975 resultados para Lannoy, Ghillebert de, 1386-1462.


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Introduction: Interethnic admixture is a source of cryptic population structure that may lead to spurious genotype-phenotype associations in pharmacogenomic studies. We studied the impact of population stratification on the distribution of ABCB1 polymorphisms (1236C > T, 2677G > T/A and 3435C > T) among Brazilians, a highly admixed population with Amerindian, European and African ancestral roots. Methods: Individual DNA from 320 healthy adults was genotyped with a panel of ancestry informative markers, and the proportions of African component of ancestry (ACA) were estimated. ABCB1 genotypes were determined by the single base extension/termination method. We describe the association between ABCB1 polymorphisms and ACA by fitting a linear proportional odds logistic regression model to the data. Results: The distribution of the ABCB1 2677G > T/A and 3435C > T, but not the 1236C > T, SNPs displayed a significant trend for decreasing frequency of the T alleles and TT genotypes from White to Intermediate to Black individuals. The same trend was observed in the frequency of the T/nonG/T haplotype at the 1236, 2677 and 3435 loci. When the population sample was proportioned in quartiles, according to the individual ACA estimates, the frequency of the T allele and TT genotype at each locus declined progressively from the lowest (< 0.25 ACA) to the highest (> 0.75 ACA) quartile. Linear proportional odds logistic regression analysis confirmed that the odds of having the T allele at each locus decreases in a continuous manner with the increase of the ACA, throughout the ACA range (0.13-0.94) observed in the overall population sample. A significant association was also detected between the individual ACA estimates and the presence of the T/nonG/T haplotype in the overall population. Conclusion: Self-identification according to the racial/color categories proposed by the Brazilian Census is insufficient to properly control for population stratification in pharmacogenomic studies of ABCB1.

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The adsorption of the diazo dye Direct Red 23 onto a zinc oxide surface at 30 degrees C in the dark was investigated. The color reduction was monitored by spectrophotometry at 503 run. The FTIR and Raman spectra of the Direct Red 23 adsorption as a function of ZnO concentration were registered. From the PM3 semi-empirical calculations of the atomic charge density and dipole moment of the Direct Red 23 molecule, it was demonstrated that the azo, dye molecule may be adsorbed onto the ZnO Surface through molecule geometry modifications, enhancing the interfacial area causing a variation in the bonding frequencies. (C) 2009 Elsevier B.V. All rights reserved.

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In order to evaluate the interactions between Au/Cu atoms and clean Si(l 11) surface, we used synchrotron radiation grazing incidence X-ray fluorescence analysis and theoretical calculations. Optimized geometries and energies on different adsorption sites indicate that the binding energies at different adsorption sites are high, suggesting a strong interaction between metal atom and silicon surface. The Au atom showed higher interaction than Cu atom. The theoretical and experimental data showed good agreement. Crown Copyright (C) 2009 Published by Elsevier B.V. All rights reserved.

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We report the synthesis and spectroscopic/electrochemical properties of iron(II) complexes of polydentate Schiff bases generated from 2-acetylpyridine and 1,3-diaminopropane, acetylpyrazine and 1,3-diaminopropane, and from 2-acetylpyridine and L-histidine. The complexes exhibit bis(diimine)iron(II) chromophores in association with pyrazine, pyridine or imidazole groups displaying contrasting pi-acceptor properties. In spite of their open geometry, their properties are much closer to those of macrocyclic tetraimineiron(II) complexes. An electrochemical/spectroscopic correlation between E degrees(Fe(III/II)) and the energies of the lowest MLCT band has been observed, reflecting the stabilization of the HOMO levels as a consequence of the increasing backbonding effects in the series of compounds. Mossbauer data have also confirmed the similarities in their electronic structure, as deduced from the spectroscopic and theoretical data. (C) 2008 Elsevier B.V. All rights reserved.

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In the present work. the resonance Raman. UV-vis-NIR and scanning electron microscopic (SEM) data of nanorods (about similar to 300 rim in diameter) and nanofibers (about similar to 93 nm in diameter) of PANI are presented and compared. The PANI samples were synthesized in aqueous media with dodecybenzenesulfonic acid (DBSA) and beta-naphtalenesulfonic acid (beta-NSA) as dopants, respectively. The presence of hands at 578, 1400 and 1632cm(-1) in the Raman spectra of PANI-NSA and PANI-DBSA shows that the formation of cross-linking structures is a general feature of the PANI chains prepared in micellar media. It is proposed that these structures are responsible for the one-dimensional PANI morphology formation. In addition, the Raman band at 609cm(-1) of PANI fibers is correlated with the extended PANI chain coil formation. (C) 2008 Elsevier B.V. All rights reserved.

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A biomimetic sensor is proposed as a promising new analytical method for determination of captopril in different classes of samples. The sensor was prepared by modifying a carbon paste electrode with iron (II) phthalocyanine bis(pyridine) [FePe(dipy)] complex. Amperometric measurements in a batch analytical mode were first carried out in order to optimize the sensor response. An applied potential lower than 0.2 V vs Ag vertical bar AgCl in 0.1 mol L(-1) of TRIS buffer at pH 8.0 provided the best response, with a linear range of 2.5 x 10(-5) to 1.7 x 10(-4) mol L(-1). A detailed investigation of the selectivity of the sensor, employing seventeen other drugs, was also performed. Recovery studies were carried out using biological and environment samples in order to evaluate the sensor`s potential for use with these sample classes. Finally, the performance of the biomimetic sensor was optimized in a flow injection (FIA) system using a wall jet electrochemical cell. Under optimized flow conditions, a broad linear response range, from 5.0 x 10(-4) to 2.5 x 10(-2) mol L(-1), was obtained for captopril, with a sensitivity of 210 +/- 1 mu A L mol(-1).

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Examensarbetet är utfört på uppdrag av Banverket Data i Borlänge. Syftet med arbetet var att ta fram en kravspecifikation för en telefonkatalogs applikation för deras intranät samt utveckla denna i .Net mot ett befintligt mellanlager. Arbetet med utvecklingen har följt Banverket Datas egen metod för systemutveckling och arbetet med förstudierna har använt kvalitativ och kvantitativ metod. Dessutom beskriver rapporten även kravspecifikationer mer ingående.

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Syftet med denna uppsats har varit att studera om det finns något genusperspektiv i valda nedslag i gymnasieläroböcker i ämnet historia. De teoretiska utgångspunkterna och definitionerna har hämtats i Micael Nilssons rapport Historia ur ett genusperspektiv – En granskning av genusaspekterna i ämnet historia vid Linköpings universitet. Materialet har kategoriserats i tre olika perspektiv; kvinnohi-storiskt perspektiv, jämställdhetsperspektiv och genusperspektiv. Litteraturen har därefter place-rats i den så kallade genustrappan som i Nilsson version består av fem olika steg; genusmedveten, jämställdhetsmedveten, könsmedveten, könsomedveten eller könsmakts-förstärkande. Det un-dersökta materialet har bestått av fem läroböcker som behandlar A-kursen i historia. Läroböcker-na är utgivna på fem olika förlag, ingen av dem har en ensam författare och tre av böckerna har en kvinnlig medförfattare. Undersökningen är baserad på både den kvalitativa och den kvantitati-va metoden. Den kvantitativa delen av undersökning har gått ut på att räkna antal kvinnonamn i böckernas register och antal illustrationer som innehåller kvinnor. I den kvalitativa delen av un-dersökningen har material om kvinnor samt kvinnors situation i kapitlen om antikens Grekland, nordisk medeltid och industrialismen analyserats. Undersökningen visar att läroböckerna repre-senterar en historieskrivning som i stora drag lämnar kvinnorna utanför. Ingen av böckerna når upp till kategorien genusmedveten, de två böcker som placerar sig högst når kategorien jäm-ställdhetsmedveten. Resultatet visar att läroböckerna inte lever upp till styrdokumentens krav på en jämställd undervisning.

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Little is known about relationships between quality of care (QoC) and use of complementary and alternative medicine (CAM) among patients with lung cancer (LC). Purpose: This study examines CAM-use among patients with LC in Sweden, associations between QoC and CAM-use among these patients, and reported aspects of LC-care perceived as particularly positive and negative by patients, as well as suggestions for improving QoC. Methods: Survey data from 94 patient members of the Swedish LC patient organization about CAM-use and QoC as measured by the instrument “Quality from the patient’s perspective” were analyzed. Results: Fifty (53%) LC-patients used CAM, with 40 of the CAM-users reporting that CAM helped them. The most common CAMs used were dietary supplements and natural remedies, followed by prayer. Significantly more patients reported using prayer and meditation for cure than was the case for other types of CAM used. Less than half the CAM-users reported having spoken with staff from the biomedical health care system about their CAM-use. Patients provided numerous suggestions for improving LC-care in a variety of areas, aiming at a more effective and cohesive care trajectory. No differences in QoC were found between CAM-users and non-CAM-users, but differences in CAM-use i.e. type of CAM, reasons for using CAM, and CAM-provider consulted could be associated with different experiences of care. Conclusions: It is important to recognize that CAM-users are not a homogeneous group but might seek different types of CAMs and CAM-providers in different situations depending on experiences of care.

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A description of a data item's provenance can be provided in dierent forms, and which form is best depends on the intended use of that description. Because of this, dierent communities have made quite distinct underlying assumptions in their models for electronically representing provenance. Approaches deriving from the library and archiving communities emphasise agreed vocabulary by which resources can be described and, in particular, assert their attribution (who created the resource, who modied it, where it was stored etc.) The primary purpose here is to provide intuitive metadata by which users can search for and index resources. In comparison, models for representing the results of scientific workflows have been developed with the assumption that each event or piece of intermediary data in a process' execution can and should be documented, to give a full account of the experiment undertaken. These occurrences are connected together by stating where one derived from, triggered, or otherwise caused another, and so form a causal graph. Mapping between the two approaches would be benecial in integrating systems and exploiting the strengths of each. In this paper, we specify such a mapping between Dublin Core and the Open Provenance Model. We further explain the technical issues to overcome and the rationale behind the approach, to allow the same method to apply in mapping similar schemes.

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O objetivo deste trabalho é desenvolver um modelo computacional, baseado no método dos elementos finitos, para o estudo de peças de concreto armado e protendido submetidas a estados planos de tensão. O estudo abrange situações de carga de curta e longa duração, onde consideram-se fluência e retração do concreto e relaxação do aço. São utilizados modelos constitutivos elasto-viscoplásticos para descrever o comportamento dos materiais. Implementou-se um modelo de camadas superpostas para melhor representar o comportamento do concreto, onde o material é composto de diversas camadas que sofrem a mesma deformação. Cada camada possui diferentes características materiais e a tensão total é obtida pela soma das diferentes contribuições de cada camada. Para a fissuração da concreto, utilizou-se um modelo de fissuras distribuídas, que leva em conta a contribuição do concreto entre fissuras. Tanto a amadura passiva como a de pratensão são introduzidas no modelo como uma linha de material mais rígido dentro do elemento de concreto. Os deslocamentos ao longo da armadura são referenciados aos deslocamentos nodais do elemento de concreto. Deste modo, obtém-se uma matriz de rigidez para a armadura com as mesmas dimensões que a matriz de rigidez do elemento de concreto, A matriz de rigidez do elemento concreto-aço é a soma das duas matrizes. Considera-se aderência perfeita entre o concreto e o aço. Os resultados obtidos com esse programa computacionai são comparados com valores experimentais disponíveis.

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Atualmente os sistemas computacionais mais sofisticados são aqueles que apresentam imagens gráficas. Devido às características de alta velocidade de processamento e excelente resultado na geração de imagens o uso da Computação Gráfica se dá em diversas áreas como a indústria, pesquisa, publicidade, entretenimento, medicina, treinamento, dentre outras. Este trabalho aborda dois assuntos clássicos na Computação Gráfica, Geometria Sólida Construtiva (CSG) e Sombras Projetadas. Ambos são muito importantes para esta linha de pesquisa da Ciência da Computação. A Geometria Sólida Construtiva é utilizada na modelagem de objetos e as sombras projetadas são necessárias para aumentar o realismo das imagens. Geometria sólida construtiva (CSG) é uma técnica para a modelagem de sólidos, que define sólidos complexos pela composição de sólidos simples (primitivas). Isso inclui também a composição de objetos já combinados, até que se chegue a um objeto mais complexo. Um fator muito importante e necessário na obtenção de imagens realistas e que deve ser considerado é a utilização de sombras, pois estas são eficazes no realismo e impressão espacial de objetos tridimensionais. As sombras estabelecem diversos níveis de profundidade na imagem, fazem uma pontuação geométrica na cena de modo a evitar que os objetos não pareçam estar flutuando no ar. Este trabalho consiste em apresentar uma proposta para a geração de sombras em objetos modelados pela Geometria Sólida Construtiva. Para tanto foram estudados os assuntos referentes à modelagem de objetos por CSG, algoritmos para a geração de sombras “bem delimitadas” e formas de gerar sombras na Geometria Sólida Construtiva. O processo de geração de sombras em cenas modeladas por CSG, através da aplicação das mesmas operações booleanas envolvidas na modelagem dos objetos, sobre as sombras nem sempre apresenta resultados corretos. Diante disso, foram investigadas outras formas de solucionar o problema. Dentre estas, uma alternativa é a realização de transformações na árvore binária CSG, através de outras operações, envolvendo o uso de complemento com operações de união e interseção, para a modelagem do objeto e geração da sombra correspondente. Com base nos estudos realizados foram implementados dois protótipos que exibem a sombra projetada de objetos modelados por CSG. Na implementação do protótipo A utilizaram-se as técnicas tradicionais de modelagem de sólidos e sombra projetada. Os resultados obtidos com este protótipo serviram de referência. No protótipo B os resultados foram obtidos através da aplicação da zona ativa das primitivas na modelagem dos objetos e a sombra é projetada durante o processo de avaliação de contornos do sólido. Os resultados obtidos com este protótipo são comparados com os resultados do protótipo A e são apresentados como forma de exibir a aplicação do método proposto.