AntDAS-DDA: A New Platform for Data-Dependent Acquisition Mode-Based Untargeted Metabolomic Profiling Analysis with Advantage of Recognizing Insource Fragment Ions to Improve Compound Identification.

Data-dependent acquisition (DDA) mode in ultra-high-performance liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS) can provide massive amounts of MS1 and MS/MS information of compounds in untargeted metabolomics and can thus facilitate compound identification greatly. In this work, we developed a new platform called AntDAS-DDA for the automatic processing of UHPLC-HRMS data sets acquired under the DDA mode. Several algorithms, including extracted ion chromatogram extraction, feature extraction, MS/MS spectrum construction, fragment ion identification, and MS1 spectrum construction, were developed within the platform. The performance of AntDAS-DDA was investigated comprehensively with a mixture of standard and complex plant data sets. Results suggested that features in complex sample matrices can be extracted effectively, and the constructed MS1 and MS/MS spectra can benefit in compound identification greatly. The efficiency of compound identification can be improved by about 20%. AntDAS-DDA can take full advantage of MS/MS information in multiple sample analyses and provide more MS/MS spectra than single sample analysis. A comparison with advanced data analysis tools indicated that AntDAS-DDA may be used as an alternative for routine UHPLC-HRMS-based untargeted metabolomics. AntDAS-DDA is freely available at http://www.pmdb.org.cn/antdasdda.

Histomorphological analysis of perfusion parameters and CNS lymphatic vessels in mice: an experimental method study.

To investigate the distribution and characteristics of lymphatic vessels within the central nervous system, we focus on the meninges of the spinal cord and brain parenchyma in mice. Additionally, we aim to provide experimental methods for obtaining optimal imaging and clear structures of lymphatic vessels, while optimizing the perfusion parameters to improve histomorphological quality. Male C57BL/6J mice were randomly divided into four groups, with each group assigned a specific perfusion parameter based on perfusion volumes and temperatures. Immunofluorescence staining of lymphatics and blood vessels was performed on both meningeal and the brain tissue samples. Statistical analysis was performed using one-way analysis of variance to compare the groups, and a significant level of P < 0.05 was considered statistically significant. Our study reports the presence of lymphatic vessels in the meninges of the spinal cord and brain parenchyma in mice. We highlight the crucial role of high perfusion volume of paraformaldehyde with low temperature in fixation for achieving optimal results. We provide experimental methods for obtaining optimal imaging and clear structures of lymphatic vessels in the meninges of the spinal cord and brain parenchyma in mice, which contribute to our understanding of the distribution and characteristics of lymphatic vessels within the central nervous system. Further research is warranted to explore the functional implications of these lymphatic vessels and their potential therapeutic significance in neurodegenerative and neuroinflammatory diseases.

Factors influencing willingness to participate in ophthalmic clinical trials and strategies for effective recruitment.

AIM: To explore the factors influencing individuals' willingness to participate in ophthalmic clinical trials. METHODS: A questionnaire survey was conducted from January to April 2021 among patients and their family members at Zhongshan Ophthalmic Center, Sun Yat-sen University, in Guangzhou, China. The survey gathered data on respondents' willingness, demographic and socioeconomic profiles, as well as their reasons and concerns regarding engagement in clinical trials. RESULTS: Of the 1078 residents surveyed (mean age 31.2±13.1y; 65.8% females) in Guangzhou, 749 (69.5%) expressed a willingness to participate in future ophthalmic clinical trials. Specific characteristics associated with greater willingness included a younger age, lower annual income, higher education, prior participation experience, previous ophthalmic treatment, and a better understanding of clinical trials. With the exception of age, these characteristics were significantly linked to a higher willingness. The primary barrier to participation, expressed by 64.8% of those willing and 54.4% of those unwilling, was "Uncertain efficacy". In terms of motivations, the willing group ranked "Better therapeutic benefits" (35.0%), "Professional monitoring" (34.3%), and "Trust in healthcare professionals" (33.1%) as their top three reasons, whereas the unwilling participants indicated "Full comprehension of the protocol" (46.2%) as the key facilitator. CONCLUSION: This study reveals a substantial willingness to participate in ophthalmic clinical trials and demonstrates the predictive role of demographic and socioeconomic factors. Variations in motivators and concerns between willing and unwilling participants highlight the significance of tailored recruitment strategies. Importantly, the need for and trust in healthcare professionals stand out as powerful motivations, underscoring the importance of enhancing physician-patient relationships, adopting patient-centered communication approaches, and addressing individualized needs to improve accrual rates.

[Reliability of antral follicle counts using transvaginal two- and three-dimensional sonography].

OBJECTIVE: To assess the interobserver reliability of antral follicle counts (AFC) using Real-time two-dimensional (2D) ultrasound and three-dimensional (3D) ultrasound. METHODS: Two observers conducted transvaginal ultrasound examinations in 51 subfertile women in the early follicular phase of the menstrual cycle. Antral follicles were counted using Real-time 2D ultrasound and the time taken was recorded. A 3D volume was then acquired from each ovary and stored for subsequent offline analysis using the multiplanar view. The time taken for each step was recorded and the total time was calculated. Intraclass correlation coefficients (ICC) and limits of agreement were used to assess the reliability. RESULTS: There was no difference in the mean antral follicle counts using Real-time 2D (18.63±11.39) and 3D (18.73±11.74) ultrasound. According to the ICC, there was a significantly higher interobserver reliability for counts made using 3D (mean, 0.994; 95% CI, 0.990-0.997) as compared with Real-time 2D ultrasound (mean, 0.979; 95% CI, 0.963-0.988), P<0.01. 3D ultrasound was also associated with narrower limits of agreement (-3.46, 3.35) than was 2D ultrasound (-6.78, 6.31). While the total time taken was significantly longer for the 3D technique [(204.0±53.0) s vs. (112.4±34.8) s, P<0.001], the time required for the actual ultrasound examination was significantly less [(48.0±7.5) s vs. (112.4±34.8) s, P<0.001]. CONCLUSION: 3D ultrasound significantly improves the interobserver reliability of antral follicle counts. While this is at the expense of time overall, the duration of the actual ultrasound examination and the patient exposure is significantly reduced using 3D compared with Real-time 2D ultrasound.

Geographical discrimination of Flos Trollii by GC-MS and UHPLC-HRMS-based untargeted metabolomics combined with chemometrics.

For centuries, Flos Trollii has been consumed as functional tea and a folk medicine in China's north and northwest zones. The quality of Flos Trollii highly depends on the producing zones. Unfortunately, few studies have been reported on the geographical discrimination of Flos Trollii. This work comprehensively investigated Flos Trollii compounds with an integration strategy combining gas chromatography-mass spectrometry (GC-MS) and ultrahigh-performance liquid chromatography-high resolution mass spectrometry (UHPLC-HRMS) with chemometrics to explore the differences between Flos Trollii obtained from various origins of China. About 71 volatile and 22 involatile markers were identified with GC-MS and UHPLC-HRMS, respectively. Geographical discrimination models were synthetically investigated based on the identified markers. The results indicated that the UHPLC-HRMS coupled with the fisher discrimination model provided the best prediction capability (>97%). This study provides a new solution for Flos Trollii discrimination.

A study of flavor variations during the flaxseed roasting procedure by developed real-time SPME GC-MS coupled with chemometrics.

Volatile compound variations during the roasting procedure play an essential role in the flaxseed-related product. In this work, we proposed a new strategy to high-throughput characterize the dynamic variations of flavors in flaxseed. Volatile compounds released at various roasting times were comprehensively investigated by a newly developed real-time solid-phase microextraction coupled with gas chromatography-mass spectrometry (GC-MS). Raw data files were analyzed by our advanced GC-MS data analysis software AntDAS-GCMS. Chemometric methods such as principal component analysis and partial least squares-discrimination analysis have realized the differences of samples with various roasting times. Finally, a total of 51 compounds from 11 aromas were accurately identified and confirmed with standards, and their variations as a function of roasting time were studied. In conclusion, we provided a new solution for the online monitoring of volatile compounds during the industrial roasting process.

A comparison of feature extraction capabilities of advanced UHPLC-HRMS data analysis tools in plant metabolomics.

Data analysis of ultrahigh performance liquid chromatography-high resolution mass spectrometry (UHPLC-HRMS) is an essential and time-consuming step in plant metabolomics and feature extraction is the fundamental step for current tools. Various methods lead to different feature extraction results in practical applications, which may puzzle users for selecting adequate data analysis tools to deal with collected data. In this work, we provide a comprehensive method evaluation for some advanced UHPLC-HRMS data analysis tools in plant metabolomics, including MS-DIAL, XCMS, MZmine, AntDAS, Progenesis QI, and Compound Discoverer. Both mixtures of standards and various complex plant matrices were specifically designed for evaluating the performances of the involved method in analyzing both targeted and untargeted metabolomics. Results indicated that AntDAS provide the most acceptable feature extraction, compound identification, and quantification results in targeted compound analysis. Concerning the complex plant dataset, both MS-DIAL and AntDAS can provide more reliable results than the others. The method comparison is maybe useful for the selection of suitable data analysis tools for users.

Using UHPLC-HRMS-based comprehensive strategy to efficiently and accurately screen and identify illegal additives in health-care foods.

Accurately and high-thoroughly screening illegal additives in health-care foods continues to be a challenging task in routine analysis for the ultrahigh performance liquid chromatography-high resolution mass spectrometry based techniques. In this work, we proposed a new strategy to identify additives in complex food matrices, which consists of both experimental design and advanced chemometric data analysis. At first, reliable features in the analyzed samples were screened based on a simple but efficient sample weighting design, and those related to illegal additives were screened with robust statistical analysis. After the MS1 in-source fragment ion identification, both MS1 and MS/MS spectra were constructed for each underlying compound, based on which illegal additives can be precisely identified. The performance of the developed strategy was demonstrated by using mixture and synthetic sample datasets, indicating an improvement of data analysis efficiency up to 70.3 %. Finally, the developed strategy was applied for the screening of unknown additives in 21 batches of commercially available health-care foods. Results indicated that at least 80 % of false-positive results can be reduced and 4 additives were screened and confirmed.

Long noncoding RNA MIR210HG is induced by hypoxia-inducible factor 1α and promotes cervical cancer progression.

Increasing evidence has indicated that long noncoding RNAs (lncRNAs) play essential roles in various types of cancer, especially the ability of tumor cells to adapt to hypoxia conditions. However, only a few of them have been experimentally validated in cervical squamous cell carcinoma (CSCC). In the current study, we identified a hypoxia-induced lncRNA MIR210HG was excessively expressed in CSCC tissues and regulated by human papillomavirus (HPV) type 16 E6 and E7 via hypoxia-inducible factor 1α (HIF-1α). Functional assays revealed the role of MIR210HG in promoting proliferation, migration and invasion of CSCC cells in vitro under normoxia as well as hypoxia conditions. Meanwhile, stable MIR210HG silencing dramatically repressed tumor growth and pulmonary metastasis in vivo. Mechanistically, the depletion of MIR210HG or HIF-1α decreased each other's expression level, while silencing MIR210HG or HIF-1α respectively downregulated the expression levels of phosphoglycerate kinase 1 (PGK1), one of key metabolic enzymes in the glycolysis pathway. Furthermore, decreased expression of PGK1 by HIF-1α knockdown was reversed through the overexpression of MIR210HG. Also, we demonstrated HIF-1α can activate the transcription of MIR210HG via binding its promoter. Taken together, these results expand our understanding of the cancer-associated functions of hypoxia-induced lncRNAs, and highlight MIR210HG forms a feedback loop with HIF-1α contributing to cervical carcinogenesis, with potential implications for therapeutic targeting.

A chemometric strategy to automatically screen selected ion monitoring ions for gas chromatography-mass spectrometry-based pseudotargeted metabolomics.

The pseudotargeted metabolomics based on gas chromatography-mass spectrometry (GC-MS) has the advantage of filtering out artifacts originating from sample treatment and accurately quantifying underlying compounds in the analyzed samples. However, this technique faces the problem of selecting high-quality selective ions for performing selected ion monitoring (SIM) on instruments. In this work, we proposed AntDAS-SIMOpt, an automatic untargeted strategy for SIM ion optimization that was accomplished on the basis of an experimental design combined with advanced chemometric algorithms. First, a group of diluted quality control samples was used to screen underlying compounds in samples automatically. Ions in each of the resolved mass spectrum were then evaluated by using the developed algorithms to identify the SIM ion. A Matlab graphical user interface (GUI) was designed to facilitate routine analysis, which can be obtained from http://www.pmdb.org.cn/antdassimopt. The performance of the developed strategy was comprehensively investigated by using standard and complex plant datasets. Results indicated that AntDAS-SIMOpt may be useful for GC-MS-based metabolomics.

Effect of electroacupuncture on cyclic adenosine monophosphate-protein kinase A-vanillic acid receptor subtype 1 of the transient receptor potential/PLK-protein kinase C-vanillic acid receptor subtype 1 of the transient receptor potential pathway based on RNA-seq analysis in prostate tissue in rats with chronic prostatitis/chronic pelvic pain syndrome.

Objective: To investigate the analgesic mechanism of electroacupuncture (EA) in rats with chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS). Methods: Thirty male SD rats were randomly divided into sham group, model group and EA group, with ten rats in each group. The CP/CPPS model was prepared by injecting 50 µL of complete Freund's adjuvant (CFA) into the ventral lobes of the prostate tissue, and the sham group was injected with the same dose of saline. After 14 days of modeling, EA was applied to Guanyuan (CV4), Zhongji (CV3), Sanyinjiao (SP6) and Huiyang (BL35) in the EA group. After four courses, H&E staining was performed to observe the prostate tissue morphology, transcriptome sequencing (RNA-Seq) was performed for each group, and the selected signaling pathways were verified by qRT-PCR. Results: The RNA-Seq analysis results suggested that the analgesic effect of EA on CP/CPPS may be achieved by regulating prostate gene expression, which may be related to multiple biological processes and signaling pathways. qRT-PCR results showed that the vanillic acid receptor subtype 1 of the transient receptor potential (TRPV1), phospholipase C (PLC), protein kinase C (PKC), cyclic adenosine monophosphate (cAMP), and protein kinase A (PKA) were all upregulated in the model group compared to the sham group (p < 0.01). Compared with the model group, TRPV1, PLC, PKC, cAMP, and PKA were all downregulated in the EA group (p < 0.05, p < 0.01). Conclusion: The analgesic mechanism of EA on CP/CPPS may be achieved through modulation of cAMP-PKA-TRPV1/PLC-PKC-TRPV1 signaling pathway.

Size modulation of MIL-125 nanocrystals to promote the catalytic performance towards oxidative desulfurization.

The Ti-based metal-organic framework (Ti-MOF) MIL-125 with tunable crystalline size in the range of ca. 50 nm to 1500 nm was synthesized by the coordination modulation method using trans-cinnamic acid (CA) as a modulator. The coordination modulation also induced hierarchical porosity and structure defects on the nanocrystals. A significant size-dependent catalytic activity towards the oxidative desulfurization (ODS) reaction was observed for these MIL-125 nanocrystals. In particular, the MIL-125 nanocrystals with a mean size of ca. 50 nm exhibit dramatically enhanced catalytic performance for the bulky sulfur compound 4,6-dimethyldibenzothiophene (4,6-DMDBT) compared to the microcrystals. It is demonstrated that the size modulation of MIL-125 is an effective approach to promote its performance for the catalysis of bulky molecules.

[Role of JNK signal transduction pathway in nonalcoholic fatty liver disease].

OBJECTIVE: To investigate the role of c-Jun N-terminal kinase (JNK) signal transduction pathway in the rats of nonalcoholic fatty liver disease (NAFLD). METHODS: Sixty four Sprague-Dawley rats were randomly divided into four groups: 8-week control group (NG8w), 12-week control group (NG12 w), 8-week high-fat diet (HG8w), and 12-week high-fat diet group (HG12w), with 16 rats in each group. Glucose infusion rate (GIR) was tested by euglycemic hyperinsulinemic clamp; aminotransferase (ALT), aspartate aminotransferase (AST), triglyceride (TG), total cholesterol (TC), free fatty acid (FFAs), fast insulin (FIns), tumor necrosis factor alpha (TNF alpha), superoxide dismutase (SOD) and malondialdehyde (MDA) were tested by biochemistry automatic analyzer or RIA; The expression of JNK1, insulin receptor substrate-1 (IRS-1), phospho-IRS-1 Ser307 (p-IRS-1 Ser307), Protein kinase B (PKB) and phospho-PKB Ser473 (p- PKB Ser473) were detected by Western blot. RESULTS: Compared to control group, body weight, liver index, serum levels of ALT, AST, TG, TC, FIns, FFAs, TNF alpha, and TC, TG FFAs, MDA in liver homogenates were increased, while the level of SOD, and GIR were decreased. The expression of JNK1 protein and p-IRS-1 Ser307 in liver tissue was up-regulated, while expression of p-PKB Ser473 was decreased (P < 0.05). A positive correlation was found between the expression intensity of JNK1 and IR (Pearson correlation: 0.718, P < 0.01). CONCLUSION: The high-fat could induce the expression of JNK1, which in turn modulates the phosphorylation of proteins in the insulin signaling pathway, and induces insulin resistant.

[Volatile Organic Compound Emission Characteristics of Furniture Manufacturing Enterprises and the Influence on the Atmospheric Environment].

The furniture manufacturing industry is a typical industry with high pollution, low added value, relatively outdated technology and low levels of pollution control. The process of furniture manufacturing uses a large number of paints and adhesives, which emit a great quantity of volatile organic compounds (VOCs). The furniture manufacturing industry is a key industry for the control of VOCs in China. The VOCs emission characteristics and environmental impact of the furniture manufacturing industry has been studied in this work, which could be helpful for the Chinese government when formulating VOCs pollution control policy for this industry. In this study, a typical furniture manufacturing enterprise was chosen as the object. The emission concentration level and source profile of VOCs in a typical enterprise was obtained, and an assessment of the environmental impact of furniture manufacturing was developed. The results showed that the concentration of VOCs in the workshop ranged from 9.18 to 181.58 mg·m-3, the concentration of VOCs in the stack was 30.64-155.94 mg·m-3, and the treatment efficiency was 7.43%-67.14%. The main species of VOCs in the workshop were aromatic hydrocarbons, esters, and aldehydes and ketones; the main species of VOCs in the stack are esters and aromatic hydrocarbons, followed by alkanes, and the main VOCs in the industry are sec-butyl acetate, toluene, m-xylene, methylal and ethylbenzene. The average ozone generation potential (OFP) of workshop and stack VOCs was 258.01 and 289.14 mg·m-3, respectively, and the average secondary organic aerosol generation potential (SOAFP) of workshop and stack VOCs was 148.66 and 165.31 mg·m-3, respectively. The most important contribution to the OFP and SOAFP in each emission sector is aromatic hydrocarbons. The OFP and SOAFP in the edge-sealing workshop are large and the VOCs should be controlled. The main malodorous substances at the shop boundary are sec-butyl acetate, m-xylene, butyl acetate, p-xylene, ethylbenzene, 1-ethyl-3-methylbenzene, o-xylene, and toluene; the VOCs at the factory boundary produce almost no odor pollution. Targeted enhanced control of aromatic hydrocarbons and esters should be adopted to achieve effective emission reduction of VOCs in furniture manufacturing.

[Scenario Analyses of the Volatile Organic Compound Emission Allowance and Allocation in the 13th Five-Year Period].

China implemented the emission allowance and allocation strategy in 2016 to achieve effective control of volatile organic compounds (VOCs). An inventory of VOCs emissions for 2015 and future emissions for 2020 were developed and predicted, respectively, using emission factors and regression analysis. The results showed that anthropogenic VOCs emission in 2015 was 31117.0 kt. VOCs emission in 2020 under the business-as-usual scenario is predicted to be 41737.2 kt, an increase of 34.13% from that in 2015. Based on the Outline of the 13th Five-Year Plan, a total amount control target and pollution reduction task of about 28005.3 kt and 13731.9 kt, respectively, were proposed. Additionally, three control scenarios, i.e., implementing VOCs emission reduction strategies in all the key areas, in all the key industries, and in the key industries of the key areas, were established for the 13th Five-Year Plan using a scenario analysis method. The results showed that some differences exist between the potential mitigation of VOCs emissions and the emission reduction target for the three control scenarios, it is difficult to realize the emission allowance target. It is necessary to devote greater efforts to control VOCs. Moreover, reducing emissions of VOCs by implementing large-scale control projects is recommended. Further, regulation of VOC emissions in key areas and industries should be emphasized.

[Emission Inventory of Anthropogenic VOCs in Jiangmen City].

Anthropogenic VOC emissions are classified into four sources:industrial, mobile, life, and agricultural. An anthropogenic VOC emission inventory in Jiangmen for 2014 was developed using both "top-down" and "bottom-up" emission factor methods, based on statistical survey data. The results showed that the total anthropogenic VOC emissions in Jiangmen were 75.09 kt. VOC emissions from the industrial, mobile, life, and agricultural sources were 41.37, 19.16, 11.07, and 3.50 kt, respectively, which contributed 55.09%, 25.51%, 14.74%, and 4.65% of the total anthropogenic VOC emissions. Motorcycle manufacturing, container manufacturing, coating, printing ink, manufacturing of paint and similar products, printing and packaging printing, plastics and rubber products, artificial leather manufacturing, leather tanning, burning of fossil fuels, manufacturing of basic chemical raw materials, electronics manufacturing, adhesives manufacturing, and furniture manufacturing are key industries in Jiangmen, each of which emit more than 1000 t of VOCs annually. The main emission sources in Pengjiang, Jianghai, and Heshan are industrial, which account for more than 50% of emissions in each of these districts, whereas the main emission sources in Enping and Taishan are agricultural. Districts and county-level cities will be able to achieve better emission reduction by using the local VOC inventory in the formulation of VOC emission reduction policies.

[Stench Sources and Impact Analysis in Automobile Making].

Volatile organic compounds (VOCs) are an important source of industrial stench. This study was aimed at sampling and analyzing the stench source and its impact on the sensitive spot residential areas, concentrating on certain automobile manufacturing enterprise. The odor concentration and VOCs species of each vent stack, plant boundary, and sensitive spot in the enterprise were determined for November 15 and 17, 2016 via qualitative and quantitative analysis using the triangle odor bag method and gas pre-concentration system-gas chromatography-mass spectra. The results show that the odor concentrations of all vent stacks in the original equipment manufacturing plant and the engine plant were below the criterion level, those of the plant boundaries in the engine plant were below the limits, and those of the plant boundaries and sensitive spots in the original equipment manufacturing plant exceeded the allowed standards. A total of 54 VOCs species were identified, including aromatics, halogenated compounds, alkanes, alkene, cycloalkanes, ketones, esters, ethers, alcohols, sulfur compounds, and oxygen ring compounds. Halogenated compounds were the most abundant VOCs species, followed by aromatics. As a result, aromatics and halogenated compounds are the representative odorants in automobile making. 1,3-Butadiene and ethyl toluene were selected to be the typical odorants of sensitive spots according to mass concentration, detector odor threshold, and threshold dilution multiples of characteristic VOCs species in sensitive spots. The results show that the majority of characteristic VOCs species were from paint composition through the qualitative analysis based on paint used in coating shops. 1,3-Butadiene, which contributed the most to odor pollution, excluding the impact of other emission sources on sensitive spots, originates from spraying and drying processes of coating shops in the original equipment manufacturer. It is recommended that the enterprise should adopt environmentally friendly paints with low VOCs components or RTO purification equipment with higher processing efficiency to reduce the impact of stench on the sensitive residential areas from automobile making.

[Reactivity-based Anthropogenic VOCs Emission Inventory in China].

A reactivity-based anthropogenic volatile organic compounds (VOCs) emission inventory in China in 2010 was developed on the basis of ozone formation potential (OFP), using the latest VOCs emission inventory, source profiles and maximum incremental reactivity (MIR) values. The results showed that the total anthropogenic OFP was 84187.61 kt in China in 2010, of which 6882.53 kt was from alkanes, 41496.92 kt from alkenes/alkynes, 32945.32 kt from aromatic hydrocarbons, 161.45 kt from halocarbons, and 2701.40 kt from oxygenated organics. The top 10 species in terms of OFP consisted of propene, ethene, m/p-xylene, toluene, 1-butene, o-xylene, 1,2,4-trimethyl benzene, 1,3-butadiene, m-ethyl toluene and ethyl benzene, contributing 63.95% to the total OFP but only 31.84% to the mass-based emission. Industrial sources accounted for the largest (49.29%) of the total OFP, followed by transportation sources (28.31%) and agricultural sources (22.40%). The key industrial sources with high reactivity were architectural decoration industry, oil refinery industry, storage and transport, machinery equipment industry, transport equipment industry and printing. Passenger cars, motorcycles and heavy duty vehicles were the major OFP sources of transportation. The two biomass burning sources were both the key OFP sources of agriculture. Shandong, Jiangsu, Guangdong, Zhejiang and Henan were the top five provinces with contributions of 39.65% of the total OFP in China. The reactivity-based emission inventory in this study would be of great significance for the formulation of reactivity-based ozone (O3) control strategies in China.