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Henryk Duda

Cognitive support in teaching football techniques

Study aim: To improve the teaching of football techniques by applying cognitive and imagery techniques.

Material and methods: Four groups of subjects, n = 32 each, were studied: male and female physical education students aged 20 - 21 years, not engaged previously in football training; male juniors and minors, aged 16 and 13 years, respectively, attending mastery School of Sports (football); their training experience amounted to 6 and 3 years, respectively. Every group was divided into two subgroups (n = 16 each) - control and experimental. All subjects underwent a course consisting of 40 sessions lasting 90 min each, once weekly. Before and at the end of study period the participants were subjected to 3 specific tests assessing their knowledge, motor fitness and game skills.

Results: Subjects from all experimental groups achieved significantly (mostly p<0. 001) better results than the respective control groups in all three areas - knowledge, motor fitness and game skills. The levels of acquired knowledge significantly (p<0. 05 - 0. 001) correlated with specific motor fitness and game skills in all groups of subjects.

Conclusions: Cognitive approach improves the results teaching football techniques and may serve as a valuable tool in training.

Open access

Waclawa Marcoin, Henryk Duda and Dariusz Chrobak

Properties of solid dispersions of selected magnesium salts and the absorption process of Mg2+ ions in vitro

The paper presents an application of phosphatidylcholine 45% (PC 45) and polyvinylpyrrolidone (PVP) in formulations of magnesium salts such as Mg(VitB6) and Mg(VitB6Arg) prepared by solid dispersion (SD) techniques. The evaluation of influence of the selected carriers on some physicochemical properties of solid dispersions and on the absorption process of Mg +2 ions in vitro were made. An infrared (IR) spectra study suggested creation of a hydrogen bond between the carriers and the examined magnesium salts. The results of the following thermal analysis: differential thermal analysis (DTA), thermogravimetry (TG), and differential scanning calorimetry (DSC) showed that application of PVP into SD lower the temperature of the decomposition process. However, in the case of PC 45 into SD the characteristic thermal effects of higher temperatures were observed. Moreover, values of the enthalpy SD of decomposition process were decreased. The results of these studies on absorption process of Mg2+ ions in vitro showed the positive influence of the applied carriers on the partition coefficient values (log P) in the examined formulation.

Open access

Tadeusz Groń, Magdalena Piątkowska, Elżbieta Tomaszewicz, Bogdan Sawicki, Piotr Urbanowicz and Henryk Duda


Polycrystalline samples of new scheelite-type tungstates, Pb1−3x xPr2xWO4 with 0.0098 ⩽ x ⩽ 0.20, where denotes cationic vacancies have been successfully prepared by a high-temperature solid-state reaction method using Pr2(WO4)3 and PbWO4 as the starting reactants. The influence of the Pr3+ substitution in the scheelite framework on the structure and optical properties of prepared new ceramic materials has been examined using powder X-ray diffraction method (XRD) and UV-Vis-NIR spectroscopy. The results of dielectric studies of Pb1−3x xPr2xWO4 samples showed both low values of dielectric constant (below 14) and loss tangent (below 0.2). The electrical conductivity and thermoelectric power measurements revealed a low conductivity (∼2 × 10−9 S/m) and the sign change of thermoelectric power around the temperature of 366 K suggesting the p-n transition. These results are discussed in the context of vacancy, acceptor and donor levels as well as the Maxwell-Wagner model.