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The aim of this study was to quantify the impact of selections and shared selections in the rugby union. Players’ names, positions, and number of selections were collected for all XV de France’s games (1906–2014). Every team’s percentage of renewal of workforce was calculated for backs and forwards. During the 1987–2014 period, all second row forwards (locks), halfbacks, and centres’ shared selections (number of times when two players have competed together) were recreated. The Best vs. Rest method was applied to these remodelled dyads. They were analysed and compared with surrounding teammates as well as opponents. Head coaches similarly change their workforce for upcoming matches after winning or losing (around 30%), but losing teams renew significantly more positions in their line-ups. The recreated halfbacks, locks, and centres reveal a common pattern. Whether victorious or not, the ‘renewed couples’ victory percentage will congregate towards the XV de France’s victory percentage. For all the best recreated couples, the cumulated number of selections for forwards’ is always higher than the ones part of less efficient teams: 231.3?±?80 vs. 212.9?±?91 selections for locks’ teammates (Effect sizes (ES) small, possibly positive, 54.8%). In best recreated couples, number 8’s are significantly more experienced than their counterparts in less efficient pairs (ES small, likely positive, 76.3%). The XV de France’s collective effectiveness relies on a balance between stability and workforce renewal, which allows the building of specific position interactions and builds on experimented forwards packs. Selections and shared selections are serious collective performance parameters associated with performance.  相似文献   
23.
The aim of this study was to compare the training effects based on repeated sprint ability (RSA) (with one change of direction) with an intensive repeated sprint ability (IRSA) (with two changes of direction) on jump performance and aerobic fitness. Eighteen male basketball players were assigned to repeated sprint ability and intensive repeated sprint ability training groups (RSAG and IRSAG). RSA, IRSA, squat jump (SJ), countermovement jump (CMJ) and Yo-Yo intermittent recovery level 1 test were assessed before and after four training weeks. The RSA and IRSA trainings consisted of three sets of six sprints (first two weeks) and eight sprints (second two weeks) with 4-min sets recovery and 20-s of sprints recovery. Four weeks of training led to an overall improvement in most of the measures of RSA, but little evidence of any differences between the two training modes. Jump performance was enhanced: CMJ of 7.5% (< 0.0001) and 3.1% (= 0.016) in IRSAG and RSAG respectively. While SJ improved of 5.3% (= 0.003) for IRSAG and 3.4% (= 0.095) for RSAG. Conversely the Yo-Yo distance increased 21% (= 0.301) and 34% (= 0.017) in IRSAG and RSAG respectively. Therefore, short-term repeated sprint training with one/two changes of direction promotes improvements in both RSA and IRSA respectively but the better increase on jump performance shown a few changes on sprint and endurance performances.  相似文献   
24.
A method aimed at the development of an America’s Cup racing yacht bulb is developed and validated against experimental data. The method relies heavily on Reynolds Averaged Navier Stokes computational fluid dynamics (CFD) and also factors in gravitational and aerodynamics effects through the use of a Velocity Prediction Program. Initial extensive use of towing tank results is made to be able to validate the CFD solution and thus develop a solid ground for predictive work. Then, in order to narrow down the focus on bulb developments, decoupled hypotheses are made on the influence of the hull and free surface wave. The development of a detailed performance analysis chart of a known base bulb allows the use of a relatively small series of CFD simulations together with physical hypotheses to assess any given bulb performance relative to the known base. The discussion of the results on a specific development highlights the promises and limitations of the method; final full scale results are discussed and analysed as well.  相似文献   
25.
We present a microfluidic device capable of separating platelets from other blood cells in continuous flow using dielectrophoresis field-flow-fractionation. The use of hydrodynamic focusing in combination with the application of a dielectrophoretic force allows the separation of platelets from red blood cells due to their size difference. The theoretical cell trajectory has been calculated by numerical simulations of the electrical field and flow speed, and is in agreement with the experimental results. The proposed device uses the so-called "liquid electrodes" design and can be used with low applied voltages, as low as 10 V(pp). The obtained separation is very efficient, the device being able to achieve a very high purity of platelets of 98.8% with less than 2% cell loss. Its low-voltage operation makes it particularly suitable for point-of-care applications. It could further be used for the separation of other cell types based on their size difference, as well as in combination with other sorting techniques to separate multiple cell populations from each other.  相似文献   
26.
IntroductionThe Fourth Universal Definition of Myocardial Infarction Global Taskforce recommends the use of high sensitive troponin (hs-Tn) assays in the diagnosis of acute myocardial infarction. We evaluated the analytical performance of the Atellica IM High-sensitivity Troponin I Assay (hs-TnI) (Siemens Healthcare Diagnostics Inc., Tarrytown, USA) and compared its performance to other hs-TnI assays (Siemens Advia Centaur, Dimension Vista, Dimension EXL, and Abbott Architect (Wiesbaden, Germany)) at one or more sites across Europe.Materials and methodsPrecision, detection limit, linearity, method comparison, and interference studies were performed according to Clinical and Laboratory Standards Institute protocols. Values in 40 healthy individuals were compared to the manufacturer’s cut-offs. Sample turnaround time (TAT) was examined.ResultsImprecision repeatability CVs were 1.1–4.7% and within-lab imprecision were 1.8–7.6% (10.0–25,000 ng/L). The limit of blank (LoB), detection (LoD), and quantitation (LoQ) aligned with the manufacturer’s values of 0.5 ng/L, 1.6 ng/L, and 2.5 ng/L, respectively. Passing-Bablok regression demonstrated good correlations between Atellica IM analyser with other systems; some minor deviations were observed. All results in healthy volunteers fell below the 99th percentile URL, and greater than 50% of each sex demonstrated values above the LoD. No interference was observed for biotin (≤ 1500 µg/L), but a slight bias at 5.0 g/L haemoglobin and 50 ng/L Tn was observed. TAT from was fast (mean time = 10.9 minutes) and reproducible (6%CV).ConclusionsReal-world analytical and TAT performance of the hs-TnI assay on the Atellica IM analyser make this assay fit for routine use in clinical laboratories.  相似文献   
27.
Affordable and ubiquitous online communications (social media) provide the means for flows of ideas and opinions and play an increasing role for the transformation and cohesion of society – yet little is understood about how online opinions emerge, diffuse, and gain momentum. To address this problem, an opinion formation framework based on content analysis of social media and sociophysical system modeling is proposed. Based on prior research and own projects, three building blocks of online opinion tracking and simulation are described: (1) automated topic, emotion and opinion detection in real-time, (2) information flow modeling and agent-based simulation, and (3) modeling of opinion networks, including special social and psychological circumstances, such as the influence of emotions, media and leaders, changing social networks etc. Finally, three application scenarios are presented to illustrate the framework and motivate further research.  相似文献   
28.
According to the Grain Size Accommodation hypothesis (Lallier & Carreiras, 2017), learning to read in two languages differing in orthographic consistency leads to a cross-linguistic modulation of reading and spelling processes. Here, we test the prediction that bilingualism may influence the manifestations of dyslexia. We compared the deficits of English monolingual and early Welsh–English bilingual dyslexic adults on reading and spelling irregular English words and English-like pseudowords. As predicted, monolinguals were relatively more impaired in reading pseudowords than irregular words, whereas the opposite was true for bilinguals. Moreover, monolinguals showed stronger sublexical processing deficits than bilinguals and were poorer spellers overall. This study shows that early bilingual reading experience has long-lasting effects on the manifestations of dyslexia in adulthood. It demonstrates that learning to read in a consistent language like Welsh in addition to English gives bilingual dyslexic adults an advantage in English literacy tasks strongly relying on phonological processing.  相似文献   
29.
Abstract

The aim of the study is the modelling of training responses with a variable dose-response model in a sport discipline that requires highly complex coordination. We propose a method to optimise the training programme plan using the potential maximal performance gain associated with overload and tapering periods. Data from five female elite gymnasts were collected over a 3-month training period. The relationship between training amounts and performance was then assessed with a non-linear model. The optimal magnitude of training load reduction and its duration were investigated with and without an overload period using simulation procedures based on individual responses to training. The correlation between actual and modelled performances was significant (R 2 = 0.81 ± 0.02, P < 0.01). The standard error was 2.7%. Simulations revealed that taper preceded by an overload period allows a higher performance to be achieved compared to an absence of overload period (106.3 ± 0.3% vs. 105.1 ± 0.3%). With respect to the pre-taper load, the model predicts that optimal load reductions during taper were 48.4 ± 0.7% and 42.5 ± 1.0% for overloading and non-overloading strategies, respectively. Moreover, optimal durations of the taper period were 34 ± 0.5 days and 22 ± 0.5 days for overloading and non-overloading strategies, respectively. In conclusion, the study showed that the variable dose-response model describes precisely the training response in gymnasts.  相似文献   
30.
Abstract

Using self-determination theory (SDT) (Deci, E.L., & Ryan, R.M. (1985). Intrinsic motivation and self-determination in human behavior. New York, NY: Plenum) as the theoretical framework, we conducted a longitudinal investigation of the temporal ordering between motivation and burnout among youth athletes in intensive training setting. Data were collected from 145 table tennis players in intensive training centres at three time points during a 2-month period characterised by a simultaneous increase in social, physical and psychological demands for these athletes. Structural equation modelling of cross-lagged panel models was used to test the hypotheses. Results showed significant paths leading from athlete burnout – especially sport devaluation and reduced sense of accomplishment – at time 1 to amotivation, intrinsic and extrinsic motivations at times 2 and 3. Only two significant paths leading from motivation (introjected regulation at time 1) to burnout (emotional/physical exhaustion at time 2 and reduced sense of accomplishment at time 3) were identified. Overall, our results suggest that athlete burnout predicts motivation over time but motivation did not predict athlete burnout over time. Results are discussed in terms of current research findings on SDT.  相似文献   
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