On-chip three-dimensional cell culture in phaseguides improves hepatocyte functions in vitro

The in vitro study of liver functions and liver cell specific responses to external stimuli deals with the problem to preserve the in vivo functions of primary hepatocytes. In this study, we used the biochip OrganoPlate^TM (MIMETAS) that combines different advantages for the cultivation of hepatocytes in vitro: (1) the perfusion flow is achieved without a pump allowing easy handling and placement in the incubator; (2) the phaseguides allow plating of matrix-embedded cells in lanes adjacent to the perfusion flow without physical barrier; and (3) the matrix-embedding ensures indirect contact of the cells to the flow. In order to evaluate the applicability of this biochip for the study of hepatocyte''s functions, Matrigel^TM-embedded HepG2 cells were cultured over three weeks in this biochip and compared to a static Matrigel culture (3D) and a monolayer culture (2D). Chip-cultured cells grew in spheroid-like structures and were characterized by the formation of bile canaliculi and a high viability over 14 days. Hepatocyte-specific physiology was achieved as determined by an increase in albumin production. Improved detoxification metabolism was demonstrated by strongly increased cytochrome P450 activity and urea production. Additionally, chip-cultured cells displayed increased sensitivity to acetaminophen. Altogether, the OrganoPlate seems to be a very useful alternative for the cultivation of hepatocytes, as their behavior was strongly improved over 2D and static 3D cultures and the results were largely comparable and partly superior to the previous reports on biochip-cultured hepatocytes. As for the low technical needs, this platform has the appearance of being highly applicable for further studies of hepatocytes'' responses to external stimuli.     

Psychometric properties of the motor diagnostics in the German football talent identification and development programme

The utilisation of motor performance tests for talent identification in youth sports is discussed intensively in talent research. This article examines the reliability, differential stability and validity of the motor diagnostics conducted nationwide by the German football talent identification and development programme and provides reference values for a standardised interpretation of the diagnostics results. Highly selected players (the top 4% of their age groups, U12–U15) took part in the diagnostics at 17 measurement points between spring 2004 and spring 2012 (N = 68,158). The heterogeneous test battery measured speed abilities and football-specific technical skills (sprint, agility, dribbling, ball control, shooting, juggling). For all measurement points, the overall score and the speed tests showed high internal consistency, high test–retest reliability and satisfying differential stability. The diagnostics demonstrated satisfying factorial-related validity with plausible and stable loadings on the two empirical factors “speed” and “technical skills”. The score, and the technical skills dribbling and juggling, differentiated the most among players of different performance levels and thus showed the highest criterion-related validity. Satisfactory psychometric properties for the diagnostics are an important prerequisite for a scientifically sound rating of players’ actual motor performance and for the future examination of the prognostic validity for success in adulthood.     

Individual predictors of adolescents’ vocational interest stabilities

The study investigated the predictive utility of interest profile differentiation, coherence, elevation, congruence, and vocational identity commitment and career maturity (career planning and exploration) on the 10-month interest stability of 292 Swiss eighth-grade students: profile, rank, and level stabilities were assessed. Controlling for socio-demographic and vocational interest type variables, measures of differentiated and coherent vocational interests were significant predictors of profile stability. Interest elevation predicted more rank and level stability. The career development variables explained only a non-significant additional amount of variance in the different stability measures.     

Generierung interaktiver Animationen von Berechnungsmodellen

In diesem Artikel werden zwei generative Ans?tze für animierte Berechnungsmodelle vorgestellt und im Kontext von Lernsoftware für den Compilerbau angewandt. Zuerst wird eine Implementierung für den ersten Ansatz beschrieben. Basierend auf der Erfahrung mit diesem Prototypen wurde der zweite Ansatz entwickelt und das Ganimal Rahmenwerk entworfen. Es handelt sich dabei um ein generisches Algorithmenanimationssystem, das eine für ein solches System einzigartige Fülle an M?glichkeiten durch sein graphisches Basispaket, das nebenl?ufige Laufzeitsystem mit graphischer Benutzeroberfl?che und die Programmier- und Animationsbeschreibungssprache Ganila bietet.     

Informationen des Deutschen Olympischen Sportbunds (DOSB)

DOSB-Informationen

Informationen des Deutschen Olympischen Sportbunds (DOSB)     

Ein Beitrag zur systematischen Sportgeräteentwicklung

Sporting goods companies face significant challenges. As a result, the importance of a structured and systematic product development process has increased. There are several paradigms to support the product development, with the integrated product development paradigm as one of the most important ones. This study aims at the verification of an efficient application of Integrated Product Development for the development of sports equipment. For that purpose Insider Action Research is used. Three different case studies (leisure, fun and professional sports market) were conducted and analysed. To objectify the results, objective and subjective efficiency criteria were defined. The results show a positive evaluation of the criteria. So far, the development projects have been performed in an academic context only.     

Vielseitigkeit als Ausbildungsstrategie im leistungssportlichen Nachwuchstraining

This paper presents an excerpt from a comprehensive study on the concepts of long-term athlete development. Following a qualitative research methodology and using a hermeneutic-reconstructive procedure the purpose of this paper was to gain insight into expert youth sports coaches’ understanding of the two main trajectories leading to elite performance: early specialization and early sampling. Analysis of the transcribed interviews suggests that the training strategy is primarily the result of a complex decision making process. Additionally, coaches perceived a trend towards early specialization which conflicts with existing considerations of long-term athlete development. The results of this study provide an opportunity to understand the subject of diversification in youth sports and to raise awareness for the problems of practitioners.     

Rejoinder in Defense of the Standard model of the Mind: From Whimsical to Systematic Science

This rejoinder discusses the issues raised by the three commentators of the target article. In agreement with Hunt, it is accepted that, as any overarching theory in any science, it does involve postulates about the mind that must be scrutinized by further research. However, its main postulates are well supported by the findings of specifically designed experiments. In response to Olson, it is maintained that this theory, as an integration of the standard models of the human mind in cognitive, psychometric, and differential psychology, deals better than its competitors with educationally important questions about what, how, and when to teach important knowledge. In fact, the mechanisms of specified understanding are refined enough to explicate what meaning making is possible at different ages. In agreement with Anderson, it is noted that the theory may direct curriculum developers how to develop the curriculum in different subjects and teachers colleges how to educate teachers so that learning in the classroom may become deeper, more stable, and transferable, thereby increasing the understanding and learning autonomy of students.