Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Temperature and force dependence of nanoscale electron transport via the
  Cu protein Azurin   The mechanisms of solid-state electron transport (ETp) via a monolayer of
immobilized Azurin (Az) was examined by conducting probe atomic force
microscopy (CP-AFM), both as function of temperature (248 - 373K) and of
applied tip force (6-12 nN). By varying both temperature and force in CP-AFM,
we find that the ETp mechanism can alter with a change in the force applied via
the tip to the proteins. As the applied force increases, ETp via Az changes
from temperature-independent to thermally activated at high temperatures. This
is in contrast to the Cu-depleted form of Az (apo-Az), where increasing the
applied force causes only small quantitative effects, that fit with a decrease
in electrode spacing. At low force ETp via holo-Az is temperature-independent
and thermally activated via apo-Az. This observation agrees with
macroscopic-scale measurements, thus confirming that the difference in ETp
dependence on temperature between holo- and apo-Az is an inherent one that may
reflect a difference in rigidity between the two forms. An important
implication of these results, which depend on CP-AFM measurements over a
significant temperature range, is that for ETp measurements on floppy systems,
such as proteins, the stress applied to the sample should be kept constant or,
at least controlled during measurement.

37
The categories of this paper are: supr-con
16
The categories of this paper are: stat
36
The categories of this paper are: cmp-lg
20
The categories of this paper are: acc-phys
1
The categories of this paper are: cs
18
The categories of this paper are: econ
13
The categories of this paper are: quant-ph
35
The categories of this paper are: mtrl-th
21
The categories of this paper are: adap-org
17
The categories of this paper are: q-fin
23
The categories of this paper are: solv-int
30
The categories of this paper are: q-alg
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The categories of this paper are: atom-ph
12
The categories of this paper are: nucl-th
9
The categories of this paper are: nlin
7
The categories of this paper are: hep-th