Comparison of the analytical performance of electrophoresis microchannels fabricated in PDMS, glass, and polyester-toner

This paper compares the analytical performance of microchannels fabricated in PDMS, glass, and polyester-toner for electrophoretic separations. Glass and PDMS chips were fabricated using well-established photolithographic and replica-molding procedures, respectively. PDMS channels were sealed against three different types of materials: native PDMS, plasma-oxidized PDMS, and glass. Polyester-toner chips were micromachined by a direct-printing process using an office laser printer. All microchannels were fabricated with similar dimensions according to the limitations of the direct-printing process (width/depth 150 mu m/12 mu m). LIF was employed for detection to rule out any losses in separation efficiency due to the detector configuration. Two fluorescent dyes, coumarin and fluorescein, were used as model analytes. Devices were evaluated for the following parameters related to electrophoretic separations: EOF, heat dissipation, injection reproducibility, separation efficiency, and adsorption to channel wall.

Incidências da hermenêutica para a metodologia da pesquisa teórica em psicanálise

O artigo traz uma breve revisão das principais abordagens hermenêuticas envolvidas na interpretação de textos e discursos a fim de delimitar a incidência dessa problemática no campo da pesquisa teórica em psicanálise. Define as diferentes formas de pesquisa em psicanálise e indica como as mudanças na compreensão da hermenêutica incidem também sobre a compreensão do estatuto epistemológico do saber psicanalítico. Apresenta e discute as propostas de metodologia de investigação teórica de Laplanche e Figueiredo. Ao concluir, indica a aproximação do método psicanalítico aplicado a textos e discursos com as perspectivas contemporâneas da hermenêutica e propõe uma abordagem própria para pesquisas de cunho histórico-conceitual e epistemológico em psicanálise.

A "reeducação" de adolescentes em uma comunidade terapêutica: o tratamento da drogadição em uma instituição religiosa

O abuso de drogas por adolescentes é, atualmente, um grave problema de saúde pública. Nessa área, a questão do tratamento destaca-se como um grande desafio, principalmente pelo fato de a maioria das intervenções não estar adaptada às especificidades desse público. Neste trabalho, serão apresentados os resultados de uma investigação que visou analisar o tratamento destinado a adolescentes em uma modalidade de atenção distinta das abordagens tradicionais da área da saúde: a comunidade terapêutica. Buscou-se compreender as concepções e práticas de atenção da instituição pesquisada, comparando-as com o prescrito pelas políticas públicas do setor. Os métodos utilizados foram a descrição etnográfica e a análise de conteúdo. Os resultados sugerem uma defasagem entre o prescrito pelas políticas públicas e a realidade da comunidade terapêutica pesquisada, a qual, apesar de proporcionar acolhimento às adolescentes, dificulta o desenvolvimento de suas singularidades e potencialidades devido à ênfase no "modelo moral" de tratamento da drogadição.

Análise proposicional quantitativa aplicada à pesquisa em administração

The analysis of interviews with open-ended questions is a common practice amongst researchers in the field of Management. The difficulty therein is to convert the linguistic data into categories or quantitative values for subsequent statistical treatment. Proposals made to this end generally entail counting lexical occurrences which, since they are founded on previously established meanings, fail to include semantic associations made by interviews. This article aims to present an analysis tool comprising a set of techniques apt to generate linguistic units that can be statistically described, compared, modeled and inferred: the Quantitative Propositional Analysis (QPA), Its main difference from other such methods lies in the choice of a proposition - and not the lexical unit - as analysis unit. We present the application of this method through a study about the international expansion of retail firms.

The International Collaboration on Air Pollution and Pregnancy Outcomes: Initial Results

BACKGROUND: The findings of prior studies of air pollution effects on adverse birth outcomes are difficult to synthesize because of differences in study design. OBJECTIVES: The International Collaboration on Air Pollution and Pregnancy Outcomes was formed to understand how differences in research methods contribute to variations in findings. We initiated a feasibility study to a) assess the ability of geographically diverse research groups to analyze their data sets using a common protocol and b) perform location-specific analyses of air pollution effects on birth weight using a standardized statistical approach. METHODS: Fourteen research groups from nine countries participated. We developed a protocol to estimate odds ratios (ORs) for the association between particulate matter <= 10 mu m in aerodynamic diameter (PM(10)) and low birth weight (LBW) among term births, adjusted first for socioeconomic status (SES) and second for additional location-specific variables. RESULTS: Among locations with data for the PM(10) analysis, ORs estimating the relative risk of term LBW associated with a 10-mu g/m(3) increase in average PM(10) concentration during pregnancy, adjusted for SES, ranged from 0.63 [95% confidence interval (CI), 0.30-1.35] for the Netherlands to 1.15 (95% CI, 0.61-2.18) for Vancouver, with six research groups reporting statistically significant adverse associations. We found evidence of statistically significant heterogeneity in estimated effects among locations. CONCLUSIONS: Variability in PM(10)-LBW relationships among study locations remained despite use of a common statistical approach. A more detailed meta-analysis and use of more complex protocols for future analysis may uncover reasons for heterogeneity across locations. However, our findings confirm the potential for a diverse group of researchers to analyze their data in a standardized way to improve understanding of air pollution effects on birth outcomes.

Doing Courts Justice? Studying Judicial Politics in Latin America

The past decade has brought an unprecedented boom in the study of courts as political actors in Latin America. We examine the extraordinary diversity of academic research on judicial politics in the region, identifying the key questions, findings, and theoretical debates in the literature, highlighting important conceptual disjunctions, and critiquing the research methods scholars of judicial politics in Latin America have employed in their work. We close by suggesting new avenues of inquiry to help advance the collective effort to understand the roles courts play in Latin American politics.

ADHD in a representative sample of the Brazilian population: estimated prevalence and comparative adequacy of criteria between adolescents and adults according to the item response theory

Background: Attention deficit hyperactivity disorder (ADHD) is a clinically significant disorder in adulthood, but current diagnostic criteria and instruments do not seem to adequately capture the complexity of the disorder in this developmental phase. Accordingly, there are limited data on the proportion of adults affected by the disorder, specially in developing countries. Method: We assessed a representative household sample of the Brazilian population for ADHD with the Adult ADHD Self-report Scale (ASRS) Screener, and evaluated the instrument according to the Rasch model of item response theory. Results: The sample was comprised by 3007 individuals, and the overal prevalence of positive screeners for ADHD was 5.8% [95% confidence interval (CI), 4.8-7.0]. Rasch analyses revealed the misfitt of the overall sample to expectations of the model. The evaluation of the sample stratified by age revealed that data for adolescents showed a signficant fittnes to the model expectations, while items completed by adults were not adequated. Conclusions: The lack of fitness to the model for adult respondents challenges the possibility of a linear transformation of the ordinal data into interval measures and the utilization of parametric analyses of data. This result suggests that diagnostic criteria and instruments for adult ADHD must take into account a developmental perspective. Moreover, it calls for further evaluation of currently employed research methods in light of modern theories of psychometrics. Copyright (C) 2010 John Wiley & Sons, Ltd.