ObjectiveTo investigate the clinical effect of Ershen Zhenwu Decoction on chronic heart failure （CHF） due to heart-kidney Yang deficiency and blood stasis and its regulatory effects on miR-423-5p/Smad7/transforming growth factor-β₁ （TGF-β₁）/Smads axis and myocardial fibrosis indicators. MethodsOne hundred and fourteen patients with heart failure with reduced ejection fraction （HFrEF） and heart failure with mildly reduced ejection fraction （HFmrEF） were randomly allocated into a control group and an observation group. The control group was treated with dapagliflozin tablets， sacubitril-valsartan sodium tablets， metoprolol succinate， and spironolactone， and the observation group was treated with Ershen Zhenwu Decoction on the basis of the therapy in the control group. The course of treatment was 8 weeks in both groups. The 6-min walking distance， New York Heart Association （NYHA） heart function grade， Minnesota Living with Heart Failure Questionnaire （MLHFQ） score， N-terminal pro-B-type natriuretic peptide （NT-proBNP）， angiotensin Ⅱ （Ang Ⅱ）， left ventricular ejection fraction （LVEF）， left ventricular end-diastolic diameter （LVIDd）， left ventricular end-systolic diameter （LVIDs）， interventricular septum thickness at diastole （IVSd）， left ventricular end-diastolic posterior wall thickness （LVPWd）， left ventricular shortening fraction （FS）， miR-423-5p， Smad7， Smad2， Smad3， Smad4， TGF-β₁， Ang Ⅱ， type Ⅰ collagen （Col Ⅰ）， type Ⅲ collagen （Col Ⅲ）， mRNA levels of fibronectin （Fn） and α-smooth muscle actin （α-SMA） in the myocardial tissue were observed before and after treatment in both groups to evaluate the efficacy of cardiac function and drug safety. ResultsAfter treatment， both groups showed declined levels of NT-proBNP， Ang Ⅱ， miR-423-5p， Smad2， Smad3， Smad4， TGF-β₁， Col Ⅰ， Col Ⅲ， and mRNA levels of Fn and α-SMA （P0.05）， and the levels of the indicators above were lower in the observation group than in the control group （P0.05）. After treatment， the Smad7 level increased obviously in both groups （P0.05） and was higher in the observation group than in the control group （P0.05）. After treatment， both groups showed decreased MLHFQ scores and increased 6-min walking distance （P0.05）， and the observation group had lower MLHFQ score and longer 6-min walking distance than the control group （P0.05）. After treatment， the control group showed increased LVEF and FS （P0.05） and the observation group showcased decreased LVIDd and LVIDs and increased LVEF and FS （P0.05）. Moreover， the observation group had lower LVIDd and LVIDs （P0.05） and higher LVEF and FS （P0.05） than the control group. The total response rate of cardiac function in the observation group was 90.38% （47/52）， which was higher than that （70.59%， 36/51） in the control group （P0.05）. No adverse reactions associated with Ershen Zhenwu Decoction were observed during the study period. ConclusionErshen Zhenwu Decoction can improve the cardiac function， exercise tolerance， and quality of life， regulate neuroendocrine factors， and slow down/reverse myocardial remodeling in the patients with HFrEF and HFmrEF （syndrome of heart-kidney Yang deficiency and blood stasis by regulating the miR-423-5p/Smad7/TGF-β₁/Smads axis， inhibiting α-SMA and Fn expression， and alleviating myocardial fibrosis. It is worthy of further study.

ObjectiveTo investigate the clinical effect of Ershen Zhenwu Decoction on chronic heart failure （CHF） due to heart-kidney Yang deficiency and blood stasis and its regulatory effects on miR-423-5p/Smad7/transforming growth factor-β₁ （TGF-β₁）/Smads axis and myocardial fibrosis indicators. MethodsOne hundred and fourteen patients with heart failure with reduced ejection fraction （HFrEF） and heart failure with mildly reduced ejection fraction （HFmrEF） were randomly allocated into a control group and an observation group. The control group was treated with dapagliflozin tablets， sacubitril-valsartan sodium tablets， metoprolol succinate， and spironolactone， and the observation group was treated with Ershen Zhenwu Decoction on the basis of the therapy in the control group. The course of treatment was 8 weeks in both groups. The 6-min walking distance， New York Heart Association （NYHA） heart function grade， Minnesota Living with Heart Failure Questionnaire （MLHFQ） score， N-terminal pro-B-type natriuretic peptide （NT-proBNP）， angiotensin Ⅱ （Ang Ⅱ）， left ventricular ejection fraction （LVEF）， left ventricular end-diastolic diameter （LVIDd）， left ventricular end-systolic diameter （LVIDs）， interventricular septum thickness at diastole （IVSd）， left ventricular end-diastolic posterior wall thickness （LVPWd）， left ventricular shortening fraction （FS）， miR-423-5p， Smad7， Smad2， Smad3， Smad4， TGF-β₁， Ang Ⅱ， type Ⅰ collagen （Col Ⅰ）， type Ⅲ collagen （Col Ⅲ）， mRNA levels of fibronectin （Fn） and α-smooth muscle actin （α-SMA） in the myocardial tissue were observed before and after treatment in both groups to evaluate the efficacy of cardiac function and drug safety. ResultsAfter treatment， both groups showed declined levels of NT-proBNP， Ang Ⅱ， miR-423-5p， Smad2， Smad3， Smad4， TGF-β₁， Col Ⅰ， Col Ⅲ， and mRNA levels of Fn and α-SMA （P0.05）， and the levels of the indicators above were lower in the observation group than in the control group （P0.05）. After treatment， the Smad7 level increased obviously in both groups （P0.05） and was higher in the observation group than in the control group （P0.05）. After treatment， both groups showed decreased MLHFQ scores and increased 6-min walking distance （P0.05）， and the observation group had lower MLHFQ score and longer 6-min walking distance than the control group （P0.05）. After treatment， the control group showed increased LVEF and FS （P0.05） and the observation group showcased decreased LVIDd and LVIDs and increased LVEF and FS （P0.05）. Moreover， the observation group had lower LVIDd and LVIDs （P0.05） and higher LVEF and FS （P0.05） than the control group. The total response rate of cardiac function in the observation group was 90.38% （47/52）， which was higher than that （70.59%， 36/51） in the control group （P0.05）. No adverse reactions associated with Ershen Zhenwu Decoction were observed during the study period. ConclusionErshen Zhenwu Decoction can improve the cardiac function， exercise tolerance， and quality of life， regulate neuroendocrine factors， and slow down/reverse myocardial remodeling in the patients with HFrEF and HFmrEF （syndrome of heart-kidney Yang deficiency and blood stasis by regulating the miR-423-5p/Smad7/TGF-β₁/Smads axis， inhibiting α-SMA and Fn expression， and alleviating myocardial fibrosis. It is worthy of further study.

Objective: To fabricate a hydrogel loaded with inositol hexaphosphate-zinc and preliminarily evaluate its performance in self-mineralization and osteoinduction, thereby providing a theoretical basis for the development of bone regeneration materials. Methods: The hydrogel framework (designated DF0) was formed by copolymerizing methacryloyloxyethyltrimethylammonium chloride and four-armed poly(ethylene glycol) acrylate, followed by sequentially loading inositol hexaphosphate anions via electrostatic interaction and zinc ions via chelation. The hydrogel loaded only with inositol hexaphosphate anions was named DF1, while the co-loaded hydrogel was named DF2. The self-mineralization efficacy of the DF0 , DF1 and DF2 hydrogels was characterized using scanning electron microscopy, transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), and selected area electron diffraction (SAED). The biocompatibility was assessed via live/dead cell staining and a CCK-8 assay. The osteoinductive capacity of the DF0 , DF1 and DF2 hydrogels on MC3T3-E1 cells was assessed via alkaline phosphatase (ALP) and Alizarin Red S (ARS) staining. In the aforementioned cell experiments, cells cultured in standard medium served as the control group Results: The DF0, DF1, and DF2 hydrogels were successfully synthesized. Notably, DF1 and DF2 exhibited distinct self-mineralization within 6 days. Results from TEM, EDS, and SAED confirmed that the mineralization products were amorphous calcium phosphate in group DF1, and amorphous calciumzinc phosphate in group DF2. Biocompatibility tests revealed that none of the hydrogels (DF0, DF1, and DF2) adversely affected cell viability or proliferation. In osteogenic induction experiments, both ALP and ARS staining were intensified in the DF1 and DF2 groups, with the most profound staining observed in the DF2 group. Conclusion The developed inositol hexaphosphate-zinc hydrogel (DF2) demonstrates the dual capacity to generate calcium-phosphate compounds through self-mineralization while exhibiting excellent osteoinductive properties. This biocompatible, dual-promoting osteogenic hydrogel presents a novel strategy for bone regeneration.

Objective : To investigate the biomechanical effect of alveolar bone graft (ABG) resorption on the maxillary alveolar process under occlusal force in a patient with unilateral cleft lip and palate (UCLP) and provide evidence for the clinical application of ABG. Methods: A 3D finite element maxillary model of an 11-year-old female patient with UCLP was generated. The occlusal force was applied to six models with different ABG resorption, namely non-resorption, upper 1/3 resorption, upper 2/3 resorption, lower 1/3 resorption, lower 2/3 resorption, and upper&lower 1/3 resorption. The properties of structures in all models were set to be linear, elastic, and isotropic. The displacement and Von Mises stress of each reference node of the alveolar process were compared and analyzed. Results: Under occlusal force, the most significant displacement of the alveolar process was located in the anterior area, and it decreased gradually from anterior area to both sides in all groups. The displacement values of the alveolar process under cleft side lateral occlusion were as follows: non-resorption group < lower 2/3 resorption group < upper&lower 1/3 resorption group < lower 1/3 resorption group < upper 2/3 resorption group < upper 1/3 resorption group. The displacement values of the alveolar process under centric occlusion were as follows: non-resorption group < lower 1/3 resorption group < upper&lower 1/3 resorption group < upper 2/3 resorption group < lower 2/3 resorption group < upper 1/3 resorption group. The displacement values of the alveolar process under non-cleft side lateral occlusion were as follows: non-resorption group < lower 1/3 resorption group < upper 1/3 resorption group < lower 2/3 resorption group < upper&lower 1/3 resorption group < upper 2/3 resorption group. The stress was concentrated on the premolar area on the functional side of the alveolar process, followed by the canine and molar areas in all groups. The stress values of the alveolar process under cleft side lateral occlusion were as follows: non-resorption group < lower 2/3 resorption group < upper&lower 1/3 resorption group < upper 2/3 resorption group < lower 1/3 resorption group < upper 1/3 resorption group. The stress values of the alveolar process under centric occlusion were as follows: non-resorption group < upper 1/3 resorption group < lower 1/3 resorption group < lower 2/3 resorption group < upper&lower 1/3 resorption group < upper 2/3 resorption group. The stress values of the alveolar process under non-cleft side lateral occlusion were as follows: non-resorption group < lower 2/3 resorption group < upper&lower 1/3 resorption group < lower 1/3 resorption group < upper 2/3 resorption group < upper 1/3 resorption group. Under occlusal force, the displacement and stress of the alveolar process in the non-resorption model were significantly lower than those in other models. The displacement and stress of the alveolar process in the models with resorption in the lower area of the ABG were significantly lower than those in the models with resorption in the upper-middle areas of the ABG. Conclusion After unilateral complete cleft lip and palate bone grafting, the integrity and continuity of the middle and upper parts of the alveolar process bone grafting play a key role in the biomechanical status of the alveolar process. If bone resorption occurs in the above parts, bone grafting should be considered.

ObjectiveTo observe the effects of the Fuyuan Tongluo prescription （composed of Astragali Radix， Carthami Flos， Spatholobi Caulis， Liquidambaris Fructus， Lycopodii Herba， Centellae Herba， etc.） in the treatment of restenosis with collateral obstruction syndrome after interventional operation of lower limb arteriosclerosis obliterans， and its impact on the primary patency rate. MethodsA total of 88 patients with collateral obstruction syndrome after interventional surgery for lower limb arteriosclerosis obliterans were randomly divided into two groups. The control group （n₁=44） received dual antiplatelet therapy with aspirin and clopidogrel. The observation group （n₂=44） was treated with Fuyuan Tongluo prescription non-decocted granules in addition to aspirin and clopidogrel. Both groups received treatment for 24 weeks and were followed up for 36 weeks. The changes in primary patency rate， symptom scores， ankle-brachial index （ABI）， coagulation function， and inflammatory markers before and after treatment were compared between the two groups. ResultsFor primary patency rate， after 36 weeks of treatment， the observation group had a significantly better primary patency rate than the control group （χ²=4.14，P<0.05）. After 24 weeks of treatment， there was no significant difference in primary patency rate between the two groups. Clinical efficacy comparison： Based on symptom quantification scores， and using the Nimodipine method as a reference， the overall efficacy of the observation group was superior to that of the control group after 24 weeks of treatment （χ²=2.24，P<0.05）. ABI levels： The observation group had a higher ABI than the control group after 24 and 36 weeks of treatment （P<0.05）. Coagulation function indicators： After 24 and 36 weeks of treatment， D-dimer and fibrinogen levels in both groups were lower than before treatment （P<0.05）. Inflammatory markers： After 24 and 36 weeks of treatment， CRP levels in the observation group were lower than those in the control group （P<0.05）. There were no significant differences in white blood cell （WBC） and erythrocyte sedimentation rate （ESR） levels before and after treatment between the two groups. ConclusionAdding Fuyuan Tongluo prescription non-decocted granules to dual antiplatelet therapy can improve the primary patency rate of the affected vessels in patients with lower limb arteriosclerosis obliterans after interventional surgery. Longer use of Fuyuan Tongluo prescription can significantly improve clinical symptoms， demonstrating clinical application value.

ObjectiveTo observe the effects of the Fuyuan Tongluo prescription （composed of Astragali Radix， Carthami Flos， Spatholobi Caulis， Liquidambaris Fructus， Lycopodii Herba， Centellae Herba， etc.） in the treatment of restenosis with collateral obstruction syndrome after interventional operation of lower limb arteriosclerosis obliterans， and its impact on the primary patency rate. MethodsA total of 88 patients with collateral obstruction syndrome after interventional surgery for lower limb arteriosclerosis obliterans were randomly divided into two groups. The control group （n₁=44） received dual antiplatelet therapy with aspirin and clopidogrel. The observation group （n₂=44） was treated with Fuyuan Tongluo prescription non-decocted granules in addition to aspirin and clopidogrel. Both groups received treatment for 24 weeks and were followed up for 36 weeks. The changes in primary patency rate， symptom scores， ankle-brachial index （ABI）， coagulation function， and inflammatory markers before and after treatment were compared between the two groups. ResultsFor primary patency rate， after 36 weeks of treatment， the observation group had a significantly better primary patency rate than the control group （χ²=4.14，P<0.05）. After 24 weeks of treatment， there was no significant difference in primary patency rate between the two groups. Clinical efficacy comparison： Based on symptom quantification scores， and using the Nimodipine method as a reference， the overall efficacy of the observation group was superior to that of the control group after 24 weeks of treatment （χ²=2.24，P<0.05）. ABI levels： The observation group had a higher ABI than the control group after 24 and 36 weeks of treatment （P<0.05）. Coagulation function indicators： After 24 and 36 weeks of treatment， D-dimer and fibrinogen levels in both groups were lower than before treatment （P<0.05）. Inflammatory markers： After 24 and 36 weeks of treatment， CRP levels in the observation group were lower than those in the control group （P<0.05）. There were no significant differences in white blood cell （WBC） and erythrocyte sedimentation rate （ESR） levels before and after treatment between the two groups. ConclusionAdding Fuyuan Tongluo prescription non-decocted granules to dual antiplatelet therapy can improve the primary patency rate of the affected vessels in patients with lower limb arteriosclerosis obliterans after interventional surgery. Longer use of Fuyuan Tongluo prescription can significantly improve clinical symptoms， demonstrating clinical application value.

Objective : To investigate the effects of resveratrol(Res) on fibroblast-like synoviocytes(FLS) in patients with rheumatoid arthritis(RA), and to explore the possible mechanism of Res inhibiting the release of inflammatory factors from FLS. Methods : FLS from RA patients were culturedin vitroand treated with different concentrations of Res(0, 20, 40, 80, 160, 320 μmol/L). The viability of FLS cells was detected by CCK-8 assay after 12 and 24 h. The contents of inflammatory factor interleukin-6(IL-6) and tumor necrosis factor-α(TNF-α) in cell supernatant were detected by ELISA. The expression levels of cyclic guanosine monophosphate-adenosine monophosphate synthase(cGAS) and stimulator of interferon gene(STING) were measured by Western blot; After lentivirus infection with FLS caused the cells to overexpress cGAS, the cells were divided into Control group(blank control), cGAS group(cGAS overexpression), Res+cGAS group(Res 160 μmol/L+cGAS overexpression) and Res group(Res 160 μmol/L). The expression level of STING protein in cells of each group was determined by Western blot, the viability of FLS cells in each group was detected by CCK-8, and the contents of inflammatory factor IL-6 and TNF-α in the supernatant of cells of each group were detected by ELISA method. Results : The results of CCK-8 experiment showed that under 40, 80, 160 μmol/L Res treatment, FLS viability decreased significantly after 24 h compared with blank control group(P<0.01). ELISA results showed that the contents of IL-6 and TNF-α in cell supernatant were also significantly decreased after treatment with Res of 40, 80 and 160 μmol/L(P<0.01). Meanwhile, Western blot results showed that Res could significantly decrease the protein expression levels of STING and cGAS in FLS cells after treatment of 40, 80 and 160 μmol/L(P<0.05,P<0.01). Compared with the Control group, the expression level of STING protein in FLS increased after overexpression of cGAS(P<0.05); compared with the Res group, the content of inflammatory factors in the supernatant of FLS and the expression level of STING protein in FLS significantly increased after overexpression of cGAS(P<0.01,P<0.05). Conclusion The appropriate concentration of Res can inhibit the release of inflammatory cytokines in FLS cells, which may be related to the blocking of cGAS-STING signaling pathway.

Objective: To explore the relative importance of different food attributes and levels in food decision making of school aged children, and to understand their meal preferences, so as to provide the evidence for formulating precise intervention strategies for dietary behaviours of school aged children. Methods: From May to June 2024, a total of 854 children aged 11 to 15 years old were selected from 2 middle schools (each school in urban and rural areas) in both Hubei Province and Anhui Province by stratified cluster random sampling method to conduct a D-optimal discrete choice experiment. The mixed Logit model was used to analyze children s preference for meal attributes and different levels, and to calculate the relative importance (RI) of attributes and willingness to pay (WTP) in meal choices. Results: The included five food attributes had statistical significance on meal choice of school aged children ( P <0.05). The relative importance of food attributes affecting the meal choices of school aged children in descending order were dining mode ( RI =31.26%), food varieties ( RI =30.56%), cooking method( RI =23.84%), taste( RI =8.06%) and price ( RI =6.27%). Among them, school aged children preferred home cooked meals ( β =0.74) (WTP=86.3 yuan),varied foods(grain/tubers+vegetables+fish, meat, eggs and beans) ( β =0.61) (WTP=71.9 yuan), fried/roasted cooking ( β =0.51) and spicy taste ( β =0.33).Price was negatively correlated with meal choices( β =-0.01) ( P <0.05). Based on residential area and body mass index (BMI), the stratified analysis showed that dining mode was highest in the relative importance for rural children with overweight and obese children ( RI =31.28%,34.17%), both of whom preferred home cooked meals ( β =0.76, 0.91), and meals containing fish, meat, eggs and beans with grain/tubers or grain/tubers and vegetables in terms of food choice (area: β =0.53, 0.53 ; BMI: β =0.55, 0.56) ( P <0.05). Conclusions School aged children have different preferences for different attributes of meals. The quality of school meals should be improved,the cost of buying healthy meals should be reduced,targeted family health education should be carried out,and healthy cooking methods should be advocated.

Objective: To explore the longitudinal associations between dietary macronutrients and lung function in schoolaged children, so as to provide the nutritional research evidence for promoting children s lung health. Methods: In November 2021, two primary schools located in Chengdu, Sichuan Province were selected from the Southwest China Childhood Nutrition and Growth (SCCNG) cohort by a stratified cluster random sampling method, enrolling a total of 1 112 school aged children aged 8 to 13 years. At baseline, the dietary and sociodemographic characteristics of the children were assessed. One year later, the forced vital capacity (FVC) of the children was measured and converted into Z scores (FVC- Z ), while the vital capacity index (VCI) was also calculated. Generalized linear regression analysis was employed to examine the associations between dietary macronutrients and lung function, considering interactions with gender and age, followed by stratified analysis. Results: After adjusting for confounding factors, the analysis results of the generalized linear regression model showed that the carbohydrate energy ratio was negatively correlated with FVC- Z ( β =-0.02) and VCI ( β =-0.16), while the fat energy ratio showed a positive correlation with FVC- Z ( β =0.03) and VCI ( β =0.23) ( P <0.05). The protein energy ratio was positively correlated with FVC- Z ( β =0.09) and VCI ( β =0.60) specifically in girls ( P <0.05). Additionally, there was an interaction effect of age on the associations between macronutrients and lung function ( P <0.01); in children aged 8-9 and 10-11, the carbohydrate energy supply ratio was negatively correlated with FVC- Z ( β =-0.04, -0.03) and VCI ( β =-0.29, -0.21), and fat energy supply ratio was positively correlated with FVC- Z ( β =0.07, 0.05) and VCI ( β =0.46, 0.32) ( P <0.05). Conclusions There are age and sex differences in the association of dietary macronutrients with lung function, with a low carbohydrate, high fat diet promoting lung function in children. Additionally, protein intake appears to have a positive influence on the lung function of girls. The early school age period may represent a critical window for dietary interventions aimed at promoting lung health.

Background Polycyclic aromatic hydrocarbons (PAHs) are widely known atmospheric pollutants, which can cause serious harm to human body and ecological environment. Objective To analyze the concentrations and sources of PAHs in atmospheric PM_2.5 in Zhifu District and Longkou City during the heating period in Yantai. Methods Two monitoring sites in Zhifu District and Longkou City of Yantai were selected, and PM_2.5 sample collection was carried out from April 2023 to March 2024. Gas chromatography-mass spectrometry was applied to analyze the concentrations of PAHs in atmospheric PM_2.5 during the heating period (from November 2023 to March 2024) and the non-heating period (from April to October 2023). The concentrations of PAHs in the two periods were compared and the sources of PAHs during the heating period were analyzed by characteristic ratio method. Results During the heating period, the total concentration ranges of PAHs in atmospheric PM_2.5 at the monitoring sites in Zhifu District and Longkou City of Yantai were (1.59-23.70) ng·m⁻³ and (2.08-149.72) ng·m⁻³ respectively, and the medians (M) and the 25th and 75th percentiles (P₂₅, P₇₅) were 4.99 (2.61, 8.09) ng·m⁻³ and 15.46 (8.15, 29.05) ng·m⁻³ respectively. The PAHs concentrations in Longkou City were significantly higher than those in Zhifu District in all months (P<0.05). The highest median total concentrations of PAHs in both sites were reported in January (8.14 ng·m⁻³ and 81.56 ng·m⁻³ respectively). In the non-heating period, the M (P₂₅, P₇₅) of the total PAHs concentrations at the two sites were 1.59 (1.59, 2.78) ng·m⁻³ and 4.11 (2.94, 7.97) ng·m⁻³ respectively, much lower than those in the heating period (P<0.01). The order of composition of PAHs by ring number in PM_2.5 at both sites was 4-ring> 5-ring> 6-ring, with the 4-ring contributing the largest proportion (65.33% and 46.39% respectively). Fluoranthene had the highest concentration among PAHs at both sites, with concentrations M (P₂₅, P₇₅) of 1.29 (0.51, 1.78) ng·m⁻³ and 2.32 (1.30, 3.82) ng·m⁻³ respectively. The characteristic ratios of fluoranthene/(fluoranthene + pyrene), fluoranthene/pyrene, benzo[a]anthracene/(benzo[a]anthracene + chrysene), pyrene/benzo[a]pyrene, benzo[a]pyrene/(benzo[a]pyrene + chrysene), benzo[a]pyrene/benzo[g,h,i]pyrene, and indeno[1,2,3-c,d]pyrene/(indeno[1,2,3-c,d]pyrene + benzo[g,h,i]pyrene) in Zhifu District were 0.62, 1.65, 0.41, 4.48, 0.50, 0.93 and 0.47 respectively, and those in Longkou were 0.57, 1.35, 0.40, 2.89, 0.29, 0.79 and 0.47 respectively. The results showed that PAHs pollutants were generated by combination of coal combustion, vehicle exhaust emissions and gasoline combustion. Conclusion During the heating period in Yantai area, the total concentration of PAHs in atmospheric PM_2.5 is significantly higher than that in the non-heating period. Among them, during the heating period, the pollution level in Longkou City is significantly higher than that in Zhifu District. The local PAHs may be sourced from mixed pollution, and the main sources include gasoline, and coal combustion and vehicle exhaust emissions.