To investigate the aging behavior of fluoroelastomer FM-1D in hot air,with compression set as a parameter for seal aging,aging tests were conducted on fluoroelastomer FM-1D under different initial compression rates in a hot air environment ranging from 60℃to 150℃.The aging kinetic equation relating compression set of FM-1D to temperature and time was established,in order to predict its aging life at 25℃.The test results indicated that when the initial compression rate was 30%,the compression set exhibited an Arrhenius relationship with both test temperature and time.However,at a initial compression rate of 50%,the compression set gradually conformed to the Arrhenius relationship as time extended.These findings provide a reference for determining accelerated testing methods and maintenance cycles for FM-1D rubber materials.

Gathering together is an effectual way for improving quality and efficiency of the physical and chemical regenerative environmental control and life support system,as a regenerative gathering together technology,solid amine can simultaneously gather carbon dioxide and humidity with mild adsorption and desorption conditions,thus having the potential for miniaturization and low energy consumption,making it very suitable for manned deep space exploration missions.The current domestic and foreign systems cannot achieve perfect heat exchange between adsorption and desorption,resulting in low efficiency and less obvious comprehensive advantages.This study utilized multi-physics simulation methods to optimize system heat transfer,designed a combined control system for carbon dioxide and humidity,and verified various system characteristics such as flow rate and cycle time.The results show that:The designed porous thermal conductive medium can effectively reduce thermal resistance,and the obtained optimal filling ratio and structural size improve the heat transfer efficiency of the system.By adjusting the system characteristics,it is possible to dynamically satisfy the carbon dioxide and humidity control needs for 1～3 crews at different metabolic levels.This study verified the advantages of the regenerative combined carbon dioxide and humidity gathering system in terms of weight,power consumption,and volume,and obtained system characteristics,providing important technical support for manned deep space exploration missions.

To evaluate the aging life of silicone rubber sealing materials in the electrolytic water environment,the compression permanent distortion was taken as the performance change parameter of the sealing ring.Three typical silicone rubber materials,G146,G199,and 6144,were subjected to aging tests in the electrolytic water.The aging data was analyzed by the Arrhenius equation.And the aging kinetics equation of permanent compression deformation retention rate and temperature time was established,the aging life of silicone rubber sealing materials at 25℃was predicted.The results indicate the aging life of G146,G199,and 6144,was 21.3 a,9.8 a,and 12.0 a respectively.These prediction results provide a reference for determining the maintenance cycle of the sealing material.

Objective:To investigate the efficacy of emergency endoscopic hemostasis for the treatment of delayed bleeding after endoscopic sphincterotomy(EST).Methods:Clinical data of 5 patients with delayed bleeding after EST,who received emergen-cy endoscopic hemostasis during Jan 2013 and Dec 2014,were analyzed retrospectively,so as to evaluate the efficacy of emer-gency endoscopic hemostasis.Results:Delayed bleeding occurred within 24 h in 3 patients,3 d after EST in 1 patient,and 7 d after EST in 1 patient.Once the hemorrhagic lesion had been found by endoscopy,electrocoagulation,epinephrine injection, sclerosing agent injection,or hemoclipping was applied to hemostasis.Endoscopic hemostasis was successfully achieved in all pa-tients.No recurrent bleeding was observed during the follow-up.Conclusions:Emergency endoscopic hemostasis is simple to operate,safe and effective for the treatment of delayed bleeding after EST.

Objective To analyze the clinical and histological features of drug-induced autoimmune hepatitis (DI-AIH).Methods From January 2008 to June 2011,five patients with auto-immune hepatitis (AIH),having a definitive history of medicine taking prior to the onset of disease and accepted liver biopsy were retrospectively analyzed.The general information was collected,which included gender,age,onset of the disease,medication,clinical manifestations,treatment and follow-up.The laboratory findings were also collected,which included total bilirubin (TBil),direct bilirubin (DBil),alanine transaminase (ALT),aspartate transaminase (AST),alkaline phosphatase (ALP),gamma glutamyl transpeptidase (GGT),globulin,γ-globulin percentage,albumin (Alb),eosinophils,antinuclear antibodies,antimitochondrial antibodies,anti-smooth muscle antibodies and the type of live injury.The liver tissue sections of patients were stained with hematoxylin-eosinstaining (HE) and reticular fiber staining and then pathological changes were observed.Patients with DI-AIH were scored with AIH scoring scale.Results All five patients with DI-AIH were female,average age was 48.0--+7.5.Prior to the onset of disease,all patients had taken Chinese traditional medicine.Anorexia and fatigue were the most common clinical symptoms.Among laboratory findings,the level of ALT ((795.0+467.4) U/L),AST ((730.44-451.5) U/L),TBil ((80.3-+ 64.1) μmol/L) and DBil ((65.2 +_ 58.0) μmol/L) significantly increased.One patient was antinuclear antibody positive.One patient had drug-induced liver injury,pathological features were spotty necrosis of liver cells,liver tissue eosinophil infiltration and liver cell microbubble type degeneration.All the patients had interface hepatitis,periportal infiltration of lymphocytes or lymphocytes-plasma cells,liver cells adjacent to lesion showed rosette-like structure.All the patients received glucocorticoid treatment.After glucocorticoid withdrawal,the liver function was normal during the follow-up period.Conclusion There are no specificity of clinical manifestations,laboratory findings and histological features in patients with DI-AIH.

Objective To investigate the effects of permissive hypercapnia ventilation on cerebral oxygen metabolism and postoperative cognitive function in elderly patients.Methods One hundred and twenty ASA Ⅰ-Ⅲ patients,aged 65-80 yr,undergoing elective lower abdominal surgery under general anesthesia,were randomly divided into 2 groups (n=60 each): routine ventilation group (group R) and permissive hypercapnia ventilation group (group H).In group H,VT=6-8 ml/kg,RR=12-14 bpm,I: E=1: 2,and PaCO2 was maintained at 45-65 mm Hg and pH value ＞ 7.2,while in group R,VT=10-12 ml/kg,RR=14-16 bpm,I:E=1:2,and PaCO2 was maintained at 35-45 mm Hg.Blood samples were taken from the radial artery and jugular bulb for blood gas analyses at 0,5,15 and 30 min after tracheal intubation (T0.3).Cerebral A-V O2 content differences (Da-jvO2)and cerebral O2 extraction rate (CERO2) were calculated at the same time.Cognitive function was assessed by Mini-Mental State Examination (MMSE) at 1 day before operation,and 24 h,48 h,1 week and 2 weeks after operation.Results Compared with group R,PEr CO2 andPaCO2 were significantly increased,and pH value,Da-jvO2 and CERO2 were significantly decreased at T1.3,MMSE score was significantly increased after operation,and the incidence of post-operative cognitive dysfunction was significantly decreased after operation (P ＜ 0.05 or0.01).Compared with the baseline value at T0,Da-jvO2 and CERO2 were significantly decreased at T1-3 in both groups,PETCO2 and PaCO2 were significantly increased,and pH value,Da-jvO2 and CERO2 were significantly decreased at T1-3 in group H,and MMSE score was significantly decreased at 24 h,48 h,1 week and 2 weeks after operation in both groups (P ＜ 0.01).Conclusion Permissive hypercapnia ventilation can improve the cerebral oxygen metabolism during operation,and reduce post-operative cognitive dysfunction in the elderly patients.