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Background: Postoperative complications and mortality of hip fracture in the elderly are relatively high. General anesthesia and regional block anesthesia are commonly used anesthesia methods. There is still a big controversy about the comparison of the influence of the two anesthesia methods on the outcome of patients. Therefore, the purpose of this randomized controlled trial was to evaluate the effect of regional and general anesthesia on postoperative outcomes of hip fractures in the elderly. Methods: This is a prospective randomized controlled trial to compare the effects of regional anesthesia and general anesthesia on postoperative outcome of hip fractures in the elderly. Approved by the Clinical Research Society of our hospital. Patients were randomly divided into regional block anesthesia group and general anesthesia group. The difference in postoperative mortality rate and postoperative complication rate between the two groups will be compared. We will use SPSS 24.0 statistical software to analyze the data. Discussion: This study will compare the effects of regional anesthesia and general anesthesia on the postoperative outcome of hip fracture in the elderly. The results of this study will provide clinical evidence for the reasonable choice of anesthesia in elderly patients with hip fracture surgery.

To improve the crack propagation resistance of YSZ thermal barrier coatings during the thermal cycle, three kinds of thermal barrier coatings were prepared by atmospheric plasma spraying: YSZ, AlBOw-modified YSZ and BNW-modified YSZ. SEM, EDS and XRD were used to analyse the morphology, composition and phase composition of the sprayed powder and coating section. The phase structures of the YSZ, YSZ+AlBOw and YSZ+BNw coatings were t' phase. The cross-section of the coating presents a layered structure with pores inside. The porosity values of the YSZ, YSZ+AlBOw and YSZ+BNw coatings are 10.33%, 14.17% and 12.52%, respectively. The thermal shock resistance of three groups of coatings after 5 min at 1000 °C was analysed. The failure behaviour of the coatings after several thermal cycles was studied. The results show that the thermal shock resistance of the coatings with AlBOw is slightly lower than that of the YSZ coatings. The thermal shock resistance of the BNw coatings is 62.2% higher than that of the YSZ coatings. The whisker inhibits the crack propagation and prolongs the life of the coatings via crack deflection, whisker pull-out and whisker bridging.

In this paper, a new underwater processing technology was proposed, called underwater wet laser cladding (UWLC). Protective material assisted UWLC was provided to increase the processed water depth of UWLC and promote the quality of UWLC coatings without changing the laser power. For comparison, the direct UWLC and protective material assisted UWLC were performed under various water depths with uniform experimental parameters. The UWLC processes under water depth of 15 mm were studied in detail. The blue-purple plasma appears during the direct UWLC processes leading to the failure of UWLC. The mental plume appears during the protective material assisted UWLC processes. In addition, the protective material assisted UWLC is more likely to succeed by increasing the content of protective material. The 316L stainless steel coatings were successfully prepared by protective material assisted UWLC. The microstructure of the 316L coatings by protective material assisted UWLC is well in agreement with 316L coatings prepared by laser cladding in air, while the 316L coating by direct UWLC is mainly composed of columnar dendrites. Moreover, the corrosion resistance of 316L coating by direct UWLC in 3.5 wt.% NaCl solutions is improved markedly by applying protective material. The energy loss in the process of underwater wet laser processing is significantly reduced through the protective material assisted method, which provides meaningful theoretical support for underwater wet laser repair.

In the conversion coatings, some uniformly distributed micro surface cracks always occur but the surface cracks behavior is rarely studied due to the frequent initiation in the real test conditions. In this work, computer simulation of micro surface cracks behavior and internal stresses generated in the anhydrous chemical conversion coating was carried out using the finite element method with the help of ABAQUS software. The Mises stress distribution, S11 stress variation, and the stress-time curves were obtained. The results show that the internal stresses generated in the conversion coating increase obviously with increasing time, and the stresses at the center and boundary of coating pieces are bigger than the ones in other areas while the S11 stresses around the center are bigger than the ones near the boundary. The cracks at the interface of coating pieces develop gradually and are as V-type cracks finally. The width of crack mouth opened is different since the contraction degree of each coating piece is different.