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For studying the changing rules of the tribological properties and the related mechanisms of ta-C film in friction against several typical counterpart materials，a ta-C film with a thickness of approximately 1 μm was deposited by the laser-induced arc magnetic filtered vacuum cathode arc technology，and three kinds of counterpart balls with high hardness (WC，Al2O3 and 9Cr18) were used for friction and wear test.The microstructure and tribological properties of the ta-C film were systematically investigated by scanning electron microscopy，X-ray photoelectron spectroscopy，Raman spectrometer，surface profilometer，nano-indentation tester and ball-disk friction and wear equipment.Results showed that the ta-C film possessed extremely low friction coefficients in friction against all the three counterpart materials，and exhibited excellent antiwear and antifriction properties.When Al2O3 counterpart was employed，the friction coefficient of the film was the lowest with a value of around 0.11；when 9Cr18 counterpart was employed，the film showed the lowest wear rate of 4.0×10-7 mm3/(N·m)；and when WC counterpart was employed，the film showed the highest wear rate of 7.6×10-7 mm3/(N·m). Besides，the main wear mechanism of the film was abrasive wear，and a graphitized transfer film with the characteristics of carbon structure was detected on the surfaces of all the counterparts.

With the continuous increase in the number of users which access to ISP's edge devices,the amount of data needs to be processed has doubled,which causes the edge device to be overloaded,and affects the normal interaction of the virtual private network data constructed by the multi-protocol label switching and the border gateway protocol.At this stage,the MCE,HOPE and SDN solutions all have certain limitations in solving this problem:the MCE mode edge device interface does not support the creation of logical channels,the solution cannot be used;the HOPE mode causes problems such as routing loops;the number of concurrent sessions processed by a single SDN controller in the SDN mode cannot exceed 64 000.In response to the above problems,an edge device optimization solution based on dual-layer virtualization is proposed.This solution includes the following three basic steps:edge device virtualization,virtual private network tunnel establishment,and virtual private network information isolation.On this basis,the solution is optimized from the network model,the construction of the network resource pool and the splitting of the network resource pool.The performance of the solution is evaluated based on the experimental environment,and compared with the virtual private network constructed in the traditional way in terms of packet forwarding rate,manageability,and sca-lability.The analysis results show that the dual-layer virtual solution which is designed to construct a network resource pool can realize the unified scheduling and management of resources,effectively solve the overloaded problem of ISP's edge equipment,and also be an effective solution for building a virtual private network.

Aim: To investigate the expression and clinical significance of FOXO4 in colorectal cancer tissues., Methods: Immunohistochemistry assay was performed to detect the FOXO4 expression in 80 colorectal cancer and matched noncancerous tissues (18 cases in stage I, 32 in stage II, 24 in stage III and 6 in stage IV). The relationship between FOXO4 expression and the patients' clinicopathologic features including gender, differentiation and TNM staging was also analyzed., Results: The positive expression rate of FOXO4 protein in colorectal cancer tissues was 47.50%, which was significantly lower than that in matched noncancerous tissues (91.25%, P0.05) . however, there were significant differences of FOXO4 expression in tumor differentiation, TNM stage and lymph node metastasis (P<0.05)., Conclusion: The expression of FOXO4 was significantly decreased or deleted in colorectal cancer, indicating that FOXO4 may function as a tumor suppressor in the development and progression of colorectal cancer.