A second printing head is used to deposit scaffolding-a sugar-based hydrogel .
第二个打印头用于沉淀支架----一种糖类的水凝胶。
Of course , that only makes sense for the particular hydrogel the team has in the lab now .
当然，独特的水凝胶已被研究团队在实验室做出来，这才有意义。
For tubular structures , such as blood vessels , the hydrogel is printed in the centre and around the outside of the ring of each cross-section before the cells are added .
对于像血管这样的管状结构，在细胞加入之前，水凝胶会打印到每个横截面的中心和外围环上。
So , for instance , in an environment with low ph the hydrogel fuses rather strongly , while at higher ph levels the bond is weakened .
