Effects of Pitch of Array Punch on the Nanoimprinting

In this study, molecular dynamics (MD) are used to simulate the nanoimprinting behaviors of (001) Ni thin films using 3×3 array cuboid diamond punch. Different pitch of the punches was used to investigate the effect of the interaction among the forming pattern and the quality of the formed holes. Forming force was evaluated including normal and tractional force of the punch during pressing process. The dislocation behavior was also monitoring during the holes forming. The result showed that the pitch of the punch was 2w could get the best forming pattern.

Collagen Fibril Flow and Tissue Translocation Coupled to Fibroblast Migration in 3D Collagen Matrices

In nested collagen matrices, human fibroblasts migrate from cell-containing dermal equivalents into surrounding cell-free outer matrices. Time-lapse microscopy showed that in addition to cell migration, collagen fibril flow occurred in the outer matrix toward the interface with the dermal equivalent. Features of this flow suggested that it depends on the same cell motile machinery that normally results in cell migration. Collagen fibril flow was capable of producing large-scale tissue translocation as shown by closure of a ∼1-mm gap between paired dermal equivalents in floating, nested collagen matrices. Our findings demonstrate that when fibroblasts interact with collagen matrices, tractional force exerted by the cells can couple to matrix translocation as well as to cell migration.