23 documents found, page 1 of 3
Equilibrium of a kinetic model of oscillating patterns for chronic autoimmune d...
Oliveira, João Miguel; Ramos, M. P. Machado; Ribeiro, Carolina; Soares, A. J.We study the equilibrium states of a non-linear kinetic system of integro-partial differential equations describing the well known relapsing-remitting stages observed in many chronic autoimmune diseases. The kinetic system describes the immune system at the cellular level in terms of conservative, proliferative and destructive interactions between population of cells, with the addition of natural death rates an...
Stimulating critical thinking through report peer-review in a project-based lea...
Alves, Anabela Carvalho; Leão, Celina Pinto; Abreu, Maria Florentina Queirós Silva; Pimentel, Carina Maria Oliveira; Malheiro, M. TeresaProject-based learning (PBL) is an active learning methodology proposed in the early 20th century. Nevertheless, it continues to be a very suitable methodology for the current generation of students. Probably, it is more relevant now than before, since recent generations are more motivated by these learning methodologies. This is due to the fact that today’s students are totally absorbed by technologies that, i...
Mathematical modelling of oscillating patterns for chronic autoimmune diseases
Della Marca, Rossella; Ramos, M. P. Machado; Ribeiro, Carolina; Soares, A. J.Many autoimmune diseases are chronic in nature, so that in general patients experience periods of recurrence and remission of the symptoms characterizing their specific autoimmune ailment. In order to describe this very important feature of autoimmunity, we construct a mathematical model of kinetic type describing the immune system cellular interactions in the context of autoimmunity exhibiting recurrent dynami...
Rarefied relativistic polyatomic gases in a gravitational field
Oliveira, J. M. S.; Soares, A. J.; Ramos, M. P. MachadoThe principal goal of the present paper is to study rarefied relativistic polyatomic gases in both Minkowski spacetime and Robertson-Walker spacetime. The field equations are determined from a recently developed generalized relativistic BGK-type model for polyatomic gases. This model is applied to both Minkowski spacetime and at and non at Robertson-Walker spacetimes. The equation of state for the non-equilibri...
Kinetic modelling of autoimmune diseases
Ramos, M. P. Machado; Ribeiro, Carolina; Soares, A. J.In this paper, we review previous results obtained by the authors, concerning the mathematical modelling of autoimmune diseases when the kinetic theory approach is used in order to describe the microscopic interactions between cells. Three cell populations are considered and the distribution function of each population depends on the biological activity variable defining the functional state relevant for that p...
Recent developments on the modelling of cell interactions in autoimmune diseases
Costa, M. Fernanda P.; Ramos, M. P. Machado; Ribeiro, Carolina; Soares, A. J.In this paper, we give an overview of our recent results concerning the mathematical modelling of autoimmune diseases in absence [1] and in presence [2] of immunotherapeutic treatment. Then we complement the model description given in [2], by developing here a kinetic system describing the cellular dynamics corresponding to the macroscopic model presented in [2]. This is the main new contribution in these proce...
Optimal control model of immunotherapy for autoimmune diseases
Costa, M. Fernanda P.; Ramos, M. P. Machado; Ribeiro, Carolina; Soares, A. J.In this work, we develop a new mathematical model to evaluate the impact of drug therapies on autoimmunity disease. We describe the immune system interactions at the cellular level, using the kinetic theory approach, by considering self-antigen presenting cells, self-reactive T cells, immunosuppressive cells and Interleukin-2 (IL-2) cytokines. The drug therapy consists of an intake of Interleukin-2 cytokines wh...
A kinetic model of T cell autoreactivity in autoimmune diseases
Ramos, M. P. Machado; Ribeiro, Carolina; Soares, A. J.We construct a mathematical model of kinetic type in order to describe the immune system interactions in the context of autoimmune disease. The interacting populations are self-antigen presenting cells, self-reactive T cells and the set of immunosuppressive cells consisting of regulatory T cells and NaturalKiller cells. The main aim of our work is to develop a qualitative analysis of the model equations and inv...
Conformally flat metrics with anisotropic pressure
Brito, Irene; Ramos, M. P. MachadoA particular class of conformally flat spacetimes possessing isotropic and anisotropic pressure are investigated, using 1+3 formalism. We specialize the 1+3 equations obtained for the respective class of spacetimes to a compatible and simple equation of state where the energy per particle depends only on the particle density and the shear scalar.
Elasticidade relativista
Ramos, M. P. Machado[Excerto] A teoria clássica Newtoniana da elasticidade, que estuda a deformação de corpos sólidos quando estes sofrem a Acão de forcas, foi estabelecida no seculo XVII. Contudo, o desenvolvimento de uma teoria da elasticidade no contexto da Relatividade Geral foi feito muito mais tarde. Em meados do seculo XX, no contexto do detetor de Weber (1) para a deteção de ondas gravitacionais, foi necessário explicar co...