Objective:To investigate personal exposures to nitrogen oxides(NOX)and nitrogen di-oxide(NO2)and the influence of baseline personal characteristics,living environment and daily activity patterns of the participants on the exposures among adults over 35 in Tianjin and Shanghai.Methods:In this panel study,91 healthy nonsmoking adults aged over 35 from Tianjin and Shanghai participated in our study.The study was conducted in summer and winter.The participants were followed for three times with an interval of at least two weeks.Only participants in Shanghai were followed once in winter because of the COVID-19 pandemic.Twenty-seven participants completed follow-up visits in both seasons.We measured their 24 h personal exposures to NOX and NO2and collected their baseline and time-activity in-formation through questionnaire/diary.The linear mixed model was used to analyze the associations be-tween potential influencing factors and personal NOX and NO2 exposure levels.Results:There were 349 follow-up visits with valid 24 h personal NO2 and NOX exposure measurements in the two cities.The ave-rage 24 h personal exposures to NO2 and NOX(volume fraction)in Tianjin participants were 18.0 x 10-9 and 26.2 × 10-9 in summer,and 31.0 x 10-9 and 54.9 x 10-9in winter,respectively;and the average 24 h personal exposures to NO2 and NOX in Shanghai participants were 38.7 x 10-9and 100.0x10-9in summer,and 45.5 x10-9 and 139.2 x 10-9 in winter,respectively.The results of univariate regression analysis showed that their personal NOX exposure levels were significantly associated with city,season,gender,average daily cooking times,and ambient NO2 concentrations measured at fixed-site monitoring stations.In addition to the above factors,the personal NOX exposure levels were also significantly associ-ated with educational level and the personal NO2 exposure levels were also significantly associated with passive smoking,average daily home time,cooking energy type,residential distance from main traffic road,and use of kitchen ventilators.Multivariate regression analysis showed that the personal exposure levels of NO2 and NOX were significantly lower in Tianjin than that in Shanghai,were significantly lower in summer than that in winter,and were significantly and positively associated with ambient NO2 concen-trations measured at fixed-site monitoring stations.In addition,personal NOX exposure levels were signifi-cantly lower in females than in males,and personal NO2 exposure levels were significantly positively asso-ciated with average daily cooking times and significantly inversely associated with average daily home time.For every interquartile range(IQR)increase(12.7 × 10-9)in ambient NO2,the personal NO2 exposure levels increased by 27.5％(95％CI:17.0％-38.9％),and personal NOX exposure levels in-creased by 16.1％(95％CI:7.1％-25.8％).Conclusion:Season,city and ambient NO2 concentra-tions are significant influencing factors of personal exposure levels of NO2and NOX At the same time,the personal exposures levels of NO2 are also affected by lifestyle factors.Our study provides scientific evi-dence for making precise air pollution control decisions and reducing the exposure levels of NOX in the population.

Objective The fully automatic segmentation of glioma and its subregions is fundamental for computer-aided clinical diagnosis of tumors.In the segmentation process of brain magnetic resonance imaging(MRI),convolutional neural networks with small convolutional kernels can only capture local features and are ineffective at integrating global features,which narrows the receptive field and leads to insufficient segmentation accuracy.This study aims to use dilated convolution to address the problem of inadequate global feature extraction in 3D-UNet.Methods 1)Algorithm construction:A 3D-UNet model with three pathways for more global contextual feature extraction,or 3DGE-UNet,was proposed in the paper.By using publicly available datasets from the Brain Tumor Segmentation Challenge(BraTS)of 2019(335 patient cases),a global contextual feature extraction(GE)module was designed.This module was integrated at the first,second,and third skip connections of the 3D UNet network.The module was utilized to fully extract global features at different scales from the images.The global features thus extracted were then overlaid with the upsampled feature maps to expand the model's receptive field and achieve deep fusion of features at different scales,thereby facilitating end-to-end automatic segmentation of brain tumors.2)Algorithm validation:The image data were sourced from the BraTs 2019 dataset,which included the preoperative MRI images of 335 patients across four modalities(T1,T1ce,T2,and FLAIR)and a tumor image with annotations made by physicians.The dataset was divided into the training,the validation,and the testing sets at an 8∶1∶1 ratio.Physician-labelled tumor images were used as the gold standard.Then,the algorithm's segmentation performance on the whole tumor(WT),tumor core(TC),and enhancing tumor(ET)was evaluated in the test set using the Dice coefficient(for overall effectiveness evaluation),sensitivity(detection rate of lesion areas),and 95%Hausdorff distance(segmentation accuracy of tumor boundaries).The performance was tested using both the 3D-UNet model without the GE module and the 3DGE-UNet model with the GE module to internally validate the effectiveness of the GE module setup.Additionally,the performance indicators were evaluated using the 3DGE-UNet model,ResUNet,UNet++,nnUNet,and UNETR,and the convergence of these five algorithm models was compared to externally validate the effectiveness of the 3DGE-UNet model.Results 1)In internal validation,the enhanced 3DGE-UNet model achieved Dice mean values of 91.47%,87.14%,and 83.35%for segmenting the WT,TC,and ET regions in the test set,respectively,producing the optimal values for comprehensive evaluation.These scores were superior to the corresponding scores of the traditional 3D-UNet model,which were 89.79%,85.13%,and 80.90%,indicating a significant improvement in segmentation accuracy across all three regions(P＜0.05).Compared with the 3D-UNet model,the 3DGE-UNet model demonstrated higher sensitivity for ET(86.46%vs.80.77%)(P＜0.05),demonstrating better performance in the detection of all the lesion areas.When dealing with lesion areas,the 3DGE-UNet model tended to correctly identify and capture the positive areas in a more comprehensive way,thereby effectively reducing the likelihood of missed diagnoses.The 3DGE-UNet model also exhibited exceptional performance in segmenting the edges of WT,producing a mean 95%Hausdorff distance superior to that of the 3D-UNet model(8.17 mm vs.13.61 mm,P＜0.05).However,its performance for TC(8.73 mm vs.7.47 mm)and ET(6.21 mm vs.5.45 mm)was similar to that of the 3D-UNet model.2)In the external validation,the other four algorithms outperformed the 3DGE-UNet model only in the mean Dice for TC(87.25%),the mean sensitivity for WT(94.59%),the mean sensitivity for TC(86.98%),and the mean 95%Hausdorff distance for ET(5.37 mm).Nonetheless,these differences were not statistically significant(P＞0.05).The 3DGE-UNet model demonstrated rapid convergence during the training phase,outpacing the other external models.Conclusion The 3DGE-UNet model can effectively extract and fuse feature information on different scales,improving the accuracy of brain tumor segmentation.

BackgroundDue to the COVID-19 pandemic， both teenagers' studies and personal life are critically affected， which has resulted in a variety of mental health problems. In this regard， scholars at home and abroad have carried out a large number of research concerning adolescent mental health， of which there still exists a lack of systematic combing and review. ObjectiveTo understand the status and development trend of research on adolescent mental health during the COVID-19 pandemic at home and abroad， and to grasp the current research hotspots and trends in this field， so as to provide references for relevant research and practice in the post-epidemic era. MethodsOn October 30， 2022， we searched through China Knowledge Network Infrastructure （CNKI） and Web of Science database， and the publishing time of articles to be retrieved was limited between December 1， 2019 and October 30， 2022. Excel and CiteSpace were used to perform visual analysis on these articles in terms of number， author， institution， country and keywords of the articles. ResultsA total of 7 608 articles were included. At home and abroad， the number of papers related to adolescent mental health generally increased at first and then decreased under the pandemic situation. Compared with foreign countries， the connection and cooperation among domestic scholars and institutions was not close enough. The top three countries in the number of English literature published were the United States， Britain and China， and those in intermediary center were Tunis， Cameroon and Anguilla. The parent-child relationship and mental health of teenagers during were much concerned by scholars both at home and abroad. With the passage of time， researchers at home and abroad had shifted their focus from only negative factors to positive factors. ConclusionChinese scholars or institutions need to strengthen more domestic and international exchanges and cooperation. Scholars from different countries can carry out cross-cultural study on research topics of common concern， and continue to explore the positive psychological changes of teenagers in the post-epidemic era.［Funded by National Social Science Foundation 2020 Education Youth Project of 13th Five-Year Plan （number， CHA200259）］

OBJECTIVE To establish a method for simultaneous determination of two third-generation anti-epileptic medicines such as lacosamide and perampanel in human plasma and apply this method in clinical practice. METHODS Using clozapine as internal standard， the concentrations of lacosamide and perampanel of plasma samples in 10 epileptic patients were determined by LC-MS/MS after protein precipitation with acetonitrile and dilution with acetonitrile-water （20∶80，V/V）， and the plasma minimum concentrations were obtained by dilution of multiple. The determination was performed on Welch Ultimate XB-C18 column， with mobile phase A consisted of 10 mmol/L ammonium formate and mobile phase B consisted of methanol-acetonitrile-isopropanol （0.2% formic acid） mixed solution （7∶1.5∶1.5， V/V/V） for gradient elution at the flow rate of 0.4 mL/min. The column temperature was set at 40 ℃ ， and the sample size was 5 μL. The electrospray ion source and multi-reaction monitoring mode were used for positive iron scanning. The ion pair used for quantitative analysis of lacosamide， perampanel and internal standard were m/z 251.2→ 144.1， m/z 350.2→219.2 and m/z 327.2→270.0， respectively. RESULTS The linear ranges of lacosamide and perampanel were 0.001 25-0.125 μg/mL（r＞0.99）， 0.037 5-3.75 ng/mL （r＞0.99）； the limits of quantification were 0.001 25 μg/mL and 0.037 5 ng/mL， respectively. The precision and accuracy within and between batches， extraction recovery rate， matrix effect， and stability all met relevant requirements. The minimum concentrations of lacosamide in No. 1-5 patients were 5.3-12.2 μg/mL， and the minimum concentrations of perampanel in No.6-10 patients were 208-510 ng/mL， respectively. CONCLUSIONS The established method is simple， rapid and suitable for the therapeutic drug monitoring of lacosamide and perampanel.

Objective To study the potential efficacy of transplanted bone marrow-derived mesenchymal stem cells (MSCs) in treating and repairing the acute lung injury in animal models. Methods MSCs were isolated from mouse bone marrow, cultrued and amplified in vitro. The lipopolysaccharide (LPS) was inhaled through postnasal tract to cause acute lung injury in mice and the MSCs labeled by Brdu were administrated via vein into the mice. The migration and differention of the cells were identified by immunostaining and double immunostaining. The pathological changes, pulmonary edema index and the content of IL-1β in lung homogenate were used to accese the therapeutical effect of MSCs. Results The cultured MSCs dispalyed a positive CD44 and a negative CD34. The Brdu-labeled cells were detected in the lungs of the recipient 4 days after transplantation, indicating its origin of MSCs. Theses cells also exhibited characteristics of aveolar epithelials, expressing the cytokeratin-the marker of epithelium. Compared with the injuried ones, the mice treated with MSCs showed a decreased pulmonary edema in-dex and IL-1β content in the lung homogenate. Conclusion These data suggest a therapeutical effects of MSCs in treating and repairing the mouse acute lung injury.