Objective To investigate the radon activity concentrations in subways of Nanning City and assess the average annual effective doses for subway staff and passengers due to radon exposure. Methods Sixty-three stations across the subway lines 2, 3, and 5 were selected as study sites. Radon activity concentrations were measured using the scintillation counting method with scintillation vials. Results The radon activity concentrations in subway lines 2, 3, and 5 were 7.9-24.4, 12.0-26.2, and 12.6-18.2 Bq/m³, respectively. The average radon activity concentrations for these three lines were (17.4 ± 4.6), (19.1 ± 4.1), and (14.6 ± 1.7) Bq/m³, respectively. Statistical analysis using SPSS 26.0 software revealed a significant difference in radon activity concentrations among these stations (P<0.01). Considering the data in previous research, the average radon activity concentration across all stations in the subway lines of Nanning City was determined to be 17.4 Bq/m³. The estimated average annual effective dose due to radon exposure was 0.131 mSv for subway staff and 0.033 mSv for passengers. Conclusion The radon activity concentrations in the subway lines of Nanning City were significantly lower than the national standard limit (400 Bq/m³). The annual effective doses from radon exposure for both subway staff and passengers were below the limits specified in the Basic Standards for Protection Against Ionizing Radiation and for the Safety of Radiation Sources (GB18871—2002). The health impact of radon and its progeny on subway staff and passengers in the subway lines of Nanning City was extremely low and can be considered negligible.

Objective:Using methylation characteristics of human genes to construct machine learning predictive models for screening cervical cancer and precancerous lesions.Methods:Human DNA methylation detection was performed on 224 cervical exfoliated cell specimens from the Cancer Hospital of the Chinese Academy of Medical Sciences, Tianjin Central Hospital of Gynecology Obstetrics, Xinmi Maternal and Child Health Hospital of Henan Province, West China Second Affiliated Hospital of Sichuan University, and Heping Hospital Affiliated to Changzhi Medical College collected during April 2014 and March 2015. The hypermethylated gene fragments related to cervical cancer were selected by high-density, high-association, and hypermethylated gene fragment screening and the LASSO regression algorithm. Taking cervical intraepithelial neoplasia grade 2 (CIN2) or more severe lesions as the research outcome, machine learning predictive models based on the random forest (RF), naive Bayes (NB), and support vector machine (SVM) algorithm, respectively, were constructed. A total of 144 outpatient specimens were used as the training set and 80 cervical exfoliated cell specimens from women participating in the cervical cancer screening program were used as the test set to verify the predictive models. Using histological diagnosis results as the gold standard, the detection efficacy for CIN2 or more severe lesions of the three machine learning predictive models were compared with that of the human papilloma virus (HPV) detection and cytological diagnosis.Results:In the training set of 144 cases, there were 34 cases of HPV positivity, with a positive rate of 23.61%. Cytologically, there were 37 cases diagnosed as no intraepithelial lesion or malignancy (NILM), and 107 cases diagnosed as atypical squamous cells of undetermined significance (ASC-US) or above. Histologically, there were 28 cases without cervical intraepithelial neoplasia or benign cervical lesions, 31 cases of CIN1, 18 cases of CIN2, 31 cases of CIN3, and 36 cases of squamous cell carcinoma. Seven hypermethylated gene fragments were selected from 45 genes, and three machine learning prediction models based on the RF, NB, and SVM algorithm, respectively, were constructed. In the validation set of 80 cases, there were 28 cases of HPV positivity, with a positive rate of 35.00%. Cytologically, there were 65 cases diagnosed as NILM and 15 cases as ASC-US or above. Histologically, there were 39 cases without cervical intraepithelial neoplasia or benign cervical lesions, 10 cases of CIN1, 10 cases of CIN2, 11 cases of CIN3, and 10 cases of squamous cell carcinoma. In the validation set, the area under the curve (AUC) values of the RF model, NB model, SVM model, HPV detection, and cytological diagnosis of CIN2 or above were 0.90, 0.88, 0.82, 0.68, and 0.45, respectively. The DeLong test showed that there was no statistically significant difference in the AUC values between the RF, NB, and SVM models (all P＞0.05), and the AUC values of the RF and NB models were higher than that of HPV detection (both P＜0.01), and the AUC values of the RF, NB, and SVM models were higher than that of cytological diagnosis (all P＜0.01). Compared with the NB model, the sensitivity of the RF model was similar (80.65% vs. 77.42%), but the specificity of the NB model was much higher than that of the RF model (93.88% vs. 73.47%). Conclusion:Among the machine learning prediction models for cervical cancer and precancerous lesions constructed based on human DNA methylation, the NB model has good predictive performance for CIN2 and above lesions, and may be used for screening of cervical cancer and precancerous lesions.

Objective:To develop outcome indicators for the implementation of comprehensive inter-ventions targeting the multimorbidity of myopia and obesity in children and adolescents,providing a basis for the co-prevention of multimorbidity and the outcome measurement of implementation research in children and adolescents.Methods:Based on the RE-AIM framework,a preliminary set of indicators was constructed.The Delphi method was employed,with experts scoring and providing feedback on the proposed indicators via questionnaires.After each round of consultation,expert enthusiasm index,authority coefficient,coordination degree,and consensus level were calculated.Expert opinions were col-lected and analyzed to modify,delete,or add indicators based on consultation results and screening crite-ria.Two Delphi rounds were conducted until consensus was achieved.Results:A total of 28 experts par-ticipated actually in both rounds.The Kendall's W coefficients for the two rounds of expert consultation were0.352(x2=413.952,P＜0.001)and 0.499(x2=405.044,P＜0.001),both statistically sig-nificant.The final outcome indicators for implementation research on comprehensive interventions for myopia and obesity comorbidity in children and adolescents included five primary dimensions with 13 secondary and 20 tertiary indicators.The dimension of reach included the number of children and adoles-cents involved,participant representativeness,and full-course participation representativeness.The di-mension of effectiveness included multimorbidity incidence,myopia incidence,spherical equivalent,body mass index(BMI),overweight and obesity prevalence,waist-to-height ratio,comprehensive health knowledge score,and comprehensive health behavior score.The dimension of adoption covered school representativeness and representativeness of school nurses and teachers involved in implementation.The dimension of implementation included fidelity,content modification,and cost.The dimension of mainte-nance included individual health outcomes and organizational sustainment.Conclusion:This study developed implementation outcome indicators for comprehensive interventions targeting multimorbidity of myopia and obesity among the children and adolescents based on the RE-AIM framework.These indica-tors can serve as a reference for optimizing intervention research strategies related to common multimor-bidity among children and adolescents in China.

BACKGROUND:Slow bone repair and poor bone formation quality are still problems during masquelet technique in the treatment of large segment bone defects.H-type vessels can induce osteogenesis,enhance the local angiogenesis and osteogenesis coupling,and promote bone repair.However,there are few reports on the role of H-type blood vessels in the bone induced membrane.OBJECTIVE:To construct a large segment bone defect model of SD rat tibia,observe the expression characteristics of H-type blood vessels in the bone induced membrane,then to identify the expression peak point of H-type blood vessels in the bone induced membrane and determine the optimal period of bone grafting.METHODS:Sixty SD rats were randomly divided into a control group(n=30)and a model group(n=30)by random number table method.The two groups were further divided into three subgroups at 4,6,and 8 weeks after bone cement implantation,with 10 rats in each group.A 4 mm bone defect model of the right tibia was constructed in both the control and the model groups.Polymethyl methacrylate bone cement was implanted in the model group to induce bone biomembrane formation,while bone cement was not implanted in the control group.At 4,6,and 8 weeks after bone cement implantation,6 rats were randomly selected at each time point.The bone induction membrane tissue was cut from the model group,and the non-bone soft tissue of the corresponding part was cut from the control group.The dynamic expressions of H-type blood vessels in the bone induced membrane were identified by immunofluorescence.The morphological changes of the bone induced membrane were observed by hematoxylin-eosin staining.The formation of blood vessels in the bone induced membrane was observed by angiography.The expression levels of osteoblast-specific transcription factor in the bone induced membrane were detected by immunohistochemistry.Four rats remained at each time point.In the model group,the bone induced membrane was cut open and the bone cement was removed and autologous coccyx was implanted.In the control group,autologous coccyx was implanted in the bone defect area.Micro-CT evaluation of the tibial defect was performed 8 weeks after bone grafting.RESULTS AND CONCLUSION:(1)Immunofluorescence staining showed that the expression of H-type vessels in the model group was most obvious 6 weeks after bone cement implantation,and the expression of H-type vessels in the model group at each time point after bone cement implantation was higher than that in the control group(P＜0.05).(2)Hematoxylin-eosin staining and angiography showed that the number and volume of new blood vessels at each time point after bone cement implantation in the model group were greater than those in the control group(P＜0.05).The order of the number and volume of new blood vessels in the model group was:8 weeks after bone cement implantation＞6 weeks after bone cement implantation＞4 weeks after bone cement implantation.(3)Immunohistochemical staining showed that the positive expression of osteoblast-specific transcription factors at each time point after bone cement implantation in the model group was higher than that in the control group(P＜0.05),and the positive expression of osteoblast-specific transcription factors in the model group was most obvious 6 weeks after bone cement implantation.(4)Micro-CT detection showed that the bone repair effect of the three subgroups in the model group was significantly better than that of the corresponding subgroups in the control group,and the bone repair effect of the subgroup in the model group 6 weeks after bone cement implantation was better than that of the subgroups 4 and 8 weeks after bone cement implantation.The results indicate that H-type blood vessels are dynamically expressed in the bone induced membrane and reached a peak 6 weeks after bone cement implantation.Good bone repair effects can be obtained by the bone induced membrane bone grafting 6 weeks after bone cement implantation.

Objective: To explore the association between mental health and muscle strength among Chinese adolescents aged 13- 18, providing a theoretical foundation and intervention strategies for mental health promotion. Methods: Data were obtained from the 2019 Chinese National Survey on Students Constitution and Health, including 98 631 Chinese adolescents aged 13- 18. Psychological distress was assessed by using the Kessler Psychological Distress Scale (K10), and mental well being was measured with the Warwick-Edinburgh Mental Well being Scale (WEMWBS). Based on the gender and age specific Z scores of various test items [grip strength, standing long jump, pull ups (for males), and sit ups (for females)], muscle strength index (MSI) was constructed to evaluate the comprehensive level of muscle strength in adolescents. According to the Dual factor Model (DFM) of mental health, participants were categorized into four groups:troubled, symptomatic but content, vulnerable, and complete mental health. Gender differences were analyzed by using Chi-square tests, trends were tested with Cochran-Armitage tests, and multinomial Logistic regression models were applied to assess associations between muscle strength and mental health among adolescents. Results: In 2019, 37.4% of Chinese adolescents aged 13-18 were reported of high mental distress, and 59.9% were reported of low mental well being. Boys had significantly lower rates of high mental distress (35.3%) and low mental well being (55.6%) compared to girls (39.4%, 64.3%), and the differences were of statistical significance ( χ 2=176.13, 780.42, both P <0.05). In 2019, the rate of complete mental health among adolescents showed a downward trend with increasing age ( χ 2 trend = 258.47) and a gradual upward trend with increasing muscle strength levels ( χ 2 trend =123.14)，and both boys and girls exhibited similar trends ( χ 2 trend =103.83, 168.46; 57.00 , 67.34) (all P <0.05). The results of the unordered multiclass Logistic regression model showed that after controlling for confounding factors such as age and gender, when the completely pathological group as a reference, for every 1 unit increase in MSI in adolescents, the likelihood of being in a completely mental health state increased by 29% ( OR = 1.29); for every unit increase in the Z-score for pull ups, the likelihood of being in a completely mental health state increased by 6% ( OR =1.06) among boys; for every 1 unit increase in sit up Z score, the likelihood of being in a completely mental health state increased by 19% ( OR =1.19) among girls (all P <0.05). Conclusions The mental health status of Chinese adolescents is not good enough. Muscle strength is positively associated with mental health.

Objective: To systematically review the development and changes in mental health policies within the National Outline for Children s Development in China from 1992 to 2030, providing a reference basis for future formulation of mental health policies among children and adolescent in China. Methods: Based on the four editions of the National Outline for Children s Development in China across different periods from 1992 to 2030, word frequency analysis was used to reveal shifts in policy priorities, and an internationally recognized framework for adolescent health policy analysis was applied to conduct a textual review. Results: Word frequency analysis revealed that the term "psychological" appeared 6 times in the National Outline for Children s Development in China (2001-2010) but increased to 20 times in the National Outline for Children s Development in China (2021-2030) (abbreviated as the National Outline of 2021), while the term "health" rose from 4 times in the National Outline for Children s Development Plan in China in the 1990s to 68 times in the National Outline of 2021. The scope of mental health policy interventions expanded to encompass five key areas:health, safety, education, welfare and legal protection. Textual analysis highlighted that the policies of the National Outline for Children s Development in China were demand driven, prioritized vulnerable groups and continuously broadened their coverage, emphasizing sustainability and appropriateness, and monitoring/evaluation mechanisms. By 2023, 42.3% of primary schools and 64.8% of secondary schools employed full time mental health education teachers. However, the National Outline for Children s Development in China lacked direct evidence of children and adolescents participation in policy formulation, and publicly available mental health data disaggregated by age and gender remained limited. Conclusion Mental health policies of children and adolescents in China have evolved from nonexistence to gradual refinement, yet institutionalized channels for youth involvement in policy development and evaluation remain insufficient, and transparency in age and gender specific mental health data needs improvement.

Objective:To analyze the changes in the prevalence characteristics of multimorbidity among adolescents aged 13-18 in Inner Mongolia Autonomous Region from 2019 to 2022 and to explore the association between multimorbidity and moderate to high-intensity physical activity among them.Methods:A stratified random cluster sampling method was used to select students aged 13-18 in Inner Mongolia Autonomous Region every September from 2019 to 2022. Physical examinations, demographic characteristics, and depression-related surveys were conducted to analyze the multimorbidity of overweight, obesity, high blood pressure, myopia, spinal curvature abnormality, and depression. A logistic regression model was used to analyze the association between multimorbidity and moderate to high-intensity physical activity.Results:From 2019 to 2022, 70 972, 62 923, 80 254, and 78 288 study subjects were included, with the rates of multimorbidity being 56.4%, 55.4%, 57.2%, and 55.8%, respectively. The rates of multimorbidity remained relatively stable from 2019 to 2022 ( χ2=0.06, P=0.950). The incidence of multimorbidity among girls was significantly higher than that among boys ( P<0.001). The incidence of multimorbidity among urban students was significantly higher than that among suburban students ( P<0.001). The incidence of multimorbidity among high school students was higher than that among middle school students ( P<0.001). The top three multimorbidity combinations were myopia and overweight/obesity (26.4%), myopia and high blood pressure (24.4%), and myopia and depression (19.8%), while the least common combination was depression and spinal curvature abnormality (1.1%). The multimorbidity patterns showed no significant differences between years ( χ2=0.03, P=0.999). The multimorbidity status was significantly associated with the status of meeting the standard of moderate to high-intensity physical activity ( OR=0.83, 95% CI: 0.80-0.86). The association was stronger in boys ( OR=0.77, 95% CI: 0.73-0.81) compared with girls ( OR=0.90, 95% CI: 0.85-0.96), with a significant interaction term ( P<0.001). Conclusion:From 2019 to 2022, the incidence of multimorbidity among adolescents aged 13 to 18 in Inner Mongolia Autonomous Region is relatively high, mainly due to the co-occurrence of myopia and other health problems. Adequate physical activity is an important factor in reducing multimorbidity.

Objective:To construct analytical dimensions for policy texts related to the pilot work of Health Impact Assessment (HIA) system in Zhejiang Province and conduct quantitative analysis, thereby providing references for improving the pilot work.Methods:Policy texts issued by Zhejiang Province between February 11, 2018, and February 29, 2024, which involved HIA content, were selected. The policy instruments theory was employed to construct an analytical framework around the dimensions of policy instruments, policy objectives, policy actors, and the interactions between policy instruments and policy objectives, and between policy instruments and policy actors. Based on this framework, a combination of literature analysis and content analysis was used to conduct a multi-dimensional quantitative analysis of the policy texts related to the pilot work of HIA system in Zhejiang Province.Results:Fifty core policy texts were included and 1 588 codes were obtained. In terms of policy instruments, environmental-type instruments were the most widely used (852 items), with internal responsibilities and methodological measures being the most frequently used; supply-type instruments were the second most used (459 items), with mechanism improvement being the most frequently used; demand-type instruments were the least used (277 items), with multi-stakeholder participation being the most frequently used. In terms of policy objectives, the objective of system construction dominated (701 articles, accounting for 56.45%), while the proportion of policy coverage, evaluation technology, and effectiveness evaluation was relatively low. In terms of policy subjects, the Party committee and government were the main policy subjects (434 articles, accounting for 39.20%), followed by health departments and public policy-making departments, while the proportion of public health institutions and social forces was extremely low. In the interaction between policy instruments and policy objectives, policy coverage, system construction, and effectiveness evaluation objectives all responded most frequently to environmental-type instruments, while the evaluation technology objectives responded more frequently to supply-type instruments. In the interaction between policy instruments and policy subjects, the Party committee and government played a dominant role in the use of policy instruments, with the health department and public policy-making department in the middle.Conclusions:The pilot work of the HIA system in Zhejiang Province presented a " environment-driven, system-construction-priority, Party-committee-and-government-led" policy characteristic. The main challenges were the imbalanced structure of policy instruments, insufficient synergy among policy objectives, and the need for greater participation of multiple stakeholders.

Objective:To analyze the changes in the prevalence characteristics of multimorbidity among adolescents aged 13-18 in Inner Mongolia Autonomous Region from 2019 to 2022 and to explore the association between multimorbidity and moderate to high-intensity physical activity among them.Methods:A stratified random cluster sampling method was used to select students aged 13-18 in Inner Mongolia Autonomous Region every September from 2019 to 2022. Physical examinations, demographic characteristics, and depression-related surveys were conducted to analyze the multimorbidity of overweight, obesity, high blood pressure, myopia, spinal curvature abnormality, and depression. A logistic regression model was used to analyze the association between multimorbidity and moderate to high-intensity physical activity.Results:From 2019 to 2022, 70 972, 62 923, 80 254, and 78 288 study subjects were included, with the rates of multimorbidity being 56.4%, 55.4%, 57.2%, and 55.8%, respectively. The rates of multimorbidity remained relatively stable from 2019 to 2022 ( χ2=0.06, P=0.950). The incidence of multimorbidity among girls was significantly higher than that among boys ( P<0.001). The incidence of multimorbidity among urban students was significantly higher than that among suburban students ( P<0.001). The incidence of multimorbidity among high school students was higher than that among middle school students ( P<0.001). The top three multimorbidity combinations were myopia and overweight/obesity (26.4%), myopia and high blood pressure (24.4%), and myopia and depression (19.8%), while the least common combination was depression and spinal curvature abnormality (1.1%). The multimorbidity patterns showed no significant differences between years ( χ2=0.03, P=0.999). The multimorbidity status was significantly associated with the status of meeting the standard of moderate to high-intensity physical activity ( OR=0.83, 95% CI: 0.80-0.86). The association was stronger in boys ( OR=0.77, 95% CI: 0.73-0.81) compared with girls ( OR=0.90, 95% CI: 0.85-0.96), with a significant interaction term ( P<0.001). Conclusion:From 2019 to 2022, the incidence of multimorbidity among adolescents aged 13 to 18 in Inner Mongolia Autonomous Region is relatively high, mainly due to the co-occurrence of myopia and other health problems. Adequate physical activity is an important factor in reducing multimorbidity.

BACKGROUND:Slow bone repair and poor bone formation quality are still problems during masquelet technique in the treatment of large segment bone defects.H-type vessels can induce osteogenesis,enhance the local angiogenesis and osteogenesis coupling,and promote bone repair.However,there are few reports on the role of H-type blood vessels in the bone induced membrane.OBJECTIVE:To construct a large segment bone defect model of SD rat tibia,observe the expression characteristics of H-type blood vessels in the bone induced membrane,then to identify the expression peak point of H-type blood vessels in the bone induced membrane and determine the optimal period of bone grafting.METHODS:Sixty SD rats were randomly divided into a control group(n=30)and a model group(n=30)by random number table method.The two groups were further divided into three subgroups at 4,6,and 8 weeks after bone cement implantation,with 10 rats in each group.A 4 mm bone defect model of the right tibia was constructed in both the control and the model groups.Polymethyl methacrylate bone cement was implanted in the model group to induce bone biomembrane formation,while bone cement was not implanted in the control group.At 4,6,and 8 weeks after bone cement implantation,6 rats were randomly selected at each time point.The bone induction membrane tissue was cut from the model group,and the non-bone soft tissue of the corresponding part was cut from the control group.The dynamic expressions of H-type blood vessels in the bone induced membrane were identified by immunofluorescence.The morphological changes of the bone induced membrane were observed by hematoxylin-eosin staining.The formation of blood vessels in the bone induced membrane was observed by angiography.The expression levels of osteoblast-specific transcription factor in the bone induced membrane were detected by immunohistochemistry.Four rats remained at each time point.In the model group,the bone induced membrane was cut open and the bone cement was removed and autologous coccyx was implanted.In the control group,autologous coccyx was implanted in the bone defect area.Micro-CT evaluation of the tibial defect was performed 8 weeks after bone grafting.RESULTS AND CONCLUSION:(1)Immunofluorescence staining showed that the expression of H-type vessels in the model group was most obvious 6 weeks after bone cement implantation,and the expression of H-type vessels in the model group at each time point after bone cement implantation was higher than that in the control group(P＜0.05).(2)Hematoxylin-eosin staining and angiography showed that the number and volume of new blood vessels at each time point after bone cement implantation in the model group were greater than those in the control group(P＜0.05).The order of the number and volume of new blood vessels in the model group was:8 weeks after bone cement implantation＞6 weeks after bone cement implantation＞4 weeks after bone cement implantation.(3)Immunohistochemical staining showed that the positive expression of osteoblast-specific transcription factors at each time point after bone cement implantation in the model group was higher than that in the control group(P＜0.05),and the positive expression of osteoblast-specific transcription factors in the model group was most obvious 6 weeks after bone cement implantation.(4)Micro-CT detection showed that the bone repair effect of the three subgroups in the model group was significantly better than that of the corresponding subgroups in the control group,and the bone repair effect of the subgroup in the model group 6 weeks after bone cement implantation was better than that of the subgroups 4 and 8 weeks after bone cement implantation.The results indicate that H-type blood vessels are dynamically expressed in the bone induced membrane and reached a peak 6 weeks after bone cement implantation.Good bone repair effects can be obtained by the bone induced membrane bone grafting 6 weeks after bone cement implantation.