A preliminary analysis of individual neutron dose monitoring with 6LiF-7LiF and CR39 / 中国辐射卫生

Objective To preliminarily compare 6LiF-7LiF and CR39 in individual neutron dose monitoring, and to provide a reference for improving individual neutron dose monitoring. Methods According to the GBZ 128-2019, 26 radiation workers from 7 institutions received individual neutron dose monitoring with 6LiF-7LiF and CR39 at the same time. The monitoring results were analyzed. Results For most of the workers, the personal neutron dose equivalent Hp(10) was less than the minimum detectable level. The results with the two monitoring methods differed in 6 of 26 workers. Conclusion Both 6LiF-7LiF and CR39 monitoring methods can be used for individual neutron dose monitoring for radiation workers, but the difference between 6LiF-7LiF and CR39 (in threshold energy, energy response, etc.) should be considered so that different types of radiation workers receive appropriate individual neutron dose monitoring.

Research progress in personal neutron dose monitoring / 中国辐射卫生

With the extensive use of neutron sources in industry, medicine, and scientific research, the number of people exposed to neutron has been increasing, which highlights the importance of personal neutron dose monitoring in the field of radiation protection. In the past decades, researchers have developed and improved a variety of techniques and methods for personal neutron dose monitoring. This paper focuses on the problems and research progress of track dosimeters (solid-state nuclear track dosimeters and fluorescent nuclear track dosimeters), luminescent dosimeters (thermoluminescent dosimeters and optically stimulated luminescent dosimeters), and bubble dosimeters in personal neutron dose monitoring.

An investigation of indoor radon concentrations and estimation of public exposure doses in Yinchuan, China / 中国辐射卫生

Objective To primarily investigate the indoor radon concentrations in the urban and rural dwellings in Yinchuan, China, and to estimate the effective dose. Methods A total of 67 dwellings, which included 49 urban households and 18 rural households in Yinchuan, were selected to cumulatively measure the indoor radon concentrations for more than 3 months using solid state nuclear track detection. Results The arithmetic mean, geometric mean, median, and range of indoor radon concentrations in urban and rural areas in Yinchuan were 64 Bq/m3, 59 Bq/m3, 57 Bq/m3, and 25-172 Bq/m3, respectively. Surveillance sites with an indoor radon concentration higher than 100 Bq/m3 accounted for 7.5%. Indoor radon concentrations in rural areas were higher than those in urban areas. Indoor radon concentrations were highest in winter and lowest in summer. The effective dose of indoor radon exposure among residents in Yinchuan was 1.86 mSv/a. Conclusion The results of indoor radon concentrations measured in this investigation in Yinchuan are significantly higher than those measured in the 1990s. The annual effective dose is higher than the mean levels in the world and China.

Indoor radon concentration and its changing trend in northeastern China / 中国辐射卫生

@#<b>Objective</b> To investigate the indoor radon concentration and its changing trend in northeastern China. <b>Methods</b> We measured indoor radon levels cumulatively for over three months by solid state nuclear track detection in a total of 261 houses in multi-story or high-rise buildings in Shenyang, Changchun, Harbin, Heihe, and Yichun in northeastern China. The measurement lasted one year in Changchun for seasonal changes. <b>Results</b> The average indoor radon concentration in the five cities was 88 Bq/m³, ranging from 12 to 558 Bq/m³. The indoor radon concentrations were ≤ 100 Bq/m³ in 75.1% of the houses, and ≤ 300 Bq/m³ in 97.7% of the houses. The indoor radon concentration increased with the age of buildings. The indoor radon concentration was highest in winter, and it was higher in summer than in autumn and spring. <b>Conclusion</b> The indoor radon concentration in northeastern China increased compared with the data of 1980s and 1990s. It is highest in the winter heating season, and higher in summer than in spring and autumn. Indoor radon exposure deserves attention.

Ambient radiation of patients undergoing 18F-FDG PET/CT myocardial metabolism imaging / 中国辐射卫生

Objective To study the ambient radiation of patients undergoing 18F-FDG PET/CT myocardial metabolism imaging, and to provide data for protection of surrounding people against radiation. Methods A total of 33 patients were selected for 18F-FDG PET/CT myocardial metabolism imaging. Dose equivalent rate was measured at the height of patient chest, in different directions, at different time points and at different distances, to investigate the distribution of ambient radiation of the patient. Results At the same time point and distance, the dose equivalent rates at the left and right sides of the patient were lower than the front and back sides. The dose equivalent rate at 1 m in front of the patient was 13-21 μSv/h after 18F-FDG injection, and decreased to 5-14 μSv/h after PET/CT imaging, with a mean decrease of 46%. The ambient dose equivalent rate decreased exponentially with distance (10~300 cm), and the mean power was −1.2. Conclusion The ambient radiation of patients undergoing 18F-FDG PET/CT myocardial metabolism imaging was high after 18F-FDG injection, and the ambient dose equivalent rate decreased rapidly with time and distance. Our results suggest that patients undergoing myocardial metabolism imaging should avoid prolonged and close contact with other people on the day of examination.

Application and analysis of radon-reduction methods in indoor radon pollution control / 中国辐射卫生

@#<b>Objective</b> To investigate the suitable methods for reducing the concentration levels of residential radon and its daughters. <b>Methods</b> 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. <b>Results</b> 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. <b>Conclusion</b> 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.

Building management and effect evaluation of high radon in geothermal field / 中国辐射卫生

Objective To explore the source and control of radon in high radon houses in geothermal fields; Methods Radon concentration in indoor and soil was measured by ATD detector in winter and summer; radionuclides in building materials were measured by gamma-ray spectrometry; radionuclides dose rates of building materials were measured by 6150 A D/ 6H X-γ ray detector; and radon reduction technology was applied to one of the houses;Results The average radon concentrations in 32 rooms were （106.4 ± 63.7） Bq/m3 (summer) and （421.3 ± 138.2） Bq/m3 (winter), and the concentrations in 12.5% (summer) and 96.9% (winter) of the rooms exceed 150 Bq/m3. The average radon concentration in soil around buildings was 12890 Bq/m3 (n = 24), which is 1.7 times of the typical soil radon concentration in Beijing (7600 Bq/m3). After soil decompression, the radon concentration in the house could be reduced to less than 100 Bq/m3. The radon reduction rates of active decompression and passive decompression were 94.6% and 71.4%, respectively. Conclusion The effect of soil decompression on reducing radon concentration in the bottom rooms is obvious. Attention should be paid to the radon in residential environment of geothermal field.

Preliminary investigation of radon concentration in drinking water in 31 cities of China / 中华放射医学与防护杂志

Objective:To obtain the distribution characteristics of radon levels in drinking water in cities of China and analysis their influencing factors.Methods:A total of 31 cities were selected and 406 tap water samples were collected in accordance with the sampling plan based on administrative division. Radon concentrations in the water samples were determined by using RAD7 H 2O measuring devices, and the closed loop liquid-gas balance method and grab method . The radon concentrations in the gas loop were measured by using semiconductor detector. After four measurement periods, radon concentrations in water were calculated. Results:The arithmetic mean of radon concentrations in drinking water from 31 cities was (4.92±9.44) Bq/L and the geometric mean (0.71±7.77) Bq/L, ranging from less than the lower detection limit (LLD) to 43.15 Bq/L. For 84.2% of drinking water samples, radon concentrations were less than US EPA recommended 11.1 Bq/L, all lower than the EU-recommended value of 100 Bq/L.Conclusions:The radon concentrations in drinking water are higher in northeastern, northwestern, southwestern, northern China than those in southern, central China and eastern China. The factors influencing radon concentrations in drinking water are closely related to geological structure and water source type. Compared with the global values, the radon concentrations in drinking water in our cities are low and safe in general in China.

The effect of rehabilitation nursing intervention on the model of joint contracture in rats / 中国实用护理杂志

Objective:To explore the curative effect of rehabilitation nursing on the rat knee model of post-traumatic joint contractures.Methods:Male Wistar rats ( n=40), weighing between (180±20) g, were randomly divided into control group ( n=8) and experimental group ( n = 32) by random number table. The left knee was surgically immobilized in the experimental group which by external fixation for 4 weeks which applied the Nagai method established the model of post-traumatic joint contractures, the group also divided into four groups namely experimental control group, rehabilitation nursing intervention group, drug intervention group and exercise intervention group, 8 rats in each group and they were given different interventions. After 4 weeks interventions each rat was photographed with X-ray in order to measure the range of motion of the left knee joint range of motion (ROM), the joint muscle and synovial tissue of the animals were subjected to morphological analysis. Results:The ROM of left knee joint in experimental group (74.74±9.23) ° was lower than that of in control group (109.72±5.74) ° after 4 weeks immobilization, the difference was statistically significant ( t value was 12.237, P < 0.01), which showed that the model of joint contractures was established successfully. Compared with the experimental control group ROM (72.20±12.73) °, the difference of ROM (103.54 ±4.36)° in rehabilitation nursing intervention group and ROM (98.13 ±11.20) ° in drug intervention group were significantly higher ( t value was, P < 0.05). The results of pathological section showed that the gloss of muscle tissue in the rehabilitation nursing intervention group and the muscle fiber arrangement in the drug intervention group were close to those in the control group. Conclusion:Rehabilitation nursing intervention can not only improve ROM of joint contracture model animals, but also promote the recovery of joint muscle tissue structure.

Association between self-reported snoring and hypertension among Chinese Han population aged 30-79 in Chongqing, China

BACKGROUND@#We aim to explore the association between self-reported snoring and hypertension among adults aged 30-79 in Chongqing, China.@*METHODS@#A total of 23,342 individuals aged 30-79 were included at baseline from August 2018 to January 2019, and the final sample size for the analysis was 22,423. Face-to-face interviews and physical examinations were conducted by trained investigators. Logistic regression was performed to study age-specific and gender-specific associations between snoring and hypertension.@*RESULTS@#Frequent snoring was associated with the risk of hypertension for each age and gender group, and the frequency of snoring was positively correlated with the risk for hypertension. For the three age groups (< 45, 45-59, ≥ 60), compared with the non-snoring group, those who snore often had a 64.5%, 53.3%, and 24.5% increased risk of hypertension (< 45: OR = 1.65, 95%CI 1.34-2.02; 45-59: OR = 1.53, 95%CI 1.37-1.72; ≥ 60: OR = 1.25, 95%CI 1.09-1.42), respectively. For men and women, those who snore often had a 46.8% and 97.2% increased risk of hypertension, respectively, than the non-snoring group (men: OR = 1.47, 95%CI 1.33-1.63; women: OR = 1.97, 95%CI 1.75-2.23).@*CONCLUSIONS@#People who snore frequently should pay close attention to their blood pressure levels in order to achieve early prevention of hypertension, particularly for snorers who are female and aged under 45; importance should be attached to their blood pressure control.

Research on Procurement Classifcation of Medical Equipment Based on Kraljic Model / 中国医疗器械杂志

Based on the Kraljic model,this paper established the scoring standard system for medical equipment procurement,and determined the weight coefficients of each evaluation factor by the analytic hierarchy process (AHP),then the procurement classification model of medical equipment was successfully established.It is proved that this model can classify medical equipment effectively,which enables the purchasing personnel to adopt corresponding purchasing strategies according to different classification.This model can be extended to all medical equipment procurement,realizing the delicacy and individualized procurement management of the equipment,which has strong operability and guiding significance.

The feasibility study of gold nanoparticle composites (ssDNA-AuNPs) for the colorimetric detection of gamma radiation dose / 中华放射医学与防护杂志

Objective To establish a simple and convenient method and study the feasibility of using gold nanoparticle composites (ssDNA-AuNPs) for colorimetric detection of gamma radiation.Methods The composites ssDNA-AuNPs were prepared by applying the ssDNA to the surface of AuNPs,and then were irradiated with gamma ray with absorbed doses of 0,5,10,20,and 30 Gy,respectively.Subsequently the color change in the solutions were observed simultaneously with absorption spectra being measured.The linear relationship between the ratio of A625/A521 in the absorption spectrum and the absorbed dose was established.Results With the increase of radiation dose,the color of the solutions changed from wine-red to blue-violet gradually,the ratio of A625/A521 in absorption spectra had excellent liner response for absorbed dose ranging from 0 to 30 Gy,and the linear equation was A625/A521 =0.020 6 + 0.303 6 E(R2 =0.991 5).Conclusions The ssDNA-AuNPs synthesized in this experiment can be successfully used for colorimetric detection of gamma absorbed dose,and a simple and convenient method for detection of gamma radiation has been newly established.

Analysis of intercomparison results for radon-thoron discriminative detector / 中华放射医学与防护杂志

Objective To increase the cumulative measurement level of 222 Rn and 220 Rn and ensure the accuracy and reliability of the measurement result . Methods By using improved 222 Rn-220 Rn discriminative detectors ( LD-P detectors) , the radon research group of National Institute for Radiological Protection Chinese Center for Disease Control and Prevention participated with the intercomparison organized by National Institute of Radiological Science ( NIRS) , Japan. Specifically, with the 222 Rn-220 Rn discriminative detectors being sent to Japan, the comparison was completed under different conditions in the 222 Rn chamber and 220 Rn chamber in NIRS. After exposure, the detectors were sent back to our laboratory for etching and analysis, and then measurement result were informed to NIRS. Finally, NIRS returned the exposure reference values of 222 Rn and 220 Rn to our laboratory. Results Under the conditions of high and low levels of 222 Rn, the relative percentage differences ( RPD ) between the measured values and the reference value provided by the NIRS were -12. 0％ and -11. 8％, respectively, while coefficients of variation ( COV) were 3. 0％ and 6. 2％, respectively. Under the conditions of high level and low levels of 220Rn, the relative percentage differences (RPD) between the measured value and the reference value provided by the NIRS were -0. 8％ and -8. 0％, respectively; coefficients of variation ( COV ) were 6. 7％ and 4. 5％, respectively. Conclusions This intercomparison result were categorized by NIRS ( PRD<10％) , with the satisfactory result of LD-P detectors available.

Research on the Clinical Alarm Management Mechanism Based on Closed-loop Control Theory / 中国医疗器械杂志

This paper proposes a clinical alarm management system based on the theory of the closed loop control. The alarm management mechanism can be divided into the expected standard, improving execution rule, rule execution, medical devices with alarm functions, results analysis strategy and the output link. And, we make relevant application and discussion. Results showed that the mechanism can be operable and effective.

Study on relationship between indoor radon concentration and air exchange rate for new residential buildings / 中华放射医学与防护杂志

Objective To investigate the relationship between indoor radon concentration and air exchange rate for new residential building.Methods The indoor radon concentration and air exchange rate were measured in two new roughcast houses in Guangzhou and Hefei,respectively.The radon concentration was measured using radon instrument.The air exchange rate was measured by using tracer gas dilution method.Results The indoor radon concentrations measured in Guanzhou for two bedrooms in a 48-hour closed condition were 106 and 115 Bq/m3,the range of 17-181 and 6-224 Bq/m3.Air exchange rates were 0.16/h and 0.21/h.In Hefei,the twice measured values for one bedroom were 148 and 186 Bq/m3,the range of 8-224 and 14-290 Bq/m3,and air exchange rates were 0.14/h and 0.12/h.The indoor radon concentration exponentially decreased with the increase of air exchange rates.Conclusions Attention should be paid to the indoor radon pollution issue that may arise in new residential buildings of energy-saving design due to low air exchange rate.

Micro vibration with the hand nursing methods on the disuse syndrome patients with constipation nursing effect assessment / 中国实用护理杂志

Objective To investigate the micro vibration with the hand nursing methods for disuse syndrome patients constipation curative effect. Methods During the time of March 2016 to September, 76 patients who had long term disuse syndrome with the constipation in two Elderly Care Homes in Urumqi were randomly divided into intervention group (n=37) and control group (n=39), in the experimental group, was treated by manual micro vibration nursing method which included hand micro vibration therapy, exercise therapy, health education guidance once a day, 50 minutes each time, a total of 4 weeks of intervention, while the control group received routine rehabilitation nursing. Before the intervention, intervention after 4 weeks, follow-up period after the end of 8 weeks according to the symptoms of constipation and evaluate the stool frequency. Results Preliminary experimental group and control group patients have different degrees of constipation symptoms, with the hand micro vibration method of nursing intervention, the experimental group had not constipation of symptoms, 17(43.6%) had constipation symptoms in the control group. Compared with the incidence of two groups of constipation patients. Before the intervention, intervention after 4 weeks, follow-up period after the end of 8 weeks, the experimental group patients defecation frequency was (5.33 ± 1.47), (29.70 ± 6.49) , (43.41 ± 6.15)times, The control group patients was(5.77 ± 1.39), (13.10 ± 1.27), (21.15 ± 4.23) time, comparison of the two groups, t=-1.357, 15.275, 18.458, P=0.179, 0.000, 0.000. Conclusions Hand micro vibration nursing method has remarkable effect on relieving constipation, and the treatment effect can be maintained for a long time, no recurrence occurred and adverse reactions, however, this method also economic, convenient, less time consuming and efficient.

Study on groundwater radon concentrations and its dose contribution in some cities in China / 中华放射医学与防护杂志

Objective To investigate the levels and distribution of radon concentrations in groundwater in some representative cities in China,and estimate the effective dose from inhaled radon released from domestic groundwater.Methods A total of 12 cities in 7 provinces (municipalities) were selected,including Beijing,Inner Mongolia,Ningxia,Shaanxi,Henan,Liaoning and Heilongjiang.In total,73 water samples from groundwater supply were taken.Radon concentrations in water samples were determined by using a continuous radon monitor with air-water exchanger.Results The average radon content in groundwater for drinking was 11.8 Bq/L in 12 cities in 7 provinces,ranging from 1.0 to 63.8 Bq/L.The radon concentrations in 37％ water samples exceeded 1 1.1 Bq/L,the safe limit recommended for drinking water by the United States Environmental Protection Agency (EPA).The radon contents in all of the water samples was lower than the reference level 100 Bq/L recommended by World Health Organization (WHO).The average annual effective dose arising from inhaled radon released from groundwater was 29 μSv (2.4 to 160 μSv).Conclusions Generally,the effective dose from inhaled radon released from groundwater is negligibly low.However,in some areas dominated by granite bedrock,the dose contribution from radon released from groundwater to residents should be routinely monitored.

Discussion on Quality Evaluation Method of Medical Device During Life-Cycle in Operation Based on the Analytic Hierarchy Process / 中国医疗器械杂志

The content related to the quality during life-cycle in operation of medical device includes daily use, repair volume, preventive maintenance, quality control and adverse event monitoring. In view of this, the article aims at discussion on the quality evaluation method of medical devices during their life cycle in operation based on the Analytic Hierarchy Process (AHP). The presented method is proved to be effective by evaluating patient monitors as example. The method presented in can promote and guide the device quality control work, and it can provide valuable inputs to decisions about purchase of new device.

Levels and distribution of indoor radon concentrations in Shenzhen, China / 中华放射医学与防护杂志

Objective To investigate the levels and distribution of radon in dwellings in Shenzhen cities of China.Methods A total of 108 low-,multi-,middle-and high-rise buildings were selected.Indoor radon concentrations were measured by using solid track detector.Results The arithmetic mean of indoor radon concentrations in Shenzhen was 64 Bq/m3,and geometric mean was 58 Bq/m3,in range of 15 to 155 Bq/m3.The average indoor radon concentration in Bao'an district was 50 Bq/m3 with the lowest value,and that in Pingshan new district was 87 Bq/m3 with the highest value.There were 12 measuring points where indoor radon concentrations were higher than 100 Bq/m3 in Shenzhen,accounting for 11.1％ of the total number.Shapiro-Wilk test showed that the frequency distribution of indoor radon concentration in Shenzhen follows lognormal distribution (P ＞ 0.05).The indoor radon concentrations showed a downward trend from 1990 to 2015.The indoor radon concentration decreases with the elevated floors except 10th and above floors.Conclusions The indoor radon concentrations in Shenzhen increased by 35％,compared to the previous investigations.It is recommended that efforts continue to improve radioactive materials standards about building material and to enhance the natural ventilation in high-rise buildings in order to lower the radiation hazards from radon.

Investigation and analysis of radon concentrations in two groundwater supplies in a city / 中华放射医学与防护杂志

Objective To explore the effect of radon released from water on the indoor radon activity concentration in groundwater supplies.Methods Two groundwater supplies in a city were chosen.Radon concentrations in three kinds of water samples were determined by using a continuous radon monitor with air-water exchanger,including source water,finished water and tap water.The solid track detector was used to analyze the indoor radon concentration in water supplies.Results The concentrations of radon in source water,finished water and tap water were (7.59 ± 1.36),(3.56 ±0.86),(3.68 ±0.81)Bq/L and (12.19 ±0.57),(7.87 ± 1.12),(9.50 t 1.12) Bq/L,respectively.The concentration of radon was the highest in source water and at less varying level in finished water and tap water.Aeration and filtration tank process significantly decreased radon activity in water.Radon concentrations in aeration and filtration rooms were 4 218 Bq/m3 and 1 937 Bq/m3,respectively,which exceeded the limit in work place (1 000 Bq/m3).Conclusions Aeration and filtration workplaces for groundwater supplies were found to contain elevated radon concentrations in air,which was released from groundwater.Radon issues in groundwater supplies in China should be paid more attention.