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Analysis of Space-Temporal Symmetry in the Early Embryogenesis of Calla palustris L., Araceae

I.V. Rudskiy, G.E. Titova, T.B. Batygina (2010)

Mathematical Modelling of Natural Phenomena

Plants and animals have highly ordered structure both in time and in space, and one of the main questions of modern developmental biology is the transformation of genetic information into the regular structure of organism. Any multicellular plant begins its development from the universal unicellular state and acquire own species-specific structure in the course of cell divisions, cell growth and death, according to own developmental program. However the cellular mechanisms of plant development are...

Analyzing sets of phylogenetic trees using metrics

Damian Bogdanowicz (2011)

Applicationes Mathematicae

The reconstruction of evolutionary trees is one of the primary objectives in phylogenetics. Such a tree represents historical evolutionary relationships between different species or organisms. Tree comparisons are used for multiple purposes, from unveiling the history of species to deciphering evolutionary associations among organisms and geographical areas. In this paper, we describe a general method for comparing phylogenetic trees and give some basic properties of the Matching Split metric, which...

Analyzing the dynamics of deterministic systems from a hypergraph theoretical point of view

Luis M. Torres, Annegret K. Wagler (2013)

RAIRO - Operations Research - Recherche Opérationnelle

To model the dynamics of discrete deterministic systems, we extend the Petri nets framework by a priority relation between conflicting transitions, which is encoded by orienting the edges of a transition conflict graph. The aim of this paper is to gain some insight into the structure of this conflict graph and to characterize a class of suitable orientations by an analysis in the context of hypergraph theory.

Antichains in the homomorphism order of graphs

Dwight Duffus, Peter, L. Erdös, Jaroslav Nešetřil, Lajos Soukup (2007)

Commentationes Mathematicae Universitatis Carolinae

Let 𝔾 and 𝔻 , respectively, denote the partially ordered sets of homomorphism classes of finite undirected and directed graphs, respectively, both ordered by the homomorphism relation. Order theoretic properties of both have been studied extensively, and have interesting connections to familiar graph properties and parameters. In particular, the notion of a duality is closely related to the idea of splitting a maximal antichain. We construct both splitting and non-splitting infinite maximal antichains...

Antidomatic number of a graph

Bohdan Zelinka (1997)

Archivum Mathematicum

A subset D of the vertex set V ( G ) of a graph G is called dominating in G , if for each x V ( G ) - D there exists y D adjacent to x . An antidomatic partition of G is a partition of V ( G ) , none of whose classes is a dominating set in G . The minimum number of classes of an antidomatic partition of G is the number d ¯ ( G ) of G . Its properties are studied.

Antiflows, oriented and strong oriented colorings of graphs

Robert Šámal (2004)

Archivum Mathematicum

We present an overview of the theory of nowhere zero flows, in particular the duality of flows and colorings, and the extension to antiflows and strong oriented colorings. As the main result, we find the asymptotic relation between oriented and strong oriented chromatic number.

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