Objective To investigate the annual effective doses to radiation workers caused by radon concentrations in the underground workplaces of medical institutions, and to provide a scientific basis for the prevention and control of indoor radon in underground places. Methods A typical sampling method was used to select 5-30 medical institutions in each of Hunan, Jiangxi, Guizhou, Hubei, and Sichuan provinces. A total of 66 monitoring points in 66 medical institutions were selected. The indoor radon concentrations in underground workplaces were measured cumulatively using CR-39 solid nuclear track detectors. The radiation dose to radiation workers was estimated according to the method outlined in the Requirements for control of indoor radon and its progeny (GB/T 16146—2015). The Kruskal-Wallis H test was used to compare the differences in indoor radon concentrations between different provinces. Results The average indoor radon concentration in the underground workplaces of 66 medical institutions was 69.8 Bq/m³, with the highest being 147.6 Bq/m³. The average indoor radon concentrations in the underground workplaces of medical institutions in Sichuan, Guizhou, Hubei, Jiangxi, and Hunan were 72.1, 83.2, 66.6, 88.4, and 61.5 Bq/m³, respectively. The annual effective doses to radiation workers caused by radon concentrations in underground workplaces were 0.57-0.83 mSv, with an average of 0.69 mSv. There was a significant difference in radon concentrations among provinces (P < 0.05). Conclusion The indoor radon concentrations and personnel exposure doses in the underground workplaces of monitored medical institutions comply with national control standards. However, continuous monitoring and necessary indoor radon prevention and control measures are still needed.

Objective To evaluate the current status in the implementation of GBZ/T 201.5-2015 Radiation shielding requirements for radiotherapy rooms-Part 5: Radiotherapy room of proton accelerators, identify issues in the application of its technical indicators, and provide a basis for the in-depth implementation and further revision of the standard. Methods In accordance with the Standardization Law of the People’s Republic of China and the Guidelines for Health Standards Tracking Evaluation (WS/T 536-2017), a combination of cluster sampling and stratified sampling methods was employed to select professionals involved in proton accelerator radiotherapy devices and facilities in three provinces (or municipalities directly under the central government) as the subjects of the survey. A questionnaire was developed to collect basic information about the subjects and their understanding and application of the technical indicators in the standard. A standard evaluation indicator system with a total score of 100 points was established to score the implementation of the standard (40 points), the technical content (30 points), and the effectiveness of the implementation (30 points). Results A total of 169 professionals from 107 institutions participated in the survey, with 79.88% of the respondents having at least 5 years of experience in radiation therapy and 74.56% holding intermediate or higher professional titles. The score of standard implementation was 18.3 points. The awareness rate exceeded 80%, indicating a high level of awareness about the standard. However, the scores for the dissemination and application of the standard were relatively low, accounting for 28% and 32% of their respective full marks. The technical content of the standard and the effectiveness of its implementation scored 27.0 and 26.6 points, respectively. The overall score in the evaluation of standard implementation was 72 points, with scores of 68.6, 72.3, and 75.0 for Beijing City, Shanghai City, and Jiangsu Province, respectively. Conclusion GBZ/T 201.5-2015 Radiation shielding requirements for radiotherapy rooms-Part 5: Radiotherapy room of proton accelerators is scientific and operable, and it is well-coordinated with relevant laws and standards. However, considering the development in FLASH technology and multi-chamber radiotherapy room, it is necessary to revise and improve the standard.

Objective To investigate the levels of radionuclides in food in Beijing, China, and assess the committed effective dose to local residents from food intake. Methods From 2021 to 2022, a total of 65 food samples across 7 categories were collected in Beijing. The activity concentrations of radionuclides, including ¹³⁷Cs, ²¹⁰Pb, ²³⁸U, ²²⁸Ra, ²²⁶Ra, ⁴⁰K, ⁹⁰Sr, ²¹⁰Po, ³H and ¹⁴C, were measured using gamma spectrometry and radiochemical methods. By combining the monitoring results with dietary consumption data of Beijing residents and the internal dose coefficients for Chinese reference adult phantom, the committed effective dose was estimated. Results The levels of radionuclides in food in Beijing were within the normal background range, consistent with related surveys in China and abroad, with activity concentrations below national standard limits. No significant differences were found in the activity concentrations of ¹³⁷Cs, ²³⁸U, ²²⁸Ra, ²²⁶Ra and ⁴⁰K between food samples collected from key areas and those from control areas (P > 0.05). The committed effective doses calculated according to internal dose coefficients for Chinese reference adult male phantom and GB 18871-2002 were 0.26 mSv and 0.19 mSv, respectively. Based on the Chinese reference adult male phantom, the majority of the committed effective dose was attributed to ²¹⁰Pb (45.1%), ²²⁸Ra (37.1%), ²¹⁰Po (12.3%), and ²²⁶Ra (4.7%). Conclusion The levels of radionuclides in food in Beijing fluctuated within the background range, resulting in a low radiation dose burden to the population.

Objective:To formulate refined management strategies to improve the operation quality and protective effect of medical X-ray diagnosis equipment based on the risk analysis of the correlation of medical X-ray diagnostic equipment.Methods:The used 41 medical X-ray diagnosis equipment in Fuwai Hospital,Chinese Academy of Medical Sciences from January 2022 to December 2023 were selected.According to different management modes for equipment,they were managed respectively by the conventional management mode(20 units)and the management mode with risk analysis of the correlation(21 units).The risk grades of correlation of management mode with risk analysis of the correlation were classified on the basis of the probability of risk and the degree of harm in medical X-ray diagnosis equipment.The protection management of equipment was conducted from three aspects included the location of equipment,the staffs and subjects.A self-made questionnaire was used to investigate the satisfactions of engineers of using management for equipment,operators,and staffs of operating and maintaining equipment for the two kinds of management modes.The protection quality,failure rate of equipment,and qualification rate of protection of medical X-ray diagnosis equipment under different management modes were compared.Results:The quality scores of operation safety,regular inspection,maintenance and repair,and shielding protection for radiation of medical X-ray diagnosis equipment that adopted the management mode with risk analysis of the correlation were respectively(92.14±3.36),(91.47±2.41),(92.54±3.32)and(91.69±3.57)points,all of which were higher than those of the conventional management mode,and the differences of them were statistically significant(t=16.396,17.368,19.688,14.401,P<0.05).The failure rate of the 21 medical X-ray diagnosis equipment that adopted the management mode with risk analysis of correlation was 0,which was lower than 20.00%of the conventional management mode.The qualified rate of protection was 95.23%,which was higher than 70.00%of the conventional management mode,and the differences of them were statistically significant(x2=4.654,4.608,P<0.05).The satisfaction scores of engineers of using equipment,operators and staffs of operating and maintaining equipment for the protective effect of adopting the management mode with risk analysis of correlation were respectively(94.69±4.02),(93.21±4.36)and(92.54±3.47)points,all of which were higher than those of the conventional management mode,and the differences were statistically significant(t=16.902,11.291,12.020,P<0.05).Conclusion:The process-based protection management strategy on the basis of risk analysis of correlation for medical X-ray diagnosis equipment can prevent risks of medical X-ray diagnostic equipment,and improve the operation quality of the equipment,and reduce the operation risks of the equipment,and maximize the enhancement for management quality of medical X-ray diagnosis equipment.

Objective:To formulate refined management strategies to improve the operation quality and protective effect of medical X-ray diagnosis equipment based on the risk analysis of the correlation of medical X-ray diagnostic equipment.Methods:The used 41 medical X-ray diagnosis equipment in Fuwai Hospital,Chinese Academy of Medical Sciences from January 2022 to December 2023 were selected.According to different management modes for equipment,they were managed respectively by the conventional management mode(20 units)and the management mode with risk analysis of the correlation(21 units).The risk grades of correlation of management mode with risk analysis of the correlation were classified on the basis of the probability of risk and the degree of harm in medical X-ray diagnosis equipment.The protection management of equipment was conducted from three aspects included the location of equipment,the staffs and subjects.A self-made questionnaire was used to investigate the satisfactions of engineers of using management for equipment,operators,and staffs of operating and maintaining equipment for the two kinds of management modes.The protection quality,failure rate of equipment,and qualification rate of protection of medical X-ray diagnosis equipment under different management modes were compared.Results:The quality scores of operation safety,regular inspection,maintenance and repair,and shielding protection for radiation of medical X-ray diagnosis equipment that adopted the management mode with risk analysis of the correlation were respectively(92.14±3.36),(91.47±2.41),(92.54±3.32)and(91.69±3.57)points,all of which were higher than those of the conventional management mode,and the differences of them were statistically significant(t=16.396,17.368,19.688,14.401,P<0.05).The failure rate of the 21 medical X-ray diagnosis equipment that adopted the management mode with risk analysis of correlation was 0,which was lower than 20.00%of the conventional management mode.The qualified rate of protection was 95.23%,which was higher than 70.00%of the conventional management mode,and the differences of them were statistically significant(x2=4.654,4.608,P<0.05).The satisfaction scores of engineers of using equipment,operators and staffs of operating and maintaining equipment for the protective effect of adopting the management mode with risk analysis of correlation were respectively(94.69±4.02),(93.21±4.36)and(92.54±3.47)points,all of which were higher than those of the conventional management mode,and the differences were statistically significant(t=16.902,11.291,12.020,P<0.05).Conclusion:The process-based protection management strategy on the basis of risk analysis of correlation for medical X-ray diagnosis equipment can prevent risks of medical X-ray diagnostic equipment,and improve the operation quality of the equipment,and reduce the operation risks of the equipment,and maximize the enhancement for management quality of medical X-ray diagnosis equipment.

Objective To explore the uranium concentration in surface water and drinking water in Beijing, China and the relationship between uranium concentration and gross α activity concentration. Methods Water samples were collected from 16 districts in Beijing. Uranium concentration and gross α activity concentration were measured with WGJ-III trace uranium analyzer and LB6008 six-channel α/β counter using the ultraviolet fluorescence and thick source methods. Results The uranium concentrations in surface water and drinking water were 1.131 and 1.572 μg/L, respectively. The gross α activity concentrations in surface water and drinking water were 0.059 and 0.074 Bq/L, respectively. There were no significant differences in uranium concentration and gross α activity concentration between surface water and drinking water (P > 0.05). The uranium concentration was positively correlated with the gross α activity concentration, with a correlation coefficient of 0.700 (P < 0.05). The gross α activity concentration was determined by the uranium concentration with a determination coefficient of 48%. The committed effective dose of ²³⁸U in drinking water was between 3.284 × 10⁻⁵ and 1.640 × 10⁻³ mSv, with an average value of 5.400 × 10⁻⁴ mSv. Conclusion The uranium concentration and gross α activity in the surface water and drinking water in Beijing fluctuate and remain in the background range. These values are much lower than the recommended limits of 0.03 mg/L and 0.5 Bq/L stipulated in the GB 5749-2021 Standard for Drinking Water Quality. The annual committed effective dose of ²³⁸U through drinking water ingestion is very small.

Objective To investigate the method of tube furnace oxidation combustion and liquid scintillation counting for the determination of carbon-14 in seafood, and to provide technical support for the monitoring of carbon-14 in seafood. Methods By studying the pyrolysis characteristics of five types of dried seafood samples, including yellow croaker, white shrimp, swimming crab, clam, and seaweed, a temperature control program suitable for the oxidation combustion of seafood was established. The combustion efficiency, carbon element recovery rate, and the accuracy and precision of the method were determined. Results The combustion efficiency was more than 98% for most seafood using the recommended combustion program. The recovery rate of carbon was similar to that calculated by glucose combustion; both were more than 95%. Four laboratories validated the accuracy of the method by measuring the carbon-14 activity concentration in the Chinese sugar carbon standard material. The relative errors ranged from 1.03% to 3.41% and the average relative error was 2.36%. The precision of this method was verified by measuring the carbon-14 activity concentration in yellow croaker samples. The within-laboratory relative standard deviation ranged from 5.11% to 9.35% and the between-laboratories relative standard deviation was 4.04%. Conclusion The tube furnace oxidation combustion and liquid scintillation counting method was used to determine the activity concentration of carbon-14 in seafood. The recommended oxidation combustion program is more targeted and less time-consuming. The accuracy and precision of this method meet the requirements. This method is suitable for the determination of carbon-14 in seafood.

Objective To understand the effects of ²⁴¹Am standard material powder with different matrices on the determination of gross alpha activity in water, and to provide a reference for the selection and use of alpha standard sources. Methods The alpha counting efficiency of ²⁴¹Am standard material powder with different matrices was measured by low-background alpha and beta measuring instrument. The radiochemical recovery rate and whole process efficiency of gross alpha activity in water were determined by spike experiments. Results The alpha counting efficiency of the ²⁴¹Am standard material powder with four matrices was in the descending order of calcium carbonate, calcium carbonate and silica mixed matrix, calcium sulfate, and silica. The default chemical recovery rate is 1 when gross alpha activity in water is measured by thick source method. The use of ²⁴¹Am standard material with calcium carbonate as a matrix resulted in about 35% decrease in gross alpha activity, and about 10% deviation was observed using ²⁴¹Am standard material with silica or calcium carbonate and silica mixed matrices. The whole process efficiency of alpha activity in four spiked water samples with ²⁴¹Am standard solution and ²⁴¹Am standard material powder with calcium carbonate, silica, or mixed matrix was 6.34%-7.30%. Conclusion Standard materials with different matrices demonstrate different self-absorption of alpha particles and various influence on the chemical recovery. When purchasing and using standard material powders for alpha activity measurement in laboratories, the composition of the matrix should be clarified as much as possible, and the gross alpha activity in water should be determined by measuring the whole process efficiency if necessary.

Objective To analyze the clinical characteristics and survival prognosis of patients with AIDS-related malignant tumor. Methods We retrospectively analyzed the data of 354 patients with AIDS-related malignant tumor. Univariate analysis was conducted by Log rank test and multivariate analysis was conducted by Cox proportional risk regression model. Results The average age of the patients was 54.10±12.96 years old. The ratio of male to female patients was 2.1:1. The number of patients with AIDS complicated with lymphoma was the most, accounting for 28.25%. The 1-, 3- and 5-year survival rates were 78.48%, 62.13% and 55.31%, respectively. Univariate analysis showed that there were statistical differences in prognosis of patients with different types of malignant tumor, age, gender, medical insurance type, number of admissions after diagnosis of AIDS, average length of stay, radiotherapy or not, leaving hospital according to medical advice. Multivariate analysis showed that gender, number of admissions after diagnosis of AIDS, average length of stay, proportion of out-of-pocket and leaving hospital according to medical advice were independent risk factors affecting the survival and prognosis of patients. Conclusion AIDS is easily complicated with lymphoma, lung cancer and cervical cancer. The patients received insufficient anti-tumor courses in hospital.

Objective:To explore the relationships between serum lipids, CA153 level and breast cancer incidence and clinicopathological features of patients.Methods:A total of 198 patients with breast cancer diagnosed and treated at Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School were enrolled as the case group, and 198 healthy women were selected with 1∶1 age pairing as controls. Five milliliters of fasting venous blood was collected to measure serum lipids levels in all subjects and CA153 levels in breast cancer patients. The difference of serum lipids levels between the two groups was compared. Logistic regression model was used to analyze the risk factors of breast cancer. For 165 breast cancer patients who did not receive neoadjuvant chemotherapy, independent sample t-test was used to compare serum lipids and CA153 levels in breast cancer patients with different pathological features, and Pearson correlation analysis was used to calculate the correlation between variables and CA153. Results:The triglyceride (TG) levels in the case group and the control group were (1.22±0.73) mmol/L and (1.06±0.52) mmol/L respectively, and the difference was statistically significant ( t=2.559, P=0.011); the total cholesterol (TC) levels were (4.47±0.86) mmol/L and (4.99±0.80) mmol/L respectively, and the difference was statistically significant ( t=-6.228, P<0.001); the high-density lipoprotein cholesterol (HDL-C) levels were (1.32±0.34) mmol/L and (1.53±0.38) mmol/L respectively, and the difference was statistically significant ( t=-5.913, P<0.001). Higher TC and HDL-C levels were independent protective factors for breast cancer ( OR=0.350, P<0.001; OR=0.531, P=0.013). The TC levels in lymph node positive and lymph node negative patients were (4.36±0.73) mmol/L and (4.67±0.83) mmol/L respectively, and the difference was statistically significant ( t=-2.518, P=0.013); low-density lipoprotein cholesterol (LDL-C) levels were (2.53±0.58) mmol/L and (2.77±0.70) mmol/L respectively, and the difference was statistically significant ( t=-2.312, P=0.022). The TC levels in patients with stage Ⅰ and stage Ⅱ/Ⅲ were (4.90±0.89) mmol/L and (4.46±0.76) mmol/L respectively, and the difference was statistically significant ( t=2.855, P=0.005); LDL-C levels were (2.95±0.71) mmol/L and (2.60±0.63) mmol/L respectively, and the difference was statistically significant ( t=2.705, P=0.008). The level of CA153 in triple-negative breast cancer patients [(14.94±7.45) U/ml] was significantly higher than that in non-triple-negative breast cancer patients [(11.96±5.96) U/ml], and the difference was statistically significant ( t=2.359, P=0.020). The level of CA153 was positively correlated with the level of TG ( r=0.167, P=0.032). Conclusion:Dyslipidemia is associated with an increased risk of breast cancer. The levels of serum lipids vary among patients with different lymph node status and tumor stages. CA153 level is positively correlated with TG level to some extent.