Background The job content of aircraft maintenance workers is complex, with high intensity and high requirements, and they are prone to work-related musculoskeletal disorders (WMSDs), but related research is relatively rare. Objective To investigate the positive rate of WMSDs among aircraft maintenance workers, evaluate ergonomic load, and analyze the risk factors of WMSDs. Methods We used a self-compiled questionnaire for WMSDs and the Quick Exposure Checklist (QEC) to investigate the basic situation, positive rate of WMSDs, and the ergonomic load of 2271 male maintenance workers in 6 departments of an aircraft maintenance company, including airline maintenance, overall overhaul, accessory/landing gear overhaul, engine overhaul, product customization, and power assist. We used a logistic regression model to analyze the risk factors of WMSDs in the neck, shoulder, hand/wrist, and lower back. Results The positive rate of WMSDs in the past 12 months was 70.4% (1598/2271) and the positive rate of WMSDs in different body parts ranged from 6.6% to 49.5%, with the top three parts of lower back, neck, and knee, respectively. There were statistically significant differences in the positive rate among different departments (P<0.05). The average QEC scores for neck, hand/wrist, and back (static) were moderate, while those for shoulder and back (dynamic) were high, and the body part specific positive rate of WMSDs increased with the increase of ergonomic load level. Working years (5-<10 years, ≥20 years), working with back flexed or twisted or side bent (moderately, excessively), high maximum force level exerted by one hand, and feeling difficult (sometimes, often) and stressful (moderately, very) while working were associated with higher risks of lower back pain (OR=1.486, 1.505; 2.151, 3.769; 1.637; 2.110, 2.407; 1.637, 1.794; P<0.05). Working years (15-<20 years, ≥20 years), working with head/neck bent or twisted (occasionally, continuously), feeling difficult (sometimes) and stressful (very) while working were associated with higher risks of neck pain (OR=1.731, 1.586; 3.732, 8.341; 1.633; 1.696; P<0.05). Working years (15-<20 years, ≥20 years), working with hands in a high position (at shoulder or above), very frequent shoulder/arm movements, feeling difficult (sometimes, often) and stressful (moderately, very) while working were associated with higher risks of shoulder pain (OR=1.587, 1.709; 1.299; 1.521; 1.643, 2.239; 1.659, 1.977; P<0.05). Working with wrist at deviated or bent angle, high repetition of similar movements, feeling difficult (sometimes, often) and stressful (moderately, very) while working were associated with higher risks of hand/wrist pain (OR=1.692; 1.670; 1.827, 2.884; 2.190, 2.625; P <0.05) . Physical exercise after work (≥3 times·week⁻¹) was associated with a lower risk of neck pain (OR=0.582, P<0.05). Shift workers were at a lower risk of shoulder pain and hand/wrist pain (OR=0.737 and 0.554, P<0.05). Conclusion The high positive rate of WMSDs symptoms among aircraft maintenance workers is related to individual, occupational ergonomic, and psychological factors, and active prevention and intervention should be taken.

Objective To assess the current state and influencing factors of multi-site work-related musculoskeletal disorders (WMSDs) among front-line employees in the assembly workshop of an automobile manufacturing enterprise. Methods A total of 394 front-line workers in the assembly workshop of an automobile manufacturing enterprise in Beijing City were selected as the research subjects using the judgmental sampling method. The Chinese version Musculoskeletal Disorders Questionnaire was used to assess the presence of WMSDs over the past 12 months in nine body regions: neck, shoulders, upper back, lower back, elbows, wrists, hips and thighs, knees, ankles and feet. The multivariable logistic regression was employed to investigate the influencing factors. Results The detection rate of overall WMSDs was 32.7% (129/394), with the top three single-site WMSDs being in the neck, shoulders, and lower back, and their detection rates were 14.0%, 12.7% and 9.6%, respectively. The detection rate of multi-site WMSDs was 17.8% (70/394). The result of multivariable logistic regression analysis revealed that workers who turned or bent their upper body while keeping their legs stationary, frequently performed wrist flexion/extension/lateral bending/rotation, or stood for prolonged period of time had significantly higher risks of developing multi-site WMSDs compared with those who did not (all P<0.05). Workers who perceived uncomfortable workplace lighting had higher risk of multi-site WMSDs than those who perceived it as comfortable (P<0.01). Conclusion The development of multi-site WMSDs among workers in the assembly workshop of this automobile manufacturing enterprise is strongly related to poor working postures at work.

Background During urbanization, the passenger load on urban public transport systems continues to increase, exposing bus drivers to a high risk of musculoskeletal disorders (MSDs). This occupational health issue may also potentially compromise public transport safety. Objective To investigate the prevalence of MSDs among bus drivers in a first-tier city and to explore associated influencing factors. Methods A self-administered questionnaire survey was conducted from December 2024 to March 2025 among 1300 bus drivers in a bus company. Data were collected on general demographic information, occupational activities, and MSDs indicators. A total of 1268 valid questionnaires were returned, yielding a response rate of 97.5%. Descriptive statistics were used to analyze the distribution characteristics of MSDs. Pearson χ² tests were employed to examine the association between MSDs prevalence and individual/occupational characteristics. Logistic regression was performed to identify the influencing factors of MSDs. Results The survey revealed that the prevalence of MSDs among the bus drivers was 28.5%, with the highest prevalence in the 41–50 years age group (30.5%). The conditions primarily affected the cervical spine (60.5%) and lumbar spine (61.9%), with some cases involving multiple sites. The logistic regression model indicated that the following factors were associated with a higher risk of MSDs: frequent smoking (OR=1.477), poor or moderate self-reported health status (OR=4.422), 11–20 years of service (OR=1.749), daily cumulative driving time ≥361 min (OR=1.616), frequent whole-body fatigue during driving (OR=2.077), occasional whole-body fatigue during driving (OR=1.873), feeling tense during driving (OR=1.518), fatigue after work (OR=2.485), work-related stress (OR=1.882), and prolonged smartphone use with head-down posture (OR=1.671). Conversely, occasional exercise (OR=0.713)/frequent exercise (OR=0.569), driving intervals ≥21 min per round (OR=0.645), and perceiving the driving seat comfortable (OR=0.429) were associated with a lower risk of MSDs. Conclusion Physical exercise, smoking, years of service, daily cumulative driving time, driving intervals per round, prolonged smartphone use with head-down posture, self-reported health status, and psychological factors such as work-related stress are influencing factors for MSDs among bus drivers. Drivers should increase physical exercise and change unhealthy living habits. Employers should optimize working conditions, arrange reasonable driving schedules, and foster a positive work environment to reduce MSDs prevalence.

Background During urbanization, the passenger load on urban public transport systems continues to increase, exposing bus drivers to a high risk of musculoskeletal disorders (MSDs). This occupational health issue may also potentially compromise public transport safety. Objective To investigate the prevalence of MSDs among bus drivers in a first-tier city and to explore associated influencing factors. Methods A self-administered questionnaire survey was conducted from December 2024 to March 2025 among 1300 bus drivers in a bus company. Data were collected on general demographic information, occupational activities, and MSDs indicators. A total of 1268 valid questionnaires were returned, yielding a response rate of 97.5%. Descriptive statistics were used to analyze the distribution characteristics of MSDs. Pearson χ² tests were employed to examine the association between MSDs prevalence and individual/occupational characteristics. Logistic regression was performed to identify the influencing factors of MSDs. Results The survey revealed that the prevalence of MSDs among the bus drivers was 28.5%, with the highest prevalence in the 41–50 years age group (30.5%). The conditions primarily affected the cervical spine (60.5%) and lumbar spine (61.9%), with some cases involving multiple sites. The logistic regression model indicated that the following factors were associated with a higher risk of MSDs: frequent smoking (OR=1.477), poor or moderate self-reported health status (OR=4.422), 11–20 years of service (OR=1.749), daily cumulative driving time ≥361 min (OR=1.616), frequent whole-body fatigue during driving (OR=2.077), occasional whole-body fatigue during driving (OR=1.873), feeling tense during driving (OR=1.518), fatigue after work (OR=2.485), work-related stress (OR=1.882), and prolonged smartphone use with head-down posture (OR=1.671). Conversely, occasional exercise (OR=0.713)/frequent exercise (OR=0.569), driving intervals ≥21 min per round (OR=0.645), and perceiving the driving seat comfortable (OR=0.429) were associated with a lower risk of MSDs. Conclusion Physical exercise, smoking, years of service, daily cumulative driving time, driving intervals per round, prolonged smartphone use with head-down posture, self-reported health status, and psychological factors such as work-related stress are influencing factors for MSDs among bus drivers. Drivers should increase physical exercise and change unhealthy living habits. Employers should optimize working conditions, arrange reasonable driving schedules, and foster a positive work environment to reduce MSDs prevalence.

Objective:To investigate the status of work-related musculoskeletal disorders (WMSDs) in male large-scale mechanical maintenance workers, and to explore the relationship between WMSDs and thyroid indexes.Methods:From April to July 2022, male front-line maintenance workers in a large-scale mechanical maintenance enterprise who participated in occupational health examination were selected as the study subjects ( n=2036). The occurrence of WMSDs was investigated by questionnaire. The levels of triiodothyronine (T3), thyroxine (T4) and thyroid stimulating hormone (TSH) in serum were detected. χ2 test, t-test and Mann-Whitney U test were used to detect thyroid diseases and hormone levels of workers in WMSDs group and non-WMSDs group, and binary logistic regression model was used to analyze the relationship between thyroid disease, T3, T4, TSH and WMSDs. Results:The incidence of WMSDs among the male large-scale mechanical maintenance workers was 73.18% (1490/2036). The rate of thyroid disease in WMSDs group was higher than that in non-WMSDs group [8.26% (123/1490) vs. 4.95% (27/546), χ 2=6.42, P=0.011], and the TSH value was lower than that in non-WMSDs group[1.66 (1.23, 2.26) μIU/ml vs. 1.75 (1.30, 2.42) μIU/ml, Z=-2.40, P=0.019]. There were no significant differences in the levels of T3, T4 and abnormal levels of 3 hormones between the two groups ( P>0.05). After accounting for individual and occupational factors, workers with thyroid disease had an increased risk of WMSDs ( OR=1.656, 95% CI: 1.072-2.559, P=0.023), while workers with increased TSH had a decreased risk of WMSDs ( OR=0.897, 95% CI: 0.823-0.977, P=0.013) . Conclusion:The incidence of WMSDs in male workers of large-scale mechanical maintenance is high, and its incidence may be related to thyroid index. Thyroid disease may be a risk factor for WMSDs, and increased TSH may be a protective factor for WMSDs.

Objective To explore the application effect of"5E"teaching mode combined with deep learning charac-teristics in residential training teaching of general subjects.Methods From July to December 2024,the"5E"teaching mode combined with the characteristics of deep learning was implemented in 30 general practitioners being trained in three standardized training bases of residents in Qiqihar City,and the scores of self-learning ability and critical thinking ability of students before and after the implementation of teaching were tested by paired t-test.Re-sults After teaching,the scores of self-learning ability and critical thinking ability of the general training students were higher than those before teaching,and the differences were statistically significant(P＜0.05).Conclusion"5E"teaching mode can improve the learning effect and clinical practice ability of general training students.

Objective To explore the application effect of"5E"teaching mode combined with deep learning charac-teristics in residential training teaching of general subjects.Methods From July to December 2024,the"5E"teaching mode combined with the characteristics of deep learning was implemented in 30 general practitioners being trained in three standardized training bases of residents in Qiqihar City,and the scores of self-learning ability and critical thinking ability of students before and after the implementation of teaching were tested by paired t-test.Re-sults After teaching,the scores of self-learning ability and critical thinking ability of the general training students were higher than those before teaching,and the differences were statistically significant(P＜0.05).Conclusion"5E"teaching mode can improve the learning effect and clinical practice ability of general training students.

Objective:To investigate the status of work-related musculoskeletal disorders (WMSDs) in male large-scale mechanical maintenance workers, and to explore the relationship between WMSDs and thyroid indexes.Methods:From April to July 2022, male front-line maintenance workers in a large-scale mechanical maintenance enterprise who participated in occupational health examination were selected as the study subjects ( n=2036). The occurrence of WMSDs was investigated by questionnaire. The levels of triiodothyronine (T3), thyroxine (T4) and thyroid stimulating hormone (TSH) in serum were detected. χ2 test, t-test and Mann-Whitney U test were used to detect thyroid diseases and hormone levels of workers in WMSDs group and non-WMSDs group, and binary logistic regression model was used to analyze the relationship between thyroid disease, T3, T4, TSH and WMSDs. Results:The incidence of WMSDs among the male large-scale mechanical maintenance workers was 73.18% (1490/2036). The rate of thyroid disease in WMSDs group was higher than that in non-WMSDs group [8.26% (123/1490) vs. 4.95% (27/546), χ 2=6.42, P=0.011], and the TSH value was lower than that in non-WMSDs group[1.66 (1.23, 2.26) μIU/ml vs. 1.75 (1.30, 2.42) μIU/ml, Z=-2.40, P=0.019]. There were no significant differences in the levels of T3, T4 and abnormal levels of 3 hormones between the two groups ( P>0.05). After accounting for individual and occupational factors, workers with thyroid disease had an increased risk of WMSDs ( OR=1.656, 95% CI: 1.072-2.559, P=0.023), while workers with increased TSH had a decreased risk of WMSDs ( OR=0.897, 95% CI: 0.823-0.977, P=0.013) . Conclusion:The incidence of WMSDs in male workers of large-scale mechanical maintenance is high, and its incidence may be related to thyroid index. Thyroid disease may be a risk factor for WMSDs, and increased TSH may be a protective factor for WMSDs.

Background Bus drivers are a high-risk group for work-related musculoskeletal disorders (WMSDs). There are a large number of bus drivers in mega-cities. High volumes of passenger traffic and complexity of road conditions may elevate their risk of WMSDs, but there are few studies related to this group. Objective To investigate the prevalence of WMSDs among bus drivers in a mega-city and to analyze potential influencing factors. Methods Based on cross-sectional study design and self-administered questionnaire, the prevalence of WMSDs in past 12 months were estimated by stratified cluster sampling among bus drivers in a mega-city. Pearson χ² and logistic regression models were used to analyze the influencing factors for the body regions with a high prevalence. Results The overall prevalence of WMSDs in past 12 months among bus drivers in a mega-city was 49.5% (551/1113). The prevalence of WMSDs by body regions ranged from 4.0% to 38.5%, and led by neck pain (38.5%), lower back pain (25.5%), and shoulder pain (20.8%). The results of logistic regression showed that the risk factors for neck pain were age (>50 years), smoking, tiredness after work (moderate, severe), long sitting (frequently), awkward postures (sometimes, often, frequently), overtime(occasionally, often), workplace temperature (uncomfortable), and noise (severe) (OR=2.014、1.577、2.793、3.025、2.708、2.032、3.406、2.746、1.442、2.998、1.456、3.506；P<0.05); the lower back pain risk factors were current work experience (6-10 years, 11-15 years, and 16-20 years), smoking, tiredness after work (moderate, severe), and awkward postures(sometimes, often, frequently)(OR=1.777、2.130、2.400、1.503、2.951、3.364、1.836、4.569、2.786，P<0.05); and the shoulder pain risk factors were age (46-50 years, and >50 years), smoking, tiredness after work (moderate, severe), vehicle type (hybrid power, diesel oil), awkward postures (often, frequently), overtime (often), and workplace temperature (uncomfortable) (OR=1.737、2.357、1.553、2.259、2.489、1.659、3.295、2.777、3.320、2.266、1.426，P<0.05). Identified protective factors for neck and lower back pain were off-duty physical activity (1-2 times per week, and ≥3 times per week) (OR=0.553、0.470、0.586、0.485，P<0.05). Conclusion Nearly half of the bus drivers in the mega-city report symptoms of WMSDs, mainly in the neck, lower back, and shoulders. The prevalence is related to individual and occupational factors, and prevention and intervention measures should be actively taken.

ObjectiveTo identify the prototypical components and metabolites absorbed into blood and cerebrospinal fluid of Schisandrae Chinensis Fructus（SCF） based on sequential metabolism combined with liquid chromatography-mass spectrometry. MethodBlood and cerebrospinal fluid samples of integrated metabolism， intestinal metabolism and hepatic metabolism were collected from male SD rats after gavage and in situ intestinal perfusion administration， and ultra-performance liquid chromatography-quadrupole/electrostatic field orbitrap high-resolution mass spectrometry（UPLC Q-Exactive Orbitrap MS） was used to analyze and compare the differences in the spectra of SCF extract， blank plasma， administered plasma， blank cerebrospinal fluid and administered cerebrospinal fluid with ACQUITY UPLC BEH Shield RP18 column（2.1 mm×100 mm， 1.7 µm）， the mobile phase was acetonitrile（A）-0.1% formic acid aqueous solution（B） for gradient elution（0-7 min， 95%B； 7-12 min， 95%-35%B； 12-17 min， 35%-15%B； 17-20 min， 15%-12%B； 20-22 min， 12%-5%B； 22-23 min， 5%B； 23-25 min， 5%-95%B； 25-28 min， 95%B）. And heated electrospray ionization（HESI） was used with positive and negative ion modes， the scanning range was m/z 100-1 500. The prototypical constituents and their metabolites absorbed into blood and cerebrospinal fluid of SCF were identified according to the retention time， characteristic fragments， molecular formulae and the information of reference substances. ResultA total of 42 chemical components were identified in the extract of SCF， including lignans， flavonoids， amino acids， tannins， and others， of which lignans were the main ones. A total of 27 prototypical components and 14 metabolites were identified in plasma samples from different sites. A total of 15 prototypical components and 9 metabolites were identified in cerebrospinal fluid. The main metabolic reactions involved in the formation of metabolites were mainly demethylation， methylation， demethoxylation and hydroxylation. ConclusionThrough the systematic identification of the prototypical components and metabolites of SCF in rats， it provides data support for further better exploring the material basis of SCF in the treatment of central nervous system diseases.