The Effect of Corrective Feedback Exercise on Knee Kinematics and EMG of Lower Limbs of Female Wushu Players

Introduction: Recent studies have examined the risk factors associated with lower limb injuries. This study aimed to explore the effect of 12 sessions of feedback corrective exercises on the kinematic indicators of the knee and the Electromyography Activity (EMG) of the muscles of the lower limbs of female wushu players. The present study has a quasi-experimental design with a pre-test/post-test design and a control group. Materials and Methods: In this study, 16 female wushu players were selected by the available sampling method and placed in two groups of exercise and control. The exercise group performed feedback correction exercises for 12 sessions. Before and after the knee varus exercises, we measured, pelvic drop, and EMG of the lower limb muscles of both groups in the SLS movement. The independent two-sample t-test was used to examine intergroup differences and the two-group correlated t-test was used to compare intra group sizes. To analyze the statistical data, SPSS V. 23 was used (P≤0.05) Results: The results showed a significant difference in knee varus between the experiment group and the control group in the pre-test and there was a significant difference between the pelvic drop in the pre-test and post-test of the experiment group compared with the control. The angle of the knee varus in the exercise group showed a significant difference with the control group. The EMG results of the muscles in the pre-test and post-test were significantly different. Conclusion: Based on the findings of the present study, the feedback correction exercise may improve motion control in wushu players. It also improved neuromuscular weakness in the subjects. According to the results and based on less muscle activity during movements, this exercise will reduce fatigue and the risk of injury.

Parental Stress Provoked by Short-Term School Closures During the Second COVID-19 Lockdown

Governments of numerous countries implemented school closures to contain the COVID-19 pandemic. Several investigations have shown the negative impact of social-distancing policies and school closures on children worldwide. Recently, research also demonstrated adverse effects on adults’ well-being. The development of children is strongly affected by their parent’s emotional state. The present study aimed to examine parental stress levels caused by a short period of homeschooling in December 2020 in Germany. A structured survey was set up and distributed randomly via social media and parent associations. We observed a significant increase in stress and concerns. Family conflicts significantly increased, social isolation was feared, and powerlessness and helplessness ascended. Risk factors were parental education levels, parental working time, and teaching features like the frequency of feedback, correction, and accessibility.

Development and Validation of Electronic Stability Control System Algorithm Based on Tire Force Observation

In view of the higher and higher assembly rate of the electronic stability control system (ESC in short), the control accuracy still needs to be improved. In order to make up for the insufficient accuracy of the tire model in the nonlinear area of the tire, in this paper, an algorithm for the electronic stability control system based on the control of tire force feedforward used in conjunction with tire force sensors is proposed. The algorithm takes into consideration the lateral stability of the tire under extreme conditions affected by the braking force. We use linear optimal control to determine the optimal yaw moment, and obtain the brake wheel cylinder pressure through an algorithm combining feedforward compensation based on measured tire force and feedback correction. The controller structure is divided into two layers, the upper layer is controlled by a linear quadratic regulator (LQR in short) and the lower layer is controlled by PID (Proportional-integral-derivative) and feedforward. After that, verification of the controller’s algorithms using software cosimulation and hardware-in-the-loop (HIL in short) testing in the double lane change (DLC in short) and sine with dwell (SWD in short) conditions. From the test results it can be concluded that the controller based on tire force observation has partially control advantages.

Gut-to-brain signals in feeding control

Interoceptive signals from gut and adipose tissue and sensory cues from the environment are integrated by hubs in the brain to regulate feeding behavior and maintain homeostatic control of body weight. In vivo neural recordings have revealed that these signals control the activity of multiple layers of hunger neurons and that eating is not only the result of feedback correction to a set point, but can also be under the influence of anticipatory regulations. A series of recent technical developments have revealed how peripheral and sensory signals in particular from the gut are conveyed to the brain to integrate neural circuits. Here, we describe the mechanisms involved in gastrointestinal stimulation by nutrients and how these signals act on the hindbrain to generate motivated behaviors. We also consider the organization of multidirectional intra- and extra-hypothalamic circuits and how this has created a framework for understanding neural control of feeding.