1.Validation and Forensic Application of a Domestic Human DNA Quantitative De-tection Kit
Jing CHEN ; Ya-Ping WANG ; Yun-Peng FENG ; Xiao-Xin HU ; Zhen-Jun JIA ; Hong-Di LIU ; An-Xin YAN ; Yong-Jiu LI ; Zhu PENG ; Zhi-Fang LIU ; Jian-Gang CHEN
Journal of Forensic Medicine 2025;41(3):252-259
Objective To verify the efficacy of a domestic human DNA quantification kit based on real-time fluorescence quantitative PCR in detecting the total human DNA concentration,male DNA concen-tration in mixed male/female DNA samples,the degree of DNA degradation and inhibitor tolerance.Methods Samples with different concentrations,different male/female ratios,different concentrations of inhibitors,and different degradation degrees were tested using the domestic human DNA quantification kit based on real-time fluorescence quantitative PCR.This kit was compared with a similar product on the market and was applied to the detection of DNA from real cases.Results This human DNA quan-tification kit can effectively detect human DNA as low as 0.001 65 ng/μL,and 6.25 pg/μL of male DNA in mixed samples with a male-to-female ratio of 1∶15 000.Even when the sample contains as high as 400 ng/μL of humic acid or 1 000 μmol/L of hemin alone,the DNA concentration can still be accurately detected.The degradation index can effectively characterize the degradation degree of the sample.This kit has been successfully applied in forensic practice.Conclusion This human DNA quan-tification kit is accurate and reliable in detection.It can accurately reflect the degradation of DNA and inhibitor tolerance.It has good performance in quantitative accuracy,determination of the male/female ratio in mixed samples,and inhibitor tolerance.It has application potential in forensic case examination.
2.Effects of total extract of Anthriscus sylvestris on immune inflammation and thrombosis in rats with pulmonary arterial hypertension based on TGF-β1/Smad3 signaling pathway.
Ya-Juan ZHENG ; Pei-Pei YUAN ; Zhen-Kai ZHANG ; Yan-Ling LIU ; Sai-Fei LI ; Yuan RUAN ; Yi CHEN ; Yang FU ; Wei-Sheng FENG ; Xiao-Ke ZHENG
China Journal of Chinese Materia Medica 2025;50(9):2472-2483
This study aimed to explore the effects and mechanisms of total extracts from Anthriscus sylvestris on pulmonary hypertension in rats. Sixty male SD rats were divided into normal(NC) group, model(M) group, positive drug sildenafil(Y) group, low-dose A. sylvestris(ES-L) group, medium-dose A. sylvestris(ES-M) group, and high-dose A. sylvestris(ES-H) group. On day 1, rats were intraperitoneally injected with monocrotaline(60 mg·kg~(-1)) to induce pulmonary hypertension, and the rat model was established on day 28. From days 15 to 28, intragastric administration of the respective treatments was performed. After modeling and treatment, small animal echocardiography was used to detect the right heart function of the rats. Arterial blood gas was measured using a blood gas analyzer. Hematoxylin and eosin(HE) staining and Masson staining were performed to observe cardiopulmonary pathological damage. Flow cytometry was used to detect apoptosis in the lung and myocardial tissues and reactive oxygen species(ROS) levels. Western blot was applied to detect the expression levels of transforming growth factor-β1(TGF-β1), phosphorylated mothers against decapentaplegic homolog 3(p-Smad3), Smad3, tissue plasminogen activator(t-PA), and plasminogen activator inhibitor-1(PAI-1) in lung tissue. A blood routine analyzer was used to measure inflammatory immune cell levels in the blood. Enzyme-linked immunosorbent assay(ELISA) was used to detect the expression levels of P-selectin and thromboxane A2(TXA2) in plasma. The results showed that, compared with the NC group, right heart hypertrophy index, right ventricular free wall thickness, right heart internal diameter, partial carbon dioxide pressure(PaCO_2), apoptosis in cardiopulmonary tissue, and ROS levels were significantly increased in the M group. In contrast, the ratio of pulmonary blood flow acceleration time(PAT)/ejection time(PET), right cardiac output, change rate of right ventricular systolic area, systolic displacement of the tricuspid ring, oxygen partial pressure(PaO_2), and blood oxygen saturation(SaO_2) were significantly decreased in the M group. After administration of the total extract of A. sylvestris, right heart function and blood gas levels were significantly improved, while apoptosis in cardiopulmonary tissue and ROS levels significantly decreased. Further testing revealed that the total extract of A. sylvestris significantly decreased the levels of interleukin-1β(IL-1β), interleukin-6(IL-6), and PAI-1 proteins in lung tissue, while increasing the expression of t-PA. Additionally, the extract reduced the levels of inflammatory cells such as leukocytes, lymphocytes, granulocytes, and monocytes in the blood, as well as the levels of P-selectin and TXA2 in plasma. Metabolomics results showed that the total extract of A. sylvestris significantly affected metabolic pathways, including arginine biosynthesis, tyrosine metabolism, and taurine and hypotaurine metabolism. In conclusion, the total extract of A. sylvestris may exert an anti-pulmonary hypertension effect by inhibiting the TGF-β1/Smad3 signaling pathway, thereby alleviating immune-inflammatory responses and thrombosis.
Animals
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Male
;
Smad3 Protein/metabolism*
;
Transforming Growth Factor beta1/metabolism*
;
Rats, Sprague-Dawley
;
Rats
;
Signal Transduction/drug effects*
;
Hypertension, Pulmonary/genetics*
;
Thrombosis/immunology*
;
Drugs, Chinese Herbal/administration & dosage*
;
Humans
;
Apoptosis/drug effects*
3.Application and research progress of artificial intelligence in the assessment of subsolid nodules
Fei LI ; Zhen BAI ; Jin-Long LIU ; Dan-Yang SU ; Shen-Yu YANG ; Yuan-Bo MA ; Ya-Man LI ; Yu-Fang DU ; Xiao-Peng YANG
Medical Journal of Chinese People's Liberation Army 2025;50(10):1243-1249
Lung cancer has the highest incidence and mortality among malignant tumors in China.Persistent subsolid nodules(SSNs)are closely associated with early-stage lung adenocarcinoma.Artificial intelligence(AI),as an emerging technology,is capable of performing in-depth analysis of large-scale imaging data through autonomous learning and possesses the ability to predict outcomes from new data,demonstrating great potential and application prospects in the assessment of SSNs.AI can not only effectively assist radiologists in diagnosis and treatment,but also improve work efficiency while reducing misdiagnosis and missed diagnosis rates.This review summarizes the recent applications and research progress of AI in the assessment of SSNs,to provide new insights for the diagnosis and treatment of SSNs.
4.Transcutaneous auricular vagus nerve stimulation regulates functional connectivity of thalamic subregions in patients with premenstrual syndrome
Ruijing SUN ; Yinqi LAI ; Ya CHEN ; Yuejuan WU ; Zhen LIU ; Qingping ZHANG ; Ziyan LAI ; Gaoxiong DUAN ; Yan ZHANG ; Shanshan LI ; Yuanyuan OU ; Sijing TUO ; Hui ZHOU ; Rongcai WU ; Zhizhong CHEN ; Demao DENG
Chinese Journal of Radiology 2025;59(12):1384-1392
Objective:To investigate the regulatory effects of transcutaneous auricular vagus nerve stimulation (taVNS) on functional connectivity (FC) of thalamic subregions in patients with premenstrual syndrome (PMS).Methods:This study was a cross-sectional investigation. Clinical, laboratory, and imaging data were retrospectively collected from 56 PMS patients (PMS group) and 66 healthy controls (control group) recruited from various universities and hospitals in Nanning between November 2021 and June 2024. Resting-state functional MRI (fMRI) data and fMRI data during taVNS immediate stimulation (2 Hz, 25 Hz) were acquired from subjects during their late luteal phase. Using thalamic subregions (anterior thalamic nucleus, lateral nucleus, ventral nucleus, medial nucleus, central nucleus, posterior nucleus) as seeds, two-sample t-tests or paired t-tests were employed to analyze alterations in thalamic subregion FC in PMS patients and the regulatory effects of taVNS on these changes. Independent samples t-test were used to compare the differences in clinical and laboratory indicators between the PMS group and the control group. The relationship between taVNS regulation of thalamic subregion FC in PMS patients and thalamic internal functional connectivity were analyzed using mediation effect analysis. Results:Compared to the control group, patients in the PMS group showed increased scores on the Daily Record of Severity of Problems, Pittsburgh Sleep Quality Index, Self-Rating Anxiety Scale, Self-Rating Depression Scale, Hamilton Anxiety Rating Scale 17, and Hamilton Depression Rating Scale 14 during the late luteal phase ( P<0.05). At baseline, PMS patients exhibited higher FC between the left thalamic lateral nucleus and the left insula, and lower FC between the left medial nucleus, posterior nucleus, and ventral nucleus of the thalamus and the right middle frontal gyrus (MFG) compared to the control group (GRF corrected, voxel-level P<0.001, cluster-level P<0.05). During 2 Hz taVNS immediate stimulation in PMS group, FC between the left thalamic medial nucleus, posterior nucleus, ventral nucleus and the right MFG, as well as the FC between the left thalamic ventral nucleu and the left MFG increased compared to baseline levels; meanwhile, FC between the left thalamic posterior nucleus, ventral nucleus and the left insula decreased compared to baseline levels (GRF corrected, voxel-level P<0.001, cluster-level P<0.05). During 25 Hz taVNS immediate stimulation, the FC between the left thalamic ventral nucleus and the right MFG decreased compared to the baseline level (GRF corrected, voxel-level P<0.001, cluster-level P<0.05). Mediation effect analysis showed that the FC between the left thalamic posterior nucleus and the left lateral nucleus mediated part of the association between the FC of the left lateral thalamic nucleus-left insula and the FC of the left ventral thalamic nucleus-left putamen/insula; there were significant direct effects between the FC of the left lateral thalamic nucleus-the left posterior nucleus and FC of the left lateral thalamic nucleus-the left insula, as well as between the FC of the left ventral thalamic nucleus-the left MFG and FC of the left ventral thalamic nucleus-the right MFG. Conclusions:taVNS can modulate abnormal FC of the left thalamic subregions in PMS patients, restoring it toward normalization. The regulatory effects of 2 Hz stimulation are more pronounced than those of 25 Hz stimulation. This modulation primarily operates through two pathways: the left thalamic lateral nucleus-left insula-left thalamic ventral nucleus pathway and the left MFG-left thalamic ventral nucleus-right MFG.
5.Effects of Modified Baitouweng Decoction and Lizhong Decoction on the improvement of mouse ulcerative colitis through autophagy regulation via AMPK/mTOR/p70S6K signaling pathway
Ya-fen ZHANG ; Zhen-kui ZUO ; Hong-lei JIAN ; Lin WANG ; Tian-rui LIU ; Lan-xin REN
Chinese Traditional Patent Medicine 2025;47(7):2198-2205
AIM To investigate the effects of Modified Baitouweng Decoction and Lizhong Decoction on mouse ulcerative colitis(UC).METHODS The mouse model of UC was established by 3%dextran sulfate sodium(DSS)induction.The C57BL/6 mice were randomly divided into the blank group,the model group,the low,medium and high dose Modified Baitouweng Decoction and Lizhong Decoction groups(3,6,12 g/kg),and sulfasalazine group(300 mg/kg),for 7 days gavage of the appropriate drugs,with 10 mice in each group.The mice had their disease activity index(DAI)and colonic mucosal damage index(CMDI)calculated;their colonic length and unit colonic weight measured;their histopathologic changes of colon observed by HE;their colonic ROS,MDA levels and GSH-Px,SOD activities detected by superoxide anion fluorescent probes and kits;their colonic levels of TNF-α,IL-6 and IL-1β detected by ELISA;their colonic LC3 expression detected by immunofluorescence method;and their colonic AMPK,mTOR and p70S6K protein expressions detected by Western blot method.RESULTS Compared with the blank group,the model group displayed significantly higher DAI score,CMDI score,unit colon weight,pathology score,ROS and MDA content,TNF-α,IL-6,and IL-1β levels,and mTOR and p70S6K protein expression(P<0.01);and significantly lower colon length,GSH-Px and SOD activity,LC3 level,and phosphorylated AMPK protein expression(P<0.01).Compared with the model group,the groups intervened with Modified Baitouweng Decoction and Lizhong Decoction or sulfasalazine shared decreased DAI score,CMDI score,unit colon mass,pathology score,ROS,MDA,TNF-α,IL-6,IL-1β levels,mTOR,p70S6K protein expressions(P<0.01);and significantly improved symptomsin terms of the elevated colonic length,GSH-Px,SOD activities,LC3 level,AMPK protein expression(P<0.01).CONCLUSION Modified Baitouweng Decoction and Lizhong Decoction may attenuate inflammatory response and oxidative damage in UC mouse models via AMPK/mTOR/p70S6K signaling pathway.
6.The Valvular Heart Disease-specific Age-adjusted Comorbidity Index (VHD-ACI) score in patients with moderate or severe valvular heart disease.
Mu-Rong XIE ; Bin ZHANG ; Yun-Qing YE ; Zhe LI ; Qing-Rong LIU ; Zhen-Yan ZHAO ; Jun-Xing LV ; De-Jing FENG ; Qing-Hao ZHAO ; Hai-Tong ZHANG ; Zhen-Ya DUAN ; Bin-Cheng WANG ; Shuai GUO ; Yan-Yan ZHAO ; Run-Lin GAO ; Hai-Yan XU ; Yong-Jian WU
Journal of Geriatric Cardiology 2025;22(9):759-774
BACKGROUND:
Based on the China-VHD database, this study sought to develop and validate a Valvular Heart Disease- specific Age-adjusted Comorbidity Index (VHD-ACI) for predicting mortality risk in patients with VHD.
METHODS & RESULTS:
The China-VHD study was a nationwide, multi-centre multi-centre cohort study enrolling 13,917 patients with moderate or severe VHD across 46 medical centres in China between April-June 2018. After excluding cases with missing key variables, 11,459 patients were retained for final analysis. The primary endpoint was 2-year all-cause mortality, with 941 deaths (10.0%) observed during follow-up. The VHD-ACI was derived after identifying 13 independent mortality predictors: cardiomyopathy, myocardial infarction, chronic obstructive pulmonary disease, pulmonary artery hypertension, low body weight, anaemia, hypoalbuminaemia, renal insufficiency, moderate/severe hepatic dysfunction, heart failure, cancer, NYHA functional class and age. The index exhibited good discrimination (AUC, 0.79) and calibration (Brier score, 0.062) in the total cohort, outperforming both EuroSCORE II and ACCI (P < 0.001 for comparison). Internal validation through 100 bootstrap iterations yielded a C statistic of 0.694 (95% CI: 0.665-0.723) for 2-year mortality prediction. VHD-ACI scores, as a continuous variable (VHD-ACI score: adjusted HR (95% CI): 1.263 (1.245-1.282), P < 0.001) or categorized using thresholds determined by the Yoden index (VHD-ACI ≥ 9 vs. < 9, adjusted HR (95% CI): 6.216 (5.378-7.184), P < 0.001), were independently associated with mortality. The prognostic performance remained consistent across all VHD subtypes (aortic stenosis, aortic regurgitation, mitral stenosis, mitral regurgitation, tricuspid valve disease, mixed aortic/mitral valve disease and multiple VHD), and clinical subgroups stratified by therapeutic strategy, LVEF status (preserved vs. reduced), disease severity and etiology.
CONCLUSION
The VHD-ACI is a simple 13-comorbidity algorithm for the prediction of mortality in VHD patients and providing a simple and rapid tool for risk stratification.
7.Transcutaneous auricular vagus nerve stimulation regulates functional connectivity of thalamic subregions in patients with premenstrual syndrome
Ruijing SUN ; Yinqi LAI ; Ya CHEN ; Yuejuan WU ; Zhen LIU ; Qingping ZHANG ; Ziyan LAI ; Gaoxiong DUAN ; Yan ZHANG ; Shanshan LI ; Yuanyuan OU ; Sijing TUO ; Hui ZHOU ; Rongcai WU ; Zhizhong CHEN ; Demao DENG
Chinese Journal of Radiology 2025;59(12):1384-1392
Objective:To investigate the regulatory effects of transcutaneous auricular vagus nerve stimulation (taVNS) on functional connectivity (FC) of thalamic subregions in patients with premenstrual syndrome (PMS).Methods:This study was a cross-sectional investigation. Clinical, laboratory, and imaging data were retrospectively collected from 56 PMS patients (PMS group) and 66 healthy controls (control group) recruited from various universities and hospitals in Nanning between November 2021 and June 2024. Resting-state functional MRI (fMRI) data and fMRI data during taVNS immediate stimulation (2 Hz, 25 Hz) were acquired from subjects during their late luteal phase. Using thalamic subregions (anterior thalamic nucleus, lateral nucleus, ventral nucleus, medial nucleus, central nucleus, posterior nucleus) as seeds, two-sample t-tests or paired t-tests were employed to analyze alterations in thalamic subregion FC in PMS patients and the regulatory effects of taVNS on these changes. Independent samples t-test were used to compare the differences in clinical and laboratory indicators between the PMS group and the control group. The relationship between taVNS regulation of thalamic subregion FC in PMS patients and thalamic internal functional connectivity were analyzed using mediation effect analysis. Results:Compared to the control group, patients in the PMS group showed increased scores on the Daily Record of Severity of Problems, Pittsburgh Sleep Quality Index, Self-Rating Anxiety Scale, Self-Rating Depression Scale, Hamilton Anxiety Rating Scale 17, and Hamilton Depression Rating Scale 14 during the late luteal phase ( P<0.05). At baseline, PMS patients exhibited higher FC between the left thalamic lateral nucleus and the left insula, and lower FC between the left medial nucleus, posterior nucleus, and ventral nucleus of the thalamus and the right middle frontal gyrus (MFG) compared to the control group (GRF corrected, voxel-level P<0.001, cluster-level P<0.05). During 2 Hz taVNS immediate stimulation in PMS group, FC between the left thalamic medial nucleus, posterior nucleus, ventral nucleus and the right MFG, as well as the FC between the left thalamic ventral nucleu and the left MFG increased compared to baseline levels; meanwhile, FC between the left thalamic posterior nucleus, ventral nucleus and the left insula decreased compared to baseline levels (GRF corrected, voxel-level P<0.001, cluster-level P<0.05). During 25 Hz taVNS immediate stimulation, the FC between the left thalamic ventral nucleus and the right MFG decreased compared to the baseline level (GRF corrected, voxel-level P<0.001, cluster-level P<0.05). Mediation effect analysis showed that the FC between the left thalamic posterior nucleus and the left lateral nucleus mediated part of the association between the FC of the left lateral thalamic nucleus-left insula and the FC of the left ventral thalamic nucleus-left putamen/insula; there were significant direct effects between the FC of the left lateral thalamic nucleus-the left posterior nucleus and FC of the left lateral thalamic nucleus-the left insula, as well as between the FC of the left ventral thalamic nucleus-the left MFG and FC of the left ventral thalamic nucleus-the right MFG. Conclusions:taVNS can modulate abnormal FC of the left thalamic subregions in PMS patients, restoring it toward normalization. The regulatory effects of 2 Hz stimulation are more pronounced than those of 25 Hz stimulation. This modulation primarily operates through two pathways: the left thalamic lateral nucleus-left insula-left thalamic ventral nucleus pathway and the left MFG-left thalamic ventral nucleus-right MFG.
8.Effects of Modified Baitouweng Decoction and Lizhong Decoction on the improvement of mouse ulcerative colitis through autophagy regulation via AMPK/mTOR/p70S6K signaling pathway
Ya-fen ZHANG ; Zhen-kui ZUO ; Hong-lei JIAN ; Lin WANG ; Tian-rui LIU ; Lan-xin REN
Chinese Traditional Patent Medicine 2025;47(7):2198-2205
AIM To investigate the effects of Modified Baitouweng Decoction and Lizhong Decoction on mouse ulcerative colitis(UC).METHODS The mouse model of UC was established by 3%dextran sulfate sodium(DSS)induction.The C57BL/6 mice were randomly divided into the blank group,the model group,the low,medium and high dose Modified Baitouweng Decoction and Lizhong Decoction groups(3,6,12 g/kg),and sulfasalazine group(300 mg/kg),for 7 days gavage of the appropriate drugs,with 10 mice in each group.The mice had their disease activity index(DAI)and colonic mucosal damage index(CMDI)calculated;their colonic length and unit colonic weight measured;their histopathologic changes of colon observed by HE;their colonic ROS,MDA levels and GSH-Px,SOD activities detected by superoxide anion fluorescent probes and kits;their colonic levels of TNF-α,IL-6 and IL-1β detected by ELISA;their colonic LC3 expression detected by immunofluorescence method;and their colonic AMPK,mTOR and p70S6K protein expressions detected by Western blot method.RESULTS Compared with the blank group,the model group displayed significantly higher DAI score,CMDI score,unit colon weight,pathology score,ROS and MDA content,TNF-α,IL-6,and IL-1β levels,and mTOR and p70S6K protein expression(P<0.01);and significantly lower colon length,GSH-Px and SOD activity,LC3 level,and phosphorylated AMPK protein expression(P<0.01).Compared with the model group,the groups intervened with Modified Baitouweng Decoction and Lizhong Decoction or sulfasalazine shared decreased DAI score,CMDI score,unit colon mass,pathology score,ROS,MDA,TNF-α,IL-6,IL-1β levels,mTOR,p70S6K protein expressions(P<0.01);and significantly improved symptomsin terms of the elevated colonic length,GSH-Px,SOD activities,LC3 level,AMPK protein expression(P<0.01).CONCLUSION Modified Baitouweng Decoction and Lizhong Decoction may attenuate inflammatory response and oxidative damage in UC mouse models via AMPK/mTOR/p70S6K signaling pathway.
9.Clinical trial of Morinda officinalis oligosaccharides in the continuation treatment of adults with mild and moderate depression
Shu-Zhe ZHOU ; Zu-Cheng HAN ; Xiu-Zhen WANG ; Yan-Qing CHEN ; Ya-Ling HU ; Xue-Qin YU ; Bin-Hong WANG ; Guo-Zhen FAN ; Hong SANG ; Ying HAI ; Zhi-Jie JIA ; Zhan-Min WANG ; Yan WEI ; Jian-Guo ZHU ; Xue-Qin SONG ; Zhi-Dong LIU ; Li KUANG ; Hong-Ming WANG ; Feng TIAN ; Yu-Xin LI ; Ling ZHANG ; Hai LIN ; Bin WU ; Chao-Ying WANG ; Chang LIU ; Jia-Fan SUN ; Shao-Xiao YAN ; Jun LIU ; Shou-Fu XIE ; Mao-Sheng FANG ; Wei-Feng MI ; Hong-Yan ZHANG
The Chinese Journal of Clinical Pharmacology 2024;40(6):815-819
Objective To observe the efficacy and safety of Morinda officinalis oligosaccharides in the continuation treatment of mild and moderate depression.Methods An open,single-arm,multi-center design was adopted in our study.Adult patients with mild and moderate depression who had received acute treatment of Morinda officinalis oligosaccharides were enrolled and continue to receive Morinda officinalis oligosaccharides capsules for 24 weeks,the dose remained unchanged during continuation treatment.The remission rate,recurrence rate,recurrence time,and the change from baseline to endpoint of Hamilton Depression Scale(HAMD),Hamilton Anxiety Scale(HAMA),Clinical Global Impression-Severity(CGI-S)and Arizona Sexual Experience Scale(ASEX)were evaluated.The incidence of treatment-related adverse events was reported.Results The scores of HAMD-17 at baseline and after treatment were 6.60±1.87 and 5.85±4.18,scores of HAMA were 6.36±3.02 and 4.93±3.09,scores of CGI-S were 1.49±0.56 and 1.29±0.81,scores of ASEX were 15.92±4.72 and 15.57±5.26,with significant difference(P<0.05).After continuation treatment,the remission rate was 54.59%(202 cases/370 cases),and the recurrence rate was 6.49%(24 cases/370 cases),the recurrence time was(64.67±42.47)days.The incidence of treatment-related adverse events was 15.35%(64 cases/417 cases).Conclusion Morinda officinalis oligosaccharides capsules can be effectively used for the continuation treatment of mild and moderate depression,and are well tolerated and safe.
10.On-line Measurement of Styrene Secondary Organic Aerosol Using Synchrotron Radiation Vacuum Ultraviolet Photoionization Aerosol Mass Spectrometer
Ming-Qiang HUANG ; Xiao-Bin SHAN ; Liu-Si SHENG ; Zhen-Ya WANG ; Chang-Jin HU ; Xue-Jun GU ; Wei-Jun ZHANG
Chinese Journal of Analytical Chemistry 2024;52(8):1200-1210
Secondary organic aerosol(SOA)produced by photooxidation of styrene and other aromatic compounds is a major part of fine particles in urban atmosphere.In this study,the measurement of component and content of SOA formed from photooxidation of styrene in smog chamber using synchronous radiation vacuum-ultraviolet photoionization aerosol mass spectrometer(VUV-PIAMS)was conducted.Photoionization mass spectra of styrene SOA was detected by synchrotron radiation photon with 10.5 eV,and the proportion of main components was quantified based on the peak area of each ion peak.The photoionization efficiency curve of ion peak was obtained under synchrotron radiation photons in the range from 7.5 to 11.5 eV,and then the ionization potential was acquired for qualitative analysis of the component structure.The results showed that the photoionization mass spectra of styrene SOA mainly contained ion peaks at m/z 106,108,120 and 122,and the ionization potentials of each peak were(9.41±0.03)eV,(8.93±0.03)eV,(9.24±0.03)eV and(9.25±0.03)eV,respectively.Combined with quantum chemistry calculation and off-line measurement verification of infrared absorption spectra and electrospray ionization mass spectra,it was determined that benzaldehyde,benzyl alcohol,4-vinylphenol and benzoic acid were main components of styrene SOA,accounting for 32.5%,17.5%,25%and 15%of the measured components,respectively,and the generated quantity ratio was 13∶7∶10∶6.VUV-PIAMS could overcome the disadvantages of off-line method,and could on-line detect component and content of SOA,proving a useful tool to measure the chemical components and reveal the formation process of SOA particles.

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