Objective To obtain the data of radiological diagnosis and treatment resource distribution at medical institutions of different levels and in various cities, understand the status of resource allocation, provide policy-making basis and suggestions for optimizing the allocation of radiological diagnosis and treatment resources within the province, and offer data and references for related research. Methods A basic situation questionnaire survey was conducted on radiological diagnosis and treatment institutions in Hunan Province. Data were reviewed, analyzed, and statistically processed using Excel software to understand the allocation situation of radiological diagnosis and treatment resources in Hunan Province. Results As of 2022, there were 3031 radiological diagnosis and treatment institutions, 19770 radiation workers, and 6617 pieces of radiological diagnostic and treatment equipment. There were 80 radiation treatment institutions, 49 nuclear medicine institutions, 178 interventional radiology institutions, and 3028 X-ray imaging diagnosis institutions. There were 1077 radiation workers in radiation treatment, 461 radiation workers in nuclear medicine, 3369 radiation workers in interventional radiology, and 14,863 radiation workers in X-ray imaging diagnosis. There were 135 pieces of radiation treatment equipment, 56 pieces of nuclear medicine equipment, 262 pieces of interventional radiology equipment, and 6164 pieces of X-ray imaging diagnosis equipment. Conclusion Primary and lower grade medical institutions in Hunan Province account for a relatively high proportion of the total number of medical institutions, whereas radiological diagnostic and treatment resources are predominantly concentrated in tertiary medical institutions, demonstrating a unbalanced allocation of radiological diagnosis and treatment resources in various cities. In terms of the overall allocation of radiological diagnosis and treatment resources, interventional radiology is superior to the national average, nuclear medicine and X-ray imaging diagnosis are comparable to the national averages, and radiation treatment is lower than the national average. The total GDP is not the decisive factor in determining the development of local medical levels. It is suggested that relevant authorities should improve the rationality of the planning for the allocation of radiological diagnosis and treatment resources, promote the allocation of radiological diagnosis and treatment resources to the grassroots and underdeveloped areas through various measures, and thus achieve the goal of balanced resource allocation.

Background With the unprecedented development of aviation business, the work load and job burnout of airport employees are becoming more and more serious, and the impact on sleep quality needs to be addressed. Objective To explore the current situation of work load and sleep quality of airport employees, and whether job burnout plays a role in the relationship between the two variables. Methods During September 2023, a cross-sectional survey was conducted among employees of an airport in Hunan Province, and 1503 employees were surveyed. A basic information questionnaire, a work load measurement questionnaire, Maslach Burnout Inventory General Survey, and Pittsburgh Sleep Quality Index were used in the survey. Logistic regression was used to analyze the influencing factors of sleep quality. SPSS 25.0 PROCESS v4.1 plug-in was used to analyze the mediating effect of job burnout. Results A total of 1503 questionnaires were distributed in this study, and 1424 valid questionnaires were recovered, with a recovery rate of 94.7%. The rate of heavy work load was 50.0% (712/1424), the rate of job burnout was 74.6% (1062/1424), and the rate of sleep disorders was 58.7% (836/1424). The results of logistic regression analysis showed that individuals with job burnout had a 1.734 times higher risk of reporting sleep disorders compared to those without job burnout (95% CI: 1.306, 2.302); compared to those with light work load, individuals with heavy work load have a higher risk of sleep disorders (OR=3.422, 95%CI: 2.639, 4.437). The results of mediating effect test indicated a work load-burnout-sleep quality pathway (P <0.001), with a mediation effect value of 0.1052 (95%CI: 0.019, 0.067), accounting for 18.02% of the total effect. Conclusion The rate of job burnout and the rate of reporting poor sleep quality are high among airport employees, and job burnout plays a mediating role in the relationship between work load and sleep quality. Adopting measures to reduce work load and reduce burnout can improve the sleep quality of airport employees.

Objective To establish a method for the determination of mercury, methylmercury (MeHg) and ethylmercury (EtHg) in the hair of mercury-exposed individuals using high performance liquid chromatography-atomic fluorescence spectrometry. Methods About 0.20 g of hair was mixed with 5.0 mL of hydrochloric acid to a concentration of 5.00 mol/L. After standing for 12 hours, ultrasonic extraction was carried out for 30 minutes at room temperature. Ammonia solution was added dropwise into 2.0 mL supernatant after centrifuge to adjust the pH to 4-5. The solution was diluted to 10.0 mL with pure water after mixed with 0.2 mL of L-cysteine with a mass concentration of 10.0 g/L. The mobile phase consisted of 5.0% methanol + a mass concentration of 0.06 mol/L ammonium acetate + a 0.1% L-cysteine, and was used for separation by a C₁₈ liquid chromatography column, followed by detection using atomic fluorescence spectrometry after UV digestion. Results The linear relationship of mercury, MeHg and EtHg in human hair was good at mass concentrations of 0.0-10.0 μg/L, with all correlation coefficients >0.999 0. The detection limit of mercury, MeHg and EtHg was 0.008, 0.008, and 0.010 μg/g, respectively. The within- and between- run relative standard deviations of the three forms of mercury were 1.6%-4.3% and 2.0%-5.6%, respectively, and the recovery rates were 94.0%-101.2%. Conclusion This method is simple, with low detection limit, high sensitivity, and good accuracy, and is suitable for the simultaneous determination of mercury, MeHg and EtHg in the hair of mercury-exposed individuals.

Background The complex and diverse occupational disease hazards in automobile manufacturing industry pose high occupational health risks to workers. Objective To explore the methods that can accurately reflect the workplace health risk grade of automobile manufacturing enterprises, and to guide enterprises to practice risk classification management. Methods Comprehensive index method, International Commission on Mining and Metals occupational health risk assessment method (ICMM method), and risk index method were used toassess health risks of occupational disease hazards in major workstations such as welding, polishing, and painting in three automobile manufacturing enterprises in Hunan Province. Kappa consistency test was used to test the grading results of the three assessment methods. The re-examine results and detection rate of contraindications of occupational health examinations in the past three years were used to verify the assessment results. Results The results of comprehensive index method showed that the hazards of each selected workstation in enterprises A and B were evaluated as grade 2-3, among which NO₂ in enterprise A was grade 3, and welding fume, NO₂, and formaldehyde in enterprise B were all grade 3. The hazards of each selected workstation in enterprise C were grade 3-4, among which NO₂ and benzene in were grade 4, and welding fume, manganese and its compounds, grinding wheel dust, and xylene were grade 3. The hazards evaluated by ICMM quantitative method were grade 2 and grade 5, among which manganese and its compounds in enterprise A and welding fume, grinding wheel dust, and benzene series in enterprise C were graded as grade 5. The hazards evaluated by risk index method were grade 1-4, among which manganese and its compounds in enterprises A and B were grade 3, and manganese and its compounds and benzene in enterprise C were grade 4. The Kappa value between comprehensive index method and ICMM method was 0.084 (P>0.05), that between comprehensive index method and risk index method was −0.046 (P>0.05), and that between ICMM method and risk index method was 0.014 (P>0.05), indicating poor consistency. By comparing the results of occupational health surveillance with the results of occupational health risk assessment, one worker was found to have occupational contraindication of manganese exposure and 1 worker was found to have excessive manganese in hair in enterprise A. However, the comprehensive index method graded low risk for manganese and its compounds in enterprise A and the result is conservative. The key workstations identified by ICMM method were consistent with the occupational health examination results, but the assessment grades were all extremely high risk, and the results were too strict. One worker was found to be contraindicated to welding fumes, and 2 polishers were found to have severe mixed pulmonary ventilation dysfunction in enterprise C. Mild and moderate pulmonary ventilation dysfunction was found to be common in welding and polishing workstations in each enterprise. The assessment results of welding fumes and grinding wheel dust by the risk index method were negligible risks, which were inconsistent with the occupational health examination results. Conclusion The comprehensive index method, ICMM method, and risk index method can basically identify workstations with serious occupational hazards, but they have certain limitations and applicability. In general, the evaluation results of the comprehensive index method were generates more consistent with the results with occupational health surveillance than the other two methods, is more comprehensive and objective in consideration, and is more suitable for health risk assessment of automobile manufacturing enterprises.

Background The mining of non-coal underground mines may come into contact with various types of dust, such as lead, zinc, copper, and non-metallic minerals. Dust of various kinds commonly exists in all aspects of mining and selection, and is one of the main occupational hazard groups in non-coal underground mines. Objective To compare the application of two risk assessment methods in the occupational health risk assessment of productive dust in non-coal underground mines, and to provide a reference for the selection of dust hazard health risk assessment methods and the management of dust hazards in non-coal mines. Methods A field investigation of the dust hazards of three typical non-coal underground mining enterprises (lead-zinc mines, copper mines, and fluorite mines) was carried out, and the comprehensive index method and the occupational health risk assessment method from the International Council on Mining and Metals (ICMM) were used to perform risk assessments. The comprehensiveindex method considers the following factors: dust monitoring data, the aerodynamic diameter of dust, hazard control measures, occupational health management, daily usage, and daily exposure time to determine exposure levels. The ICMM method determines the risk level based on the consequences caused by dust, exposure probability, exposure time, and uncertainty coefficient. Kendall consistency test was used to compare agreement between the results generated by the two methods. Results The results generated by the comprehensive index method were as follows: level 3 (medium risk) or level 4 (high risk) for silica dust or lead dust; level 1 (negligible risk) or level 2 (low risk) for other dust (dust with free SiO₂ content<10% and containing lead, zinc, and copper, using other dust limit values for comparison), fluorspar mixed dust, fluorine and its compounds, zinc oxide, and copper dust. The risk levels graded by the ICMM method were as follows: level 4 (very high risk) and level 3 (high risk) for exposure to silica dust and lead dust, respectively, and level 1 (tolerable risk) or level 2 (potential risk) for exposure to other dust (dust with free SiO₂ content <10% and containing lead, zinc, and copper, using other dust limit values for comparison), fluorspar mixed dust, fluorine and its compounds, zinc oxide, and copper dust. The consistency level between the results graded by the two methods was very high (Kendall W coefficient=0.974, P < 0.05). Conclusion For the occupational health risk assessment of productive dust in non-coal underground mines, the consistency level of risk assessment results between the ICMM method and the comprehensive index method is very high. The ICMM method is more convenient to operate and should be preferred in assessing health risks of dust hazard in non-coal underground mines.

The direct negative impact of the transcriptional activity of one component on the second one in c/s is referred to as transcriptional interference (TI).U6 is a type Ⅲ RNA polymerase Ⅲ promoter commonly used for driving small hairpin RNA (shRNA) expression in vector-based RNAi.In the design and construction of viral vectors,multiple transcription units may be arranged in close proximity in a space-limited vector.Determining if U6 promoter activity can be affected by TI is critical for the expression of target shRNA in gene therapy or loss-of-function studies.In this research,we designed and implemented a modified retroviral system where shRNA and exogenous gene expressions were driven by two independent transcriptional units.We arranged U6 promoter driving.shRNA expression and UbiC promoter in two promoter arrangements.In primary macrophages,we found U6 promoter activity was inhibited by UbiC promoter when in the divergent arrangement but not in tandem.In contrast,PKG promoter had no such negative impact.Instead of enhancing U6 promoter activity,CMV enhancer had significant negative impact on U6 promoter activity in the presence of UbiC promoter.Our results indicate that U6 promoter activity can be affected by TI in a proximal promoter-specific and arrangement-dependent manner.

The efficient,stable delivery of siRNA into cells,and the appropriate controls for non-specific off-target effects of siRNA are major limitations to functional studies using siRNA technology.To overcome these drawbacks,we have developed a single lentiviral vector that can concurrently deplete endogenous gene expression while expressing an epitope-tagged siRNA-resistant target gene in the same cell.To demonstrate the functional utility of this system,we performed RNAi-depleted α-actinin-1 (α-ACTN1) expression in human T cells,α-ACTN1 RNAi resulted in inhibited chemotaxis to SDF-1α,but it can be completely rescued by concurrent expression of RNAi-resistant α-ACTN1 (rr-α-ACTN1) in the same cell.The presence of a GFP tag on rr-α-ACTN1 allowed for detection of appropriate subcellular localization of rr-α-ACTN1.This system provides not only an internal control for RNAi off-target effects,but also the potential tool for rapid structure-function analyses and gene therapy.