Psychomotor speed is related to perceived performance in rowers

The goal of the present study was to determine if psychomotor speed is related to perceived performance. It was hypothesized that lower perceived performance was related to longer reaction times. A total of 85 measurements were taken in 26 varsity rowers (mean age 21.3 years, s=1.6) on five occasions over the course of the season. Perceived performance was measured with the "Reduced Sense of Accomplishment" scale of the Athlete Burnout Questionnaire. Reaction times were measured with the finger pre-cueing task and with the action and reaction modes of the determination test. The complex structured data were analysed with multi-level modelling. Random intercept linear models showed that perceived performance was not related to reaction times on the finger pre-cueing task. Perceived performance significantly predicted reaction times on the action and reaction modes of the determination test. In rowers who were not selected for the team after completing two measurement sessions, this relationship did not exist in the action mode; deselection was a moderator. Thus, a significant relationship between reaction times on the determination test and perceived performance was observed. It was concluded that the determination test could be a useful tool to monitor rowers' responses to training, although several issues should be resolved before it can be used in practice

QTL detection and allelic effects for growth and fat traits in outbred pig populations

Quantitative trait loci (QTL) for growth and fatness traits have previously been identified on chromosomes 4 and 7 in several experimental pig populations. The segregation of these QTL in commercial pigs was studied in a sample of 2713 animals from five different populations. Variance component analysis (VCA) using a marker-based identity by descent (IBD) matrix was applied. The IBD coefficient was estimated with simple deterministic (SMD) and Markov chain Monte Carlo (MCMC) methods. Data for two growth traits, average daily gain on test and whole life daily gain, and back fat thickness were analysed. With both methods, seven out of 26 combinations of population, chromosome and trait, were significant. Additionally, QTL genotypic and allelic effects were estimated when the QTL effect was significant. The range of QTL genotypic effects in a population varied from 4.8% to 10.9% of the phenotypic mean for growth traits and 7.9% to 19.5% for back fat trait. Heritabilities of the QTL genotypic values ranged from 8.6% to 18.2% for growth traits, and 14.5% to 19.2% for back fat. Very similar results were obtained with both SMD and MCMC. However, the MCMC method required a large number of iterations, and hence computation time, especially when the QTL test position was close to the marker

Quiver presentations and isomorphisms of Hecke categories and Khovanov arc algebras

We prove that the extended Khovanov arc algebras are isomorphic to the basic algebras of anti-spherical Hecke categories for maximal parabolics of symmetric groups. We present these algebras by quiver and relations and provide the full submodule lattices of Verma modules

The anti-spherical Hecke categories for Hermitian symmetric pairs

We calculate the $p$-Kazhdan--Lusztig polynomials for Hermitian symmetric pairs and prove that the corresponding anti-spherical Hecke categories categories are standard Koszul. We prove that the combinatorial invariance conjecture can be lifted to the level of graded Morita equivalences between subquotients of these Hecke categories

Detection of multiple quantitative trait loci and their pleiotropic effects in outbred pig populations

<p>Abstract</p> <p>Background</p> <p>Simultaneous detection of multiple QTLs (quantitative trait loci) may allow more accurate estimation of genetic effects. We have analyzed outbred commercial pig populations with different single and multiple models to clarify their genetic properties and in addition, we have investigated pleiotropy among growth and obesity traits based on allelic correlation within a gamete.</p> <p>Methods</p> <p>Three closed populations, (A) 427 individuals from a Yorkshire and Large White synthetic breed, (B) 547 Large White individuals and (C) 531 Large White individuals, were analyzed using a variance component method with one-QTL and two-QTL models. Six markers on chromosome 4 and five to seven markers on chromosome 7 were used.</p> <p>Results</p> <p>Population A displayed a high test statistic for the fat trait when applying the two-QTL model with two positions on two chromosomes. The estimated heritabilities for polygenic effects and for the first and second QTL were 19%, 17% and 21%, respectively. The high correlation of the estimated allelic effect on the same gamete and QTL test statistics suggested that the two separate QTL which were detected on different chromosomes both have pleiotropic effects on the two fat traits. Analysis of population B using the one-QTL model for three fat traits found a similar peak position on chromosome 7. Allelic effects of three fat traits from the same gamete were highly correlated suggesting the presence of a pleiotropic QTL. In population C, three growth traits also displayed similar peak positions on chromosome 7 and allelic effects from the same gamete were correlated.</p> <p>Conclusion</p> <p>Detection of the second QTL in a model reduced the polygenic heritability and should improve accuracy of estimated heritabilities for both QTLs.</p

Relations among basic psychological needs, PE-motivation and fundamental movement skills in 9–12-year-old boys and girls in Physical Education

: Many children aged 9–12 appear to have low levels of fundamental movement skills (FMS). Physical education (PE) is important because PE-teachers can teach children a variety of FMS and can influence PE-motivation. However, declined levels of PE-motivation are reported in the final grades of elementary school. Therefore, more insight in the relations between PE-motivation and FMS is needed. Purposes: In the first phase, instruments to measure the satisfaction of basic psychological needs (competence, autonomy, classmate relatedness and teacher relatedness) and PE-motivation (autonomous and controlled) in 9–12-year-old children were developed and validated. The purpose of the second phase was to examine the influence of basic psychological needs on PE-motivation, the influence of PE-motivation on locomotor skills, object control skills and balance skills, and the direct influence of basic psychological needs on FMS for boys and girls aged 9–12. Participants and data collection: In the first phase, 172 children (82 boys, 90 girls, M = 10.72 years ± 0.77) filled out questionnaires assessing the satisfaction of their basic psychological needs and motivation for PE. Forty-eight children completed the questionnaires again 4 weeks later. In the second phase, a total of 138 children (66 boys, 72 girls, 10.8 years ± .79) (three schools from phase 1 and one new school) participated. Children from the new school also completed the questionnaires and all children conducted the subtest for speed and agility, upper limb coordination and balance of the Bruininks-Oseretsky Test of Motor Proficiency 2. Data analysis: In phase 1, linear weighted Kappa's and the Mokken Scale Program for polychotomous items were used to test reliability and validity. In phase 2, Pearson's correlations and multiple linear regression analyses were performed to examine the relations. Findings: Regarding phase 1, all subscales were reliable and the validity was considered moderate to strong except for the autonomy subscale, which was not reliable and valid. With respect to phase 2, all basic psychological needs, except autonomy among girls, had moderate to strong correlations with autonomous PE-motivation. Teacher relatedness was the most important predictor for boys and girls, while the second predictor was classmate relatedness for boys and competence for girls. No positive significant relations between basic psychological needs and FMS and between PE-motivation and FMS were found. In contrary, moderate but negative relations between teacher relatedness and balance skills and between autonomous PE-motivation and balance skills were found for boys. Conclusions: The results confirmed the importance of the basic psychological needs in the prediction of autonomous PE-motivation in 9–12-year-old children. Although all needs should be supported by the PE-teacher, it is important to be aware of the different impact of the needs on autonomous PE-motivation for boys and girls. Despite the missing relations with FMS, PE-teachers seem to be able to autonomously motivate children for PE regardless of their FMS proficiency

Tracking performance and its underlying characteristics in talented swimmers:a longitudinal study during the junior-to-senior transition

The present study strived to gain a more profound understanding of the distinctions in development between swimmers who are considered to be on track to the senior elite level compared to those who are not. Longitudinal data of 29 talented sprint and middle-distance swimmers (12 males; 17 females) on season best performances (season best times) and underlying performance characteristics (anthropometrics, starts, turns, maximal swimming velocity, stroke index [SI, an indirect measure of swimming efficiency] and lower body power) were collected over four swimming seasons (median of n = 3 seasons per swimmer). Based on their season best performance at early senior age (males aged 18–19; females aged 17–18), some swimmers were considered to be on track to reach the elite level (referred to as high-performing seniors; 6 males and 10 females), whereas others were not (referred to as lower-performing seniors; 6 males and 7 females). Retrospectively studying these swimmers (males and females separately), we found that all high-performing seniors were already on track to the elite level at late junior age (males aged 17; females aged 16), evidenced with faster season best performances throughout their transition compared to their lower-performing peers (p &lt; 0.05). Independent sample t-tests revealed that high-performing seniors significantly outscored their lower-performing peers on maximal swimming velocity (males and females), starts and turns (males), SI (females) and lower body power (females) at late junior age (p &lt; 0.05). Additionally, multilevel models showed faster rates of development for high-performing seniors on turns and maximal swimming velocity (males), and SI (females) compared to lower-performing peers during the junior-to-senior transition (p &lt; 0.05). Particularly, the higher initial levels of swim performance and underlying characteristics at late junior age as well as the ability to keep progressing on season best performances (males and females), turns and maximal swimming velocity (males), and SI (females) during the junior-to-senior transition, may be crucial factors in the attainment of swimming expertise.</p

Student-athletes’ need for competence, effort, and attributions of success and failure:Differences between sport and school

Our purpose was to show that highly skilled student-athletes (n1⁄4146, 41.1% female, mean age 14.1years) differ across domains with regard to their need for competence, effort, and attributions. As hypothesized, the results show that relative to the school domain, in the sport domain, student-athletes had a stronger need for competence, a higher willingness to exert effort, and a stronger tendency to ascribe positive outcomes to personal effort, regardless of sex and sport. For professional practice, our findings imply that effective psychological interventions such as attributional retraining should vary across domains, particularly in case of explaining positive outcomes