RESUMEN
The problem that it is difficult to balance vehicle stability and economy at the same time under the starting steering condition of a four-wheel independent drive electric vehicle (4WIDEV) is addressed. In this paper, we propose a coordinated optimal control method of AFS and DYC for a four-wheel independent drive electric vehicle based on the MAS model. Firstly, the angular velocity of the transverse pendulum at the center of mass and the lateral deflection angle of the center of mass are decoupled by vector transformation, and the two-degree-of-freedom eight-input model of the vehicle is transformed into four two-degree-of-freedom two-input models, and the reduced-dimensional system is regarded as four agents. Based on the hardware connection structure and communication topology of the four-wheel independent drive electric vehicle, the reduced-dimensional model of 4WIDEV AFS and DYC coordinated optimal control is established based on graph theory. Secondly, the deviation of the vehicle transverse swing angular velocity and mass lateral deflection angle from their ideal values is oriented by combining sliding mode variable structure control (SMC) with distributed model predictive control (DMPC). A discrete dynamic sliding mode surface function is proposed for the ith agent to improve the robustness of the system in response to parameter variations and disturbances. Considering the stability and economy of the ith agent, an active front wheel steering and drive torque optimization control method based on SMC and DMPC is proposed for engineering applications. Finally, a hardware-in-the-loop (HIL) test bench is built for experimental verification, and the results show that the steering angle is in the range of 0-5°, and the proposed method effectively weighs the system dynamic performance, computational efficiency, and the economy of the whole vehicle. Compared with the conventional centralized control method, the torque-solving speed is improved by 32.33 times, and the electrical consumption of the wheel motor is reduced by 16.6%.
RESUMEN
The present study was aimed to investigate the effect of 2-amino-4-(1-piperidine) pyridine on migration and invasion of colon cancer cells. Treatment of colon cancer cells with 2-amino-4-(1-piperidine) pyridine reduced viability in concentration-based manner. The migration potential of HCT116 and HT29 cells was also suppressed on treatment with 2-amino-4-(1-piperidine) pyridine. In HCT116 and HT29 cells, apoptotic cell proportion was increased significantly by 2-amino-4-(1-piperidine) pyridine treatment. The expression of EMT and Vimentin in HCT116 and HT29 cells was reduced markedly on treatment with 2-amino-4-(1-piperidine) pyridine. The expression of E-cadherin was increased in HCT116 and HT29 cells by 2-amino-4-(1-piperidine) pyridine treatment. Treatment with 2-amino-4-(1-piperidine) pyridine reduced the expression of FOXA2 in HCT116 and HT29 cells. The 2-amino-4-(1-piperidine) pyridine treatment reduced growth of tumor in vivo in mice model. In summary, 2-amino-4-(1-piperidine) pyridine treatment inhibits colon cancer cell proliferation through down-regulation of FOXA2 expression. Therefore, 2-amino-4-(1-piperidine) pyridine can be used for the treatment of colon cancer.
RESUMEN
The activation of mammalian target of rapamycin (mTOR) has been reported in tumor development, but the role of mTOR in colorectal carcinomas remains unclear. The aim of the present study was to investigate the significance of mTOR and its downstream effector 70 kDa ribosomal protein S6 kinase (P70S6K) in human colorectal carcinomas. The phosphorylated (p-)mTOR and p-P70S6K proteins were examined by immunohistochemistry performed on tissue microarray containing tissue samples obtained from colorectal carcinoma (n=111), adenomatous polyps (n=40) and normal colonic mucosa (n=40), with a comparison between the expression of these proteins and the clinicopathological parameters of patients with carcinomas. The positive expression rates of p-mTOR and p-P70S6k were 60.4 and 65.8%, respectively, in colorectal carcinoma tissue, which was significantly increased compared with the tissue from adenomatous polyps (27.5 and 20%, respectively) and normal colonic mucosa (10.0 and 5.0%, respectively) (P<0.05). Overexpression of the p-mTOR and p-P70S6K proteins was significantly associated with the tumor-node-metastasis stage, the occurrence of distal and lymph node metastasis and the degree of differentiation. Aberrant expression of p-mTOR and p-P70S6K may contribute to the pathogenesis, growth, invasion and metastasis of colorectal carcinoma. The phosphorylation of these proteins was considered to be a promising marker to indicate the aggressive behaviors and prognosis of colorectal carcinomas. The overexpression of the mTOR/P70S6K signaling pathway may play an important role in colorectal carcinoma carcinogenesis. The expression of p-mTOR and p-P70S6K was considered as a promising marker to indicate the aggressive behaviors and prognosis of human colorectal carcinomas.