Objective To evaluate the role of distortion product otoacoustic emissions (DPOAE) testing in evaluating early hearing loss among noise-exposed workers. Methods A total of 174 noise-exposed workers in a metal shipbuilding enterprise were selected as the research subjects by the convenience sampling method. Pure tone audiometry (PTA), DPOAE and the level of noise exposure were conducted on the workers. The rank correlation analysis was used to analyze the correlation between DPOAE amplitude and PTA threshold. The multilevel model was used to analyze the effects of gender, age, noise exposure intensity, cumulative noise exposure (CNE), hearing loss classification and PTA threshold on DPOAE results. Results At the frequencies of 0.50, 1.00, 2.00, 3.00, 4.00, 6.00 and 8.00 kHz, the DPOAE amplitude was negatively correlated with the PTA threshold (rank correlation coefficients were -0.12, -0.48, -0.47, -0.18, -0.23, -0.44, -0.19, respectively, all P<0.01). At the most frequencies, DPOAE amplitude was negatively correlated with age and CNE (all P<0.05). The results of multilevel model analysis showed that there were significant differences in DPOAE amplitudes at certain frequencies across gender, age, noise intensity, CNE, and hearing loss classification (all P<0.05). Significant differences in DPOAE responses were found among different CNE and hearing loss groups (all P<0.01). Conclusion DPOAE testing can objectively reflect the hearing status of noise-exposed workers and could be considered for inclusion in routine hearing monitoring to facilitate early detection of noise-induced hearing loss.

Objective: To investigate the distribution of pupil diameter and its association with myopia in school age children, providing ideas into the mechanisms of the role of pupil diameter in the onset and development of myopia. Methods: Adopting a combination of stratified cluster random sampling and convenience sampling method, 3 839 children from six schools in Shandong Province were included in September 2021. Pupil diameters distribution was analyzed by age, sex, and myopic status. Pearson correlation analysis was used to assess the relationship between pupil diameter and cycloplegic spherical equivalent (SE), as well as axial length (AL) and other variables. Propensity score matching (PSM) was applied to match myopic and non myopic children at a 1∶1 ratio based on age and sex. A generalized linear model (GLM) was constructed with pupil diameter as the dependent variable to identify independent factors influencing pupil size and its association with myopia. Results: The mean pupil diameter of school age children was (5.77±0.80)mm. Pupil diameter exhibited a significant increasing trend with age ( F =49.34， P trend ＜ 0.01). Myopic children had a significantly larger mean pupil diameter [(6.10±0.73)mm] compared to non myopic children [(5.62±0.79)mm] with a statistically significant difference( t=18.10, P <0.01). Multivariable GLM analysis, adjusted for age, amplitude of accommodation, and uncorrected visual acuity, revealed a negative correlation between pupil diameter and cycloplegic SE (before PSM: β =-0.089, after PSM: β =-0.063, both P ＜0.01). Conclusions Myopic school age children exhibite larger pupil diameters than their non myopic counterparts. Pupil diameter may serve as a potential indicator for monitoring myopia development in school age children.

At present, the C-arm structure accelerators commonly used in radiotherapy equipment are complex in operation and have potential safety hazards when realizing non-coplanar treatment. By combining with medical robotic arm technology, a spherical radiotherapy accelerator motion system is designed. The beam module is clamped by the medical robotic arm structure to achieve three-dimensional multi-angle irradiation treatment within the non-coplanar angle range. Firstly, the rotating mechanism, beam module, and MLC module of the spherical radiotherapy equipment are designed. Then, the double-plane counterweight method is used to calculate the dynamic balance of the equipment, ensuring that the beam center point does not rotate during the treatment process. Finally, the strength check and reliability analysis of the transmission component gear are conducted. The results show that the designed spherical radiotherapy accelerator motion system can meet the requirements of stable, accurate, and fast precision radiotherapy, which is conducive to improving the treatment efficiency.
Particle Accelerators/instrumentation* ; Equipment Design ; Reproducibility of Results ; Radiotherapy/instrumentation*

Objective To investigate the prevalence and risk factors of work-related musculoskeletal disorders (WMSDs) among construction workers. Methods A total of 5 783 workers were selected as participants from 12 construction companies in Guangdong Province, Guangxi Zhuang Autonomous Region and Zhejiang Province using a convenient sampling method. The revised Musculoskeletal Disorders Questionnaire was used to investigate the prevalence and influencing factors of WMSDs. Results The prevalence of WMSDs was 27.4% among the construction workers. The prevalence of WMSDs in shoulder, neck, waist/lower back and hand/wrist was 10.6%, 9.5%, 9.5% and 9.4% respectively, which was higher than that in other body parts. Bianry logistic regression analysis showed that the risk of WMSDs in construction workers with junior high school education and below was higher than that of high school/ college and above (P<0.05). The risk of WMSDs was higher in drinkers than that in non-drinkers (P<0.01). The worse the health status of construction workers, the higher the risk of WMSDs (P<0.01). The risk of WMSDs in those who exercised once or twice a month was lower than that in those who did not exercise (P<0.05). The risk of WMSDs was higher in construction workers with longer working hours in uncomfortable postures and greater back bending amplitude at work (all P<0.01). The risk of WMSDs in construction workers with hands holding above the shoulder was higher than that with hands below the shoulder (P<0.05). Construction workers who repeated the same work daily, involved in high-temperature work, often worked overtime, had insufficient rest time, and had a shortage of department personnel had a relatively high risk of WMSDs (all P<0.01). Conclusion The prevalence of WMSDs among the construction workers was relatively high, and the most common WMSDs occurred in shoulder, neck, waist/lower back and hand/wrist. Individual characteristic, work type, work posture and work organization are the influencing factors of WMSDs. Comprehensive measures, especially ergonomic measures based on personal and occupational characteristics should be taken to reduce the risk of WMSDs among construction workers.

Objective To analyze the effect of hand transmitted vibration on fingertip thermotactile perception threshold (TPT) among grinding workers in a sports equipment manufacturing enterprise. Methods A total of 151 male grinding workers from a sports equipment manufacturing enterprise in Guangdong Province were enrolled in the vibration exposure group, and 51 male workers without hand-transmitted vibration exposure were enrolled in the control group, using the judgment sampling method. Basic health conditions of the workers were surveyed in both groups. The TPTs of the distal phalanges of the index and little fingers on both hands were tested using an HVLab thermal perception tester. Results The detection rates of finger numbness and tingling among workers in the vibration exposure group were higher than those in the control group (92.1% vs 7.8% and 59.6% vs 0.0%, respectively, both P<0.01). The detection rates of numbness or tingling of different fingers in the vibration exposure group descended in the following order: index finger, middle finger, ring finger, thumb and little finger. The hot threshold of the index finger and little finger increased (all P<0.01), while the cold threshold decreased (all P<0.01) in the vibration exposure group, compared with the control group. The results of generalized linear regression analysis showed that with the increase of the duration of hand-transmitted vibration, the hot threshold of the index finger and the little finger of both hands increased (all P<0.01), and the cold threshold decreased (all P<0.01). The hot thresholds of workers with numbness of both the index fingers and left little finger were higher than those of workers without numbness of the same finger (all P<0.05). The hot threshold of workers with tingling of the left index finger was higher than those without tingling (P<0.05). The cold thresholds of workers with tingling of the both index fingers and left little finger were lower than those without tingling of the same finger (all P<0.05). The hot threshold of the right little finger increased with age (P<0.01), while the cold thresholds of both little fingers decreased with age (all P<0.01). Conclusion Hand-transmitted vibration exposure increases fingertip hot threshold and decreases fingertip cold threshold of workers exposed to hand-transmitted vibration. Years of service in hand-transmitted vibration work, finger numbness or tingling, and age were influencing factors of TPT. Fingertip TPT examination can be used to assist in the early detection of vibration-induced nerve injury in workers exposed to hand-transmitted vibration.

Objective To understand the characteristics of occupational noise hazards in key industries in Huizhou City. Methods A total of 247 enterprises from 13 key industries in Huizhou City were selected as the research subjects using the stratified judgment sampling method. The worksite survey of occupational health and workplace noise intensity and spectrum monitoring were conducted at key work sites using "questionnaires and on-site inspections" method. Results The rate of noise intensity exceeding national standards was 53.4% (132/247). The median, 25th and 75th percentile of noise pressure levels in workplaces and worksites were 85.1 (81.2, 91.2)and 82.5 (78.8, 86.3) dB(A), respectively. The high-noise workplaces accounted for 50.0% (479/958). The rate of noise intensity exceeding national standard at work sites was 32.9% (303/921). The sound pressure level of noise at work sites was positively correlated with sound pressure level of noise sources (Spearman correlation coefficient=0.73, P<0.01). The top three high-risk work sites for exceeding national noise standards were grinding, frame nailing, and material cutting, with exceedance rates of 84.6%, 81.3%, and 62.8%, respectively. The frequency characteristics of the top ten high-risk work sites were mainly high-frequency noise. There were significant differences in noise spectrum characteristics among different workpiece materials used in similar types of work sites (all P<0.05), though high-frequency noise remained dominant. Conclusion Noise hazards in workplaces of key industries in Huizhou City are relatively severe. Continuous attention should be given to key work sites with high over-standard rate, such as grinding, frame nailing, and material cutting, and noise control strategies should be developed based on frequency spectrum characteristics.

ObjectiveTo analyze the spectrum distribution characteristics of high-intensity productive noise in key industries in Guangdong Province. Methods A total of 2 806 enterprises in 21 prefecture-level cities in Guangdong Province were selected as the study subjects using the stratified sampling method. On-site investigations were conducted in workplaces. Noise in workplaces and work-sites, and the noise spectrum of the workplaces with sound pressure level ≥85.0 dB(A) were detected. Results The noise of a total of 23 076 workplaces and 20 969 work sites from 30 key industries were monitored. The median (M) and 25th and 75th percentiles (P₂₅, P₇₅) of workplace sound pressure level were 82.3 (78.6, 86.5) dB(A). The rate of the noise exceeded national standard was 30.4%. The sound pressure level M (P₂₅, P₇₅) of work-site was 78.6 (70.0, 83.5) dB(A). The rate of the noise exceeded national standard was 18.0%. Workplace noise and work site noise were positively correlated (Spearman correlation coefficient=0.86, P<0.01). The rate of the noise exceeded national standard was 46.5% in key work sites where the rate of noise exceeded the national standard was ≥25.0%, and corresponding rate of the workplace noise exceeded national standard was 58.1%. The noise spectrum result of 5 636 workplaces sound pressure level>85.0 dB(A) showed that most of the noise source was from grinding machines (441 cases), and the highest average sound pressure level of noise source was from screening machines [93.0 dB(A)]. Cluster analysis results showed that the main noise sources could be divided into three categories, including wideband noise with levels >80.0 dB in all frequency bands except 8 000.0 Hz, medium-high-frequency noise with the highest sound pressure level at 1 000.0, 2 000.0, and 4 000.0 Hz and low frequencies <75.0 dB, and medium-low-frequency noise below 500.0 Hz with sound pressure level >85.0 dB. Conclusion The rate of the noise exceeded national standard in workplace of key industries in Guangdong Province is high, involving a wide range of industries, with high sound pressure levels and obvious spectrum characteristics of corresponding noise sources. Corresponding noise control strategies can be formulated based on different spectrum characteristics and magnitudes.

Objective:To investigate the common viral pathogen spectrum of acute respiratory infection (ARI) cases in Changshu city.Methods:Nasopharyngeal swab samples from outpatients and inpatients in five sentinel hospitals in Changshu city from January 2022 to October 2023 were collected. Real-time fluorescent quantitative polymerase chain reaction was used to detect the nucleic acids of influenza virus (Flu) and respiratory syncytial virus (RSV), adenovirus (AdV), human rhinovirus (HRV), human parainfluenza virus (HPIV), enterovirus (EV), human coronavirus (HCoV), human metapneumovirus (HMPV), and human bocavirus (HBoV).Results:Of the 1 936 ARI cases, 18.1% (350/1 936) were tested positive for viral nucleic acid. Flu had the highest detection rate (7.1%), followed by HBoV (3.7%), AdV (1.9%) and RSV (1.6%). The virus detection rate was significantly different among different age groups and seasons. In March 2023, the total virus detection rate was the highest (47.6%), mainly Flu. Flu showed unimodal prevalence in spring and winter. The prevalence trend of HBoV and HCoV was consistent, and the detection rate of HBoV (5.43%) was higher than that of HCoV (2.45%), both of which peaked in summer. RSV prevalence peaks in autumn (4.5%). The detection rate of children aged 0-5 years was the highest, reaching 33.3%.Conclusions:The main ARI pathogens in Changshu city from 2022 to 2023 were Flu, HBoV, AdV and RSV.

The incidence of osteoporotic thoracolumbar vertebral fracture (OTLVF) in the elderly is gradually increasing. The kyphotic deformity caused by various factors has become an important characteristic of OTLVF and has received increasing attention. Its clinical manifestations include pain, delayed nerve damage, sagittal imbalance, etc. Currently, the definition and diagnosis of OTLVF with kyphotic deformity in the elderly are still unclear. Although there are many treatment options, they are controversial. Existing guidelines or consensuses pay little attention to this type of fracture with kyphotic deformity. To this end, the Lumbar Education Working Group of the Spine Branch of the Chinese Medicine Education Association and Editorial Committee of Chinese Journal of Trauma organized the experts in the relevant fields to jointly develop Clinical guidelines for the diagnosis and treatment of osteoporotic thoracolumbar vertebral fractures with kyphotic deformity in the elderly ( version 2024), based on evidence-based medical advancements and the principles of scientificity, practicality, and advanced nature, which provided 18 recommendations to standardize the clinical diagnosis and treatment.

Objective:To investigate genetic characteristics of human rhinovirus (HRV) in adult inpatients with pneumonia in autumn and winter in Bengbu, Anhui province, 2021.Methods:The pharyngeal swabs of inpatients with pneumonia in Bengbu were collected for the detection of 14 common respiratory pathogens by Real-time PCR during September to December 2021. VP4/VP2 coding regions of HRV positive samples were amplified by nested PCR and phylogenetic tree was constructed using MEGA7.0.Results:A total of 146 samples were collected from inpatients with pneumonia; 35.62% (52/146) samples were positive with at least one pathogen. The four viruses with high detection rate were HRV, adenovirus, human coronavirus OC43 and influenza B virus. HRV positive samples accounted for 44.23% (23/52) of the positive samples, among which 9 cases (39.13%, 9/23) co-infected with HRV. Phylogenetic analysis found that HRV infection were dominated by HRV-A and HRV-B groups. The analysis based on clinical syndrome found that the white blood cells count and the proportion neutrophils of patients with HRV co-infection were higher that of HRV single infection. The proportion of patients with hypertension, diabetes, mechanical ventilation and poor prognosis in the HRV co-infection group were higher than that of HRV single infection group ( P<0.05). Conclusions:HRV is the predominant pathogen among the adult inpatients with pneumonia in Bengbu. HRV-A and HRV-B groups are common. Patients accompanied by hypertension, diabetes were easily co-infected with HRV. Patients coinfeted with HRV are more likely to be mechanical ventilation and poor prognosis.