1.Three-dimensional finite element simulation and biomechanical analysis of human mandible injury
Tao LEI ; Wenbin TU ; Tingting WANG ; Jiajun ZHENG ; Liangxian XIE
Chongqing Medicine 2016;(2):151-155
Objective The simulation of the human mandible injury was carried out by using the finite element simulation technology ,and the biomechanical analysis of simulation results was developed to explore the mechanism of injuries .Methods The Chinese Visible Human digital data were used to establish the three-dimensional element model of mandible injuries ,and the dynam-ic processes of human mandible injuries in different conditions were simulated ,and the biomechanical analysis were carried out by u-sing the Von Mises stress and effective strain .Results The three-dimensional element model of mandible injuries was established , the dynamic damage and fracture of human mandible were simulated successfully ,the mandibular angle and condylar were the predi-lection parts of high-stress ,high-strain and fractures .Conclusion The Von Mises stress and effective strain can be used to predict and judge the bone tissue injuries ,the finite element method can simulate the impact injuries of mandible effectively ,and the simula-ted results can provide guidance and reference for basic research and clinical treatment of oral and maxillofacial injuries .
2.Follow-up observation of carotid artery stent implantation by color Doppler ultrasound combined with TCD
Xuhui DAI ; Xiaomei YU ; Manli SU ; Fang MEI ; Yuanfeng LIU ; Siwen CHEN ; Hongli ZHOU ; Jiajun TU
Chinese Medical Equipment Journal 2017;38(2):86-88
Objective To apply color Doppler flow imaging (CDFI) and transcranial Doppler (TCD) to the follow-up observation of the changes of cervical vessel,intracranial hemodynamics and cerebrovascular reserve capacity (CVR) of the patients after carotid artery stent implantation.Methods Totally 96 patients with carotid artery stent implantation underwent CDFI and TCD examinations,and the changes of hemodynamics were compared before and 1 month,6 months,1 a and 2 a after implantation.Results The values of peak systolic velocity (PSV) and resistance index (RI) at the areas of carotid stenosis were lower significantly than those before implantation,while the values of PSV,pulsatility index (PI) and CVR of the middle cerebral artery were obviously higher than those before implantation (P<0.05).There were no significant differences between the cervical and intracranial hemodynamics indexes 1 month,6 months,1 a and 2 a after treatment.Two-year follow-up found 4 cases of restenoses after implantation,and the rate for restenosis was 4.2%.Conclusion Carotid artery stent implantation improves significantly cervical and intracranial blood supply as well as CVR of the carotid stenosis patient,and CDFI combined with TCD can be used for the accurate evaluation of the efficacy and postoperative follow-up of carotid artery stent implantation.
3.Application and implications of European Union's aging policies in occupational health
Zhenzhen YU ; Jiajun TU ; Guodong LU
Journal of Environmental and Occupational Medicine 2024;41(9):977-981
China has entered a stage of deep aging. The expanding aging population and subsequently an aging labor force pose significant challenges to China’s social and economic development. European Union (EU) countries have entered the aging phase earlier and to a greater extent. To address the labor shortage and the rising dependency ratio, the EU has implemented a series of policies and measures, including raising retirement age, promoting flexible retirement, enhancing work flexibility, improving welfare for elderly workers, creating age-friendly environments, focusing on occupational health, strengthening knowledge and skills training, and leveraging digital technologies in the workplace. These measures aim to prevent premature exit of elderly workers, better balance their work and life needs, improve occupational health and skills, and enhance overall work efficiency of companies. This review discussed the experience and lessons learned from the EU countries in addressing the aging workforce from the perspectives of occupational health and occupational skills development, aiming to provide rational suggestions to assist China in better adapting the challenges of aging workforce after steadily and orderly advancing the gradual reform of the statutory retirement age, thereby improving the efficiency of the overall workforce and the stability of the labor market, driving the talent dividend of highly educated and skilled middle-aged and elderly employees, and ultimately promoting sustained economic and social development.