Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Frustration induced phases in migrating cell clusters   Collective motion of cells is common in many physiological processes,
including tissue development, repair, and tumor formation. Recent experiments
have shown that certain malignant cancer cells form clusters in a
chemoattractant gradient, which display three different phases of motion:
translational, rotational, and random. Intriguingly, all three phases are
observed simultaneously, with clusters spontaneously switching between these
modes of motion. The origin of this behavior is not understood at present,
especially the robust appearance of cluster rotations. Guided by experiments on
the motion of two-dimensional clusters in-vitro, we developed an agent based
model in which the cells form a cohesive cluster due to attractive and
alignment interactions but with potentially different behaviors based on their
local environment. We find that when cells at the cluster rim are more motile,
all three phases of motion coexist, in excellent agreement with the
observations. Using the model we can identify that the transitions between
different phases are driven by a competition between an ordered rim and a
disordered core accompanied by the creation and annihilation of topological
defects in the velocity field. The model makes definite predictions regarding
the dependence of the motility phase of the cluster on its size and external
chemical gradient, which agree with our experimental data. Our results suggest
that heterogeneous behavior of individuals, based on local environment, can
lead to novel, experimentally observed phases of collective motion.

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The categories of this paper are: astro-ph
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The categories of this paper are: atom-ph
2
The categories of this paper are: math
24
The categories of this paper are: dg-ga
30
The categories of this paper are: q-alg
0
The categories of this paper are: hep-ph
35
The categories of this paper are: mtrl-th
22
The categories of this paper are: chao-dyn
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The categories of this paper are: eess
34
The categories of this paper are: chem-ph
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The categories of this paper are: math-ph
29
The categories of this paper are: funct-an
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The categories of this paper are: cmp-lg
31
The categories of this paper are: ao-sci
18
The categories of this paper are: econ
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The categories of this paper are: nlin