No abstract

Hepatocellular carcinoma (HCC) is one of the most life-threatening diseases in the world. Members of the GTPase of the immunity-associated protein (GIMAP) family are important in regulating apoptosis in cancer cells. However, the basic mechanism of GIMAP in HCC remains to be fully elucidated. The present study was performed to investigate the dysregulation of GIMAP family members in HCC. The techniques of polymerase chain reaction analysis, immunohistochemistry and ELISA were used to analyze the expression of GIMAP5 and GIMAP6 in HCC tissues, in matched noncancerous tissue samples, and in blood samples obtained from patients with HCC and healthy subjects. It was found that the mRNA expression levels of GIMAP5 and GIMAP6 were significantly downregulated in the HCC tumor samples, compared with the levels of expression in the matched non-tumor tissue samples. Similarly, the mRNA expression levels of GIMAP5 and GIMAP6 were also significantly downregulated in the blood samples from patients with HCC, compared with the expression levels in the blood from healthy subjects. At the protein level, it was found that the GIMAP5 and GIMAP6 proteins were expressed at lower levels in the tumor tissue samples, compared with the matched normal tissue samples, and their expression levels were also lower in the blood samples from patients with HCC, compared with the blood samples from the healthy subjects. These data, demonstrating the downregulation of the mRNA and protein expression levels of GIMAP5 and GIMAP6 in the tumor tissues and blood of patients with HCC, suggested the involvement of GIMAP5 and GIMAP6 in the pathogenesis of HCC, and indicate their possible use as diagnostic markers for HCC.

For San-Xin gold and copper mine, deep blasting large block rate is high resulting in difficulty in transporting the ore out; secondary blasting not only increases blasting costs but is more likely to cause the top and bottom plate of the underground to become loose causing safety hazards. Based on the research background of Sanxin gold and copper mine, deep hole blasting parameters were determined by single-hole, variable-hole pitch, and oblique hole blasting tests, further using the inversion method to determine the optimal deep hole blasting parameters. Meanwhile, the PSO-BP neural network method was used to predict the block rate in deep hole blasting. The results of the study showed that the optimal minimum resistance line was 1.24–1.44 m, which was lower than 1.6–1.8 m in the original blasting design, which was one of the reasons for the higher blasting block rate. In addition, the PSO-BP deep hole blasting fragmentation prediction model predicts the block rate of the optimized blasting parameters and predicted a block rate of 6.83% after the optimization of hole network parameters. Its prediction accuracy is high, and the blasting parameter optimization can effectively reduce the block rate. It can reasonably reduce the rate of large pieces produced by blasting, improve blasting efficiency, and save blasting costs for enterprises. The result has wide applicability and can provide solutions for underground mines that also have problems with blasting large block rate.

Mining of closely spaced multilayer orebodies brings the problems of significant disturbance between adjacent mining layers and drastic structural changes in surrounding rock, which brings the need for a more effective stope support method. Previous research has made sound analysis on filling or bolt support, but neither of them can solely provide ideal support effects. Thus, a novel bolt-filling support method is proposed by utilizing the synergistic effect of rock bolts (cable bolts) and filling. Numerical simulation and similarity experiments were conducted in this research to analyze the support effect of this method for multilayer ore mining. For numerical simulation, the distinct-element modelling framework PFC2D (Particle Flow Code in 2 Dimensions) was applied for four support scenarios based on the calibration of the microscopic parameters of particles in vanadium shale ores. The numerical simulation results show that the number of fractures decreases from 1311 without support through 652 with 95% filling support to 410 with bolt-filling support, which is resulted from the redistribution of the force chains due to support change. On the other hand, a 300 cm ×180 cm × 40 cm similarity model with a geometry similarity constant of 100 was established based on the 4# rock layer profile of Mount Shangheng. Two parts of similarity experiments were conducted to investigate the strains around the stopes in multi-layer ore mining for three support scenarios. The experiment results prove that the highest strain is in the center of the roof on the upper goaf, and the roof-bolt filling support induces smaller strains than zero support and conventional filling support. Finally, an effective bolt-filling support system has been developed and validated, which can improve the safety and the stability of the roofs and interlayers during the mining process of closely spaced multilayer orebody by reducing the overall load and fractures in surrounding rock.