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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Estudo do gene MAP3K1 em pacientes portadores de distúrbios do desenvolvimento sexual 46,XY por anormalidades no desenvolvimento gonadal / Study of the MAP3K1 gene in patients with disorders of sexual development 46,XY by abnormalities in gonadal development

Machado, Aline Zamboni 20 February 2017 (has links)
Introdução: Pearlman e colaboradores relacionou a presença de mutações ativadoras no gene MAP3K1 com o desenvolvimento testicular anormal em pacientes com disgenesia gonadal 46,XY familial, embora os estudos em camundongos tenham demonstrado que o gene Map3k1 não é essencial para a determinação testicular. No desenvolvimento gonadal masculino, a ligação do MAP3K1 à proteína RHOA promove uma fosforilação normal de p38 e ERK1/2, o que determina um bloqueio da via da beta-catenina pela MAP3K4. Já no desenvolvimento feminino, ocorre uma hiper fosforilação de p38 e ERK1/2, o que determina a ativação da via da beta-catenina e o bloqueio da via de retroalimentação positiva do SOX9 e o desenvolvimento testicular. Objetivos: Pesquisar a presença de variantes alélicas do gene MAP3K1 em pacientes portadores de distúrbios do desenvolvimento sexual (1) 46,XY por anormalidades do desenvolvimento gonadal e avaliar a repercussão funcional das variantes identificadas. Casuística e Métodos: Quarenta e sete pacientes com disgenesia gonadal 46,XY (17 com a forma completa e 29 com a forma parcial) e uma paciente com DDS 46,XY de causa etiológica não conhecida foram estudados. As regiões codificadoras do gene MAP3K1 foram amplificadas e sequenciadas pelo método de Sanger ou painel customizado de genes-alvo associados ao DDS. Estudo in vitro utilizando o método de detecção colorimétrica In-Cell ELISA com anticorpos específicos para detecção de ERK1/2 e AKT, fosforilado e não fosforilado foi realizado em fibroblastos obtidos por biópsia de pele e mantidos em cultura celular de 3 indivíduos portadores de variantes no MAP3K1. A quantificação da fosforilação de p38 e ERK por ensaio de citometria em células linfoblastóides mutadas foram realizados em amostras de 4 indivíduos portadores de variantes no MAP3K1 em estudo realizado em colaboração. Imunohistoquímica com anticorpos anti Caspase-3 foram realizadas em tecidos gonadais parafinados das pacientes portadoras de variantes alélicas nos genes MAP3K1 e FGFR2. Resultados: Vinte e uma variantes alélicas, sete das quais ainda não descritas na literatura, foram identificadas no gene MAP3K1. Quatro novas variantes alélicas exônicas e não sinônimas (p.Leu639Pro, p.Leu447Trp, p.Thr657Arg e p.Cys691Arg) foram identificadas em heterozigose; todas foram classificadas como deletérias para a proteína nos estudos de predição \"in silico\", não foram identificadas em indivíduos controles brasileiros estudados e não estão descritas nos bancos de dados populacionais. A variante p.Leu639Pro foi identificada em duas irmãs com disgenesia gonadal 46,XY portadoras da variante p.Ser453Leu no gene FGFR2 identificada previamente. A variante intrônica c.834+1G >T identificada em heterozigose foi classificada como deletéria à proteína na análise no site de predição para alteração de \"splicing\". Os ensaios colorimétricos para detecção de ERK1/2 e AKT, fosforilado e não fosforilado foram inconclusivos. Os estudos in vitro de avaliação dos níveis de fosforilação de p38 e ERK evidenciaram uma maior fosforilação nas culturas celulares mutantes para o MAP3K1 quando comparado com a linhagem celular selvagem, resultado estatisticamente significativo ( p < 0,001) e que corrobora com os dados publicados previamente. A imunohistoquímica com anticorpos anti Caspase-3 mostrou uma maior marcação em células germinativas nos tecidos gonadais das pacientes portadoras das variantes no MAP3K1 e FGFR2 do que no tecido testicular normal, porém marcações foram identificadas também em células germinativas de tecidos testiculares de indivíduos com DDS 46,XY de outras etiologias. Conclusões: Os achados sugerem fortemente a participação das mutações identificadas no MAP3K1 na etiologia dos distúrbios do desenvolvimento sexual dos pacientes estudados. Porém, uma melhor compreensão dos mecanismos de participação da via MAPK nas redes gênicas de regulação do processo de determinação testicular humano ainda é necessário / Introduction: Pearlman et al. associated the presence of activating mutations in MAP3K1 gene with abnormal testicular development in patients with familial 46,XY gonadal dysgenesis, although studies in mice have shown that the Map3k1 gene is not essential for testicular determination. In male gonadal development, the binding of MAP3K1 to the RHOA protein promotes a normal phosphorylation of p38 and ERK1/2, and a blockade of the beta- catenin pathway is determined by MAP3K4. In the female development, hyperphosphorylation of p38 and ERK1/2 occurs. p38 and ERK1/2 hyperphosphorylated determine the activation of the beta-catenin pathway, the blockade of the positive feedback pathway of SOX9 and the testicular development. Objectives: To investigate the presence of allelic variants of the MAP3K1 gene in patients with 46,XY disorders of sex development (DSD) due to abnormalities of gonadal development and to evaluate the functional repercussion of the identified variants. Patients and Methods: Forty-seven patients with 46,XY gonadal dysgenesis (17 patients with complete form and 29 with partial form) and one patient with 46,XY DSD of unknown cause were studied. The MAP3K1 coding regions were amplified and sequenced by Sanger method or by custom panel of target genes associated with DSD. In-Cell ELISA assay with specific antibodies for the detection of phosphorylated and non-phosphorylated ERK1/2 and AKT was performed on fibroblasts obtained by skin biopsy and kept in cell culture of 3 individuals with MAP3K1 variants. Quantification of p38 and ERK phosphorylation by cytometric assay on mutated lymphoblastoid cells were performed on samples from 4 subjects with MAP3K1 variants in a collaborative study. Immunohistochemistry with anti-Caspase-3 antibodies were performed on paraffinembedded gonadal tissues of patients with MAP3K1 and FGFR2 allelic variants. Results: Twenty-one allelic variants, seven of them have not yet been described in the literature, were identified in the MAP3K1. Four novel exonic and non-synonymous allelic variants (p.Leu639Pro, p.Leu447Trp, p.Thr657Arg and p.Cys691Arg) were identified in heterozygous state; all of them were classified as deleterious in silico prediction sites; they were not identified in Brazilian control subjects and they were not described in the human genetic variation databases. The p.Leu639Pro variant was identified in two sisters with 46,XY gonadal dysgenesis carrying the previously identified FGFR2 variant (p Ser453Leu). The intronic c.834+1G > T variant identified in heterozygous state was classified as deleterious in the prediction sites. Colorimetric assays for the detection of phosphorylated and nonphosphorylated ERK1/2 and AKT were not significant. In vitro studies to evaluate p38 and ERK phosphorylation levels evidenced increased phosphorylation in the MAP3K1 mutant cells when compared to the wild type cells line; a statistically significant result (p < 0.001) that confirmed previously published data. The immunohistochemistry study with anti-Caspase-3 antibodies showed that the gonadal tissues of patients with MAP3K1 and FGFR2 variants exhibited more apoptotic germ ceIls than normal testicular tissue, but stained germ cells were also identified in the testicular tissues of the 46,XY DSD controls.Conclusions: These findings strongly suggest the participation of MAP3K1 mutations in the etiology of the testicular abnormalities of the 46,XY DSD patients of this study. However, a better understanding of the mechanisms of MAPK pathway in the gene regulatory networks of the human testicular determination process is still necessary
52

Estudo do gene MAP3K1 em pacientes portadores de distúrbios do desenvolvimento sexual 46,XY por anormalidades no desenvolvimento gonadal / Study of the MAP3K1 gene in patients with disorders of sexual development 46,XY by abnormalities in gonadal development

Aline Zamboni Machado 20 February 2017 (has links)
Introdução: Pearlman e colaboradores relacionou a presença de mutações ativadoras no gene MAP3K1 com o desenvolvimento testicular anormal em pacientes com disgenesia gonadal 46,XY familial, embora os estudos em camundongos tenham demonstrado que o gene Map3k1 não é essencial para a determinação testicular. No desenvolvimento gonadal masculino, a ligação do MAP3K1 à proteína RHOA promove uma fosforilação normal de p38 e ERK1/2, o que determina um bloqueio da via da beta-catenina pela MAP3K4. Já no desenvolvimento feminino, ocorre uma hiper fosforilação de p38 e ERK1/2, o que determina a ativação da via da beta-catenina e o bloqueio da via de retroalimentação positiva do SOX9 e o desenvolvimento testicular. Objetivos: Pesquisar a presença de variantes alélicas do gene MAP3K1 em pacientes portadores de distúrbios do desenvolvimento sexual (1) 46,XY por anormalidades do desenvolvimento gonadal e avaliar a repercussão funcional das variantes identificadas. Casuística e Métodos: Quarenta e sete pacientes com disgenesia gonadal 46,XY (17 com a forma completa e 29 com a forma parcial) e uma paciente com DDS 46,XY de causa etiológica não conhecida foram estudados. As regiões codificadoras do gene MAP3K1 foram amplificadas e sequenciadas pelo método de Sanger ou painel customizado de genes-alvo associados ao DDS. Estudo in vitro utilizando o método de detecção colorimétrica In-Cell ELISA com anticorpos específicos para detecção de ERK1/2 e AKT, fosforilado e não fosforilado foi realizado em fibroblastos obtidos por biópsia de pele e mantidos em cultura celular de 3 indivíduos portadores de variantes no MAP3K1. A quantificação da fosforilação de p38 e ERK por ensaio de citometria em células linfoblastóides mutadas foram realizados em amostras de 4 indivíduos portadores de variantes no MAP3K1 em estudo realizado em colaboração. Imunohistoquímica com anticorpos anti Caspase-3 foram realizadas em tecidos gonadais parafinados das pacientes portadoras de variantes alélicas nos genes MAP3K1 e FGFR2. Resultados: Vinte e uma variantes alélicas, sete das quais ainda não descritas na literatura, foram identificadas no gene MAP3K1. Quatro novas variantes alélicas exônicas e não sinônimas (p.Leu639Pro, p.Leu447Trp, p.Thr657Arg e p.Cys691Arg) foram identificadas em heterozigose; todas foram classificadas como deletérias para a proteína nos estudos de predição \"in silico\", não foram identificadas em indivíduos controles brasileiros estudados e não estão descritas nos bancos de dados populacionais. A variante p.Leu639Pro foi identificada em duas irmãs com disgenesia gonadal 46,XY portadoras da variante p.Ser453Leu no gene FGFR2 identificada previamente. A variante intrônica c.834+1G >T identificada em heterozigose foi classificada como deletéria à proteína na análise no site de predição para alteração de \"splicing\". Os ensaios colorimétricos para detecção de ERK1/2 e AKT, fosforilado e não fosforilado foram inconclusivos. Os estudos in vitro de avaliação dos níveis de fosforilação de p38 e ERK evidenciaram uma maior fosforilação nas culturas celulares mutantes para o MAP3K1 quando comparado com a linhagem celular selvagem, resultado estatisticamente significativo ( p < 0,001) e que corrobora com os dados publicados previamente. A imunohistoquímica com anticorpos anti Caspase-3 mostrou uma maior marcação em células germinativas nos tecidos gonadais das pacientes portadoras das variantes no MAP3K1 e FGFR2 do que no tecido testicular normal, porém marcações foram identificadas também em células germinativas de tecidos testiculares de indivíduos com DDS 46,XY de outras etiologias. Conclusões: Os achados sugerem fortemente a participação das mutações identificadas no MAP3K1 na etiologia dos distúrbios do desenvolvimento sexual dos pacientes estudados. Porém, uma melhor compreensão dos mecanismos de participação da via MAPK nas redes gênicas de regulação do processo de determinação testicular humano ainda é necessário / Introduction: Pearlman et al. associated the presence of activating mutations in MAP3K1 gene with abnormal testicular development in patients with familial 46,XY gonadal dysgenesis, although studies in mice have shown that the Map3k1 gene is not essential for testicular determination. In male gonadal development, the binding of MAP3K1 to the RHOA protein promotes a normal phosphorylation of p38 and ERK1/2, and a blockade of the beta- catenin pathway is determined by MAP3K4. In the female development, hyperphosphorylation of p38 and ERK1/2 occurs. p38 and ERK1/2 hyperphosphorylated determine the activation of the beta-catenin pathway, the blockade of the positive feedback pathway of SOX9 and the testicular development. Objectives: To investigate the presence of allelic variants of the MAP3K1 gene in patients with 46,XY disorders of sex development (DSD) due to abnormalities of gonadal development and to evaluate the functional repercussion of the identified variants. Patients and Methods: Forty-seven patients with 46,XY gonadal dysgenesis (17 patients with complete form and 29 with partial form) and one patient with 46,XY DSD of unknown cause were studied. The MAP3K1 coding regions were amplified and sequenced by Sanger method or by custom panel of target genes associated with DSD. In-Cell ELISA assay with specific antibodies for the detection of phosphorylated and non-phosphorylated ERK1/2 and AKT was performed on fibroblasts obtained by skin biopsy and kept in cell culture of 3 individuals with MAP3K1 variants. Quantification of p38 and ERK phosphorylation by cytometric assay on mutated lymphoblastoid cells were performed on samples from 4 subjects with MAP3K1 variants in a collaborative study. Immunohistochemistry with anti-Caspase-3 antibodies were performed on paraffinembedded gonadal tissues of patients with MAP3K1 and FGFR2 allelic variants. Results: Twenty-one allelic variants, seven of them have not yet been described in the literature, were identified in the MAP3K1. Four novel exonic and non-synonymous allelic variants (p.Leu639Pro, p.Leu447Trp, p.Thr657Arg and p.Cys691Arg) were identified in heterozygous state; all of them were classified as deleterious in silico prediction sites; they were not identified in Brazilian control subjects and they were not described in the human genetic variation databases. The p.Leu639Pro variant was identified in two sisters with 46,XY gonadal dysgenesis carrying the previously identified FGFR2 variant (p Ser453Leu). The intronic c.834+1G > T variant identified in heterozygous state was classified as deleterious in the prediction sites. Colorimetric assays for the detection of phosphorylated and nonphosphorylated ERK1/2 and AKT were not significant. In vitro studies to evaluate p38 and ERK phosphorylation levels evidenced increased phosphorylation in the MAP3K1 mutant cells when compared to the wild type cells line; a statistically significant result (p < 0.001) that confirmed previously published data. The immunohistochemistry study with anti-Caspase-3 antibodies showed that the gonadal tissues of patients with MAP3K1 and FGFR2 variants exhibited more apoptotic germ ceIls than normal testicular tissue, but stained germ cells were also identified in the testicular tissues of the 46,XY DSD controls.Conclusions: These findings strongly suggest the participation of MAP3K1 mutations in the etiology of the testicular abnormalities of the 46,XY DSD patients of this study. However, a better understanding of the mechanisms of MAPK pathway in the gene regulatory networks of the human testicular determination process is still necessary
53

Phénomènes émergents et topologiques dans les systèmes BKT sur réseau / Topological and Emergent Phenomena in Lattice BKT Systems

Faulkner, Michael 16 March 2015 (has links)
Cette thèse s'intéresse aux phénomènes électrostatiques émergents dans les modèles magnétiques toroïdaux bi-dimensionnels à symétrie XY, fournissant ainsi un support pour de plus amples recherches dans le domaine de la transition de phase Berezinskii-Kosterlitz-Thouless (BKT).Dans de nombreux systèmes bi-dimensionnels, dont le modèle bi-dimensionnel XY du magnétisme, la transition BKT contrôle la dissociation thermique de paires de défauts topologiques liés. Le modèle XY est analogue au gaz de Coulomb bi-dimensionnel, à ceci près qu'il peut être simulé sans avoir à modéliser les interactions à longue distance du système Coulombien. Cette thèse élucide ce paradoxe en démontrant que l'approximation de Villain appliquée au modèle XY est strictement équivalente au modèle électrostatique de Maggs-Rossetto (MR) appliqué au système Coulombien bi-dimensionnel.Cette équivalence est utilisée pour sonder la transition BKT par l'application de l'algorithme MR au gaz de Coulomb bi-dimensionel. En simulant le système Coulombien, il est prouvé que les fluctuations dans l'organisation des charges autour du tore sont activées à la température de transition BKT. Ces fluctuations du champ électrique indiquent ainsi la phase de haute température de la transition.Il est ensuite montré que l'exposant critique effectif de la théorie de Bramwell-Holdsworth (BH) peut être mesuré dans les films d'hélium 4 superfluide, qui correspondent à des gaz de Coulomb effectifs dans la limite de systèmes de grandes tailles finies. / This thesis addresses the emergent electrostatics of two-dimensional, toroidal magnetic models that possess XY symmetry, providing a platform for novel investigations into the Berezinskii-Kosterlitz-Thouless (BKT) phase transition.The BKT transition drives the thermal dissociation of bound pairs of topological defects in many two-dimensional systems, including the two-dimensional XY model of magnetism. The XY model is closely analogous to the two-dimensional Coulomb gas, but can be simulated without computing the long-range interactions of the Coulombic system. This thesis elucidates this paradox by showing that Villain's approximation to the XY model is strictly equivalent to the Maggs-Rossetto (MR) electrostatic model when applied to the two-dimensional Coulomb gas.The mapping is used to probe the BKT transition through the application of the MR algorithm to the two-dimensional Coulomb gas. By simulating the Coulombic system, fluctuations in the winding of charges around the torus are shown to turn on at the BKT transition temperature. These topological-sector fluctuations in the electric field therefore signal the high-temperature phase of the transition.It is then shown that the effective critical exponent of Bramwell-Holdsworth (BH) theory can be measured in superfluid 4He films, which correspond to effective Coulomb gases in the limit of large but finite system size. With the Coulombic system taken as the base BKT system, it is inferred that BH theory is a general property of BKT systems.
54

Aspectos comportamentais e do desenvolvimento psicossexual dos pacientes com distúrbios do desenvolvimento sexual 46,XY na idade adulta / Behavioral and psychosexual aspects of 46,XY DSD individuals at adulthood

Batista, Rafael Loch 12 December 2017 (has links)
Introdução: O desenvolvimento psicossexual humano inicia no período pré-natal e é composto pelo papel de gênero (PG), pela identidade de gênero (IG) e pela orientação sexual (OS). Em indivíduos com DDS 46,XY, vários fatores podem comprometer esse desenvolvimento, levando a incongruência de identidade de gênero e à mudança de gênero. Nesses pacientes, a exposição androgênica pré-natal e o grau de virilização da genitália externa tem sido avaliados como possíveis influenciadores destes desfechos, mas seu papel ainda não foi esclarecido. Objetivos: Avaliar os desfechos psicossexuais - IG, PG e OS - e aspectos da vida sexual em uma coorte de indivíduos com DDS 46,XY na idade adulta com diagnostico etiológico caracterizado do ponto de vista clínico e molecular e investigar a influência da exposição androgênica pré-natal e do grau de virilização da genitália externa nesses desfechos e na prevalência de disforia de gênero (DG). Pacientes: 144 pacientes com diagnóstico etiológico confirmado de DDS 46,XY acompanhados do HCFMUSP com idade entre 16 e 60 anos foram incluídos neste estudo. Métodos: Os componentes do desenvolvimento psicossexual (IG, PG, OS) foram avaliados usando questionários e por teste psicológico projetivo (HTP - House-Tree-Person). O escore de Sinnecker foi utilizado para a mensuração do grau de virilização da genitália externa. A exposição androgênica pré-natal foi estimada de acordo com a etiologia do DDS 46,XY. Aspectos da vida sexual foram avaliados através de questionário específico.Todas as variáveis categóricas foram analisadas usando teste X². A força de associação foi avaliada pelo cálculo do V de Cramer. O índice kappa foi usado para avaliar concordância entre resultados dos testes. Resultados: Houve uma associação positiva entre exposição androgênica pré-natal e a maior incidência de desfechos psicossexuais masculinos em indivíduos com maior exposição. O grau de virilização da genitália externa não interferiu nos desfechos psicossexuais. Houve uma prevalência de 19% (27/144) de disforia de gênero em toda a coorte. Em 93% (25/27), a DG foi do sexo feminino para o masculino e ocorreu em 50% (16/32) de casos de deficiência de 5alfa-RD2, seguido de 33% (5/15) dos casos de deficiência da 17beta-HSD3 e se associou com exposição androgênica pré-natal (p < 001; V=0,461), mas não com a virilização da genitália externa. A mediana de idade do desejo de mudar de sexo foi de 8 anos (5 - 9) enquanto que a da idade da mudança de sexo foi 15 anos (10.5 - 20). Os desfechos psicossexuais mostraram maior concordância com o sexo social final (PG - k=0.81; IG - k=0.65 e OS - k=0.85) do que com o sexo de registro (PG - k=0.1; IG - k=0.25 e OS - k=0.15). Quanto a sexualidade, alguns parâmetros (fantasias sexuais, masturbação e parceiro sexual fixo) foram melhores no sexo masculino comparado ao feminino. No entanto, não houveram diferenças em relação aos parâmetros da vida sexual comparando indivíduos do sexo feminino com e sem atipia genital e indivíduos do sexo masculino que mantiveram o sexo social com os que mudaram para este sexo. Conclusões: A exposição androgênica pré-natal influenciou o desenvolvimento psicossexual em indivíduos com DDS 46,XY, de uma forma exposição-dependente, favorecendo desfechos masculinos, enquanto que o grau de virilização da genitália externa não influenciou estes desfechos. A DG do feminino para o masculino foi comum entre esses indivíduos e também foi influenciada pela exposição androgênica pré-natal. Os parâmetros psicossexuais nesses pacientes concorda muito mais com o sexo social final do que com o sexo de registro. A sexualidade dos indivíduos do sexo masculino tem aspectos mais satisfatórios que o feminino. Atipia genital no sexo feminino não afetou a sexualidade destas pacientes assim a sexualidade dos indivíduos que mudaram para o sexo masculino são semelhantes aos que foram registrados no sexo masculino Behavioral and Psychosexual Aspects of 46,XY DSD Individuals At Adulthood / Introduction: The human psychosexual development begins at prenatal period and is composed by gender role, gender identity and sexual orientation. In 46,XY DSD individuals a variety of factors may jeopardize an adequate psychosexual development and sometimes results in desire to change the gender. The effects of prenatal androgen exposure and the impact of atypical genitalia in the psychosexual outcomes have been suggested as influencing factors in the human psychosexual development but there is not conclusive evidence, especially in DDS 46, XY. Methods: We evaluated the psychosexual compounds - gender role (GR) at childhood gender identity (GI) and sexual orientation (SO) in individuals a large cohort of 144 46,XY DSD individuals, 86% of them raised in the female social sex, from a single tertiary medical center. The same psychologist, specialized in DSD, performed the psychosexual evaluation. We used a questionnaire and a projective psychological test (HTP test) to measure the psychosexual compounds. Prenatal androgen exposure was estimated considering the 46,XY etiology. Sinnecker\'s score was used to measure the external genitalia virilization. All ordinal variables were analyzed using Wilcoxon test. Categorical variables were analyzed using X2 test with posterior Cramer\'s V to measure the association strength. The kappa index was calculated as a concordance measure. Results: We found an association between prenatal androgen exposure and major prevalence of male psychosexual outcomes and a higher incidence of female to male gender dysphoria. There was not difference in the psychosexual outcomes according by external genitalia virilization in male and in female individuals. There was an incidence of 19% of gender dysphoria (27 out from 144). In 93% (n=25), the gender change was from female to male (F to M). The ethological diagnosis related with F to M GD were 5alpha-RD2 deficiency (5ARD2) in 16/32 (50%), followed by 5/15 (33%) in 17beta-HSD3 deficiency (17betaHSD3). Others diagnosis related with F to M GD were: partial gonadal dysgenesis (n=3/24; 12%) and 3betaHSD2 (n=1/3; 33%). Both cases of male to female (M to F) GD occurred in partial gonadal dysgenesis (8%; n=2/24). The median of GD age (desire to belong to another gender) was 8 years old (5-9), and the median of gender change itself was 15 years old (10.5 - 20). In F to M GD, gender change was associated with prenatal androgen exposure (p < 001; V=0,461). The psychosexual components showed higher concordance index with final gender (GI - k=0.81; GI - k=0.65 and SO - k=0.85) then with the assigned sex (GI - k=0.1; GI - k=0.25 and SO - k=0.15). Conclusion: Prenatal androgen exposure affects the psychosexual development, favoring more male outcomes. This influence was observed in GI, GR and SO. The degree of external genitalia virilization did not influence the psychosexual development. Female to Male GD is common in 46,XY DSD raised in female social sex, especially in 5ARD2 and 17?HSD3 deficiencies. There is a strong relationship between prenatal androgen exposure and F to M GD. On the other hand, M to F gender change was rare in 46,XY DSD and occurred only in partial gonadal dysgenesis patients
55

Dynamique forcée des systèmes vitreux : des verres de spin aux fluides complexes

Berthier, Ludovic 27 April 2001 (has links) (PDF)
Nous présentons une étude théorique de la dynamique hors équilibre d'une large classe de systèmes microscopiques, dont la caractéristique commune est de présenter, dans certaines conditions expérimentales, une relaxation extrêmement lente (`systèmes vitreux'). Nous abordons tout d'abord le problème du vieillissement de ces systèmes en nous attachant à une comparaison quantitative des deux descriptions théoriques que sont (i) les processus de croissance de domaines, (ii) la solution analytique de modèles désordonnés champ moyen de type verres de spin. Nous abordons ensuite le cas ou la dynamique est forcée par une contrainte extérieure. Cette situation est importante en vue des applications (rhéologie des liquides surfondus et des fluides complexes, compaction lente des matériaux granulaires, etc.), et son étude systématique est un des aspects nouveaux de ce travail. Dans ce cadre, nous étudions tout d'abord numériquement l'influence d'un écoulement sur la séparation de phase d'un mélange binaire. Le diagramme des phases (Température, Forcage) des verres structuraux et des verres de spin est ensuite étudié dans l'approximation de champ moyen. Nous envisageons les deux cas d'un forcage constant non-Hamiltonien, puis Hamiltonien mais dépendant du temps. Ces études fournissent une description à la fois microscopique --forme de la relaxation, température effective définie via le théoreme de fluctuation-dissipation--, et macroscopique --courbes d'écoulement, transitions de phase dynamiques. Les principaux résultats sont testés numériquement sur un liquide surfondu et un verre de spin modéles.
56

Design Of Two-Axis Displacement-Amplifying Compliant Mechanisms Using Topology Optimization

Dinesh, M 01 July 2008 (has links)
This thesis deals with the design of two-axis displacement-amplifying compliant mechanisms (DaCMs) using topology optimization. The two-axis compliant mechanisms considered here are XY positioners and two-axis inertial sensors. A building block approach, with several single-axis DaCMs as building blocks, is used to conceive designs of compliant platforms that provide two orthogonal and independent movement of a common platform. Spring-mass-lever (SML) models of these designs are developed to simplify the analysis and design of the complicated arrangements of building blocks. The XY positioners designed in this work have perfectly de-coupled motion without compromising on the frequency; the best design of the stage has a displacement amplification of five resulting in the enhanced range of 4.2 % of the mechanism size–a significant improvement from the 1.67 %, the maximum range of the designs reported so far. Nearly 100% improvement is observed in the sensitivity of the two-axis accelerometer as compared with an existing design that occupied the same area. Multiple prototypes of XY positioners were fabricated on polypropylene sheets using CNC machining; and on spring steel and aluminium using wire-cut electro discharge machining. Mask layouts for two-layer two-axis accelerometers are designed for micro-fabrication using reactive ion etching and wafer bonding.
57

Aspectos comportamentais e do desenvolvimento psicossexual dos pacientes com distúrbios do desenvolvimento sexual 46,XY na idade adulta / Behavioral and psychosexual aspects of 46,XY DSD individuals at adulthood

Rafael Loch Batista 12 December 2017 (has links)
Introdução: O desenvolvimento psicossexual humano inicia no período pré-natal e é composto pelo papel de gênero (PG), pela identidade de gênero (IG) e pela orientação sexual (OS). Em indivíduos com DDS 46,XY, vários fatores podem comprometer esse desenvolvimento, levando a incongruência de identidade de gênero e à mudança de gênero. Nesses pacientes, a exposição androgênica pré-natal e o grau de virilização da genitália externa tem sido avaliados como possíveis influenciadores destes desfechos, mas seu papel ainda não foi esclarecido. Objetivos: Avaliar os desfechos psicossexuais - IG, PG e OS - e aspectos da vida sexual em uma coorte de indivíduos com DDS 46,XY na idade adulta com diagnostico etiológico caracterizado do ponto de vista clínico e molecular e investigar a influência da exposição androgênica pré-natal e do grau de virilização da genitália externa nesses desfechos e na prevalência de disforia de gênero (DG). Pacientes: 144 pacientes com diagnóstico etiológico confirmado de DDS 46,XY acompanhados do HCFMUSP com idade entre 16 e 60 anos foram incluídos neste estudo. Métodos: Os componentes do desenvolvimento psicossexual (IG, PG, OS) foram avaliados usando questionários e por teste psicológico projetivo (HTP - House-Tree-Person). O escore de Sinnecker foi utilizado para a mensuração do grau de virilização da genitália externa. A exposição androgênica pré-natal foi estimada de acordo com a etiologia do DDS 46,XY. Aspectos da vida sexual foram avaliados através de questionário específico.Todas as variáveis categóricas foram analisadas usando teste X². A força de associação foi avaliada pelo cálculo do V de Cramer. O índice kappa foi usado para avaliar concordância entre resultados dos testes. Resultados: Houve uma associação positiva entre exposição androgênica pré-natal e a maior incidência de desfechos psicossexuais masculinos em indivíduos com maior exposição. O grau de virilização da genitália externa não interferiu nos desfechos psicossexuais. Houve uma prevalência de 19% (27/144) de disforia de gênero em toda a coorte. Em 93% (25/27), a DG foi do sexo feminino para o masculino e ocorreu em 50% (16/32) de casos de deficiência de 5alfa-RD2, seguido de 33% (5/15) dos casos de deficiência da 17beta-HSD3 e se associou com exposição androgênica pré-natal (p < 001; V=0,461), mas não com a virilização da genitália externa. A mediana de idade do desejo de mudar de sexo foi de 8 anos (5 - 9) enquanto que a da idade da mudança de sexo foi 15 anos (10.5 - 20). Os desfechos psicossexuais mostraram maior concordância com o sexo social final (PG - k=0.81; IG - k=0.65 e OS - k=0.85) do que com o sexo de registro (PG - k=0.1; IG - k=0.25 e OS - k=0.15). Quanto a sexualidade, alguns parâmetros (fantasias sexuais, masturbação e parceiro sexual fixo) foram melhores no sexo masculino comparado ao feminino. No entanto, não houveram diferenças em relação aos parâmetros da vida sexual comparando indivíduos do sexo feminino com e sem atipia genital e indivíduos do sexo masculino que mantiveram o sexo social com os que mudaram para este sexo. Conclusões: A exposição androgênica pré-natal influenciou o desenvolvimento psicossexual em indivíduos com DDS 46,XY, de uma forma exposição-dependente, favorecendo desfechos masculinos, enquanto que o grau de virilização da genitália externa não influenciou estes desfechos. A DG do feminino para o masculino foi comum entre esses indivíduos e também foi influenciada pela exposição androgênica pré-natal. Os parâmetros psicossexuais nesses pacientes concorda muito mais com o sexo social final do que com o sexo de registro. A sexualidade dos indivíduos do sexo masculino tem aspectos mais satisfatórios que o feminino. Atipia genital no sexo feminino não afetou a sexualidade destas pacientes assim a sexualidade dos indivíduos que mudaram para o sexo masculino são semelhantes aos que foram registrados no sexo masculino Behavioral and Psychosexual Aspects of 46,XY DSD Individuals At Adulthood / Introduction: The human psychosexual development begins at prenatal period and is composed by gender role, gender identity and sexual orientation. In 46,XY DSD individuals a variety of factors may jeopardize an adequate psychosexual development and sometimes results in desire to change the gender. The effects of prenatal androgen exposure and the impact of atypical genitalia in the psychosexual outcomes have been suggested as influencing factors in the human psychosexual development but there is not conclusive evidence, especially in DDS 46, XY. Methods: We evaluated the psychosexual compounds - gender role (GR) at childhood gender identity (GI) and sexual orientation (SO) in individuals a large cohort of 144 46,XY DSD individuals, 86% of them raised in the female social sex, from a single tertiary medical center. The same psychologist, specialized in DSD, performed the psychosexual evaluation. We used a questionnaire and a projective psychological test (HTP test) to measure the psychosexual compounds. Prenatal androgen exposure was estimated considering the 46,XY etiology. Sinnecker\'s score was used to measure the external genitalia virilization. All ordinal variables were analyzed using Wilcoxon test. Categorical variables were analyzed using X2 test with posterior Cramer\'s V to measure the association strength. The kappa index was calculated as a concordance measure. Results: We found an association between prenatal androgen exposure and major prevalence of male psychosexual outcomes and a higher incidence of female to male gender dysphoria. There was not difference in the psychosexual outcomes according by external genitalia virilization in male and in female individuals. There was an incidence of 19% of gender dysphoria (27 out from 144). In 93% (n=25), the gender change was from female to male (F to M). The ethological diagnosis related with F to M GD were 5alpha-RD2 deficiency (5ARD2) in 16/32 (50%), followed by 5/15 (33%) in 17beta-HSD3 deficiency (17betaHSD3). Others diagnosis related with F to M GD were: partial gonadal dysgenesis (n=3/24; 12%) and 3betaHSD2 (n=1/3; 33%). Both cases of male to female (M to F) GD occurred in partial gonadal dysgenesis (8%; n=2/24). The median of GD age (desire to belong to another gender) was 8 years old (5-9), and the median of gender change itself was 15 years old (10.5 - 20). In F to M GD, gender change was associated with prenatal androgen exposure (p < 001; V=0,461). The psychosexual components showed higher concordance index with final gender (GI - k=0.81; GI - k=0.65 and SO - k=0.85) then with the assigned sex (GI - k=0.1; GI - k=0.25 and SO - k=0.15). Conclusion: Prenatal androgen exposure affects the psychosexual development, favoring more male outcomes. This influence was observed in GI, GR and SO. The degree of external genitalia virilization did not influence the psychosexual development. Female to Male GD is common in 46,XY DSD raised in female social sex, especially in 5ARD2 and 17?HSD3 deficiencies. There is a strong relationship between prenatal androgen exposure and F to M GD. On the other hand, M to F gender change was rare in 46,XY DSD and occurred only in partial gonadal dysgenesis patients
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Quantum Simulations by NMR : Applications to Small Spin Chains and Ising Spin Systems

Rao, K Rama Koteswara January 2014 (has links) (PDF)
Quantum simulations, where controllable quantum systems are used to simulate other quantum systems, originally proposed by Richard Feynman, are one of the most remarkable applications of quantum information science. Compared to computation, quantum simulations require much less number of qubits for the m to be practical. In the work described in this thesis, we have performed a few quantum simulations of small quantum systems using Nuclear Magnetic Resonance(NMR) techniques. These simulations have been used to experimentally demonstrate the underlying interesting quantum protocols. All the experiments presented have been carried out using liquid-state or liquid crystal NMR. Numerical pulse optimization techniques have been utilized in some of the experiments, to achieve better control over the spin systems. The first chapter contains “Introduction” to quantum information processing, NMR, and numerical pulse optimization techniques. In chapter 2, we describe quantum simulation of a 3-spin Heisenberg-XY spin chain having only nearest neighbour interactions. Recently, spin chains having pre-engineered short-range interactions have been proposed to efficiently transfer quantum information between different parts of a quantum information processor. Other important proposals involving these spin chains include generating entangled states and universal quantum computation. However, such engineered interactions do not occur naturally in any system. In such a scenario, the experimental viability of these proposals can be tested by simulating the spin chains in other controllable quantum systems. In this work, we first theoretically study the time evolution of bipartite and tripartite entanglement measures for a 3-spin open ended XY spin chain. Then, by simulating the XY interactions in a 3-spin nuclear spin system, we experimentally generate, (i)a bipartite maximally(pseudo-)entangled state(Bell state) between end qubits, and(ii) multipartite(pseudo-)entangled states(Wand GHZ states),starting from separable pseudo-pure states. Bell state has been generated by using only the natural unitary evolution of the XY spin chain. W-state and GHZ-state have been generated by applying a single-qubit rotation to the second qubit, and a global rotation of all the three qubits respectively after the unitary evolution of the spin chain. In chapter 3, we simulate a 3-spin quantum transverse Ising spin system in a triangular configuration, and show that multipartite quantum correlations can be used to distinguish between the frustrated and non-frustrated regimes in the ground state of this spin system. The ground state of the spin system has been prepared by using adiabatic state preparation method. Gradient ascent pulse engineering technique has been utilized to efficiently realize the adiabatic evolution of the spin system. To analyse the experimental ground state of the system, we employ two different multipartite quantum correlation measures, generated from monogamy studies of bipartite quantum correlations. Chapter 4 contains a digital quantum simulation of the mirror inversion propagator corresponding to the time evolution of an XY spin chain. This simulation has been used to experimentally demonstrate the mirror inversion of quantum states, proposed by Albanese et al.[Phys.Rev.Lett.93,230502(2004)], by which entangled states can be transferred from one end of the chain to the other end. The experiments have been performed in a 5-qubit dipolar coupled nuclear spin system. For simulation, we make use of the recently proposed unitary operator decomposition algorithm along with the numerical pulse optimization techniques, which assisted in achieving high experimental fidelities. Chapter 5 contains a digital quantum simulation of the unitary propagator of a transverse Ising spin chain, which has been used to experimentally demonstrate the perfect state transfer protocol of Di Franco et al. [Phys.Rev.Lett.101,230502(2008)]. The importance of this protocol arises due to the fact that it achieves perfect state transfer from one end of the chain to the other end without the necessity of initializing the intermediate spins of the chain, whereas most of the previously proposed protocols require initialization. The experiments have been performed in a 3-spin nuclear spin system. The simulation has also been used to demonstrate the generation of a GHZ state.
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Topics in the theory of inhomogeneous media: composite superconductors and dielectrics

Kim, Kwangmoo 26 June 2007 (has links)
No description available.
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Aspects hors de l'équilibre de systèmes quantiques unidimensionnels fortement corrélés / Nonequilibrium aspects in strongly correlated one-dimensional quatum systems

Collura, Mario 23 February 2012 (has links)
Dans cette thèse, nous avons répondu à certaines questions ouverts dans le domaine de la dynamique hors équilibre des systèmes quantiques unidimensionnels fermés. Durant ces dernières années, les avancées dans les techniques expérimentales ont revitalisé la recherche théorique en physique de la matière condensée et dans l'optique quantique. Nous avons traité trois sujets différents et en utilisant des techniques à la fois numériques et analytiques. Dans le cadre des techniques numériques, nous avons utilisé des méthodes de diagonalisation exacte, l'algorithme du groupe de renormalisation de la matrice densité en fonction du temps (t-DMRG) et l'algorithme de Lanczos. Au début, nous avons étudié la dynamique quantique adiabatique d'un système quantique près d'un point critique. Nous avons démontré que la présence d'un potentiel de confinement modifie fortement les propriétés d'échelle de la dynamique des observables en proximité du point critique quantique. La densité d'excitations moyenne et l'excès d'énergie, après le croisement du point critique, suivent une loi algébrique en fonction de la vitesse de la trempe avec un exposant qui dépend des propriétés spatio-temporelles du potentiel. Ensuite, nous avons étudié le comportement de bosons ultra-froids dans un réseau optique incliné. En commençant par l'hamiltonien de Bose-Hubbard, dans la limite de Hard-Core bosons, nous avons développé une théorie hydrodynamique qui reproduit exactement l'évolution temporelle d'une partie des observables du système. En particulier, nous avons observé qu'une partie de bosons reste piégée, et oscille avec une fréquence qui dépend de la pente du potentiel, au contraire, une autre partie est expulsée hors de la rampe. Nous avons également analysé la dynamique du modèle de Bose-Hubbard en utilisant l'algorithme t-DMRG et l'algorithme de Lanczos. De cette façon, nous avons mis en évidence le rôle de la non-intégrabilité du modèle dans son comportement dynamique. Enfin, nous avons abordé le problème de la thermalisation dans un système quantique étendu. À partir de considérations générales, nous avons introduit la notion de profil de température hors équilibre dans une chaîne des bosons à coeur dure. Nous avons analysé la dynamique du profil de temperature et, notamment, ses propriétés d'échelle / In this thesis we have addressed some open questions on the out-of-equilibrium dynamics of closed one-dimensional quantum systems. In recent years, advances in experimental techniques have revitalized the theoretical research in condensed matter physics and quantum optics. We have treated three different subjects using both numerical and analytical techniques. As far as the numerical techniques are concerned, we have used essentially exact diagonalization methods, the adaptive time-dependent density-matrix renormalization-group algorithm (t-DMRG) and the Lanczos algorithm. At first, we studied the adiabatic quantum dynamics of a quantum system close to a critical point. We have demonstrated that the presence of a confining potential strongly affects the scaling properties of the dynamical observables near the quantum critical point. The mean excitation density and the energy excess, after the crossing of the critical point, follow an algebraic law as a function of the sweeping rate with an exponent that depends on the space-time properties of the potential. After that, we have studied the behavior of ultra-cold bosons in a tilted optical lattice. Starting with the Bose-Hubbard Hamiltonian, in the limit of Hard-Core bosons, we have developed a hydrodynamic theory that exactly reproduces the temporal evolution of some of the observables of the system. In particular, it was observed that part of the boson density remains trapped, and oscillates with a frequency that depends on the slope of the potential, whereas the remaining packet part is expelled out of the ramp. We have also analyzed the dynamics of the Bose-Hubbard model using the tDMRG algorithm and the Lanczos algorithm. In this way we have highlighted the role of the non-integrability of the model on its dynamical behavior. Finally, we have addressed the issue of thermalization in an extended quantum system. Starting from quite general considerations, we have introduced the notion of out-of-equilibrium temperature profile in a chain of Hard-Core bosons. We have analyzed the dynamics of the temperature profile and especially its scaling properties

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