The article deals with interaction of tumour cells and leucocytes in the cylindrical cavities. This type of interaction is typical in the cases of development of a tumour in the intestine, blood vessel or in a bone cavity. Two cases are separated: the case of soft and hard tumour. In the case of a solid tumour, leucocytes can interact only with the surface cells of the tumour. This type of interaction is described by the system of two nonlinear first degree differential equations. The expressions of stationary points are obtained and analysis of their stability is performed. In the case of a soft tumour the system of two partial differential equations with first order derivatives and initial and boundary conditions is proposed. An algorithm for computing the numeric solution of the mathematical model is applied. In this case the diffusion of leucocytes and their ability to reach the tumour cells in the whole volume of the tumour is included. The algorithm is constructed and the system is solved numerically. Bifurcation curve is obtained. It separates two qualitatively different areas on the two parameter plane. Under the same initial parameters in the first area development of the tumour cells cannot be stopped, whereas in the second area leukocytes defeat the tumour cells.
Journal:Acta Historica Universitatis Klaipedensis
Volume 25 (2012): Klaipėdos krašto konfesinis paveldas: tarpdisciplininiai senųjų kapinių tyrimai = Confessional Heritage of Klaipėda Region: Interdisciplinary Research into the Old Cemeteries, pp. 89–122
Abstract
The epigraphs of the Evangelical Lutheran cemeteries of Klaipėda provide rich information. They present exhaustive data on the buried person: full dates of their births and deaths, names, surnames, and maiden names of married women; sometimes even the place of origin or the social-professional status is indicated. Beside the personal data, the epigraphs contain farewell or sacred texts addressed to the dead. The ethnic Evangelical Lutheran cemeteries in Klaipėda Region significantly suffered during the historical and political events unfavourable for them. The majority of tombstones and crosses were totally destroyed and cannot be reconstructed. Unique information about the population of the Region was lost forever. In the article, the author analyzes the data presented in epigraphs: the distribution of the dead by gender and age, high infant/ children mortality rates, and other.