Static and hydrodynamic monitoring of citalopram based on its electro-oxidation behavior at a glassy-carbon surface

The electrooxidative behavior of citalopram (CTL) in aqueous media was studied by cyclic voltammetry (CV) and square-wave voltammetry (SWV) at a glassy-carbon electrode. The electrochemical behaviour of CTL involves two electrons and two protons in the irreversible and diffusion controlled oxidation of the tertiary amine group. The maximum analytical signal was obtained in a phosphate buffer (pH ¼ 8.2). For analytical purposes, an SWV method and a flow-injection analysis (FIA) system with amperometric detection were developed. The optimised SWV method showed a linear range between 1.10 10 5–1.20 10 4 molL 1, with a limit of detection (LOD) of 9.5 10 6 molL 1. Using the FIA method, a linear range between 2.00 10 6–9.00 10 5 molL 1 and an LODof 1.9 10 6 molL 1 were obtained. The validation of both methods revealed good performance characteristics confirming applicability for the quantification of CTL in several pharmaceutical products.

Validação da versão brasileira do Youth Risk Behavior Survey 2007

OBJETIVO: Validar as propriedades psicométricas da versão brasileira do questionário Youth Risk Behavior Survey (YRBS), versão 2007. MÉTODOS: Foram realizadas tradução para o português da versão original do YRBS2007 e retrotradução para o inglês. As versões do questionário foram analisadas por comitê de juízes. O comitê utilizou como critério de análise as equivalências semântica, idiomática, cultural e conceitual. Para identificação das propriedades psicométricas, a versão final do questionário YRBS2007 traduzida foi administrada em duas ocasiões com intervalo de duas semanas em amostra de 873 estudantes de ambos os sexos, do ensino médio, em Londrina, PR, em 2007. A confiabilidade teste-reteste foi analisada pelo cálculo do índice de concordância Kappa e da taxa de prevalência de cada comportamento de risco nas réplicas de aplicação. Teste de qui-quadrado foi empregado para identificar diferenças estatísticas entre a primeira e a segunda aplicações do questionário. RESULTADOS: Após discretas modificações apontadas nos processos de tradução, o comitê de juízes considerou que a versão para o idioma português do YRBS2007 apresentou equivalências semântica, idiomática, cultural e conceitual. Diferenças significativas entre as taxas de prevalências de ambas as aplicações foram observadas em 23,4% dos itens. A identificação de 91% dos itens com índice de concordância Kappa entre moderado a substancial e valor médio desse índice de 68,6% indicou a qualidade das propriedades psicométricas do YRBS2007 traduzido para o idioma português. CONCLUSÕES: A tradução, a adaptação transcultural e as qualidades psicométricas do questionário YRBS2007 foram satisfatórias, o que viabiliza sua aplicação em estudos epidemiológicos no Brasil.

Adsorption behavior of α-cypermethrin on cork and activated carbon

Studies were undertaken to determine the adsorption behavior of α-cypermethrin [R)-α-cyano-3-phenoxybenzyl(1S)-cis- 3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylate, and (S)-α-cyano-3-phenoxybenzyl (1R)-cis-3-(2,2-dichlorovinyl)-2,2- dimethylcyclopropanecarboxylate] in solutions on granules of cork and activated carbon (GAC). The adsorption studies were carried out using a batch equilibrium technique. A gas chromatograph with an electron capture detector (GC-ECD) was used to analyze α-cypermethrin after solid phase extraction with C18 disks. Physical properties including real density, pore volume, surface area and pore diameter of cork were evaluated by mercury porosimetry. Characterization of cork particles showed variations thereby indicating the highly heterogeneous structure of the material. The average surface area of cork particles was lower than that of GAC. Kinetics adsorption studies allowed the determination of the equilibrium time—24 hours for both cork (1–2 mm and 3–4 mm) and GAC. For the studied α-cypermethrin concentration range, GAC revealed to be a better sorbent. However, adsorption parameters for equilibrium concentrations, obtained through the Langmuir and Freundlich models, showed that granulated cork 1–2 mm have the maximum amount of adsorbed α-cypermethrin (qm) (303 μg/g); followed by GAC (186 μg/g) and cork 3-4 mm (136 μg/g). The standard deviation (SD) values, demonstrate that Freundlich model better describes the α-cypermethrin adsorption phenomena on GAC, while α-cypermethrin adsorption on cork (1-2 mm and 3-4 mm) is better described by the Langmuir. In view of the adsorption results obtained in this study it appears that granulated cork may be a better and a cheaper alternative to GAC for removing α-cypermethrin from water.

Health-related behavior and quality of life among the elderly: a population-based study

OBJECTIVE: To assess the association between health-related behaviors and quality of life among the elderly. METHODS: A population-based cross-sectional study was carried out including 1,958 elderly living in four areas in the state of São Paulo, southeastern Brazil, 2001/2002. Quality of life was assessed using the Medical Outcomes Study SF-36-Item Short Form Health Survey instrument. This instrument's eight subscales and two components were the dependent variables. Independent variables were physical activity, weekly frequency of alcohol consumption and smoking. Multiple linear regression models were used to control for the effect of gender, age, schooling, work, area of residence and number of chronic conditions. RESULTS: Physical activity was positively associated with the eight SF-36 subscales. The stronger associations were found for role-physical (β=11.9), physical functioning (β=11.3) and physical component. Elderly individuals who consumed alcohol at least once a week showed a better quality of life than those did not consume alcohol. Compared to non-smokers, smokers had a poorer quality of life for the mental component (β=-2.4). CONCLUSIONS: The study results showed that physical activity, moderate alcohol consumption and no smoking are positively associated with a better quality of life in the elderly.

Buying behavior and competition in the software market

In the actual world, the impact of the software buying decisions has a rising relevance in social and economic terms. This research tries to explain it focusing on the organizations buying decisions of Operating Systems and Office Suites for personal computers and the impact on the competition between incumbent and alternative players in the market in these software categories, although the research hypotheses and conclusions may extend to other software categories and platforms. We concluded that in this market beside brand image, product features or price, other factors could have influence in the buying choices. Network effect, switching costs, local network effect, lock-in or consumer heterogeneity all have influence in the buying decision, protecting the incumbent and making it difficult for the competitive alternatives, based mainly on product features and price, to gain market share to the incumbent. This happens in a stronger way in the Operating Systems category.

Influencing factors on the buying behavior in the software market

The case of desktop Operating System and Office Suite choices considering Proprietary and Open Source Software alternatives.

Workplace aggression in organizational changing processes: The mediation role of leader political (soft and hard) behavior

One of the main trends in workplace aggression research is studying its antecedents. But the literature also reveals that some predictors remain understudied, like organizational change [1]. Additionally, possible mediators of this relationship were not investigated. The main objective of this research is studding the mediating effect of the leader political behavior (soft and hard version) on the relationship between organizational change and workplace aggression. Participants representing a wide variety of jobs across many organizations were surveyed. The measures used in this research are an Organizational Change Questionnaire climate of change, processes, and readiness [2], a Workplace Aggression Scale [e.g. 3, 4] and a Political Behavior Questionnaire [5]. The results of the study and its theoretical and practical implications will be presented and discussed.

Agressão no trabalho em processos de mudança organizacional: O papel mediador do cinismo organizacional e do comportamento político

Workplace aggression is a factor that shapes the interaction between individuals and their work environment and produces many undesirable outcomes, sometimes introducing heavy costs for organizations. Only through a comprehensive understanding o f the genesis of workplace aggression is possible to develop strategies and interventions to minimize its nefarious effects. The existent body of knowledge has already identified several individual, situational and contextual antecedents of workplace aggr ession, although this is a research area where significant gaps occur and many issues were still not addressed (Dupré & Barling, 2006). According to Neuman and Baron (1998) one of these predictors is organizational change, since certain changes in the work environment (e.g., changes in management) can lead to increased aggression. This paper intends to contribute to workplace aggression research by studying its relationship with organizational change, considering the mediation role of political behaviors an d organizational cynicism (Ammeter, Douglas, Gardner, Hochwarter, & Ferris, 2002). The literature review suggests that mediators and moderators that intervene in the relationships between workplace aggression and its antecedents are understudied topics. Ja mes (2005) sustains that organizational politics is related to cynicism and the empirical research of Miranda (2008) has identified leadership political behavior as an antecedent of cynicism but these two variables were not yet investigated regarding their relationship with workplace aggression. This investigation was operationalized using several scales including the Organizational Change Questionnaire - climate of change, processes, and readiness (Bouckenooghe, Devos, & Broeck, 2009), a Workplace Aggressio n Scale (Vicente, 2008, 2009), an Organizational Cynicism Scale (Wanous, Reichers, & Austin, 1994) and a Political Behavior Questionnaire (Yukl & Falbe, 1990). Participants representing a wide variety of jobs across many organizations were surveyed. The r esults of the study and its implications will be presented and discussed. This study contribution is also discussed in what concerns organizational change practices in organizations.

Os millennials em Portugal: estudo exploratório a partir de um coorte etário sobre engagement consumidor-marca

Dissertação apresentada à Escola Superior de Comunicação Social como parte dos requisitos para obtenção de grau de mestre em Publicidade e Marketing.

Parallel real-time support for distributed adaptive embedded applications

Real-time embedded applications require to process large amounts of data within small time windows. Parallelize and distribute workloads adaptively is suitable solution for computational demanding applications. The purpose of the Parallel Real-Time Framework for distributed adaptive embedded systems is to guarantee local and distributed processing of real-time applications. This work identifies some promising research directions for parallel/distributed real-time embedded applications.

Service offloading in adaptive real-time systems

Smartphones and other internet enabled devices are now common on our everyday life, thus unsurprisingly a current trend is to adapt desktop PC applications to execute on them. However, since most of these applications have quality of service (QoS) requirements, their execution on resource-constrained mobile devices presents several challenges. One solution to support more stringent applications is to offload some of the applications’ services to surrogate devices nearby. Therefore, in this paper, we propose an adaptable offloading mechanism which takes into account the QoS requirements of the application being executed (particularly its real-time requirements), whilst allowing offloading services to several surrogate nodes. We also present how the proposed computing model can be implemented in an Android environment

Risk Analysis and Behavior of Electricity Portfolio Aggregator

The scope of this paper is to adapt the standard mean-variance model of Henry Markowitz theory, creating a simulation tool to find the optimal configuration of the portfolio aggregator, calculate its profitability and risk. Currently, there is a deep discussion going on among the power system society about the structure and architecture of the future electric system. In this environment, policy makers and electric utilities find new approaches to access the electricity market; this configures new challenging positions in order to find innovative strategies and methodologies. Decentralized power generation is gaining relevance in liberalized markets, and small and medium size electricity consumers are also become producers (“prosumers”). In this scenario an electric aggregator is an entity that joins a group of electric clients, customers, producers, “prosumers” together as a single purchasing unit to negotiate the purchase and sale of electricity. The aggregator conducts research on electricity prices, contract terms and conditions in order to promote better energy prices for their clients and allows small and medium customers to benefit improved market prices.

Hybrid adaptive control of a dragonfly model

Dragonflies show unique and superior flight performances than most of other insect species and birds. They are equipped with two pairs of independently controlled wings granting an unmatchable flying performance and robustness. In this paper, it is presented an adaptive scheme controlling a nonlinear model inspired in a dragonfly-like robot. It is proposed a hybrid adaptive (HA) law for adjusting the parameters analyzing the tracking error. At the current stage of the project it is considered essential the development of computational simulation models based in the dynamics to test whether strategies or algorithms of control, parts of the system (such as different wing configurations, tail) as well as the complete system. The performance analysis proves the superiority of the HA law over the direct adaptive (DA) method in terms of faster and improved tracking and parameter convergence.

Liderança transformacional/transacional: que impacto no cinismo organizacional?

Dissertação apresentada à Escola Superior de Comunicação Social como parte dos requisitos para obtenção de grau de mestre em Gestão Estratégica das Relações Públicas.

Kinetic behavior of Desulfovibrio gigas aldehyde oxidoreductase encapsulated in reverse micelles

Biochemical and Biophysical Research Communications 308 (2003) 73–78