Nitrogen oxides(NOx=NO+NO2)are important precursors of ozone(O3),and NOx and its oxides together constitute reactive nitrogen oxides(NOy)in the atmosphere.A comprehensive understanding of the total NOy level in the atmosphere is of great significance for a deeper understanding of the atmospheric nitrogen cycle and oxidation,as well as for formulating strategies for air pollution prevention and control.In this work,a thermal decomposition-broadband cavity enhanced absorption spectroscopy(TD-BBCEAS)technique for online measurement of total NOy in the atmosphere was developed.With this method,the NOy was efficiently converted into NO2,and the total NOy concentration in the atmosphere was indirectly obtained by measuring NO2.Focusing on the key factors affecting the measurement of total NOy,the influence of NO titration efficiency and other NOy component TD efficiency on measurement accuracy was emphasized.By changing the oxygen(O2)flow rate through the mercury lamp to alter the O3 concentration for titrating NO,the conversion efficiency of NO was evaluated.At O2 flow rate of 6 mL/min,the conversion efficiency of NO was greater than 99%.TD efficiency testing and analysis on NO2,peroxyacetyl nitrate(PAN),nitric acid(HNO3),and nitrous acid(HONO),which account for a large proportion of atmospheric NOy components,was carried out using 680℃as the optimal TD temperature for efficient conversion of NOy.With NO and HONO sample gases as typical verification gases,the conversion efficiency of NOy and the accuracy of NOy measurement by TD-BBCEAS system were verified by switching the on and off modes of mercury lamp and TD device.At integration time of 60 s,the detection limit of the system for NOy was 2.83×1010 molecules/cm3(60 s,2σ).A comparative measurement of actual atmospheric NOy was conducted between the TD-BBCEAS system and the NOy analyzer.The observation results showed a correlation coefficient(R2)of 0.98 and a slope of 0.93,further verifying the feasibility and accuracy of applying the TD-BBCEAS system to measurement of total NOy.

Sarin(GB)is a typical representative of nerve agents with high toxicity,and very low amount can cause death.GB can cause water and atmospheric environment poisoning,so the detection of GB in water and air is of great significance.In this work,a colorimetric sensor array(CSA)based on GB inhibition of cholinesterase activity was constructed to detect GB with high selectivity.A 4×4 colorimetric array was constructed using acetylcholinesterase(AChE),butyryl cholinesterase(BuChE)and the corresponding substrate acetylthiocholine iodide(S-ACh),butyryl thiocholine iodide(S-BCh),acetylcholine chloride(ACh),butyryl choline chloride(BCh)and 2,6-dichloroindophenol ethyl ester(DCIE).The linear curve of the sensor was Y=131.3×lgC+271.6(R2=0.997),where Y was the array response Euclidean distance,C was the concentration of GB(mg/L),the linear range was 0.03?0.32 mg/L,and the detection limit was 27.6 μg/L.The method could effectively distinguish chemical warfare agents(CWA)such as VX,Soman(GD),mustard gas(HD),Louie reagent(L),and had high anti-interference ability,sensitivity and good repeatability.It was successfully applied to the detection of GB in simulated water and simulated air samples,and the sample recovery rate was 97.2% ?100.9%.This method would be potentially applied to the field rapid detection of nerve agents.

Objective: Machine learning (ML) has been reported to have better predictive capability than traditional statistical techniques. The aim of this study was to assess the efficacy of ML algorithms and logistic regression (LR) for predicting depressive symptoms during the COVID-19 pandemic. Methods: Analyses were carried out in a national cross-sectional study involving 21,916 participants. The ML algorithms in this study included random forest (RF), support vector machine (SVM), neural network (NN), and gradient boosting machine (GBM) methods. The performance indices were sensitivity, specificity, accuracy, precision, F1-score, and area under the receiver operating characteristic curve (AUC). Results: LR and NN had the best performance in terms of AUCs. The risk of overfitting was found to be negligible for most ML models except for RF, and GBM obtained the highest sensitivity, specificity, accuracy, precision, and F1-score. Therefore, LR, NN, and GBM models ranked among the best models. Conclusion Compared with ML models, LR model performed comparably to ML models in predicting depressive symptoms and identifying potential risk factors while also exhibiting a lower risk of overfitting.

OBJECTIVE: To investigate the relationship between physical activity and genetic risk and their combined effects on the risk of developing chronic obstructive pulmonary disease. METHODS: This prospective cohort study included 318,085 biobank participants from the UK. Physical activity was assessed using the short form of the International Physical Activity Questionnaire. The participants were stratified into low-, intermediate-, and high-genetic-risk groups based on their polygenic risk scores. Multivariate Cox regression models and multiplicative interaction analyses were used. RESULTS: During a median follow-up period of 13 years, 9,209 participants were diagnosed with chronic obstructive pulmonary disease. For low genetic risk, compared to low physical activity, the hazard ratios ( HRs) for moderate and high physical activity were 0.853 (95% confidence interval [ CI]: 0.748-0.972) and 0.831 (95% CI: 0.727-0.950), respectively. For intermediate genetic risk, the HRs were 0.829 (95% CI: 0.758-0.905) and 0.835 (95% CI: 0.764-0.914), respectively. For participants with high genetic risk, the HRs were 0.809 (95% CI: 0.746-0.877) and 0.818 (95% CI: 0.754-0.888), respectively. A significant interaction was observed between genetic risk and physical activity. CONCLUSION Moderate or high levels of physical activity were associated with a lower risk of developing chronic obstructive pulmonary disease across all genetic risk groups, highlighting the need to tailor activity interventions for genetically susceptible individuals.
Humans ; Pulmonary Disease, Chronic Obstructive/epidemiology* ; Exercise ; Male ; Female ; Middle Aged ; Prospective Studies ; Aged ; Genetic Predisposition to Disease ; Risk Factors ; United Kingdom/epidemiology* ; Incidence ; Adult

Objective:To investigate the relationship between 18F-fluoro-2-deoxy-d-glucose positron emission tomography/computed tomography(18F-FDG PET/CT)and tumor markers and the prognosis of patients with differentiated thyroid cancer(DTC)treated with surgery combined with iodine-131,and to construct a nomogram prediction model.Methods:The clinical data of 134 patients with DTC who underwent surgery combined with iodine-131 treatment in our hospital from January 2021 to January 2023 were retrospectively analyzed.According to the prognosis after 1 year of treatment,they were divided into a good prognosis group(n=106)and a poor prognosis group(n=28).The general data,18F-FDG PET/CT related parameters[maximum standardized uptake value(SUVmax),metabolic volume(MTV),total lesion gly-colysis(TLG)]and serum tumor markers[thyroglobulin(Tg),thyroglobulin antibody(TgAb)]levels were compared between the two groups.Pearson correlation coefficient was used to analyze the correlation between the related parameters and the tumor marker levels.Logistic multivariate analysis was used to analyze the influencing factors of DTC prognosis.Re-ceiver operating characteristic curve(ROC)was used to analyze the predictive efficacy of related parameters combined with tumor markers on poor prognosis.Anomogram prediction model for poor prognosis was constructed and the predic-tive efficacy of the model was evaluated.Results:The proportion of stage Ⅲ-Ⅳ,the proportion of total resection and the levels of thyroid stimulating hormone(TSH),SUVmax,MTV,TLG,Tg and TgAb in the poor prognosis group were higher than those in the good prognosis group,and the differences were statistically significant(P<0.05).Pearson correlation co-efficient showed that SUVmax,MTV,TLG and Tg,TgAb levels were positively correlated with tumor markers(P<0.05).Lo-gistic analysis showed that after adjusting for confounding variables,SUVmax,MTV,TLG,Tg and TgAb were independent influencing factors for the poor prognosis of DTC(P<0.05).ROC analysis showed that the combination of SUVmax,MTV,TLG,Tg and TgAb was significantly better than each parameter alone in predicting poor prognosis(P<0.05).The nomo-gram prediction model was constructed.ROC evaluation showed that the model had good prediction performance.K-fold cross validation showed that the model had stable performance and good generalization ability.Conclusion:The 18F-FDG PET/CT related parameters SUVmax,MTV,TLG and tumor markers Tg and TgAb are all independent factors affecting the poor prognosis of DTC patients treated with surgery combined with iodine-131.The prognostic nomogram prediction model based on the above factors has good predictive efficacy and can be used to guide clinical decision-making.

Objective:To investigate the factors influencing the delayed onset of intrapartum fever following epidural labor analgesia and their impact on maternal and neonatal outcomes.Methods:Select parturients who experienced intrapartum fever following labor analgesia(T≥38.0℃,age≥18 years,singleton pregnancy,ASA classification Ⅱ)between January 1,2021,and December 31,2023.Group them based on the median time of intra-partum fever onset after labor analgesia:those with onset times less than the median were classified as the ear-ly-onset fever group,and those with onset times greater than the median were classified as the late-onset fever group.Using univariate and multivariate Logistic regression analysis to explore factors influencing the delay in in-trapartum fever onset and the pregnancy outcomes of the mothers and newborns in both groups.Results:A total of 253 parturients were included,and the time range of onset of intrapartum fever following epidural labor analgesi-a was 1.83-28.42 hours,with a median fever onset time of 8.00 hours.There were 126 cases in the early-onset group and 127 in the late-onset group.Multivariate Logistic regression analysis indicated that primiparous women,artificial membrane rupture,and neonatal birth weight were independent risk factors for delayed fever onset(OR＞1,P＜0.05),whereas the administration of oxytocin prior to labor analgesia was found to be a protective factor(OR＜1,P＜0.05).The late-onset group exhibited higher levels of white blood cells(WBC),C-reactive pro-tein,longer hospital stays,higher hospitalization costs,greater diagnosis rates of chorioamnionitis,higher NICU ad-mission rates,as well as a higher incidence of neonatal pneumonia,for newborns compared to the early-onset group(P＜0.05).Conclusions:Primiparous women,artificial membrane rupture,and higher neonatal birth weight may be associated with delayed onset of intrapartum fever,while oxytocin administration prior to labor analgesia may offer some protective benefit.The later the onset of intrapartum fever,the worse the clinical outcomes for both mother and infants.

Recent studies have shown that the physiological homeostasis of oral mucosal cells is regulated by the circadian clock.Dis-ruption or dysfunction of the circadian clock is closely associated with the development of oral squamous cell carcinoma(OSCC).Research based on the circadian clock offers a novel perspective on the pathogenesis and therapeutic strategies for OSCC.However,there is current-ly limited research on this topic,and people generally have insufficient understanding and recognition of the circadian clock.Given the complexity and challenges of circadian clock which is the fourth dimension of medical research,we organize relevant experts based on summarizing the current research results of circadian clock in the pathogenesis and precision diagnosis and treatment of OSCC,combining the scientific principles of the circadian clock's role and their long-term research experience,then summarizes and recommends the con-sensus opinions for the research of circadian clock in the pathogenesis mechanism and precision diagnosis and treatment of human OSCC,with the hope of providing guidance for the basic research and clinical application of circadian clock or circadian rhythm in the pathogene-sis mechanism and precision diagnosis and treatment of oral and maxillofacial squamous cell carcinoma.

The principe of electrical impedance tomography(EIT)was described,and the research progress of EIT technology in the field of gesture recognition was reviewed from the aspects of hardware system and gesture recognition algorithm.The challenges of EIT technology applied in the field of gesture recognition were analyzed,and the future development trends were envisioned.[Chinese Medical Equipment Journal,2025,46(4):93-99]

Objective:To investigate the efficacy and safety of lenvatinib plus drug-eluting bead transarterial chemoembolization (DEB-TACE) and FOLFOX-based hepatic arterial infusion chemotherapy (Len+DEB-TACE+HAIC) versus lenvatinib plus DEB-TACE (Len+DEB-TACE) for hepatocellular carcinoma (HCC) larger than 7 cm with portal vein tumor thrombosis (PVTT).Methods:The data from patients diagnosed with HCC (>7 cm) and PVTT who received either Len+DEB-TACE+HAIC ( n=99) or Len+DEB-TACE ( n=102) between July 2019 and June 2021 at six institutions in China were collected and retrospectively analyzed. Tumor responses were evaluated based on modified Response Evaluation Criteria in Solid Tumors. Objective response rate (ORR), disease control rate (DCR), time to progression (TTP), overall survival (OS), and treatment-related adverse event (TRAE) were compared between the two groups by propensity score matching. Subgroup analyses were performed for TTP and OS. Results:After propensity score matching, 83 pairs of patients were included in the study cohorts. The ORR for the Len+DEB-TACE+HAIC group and the Len+DEB-TACE group was 66.3% and 38.6% ( χ2=12.78, P<0.001), respectively. The DCR for the Len+DEB-TACE+HAIC group and the Len+DEB-TACE group was 91.6% and 79.5% ( χ2=4.87, P=0.027), respectively. The median TTP and median OS for the Len+DEB-TACE+HAIC group were significantly longer than those for the Len+DEB-TACE group (TTP, 10.1 months vs. 6.1 months, χ2=35.28, P<0.001; OS, 17.3 months vs. 12.9 months, χ2=16.84, P<0.001). The incidence of ≥grade 3 TRAEs was 38.6% in the Len+DEB-TACE+HAIC group and 33.7% in the Len+DEB-TACE group ( χ2=0.42, P=0.518). Conclusion:Compared with Len+DEB-TACE, Len+DEB-TACE+HAIC led to improved tumor response, TTP and OS with an acceptable safety profile in patients with large HCC and PVTT.