Objective:To investigate the indoor radon concentrations and to analyze their seasonal variations in urban and rural residential dwellings in Ningxia province.Methods:From March 2022 to March 2023, based on the administrative region division and population distribution in Ningxia, a total of 143 typical residential dwellings, including 82 urban houses and 61 rural houses, were selected to measure indoor radon concentration by CR-39 solid nuclear track detectors for 1 year in Ningxia, with detectors changed every 3 months.Results:The annual average indoor radon concentration in Ningxia was 88 Bq/m 3, range 39-226 Bq/m 3. The annual average indoor radon concentration was below 100 Bq/m 3 for 69.9% of the measured dwellings, and below 300 Bq/m 3 for all of surveyed dwellings. Indoor radon concentrations in rural areas were much higher than those in urban areas ( Z=5.85, P<0.05). Indoor radon concentration varied significantly with the seasons, higher in autumn and winter, but lower in spring and summer, in total ( χ2=63.97, P<0.05), urban ( χ2=24.74, P<0.05), and rural ( χ2=43.15, P<0.05). Conclusion:The annual average indoor radon concentrations in all the measured dwellings are below the reference level of 300 Bq/m 3 recommended by Indoor Air Quality Standard (GB/T 18883-2022) in China.

Objective:To conduct radiation detection and dose assessment in selective internal radiotherapy with 90Y resin microspheres for the purpose of providing a reference for radiological protection. Methods:The dose rates from radiotherapy with 90Y resin microspheres were detected in the process of each operation at different distances from the body surface of patients the levels of dose to the persons concerned were compared with the relevant national regulations and standards. Results:The estimated dose rates were 1.12-454 μSv/h during 90Y resin microspheres dispensing and 2.06-58.2 μSv/h during surgical procedure. The dose rates at 0.5 h after surgery were 22.7-64.1 μSv/h at 5 cm and 0.82-2.55 μSv/h at 1 m from three patient′s body surface. Assuming treating 200 patients a year, the annual individual effective dose to the radiation workers was 0.12-1.03 mSv/year. The annual individual effective dose to the public, comforters and carers of patients was 0.02-0.24 mSv/year after release of a patient. Conclusions:During the treatment, nursing and release of patients, the radiation doses to workers, carers and the public are lower than the individual dose limit given in the GB18871-2002 basic standards for protection against ionizing radiation and for the safety of radiation sources and the management target value set by of the relevant medical institutions.

Objective:To evaluate 90Y activity concentration in renal excretions during the first 48 hours after being treated with 90Y resin microspheres seleceive internal radiation therapy(SIRI) and to provide advice on the management of patient excreta after surgery. Methods:After surgery, urine excreted from 3 patients during 0-24 h and 24-48 h was collected respectively, and the 90Y activity concentration in urine was tested and analyzed. Results:90Y radioctivity in the urine excreted from 3 patients after surgery was (1 266±258)kBq/GBq during 0-24 h and (140±106) kBq/GBq during 24-48 h, respectively, and 90Y activity concentration were (640±113) kBq/L during 0-24 h and (53±12) kBq/L during 24-48 h. Conclusions:90Y radioactivity in patient′s urine excreted at 1 d was about 10 times higher than that at 2 d. After surgery, patients can accelerate the reduction of free 90Y activity by increasing excretion. Urine excreted by the patients during hospitalization should be handled in accordance with the requirements of the national standard HJ 1188-2021 Radiation protection and safety requirements for nuclear medicine.

Objective To compare the results of accumulation and continuation methods in indoor radon measurement. Methods The radon concentrations in 30 households in 7 provincial capital cities of China were simultaneously measured using both accumulation and continuation methods. Results The radon concentration measured by accumulation method in 30 households ranged from 21 to 323 Bq/m³, with a median M(P₂₅, P₇₅) of 70.5 (43.8, 111). The radon concentration measured by the continuation method ranged from 16.1 to 258 Bq/m³, with a median M(P₂₅, P₇₅) of 100 (51.3, 141). The average relative percent deviation between the two measurement methods was 41.8%. There were significant differences among the measurement results at 8, 16, and 24 h by the continuation method. Pairwise comparisons showed there were statistical diffferences between 8 h and 16 h, as well as between 8 h and 24h; however, no statistical significance was found (P < 0.05), between 16 h and 24 h. Conclusion The overall continuous measurement results of the 30 households were higher than those of cumulation method. The comparison between accumulation and continuation measurement results did not show a high level of correlation (r=0.49). The continuation method is significantly affected by environmental factors, and the length of the measurement period can affect the measurement results. The selection of indoor radon measurement methods should consider the purpose, sample size, and environmental conditions.

Objective To investigate the suitable methods for reducing the concentration levels of residential radon and its daughters. Methods Three rooms were selected and treated by natural ventilation, air purifier, and sealing/shielding, respectively. The EQF3120 device was used to measure the concentrations of radon and its daughters, and the alpha nuclear trail detector was used to measure indoor radon concentration. The three methods were compared in terms of radon reduction effect. Results After natural ventilation for 2-10 hours, the average reduction rates of the concentrations of radon and attached and unattached radon daughters in the room were 87.7%, 89.8%, and 93.7%, respectively; in the room with air purifier, the concentrations of radon and attached and unattached radon daughters were reduced by 46.3%, 94.5%, and 45.3%, respectively; after sealing and shielding, the concentration of radon was reduced by 74.9% after 1 month and 59.2% after 1 year. Conclusion All three methods have a marked effectin reducing the concentrations of indoor radon and its daughters, and natural ventilation is the most economical and effective method for reducing radon.

Objective:To investigate basic characteristics of diabetes prevalence and associated factors in centenarians in Hainan province of China.Methods:All the subjects were from China Hainan Centenarian Cohort Study. A total of 1 002 centenarians were included in the final analysis, who were divided into three groups: diabetes group, impaired fasting glucose (IFG) group, and normal glucose group according to the guideline.Results:The average age of centenarians was (102.77±2.55) years, and the proportion of females was 82.0%. There were 95 centenarians who suffered from diabetes, and the prevalence rate was 9.5%. There were 81 centenarians who had IFG, and the prevalence rate was 8.1%. The mean fasting plasma glucose (FPG) level of centenarians was (5.12±1.44) mmol/L, while 43.5% of centenarians had FPG levels ranging from 4.00 to 5.00 mmol/L and 22.1% of centenarians had the FPG levels ranging from 5.00 to 6.00 mmol/L. Increased triglyceride level and abdominal obesity might be associated with the risk for diabetes.Conclusion:The glycometabolism in centenarians in Hainan was better than that in other age groups, and no gender specific difference was observed.

Objective:To explore the blood pressure levels and the influencing factors of hypertension among Hainan centenarians, and provide basic data for the further blood pressure related studies of the centenarian population.Methods:The baseline data were from China Hainan Centenarian Cohort Study (CHCCS). This cross-sectional data, based on the community population, was a complete sample study of centenarians, including questionnaire survey, physical examination and physiological index detection. A total of 1 002 centenarians were recruited to describe the blood pressure level. According to the guidelines for the prevention and treatment of hypertension in Chinese adults in 2018, the prevalence of hypertension was analyzed.Results:The median levels of systolic blood pressure, diastolic pressure and pulse pressure were 152.0, 76.0 and 76.5 mmHg, respectively. Blood pressure level was higher in females than in males. The prevalence of hypertension was 71.9%, mainly in isolated systolic hypertension with the prevalence of 60.1%. The results of multivariate analysis showed that the risk of hypertension in women was higher than that in men ( OR=1.624, 95% CI: 1.155-2.283), and the risk of hypertension in the northern ( OR=0.625, 95% CI: 0.434-0.901) and central areas ( OR=0.586, 95% CI: 0.346-0.993) was lower than that of the Eastern. Conclusion:The prevalence of hypertension, mainly in isolated systolic hypertension, showing gender and regional distribution differences.

Objective:To explore the prevalence of lipid profile and the influencing factors of dyslipidemia in centenarians in Hainan province, and provide basic data for the study of the lipid profile in centenarians.Methods:The data of this study were from the baseline data of China Hainan Centenarian Cohort Study from June 2014 to December 2016. A total of 1 002 centenarians were recruited. According to the guidelines for the prevention and treatment of dyslipidemia in Chinese adults in 2016, the prevalence of lipid profile were described and the prevalence of dyslipidemia with different clinical classifications were compared, and the main influencing factors were analyzed.Results:The median levels of TC, TG, LDL-C and HDL-C were 4.60 mmol/L, 1.05 mmol/L, 2.77 mmol/L and 1.41 mmol/L, respectively, in centenarians in Hainan. Blood lipid profile level was higher in females than in males. With the increase of BMI, TC, TG and LDL-C increased significantly, while HDL-C decreased significantly. The total prevalence of dyslipidemia was 19.1%. Smoking, BMI and area distribution were the main influencing factors of dyslipidemia.Conclusion:The prevalence of dyslipidemia in centenarians in Hainan was at a low level compared with other countries, and the blood lipid profile level was higher in females than in males.

Objective:To analyze the association of waist circumference, BMI, waist-hip ratio, waist-height ratio, calf circumference and waist-calf circumference ratio (WCR) with depression risk in centenarians in Hainan province.Methods:A total of 1 002 centenarians in Hainan were selected by cluster sampling. GDS-15 was used to investigate the depression. Multivariate linear regression and logistic regression analyses were conducted to evaluate the correlation between anthropometric indicators and depression risk. Restricted cubic spline was used to analyze and visualize the linear relationship.Results:After adjusting demographic characteristics (gender, age, ethnic group, marital status, educational level and type of residence) and lifestyle (smoking and drinking), the standard β of BMI, WC, WHR, WHtR, calf circumference and WCR associated with GDS-15 were -0.069, -0.032,0.009, -0.009, -0.099 and 0.060, respectively, and the P values of BMI and calf circumference were <0.05. With the increase of calf circumference, the risk of depression decreased, OR value was 0.94 (95% CI:0.90-0.98), and after adjustment, the results were still significant. Classified variable analysis indicated with the decrease of calf circumference and the increase of WCR, the risk of depression increased gradually, the trend P values were 0.038 and 0.042, respectively. Conclusion:Central obesity (waist circumference and WCR) and periphery obesity (calf circumference) have differed effects on depression in centenarians, and increased calf circumference is a protective factor for depression in female centenarians, attention should be paid to the mental health of the elderly women with lower calf circumference.

In recent years, occupational stress has become a focus of public attention in public health in China and abroad. Radiation workers are exposed to ionizing radiation in their daily work, which further exacerbates their levels of occupational stress. This not only affects their physical and mental health, but also increases the potential for radiation incidents or accidents. Based on the literature on occupational stress among radiation workers in China throughout the years, this article provides a summary, conclusion, and systematical analysis of the research status of occupational stress among radiation workers, with a detailed sorting of the data. It explores key research issues and directions and provides reference for future work.