Py-GC/MS(FID) assessed behavior of polysaccharides during kraft delignification of Eucalyptus globulus heartwood and sapwood

Eucalyptus globulus heartwood, sapwood and their delignified samples by kraft pulping at 130, 150 and 170 degrees C along time were characterized in respect to total carbohydrates by Py-GC/MS(FID). No significant differences between heartwood and sapwood were found in relation to pyrolysis products and composition. The main wood carbohydrate derived pyrolysis compounds were levoglucosan (25.1%), hydroxyacetaldehyde (12.5%), 2-oxo-propanal (10.3%) and acetic acid (8.7%). Levoglucosan decreased during the early stages of delignification and increased during the bulk and residual phases. Acetic acid decreased hydroxyacetaldehyde and 2-oxo-propanal increased, and 2-furaldehyde and hydroxypropanone remained almost constant during delignification. The C/L ratio was 3.2 in wood and remained rather constant in the first pulping periods until a loss of 15-25% in carbohydrate and 60% in lignin. Afterwards it increased sharply until 44 that correspond to the removal of 25-35% of carbohydrates and 95% of lignin. The pulping reactive selectivity to lignin vs. polysaccharides was the same for sapwood and heartwood. (C) 2013 Elsevier B.V. All rights reserved.

Measuring spatial interaction behavior in team sports using superimposed Voronoi diagrams

In team sports, the spatial distribution of players on the field is determined by the interaction behavior established at both player and team levels. The distribution patterns observed during a game emerge from specific technical and tactical methods adopted by the teams, and from individual, environmental and task constraints that influence players' behaviour. By understanding how specific patterns of spatial interaction are formed, one can characterize the behavior of the respective teams and players. Thus, in the present work we suggest a novel spatial method for describing teams' spatial interaction behaviour, which results from superimposing the Voronoi diagrams of two competing teams. We considered theoretical patterns of spatial distribution in a well-defined scenario (5 vs 4+ GK played in a field of 20x20m) in order to generate reference values of the variables derived from the superimposed Voronoi diagrams (SVD). These variables were tested in a formal application to empirical data collected from 19 Futsal trials with identical playing settings. Results suggest that it is possible to identify a number of characteristics that can be used to describe players' spatial behavior at different levels, namely the defensive methods adopted by the players.

Construção de um robô trepador com locomoção através de rodas e adesão através de meios magnéticos

Mestrado em Engenharia Electrotécnica e de Computadores

Synthesis, characterization, electrochemical behavior and in vitro protein tyrosine kinase inhibitory activity of the cymene-halogenobenzohydroxamato [Ru(eta(6)-cymene)(bha)Cl] complexes

The ruthenium(II)-cymene complexes [Ru(eta(6)-cymene)(bha)Cl] with substituted halogenobenzohydroxamato (bha) ligands (substituents = 4-F, 4-Cl, 4-Br, 2,4-F-2, 3,4-F-2, 2,5-F-2, 2,6-F-2) have been synthesized and characterized by elemental analysis, IR, H-1 NMR, C-13 NMR, cyclic voltammetry and controlled-potential electrolysis, and density functional theory (DFT) studies. The compositions of their frontier molecular orbitals (MOs) were established by DFT calculations, and the oxidation and reduction potentials are shown to follow the orders of the estimated vertical ionization potential and electron affinity, respectively. The electrochemical E-L Lever parameter is estimated for the first time for the various bha ligands, which can thus be ordered according to their electron-donor character. All complexes exhibit very strong protein tyrosine kinase (PTK) inhibitory activity, even much higher than that of genistein, the clinically used PTK inhibitory drug. The complex containing the 2,4-difluorobenzohydroxamato ligand is the most active one, and the dependences of the PTK activity of the complexes and of their redox potentials on the ring substituents are discussed. (C) 2012 Elsevier B.V. All rights reserved.

The effect of the angle of incidence on the aqueous corrosion of ion implanted M50 steel substrates

Following work on tantalum and chromium implanted flat M50 steel substrates, this work reports on the electrochemical behaviour of M50 steel implanted with tantalum and chromium and the effect of the angle of incidence. Proposed optimum doses for resistance to chloride attack were based on the interpretation of results obtained during long-term and accelerated electrochemical testing. After dose optimization from the corrosion viewpoint, substrates were implanted at different angles of incidence (15°, 30°, 45°, 60°, 75°, 90°) and their susceptibility to localized corrosion assessed using open-circuit measurements, step by step polarization and cyclic voltammetry at several scan rates (5–50 mV s-1). Results showed, for tantalum implanted samples, an ennoblement of the pitting potential of approximately 0.5 V for an angle of incidence of 90°. A retained dose of 5 × 1016 atoms cm-2 was found by depth profiling with Rutherford backscattering spectrometry. The retained dose decreases rapidly with angle of incidence. The breakdown potential varies roughly linearly with the angle of incidence up to 30° falling fast to reach -0.1 V (vs. a saturated calomel electrode (SCE)) for 15°. Chromium was found to behave differently. Maximum corrosion resistance was found for angles of 45°–60° according to current densities and breakdown potentials. Cr+ depth profiles ((p,γ) resonance broadening method), showed that retained doses up to an angle of 60° did not change much from the implanted dose at 90°, 2 × 1017 Cr atoms cm-2. The retained implantation dose for tantalum and chromium was found to follow a (cos θ)8/3 dependence where θ is the angle between the sample normal and the beam direction.

Opportunistic feeding behavior of Diplodus argenteus (Perciformes, Sparidae) : human-fish interaction in two rocky reefs from SE and S Brazil

Comportamento alimentar oportunista do marimbá Diplodus argenteus (Perciformes, Sparidae): interação humana-peixe em dois sistemas de costões rochosos do SE e SU do Brasil. Esse artigo aborda dois tipos de comportamentos alimentares do marimbá Diplodus argenteus em dois sistemas de costões rochosos do Atlântico sul no Brasil. Essa espécie alimentou-se sobre o fundo e exibiu comportamentos ocasionais e oportunísticos.

Computational analysis of quinoxalines N,N-Dioxide and ITS Derivates

A quinoxalina e seus derivativos são uma importante classe de compostos heterocíclicos, onde os elementos N, S e O substituem átomos de carbono no anel. A fórmula molecular da quinoxalina é C8H6N2, formada por dois anéis aromáticos, benzeno e pirazina. É rara em estado natural, mas a sua síntese é de fácil execução. Modificações na estrutura da quinoxalina proporcionam uma grande variedade de compostos e actividades, tais como actividades antimicrobiana, antiparasitária, antidiabética, antiproliferativa, anti-inflamatória, anticancerígena, antiglaucoma, antidepressiva apresentando antagonismo do receptor AMPA. Estes compostos também são importantes no campo industrial devido, por exemplo, ao seu poder na inibição da corrosão do metal. A química computacional, ramo natural da química teórica é um método bem desenvolvido, utilizado para representar estruturas moleculares, simulando o seu comportamento com as equações da física quântica e clássica. Existe no mercado uma grande variedade de ferramentas informaticas utilizadas na química computacional, que permitem o cálculo de energias, geometrias, frequências vibracionais, estados de transição, vias de reação, estados excitados e uma variedade de propriedades baseadas em várias funções de onda não correlacionadas e correlacionadas. Nesta medida, a sua aplicação ao estudo das quinoxalinas é importante para a determinação das suas características químicas, permitindo uma análise mais completa, em menos tempo, e com menos custos.

Metal deposition using Ionic liquids

There is an interest to create zinc/tin alloys to replace cadmium as a corrosion protective coating material. Existing aqueous electroplating systems for these alloys are commercially available but have several limitations. Dangerous and highly toxic complexing agents are uses e.g. cyanides. To overcome these problems, ionic liquids could provide a solution to obtain an alloy containing 20 to 30% of zinc. Ionic liquids (IL’s) often have wider electrochemical windows which allow the deposition of e.g. refractive metals that can not be deposited from aqueous solutions. In IL’s it is often not necessary to add complexing agents. The Zn/Sn alloy deposition from IL’s is therefore a promising application for the plating industry. Nevertheless, there are some issues with this alternative for aqueous systems. The degradation of the organic components, the control of the concentration of two metals and the risk of a two phase deposition instead of an alloy had to be overcome first. It is the main purpose of this thesis to obtain a Zn/Sn alloy with 20% zinc using IL’s as an electrolyte. First a separate study was performed on both the zinc and the tin deposition. Afterwards, an attempt to deposit a Zn/Sn alloy was made. An introduction to a study about the electrodeposition of refractive metals concludes this work. It initiated the research for oxygen-free IL’s to deposit molybdenum or tungsten. Several parameters (temperature, metal source and concentration, organic complexing agents,…) were optimized for both the zinc, tin and zinc/tin deposition. Experiments were performed both in a parallel plate cell and a Hull cell, so as to investigate the effect of current density as well. Ethaline200 was selected as electrolyte. As substrate, brass and iron were selected, while as anode a plate of the metal to deposit was chosen, tin for the alloy. The best efficiencies were always obtained on brass; however the iron substrate resulted in the best depositions. A concentration of 0.27M ZnCl2, 0.07M SnCl2 with 0.015M of K3-HEDTA as complexant resulted in a deposition containing the desired alloy with the amount of 20% zinc and 80% tin with good appearance. Refractory metals as molybdenum and tungsten cannot be electrodeposited from aqueous solutions without forming a co-deposition with Ni, Co or Fe. Here, IL’s could again provide a solution. A first requirement is the dissolution of a metal source. MoO3 could be suitable, however there are doubts about using oxides. Oxygen-free IL’s were sought for. A first attempt was the combination of ZnCl2 with chlormequat (CCC), which gave liquids below 150°C in molar ratios of 2 : 1 and 3 : 1. Unfortuna tely, MoO3 didn’t dissolve in these IL’s. Another route to design oxygen-free IL’s was the synthesis of quaternary ammonium salts. None of the methods used, proved viable as reaction time was long and resulted in very low yields. Therefore, no sufficient quantities were obtained to perform the possible electrochemical behavior of refractive metals.

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.

The Dark Side of Organizational Change: The Moderating Role of Political Behavior and Organizational Cynicism

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 of 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 aggression, although this is a research area where significant gaps occur and many issues were still not addressed Dupré and Barling (2006). According to Baron and Neuman (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 a moderating role of political behaviors and organizational cynicism (Ammeter et al., 2002, Ferris et al., 2002). The literature review suggests that mediators and moderators that intervene in the relationships between workplace aggression and its antecedents are understudied topics. James (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 and Broeck, 2009), a Workplace Aggression Scale (Vicente and D’Oliveira, 2008, 2009, 2010), an Organizational Cynicism Scale (Wanous, Reichers and Austin, 1994) and a Political Behavior Questionnaire (Yukl and Falbe, 1990). Participants representing a wide variety of jobs across many organizations were surveyed. The results 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.