Ice hockey skating sprints: run to glide mechanics of high calibre male and female athletes

ABSTRACT

The skating acceleration to maximal speed transition (sprint) is an essential skill that involves substantial lower body strength and effective propulsion technique. Coaches and athletes strive to understand this optimal combination to improve performance and reduce injury risk. Hence, the purpose of this study was to compare body centre of mass and lower body kinematic profiles from static start to maximal speed of high calibre male and female ice hockey players on the ice surface. Overall, male and female skaters showed similar centre of mass trajectories, though magnitudes differed. The key performance difference was the male’s greater peak forward skating speed (8.96 ± 0.44 m/s vs the females’ 8.02 ± 0.36 m/s, p < 0.001), which was strongly correlated to peak leg strength (R ² = 0.81). Males generated greater forward acceleration during the initial accelerative steps, but thereafter, both sexes had similar stride-by-stride accelerations up to maximal speed. In terms of technique, males demonstrated greater hip abduction (p = 0.006) and knee flexion (p = 0.026) from ice contact to push off throughout the trials. For coaches and athletes, these findings underscore the importance of leg strength and widely planted running steps during the initial skating technique to achieve maximal skating speed over a 30 m distance.     

Philosophy of education in post-Soviet societies of Eastern Europe: Poland,Lithuania and Slovenia

This article explores the role of philosophy of education in three post-Soviet societies of Eastern Europe: Poland, Lithuania and Slovenia. The characteristic themes and approaches of philosophical reflection about education in these societies are explored with reference to three periods: the pre-Soviet, Soviet and post-Soviet periods.     

Preserving the Open Form. The Oskar and Zofia Hansen House in Szumin: Between architecture and contemporary art

A wooden summer house in Szumin, built between 1969 and 1970, is a spatial manifesto for the Open Form — a theory formulated by Polish architect, artist, and educator Oskar Hansen (1922–05). Oriented towards participation, process, and change in the hierarchy between the architect and the user, or the artist and the spectator, Hansen's theory formed a strong conceptual basis for his architectural, artistic, and pedagogical practice. Being a faithful expression of these ideas, the house is a spatio-temporal, transitional object, defined by constant adaptation to the changing needs of its users. In 2014 the property came into the custody of the Museum of Modern Art in Warsaw, Poland. A conservation strategy was developed to preserve both the idea and the physical aspect of the site. With its dominance of concept and artist's intent, this house has a stronger resemblance with a work of art than with built heritage. Therefore, the procedures developed for the conservation of contemporary artworks have been applied. These tools help to evaluate the range of necessary interventions and to set up a conservation programme.     

On the numerical competence of six-years-old children

The paper presents some of the results obtained in the course of experiments which have provided evidence of a considerable degree of numerical competence exhibited by six-years-olds and of their fairly advanced activity in discovering and dealing with arithmetical problems.The children used both counting and non-counting ways for solving arithmetical problems. They applied them elastically and interchangeably, often combining them into mutually complementary patterns of finding solutions.     

PROBLEMS OF EQUIVALENCE OF STUDIES AND DIPLOMAS IN HIGHER EDUCATION SYSTEMS

This article Surveys the problems and the traps of equivalences in higher education and proposes solutions to the former and ways of avoiding the latter. To begin with, one must be clear as to basic concepts and be able to distinguish between recognition and equivalence, the second being synonymous with the first, if formal equivalence is what is meant. But the principal task is one of defining and granting so‐called real equivalence, that is, equivalence based on the comparison of educational programmes, contents, length of study, the methods and the results of evaluations, and appropriate assessments of the academic value of practical work. It is also necessary to be clear at the outset as to the purposes of a given equivalence: to permit further study in another country or to aid in securing employment in a given occupation in another country. A major problem relates to varying conceptions of what is specifically university education in relation to higher education as a whole; the weight to be granted to post‐secondary, non‐university training; the whole question of length of studies; and ambiguities relative to terminology. Although it will never be possible to formulate ideal solutions to all problems, the key to obtaining the best possible solution is to be found in the improvement of the availability of standardized information by the exploitation of such sources as Unesco statistics, student books, analyses of bilateral conventions for applicable analogies, and, eventually, the sort of diploma supplement which Carin Berg and Ulrich Teichler are recommending.     

Plasma centrifugation does not influence thrombin-antithrombin and plasmin-antiplasmin levels but determines platelet microparticles count

Introduction

Centrifugation is an essential step for plasma preparation to remove residual elements in plasma, especially platelets and platelet-derived microparticles (PMPs). Our working hypothesis was that centrifugation as a preanalytical step may influence some coagulation parameters.

Materials and methods

Healthy young men were recruited (N = 17). For centrifugation, two protocols were applied: (A) the first centrifugation at 2500 x g for 15 min and (B) at 2500 x g for 20 min at room temperature with a light brake. In protocol (A), the second centrifugation was carried out at 2500 x g for 15 min, whereas in protocol (B), the second centrifugation involved a 10 min spin at 13,000 x g. Thrombin-antithrombin (TAT) and plasmin-antiplasmin (PAP) complexes concentrations were determined by enzyme-linked immunosorbent assays. PMPs were stained with CD41 antibody and annexin V, and analyzed by flow cytometry method. Procoagulant activity was assayed by the Calibrated Automated Thrombogram method as a slope of thrombin formation (CAT velocity).

Results

Median TAT and PAP concentrations did not differ between the centrifugation protocols. The high speed centrifugation reduced the median (IQR) PMP count in plasma from 1291 (841-1975) to 573 (391-1010) PMP/µL (P = 0.001), and CAT velocity from 2.01 (1.31-2.88) to 0.97 (0.82-1.73) nM/min (P = 0.049). Spearman’s rank correlation analysis showed correlation between TAT and PMPs in the protocol A plasma which was (rho = 0.52, P < 0.050) and between PMPs and CAT for protocol A (rho = 0.74, P < 0.050) and protocol B (rho = 0.78, P < 0.050).

Conclusion

Centrifugation protocols do not influence the markers of plasminogen (PAP) and thrombin (TAT) generation but they do affect the PMP count and procoagulant activity.Key words: cell-derived microparticles, blood coagulation tests, centrifugation, preanalytical phase