998 resultados para Sean-Ghaeilge


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To determine whether human X-linked neonatal diabetes mellitus, enteropathy and endocrinopathy syndrome (IPEX; MIM 304930) is the genetic equivalent of the scurfy (sf) mouse, we sequenced the human ortholog (FOXP3) of the gene mutated in scurfy mice (Foxp3), in IPEX patients. We found four non-polymorphic mutations. Each mutation affects the forkhead/winged-helix domain of the scurfin protein, indicating that the mutations may disrupt critical DNA interactions.

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Computational simulations of the title reaction are presented, covering a temperature range from 300 to 2000 K. At lower temperatures we find that initial formation of the cyclopropene complex by addition of methylene to acetylene is irreversible, as is the stabilisation process via collisional energy transfer. Product branching between propargyl and the stable isomers is predicted at 300 K as a function of pressure for the first time. At intermediate temperatures (1200 K), complex temporal evolution involving multiple steady states begins to emerge. At high temperatures (2000 K) the timescale for subsequent unimolecular decay of thermalized intermediates begins to impinge on the timescale for reaction of methylene, such that the rate of formation of propargyl product does not admit a simple analysis in terms of a single time-independent rate constant until the methylene supply becomes depleted. Likewise, at the elevated temperatures the thermalized intermediates cannot be regarded as irreversible product channels. Our solution algorithm involves spectral propagation of a symmetrised version of the discretized master equation matrix, and is implemented in a high precision environment which makes hitherto unachievable low-temperature modelling a reality.

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A new method is presented to determine an accurate eigendecomposition of difficult low temperature unimolecular master equation problems. Based on a generalisation of the Nesbet method, the new method is capable of achieving complete spectral resolution of the master equation matrix with relative accuracy in the eigenvectors. The method is applied to a test case of the decomposition of ethane at 300 K from a microcanonical initial population with energy transfer modelled by both Ergodic Collision Theory and the exponential-down model. The fact that quadruple precision (16-byte) arithmetic is required irrespective of the eigensolution method used is demonstrated. (C) 2001 Elsevier Science B.V. All rights reserved.

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Time-dependent wavepacket evolution techniques demand the action of the propagator, exp(-iHt/(h)over-bar), on a suitable initial wavepacket. When a complex absorbing potential is added to the Hamiltonian for combating unwanted reflection effects, polynomial expansions of the propagator are selected on their ability to cope with non-Hermiticity. An efficient subspace implementation of the Newton polynomial expansion scheme that requires fewer dense matrix-vector multiplications than its grid-based counterpart has been devised. Performance improvements are illustrated with some benchmark one and two-dimensional examples. (C) 2001 Elsevier Science B.V. All rights reserved.

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We analyzed the mouse Representative Transcript and Protein Set for molecules involved in brain function. We found full-length cDNAs of many known brain genes and discovered new members of known brain gene families, including Family 3 G-protein coupled receptors, voltage-gated channels, and connexins. We also identified previously unknown candidates for secreted neuroactive molecules. The existence of a large number of unique brain ESTs suggests an additional molecular complexity that remains to be explored. A list of genes containing CAG stretches in the coding region represents a first step in the potential identification of candidates for hereditary neurological disorders.

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We have developed a computational strategy to identify the set of soluble proteins secreted into the extracellular environment of a cell. Within the protein sequences predominantly derived from the RIKEN representative transcript and protein set, we identified 2033 unique soluble proteins that are potentially secreted from the cell. These proteins contain a signal peptide required for entry into the secretory pathway and lack any transmembrane domains or intracellular localization signals. This class of proteins, which we have termed the mouse secretome, included >500 novel proteins and 92 proteins

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In this paper we propose a second linearly scalable method for solving large master equations arising in the context of gas-phase reactive systems. The new method is based on the well-known shift-invert Lanczos iteration using the GMRES iteration preconditioned using the diffusion approximation to the master equation to provide the inverse of the master equation matrix. In this way we avoid the cubic scaling of traditional master equation solution methods while maintaining the speed of a partial spectral decomposition. The method is tested using a master equation modeling the formation of propargyl from the reaction of singlet methylene with acetylene, proceeding through long-lived isomerizing intermediates. (C) 2003 American Institute of Physics.

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In this paper we propose a novel fast and linearly scalable method for solving master equations arising in the context of gas-phase reactive systems, based on an existent stiff ordinary differential equation integrator. The required solution of a linear system involving the Jacobian matrix is achieved using the GMRES iteration preconditioned using the diffusion approximation to the master equation. In this way we avoid the cubic scaling of traditional master equation solution methods and maintain the low temperature robustness of numerical integration. The method is tested using a master equation modelling the formation of propargyl from the reaction of singlet methylene with acetylene, proceeding through long lived isomerizing intermediates. (C) 2003 American Institute of Physics.

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Bound and resonance states of HO2 have been calculated quantum mechanically by the Lanczos homogeneous filter diagonalization method [Zhang and Smith, Phys. Chem. Chem. Phys. 3, 2282 (2001); J. Chem. Phys. 115, 5751 (2001)] for nonzero total angular momentum J = 1,2,3. For lower bound states, agreement between the results in this paper and previous work is quite satisfactory; while for high lying bound states and resonances these are the first reported results. A helicity quantum number V assignment (within the helicity conserving approximation) is performed and the results indicate that for lower bound states it is possible to assign the V quantum numbers unambiguously, but for resonances it is impossible to assign the V helicity quantum numbers due to strong mixing. In fact, for the high-lying bound states, the mixing has already appeared. These results indicate that the helicity conserving approximation is not good for the resonance state calculations and exact quantum calculations are needed to accurately describe the reaction dynamics for HO2 system. Analysis of the resonance widths shows that most of the resonances are overlapping and the interferences between them lead to large fluctuations from one resonance to another. In accord with the conclusions from earlier J = 0 calculations, this indicates that the dissociation of HO2 is essentially irregular. (C) 2003 American Institute of Physics.

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We have recently developed a scaleable Artificial Boundary Inhomogeneity (ABI) method [Chem. Phys. Lett.366, 390–397 (2002)] based on the utilization of the Lanczos algorithm, and in this work explore an alternative iterative implementation based on the Chebyshev algorithm. Detailed comparisons between the two iterative methods have been made in terms of efficiency as well as convergence behavior. The Lanczos subspace ABI method was also further improved by the use of a simpler three-term backward recursion algorithm to solve the subspace linear system. The two different iterative methods are tested on the model collinear H+H2 reactive state-to-state scattering.

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In the rodent central nervous system (CNS) during the five days prior to birth, both growth hormone (GH) and its receptor (GHR) undergo transient increases in expression to levels considerably higher than those found postnatally. This increase in expression coincides with the period of neuronal programmed cell death (PCD) in the developing CNS. To evaluate the involvement of growth hormone in the process of PCD, we have quantified the number of motoneurons in the spinal cord and brain stem of wild type and littermate GHR-deficient mice at the beginning and end of the neuronal PCD period. We found no change in motoneuron survival in either the brachial or lumbar lateral motor columns of the spinal cord or in the trochlear, trigeminal, facial or hypoglossal nuclei in the brain stem. We also found no significant differences in spinal cord volume, muscle fiber diameter, or body weight of GHR-deficient fetal mice when compared to their littermate controls. Therefore, despite considerable in vitro evidence for GH action on neurons and glia, genetic disruption of GHR signalling has no effect on prenatal motoneuron number in the mouse, under normal physiological conditions. This may be a result of compensation by the signalling of other neurotrophic cytokines.

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Este trabalho faz uma breve revis??o sobre as diferentes maneiras de se estruturar uma iniciativa or??ament??ria de g??nero, seja ela elaborada pelo governo ou pela sociedade civil, em n??vel local ou nacional, considerando todo o or??amento ou setores selecionados e dependendo do est??gio do ciclo or??ament??rio em que ela ?? realizada. Este estudo delineia uma estrutura para a an??lise de g??nero de or??amentos, relacionando os insumos ??s atividades, aos resultados e aos impactos e, a partir da??, apresenta alguns exemplos de an??lises de or??amento a partir da perspectiva de g??nero, em diferentes momentos do ciclo or??ament??rio, buscando experi??ncias em diferentes pa??ses. Tamb??m destaca dois princ??pios chave na an??lise do or??amento com enfoque no g??nero, a saber: 1) a avalia????o do impacto do or??amento tanto sobre o indiv??duo como sobre a fam??lia; e 2) o reconhecimento da contribui????o econ??mica do trabalho dom??stico n??o remunerado, a cargo basicamente das mulheres.

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As sociedades estatais s??o importantes organiza????es societ??rias, que podem servir ao administrador p??blico para a realiza????o de atividades econ??micas que configurem relevante interesse coletivo ou motivo de seguran??a nacional. Com a finalidade de adequarem-se aos limites de investimento p??blico e com vistas ao cumprimento do princ??pio da efici??ncia, elas podem utilizar-se de mecanismos societ??rios e contratuais de gest??o disponibilizados a empresas, sejam elas estatais ou privadas. Os movimentos societ??rios, os mecanismos de controle e partilha de controle e a ado????o das pr??ticas de governan??a corporativa s??o alternativas jur??dicas disponibilizadas aos administradores das empresas estatais. A an??lise do caso da Companhia Paranaense de Energia El??trica (Copel) ?? realizada no artigo com o prop??sito de auxiliar na visualiza????o da aplica????o de tais institutos.

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Os Conselhos Gestores s??o f??runs h??bridos onde se viabiliza a participa????o popular no desenho das pol??ticas p??blicas, nas negocia????es de interesses da coletividade, na elabora????o de programas e projetos sociais e na fiscaliza????o das a????es governamentais. O significado e a dimens??o dos Conselhos para a democracia participativa s??o enormes, justificando a import??ncia da realiza????o deste estudo, que se baseou na an??lise explorat??ria de 12 Conselhos locais do munic??pio mineiro de Vi??osa, com o objetivo de avaliar o desempenho dos mesmos. A avalia????o do desempenho levou em considera????o os mesmos par??metros dimensionais, tanto para a coleta de dados prim??rios quanto para a coleta secund??ria. A coleta de dados prim??rios foi realizada a partir da aplica????o de question??rios semi-estruturados aos presidentes dos Conselhos em an??lise. Utilizou-se o programa SPSS, vers??o 15.0, para an??lise estat??stica das quest??es objetivas dos question??rios e a t??cnica de an??lise de conte??do para exame das quest??es abertas. Ap??s essa etapa, realizou-se um workshop com os presidentes dos Conselhos, visando ?? obten????o de novos dados e informa????es. Os Conselhos municipais analisados apresentaram resultados pouco discrepantes entre a teoria aplicada ao tema e a sua efetiva pr??tica no campo p??blico. Contudo, a pesquisa revelou que o grau de desenvolvimento institucional dos Conselhos n??o ?? homog??neo, ou seja, h?? alguns melhores gestores que outros. A escolha independente e democr??tica dos membros n??o-governamentais dos Conselhos em Vi??osa revelou o seu grau de independ??ncia do Poder Executivo. Por??m, a capacita????o de conselheiros precisa ser implementada para evitar uma desfigura????o dos Conselhos. No que tange ?? governan??a, destacouse em Vi??osa o seu grau e formas de aplicabilidade observadas na gest??o de v??rias pol??ticas. Da mesma forma, foi observado um n??vel de governabilidade que confere legitimidade ??s pol??ticas implementadas. Por fim, verificou-se que a efetividade da accountability societal tem sido instrumentalizada pelos Conselhos no ??mbito das diversas pol??ticas setoriais. J?? os dados secund??rios da an??lise foram obtidos por meio das s??nteses dos relat??rios de fiscaliza????o de munic??pios do Estado de Minas Gerais, realizadas pela Controladoria Geral da Uni??o. Foram identificados todos os registros pertinentes aos Conselhos Gestores Municipais do Estado de Minas Gerais, no per??odo de 2003 a 2006. Verificou-se que os maiores problemas se referem aos Conselhos Municipais de Sa??de e Assist??ncia Social. Entre as in??meras falhas apontadas, destacam-se problemas graves na constitui????o e operacionaliza????o dos Conselhos, resultando na inoper??ncia desses mecanismos nos munic??pios fiscalizados. A avalia????o do desempenho dos Conselhos locais de Vi??osa possibilitou concluir que esses mecanismos apresentaram um desempenho bem satisfat??rio na gest??o e controle das pol??ticas p??blicas no munic??pio.