Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Getting in shape and swimming: the role of cortical forces and membrane
  heterogeneity in eukaryotic cells   Recent research has shown that motile cells can adapt their mode of
propulsion to the mechanical properties of the environment in which they find
themselves--crawling in some environments while swimming in others. The latter
can involve movement by blebbing or other cyclic shape changes, and both
highlysimplified and more realistic models of these modes have been studied
previously. Herein we study swimming that is driven by membrane tension
gradients that arise from flows in the actin cortex underlying the membrane,
and does not involve imposed cyclic shape changes. Such gradients can lead to a
number of different characteristic cell shapes, and our first objective is to
understand how different distributions of membrane tension influence the shape
of cells in an inviscid quiescent fluid. We then analyze the effects of spatial
variation in other membrane properties, and how they interact with tension
gradients to determine the shape. We also study the effect of fluid--cell
interactions and show how tension leads to cell movement, how the balance
between tension gradients and a variable bending modulus determine the shape
and direction of movement, and how the efficiency of movement depends on the
properties of the fluid and the distribution of tension and bending modulus in
the membrane.

9
The categories of this paper are: nlin
37
The categories of this paper are: supr-con
6
The categories of this paper are: astro-ph
30
The categories of this paper are: q-alg
17
The categories of this paper are: q-fin
28
The categories of this paper are: alg-geom
1
The categories of this paper are: cs
34
The categories of this paper are: chem-ph
26
The categories of this paper are: bayes-an
13
The categories of this paper are: quant-ph
27
The categories of this paper are: comp-gas
22
The categories of this paper are: chao-dyn
32
The categories of this paper are: atom-ph
31
The categories of this paper are: ao-sci
2
The categories of this paper are: math
7
The categories of this paper are: hep-th