Objective: To investigate the current level of public awareness regarding nuclear emergency evacuation around a nuclear power plant, analyze the influencing factors, and propose suggestions and countermeasures based on the results. Methods: In July 2024, according to the survey protocol and questionnaire developed by the National Institute for Radiological Protection, Chinese Center for Disease Control and Prevention, a field-based centralized online questionnaire was administered. A total of 854 residents living near the nuclear power plant were included as survey participants. An analysis of variance was used to compare the impact of different factors on the public knowledge of nuclear radiation and awareness of nuclear emergency evacuation, while the chi-square test was employed to compare differences between groups. Results: A total of 854 questionnaires were collected in this study. The survey revealed that the levels of public knowledge about nuclear radiation and awareness of nuclear emergency evacuation around the power plant were relatively low, with average objective awareness rates of 51% and 47%, respectively. In terms of age, the 30-45 years old group had the highest average score, while the group aged 60 and above had the lowest. Regarding education level, the group with primary school education or below had the lowest average score, whereas those with junior college or undergraduate education scored the highest. The internet (73.7%) was the primary source of emergency information for the public, followed by television (61.7%). The majority of the public (85.0%) expressed trust in the government during evacuation and were willing to follow governmental evacuation arrangements. The main reason for this willingness was the belief that the government could provide sufficient emergency supplies. Conclusion: The surveyed population exhibited low levels of knowledge regarding nuclear radiation and awareness of nuclear emergency evacuation, with generally low awareness rates. Awareness levels were influenced by factors such as sex, age, educational background, and distance from the nuclear power plant. To enhance public awareness, it is necessary to strengthen science communication related to nuclear radiation and public protective actions in nuclear emergencies. Targeted dissemination strategies with high communication effectiveness, accessibility, and public acceptance should be adopted to gradually enhance public awareness of nuclear radiation and nuclear emergency protective actions.

Dose conversion coefficients connect radiation field quantities with the protection quantities and operational quantities. In radiation protection practice, it plays an important role in facilitating the conversion between various measurement values, enabling compliance with individual dose limits, and optimizing radiation protection strategies. During the conversion process, conversion coefficients are affected by the types of rays, irradiation geometries, and human tissues and organs. Notably, the continuous development of anthropomorphic digital phantoms has led to the constant updating of conversion coefficients and the broadening of their application fields. However, with the development of radiation protection theory, new challenges have emerged in the establishment of conversion coefficients. This paper provides a concise overview of these aspects, aiming to give readers a basic understanding of the significance, application, and challenges associated with the conversion coefficients. Such an understanding will facilitate the effective implementation of the newly released standard WS/T 830.

Objective: Emergency response to public health emergencies constitutes a vital component of the modernization of national governance systems and capacities, directly impacting national security, social stability, and public health. This study aims to analyze the key issues and research hotspots in the field of emergency response to public health emergencies, providing theoretical foundations and practical guidance for formulating scientific and effective emergency strategies and policies. Ultimately, it seeks to enhance the nation’s capability to respond to public health emergencies and safeguard public health. Methods: Using core journals indexed in the China National Knowledge Infrastructure (CNKI) database as the data source, 1094 journal articles in the field of emergency response to public health emergencies in China from 2003 to September 2024 were selected as the research sample. Citespace visualization software was employed to organize and analyze the research process in the field of emergency response to public health emergencies. Results: The current research in this field predominantly involves small-scale cooperation, and the research process can be divided into four stages. The research in the emerging stage mainly focuses on the themes of emergency mechanism and emergency management, the development stage mainly centers on the themes of emergency capacity improvement and system exploration, the outbreak stage emphasizes the themes of COVID-19 and epidemic prevention and control, and the sustainable development stage highlights collaborative governance and informatization. Conclusion: The COVID-19 pandemic has accelerated the development of research in this field. Currently, the field shows a continuous growth, with an increasing volume of publications. The focus of current research has shifted towards collaborative governance and the study of assessment tools, aiming to enhance the efficiency and effectiveness in responding to public health emergencies. Moreover, the field is advancing toward more systematic and comprehensive research. However, there is still a need to strengthen scientific communication and collaboration.

Objective: To explore and establish a technical pathway for size-specific dose estimate (SSDE) in pediatric CT patients of different age groups based on structured dose files and DICOM files, and to provide an effective method for precise monitoring of medical radiation exposure in pediatric CT scans. Methods: Structured radiation dose reports (SR files) for pediatric patients aged 15 and under, who underwent CT scans between January and December 2023, were exported from the hospital information system. Scanning parameters and dose information were extracted using specialized software, and SSDE was calculated based on the patient body size parameters. The data were grouped by age (0- < 1 year, 1- < 5 years, 5- < 10 years, and 10-15 years) for statistical analysis. Results: From January to December 2023, a total of 2706 pediatric CT scans were performed at the hospital, including 385 (14.23%) head scans, 1990 (73.54%) chest scans, 143 (5.28%) abdominal scans, 112 (4.14%) limb scans, and 76 (2.81%) other scans. The typical volume CT dose index (CTDI_vol) for head CT in the age groups of 0- < 1 year, 1- < 5 years, 5- < 10 years, and 10-15 years were 36.21, 35.29, 37.27, and 41.18 mGy, respectively; the corresponding SSDE values were 41.27, 32.82, 30.56, and 28.41 mGy, respectively. For chest CT scans, the typical CTDI_vol for the age groups of 1- < 5 years, 5- < 10 years, and 10-15 years were 1.91, 2.11, and 2.51 mGy, respectively; the corresponding SSDE values were 2.36, 2.21, and 3.50 mGy, respectively. For abdominal CT scans, the typical CTDI_vol for the age groups of 1- < 5 years, 5- < 10 years, and 10-15 years were 3.94, 4.33, and 6.26 mGy, respectively; the corresponding SSDE values were 5.77, 7.10, and 9.79 mGy, respectively. Conclusion: This study developed a technical pathway to estimate the medical radiation doses of pediatric CT patients of different ages based on structured dose files and DICOM files. The feasibility of this approach was validated using data collected over a one-year period.

Objective: To analyze the distribution characteristics and trends of occupational exposure types of medical radiation workers in Gansu Province, China, and to provide a basis for administrative departments to formulate and adjust radiation protection policies. Methods: According to the radiation health information platform, the data of occupational exposure types of radiation workers in Gansu Province from 2014 to 2023 were obtained. The proportions of occupational exposure types in each physical examination year was statistically analyzed. Results: From 2014 to 2023, the number of medical radiation workers accounted for more than 70% of the total number of radiation workers. The proportion of X-ray imaging diagnostic radiation workers in the total number of medical radiation workers gradually decreased but remained the highest, exceeding 68% annually. The proportion of interventional radiology workers in the total number of medical radiation workers increased from 13.8% to 25.5%. The proportions of radiation therapy and nuclear medicine workers in the total number of medical radiation workers increased slowly. The numbers of interventional radiology and radiotherapy workers in tertiary hospitals both accounted for more than 70% of the total number of such workers in the province. The proportion of interventional radiology workers increased and then decreased. The proportion of radiotherapy workers increased significantly from 70.5% to 93.0%. The number of nuclear medicine workers in tertiary hospitals accounted for more than 80% of such workers in the province. Conclusion: Radiation protection policies and measures should be adjusted according to the changes in the types of occupational exposure. The focus of these policies and measures should differ depending on the level of healthcare institutions, the type of radiological diagnostic and therapeutic services, and the characteristics of various occupational exposure types .

Objective: Based on the radiomics features extracted from the unenhanced CT images of the lower abdomen, a variety of machine learning models were constructed to explore their application value in the assessment of split renal function. Methods: A retrospective analysis was conducted on the unenhanced CT images from 240 single kidneys in patients with clinically suspected renal dysfunction. Based on the results of single-photon emission computed tomography renal dynamic imaging, the cases were classified into the normal glomerular filtration rate group (n=118) and the decreased glomerular filtration rate group (n=122). The region of interest was outlined on the unenhanced CT images and the radiomics features were extracted. The features were selected by correlation analysis and least absolute shrinkage and selection operator, and the machine learning models were constructed based on the algorithms of decision tree, support vector machine, random forest, logistic regression, and extreme gradient boosting. Area under the receiver operating characteristic curve, accuracy, sensitivity, and specificity were calculated to compare the performance of different models. Results: Sixteen radiomics features were selected for constructing the machine learning models. The support vector machine model showed relatively high performance for the assessment of split renal function on the test set, with an area under the receiver operating characteristic curve value of 0.883 (95% confidence interval: 0.804-0.961), an accuracy of 0.778, a sensitivity of 0.811, and a specificity of 0.743. Conclusion: The machine learning models constructed based on unenhanced CT radiomics can be used to preliminarily assess split renal function, which provides an innovative, convenient, and safe method for clinical diagnosis and has positive significance for treatment.

Objective: To explore the CT diagnosis and differential diagnosis of perivascular epithelioid cell neoplasms (PEComa), improve the accuracy of PEComa diagnosis, and reduce misdiagnosis. Methods: CT findings of 8 cases of PEComa confirmed by pathology in Jining First People’s Hospital from January 2020 to April 2024 were retrospectively analyzed for the location, shape, size, boundary, plain scan density, and enhancement characteristics of the lesions. Results: All 8 tumors were solitary, with 5 located in the kidney, 1 in the liver, 1 in the extraperitoneal space, and 1 in the retroperitoneal space. The tumors were round in 3 cases, oval in 1 case, and irregular in 4 cases. Seven cases were benign with clear boundaries and 1 case was malignant with unclear boundaries. On plain CT, 2 cases showed slightly low density, 3 cases showed slightly high density, and 3 cases showed low density. One tumor had uniform density, and 7 tumors had nonuniform density with internal necrosis and cystic changes. Contrast-enhanced CT revealed diverse enhancement patterns. Four cases showed a “fast in and fast out” enhancement pattern, with significant arterial-phase enhancement and reduced portal venous-phase enhancement. Three cases showed a “fast-in and slow-out” enhancement pattern, with significant enhancement in the arterial phase, persistent enhancement in the portal venous phase, and slightly reduced density in the delayed phase. One case showed mild enhancement in the arterial phase and significant enhancement in the portal venous phase. In 3 cases, multiple tortuous and thickened blood vessels were observed around the tumors, while 3 cases showed tortuous vascular shadows within the tumors. Conclusion: PEComa demonstrates characteristic CT features, predominantly with “fast in and fast out” or “fast in and slow out” enhancement patterns. When thickened and tortuous blood vessels are observed within or around the tumor, PEComa should be considered in combination with clinical findings.

Objective: To investigate the bone protective effects and underlying mechanisms of 900MHz radiofrequency radiation (RF) at different power densities (50, 150, and 450 μW/cm²) on an ovariectomy-induced osteoporosis mouse model. Methods: Sixty 3-month-old C57BL/6 female mice were randomly divided into Sham group (sham exposure), OVX group (ovariectomy), OVX + LRF group (OVX + 50 μW/cm² RF), OVX + MRF group (OVX + 150 μW/cm² RF), OVX + HRF group (OVX + 450 μW/cm² RF), and OVX + E2 group (OVX + estradiol). Ovariectomized mice in the OVX + RF groups were exposed to RF of varying power densities for 4 hours daily. Ovariectomized mice in the OVX + E2 group received intramuscular injections of estradiol (0.04 mg/kg) every two days. After four weeks of intervention, Micro-CT, ELISA, RT-PCR, and immunohistochemistry were employed to analyze bone density, bone microstructure, serum bone metabolic markers, and the expression of related genes and proteins. Results: Compared with the Sham group, the OVX group showed significantly decreased bone mineral density (BMD) and bone microstructure indicators such as BV, BV/TV, Tb.Th, and Tb.N, significantly increased bone microstructure indicator Tb.Sp, significantly decreased serum estradiol, significantly increased serum CTX-I, TRACP-5b, BGP, and OPG, significantly increased Nfatc1 and Runx2 mRNAs, and significantly increased OPG and RANKL. Compared with the OVX group, the OVX + MRF group and OVX + E2 group exhibited significantly increased BMD, BV, BV/TV, Tb.Th, and Tb.N, significantly decreased Tb.Sp, significantly increased serum OPG, Runx2 mRNA, and OPG, and significantly decreased serum CTX-I, TRACP-5b, Nfatc1 mRNA, and RANKL. Compared with the OVX group, the OVX + LRF group showed significantly increased cortical bone BMD and Tb.Th, the OVX + HRF group showed significantly increased cortical bone BMD and serum CTX-I and TRACP-5b, and the OVX + MRF group showed significantly increased serum BGP. Among the three power densities, the 150 μW/cm² RF showed the most significant effect. Conclusion: The 150 μw/cm² 900 MHz RF can counteract the abnormalities in serum bone metabolism biomarkers, the decrease in BMD, the degeneration of bone microstructure, and the increase in bone resorption caused by ovariectomy in mice.

Objective: To investigate the role and related mechanisms of exosomes derived from mesenchymal stem cells (MSCs) in radiation-induced lung injury (RILI). Methods: Human umbilical cord-derived MSCs were isolated and cultured for the extraction and identification of exosomes. Eighteen male SD rats were randomly divided into Control group, RILI group and RILI + exosomes group (EXO group), with 6 rats in each group. Except for Control group, the other groups received a single X-ray dose of 30 Gy to the right lung. Immediately after irradiation, the EXO group was administered 2 × 10⁹ exosomes/kg via tail vein injection. Control group and RILI group were given the same volume of normal saline. Eight weeks post-irradiation, the rats were sacrificed, lung tissue and peripheral venous blood were collected. HE and Masson staining were employed to observe the pathological and fibrotic changes of lung tissue. The levels of serum inflammatory factors IL-6, IFN-γ, TNF-α, and IL-10 were detected by ELISA. RT-qPCR was used to assess the mRNA levels of IL-1β, IL-6, Cdh1, and Col1a1 in lung tissue. The expression levels of Vimentin and TGF-β1 in lung tissue were measured by immunohistochemical staining. The expression levels of AMPK, p-AMPK, and TGF-β1 in lung tissue were detected by Western blot. Results: MSC-derived exosomes were successfully extracted and identified. Compared with RILI group, EXO group showed significantly reduced pathological changes of lung inflammation and collagen deposition. The levels of serum inflammatory factors IL-6, INF-γ, and TNF-α were significantly decreased (P < 0.05), and the level of anti-inflammatory factor IL-10 was significantly increased (P < 0.05). The mRNA levels of IL-1β, IL-6, and Col1a1 in lung tissue were significantly decreased (P < 0.05 or P < 0.01), and the mRNA level of Cdh1 was significantly increased (P < 0.05 or P < 0.01). The levels of Vimentin and TGF-β1 in lung tissue were significantly reduced, while p-AMPK level was significantly up-regulated (P < 0.05). Conclusion: Exosomes derived from MSCs may alleviate RILI by inhibiting inflammatory responses and regulating epithelial-mesenchymal transition mediated by AMPK/TGF-β1 signaling pathway.

Objective: To investigate and analyze the occupational stress levels and influencing factors among radiation workers in China, and provide a reference for alleviating occupational stress and promoting mental health. Methods: Using the general situation questionnaire, Effort-Reward Imbalance questionnaire, and radiation protection knowledge questionnaire, a convenience sampling method was adopted to investigate the occupational stress of 243 radiation workers in Liaoning, Fujian, Guangdong, and Xinjiang provinces. The independent samples t-test, one-way analysis of variance, chi-square test, and binary logistic regression were used to analyze the influencing factors. Results: The average score of Effort-Reward Imbalance was 0.97 ± 0.22, and 100 (41.15%) radiation workers had occupational stress. There were significant differences in the detection rate of occupational stress among radiation workers of different ages, working years in radiation positions, monthly incomes, daily sleep durations, and daily working hours (P < 0.05). Logistic regression analysis identified daily working hours as a factor contributing to occupational stress. Conclusion: The occupational stress among radiation workers in China is relatively severe. It is recommended to pay attention to the associated risks and implement targeted intervention measures to reduce the impact of occupational stress.

Objective: To establish a model of radiation-induced myocardial fibrosis in mice, and study the effect of TGF-β/SMAD pathway on radiation-induced myocardial fibrosis in mice and the protective effect of pirfenidone capsules (PFD) on radiation-induced myocardial fibrosis. Methods: Male C57BL/6J mice were randomly divided into control group, irradiation group, and drug intervention groups (low-dose PFD + irradiation group and high-dose PFD + irradiation group). After radiation exposure, the control group and the irradiation group were given sodium carboxymethyl cellulose by gavage, while the low-dose PFD + irradiation group and the high-dose PFD + irradiation group were given PFD at 150 and 300 mg/kg daily by gavage for 12 consecutive weeks, respectively. The body weights of mice were measured and recorded weekly. The pathological changes of heart tissues in mice were observed by H&E and Masson’s trichrome staining. The expression levels of TGF-β, SMAD2, and SMAD3 mRNAs in mouse heart tissues were detected by RT-PCR. The expression levels of TGF-β, SMAD2, and SMAD3 proteins in mouse heart tissues were detected by Western blot. The expression levels of CK and CK-MB in mouse heart tissues were detected by blood biochemical tests. Results: H&E and Masson’s trichrome staining showed severe myocardial fibrosis in the irradiation group compared with the control group. Compared with the irradiation group, the two groups with drug intervention showed reduced heart disease and myocardial fibrosis. RT-PCR and Western blot showed that the expression levels of TGF-β, SMAD2, and SMAD3 were up-regulated in the irradiation group compared with the other three groups (P < 0.05). The expression levels of TGF-β, SMAD2, and SMAD3 were down-regulated in the two groups treated with PFD compared with the irradiation group (P < 0.05). The expression levels of CK and CK-MB in mouse heart tissues were down-regulated in the two groups treated with PFD compared to irradiation group (P < 0.05). Conclusion: Radiation has long-term effects on normal heart tissue, causing myocardial damage and promoting myocardial fibrosis. The up-regulation of TGF-β/SMAD pathway is related to the formation of radiation-induced myocardial fibrosis. PFD can mitigate the progression of myocardial fibrosis and protect heart tissue by down-regulating TGF-β/SMAD pathway.

Objective: To verify the accuracy of γ spectrometry by analyzing the results of national interlaboratory comparisons of radionuclide analysis by γ spectrometry from 2018 to 2023. Methods: A statistical analysis was conducted on the results from multiple years of participation in the national interlaboratory comparisons of radionuclide analysis by γ spectrometry. The measurement results of radionuclide specific activities in soil were analyzed to provide technical support for improving the capability to analyze radionuclides in soil. Results: The laboratory participated in six interlaboratory comparisons and conducted 23 radionuclide analyses by γ spectrometry from 2018 to 2023. The relative deviation was −12.20% to 8.11%, the |Z_test| was 0 to 0.61, the U_test was 0 to 0.62, and the U_rel was 0.07 to 0.12. The overall pass rate was 100% and the excellent rate was 33.3%. In addition, 21 of the 23 (91.3%) radionuclide analyses showed full scores in experiment operation. However, the total scores were relatively low due to multiple oversights and lack of rigor in the preparation of the test reports, which prevented the laboratory from qualifying for the excellence evaluation process, resulting in a relatively low excellent rate. Conclusion: The interlaboratory comparisons indicate that the measurements of radionuclides in this laboratory were all qualified, with full scores for experiment operation in several analyses. These results demonstrate that the soil radionuclide analysis system based on γ spectrometry is reliable and stable.

⁶³Ni is predominantly generated through neutron activation in nuclear reactors and is classified as a pure beta-emitting radionuclide with a half-life of 101.1 a. During decay, ⁶³Ni emits a beta ray with an energy of 65.87 keV. ⁶³Ni can be used in the manufacture of beta radiation sources, which are utilized as reference and working sources for beta activity measurement and beta energy response calibration. Additionally, it is used in electron capture detectors for chromatography, ionization sources in electron tubes, and electron capture probes in gas chromatography. These instruments have extensive applications in food safety, public health and epidemic prevention, soil pollution monitoring, and security. ⁶³Ni is an artificial radionuclide not commonly found in the natural environment under normal conditions. However, the ⁶³Ni generated during routine operations of nuclear power plants, as well as residual materials and wastes contaminated with ⁶³Ni during plant decommissioning, may be released into the environment through liquid effluents or solid wastes. This can pose potential radiation risks to both the public and the environment. Hence, it is necessary to monitor the activity concentration of ⁶³Ni. Currently, reports on this subject are limited in China, and there is a lack of established standards for the determination of ⁶³Ni in nuclear power plants. This article reviews the global literature on the pretreatment and purification measurement processes of ⁶³Ni. The merits and demerits are summarized for pretreatment methods such as acid leaching, mixed acid digestion, ashing acid leaching/dissolution, and alkali fusion, and for separation and purification methods like solvent extraction, precipitation, and extraction chromatography. The article also highlights the advantages of measurement using liquid scintillation counters. This review provides a reference for the establishment of the determination method of ⁶³Ni in liquid effluents and solid wastes from nuclear power plants.

Objective: To assess and understand the service capabilities and existing problems of radiation health technical service institutions in Jiangsu Province, China, and provide a basis for improving in-process and post-process supervision as well as enhancing radiation health technical service capabilities. Methods: Thirty radiation health technical service institutions in Jiangsu Province were selected as quality monitoring objects from the National Occupational Health Technical Service Institution Management Information System. Evaluations were conducted using a standardized national assessment checklist, and a comprehensive risk assessment was performed by combining the results of laboratory test capability comparisons. Results: The 30 institutions all passed the quality monitoring, with an average score of （76.62 ± 5.07）. Comprehensive risk assessment identified 8 (26.67%) high-risk institutions, 22 (73.33%) medium-risk institutions, and 0 (0%) low-risk institutions. Conclusion: The overall service quality of radiation health technical service institutions in Jiangsu Province is acceptable. However, further training and supervision are needed to improve technical service capacity and reduce service risks.

With the rapid development of interventional radiology technology, the occupational health risk of interventional radiation workers has attracted increasing attention. This paper reviews recent studies on hematological changes, DNA damage and molecular-level changes, cancer, eye lens, and other health impairments among interventional radiation workers. The aim is to provide an overview of the current research progress as well as a scientific basis for the implementation of targeted protective measures to improve the occupational health level of interventional radiology workers.

Objective: To observe changes in genetic material in the peripheral blood of pediatric patients with vascular malformations after interventional procedures. Methods: A total of 108 children with vascular malformations who underwent interventional procedures at Shandong University Affiliated Children’s Hospital between February 2021 and January 2024 were selected as the research subjects. Clinical data and peripheral venous blood samples before and after the interventional procedures were collected from the children. Two biological indicators, γ-H2AX and peripheral blood lymphocyte chromosomal aberration (CA), were used to determine the levels of genetic material damage in children with vascular malformations before and after interventional procedures. Results: The median age of the children was 7 years and the median body weight was 27 kg. The median dose-area product (DAP) was 24.20 Gy·cm² and the median DAP/kg was 1.04 Gy·cm²/kg. The incidence rates of both γ-H2AX foci and CA in children with vascular malformations significantly increased after the interventional procedures (Z = 5.924, P < 0.001; Z = 8.515, P < 0.001). The incidence of postoperative CA in 7 children were significantly higher than that in others, approaching or exceeding 4%. The incidence rates of postoperative γ-H2AX foci and CA in children with DAP/kg ≥ 1 Gy·cm²/kg were significantly higher than those in children with DAP/kg < 1 Gy·cm²/kg (U = 7.586, P = 0.031; U = 6.835, P = 0.009). No significant differences were observed in the incidence rates of postoperative γ-H2AX foci and CA among subgroups based on age, body weight, or surgical site. A positive correlation was observed between the difference in the incidence rates of γ-H2AX foci before and after the procedure and DAP/kg (R = 0.493, P = 0.027). Conclusion: Ionizing radiation exposure during interventional procedures can increase peripheral blood genetic material damage levels in children with vascular malformations, and the damage levels show a correlation with the radiation dose, with some children being abnormally sensitive. Further research is needed to explore the influencing factors for genetic material damage in children with vascular malformations after interventional procedures, which is of great significance for reducing long-term cancer risks and achieving personalized treatment strategies.

Objective: To assess the clinical value of multimodal ultrasound score for assessment of endometrial receptivity among patients with polycystic ovary syndrome (PCOS), and to provide guidance for improving pregnancy outcomes among PCOS patients. Methods: A total of 48 PCOS patients admitted to Jiangning Hospital Affiliated to Nanjing Medical University between January and December 2023 were enrolled as the case group, while 50 healthy women of childbearing age received ovulation monitoring at the same hospital during the same period served as the control group. Subjects received two-dimensional grayscale ultrasound during the implantation window (19 to 23 days of the menstrual cycle) for measurement of endometrial thickness, Gonen classification, and endometrial peristalsis. Two-dimensional color Doppler ultrasound was used for assessment of endometrial blood flow and three-dimensional ultrasound was used for assessment of endometrial volume and vascularization flow index (VFI). The endometrium multimodal ultrasound scores were estimated, and various parameters were compared between the two groups. The diagnostic performance of these parameters for PCOS was evaluated with receiver operating characteristic (ROC) curves. Results: The age of subjects in the case group ranged from 20 to 38 years, with a mean age of (28.20 ± 2.82) years, and their body mass index (BMI) ranged from 21.23 to 29.11 kg/m², with a mean BMI of (26.25 ± 1.60) kg/m². The age of subjects in the control group ranged from 22 to 38 years, with a mean age of (28.10 ± 1.99) years, and their BMI ranged from 21.33 to 29.03 kg/m², with a mean BMI of (26.10 ± 1.78) kg/m². There were no significant differences between the case and control groups in terms of mean age, BMI, estradiol, and testosterone (t = 0.218, 0.422, 0.010, and 0.221; all P > 0.05). The endometrial thickness, endometrial volume, and VFI were significantly higher in the control group than in the case group (t = 4.838, 4.978, and 7.115; all P < 0.05). There were significant differences between the two groups in terms of endometrial classification, endometrial peristalsis pattern, and endometrial and sub-endometrial blood flow (Z = −4.136, −4.048, and −3.884; all P < 0.05). The scores of endometrial classification, endometrial peristalsis, endometrial and sub-endometrial blood flow, endometrial volume, VFI, and multimodal ultrasound were significantly lower in the case group than in the control group (t = 4.539, 4.449, 4.205, 3.209, 5.206, and 4.495; all P < 0.05). No significant difference was detected in the endometrial thickness score between the two groups (t = -0.149, P = 0.882). The areas under the ROC curves for endometrial thickness, endometrial volume, VFI, and multimodal ultrasound scores in diagnosis of PCOS were 0.753, 0.747, 0.809, and 0.858, respectively. Conclusion: Multimodal ultrasound score provides a comprehensive assessment of the endometrium, and is effective in the assessment of endometrial receptivity, which may provide a reference for guiding pregnancy planning in PCOS patients.

Mobile computed tomography (CT) can be used for critically ill patients’ bedside CT scans in an operating room or intensive care unit because of its flexibility and convenience compared to conventional CT. Meanwhile, attention has been paid to the ionizing radiation hazards brought by mobile CT scans due to a lack of wall shielding protection from a fixed machinery room, especially the control of radiation dose to the surrounding medical staff and the public. This article mainly discusses the radiation protection of mobile CT from aspects such as radiation protection principles, protection management, and protection of examinees, staff, and the public by summarizing relevant standards, guidelines, and literature in China and globally to provide a reference for the standardized use of mobile CT.

Objective: To understand the situation of dental cone beam computed tomography (CBCT) quality control testing phantoms in radiation health technical service institutions in Guangdong province, analyze the differences among different phantoms, and provide a reference for dental CBCT quality control testing. Methods: The testing phantoms of 49 radiation health technical service institutions were used as the research objects. The designated CBCT equipment was used for scanning and imaging. The Z-score method was used to evaluate the high-contrast resolution, low-contrast resolution, and distance measurement deviation of each phantom. Results: The satisfaction rates of various items for the phantoms in 49 institutions ranged from 85.7% to 100%. The distance measurement deviations of four institutions were “suspicious”, and the high-contrast resolution of four institutions and the distance measurement deviation of one institution were “unsatisfactory”. Conclusion: The overall performance of dental CBCT quality control testing phantoms in radiological health technical service institutions in Guangdong province is satisfactory. However, there are still some phantoms with poor results in items such as distance measurement deviation and high-contrast resolution. The structural design, material selection, and manufacturing process of the phantom may all affect the results of quality control testing. Therefore, appropriate phantoms, optimized exposure conditions, and suitable reconstruction algorithms should be used in CBCT quality control testing to ensure accurate and reliable measurements.