Background Fatigue among distribution network live-line workers in complex operational environments has become increasingly severe and requires widespread attention. Objective To investigate the positive rates of fatigue and associated influencing factors of live-line power distribution workers, and to make a reasonable strategy to reduce the fatigue of front-line workers. Methods Power supply companies in Guangdong, Guangxi, and Yunnan provinces were selected by cluster sampling in 2023, and all front-line live-line workers in the selected companies were recruited. The questionnaire used in this study consisted of two parts: one was the Fatigue Scale-14 (FS-14) for investigating fatigue status and the other was for associated influencing factors. A FS-14 score greater than 3 points was defined as fatigue. \begin{document}$ {\chi }^{2} $\end{document} test and logistic regression were employed to analyze the factors affecting fatigue. Results A total of 1341 questionnaires were distributed, and 1217 valid questionnaires were recovered, with a valid response rate of 90.75%. The average fatigue score of the participants was (6.84±3.79) points, and a total of 1054 participants scored over 3, resulting a fatigue positive rate of 86.6%. The logistic regression model showed that working under extreme weather (OR=2.03, 95%CI: 1.38, 2.98), overtime 2-3 times a week (OR=5.24, 95%CI: 1.28, 21.40), overtime everyday (OR=6.95, 95%CI: 1.71, 28.27), frequent wrist rotation (OR=1.95, 95%CI: 1.08, 3.51), and leaning back slightly (OR=2.94, 95%CI: 1.19, 7.28) associated with higher positive rates of fatigue. Conclusion The high positive rate of fatigue among live-line power distribution workers suggests severe fatigue issues. Extreme weather conditions, working overtime frequency, and maintaining wrist rotation and backward bending postures during work are main factors affecting their fatigue.

Objective: To investigate the relationship between 24 hour activity behaviors and fine motor development in preschool children, and to simulate the effects of reallocating time among different activity behaviors on fine motor development using isotemporal substitution analysis. Methods: From March to July 2022, a stratified cluster random sampling method was used to recruit 447 preschool children aged 3-6 years (254 boys and 193 girls) from Pingxiang City, Jiangxi Province. The 24 hour activity behaviors in preschool children were measured using ActiGraph wGT3-BT accelerometers and subjective sleep reports. Fine motor development was assessed using the Gesell Developmental Schedules. A component linear regression model was employed to analyze the impact of 24 hour activity behaviors on the development of fine motor activities, and the potential effects of adjusting activity behaviors were simulated through an isochoric substitution model. Results: The daily durations of sedentary behavior (SB) was ( 572.92 ±102.96) min (accounting for 39.79% of 24 h), the duration of light physical activity (LPA) was (131.21± 38.11 ) min ( 9.11% ), the duration of moderate to vigorous physical activity (MVPA) was (65.61±22.21) min (4.56%), and sleep duration was (670.65±57.58) min (46.82%). Sleep composition was positively associated with fine motor development ( β =2.74), while MVPA ( β =-0.84) and SB ( β =-1.93) compositions were negatively associated with fine motor development (all P <0.01). Isochoric substitution analysis showed that sleep had positive effects on the development of fine motor skills when replacing other activity behaviors (all P < 0.05), with the substitution effect for MVPA being the most significant and gradually increasing with the duration of substitution (60 min: β =28.66); sleep replacement of SB and LPA also showed positive effects (60 min: β =4.25, 2.00) (all P < 0.05). On the contrary, the substitution of sleep with MVPA showed negative effects (60 min: β =-7.86), and the substitution of LPA and SB with MVPA also showed negative effects (60 min: β =-5.65, -3.40) (all P <0.05). Conclusions The overall composition of 24 hour activity behaviors is associated with fine motor development in preschool children, with sleep playing a crucial role. Ensuring adequate sleep and optimizing the structure of activity behaviors may effectively promote the development of fine motor skills in preschool children.

ObjectiveTo establish steroid-induced osteonecrosis of the femoral head （SANFH） cell model by using dexamethasone （DEX）-induced bone marrow mesenchymal stem cells （BMSCs） and demonstrate that Gushing Granules （GSNs） exert an improving effect by activating the phosphatidylinositol-3-kinase/protein kinase B/B-lymphoma-2 gene related promoter （PI3K/Akt/Bad） signalling pathway. MethodsFirstly， SD rats were orally administered with drugs at a dose of 0.9 g·kg^-1 to prepare GSN-containing serum， and CCK-8 screening was used to determine the optimal dosage and duration of action. Then， BMSCs were cultured and treated with 1×10^-6 mol·L^-1 DEX， 10% GSN-containing serum， and inhibitor LY294002 of PI3K/Akt signalling pathway for 24 hours to model and group SANFH cells. Cell viability and proliferation were detected by using CCK-8 assay kit and EdU staining kit. Flow cytometry was used to detect cell apoptosis. An alkaline phosphatase （ALP） assay kit was employed to detect ALP expression. In order to detect the PI3K/Akt/Bad signalling pathway and protein and mRNA expression of apoptosis-related proteins such as apoptosis regulatory factors B-cell lymphoma-2 gene （Bcl-2）， and Bcl-2-associated X protein （Bax）， osteocalcin （OCN）， and Collagen Ⅰ， we used Western blot and Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR）. ResultsThe CCK-8 assay kit determined that the optimal dosage for GSN-containing serum is 10%， and the duration of action is 48 hours. After modelling and grouping the cells in each group， the detection results showed that the SANFH model group had significantly lower cell viability， cell proliferation， and ALP expression， as well as protein and mRNA expressions of PI3K， Akt， Bad， Bcl-2， OCN， and Collagen I compared to the blank group. The nucleic acid and protein levels of the Bax index and the cell apoptosis rate detected by flow cytometry significantly increased （P<0.05，P<0.01）. After treatment with GSN-containing serum， cell viability， cell proliferation， and ALP expression， as well as expressions of PI3K， Akt， Bad， Bcl-2， OCN， and Collagen Ⅰ nucleic acids and proteins were significantly increased， while the nucleic acid and protein levels of the Bax index and the cell apoptosis rate detected by flow cytometry significantly decreased（P<0.05，P<0.01）. Compared with the GSN drug-containing serum group， the simultaneous treatment with the inhibitor LY294002 and GSN drug-containing serum reversed the improvement effect of GSN. Specifically， the cell viability， cell proliferation， ALP expression， and the nucleic acid and protein levels of PI3K， Akt， Bad， Bcl-2， OCN， and Collagen Ⅰ were all significantly decreased， while the nucleic acid and protein levels of the Bax index and the cell apoptosis rate detected by flow cytometry were significantly increased （P<0.05， P<0.01）. ConclusionGSNs antagonize DEX-induced apoptosis of BMSCs by activating the PI3K/Akt/Bad signalling pathway， providing a scientific theoretical basis for the clinical treatment of SANFH with GSNs.

Background When live working line operators engage in upper limb operations, working for a long time with raising arms and the exposure to adverse ergonomic factors tend to increase muscle load, cause fatigue accumulation, and increase the risk of work-related musculoskeletal disorders (WMSDs). Objective To analyze work posture and associated muscle fatigue during executing breaking/connecting contact terminal, and identify adverse ergonomic factors of the work process. Methods This study recruited 10 volunteers to perform breaking/connecting contact terminal simulation. At a distance of 4.5, 3.5, and 2.5 m from the body to the wire, each performed the task 5 times. Visual 3D was used to analyze the kinematic data from motion capture. The surface electromyography (sEMG) signals of the deltoid, biceps, triceps, and brachioradialis were recorded during the simulation and analyzed for muscle fatigue using root mean square (RMS), median frequency (MF), and jointed EMG amplitude and spectrum analysis (JASA). After completion of each task, Borg scale was used to query the volunteers of their subjective fatigue. A 2-min rest was required between each distance. Results The kinematic data from motion capture showed that in the entire process of the task, the right upper limb was higher when lifting, with the right shoulder joint maintaining flexion and fluctuating periodically between abduction and adduction, external and internal rotation, the right elbow joint maintaining flexion and supination. The frequency of task cycle showed a significant effect on the Borg scale scores (P<0.001, partial \begin{document}$ {\eta }^{2} $\end{document}=0.464); the distance showed no significant effect on the Borg scale scores (P>0.05, partial \begin{document}$ {\eta }^{2} $\end{document}=0.002); their interaction effect was not significant (P>0.05, partial \begin{document}$ {\eta }^{2} $\end{document}=0.020). The results of the sEMG signals showed that at a distance of 4.5 m, the volunteers had the highest percentages of maximal voluntary electrical activation (MVE%) in the deltoid and right brachioradialis and the lowest MF values in the deltoid and left brachioradialis after completing 5 task cycles. The results of JASA showed that fatigue was observed in brachioradialis and deltoid after completing 5 task cycles at a distance of 4.5 m, the right deltoid and right brachioradialis at a distance of 3.5 m, in the brachioradialis, deltoid, and left bicep at a distance of 2.5 m. Conclusion The subjective fatigue of workers who engaged in breaking/connecting contact terminal elevates with more repetitive operations. Based on the sEMG and motion capture analysis, it can be found that improper distance between the workers and the target work area can increase the burden from poor posture and improper use of work equipment, and lead to muscle fatigue; the deltoid and brachioradialis are the key muscles of fatigue in this type of operation; changing the angle of the elbow joint and the shoulder joint during the process of the operation can affect the deltoid and brachioradialis exertion and loading.

Background Power grid is an important component of the national infrastructure. The occupational health issues among the workers in this industry are attracting great concern nationwide. Objective To investigate the prevalence of work-related musculoskeletal disorders (WMSDs) in neck and shoulder among the power distribution workers of power supply enterprises, and analyze the related influencing factors. Method In April 2023, a total of 1244 workers in 50 municipal power supply bureaus were randomly selected from the three provinces under China Southern Power Grid using cluster sampling method. The questionnaire used in the study was based on a revised Musculoskeletal Disorders Questionnaire and added ergonomic load of upper limb work. \begin{document}$ {\chi }^{2} $\end{document} test and logistic regression model were used to explore the influencing factors of neck pain and shoulder pain among the subjects. Results A total of 1244 valid questionnaires were recovered and the effective recovery rate was 90.87%(1244/1369). The positive rates of neck pain and shoulder pain were 45.5% (566 cases) and 36.3% (452 cases) respectively. The logistic regression analysis results showed that more than 20 years working age (OR=2.27, 95%CI: 1.39, 3.96; OR=2.56, 95%CI: 1.53, 4.26), often (OR=2.08, 95%CI: 1.35, 3.20; OR=2.40, 95%CI: 1.50, 3.58)/quite often (OR=2.96, 95%CI: 1.73, 5.04; OR=2.72, 95%CI: 1.49, 4.94) maintaining a forced posture, and working immediately after break (OR=1.72, 95%CI: 1.04, 2.85; OR=2.14, 95%CI: 1.19, 3.88) were associated with a higher positive rate of neck pain and shoulder pain respectively. Feeling sufficient rest (OR=0.61, 95%CI: 0.47, 0.80; OR=0.63, 95%CI: 0.50, 0.83) and opportunity to decide when to take breaks (OR=0.72, 95%CI: 0.53, 0.98; OR=0.62, 95%CI: 0.41, 0.93) were associated with a lower positive rate of neck pain and shoulder pain respectively. Conclusion The positive rates of neck pain and shoulder pain are high among power distribution workers. The main influencing factors included long working age, quite often maintaining a forced posture, and working immediately after break.

Background/Aims: Endoscopic radiofrequency ablation (ERFA) is a treatment option for superficial esophageal squamous cell neoplasia (ESCN), with a relatively low risk of stenosis; however, the long-term outcomes remain unclear. We aimed to compare the long-term outcomes of patients with widespread superficial ESCN who underwent endoscopic submucosal dissection (ESD) or ERFA. Methods: We retrospectively analyzed the clinical data of patients with superficial ESCN who underwent ESD or ERFA between January 2015 and December 2021. The primary outcome measure was recurrence-free survival. Results: Ninety-two and 33 patients with superficial ESCN underwent ESD and ERFA, respectively. The en bloc, R0, and curative resection rates for ESD were 100.0%, 90.2%, and 76.1%, respectively. At 12 months, the complete response rate was comparable between the two groups (94.6% vs 90.9%, p=0.748). During a median follow-up of 66 months, recurrence-free survival was significantly longer in the ESD group than in the ERFA group (p=0.004), while no significant differences in overall survival (p=0.845) and disease-specific survival (p=0.494) were observed.Preoperative diagnosis of intramucosal cancer (adjusted hazard ratio, 5.55; vs high-grade intraepithelial neoplasia) was an independent predictor of recurrence. Significantly fewer patients in the ERFA group experienced stenosis compare to ESD group (15.2% vs 38.0%, p=0.016). Conclusions The risk of recurrence was higher for ERFA than ESD for ESCN but overall survival was not affected. The risk of esophageal stenosis was significantly lower for patients who underwent ERFA.

Background/Aims: Endoscopic radiofrequency ablation (ERFA) is a treatment option for superficial esophageal squamous cell neoplasia (ESCN), with a relatively low risk of stenosis; however, the long-term outcomes remain unclear. We aimed to compare the long-term outcomes of patients with widespread superficial ESCN who underwent endoscopic submucosal dissection (ESD) or ERFA. Methods: We retrospectively analyzed the clinical data of patients with superficial ESCN who underwent ESD or ERFA between January 2015 and December 2021. The primary outcome measure was recurrence-free survival. Results: Ninety-two and 33 patients with superficial ESCN underwent ESD and ERFA, respectively. The en bloc, R0, and curative resection rates for ESD were 100.0%, 90.2%, and 76.1%, respectively. At 12 months, the complete response rate was comparable between the two groups (94.6% vs 90.9%, p=0.748). During a median follow-up of 66 months, recurrence-free survival was significantly longer in the ESD group than in the ERFA group (p=0.004), while no significant differences in overall survival (p=0.845) and disease-specific survival (p=0.494) were observed.Preoperative diagnosis of intramucosal cancer (adjusted hazard ratio, 5.55; vs high-grade intraepithelial neoplasia) was an independent predictor of recurrence. Significantly fewer patients in the ERFA group experienced stenosis compare to ESD group (15.2% vs 38.0%, p=0.016). Conclusions The risk of recurrence was higher for ERFA than ESD for ESCN but overall survival was not affected. The risk of esophageal stenosis was significantly lower for patients who underwent ERFA.

Background/Aims: Endoscopic radiofrequency ablation (ERFA) is a treatment option for superficial esophageal squamous cell neoplasia (ESCN), with a relatively low risk of stenosis; however, the long-term outcomes remain unclear. We aimed to compare the long-term outcomes of patients with widespread superficial ESCN who underwent endoscopic submucosal dissection (ESD) or ERFA. Methods: We retrospectively analyzed the clinical data of patients with superficial ESCN who underwent ESD or ERFA between January 2015 and December 2021. The primary outcome measure was recurrence-free survival. Results: Ninety-two and 33 patients with superficial ESCN underwent ESD and ERFA, respectively. The en bloc, R0, and curative resection rates for ESD were 100.0%, 90.2%, and 76.1%, respectively. At 12 months, the complete response rate was comparable between the two groups (94.6% vs 90.9%, p=0.748). During a median follow-up of 66 months, recurrence-free survival was significantly longer in the ESD group than in the ERFA group (p=0.004), while no significant differences in overall survival (p=0.845) and disease-specific survival (p=0.494) were observed.Preoperative diagnosis of intramucosal cancer (adjusted hazard ratio, 5.55; vs high-grade intraepithelial neoplasia) was an independent predictor of recurrence. Significantly fewer patients in the ERFA group experienced stenosis compare to ESD group (15.2% vs 38.0%, p=0.016). Conclusions The risk of recurrence was higher for ERFA than ESD for ESCN but overall survival was not affected. The risk of esophageal stenosis was significantly lower for patients who underwent ERFA.

Background/Aims: Endoscopic radiofrequency ablation (ERFA) is a treatment option for superficial esophageal squamous cell neoplasia (ESCN), with a relatively low risk of stenosis; however, the long-term outcomes remain unclear. We aimed to compare the long-term outcomes of patients with widespread superficial ESCN who underwent endoscopic submucosal dissection (ESD) or ERFA. Methods: We retrospectively analyzed the clinical data of patients with superficial ESCN who underwent ESD or ERFA between January 2015 and December 2021. The primary outcome measure was recurrence-free survival. Results: Ninety-two and 33 patients with superficial ESCN underwent ESD and ERFA, respectively. The en bloc, R0, and curative resection rates for ESD were 100.0%, 90.2%, and 76.1%, respectively. At 12 months, the complete response rate was comparable between the two groups (94.6% vs 90.9%, p=0.748). During a median follow-up of 66 months, recurrence-free survival was significantly longer in the ESD group than in the ERFA group (p=0.004), while no significant differences in overall survival (p=0.845) and disease-specific survival (p=0.494) were observed.Preoperative diagnosis of intramucosal cancer (adjusted hazard ratio, 5.55; vs high-grade intraepithelial neoplasia) was an independent predictor of recurrence. Significantly fewer patients in the ERFA group experienced stenosis compare to ESD group (15.2% vs 38.0%, p=0.016). Conclusions The risk of recurrence was higher for ERFA than ESD for ESCN but overall survival was not affected. The risk of esophageal stenosis was significantly lower for patients who underwent ERFA.