3,338 research outputs found
Estimation of Minkowski tensors from digital grey-scale images
It has been shown that local algorithms based on grey-scale images sometimes
lead to asymptotically unbiased estimators for surface area and integrated mean
curvature. This paper extends the results to estimators for Minkowski tensors.
In particular, asymptotically unbiased local algorithms for estimation of all
volume and surface tensors and certain mean curvature tensors are given. This
requires an extension of the known asymptotic formulas to estimators with
position dependent weights.Comment: 15 page
Energetics and efficiency of a molecular motor model
The energetics and efficiency of a linear molecular motor model proposed by
Mogilner et al. (Phys. Lett. 237, 297 (1998)) is analyzed from an analytical
point of view. The model which is based on protein friction with a track is
described by coupled Langevin equations for the motion in combination with
coupled master equations for the ATP hydrolysis. Here the energetics and
efficiency of the motor is addressed using a many body scheme with focus on the
efficiency at maximum power (EMP). It is found that the EMP is reduced from
about 10 pct in a heuristic description of the motor to about 1 per mille when
incorporating the full motor dynamics, owing to the strong dissipation
associated with the motor action.Comment: 23 pages, 6 figures, final version, appeared in J. Stat. Mech. P12001
(2013
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