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 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 learn the production efficient of platelet components among prefecture-level blood stations in China, to provide supporting data for those blood stations to optimize the production mode of platelet components and continuously improve production efficiency and supply capacity. 【Methods】 The data from 2017 to 2020 was obtained from 24 prefecture-level blood stations who were the members of the practice comparison network for blood institutes in China. The collection units of apheresis platelets, the number of dual-collections of apheresis platelets and plasma, the average apheresis units of one platelet apheresis procedure, the discarded rate of apheresis platelets, the amount of expired apheresis platelets and the amount of apheresis platelets issued were collected. For concentrated platelets, the prepared amount of platelet concentrates and the amount of expired platelet concentrates were collected; both the quantity of qualified and issued concentrated platelets were submitted for statistical analysis.The total output and efficiency of platelet components were calculated based on the collected data. 【Results】 The average annual growth rate of apheresis platelets collection in 24 prefecture-level blood stations was 12.23%, accounting for 99.80% of the total platelet output; the average collection unit of one platelets apheresis procedure was 1.75; from 2019 to 2020, only 5 blood stations performed dual-collection of platelet and plasma during one apheresis procedure; the discarded rate of apheresis platelets was 0.28%, of which 0.007% was due to expiration. A total of 1 621.2 therapeutic units of concentrated platelets were prepared, and 13.03% of them was discarded due to the expiration. The production efficiency of platelet components was 97.56%, of which the production efficiency of apheresis platelets was 97.61% and the production efficiency of concentrated platelets was 74.43%. 【Conclusion】 There are large regional differences in the supply capacity of platelet components in prefecture-level blood stations. Apheresis platelets are the main resource of platelet components product, and the collection capacity is increasing over the years with the characteristics of high production efficiency and low expiration scrapping rate. However, the preparation of concentrated platelets are still limited with relatively low production and high expiration discarded rate.

PurposeTo study the effect of gasoline on the extracellular matrix of dermis in rat. Methods45 male Wistar rats were divided into control group, 3 different exposure level groups, which were exposed to gasoline on 2 cm× 3 cm skin area with the dose of 250 mg/cm2 for 1 (group A) ,4(group B)and 8 days (group C) respectively,and an intervention group exposed to 250 mg/cm2 × 8 days gasoline after the application of protective agent on skin. After the treatment, collagen, elastin and glycosaminoglycan (GAG) were assayed in skin departed from intoxicated area.ResultsCompared with control group, collagen was decreased in group C(P<0.05); elastin was decreased in group B and C (P<0.05); glycosaminoglycan was decreased in all exposure groups and intervention group ( P < 0.05 or P < 0.01 )。 Collagen, elastin and glycosaminoglycan(GAG) were significantly lower in group C than in intervention group ( P < 0.05 ). ConclusionsThe extracellular matrix of dermis,including collagen,elastin and GAG were decreased in rat dermal exposed to gasoline.