Effects of Cognitive Stress on the Temporal Anticipation of a Timing Motor Task

The study was designed to investigate the effects of cognitive stress on the temporal anticipation of a timing motor task. The experimental design applied was a repeated measures design with two independent variables (cognitive stress and levels of difficulty - easy, intermediate and difficult). The participants of this study consist of 18 male and 19 female undergraduates of the Physical Education programme of University Putra Malaysia. The participants were required to perform a timing motor across three levels of difficulty and under two conditions i.e. without cognitive stress and under cognitive stress. Cognitive stress was induced via the continuous subtraction of two from a two-digit number. Participants performed the task individually and the sequence of the experimental task was counterbalanced. A two-way within subject's ANOVA was performed to ascertain the effects of cognitive stress on the temporal anticipation of the timing motor task. The data analysis revealed a significant difference in means for the stress main effect (A = 64, E (1.35) = 19.89, P = .00); and the task main effect (A = .84, E (2,34) = 3.35, p < .05). Post hoc comparisons produced a significant difference in the means of the performance of the timing motor task at all three levels of difficulty. This showed that cognitive stress had an effect on the temporal anticipation of the timing motor task. A two way mixed design ANOVA was conducted was performed to ascertain the effects of cognitive stress on the temporal anticipation of the timing motor task with regard to gender. The task main effect was significant (A = .59, E (5, 170) = 6.70, P = .01). Follow up comparisons revealed significant difference in the performance of the experimental task at the easy level without cognitive stress, intermediate level without cognitive stress and the easy level under cognitive stress. This showed that there was a significant difference in the performance of the timing motor at the three levels mentioned

The differences between gross motor performance amongst children according to ethnic and age chronology

Gross motor skills are important elements that are often associated with the activeness of children in sports and physical activity. The better motor performance level amongst children is reflected by the higher level of involvement in sports and physical activity. Therefore, the purpose of this study is to investigate the level of gross motor performance amongst children based on ethnic and chronological age. The subjects of the study consist of two different ethnic groups namely, Malays (n=38) and Indians (n=34), respectively. A total of 72 subjects aged between 8 and 9 years old (8.51 ± 50 years) volunteered for this study. The Test of Gross Motor Development (TGMD-2) is the instrument used in order to assess the gross motor performance amongst the children. Two gross motor components assessed were locomotor and object manipulation. The t-test analysis found that there was no significant difference on the level of motor performance between the ethnicities either in locomotor [t (70) = .31, p (.75)> .05] or object manipulation [t (70) = 1.65, p (.10)> .05]. Meanwhile, the results attained from the Gross Motor Quotient (GMQ) score demonstrated that all the participants regardless of their ethnicity, exhibited a lower level of gross motor performance compared to age equivalent standard score. In conclusion, ethnic differences do not affect the level of gross motor performance either in locomotor or object manipulation

Chaste: an open source C++ library for computational physiology and biology

Chaste - Cancer, Heart And Soft Tissue Environment - is an open source C++ library for the computational simulation of mathematical models developed for physiology and biology. Code development has been driven by two initial applications: cardiac electrophysiology and cancer development. A large number of cardiac electrophysiology studies have been enabled and performed, including high performance computational investigations of defibrillation on realistic human cardiac geometries. New models for the initiation and growth of tumours have been developed. In particular, cell-based simulations have provided novel insight into the role of stem cells in the colorectal crypt. Chaste is constantly evolving and is now being applied to a far wider range of problems. The code provides modules for handling common scientific computing components, such as meshes and solvers for ordinary and partial differential equations (ODEs/PDEs). Re-use of these components avoids the need for researchers to "re-invent the wheel" with each new project, accelerating the rate of progress in new applications. Chaste is developed using industrially-derived techniques, in particular test-driven development, to ensure code quality, re-use and reliability. In this article we provide examples that illustrate the types of problems Chaste can be used to solve, which can be run on a desktop computer. We highlight some scientific studies that have used or are using Chaste, and the insights they have provided. The source code, both for specific releases and the development version, is available to download under an open source Berkeley Software Distribution (BSD) licence at http://www.cs.ox.ac.uk/chaste, together with details of a mailing list and links to documentation and tutorials

Kesan penskalaan tinggi jaring terhadap prestasi panjang rali permainan badminton dalam kalangan kanak-kanak

Kajian ini bertujuan mengkaji kesan penskalaan tinggi jaring terhadap prestasi panjang rali permainan badminton dalam kalangan kanak-kanak. Kajian menggunakan reka bentuk eksperimen untuk pengukuran berulang. Seramai 48 (N=48) kanak-kanak berumur tujuh hingga sembilan tahun dipilih secara rawak sebagai peserta kajian. Peserta telah dibahagikan kepada 24 pasangan yang setara dari segi tahap kemahiran dan jantina (lelaki, n=12 pasangan, perempuan, n=12 pasangan). Semua peserta bermain secara berpasangan menggunakan empat situasi tinggi jaring yang berbeza iaitu situasi A (155 cm), situasi B (127.66 cm), situasi C (117.44 cm) dan situasi D (104.68 cm). Susunan perlawanan antara keempat-empat situasi dijalankan secara timbalbalik. Semua perlawanan dijalankan menggunakan sistem pertandingan perseorangan dengan kiraan 11 mata dengan dua set setiap situasi. Data prestasi panjang rali telah dikumpul menggunakan rakaman video. Data telah dianalisis menggunakan ujian ANOVA sehala untuk pengukuran berulang. Keputusan Mauchly’s Test of Sphericity menunjukkan bahawa terdapat perbezaan skor min prestasi panjang rali yang signifikan antara keempat-empat situasi tinggi jaring [F(2.30, 52.88)=30.37, p<.05]. Dapatan kajian menunjukkan bahawa penskalaan tinggi jaring mampu meningkatkan prestasi panjang rali dalam kalangan kanak-kanak berumur tujuh hingga sembilan tahun

Psychological skills assessment and referee rugby sevens performance

This study aims to examine the psychological skills that are commonly used among referees rugby sevens and their relationship with referees’ performance. The Psychological Skills Inventory for Sports (Mahoney, Gabriel, & Perkins, 1987) was adapted and modified specifically for use by rugby sevens referees. It was administered to 132 rugby sevens referee (mean age 33.4 + 1.5 years; 132 males) of the Malaysian Rugby Union (MRU) which has been refereed in 10 rugby sevens tournament in Malaysia. The psychological skills variables employed in the questionnaire included confidence, anxiety management, mental preparation, motivation and concentration. The IRB Referee Sevens Performance Evaluation Form (r=0.94) was used to evaluate referee performance. These instruments measure the performance variable that contains the dimensions of control, communication, application of the law and the positioning. The descriptive statistics of the variables are Psychological skills (M= 120.14, SD= 6.97) and performance (M= 136.45, SD= 4.47) identified at a moderate level. Findings indicated no significant differences [F= (3, 72) =.636, p>0.05] in psychological skills across age levels but there are significant differences [F= (3, 128) =57.616, p<0.05] across experience levels. Highly experienced referees scored significantly higher in all psychological constructs compared to less experienced referees. Variables that showed strong and positive relationships with performance were anxiety management (r= .61), concentration (r= .57), confidence(r= .54) and motivation (r= .50). In conclusion, the psychological skills assessment can improve the efficacy of rugby referees and recommends that referee coaches increase the use of psychological skills in competitions and future training. Researchers should investigate the effectiveness of applied sport psychology interventions in enhancing referee performance in the future

Psychological skills assessment and referee rugby sevens performance

This study aims to examine the psychological skills that are commonly used among referees rugby sevens and their relationship with referees’ performance. The Psychological Skills Inventory for Sports (Mahoney, Gabriel, & Perkins, 1987) was adapted and modified specifically for use by rugby sevens referees. It was administered to 132 rugby sevens referee (mean age 33.4 + 1.5 years; 132 males) of the Malaysian Rugby Union (MRU) which has been refereed in 10 rugby sevens tournament in Malaysia. The psychological skills variables employed in the questionnaire included confidence, anxiety management, mental preparation, motivation and concentration. The IRB Referee Sevens Performance Evaluation Form (r=0.94) was used to evaluate referee performance. These instruments measure the performance variable that contains the dimensions of control, communication, application of the law and the positioning. The descriptive statistics of the variables are Psychological skills (M= 120.14, SD= 6.97) and performance (M= 136.45, SD= 4.47) identified at a moderate level. Findings indicated no significant differences [F= (3, 72) =.636, p>0.05] in psychological skills across age levels but there are significant differences [F= (3, 128) =57.616, p<0.05] across experience levels. Highly experienced referees scored significantly higher in all psychological constructs compared to less experienced referees. Variables that showed strong and positive relationships with performance were anxiety management (r= .61), concentration (r= .57), confidence(r= .54) and motivation (r= .50). In conclusion, the psychological skills assessment can improve the efficacy of rugby referees and recommends that referee coaches increase the use of psychological skills in competitions and future training. Researchers should investigate the effectiveness of applied sport psychology interventions in enhancing referee performance in the future

Role of psychological factors on the performance of elite soccer players

The application of psychological strategies to improve performance in sports has developed significantly over the past few decades. Nowadays, coaches are beginning to realize the significance of psychological factors in enhancing player’s performance. However, determining the magnitude of the impact of psychological factors in a soccer game may assist in developing player’s capacity to perform. This study aims to determine the role of psychological factors on the performance of elite soccer players. We enrolled elite players competing in the Malaysian Super League with a mean age of ± 25 years. Psychological constructs questionnaire proposed by PSIS-R-5 was administered to the players, and the scores of each player were recorded. We analyzed the performances of the players for eight weeks. A standard multiple regression was performed at p = 0.05 alpha levels with the motivation, confidence, anxiety control, mental preparation, team emphasis, concentration and cognition as (IVs) to predict performance (DV). A Noteworthy regression equation was found (F (7, 12) = 15.109, P < .001) with R² of .90 indicating that the model has approximately accounted for the total of 90% variability. Although correlations were found.57, .14, .88, .71, .65, .76 and .42 respectively between the (IVs) and the (DV), none of the (IVs) is a predictor of the (DV) (P > 0.05). Based on the results of this analysis, it is tempting to conclude that, despite the correlation between psychological factors and performance, psychological factors alone could not determine the performance of elite soccer players

Effect of Heart Structure on Ventricular Fibrillation in the Rabbit: A Simulation Study

Ventricular fibrillation (VF) is a lethal condition that affects millions worldwide. The mechanism underlying VF is unstable reentrant electrical waves rotating around lines called filaments. These complex spatio-temporal patterns can be studied using both experimental and numerical methods. Computer simulations provide unique insights including high resolution dynamics throughout the heart and systematic control of quantities such as fiber orientation and cellular kinetics that are not feasible experimentally. Here we study filament dynamics using two bi-ventricular 3-D high-resolution rabbit heart geometries, one with detailed fine structure and another without fine structure. We studied filament dynamics using anisotropic and isotropic conductivities, and with four cellular action potential models with different recovery kinetics. Spiral wave dynamics observed in isotropic two-dimensional sheets were not predictive of the behavior in the whole heart. In 2-D the four cell models exhibited stable reentry, meandering spiral waves, and spiral-wave breakup. In the whole heart with fine structure, all simulation results exhibited complex dynamics reminiscent of fibrillation observed experimentally. In the whole heart without fine structure, anisotropy acted to destabilize filament dynamics although the number of filaments was reduced compared to the heart with structure. In addition, in isotropic hearts without structure the two cell models that exhibited meandering spiral waves in 2-D, stabilized into figure-of-eight surface patterns. We also studied the sensitivity of filament dynamics to computer system configuration and initial conditions. After large simulation times, different macroscopic results sometimes occurred across different system configurations, likely due to a lack of bitwise reproducibility. The study conclusions were insensitive to initial condition perturbations, however, the exact number of filaments over time and their trends were altered by these changes. In summary, we present the following new results. First, we provide a new cell model that resembles the surface patterns of VF in the rabbit heart both qualitatively and quantitatively. Second, filament dynamics in the whole heart cannot be predicted from spiral wave dynamics in 2-D and we identified anisotropy as one destabilizing factor. Third, the exact dynamics of filaments are sensitive to a variety of factors, so we suggest caution in their interpretation and their quantitative analyses

Competitive anxiety levels of track and field athletes in rural area of Sabah

The purpose of the study was to examine the competitive anxiety level of track and field athletes in remote areas of Sabah. A total of 213 male athletic athletes aged between sixteen to eighteen years have participated in this study. The participants' competitive anxiety levels before competition were assessed and classified into three categories: cognitive anxiety, somatic anxiety, and self-confidence. The Competitive State Anxiety Inventory (CSAI-2) was utilized in this study, and participants completed the questionnaire 60 minutes before the competition began. The data were analyzed by using a one-way analysis of variance (ANOVA). The results showed that field athletes were significantly better compared to track athletes in cognitive anxiety and self-confidence, (p 0.05). The study found that field events athletes can cope with anxiety better than track events athletes. Hence, it was essential for track and field athletes to get a proper training program regarding their psychological demands before the competition. Low anxiety and high confidence levels can contribute to improved performance in athletes

Competitive anxiety levels of track and field athletes in rural area of Sabah

The purpose of the study was to examine the competitive anxiety level of track and field athletes in remote areas of Sabah. A total of 213 male athletic athletes aged between sixteen to eighteen years have participated in this study. The participants' competitive anxiety levels before competition were assessed and classified into three categories: cognitive anxiety, somatic anxiety, and self-confidence. The Competitive State Anxiety Inventory (CSAI-2) was utilized in this study, and participants completed the questionnaire 60 minutes before the competition began. The data were analyzed by using a one-way analysis of variance (ANOVA). The results showed that field athletes were significantly better compared to track athletes in cognitive anxiety and self confidence, (p 0.05). The study found that field events athletes can cope with anxiety better than track events athletes. Hence, it was essential for track and field athletes to get a proper training program regarding their psychological demands before the competition. Low anxiety and high confidence levels can contribute to improved performance in athletes