1000 resultados para Espaces De Fonctions Cp (x)


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Until recently, the hard X-ray, phase-sensitive imaging technique called grating interferometry was thought to provide information only in real space. However, by utilizing an alternative approach to data analysis we demonstrated that the angular resolved ultra-small angle X-ray scattering distribution can be retrieved from experimental data. Thus, reciprocal space information is accessible by grating interferometry in addition to real space. Naturally, the quality of the retrieved data strongly depends on the performance of the employed analysis procedure, which involves deconvolution of periodic and noisy data in this context. The aim of this article is to compare several deconvolution algorithms to retrieve the ultra-small angle X-ray scattering distribution in grating interferometry. We quantitatively compare the performance of three deconvolution procedures (i.e., Wiener, iterative Wiener and Lucy-Richardson) in case of realistically modeled, noisy and periodic input data. The simulations showed that the algorithm of Lucy-Richardson is the more reliable and more efficient as a function of the characteristics of the signals in the given context. The availability of a reliable data analysis procedure is essential for future developments in grating interferometry.

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A Ciência do Solo procura compreender e modelar os fenômenos ocorridos no solo, principalmente na zona não saturada. Como o entendimento de muitos desses fenômenos exige determinações em escalas que permitam incorporar aos modelos a variabilidade de poros e agregados, desenvolveu-se, na Embrapa Instrumentação Agropecuária, um tomógrafo de raios-X, de resolução micrométrica, com o objetivo de se obterem imagens, de forma não-destrutiva, de amostras de solo, com resolução espacial igual ou inferior a 100 μm. Foi possível projetar e construir um equipamento, de alta resolução, com baixo custo, comparativamente aos equipamentos comerciais disponíveis, cujos preços são proibitivos para aplicações em solo. Obtiveram-se imagens de amostras de solos com estrutura deformada, compostos por agregados de 212 a 250 μm, nos quais foram identificados poros medindo 100 μm ou menos. Poros dessas dimensões foram visualizados, também, em tomografias de amostras compostas de grãos de areia de 1 mm e capilares de vidro com diâmetros internos de 100, 200 e 300 μm. Tomografias de amostras não deformadas de solos evidenciaram, além de poros de 200 a 800 μm, partículas de alta densidade não-detectáveis com a tomografia de resolução milimétrica.

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Les élevages intensifs de porcs en espace fermé sont associés à une mauvaise qualité de l'air intérieur, aussi bien pour les éleveurs que pour les animaux. Plusieurs études épidémiologiques ont mis en évidence des associations entre cette mauvaise qualité de l'air et des symptômes aigus et chroniques, en particulier respiratoires au sein de la population d'éleveurs porcins. C'est pourquoi un grand nombre d'études se penche sur l'indentification des polluants inhalables en cause. En effet, si les polluants chimiques présents dans l'air des élevages porcins, tels que l'ammoniac ou les sulfures, sont bien connus, il reste à caractériser la nature des micro-organismes systématiquement présents dans ces environnements, ainsi qu'à mieux définir les facteurs qui infectent leur concentration dans l'air inhalable. Dans cette note, deux études ont été choisies pour illustrer le type de moisissures et bactéries auxquelles les éleveurs porcins sont exposés, et pour présenter les facteurs qui influencent les concentrations en bioaerosols dans ces environnements.

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Foram caracterizados fisico-quimicamente ácidos húmicos, obtidos de composto de resíduos sólidos urbanos (AH-CRSU) e de lodo de estação de tratamento de esgoto (AH-LETE), ambos produzidos na cidade do Rio de Janeiro, por meio da análise da composição elementar, acidez total, de dados espectroscópicos (UV-Vis; IV, RMN de 13C-CP/MAS) e microscopia eletrônica de varredura (MEV). A análise das características estruturais revelou diferenças entre os AHs estudados. A presença de sistemas aromáticos foi observada por meio da espectroscopia de UV-Vis, indicando sistemas mais substituídos nos AH-LETE. A espectroscopia na região do infravermelho (IV) mostrou a presença de estruturas alifáticas nos AHs e maior complexidade nos sinais de absorção devida a polissacarídeos nos AH-CRSU. Além disso, foram observados grupos OH, COOH, COO-, CO2NH2, e confirmada a presença de sistemas aromáticos. Com a análise de RMN de 13C-CP/MAS, foi possível verificar as diferenças quantitativas nos diferentes tipos de carbono. Os AH-LETE apresentaram maior quantidade de grupos aromáticos e de COOH. A análise de RMN de 13C-CP/MAS também mostrou presença de polissacarídeos, N em aminoácidos e grupamentos OCH3. O conjunto de propriedades avaliadas permitiu indicar que a fração ácidos húmicos dos resíduos é "do tipo" ou "análoga" aos ácidos húmicos de origem pedogênica.

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Ce travail porte sur l'étude des processus et fonctions psychiques de la création littéraire et de l'écriture dans une perspective psychanalytique, à partir d'une méthodologie de recherche qualitative exploratoire. Un premier volet de la recherche s'attache à étudier les processus et fonctions psychiques dans la création littéraire à partir de six entretiens semi-structurés avec des écrivains romands publiés. Les entretiens sont analysés en profondeur à partir de la méthodologie qualitative Interpretative Phenomenological Analysis (Smith, Flowers & Larkin, 2009). Un second volet de la recherche étudie les processus et fonctions psychiques de l'écriture dans un atelier de groupe à médiation écriture prenant place dans un Centre de Jour pour adultes, à partir de l'élaboration de deux cas. L'articulation des analyses de ces expériences d'écriture dans les deux contextes étudiés permet de mettre en évidence des enjeux de continuité/discontinuité dans le passage du premier mouvement créateur de l'écriture - le « miroir-papier » - vers le mouvement de la publication/lecture - le « miroir-lecteur ». Ces enjeux de partage invitent à penser le travail créateur de l'écriture à partir de la notion de « Moi- peau » (Anzieu, 1995) et à préciser cinq fonctions psychiques de l'écriture : transformation ; protection ; échange ; réassurance narcissique ; partage. Un accent particulier est porté sur la fonction de protection, dans la tension qu'elle entretient avec celle de transformation, au travers de la mise en évidence de six formes d'enveloppes d'écriture protectrice. Finalement, les analyses mettent en évidence la manière dont cette tension entre un investissement défensif de l'écriture et un investissement de transformation se déploie par des voies singulières en vue d'une tentative de résolution du conflit subjectif interne entre les exigences du « public intérieur » (De M'Uzan, 1964) et la rencontre avec l'objet réel. Ces pistes d'analyses permettent de préciser les modalités de contribution de l'écriture aux processus de symbolisation et d'enrichir la pratique du champ des médiations thérapeutiques de repères d'appréciation clinique. - Based on an exploratory qualitative research methodology, this work focuses on the psychical processes and functions of literary creation and writing from a psychoanalytic perspective. The first part of the research investigates psychical processes and functions in creative writing through the analysis of six semi-structured interviews with published Swiss writers. The interviews are analyzed according to the exploratory qualitative methodology Interpretative Phenomenological Analysis (Smith, Flowers & Larkin, 2009). The second area of research examines the processes of writing in the context of an art-therapy writing group that took place in an adult day center. The observations lead to the elaboration of two case studies. The joint analysis of these writing experiences highlights issues of continuity/discontinuity in passing from the first creative writing movement - the « mirror-paper » - to the final publication/reading of the work - the «mirror-reader». These issues enable us to understand the creative writing processes from the concept of the « skin-ego » (Anzieu, 1995). Five functions of writing are proposed: transformation, protection, exchange, narcissistic reassurance, and sharing. An emphasis on the tension between the protection and the transformation functions is highlighted through the identification of six forms of protective writing psychical envelopes. Finally, the analysis shows how this tension between a defensive and a transformative investment in writing takes place in an attempt to resolve the internal conflict between the « inner audience » (De M'Uzan, 1964) and the encounter with the real object. This study clarifies the way creative writing can contribute to symbolization and can enrich clinical assessment in the field of art-therapy.

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Risperidone is metabolized by polymorphic enzymes, and a large variability in plasma concentration and therapeutic response is observed. Risperidone long-acting injection (RLAI) avoids the first-pass effect, and little is known about the influence of gene polymorphisms involved in its pharmacokinetics. The influence on plasma concentrations of risperidone (RIS), its metabolite 9-hydroxy-risperidone, and on adverse effects were investigated for polymorphisms of cytochrome P450 2D6 (CYP2D6) (*3, *4, *5, *6), CYP3A (CYP3A4*1B, CYP3A4 rs4646437, CYP3A5*3, CYP3A7*1C), ABCB1 (1236C>T, 2677G>T, 3435C>T), NR1/2 coding for pregnane X receptor (rs1523130, rs2472677, rs7643645), and for CYP3A activity measured by a phenotyping test. Forty-two patients with at least 4 consecutive unchanged doses of RLAI were included in a multicenter cross-sectional study. A 55% lower dose-adjusted plasma levels of RIS were observed for CYP2D6 ultrarapid metabolizers (n = 5) as compared with CYP2D6 intermediate metabolizers (P < 0.007). NR1/2 polymorphism (rs7643645A>G) influenced RIS exposure with a 2.8-fold lower active moiety (P = 0.031) in GG compared with the AA genotype. This was confirmed in a second independent cohort (n = 16). Furthermore, high-density lipoprotein cholesterol was positively correlated with CYP3A activity (P = 0.01), and the NR1/2 (rs2472677) polymorphism was associated with different adverse effects including prolactin plasma levels adjusted for age and sex. In conclusion, our results confirmed the influence of CYP2D6 genotype on plasma levels of RIS. This is the first report on the influence of NR1/2 polymorphisms on RLAI exposure and on drug-induced adverse effects. These results should be validated in larger cohorts.