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711.
Christian T. L. Janssen Robert W. Schutz 《Research quarterly for exercise and sport》2013,84(4):339-344
Abstract A frequently occurring situation in college and professional football is that of a team catching up through two touchdowns after trailing by 14 points, with the game outcome being determined by the extra-point plays. For leagues allowing two-point converts, an optimal point-after strategy exists under quite reasonable assumptions, and depends upon the relative utility to the team of a win, tie, or loss and the probability of success with a (one-point) kick as opposed to a (two-point) run/pass. We illustrate with reference to the January 1984 Orange Bowl game, where the favored team followed a possibly suboptimal strategy, losing the game and the national championship. 相似文献
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In economics the Research Papers in Economics (RePEc) network has become an essential source for the gathering and the spread of both existing and new economic research. Furthermore, it is currently the largest bibliometric database in economic sciences containing 33 different indicators for more than 30,000 economists. Based on this bibliographic information RePEc calculates well-known rankings for authors and academic institutions. We provide some cautionary remarks concerning the interpretation of some provided bibliometric measures in RePEc. Moreover, we show how individual and aggregated rankings can be biased due to the employed ranking methodology. In order to select key indicators describing and assessing research performance of scientist, we propose to apply principal component analysis in this data-rich environment. This approach allows us to assign weights to each indicator prior to aggregation. We illustrate the approach by providing a new overall ranking of economists based on RePEc data. 相似文献
714.
Zuzana Svobodova Mohamad Reza Mohamadi Barbora Jankovicova Hermann Esselmann Romain Verpillot Markus Otto Myriam Taverna Jens Wiltfang Jean-Louis Viovy Zuzana Bilkova 《Biomicrofluidics》2012,6(2):024126-024126-12
Determination of amyloid β (Aβ) isoforms and in particular the proportion of the Aβ 1-42 isoform in cerebrospinal fluid (CSF) of patients suspected of Alzheimer’s disease might help in early diagnosis and treatment of that illness. Due to the low concentration of Aβ peptides in biological fluids, a preconcentration step prior to the detection step is often necessary. This study utilized on-chip immunoprecipitation, known as micro-immunoprecipitation (μIP). The technique uses an immunosorbent (IS) consisting of magnetic beads coated with specific anti-Aβ antibodies organized into an affinity microcolumn by a magnetic field. Our goal was to thoroughly describe the critical steps in developing the IS, such as selecting the proper beads and anti-Aβ antibodies, as well as optimizing the immobilization technique and μIP protocol. The latter includes selecting optimal elution conditions. Furthermore, we demonstrate the efficiency of anti-Aβ IS for μIP and specific capture of 5 Aβ peptides under optimized conditions using various subsequent analytical methods, including matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS), capillary electrophoresis, microchip electrophoresis, and immunoblotting. Synthetic Aβ peptides samples prepared in buffer and spiked in human CSF were analyzed. Finally, on-chip immunoprecipitation of Aβ peptides in human CSF sample was performed. 相似文献
715.
Alves CR Pasqua L Artioli GG Roschel H Solis M Tobias G Klansener C Bertuzzi R Franchini E Lancha Junior AH Gualano B 《Journal of sports sciences》2012,30(3):305-311
The purpose of this study was to determine the physiological, anthropometric, performance, and nutritional characteristics of the Brazil Canoe Polo National Team. Ten male canoe polo athletes (age 26.7 ± 4.1 years) performed a battery of tests including assessments of anthropometric parameters, upper-body anaerobic power (Wingate), muscular strength, aerobic power, and nutritional profile. In addition, we characterized heart rate and plasma lactate responses and the temporal pattern of the effort/recovery during a simulated canoe polo match. The main results are as follows: body fat, 12.3 ± 4.0%; upper-body peak and mean power, 6.8 ± 0.5 and 4.7 ± 0.4 W · kg(-1), respectively; 1-RM bench press, 99.1 ± 11.7 kg; peak oxygen uptake, 44.3 ± 5.8 mL · kg(-1) · min(-1); total energy intake, 42.8 ± 8.6 kcal · kg(-1); protein, carbohydrate, and fat intakes, 1.9 ± 0.1, 5.0 ± 1.5, and 1.7 ± 0.4 g · kg(-1), respectively; mean heart rate, 146 ± 11 beats · min(-1); plasma lactate, 5.7 ± 3.8 mmol · L(-1) at half-time and 4.6 ± 2.2 mmol · L(-1) at the end of the match; effort time (relative to total match time), 93.1 ± 3.0%; number of sprints, 9.6 ± 4.4. The results of this study will assist coaches, trainers, and nutritionists in developing more adequate training programmes and dietary interventions for canoe polo athletes. 相似文献
716.
Maria Rupprecht Josef Strasser Hans Gruber Christian Harteis 《Vocations and Learning》2010,3(1):39-54
Team leaders are expected to adequately analyse team conflicts. Both content and analytical depth of cognitive processes determine
team leaders’ performance and are assumed to differ with level of expertise. A study is reported in which team leaders at
four different levels of expertise (novices, semi-experts, experts, mediators) were compared in their analysis of a team conflict
presented in a computer-based simulation. Few differences were found between novices and semi-experts, whereas team leaders
and mediators differed both in content and in analytical depth of cognitive processes. It is not the amount of practice time
itself, which substantially impacts the content and depth of team leaders’ analyses of conflicts. Rather the quality of experience
is crucial for developing the ability to conduct an elaborated analysis of team conflicts. 相似文献
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