传统手工艺的研究路径与记述方式——从《华县皮影》与《回望手艺》谈起

赵农教授不仅是知名艺术设计史论家,还是民艺研究的代表性学者,《华县皮影》与《回望手艺》已经出版近15年,在他关于传统手工艺的研究路径方法及记述方式中贯穿了“人本民生”思想与“文化生态”理论,直至今日依然对当代民艺研究具有重要的指导作用。

Recombinant human bone morphogenetic protein-7 expressed from CHO cells possessing the activity of bone-induced in vitro

Objective To express the recombinant human bone morphogenetic protein-7 (rhBMP-7) in Chinese hamster ovary (CHO) cells and to establish the in vitro biological activity assay of rhBMP-7. Methods Human BMP-7 cDNA was subcloned into pcDNA3.1 mammalian expression vector and transfected to CHO cells by using the lipofectin transfection method. BMP-7 expression cell culture supernatants were harvested and purified for target protein. To analyze the bioactivity of the secreted rhBMP-7, a novel in vitro assay was established by measuring its alkaline phosphatase (ALP) stimulating of osteoblast cell line, W-20-17. Results BMP-7 stably expressing cell clone was selected, which secreted mature disulfide-linked homodimer form of hBMP-7 and had an apparent molecular weight of 36kDa. rhBMP-7 with >95% purity was obtained using 3 step chromatography method. Bioactivity assay showed that the purified protein specifically stimulated W-20-17 cell producing ALP, with a 4-fold increase of ALP activity at 100ng/ml or more, and the EC50 of 15.6ng/ml. Conclusion Purified rhBMP-7 from this CHO expression system has significant biological activity in induction of osteoblast phenotype, which demonstrates potential bone regeneration activity.

一种基于超体素与区域生长的机载点云屋顶平面分割方法

区域生长算法存在两个问题:(1)难以选择出鲁棒性强的种子点;(2)难以得到准确的边界。针对此问题,提出一种基于超体素进行区域生长和拓扑结构边界优化的屋顶平面分割方法。针对问题(1),通过超体素方法将点云分为初始平面片集合,然后通过区域生长算法对平面片进行聚类得到初始平面。针对问题(2),对得到的初始平面进行拓扑化,构建并优化平面之间的相邻关系,对非平面点进行重分类以实现平面边界优化。结果表明,使用该方法能够提取出高质量的屋顶平面。