Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Bio-mimic four-dimensional printing of nanostructured interactive
  hydrogels   Nature has exhibited numerous soft-interactive botanical or zoological
systems with self-adaptivenss or reconfigurable shape, however, artificial
micro/nano materials of same merit are formidable due to material/structural
limitations, posing multidimensional challenges to current chemical/physical
fabrications. Here, we propose a new nanostructured hydrogel by
four-dimensional (4D) printing for function integration and dimension
reduction. The cross-linked matrix relaxes or contracts in robust hierarchical
heterojunction to eliminate interface issues of dual-layer desgin.

29
The categories of this paper are: funct-an
2
The categories of this paper are: math
14
The categories of this paper are: math-ph
8
The categories of this paper are: hep-ex
7
The categories of this paper are: hep-th
30
The categories of this paper are: q-alg
23
The categories of this paper are: solv-int
27
The categories of this paper are: comp-gas
28
The categories of this paper are: alg-geom
0
The categories of this paper are: hep-ph
21
The categories of this paper are: adap-org
37
The categories of this paper are: supr-con
11
The categories of this paper are: hep-lat
16
The categories of this paper are: stat
1
The categories of this paper are: cs
26
The categories of this paper are: bayes-an