Objective:To understand the major cognition, major choice motivation and the relationship between the two of medical students, and provide references and suggestions for the selection of talents in various majors of medical schools and the effective development of enrollment work.Methods:This study selected undergraduates of Batch 2019 from Peking University Health Science Center as the survey objects, conducted a questionnaire survey on their major cognition, major choice motivation and influencing factors, and used principal component analysis and Spearman rank correlation analysis.Results:The study found that the major cognition scores of 640 undergraduates of Batch 2019 from Peking University Health Science Center were clinical medicine (3.24±0.89) > stomatology (2.89±1.00) > basic medicine (2.66±1.02) > pharmacy (2.54±0.97) > preventive medicine (2.29±0.93) > nursing medicine (2.21±0.99) > medical laboratory (1.98±0.95) > medical English (1.95±0.93). Six major motivation factors for professional choice were school and professional strength, professional learning and job prospects, own factors, Peking University sentiments and the influence of others, medical factors, school policies, and the contribution rates were 34.60%, 12.97%, 7.42%, 6.00%, 5.59% and 5.37%, respectively. Major cognition scores and major choice motivation factors were positively correlated with each other to some extent.Conclusions:At present, students' major cognition level of medical majors still has a large room for improvement, and the motivational factors of major choice are more complicated, among which "the school and professional strength" and "the prospects of study and work" are important factors. Medical schools should focus on strengthening major publicity, improving students' major cognition, attracting aspiring students to apply for medical majors from many aspects, and improving the training quality of medical professionals.

Objective:To explore the effects of short-term particulate matter(PM)exposure and the melatonin receptor 1B(MTNR1B)gene on triglyceride-glucose(TyG)index utilizing data from Fang-shan Family-based Ischemic Stroke Study in China(FISSIC).Methods:Probands and their relatives from 9 rural areas in Fangshan District,Beijing,were included in the study.PM data were obtained from fixed monitoring stations of the National Air Pollution Monitoring System.TyG index was calculated by fasting triglyceride and glucose concentrations.The associations of short-term PM exposure and rs10830963 polymorphism of the MTNR1B gene with the TyG index were assessed using mixed linear models,in which covariates such as age,sex,and lifestyles were adjusted for.Gene-environment inter-action analysis was furtherly performed using the maximum likelihood methods to explore the potential effect modifier role of rs10830963 polymorphism in the association of PM with TyG index.Results:A total of 4 395 participants from 2 084 families were included in the study,and the mean age of the study participants was(58.98±8.68)years,with 53.90％females.The results of association analyses showed that for every 10 μg/m3 increase in PM2.5 concentration,TyG index increased by 0.017(95％CI:0.007-0.027),while for per 10 μg/m3 increment in PM1o,TyG index increased by 0.010(95％CI:0.003-0.017).And the associations all had lagged effects.In addition,there was a positive association between the rs10830963 polymorphism and the TyG index.For per increase in risk allele G,TyG index was elevated by 0.040(95％CI:0.004-0.076).The TyG index was 0.079(95％CI:0.005-0.152)higher in carriers of the GG genotype compared with carriers of the CC genotype.The inter-action of rs10830963 polymorphism with PM exposure had not been found to be statistically significant in the present study.Conclusion:Short-term exposure to PM2.5 and PM10 were associated with higher TyG index.The G allele of rs10830963 polymorphism in the MTNR1B gene was associated with the elevated TyG index.

Objective:To explore the association between polymorphisms of transforming growth factor-β(TGF-β)signaling pathway and non-syndromic cleft lip with or without cleft palate(NSCL/P)among Asian populations,while considering gene-gene interaction and gene-environment interaction.Methods:A total of 1 038 Asian NSCL/P case-parent trios were ascertained from an international consortium,which conducted a genome-wide association study using a case-parent trio design to investigate the genes affec-ting risk to NSCL/P.After stringent quality control measures,343 single nucleotide polymorphism(SNP)spanning across 10 pivotal genes in the TGF-β signaling pathway were selected from the original genome-wide association study(GWAS)dataset for further analysis.The transmission disequilibrium test(TDT)was used to test for SNP effects.The conditional Logistic regression models were used to test for gene-gene interaction and gene-environment interaction.Environmental factors collected for the study in-cluded smoking during pregnancy,passive smoking during pregnancy,alcohol intake during pregnancy,and vitamin use during pregnancy.Due to the low rates of exposure to smoking during pregnancy and al-cohol consumption during pregnancy(＜3％),only the interaction between maternal smoking during pregnancy and multivitamin supplementation during pregnancy was analyzed.The threshold for statistical significance was rigorously set at P=1.46 × 10-4,applying Bonferroni correction to account for multiple testing.Results:A total of 23 SNPs in 4 genes yielded nominal association with NSCL/P(P＜0.05),but none of these associations was statistically significant after Bonferroni's multiple test correction.How-ever,there were 6 pairs of SNPs rs4939874(SMAD2)and rs1864615(TGFBR2),rs2796813(TGFB2)and rs2132298(TGFBR2),rs4147358(SMAD3)and rs1346907(TGFBR2),rs4939874(SMAD2)and rs1019855(TGFBR2),rs4939874(SMAD2)and rs12490466(TGFBR2),rs2009112(TGFB2)and rs4075748(TGFBR2)showed statistically significant SNP-SNP interaction(P＜1.46 × 10-4).In contrast,the analysis of gene-environment interactions did not yield any significant results after being cor-rected by multiple testing.Conclusion:The comprehensive evaluation of SNP associations and interac-tions within the TGF-β signaling pathway did not yield any direct associations with NSCL/P risk in Asian populations.However,the significant gene-gene interactions identified suggest that the genetic architec-ture influencing NSCL/P risk may involve interactions between genes within the TGF-β signaling path-way.These findings underscore the necessity for further investigations to unravel these results and further explore the underlying biological mechanisms.