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Calculation of the magnetic field due to a bioelectric current dipole in an ellipsoid

Andrei Irimia (2008)

Applications of Mathematics

The bioelectric current dipole model is important both theoretically and computationally in the study of electrical activity in the brain and stomach due to the resemblance of the shape of these two organs to an ellipsoid. To calculate the magnetic field 𝐁 due to a dipole in an ellipsoid, one must evaluate truncated series expansions involving ellipsoidal harmonics 𝔼 n m , which are products of Lamé functions. In this article, we extend a strictly analytic model (G. Dassios and F. Kariotou, J. Math....

Cálculo de probabilidades en el análisis de perfiles genéticos compatibles.

Miguel Sánchez García, Pedro Cuesta Alvaro (2000)

Qüestiió

Un hecho delictivo ha sido cometido por una o más personas. Para descubrir el número de presuntos delincuentes, se determina el perfil genético de la evidencia forense encontrada en el lugar del delito, mediante el estudio de marcadores de tipo STR. En el presente artículo se desarrollan diversos algoritmos. En el primero se considera la probabilidad de que n personas elegidas aleatoriamente de la población de referencia contengan un perfil genético compatible, en el segundo se calcula la evidencia...

Cancer as Multifaceted Disease

A. Friedman (2012)

Mathematical Modelling of Natural Phenomena

Cancer has recently overtaken heart disease as the world’s biggest killer. Cancer is initiated by gene mutations that result in local proliferation of abnormal cells and their migration to other parts of the human body, a process called metastasis. The metastasized cancer cells then interfere with the normal functions of the body, eventually leading to death. There are two hundred types of cancer, classified by their point of origin. Most of them...

Canonical non-symmetrical correspondence analysis: an alternative in constrained ordination.

Priscila Willems, M. Purificación Galindo Villardon (2008)

SORT

Canonical non-symmetrical correspondence analysis is developed as an alternative method for constrained ordination, relating external information (e.g., environmental variables) with ecological data, considering species abundance as dependant on sites. Ordination axes are restricted to be linear combinations of the environmental variables, based on the information of the most abundant species. This extension and its associated unconstrained ordination method are terms of a global model that permits...

Cell Modelling of Hematopoiesis

N. Bessonov, L. Pujo-Menjouet, V. Volpert (2010)

Mathematical Modelling of Natural Phenomena

In this work, we introduce a new software created to study hematopoiesis at the cell population level with the individually based approach. It can be used as an interface between theoretical works on population dynamics and experimental observations. We show that this software can be useful to study some features of normal hematopoiesis as well as some blood diseases such as myelogenous leukemia. It is also possible to simulate cell communication and the formation of cell colonies in the bone marrow. ...

Cell-to-muscle homogenization. Application to a constitutive law for the myocardium

Denis Caillerie, Ayman Mourad, Annie Raoult (2003)

ESAIM: Mathematical Modelling and Numerical Analysis - Modélisation Mathématique et Analyse Numérique

We derive a constitutive law for the myocardium from the description of both the geometrical arrangement of cardiomyocytes and their individual mechanical behaviour. We model a set of cardiomyocytes by a quasiperiodic discrete lattice of elastic bars interacting by means of moments. We work in a large displacement framework and we use a discrete homogenization technique. The macroscopic constitutive law is obtained through the resolution of a nonlinear self-equilibrum system of the discrete lattice...

Cell-to-Muscle homogenization. Application to a constitutive law for the myocardium

Denis Caillerie, Ayman Mourad, Annie Raoult (2010)

ESAIM: Mathematical Modelling and Numerical Analysis

We derive a constitutive law for the myocardium from the description of both the geometrical arrangement of cardiomyocytes and their individual mechanical behaviour. We model a set of cardiomyocytes by a quasiperiodic discrete lattice of elastic bars interacting by means of moments. We work in a large displacement framework and we use a discrete homogenization technique. The macroscopic constitutive law is obtained through the resolution of a nonlinear self-equilibrum system of the discrete lattice...

Centrosymmetric Graphs And A Lower Bound For Graph Energy Of Fullerenes

Gyula Y. Katona, Morteza Faghani, Ali Reza Ashrafi (2014)

Discussiones Mathematicae Graph Theory

The energy of a molecular graph G is defined as the summation of the absolute values of the eigenvalues of adjacency matrix of a graph G. In this paper, an infinite class of fullerene graphs with 10n vertices, n ≥ 2, is considered. By proving centrosymmetricity of the adjacency matrix of these fullerene graphs, a lower bound for its energy is given. Our method is general and can be extended to other class of fullerene graphs.

Cerebral blood flow simulations in realistic geometries

Stéphanie Salmon, Soyibou Sy, Marcela Szopos (2012)

ESAIM: Proceedings

The aim of this work is to perform the computation of the blood flow in all the cerebral network, obtained from medical images as angiographies. We use free finite elements codes as FreeFEM++. We first test the code on analytical solutions in simplified geometries. Then, we study the influence of boundary conditions on the flow and we finally perform first computations on realistic meshes.

Characterization of lung tumor subtypes through gene expression cluster validity assessment

Giorgio Valentini, Francesca Ruffino (2006)

RAIRO - Theoretical Informatics and Applications

The problem of assessing the reliability of clusters patients identified by clustering algorithms is crucial to estimate the significance of subclasses of diseases detectable at bio-molecular level, and more in general to support bio-medical discovery of patterns in gene expression data. In this paper we present an experimental analysis of the reliability of clusters discovered in lung tumor patients using DNA microarray data. In particular we investigate if subclasses of lung adenocarcinoma...

Chemotaxis models with a threshold cell density

Dariusz Wrzosek (2008)

Banach Center Publications

We consider a quasilinear parabolic system which has the structure of Patlak-Keller-Segel model of chemotaxis and contains a class of models with degenerate diffusion. A cell population is described in terms of volume fraction or density. In the latter case, it is assumed that there is a threshold value which the density of cells cannot exceed. Existence and uniqueness of solutions to the corresponding initial-boundary value problem and existence of space inhomogeneous stationary solutions are discussed....

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