Heat and work distributions for mixed Gauss-Cauchy process

We analyze energetics of a non-Gaussian process described by a stochastic differential equation of the Langevin type. The process represents a paradigmatic model of a nonequilibrium system subject to thermal fluctuations and additional external noise, with both sources of perturbations considered as additive and statistically independent forcings. We define thermodynamic quantities for trajectories of the process and analyze contributions to mechanical work and heat. As a working example we consider a particle subjected to a drag force and two independent Levy white noises with stability indices $\alpha=2$ and $\alpha=1$. The fluctuations of dissipated energy (heat) and distribution of work performed by the force acting on the system are addressed by examining contributions of Cauchy fluctuations to either bath or external force acting on the system

Fluctuation relations for anomalous dynamics generated by time-fractional Fokker-Planck equations

Anomalous dynamics characterized by non-Gaussian probability distributions (PDFs) and/or temporal long-range correlations can cause subtle modifications of conventional fluctuation relations. As prototypes we study three variants of a generic time-fractional Fokker-Planck equation with constant force. Type A generates superdiffusion, type B subdiffusion and type C both super- and subdiffusion depending on parameter variation. Furthermore type C obeys a fluctuation-dissipation relation whereas A and B do not. We calculate analytically the position PDFs for all three cases and explore numerically their strongly non-Gaussian shapes. While for type C we obtain the conventional transient work fluctuation relation, type A and type B both yield deviations by featuring a coefficient that depends on time and by a nonlinear dependence on the work. We discuss possible applications of these types of dynamics and fluctuation relations to experiments.Comment: 22 pages, 4 figure

Pilot study of the multicentre DISCHARGE trial: image quality and protocol adherence results of computed tomography and invasive coronary angiography (vol 30, pg 1997, 2020)

The original version of this article, published on 16 December 2019, unfortunately contained two mistakes.Cardiovascular Aspects of Radiolog

Breaking microscopic reversibility with Levy flights

A system at equilibrium exhibits microscopic reversibility, i.e. any path in phase space is just as often traversed in one direction as that it is traversed in the opposite direction. We show how it is justified to characterize white Gaussian noise as equilibrium noise: when an overdamped particle in a potential is subjected to such noise, microscopic reversibility can be proven for most-probable-paths that lead from one potential well to another. However, when the overdamped particle is subjected to white Levy noise, time-reversal symmetry is broken and microscopic reversibility is violated, even when the noise is symmetric. We, furthermore, derive how for an overdamped particle inside a parabolic potential microscopic reversibility is violated in the presence of Levy white noise. Similar to Brownian vortexes, Levy flights can be associated with the presence of Levy vortexes in phase space. Copyright (C) EPLA, 201

Cechy morfometryczne stop larw Dermacentor reticulatus [Fabricius, 1794] [Acari: Ixodida: Ixodidae] z populacji polskiej i slowackiej

Dermacentor reticulatus is widely distributed dangerous tick that usually lives in the river valleys, boggy forests, meadows, and wooded pastures. Tick populations from various regions may exhibit morphological differences. In our study we compared morphometric features of tarsus in larvae D. reticulatus from Polish and Slovakian populations. I tarsus width, III tarsus length, and length of dorsal setae of I tarsus were significantly higher in Polish populations. Indices of width to length of tarsus I and tarsus III were also significantly different in both populations. The other examined morphologic features were similar, what may result from the same environmental conditions of both populations