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 construct N6-methyladenosine related long non-coding RNA(LncRNA)pairing model for renal cell carcinoma based on bioinformatics analysis of the cancer ganome atlas(TCGA)database and to explore its prognosis value.Methods Transcriptome data of RNA-sep for renal cell carcinoma and its related clinical information were downloaded from the TCGA database.Perl software was used to organize and separate LncRNA and messenger RNA(mRNA)from the transcriptome data.A total of 564 tissues from renal cell carcinoma cases and 72 normal tissues were obtained,and thus 540 renal cancer patients were eventually included.Random data table method was used to divide 540 patients with renal cancer into a training group(n=275)and a validation group(n=265)by caret.M6A related LncRNA pairing models were established based on the single factor and multivariate COX regression analysis.The risk assessment equation was obtained using the LASSO regression algorithm.The risk scores were calculated based on this equation,and the optimal critical point of the median risk value was applied to divide all patients into high-risk and low-risk groups.Kaplan-Meier survival analysis was used to make a survival curve for the differences between high and low risk groups in the overall sample.The gene ontology(GO)and Kyoto encyclopedia of genes and genomes(KEGG)pathway enrichment analyses were conducted using the Cluster Profiler software package.The relationship between N6-methyladenosine related LncRNA pairing model and immune cell infiltration was analyzed by R software.Results Kaplan-Meier survival analysis showed the total survival time of patients in the low-risk group was significantly higher than that of patients in the high-risk group of the training group(P<0.05).Compared with high risk group,the overall survival time of patients(G1～2,G3～4,Ⅰ～Ⅱ,or Ⅲ～Ⅳ,age≤65 years,or patients>65 years old)in low risk group was higher(P<0.05).Differential gene enrichment analysis was obtained for high and low risk groups,which mainly enriched with many differential genes such as muscle contraction,rhabdomytic cell differentiation,myofibril,receptor activation activity,and vascular smooth muscle contraction.The highest driver genes in high risk group and low risk group exhibited mutation frequency and mutation information,and their risk score was positively correlated with the degree of T cell and plasma cell infiltration(r=0.638,P=0.001).Conclusion Bioinformatics-based analysis of the N6-methyladenosine related LncRNA pairing models can be helpful to predict the prognosis of patients with renal cancer.It provides new ideas for the prognosis evaluation and optimal treatment strategy of renal cancer,and contributes to further analyzing the molecular mechanism of the occurrence and development of gastric cancer in the future.

ObjectiveTo explore the influencing factors of occupational hand-arm vibration disease (OHAVD) caused by handheld workpiece polishing. Methods A total of 222 OHAVD patients (case group), 275 hand-transmitted vibration-exposed workers (exposed group) and 243 healthy workers without hand-transmitted vibration exposure (control group) in a sports equipment manufacturing enterprise were selected as the study subjects using the convenience sampling method. Worksite survey of occupational health was conducted on these three groups, and the human vibration measurement equipment was used to measure the vibration exposure level of handheld vibration among the study subjects. The 8-hour energy equivalent frequency-weighted vibrating acceleration ［A(8)］ and cumulative vibration exposure level (CVEL) were calculated. Results The prevalence of coldness, numbness, tingling fingers, and vibration-induced white finger was higher in the exposed group and the case group compared with the control group (all P<0.05). The prevalence of the above-mentioned hand symptoms was higher in the case group compared with the exposed group (all P<0.05). The A(8) and CVEL levels of the study subjects in the case group were higher than those in the exposed group (all P<0.05). Binary logistic analysis result showed that age and CVEL were both influencing factors of OHAVD (all P<0.05). According to the restricted cubic spline models, CVEL of the study subjects in the exposed group had a positive nonlinear dose-response relationship with the risk of OHAVD (overall trend P<0.01, nonlinear P<0.01), indicating an increasing risk of OHAVD with increasing CVEL. Conclusion Hand-transmitted vibration exposure is a risk factor for OHAVD. Early intervention should be carried out for hand-transmitted vibration-exposed individuals to reduce vibration-exposed levels and control vibration exposure time.

Objective To investigate the level of finger systolic blood pressure (FSBP) in healthy young adults. Methods A total of 28 healthy young adults were selected as the study subjects by convenient sampling method. The FSBP of the study subjects was detected at 30 and 10 ℃, and the FSBP index (F_i) was calculated. Results The FSBP of the study subjects at 30 and 10 ℃ were (102.0±16.5) and (104.4±15.2) mmHg, respectively. The FSBP in male group at 30 and 10 ℃ was (99.6±18.6) and (107.2±17.0) mmHg, respectively. The FSBP in female group at 30 and 10 ℃ was (104.4±13.9) and (101.5±2.8) mmHg, respectively. The results of factorial analysis showed that the interaction between gender and temperature on FSBP was statistically significant (P<0.05). FSBP in male group was higher at 10 than 30 ℃ (P<0.05) and higher than female group at 10 ℃ (P<0.05). There was no statistical significance for the main effect of gender, temperature, finger, or the interaction effect of gender and finger, temperature and finger for FSBP (all P>0.05). The average F_i of the study subjects was (98.0±16.6)%, with males and females having the average F_i of (100.7±20.7) % and (95.2±10.6) % respectively. The results of factorial analysis of variance showed that there was no significant difference on F_i in the main effect gender and fingers or the interaction effect between them(all P>0.05). Conclusion The FSBP test could be used as a detection method for assessing peripheral microcirculation function in Chinese population. However, further research is needed to establish reference ranges and influencing factors.

Objective To analyze the current status and influencing factors of occupational stress among medical staff during major public health emergencies. Methods A total of 491 medical staff in Guangzhou City was selected as the research subjects using a convenient sampling method. The Job Content Questionnaire and Effort-Reward Imbalance Questionnaire were used to evaluate the occupational stress level in the job demand-control (JDC) and effort-reward imbalance (ERI) models among the staff. Results Among the research subjects, the detection rates of occupational stress in JDC and ERI models were 50.1% and 52.5%, respectively. There was no significant difference in the detection rates of occupational stress between the two models (P>0.05). The result of multivariate logistic regression analysis showed that individuals with lower monthly income and longer weekly working hours had a higher risk of occupational stress in both JDC and ERI models (all P<0.05). Staff with night shift, daily sleep time less than six hours, and dissatisfaction with the protective measures provided by the hospital had higher risk of occupational stress than those with no night shift, daily sleep time at least six hours, and satisfaction with the protective measures provided by the work place in JDC and ERI models (all P<0.01). The risk of ERI model occupational stress of personnel who had been exposed to COVID-19 cases or suspected cases was higher than that in those who had not been exposed (P<0.05). Conclusion Medical staff experience a certain level of occupational stress, characterized by both JDC and ERI models, during major public health emergencies. The main influencing factors included personal monthly income, weekly working hours, night shift, sleep time, satisfaction with protective measures and occupational exposure.

Background Hand-arm vibration disease is harmful to human body, but there are no effective diagnosis and treatment so far, and current occupational exposure limits underestimate the health damage caused by high-frequency vibration exposure. Objective To evaluate and compare the damage to workers' peripheral circulation and peripheral nerve caused by different frequencies of vibration operation. Methods Drilling workers (n=187) from a mining company in Shandong Province and golf club head grinding workers (n=228) from a sports equipment factory in Guangdong Province were selected as study subjects. Hand symptoms were investigated. SV106 vibration meter was used to measure the target operation-associated vibration frequency spectrum. The 8 h energy-equivalent frequency weighted acceleration, cumulative vibration exposure level (CVEL), and the working age related to causing white finger in 10% of an exposed group were calculated. Result The study subjects were all male. More grinding workers reported hand symptoms than the drilling workers, e.g. peripheral circulation injury (52.6% vs 19.3%), peripheral nerve injury (71.5% vs 23.0%), hand stiffness (64.0% vs 7.0%), and deformed fingers (69.7% vs 4.3%) (all P<0.001). The main vibration frequencies of grinding operation (500-800 Hz) were much higher than those of drilling operation (125~160 Hz). CVEL and working age of vibration exposure showed a linear rising relationship with the cumulative prevalence rate of peripheral circulation and peripheral never injury, the fitting lines all showed good fitting effects (R²=0.812-0.988), and the slope of the fitting line of the grinding workers was larger than that of the drilling workers. The working age of vibration exposure associated with 10% cumulative prevalence of white finger was shorter in the grinding workers than in the drilling workers (6.81 years vs 10.27 years). According to the ISO prediction formula, the working age of vibration exposure was associated with 10% white finger prevalence shorter in the drilling workers than in the grinding workers (3.12 years vs 8.23 years). Conclusion Both the vibration exposure level and the prevalence of hand symptoms are high in two groups of workers with different vibration frequencies, and vibration exposure at a higher frequency tends to have severer damage to workers' hands.

Background Wearing anti-vibration gloves is a simple and effective way to prevent hand-arm vibration disease. The requirements for vibration damping gloves are varied by types of operations exposed to vibration. Objective To study the vibration attenuation and dexterity of different types of protective gloves, and to provide reference for scientific wearing of vibration damping gloves for people working with vibration exposure. Methods Nine kinds of common protective gloves (A and B were dipping gloves; C, D, and E were rubber gloves; F and G were textile and fabric gloves; H was cotton gloves; I was leather gloves) used by workers exposed to vibration in 28 factories in Guangdong Province were selected as research objects by typical case sampling method, and the basic parameters of included protective gloves were investigated and measured. According to ISO 10819:2013, a glove vibration transmissibility (GVT) test system was used to detect the vibration transmissibility values and analyze vibration attenuation characteristics of the subjects wearing different protective gloves. The dexterity was tested by Minnesota Manual Dexterity Test. Pearson test was used to analyze the correlations among glove thickness, vibration transmissibility, dexterity score, and grip strength score. Results For rubber gloves (C, D, and E), the associated average adjusted vibration transmissibility at middle and low frequencies \begin{document}$ {\overline T _{\text{M}}} $\end{document} and average adjusted vibration transmissibility at high frequency \begin{document}$ {\overline T _{\text{H}}} $\end{document} were lower than those of other gloves (0.89-0.91 and 0.59-0.80 respectively), the vibration transmissibility values of 50-200 Hz frequency band was 0.81-0.97, and the vibration transmissibility values of 315-1250 Hz frequency band decreased with the increase of frequency (the minimum value was 0.13). For other types of gloves (A, B, F, G, H, and I), the \begin{document}$ {\overline T _{\text{M}}} $\end{document} and \begin{document}$ {\overline T _{\text{H}}} $\end{document} were 0.95-0.98 and 1.03-1.11 respectively, the vibration transmissibility values of 50-200 Hz frequency band was 0.96-1.02, and the vibration transmissibility values of 400-1250 Hz frequency band increased (the maximum value was 1.29). The \begin{document}$ {\overline T _{\text{M}}} $\end{document}, \begin{document}$ {\overline T _{\text{H}}} $\end{document}, and vibration transmissibility values of 40-1250 Hz frequency band of rubber gloves with double-layer protective materials (C, D, and E) were significantly lower than those of gloves with single-layer protective materials. But the \begin{document}$ {\overline T _{\text{M}}} $\end{document} and \begin{document}$ {\overline T _{\text{H}}} $\end{document} of gloves of other types with double-layer materials (F, H, and I) were still greater than 0.9 and 1.0 respectively. Compared with single-layer protective materials, the gloves of other types with double-layer materials showed no significant changes in the vibration transmissibility values of 25-200 frequency band (0.91-1.06), and an increase in the vibration transmissibility values of 250-630 Hz frequency band (the maximum value was 1.22). The dexterity scores and grip strength scores of dipping gloves (A and B) were the lowest. Rubber gloves C had the highest dexterity score and grip strength score. The thickness of protective gloves was negatively correlated with the vibration transmissibility values, and positively correlated with the dexterity score and the grip strength score (P < 0.05). The vibration transmissibility value was negatively correlated with the dexterity score and the grip strength score (P < 0.05). Conclusion Among the 9 kinds of gloves, cotton gloves and leather gloves have no damping effect. Rubber gloves have certain vibration reduction effect, and the vibration reduction effect on high frequency band is better than that on low frequency band. The thicker the damping material is, the better the damping effect is, but the less the dexterity is. Appropriate damping gloves should be selected according to actual vibration operations.

OBJECTIVE: To investigate the effect of hand-transmitted vibration on the subjective symptoms of mine drilling workers. METHODS: A total of 117 mine drilling workers exposed to hand-transmitted vibration were selected as the exposure group, and 46 workers without hand-transmitted vibration exposure were selected as control group by judgment sampling method. The Occupational Epidemiology Questionnaire of Mine Drilling Workers was used to investigate their subjective symptoms. RESULTS: The prevalence of tinnitus, hearing loss, cough and sputum in the exposure group was higher than that in the control group(P<0.05). The occurrence rate of numbness, tingling, self-reported white fingers and cold hands in the exposure group was higher than that in the control group(P<0.05). The total rate of symptoms of hand in the exposure group was higher than that in the control group(38.5% vs 21.7%, P<0.05). The multivariate logistic regression analysis results indicated that hand-transmitted vibration exposure and service length were risk factors of abnormal hand symptoms(P<0.05). CONCLUSION: Occupational hand-transmitted vibration exposure can affect the hand subjective symptoms of mine drilling workers, and the length of service is a synergistic influencing factor.

OBJECTIVE: To analyze the influence of noise measuring skills by continuous inter-laboratory comparison among occupational hygiene technical service organizations. METHODS: The results of 68, 55 and 50 occupational hygiene technical service organizations(reference organizations) participating in the inter-laboratory comparison of workplace noise measurement in 2014, 2017 and 2018 respectively were collected. The measurement operation and the calculation of equivalent sound level were evaluated according to the GBZ/T 189.8-2007 Measurement of Physical Agents in Workplace--Part 8: Noise.The measured results were analyzed by z score evaluation method. RESULTS: The results of noise measurement field operation of the reference organizations in the year 2014, 2017 and 2018 show that the accuracy rates of instrument setting was 89.7%, 98.2% and 100.0%, the accuracy rates of measuring position were 52.9%, 81.8% and 94.0%, the accuracy rates of sound level meter holding were 54.4%, 80.0% and 92.0%, the accuracy rates of microphone pointing were 98.5%, 98.2% and 94.0%, and the accuracy rates of noise type recognition were 83.8%, 92.7% and 84.0%, respectively. Among them, the accuracy of instrument setting, measurement position and sound level meter holding showed an increasing trend year by year(P<0.01). The pass rates of measurement results were 91.2%, 94.5% and 88.0% in 2014, 2017 and 2018 respectively. The pass rates of equivalent sound level calculation were 73.5%, 92.7% and 88.0%. The pass rates of comprehensive evaluation were 70.6%, 89.1% and 80.0% respectively. Among them, the pass rates of equivalent sound level calculation and comprehensive evaluation in 2017 were higher than that in 2014(P<0.017). There was no significant difference in the three-year comprehensive assessment total pass rate between private organizations and non-private organizations(84.0 % vs 75.5%, P>0.05). There was no significant difference in the total pass rate of three-year comprehensive evaluation between non-Pearl-River-Delta organizations and Pearl-River-Delta organizations(70.3% vs 81.6%, P>0.05). CONCLUSION: Continuous inter-laboratory comparison in occupational hygiene technical service organizations is beneficial to improve on-site noise measure capability.

OBJECTIVE: To analyze the characteristics of noise hazard in a nuclear power station. METHODS: The workplaces and working posts which exposed to occupational noise from two 1 000 MW power units in one nuclear power station in Guangdong Province was selected as study subjects using the convenience sampling method. Occupational health survey, noise measurement in the workplace and personal noise dosage measurement were used to monitor noise exposure, and to analyze the characteristics of occupational noise in the nuclear power station. RESULTS: The noise sources of the nuclear power plant were mainly distributed in the nuclear island, conventional island, and peripheral workshops. A total of 237 points of noise intensity were measured in the workplace. The intensity of noise ranged from 66.0 to 99.6 dB(A). The noise intensity in 62.4%(148/237) of points was equal or greater than 80.0 dB(A) and 34.2%(81/237) equal or greater than 85.0 dB(A). The percentage of detection points with noise intensity was equal or greater than 85.0 dB(A) from low to high were nuclear island, conventional island, and peripheral workshops with 22.0%, 37.5% and 53.8% respectively(P<0.01). The personal noise intensity of three positions including inspectors of operation department, preparation and main engine positions of mechanical department exceeded the occupational exposure limit(OEL), and the percentage of positions whose noise intensity exceeded the OEL was 9.7%(3/31). CONCLUSION: High-intensity noise sources of the nuclear power plant are widely distributed in the workshop areas of nuclear island, conventional island, and peripheral workshops. The noise level of some positions exceeded the standards of noise intensity. The prevention and control measures of noise hazards in posts with excessive noise should be strengthened.