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New computer program to calculate the symmetry of molecules

100%
Ashrafi A., Ahmadi M.
Open Chemistry
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2005
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vol. 3
|
issue 4
647-657
EN
In this paper we, present some MATLAB and GAP programs and use them to find the automorphism group of the Euclidean graph of the C80 fullerence with connectivity and geometry of Ih symmetry point group. It is proved that this group has order 120 and is isomorphic to Ih≊Z2×A5, where Z2 is, a cyclic group of order 2 and A5 is the alternating group on five symbols.
2
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The assessment of muscle strength symmetry in kayakers and canoeists

88%
Wietrzyński M., Mazur-Różycka J., Gajewski J., Michalski R., Różycki S., Buśko K.
Biomedical Human Kinetics
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2013
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vol. 5
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issue 1
65-71
EN
Study aim: To determine and compare the muscle strength profile and muscle strength symmetry of kayakers and canoeists. Material and methods: A total of 36 male participants participated in the study, including 25 kayakers and 9 canoeists. Measurements of maximum muscle torque were taken under static conditions for 10 muscle groups: flexors and extensors of the elbow, shoulder, knee, hip, and trunk. Muscle torque was allometrically scaled by body mass. To determine the muscle strength profiles of athletes in both disciplines, residual analysis was used. Two methods were utilized to assess and compare the muscle strength symmetry between left and right limbs. The first one is known as intraclass correlation coefficient (ICC). The second one is an asymmetry coefficient proposed by authors. Results: The study showed that kayakers obtained lower rates of asymmetry indicators than canoeists in most muscle groups. An overall asymmetry coefficient amounted to 0.77 ± 0.20 and 0.99 ± 0.31 (p < 0.05) for kayakers and canoeists, respectively. Moreover, it was observed that the kayakers and canoeists had similar strength profile. The symmetry assessment of maximum muscle torque corresponds to the characteristics of the studied disciplines. Conclusions: The intraclass correlation coefficient is recommended as a measure of strength symmetry for muscle groups comparisons. The asymmetry coefficient is recommended for comparison of individuals.
3
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The bilateral strength and power asymmetries in untrained boys

75%
Maly T., Zahalka F., Mala L., Cech P.
Open Medicine
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2014
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vol. 10
|
issue 1
EN
The aim of the study was to identify the level of isokinetic strength and power of lower limbs in 13-year- old untrained boys (n=22, height: 158.5±8.0 cm, mass: 49.1±12.6 kg), to determine bilateral deficit between the limbs in the tests and examine their mutual relationship. Maximum peak muscle torque of knee extensors (PTQ) and flexors (PTH) on dominant (DL) and non-dominant leg (NL) were measured by isokinetic dynamometer. Three types of a vertical jump: countermovement jump with (CMJFA) and without arms (CMJ) and squat jump (SJ) were performed on two force platforms. We found the significant effect (p<.01) of independent vari- ables (knee extensors, flexors, AV) and their interaction on PT. AV did not indicate any significant effect on bilat- eral ratio of knee extensors (F4,84=.74, p>.05, ηp2=0.03), however a significant effect of AV was found in knee flexors (F4,84=2.70,p<.05, ηp2=.114). The type of jump had no effect on the difference between force exerted by DL and NL (F1,21=.102, p>.05, ηp2=.01). Bilateral deficit (Q:Q, H:H) did not significantly correlate with bilateral deficit in jumps (p>.05). Despite the possibility of identifying muscle asymmetries in the sense of strength imbalances, their mutual relation- ship with results in isokinetic dynamometry and power jump tests is still unclear.
4
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THE APPLICABILITY OF USING PARAMETERS OF THE AUTOCORRELATION FUNCTION IN THE ASSESSMENT OF HUMAN BALANCE DURING QUIET BIPENDAL STANCE

75%
Stodółka J., Korzewa L., Stodółka W., Gambal J.
Central European Journal of Sport Sciences and Medicine
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2017
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vol. 17
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issue 1
79-87
EN
The purpose of the study was to analyze the parameters of the autocorrelation function when assessing time series ground reaction force (GRF) signals during quiet standing. GRF in the three directions were recorded on two Kistler force plates during three 15-s trials in a sample of 82 (31 females and 51 males) participants. Autocorrelation was performed on the GRF data and four parameters characterizing the function were computed. Comparisons of the right- and left-foot parameter means showed significant differences in mediolateral GRF for the time of the function's decay to 0, magnitude of the derivative output, and mean decay velocity to the extremum. Significant correlations were observed among all parameters – weak correlations between the time of the function's decay to 0 and the time to the first extremum and strong correlations between the derivative output and mean decay velocity to the extremum. The analyzed autocorrelation function parameters can serve as a precise measure of the motor control process during quiet standing. The strong correlations observed between the four parameters indicate that they evaluate similar properties of the central nervous system as a regulator of balance maintenance.
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