Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A Note on a Nonlocal Nonlinear Reaction-Diffusion Model   We give an application of the Crandall-Rabinowitz theorem on local
bifurcation to a system of nonlinear parabolic equations with nonlocal reaction
and cross-diffusion terms as well as nonlocal initial conditions. The system
arises as steady-state equations of two interacting age-structured populations.

1
The categories of this paper are: cs
6
The categories of this paper are: astro-ph
20
The categories of this paper are: acc-phys
0
The categories of this paper are: hep-ph
8
The categories of this paper are: hep-ex
34
The categories of this paper are: chem-ph
24
The categories of this paper are: dg-ga
28
The categories of this paper are: alg-geom
36
The categories of this paper are: cmp-lg
32
The categories of this paper are: atom-ph
30
The categories of this paper are: q-alg
29
The categories of this paper are: funct-an
19
The categories of this paper are: eess
26
The categories of this paper are: bayes-an
12
The categories of this paper are: nucl-th
14
The categories of this paper are: math-ph