Objective To develop a portable nuclear radiation detector with low-energy γ-nuclide recognition capability for rapid measurement of the dose levels in low-energy radiation fields and identification of nuclides. Methods A digital multi-channel circuit was developed for a detector based on the room temperature semiconductor cadmium zinc telluride, nuclide recognition was achieved using an intelligent nuclide recognition algorithm, and the energy response function G(E) was used to calculate the real-time ambient dose equivalent rate H*(10). Results The portable spectrometer had a minimum detectable energy of 20 keV, and the typical energy resolution for low-energy X-rays was > 4.10% at 59.5 keV and 20℃, enabling accurate identification of ²⁴¹Am nuclide. Conclusion The device has a good measurement performance for low-energy γ/X rays, effectively addressing the limitations of existing devices for monitoring low-energy radiation fields, and provide reliable technical methods for monitoring and emergency response in spent fuel reprocessing plants or nuclear material production plants.

Since the implementation of the Measures for the Management of Radiation Workers’ Occupational Health in November 2007, it has played an extremely important role in protecting the occupational health of radiation workers. There are more than 700 000 radiation workers in about 100 000 workplaces with potential radiation exposure, as well as a large number of miners exposed to high levels of radon. As the radiation health monitoring project suggests, measures of occupational health management such as personal dose monitoring and occupational health examination of radiation workers have been widely implemented and achieved good results in the protection of radiation workers. However, the risks of chromosomal aberration and specific turbidity of the eye lens of radiation workers have increased in high-risk positions such as interventional radiology, nuclear medicine, and industrial flaw detection. The control of high radon exposure in miners needs to be strengthened. It is necessary to adapt to the new situation in view of new challenges and actively promote the revision of the Measures for the Management of Radiation Workers’ Occupational Health, so as to further improve the occupational health management of radiation workers in China.

Objective To construct a rapid prediction system to improve the accuracy and efficiency of evaluation of the consequences of nuclear accidents at a field scale. Methods Base on a diagnostic wind field model and Lagrangian particle diffusion, we established a rapid prediction method for wind field and pollutant dispersion around complex underlying surfaces within a field scale, in a way of visual discrimination of buildings and vegetation distribution. With data simulation and the use of a real urban field example, the simulated results were compared with wind tunnel test measurements and computational fluid dynamics results to study the influence of complex underlying surfaces on wind field and pollutant transport in the region. Results The rapid prediction system could clearly simulate the high-resolution wind field and pollutant concentration distribution of the region in about five minutes. It could interface with geographic information software and couple with a mesoscale weather prediction model. In terms of accuracy, the system performed well in wind field simulation, with the fractional deviations of wind speed and wind direction being 0.33 and −0.08, respectively. Concentration field simulation was greatly affected by the wind field, and the ratios of simulated concentrations to observed concentrations were between 0.05 and 3.4, except for a few low concentration points. Conclusion The rapid prediction system can effectively simulate the distribution characteristics of the flow field and improve calculation efficiency when ensuring calculation accuracy, which provides an important reference for emergency response to nuclear accidents.

Objective To investigate GATA3 expression and the regulatory mechanism of m⁶A modification in the response of alveolar epithelial cells to radiation, and to provide a new therapeutic target for radiation-induced lung injury based on its pathogenesis. Methods Human lung epithelial cell line (A549) and mouse lung epithelial cell line (MLE-12) were exposed to X-ray irradiation with a single dose of 10 Gy (dose rate 1 Gy/min) and 6 Gy (dose rate 0.75 Gy/min), respectively. The expression of VIRMA gene (RNA methylase) was inhibited by lipofection of A549 cells and MLE-12 cells with shRNA-VIRMA plasmid and siRNA-VIRMA interfering fragment, respectively. Quantification of m⁶A RNA methylation was performed by colorimetry. Changes in the expression of mRNAs of VIRMA, GATA3, and epithelial-mesenchymal transition (EMT) markers in irradiated A549 and MLE-12 cells were determined by qRT-PCR. Changes in the expression of VIRMA, GATA3, and EMT marker proteins in irradiated A549 and MLE-12 cells were determined by Western blot. Results Radiation up-regulated the expression of methylase VIRMA in A549 and MLE-12 cells, which in turn enhanced the m⁶A of total RNA and the expression of GATA3 gene and protein, resulting in EMT. Furthermore, in A549 and MLE-12 cells, interference of the VIRMA gene significantly reduced the expression of GATA3 gene and protein and the expression of EMT-related molecules. Conclusion Radiation induces m⁶A modification in alveolar epithelial cells, which up-regulates the expression of GATA3 gene and induces EMT, thus playing an important role in the process of radiation-induced lung injury.

In the current clinical diagnosis, medical images have become an important basis for diagnosis, and different modes of medical images provide different tissue information and functional information. Single-mode images can only provide single diagnostic information, by which difficult and complicated diseases cannot be diagnosed, and comprehensive and accurate diagnostic results can be obtained only with the help of multiple diagnostic information. The multimodal fusion technology fuses multiple modes of medical images into single-mode images, and thus the single-mode images contain complementary information between multiple modes of images, so that sufficient information for clinical diagnosis can be obtained in a single image. In this paper, the multimodal medical image fusion methods are sorted into two types, namely the traditional fusion method and the fusion method based on deep learning.

Objective To analyze the problems and solutions in the diagnosis of a patient with occupational radiogenic neoplasms. Methods The dose conversion method was selected in dose estimation. Personal dose equivalent, skin absorbed dose, and reported detection data were converted into red bone marrow absorbed dose. The upper 95% confidence limit of the probability of causation (PC 95%) was calculated. Results The PC 95% of cancer due to radiation in the worker was 66.38%, which suggested occupational radiogenic neoplasms. Personal dose data were missing in dose estimation. The current dose estimation standard lacked bedside radiography and CT operation type, and the dose conversion formula was not perfect. Conclusion In the judgment of occupational radiogenic neoplasms, the estimated dose showed uncertainty. There is an urgent need to formulate and promulgate dose estimation standards that are operational and in line with the current development of radiological diagnosis and treatment technology and equipment.

Objective To evaluate the radiation protection of “four-in-one” dental X-ray equipment and to investigate the safety interlock of the equipment by measuring the scattered radiation at the position of the patient during operation. Methods A cone-beam CT dental phantom was used to simulate the patient’s head. The intra-oral and extra-oral components of the “four-in-one” X-ray equipment were installed in a 5 m² room. The scattered radiation at patient position was measured using a γ/X-ray survey meter, and the effects of intra-oral and extra-oral components were compared. Results For a 5 m² room, when CBCT was exposed under typical conditions, the dose at the patient's position was 10.70 uSv/h when there was an intra-oral component and 10.60 uSv/h when there was no intraoral component. The intra-oral part did not affect the radiation dose at the patient's position. When the intra-oral component was exposed, the dose rate at the patient's position was 4.05-6.85 uSv/h, and the extra-oral part did not affect the scattered dose of the patient examined with intra-oral components.Conclusion The evaluation of radiation protection of new equipment must comprehensively consider radiation safety and equipment operation safety. The results of this study provide suggestions for clinical radiation protection supervision and evaluation of “four-in-one” dental X-ray equipment.

Objective To improve the determination of gross α and gross β radioactivity in soil, establish a fast and accurate method for soil radioactivity analysis, and provide a basis for establishing standard methods for analysis of gross α and gross β radioactivity in soil. Methods Using the method of soil nuclide extraction and the sample preparation method for low background α/β counter, an extraction-enrichment method was established to monitor the radioactivity of gross α and gross β in soil. Meanwhile, the radioactivity of gross α and gross β in the same soil samples was determined using the direct paving method. An optimal method of monitoring gross α and gross β radioactivity in soil was put forward by comparing the advantages and disadvantages of the two methods. Results With the direct paving method, the radioactivity of gross α and gross β in soil was 0.47 Bq/g and 0.85 Bq/g, respectively; and the minimum detection limit was 0.04 Bq/g and 0.02 Bq/g, respectively. With the extraction-enrichment method, the radioactivity of gross α and gross β in soil was 0.32 Bq/g and 0.29 Bq/g, and the minimum detection limit was 0.02 Bq/g and 0.01 Bq/g. Conclusion Comparison of the two detection methods showed that the direct paving method is more accurate and easier to operate, while the extraction-enrichment method is complex in operation and has relatively large system error but provides a lower minimum detection limit.

Due to the continuous development of nuclear power technology and the wide application of ionizing radiation in China, an increasing number of occupational groups and the general public have been exposed to the low-dose ionizing radiation environment. Consequently, research has focused on related health effects (carcinogenic and non-carcinogenic effects). There is no consensus on the health effects of long-term low-dose ionizing radiation exposure on populations. This article reviews the health effects of low-dose ionizing radiation identified worldwide to provide a scientific basis for investigating the mechanisms of such effects and developing population protection strategies.

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.

Objective To develop a simplified phantom for the calibration of whole-body counters. Methods A simplified phantom design method for the calibration of whole-body counters was established based on the process and method of calibrating whole-body counters. By using the established method and Monte Carlo method, a simplified phantom including the total body, thyroid, lungs, and gastrointestinal tract was designed to calibrate the ORTEC-Stand FAST II whole-body counter. The simplified phantom was compared with the BOMAB phantom through experimental measurements. Results Within the range of 50 keV to 2 MeV, for rays of the same energy in the same organ of the simplified phantom and BOMAB phantom, the simulated data of detection efficiency by whole-body counting showed an error within 5%, and the experimental measurements showed an error within 10%. Conclusion We developed a simplified phantom for the calibration of the whole-body counter, demonstrating the feasibility of using the simplified phantom instead of a physical body phantom for whole-body counter calibration, which can greatly facilitate whole-body counter calibration for internal radiation monitoring.

Objective To assess the retention of ²⁴¹Am in the whole-body bone of worker by measuring the retention of ²⁴¹Am in the skull. Methods A whole-body counter with high-purity germanium detector was used to measure the 59.5 keV full-energy peak count of ²⁴¹Am in the skull. The efficiency of the measurement was calibrated by the digital skull phantom combined with the geometric model of the detector. The retention of ²⁴¹Am in the worker’s skull was calculated. Results The proportion of skull dry weight relative to the whole-body bone dry weight was used as the coefficient to calculate the ²⁴¹Am deposition in the whole-body bone from the measured activity of skull ²⁴¹Am. Conclusion With the retention of ²⁴¹Am in the skull and the proportion of skull dry weight, the retention of ²⁴¹Am in the whole-body bone of the worker was calculated to be about 806 Bq.

Objective To determine the responses of radioactivity meter at different positions in the vertical direction of the ionization chamber by measuring different radioactive sources. Methods The radiation of cesium-137, cobalt-60, and americium-241 nuclides was measured at different positions in the vertical direction of the ionization chamber with commonly used clinical radioactivity meters. The measured values were fitted to obtain three trend lines. The maximum deviation of the measured values was estimated according to the trend line, and the deviation was estimated at different syringe needle heights. Results According to the trend lines, the maximum deviation of the radioactivity meter CRC-55tR in measuring cesium-137, cobalt-60, and americium-241 nuclides was 5.15%, 5.98%, and 6.25% respectively. The radioactivity meter RM-905a was used to measure three nuclides at different syringe needle heights, and the maximum deviations were −4.33%, −9.9%, and −12.65%, respectively. Conclusion The three nuclides showed different change patterns in measurement with CRC-55tR and RM-905a but similar change patterns in measurement with the same radioactivity meter. The values measured with the same radioactivity meter showed significant deviations at different positions in the vertical direction of the ionization chamber. It is recommended to make position correction for commonly used nuclides. Reducing measurement error and improving measurement accuracy of nuclides are of great significance for radiation protection.

Objective To determine the current status of occupational internal exposure to ¹³¹I in the thyroid of nuclear medicine workers, to explore the influencing factors for internal exposure, and to provide a basis for the radiation safety management of nuclear medicine. Methods The cluster sampling method was used to select 162 workers practicing ¹³¹I treatment in 24 hospitals in Hubei Province, China. Thyroid ¹³¹I activity levels were measured in vitro using a portable γ-spectrometer, and the committed effective dose was estimated. Results The thyroid ¹³¹I activity detected in 13 (54.17%) hospitals was above the lower limit of detection of the instrument. Two hospitals had the highest detection rates, 62.50% and 61.90%; the difference was significant compared with the remaining 11 hospitals (P < 0.0001). Thyroid ¹³¹I was detected in 34 workers in total, with a detection rate of 20.99% and a mean activity of 179.09 ± 138.71 (6.02-589.74) Bq. The highest detection rates were found in cleaners and nurses, which were 35.71% and 33.33%, respectively, with no significant difference in detection rate between positions (least P > 0.08). The mean value of the committed effective dose was 0.68 ± 0.52 (0.02-2.22) mSv/a in the 34 workers. Conclusion The ¹³¹I consumption and workplace ventilation may be important factors affecting the level of internal exposure. It is important to strengthen the training of nuclear medicine workers on radioprotection and workflow management, as well as the regular monitoring of occupational internal exposure for ¹³¹I treatment-related workers.

Objective To explore the feasibility of quartz glass for radiotherapy dosimetry through the experimental study of the thermoluminescence characteristics of synthetic quartz glass. Methods The thermoluminescence glow curves of quartz glass under different annealing conditions were analyzed, the thermoluminescence characteristics of quartz glass were studied, and the measurement parameters were optimized. Using the Co-60 reference radiation field in the National Secondary Standard Dosimetry Laboratory, the quartz glass samples under different annealing conditions were irradiated following the dose levels of radiotherapy, i.e., 0.5, 1.0, 2.0, 4.0, 6.0, 8.0, and 10.0 Gy, respectively. According to the relationship between the absorbed dose of quartz glass and the relative thermoluminescence signal intensity, the linearity and dispersion of the dose response of quartz glass were obtained, and the feasibility of quartz glass for radiotherapy dosimetry was analyzed. Results The linear correlation coefficient of dose response of quartz glass under annealing condition of 430℃ for 10 min was 0.9984, and the dose response dispersion was 0.97% at the absorbed dose of 2 Gy. The linear correlation coefficient of dose response of quartz glass under annealing condition of 600℃ for 1 h was 0.9911, and the dose response dispersion was 1.4% at the absorbed dose of 2 Gy. Conclusion Preliminary results suggest that quartz glass with annealing condition of 430℃ for 10 min has the potential to be used for radiotherapy dosimetry.

Objective To analyze the administrative penalties for radiation diagnosis and treatment in Xuzhou, China, 2018—2021, investigate the key illegal behaviors in radiation diagnosis and treatment, and provide a basis for effective supervision with targeted measures. Methods A total of 142 cases of administrative penalties were analyzed for the year of the case, the undertaker, the basic information of the subjects, the amount of penalty, and the specific illegal facts. Results From 2018 to 2021, the case number of administrative penalties for radiation diagnosis and treatment in Xuzhou was relatively stable. The cases were mainly undertaken by the municipal health supervision institution, while the number of cases handled by basic-level health supervision institutions was increasing. The administrative penalties were mainly imposed on persons and primary or non-classified medical institutions. Common illegal behaviors included occupational health management of radiation workers and personal protection during medical exposure. Conclusion We should focus on strengthening the publicity and supervision of personal protection in occupational health management and medical exposure, continue to improve the law enforcement ability of basic-level radiation health supervisors, develop a standardized management system for radiation diagnosis and treatment, innovate the supervision mode and radiation hazard notification mode, promote the “Internet + ” informatization supervision, and recommend to improve and revise radiation-related laws and regulations.

Objective Based on the measurement of the ambient dose equivalent rate of points around the novel self-shielding Zap-X radiotherapy system, its self-shielding effect was evaluated and analyzed, and suggestions were proposed for the revision and improvement of related standards in China. Methods The ambient dose equivalent rates were measured at 15 points around the Zap-X system under 6 system operating conditions. The radiation shielding effect of the Zap-X system was evaluated according to the domestic and international radiation protection standards of radiotherapy equipment. Results Measurement of ambient dose equivalent rate and dose evaluation showed that the shielding effect of the Zap-X system met the requirements of international standards, but the dose rates at some points failed to satisfy the reference control levels in the domestic standards. Conclusion Without the shielded treatment room, the self-shielding effect of the Zap-X radiotherapy system is insufficient to meet the requirements of domestic standards for radiation safety and protection. The system should be operated in the treatment room to meet domestic standards.

Objective To analyze the radionuclide levels in food and the committed effective dose due to food intake in residents around the Shidaowan Nuclear Power Plant (SNPP). Methods Daily food samples were collected within 30 km radius around the nuclear power plant in 2019—2022. The radioactivity levels before and after the operation of SNPP were determined. The data were combined with the dietary consumption of residents in Shandong province, China to estimate the committed effective dose. Results The radionuclides ²³⁸U, ²³²Th, ²²⁶Ra, and ⁴⁰K in food were at normal background levels, and the average radioactivity was (0.062 ± 0.004), (0.121 ± 0.007), (0.162 ± 0.010), and (92.4 ± 5.5) Bq/kg fresh weight. Trace ¹³⁷Cs and ⁹⁰Sr were detected in some food samples and the average radioactivity was (0.047 ± 0.003) and (0.193 ± 0.200) Bq/kg fresh weight. The levels of radionuclides did not increase after the operation of SNPP compared with that before operation. The estimated committed effective dose in residents due to food intake was 0.205 mSv. Conclusion The radioactivity of food in the area around SNPP shows no difference before and after operation, and the dose burden is low in local residents.

Objective To investigate the awareness of the Radiation Shielding Requirements for Radiotherapy Room–Part 2: Radiotherapy Room of Electron Linear Accelerators (GBZ/T 201.2—2011) among relevant practitioners in medical institutions as well as its implementation and application situation and collect relevant problems and suggestions for an evaluation of the scientificalness, standardization, and timeliness of the standard, and to provide a scientific basis for the further revision and implementation of the standard. Methods An online questionnaire survey was conducted among relevant employees in medical institutions providing medical linear accelerator radiotherapy across 22 provinces of China, which investigated the awareness, training, application, and revision suggestions related to GBZ/T 201.2—2011. The questionnaires were collected and analyzed. Results A total of 340 relevant practitioners filled out the questionnaire. Of the participants, 66.80% were physicists; 79.11% had an awareness of the standard; 56.18% ever participated in the standard-related training; but the survey results showed that the practitioners did not have a good knowledge of the standard’s content, and the training and promotion were not enough; 83.24% thought that the standard had been widely used; 17.60% thought that the standard needed to be revised; 76.76% thought that there was a need to add calculation examples; 88.82% thought that neutron shielding needed to be considered for the 10 MV X-ray accelerator room. Conclusion The standard has been widely known in the field of radiotherapy protection. With the development of radiotherapy technology, the standard should be revised to add calculation examples and consider neutron shielding in the 10 MV X-ray accelerator room. The standard is highly technical and difficult to grasp, so the promotion and implementation goals should be appropriate for different personnel groups, the training for employees at key posts should be strengthened, and the methods recommended in the standard should be uniformly used throughout the country.

Objective To investigate the gross alpha and gross beta radioactivity levels in drinking water around Shidao Bay Nuclear Power Plant before its operation. Methods Ten sampling sites were set up within 30 km of Shidao Bay Nuclear Power Plant. From 2018 to 2021, samples were collected during the dry season and wet season each year and were tested in a laboratory according to Standard examination methods for drinking water—radiological parameters (GB/T 5750.13—2006). Results From 2018 to 2021, the gross alpha radioactivity in drinking water within 30 km of Shidao Bay Nuclear Power Plant was within the range of about 0.004-0.420 Bq/L, which does not exceed the guided gross alpha radioactivity specified in the National Standard; from 2018 to 2021, the gross beta radioactivity level was about 0.008-1.050 Bq/L. In 2018, the gross beta radioactivity at the sampling site 4.7 km from the Nuclear Power Plant exceeded the guided level specified in the National Standards for Drinking Water Quality (GB 5749—2006), but it fell within the guided level in a repeat laboratory test after deducting the effect of ⁴⁰K on the gross beta radioactivity. Conclusion After deducting the effect of ⁴⁰K on the gross beta radioactivity, the gross alpha and gross beta radioactivity levels in drinking water within 30 km of Shidao Bay Nuclear Power Plant are within the guided levels specified in the National Standards.

Objective To evaluate the implementation, application, and problems and suggestions of the Radiation Shielding Requirements in Room of Radiotherapy Installations—Part 1: General Principle (GBZ/T 201.1—2007) through a survey of relevant personnel in radiation health technical service institutions, and to provide a scientific basis for further revision and implementation of this standard. Methods A questionnaire survey was conducted among randomly selected personnel in radiation health technical services across China, which mainly investigated the awareness, training, application, and revision suggestions related to the GBZ/T 201.1—2007. The results were aggregated and analyzed. Results A total of 184 evaluation questionnaires on the GBZ/T 201.1—2007 were collected from technical service staff in 25 provinces. Among the responders, 64.1% thought that the standard had been widely applied; 91.8% thought that the standard could meet work needs; only 54.3% ever received relevant training on the standard; 68.5% used the standard once or more per year; 33.7% thought that the standard needed to be revised. Conclusion The personnel in radiation health technical services have a high awareness rate of the GBZ/T 201.1—2007 and its contents, but their familiarity with and application of the standard need to be improved. Relevant departments should strengthen the training and promotion of the standard, and part of the standard should be revised.

The purpose of establishing nuclear power plants is to meet the growing energy demand. Unfortunately, there have been five major nuclear accidents in history, which have diverse and lasting effects on individuals and society. The well-known health effects are tissue reactions caused by high radiation doses and carcinogenic effects of low radiation doses. In recent years, studies on adult residents, mothers with young children, and clean-up/decontamination workers exposed to high doses of radiation in the areas affected by nuclear power plant accidents show long-term impacts on the mental health of these people. This paper reviews these psychological impacts.

Objective To analyze the results of national personal dose monitoring intercomparison and assessment of Hubei Provincial Hospital for Occupational Disease in 2016—2021, to investigate the influencing factors for monitoring results, and to improve the ability of personal dose monitoring. Methods The assessment was completed according to the requirements of The National Comparison Scheme for Individual Dose Monitoring Ability and Testing Criteria of Personnel Dosimetry Performance for External Exposure (GBZ 207—2016). Results The assessment results were qualified in 2016—2017 and 2020 and excellent in 2018—2019 and 2021. Conclusion The ability of personal dose monitoring in our laboratory has been continuously improved. The monitoring results are accurate and the data processing is standardized, which meet the requirements of relevant standards for personal external exposure dose monitoring.

Objective To develop a reasonable plan of monitoring personal internal exposure dose. Methods This paper introduced the methods of monitoring the individual dose and direct measurement of three representative radionuclides. Results The maximum monitoring periods were determined according to the radionuclide retention characteristics and the reporting standards and requirements, which were m(1)/m(T/2) ≤ 3 and m(T/2)/m(T) ≤ 3. The lower detection limit of the instrument was derived from the monitoring periods and the annual radionuclide intake limit, which should be lower than the derived method detection limit of the corresponding radionuclide. Then the measuring duration of the instrument that meets the corresponding conditions was derived from the derived method detection limit of the instrument and the maximum monitoring period. Conclusion Our results provide a reference for the formulation of a plan of monitoring personal internal exposure dose.

Objective To evaluate the migration of plutonium aerosol caused by α recoil. Methods In this paper, the recoil deposition and Brownian motion of plutonium-containing nanoaerosols were simulated by Monte Carlo method. The recoil angle and the vertical first landing time of Brownian motion in the process of settling were sampled, and then the lateral displacements of Brownian motion were sampled to determine the final settling position of aerosol. Results For aerosols with particle sizes of 10-50 nm, the maximum migration distance of a single recoil settling was 1.39 μm. Brownian motion increased the migration capacity. Although there was a high likelihood that aerosols settled within 100 μm, there remained a slight probability of long-term suspension in the air. Conclusion The α recoil is one of the mechanisms of plutonium aerosol migration. An important mechanism for long-distance migration of nanoaerosols is that Brownian motion after recoil may cause them to suspend for a long time.

Objective To determine the current situation of radiological health management in medical institutions in Nanyang, China, to analyze existing problems and propose improvement measures, and to improve the management level of radiological diagnosis and treatment practice in medical institutions. Methods According to the work plan of the Occupational Disease Prevention and Control Project in Henan Province, China, 66 medical institutions engaged in radiological diagnosis and treatment at different levels were selected for a questionnaire survey, in combination with on-site inspections, inquiries, and access to relevant materials. Results Of 66 medical institutions, 65 institutions held radiological diagnosis and treatment licenses, with a license holding rate of 98.5%. There were 17 “new construction, reconstruction, and expansion” projects, with an evaluation rate of 94.1%. In this survey, a total of 391 radiological diagnosis and treatment equipment were involved, and 387 units of equipment were tested for status, with a detection rate of 99.0% and a qualification rate of 94.8% (367/387); 55 units of equipment were tested for stability, with a detection rate of 14.1%; the workplace protection detection rate was 99.0%, and the qualification rate was 100%; 66 medical institutions had 1809 radiation workers, with an occupational health examination rate of 97.8%; 1262 people were trained, with a training rate of 95.7%; 1773 people were monitored for individual dose, with a monitoring rate of 98.0%. Conclusion Medical institutions should further strengthen management in licensing change, construction project evaluation, and equipment stability monitoring to improve the level of radiological health management.

Objective To investigate the awareness, implementation, and application of the Radiation Shielding Specification for Radiotherapy Room, Part 3: Radiotherapy Room of γ-Ray Sources (GBZ/T201.3—2014) by medical institution personnel, to collect problems and recommendations, and to provide a scientific basis for further amendments and implementation of the standard. Methods A questionnaire survey about the awareness, training and application situation and the modification advices of the standard was conducted among practitioners engaged in the production, use, and machine room design related to γ-ray source radiotherapy equipment (collectively referred to as medical institution personnel) in 12 provinces and direct-administered municipalities in China. The questionnaires were collected and a special Excel database was set up for statistical analysis using SPSS 22.0. Results A total of 126 practitioners responded and completed the questionnaire. Approximately 75.4% of respondents indicated that they either “understood” or “understood well” the standard; 42.86% received relevant training; 45.24% and 54.76% indicated that the standard “met” or “basically met” the requirements of detection of γ-ray radiotherapy equipment shielding or design of shielding room. The standard was highly evaluated for suitability. However, the awareness of the standard was inadequate, the rate of training participation was low, and its practical application was limited. Conclusion The standard generally aligns with the requirements for shielding room design in γ-ray radiotherapy. Some revisions should be done according to the current situation of γ-ray radiotherapy.

Objective To evaluate the value of dual-source CT angiography for evaluating the degree of coronary stenosis. Methods A total of 110 patients with a high likelihood of coronary stenosis identified by dual-source CT angiography or conventional coronary angiography were enrolled. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of dual-source CT angiography for diagnosis of coronary stenosis were evaluated with conventional coronary angiography as a gold standard. The agreement between dual-source CT angiography and conventional coronary angiography for evaluation of coronary stenosis was evaluated using Kappa statistic. Results A total of 1 401 coronary artery segments from 110 patients were displayed on conventional coronary angiography, while 1 382 segments were successfully visualized in dual-source CT angiography (98.64%). The sensitivity, specificity, positive predictive value and negative predictive value of dual-source CT angiography were 97.9%, 97.3%, 90.4% and 99.4% for diagnosis of coronary stenosis, and there was high consistence between dual-source CT angiography and conventional coronary angiography for grading coronary stenosis (Kappa statistic = 0.87, U = 58.36, P < 0.01). In addition, the sensitivity, specificity, positive predictive value, negative predictive value and accuracy of dual-source CT angiography were 94.7%, 96.8%, 83.7%, 99.0% and 96.5% for grading stenosis of coronary artery segments. Conclusion Dual-source CT angiography is accurate and reliable for diagnosis of coronary stenosis, which may be a non-invasive tool for assessment of coronary stenosis.

In 2003, the responsibility of radiation source safety supervision was redivided and transferred from the health department to the environmental protection department. After the promulgation and implementation of the Rule on the Administration of Radiodiagnosis and Radiotherapy in 2006, due to the incorporation of a large number of medical practice supervision rules, the radiation health supervision of medical institutions has evolved into the radiodiagnosis and radiotherapy supervision. In the past 16 years, radiation, occupational health supervision, and medical practice supervision have not been well integrated, and there are many legal problems in radiodiagnosis and radiotherapy supervision. The regulation rules of environmental protection, metrology, and other relevant departments on radiation sources and radiation devices have been constantly changing, resulting in overly complex regulatory requirements on radiodiagnosis and radiotherapy, which increases the burden of medical institutions. This paper reviews the historical evolution and legal system changes of radiodiagnosis and radiotherapy supervision, analyzes the problems and challenges faced by the relevant regulatory departments, and proposes ways to improve the supervision system.

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.