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This paper presents a detailed investigation of both normal and intruder states in 98Mo nucleus in the E ≥ 3 MeV. We considered all reported intruder energy levels for this nucleus, 0+2, 2+1, 4+1, 4+2, 2+2, and also the quadrupole transitions which originated from these levels. A mixing formalism based on the combination of U(5) and O(6) dynamical symmetries of the interacting boson model is used in the Hamiltonian and wavefunctions for, respectively, N- and (N + 2)-boson spaces. The weight of each space is determined by the calculation of theoretical quadrupole transition rates and compared with their experimental counterparts. By using these weights, the expectation values of the pure U(5) and O(6) Hamiltonians and also the total Hamiltonian that contains these limits and mixing terms are calculated for different levels, too. The results show that normal energy levels and quadrupole transition between them can be described satisfactory in comparison with experimental counterparts by using the pure U(5) Hamiltonian in the only N-boson space. For intruder levels and quadrupole transition originating from them or holding between normal and intruder states, the mixed formalism of Hamiltonian and wavefunctions increases the efficiency of theoretical formalisms and suggests exact results. [ABSTRACT FROM AUTHOR]

Background and Aim: Regard with the importance of balance in daily activities especially in sport activities and understanding the important factor affecting it, the purpose of this study was to compare the role of vision system on dynamic postural stability of young women with men elite athletes. Materials and Methods: Twenty six young women and men elite swimmer were chosen from the available society. They were divided in two groups according to body mass index. Each subject performed postural stability tests for 6 trials with open and close eyes (3 trials with open and 3 trial with close eyes) that each trial was taken for 30 seconds and with 10 seconds rest between each of them. Balance index in anterior- posterior and medial- lateral directions were calculated and independent t test was used to compare between groups. Result: Results show that men swimmer are more depended to vision than women swimmer in maintaining retrieval postural stability (p= 0.001), while most impairment in maintaining postural stability in both groups occur in lack of vision status in anterior- posterior direction (p= 0.001). Conclusion: The findings of this study can be used to design training programs to prepare athletes. Key words: balance, vision, athlete, control [ABSTRACT FROM AUTHOR]

Background and Aim: With regard to importance of the role of balance in performance of daily activity especially in exercise activity and necessary to identify the factors that influence the balance, the purpose of this study was to survey the effect of lower limb muscle fatigue on balance in elite young athletes. Materials and Methods: For this purpose, 15 young elite swimmers with a mean age and body mass index 17±0.7 and 21.62±0.5 during the two test phase, were studied. All participants performed the postural Stability and limit of stability tests in six for each test (three repetitions before and three repetitions after fatigue protocol by Wingate test)on the balance Biodex system. Values obtained by the system of the total, anterior - posterior, medial - lateral, anterior, anterior - right, anterior- left, posterior, posterior - right and posterior left index, were analyzed using paired sample t-test(P≤0.05). Results: Results showed that fatigue caused a significantly influence the anterior - posterior, medial - lateral, posterior, left and posterior -- left index. Conclusion: With considering the specificity of training principle, the results can be helpful in the design of exercises involving the lower limb muscles in the specific direction. [ABSTRACT FROM AUTHOR]