Ultrasonic absorption in polymer gel dosimeters

Ultrasonic absorption in polymer gel dosimeters was investigated. An ultrasonic interferometer was used to study the frequency (f) dependence of the absorption coefficient (alpha) in a polyacrylamide gel dosimeter (PAG) in the frequency range 5-20 MHz. The frequency dependence of ultrasonic absorption deviated from that of an ideal viscous fluid. The presence of relaxation mechanisms was evidenced by the frequency dependence of alpha/f(2) and the dispersion in ultrasonic velocity. It was concluded that absorption in polymer gel dosimeters is due to a number of relaxation processes which may include polymer-solvent interactions as well as relaxation due to motion of polymer side groups. The dependence of ultrasonic absorption on absorbed dose and formulation was also investigated in polymer gel dosimeters as a function of pH and chemical composition. Changes in dosimeter pH and chemical composition resulted in a variation in ultrasonic dose response curves. The observed dependence on pH was considered to be due to pH induced modifications in the radiation yield while changes in chemical composition resulted in differences in polymerisation kinetics. (C) 2003 Elsevier B.V. All rights reserved.

Part 1. Growth, carcass and meat quality parameters of male goats: effects of genotype and liveweight at slaughter

Male kids (110) from six goat genotypes, i.e. Boer x Angora (BA), Boer x Feral (1317), Boer x Saanen (BS), Feral x Feral (FF), Saanen x Angora (SA) and Saanen x Feral (SF) and two slaughter weight groups, i.e. Capretto and Chevon (liveweight at slaughter 14-22 and 30-35 kg, respectively) were compared for growth, carcass and meat quality characteristics. Due to their better growth rate, kids from BS and SF genotypes reached the required liveweight for slaughter earlier than kids from other Genotypes used in the study. Chevon kids had a significantly (P < 0.05) lower average daily gain (119 g per day) compared to Capretto kids (171 g per day). SA, SF and FF kids deposited more internal fat in comparison to kids from other genotypes. The dressing percentage of kids ranged from 51 to 54%, with significant differences between genotypes. BS and SF kids had longer carcasses. while BF kids had larger eye muscle area compared to other genotypes. Goat carcasses had a thin subcutaneous fat cover (1.6-2.2 mm). Genotype had a significant (P < 0.05) influence on cooking loss, pigment concentration and muscle colour parameters (CIE L*, a* and b* values). As denoted by the higher V and fibre optic probe values and lower subjective muscle score, the longissimus muscle colour was lighter for BS kids than other genotypes. Cooked meat from the BF kids had lower shear force values and better sensory scores compared to other genotypes. A significant (P < 0.05) decrease in muscle tenderness was observed from Capretto to Chevon carcasses, whereas cooked meat from these two slaughter weight groups was equally accepted (P > 0.05) by the panellists. (C) 2003 Elsevier Science B.V. All rights reserved.

Effects of rosiglitazone and linoleic acid on human preadipocyte differentiation

Background Peroxisome proliferator activated receptor gamma (PPARgamma) is a ligand-activated transcription factor known to be central to both adipose tissue development and insulin action. Growth of adipose tissue requires differentiation of preadipocytes with acquisition of specific cellular functions including insulin sensitivity, leptin secretion and the capacity to store triglyceride. Dietary fatty acids and members of the thiazolidinedione class of compounds have been reported to influence adipogenesis at the transcriptional level. Here, we compare the effects of a dietary fatty acid, linoleic acid, and a thiazolidinedione, rosiglitazone, on biochemical and functional aspects of human preadipocyte differentiation in vitro . Materials and methods Human omental and subcutaneous preadipocytes were subcultured 2-3 times and subsequently differentiated for 21 days in the presence of either linoleic acid or rosiglitazone. Differentiation was assessed using a number of biochemical and functional parameters. Results Omental and subcutaneous preadipocytes differentiated in the presence of linoleic acid showed marked cytoplasmic triacylglycerol accumulation however, no biochemical markers of differentiation (LPL expression, G3PDH gene expression and enzyme activity and leptin expression or secretion) were detected. In contrast, treatment of these cells with rosiglitazone induced full biochemical differentiation as judged by all markers assessed, despite comparatively little lipid accumulation. The rosiglitazone effects were subcutaneous depot-specific. Cells treated with linoleic acid showed decreased glucose uptake cf rosiglitazone-treated cells. A luciferase reporter assay demonstrated that rosiglitazone potently activates h-peroxisome proliferator activated receptor gamma while linoleic acid had no effect. Conclusions These studies demonstrate that (a) human preadipocytes have the potential to accumulate triacylglycerol irrespective of their stage of biochemical differentiation; (b) while omental preadipocytes are refractory to biochemical differentiation in vitro , they are able to accumulate triacylglycerol; and (c) rosiglitazone and linoleic acid may exert their effects via different biochemical pathways.

Biaxial failure model for fiber reinforced concrete

Steel fiber reinforced concrete (SFRC) is widely applied in the construction industry. Numerical elastoplastic analysis of the macroscopic behavior is complex. This typically involves a piecewise linear failure curve including corner singularities. This paper presents a single smooth biaxial failure curve for SFRC based on a semianalytical approximation. Convexity of the proposed model is guaranteed so that numerical problems are avoided. The model has sufficient flexibility to closely match experimental results. The failure curve is also suitable for modeling plain concrete under biaxial loading. Since this model is capable of simulating the failure states in all stress regimes with a single envelope, the elastoplastic formulation is very concise and simple. The finite element implementation is developed to demonstrate the conciseness and the effectiveness of the model. The computed results display good agreement with published experimental data.

On the evaluation of some differential formulations for the pom-pom constitutive model

In recent years, progress has been made in modelling long chain branched polymers by the introduction of the so-called pompom model. Initially developed by McLeish and Larson (1998), the model has undergone several improvements or alterations, leading to the development of new formulations. Some of these formulations however suffer from certain mathematical defects. The purpose of the present paper is to review some of the formulations of the pom-pom constitutive model, and to investigate their possible mathematical defects. Next, an alternative formulation is proposed, which does not appear to exhibit mathematical defects, and we explore its modelling performance by comparing the predictions with experiments in non-trivial rheometric flows of an LDPE melt. The selected rheometric flows are the double step strain, as well as the large amplitude oscillatory shear experiments. For LAOS experiments, the comparison involves the use of Fourier-transform analysis.

Analysis of multicomponent adsorption kinetics on activated carbon

An integrated mathematical model for the kinetics of multicomponent adsorption on microporous carbon was developed. Transport in this bidisperse solid is represented by balance equations in the macropore and micropore phases, in which gas-phase diffusion dominates the mass transfer in the macropores, with the phenomenological diffusivities represented by the generalized Maxwell-Stefan (GMS) formulation. Viscous flow also contributes to the macropore fluxes and is included in the MS expressions. Diffusion of the adsorbed phase controls the mass transfer in the micro ore phase, p which is also described in a similar way by the MS method. The adsorption isotherms are represented by a new heterogeneous modified vacancy solution theory formulation of adsorption, which has proved to be a robust method for adsorption on activated carbons. The model is applied to the coadsorption and codesorption of C2H6 and C3H8 on Ajax and Norit carbon, as well as the displacement on Ajax carbon. The effect of the viscous flow in the macropore phase is not significant for the cases studied. The model accurately predicts the overshoot behavior and rollup of C2H6 during coadsorption. The prediction for the heavier compound C3H8 is always satisfactory, though at higher C3H8 mole fraction, the overshoot extent of C2H6 is overpredicted, possibly due to neglect of heat effects.

As trajet??rias do planejamento governamental no Brasil: meio s??culo de experi??ncias na administra????o p??blica

Este artigo tem como objetivo analisar o papel do Estado na formula????o do planejamento no Brasil a partir dos anos 30, per??odo que deu origem ??s primeiras iniciativas de planejamento, at?? os anos 80, momento em que se inicia a decad??ncia do planejamento governamental no pa??s. Optou-se por uma retrospectiva hist??rica que levantasse os principais aspectos inerentes ao planejamento como instrumento do desenvolvimento econ??mico deste per??odo, verificando as principais mudan??as ocorridas na sociedade. O artigo n??o pretende dar conta de todas as dimens??es e complexidades do tema nem esgotar o assunto, que ?? pol??mico e envolve muitas articula????es te??ricas com outras ??reas, como administra????o p??blica, economia e ci??ncia pol??tica. Desse modo, o artigo aponta na dire????o de que este balan??o de an??lises das experi??ncias de planejamento no Brasil demonstrou grandes avan??os econ??mico-financeiros e alguns fracassos de coordena????o e articula????o com outras esferas, como a executiva e a financeira. Assim, desde os anos 80, em detrimento da crise do Estado, o planejamento entra em decl??nio nas agendas governamentais, impossibilitado, por quest??es de ordem financeira, de realizar suas fun????es de racionaliza????o e efici??ncia econ??mica. Dessa forma, o Estado, nesse contexto, sempre representou, de forma geral, as diversas articula????es de interesses capitaneados pelo planejamento como instrumento de interven????o e controle social no Brasil.

Indicadores para diagn??stico, monitoramento e avalia????o de programas sociais no Brasil

O objetivo do texto ?? discutir as potencialidades e limita????es do uso das informa????es estat??sticas produzidas pelo IBGE e os registros administrativos de ??rg??os p??blicos para a constru????o de indicadores para diagn??stico, monitoramento e avalia????o de programas sociais no Brasil. Inicia-se com uma apresenta????o sobre os aspectos conceituais b??sicos acerca dos indicadores sociais, suas propriedades e formas de classifica????o. Depois, discute-se uma proposta de estrutura????o de um sistema de indicadores para subsidiar o processo de formula????o e avalia????o de pol??ticas e programas p??blicos no Pa??s. Conclui-se o texto advogando-se a necessidade de estruturar sistemas de indicadores que se ap??iem na busca de informa????es j?? existentes em fontes secund??rias e na produ????o de dados no ??mbito dos pr??prios programas.

Implementa????o e reformula????o de pol??ticas p??blicas: o caso do programa Cultura Viva

O presente artigo tem por objetivo demonstrar como um processo de implementa????o se modifica e ?? adaptado ao longo do tempo, podendo conduzir a um redesenho da pol??tica p??blica. Utiliza-se como estudo de caso o programa Cultura Viva. A pesquisa em que se baseia o artigo foi realizada por meio de entrevistas semiestruturadas com gestores do programa Cultura Viva e gestores de pontos de cultura, bem como por meio de um survey com os pontos de cultura do Estado de S??o Paulo e seus Munic??pios. Os resultados revelam que a implementa????o do programa alterou os crit??rios estabelecidos no processo de formula????o e incluiu novos instrumentos de gest??o, redesenhando assim a pol??tica p??blica

O plano plurianual: resultados da mais recente reforma do planejamento e or??amento no Brasil

O artigo visa apresentar o debate acerca das transforma????es oriundas da ??ltima reforma do planejamento e or??amento no Brasil, a qual introduziu o novo desenho do Plano Plurianual (PPA). Inicialmente, os princ??pios do modelo de or??amento por resultados ou desempenho que balizaram a formula????o do novo PPA s??o discutidos. Com base nos planos de gest??o das experi??ncias recentes do Plano e na proposta do pr??ximo PPA (2008-2011), s??o apresentadas as inova????es da configura????o do processo or??ament??rio no pa??s. Por fim, o artigo aborda os avan??os e restri????es da implementa????o do novo desenho do PPA e conclui que, apesar de formalmente institu??dos, os instrumentos do or??amento por resultados n??o atingem a finalidade prec??pua do modelo: melhoria da efetividade e efici??ncia nos gastos p??blicos.

Programa Bolsa Fam??lia: descentraliza????o, centraliza????o ou gest??o em redes?

O artigo analisa o processo de implementa????o e o modelo de gest??o do Programa Bolsa Fam??lia (PBF), no cerne do debate de centraliza????o-descentraliza????o. A hip??tese do estudo ?? que o PBF n??o apenas caminhou para o fortalecimento da descentraliza????o, superando alguns desafios da consolida????o do ???pacto federativo???, como tamb??m construiu uma configura????o mais complexa, pr??xima ?? gest??o em redes. Para tanto, ?? apresentada uma discuss??o te??rica acerca do federalismo, da descentraliza????o das pol??ticas sociais e do conceito de redes de pol??ticas p??blicas. Em seguida, s??o discernidos os princ??pios que fundamentaram a concep????o do programa, bem como as principais estrat??gias de implementa????o. Como conclus??o, argumenta-se que apesar de ainda persistirem desafios ?? gest??o compartilhada, a implementa????o do PBF se pautou n??o apenas no princ??pio da descentraliza????o, como tamb??m na transpar??ncia, controle e participa????o popular.

A Proposta de Acolhimento: sua formula????o e implementa????o nas unidades de aten????o prim??ria do Sistema ??nico de Sa??de no Munic??pio de Belo Horizonte

A proposta de acolhimento teve por objetivo garantir o acesso ??s Unidades de Aten????o Prim??ria do Sistema ??nico de Sa??de (SUS) em Belo Horizonte, Minas Gerais. Este trabalho analisa e tenta compreender a not??vel dist??ncia entre a proposi????o e a execu????o da proposta neste munic??pio. Usando contribui????es te??ricas do campo tem??tico das pol??ticas p??blicas na an??lise do contexto pol??tico-administrativo em que se desenvolveu a proposta, e utilizando as informa????es obtidas na pesquisa de campo com os principais idealizadores da proposta e alguns trabalhadores e usu??rios, foram identificadas, na sua formula????o e implanta????o, informa????es que ajudam a entender a dist??ncia observada.

Or??amento orientado a resultados: instrumento de fortalecimento democr??tico na Am??rica Latina?

O presente artigo discute a rela????o entre or??amento e democracia, argumentando que as transforma????es propugnadas pela or??amenta????o por resultados possuem n??o somente benef??cios gerenciais para a administra????o p??blica, mas tamb??m efeitos positivos sobre o sistema pol??tico e suas institui????es. Dados emp??ricos demonstram que os padr??es de confian??a institucional na Am??rica Latina s??o baixos, apesar de a confian??a no regime democr??tico ser significativamente maior. A implanta????o do modelo de or??amento orientado a resultados (OOR) representa ruptura com o paradigma tradicional de gest??o p??blica, propondo a substitui????o do foco nos insumos, controles, regulamentos e conformidade pela ??nfase na a????o estrat??gica, efetividade do gasto p??blico, flexibilidade gerencial, accountability e participa????o da sociedade. A formula????o de pol??ticas p??blicas orientadas para as necessidades dos cidad??os fomenta o capital social da comunidade, alavancando rela????es sin??rgicas entre governo e sociedade. Esse estreitamento fortalece as institui????es democr??ticas na medida em que favorece o monitoramento do desempenho do governante pela sua comunidade e, especialmente, contribui para aprimorar os mecanismos de representa????o pol??tica.

Perfil das condi????es de sa??de das capitais brasileiras na perspectiva dos Objetivos de Desenvolvimento do Mil??nio (ODM)

No contexto atual, o uso de indicadores sociais na avalia????o das pol??ticas p??blicas tem se tornado cada vez maior. Os indicadores sociais tamb??m t??m sido implementados no acompanhamento dos Objetivos de Desenvolvimento do Mil??nio (ODM), projeto da Organiza????o das Na????es Unidas (ONU) em que v??rios pa??ses, inclusive o Brasil, firmaram um pacto para tornar o mundo menos desigual. Sendo assim, para avaliar o cumprimento das metas estabelecidas nos ODM, este artigo pretende delinear perfis das capitais brasileiras quanto ??s condi????es de sa??de, sob a perspectiva dos ODM, a fim de contribuir para a formula????o e avalia????o de pol??ticas p??blicas e indicar um caminho para a escolha de indicadores importantes de serem monitorados. Foram delineados perfis, com a ado????o do m??todo Grade of Membership, quanto ?? sa??de nas capitais brasileiras. Perante os resultados obtidos, pode-se dizer que as condi????es de sa??de nas capitais brasileiras apresentam forte vi??s regional.