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101.
Person–environment interactions might ultimately drive longer term development. This experience sampling study (Data collection: 2019/20 the Netherlands) assessed short-term linkages between parent–adolescent interaction quality and affect during 2281 interactions of 124 adolescents (Mage = 15.80, SDage = 1.69, 59% girls, 92% Dutch, Education: 25% low, 31% middle, 35% high, 9% other). Adolescents reported on parent–adolescent interaction quality (i.e., warmth and conflict) and momentary positive and negative affect five to six times a day, for 14 days. Preregistered dynamic structural equation models (DSEM) revealed within-family associations between parent–adolescent interaction quality and adolescent affect (concurrently: = −.22 to .39; lagged effects: ß = −.17 to .15). These effects varied significantly between families. These findings stress the need for more person-specific research on parenting processes.  相似文献   
102.

Instructional videos are widely used to study teachers’ professional vision. A new technological development in video research is mobile eye-tracking (MET). It has the potential to provide fine-grained insights into teachers’ professional vision in action, but has yet been scarcely employed. We addressed this research gap by using MET video feedback to examine how expert and novice teachers differed in their noticing and weighing of alternative teaching strategies. Expert and novice teachers’ lessons were recorded with MET devices. Then, they commented on what they observe while watching their own teaching videos. Using a mixed methods approach, we found that expert and novice teachers did not differ in the number of classroom events they noticed and alternative teaching strategies they mentioned. However, novice teachers were more critical of their own teaching than expert teachers, particularly when they considered alternative teaching strategies. Practical implications for the field of teacher education are discussed.

  相似文献   
103.
Instructional Science - Extensive research has established that successful learning from an example is conditional on an important learning activity: self-explanation. Moreover, a model for...  相似文献   
104.
This paper deals with the problem of constrained stability and tracking of Takagi–Sugeno (T–S) fuzzy positive systems. Linear programming (LP) is used to insert the constraints in the design phase while imposing positivity in closed-loop. The theoretical results are applied to the buck DC–DC converter which is widely used in the photovoltaic generators. Based on the simulation results success of the method is shown for this application.  相似文献   
105.
Microfluidic devices allow for the production of physiologically relevant cellular microenvironments by including biomimetic hydrogels and generating controlled chemical gradients. During transport, the biomolecules interact in distinct ways with the fibrillar networks: as purely diffusive factors in the soluble fluid or bound to the matrix proteins. These two main mechanisms may regulate distinct cell responses in order to guide their directional migration: caused by the substrate-bound chemoattractant gradient (haptotaxis) or by the gradient established within the soluble fluid (chemotaxis). In this work 3D diffusion experiments, in combination with ELISA assays, are performed using microfluidic platforms in order to quantify the distribution of PDGF-BB and TGF-β1 across collagen and fibrin gels. Furthermore, to gain a deeper understanding of the fundamental processes, the experiments are reproduced by computer simulations based on a reaction-diffusion transport model. This model yields an accurate prediction of the experimental results, confirming that diffusion and binding phenomena are established within the microdevice.  相似文献   
106.
The undulatory underwater sequence is one of the most important phases in competitive swimming. An understanding of the recurrent vortex dynamics around the human body and their generation could therefore be used to improve swimming techniques. In order to produce a dynamic model, we applied human joint kinematics to three-dimensional (3D) body scans of a female swimmer. The flow around this dynamic model was then calculated using computational fluid dynamics with the aid of moving 3D meshes. Evaluation of the numerical results delivered by the various motion cycles identified characteristic vortex structures for each of the cycles, which exhibited increasing intensity and drag influence. At maximum thrust, drag forces appear to be 12 times higher than those of a passive gliding swimmer. As far as we know, this is the first disclosure of vortex rings merging into vortex tubes in the wake after vortex recapturing. All unsteady structures were visualized using a modified Q-criterion also incorporated into our methods. At the very least, our approach is likely to be suited to further studies examining swimmers engaging in undulatory swimming during training or competition.  相似文献   
107.
Abstract

Anticipatory postural adjustments (APAs), i.e. preparatory positioning of the head, the trunk and the foot, are essential to initiate cutting manoeuvres during football games. The aim of the present study was to determine how APA strategies during cutting manoeuvres are influenced by a reduction of the time available to prepare the movement.

Thirteen football players performed different cutting tasks, with directions of cutting either known prior to the task or indicated by a light signal occurring 850, 600 or 500 ms before ground contact.

With less time available to prepare the cutting manoeuvre, the head was less orientated towards the cutting direction (P = 0.033) and the trunk was even more rotated in the opposite direction (P = 0.002), while the foot placement was not significantly influenced. Moreover, the induced higher lateral trunk flexion correlated with the increased knee abduction moment (r = 0.41; P = 0.009).

Increasing lateral trunk flexion is the main strategy used to successfully perform a cutting manoeuvre when less time is available to prepare the movement. However, higher lateral trunk flexion was associated with an increased knee abduction moment and therefore an increased knee injury risk. Reducing lateral trunk flexion during cutting manoeuvres should be part of training programs seeking the optimisation of APAs.  相似文献   
108.
Erinnerungskultur (culture of remembrance) is a widely discussed notion in German historiography. First, the meaning of Erinnerungskultur, including the specific role of academic historiography of sport, is described and explained with respect to sport and sport historiography. One main objective is to reveal the diversity of cultures of sport history and the specific obligations of academic historiography. Second, the actors of sport memories and/or Traditionspflege (heritage) are characterised, and, third, some controversial and perennial debates that permeate German sports history are explained and interpreted, especially that of Carl Diem, internationally known as ‘Mister Olympics’ of 1936. All in all, the paper provides an overview of the mainstreams, cultures and politics of history in Germany with respect to sport.  相似文献   
109.
Intellectual engagement (IE) refers to enjoyment of intellectual activities and is proposed as causal for knowledge acquisition. The role of IE for cognitive development was examined utilizing 2‐year longitudinal data from 112 ninth graders (average baseline age: 14.7 years). Higher baseline IE predicted higher baseline crystallized ability but not changes therein, and was not associated with fluid ability. Furthermore, IE predicted change in school grades in language but not in mathematics grades or in standardized tests. These findings suggest that IE is not a major predictor of knowledge acquisition in adolescence, where degree of self‐determination in intellectual behaviors may be relatively limited. Open questions for future research are addressed, including reciprocal longitudinal associations between IE and academic and cognitive development.  相似文献   
110.
One main focus of teacher education research concentrates on teachers’ pedagogical content knowledge (PCK). It has been shown that teachers’ PCK correlates with teaching effectiveness as well as with students’ achievement gains. Teachers’ PCK should be analyzed as one of the main important components to evaluate professional development programs. On this account, it is necessary to develop standardized measures of biology teachers’ topic-specific PCK that are labor-efficient. This paper presents a study on the development, evaluation, and validation of a paper-and-pencil test to measure biology teachers’ declarative PCK on the topic of blood and the human cardiovascular system. The development of the test was based, among other considerations, on a review of research literature on PCK and an analysis of 50 videotaped biology lessons. The final test instrument was comprised of 15 items distributed across 2 scales. The findings of the main study—with 93 preservice and in-service biology teachers and 12 biologists—confirmed that this measure of biology teachers’ declarative PCK was reliable, objective, and valid. In-service biology teachers scored higher on the test than preservice teachers (effect size Cohen’s d, 0.65) on one hand and, also, than biologists (Cohen’s d, 1.00) on the other hand. Future versions of this test should explore enlarging the scales and measuring procedural aspects of PCK.  相似文献   
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