Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Escherichia coli as a model active colloid: a practical introduction   The flagellated bacterium Escherichia coli is increasingly used
experimentally as a self-propelled swimmer. To obtain meaningful, quantitative
results that are comparable between different laboratories, reproducible
protocols are needed to control, `tune' and monitor the swimming behaviour of
these motile cells. We critically review the knowledge needed to do so, explain
methods for characterising the colloidal and motile properties of E.coli,
cells, and propose a protocol for keeping them swimming at constant speed at
finite bulk concentrations. In the process of establishing this protocol, we
use motility as a high-throughput probe of aspects of cellular physiology via
the coupling between swimming speed and the proton motive force.

24
The categories of this paper are: dg-ga
17
The categories of this paper are: q-fin
31
The categories of this paper are: ao-sci
36
The categories of this paper are: cmp-lg
10
The categories of this paper are: q-bio
30
The categories of this paper are: q-alg
28
The categories of this paper are: alg-geom
25
The categories of this paper are: patt-sol
12
The categories of this paper are: nucl-th
27
The categories of this paper are: comp-gas
6
The categories of this paper are: astro-ph
19
The categories of this paper are: eess
9
The categories of this paper are: nlin
0
The categories of this paper are: hep-ph
15
The categories of this paper are: nucl-ex
34
The categories of this paper are: chem-ph