Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Decoupling of dipolar and hydrophobic motions in biological membranes   Cells use homeostatic mechanisms to maintain an optimal composition of
distinct types of phospholipids in cellular membranes. The hydrophilic dipolar
layer at the membrane interface, composed of phospholipid headgroups, regulates
the interactions between cell membranes and incoming molecules, nanoparticles,
and viruses. On the other hand, the membrane hydrophobic core determines
membrane thickness and forms an environment for membrane-bound molecules such
as transmembrane proteins. A fundamental open question is to what extent the
motions of these regions are coupled and, consequently, how strongly the
interactions of lipid headgroups with other molecules depend on the properties
and composition of the membrane hydrophobic core. We combine advanced
solid-state nuclear magnetic resonance spectroscopy methodology with
high-fidelity molecular dynamics simulations to demonstrate how the rotational
dynamics of choline headgroups remain nearly unchanged (slightly faster) with
incorporation of cholesterol into a phospholipid membrane, contrasting the well
known extreme slowdown of the other phospholipid segments. Notably, our results
suggest a new paradigm where phospholipid headgroups interact as quasi-freely
rotating flexible dipoles at the interface, independent of the properties in
the hydrophobic region.

24
The categories of this paper are: dg-ga
11
The categories of this paper are: hep-lat
35
The categories of this paper are: mtrl-th
32
The categories of this paper are: atom-ph
37
The categories of this paper are: supr-con
12
The categories of this paper are: nucl-th
31
The categories of this paper are: ao-sci
16
The categories of this paper are: stat
13
The categories of this paper are: quant-ph
18
The categories of this paper are: econ
0
The categories of this paper are: hep-ph
1
The categories of this paper are: cs
21
The categories of this paper are: adap-org
9
The categories of this paper are: nlin
19
The categories of this paper are: eess
20
The categories of this paper are: acc-phys