درخت حوزه‌های تخصصی

Introduction: This study was conducted to control hand tremors and decrease adverse effects due to the high field intensity in advanced Parkinson’s disease. We aimed at concurrently controlling two areas of Basal Ganglia (BG) in a closed-loop strategy.Methods: In the present research, two nuclei of BG, namely subthalamic nucleus and globus pallidus internal were simultaneously controlled. Furthermore, to enhance the feasibility of the suggested control strategy, the coefficients of the controller were determined using a hybrid version of the harmony search and cuckoo optimization algorithm. Results: The advantages of the applied method include decreasing hand tremors and applied electric field intensity to the brain; consequently, it leads to reducing adverse effects, such as muscle contraction and speech disorders. Moreover, the purposed controller has achieved superior performance against changing the parameters of the model (robustness analysis) and under noise tests, compared to other conventional controllers, such as Proportional Integrator (PI) and Proportional Derivative (PD).Conclusion: The employed approach provided an effective strategy to reduce hand tremors. It also decreased the delivered high field intensity to the brain; consequently, it reduced adverse effects, such as memory loss and speech disorders. It is important to ascertain the superior performance of the suggested closed-loop control scheme in different conditions and levels of tremor. Such a function was examined in terms of robustness against the variation of parameters and uncertainties. We also obtained time domain outcomes, i.e., compared with the state-of-the-art approaches.

Psychological variables that affect mental health are divided into useful and harmful variables. Useful variables are beneficial for improving mental health and quality of life, and increasing well-being, for instance, happiness, calmness, vigor, and mental toughness. Harmful variables reduce mental health, quality, and enjoyment of life, for example, negative mood states, anxiety, and burnout. This study aimed to predict psychological burnout based on mood states and mental toughness of elite athletes with physical disabilities. Participants have included 150 athletes with physical disabilities (77women; 73men) competing at national or international Paralympic sports teams (mean age=42.34 ±7.44y, mean experience=8.38 ± 3.19 y) that were selected in the random method. Participants accomplished the Athlete Burnout Questionnaire, the 32-item Brunel Mood Scale, and the Sports Mental Toughness Questionnaire. Stepwise multiple linear regression analysis showed that happiness (moderate negative power, 51%), vigor (weak negative power, 28%), fatigue (weak positive power, 22%), mental toughness (medium negative power, 57%), and confidence (weak negative power, 29%) were able to predict the total burnout of the athletes with disabilities. These findings are essential for psychologists since developing and increasing the useful variables and inhibiting or decreasing the harmful variables for mental health can prevent sports burnout.

Background and Purpose: Increasing participation in sports activities has increased the incidence of sports injuries. Considering the short and long term complications of sports injuries, the need to prevent them is one of the most important goals. The purpose of this study was to evaluate the effects of ankle bracing on the ankle plantar flexor muscles activity in different foot position during drop landing with and without fatigue. Method: Fourteen female college athletes participated in this study. Five models of 5 and 10 degrees medial, lateral and normal wedged insoles were used to simulate the position of the feet on the ground at the wrong landing technique. The Medial Gastrocnemius (MG) and Peroneus Longus (PL) muscles activity 100 ms before and 100ms after landing in different foot position before and after muscles fatigue with and without ankle bracing was recorded with surface electromyography. Repeated measures ANOVA was used for statistical analysis (p≤0.05). Results: The results showed that the effect of time on the activity of MG and PL muscles in landing with brace was significant, so that the MG muscle before landing and PL muscle after landing had a higher activity in both times before and after fatigue (p≤0.001). The activity of this muscles was not significant when using the ankle brace during landing in different positions (p˃0.05). Conclusions: According to the results of this study, lace-up brace can help to increase muscles activity when they were fatigue, while the using of brace does not affect muscle activity when landing perform in different positions without fatigue. According to the results, In the case of a suggestion to use brace for athletes, all aspects of using this equipment should be considered.