Response to ``Comment on `Primordial magnetic seed field amplification by gravitational waves' "

Here we respond to the comment by Tsagas (gr-qc/0503042) on our paper gr-qc/0503006. We show that the results in that comment are flawed and cannot be used for drawing conclusion about the nature of magnetic field amplification by gravitational waves, and give further support that the results of gr-qc/0503006 are correct.Comment: 4 pages, 2 figures, to appear in Physical Review

Double martingale structure and existence of φ-moments for weighted branching processes

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Covid-19 and Post Intensive Care Syndrome: A Call for Action

Although we are currently overwhelmed by the astonishing speed of infection of the Covid-19 pandemic, and the daily onslaught of new, and ever-worsening predictions, it is vital that we begin to prepare for the aftershocks of the pandemic. Prominent among this will be the cohort of post-intensive case survivors who have been mechanically ventilated and will like experience short- and medium-term consequences of the experience. The notion that patients surviving intensive care and mechanical ventilation for several weeks can be discharged home without further medical attention is a dangerous illusion. Post Intensive Care Syndrome and other severe conditions will require not only adequate screening but early rehabilitation and other interventions. Action must be taken now to prepare for this inevitable shock to the healthcare system

Weak coupling approximations in non-Markovian Transport

We study the transport properties of the Fano-Anderson model with a Lorentzian-shaped density of states in one of the electronic reservoirs. We explicitly show that the energy dependence of the density of states can cause non-Markovian effects and that the non-Markovian master equation may fail if these effects are strong. We evaluate the stationary current, the zero frequency current noise and the occupation dynamics of the resonant level by means of a quantum master equation approach within different approximation schemes and compare the results to the exact solution obtained by scattering theory and Green's functions.Comment: 9 pages, 6 figures; due to suggestions of a referee we have added an appendix where our kernel is derived in detail; a few typos are correcte

The Nonlinear Dynamic Conversion of Analog Signals into Excitation Patterns

Local periodic perturbations induce frequency-dependent propagation waves in an excitable spatio-temporally chaotic system. We show how segments of noise-contaminated and chaotic perturbations induce characteristic sequences of excitations in the model system. Using a set of tuned excitable systems, it is possible to characterize signals by their spectral composition of excitation pattern. As an example we analyze an epileptic spike-and-wave time series.Comment: 14 pages, 5 figure