Electrochimie analytique en absence d'electrolyte indiferent : transports de matiere lors de la reduction des acides a une ultramicroelectrode

O transporte de massa por migração relativo à redução do proton em um ultramicroeletrodo de platina foi investigado. O efeito da migração sobre as correntes limite foi primeiramente estudado para uma só espécie eletroativa em solução através da comparação dos voltampérogramas obtidos na ausência de eletrólito suporte assim como na presença de um grande excesso do mesmo (efeito do eletrólito). O comportamento do proton na água e dos ácidos do tipo BH+ e HA- em acetonitrila foi estudado e uma expressão para quantificar o efeito do eletrólito é proposta. Ela considera as condutâncias equivalentes e as cargas das espécies iônicas em solução, o número de elétrons envolvido na reação eletroquímica e o tipo de eletrodo utilisado. Os fenômenos de exaltação da corrente de migração que podem se manifestar quando a redução de uma espécie eletroativa é precedida pela redução de uma segunda espécie presente simultâneamente na solução foram igualmente estudados. Observa-se que a exaltação da corrente de migração de uma espécie iônica ocorre mesmo quando sua transformação eletroquímica precede aquela da espécie molecular. Nêste caso, se as mobilidades iônicas são próximas, a altura da onda da espécie molecular é duas vezes maior que na ausência da espécie iônica.

Making decisions in the absence of clear facts: a historical perspective

Recently, a claim has been made that executive decisions makers, far from being fact collectors, are actually fact users and integrators. As such, the claim continues, executive decision makers need help in understanding how to interpret facts, as well as guidance in making decisions in the absence of clear facts. This report justifies this claim against the backdrop of the modern history of decision making, from 1956 to the present. The historical excursion serves to amplify and clarify the claim, as well as to develop a theoretical framework for making decisions in the absence of clear facts. Two essential issues are identified that impact upon decision making in the absence of clear facts, as well criteria for decision making effectiveness under such circumstances. Methodological requirements and practical objectives round off the theoretical framework. The historical analysis enables the identification of one particular established methodology as claiming to meet the methodological requirements of the theoretical framework. Since the methodology has yet to be tried on information-poor situations, a further project is proposed that will test its validity.

Making decisions in the absence of clear facts

The effectiveness of a decision maker is not demonstrated through access to better or more information. Effectiveness is demonstrated in an ability to use, more resourcefully, whatever limited information is available, and to portray its implications more usefully. This paper demonstrates how decision makers can make systemic decisions in situations characterized by extremely limited information and, furthermore, what form such decisions take.

The influence of lifestyle and gender on sickness absence in brazilian workers

Background: Despite an increasing body of knowledge concerning gender and lifestyle factors as determinants of sickness absence in well-developed countries, the relationship between these variables has not been elucidated in emerging economic power countries, where the burden of non-communicable diseases is particularly high. This study aimed to analyze the relationships among lifestyle-related factors and sick leave and to examine whether gender differences in sickness absence can be explained by differences in socio-demographic, work and lifestyle-related factors among Brazilian workers. Methods: In this longitudinal study with a one year follow-up among 2.150 employees of a Brazilian airline company, sick leave was the primary outcome of interest. Independent variables collected by interview at enrolment in the study were gender, age, educational level, type of work, stress, and lifestyle-related factors (body mass index, physical activity and smoking). In addition, the risk for coronary heart disease was determined based on measurement of blood pressure, total cholesterol and glucose levels. The total number of days on sick leave during 12 months follow-up was available from the company register. Logistic regression analysis was used to determine the influence of socio-demographic, type of work and lifestyle-related factors on sick leave. Results: Younger employees, those with lower educational level, those who worked as air crew members and those with higher levels of stress were more likely to have sick leave. Body mass index and level of physical activity were not associated with sick leave. After adjustment by socio-demographic variables, increased odds for 10 or more days of sick leave were found in smokers (OR = 1.51, CI = 1.05-2.17), and ex-smokers (OR = 1.45, CI = 1.01-2.10). Women were more likely to have 10 or more days of sick leave. Gender differences were reduced mainly when adjusted for type of work (15%) and educational level (7%). Conclusions: The higher occurrence of sick leave among women than among men was partly explained by type of work and educational level. Our results suggest that type of work, a stressful life, and smoking are important targets for health promotion in this study population

Cartão de residente municipal: instrumento para aprimoramento da gestão no município: o caso de Louveira, SP

Para implementar políticas públicas nos municípios, um dos problemas é a ausência de dados que informem a realidade da situação local, o que evidencia o benefício e a necessidade dos instrumentos de tecnologia de informação para maior eficiência e eficácia na gestão pública. No município de Louveira, analisou-se o caso específico da implantação de uma ferramenta da tecnologia de informação que é utilizado por toda a prefeitura, denominado no local como Cartão Cidadão, que visa documentar o acesso e utilização dos serviços públicos municipais, porém no estudo do caso foi realizado um corte para averiguar o instrumento como estratégia de gestão para aprimorar o planejamento no município, mais precisamente na área da saúde. A gestão do sistema do Cartão Cidadão aliado aos registros em prontuário eletrônico de saúde deram maior confiabilidade ao banco de dados da saúde municipal, possibilitando averiguar e traçar estratégia definida para a gestão do Sistema Único de Saúde (SUS) local, assim como permitiu melhor averiguação dos desvios do sistema. Finalmente, apresentamos questionamentos sobre o sistema SUS frente a municipalização e ainda sobre e a questões do pacto de saúde e do próprio pacto federativo brasileiro.

Oxidation of acetylacetone catalyzed by horseradish peroxidase in the absence of hydrogen peroxide

Horseradish peroxidase (HRP) is a plant enzyme widely used in biotechnology, including antibody-directed enzyme prodrug therapy (ADEPT). Here, we showed that HRP is able to catalyze the autoxidation of acetylacetone in the absence of hydrogen peroxide. This autoxidation led to generation of methylglyoxal and reactive oxygen species. The production of superoxide anion was evidenced by the effect of superoxide dismutase and by the generation of oxyperoxidase during the enzyme turnover. The HRP has a high specificity for acetylacetone, since the similar beta-dicarbonyls dimedon and acetoacetate were not oxidized. As this enzyme prodrug combination was highly cytotoxic for neutrophils and only requires the presence of a non-human peroxidase and acetylacetone, it might immediately be applied to research on the ADEPT techniques. The acetylacetone could be a starting point for the design of new drugs applied in HRP-related ADEPT techniques. (c) 2006 Elsevier B.V. All rights reserved.

Absence of gluonic components in axial and tensor mesons

A quarkonium-gluonium mixing scheme previously developed to describe the characteristic of the pseudoscalar mesons is applied to axial and tensor mesons. The parameters of the model are determined by fitting the eigenvalues of a mass matrix. The corresponding eigenvectors give the proportion of light quarks, strange quarks and glueball in each meson. However, the predictions of the model for the branching ratios and electromagnetic decays are incompatible with the experimental results. These results suggest the absence of gluonic components in the states of axial and tensor isosinglet mesons analyzed here.

Absence of Klein's paradox for massive bosons coupled by nonminimal vector interactions

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Primary power distribution systems planning taking into account reliability, operation and expansion costs

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Absence of mutagenicity effects of Psidium cattleyanum Sabine (Myrtaceae) extract on peripheral blood and bone marrow cells of mice

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Spontaneous Periodontitis Development in Diabetic Rats Involves an Unrestricted Expression of Inflammatory Cytokines and Tissue Destructive Factors in the Absence of Major Changes in Commensal Oral Microbiota

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Absence of carcinogenic and anticarcinogenic effects of annatto in the rat liver medium-term assay

Annatto (Bixa orellana L.) is a natural food colorant extensively used in many processed foods, especially dairy products. The lower cost of production and the low toxicity, make annatto a very attractive and convenient pigment in substitution to the many synthetic colorants. In the present study we investigate the carcinogenic and anticarcinogenic effects of dietary annatto in Wistar rat liver using the preneoplastic glutathione S-transferase (GST-P) foci and DNA damage biomarkers. Annatto, containing 5% bixin, was administered in the diet at concentrations of 20, 200, and 1000 ppm (0.07; 0.80 and 4.23 bixin/kg body wt/day, respectively), continuously during 2 weeks before, or 8 weeks after DEN treatment (200 mg/kg body wt, i.p.), to evaluate its effect on the liver-carcinogenesis medium-term bioassay. The comet assay was used to investigate the modifying potential of annatto on DEN (20 mg/kg body wt)-induced DNA damage. The results showed that annatto was neither genotoxic nor carcinogenic at the highest concentration tested (1000 ppm). No protective effects were also observed in both GST-P foci development and comet assays. In conclusion, in such experimental conditions, annatto shows no hepatocarcinogenic effect or modifying potential against DEN-induced DNA damage and preneoplastic foci in the rat liver. (C) 2004 Elsevier Ltd. All rights reserved.