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The dovetail of ceramic matrix composites（CMC）turbine blade is the key to the assembly and ability to withstand centrifugal loads of the blade. In order to study the mechanical behaviour of the blade dovetail prepared by the melt infiltration（MI）method under the tensile load in the radial direction of rotating，and verify the influence of the internal quality of the dovetail on its static tensile strength and failure mode，the CMC high pressure turbine dovetail element specimens were designed and fabricated，and a uniaxial static tensile test was conducted，the internal quality of the test specimens was scanned using non-destructive X-ray CT. The test process was monitored using DIC and acoustic emission method. The results show that the CMC dovetail is able to maintain in complete contact under uniaxial static tensile loads，and its static strength and failure are very sensitive to its internal quality，especially to the delamination defects. When there are no delamination defects in the dovetail，the damage generally starts from the neck and quickly spreads，the damage starting load is near the maximum fracture load，and the fracture surface is zigzag. When there are delamination defects in the dovetail，the fracture starts from the defects，and the delamination gradually spread and cause the fracture surface of the dovetail，the damage starting load is decreased by 99.05%，and the maximum failure load is decreased by 14.29% compared to the case of no delamination defects，and the fracture surface is consistent with the delamination defects.

The development of the cultural industry is now at the top of its national plan. When it comes to the development of the cultural industry, the most important thing is to speed up the transformation of commercial cultural institutions into businesses. This will help to rebuild the market players in the cultural industry, as well as integrate the social resources involved in the development of the cultural industry, form the advantages of resource combination, and build a platform for the cultural industry to grow. It is a good idea to have a system and mechanism in place to help the cultural industry grow, as well as a social environment and an undertaking carrier. Data resources can help drive the integration of resources in our country's cultural and creative industries, as well as the optimization of industrial structure, intelligent transformation, and total growth. People who work in the cultural industry can predict rough data and get the essence out. They can calmly and objectively make decisions about data, and they can use data speed and diversity to drive content creation, communication innovation, and consumption upgrades in the cultural industry. In this study, large cultural businesses lead the way when it comes to integrating cultural industry resources based on data mining. Cultural industry parks are the places where clusters of businesses are built. To make a cultural industry chain, it looks at what customers do not say about their needs and looks at the resources in the industry to make sure it is a good fit. The government should help cultural businesses by making it easier for them to do business. This will help our country's cultural industry be more competitive. [ABSTRACT FROM AUTHOR]

MicroRNAs play an important role in tumor development and progression. Tumor growth is closely associated with glucose metabolism. Specifically, tumor cells produce energy (ATP) under aerobic and anaerobic conditions through glycolysis and metabolites, such as lactic acid and ATP, as a result of the Warburg effect. However, the transport of glucose into cells depends on protein transporters in the cell membrane. Therefore, this area has recently become a topic of interest for research on targeted cancer therapy. We found that miRNA-451 inhibits the phosphatidylinositol-3 kinase (PI3K)/Akt signaling pathway to modify the biological behavior of glioma cells. Inhibiting the PI3K/Akt pathway may prevent glucose-addicted cancer cells from performing glycolysis. Akt directly affects glycolysis by regulating the localization of the glucose transporter 1 (GLUT1). However, how miRNA-451 regulates glucose transporters on the cell membrane and affects the regulatory mechanisms of glucose metabolism in glioma cells remains unclear. Consequently, we predict and verify related gene protein interactions. By targeting CAB 39, miRNA-451 likely triggers the LKB1/AMPK/PI3K/AKT pathway, which regulates GLUT1, to inhibit the glucose metabolism of, reduce the energy supply to, and inhibit the proliferation and invasion of glioma cells. Our results suggest a new direction for the treatment of glioma. [ABSTRACT FROM AUTHOR]

The damage coupling effects of a two-dimensional carbon fibre-reinforced silicon carbide composite (2D-C/SiC) under proportional loading conditions were investigated using off-axial tensile and compressive tests. The applied load was translated into three proportional stress components in the fibre bundle directions of the composite. The tensile, compressive and shear stress–strain behaviours of the composite in the axial directions were obtained and analysed by mounting strain gauges on the tested specimens. Based on the stress–strain behaviours of the composite subjected to a single axial load, the coupling effects between damage caused by different stress components were characterised and analysed based on the strain deviations. Finally, SEM (scanning electron microscope) techniques were used to identify the damage mechanisms and failure modes of the tested specimens. The micro-damage model was built to explain the damage coupling effects of the composite. In addition, the influences of the damage coupling effects on the mechanical properties of the material were obtained. [ABSTRACT FROM AUTHOR]

Under monotonic, non-reverse and reverse cyclic load conditions, the evolution of the in-plane shear damage and the stress–strain behaviours of a two-dimensional Hi-Nicalon fibre-reinforced silicon carbide composite (2D-SiC/SiC) were investigated using Iosipescu tests. The stress-dependent shear damage evolution of the material was characterised by strain data, which were obtained from strain gauges mounted on the tested specimens. Under cyclic shear loading, the shapes of the hysteresis loops were explained by the fibre bending–bearing mechanism and the crack closure effect. The shear strengths under various loading procedures were also compared and analysed. Finally, SEM (scanning electron microscope) techniques were used to identify the shear failure modes of the tested material. [ABSTRACT FROM AUTHOR]

In order to reveal the damage evolution and failure mechanism of ceramic matrix composites (CMCs), in-situ X-ray CT compression tests of plain weave SiCf/SiC composites were conducted, and the CT data during loading and after failure were obtained. Displacement and strain distributions of the material were evaluated by the digital volume correlation (DVC) technology. The three-dimensional visual model of the composite was created by using image processing software. The spatial distributions of tow split and other damages were segmented by the deep learning algorithm. The qualitative and quantitative analysis of compression damage evolution were performed. The results show that there is a relatively large expansion induced by barreling in the thickness direction and a little shrinkage in the width direction during the unidirectional compression, while the barreling in the thickness direction is the main reason to trigger compressive damages of the material. Damages such as matrix falling-off at surface, tow split, delamination, will occur as the compression was approaching the ultimate load. Fiber kinking results in the final compressive failure of the material, while an obvious V-shaped shear band is observed in the fracture. The analysis of compressive damage evolution of plain weave SiCf/SiC shows that the DVC technology and deep learning-based image segmentation methods could effectively reveal the compressive damage evolution mechanism of ceramic matrix composites.

The paper presents the investigation of microstructures and tensile damage evolution of plain weave SiC fibre reinforced SiC matrix (SiC/SiC) composites using X-ray computed tomography (CT). A miniature high-precision in situ X-ray CT test fixture has been developed to conduct micro X-ray CT in-situ tensile tests. Through the image reconstruction of the CT data, the actual microstructures and the damage evolution of the material under six successive loading levels have been revealed precisely. Deep-learning-based image segmentation has been employed to recognise material damages, including transverse matrix cracking, longitudinal matrix cracking, and fibre pull-outs. Three-dimensional rendering models of these damages have been created to quantify the damage initiation and evolution. Both transverse and longitudinal matrix cracking initiates and propagates gradually at the intermediate loading level, but rapidly at the high loading level. The volume fraction of longitudinal matrix cracks is much larger than that of its transverse counterpart. It indicates that the longitudinal matrix cracking is much severer damage than transverse tracking. The lengths of fibre pull-outs at the fracture surface of fibre tows are in a broad range and on average they are in the order of a hundred microns. [ABSTRACT FROM AUTHOR]