977 resultados para Marginal Sealing
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La creación de una población mejorada de maíz, requiere al menos tres etapas: a) La conformación de una "población original" con variabilidad genética, b) La selección preliminar de plantas y/o progenies, y c) La "evaluación" en condiciones de campo de las mejores descendencias integradas en poblaciones experimentales. Precisamente, este proyecto está dirigido a la creación de variedades con estabilidad de rendimientos en las condiciones ambientales de la zona centro-norte de la Provincia de Córdoba, en donde el maíz es el único cereal que se cosecha y una de las mejores posibilidades como forrajera estival. Se ha inscripto el cv. "MPB-FCA 856", un maíz colorado duro creado para la producción de granos, que en marcado déficit hídrico produce rendimientos superiores a otros cultivares. Actualmente se dispone de una variedad sintética, próxima a ser inscripta como una nueva creación. Con orientación al desarrollo de otros cultivares, se plantean las líneas de trabajo que se enumeran seguidamente: Tema 1. Maíz Colorado Duro: Obtención de una variedad sintética. Se iniciará la caracterización varietal a fin de inscribir en el Instituto Nacional de Semillas el nuevo cv. sintético formado por 10 líneas S1, que presenta altos rendimientos de granos. Tema 2. Maíz Forrajero: Desarrollo de un cultivar con aptitud para ser utilizado como forraje en planta. En la zona marginal el pastoreo de lotes de maíz es común tanto en años con pocas precipitaciones pluviales como en ciclos favorables, por cuanto es una muy buena alternativa de forraje estival tanto en verdeo, silo o diferido. Se dispone de líneas propias con características de alto macollamiento y capacidad de rebrote; se plantea su mejoramiento por caracteres que hacen a la calidad forrajera, tales como porcentaje de materia seca, palatabilidad, fibra bruta, etc. Tema 3. Mejora en la eficiencia de selección para tolerancia a estrés hídrico en maíz ( Zea mays L.). Aportar evidencia experimental que mejore la eficiencia de la selección, cuando los genotipos se dispersarán en una gama de ambientes contrastantes por su disponibilidad hídrica. Se comenzará un esquema de selección recurrente en ambientes con diferente disponibilidad hídrica, empleando características que permitan identificar genotipos tolerantes. Paralelamente se implementarán metodologías de evaluación del germoplasma disponible mediante pruebas de laboratorio y campo, a fin de detectar fuentes de genes para tolerancia al estrés hídrico.
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Employment subsidies, wage subsidies, unemployment, displacement
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The objective of this study was to analyze the diet of fish species that use the mangrove vegetation for shelter and feeding in a river southeastern Brazil. The fieldwork, including collecting and underwater observations, was carried out in the dry (July and August 2004) and in the rainy season (February and March 2005) in order to assess the existence of seasonal variation in the diets. Seven kinds of food items were consumed, two of plant origin and five of animal origin. Crustaceans predominated in the diet of most species, either in the form of unidentified fragments or discriminated in eight groups. The predominance of species using mainly a single food source (crustaceans, principally Ostracoda and Tanaidacea) and the existence of seasonal variation in the diets of some species became very evident in the analysis food niche breadth, with a predominance of dietary specialists. In the Rio da Fazenda mangrove, the submersed marginal vegetation was used by the ichthyofauna as a locale for foraging, and principally as cover by bottom-feeding species. These species may be using the vegetation for protection from aerial and aquatic predators, or even from the pull of the current during the turn of the tide. In the study area, the great diversity of crustaceans constitutes an important food source for most fish species which adjusted their diet according to seasonal changes in food availability and to interactions with other species.
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It was made the characterization of marginal sphincter to the species Phymactis clematis (Drayton in Dana, 1849) and Aulactinia marplatensis (Zamponi, 1977), from intertidal ecosystem through their morphogical and functional study. The species P. clematis has a circumscript sphincter of palmate type. This muscle is constituted by a mesogloeal axis and several mesogloeal subaxes. Axis as well as subaxes give a support to the endoderm which border is smooth. Aulactinia marplatensis has a circunscript sphincter pinnate type. The axis has a truncated cone shape while in P. clematis the shape is cylindrical on its origin and it is bifurcated at the end. Both species experiments were carried out using the isolated muscles. They were stimulated at increasing KCl concentrations ranging from 20 to 200 mM. The results were analysed in the form of dose-response curves expressed in tension in grams force vs concentration. Contractil force increases in a sigmoid form to increasing KCl concentrations. The correlation between morphology and function and the differences shown in both species would be related to their intertidal distribution.
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Actual tax systems do not follow the normative recommendations of yhe theory of optimal taxation. There are two reasons for this. Firstly, the informational difficulties of knowing or estimating all relevant elasticities and parameters. Secondly, the political complexities that would arise if a new tax implementation would depart too much from current systems that are perceived as somewhat egalitarians. Hence an ex-novo overhaul of the tax system might just be non-viable. In contrast, a small marginal tax reform could be politically more palatable to accept and economically more simple to implement. The goal of this paper is to evaluate, as a step previous to any tax reform, the marginal welfare cost of the current tax system in Spain. We do this by using a computational general equilibrium model calibrated to a point-in-time micro database. The simulations results show that the Spanish tax system gives rise to a considerable marginal excess burden. Its order of magnitude is of about 0.50 money units for each additional money unit collected through taxes.
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Splenic marginal zone lymphoma (SMZL) is a low grade B-cell non-Hodgkin's lymphoma. The molecular pathology of this entity remains poorly understood. To characterise this lymphoma at the molecular level, we performed an integrated analysis of 1) genome wide genetic copy number alterations 2) gene expression profiles and 3) epigenetic DNA methylation profiles.We have previously shown that SMZL is characterised by recurrent alterations of chromosomes 7q, 6q, 3q, 9q and 18; however, gene resolution oligonucleotide array comparative genomic hybridisation did not reveal evidence of cryptic amplification or deletion in these regions. The most frequently lost 7q32 region contains a cluster of miRNAs. qRT-PCR revealed that three of these (miR-182/96/183) show underexpression in SMZL, and miR-182 is somatically mutated in >20% of cases of SMZL, as well as in >20% of cases of follicular lymphoma, and between 5-15% of cases of chronic lymphocytic leukaemia, MALT-lymphoma and hairy cell leukaemia. We conclude that miR-182 is a strong candidate novel tumour suppressor miRNA in lymphoma.The overall gene expression signature of SMZL was found to be strongly distinct fromthose of other lymphomas. Functional analysis of gene expression data revealed SMZL to be characterised by abnormalities in B-cell receptor signalling (especially through the CD19/21-PI3K/AKT pathway) and apoptotic pathways. In addition, genes involved in the response to viral infection appeared upregulated. SMZL shows a unique epigenetic profile, but analysis of differentially methylated genes showed few with methylation related transcriptional deregulation, suggesting that DNA methylation abnormalities are not a critical component of the SMZL malignant phenotype.
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Although it might have been expected that, by this point in time, the unacceptability of the marginal productivity theory of the return on capital would be universally agreed, that is evidently not the case. Popular textbooks still propound the dogma to the innocent. This note is presented in the hope that a succinct indication of the origins of the theory it will contribute to a more general appreciation of the unrealistic and illogical nature of this doctrine.
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We reformulate neoclassical consumer choice by focusing on lambda, the marginal utility of money. As the opportunity cost of current expenditure, lambda is approximated by the slope of the indirect utility function of the continuation. We argue that lambda can largely supplant the role of an arbitrary budget constraint in partial equilibrium analysis. The result is a better grounded, more flexible and more intuitive approach to consumer choice.
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The purpose of this note is to supplement the author’s earlier remarks on the unsatisfactory nature of the neoclassical account of how the return on capital is determined. (See Strathclyde Discussion Paper 12-03: “The Marginal Productivity Theory of the Price of Capital: An Historical Perspective on the Origins of the Codswallop”). The point is made via a simple illustration that certain matters which are problematical in neoclassical terms are perfectly straightforward when viewed from a classical perspective. Basically, the marginalist model of the nature of an economic system is not fit for purpose in that it fails to comprehend the essential features of a surplus-producing economic system as distinct from one merely of exchange.
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BACKGROUND: Dissection during laparoscopic surgery produces smoke containing potentially toxic substances. The aim of the present study was to analyze smoke samples produced during laparoscopic colon surgery using a bipolar vessel sealing device (LigaSuretrade mark). METHODS: Four consecutive patients undergoing left-sided colectomy were enrolled in this pilot study. Smoke was produced by the use of LigaSuretrade mark. Samples (5,5l) were evacuated from the pneumoperitoneum in a closed system into a reservoir. Analysis was performed with CO2-laser-based photoacoustic spectroscopy and confirmed by a Fourier-transform infrared spectrum. The detected spectra were compared to the available spectra of known toxins. RESULTS: Samples from four laparoscopic sigmoid resections were analyzed. No relevant differences were noted regarding patient and operation characteristics. The gas samples were stable over time proven by congruent control measurements as late as 24 h after sampling. The absorption spectra differed considerably between the patients. One broad absorption line at 100 ppm indicating H2O and several unknown molecules were detected. With a sensitivity of alpha min ca 10-5 cm-1 no known toxic substances like phenol or indole were identified. CONCLUSION: The use of a vessel sealing device during laparoscopic surgery does not produce known toxic substances in relevant quantity. Further studies are needed to identify unknown molecules and to analyze gas emission under various conditions.
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Résumé du document de thèse Quito, capitale andine de près de deux millions d'habitants, a vu se développer des quartiers ghettos réunissant une population en constante évolution. Mouvements migratoires mal connus, hétérogénéité ethnique et socioculturelle, accès limité aux services publics et conditions de vie difficiles jouent un rôle essentiel mais complexe dans la planification des services de santé. L'étude ciblée de cette problématique est un sérieux défi à relever car les mégalopoles latino-américaines connaissent une importante urbanisation avec pour corollaire une augmentation de la pauvreté urbaine. Les indicateurs de santé tels que mortalité infantile, espérance de vie ou incidence des maladies infectieuses montrent une amélioration globale qui ne reflète toutefois pas les importantes disparités caractéristiques du continent. La démarche exposée dans ce document est une réponse à la demande d'un appui médical par une communauté urbaine défavorisée, pour laquelle peu de données étaient disponibles. Une évaluation des conditions de vie et des besoins en soins a donc été effectuée par trois étudiants en médecine de Lausanne au moyen d'une enquête et d'ateliers qui ont permis de réunir les opinions des différents acteurs sociaux et sanitaires. Cette étude a pu identifier et mesurer les déterminants de santé, comprendre certaines dynamiques locales pour enfin cibler les principales lignes d'actions d'un centre de santé communautaire. Ce document décrit l'ensemble du processus conduit durant cinq ans et expose les données brutes ainsi que leur analyse ; il propose des recommandations concrètes pour une promotion de la santé adaptée aux besoins d'une communauté urbaine défavorisée d'Amérique du Sud. Son objectif est de fournir des données utilisables par les acteurs de santé locaux et de participer ainsi à la réflexion en cours sur la réforme du système de santé équatorien. Il comporte également une bibliographie, point de départ pour d'autres études sur le sujet. Le dossier, construit de manière chronologique, présente l'information de façon accessible et cohérente. Il se veut un témoignage utile, avec ses forces et ses faiblesses, à l'action locale sous forme d'une publication en espagnol qui sera distribuée aux différents acteurs sociaux et sanitaires concernés.
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OBJECTIVES: We examined the correlation between the quantitative margin analysis of two laboratory test methods (Berlin, Zurich) and the clinical outcome in Class V restorations. METHODS: Prospective clinical studies with an observation period of at least 18 months were searched in the literature, for which laboratory data were also available. The clinical outcome variables were retention loss, marginal discoloration, detectable margins and secondary caries. Forty-four clinical studies matched the inclusion criteria, including 34 adhesive systems for which laboratory data were also present. For both laboratory test methods and the clinical studies, an index was formulated to better compare the in vitro and in vivo results. Linear mixed models which included a random study effect were calculated. As most clinical data were available for 12 and 24 months, the main analysis was restricted to these recall intervals. RESULTS: The comparative analysis revealed a weak correlation between the clinical index and both in vitro indices. The correlation was statistically significant for the Berlin method but not for the Zurich method and only present if studies were compared which used the same composite in the in vitro and in vivo study. When defining specific cut-off values, the prognosis for the good clinical performance of an adhesive system based on in vitro results was 78% (Berlin) or 100% (Zurich). For poor performance it was 67% and 60%, respectively. No correlation was found between both in vitro methods. SIGNIFICANCE: The surrogate parameter "marginal adaptation" of restorations placed in extracted teeth has a mediocre value to predict the clinical performance of an adhesive system in cervical cavities. The composite is an important factor for a successful prediction. The comparison between in vitro/in vivo is sometimes hampered by the great variability of clinical results on the same adhesive system.
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B cells undergo a complex series of maturation and selection steps in the bone marrow and spleen during differentiation into mature immune effector cells. The tumor necrosis factor (TNF) family member B cell activating factor of the TNF family (BAFF) (BLyS/TALL-1) plays an important role in B cell homeostasis. BAFF and its close homologue a proliferation-inducing ligand (APRIL) have both been shown to interact with at least two receptors, B cell maturation antigen (BCMA) and transmembrane activator and cyclophilin ligand interactor (TACI), however their relative contribution in transducing BAFF signals in vivo remains unclear. To functionally inactivate both BAFF and APRIL, mice transgenic for a soluble form of TACI were generated. They display a developmental block of B cell maturation in the periphery, leading to a severe depletion of marginal zone and follicular B2 B cells, but not of peritoneal B1 B cells. In contrast, mice transgenic for a soluble form of BCMA, which binds APRIL, have no detectable B cell phenotype. This demonstrates a crucial role for BAFF in B cell maturation and strongly suggests that it signals via a BCMA-independent pathway and in an APRIL-dispensable way.