Theory to Practice: Performance Preparation Models in Contemporary High-Level Sport Guided by an Ecological Dynamics Framework

Abstract: A fundamental challenge for practitioners in high-level sporting environments concerns how to support athletes in adapting behaviours to solve emergent problems during competitive performance. Guided by an ecological dynamics framework, the design and integration of competitive performance preparation models that place athlete-environment interactions at the heart of the learning process may address this challenge. This ecological conceptualisation of performance preparation signifies a shift in a coach’s role; evolving from a consistent solution provider to a learning environment designer who fosters local athlete-environment interactions. However, despite the past decades of research within the ecological dynamics framework developing an evidence-based, theoretical conceptualisation of skill acquisition, expertise and talent development, an ongoing challenge resides within its practical integration into sporting environments. This article provides two case examples in which high-level sports organisations have utilised an ecological dynamics framework for performance preparation in Australian football and Association Football. A unique perspective is offered on experiences of professional sport organisations attempting to challenge traditional ideologies for athlete performance preparation by progressing the theoretical application of ecological dynamics. These case examples intend to promote the sharing of methodological ideas to improve athlete development, affording opportunities for practitioners and applied scientists to accept, reject or adapt the approaches presented here to suit their specific ecosystems

High tumour contamination of leukaphereses in patients with small cell carcinoma of the lung: a comparison of immunocytochemistry and RT-PCR

In small-cell lung carcinoma (SCLC) tumour cell contamination of leukaphereses is unknown. The present study was performed to define appropriate markers for reverse transcriptase polymerase chain reaction (RT-PCR), then to assess the contamination rate of leukaphereses and corresponding bone marrow samples. Immunocytochemistry (ICC) and RT-PCR methods were also compared. Among the 33 patients included, analyses were performed in 16 who had multiple leukaphereses and 17 who had only bone marrow. Leukapheresis products and bone marrow were analysed by ICC using several specific monoclonal antibodies against neural-cell adhesion molecule (N-CAM), epithelial glycoprotein (EGP-40) and cytokeratins (CK). Samples were also analyzed by RT-PCR for expression for N-CAM, synaptophysin, neuron-specific enolase, chromogranin, cytokeratin-18/-19, CEA, EGP-40, apomucin type 1 (MUC-1) and human endothelial cell-specific molecule (ESM-1). Using ICC staining, contaminating tumour cells were detected in 34% of leukaphereses (27% in patients with limited disease and 43% in those with extensive disease). N-CAM was the most reliable marker for detection of contamination. For RT-PCR, CK-19 and CEA were the only appropriate markers. Positive signal rate in leukaphereses increased to 78% (89% for patients with limited disease and 67% for extensive disease). In bone marrow, both techniques were in agreement whereas in leukaphereses, RT-PCR was better than ICC. A high rate of tumour cell contamination was demonstrated not only in bone marrow but also in leukaphereses from SCLC patients. The most appropriate technique was RT-PCR mainly in patients with limited disease. © 2001 Cancer Research Campaign http://www.bjcancer.co

Defining the actinic keratosis field: a literature review and discussion

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Quantitative Detection of Schistosoma japonicum Cercariae in Water by Real-Time PCR

In China alone, an estimated 30 million people are at risk of schistosomiasis, caused by the Schistosoma japonicum parasite. Disease has re-emerged in several regions that had previously attained transmission control, reinforcing the need for active surveillance. The environmental stage of the parasite is known to exhibit high spatial and temporal variability, and current detection techniques rely on a sentinel mouse method which has serious limitations in obtaining data in both time and space. Here we describe a real-time PCR assay to quantitatively detect S. japonicum cercariae in laboratory samples and in natural water that has been spiked with known numbers of S. japonicum. Multiple primers were designed and assessed, and the best performing set, along with a TaqMan probe, was used to quantify S. japonicum. The resulting assay was selective, with no amplification detected for Schistosoma mansoni, Schistosoma haematobium, avian schistosomes nor organisms present in non-endemic surface water samples. Repeated samples containing various concentrations of S. japonicum cercariae showed that the real-time PCR method had a strong linear correlation (R2 = 0.921) with light microscopy counts, and the detection limit was below the DNA equivalent of half of one cercaria. Various cercarial concentrations spiked in 1 liter of natural water followed by a filtration process produced positive detection from 93% of samples analyzed. The real-time PCR method performed well quantifying the relative concentrations of various spiked samples, although the absolute concentration estimates exhibited high variance across replicated samples. Overall, the method has the potential to be applied to environmental water samples to produce a rapid, reliable assay for cercarial location in endemic areas

Detection and characteristics of microvascular obstruction in reperfused acute myocardial infarction using an optimized protocol for contrast-enhanced cardiovascular magnetic resonance imaging

Several cardiovascular magnetic resonance imaging (CMR) techniques are used to detect microvascular obstruction (MVO) after acute myocardial infarction (AMI). To determine the prevalence of MVO and gain more insight into the dynamic changes in appearance of MVO, we studied 84 consecutive patients with a reperfused AMI on average 5 and 104 days after admission, using an optimised single breath-hold 3D inversion recovery gradient echo pulse sequence (IR-GRE) protocol. Early MVO (2 min post-contrast) was detected in 53 patients (63%) and late MVO (10 min post-contrast) in 45 patients (54%; p = 0.008). The extent of MVO decreased from early to late imaging (4.3 ± 3.2% vs. 1.8 ± 1.8%, p < 0.001) and showed a heterogeneous pattern. At baseline, patients without MVO (early and late) had a higher left ventricular ejection fraction (LVEF) than patients with persistent late MVO (56 ± 7% vs. 48 ± 7%, p < 0.001) and LVEF was intermediate in patients with early MVO but late MVO disappearance (54 ± 6%). During follow-up, LVEF improved in all three subgroups but remained intermediate in patients with late MVO disappearance. This optimised single breath-hold 3D IR-GRE technique for imaging MVO early and late after contrast administration is fast, accurate and allows detection of patients with intermediate remodelling at follow-up