It is with great sadness that we announce the passing of Professor Stefan H. Mackiewicz on September 28, 2017. Professor Stefan Mackiewicz was an outstanding Polish rheumatologist. He was a graduate of the Medical University of Poznan. After graduation he worked at the Third Department of Internal Medicine in Poznan. In 1967 he became the Chairman of the Department of Rheumatology and Immunolog...

We develop and analyse a discrete, one-dimensional model of cell motility which incorporates the effects of volume filling, cell-to-cell adhesion and chemotaxis. The formal continuum limit of the model is a nonlinear generalisation of the parabolic-elliptic Keller-Segel equations, with a diffusivity which can become negative if the adhesion coefficient is large. The consequent ill-posedness res...

In this paper, a multi-scale analysis scheme for solidification based on two-scale computational homogenization is discussed. Solidification problems involve evolution of surfaces coupled with flux jump boundary conditions across interfaces. We provide consistent macro-micro transition and averaging rules based on Hill’s macrohomogeneity condition. The overall macro-scale behavior is analyzed w...

We consider a stochastic perturbation of the Stefan problem. The noise is Brownian in time and smoothly correlated in space. We prove existence and uniqueness and characterize the domain of existence.

a Jožef Stefan Institute, Department of Knowledge Technologies, Jamova cesta 39, 1000 Ljubljana, Slovenia b Jožef Stefan International Postgraduate School, Jamova 39, 1000 Ljubljana, Slovenia c Dipartimento di Informatica, Università degli Studi di Bari “Aldo Moro”, via Orabona 4, 70125 Bari, Italy d Centre of Excellence for Integrated Approaches in Chemistry and Biology of Proteins, Jamova 39,...

The one-phase reduction of the Stefan problem, where the phase change temperature is a variable, is analysed. It is shown that problems encountered in previous analyses may be traced back to an incorrectly formulated Stefan condition. Energy conserving reductions for Cartesian, cylindrically and spherically symmetric problems are presented and compared with solutions to the two-phase problem.

When attacked by predators, flatfishes perform fast-starts that result in a rapid take-off from the ocean bottom on which they lie. High-speed video recordings of the blind side of flatfishes indicate that they expel a coherent jet of water from the blind-side opercular valve during take-off. Buccal pressure recordings in winter flounder (Pseudopleuronectes americanus) show that a buccal pressu...

An approximation procedure for the identiication of a nonlinear boundary heat transfer function in a one phase Stefan problem is presented. Alternatively the problem can be viewed as constructing a feedback control law for the control of the solidiication surface in the Stefan problem. The analysis is based on Hilbert space methods and convex analysis techniques. Numerical results combining two...