Creatine kinase,myosin heavy chains and magnetic resonance imaging after eccentric exercise     

Stephan Sorichter  Johannes Mair  Arnold Koller  Erich Muller  Christian Kremser  Werner Judmaier 《Journal of sports sciences》2013,31(9):687-691

The aim of this study was to examine the relationship between myosin heavy chain (MHC) release as a specific marker of slow-twitch muscle fibre breakdown and magnetic resonance imaging (MRI) of skeletal muscle injury after eccentric exercise. The effects of a single series of 70 high-intensity eccentric contractions of the quadriceps femoris muscle group (single leg) on plasma concentrations of creatine kinase and MHC fragments were assessed in 10 young male sport education trainees before and 1 and 4 days after exercise. To visualize muscle injury, MRI of the loaded thigh was performed before and 4 days after the eccentric exercise. All participants recorded an increase ( P ? 0.05) in creatine kinase after exercise. In five participants, T2 signal intensity was unchanged post-exercise compared with pre-exercise and MHC plasma concentration was normal; however, they showed an increase ( P ? 0.05) in creatine kinase after exercise. For the remaining five participants, there was an increase in T2 signal intensity of the loaded vastus intermedius and vastus lateralis. These changes in MRI were accompanied by an increase in MHC plasma concentration ( P ? 0.01) as well as an increase in creatine kinase ( P ? 0.01). We suggest that changes in MRI T2 signal intensity after muscle damage induced by eccentric exercise are closely related to damage to structurally bound contractile filaments of some muscle fibres. Additionally, MHC plasma release indicates that this damage affects not only fast-twitch fibres but also some slow-twitch fibres.  相似文献   

Combining verbal and visual cueing: Fostering learning pictorial content by coordinating verbal explanations with different types of visual cueing     

Glaser  Manuela  Schwan  Stephan 《Instructional Science》2020,48(2):159-182

Instructional Science - Multimedia learning scenarios in which a picture is the main focus often use combinations of verbal and visual cueing. Based on models of picture processing and multimedia...  相似文献   

What do we learn from docutainment? Processing hybrid television documentaries   总被引：1，自引：0，他引：1  

Manuela Glaser  Bärbel Garsoffky Stephan Schwan 《Learning and Instruction》2012,22(1):37-46

This study examined how hybrid documentary formats, which embed educational contents into narratives, are cognitively processed. Based on existing research and theories, two reception modes were identified: processing with a focus on the narrative plotline and processing with a focus on the thematic structure. In two experiments, two markers of narrative processing could be found for hybrid television documentaries: the experience of transportation and the narrative distance effect. In the first experiment, it could be shown that re-enactments and personal variables enhance the experience of transportation. The second experiment confirmed the narrative distance effect, which occurs independently of reception goals. This means that educational facts which are closely tied to the narrative plotline were learned better than distant facts, regardless of whether the recipients watched the documentary for information or entertainment purposes. The study supplements prior theories on hybrid processing and provides conditions under which narratives are appropriate for learning.  相似文献   

Communities of Public Service Support: Citizens engage in social learning in peer-to-peer networks     

Albert Meijer  Stephan GrimmelikhuijsenGijs Jan Brandsma 《Government Information Quarterly》2012,29(1):21-29

New Public Management and bureaucratic models fail to acknowledge the value of peer-to-peer cooperation between citizens as a resource for public service support. Social media enable citizens to create environments for sharing information about public services in Communities of Public Service Support. The success of this model for public service support depends on the availability of communities, the level of active participation, and the information content. This paper presents an empirical study of virtual communities of expats in The Netherlands. Our analysis shows that there is a wide variety of virtual expat communities with a high level of participation and valuable content. We conclude that virtual communities play an important role in public service support since they facilitate social learning between citizens.  相似文献   

Training the use of interactive videos: effects on mastering different tasks     

Martin Merkt  Stephan Schwan 《Instructional Science》2014,42(3):421-441

This study was concerned with identifying prerequisites for the successful use of videos that offer different levels of interactivity. In a homework scenario, 64 ninth graders participated either in a search training demonstrating the efficient use of features facilitating the selection of relevant information or in a control training focusing on the integration of new information with prior knowledge. Following the training, the participants used either a common video that allowed them to control the transient flow of the information via stop and browsing or an enhanced video that additionally facilitated the localization of information via chapter selection and an index. Overall, the students wrote two essays (Essay 1: summary; Essay 2: argument) and performed a search task. The study revealed that, independent of the training condition, students benefitted from the enhanced video for the search task which merely required naming isolated facts. Moreover, in a summary task, the enhanced video resulted in the consideration of information from more different chapters when the task required gathering information from the video; however, this broader consideration of chapters only translated into naming more information after the search training. The data of a second essay requiring inferences about the video’s contents (argument) were not analyzed due to a floor effect. Taken together, these results indicate that the characteristics of a task as well as the students’ knowledge of respective search strategies need to be considered when implementing interactive features in video environments.  相似文献   

The Bertelsmann AG: An Exploratory Case Study on Synergy Management in a Globally Acting Media Organization     

Bernd Schulze  Bodo Thielmann  Stephan Sieprath  Thomas Hess 《媒体管理杂志》2013,15(3-4):138-147

By the multiple usage of immaterial resources across organizational and national market borders, globally acting media conglomerates are able to achieve outstanding synergies. For this reason, they are expected to realize higher margins of profit than smaller-size, nondiversified media firms. However, no empirical evidence has been found for a positive correlation between a firm's size or its presence in many businesses of the media industry and its economic performance until now. Consequently, possible synergies do not seem to be fully exploited in many cases. This article analyzes how to institutionalize and implement synergy management in decentralized media organizations. For these purposes, we first develop a basic understanding and then conduct an exploratory case study on Bertelsmann's approach, which overcomes the stress ratio between corporate coordination and independent action at the operational level. Distinguishing various product types and triggers, this case study renders the process of synergy management more precisely and illustrates how to arrange responsibilities between organizational units. Finally, by relating the results of the case study to the body of literature, we work out patterns of responsibility assignment and drivers of success for strategic integration. In contrast to operational integration, the latter may lead to synergies due to cross-divisional cooperation and business development.  相似文献   

K-12 Students' Perceptions of Scientists: Finding a valid measurement and exploring whether exposure to scientists makes an impact     

Susan J. Hillman  Kylie H. Bloodsworth  Charles E. Tilburg  Stephan I. Zeeman  Henrietta E. List 《International Journal of Science Education》2013,35(15):2580-2595

This study was launched from a National Science Foundation GK-12 grant in which graduate fellows in Science, Technology, Engineering, and Mathematics (STEM) are placed in classrooms to engage K-12 students in STEM activities. The investigation explored whether the STEM Fellows' presence impacted the K-12 students' stereotypical image of a scientist. Since finding a valid instrument is critical, the study involved (1) determining the validity of the commonly administered Draw-A-Scientist Test (DAST) against a newly designed six-question survey and (2) using a combination of both instruments to determine what stereotypes are currently held by children. A pretest–posttest design was used on 485 students, grades 3–11, attending 6 different schools in suburban and rural Maine communities. A significant but low positive correlation was found between the DAST and the survey; therefore, it is imperative that the DAST not be used alone, but corroboration with interviews or survey questions should occur. Pretest results revealed that the children held common stereotypes of scientists, but these stereotypes were neither as extensive nor did they increase with the grade level as past research has indicated, suggesting that a shift has occurred with children having a broader concept of who a scientist can be. Finally, the presence of an STEM Fellow corresponded with decreased stereotypes in middle school and high school, but no change in elementary age children. More research is needed to determine whether this reflects resiliency in elementary children's perceptions or limitations in either drawing or in writing out their responses.  相似文献   

Learning about persons: the effects of text structure and executive capacity on conceptual change     

Christiane Baadte  Stephan Dutke 《European Journal of Psychology of Education - EJPE》2013,28(3):1045-1064

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Measuring teaching quality: some key issues     

Skedsmo  Guri  Huber  Stephan Gerhard 《Educational Assessment, Evaluation and Accountability》2019,31(2):151-153

Educational Assessment, Evaluation and Accountability -  相似文献   

Reliability,validity and fairness—key issues in assessing the quality of teaching,instructional leadership and school practice     

Guri Skedsmo  Stephan Gerhard Huber 《Educational Assessment, Evaluation and Accountability》2018,30(4):343-346

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