This study characterized human umbilical vein endothelial cell ͑HUVEC͒ adhesion, proliferation, and gene expression on bilayered polyelectrolyte coatings composed of an outermost layer of glycosaminoglycans ͑hyaluronan, heparin, or chondroitin sulfate͒, with an underlying layer of poly-L-lysine or chitosan. The proportion of cells that adhered to the various polyelectrolyte coatings after 1 and 2 h incubations was quantified by the WST-8 assay. Interchanging poly-L-lysine with chitosan resulted in significant differences in cellular adhesion to the outermost glycosaminoglycan layer after 1 h, but these differences became insignificant after 2 h. The proliferation of HUVEC on the various bilayered polyelectrolyte coatings over 10 days was characterized using the WST-8 assay. Regardless of whether the underlying layer was poly-L-lysine or chitosan, HUVEC proliferation on the hyaluronan outermost layer was significantly less than on heparin or chondroitin sulfate. Additionally, it was observed that there was more proliferation with poly-L-lysine as the underlying layer, compared to chitosan. Subsequently, real-time polymerase chain reaction was used to analyze the expression of seven genes related to adhesion, migration, and endothelial function ͑VWF, VEGFR, VEGFA, endoglin, integrin-␣5, ICAM1, and ICAM2͒ by HUVEC cultured on the various bilayered polyelectrolyte coatings for 3 days. With poly-L-lysine as the underlying layer, biologically significant differences ͑greater than twofold͒ in the expression of VWF, VEGFR, VEGFA, endoglin, and ICAM1 were observed among the three glycosaminoglycans. With chitosan as the underlying layer, all three glycosaminoglycans displayed biologically significant differences in the expression of VWF and VEGFR compared to the chitosan control. CT-HA displayed the highest level of expression of VWF, whereas expression levels of VEGFR were almost similar among the three glycosaminoglycans.

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A new type of hydro-viscous drive (HVD) winch was designed by combining with differential gear train and HVD. It could meet the requirements of inclined hoist. In order to achieve good control properties, though dynamic modeling and simulation, the output moment curves of HVD device were obtained, then, the working processes of starting, braking and lowering weight were analyzed. Research results provide a theoretical basis for making control strategies for HVD winch. Finally, the starting process of HVD winch was studied in the experimental device; the result indicated that the starting curve of HVD winch efficiently in accordance with Harrison curve.

Based on the requirements of torque transmission for stability and saturation magnetization of magnetorheological fluid (MRF), an orthogonal test was designed to arrange for the preparation of MRF. MRF was prepared by chemical co-precipitation method, in which Fe3O4 nano-particles were coated with polyethylene glycol(PEG-4000). The size and distribution of particles were observed by transmission electron microscope (TEM). The saturation magnetization was measured by vibrating sample magnetometer(VSM). Through analysis of variance of orthogonal test,an optimal method for preparing a highly stable and saturation magnetization MRF was summarized. Four main parameters in preparation of MRF were discussed, including the rate of amount of substance between Fe2+and Fe3+, the rate of amount of substance between PEG-4000 and Fe2+, reaction time and the reaction temperature. It has important practical significance on the study of magnetorheological transmission device.