BACKGROUND:Post and core restoration is a common choice for tooth defects,but the repair effects of various post and core materials are different. OBJECTIVE:To evaluate the stress distribution at the post and core,tooth root,and bonding agent site of post and core models made of different elastic modulus post and core materials using finite element method. METHODS:A three-dimensional root canal treated maxillary central incisor model was built using three-dimensional modeling software,which was restored with a full ceramic crown.The post and core materials in the restoration used nanoceramic resin(elastic modulus=12.8 GPa),composite resin(elastic modulus=16 GPa),hybrid ceramic(elastic modulus=34.7 GPa),glass ceramic(elastic modulus=95 GPa),titanium alloy(elastic modulus=112 GPa),and zirconia(elastic modulus=209.3 GPa).The model was fixed in cortical bone.A 100 N concentrated force of 45° from the long axis of the tooth was applied to 1/3 of the crown and tongue side of the central incisor.The stress distribution of the post and core,dentin,and tooth-root bonding agent in the model was repaired by the maximum principal stress criterion. RESULTS AND CONCLUSION:(1)When the post and core materials with higher elastic modulus was used,the post-core stress in the repair model was more concentrated.When the elastic modulus of the post and core materials(nanoceramic resin and composite resin)was close to dentin,the stress distribution of the post and core was more uniform.The stress distribution of dentin in all restoration models was similar regardless of post and core materials.When the post and core with higher elastic modulus was used,more stress concentration was shown at the post and root bonding agent in the repair model.(2)The maximum stress values at the post and core,tooth root,and the bonding agent site of post and tooth root in the nanoceramic resin model were 31.00,33.21,and 0.51 MPa,respectively.The maximum stress values at the post and core,tooth root,and the bonding agent between the post and tooth root in the composite resin model were 36.84,33.14,and 0.59 MPa,respectively.In the mixed ceramic model,the maximum stress values at the post and core,tooth root,and the bonding agent between the post and tooth root were 64.05,32.83,and 1.00 MPa,respectively.In the glass ceramic model,the maximum stress values at the post and core,tooth root,and the bonding agent between the post and tooth root were 112.30,32.69,and 1.73 MPa,respectively.In the titanium alloy model,the maximum stress values of the post and core,tooth root,and the bonding agent between the post and tooth root were 120.00,32.17,and 1.86 MPa,respectively.In the zirconia model,the maximum stress values of the post and core,tooth root,and the bonding agent between the post and tooth root were 148.80,31.85,and 2.28 MPa,respectively.(3)The higher the elastic modulus of the post and core material,the higher the maximum stress at the post and core during restoration.The elastic modulus of the post and core material had no significant effect on the maximum stress of the dental bonding agent and dentin.

Objective: To analyze the impact of parental sports concept and behavior on physical activity in preschool children, so as to provide a foundation for future guidance on fostering childrens physical activity within the family context. Methods: From November to December 2020, a clustered convenience sampling method was employed to conduct surveys, and a total of 283 children were selectal from one kindergarten each in Beijing, Shenyang, and Xian. Participating children wore ActiGraph GT9X accelerometers continuously for one week to collect data on different intensity levels of physical activity. Physical Activity afterschool Questionnaire for Preschooler (P-PAQ) was utilized to assess parental sports concept and behavior. The gender differences in physical activity level and physical activity compliance rate were analyzed by using ttest, Mann-Whitney U test, and Chisquare test; and the relationship between parental exercise concepts and behaviors and physical activity of preschool children was analyzed using Spearman rank correlation analysis and multiple linear regression analysis. Results: Parental sports concept was significantly positively correlated with average daily moderatetovigorous physical activity (MVPA) and total physical activity (TPA) in children (r=0.12-0.16, P<0.05). Parental sports behavior was significantly positively correlated with childrens average daily TPA (r=0.25, P<0.05). Multiple linear regression revealed that parental sports concept was positively correlated with average daily MVPA and TPA in both boys and girls (B=0.65-0.83), while parental sports behavior only was positively correlated with boys average daily MVPA and TPA (B=0.24-0.25)(P<0.05). Conclusions Parental sports concept and behavior can impact physical activity levels in preschool children, exhibiting gender differences. Future guidance on physical activity in family upbringing should consider both parental sports concept and behavior, and pay attention to the influence of childrens gender.

Objective To acquire,evaluate and integrate the best evidence of perioperative exercise interventions in patients with liver cancer and provide evidence-based references for clinical medical staff.Methods Following the"6S"Evidence Resource Pyramid model,literatures in perioperative exercise interventions published between January 2010 and June 2022 were retrieved from various databases,including BMJ Best Practice,UpToDate,Guidelines International Network,National Guideline Clearinghouse,National Institute for Health and Clinical Excellence,Scottish Intercollegiate Guidelines Network,Medlive,Cochrane Library,JBI,Web of Science,PubMed,Embase,CINAHL,CNKI,SinoMed,Wanfang Data,American Cancer Society,American College of Sports Medicine and International Liver Cancer Association from January 2010 to June 2022.Two researchers evaluated the quality of the retrieved literatures and extracted evidences that met the inclusion criteria.Results A total of 22 articles were included,yielding 26 pieces of evidence across seven themes:the necessity of exercise,evaluation before exercise,preoperative exercise program,postoperative exercise program,exercise monitoring,health education and effect evaluation.Conclusions This study provides a summary of the best evidence regarding perioperative exercise interventions in the patients with liver cancer.The findings offer valuable references for clinical healthcare providers to deliver evidence-based care for the patients with liver cancer.

Objective:To evaluate the association between preoperative serum β 2-microglobulin (β 2MG) concentrations and postoperative delirium (POD) in elderly patients. Methods:The study selected patients who underwent knee or hip arthroplasty under spinal-epidural anesthesia on an elective basis at Qingdao Municipal Hospital from May 2021 to November 2022. The patients were divided into a POD group and a non-POD group based on the occurrence of POD. The study was conducted as part of the Perioperative Neurocognitive Impairment and Biomarkers Lifestyle Cohort, which was a nested case-control study. The study collected baseline data from two groups of patients and analyzed the differences between them. Logistic regression was used to identify the risk factors for POD. The stability of the regression model was tested using sensitivity analysis. The mediation model was used to examine whether cerebrospinal fluid (CSF) biomarkers mediated the relationship between β 2MG and POD. The receiver operating characteristic curve was drawn and the area under the curve was calculated to evaluate the accuracy of preoperative β 2MG concentrations and CSF biomarker concentration in predicting POD. Results:There were 57 cases in POD group and 449 cases in non-POD group. The results of logistic regression analysis showed that the increased β 2MG and CSF total tau protein (t-tau) concentrations were risk factors for POD, and the increased CSF β-amyloid 42 concentration was a protective factor for POD after adjustment for multiple confounders such as age, gender, education, Mini-Mental State Examination, history of hypertension and infusion volume ( P<0.05). The results of mediation analysis showed that the serum β 2MG′s effect on POD was partly mediated by t-tau (18.1%). The results of the receiver operating characteristic curve showed that the area under the curve of the β 2MG concentration combined with the CSF biomarker concentration was 0.742. Conclusions:Elevated preoperative serum β 2MG concentration is a risk factor for POD in elderly patients, and the relationship may be partly mediated by CSF t-tau.

Objective:To evaluate the relationship between preoperative serum bilirubin concentrations and postoperative delirium (POD) in the patients undergoing knee or hip replacement.Methods:Medical records from 413 patients undergoing knee or hip arthroplasty were selected from August 2020 to October 2023 at Qingdao Municipal Hospital using a nested case-control design based on the PNDABLE study cohort. The patients were divided into POD group ( n=77) and non-POD group ( n=336) according to whether POD occurred. Univariate analysis was used to analyze the influencing factors. Logistic regression was used to identify the risk factors for POD. The significance of mediation effect was tested. The receiver operating characteristic curve was drawn to evaluate the accuracy of risk factors in predicting POD. Results:There were significant differences in age, education time, ratio of diabetes history, Memorial Delirium Assessment Scale score, total bilirubin concentration, direct bilirubin concentration, indirect bilirubin concentration, Aβ 42 concentration, p-tau concentration, t-tau concentration, Aβ 42/p-tau ratio and Aβ 42/t-tau ratio between POD group and non-POD group ( P<0.05). The results of logistic regression analysis showed that preoperative serum total bilirubin, direct bilirubin and indirect bilirubin were risk factors for POD ( P<0.05). The results of mediation effects showed that the concentration of total tau protein in CSF partly mediated the relationship between high serum total bilirubin, direct bilirubin and indirect bilirubin concentrations and POD. The area under the receiver operating characteristic curve of total bilirubin, direct bilirubin and indirect bilirubin combined with CSF biomarker concentrations in predicting POD was 0.83 ( P<0.001). Conclusions:Preoperative elevated concentrations of total bilirubin, direct bilirubin and indirect bilirubin are risk factors for POD in the patients undergoing knee or hip replacement. CSF t-tau concentration has a partly mediating role in the association between serum total bilirubin, direct bilirubin and indirect bilirubin concentrations and the development of POD.

Background and objective Invasive mucinous adenocarcinoma(IMA)was a rare and specific type of lung adenocarcinoma,which was often characterized by fewer lymphatic metastases.Therefore,it was difficult to evaluate the prognosis of these tumors based on the existing tumor-node-metastasis(TNM)staging.So,this study aimed to develop Nomo-grams to predict outcomes of patients with pathologic N0 in resected IMA.Methods According to the inclusion criteria and exclusion criteria,IMA patients with pathologic N0 in The Affiliated Lihuili Hospital of Ningbo University(training cohort,n=78)and Ningbo No.2 Hospital(validation cohort,n=66)were reviewed between July 2012 and May 2017.The prognostic value of the clinicopathological features in the training cohort was analyzed and prognostic prediction models were established,and the performances of models were evaluated.Finally,the validation cohort data was put in for external validation.Results Univariate analysis showed that pneumonic type,larger tumor size,mixed mucinous/non-mucinous component,and higher overall stage were significant influence factors of 5-year progression-free survival(PFS)and overall survival(OS).Multivariate analysis further indicated that type of imaging,tumor size,mucinous component were the independent prognostic factors for poor 5-year PFS and OS.Moreover,the 5-year PFS and OS rates were 62.82％and 75.64％,respectively.In subgroups,the sur-vival analysis also showed that the pneumonic type and mixed mucinous/non-mucinous patients had significantly poorer 5-year PFS and OS compared with solitary type and pure mucinous patients,respectively.The C-index of Nomograms with 5-year PFS and OS were 0.815(95％CI:0.741-0.889)and 0.767(95％CI:0.669-0.865).The calibration curve and decision curve analysis(DCA)of both models showed good predictive performances in both cohorts.Conclusion The Nomograms based on clinicopathological characteristics in a certain extent,can be used as an effective prognostic tool for patients with pathologic N0 after IMA resection.

Objective:To explore the application effects of case nursing review based on training transfer theory in specialized nurses training, and to provide reference for promoting the knowledge and skills transformation of specialized nurses.Methods:A total of 64 specialized nurses from Longgang District Maternity & Child Healthcare Hospital of Shenzhen City were selected as subjects by convenient sampling from June 10 to July 20, 2022 and divided into control group and observation group by random number table method. The control group received routine core competence training, while the observation group received case nursing review based on training transfer theory. The training duration of both groups was 12 months. Within 1 month after the training, the training satisfaction, nursing case report quality score, core competence of specialized nurses, patient satisfaction and training transfer outcomes of the two groups were compared.Results:Finally, 62 specialist nurses were included, with 31 nurses in control group and observation group, 2 males and 29 females in each group, aged (34.10 ± 3.93) years in control group and (33.35 ± 3.06) years in observation group. Before training, there were no significant differences in nursing case report quality score, total score of core competence of specialized nurses and patient satisfaction between the two groups (all P> 0.05). After training, the nursing case quality score, total score of core competence and patient satisfaction in the observation group were 73.00(68.00, 78.00), 179.00(175.00, 183.00), 96.00(94.00, 99.00) points, which were higher than 85.00(80.00, 89.00), 163.00(162.00, 166.00), 88.00(85.00, 92.00) points in the control group, and the differences were statistically significant ( Z = 5.81, 6.73, 13.31, all P<0.05). The total training satisfaction of nurses, awards in professional competitions and the number of technological innovations in the observation group were 21.00(20.00, 22.00) points, 15 awards, 8 innovations, which were higher than 15.00(14.00, 16.00) points, 5 awards, 2 innovations in the control group, and the differences were statistically significant ( Z = 6.74, χ2 = 7.38, 4.29, all P<0.05). Conclusions:The application of case nursing review based on training transfer theory can improve the training satisfaction of specialist nurses, stimulate their motivation to transfer training, and improve their ability and effectiveness in training transfer.

Aim To explore the feasibility of using machine learning algorithms combined with coronary computed tomography(CT)derived perivascular fat attenuation index(FAI)and plaque information to evaluate myocardial ischemia in stable coronary heart disease patients.Methods A retrospective analysis was conducted on the clinical and imaging data of patients who underwent preoperative coronary CT angiography(CCTA),invasive coronary angiography(ICA),and flow reserve fraction(FFR)measurements at Zhongshan Hospital Affiliated to Fudan University from April 2019 to October 2021.206 patients with stable coronary heart disease were selected.The semi-automatic plaque analysis software was used for quantification of plaque and lumen parameters and perivascular FAI measurement,with man-ual delineation of a 40 mm segment of the coronary artery starting 10 mm from the ostium for perivascular FAI measure-ment.Differences in plaque characteristics,perivascular FAI,and coronary perivascular FAI between stable coronary heart disease patients with FFR≤0.8 and FFR＞0.8 were compared.The diagnostic performance of combining perivascu-lar FAI,coronary perivascular FAI,and plaque features using machine learning algorithms for myocardial ischemia in stable coronary heart disease patients was evaluated through ROC curves.Results 206 stable coronary heart disease patients were divided into FFR≤0.8 group(50 cases)and FFR＞0.8 group(156 cases).The mean periplaque FAI of patients with FFR≤0.8 was-69.28±5.65 HU,significantly higher than that of patients with FFR＞0.8 at-80.10±7.75 HU(P＜0.001).Further analysis was conducted using machine learning models,including XGBoost,random forest,and Logistic regression models,all of which had an accuracy rate of over 0.8 in diagnosing myocardial ischemia.Among them,the XGBoost model performed the best with an accuracy of 0.903,an F1 value of 0.774,and an AUC of 0.931,in-dicating its high effectiveness in diagnosing myocardial ischemia.Conclusion The combination of FAI and machine learning algorithm XGBoost model is a new method for diagnosing myocardial ischemia,which has better diagnostic value in evaluating myocardial ischemia in stable coronary heart disease patients.

Objective To understand the changing distribution and antimicrobial resistance profiles of Proteus,Morganella and Providencia in hospitals across China from January 1,2015 to December 31,2021 in the CHINET Antimicrobial Resistance Surveillance Program.Methods Antimicrobial susceptibility testing was carried out following the unified CHINET protocol.The results were interpreted in accordance with the breakpoints in the 2021 Clinical & Laboratory Standards Institute(CLSI)M100(31 st Edition).Results A total of 32 433 Enterobacterales strains were isolated during the 7-year period,including 24 160 strains of Proteus,6 704 strains of Morganella,and 1 569 strains of Providencia.The overall number of these Enterobacterales isolates increased significantly over the 7-year period.The top 3 specimen source of these strains were urine,lower respiratory tract specimens,and wound secretions.Proteus,Morganella,and Providencia isolates showed lower resistance rates to amikacin,meropenem,cefoxitin,cefepime,cefoperazone-sulbactam,and piperacillin-tazobactam.For most of the antibiotics tested,less than 10％of the Proteus and Morganella strains were resistant,while less than 20％of the Providencia strains were resistant.The prevalence of carbapenem-resistant Enterobacterales(CRE)was 1.4％in Proteus isolates,1.9％in Morganella isolates,and 15.6％in Providencia isolates.Conclusions The overall number of clinical isolates of Proteus,Morganella and Providencia increased significantly in the 7-year period from 2015 to 2021.The prevalence of CRE strains also increased.More attention should be paid to antimicrobial resistance surveillance and rational antibiotic use so as to prevent the emergence and increase of antimicrobial resistance.

Objective:To explore the mediating effect of distress disclosure between perceived social support and psychological distress in colorectal cancer patients.Methods:The convenient sampling method was used to select 220 postoperative colorectal cancer patients who were reviewed in China-Japan Union Hospital of Jilin University from February to August 2023 as the research objetcs. The Distress Disclosure Index (DDI), Perceived Social Support Scale (PSSS), and Chinese version of Screening Tool for Psychological Distress in Cancer Patients were used to conduct the survey.Results:A total of 220 questionnaires were distributed in this study, and 213 valid questionnaires were recovered, with a valid recovery rate of 96.82%. The total score of the Chinese version of Screening Tool for Psychological Distress in Cancer Patients for colorectal cancer patients was (4.31±2.46), the total score of the DDI was (37.26±9.97), and the total score of the PSSS was (57.82±14.60). Pearson correlation analysis showed that psychological distress was negatively correlated with distress disclosure in colorectal patients ( P<0.01), distress disclosure was positively correlated with perceived social support ( P<0.01), and psychological distress was negatively correlated with perceived social support ( P<0.01). The mediating effect results showed that the direct effect of perceived social support on psychological distress was -0.359 ( P<0.01), and the mediating effect between perceived social support and psychological distress was -0.227 ( P<0.01), which acted as a partial mediating effect with the mediating effect accounting for 38.74% of the total effect. Conclusions:Perceived social support can not only directly affect the psychological distress of colorectal cancer patients, but also indirectly affect psychological distress through distress disclosure. Clinical staffs should take certain interventions to improve the level of patients' perceived social support and distress disclosure, so as to improve the psychological distress of patients.