Objective To study the seasonal distribution characteristics of polycyclic aromatic hydrocarbons (PAHs) in PM_2.5 in Lianyungang City, and analyze the sources of PAHs pollution, and to evaluate the health risks of PAHs in different seasons. Methods PM2.5 samples were collected regularly from January 2019 to December 2023, and 16 types of PAHs were determined by HPLC. Kruskal-Wallis H test was used to compare the concentrations of PM2.5 and PAHs in different years and seasons. The source of PAHs was analyzed by characteristic ratio and principal component analysis (PCA). Health risks were assessed using the BaP equivalent method and the incremental lifetime cancer risk (ILCR) model. Results The annual exceedance rates of PM_2.5 and BaP in Lianyungang showed a decreasing trend from 2019 to 2023. PM_2.5, total PAHs and PAHs monomers (except Ace, Flu and Acy) all showed significant seasonal differences, with the highest concentration in winter (P<0.001). The average proportion of 4-ring PAHs was the highest and the average proportion of 2-ring PAHs was the lowest. The proportion of 5-6 ring PAHs was relatively high in winter and spring. PM2.5and PAHs were negatively correlated with temperature, relative humidity and precipitation, and were positively correlated with atmospheric pressure. PM_2.5 was negatively correlated with wind speed, while some PAHs monomers were positively correlated with wind speed. The characteristic ratio and PCA results showed that the main sources of PAHs in Lianyungang City were mixed sources of road dust and vehicle emissions, oil pollution sources and biomass combustion sources. The results of ILCR showed that the highest risk was found in adults, with males slightly higher than females. In Lianyungang, the maximum value of ILCR in winter was more than 10-6 in people over 9 years old. Conclusion The main sources of PAHs in PM_2.5 in Lianyungang City are mixed sources of road dust and vehicle emissions, oil pollution sources, and biomass combustion sources. Under the current exposure level of PAHs in PM_2.5, residents have a certain potential carcinogenic risk.

BACKGROUND:Congenital clubfoot mainly manifests as abnormal bone itself and abnormal cartilage development.The bone morphogenetic protein(BMP)/drosophila mothers against decapentaplegic protein(Smad)signaling pathway can direct the development of bone and cartilage during embryonic period,but its role in the field of clubfoot etiology has not been confirmed in animal experiments. OBJECTIVE:To explore the mechanism by which the BMP/Smad signaling pathway is involved in the regulation of foot and ankle chondroplasia in a rat congenital clubfoot model. METHODS:Sprague-Dawley rats at 10 days of gestation with the same growth condition were randomly divided into experimental and control groups.The experimental group was intragastrically given 135 mg/kg retinoic acid to make the clubfoot model,while the control group was given the same amount of vegetable oil.The fetal rats were taken out after 21 days of gestation by cesarean section.In the experimental group,the 27 of 41 fetal rats had clubfoot,with a deformity rate of 65.9%;in the control group,no clubfoot was observed in all the 36 fetuses.The ankles tissues of the rats were collected for hematoxylin-eosin staining.Western blot assay,RT-qPCR and immunohistochemistry were performed to detect the expression levels of Smad5 and P-Smad5,the core proteins of the BMP/Smad signaling pathway,as well as SP7 and Sox9,the downstream proteins of the BMP/Smad signaling pathway. RESULTS AND CONCLUSION:Compared with the control group,hematoxylin-eosin staining showed that the cartilage matrix in the foot and ankle tissues increased and the gap between the bones increased in the experimental group.Immunohistochemical findings showed that the expression levels of Smad5 and SP7 decreased in the experimental group,while the mRNA expression of Sox9 increased.RT-qPCR results showed that the mRNA expression of Smad5 and SP7 decreased,while the mRNA expression of Sox9 increased in the foot and ankle tissues of rats in the experimental group.Western blot results showed that P-Smad5/Smad5 expression and SP7 expression were decreased and Sox9 expression was increased in the ankle of rats in the experimental group.To conclude,the occurrence of cartilage abnormalities in the foot and ankle of the rat model of congenital clubfoot is associated with impaired transmission of the BMP/Smad signaling pathway.

Objective: To establish a method for determining the content of bear bile powder in Longze Xiongdan capsules with taursodeoxycholic acid（TUDCA） and taurchenodeoxycholic acid（TCDCA） as indexes.
Methods: HPLC series evaporation photodetector was adopted on Chrom Core AQ C₁₈ column(4.6 mm×250 mm, 5 μm), with the mobile phase comprising of acetonitrile ( A ) and 5 mmol·L^-1 ammonium acetate solution (B) in a gradient elution (0-40 min, 25%A; 40-50 min, 25%A→29%A; 50-80 min, 29%A; 80-100 min, 29%A→40%A) at the flow rate of 1.0 mL·min^-1. The column temperature was 30 ℃. The ELSD was used, of which the drift tube temperature was 110 ℃ and the flow rate of carrier gas（N₂） was 2.5 L·min^-1.
Results: In the ranges of 1.069-9.57 μg and 0.740 46-7.404 64 μg, logarithms of the injected amount of TUDCA and TCDCA presented good linear relationships with logarithms of the peak area, respectively. The RSDs of precision, repeatability and stability tests were all lower than 2.0%. At three concentration levels the recoveries of TUDCA and TCDCA were 95.2%-97.7% and 91.9%-95.9%, respectively. Samples of 42 batches showed that the contents of TUDCA and TCDCA were 0.18-0.43 and 0.10-0.44 mg·granule^-1, respectively.
Conclusion: This method can be used for the quality control of bear bile powder in Longze Xiongdan capsules, thus provides a scientific basis for improving its quality standard.

AIM: To observe the changes of nerve fiber thickness and vessel density in macula and optic disc following femtosecond laser-assisted and conventional phacoemulsification cataract surgery through optical coherence tomography angiography(OCTA).METHODS: A total of 65 cases(85 eyes)that diagnosed with age-related cataract and received surgery in Aier Eye Hospital(East of Chengdu)were included in this prospective nonrandomized controlled study. The patients were divided into two groups according to the surgery choice, with 23 cases(30 eyes)in femtosecond laser assisted group, and 42 cases(55 eyes)in traditional phacoemulsification group. OCTA was used to compare the changes in central macular thickness, thickness of nerve fiber layer in optic disc, vessel density and blood perfusion preoperatively, and at 1 d and 1 mo postoperatively.RESULTS: BCVA of patients in the two groups was significantly improved and IOP was significantly reduced at 1 mo postoperatively(all P<0.01). The macular nerve fiber layer thickness of the femtosecond laser-assisted group was increased at 1 d and 1 mo postoperatively(all P<0.05), while there was no statistical difference in the traditional phacoemulsification group before and after surgery(all P>0.05); there were significant differences in nerve fiber layer thickness in optic disc, vessel density and blood perfusion in both macula and optic disc of the traditional phacoemulsification group(all P<0.05), but there were no differences in the femtosecond laser assisted group(all P>0.05). Furthermore, there were no significant differences in foveal avascular zone area in the two groups of patients(all P>0.05).CONCLUSION: Femtosecond laser-assisted cataract surgery had less impact on retinal vessels.

Objective:To study the application of 3D printing technology in multi-center fenestrated/branched endovascular repair (F/B-EVAR) for endovascular repair of abdominal aortic diseases.Methods:From Feb 2018 to Mar 2023, The clinical and followup data of 316 cases of abdominal aortic lesions undergoing repair with F/B-EVAR at 69 medical centers nationwide using 3D printing technology to guide physician-modified stent graft were retrospectively analyzed.Results:The mean follow-up time of the patients was 23 months (2-60 months), and 24 cases were lost to follow up, the follow-up rate was 92.4% (292/316), the mean postoperative hospitalization time was (8.2±4.9) days. A total of 944 main abdominal branch arteries were reconstructed. Intraoperative reconstruction of 11 branches failed, with a success rate of 98.8% (933/944). Within 30 days after surgery, 8 patients died (2.5%), and 6 patients died during follow-up, a total of 14 patients died (4.4%). There were 11 cases (3.5%) of spinal cord ischemia and no patient suffered from permanent paraplegia. There were 19 patients (6.0%) with postoperative renal function injury. Internal leakage was found in 26 patients, and the rate of internal leakage was 8.2%.Conclusion:3D printing technology can accurately locate the location of branch arteries, simplifing the surgical process, shortening the learning curve , and improving clinical efficacy.

Objective:To review the risk factors for early and medium-term complications of fenestration-branch endovascular thoracic aortic repair (F/B-TEVAR) in patients with complex aortic arch disease.Methods:The clinical and follow-up data of 202 patients undergoing F/B-TEVAR treatment from Feb 2019 to Sep 2023 in these centers were retrospectively analyzed .Results:There were 46 cases suffering from postoperative complications (22.8%). The risk factors with statistical significance included aortic atherosclerotic plaque [ OR=2.843; 95% CI (1.4-5.6); P<0.01], aortic intramural thrombosis [ OR=2.358; 95% CI (1.2-4.6), P=0.011], the aortic dilatation [ OR=4.219; 95% CI (1.6-11.3), P<0.01], the history of stroke [ OR=2.088; 95% CI (1.1-4.1), P=0.032], smoking history [ OR=2.680; 95% CI: (1.3-5.5); P<0.01], duration of surgery [ OR=1.9; 95% CI: (1.2-2.9); P=0.042].While the application of 3D printing assistive technology [ OR=0.392; 95% CI: (0.2-0.9); P=0.048] was in a negative correlation with postoperative complication. Conclusions:The independent risk factors for complications after F/B-TVAR included aortic atherosclerotic plaque, aortic intramural thrombosis, the aortic dilatation, the history of stroke, smoking history,duration of surgery.The application of 3D printing technology can effectively reduce the complication rate.

Objective To investigate the age-related changes of biomechanical properties for humerus, femur and tibia in male rats and their application values in age estimation. Methods According to different weeks of age, 90 healthy male SD rats were divided into 2, 4, 6, 8, 17, 26, 52, 78 and 104-week groups with 10 rats in eachgroup. After the rats were executed by excessive anesthesia, humerus, femur, and tibia were separated and the attached soft tissues were removed. The length of the above-mentioned bones and the diameter of the middle section (compression site) were measured with vernier caliper, and the three-point bending test was conducted with electronic universal material testing machine to detect the ultimate load and displacement under ultimate load. Results There were significant differences in the ultimate load of humerus, femur and tibia among male rats in different age groups (P<0. 05). With the increase of week age, the ultimate loads of the humerus, femur and tibia increased first and then decreased, and reached the peak value in 52-week age group, showing a strong positive correlation with week age before 52 weeks ( r = 0. 884,0. 933,0. 929, P<0. 05). There was no significant difference in humerus and tibia. The displacement of femur under ultimate load was weakly positively correlated with week age (R= 0. 406,P<0. 05). The age prediction accuracy for automatic linear modeling of ultimate load for humerus, femur, tibia and three above-mentioned bones in rats before 52-week age was 78. 2% , 86. 8% , 84. 1% and 88. 3% , respectively. There was a strong positive correlation between the length of humerus, femur and tibia and the ultimate load (R= 0. 904, 0. 897, 0. 814, P<0. 05). The diameters of humerus, femur and tibia were strongly positively correlated with the ultimate load (R = 0. 759, 0. 814 and 0. 745, P<0. 05). Conclusions The ultimate loads of humerus, femur and tibia in male rats increased first and then decreased with age, and were positively correlated with age before 52 weeks, which could be used for age inference. The highest accuracy of age estimation was ultimate loads of three bones, followed by femur. The length/ middle diameter of humerus, femur and tibia were strongly positively correlated with the ultimate load.

Objective To investigate the effect of different optimization algorithms on accurate reconstruction of traffic accidents. Methods Non-dominated sorting genetic algorithm-II ( NSGA-II), neighborhood cultivation genetic algorithm (NCGA) and multi-objective particle swarm optimization (MOPSO) were used to optimize the multi-rigid body dynamic reconstruction of a real case. The effects of different optimization algorithms on convergence speed and optimal approximate solution were studied. The optimal initial impact parameters were simulated as boundary conditions of finite element method, and the simulated results were compared with the actual injuries. Results NCGA had a faster convergence speed and a better result in optimization process. The kinematic response of pedestrian vehicle collision reconstructed by the optimal approximate solution was consistent with the surveillance video. The prediction of craniocerebral injury was basically consistent with the cadaver examination. Conclusions The combination of optimization algorithm, rigid multibody and finite element method can complete the accurate reconstruction of traffic accidents and reduce the influence of human factors.

Objective:To analyze the impact of global budget on the medical flow treatment and fund allocation in a non-compact medical community based on the symbiosis theory, so as to provide references for relevant authorities to formulate policies for the medical community.Methods:Data on outpatient and emergency visits, discharges, and medical insurance fund usage of the leading hospital and primary medical and health institutions in a non-compact medical community were collected from the health information system of a certain city. The time range of the data spanned from January 2017 to December 2019. The total budget was implemented in April 2018. The symbiotic system of the non-compact medical community was analyzed based on the theory of symbiosis. Descriptive analysis and intermittent time series segmented regression model were used to analyze the changes in indexes related to the flow of medical treatment and fund allocation between the leading hospital and primary institutions under the global budget.Results:The non-compact medical community′s symbiotic system had developed a continuous symbiotic model in organization and an asymmetric reciprocal symbiotic model in behavior. From the perspective of medical treatment flow, the number of outpatient and emergency visits of leading hospital and primary institutions in the medical community showed an upward trend, with little change in the number of discharged patients from 2017 to 2019; The number of patients transferred by the leading hospital increased from 32 in 2017 to 87 in 2019. According to the analysis of the intermittent time series segmented regression model, after the implementation of global budget, the proportion of outpatient and emergency visits in leading hospital was decreased ( β3=-0.43, P<0.05), the proportion of outpatient and emergency visits in primary institutions was on the rise ( β3= 0.02, P<0.05). In terms of fund allocation, the share of health insurance fund of the leading hospital increased from 45.98% in 2017 to 46.51% in 2019, and the primary medical and health institutions decreased from 23.44% to 18.06%, as well as the ratio of per capita income of primary medical and health institutions to that of leading hospitals was decreased from 72.62% to 60.79%. Conclusions:Under the global budget, the outpatient and emergency medical treatment flow in a non-compact medical community had been optimized. However, there was an uneven distribution of funds among medical institutions at all levels. Thus it was recommended to continue to give full play to the positive incentive effect of the global budget, establish a scientific mechanism for distributing benefits, and strengthen supervision and management.

Objective:To understand the incentive effect and influencing factors of the current economic incentive policy for medical alliances in Longhua District of Shenzhen(the alliance for short) on doctors′ willingness to work at primary medical institutions(the primary for short) from the perspective of mental account, and to explore the economic incentive effect of different economic incentive distribution methods on doctors′ willingness to work at the primary.Methods:The questionnaire was designed based on mental account theory. Random sampling was made in November 2019 for a questionnaire survey among doctors in two district-level medical institutions of the alliance in Longhua District of Shenzhen. The purpose was to analyze their inclination to work at the primary and their selection preferences for economic incentive distribution methods under the current economic incentive policy. The data were analyzed by descriptive analysis, and the influencing factors of doctors′ willingness to work at the primary were analyzed by χ2 test and binary logistic regression. Results:A total of 254 valid questionnaires were collected with an effective recovery rate of 90.7%. Among the respondents, 189(74.4%) were willing to work at the primary, 168(66.1%) chose to receive the economic incentives specifically for working at the primary, and 148 people(58.3%) hoped to receive such economic incentives immediately. Education background, self-rated economic income level of doctors and different payment methods of economic incentive for working at the primary had significant effects on their willingness to work at the primary( P<0.05). Conclusions:The current economic incentive policy of the alliance can meet the demands for economic incentives in terms of doctors′ material accounts, and doctors′ overall inclination to work at the primary was strong. If the amount of economic incentives is constant, doctors preferred to receive the economic incentives specifically, mainly affected by income accounts and additional income accounts. In addition, education and self-assessment of economic income level were important factors affecting the willingness of doctors to work at the primary, which may be affected by mental accounts other than material accounts.