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To solve the problems of low computational efficiency and missing amplitude information existing in the current multiscale sample entropy（MSE） method when extracting features of complex series, refined improved multiscale fast sample entropy（RIMFSE） is presented. Firstly, fast sample entropy is employed to substitute traditional sample entropy, and the calculation cost is greatly reduced by improving the matching mechanism of reconstructed vectors. After that, the improved multiscale expansion method is applied to replace the traditional coarse-grained method, thereby avoiding the loss of amplitude information. Based on this, a new rotating machinery fault diagnosis method is proposed in combination with the max-relevance and min-redundancy（mRMR） method and the support vector machine（SVM） classifier. Two fault data sets of gearbox and bearing are used to verify the performance of the presented method; meanwhile, the presented method is compared with existing methods such as MSE, composite MSE（CMSE） and refined composite MSE（RCMSE）. The results show that compared with MSE, CMSE and RCMSE, the proposed method enjoys significant advantages in terms of robustness, calculation efficiency and recognition accuracy, thereby providing a new idea for rotating machinery fault diagnosis based on entropy feature.

The coastal salt pan of Shijiazhuang-Hengshui-Cangzhou-Huanghua Port Intercity Railway project is a highly corrosive environment. In order to ensure the long-term operation safety of the bridge structure, it is urgent to carry out relevant durability research and improve the durability of the bridge structure in this project. Through detailed investigation and analysis of the erosive environmental characteristics of the bridge engineering in this region, the exposed environment of the bridge structure is evaluated, durability design of the bridge concrete structure is carried out, and the following research results are presented. In view of the corrosive environment problems faced by railway engineering, the principle of overall design scheme is proposed. The mix ratio design of bridge pier pile-cap and castin- place pile in coastal corrosive environment is conducted, and the preparation technology of high durability concrete suitable for coastal salt pan corrosive environment is formed. The structural design of durability is studied, structural design principle and physical isolation design concept are proposed, the structural design control measures are proposed to improve durability, and the structural physical isolation measures are designed to effectively improve the durability of bridge structure. In view of the erosion characteristics of the project, additional strengthened protection measures are put forward, including the silane impregnation protection and the application of corrosion resistant reinforcement. The permeable formwork cloth is studied and applied to improve the construction quality and compaction of concrete. An exposure test station is set up in the engineering site and a wireless monitoring system for reinforced concrete durability is developed. The whole process of reinforcement corrosion monitoring is realized through the wireless monitoring system. Through the durability design and research of concrete structure of bridge in the coastal environment with strong corrosion, the purpose of improving the durability of railway concrete structure under the harsh service condition of coastal salt pan has been achieved. At the same time, The solid foundation has been laid for the later evaluation of the durability of the bridge structure during the service period. [ABSTRACT FROM AUTHOR]

Objective To investigate the change and its significance of serum neuron specific enolase (NSE)in children with febrile seizure (FS). Methods According to the frequency and duration of FS ,the research object was divided into four groups,i.e. group FS (simple FS,1 seizure lasting less than 15 min),group FS1 (complex FS,2 seizure lasting less than 15 min), group FS2 (complex FS, 1 seizure lasting more than 15 min) and the control group, 50 cases in each group. It was adopted radio-im-muni-assay to detect the serum NSE concentration. Results The difference had no statistical significance in the concentration of serum NSE on the 1st and 7th days of FS between simple group FS and the control group[( 15.16±1.68) , (14.96±1.65 )ng/mL respectively]vs.[( 15.00±1.88)ng/mL, (14.82±1.46)ng/mL respectively] (P>0.05), the concentrations of serum NSE in the group FS1, group FS2 on the 1st day was higher than those of the control group[( 19.90±3.63 )ng/mL vs. (27.44±9.34)ng/mL respectively]. There was statistical significance in difference (P<0.05). The concentrations of serum NSE in the group FS1, group FS2, whose FS duration was over 15 min was higher than those whose FS was repeated and short(>twice, <15 min)[(27.44±9.34 )ng/mL vs.( 19.90± 3.63)ng/mL], whose difference had statistical significance (P<0.05). The concentrations of serum NSE[(16.61±3.32)ng/mL] of the FS patients lasted over 15 min on the 7th day was higher than that of the control group, whose difference had statistical significance(P<0.05). Conclusion The serum NSE concentration after simple FS is normal. The neurons damage should be considered. The complex FS may lead to obvious neurons damage. The degree of long-time attack is heavier to neuron damage than that of repeated short-time occurrence. [ABSTRACT FROM AUTHOR]

Objective: To determine and analyze plasma ammonia concentration difference of the portal vein system and ramifications of rabbits and consequently guide selection of the portal vein in transjugular intrahepatic portosystemic shunt (TIPS) so that reduce shunt-induced hepatic encephalopathic incidence. To evaluate clinical significance of transjugular intrahepatic left branch of portal vein portosystemic shunt (TILPS) and to analyse hemodynamics of both branches of the portal vein and to observe long-term results in the prevention of encephalopathy., Methods: Blood samples in different portal vein branches of rabbits were collected and the plasma ammonia concentration was assayed and compared. The left branch of portal vein was used as the puncture site to perform TILPS and to keep away from the right branch of portal vein blood that contains nutrition and toxin., Results: Plasma ammonia content was superior in the mesenteric vein and higher than the portal vein branch, the splenic vein, and the vena cava. The right portal vein was above the left. Encephalopathy did not occur in all patients within 3 months. Of the 341 patients undergoing TILPS, encephalopathy occurred in only 5 patients (1.47%) and shunt abnormalities in 19 patients (5.57%) verified by venography during overall follow-up period., Conclusions: Selective left branch of the portal vein portosystemic shunt can decrease encephalopathy obviously and protect liver function.