Validation of a Tennis Rating Score to evaluate the technical level of children tennis players

The purpose of this study was to create a valid and reliable assessment scale for the evaluation of three basic tennis strokes (forehand, backhand, serve) for 6–12-year-old tennis players, named the Tennis Rating Score for Children (TRSC). Altogether 60 players (21: forehand, 22: backhand, 17: serve) were video recorded (30 frames per second) while performing three main tennis strokes and later evaluated using the TRSC by five tennis trainers at Day 1 and Day 7. Agreement between days and raters was examined using the intraclass correlation coefficients (ICC). A Pearson’s correlation was calculated to determine convergent validity (score related to participant’s level of experience). The reliability between raters was very high for all three main strokes (ICC_FOREHAND = 0.874; ICC_BACKHAND = 0.877; ICC_SERVE = 0.877). The intra-rater test-retests ICCs were also very high (ICC_FOREHAND = 0.885; ICC_BACKHAND = 0.891; ICC_SERVE = 0.887). A large (r_FOREHAND = 0.660) and very large (r_BACKHAND = 0.730; r_SERVE = 0.772) Pearson’s correlations were found between all the ratings and the level of experience. The TRSC is shown to be highly reliable and valid when assessing technical skills in novice players, when compared to actual assessment from coaching experts; this tool may be helpful for tennis coaches to make a more objective diagnostic of the technical level of young tennis players.     

Imaginaries of Invention Management: Comparing Path Dependencies in East and West Germany

The ways in which societies and institutions institutionalize and practice invention management reflects not only how new ideas are valued, but also imaginaries about the role of science and technology for societal development. Often taking the US Bayh-Dole-Act as a model, many European states have recently implemented changes in how inventions at academic institutions are to be handled to optimize their societal impact. We analyze how these changes have been taken up—and made sense of—in regions with different pre-existing infrastructures, practices and semantics of invention management. For doing so, we build on a comparative analysis of continuities and changes in infrastructures, practices and semantics of invention management in North-Rhine Westphalia (NRW, a former Western state) and Saxony (a former GDR state) to reflect on how academic institutions have been handling inventions along transforming socio-political contexts. Building on document analysis and qualitative interviews with research managers, we discuss ongoing differences in practices of invention management and the semantic framing of the societal value of inventions in NRW and Saxony, and discuss how this can be understood before the background of their ideological, political and economic separation until reunification in 1990. Joining the conceptual perspectives of path dependencies and sociotechnical imaginaries, we argue that two critical incidents in the history of these states (the reunification in 1990 and a legal change in 2002) allowed for wide-ranging institutional alignments, but also allowed path dependencies in practices and semantics of invention management to prevail.     

Yugoslavia: other modernities,other histories

The Non-Aligned Movement was a transnational political project, a coalition of small and middle-sized states, mostly former colonies and developing countries, from the global south or the Third World. It was formed in 1961 in Yugoslavia at the Belgrade summit. The NAM represented the first major disruption in the Cold World map, a quest for alternative political alliances, for “alternative mundialization.” Culture was accorded particular importance in the NAM, despite the fact that it never took center-stage at summits and conferences. However, NAM’s cultural politics strongly condemned cultural imperialism and epistemic colonialism. Western (European) cultural heritage was to be understood in terms of “juxtaposition”; this heritage would be interwoven with and into the living culture of the colonized, and would not simply be repeated under new (political) circumstances. Consequently art and culture in the NAM were largely about politics and history, or to put it differently, they were a way of staking a claim to history. It seems the movement was somehow aware of the fact that this was the only way it could enter the world’s (cultural) space on an equal footing. There existed a heterogeneous artistic production, a variety of cultural politics and extensive cultural networks which enriched the cultural landscape of the NAM and enabled discussions about the meaning of art outside the Western canon.     

Spatial abilities during the circalunar cycle in both sexes

Spatial abilities vary during the menstrual cycle. The effects of a similar rhythm in men are unknown. Mental rotation and spatial visualization of young healthy volunteers (29 females and 31 males) were tested during the menstrual and periovulatory phase of the menstrual cycle in women, and during the low-testosterone and high-testosterone phases of the circatrigintan rhythm in men in random order. Men outperformed women in both tests. In women, higher scores were achieved during the periovulatory phase, in men during the low-testosterone phase. The correlation between actual salivary testosterone levels and spatial abilities were positive in women and negative in men. According to our knowledge, this is the first study showing effects of a male infradian rhythm on cognitive abilities.     

Market orientation in managing relationships with multiple constituencies of Croatian higher education

In this paper, market orientation in Croatian higher education (HE) is discussed within the context of stakeholder-oriented management. Drawing on existing studies, the ‘classical’ empirical model, describing the market orientation of generic nonprofit organisations, has been adapted to the contingencies of the Croatian HE sector. Empirical testing of the model, based on primary data drawn from the majority of public institutions of higher learning in the country, reveals inadequate market orientation toward the relevant stakeholders. Although social market orientation currently does not exist in Croatian HE institutions, the empirical results confirm that it might be possible to initiate a ‘virtuous circle’, in which relevant market orientation and stakeholder management practices, directed toward one or other of the stakeholders, simultaneously enhance orientation toward the other stakeholders. Unfortunately, the current situation in HE is not satisfactory, which could hinder the implementation of development of knowledge society in Croatia.

X-ray radiography and tomography for monitoring the penetration depth of consolidants in Opuka – the building stone of Prague monuments

Stone consolidation is one of the major restoration treatments used for historical monuments preservation. A natural stone is a complicated heterogeneous porous system making the process of consolidation dependent on many variables. In practical restoration aims, for a given stone type, the selection of a suitable consolidant and consolidation conditions therefore remains a complex issue. The impregnation depth is a key factor for the assessment of the treatment efficiency. The combination of state-of-the-art hybrid pixel semiconductor detectors with newly available micro-focus X-ray sources makes possible to apply X-ray radiography, an ideal non-destructive tool, for penetration depth monitoring. In this study, high-resolution X-ray radiography is used for monitoring the penetration depth of organosilicon consolidants in the Opuka stone. The penetration depth has been evaluated in relation to the time of consolidation, stone porosity and consolidation mixtures properties. The exact influence of the X-ray contrast agent on the consolidation depth has been investigated as well. The information obtained provides supplementary knowledge on the suitability of investigated products for the treatment of this type of stone. In our study, the capabilities of X-ray radiography have been demonstrated on X-ray radiography simple projections, high-resolution computed tomography (CT) as well as on the dynamic processes monitoring. The results thus can serve also as an instrumental and methodological example applicable for consolidation monitoring of other stone types.     

Measurement of fluid flow generated by artificial cilia

We observed and measured the fluid flow that was generated by an artificial cilium. The cilium was composed of superparamagnetic microspheres, in which magnetic dipole moments were induced by an external magnetic field. The interaction between the dipole moments resulted in formation of long chains-cilia, and the same external magnetic field was also used to drive the cilia in a periodic manner. Asymmetric periodic motion of the cilium resulted in generation of fluid flow and net pumping of the surrounding fluid. The flow and pumping performance were closely monitored by introducing small fluorescent tracer particles into the system. By detecting their motion, the fluid flow around an individual cilium was mapped and the flow velocities measured. We confirm that symmetric periodic beating of one cilium results in vortical motion only, whereas asymmetry is required for additional translational motion. We determine the effect of asymmetry on the pumping performance of a cilium, verify the theoretically predicted optimal pumping conditions, and determine the fluid behaviour around a linear array of three neighbouring cilia. In this case, the contributions of neighbouring cilia enhance the maximal flow velocity compared with a single cilium and contribute to a more uniform translational flow above the surface.