce genre de travail, la géochimie, qui est une forme de chimie, utilisée en science de la terre regroupant la chimie classique et la chimie isotopique, est une alliée particulièrement efficace. Elle permet en effet, via différentes mesures faites sur des archives géologiques (par exemple des fossiles ou des sédiments) d'obtenir des informations, souvent quantitatives, sur les conditions (le climat, la flore ou encore la bio productivité, etc...) qui régnaient il y a fort longtemps. Les coquilles d'ostracodes, qui sont de petits animaux vivant au fond des lacs, sont une des archives les plus prometteuses. Ces animaux sont des petits crustacés s'entourant d'une coquille calcaire qu'ils sécrètent eux-mêmes. A la mort de l'animal, la coquille est intégrée dans les sédiments et reste intacte à travers les âges. Des études ont montré qu'en analysant la géochimie de ces coquilles fossiles, il est possible de reconstruire les conditions environnementales qui régnaient à l'époque de vie de ces fossiles. Cette démarche nécessite qu'une condition bien précise soit remplie: la composition géochimique de la coquille doit enregistrer de manière fidèle la chimie de l'eau et/ou la température de l'eau présentes au moment de la sécrétion de la coquille. Le but spécifique de notre recherche a précisément été d'étudier la façon dont la chimie de l'eau ainsi que sa température sont enregistrées dans la coquillé des ostracodes. Une fois les relations entre ces divers paramètres dans l'étant actuel du système établies, il sera alors possible de les utiliser pour interpréter des données issues de coquilles fossiles. Pour ce faire, nous avons mesuré la température de l'eau de manière continue et récolté mensuellement des échantillons d'eau et des ostracodes vivants pendant une année. Cinq sites situés à 2, 5, 13, 33 et 70 mètres de profondeur ont été choisis pour effectuer ces échantillonnages dans le Léman. Le travail de terrain nous a amené à étudier la biologie de 15 espèces. Nous avons pu établir la profondeur à laquelle vivent ces animaux, leur période de développement ainsi que leur habitat respectifs. Ces résultats ont permis de mieux cerner la relation qu'il existe entre la chimie de l'eau, sa température et la composition géochimique des coquilles d'ostracodes. Nous avons ainsi pu confirmer que les coquilles d'ostracodes enregistrent de manière fidèle la composition chimique et isotopique de l'eau. De même, nous avons pu établir de manière plus précise l'effet de la température sur la géochimie des coquilles. Néanmoins, les relations trouvées entre ces trois éléments sont plus complexes pour certaines espèces, cette complexité étant souvent liée à un caractère spécifique de leur écologie. Nous avons mis en lumière certains effets qui biaisent les résultats et défini précisément les conditions dans lesquelles on peut s'attendre à avoir des difficultés dans leur interprétation. Maintenant que nous avons établi les relations entre le climat actuel et la composition géochimique des coquilles d'ostracodes actuels, nous pouvons, sur la base de ce modèle, reconstruire le climat depuis le retrait du Glacier du Rhône jusqu'à nos jours à l'aide d'ostracodes fossiles. Mais cela est une autre histoire et fera, je l'espère, le sujet de nos futures recherches.

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The mature oocysts of Eimeria lepidosirenis n.sp. are described in faeces removed from the lower region of the intestine of a single specimen of the South American lungfish Lepidosiren paradoxa, from Belém, state of Pará, Amazonian Brazil. Oocysts with endogenous sporulation: spherical to slightly subspherical, 30.8 × 30.3 µm (28.1 × 25.9 -33.3 × 31.8), shape-index (ratio length/width) 1.0, n = 25. Oocyst wall a very thin, single layer approximately 0.74 µm thick, smooth, colourless, with no micropyle and rapidly breaking down to release the sporocysts. Oocyst residuum a bulky ovoid to spherical mass of approximately 20.0 × 15 µm, composed of fine granules and larger globules and enclosed by a very fine membrane: no polar bodies seen. Sporocysts 15.5 × 9.0 µm (14.5 × 8.0 16.0 × 9.0), shape index 1.7 (1.6-1.8), n = 30, ovoid, with one extremity rather pointed and with a very delicate Stieda body but no sub-Stieda body: sporocyst wall a single extremely thin layer with no valves. Sporocyst residuum a spherical to ovoid mass of approximately 5.0 × 4.0 µm, composed of fine granules and small globules and enclosed by a very fine membrane. Sporozoites strongly recurved at their ends and apparently with only a single refractile body. Site of development in the host uncertain: no evidence of endogenous stages was found in fresh scrapings and stained smears of the intestinal epithelium.

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CONTEXT: Infection of implantable cardiac devices is an emerging disease with significant morbidity, mortality, and health care costs. OBJECTIVES: To describe the clinical characteristics and outcome of cardiac device infective endocarditis (CDIE) with attention to its health care association and to evaluate the association between device removal during index hospitalization and outcome. DESIGN, SETTING, AND PATIENTS: Prospective cohort study using data from the International Collaboration on Endocarditis-Prospective Cohort Study (ICE-PCS), conducted June 2000 through August 2006 in 61 centers in 28 countries. Patients were hospitalized adults with definite endocarditis as defined by modified Duke endocarditis criteria. MAIN OUTCOME MEASURES: In-hospital and 1-year mortality. RESULTS: CDIE was diagnosed in 177 (6.4% [95% CI, 5.5%-7.4%]) of a total cohort of 2760 patients with definite infective endocarditis. The clinical profile of CDIE included advanced patient age (median, 71.2 years [interquartile range, 59.8-77.6]); causation by staphylococci (62 [35.0% {95% CI, 28.0%-42.5%}] Staphylococcus aureus and 56 [31.6% {95% CI, 24.9%-39.0%}] coagulase-negative staphylococci); and a high prevalence of health care-associated infection (81 [45.8% {95% CI, 38.3%-53.4%}]). There was coexisting valve involvement in 66 (37.3% [95% CI, 30.2%-44.9%]) patients, predominantly tricuspid valve infection (43/177 [24.3%]), with associated higher mortality. In-hospital and 1-year mortality rates were 14.7% (26/177 [95% CI, 9.8%-20.8%]) and 23.2% (41/177 [95% CI, 17.2%-30.1%]), respectively. Proportional hazards regression analysis showed a survival benefit at 1 year for device removal during the initial hospitalization (28/141 patients [19.9%] who underwent device removal during the index hospitalization had died at 1 year, vs 13/34 [38.2%] who did not undergo device removal; hazard ratio, 0.42 [95% CI, 0.22-0.82]). CONCLUSIONS: Among patients with CDIE, the rate of concomitant valve infection is high, as is mortality, particularly if there is valve involvement. Early device removal is associated with improved survival at 1 year.

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Patients with glioblastoma (GBM) have variable clinical courses, but the factors that underlie this heterogeneity are not understood. To determine whether the presence of the telomerase-independent alternative lengthening of telomeres (ALTs) mechanism is a significant prognostic factor for survival, we performed a retrospective analysis of 573 GBM patients. The presence of ALT was identified in paraffin sections using a combination of immunofluorescence for promyelocytic leukemia body and telomere fluorescence in situ hybridization. Alternative lengthening of telomere was present in 15% of the GBM patients. Patients with ALT had longer survival that was independent of age, surgery, and other treatments. Mutations in isocitrate dehydrogenase (IDH1mut) 1 frequently accompanied ALT, and in the presence of both molecular events, there was significantly longer overall survival. These data suggest that most ALT+ tumors may be less aggressive proneural GBMs, and the better prognosis may relate to the set of genetic changes associated with this tumor subtype. Despite improved overall survival of patients treated with the addition of chemotherapy to radiotherapy and surgery, ALT and chemotherapy independently provided a survival advantage, but these factors were not found to be additive. These results suggest a critical need for developing new therapies to target these specific GBM subtypes.

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Dans les dernières années du 20ème siècle, l'aluminium a fait l'objet de beaucoup de communications outrancières et divergentes cautionnées par des scientifiques et des organismes faisant autorité. En 1986, la société PECHINEY le décrète perpétuel tel le mouvement « L'aluminium est éternel. Il est recyclable indéfiniment sans que ses propriétés soient altérées », ce qui nous avait alors irrité. Peu de temps après, en 1990, une communication tout aussi outrancière et irritante d'une grande organisation environnementale, le World Wild Fund, décrète que « le recyclage de l'aluminium est la pire menace pour l'environnement. Il doit être abandonné ». C'est ensuite à partir de la fin des années 1990, l'explosion des publications relatives au développement durable, le bien mal nommé. Au développement, synonyme de croissance obligatoire, nous préférons société ou organisation humaine et à durable, mauvaise traduction de l'anglais « sustainable », nous préférons supportable : idéalement, nous aurions souhaité parler de société durable, mais, pour être compris de tous, nous nous sommes limités à parler dorénavant de développement supportable. Pour l'essentiel, ces publications reconnaissent les très graves défauts de la métallurgie extractive de l'aluminium à partir du minerai et aussi les mérites extraordinaires du recyclage de l'aluminium puisqu'il représente moins de 10% de la consommation d'énergie de la métallurgie extractive à partir du minerai (on verra que c'est aussi moins de 10% de la pollution et du capital). C'est précisément sur le recyclage que se fondent les campagnes de promotion de l'emballage boisson, en Suisse en particulier. Cependant, les données concernant le recyclage de l'aluminium publiées par l'industrie de l'aluminium reflètent seulement en partie ces mérites. Dans les années 1970, les taux de croissance de la production recyclée sont devenus plus élevés que ceux de la production électrolytique. Par contre, les taux de recyclage, établis à indicateur identique, sont unanimement tous médiocres comparativement à d'autres matériaux tels le cuivre et le fer. Composante de l'industrie de l'aluminium, le recyclage bénéficie d'une image favorable auprès du grand public, démontrant le succès des campagnes de communication. A l'inverse, à l'intérieur de l'industrie de l'aluminium, c'est une image dévalorisée. Les opinions émises par tous les acteurs, commerçants, techniciens, dirigeants, encore recueillies pendant ce travail, sont les suivantes : métier de chiffonnier, métier misérable, métier peu technique mais très difficile (un recycleur 15 d'aluminium n'a-t-il pas dit que son métier était un métier d'homme alors que celui du recycleur de cuivre était un jeu d'enfant). A notre avis ces opinions appartiennent à un passé révolu qu'elles retraduisent cependant fidèlement car le recyclage est aujourd'hui reconnu comme une contribution majeure au développement supportable de l'aluminium. C'est bien pour cette raison que, en 2000, l'industrie de l'aluminium mondiale a décidé d'abandonner le qualificatif « secondaire » jusque là utilisé pour désigner le métal recyclé. C'est en raison de toutes ces données discordantes et parfois contradictoires qu'a débuté ce travail encouragé par de nombreuses personnalités. Notre engagement a été incontestablement facilité par notre connaissance des savoirs indispensables (métallurgie, économie, statistiques) et surtout notre expérience acquise au cours d'une vie professionnelle menée à l'échelle mondiale dans (recherche et développement, production), pour (recherche, développement, marketing, stratégie) et autour (marketing, stratégie de produits connexes, les ferro-alliages, et concurrents, le fer) de l'industrie de l'aluminium. Notre objectif est de faire la vérité sur le recyclage de l'aluminium, un matériau qui a très largement contribué à faire le 20ème siècle, grâce à une revue critique embrassant tous les aspects de cette activité méconnue ; ainsi il n'y a pas d'histoire du recyclage de l'aluminium alors qu'il est plus que centenaire. Plus qu'une simple compilation, cette revue critique a été conduite comme une enquête scientifique, technique, économique, historique, socio-écologique faisant ressortir les faits principaux ayant marqué l'évolution du recyclage de l'aluminium. Elle conclut sur l'état réel du recyclage, qui se révèle globalement satisfaisant avec ses forces et ses faiblesses, et au-delà du recyclage sur l'adéquation de l'aluminium au développement supportable, adéquation largement insuffisante. C'est pourquoi, elle suggère les thèmes d'études intéressant tous ceux scientifiques, techniciens, historiens, économistes, juristes concernés par une industrie très représentative de notre monde en devenir, un monde où la place de l'aluminium dépendra de son aptitude à satisfaire les critères du développement supportable. ABSTRACT Owing to recycling, the aluminium industry's global energetic and environmental prints are much lower than its ore extractive metallurgy's ones. Likewise, recycling will allow the complete use of the expected avalanche of old scraps, consequently to the dramatic explosion of aluminium consumption since the 50's. The recycling state is characterized by: i) raw materials split in two groups :one, the new scrap, internal and prompt, proportional to semi-finished and finished products quantities, exhibits a fairly good and regular quality. The other, the old scrap, proportional to the finished products arrivïng at their end-of--life, about 22 years later on an average, exhibits a variable quality depending on the collect mode. ii) a poor recycling rate, near by that of steel. The aluminium industry generates too much new internal scrap and doesn't collect all the availa~e old scrap. About 50% of it is not recycled (when steel is recycling about 70% of the old scrap flow). iii) recycling techniques, all based on melting, are well handled in spite of aluminium atiiníty to oxygen and the practical impossibility to purify aluminium from any impurity. Sorting and first collect are critical issues before melting. iv) products and markets of recycled aluminium :New scraps have still been recycled in the production lines from where there are coming (closed loop). Old scraps, mainly those mixed, have been first recycled in different production lines (open loop) :steel deoxidation products followed during the 30's, with the development of the foundry alloys, by foundry pieces of which the main market is the automotive industry. During the 80's, the commercial development of the beverage can in North America has permitted the first old scrap recycling closed loop which is developing. v) an economy with low and erratic margins because the electrolytic aluminium quotation fixes scrap purchasing price and recycled aluminium selling price. vi) an industrial organisation historically based on the scrap group and the loop mode. New scrap is recycled either by the transformation industry itself or by the recycling industry, the remelter, old scrap by the refiner, the other component of the recycling industry. The big companies, the "majors" are often involved in the closed loop recycling and very seldom in the open loop one. To-day, aluminium industry's global energetic and environmental prints are too unbeara~ e and the sustainaЫe development criteria are not fully met. Critical issues for the aluminium industry are to better produce, to better consume and to better recycle in order to become a real sustainaЫe development industry. Specific issues to recycling are a very efficient recycling industry, a "sustainaЫe development" economy, a complete old scrap collect favouring the closed loop. Also, indirectly connected to the recycling, are a very efficient transformation industry generating much less new scrap and a finished products industry delivering only products fulfilling sustainaЫe development criteria.

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A luminescent bacterial biosensor was used to quantify bioavailable arsenic in artificial groundwater. Its light production above the background emission was proportional to the arsenite concentration in the toxicologically relevant range of 0 to 0.5 mu M. Effects of the inorganic solutes phosphate, Fe(II) and silicate on the biosensor signal were studied. Phosphate at a concentration of 0.25 g L-1 phosphate slightly stimulated the light emission, but much less than toxicologically relevant concentrations of the much stronger inducer arsenite. No effect of phosphate was oberved in the presence of arsenite. Freshly prepared sodium silicate solution at a concentration of 10 g L-1 Si reduced the arsenite-induced light production by roughly 37%, which can be explained by transient polymerization leading to sequestration of some arsenic. After three days of incubation, silicate did not have this effect anymore, probably because depolymerization occurred. In the presence of 0.4 g L-1 Fe(II), the arsenite-induced light emission was reduced by up to 90%, probably due to iron oxidation followed by arsenite adsorption on the less soluble Fe(III) possibly along with some oxidation to the stronger adsorbing As(V). Addition of 100 mu M EDTA was capable of releasing all arsenic from the precipitate and to transform it into the biologically measurable, dissolved state. The biosensor also proved valuable for monitoring the effectiveness of an arsenic removal procedure based on water filtration through a mixture of sand and iron granules.

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In most psychological tests and questionnaires, a test score is obtained bytaking the sum of the item scores. In virtually all cases where the test orquestionnaire contains multidimensional forced-choice items, this traditionalscoring method is also applied. We argue that the summation of scores obtained with multidimensional forced-choice items produces uninterpretabletest scores. Therefore, we propose three alternative scoring methods: a weakand a strict rank preserving scoring method, which both allow an ordinalinterpretation of test scores; and a ratio preserving scoring method, whichallows a proportional interpretation of test scores. Each proposed scoringmethod yields an index for each respondent indicating the degree to whichthe response pattern is inconsistent. Analysis of real data showed that withrespect to rank preservation, the weak and strict rank preserving methodresulted in lower inconsistency indices than the traditional scoring method;with respect to ratio preservation, the ratio preserving scoring method resulted in lower inconsistency indices than the traditional scoring method

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The preceding two editions of CoDaWork included talks on the possible considerationof densities as infinite compositions: Egozcue and D´ıaz-Barrero (2003) extended theEuclidean structure of the simplex to a Hilbert space structure of the set of densitieswithin a bounded interval, and van den Boogaart (2005) generalized this to the setof densities bounded by an arbitrary reference density. From the many variations ofthe Hilbert structures available, we work with three cases. For bounded variables, abasis derived from Legendre polynomials is used. For variables with a lower bound, westandardize them with respect to an exponential distribution and express their densitiesas coordinates in a basis derived from Laguerre polynomials. Finally, for unboundedvariables, a normal distribution is used as reference, and coordinates are obtained withrespect to a Hermite-polynomials-based basis.To get the coordinates, several approaches can be considered. A numerical accuracyproblem occurs if one estimates the coordinates directly by using discretized scalarproducts. Thus we propose to use a weighted linear regression approach, where all k-order polynomials are used as predictand variables and weights are proportional to thereference density. Finally, for the case of 2-order Hermite polinomials (normal reference)and 1-order Laguerre polinomials (exponential), one can also derive the coordinatesfrom their relationships to the classical mean and variance.Apart of these theoretical issues, this contribution focuses on the application of thistheory to two main problems in sedimentary geology: the comparison of several grainsize distributions, and the comparison among different rocks of the empirical distribution of a property measured on a batch of individual grains from the same rock orsediment, like their composition

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Background: To describe the overall and disease-free survival at five and ten years after breast cancer diagnosis in women from a previous case-control study, and establish related prognostic factors. Methods: We followed up 202 patients diagnosed between 1996 and 1998 in three public hospitals in Granada and Almeria provinces in Spain. Survival rates were calculated using the Kaplan and Meier method, and the Cox proportional hazards model was applied to identify the most significant variables contributing to survival. Results: Mean age at diagnosis was 54.27±10.4 years. Mean follow-up for overall survival was 119.91 months (95%CI 113.65126.17); the five-year survival rate was 83.9% (95%CI: 78.13-89.66) and the ten-year rate was 71% (95%CI: 63.25-78.74). Mean followup for disease-free survival was 118.75 months (95%CI 111.86125.65); the five-year disease-free survival rate was 81% (95%CI: 74.52-87.47) and the ten-year rate was 71.3% (95%CI: 63.33-79.26). The mortality rate of the study population was 33.17%. Conclusions: Disease characteristics are similar in our population to those in other Spanish and European regions, while the overall survival is higher than the mean rate during the same period in Europe (5-yr rate of 79%) and similar to that in Spain (83%).

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Aims: To evaluate whether ki-67 labelling index (LI) has independent prognostic value for survival of patients with bladder urothelial tumours graded according to the 2004 World Health Organisation classification. Methods: Ki-67 LI was evaluated in 164 cases using the grid counting method. Non-invasive (stage Ta) tumours were: papilloma (n = 5), papillary urothelial neoplasia of low malignant potential (PUNLMP; n = 26), and low (LG; n = 34) or high grade (HG; n = 15) papillary urothelial carcinoma. Early invasive (stage T1) tumours were: LG (n = 58) and HG (n = 26) carcinoma. Statistical analysis included Fisher and x2 tests, and mean comparisons by ANOVA and t test. Univariate and multivariate survival analyses were performed according to the Kaplan–Meier method with log rank test and Cox’s proportional hazard method. Results: Mean ki-67 LI increased from papilloma to PUNLMP, LG, and HG in stage Ta (p,0.0001) and from LG to HG in stage T1 (p = 0.013) tumours. High tumour proliferation (.13%) was related to greater tumour size (p = 0.036), recurrence (p = 0.036), progression (p = 0.035), survival (p = 0.054), and high p53 accumulation (p = 0.015). Ki-67 LI and tumour size were independent predictors of disease free survival (DFS), but only ki-67 LI was related to progression free survival (PFS). Cancer specific overall survival (OS) was related to ki-67 LI, tumour size, and p27kip1 downregulation. Ki-67 LI was the main independent predictor of DFS (p = 0.0005), PFS (p = 0.0162), and cancer specific OS (p = 00195). Conclusion: Tumour proliferation measured by Ki-67 LI is related to tumour recurrence, stage progression, and is an independent predictor of DFS, PFS, and cancer specific OS in TaT1 bladder urothelial cell carcinoma.

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A fish-infecting myxosporean, Henneguya hemiodopsis sp. n., found infecting the gills of Hemiodopsis microlepis and collected from the Poty River near the city of Teresina, Brazil, was described based on ultrastructural studies. The parasite occurred within large whitish polysporic plasmodia (up to 200 μm in diameter) containing asynchronous developmental sporogonic stages, mainly mature spores. The spores measured 19.7 ± 0.9 μm in total length (n = 30) and the ellipsoidal spore body was 10.8 ± 0.5 μm long, 3.3 ± 0.4 μm wide and 2.5 ± 0.5 μm thick. The spores were composed of two equal shell valves adhering together along the straight suture line, with each valve having equal-sized caudal tapering tails measuring 8.7 ± 0.6 μm in length. The spores were surrounded by a thin anastomosed network of microfibrils, more evident on the tails. There were two symmetric elongated bottle-like polar capsules 3.5 ± 0.3 μm long and 1.0 ± 0.2 μm wide, each with a polar filament with five to six coils. Given the morphological and ultrastructural differences from previously described parasites and the specificity of the host species, we propose a new species, named H. hemiodopsis sp. n.