Optimization of Motor Performance

According to the OPTIMAL (Optimizing Performance Through Intrinsic Motivation and Attention of Learning) theory of motor learning, enhanced expectancies (EE), autonomy support (AS), and external focus (EF) augment the coupling of a person’s actions to intended movement goals. This goal-action coupling is postulated to boost a person’s focus on goal-related aspects of the motor task while reducing the person’s self-related thoughts, resulting in enhanced performance of skilled movements as well as in improving the acquisition outcomes for the learning of motor skills. The three studies in this compilation report were aimed at providing empirical evidence for the motor performance benefits of the combinatory implementation of the three key motivational (i.e., EE and AS) and attentional (i.e., EF) factors of the OPTIMAL theory. In addition, a preliminary investigation of the neuromechanistic influence of such an implementation on the human motor system was carried out. Using a between-participants design, the first study employed a maximal-effort countermovement jump task to examine the additive effects of the consecutive (or serial) implementation of EE, AS, and EF on motor performance. Results indicated that optimized group participants produced greater relative jump heights than control group participants. The second study used a within-participants design involving a clinical-applied balance test to determine the immediate effects of implementing EE, AS, and EF simultaneously (in parallel) on motor performance. The results showed that participants experienced greater postural stability in terms of making fewer balance errors and producing lower center-of-pressure velocity in the optimized condition than the control condition. Finally, a simple visuomotor task involving the rhythmic production of force via isometric finger abduction was used in the third study with a between-participants design. The neurophysiological and behavioral effects of a simultaneous implementation of EE, AS, and EF in relation to motor performance were examined using a novel TMS-force experimental protocol. The corticospinal excitability of all participants remained stable throughout the experiment. Additionally, the force-accuracy performance of participants in the optimized group was similar to that of participants in the control group

Individual Stock Investor Sentiment, Stock Issuance, and Financial Market Anomalies

There is an interaction effect between cross sectional variation in individual stock investor sentiment and a broad set of financial market anomalies. An average anomaly strategy earns higher (lower) 3-factor alpha conditioned on higher (lower) individual stock investor sentiment. This is mainly driven by the very negative alpha of the high sentiment conditioned short leg of each anomaly. Consequently, buying the low sentiment long leg of each anomaly and shorting the high sentiment short leg of each anomaly yields 0.434% to 0.474% more in monthly three-factor alpha than an unconditional anomaly strategy on average. In contrast, buying the high sentiment long leg of each anomaly and shorting the low sentiment short leg of each anomaly result in no alpha on average. I present novel evidence that the financial market anomalies are mispricings: firms act as arbitrageurs and tend to issue shares if they are in the short leg of an anomaly. In contrast, firms tend to repurchase shares and/or pay cash dividends if they are in the long leg of an anomaly. Individual stock investor sentiment exaggerates these effects. In particular, firms in the high sentiment short leg of anomalies trade equity ownership for cash or services (e.g. issuance of shares) while firms in the low sentiment long leg of anomalies pay or trade cash for equity ownership (e.g. cash dividends). The difference, measured using the Daniel and Titman (2006) composite issuance measure, is on average 0.535% to 0.632% per month. This is stronger than the unconditional effect by 0.132% to 0.351% per month

Understanding pathogenic and physiological T follicular helper cell formation

T follicular helper (Tfh) cells localize to follicles where they provide growth and selection signals to mutated germinal center (GC) B cells, thus promoting their differentiation into high affinity long-lived plasma cells and memory B cells. T-dependent B cell differentiation also occurs extrafollicularly, giving rise to unmutated plasma cells that are important for early protection against microbial infections. Bcl-6 expression in T cells has been shown to be essential for the formation of Tfh cells and GC B cells, but little is known about its requirement in physiological extrafollicular antibody responses. We use several mouse models in which extrafollicular plasma cells can be unequivocally distinguished from those of GC origin, combined with antigen-specific T and B cells, to show that the absence of T cell-expressed Bcl-6 significantly reduces T-dependent extrafollicular antibody responses. Bcl-6+ T cells appear at the T-B border soon after T cell priming and before GC formation, and these cells express low amounts of PD-1. Their appearance precedes that of Bcl-6+PD-1hi T cells, which are found within GC. IL-21 acts early to promote both follicular and extrafollicular antibody responses. In conclusion, Bcl6+ T cells are necessary at B cell priming in order to form extrafollicular antibody responses, and these pre-GC Tfh cells can be distinguished phenotypically from GC Tfh cells. Overactivity of the GC pathway due to accumulation of Tfh cells causes autoimmunity, underscoring the need to understand the factors that control Tfh homeostasis. Here, we have identified posttranscriptional repression of interferon-gamma (Ifng) mRNA as a novel mechanism to limit Tfh cell formation. Using the sanroque lupus model, we have shown that decreased Ifng mRNA decay caused excessive interferon-gamma signaling in T cells and led to accumulation of Tfh cells, spontaneous GC, autoantibody formation and nephritis. Unlike ICOS and T-bet deficiency that failed to rescue several autoimmune manifestations, interferon-gamma receptor deficiency completely prevented lupus development. Interferon-gamma blockade after disease onset reduced Tfh cells and autoantibodies, demonstrating that interferon-gamma overproduction was required to sustain lupus-associated pathology. Increased interferon-gamma signaling caused Bcl-6 overexpression in Tfh cells and their precursors. This novel link between interferon-gamma and aberrant Tfh formation provides a rationale for interferon-gamma blockade in lupus patients with an overactive Tfh cell-associated pathway

Illumination uniformity in endoscopic imaging

Standardised endoscopic digital images were taken and analysed using an image analysis software (National Instruments Vision Assistant version 7.1.1). The luminance plane was extracted and the pixel intensity distribution was determined along a horizontal line at the position of highest average intensity (centroid). The data was exported to MS Excel and the pixel intensity (y-axis) was plotted against pixel position (x-axis). A trendline using a 2nd order polynomial curve was fitted to each data set. The resultant equation for each curve was compared with equations obtained from other images taken under various illumination conditions and settings

A case study on application of the theory of planned behaviour: predicting physical activity of adolescents in Hong Kong

Objective: The aim of this case study was to predict the physical activity intention and behaviour of secondary school students in Hong Kong by applying the Ajzen’s Theory of Planned Behaviour (TPB) and past physical activity behaviour. Methods: 486 students (250 male and 236 female), ranging in age from 11 to 18 years, were enrolled in this study. By means of self-administrated questionnaire, demographic data, past physical activity and variables of theory of planned behaviour, such as attitude, subjective norm and perceived behavioural control were measured. Results: About 75% of students did not meet the standard of the physical activity recommended by government. Male had significantly higher behavioural intention than female. The variables of theory of planned behaviour explained 53.1% of physical activity intention with significant factors of subjective norm and perceived behavioural control (PBC), increasing to 56.2% with the addition of past physical activity behaviour. When predicting physical activity behaviour, theory of planned behaviour accounted for 26.6% of the variance. The prediction was further improved by including past physical activity behaviour. Conclusions: Results of this study give evidence that the theory of planned behaviour is a useful framework for prediction of physical activity intention of adolescents in Hong Kong. Among the variables, perceived behavioural control and past behaviour played a significant role in modelling the physical activity intention and behaviour of secondary school students

Gender Diversity And Firms’ Financial Performance In Malaysia

This study aims to investigate the relationship between gender diversity in a frm’s board of directors and fnancial performance of frms listed on Bursa Malaysia for the period between 2009 and 2013. Using unbalanced panel data analysis, we tested whether gender diversity in the boardroom may influence the frm’s performance, as measured by Tobin’s Q. We employed four different proxies for gender diversity (the dummy variable for women, the percentage of women on the board, the Blau index, and the Shannon index) to provide a more comprehensive measure of gender diversity. This study suggests that a higher degree of female representation on the board increases a frm’s fnancial performance. Positive discrimination favouring female boardroom appointment is therefore likely to persist as a feature of the corporate governance landscape in Malaysia