During long-term extravehicular activities(EVA),there have been multiple instances of localized discomfort due to cold extremities such as hands and feet.The primary reason is that the design of space suit gloves prioritizes maximizing operational flexibility,which leads to reduced passive thermal protection in certain areas.Insufficient local thermal protection can cause the hands to lose metabolic heat in cold environments over time,resulting in cold stress.Therefore,it is necessary to conduct research on temperature control technology to meet the thermal comfort requirements of astronauts' hands during EVA.Effective active temperature measures can expand the range of low temperature working environments that astronauts' hands can adapt to during EVA,enhance hand thermal comfort,and ensure hand operational capabilities,preventing excessive cold from exceeding medical requirement and affecting extravehicular missions.This paper combines the metabolic heat generation patterns of the human hand to analyze the temperature control requirements for extravehicular gloves,simulate and optimize the layout of electric heaters,and evaluate the feasibility of the electric heating system for extravehicular gloves by building a thermal simulation model.Through prototype vacuum thermal testing,comprehensive verification of the temperature control module for extravehicular gloves was achieved,demonstrating the effectiveness of the temperature control system.

Objective To develop a deep learning network based on attention mechanism to identify the number of the vertical man-dibular third molar(MTM)roots(single or double)on panoramic radiographs in an automatic way.Methods The sample consisted of 1 045 patients with 1 642 MTMs on paired panoramic radiographs and Cone-beam computed tomography(CBCT)and were randomly grouped into the training(80%),the validation(10%),and the test(10%).The evaluation of CBCT was defined as the ground truth.A deep learning network based on attention mechanism,which was named as RN-MTMnet,was trained to judge if the MTM on pano-ramic radiographs had one or two roots.Diagnostic performance was evaluated by accuracy,sensitivity,specificity,and positive predict value(PPV),and the receiver operating characteristic(ROC)curve with the area under the ROC curve(AUC).Its diagnostic perform-ance was compared with dentists'diagnosis,Faster-RCNN,CenterNet,and SSD using evaluation metrics.Results On CBCT images,single-rooted MTM was observed on 336(20.46%)sides,while two-rooted MTM was 1 306(79.54%).The RN-MTMnet achieved an accuracy of 0.888,a sensitivity of 0.885,a specificity of 0.903,a PPV of 0.976,and the AUC value of 0.90.Conclusion RN-MTM-net is developed as a novel,robust and accurate method for detecting the numberof MTM roots on panoramic radiographs.

Objective To design and produce a bleeding alert bandage and investigate its effectiveness in patients undergoing hemodialysis.Methods The bleeding alert bandage consists of elastic bandage,monitoring element and monitoring box.A convenience sampling method was used to select patients who received regular hemodialysis treatment in the blood purification center of a tertiary A comprehensive hospital in Anhui Province from January 2021 to June 2021.These patients were randomly assigned into an experimental group and a control group,with 40 cases in each group.Patients in the control group were inspected every 30 min by traditional method.Patients in the experimental group were monitored in real-time with a bleeding alert bandage in addition to the 30 min rounds.The detection rate,incidence,and volume of bleeding at the puncture site were compared in 2 groups of patients.Results The incidence of bleeding from the puncture sites was 17.00％in the experimental group and 25.25％in the control group,with statistical significance(x2=8.170,P=0.004).The incidence of bleeding for severe bleeding from puncture sites was 1.50％in the experimental group and 11.50％in the control group,with statistical significance(x2=32.910,P＜0.001).The bleeding detection rate from puncture sites was 94.12％in the experimental group and 89.11％in the control group,with no statistical difference(x2=1.261,P=0.262).The detection rate for moderate bleeding from puncture sites was 100％in the experimental group and 85.37％in the control group,with statistical significance(x2=6.170,P=0.013).Additionally,the bleeding volume from the puncture site was 1.29(0.88,1.74)g in the experimental group and 2.77(1.60,4.77)g in the control group,with statistical significance(Z=-5.825,P＜0.001).The moderate bleeding volume from the puncture site was 1.49(1.27,1.81)g in the experimental group and 1.92(1.52,2.44)g in the control group,with statistical significance(Z=-2.835,P=0.005).Conclusion The bleeding alert bandage is effective in real-time monitoring and alerting of bleeding at the puncture sites during hemodialysis,which can help reduce the incidence of blood seepage,improve the detection rate of blood seepage,reduce the amount of bleeding and improve the safety of dialysis treatment.

Objective To design and produce a bleeding alert bandage and investigate its effectiveness in patients undergoing hemodialysis.Methods The bleeding alert bandage consists of elastic bandage,monitoring element and monitoring box.A convenience sampling method was used to select patients who received regular hemodialysis treatment in the blood purification center of a tertiary A comprehensive hospital in Anhui Province from January 2021 to June 2021.These patients were randomly assigned into an experimental group and a control group,with 40 cases in each group.Patients in the control group were inspected every 30 min by traditional method.Patients in the experimental group were monitored in real-time with a bleeding alert bandage in addition to the 30 min rounds.The detection rate,incidence,and volume of bleeding at the puncture site were compared in 2 groups of patients.Results The incidence of bleeding from the puncture sites was 17.00％in the experimental group and 25.25％in the control group,with statistical significance(x2=8.170,P=0.004).The incidence of bleeding for severe bleeding from puncture sites was 1.50％in the experimental group and 11.50％in the control group,with statistical significance(x2=32.910,P＜0.001).The bleeding detection rate from puncture sites was 94.12％in the experimental group and 89.11％in the control group,with no statistical difference(x2=1.261,P=0.262).The detection rate for moderate bleeding from puncture sites was 100％in the experimental group and 85.37％in the control group,with statistical significance(x2=6.170,P=0.013).Additionally,the bleeding volume from the puncture site was 1.29(0.88,1.74)g in the experimental group and 2.77(1.60,4.77)g in the control group,with statistical significance(Z=-5.825,P＜0.001).The moderate bleeding volume from the puncture site was 1.49(1.27,1.81)g in the experimental group and 1.92(1.52,2.44)g in the control group,with statistical significance(Z=-2.835,P=0.005).Conclusion The bleeding alert bandage is effective in real-time monitoring and alerting of bleeding at the puncture sites during hemodialysis,which can help reduce the incidence of blood seepage,improve the detection rate of blood seepage,reduce the amount of bleeding and improve the safety of dialysis treatment.

Objective     To provide experience for clinical diagnosis and treatment through exploring the perioperative characteristics and short-term treatment outcomes of adult cardiac surgery in patients with prior coronavirus disease-2019 (COVID-19). Methods    A retrospective analysis was performed on patients undergoing coronary artery bypass grafting (CABG) or valve surgery in the Department of Cardiac Surgery of Beijing Anzhen Hospital from December 26, 2022 to December 31, 2022, and previously diagnosed with COVID-19 before surgery. Results    Finally 108 patients were collected, including 81 males and 27 females, with an average age of 60.73±8.66 years. Two (1.9%) patients received emergency surgery, and the others received elective surgery. The 86.1% of patients had been vaccinated, and the duration of COVID-19 was 5.0 (4.0, 7.0) days. The time from COVID-19 to operation was 15.0 (12.0, 17.8) days. Eighty-nine patients received CABG, of which off-pump CABG was dominant (92.1%). Nineteen patients received valve surgery. The rate of delayed extubation of ventilator was 17.6%. The ICU stay was 21.0 (17.3, 24.0) hours, and the postoperative hospital stay was 7.0 (6.0, 8.0) days. Three (2.8%) patients were treated with intra-aortic balloon  pump (IABP), one (0.9%) patient was treated with extracorporeal membrane oxygenation (ECMO), one (0.9%) patient was treated with continuous renal replacement therapy (CRRT) due to acute renal insufficiency, three (2.8%) patients were treated with temporary pacemaker, and one (0.9%) patient underwent rethoracotomy. In terms of postoperative complications, the incidence of cerebrovascular accident, acute renal insufficiency, gastrointestinal bleeding and septicemia was 0.9%, respectively, and the incidence of acute heart failure, lung infection, and liver insufficiency was 1.9%, respectively. All patients recovered and were discharged from hospital, and no in-hospital death occurred. Conclusion     The utilization rate of postoperative IABP, ECMO, CRRT, temporary pacemaker and the incidence of serious complications in patients with prior COVID-19 are not higher than those of normal patients, and the short-term treatment outcome is good.

Objective:This study was performed to assess the effect of glycemic control on atrial fibrillation recurrence rates after heart surgery concomitant with Cox-Maze Ⅳ ablation.Methods:A retrospective analysis was performed on 317 diabetic patients with atrial fibrillation who underwent cardiac surgery combined with Cox-Maze Ⅳ ablation in our hospital from May 2016 to February 2020. The patients were followed up for(37.7±27.7) months, and the data of atrial fibrillation recurrence and clinical outcome were collected and compared. The limited cubic spline model was used to analyze the dose-relationship between HbA1c level and the recurrence of atrial fibrillation. The univariate and multivariate Cox proportional regression analysis was used to explore the risk factors of recurrent atrial fibrillation after Cox-Maze Ⅳ ablation. Results:Higher glycated hemoglobin(HbA1c) at the time of ablation was associated with higher post-ablation recurrence rates. The cumulative survival freedom from atrial fibrillation recurrence for patients with HbA1c ≥7.4% at time of operation at 12, 24, 36 and 48 months were 96.3%、75.8%、52.7% and 35.7%, respectively( P<0.001). Besides, the rates of all-cause mortality, cardiac mortality and rehospitalization were significantly lower in patients with HbA1c<7.4%(1.7% vs. 6.3%, P=0.03; 1.1% vs. 5.6%, P=0.02 and 5.7% vs. 20.4%, P=0.01). The multivariate Cox regression model showed that HbA1c was an independent risk factor for atrial fibrillation recurrence( P<0.05). Conclusion:Higher preoperative HbA1c levels were associated with increased recurrence of atrial fibrillation and adverse clinical outcomes in patients undergoing cardiac surgery combined with Cox-Maze Ⅳ ablation.

Objective     To summarize the clinical characteristics and surgical treatment experience of 1 106 patients with cardiac myxoma. Methods     Clinical data of 1 106 patients with cardiac myxoma who underwent surgical treatment in Beijing Anzhen Hospital from 2002 to 2018 were retrospectively analyzed. There were 749 (67.7%) females and 357 (32.3%) males. Results     The highest incidence rate was at the age of 51-70 years. The location of the disease was: left atrium in 987 (89.2%) patients, right atrium in 99 (9.0%) patients, left ventricle in 10 (0.9%) patients, right ventricle in 8 (0.7%) patients. There were 1 013 patients of heart classification (NYHA) Ⅰ-Ⅱ and 93 patients of Ⅲ-Ⅳ. There were 301 patients with cerebral infarction and 57 patients with peripheral arterial embolism. Tumor size was closely related to hemodynamic symptoms (P≤0.05), but not to peripheral vascular embolism (P>0.05). Two (0.2%) patients died in hospital and 306 patients were followed up, with a follow-up rate of 27.7%. The median follow-up time was 7 years (range, 1-18 years). One patient died of all causes, and 23 patients recurred, with a recurrence rate of 2.1%. Among 23 recurrent patients, 15 (65.2%) patients were atypical myxoma and 8 (34.8%) patients were typical myxoma. There was no statistical difference in aortic clamping time, ICU stay time, ventilator-assisted breathing time, postoperative hospital stay time, postoperative mortality, or cardiac ejection fraction at discharge between the reoperation in 23 recurrent patients and the first operation in 1 083 non-recurrentpatients. Conclusion     Cardiac myxoma is more common in middle-aged and elderly women, and it often occurs in the left atrium. The size of cardiac myxoma can affect the hemodynamic changes. Surgical treatment is effective. Atypical myxoma is more common in recurrent patients, and the effect is still satisfactory through surgical treatment.

Objective:To analyze the composition, the changes of expense structure and the influencing factors of hospitalization expenses, for reference in optimizing the cost control of day surgery.Methods:Collection of the first page data of patients with the top three diseases(varicose veins of lower limbs, chronic cholecystitis and varicocele)in the day surgery volume ranking in three tertiary general hospitals in a city in 2020. The confounding factors were eliminated through propensity matching. The structural change of hospitalization expenses was analyzed by structural change degree, and the influencing factors of hospitalization expenses were analyzed by grey correlation degree and multiple linear regression.Results:After 1∶1 propensity matching of the first page data of 752 patients with day surgery and non day surgery, 98 patients with lower extremity varicose veins, 356 patients with chronic cholecystitis and 38 patients with varicocele were finally included. Compared with non day hand, the total hospitalization cost of day surgical instruments decreased, and the cost structure changes of chronic cholecystitis, varicocele and varicose veins of lower limbs were 14.59%, 6.20% and 16.20% respectively. Among them, the general medical service fee, nursing fee and examination and laboratory fee showed a downward trend, and the fees of materials and drugs showed an upward trend. General medical service fee, nursing fee, examination and laboratory fee, clinical diagnosis fee, treatment fee, drug fee, material fee and other expenses presented a high correlation with the cost of day surgery(grey correlation>0.90). The payment method, wound healing type and discharge diagnosis can influence the cost of day surgery( P<0.05). Conclusions:Compared with non daytime surgery, the total hospitalization cost of day surgery has a certain cost control effect, but it can not reduce the cost of all projects. The main influencing factors are the internal composition of the cost, payment method and so on. The hospitals should focus on tapping the internal cost control potential of day surgery and further expanding the coverage of day surgery diseases.

Objective:To summarize the experience of reoperation for 23 cases of cardiac myxoma recurrence.Methods:From January 2002 to December 2018, 1106 patients with cardiac myxoma underwent surgical treatment. Among them, 23 patients underwent reoperation after recurrence. 10 males and 13 females with an average age of (50.5±10.8) years old. There were 22 patients with secondary operation and 1 patient with four operations. 3 cases with mitral insufficiency and 1 case with tricuspid insufficiency. There were 20 patients with NYHA Ⅰ-Ⅱ and 3 patients with Ⅲ-Ⅳ. A total of 1 083 patients with cardiac myxoma undergoing primary operation were selected as the control group. The operation time, cardiopulmonary bypass time, aortic clamping time, ICU monitoring time, ventilator assisted breathing time, postoperative hospital stay, in-hospital mortality and cardiac ejection fraction at discharge were compared between the two groups.Results:8 cases (34.8%) had the first onset in the left atrial septum, and 15 cases (65.2%) in other parts. Recurrence site: left atrium in 17 cases(73.9%), left ventricle in 2 cases (8.7%), right atrium in 3 cases (13.0%), right ventricle in 1 case (4.3%). Reoperation accounted for 2.1% of cardiac myxoma surgery in the same period. The median recurrence time of 13 patients was 24 months. During the same period, mitral valve replacement was performed in 2 cases, mitral valvuloplasty in 1 case and tricuspid valve plasty in 1 case. The average operation time was (3.9±2.8) h, cardiopulmonary bypass time was (107.6±33.8) min, aortic clamping time was (64.9±23.8) min, ICU monitoring time was (20.1±16.0) h, ventilator assisted breathing time was (16.9±8.5) h, cardiac ejection fraction at discharge was 0.51±0.10, postoperative hospital stay was (8.3±1.5) days. The median follow-up time was 5 (1-18) years. One case (4.3%) died of all causes. There was no significant difference in ICU monitoring time, ventilator assisted breathing time, discharge cardiac ejection fraction, postoperative hospital stay and hospital mortality between reoperation patients and one operation ( P>0.05). Conclusion:Atypical cardiac myxoma has a high recurrence tendency after operation. Regular follow-up after the first operation of cardiac myxoma is a necessary means to early detect recurrence and avoid complications. Reoperation after recurrence can still achieve satisfactory results.

The treatment of heart failure is a common clinical problem faced by the medical community all over the world. It is also the only cardiovascular disease in the world that is on the rise. Although drug therapy for heart failure has made great progress in recent years, there are still many problems. Therefore, reversing ventricular remodeling, assisting or even replacing the function of the damaged heart and improving the prognosis and quality of life of patients with heart failure through surgical treatment will become the main battlefield for the future treatment of heart failure. As a transitional support therapy or permanent replacement therapy before heart transplantation, ventricular assist device can significantly improve the survival and quality of life of patients with heart failure, and is becoming an important treatment method for patients with end-stage heart failure. This paper aim to review the history and prospect of ventricular assist devices after heart failure.