743 resultados para Research performance


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We have utilised the combination of sensitivity and specificity afforded by coupling high-performance liquid chromatography (HPLC) to a tandem mass spectrometer (MS-MS) to produce an assay which is suitable for assaying glutathione (GSH) concentrations in liver tissue. The sensitivity suggests it may also be suitable for extrahepatic tissues, The method has been validated for GSH using mouse liver samples and also allows the assay of GSSG. The stability of GSH under conditions relevant to the assay has been determined. A 20-mul amount of a diluted methanol extract of tissue is injected with detection limits of 0.2 pmol for GSH and 2 pmol for GSSG. The HPLC uses an Altima C-18 (150X4.6 mm, 5 mum) column at 35 degreesC. Chromatography utilises a linear gradient from 0 to 10% methanol in 0.1% formic acid over 5 min, with a final isocratic stage holding at 10% methanol for 5 min. Total flow rate is 0.8 ml/min. The transition from the M+H ion (308.1 m/z for GSH, and 613.3 m/z for GSSG) to the 162.0 m/z (GSH) and 355.3 m/z (GSSG) fragments are monitored. (C) 2001 Elsevier Science B.V. All rights reserved.

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Carbon isotope composition (delta C-13), oxygen isotope composition (delta O-18), and nitrogen concentration (N-mass) of branchlet tissue at two canopy positions were assessed for glasshouse seedlings and 9-year-old hoop pine (Araucaria cunninghamii Ait. ex D. Don) trees from 22 open-pollinated families grown in 5 blocks of a progeny test at a water-limited and nitrogen-deficient site in southeastern Queensland, Australia. Significant variations in canopy delta C-13, delta O-18, and N-mass existed among the 9-year-old hoop pine families, with a heritability estimate of 0.72 for branchlet delta C-13 from the upper inner canopy position. There was significant variation in canopy delta C-13 of glasshouse seedlings between canopy positions and among the families, with a heritability estimate of 0.66. The canopy delta C-13 was positively related to canopy N-mass only for the upper outer crown in the field (R = 0.62, p < 0.001). Phenotypic correlations existed between tree height and canopy delta C-13 (R = 0.37-0.41, p < 0.001). Strong correlations were found between family canopy delta C-13 at this site and those at a wetter site and between field canopy delta C-13 and glasshouse seedling delta C-13. The mechanisms of the variation in canopy delta C-13 are discussed in relation to canopy photosynthetic capacity as reflected in the N-mass and stomatal conductance as indexed by canopy delta O-18.

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We report here a validated method for the quantification of a new immunosuppressant drug, everolimus (SDZ RAD), using HPLC-tandem mass spectrometry. Whole blood samples (500 mul) were prepared by protein precipitation, followed by C-18 solid-phase extraction. Mass spectrometric detection was by selected reaction monitoring with an electrospray interface operating in positive ionization mode. The assay was linear from 0.5 to 100 mug/l (r(2) > 0.996, n = 9). The analytical recovery and inter-day imprecision, determined using whole blood quality control samples (n = 5) at 0.5, 1.2, 20.0, and 75.0 mug/l, was 100.3-105.4% and less than or equal to7.6%, respectively. The assay had a mean relative recovery of 94.8 +/- 3.8%. Extracted samples were stable for up to 24 h. Fortified everolimus blood samples were stable at -80 degreesC for at least 8 months and everolimus was found to be stable in blood when taken through at least three freeze-thaw cycles. The reported method provides accurate, precise and specific measurement of everolimus in blood over a wide analytical range and is currently supporting phase 11 and III clinical trials. (C) 2002 Elsevier Science B.V. All rights reserved.

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At least 6% of primary school aged children present with DCD, where co-ordination is substantially below the normal range for the child’s age and intelligence. Motor skill difficulties negatively affect academic achievement, recreation and activities of daily living. Poor upper-limb co-ordination is a common difficulty for children with DCD. A possible cause of this problem is deviant muscle timing in proximal muscle groups, which results in poor postural and movement control. While studies have been published investigating postural control in response to external perturbations, detail about postural muscle activity during voluntary movement is limited even in children with normal motor development. No studies have investigated the relationship between muscle timing, resultant arm motion and upper-limb coordination deficits. Objectives: To investigate the relationship between functional difficulties with upper-limb motor skills and neuromuscular components of postural stability and coordination. Specifically, to investigate onset-timing of muscle activity, timing of arm movement, and resultant three-dimensional (3D) arm co-ordination during rapid, voluntary arm movement and to analyse differences arising due to the presence of DCD. This study is part of a larger research program investigating postural stability and control of upper limb movement in children. Design: A controlled, cross-sectional study of differences between children with and without DCD. Methods: This study included 50 children aged eight to 10 years (25 with DCD and 25 without DCD). Children participated in assessment of motor skills according to the Movement ABC Test and a laboratory study of rapid, voluntary arm movements. Parameters investigated included muscle activation timing of shoulder and trunk muscles (surface electromyography), arm movement timing (light sensor) and resultant 3D arm motion (Fastrak). Results: A MANOVA is being used to analyse between-group differences. Preliminary results indicate children with DCD demonstrate altered muscle timing during a rapid arm raise when compared with the control group of children. Conclusion: Differences in proximal muscle timing in children with DCD support the hypothesis that altered proximal muscle activity may contribute to poor proximal stability and consequently poor arm movement control. This has implications for clinical physiotherapy.

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The objective of this study was to investigate how seasonally fluctuating environmental conditions influence the diving performance of the highly aquatic, bimodally respiring turtle Rheodytes leukops in a natural setting. Over four consecutive seasons (Austral autumn 2000 to summer 2001), the diving behaviour of adult turtles was recorded via pressure-sensitive time-depth recorders within Marlborough Creek, central Queensland, Australia. Short surfacing intervals recorded for R. leukops in winter suggest that the species utilizes aquatic respiration as an overwintering strategy to prevent the development of a metabolic acidosis during the long inactive dives observed during the season. As water temperature increases and aquatic P-O 2 decreases, R. leukops switches from facultative to obligate air-breathing, presumably because of the increased metabolic cost associated with aquatic respiration under summer conditions. Increases in mean surfacing time from winter to spring and summer are attributed to seasonal changes in behaviour possibly associated with foraging rather than to the physiological state of the turtle, given that no difference in median surfacing time among seasons was observed.

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In many respects, Australian boards more closely approach normative best practice guidelines for corporate governance than boards in other Western countries. Do Australian firms then demonstrate a board demographic-organisational performance link that has not been found in other economies? We examine the relationships between board demographics and corporate performance in 348 of Australia's largest publicly listed companies and describe the attributes of these firms and their boards. We find that, after controlling for firm size, board size is positively correlated with firm value. We also find a positive relationship between the proportion of inside directors and the market-based measure of firm performance. We discuss the implications of these findings and compare our findings to prevailing research in the US and the UK.

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In spite of their wide application in comminution circuits, hydrocyclones have at least one significant disadvantage in that their operation inherently tends to return the fine denser liberated minerals to the grinding mill. This results in unnecessary overgrinding which adds to the milling cost and can adversely affect the efficiency of downstream processes. In an attempt to solve this problem, a three-product cyclone has been developed at the Julius Kruttschnitt Mineral Research Centre (JKMRC) to generate a second overflow in which the fine dense liberated minerals can be selectively concentrated for further treatment. In this paper, the design and operation of the three-product cyclone are described. The influence of the length of the second vortex finder on the performance of a 150-mm unit treating a mixture of magnetite and silica is investigated. Conventional cyclone tests were also conducted under similar conditions. Using the operational performance data of the three-product and conventional cyclones, it is shown that by optimising the length of the second vortex finder, the amount of fine dense mineral particles that reports to the three-product cyclone underflow can be reduced. In addition, the three-product cyclone can be used to generate middlings stream that may be more suitable for flash flotation than the conventional cyclone underflow, or alternatively, could be classified with a microscreen to separate the valuables from the gangue. At the same time, a fines stream having similar properties to those of the conventional overflow can be obtained. Hence, if the middlings stream was used as feed for flash flotation or microscreening, the fines stream could be used in lieu of the conventional overflow without compromising the feed requirements for the conventional flotation circuit. Some of the other potential applications of the new cyclone are described. (C) 2003 Elsevier Science B.V. All rights reserved.

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As end-user computing becomes more pervasive, an organization's success increasingly depends on the ability of end-users, usually in managerial positions, to extract appropriate data from both internal and external sources. Many of these data sources include or are derived from the organization's accounting information systems. Managerial end-users with different personal characteristics and approaches are likely to compose queries of differing levels of accuracy when searching the data contained within these accounting information systems. This research investigates how cognitive style elements of personality influence managerial end-user performance in database querying tasks. A laboratory experiment was conducted in which participants generated queries to retrieve information from an accounting information system to satisfy typical information requirements. The experiment investigated the influence of personality on the accuracy of queries of varying degrees of complexity. Relying on the Myers–Briggs personality instrument, results show that perceiving individuals (as opposed to judging individuals) who rely on intuition (as opposed to sensing) composed queries more accurately. As expected, query complexity and academic performance also explain the success of data extraction tasks.

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Blast fragmentation can have a significant impact on the profitability of a mine. An optimum run of mine (ROM) size distribution is required to maximise the performance of downstream processes. If this fragmentation size distribution can be modelled and controlled, the operation will have made a significant advancement towards improving its performance. Blast fragmentation modelling is an important step in Mine to Mill™ optimisation. It allows the estimation of blast fragmentation distributions for a number of different rock mass, blast geometry, and explosive parameters. These distributions can then be modelled in downstream mining and milling processes to determine the optimum blast design. When a blast hole is detonated rock breakage occurs in two different stress regions - compressive and tensile. In the-first region, compressive stress waves form a 'crushed zone' directly adjacent to the blast hole. The second region, termed the 'cracked zone', occurs outside the crush one. The widely used Kuz-Ram model does not recognise these two blast regions. In the Kuz-Ram model the mean fragment size from the blast is approximated and is then used to estimate the remaining size distribution. Experience has shown that this model predicts the coarse end reasonably accurately, but it can significantly underestimate the amount of fines generated. As part of the Australian Mineral Industries Research Association (AMIRA) P483A Mine to Mill™ project, the Two-Component Model (TCM) and Crush Zone Model (CZM), developed by the Julius Kruttschnitt Mineral Research Centre (JKMRC), were compared and evaluated to measured ROM fragmentation distributions. An important criteria for this comparison was the variation of model results from measured ROM in the-fine to intermediate section (1-100 mm) of the fragmentation curve. This region of the distribution is important for Mine to Mill™ optimisation. The comparison of modelled and Split ROM fragmentation distributions has been conducted in harder ores (UCS greater than 80 MPa). Further work involves modelling softer ores. The comparisons will be continued with future site surveys to increase confidence in the comparison of the CZM and TCM to Split results. Stochastic fragmentation modelling will then be conducted to take into account variation of input parameters. A window of possible fragmentation distributions can be compared to those obtained by Split . Following this work, an improved fragmentation model will be developed in response to these findings.

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O design possui um papel central nos negócios, participando de forma crucial no intercambio cultural e econômico da sociedade. Uma das competências do profissional de design gráfico é o desenvolvimento da Identidade Visual Corporativa (IVC). Ela tem como função definir visualmente o perfil de uma empresa, configurando-se, assim, como um composto mercadológico de fundamental importância para diferenciação das organizações, possuindo um importante papel para o crescimento das micro e pequenas empresas (MPEs). O objetivo desta pesquisa é verificar de que forma os gestores de MPEs percebem a atuação do design gráfico sobre a performance do seu negócio, avaliada a partir da sua experiência com a IVC desenvolvida por um profissional de design e aplicada pela empresa em suas atividades. A pesquisa é aplicada, em relação a sua finalidade, e exploratória, quanto ao seu objetivo. Sua condução se deu a partir de pesquisa bibliográfica, entrevista semiestruturada com os gestores das MPEs investigadas e pesquisa documental em materiais fornecidos pelos sujeitos da pesquisa, realizando-se, desta forma, uma triangulação metodológica a fim de contribuir para o exame do fenômeno. Como estratégia de investigação foi utilizado o estudo de casos múltiplos, realizado com 7 (sete) MPEs que haviam incorporado sua IVC há pelo menos 2 (dois) anos, dos setores de comércio e serviço, localizadas nos municípios de Vitória, Vila Velha, Serra ou Cariacica. Os dados coletados foram analisados por meio da Análise de Conteúdo, com base nas etapas descritas por Bardin (1977) e Laville (1999), distribuindo as unidades de análise (frases e parágrafos) nas categorias desenvolvidas: Motivação, Integração da IVC, Gestão da IVC, Relevância da IVC, IVC e Performance e Expressão Visual. A análise utilizou a abordagem quantitativa, realizada por meio da técnica de percentagem, e qualitativa, com maior ênfase na última, onde foram analisadas as categorias e seus elementos, assim como as relações entre elas, buscando extrair os significados construídos. Desta forma, foi possível verificar que a maior parte dos gestores das MPEs investigadas identificam que o design gráfico, por meio da IVC, contribui de forma positiva para a performance do seu negócio, proporcionando diferentes tipos de benefícios, dentre os mais citados foram: Identificação/Reconhecimento, Fortalecimento (solidez, estabilidade, profissionalismo), Novos Clientes, Imagem, Receptividade, Agregação de Valor para a Marca e Diferenciação.

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O design possui um papel central nos negócios, participando de forma crucial no intercambio cultural e econômico da sociedade. Uma das competências do profissional de design gráfico é o desenvolvimento da Identidade Visual Corporativa (IVC). Ela tem como função definir visualmente o perfil de uma empresa, configurando-se, assim, como um composto mercadológico de fundamental importância para diferenciação das organizações, possuindo um importante papel para o crescimento das micro e pequenas empresas (MPEs). O objetivo desta pesquisa é verificar de que forma os gestores de MPEs percebem a atuação do design gráfico sobre a performance do seu negócio, avaliada a partir da sua experiência com a IVC desenvolvida por um profissional de design e aplicada pela empresa em suas atividades. A pesquisa é aplicada, em relação a sua finalidade, e exploratória, quanto ao seu objetivo. Sua condução se deu a partir de pesquisa bibliográfica, entrevista semiestruturada com os gestores das MPEs investigadas e pesquisa documental em materiais fornecidos pelos sujeitos da pesquisa, realizando-se, desta forma, uma triangulação metodológica a fim de contribuir para o exame do fenômeno. Como estratégia de investigação foi utilizado o estudo de casos múltiplos, realizado com 7 (sete) MPEs que haviam incorporado sua IVC há pelo menos 2 (dois) anos, dos setores de comércio e serviço, localizadas nos municípios de Vitória, Vila Velha, Serra ou Cariacica. Os dados coletados foram analisados por meio da Análise de Conteúdo, com base nas etapas descritas por Bardin (1977) e Laville (1999), distribuindo as unidades de análise (frases e parágrafos) nas categorias desenvolvidas: Motivação, Integração da IVC, Gestão da IVC, Relevância da IVC, IVC e Performance e Expressão Visual. A análise utilizou a abordagem quantitativa, realizada por meio da técnica de percentagem, e qualitativa, com maior ênfase na última, onde foram analisadas as categorias e seus elementos, assim como as relações entre elas, buscando extrair os significados construídos. Desta forma, foi possível verificar que a maior parte dos gestores das MPEs investigadas identificam que o design gráfico, por meio da IVC, contribui de forma positiva para a performance do seu negócio, proporcionando diferentes tipos de benefícios, dentre os mais citados foram: Identificação/Reconhecimento, Fortalecimento (solidez, estabilidade, profissionalismo), Novos Clientes, Imagem, Receptividade, Agregação de Valor para a Marca e Diferenciação.

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This paper analyses the performance and investment styles of internationally oriented Socially Responsible Investment (SRI)funds, domiciled in eight European markets, in comparison with characteristics-matched conventional funds. To the best of our knowledge, this is the first multi-country study, focused on international SRI funds (investing in Global and in European equities), to combine the matched-pairs approach with the use of robust conditional multi-factor performance evaluation models, which allow for both time-varying alphas and betas and also control for home biases and spurious regression biases.In general, the results show that differences in the performance of international SRI funds and their conventional peers are not statistically significant. Regarding investment styles, SRI and conventional funds exhibit similar factor exposures in most cases. In addition,conventional benchmarks present a higher explaining power of SRI fund returns than SRI benchmarks. Our results also show significant differences in the investment styles of SRI funds according to whether they use “best-in-class” screening strategies or not. When compared to SRI funds that employ simple negative and/or positive screens, SRI “best-in-class” funds present significantly lower exposures to small caps and momentum strategies and significantly higher exposures to local stocks.

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Purpose – this paper has two main purposes: (1)explore if government agencies more oriented to NPM postulates are more willing to use PM practices and to improve their performance; and (2) investigate whether the fit between the use of PM practices and the organizationa performance is dependent upon from the capacity of agencies to adapt its structures to changes introduced by NPM reforms. Design/methodology/approach - this paper is based on the survey method and provides empirical evidence from Portuguese government agencies.Findings (mandatory) - Our findings suggest that government agencies that made structural arrangements under the NPM reforms are more willing to use PM practices and will perform better than other agencies. In addition, this paper show that therelationship between the use of PM practices and the organizational performance is dependent upon from the agencies capacity to adopt new structural arrangements under the NPM reforms.Practical implications – this paper has three main contributions: (1) contribute to knowledge about the relationship between the introduction of NPM changes in the use of PM practices; (2) contribute to clarify whether agencies more oriented to NPM postulates are improving performance; and (3) help to clarify the way the organizations should adapt their structures for to be more effective in the use of PM practices. Originality/value - The quantitative empirical research, based on the unique survey applied to Portuguese government agencies on this field, allow us to add to prior research mainly based on case studies and oriented to local governments (Budding, 2004).