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Abstract@#To help children and adolescents grow up healthily, using literature, comparative analysis and other research methods, the historical development of Japan s physical fitness assessment system for children and adolescents are analyzed for the content structure of the latest version of its physical fitness assessment system (Sports adaptability assessment Ⅱ). On the basis of this analysis, some practical suggestions are proposed for improving the National Physical Fitness Standards for Students in China, such as adding a physical fitness assessment system for preschoolers, grouping the test subjects by age and setting common test indicators for males and females. Thus, the improved National Student Physical Fitness Standard is more aligned with the physical and mental growth patterns of Chinese children and adolescents.
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Abstract@#Speed is an important component of physical fitness testing for students around the world. On the whole, the different testing systems usually set up various indexes based on the moving speed, action speed and reaction speed; the indexes are diverse but uniform in number; there are differences in the age of application of the indexes and no gender differences. As far as the classification of indexes is concerned, there are two types of movement:sprinting and shuttle run, for the moving speed test indexes; there are differences in the need for action speed and reaction speed tests. Based on this, from the perspective of energy metabolism and health benefits, the properties and testing methods for measuring moving speed and the need for action speed and reaction speed testing are analyzed. The study shows that acceleration capability should be a measured attribute of moving speed，the 30 m running can be used as a general index of moving speed for all students; the shuttle run is not suitable as an index of moving speed; action speed is less correlated with physical health, so it should not be included in the testing system for the time being; and reaction speed which closely relates to physical health,should be included in the testing system.
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BACKGROUND: At present, related finite element models have been used to simulate the femoral fracture, and the effects of loading rate, loading angle and cancellous bone on the fracture of hip have been discussed. However, the fracture simulation of trabecula is still lack of relevant research. OBJECTIVE: To simulate the biomechanical process of osteoporotic trabecular compression fracture in ovariectomized rats. METHODS: The right femur of ovariectomized rats was scanned at the distal end of femur by Micro-CT. The microstructure parameters and three-dimensional model of the region of interest of the rat femur were obtained. After geometric optimization in Geomagic Studio, they were pretreated in HyperMesh 14.0, including volume mesh division, setting material property parameters, boundary conditions, setting load of 1 200 N, acting time of 2 ms, and they were calculated in LS-DYNA software. RESULTS AND CONCLUSION: (1) The bone trabeculae in the region of interest showed uneven spatial distribution. (2) The bone trabeculae with small volume and small number first presented deformation fracture, and the plate shape and bone trabeculae with large volume finally demonstrated fracture collapse. (3) The change trend of von Mises stress was roughly the same as that of bone trabeculae fracture collapse. The fracture collapse process of bone trabeculae in the region of interest included vertical collapse and horizontal torsion, in which the degree and rate of horizontal torsion were lower than that of vertical collapse, making the size and rate of cross-section torsion angle less than that of coronal plane angle. (5) The increase and peak value of shear stress of failure unit were smaller than Von-mises stress. (6) These results indicate that fracture collapse of bone trabecula is a complex process, including deformation and angle of different planes.
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OBJECTIVE： To investigate the mechanism of Drynariae rhizoma in the treatment of osteoporosis （OP）. METHODS： The active compounds and targets of D. rhizoma were obtained by using Bioinformatics Analysis Tool for Molecular Mechanism of Traditional Chinese Medicine （BATMAN-TCM database）. The targets of relevant compounds were also obtained by GeneCards database， and targets of D. rhizoma were obtained by the combination of the two. The disease targets corresponding to OP were obtained by using TTD， DrugBank， OMIM， GAD， PharmGKB and CTD database. The D. rhizoma-OP disease intersection targets were obtained after intersecting with the target of D. rhizoma. PPI network was constructed by STRING online database， analyzed by using Cytoscape 3.6.1 software to obtain key targets and showed by network visualization. Gene ontology（GO） analysis of drug-disease intersection target were conducted by DAVID online tools. KEGG pathway enrichment analysis was conducted by KOBAS online tools to screen the significant enrichment pathway （P＜0.05）. The key genes were screened by MCC algorithm. RESULTS： There were 7 active compounds of D. rhizoma 136 intersection targets of D. rhizoma-OP disease. GO analysis results showed that the biological function of intersection target mainly included chemical reaction， steroid metabolic process as well as cellular response to chemical stimulus and so on； cell composition mainly included extracellular space， extracellular area and cytoplasm；molecular functions included heme binding， tetrapyrrole binding and monooxygenase activity， etc. KEGG pathway enrichment showed that above targets were mainly related to bone metabolism， endocrinology， inflammation， tumor， apoptosis， etc. Thirty key genes （such as ALB， AKT1， JUN， etc.， P≤1.96×10－9） were screened by MCC algorithm. CONCLUSIONS： The mechanism of action of D. rhizoma in the treatment of OP is in multi-target and multi-system manner. In addition to influencing the related pathways of bone metabolism， it can also affect various metabolic pathways in vivo.