890 resultados para tip-timing


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One factor that research suggests impedes positive contact between outgroup members is the experience of anxiety that can occur when anticipating negative consequences of such interactions. Research examining attitudes and behaviour towards same-sex attracted individuals indicates that this intergroup anxiety is particularly evident when the anticipated interaction involves members of the same gender. The current studies investigate the effect of timing of disclosure of a person’s same-sex attractions in an effort to identify a means of reducing this anxiety. Study 1 uses a hypothetical scenario to gain insight into participants’ stated preferences for early or delayed knowledge of a person’s sexual orientation. Results reveal an association between experiencing close contact with gay individuals of the same gender in real life (but not opposite gender), and a preference for early disclosure. Results from an experimental study concur with these findings. After a face-to-face interaction task with a confederate of the same gender, participants sit further from the confederate for the late disclosure condition when compared with the early disclosure and no disclosure control. Future studies investigating the interaction between timing of disclosure of same-sex attractions and the intimacy of disclosure (casual vs. intimate), are discussed.

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Animals and plants in temperate regions must adapt their life cycle to pronounced seasonal variation. The research effort that has gone into studying these cyclical life history events, or phenological traits, has increased greatly in recent decades. As phenological traits are often correlated to temperature, they are relevant to study in terms of understanding the effect of short term environmental variation as well as long term climate change. Because of this, changes in phenology are the most obvious and among the most commonly reported responses to climate change. Moreover, phenological traits are important for fitness as they determine the biotic and abiotic environment an individual encounters. Fine-tuning of phenology allows for synchronisation at a local scale to mates, food resources and appropriate weather conditions. On a between-population scale, variation in phenology may reflect regional variation in climate. Such differences can not only give insights to life cycle adaptation, but also to how populations may respond to environmental change through time. This applies both on an ecological scale through phenotypic plasticity as well as an evolutionary scale through genetic adaptation. In this thesis I have used statistical and experimental methods to investigate both the larger geographical patterns as well as mechanisms of fine-tuning of phenology of several butterfly species. The main focus, however, is on the orange tip butterfly, Anthocharis cardamines, in Sweden and the United Kingdom. I show a contrasting effect of spring temperature and winter condition on spring phenology for three out of the five studied butterfly species. For A. cardamines there are population differences in traits responding to these environmental factors between and within Sweden and the UK that suggest adaptation to local environmental conditions. All populations show a strong negative plastic relationship between spring temperature and spring phenology, while the opposite is true for winter cold duration. Spring phenology is shifted earlier with increasing cold duration. The environmental variables show correlations, for example, during a warm year a short winter delays phenology while a warm spring speeds phenology up. Correlations between the environmental variables also occur through space, as the locations that have long winters also have cold springs. The combined effects of these two environmental variables cause a complex geographical pattern of phenology across the UK and Sweden. When predicting phenology with future climate change or interpreting larger geographical patterns one must therefore have a good enough understanding of how the phenology is controlled and take the relevant environmental factors in to account. In terms of the effect of phenological change, it should be discussed with regards to change in life cycle timing among interacting species. For example, the phenology of the host plants is important for A. cardamines fitness, and it is also the main determining factor for oviposition. In summary, this thesis shows that the broad geographical pattern of phenology of the butterflies is formed by counteracting environmental variables, but that there also are significant population differences that enable fine-tuning of phenology according to the seasonal progression and variation at the local scale.

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Os fundos de investimento mobiliários são uma boa alternativa para os aforradores diversificarem as suas poupanças, em particular que investem em ações. Esta classe de fundos visa proporcionar ao investidor o acesso a uma aplicação com uma elevada expectativa de rendibilidade a longo prazo. Dentro da oferta deste tipo de fundos domiciliados em Portugal, a questão fundamental é saber quais os mais apropriados para investir. Com este trabalho, pretende-se contribuir para o conhecimento da qualidade da gestão desta classe de ativos e, assim, fornecer mais elementos aos investidores para uma melhor tomada de decisão. Deste modo, esta investigação avalia as capacidades de timing e seletividade dos gestores de fundos de ações domiciliados em Portugal, em períodos de crise e não-crise, bem como os seus estilos de investimento. O estudo incide sobre o período de janeiro de 2000 a dezembro de 2014 e inclui todos os fundos, sobreviventes e não sobreviventes, que estiveram em atividade durante um período mínimo de 24 meses. Os resultados sugerem uma reduzida capacidade de timing e a inexistência de capacidades de seletividade por parte dos gestores. De um modo geral, as capacidades de seletividade são melhores nos períodos de não-crise do que nos períodos de crise, enquanto as capacidades de timing são, na maior parte dos casos, idênticas em diferentes estados do mercado. Em relação aos estilos de investimento, verifica-se uma maior predominância de ações com pequenas capitalizações nas carteiras, com maior incidência nos períodos de crise. Verifica-se, também, uma preferência dos gestores dos fundos que investem em Portugal e na Europa por ações de rendimento e uma preferência dos restantes gestores por ações de crescimento, sendo estas tendências mais vincadas em alturas de crise.

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This rejoinder reflects an important step, for me, in a preoccupation with methodology that has provided me with many hours of enjoyable reading, not to mention anxiety. For me the ‘reality’ of the incommensurable nature of paradigms and acceptance of the legitimacy of a range of conceptual and philosophical traditions came late. As a constructionist I find myself on the ‘anything goes’ end of methodology choice. This paper and my main paper ought not to be read as a critique of ‘middle range’ theory, but as a critique of an important and necessary aspect of the way we all seek to inscribe facts and structure our writing. What follows is a reflection of the influence Bruno Latour’s writings have had on my ways of seeing and perhaps an unhealthy emphasis on the small things that combine to produce convincing arguments and ‘facts’.

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We demonstrate a novel dual-wavelength erbium-fiber laser that uses a single nonlinear-optical loop mirror modulator to simultaneously modelock two cavities with chirped fiber Bragg gratings as end mirrors. We show that this configuration produces synchronized soliton pulse trains with an ultra-low RMS inter-pulse-stream timing jitter of 620 fs enabling application to multiwavelength systems at data rates in excess of 130 Gb/s.

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The tribology of linear tape storage system including Linear Tape Open (LTO) and Travan5 was investigated by combining X-ray Photoelectron Spectroscopy (XPS), Auger Electron Spectroscopy (AES), Optical Microscopy and Atomic Force Microscopy (AFM) technologies. The purpose of this study was to understand the tribology mechanism of linear tape systems then projected recording densities may be achieved in future systems. Water vapour pressure or Normalized Water Content (NWC) rather than the Relative Humidity (RH) values (as are used almost universally in this field) determined the extent of PTR and stain (if produced) in linear heads. Approximately linear dependencies were found for saturated PTR increasing with normalized water content increasing over the range studied using the same tape. Fe Stain (if produced) preferentially formed on the head surfaces at the lower water contents. The stain formation mechanism had been identified. Adhesive bond formation is a chemical process that is governed by temperature. Thus the higher the contact pressure, the higher the contact temperature in the interface of head and tape, was produced higher the probability of adhesive bond formation and the greater the amount of transferred material (stain). Water molecules at the interface saturate the surface bonds and makes adhesive junctions less likely. Tape polymeric binder formulation also has a significant role in stain formation, with the latest generation binders producing less transfer of material. This is almost certainly due to higher cohesive bonds within the body of the magnetic layer. TiC in the two-phase ceramic tape-bearing surface (AlTiC) was found to oxidise to form TiO2.The oxidation rate of TiC increased with water content increasing. The oxide was less dense than the underlying carbide; hence the interface between TiO2 oxide and TiC was stressed. Removals of the oxide phase results in the formation of three-body abrasive particles that were swept across the tape head, and gave rise to three-body abrasive wear, particularly in the pole regions. Hence, PTR and subsequent which signal loss and error growth. The lower contact pressure of the LTO system comparing with the Travan5 system ensures that fewer and smaller three-body abrasive particles were swept across the poles and insulator regions. Hence, lower contact pressure, as well as reducing stain in the same time significantly reduces PTR in the LTO system.

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The objective of this study was to test the hypothesis that the radial growth of lobes of the lichen Parmelia conspersa depends largely on growth processes which occur at the lobe tip. First, individual lobes were removed from thalli and portions of the lobe removed to within various distances from the tip. Radial growth of the lobe was unaffected until less than 2 mm of the lobe tip remained. Second, the surfaces of individual lobes were painted with acrylic paint leaving different portions of the lobe exposed. Painting lobes to within 0.5 mm and 1 mm of the tip substantially reduced radial growth. Third, the levels of ribitol, arabitol and mannitol were measured in different regions behind the lobe tip on four occasions during 1994. The concentration of the three carbohydrates was greatest at the lobe tip and the levels declined linearly with distance from the tip. Fourth, painting one vertical half of the lobe tip did not affect radial growth but artificially bisecting the lobe tip with a scalpel reduced radial growth. Although transport of carbohydrate from other regions of the lobe cannot be ruled out, the results support the hypothesis that radial growth in P. conspersa depends largely on processes within a region approximately 2 mm behind the lobe tip.

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This study examines whether the timing of adoption of the UK Statement of Standard Accounting Practice No. 20 'Foreign Currency Translation' depended on firms' financial characteristics. Consistent with US studies, we find that early adopters tended to be larger firms, and that variables, such as growth options, profitability, leverage and management payout, have strong predictive power. In general, the decision to adopt the Statement of Standard Accounting Practice No. 20 did not appear to adversely affect the profitability measures or dividend payout. Firms tended to adopt when the adverse economic consequences of the adoption were likely to be minimal. They also appeared to defer the adoption of the standard to influence their financial performance and, hence, to achieve certain corporate financial objectives. © 2006 AFAANZ.

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Sensorimotor synchronization is hypothesized to arise through two different processes, associated with continuous or discontinuous rhythmic movements. This study investigated synchronization of continuous and discontinuous movements to different pacing signals (auditory or visual), pacing interval (500, 650, 800, 950 ms) and across effectors (non-dominant vs. non-dominant hand). The results showed that mean and variability of asynchronization errors were consistently smaller for discontinuous movements compared to continuous movements. Furthermore, both movement types were timed more accurately with auditory pacing compared to visual pacing and were more accurate with the dominant hand. Shortening the pacing interval also improved sensorimotor synchronization accuracy in both continuous and discontinuous movements. These results show the dependency of temporal control of movements on the nature of the motor task, the type and rate of extrinsic sensory information as well as the efficiency of the motor actuators for sensory integration.

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Motor timing tasks have been employed in studies of neurodevelopmental disorders such as developmental dyslexia and ADHD, where they provide an index of temporal processing ability. Investigations of these disorders have used different stimulus parameters within the motor timing tasks which are likely to affect performance measures. Here we assessed the effect of auditory and visual pacing stimuli on synchronised motor timing performance and its relationship with cognitive and behavioural predictors that are commonly used in the diagnosis of these highly prevalent developmental disorders. Twenty- one children (mean age 9.6 years) completed a finger tapping task in two stimulus conditions, together with additional psychometric measures. As anticipated, synchronisation to the beat (ISI 329 ms) was less accurate in the visually paced condition. Decomposition of timing variance indicated that this effect resulted from differences in the way that visual and auditory paced tasks are processed by central timekeeping and associated peripheral implementation systems. The ability to utilise an efficient processing strategy on the visual task correlated with both reading and sustained attention skills. Dissociations between these patterns of relationship across task modality suggest that not all timing tasks are equivalent.

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We analyze detailed monthly data on U.S. open market stock repurchases (OMRs) that recently became available following stricter disclosure requirements. We find evidence that OMRs are timed to benefit non-selling shareholders. We present evidence that the profits to companies from timing repurchases are significantly related to ownership structure. Institutional ownership reduces companies' opportunities to repurchase stock at bargain prices. At low levels, insider ownership increases timing profits and at high levels it reduces them. Stock liquidity increases profits from timing OMRs.

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This study examines the selectivity and timing performance of 218 UK investment trusts over the period July 1981 to June 2009. We estimate the Treynor and Mazuy (1966) and Henriksson and Merton (1981) models augmented with the size, value, and momentum factors, either under the OLS method adjusted with the Newey-West procedure or under the GARCH(1,1)-in-mean method following the specification of Glosten et al. (1993; hereafter GJR-GARCH-M). We find that the OLS method provides little evidence in favour of the selectivity and timing ability, consistent with previous studies. Interestingly, the GJR-GARCH-M method reverses this result, showing some relatively strong evidence on favourable selectivity ability, particularly for international funds, as well as favourable timing ability, particularly for domestic funds. We conclude that the GJR-GARCH-M method performs better in evaluating fund performance compared with the OLS method and the non-parametric approach, as it essentially accounts for the time-varying characteristics of factor loadings and hence obtains more reliable results, in particular, when the high frequency data, such as the daily returns, are used in the analysis. Our results are robust to various in-sample and out-of-sample tests and have valuable implications for practitioners in making their asset allocation decisions across different fund styles. © 2012 Elsevier B.V.