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Problems with classical models of sex-ratio evolution

Krzysztof Argasiński (2008)

Banach Center Publications

The classical theory of the sex-ratio evolution, known as the sex-ratio game, is based on the maximization of the number of grandchildren, treated as a fitness measure of a female producing offspring of the sex ratio that is coded in her genes. The theory predicts that it is more profitable to produce offspring with less numerous sex. We can find in the literature mutually exclusive conclusions based on this prediction: some textbooks say that populations with the equal number of sons and daughters...

Progress in developing Poisson-Boltzmann equation solvers

Chuan Li, Lin Li, Marharyta Petukh, Emil Alexov (2013)

Molecular Based Mathematical Biology

This review outlines the recent progress made in developing more accurate and efficient solutions to model electrostatics in systems comprised of bio-macromolecules and nanoobjects, the last one referring to objects that do not have biological function themselves but nowadays are frequently used in biophysical and medical approaches in conjunction with bio-macromolecules. The problem of modeling macromolecular electrostatics is reviewed from two different angles: as a mathematical task provided...

Propagation of elastic waves in DNA.

Mukherjee, Sunil, Sarkar, Saumyendra Nath, Raychaudhuri, Probhas, Mazumdar, Sunil Kumar (1983)

International Journal of Mathematics and Mathematical Sciences

Propagation of Growth Uncertainty in a Physiologically Structured Population

H.T. Banks, S. Hu (2012)

Mathematical Modelling of Natural Phenomena

In this review paper we consider physiologically structured population models that have been widely studied and employed in the literature to model the dynamics of a wide variety of populations. However in a number of cases these have been found inadequate to describe some phenomena arising in certain real-world applications such as dispersion in the structure variables due to growth uncertainty/variability. Prompted by this, we described two recent...

Properties of a singular value decomposition based dynamical model of gene expression data

Krzysztof Simek (2003)

International Journal of Applied Mathematics and Computer Science

Recently, data on multiple gene expression at sequential time points were analyzed using the Singular Value Decomposition (SVD) as a means to capture dominant trends, called characteristic modes, followed by the fitting of a linear discrete-time dynamical system in which the expression values at a given time point are linear combinations of the values at a previous time point. We attempt to address several aspects of the method. To obtain the model, we formulate a nonlinear optimization problem...

Protector control: Extension to a class of nonlinear distributed systems

Youssef Qaraai, Abdes Samed Bernoussi (2010)

International Journal of Applied Mathematics and Computer Science

We present an extension of the protector control scheme introduced for the linear case in a previous work to a class of nonlinear systems. The systems considered are assumed to have a finite propagation velocity while the initial state is subject to a spreading disturbance. We characterize such a control first by using the remediability approach to the resulting nonlinear delay system, and then by coupling families of transformations and the delay approach. To illustrate this work, we provide a...

Quality improvement of rule-based gene group descriptions using information about GO terms importance occurring in premises of determined rules

Marek Sikora, Aleksandra Gruca (2010)

International Journal of Applied Mathematics and Computer Science

In this paper we present a method for evaluating the importance of GO terms which compose multi-attribute rules. The rules are generated for the purpose of biological interpretation of gene groups. Each multi-attribute rule is a combination of GO terms and, based on relationships among them, one can obtain a functional description of gene groups. We present a method which allows evaluating the influence of a given GO term on the quality of a rule and the quality of a whole set of rules. For each...

Quantifying the Impact of Bacterial Fitness and Repeated Antimicrobial Exposure on the Emergence of Multidrug-Resistant Gram-Negative Bacilli

E. M.C. D'Agata, M. Horn, G. Webb (2010)

Mathematical Modelling of Natural Phenomena

The emergence of multidrug resistance among gram-negative bacilli is complex. Numerous factors need to be considered, including the biological fitness cost of resistance, fitnesscompensatory mutations and frequency and type of antibiotic exposure. A mathematical model evaluating these complex relationships was developed in an individual colonized with strains of pan-susceptible, single-, two- and multidrug-resistant (MDR) gram-negative bacilli (GN). The effect of bacterial fitness, compensatory...

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