Aerosol removal using flame-retardant atomized fixatives, as a major means of aerosol control, has achieved remarkable results in the field of nuclear facility decommissioning and decontamination. Traditional atomized fixatives for aerosol removal have deficiencies in high-temperature resistance and flame retardancy, rendering them inadequate for operational scenarios involving high temperatures and flammability encountered during nuclear decommissioning. This paper investigates the current development of flame-retardant atomized fixatives for aerosol removal both domestically and internationally and presents a preliminary exploration of this technology. The experiments showed that atomized fixatives modified with flame-retardant properties not only maintained excellent aerosol capture efficiency, but also exhibited significantly improved flame-retardant performance. This confirmed the technical feasibility of the proposed approach. Finally, suggestions and reflections are proposed for the development of this technology and its application in nuclear facility decommissioning.

Objective: To investigate the prevalence and associated factors of depressive symptoms among junior and senior high school students in Beijing from 2019 to 2023, in order to provide a scientific basis for interventions targeting high risk groups. Methods: From 2019 to 2023, a stratified cluster random sampling method was used to select 88 927 junior and senior high school students from 16 districts in Beijing. The Center for Epidemiologic Studies Depression Scale(CES-D) was conducted to assess depressive symptoms. The Chi square test was used to compare the detection rates of depressive symptoms among different student groups, and the trend Chi square test was employed for trend analysis of detection rates across the years. Multivariate Logistic regression analysis was applied to examine the association between the detection of depressive symptoms and related factors among junior and senior high school students. Results: From 2019 to 2023, the prevalence rates of depressive symptoms among junior and senior high school students in Beijing were 20.45%, 18.19%, 16.64%, 17.89% and 18.17%, respectively, with an overall downward trend ( χ 2 trend =27.51, P <0.01). Multivariate Logistic regression analysis revealed that after adjusting for gender, monitoring year, educational stage,family structure,boarding status and has taken a medical leave of absence in the past year unhealthy dietary behaviors ( OR=1.80, 95%CI =1.73-1.87), physical inactivity ( OR=1.24, 95%CI =1.19-1.29), try smoking ( OR=1.46, 95%CI =1.35-1.58), try alcohol( OR=1.96, 95%CI =1.88-2.05), Internet addiction ( OR=3.88, 95%CI =3.57-4.22), and adverse ear related behavior ( OR=1.82, 95%CI =1.71-1.93) were all associated with an increased risk of depressive symptoms among junior and senior high school students (all P <0.05). Conclusions The prevalence depression symptoms among middle school students in Beijing showed a fluctuating downward trend from 2019 to 2023. Targeted interventions should be adopted to reduce the occurrence of depression symptoms among junior and senior high school students.

Objective: To understand the trends of classroom lighting and illumination of primary and secondary schools in Beijing from 2016 to 2023, so as to provide a scientific basis for targeted improvement measures. Methods: A sampling survey was conducted on the lighting and illumination indicators of 8 390 classrooms in primary and secondary schools in Beijing from 2016 to 2023. The survey included classroom daylight factor, window to floor area ratio, average illuminance and illuminance uniformity on the desks, average illuminance and illuminance uniformity on blackboards, as well as classroom lighting and blackboard illumination sources. Intergroup comparisons were performed using the Kruskal-Wallis H test and the Chi square test, and Spearman correlation analysis was used to examine the trend of classroom lighting and illumination changes. Results: Except the window to floor area ratio, the measured values and compliance rates of all lighting and illumination indicators showed an overall upward trend from 2016 to 2023 (daylight factor r = 0.27, χ 2 trend =206.80, average illuminance on the desk surface r =0.30, χ 2 trend =87.97, illuminance uniformity on the desk surface r =0.14, χ 2 trend =73.59, average illuminance on the blackboard r =0.33, χ 2 trend =477.43, illuminance uniformity on the blackboard r = 0.09, χ 2 trend =50.76) (all P ＜0.01). The lighting and illumination indicators of classrooms (included classroom daylight factor, average illuminance and illuminance uniformity on the desks, average illuminance and illuminance uniformity on blackboards) in urban schools, primary schools, and secondary schools from 2016 to 2023 showed an upward trend (urban r =0.23-0.40, χ 2 trend =88.66-392.18; primary school r =0.12-0.36, χ 2 trend =39.50-281.44; secondary schools r =0.06-0.31, χ 2 trend =11.79-213.73) (all P ＜ 0.01 ). The illuminance uniformity on the blackboard in suburban schools showed a downward trend ( r = -0.09, χ 2 trend =31.53, both P ＜0.01). The illuminance uniformity on the desk surface in suburban schools showed no significant change ( r =0.03, χ 2 trend =1.23, both P ＞0.05). The other indicators showed an upward trend (daylight factor r =0.28, χ 2 trend =40.69, average illuminance on the desk surface r =0.24, χ 2 trend =16.35, average illuminance on the blackboard r =0.25, χ 2 trend =118.05, all P ＜0.01). The trends of classroom and blackboard illumination sources were that fluorescent lamps decreased year by year and LED lamps increased by year (classroom illumination sources χ 2 trend =1 059.82, blackboard illumination sources χ 2 trend =1 070.25, both P ＜0.01). Conclusions The classroom lighting and illumination in primary and secondary schools in Beijing has shown an overall improving trend from 2016 to 2023. However, problems remain, such as limited improvement of illuminance uniformity indicators, late start and poor effect of reconstruction in suburban schools. Further improvements are still needed.

Objective To explore the predictive value of peripheral blood cells in the efficacy of neoadjuvant immunotherapy combined with chemotherapy for esophageal squamous cell carcinoma. Methods A retrospective study was conducted on patients with esophageal squamous cell carcinoma (clinical stages Ⅱ-Ⅳa) who underwent neoadjuvant immunotherapy combined with chemotherapy at the Department of Thoracic Surgery, Affiliated Hospital of North Sichuan Medical College from April 2020 to November 2023. According to whether the pathology was completely relieved after treatment, patients were divided into a pathological complete remission group and a pathological incomplete remission group. The College of American Pathologists criteria were used to evaluate the tumor pathological regression grade (TRG) after neoadjuvant therapy (TRG=0, 1 defined as a good efficacy group, TRG=2, 3 defined as a poor efficacy group). Results A total of 92 patients with esophageal squamous cell carcinoma were collected, including 72 males and 20 females. The average age was (65.86±7.66) years. The complete remission of pathology was closely related to the number of lymphocytes in the blood before treatment (P=0.019). The area under the curve (AUC) for predicting complete remission of esophageal squamous cell carcinoma after neoadjuvant immunotherapy combined with chemotherapy was 0.678, the maximum Youden index was 0.328, and the optimal cutoff value was 1.845. The incidence of postoperative pulmonary infection in the pathological incomplete remission group was higher than that in the pathological complete remission group (25.0% vs. 5.6%, P=0.030). Using the optimal cutoff value, there were statistically significant differences in pathological N stage and pathological TNM stage between patients with lymphocyte counts <1.845×109/L and ≥1.845×109/L (P<0.05). Treatment response (by TRG) was significantly associated with the pretreatment red blood cell count (P=0.009). The AUC for predicting a good TRG response was 0.669, with a maximum Youden index of 0.385 and an optimal cutoff value of 4.235. Between the good and poor response groups, there were statistically significant differences in postoperative pathological T stage (P<0.001), N stage (P=0.041), and TNM stage (P＜0.001). When stratified by the optimal cutoff value, there were statistically significant differences in age (P＜0.001) and the prevalence of hypertension (P=0.022) between patients with red blood cell counts <4.235×1012/L and ≥4.235×1012/L. Conclusion A pretreatment absolute lymphocyte count ≥1.845×109/L and a red blood cell count <4.235×1012/L are good predictors for pathological complete response and a good pathological response, respectively, following neoadjuvant immunotherapy combined with chemotherapy in patients with esophageal squamous cell carcinoma.

Objective To investigatethe relationship between gastroesophageal reflux disease (GERD) symptoms and clinicopathological characteristics, p53 expression, and survival of Chinese patients with esophageal adenocarcinoma. Methods A total of 3882 patients with esophageal adenocarcinoma, 970 matched patients with esophageal squamous cell carcinoma, and 970 matched patients with gastric cardia adenocarcinoma were included to compare the incidence of GERD symptoms. Patients with esophageal adenocarcinoma were divided into two groups according to the presence and absence of GERD symptoms. The differences in clinicopathological characteristics and p53 expression between the two groups were compared by chi-square test, and the differences in survival between the two groups were compared by landmark analysis. Results The incidence of GERD symptoms increased successively in esophageal squamous cell carcinoma, esophageal adenocarcinoma, and gastric cardia adenocarcinoma. In patients with esophageal adenocarcinoma, the proportions of male, less than 65 years old, lower thoracic tumors, tumors without squamous cell carcinoma, poorly differentiation, early tumors (stage 0-I), and p53-positive tumors in the group with GERD symptoms were higher than those in the group without GERD symptoms; moreover, the long-term survival (≥15 years) was better. Conclusion GERD symptom is an important clinical sign of esophageal adenocarcinoma. It is closely related to specific clinicopathological characteristics, p53 overexpression, and good long-term prognosis.

Objective To propose a whole-life cycle management model for valvular heart disease (VHD), systematically elucidate its underlying logic and implementation pathways, and concurrently review and analyze its preliminary application outcomes. Methods Since 2020, West China Hospital of Sichuan University has established a management system encompassing "assessment-decision-intervention-follow-up", including: (1) a risk-stratified, tiered management pathway; (2) six core functions ("promotion, screening, prevention, diagnosis, treatment, and rehabilitation") coordinated by disease-specific managers; (3) an intelligent decision support information platform; and (4) a collaborative network of multidisciplinary teams and regional academic alliances. To evaluate the effectiveness of this management model, we retrospectively included three cohorts: (1) the population screened by echocardiography from 2020 to 2024, analyzing the detection rate of aortic valve disease and risk stratification; (2) patients enrolled in the whole-life cycle management from April 2021 to December 2024, assessing follow-up outcomes, hospital satisfaction, and changes in quality of life; (3) patients who underwent transcatheter aortic valve replacement (TAVR) from January 2022 to January 2024, evaluating the one-year all-cause mortality rate, perioperative complications, and improvements in New York Heart Association (NYHA) classification. Results Between 2020 and 2024, a total of 583 874 individuals underwent echocardiographic screening. A total of 48 089 patients with aortic valve disease were identified, including 3 401 (7.1%) high-risk patients, 18 657 (38.8%) moderate-risk patients, and 26 031 (54.1%) low-risk patients. Among them, 2 417 patients were enrolled in whole-life cycle management. Patient satisfaction scores showed a yearly increase, rising from 73.89 points before 2020 to 93.74 points in 2024. The 1-year mortality rate in the TAVR cohort decreased to 5.3%, significantly lower than the 8.2% observed under early standard management between 2014 and 2019 (P<0.01). Conclusion Through process optimization and resource integration, the VHD whole-life cycle management model has demonstrated significant effectiveness in standardizing diagnostic and follow-up procedures, enhancing patient satisfaction and quality of life, and reducing mortality. These outcomes highlight its practical value for broader implementation in China.

Objective To compare the effects of different detector combinations of 320-row CT on the image quality and radiation dose of head CT to explore the feasibility of using a wide detector for head CT scanning.Methods Totally 100 patients underwent head CT scanning due to trauma or cerebrovascular disease at some hospital from June to August 2023 were collected prospectively and divided into group A and group B by using block randomization grouping method,with the length of the block group being 2 and 50 patients in each group.In group A,all the detectors had the widths at z-axis direction being 40×0.5 mm and head scanning was completed after multiple exposures;in group B,detector combinations with widths of 280×0.5 mm or 320×0.5 mm were chosen based on the patient's head size in the head-foot direction(z-axis direction),and head scanning was performed with a single-turn exposure.The remaining scanning and image reconstruction parameters in the two groups were kept completely consistent.The head image quality of the 2 groups was evaluated objectively and scored subjectively by 2 radiologists.The volume CT dose index(CTDIvol),dose length product(DLP)and exposure time of the 2 groups were recorded,and the effective dose(ED)was calculated.SPSS 22.0 software was used for statistical analysis.Results In terms of objective evaluation of image quality,at the level of the parietal skull group B had the CT value of gray matter,image noise and contrast to noise ratio(CNR)of the images higher than those of group A,and the differences were statistically significant(all P<0.05);at the level of the posterior skull group B had the CT values of gray and white matter,image noise and air noise lower while CNR higher than those of group A,and the differences were statistically significant(all P<0.05).In terms of subjective scoring of image quality,at the levels of parietal and posterior skull group A behaved better than group B,and the differences were statistically significant(all P<0.05).In group A 5 patients had obvious motion artifacts affecting the diagnosis and the image quality scores not higher than 2,and secondary scanning had to be carried out;In group B all the patients had no obvious motion artifacts and met the diagnosis requirements.When compared with group A Group B had the CTDIvol,DLP,ED and exposure time decreased by 17.44%,17.24%,17.48%and 85.53%,respectively,and the differences were statistically significant(all P<0.05).Conclusion A wide detector gains advantages over a 20 mm detector in image quality when 320-row CT is used for head CT scanning,with the diagnosis requirements satisfied.[Chinese Medical Equipment Journal,2025,46(4):57-62]

Objective To analyze the correlation between right atrial strain at various stages and various influencing factors in patients with pulmonary hypertension,and to explore the role of right atrial strain in the assessment of pulmonary hypertension.Methods A total of 239 cases diagnosed with pulmonary hypertension who underwent echocardiography and complete right heart catheterization at hospital from October 2021 to December 2023 were included.Conventional ultrasound parameters such as right heart strain,right atrial area(RA area),inferior vena cava diameter(IVC diameter),and collapse rate of the inferior vena cava(IVC diameter changes)were measured.The heart rate(HR)corresponding to the ultrasound images were recorded.General information such as age and gender,as well as catheter data including mean right atrial pressure(mRAP),mean pulmonary artery pressure(mPAP),and pulmonary vascular resistance(PVR),were collected.The relationship between right atrial strain and its influencing factors was analyzed,and further analysis was conducted by dividing into shunt group and non-shunt group based on the presence or absence of left-to-right shunt disease.Results The correlation with RA reservoir strain(RASr)from high to low is RV global strain(RV4CSL),RV free wall strain(RVFWSL),RA area,IVC diameter,mRAP,age,HR,and PVR;the correlation with RAconduit strain(RAScd)from high to low is RV4CSL,RVFWSL,RA area,IVC diameter,mRAP,age,PVR,and HR;the correlation with RA contraction strain(RASct)from high to low is RA area,RV4CSL,RVFWSL,mRAP,IVC diameter,and HR.The collapse rate of the inferior vena cava is correlated with strain at various stages of the right atrium;gender is correlated with RASr and RASct.Conclusions Right atrial strain can reflect changes in right atrial function,with the highest correlation to right ventricular strain and right atrial area.Right atrial strain can indicate the severity of right ventricular function and right atrial remodeling,serving as an evaluative index for the condition and treatment outcomes of pulmonary arterial hypertension.

Thoracic anesthesia with spontaneous respiration represents a form of precision anesthesia meticulously customized to individual patients.Considering the more stringent requirements this anesthesia approach imposes on the regulation of respiratory function,the writing group of the"Consensus of Experts on the Management of Thoracic Anesthesia with Spontaneous Respiration"has formulated elaborate guidelines regarding indications and contraindications,preoperative evaluation,anesthesia implementation,common complications,and treatment strategies.This was accomplished by referencing relevant domestic and international literature and integrating it with actual clinical requirements.The objective is to standardize the rational application of this anesthesia method.

Objective The isokinetic muscle strength indicators and surface electromyography(sEMG)signals of the healthy lower limb side of patients with non-contact anterior cruciate ligament(ACL)injury in the acute phase were compared with those of healthy individuals,so to provide a theoretical basis for the prevention of secondary ACL rupture in the healthy lower limb side of patients with ACL injury.Methods 21 patients with ACL injury in the acute phase(ACL injury group)and 21 healthy individuals(control group)were subjected to isokinetic muscle strength tests for hip flexion,extension,adduction,abduction,and knee flexion,and sEMG signals of the vastus medialis,vastus lateralis,semitendinosus,biceps femoris,and gluteus maximus were collected during the single-leg jumping movements.The differences between the two groups in relative peak torque,antagonist muscle ratio,root mean square amplitude,and co-contraction index were analyzed by independent sample t-test.Results The extension of the knee(P=0.040)and hip flexion strength(P=0.041)were lower in the healthy lower limb side of patients with ACL injury.In the single-leg landing action,there were lower activation of the vastus medialis muscle in the pre-activation phase(P=0.014),lower activation of the vastus medialis(P=0.030)and gluteus maximus(P=0.002)in the reaction phase,and also lower co-activation levels of the biceps femoris-semitendinosus(P=0.020).Conclusions At the early stage of injury,the function of the healthy lower limb side of patients with ACL injury changes,which may indicate why these patients face a greater risk of contralateral lower limb injury.