Objective:To construct a structural equation model for neck work-related musculoskeletal disorders (WMSDs) in the footwear industry and analyze the mediating effect of fatigue in the model.Methods:From November 2018 to December 2019, stratified cluster sampling was adopted to select all the workers (3565 people) from 7 footwear enterprises in Fujian Province as the research subjects. The incidence of WMSDs, fatigue and work-related condition were investigated by using the Chinese version of the Musculoskeletal Disorders Questionnaire. A structural equation model of individual factors, work type, work posture, work organization factors, and fatigue on neck WMSDs was constructed to analyze the mediating effect of fatigue among them.Results:The incidence rate of WMSDs in the neck of footwear workers was 39.6% (1413/3565) , and the incidence rate of neck fatigue was 46.6% (1662/3565) .The final structural equation model was constructed with a χ2/ df of 9.927, a goodness-of-fit index of 0.961, an adjusted goodness-of-fit index of 0.946, and a root mean square error of approximation of 0.050. Except for the χ2/ df, all other fit indicators met the standard. Individual factors and work posture factors had a direct effect on neck WMSDs, with standardized path coefficients of 0.101 and 0.077, respectively ( P<0.05) . Individual factors, work type, work posture, and work organization had indirect effects on neck WMSDs through fatigue, the standardized path coefficients of indirect effects were 0.163, 0.090, 0.206, 0.105, respectively, and the standardized path coefficients of the total effect were 0.264, 0.090, 0.282, and 0.105 respectively ( P<0.05) . The indirect effects of individual factors and work posture factors on neck WMSDs through fatigue accounted for 61.74% and 73.05% of the total effects, respectively. The standardized path coefficient of fatigue on WMSDs was 0.689 ( P<0.001) , with the highest coefficient among all paths. Conclusion:Individual factors, work type, work posture, and work organization factors are important influencing factors in the occurrence and development of neck WMSDs in the footwear industry, and fatigue plays an important mediating role in them.

Objective:To investigate the occurrence of work-related musculoskeletal disorders (WMSDs) in bus drivers in Zhuhai City, analyze the ergonomic factors, and explore the prevention and control measures of WMSDs.Methods:From March to May 2023, 1675 active bus drivers from 5 branches of a bus group in Zhuhai were selected by stratified sampling method. The incidence of WMSDs among bus drivers in the past 12 months was investigated by using the modified Chinese Version of Musculoskeletal Disorders Questionnaire. The influencing factors of WMSDs were analyzed by χ2 test and generalized linear model. Results:The total incidence of WMSDs in bus drivers in the past 12 months was 47.2% (790/1675) , and the incidence of WMSDs in neck and shoulder and lower back was 36.9% (618/1675) and 31.7% (531/1675) , respectively. The χ2 test showed that there were statistically significant differences in the incidence of WMSDs among bus drivers with different individual factors such as body mass index (BMI) , physical exercise and looking down at mobile phones ( P<0.05) . There were significant differences in the incidence of WMSDs in the neck and shoulder of bus drivers with different years of service and number of stops on their routes ( P<0.05) . There were statistically significant differences in the incidence of WMSDs in the lower back of bus drivers with different one-way driving time, shift patterns, and rest breaks during work ( P<0.05) . Abnormal BMI, professional working years >12 years, uncomfortable working posture, frequent turning, slightly forward neck posture, large forward neck posture and long shoulder posture were the risk factors for WMSDs of bus drivers ( P<0.05) , and comfortable seat was the protective factor ( P<0.05) . One-way driving time >70 min, shift work schedules, uncomfortable working posture, slightly forward back posture, and frequent turning were the risk factors leading to lower back WMSDs ( P<0.05) , and physical exercise, comfortable driving cabin space, and seat comfort were the protective factors ( P<0.05) . Conclusion:The total incidence of WMSDs in bus drivers is higher, and ergonomic factors are related to the occurrence of WMSDs. In the implementation of bus driving space comfort, human-computer interaction interface friendliness and seat comfort, employers should be reasonable allocation of fitness facilities, regular training, reasonable shift organization and other measures to prevent and control the occurrence of bus drivers WMSDs.

Objective:To construct a structural equation model for neck work-related musculoskeletal disorders (WMSDs) in the footwear industry and analyze the mediating effect of fatigue in the model.Methods:From November 2018 to December 2019, stratified cluster sampling was adopted to select all the workers (3565 people) from 7 footwear enterprises in Fujian Province as the research subjects. The incidence of WMSDs, fatigue and work-related condition were investigated by using the Chinese version of the Musculoskeletal Disorders Questionnaire. A structural equation model of individual factors, work type, work posture, work organization factors, and fatigue on neck WMSDs was constructed to analyze the mediating effect of fatigue among them.Results:The incidence rate of WMSDs in the neck of footwear workers was 39.6% (1413/3565) , and the incidence rate of neck fatigue was 46.6% (1662/3565) .The final structural equation model was constructed with a χ2/ df of 9.927, a goodness-of-fit index of 0.961, an adjusted goodness-of-fit index of 0.946, and a root mean square error of approximation of 0.050. Except for the χ2/ df, all other fit indicators met the standard. Individual factors and work posture factors had a direct effect on neck WMSDs, with standardized path coefficients of 0.101 and 0.077, respectively ( P<0.05) . Individual factors, work type, work posture, and work organization had indirect effects on neck WMSDs through fatigue, the standardized path coefficients of indirect effects were 0.163, 0.090, 0.206, 0.105, respectively, and the standardized path coefficients of the total effect were 0.264, 0.090, 0.282, and 0.105 respectively ( P<0.05) . The indirect effects of individual factors and work posture factors on neck WMSDs through fatigue accounted for 61.74% and 73.05% of the total effects, respectively. The standardized path coefficient of fatigue on WMSDs was 0.689 ( P<0.001) , with the highest coefficient among all paths. Conclusion:Individual factors, work type, work posture, and work organization factors are important influencing factors in the occurrence and development of neck WMSDs in the footwear industry, and fatigue plays an important mediating role in them.

Objective To study the effect of medial collateral ligament(MCL)release on the squatting motion followling total knee arthroplasty(TKA)and provide reference data for ligament release during knee replacement surgery.Methods Based on CT and MRI images of a volunteer,a three-dimensional(3D)geometric anatomical model of the natural knee joint including bone tissues and major soft tissues was established.A finite element model of the artificial knee joint was established by simulating TKA surgery.The squatting motion after 30％release of the upper end,lower end,and both ends of the MCL was simulated,and motion characteristic data of the knee joint at flexion/extension angles from 0° to 135° were obtained.Results The effects of ligament release at different locations on knee squatting motion varied.After releasing the lower end,the medial translation,posterior translation,superior translation,and adduction of the femur relative to the tibia increased by 13.74％,3.83％,9.74％,and 2.37％,respectively,while the external rotation decreased by 36.8％.After releasing the upper end,the medial translation and posterior translation increased by 10.65％and 10％,respectively,while the superior translation,adduction,and external rotation decreased by 4.52％,33.89％,and 67.1％,respectively.After releasing both ends,the medial translation,posterior translation,and superior translation increased by 14.77％,9.39％,and 22.56％,respectively,while the adduction and external rotation decreased by 15.62％and 47.3％,respectively.Conclusions After MCL released,the medial translation,anterior translation,superior translation,and abduction of the femur relative to the tibia increased,while the external rotation decreased.Releasing the lower end had the least effect on these femoral movements,showing an obvious advantage.

Radiotherapy plays a pivotal role in the treatment of malignant tumors. The emergence of radiation resistance in malignant tumors, contributing to tumor recurrence, progression, or distant metastasis, remains a significant treatment challenge. Exploring the mechanisms underlying radiation resistance and overcoming the radio-resistance of tumors have become urgent problems in oncological practice. Cuproptosis, a copper-dependent form of regulated cell death, is driven by the aggregation of lipoylated proteins and the reduction of Fe-S cluster proteins, etc. Copper and cuproptosis are not only intricately related to the incidence and development of tumors, but also participate in radiation resistance of tumor cells. Strategic interventions targeting copper and inducing cuproptosis will present promising avenues for overcoming radiation resistance and further improving the prognosis of tumor patients. This review comprehensively delineates established and potential mechanisms governing the intricate crosstalk between radiation resistance and cuproptosis, aiming to provide reference for overcoming radiation resistance in malignant tumor cells.

Objective To study the effect of medial collateral ligament(MCL)release on the squatting motion followling total knee arthroplasty(TKA)and provide reference data for ligament release during knee replacement surgery.Methods Based on CT and MRI images of a volunteer,a three-dimensional(3D)geometric anatomical model of the natural knee joint including bone tissues and major soft tissues was established.A finite element model of the artificial knee joint was established by simulating TKA surgery.The squatting motion after 30％release of the upper end,lower end,and both ends of the MCL was simulated,and motion characteristic data of the knee joint at flexion/extension angles from 0° to 135° were obtained.Results The effects of ligament release at different locations on knee squatting motion varied.After releasing the lower end,the medial translation,posterior translation,superior translation,and adduction of the femur relative to the tibia increased by 13.74％,3.83％,9.74％,and 2.37％,respectively,while the external rotation decreased by 36.8％.After releasing the upper end,the medial translation and posterior translation increased by 10.65％and 10％,respectively,while the superior translation,adduction,and external rotation decreased by 4.52％,33.89％,and 67.1％,respectively.After releasing both ends,the medial translation,posterior translation,and superior translation increased by 14.77％,9.39％,and 22.56％,respectively,while the adduction and external rotation decreased by 15.62％and 47.3％,respectively.Conclusions After MCL released,the medial translation,anterior translation,superior translation,and abduction of the femur relative to the tibia increased,while the external rotation decreased.Releasing the lower end had the least effect on these femoral movements,showing an obvious advantage.

Objective:To investigate the occurrence of work-related musculoskeletal disorders (WMSDs) in bus drivers in Zhuhai City, analyze the ergonomic factors, and explore the prevention and control measures of WMSDs.Methods:From March to May 2023, 1675 active bus drivers from 5 branches of a bus group in Zhuhai were selected by stratified sampling method. The incidence of WMSDs among bus drivers in the past 12 months was investigated by using the modified Chinese Version of Musculoskeletal Disorders Questionnaire. The influencing factors of WMSDs were analyzed by χ2 test and generalized linear model. Results:The total incidence of WMSDs in bus drivers in the past 12 months was 47.2% (790/1675) , and the incidence of WMSDs in neck and shoulder and lower back was 36.9% (618/1675) and 31.7% (531/1675) , respectively. The χ2 test showed that there were statistically significant differences in the incidence of WMSDs among bus drivers with different individual factors such as body mass index (BMI) , physical exercise and looking down at mobile phones ( P<0.05) . There were significant differences in the incidence of WMSDs in the neck and shoulder of bus drivers with different years of service and number of stops on their routes ( P<0.05) . There were statistically significant differences in the incidence of WMSDs in the lower back of bus drivers with different one-way driving time, shift patterns, and rest breaks during work ( P<0.05) . Abnormal BMI, professional working years >12 years, uncomfortable working posture, frequent turning, slightly forward neck posture, large forward neck posture and long shoulder posture were the risk factors for WMSDs of bus drivers ( P<0.05) , and comfortable seat was the protective factor ( P<0.05) . One-way driving time >70 min, shift work schedules, uncomfortable working posture, slightly forward back posture, and frequent turning were the risk factors leading to lower back WMSDs ( P<0.05) , and physical exercise, comfortable driving cabin space, and seat comfort were the protective factors ( P<0.05) . Conclusion:The total incidence of WMSDs in bus drivers is higher, and ergonomic factors are related to the occurrence of WMSDs. In the implementation of bus driving space comfort, human-computer interaction interface friendliness and seat comfort, employers should be reasonable allocation of fitness facilities, regular training, reasonable shift organization and other measures to prevent and control the occurrence of bus drivers WMSDs.

Ergonomic Principle for the Prevention of Work-Related Musculoskeletal Disorders Part 1: General Principles (T/WSJD 14.1-2020) is the first guideline standard for the prevention of work-related musculoskeletal disorders provided to employers and occupational health technical service institutions in China, which covers ergonomic risk factors and their hazard definition, ergonomic prevention principles, risk assessment process, risk control process and risk evaluation principles. The standard specifically clarify the specific types of adverse ergonomic risk factors and control strategies and the standard process of systematic ergonomic risk assessment, providing implementation paths and practical guidance for eliminating/reducing adverse ergonomic risks and enhance workplace environments to prevent work-related musculoskeletal disorders. This paper interprets and analyzes the background of standard establishment, formulation process, fundamental basis, and main content, etc., to provide scientific and accurate technical support for enterprise managers, labours and technical personnel of occupational health institutions to optimize the use of this standard.

Objective:To evaluate the improvement effect of ergonomics in the assembly position of an automotive parts production company.Methods:From February to December 2023, the assembly positions and 8 operators of an automobile brake parts production company were selected as the research objects. The Swedish Ergonomic Hazard Identification Method and rapid upper limb assessment (RULA) were used to identify and evaluate the adverse ergonomic factors of work-related musculoskeletal disorders (WMSDs) in different parts of the body before and after the improvement. Through field investigation, observation and personnel interviews, three ergonomic problems were identified that need to be solved, namely, the height of the assembly table did not match the height of the operator, the storage space for small accessories was not set reasonably, and empty boxes were difficult to be placed. Technical improvements were made by designing an adjustable height assembly table, improving the layout of the workbench, and designing a mechanical pedal automation device. Statistical analysis was performed by t-test and paired rank sum test to evaluate the effectiveness of ergonomic improvements. Results:The operation of the assembly position could be divided into 13 actions, and the time to complete 1 cycle was (83.0±2.7) s. The Swedish Ergonomic Hazard Identification Method identified 28 adverse ergonomic factors of WMSDs in different parts before improvement, and 15 adverse ergonomic factors after improvement. Before ergonomics improvement, the RULA scores were 5 to 7 points, and the risk levels of 6 workers were Ⅳ (very high risk) and 2 workers were Ⅲ (moderate risk). After ergonomics improvement, the RULA score was 4 points, and the risk level was reduced to Ⅱ (low risk). Paired rank sum test results showed that there were statistically significant differences in upper arm, A-part (upper arm, lower arm and wrist) exertion and load, A-part muscle use, neck, total score, and risk level before and after improvement ( P<0.05). Per capita productivity of assembly post was (40.1±1.4) pieces/ (person·hour) before the improvement and (44.0±1.7) pieces/ (person·hour) after the improvement, the difference was statistically significant ( t=50.35, P<0.001) . Conclusion:The ergonomic improvement measures can reduce the adverse ergonomic factors in the assembly position of an automotive parts production company, reduce the risk of WMSDs, and improve the production efficiency.

Objective:To investigate the incidence of shoulder work-related musculoskeletal disorders (WMSDs) among occupational population in China, and to explore their intrinsic association with personal and work-related factors.Methods:In April 2024, 73497 valid questionnaires of the Chinese version of the Musculoskeletal Disorders Electronic Questionnaire were retrospectively analyzed from June 2018 to December 2023 in 22 provinces and 29 key industries in China, and the general information, occurrence of WMSDs and related risk factors of key occupational populations in different regions in China were collected. By using Chi-square test and confirmatory factor analysis, the relationship between shoulder fatigue and pain in key occupational groups and individual factors, work type, work posture and work organization was discussed, and the internal relationship was analyzed based on structural equation model.Results:Higher incidence of shoulder fatigue and pain were associated with female, lack of physical exercise, uncomfortable working posture and neck leaning forward ( P<0.05). Structural equation model analysis showed that work type, work posture and work organization were strongly correlated ( r=0.58, 0.55). Work organization and work type were strongly correlated with shoulder fatigue ( r=0.65) and moderately correlated with shoulder fatigue ( r=0.21). Shoulder fatigue was moderately associated with shoulder pain ( r=0.40). Individual factors, work type, work posture and shoulder fatigue could directly affect shoulder pain ( OR=0.07, -0.09, 0.17 and 0.40), and work type and work posture could also indirectly affect shoulder pain through shoulder fatigue ( OR=0.08, 0.03). Work organization only indirectly affected shoulder pain through shoulder fatigue ( OR=0.26) . Conclusion:The main influencing factor of shoulder pain is shoulder fatigue, followed by work posture and individual factors. Structural equation model can better reflect the complex relationship between work type, work posture and work organization and shoulder WMSDs. Improving work posture and work organization may be an effective way to control the influence of shoulder fatigue on shoulder pain.