Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Dislocations and cracks in generalized continua   Dislocations play a key role in the understanding of many phenomena in solid
state physics, materials science, crystallography and engineering. Dislocations
are line defects producing distortions and self-stresses in an otherwise
perfect crystal lattice. In particular, dislocations are the primary carrier of
crystal plasticity and in dislocation based fracture mechanics.

22
The categories of this paper are: chao-dyn
2
The categories of this paper are: math
31
The categories of this paper are: ao-sci
3
The categories of this paper are: physics
24
The categories of this paper are: dg-ga
20
The categories of this paper are: acc-phys
16
The categories of this paper are: stat
10
The categories of this paper are: q-bio
7
The categories of this paper are: hep-th
6
The categories of this paper are: astro-ph
8
The categories of this paper are: hep-ex
9
The categories of this paper are: nlin
17
The categories of this paper are: q-fin
23
The categories of this paper are: solv-int
33
The categories of this paper are: plasm-ph
11
The categories of this paper are: hep-lat