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Nerve growth factor (NGF) binds to TrkA and forms a NGF/TrkA complex at the cell surface, which is then internalized into signaling endosomes and promotes neuronal survival and neurite outgrowth. The small GTPase Rab5 is reported to localize on the plasma membrane and early endosomes, regulating endosome fusion. It was reported that endogenous Rab5 function may need to be suppressed during NGF-induced neurite outgrowth and cell differentiation. Two Rab5 homologs (MoRab5A: MGG_06241 and MoRab5B:MGG_01185) were characterized from the rice blast fungus Magnaporthe oryzae, and MoRab5B was identified as the Rab5 ortholog promoting early endosomal fusion, while MoRab5A specialized to perform a non-redundant function in endosomal sorting. In this study, we examined whether MoRab5A and MoRab5B play different roles in NGF-induced neurite outgrowth and cell differentiation in PC12 cells (a rat pheochromocytoma cell line). Our data showed that MoRab5B is a negative regulator of NGF signaling and neurite outgrowth in PC12 cells, similar to human Rab5 (hRab5). MoRab5B:WT inhibits NGF signaling-dependent neurite outgrowth while the dominant-negative MoRab5B mutant (MoRab5B:DN) enhances NGF signaling and neurite outgrowth. In contrast, MoRab5A:WT and MoRab5A:DN both significantly promote NGF-induced neurite outgrowth, indicating that MoRab5B is more similar to hRab5 than MoRab5A in the regulation of NGF signal transduction.

Through traditional corrosion method of aluminum alloy weld could only get a black-and-white metallographic structure. Color metallographic structure could be got by using color metallographic technique, which could improve discrimination of metallographic structure. The welding test pieces were got by using A7N01 and A6N01 aluminum sheets as base metal and E5356 and E4043 as welding wire. Through sampling, mounting, grinding and polishing process, metallographic specimens were obtained. Contrast test of aluminum alloy specimens was investigated. Conventional Keller’s reagent corrosion results showed the grain outline was not very clear and the grain boundary was fuzzy. Color metallographic corrosion results showed both the grain outline and boundary were very clear. Grains of different orientation and composition segregation presented different color. So color can be used to distinguish orientation and composition segregation. Color metallographic technique was better than black-and-white metallographic technique to observe the metallographic structure.

3D shape of the weld pool surface can be used to infer the penetration state of the weld pool, which has an importance influence on weld quality. In this paper, a novel stereo camera system that used only one camera and a biprism placed in front of the lens was applied to capture virtual image pair of the weld pool surface. The most advantage of the system setup is that corresponding points lie on the same scan line automatically, i.e. the stereo image pair is self rectified. The calibration of the system was done using plane pattern by Zhang’s algorithm and the standard SSD stereo matching algorithm was applied to find the corresponding points in the left and right image. The reconstructed 3D shape of the weld pool surface during base current period of P-GMAW by the system has shown that the technique has potential application for control of weld process