Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Lipid Bilayer Hydrodynamic Drag   The hydrodynamic drag at a lipid bilayer surface determines in part the flow
properties of suspensions of cells and liposomes. Given the fluidity of lipid
bilayers, it is not obvious a priori whether solid-like no-slip, liquid-like
no-stress, or intermediate boundary conditions apply at the water-bilayer
interface. Though no-slip conditions have been widely assumed for many decades,
this fundamental aspect of membrane rheology has, to our knowledge, never been
directly measured for free bilayers. We applied light sheet fluorescence
microscopy to image freely diffusing phospholipid vesicles and determined the
hydrodynamic drag coefficient $C \pi \eta R$, where $\eta$ is the external
fluid viscosity, $R$ is the vesicle radius, and the dimensionless $C$
characterizes the flow boundary condition. We find that $C = 5.92 \pm 0.13$
(stat.) $\pm 0.16$ (syst.), matching the theoretical value of $C=6$ for a
no-slip boundary and far from the $C=4$ value for a zero shear stress boundary

18
The categories of this paper are: econ
25
The categories of this paper are: patt-sol
21
The categories of this paper are: adap-org
8
The categories of this paper are: hep-ex
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The categories of this paper are: ao-sci
7
The categories of this paper are: hep-th
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The categories of this paper are: quant-ph
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The categories of this paper are: solv-int
4
The categories of this paper are: cond-mat
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The categories of this paper are: plasm-ph
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The categories of this paper are: stat
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The categories of this paper are: nlin
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The categories of this paper are: chao-dyn
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The categories of this paper are: chem-ph
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The categories of this paper are: astro-ph
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The categories of this paper are: alg-geom