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Qinghai-Tibet Plateau is one of the regions with the strongest crustal tectonic movement in the world due to its special continental tectonic location. There are many large active faults in the block and its surrounding areas, which are prone to strong earthquakes. The area is also a natural test site for studying the mechanism of plate tectonic movement in the continent. Global Positioning System(GPS)is widely used in the study of crustal deformation monitoring due to its high temporal and spatial resolution, wide coverage, and high observation accuracy. The high-resolution GPS crustal movement velocity field obtainedby China crustal movement observation network(CMONOC-Ⅰ)and China continental tectonic environment monitoring network(CMONOC-Ⅱ), has clearly revealed the crustal tectonic movement and deformation of Qinghai-Tibet Plateau in the past 20 years. The research progress of current crustal movement and deformation characteristics of Qinghai-Tibet Plateau was systematically summarized based on GPS monitoring data, and the GPS data sources, and high-precision data processing methods and strategies for monitoring the crustal movement of Qinghai-Tibet Plateau were reviewed. The influence of different reference data on the processing results of GPS velocity field was discussed, and the current analysis models for crustal movement and deformation of Qinghai-Tibet Plateau were comprehensively explained from kinematics and dynamics. The current tectonic movement and deformation characteristics were deeply analyzed from both the shallow and deep of Qinghai-Tibet Plateau based on the calculations of integrated model. From the perspective of tectonic dynamic mechanism of plate movement, the current regional dynamics background of Qinghai-Tibet Plateau and the uplift mechanism of the mount Qomolangma region under its influence were interpreted in detail. Finally, the results of crustal movement and deformation of Qinghai-Tibet Plateau using GPS technology were summarized, and the important development trend of crustal deformation monitoring of Qinghai-Tibet Plateau in the future was also prospected. [ABSTRACT FROM AUTHOR]

BACKGROUND: Side-step cutting is the most common offensive technique in the field of sports that greatly increases the risk of knee injury. However, the biomechanical performance strategies and the characteristics of lower limb joint load during the side-step cutting are not very clear. OBJECTIVE: To carry out the biomechanics test of the side-step cutting in lower limb movement strategy among college female basketball and football players, and to analyze the kinematics and dynamics parameters of the lower limbs, providing an important reference for athletes and trainers to prevent lower limb injuries, especially cruciate ligament injury. METHODS: Twelve female football and basketball players coming from a university were selected as the experimental subjects. The kinematics and dynamics parameters of the side-step cutting were acquired synchronously by using the three-dimensional dynamometer and the motion image shooting system. The relevant data were processed and analyzed by SPSS 21.0 software. The study protocol was approved by Tianjin University of Sports in China. RESULTS AND CONCLUSION: (1) Football players had greater ankle metatarsal flexion angle and hip abduction angle, maximum ankle valgus angle, knee flexion and rotation angle with knee flexion and rotation angle changes. {2) Football players had greater peak ankle rotation and hip adduction moment, while basketball players had larger plantar flexion moment. (3} Basketball players have smaller first and second peak values of forward and backward partial braking force, the first peak value of vertical partial braking force and larger peak value of forward and backward partial pushing force. In the process of side-step cutting, football players are accustomed to stop in a sudden way with their forefeet touching, thus producing higher ground reaction force and increasing knee flexion angle to buffer, while having greater ankle valgus angle and knee rotation angle. Basketball players have smaller knee flexion angle in the process of side-step cutting. A smaller angle is not conducive to the lower limb joint to buffer the ground reaction force, and then increases the risk of anterior cruciate ligament injury. [ABSTRACT FROM AUTHOR]