Self-controlled video feedback on tactical skills for soccer teams results in more active involvement of players

Many studies have shown that self-controlled feedback is beneficial for learning motor tasks, andthat learners prefer to receive feedback after supposedly good trials. However, to date all studiesconducted on self-controlled learning have used individual tasks and mainly relatively simpleskills. Therefore, the aim of this study was to examine self-controlled feedback on tactical skills insmall-sided soccer games. Highly talented youth soccer players were assigned to a self-control oryoked group and received video feedback on their o ffensive performance in 3 vs. 2 small-sidedgames. The results showed that the self-control group requested feedback mostly after good trials,that is, after they scored a goal. In addition, the perceived performance of the self-control groupwas higher on feedback than on no-feedback trials. Analyses of the conversations around thevideo feedback revealed that the players and coach discussed good and poor elements of per-formance and how to improve it. Although the coach had a major role in these conversations, theplayers of the self-control group spoke more and showed more initiative compared to the yokedgroup. The results revealed no significant beneficial effect of self-controlled feedback on per-formance as judged by the coach. Overall, the findings suggest that in such a complex situation assmall-sided soccer games, self-controlled feedback is used both to confirm correct performanceelements and to determine and correct errors, and that self-controlled learning stimulates theinvolvement of the learner in the learning process

In situ examination of decision-making skills and gaze behaviour of basketball players

In this study we examined in situ decision-making skills and gaze behaviour of skilled female basketball players. Players participated as ball carriers in a specific 3 vs 3 pick-and-roll basketball play. Playing both on the right and left side of the court and facing three types of defensive play, they chose and performed one of four options: shoot, drive to the basket, pass to the screener or pass to the corner player. We concurrently measured gaze behaviour to examine the direct relationship between gaze and decision making. As one of the first studies examining decision making and gaze behaviour in situ, this study found support for the embodied choice framework as the results showed that handling the ball with the dominant or non-dominant hand influenced the decisions that were made. Gaze measures suggested that peripheral vision may serve a significant role in decision making in situ, whereas players mainly relied on central vision to execute an action. Furthermore, this study underlined the need for developing and using newer and more informative methods to analyse gaze

Presence of Epstein-Barr virus latency type III at the single cell level in post- transplantation lymphoproliferative disorders and AIDS related lymphomas

AIMS: To investigate the expression pattern of Epstein-Barr virus (EBV) latent genes at the single cell level in post-transplantation lymphoproliferative disorders and acquired immunodefiency syndrome (AIDS) related lymphomas, in relation to cellular morphology. METHODS: Nine post-transplantation lymphoproliferative disorders and three AIDS related lymphomas were subjected to immunohistochemistry using monoclonal antibodies specific for EBV nuclear antigen 1 (EBNA1) (2H4), EBNA2 (PE2 and the new rat anti-EBNA2 monoclonal antibodies 1E6, R3, and 3E9), and LMP1 (CS1-4 and S12). Double staining was performed combining R3 or 3E9 with S12. RESULTS: R3 and 3E9 anti-EBNA2 monoclonal antibodies were more sensitive than PE2, enabling the detection of more EBNA2 positive lymphoma cells. Both in post-transplantation lymphoproliferative disorders and AIDS related lymphomas, different expression patterns were detected at the single cell level. Smaller neoplastic cells were positive for EBNA2 but negative for LMP1. Larger and more blastic neoplastic cells, sometimes resembling Reed-Sternberg cells, were LMP1 positive but EBNA2 negative (EBV latency type II). Morphologically intermediate neoplastic cells coexpressing EBNA2 and LMP1 (EBV latency type III), were detected using R3 and 3E9, and formed a considerable part of the neoplastic population in four of nine post-transplantation lymphoproliferative disorders and two of three AIDS related lymphomas. All samples contained a subpopulation of small tumour cells positive exclusively for Epstein-Barr early RNA and EBNA1. The relation between cellular morphology and EBV expression patterns in this study was less pronounced in AIDS related lymphomas than in post-transplantation lymphoproliferative disorders, because the AIDS related lymphomas were less polymorphic than the post-transplantation lymphoproliferative disorders. CONCLUSIONS: In post-transplantation lymphoproliferative disorders and AIDS related lymphomas, EBV latency type III can be detected by immunohistochemistry in a subpopulation of tumour cells using sensitive monoclonal antibodies R3 and 3E9. Our data suggest that EBV infected tumour cells in these lymphomas undergo gradual changes in the expression of EBV latent genes, and that these changes are associated with changes in cellular morphology

Analysing gene expressions with GRANK.

Unravelling overlapping clusters of functionally linked genes is a major challenge to current clustering programs. Algorithm GRANK permits systematic study of overlap between clusters of genes of a similar expression profile and large variation across a series of microarrays. AVAILABILITY: GRANK is freely available from http://www.bio.vu.nl/microb/research/tumor.html provided one adheres to the end-user license agreement in the associated manual. SUPPLEMENTARY INFORMATION: Above website also supplies the in- and output files used in the example run