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101.
Jorge Ibáñez-Gijón Martinus Buekers Antoine Morice Guillaume Rao Nicolas Mascret Jérome Laurin 《Journal of sports sciences》2017,35(3):290-301
After more than 20 years since the introduction of ecological and dynamical approaches in sports research, their promising opportunity for interdisciplinary research has not been fulfilled yet. The complexity of the research process and the theoretical and empirical difficulties associated with an integrated ecological-dynamical approach have been the major factors hindering the generalisation of interdisciplinary projects in sports sciences. To facilitate this generalisation, we integrate the major concepts from the ecological and dynamical approaches to study behaviour as a multi-scale process. Our integration gravitates around the distinction between functional (ecological) and execution (organic) scales, and their reciprocal intra- and inter-scale constraints. We propose an (epistemological) scale-based definition of constraints that accounts for the concept of synergies as emergent coordinative structures. To illustrate how we can operationalise the notion of multi-scale synergies we use an interdisciplinary model of locomotor pointing. To conclude, we show the value of this approach for interdisciplinary research in sport sciences, as we discuss two examples of task-specific dimensionality reduction techniques in the context of an ongoing project that aims to unveil the determinants of expertise in basketball free throw shooting. These techniques provide relevant empirical evidence to help bootstrap the challenging modelling efforts required in sport sciences. 相似文献
102.
103.
Rodolfo herrero Ricaño Héctor Barrón Soto 《The American journal of distance education》2013,27(1):68-71
Abstract Since 1947, distance education in Mexico has had an important role for nonconventional populations. Considering that distance education is a heterogeneous and dynamic field, it is important to reflect on the need to improve quality as measured by our own standards. With that perspective in mind, a national meeting was organized to start a self‐diagnosis in which quality and access were the main concerns. Five hundred and twenty specialists from fifty‐one institutions participated in a national interactive synchronous meeting held in four regions. As a result of the meeting, thirty‐five criteria and 230 parameters of quality were established. The main conclusion of the meeting refers to the need for the elaboration of our own indicators for open and distance education. 相似文献
104.
Schmolke H Demming S Edlich A Magdanz V Büttgenbach S Franco-Lara E Krull R Klages CP 《Biomicrofluidics》2010,4(4):44113
Polyelectrolyte multilayers (PEMs) based on the combinations poly(diallyldimethylammonium chloride)∕poly(acrylic acid) (PDADMAC∕PAA) and poly(allylamine hydrochloride)∕PAA (PAH∕PAA) were adsorbed on poly(dimethylsiloxane) (PDMS) and tested for nonspecific surface attachment of hydrophobic yeast cells using a parallel plate flow chamber. A custom-made graft copolymer containing poly(ethylene glycol) (PEG) side chains (PAA-g-PEG) was additionally adsorbed on the PEMs as a terminal layer. A suitable PEM modification effectively decreased the adhesion strength of Saccharomyces cerevisiae DSM 2155 to the channel walls. However, a further decrease in initial cell attachment and adhesion strength was observed after adsorption of PAA-g-PEG copolymer onto PEMs from aqueous solution. The results demonstrate that a facile layer-by-layer surface functionalization from aqueous solutions can be successfully applied to reduce cell adhesion strength of S. cerevisiae by at least two orders of magnitude compared to bare PDMS. Therefore, this method is potentially suitable to promote planktonic growth inside capped PDMS-based microfluidic devices if the PEM deposition is completed by a dynamic flow-through process. 相似文献
105.
Kinematic differences of elite and high-performance tennis players in the cross court and down the line forehand 总被引:1,自引:0,他引:1
Landlinger J Lindinger SJ Stöggl T Wagner H Müller E 《Sports biomechanics / International Society of Biomechanics in Sports》2010,9(4):280-295
This study identified and compared the full body kinematics of different skill levels in the forehand groundstroke when balls were hit cross court and down the line. Forty-three three-dimensional retroreflective marker trajectories of six elite and seven high-performance players were recorded using an eight-camera 400 Hz, Vicon motion analysis system. The six highest horizontal velocity forehands with reliable kinematics of all participants were analysed for each specific situation (a total of 156 analysed shots). Significant differences (p < 0.01) and large effect sizes were observed between elite and high-performance players in linear velocity of the shoulder (2.0 vs. 1.2 m/s), angular velocity of the pelvis (295 vs. 168 degrees/s), and angular velocity of the upper trunk (453 vs. 292 degrees/s) at impact. The elite group showed a tendency towards higher racquet velocities at impact (p < 0.05). No significant differences were found in angular displacement of the racquet, hip alignment, or shoulder alignment at the completion of the backswing; nor did angular displacement vary significantly at impact. Irrespective of the group, different shoulder, hip, and racquet angles were found at impact, depending on the situation. The results should assist coaches when striving to improve their players' forehand. 相似文献
106.
107.
Özlem Sila Olgun PhD 《The Teacher Educator》2013,48(2):113-125
The main purpose of this study was to investigate the effects of active learning on preservice teachers' dignity, energy, self-management, community, and awareness (DESCA) abilities, attitudes toward teaching, and attitudes toward science. Third year preservice teachers (n = 77) from two different classes were involved in the study. One intact class was assigned as the experimental group, whereas the other intact class was assigned as the comparison group. The comparison group students received the instruction by traditional teaching, and the experimental group received instruction through an active learning paradigm. DESCA abilities and attitudes were measured before and after instruction. Results revealed that there was a significant difference favoring the active learning instruction on preservice teachers' DESCA scores; however, there was no significant difference on preservice teachers' attitudes toward teaching and science. 相似文献
108.
109.
Björn Öckert 《Economics of Education Review》2010,29(4):504-516
This paper exploits discontinuities and randomness in the college admissions in Sweden in 1982, to estimate the economic return to college in the 1990s. At the time, college admissions were highly selective and applicants were ranked with respect to their formal merits. Admissions were given to those ranked higher than some threshold value. At the margin, applicants were sometimes randomly assigned to college. Exploiting this Regression-Discontinuity design, individuals who were admitted in 1982 are estimated to have about 0.20 years longer college education in 1996. However, the earnings effects for applicants at the margin of admission are insignificant. Controlling for the college admission determinants, the OLS-estimates of the return to college is 1.4 percent in 1991–96. The IV-estimates are not significantly different from the OLS counterparts. 相似文献
110.
Jürgen Altmann 《Ethics and Information Technology》2013,15(2):137-152
Arming uninhabited vehicles (UVs) is an increasing trend. Widespread deployment can bring dangers for arms-control agreements and international humanitarian law (IHL). Armed UVs can destabilise the situation between potential opponents. Smaller systems can be used for terrorism. Using a systematic definition existing international regulation of armed UVs in the fields of arms control, export control and transparency measures is reviewed; these partly include armed UVs, but leave large gaps. For preventive arms control a general prohibition of armed UVs would be best. If that is unattainable, several measures should be taken. An explicit prohibition of autonomous attack, that is without a human decision, should be added to IHL. Concerning armed UVs remotely controlled by a human soldier, recommendations differ according to type or mission. New kinds of uninhabited nuclear-weapon carriers should be banned. Space weapons should be prohibited in general. UVs smaller than 0.2–0.5 m should be banned. Bigger remotely controlled armed UVs not equipped with weapons of mass destruction should be subject to numerical limitations in various categories. For these the Treaty on Conventional Armed Forces in Europe is an important precedent. 相似文献