Objective To investigate the effect of monitor unit(MU)optimization on volumetric modulated arc therapy(VMAT)for nasopharyngeal carcinoma(NPC).Methods Totally 21 NPC patients confirmed pathologically at some hospital from October 2022 to March 2023 were selected retrospectively,and for each patient a double-arc VMAT plan named base was designed without using the monitor unit objective(MUO)tool and optimized by the photon optimization algorithm.With the parameter kept constant,Plan base was reoptimized with only the MUO tool by regulating its Maximum MU to 30％of the total MU of Plan base and setting Strength values as 50,80 and 100 respectively to obtain Plan S50,S80 and S100.Plan base was compared with Plan S50,S80 and S100 in terms of dose distributions of the target volumes and organs at risk(OARs),MU,beam-on time and γ pass rate.SPSS 17.0 software was used for statistical analysis.Results In Plan S100 only 4 patients had a decrease of more than 4％in theD98％to the PCTV2 target volume compared with that in Plan base.In Plan S80 only 2 patients had a decrease of between 3％and 4％in the Dmax to PGTV and PGTVnd and D98％to PCTV2 when compared with those in Plan base,and most of the dosimetric parameters to the other target volumes had the changing amplitudes lower than 2％.When compared with Plan base,Plan S50,S80 and S100 all increased theDmaxto the brainstem significantly(all P＜0.05),with the maximum increment not exceeding 1.5％.In Plan S50 the D502％and Dmean to the right and left parotid glands were lowered,and in Plan S80 there were decreases found in the Dmean to the right and left parotid glands andD50％to the left parotid gland,with statistically significant differences(P＜0.001),and in Plan S100 the D50％and Dmean to the right and left parotid glands and the Dmax to the spinal cord increased significantly when compared with those in Plan base(all P＜0.05).In Plan S80 and S100 the V40 of the thyroid relatively rose statistically when compared with that in Plan base(P＜0.05).In Plan S50,S80 and S100 the MU was decreased by 5.1％,21.5％and 30.9％respectively when compared with that in Plan base,and the average beam-on time of all the four plans was kept within 2.5 min.γ pass rates increased sequentially for Plan base,S50,S80 and S100 under 1％/1 mm conditions.Conclusion In NPC VMAT MU optimization effectively decreases the planned MU and improves γ pass rates under 1％/1 mm conditions while ensuring the dose to the target volume and OAR protection.[Chinese Medical Equipment Journal,2025,46(2):56-62]

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.

Objective:To explore the structural equation model to explore the levels of work-related musculoskeletal disorders (WMSDs) and various risk factors in the feet and ankle of China's occupational population, providing scientific basis for for preventing WMSDs in feet and ankles.Methods:Data of 73497 national occupational epidemiological cases were selected from June 2018 to December 2023 used the Chinese version of the Electronic Questionnaire on Musculoskeletal Disorders. The adverse ergonomic factors and their source classification standard and confirmatory factor analysis were used to investigate foot and ankle WMSDs and their related risk factors (including individual factors, work organization, work posture, work type, fatigue, etc.) in key occupational groups in China, and structural equation model hypothesis, fitting, verification, and path and intermediary effect analysis were carried out. The model fit evaluation indexes included Chi-square specific degrees of freedom ( χ2/ df), gauge fit index (NFI), Tucker Lewis index (TLI), goodness of Fit index (GFI), adjusted Goodness of Fit index (AGFI) and approximate root mean square error (RMSEA) . Results:A total of 73497 occupational workers were surveyed, with local muscle fatigue and WMSDs incidence rates in the feet and ankles being 17.17% and 12.06%, respectively. The fitting index of the adjusted structural equation model basically meets the standard (GFI=1, AGFI=1, RMESA=0.042, NFI=0.716, TLI=0.663). The top three factors affecting feet and ankle WMSDs are feet and ankle muscle fatigue, work type, and work organization, with standardized path coefficients of 0.221, 0.105, and 0.095, respectively. The top two factors affecting feet and ankle muscle fatigue are work organization and work type, with standardized path coefficients of 0.548 and 0.383, respectively. Feet and ankle muscle fatigue, work type, work organization, and work posture have a direct effect on feet and ankle WMSDs, with effect values of 0.221, 0.105, 0.095, and 0.077, respectively. The organization and type of work can also have indirect effects through feet and ankle muscle fatigue, with effect values of 0.121 and 0.084, respectively.Conclusion:Feet and ankle muscle fatigue has a direct impact on WMSDs, and plays a mediating role between ankle and ankle WMSDs caused by work organization and work type. Feet and ankle muscle fatigue is an important pathway leading to feet and ankle WMSDs. It is recommended that employers and managers detect job fatigue early and take corresponding prevention and intervention measures, which can play a key role in preventing feet and ankle WMSDs.

Objective:To explore the structural relationship between WMSDs in the upper limbs and various risk factors in the occupational population in China, based on a large sample epidemiological survey and structural equation analysis, and to establish a structural equation model, so as to lay a foundation for the prevention and control of such diseases.Methods:The Chinese version of the Musculoskeletal Disorders Electronic Questionnaire was used to conduct a nationwide survey on the prevalence of WMSDs in the upper extremity. Six factors related to WMSDs in the upper extremity were extracted by the classification standard of adverse ergonomic factors and their source and confirmatory factor analysis, including work organization, work type, upper extremity work posture, individual factors, upper extremity fatigue and upper extremity WMSDs. The structural equation analysis was carried out and the structural equation model was established.Results:The incidence of WMSDs and fatigue in the upper limbs was 24.44% and 43.76%, respectively. The adjusted structural equation model fitting indicators were generally up to the standard (GFI=1.000, AGFI=1.000, RMSEA=0.043, NFI=0.808, TLI=0.784) . The four exogenous latent variables of work organization, work type, upper limb work posture and individual factors were correlated. There was a strong positive correlation between job type and upper limb work posture ( r=0.865) , a moderate positive correlation between work organization and job type and upper limb work posture ( r=0.570, 0.490) , and a weak negative correlation between individual factors and the other three exogenous latent variables. Upper limb work posture and individual factors had direct effects on upper limb WMSDs, and the effect coefficients were 0.10 and 0.06, respectively. Upper limb fatigue played a mediating role between work organization, work type, upper limb work posture and upper limb WMSDs. The effect coefficient was 0.46, and the composition ratios of indirect effects were 100.0%, 100.0%, and 38.3%, respectively. The direct path effect of upper limb work posture, individual factors and upper limb WMSDs was weaker than the mediating path through upper limb fatigue. Conclusion:When carrying out the prevention and control of upper limbWMSDs, it is necessary to comprehensively consider the pathogenesis path of upper limb muscle fatigue and upper limb WMSDs caused by work organization, work type, and upper limb work posture, so as to provide theoretical reference for improving the prevention and control level of such diseases.

Objective To investigate the effect of monitor unit(MU)optimization on volumetric modulated arc therapy(VMAT)for nasopharyngeal carcinoma(NPC).Methods Totally 21 NPC patients confirmed pathologically at some hospital from October 2022 to March 2023 were selected retrospectively,and for each patient a double-arc VMAT plan named base was designed without using the monitor unit objective(MUO)tool and optimized by the photon optimization algorithm.With the parameter kept constant,Plan base was reoptimized with only the MUO tool by regulating its Maximum MU to 30％of the total MU of Plan base and setting Strength values as 50,80 and 100 respectively to obtain Plan S50,S80 and S100.Plan base was compared with Plan S50,S80 and S100 in terms of dose distributions of the target volumes and organs at risk(OARs),MU,beam-on time and γ pass rate.SPSS 17.0 software was used for statistical analysis.Results In Plan S100 only 4 patients had a decrease of more than 4％in theD98％to the PCTV2 target volume compared with that in Plan base.In Plan S80 only 2 patients had a decrease of between 3％and 4％in the Dmax to PGTV and PGTVnd and D98％to PCTV2 when compared with those in Plan base,and most of the dosimetric parameters to the other target volumes had the changing amplitudes lower than 2％.When compared with Plan base,Plan S50,S80 and S100 all increased theDmaxto the brainstem significantly(all P＜0.05),with the maximum increment not exceeding 1.5％.In Plan S50 the D502％and Dmean to the right and left parotid glands were lowered,and in Plan S80 there were decreases found in the Dmean to the right and left parotid glands andD50％to the left parotid gland,with statistically significant differences(P＜0.001),and in Plan S100 the D50％and Dmean to the right and left parotid glands and the Dmax to the spinal cord increased significantly when compared with those in Plan base(all P＜0.05).In Plan S80 and S100 the V40 of the thyroid relatively rose statistically when compared with that in Plan base(P＜0.05).In Plan S50,S80 and S100 the MU was decreased by 5.1％,21.5％and 30.9％respectively when compared with that in Plan base,and the average beam-on time of all the four plans was kept within 2.5 min.γ pass rates increased sequentially for Plan base,S50,S80 and S100 under 1％/1 mm conditions.Conclusion In NPC VMAT MU optimization effectively decreases the planned MU and improves γ pass rates under 1％/1 mm conditions while ensuring the dose to the target volume and OAR protection.[Chinese Medical Equipment Journal,2025,46(2):56-62]

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.

Objective:To explore the structural equation model to explore the levels of work-related musculoskeletal disorders (WMSDs) and various risk factors in the feet and ankle of China's occupational population, providing scientific basis for for preventing WMSDs in feet and ankles.Methods:Data of 73497 national occupational epidemiological cases were selected from June 2018 to December 2023 used the Chinese version of the Electronic Questionnaire on Musculoskeletal Disorders. The adverse ergonomic factors and their source classification standard and confirmatory factor analysis were used to investigate foot and ankle WMSDs and their related risk factors (including individual factors, work organization, work posture, work type, fatigue, etc.) in key occupational groups in China, and structural equation model hypothesis, fitting, verification, and path and intermediary effect analysis were carried out. The model fit evaluation indexes included Chi-square specific degrees of freedom ( χ2/ df), gauge fit index (NFI), Tucker Lewis index (TLI), goodness of Fit index (GFI), adjusted Goodness of Fit index (AGFI) and approximate root mean square error (RMSEA) . Results:A total of 73497 occupational workers were surveyed, with local muscle fatigue and WMSDs incidence rates in the feet and ankles being 17.17% and 12.06%, respectively. The fitting index of the adjusted structural equation model basically meets the standard (GFI=1, AGFI=1, RMESA=0.042, NFI=0.716, TLI=0.663). The top three factors affecting feet and ankle WMSDs are feet and ankle muscle fatigue, work type, and work organization, with standardized path coefficients of 0.221, 0.105, and 0.095, respectively. The top two factors affecting feet and ankle muscle fatigue are work organization and work type, with standardized path coefficients of 0.548 and 0.383, respectively. Feet and ankle muscle fatigue, work type, work organization, and work posture have a direct effect on feet and ankle WMSDs, with effect values of 0.221, 0.105, 0.095, and 0.077, respectively. The organization and type of work can also have indirect effects through feet and ankle muscle fatigue, with effect values of 0.121 and 0.084, respectively.Conclusion:Feet and ankle muscle fatigue has a direct impact on WMSDs, and plays a mediating role between ankle and ankle WMSDs caused by work organization and work type. Feet and ankle muscle fatigue is an important pathway leading to feet and ankle WMSDs. It is recommended that employers and managers detect job fatigue early and take corresponding prevention and intervention measures, which can play a key role in preventing feet and ankle WMSDs.

Objective:To explore the structural relationship between WMSDs in the upper limbs and various risk factors in the occupational population in China, based on a large sample epidemiological survey and structural equation analysis, and to establish a structural equation model, so as to lay a foundation for the prevention and control of such diseases.Methods:The Chinese version of the Musculoskeletal Disorders Electronic Questionnaire was used to conduct a nationwide survey on the prevalence of WMSDs in the upper extremity. Six factors related to WMSDs in the upper extremity were extracted by the classification standard of adverse ergonomic factors and their source and confirmatory factor analysis, including work organization, work type, upper extremity work posture, individual factors, upper extremity fatigue and upper extremity WMSDs. The structural equation analysis was carried out and the structural equation model was established.Results:The incidence of WMSDs and fatigue in the upper limbs was 24.44% and 43.76%, respectively. The adjusted structural equation model fitting indicators were generally up to the standard (GFI=1.000, AGFI=1.000, RMSEA=0.043, NFI=0.808, TLI=0.784) . The four exogenous latent variables of work organization, work type, upper limb work posture and individual factors were correlated. There was a strong positive correlation between job type and upper limb work posture ( r=0.865) , a moderate positive correlation between work organization and job type and upper limb work posture ( r=0.570, 0.490) , and a weak negative correlation between individual factors and the other three exogenous latent variables. Upper limb work posture and individual factors had direct effects on upper limb WMSDs, and the effect coefficients were 0.10 and 0.06, respectively. Upper limb fatigue played a mediating role between work organization, work type, upper limb work posture and upper limb WMSDs. The effect coefficient was 0.46, and the composition ratios of indirect effects were 100.0%, 100.0%, and 38.3%, respectively. The direct path effect of upper limb work posture, individual factors and upper limb WMSDs was weaker than the mediating path through upper limb fatigue. Conclusion:When carrying out the prevention and control of upper limbWMSDs, it is necessary to comprehensively consider the pathogenesis path of upper limb muscle fatigue and upper limb WMSDs caused by work organization, work type, and upper limb work posture, so as to provide theoretical reference for improving the prevention and control level of such diseases.

The excipient processing is an essential part of traditional Chinese medicine processing, and understanding its scientific connotations is a critical scientific issue that urgently needs resolution. Building upon a foundation where the composition of traditional Chinese medicine substances is fundamentally clear, this paper applies the techniques and methods of chemoinformatics to the study of the excipient processing mechanism. Relevant information on traditional Chinese medicines processed with four kinds of excipients (wine, vinegar, salt and honey) was collected, including properties, taste, meridian tropism, chemical components, etc. Molecular descritors and skeletons corresponding to each chemical component were calculated using chemoinformatics to characterize the properties and structural features of the components. Characteristic components associated with the four excipients (wine, vinegar, salt and honey) were explored through multivariate statistical analysis and Murcko skeleton analysis. Further analysis, taking honey-processed Astragali Radix as an example, the focus was on the impact of the processing excipient honey on the solubility and permeability of its characteristic pharmacologically active components (isoflavones). It was discovered that the excipient honey can increase their solubility and permeability, emphasizing that the impact of processing excipients on the pharmacological classification properties is a key breakthrough in elucidating the mechanism of excipient processing. In summary, this study analyzed the characteristic components associated with the processing excipients "wine, vinegar, salt and honey" based on their composition characteristics, providing data support for the research on the mechanism of excipient processing from a biopharmaceutical perspective.

The breakage pattern of unit particles during the production of oral solid dosage forms (OSD) is closely related to the quality of intermediate or final products. To accurately characterize the particles and study the evolution law of particle breakage, the Bonding model of the discrete element method (DEM) was used to investigate the breakage patterns of model parameters, particle shape and process conditions (loading mode and loading rate) on the dynamic breakage, force-time curve, breakage rate, maximum breakage size ratio and fracture strength of particles. The results showed that the particle breakage force was positively correlated with normal strength and bonded disk scale, negatively correlated with normal stiffness per unit area and tangential stiffness per unit area, and weakly correlated with tangential strength. The particle breakage rate was negatively correlated with the aspect ratio of the particles, and the maximum breakage size ratio was positively correlated with the aspect ratio of the particles; among the three loading modes, the breakage rate of compression breakage model was the largest, the breakage rate of shear breakage model was the second largest, and the breakage rate of wear breakage model was the smallest; the maximum breakage size ratio was positively correlated with the loading rate, the loading mode and the loading rate had no mutual influence on particle breakage rate, but had mutual influence on the maximum breakage size ratio. The research results will provide a theoretical basis for the shift of OSD from batch manufacturing to advanced manufacturing.