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Despite extensive efforts to confirm a direct association between Chlamydia pneumoniae and atherosclerosis, different laboratories continue to report a large variability in detection rates. In this study, we analyzed multiple sections from atherosclerotic carotid arteries from 10 endartectomy patients to determine the location of C. pneumoniae DNA and the number of sections of the plaque required for analysis to obtain a 95% confidence of detecting the bacterium. A sensitive nested PCR assay detected C. pneumoniae DNA in all patients at one or more locations within the plaque. On average, 42% (ranging from 5 to 91%) of the sections from any single patient had C. pneumoniae DNA present. A patchy distribution of C. pneumoniae in the atherosclerotic lesions was observed, with no area of the carotid having significantly more C. pneumoniae DNA present. If a single random 30-mum-thick section was tested, there was only a 35.6 to 41.6% (95% confidence interval) chance of detecting C. pneumoniae DNA in a patient with carotid artery disease. A minimum of 15 sections would therefore be required to obtain a 95% chance of detecting all true positives. The low concentration and patchy distribution of C. pneumoniae DNA in atherosclerotic plaque appear to be among the reasons for inconsistency between laboratories in the results reported.

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Experimental studies on phase equilibria and liquidus in the multicomponent system PbO-ZnO-CaO-SiO2-FeO-Fe2O3 in air have been conducted over the temperature range between 1323 K (1050 degreesC) and 1623 K (1350 degreesC) to characterize the phase relations of the complex slag systems encountered in lead and zinc blast furnace sinters. The liquidus in two pseudoternary sections ZnO-Fe2O3-(PbO + CaO + SiO2) with the CaO/SiO2 weight ratio of 0.933 and PbO/(CaO + SiO2) weight ratios of 2.0 and 3.2 have been constructed.

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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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Objective To investigate the effect of lipophilicity on the percutaneous penetration of a homologous series of alcohols through canine skin Design Skin harvested from Greyhound thorax was placed in Franz-type diffusion cells and the in vitro passage of radio-labelled (C-14) alcohols (ethanol, butanol, hexanol and octanol (Log P 0.19 - 3.0)) through separate skin sections was measured in replicates of five. Permeability coefficient (k(P), cm/h), maximum flux (J(max), mol/cm(2)/h) and residue remaining within the skin were determined. Results The k(P) increased with increasing lipophilicity (6.2 x 10(-4) +/- 1.6 x 10(-4) cm/h for ethanol to 1.8 x 10(-2) 3.6 x 10(-3) cm/h for octanol). Alcohol residues remaining within each skin sample followed a similar pattern. An exponential decrease in Jmax with increasing lipophilicity was observed. Conclusion Changes in canine skin permeability occur with increasing alcohol lipophilicity. This finding has practical consequences for the design of topical formulations and optimisation of drug delivery through animal skin.

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Skinks from the genera Eulamprus, Gnypetoscincus and Nangura are a prominent component of the reptile fauna of the mesic forests of the east coast of Australia and have been the subject of numerous ecological studies. Highly conserved morphology and the retention of ancestral traits have limited our understanding of the relationships within and among these genera beyond an initial identification of species groups within Eulamprus. To address this deficit and to explore the relationships between Eulamprus and the monotypic genera Nangura and Gnypetoscincus, sections of two mitochondrial genes (ND4 and 16S rRNA) were sequenced and subjected to Bayesian phylogenetic analysis. This phylogenetic analysis supports recognition of the three species groups proposed for Eulamprus (murrayi, quoyii and tenuis) and indicates that this genus is paraphyletic, with Gnypetoscincus and Nangura being proximal to basal lineages of the tenuis group. To resolve these and broader problems of paraphyly, we suggest that each of the species groups from 'Eulamprus' should be recognised as a distinct genus. The phylogenetically and ecologically distinct water skinks of the quoyii group would be retained within Eulamprus and the diverse species of the tenuis group allocated to Concinnia. We suggest placing the monophyletic murrayi group, endemic to the rainforests of central eastern Australia, in a new genus ( yet to be formally described). The sequencing data also revealed the existence of a genetically divergent but morphologically cryptic lineage within E. murrayi and substantial diversity within E. quoyii. There is evidence for two major habitat shifts from rainforest towards drier habitats, one leading to the quoyii group and the second defining a clade of three species within the tenuis complex. These ecological transitions may represent adaptations to general drying across eastern Australia during the late Miocene - Pliocene. Each of the major areas of east coast tropical or subtropical rainforest contains multiple phylogenetically diverse endemic species, reflecting the long-term persistence and high conservation value of wet forest habitats in each area.

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Background/Aims: The role of cytokines in hepatic injury has been examined for many liver diseases however little is known of the cytokine involvement in haemochromatosis. The aim of the current study was to examine the hepatic gene expression of potential proinflammatory and profibrogenic cytokines in haemochromatosis. Methods: Interferon-gamma, interleukin-10, transforming growth factor-beta(1) and tumor necrosis factor-alpha mRNA expression was assessed in liver tissue from 20 haemochromatosis patients, eight controls and eight chronic hepatitis C patients. To assess the immunophenotype of the inflammatory infiltrate in haemochromatosis, liver sections were subjected to immunohistochemistry using markers for macrophages (CD68, HAM56, MAC387) or T cells (CD3 and CD45RO). Results: Interferon-gamma mRNA was increased in both haemochromatosis (0.29+/-0.08%, P=0.01) and hepatitis C patients (1.02+/-0.32%, P=0.03) compared to controls (0.04+/-0.01%). Interleukin-10 mRNA was significantly decreased in both haemochromatosis and hepatitis C patients (0.01+/-0.003%, P=0.008 and 0.03+/-0.015%, P=0.02, respectively) compared to controls (0.12+/-0.01%). CD3 positive T-cell number was significantly correlated with increasing hepatic iron concentration (r=0.56, P=0.03). Conclusions: This study has demonstrated a distinct pattern of cytokine gene expression in haemochromatosis, which resembles that of inflammatory conditions such as chronic hepatitis C. These factors may play a role in the development of iron-induced hepatic fibrosis in haemochromatosis. (C) 2003 European Association for the Study of the Liver. Published by Elsevier Science B.V. All rights reserved.

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This paper delineates the development of a prototype hybrid knowledge-based system for the optimum design of liquid retaining structures by coupling the blackboard architecture, an expert system shell VISUAL RULE STUDIO and genetic algorithm (GA). Through custom-built interactive graphical user interfaces under a user-friendly environment, the user is directed throughout the design process, which includes preliminary design, load specification, model generation, finite element analysis, code compliance checking, and member sizing optimization. For structural optimization, GA is applied to the minimum cost design of structural systems with discrete reinforced concrete sections. The design of a typical example of the liquid retaining structure is illustrated. The results demonstrate extraordinarily converging speed as near-optimal solutions are acquired after merely exploration of a small portion of the search space. This system can act as a consultant to assist novice designers in the design of liquid retaining structures.

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A method is presented for calculating the currents and winding patterns required to design independent zonal and tesseral shim coils for magnetic resonance imaging. Both actively shielded and unshielded configurations are considered, and the region of interest can be located asymmetrically with respect to the coil's length. Streamline, target-field and Fourier-series methods are utilized. The desired target-field is specified at two cylindrical radii, on and inside a circular conducting cylinder of length 2L and radius a. The specification is over some asymmetric portion pL < z < qL of the coil's length (-1 < p < q < 1). Arbitrary functions are used in the outer sections, -L < z < pL and qL < z < L, to ensure continuity of the magnetic field across the entire length of the coil. The entire field is then periodically extended as a half-range cosine Fourier series about either end of the coil. The resultant Fourier coefficients are then substituted into the Fourier-series expressions for the internal and external magnetic fields, and current densities and stream functions on both the primary coil and shield. A contour plot of the stream function directly gives the required coil winding patterns. Spherical harmonic analysis and shielding analysis on field calculations from a ZX shim coil indicate that example designs and theory are well matched.

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This paper describes the buckling phenomenon of a tubular truss with unsupported length through a full-scale test and presents a practical computational method for the design of the trusses allowing for the contribution of torsional stiffness against buckling, of which the effect has never been considered previously by others. The current practice for the design of a planar truss has largely been based on the linear elastic approach which cannot allow for the contribution of torsional stiffness and tension members in a structural system against buckling. The over-simplified analytical technique is unable to provide a realistic and an economical design to a structure. In this paper the stability theory is applied to the second-order analysis and design of the structural form, with detailed allowance for the instability and second-order effects in compliance with design code requirements. Finally, the paper demonstrates the application of the proposed method to the stability design of a commonly adopted truss system used in support of glass panels in which lateral bracing members are highly undesirable for economical and aesthetic reasons.

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Two methods were compared for determining the concentration of penetrative biomass during growth of Rhizopus oligosporus on an artificial solid substrate consisting of an inert gel and starch as the sole source of carbon and energy. The first method was based on the use of a hand microtome to make sections of approximately 0.2- to 0.4-mm thickness parallel to the substrate surface and the determination of the glucosamine content in each slice. Use of glucosamine measurements to estimate biomass concentrations was shown to be problematic due to the large variations in glucosamine content with mycelial age. The second method was a novel method based on the use of confocal scanning laser microscopy to estimate the fractional volume occupied by the biomass. Although it is not simple to translate fractional volumes into dry weights of hyphae due to the lack of experimentally determined conversion factors, measurement of the fractional volumes in themselves is useful for characterizing fungal penetration into the substrate. Growth of penetrative biomass in the artificial model substrate showed two forms of growth with an indistinct mass in the region close to the substrate surface and a few hyphae penetrating perpendicularly to the surface in regions further away from the substrate surface. The biomass profiles against depth obtained from the confocal microscopy showed two linear regions on log-linear plots, which are possibly related to different oxygen availability at different depths within the substrate. Confocal microscopy has the potential to be a powerful tool in the investigation of fungal growth mechanisms in solid-state fermentation. (C) 2003 Wiley Periodicals, Inc.

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O objetivo deste texto ?? iniciar um levantamento da dificuldades impostas ?? reforma administrativa a partir da considera????o do problema da neutralidade da burocracia versus o requisito da autonomia de decis??o, elemento fundamental do Modelo de Administra????o P??blica Gerencial. Tal problema assume especial relev??ncia frente aos objetivos de aumentar a governan??a do Estado e constitui um dos desafios centrais do Plano Diretor da Reforma do Aparelho do Estado, particularmente no que diz respeito ?? forma de administra????o do chamado ???n??cleo estrat??gico??? ??? respons??vel pela defini????o das leis e pol??ticas p??blicas ??? e das ???atividades exclusivas de Estado??? ??? caracterizadas pelo exerc??cio do poder de legislar e tributar, fiscalizando, regulamentando e transferindo recursos. Para isso, a discuss??o est?? organizada em quatro se????es. Na primeira, s??o rapidamente apresentados os conceitos de governabilidade e governan??a, com ??nfase no fato de que a distin????o entre eles representa apenas um recurso anal??tico. Na segunda se????o, a partir das distin????es cl??ssicas de Max Weber entre pol??tica e administra????o, pol??ticos e burocratas, busca-se caracterizar a neutralidade burocr??tica e mostrar que representa, na realidade, apenas um dos elementos de uma constru????o t??pico ideal, cada vez mais distante de qualquer correspond??ncia com o mundo real. Em seguida, comenta-se rapidamente o processo de mudan??a do modelo de administra????o p??blica; e s??o apresentadas algumas das caracter??sticas do chamado Modelo de Administra????o P??blica Gerencial que, em lugar da neutralidade, implicam elevado grau de autonomia por parte dos agentes burocr??ticos. Por fim, s??o tecidas algumas considera????es, procurando mostrar que, da mesma maneira que a neutralidade, a autonomia burocr??tica apresenta dificuldades e que a proposta da ???autonomia imersa??? ou ???autonomia inserida??? exibe implica????es que merecem reflex??o mais demorada.

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Este trabalho discute raz??es pelas quais se deve esperar que governos representativos mantenham um programa institucionalizado de pesquisa de opini??o p??blica. O argumento divide-se em quatro se????es. Na primeira, discutem-se raz??es te??ricas e operacionais para que os governos acompanhem ao longo do tempo o comportamento de opini??es e prefer??ncias dos cidad??os. Na segunda, descrevem-se as consequ??ncias da (im)popularidade governamental, medida sint??tica e crucial da rela????o entre representantes e representados. Em seguida, uma terceira se????o aponta poss??veis fronteiras ou limites que permitiriam distinguir o escopo das pesquisas de opini??o p??blica realizadas pelos governos daquele das conduzidas com prop??sito cient??fico, mercadol??gico e, sobretudo, eleitoral. Finalmente, a quarta se????o descreve a recente experi??ncia do governo brasileiro nessa ??rea

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Este estudo avaliou o impacto do Programa de Fortalecimento e Melhoria da Qualidade dos Hospitais do SUS-MG (Pro-Hosp). Para tanto, foi empregado o m??todo diferen??as-em-diferen??as, que permite avaliar o impacto de pol??ticas p??blicas quando o indicador avaliado ?? observado em mais de um per??odo no tempo. Foram selecionados quatro indicadores de desempenho hospitalar: a propor????o m??dia de ces??rea, a taxa m??dia de ocupa????o, a taxa m??dia de mortalidade e o tempo m??dio de perman??ncia. Constatou-se que o Pro-Hosp teve impacto na propor????o m??dia de ces??reas no sentido esperado, ou seja, de reduzi-las

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Nas ??ltimas duas d??cadas, tem-se observado um processo cada vez mais intenso de proposi????o de indicadores de monitoramento e avalia????o da a????o governamental, assim como de indicadores sociais gerais, dentro e fora das organiza????es p??blicas. No campo das pol??ticas educacionais, especificamente, sob os ausp??cios do Plano de Desenvolvimento da Educa????o (PDE), prop??s-se mais uma dessas medidas, o ??ndice de Desenvolvimento da Educa????o B??sica (Ideb). O objetivo deste trabalho ?? analisar seus usos, caracter??sticas e limita????es, al??m de propor medidas alternativas e complementares para acompanhar os resultados e impactos do PDE. O texto est?? organizado em cinco se????es. Na primeira se????o discute-se o papel e o uso dos indicadores no ciclo de pol??ticas p??blicas, em especial no monitoramento e avalia????o de programas. A se????o seguinte tem car??ter mais metodol??gico, tratando da constru????o de indicadores sint??ticos, seus usos e limita????es. Apresenta-se, ent??o, o Ideb e se discute suas caracter??sticas, potencialidades e restri????es para acompanhamento da agenda da pol??tica educacional. As duas ??ltimas se????es s??o dedicadas ?? apresenta????o de uma proposta de indicador alternativo ??? o Ideb+ e o Painel PIdeb+ ??? para monitoramento do PDE.

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O artigo versa sobre o debate travado entre Say e Sismondi a respeito da possibilidade de saturação geral dos mercados. Na primeira seção, descreve-se o contexto histórico da Europa continental nas primeiras décadas do século 19, destacando-se as particularidades da experiência francesa de industrialização ante a liderança britânica nesse campo. A seguir, traça-se breve perfil da formação intelectual de Say a fim de apresentar sua visão sobre o funcionamento dos mercados. Na continuação, examina-se a perspectiva histórica de Sismondi em sua crítica da ortodoxia clássica, bem como sua versão para a tendência do sistema capitalista à superprodução. Nas duas últimas partes, recuperam-se os comentários recíprocos de Say e Sismondi a respeito de suas divergências teóricas sobre os limites da acumulação de capital.