Results 271 to 280 of about 455,903 (307)

The Molecular Graphs

1989
The purpose of this chapter is to present basic concepts of graph theory [1] as applied to organic chemistry [2–6]. The importance of graph theory in this large branch of chemistry consists in the existence of the phenomena of the structural formula and its isomerism.
J. Koča, M. Kratochvíl, L. Matyska, V. Kvasnička, J. Pospíchal   +4 more
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On the Complexity of Molecular Graphs

MATCH : communications in mathematical and in computer chemistry, 1999
On the Complexity of Molecular ...
Nikolić, Sonja, Trinajstić, Nenad, Tolić, Iva Marija   +2 more
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On the centrality of vertices of molecular graphs

Journal of Computational Chemistry, 2013
For acyclic systems the center of a graph has been known to be either a single vertex of two adjacent vertices, that is, an edge. It has not been quite clear how to extend the concept of graph center to polycyclic systems. Several approaches to the graph center of molecular graphs of polycyclic graphs have been proposed in the literature. In most cases
Milan Randic, Marjana Novic, Marjan Vracko, Dejan Plavsic   +3 more
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Graphs for Core Molecular Biology

2003
A graphic language--the graphic ? calculus--modeling protein interactions at the domain level is introduced. Complexation, activation and mixed forms of interaction are expressed as graph rewriting rules. A compilation in a low-level graph rewriting calculus, called mobile ?, is given and shown to be correct up to some suitable notion of observational ...
Vincent Danos, Cosimo Laneve
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Graph Databases in Molecular Biology

2018
In recent years, the increase in the amount of data generated in basic social practices and specifically in all fields of research has boosted the rise of new database models, many of which have been employed in the field of Molecular Biology. NoSQL graph databases have been used in many types of research with biological data, especially in cases where
Waldeyr Mendes Cordeiro da Silva, Polyane Wercelens, Maria Emília M. T. Walter, Maristela Holanda, Marcelo M. Brigido   +4 more
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Topological Indices Based on the Line Graph of the Molecular Graph

Journal of Chemical Information and Computer Sciences, 1996
The topological index e recently proposed by one of the authors [E. Estrada, J. Chem. Inf. Comput. Sci. 1995, 35, 31−33] is shown to be identical to the connectivity index of the line graph of the molecular graph. This observation makes it possible to conceive a whole class of novel, line-graph-based topological indices.
Ivan Gutman, Ernesto Estrada
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Graph-Based Molecular Alignment (GMA)

Journal of Chemical Information and Modeling, 2007
We describe a combined 2D/3D approach for the superposition of flexible chemical structures, which is based on recent progress in the efficient identification of common subgraphs and a gradient-based torsion space optimization algorithm. The simplicity of the approach is reflected in its generality and computational efficiency: the suggested approach ...
Jörn Marialke, Robert Körner, Simon Tietze, Joannis Apostolakis   +3 more
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Graphs in Molecular Epidemiology

2021
AbstractGraphs and networks are used in molecular epidemiology to model the evolution of viruses and their spread during outbreaks and epidemics. They are instrumental at different stages of the computational pipelines. This includes the inference of transmission networks using viral sequences sampled from infected individuals, and studies of selection
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Graph Valence Shells as Molecular Descriptors

Journal of Chemical Information and Computer Sciences, 2001
We have introduced a new simple structural descriptor for molecules that is based on the count of the valence shells for vertices in molecular graphs. The construction of the new descriptor is illustrated on 2,3-dimethylhexane and is reported for the 18 octane isomers.
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Novel Shape Descriptors for Molecular Graphs

Journal of Chemical Information and Computer Sciences, 2001
We report on novel graph theoretical indices which are sensitive to the shapes of molecular graphs. In contrast to the Kier's kappa shape indices which were based on a comparison of a molecular graph with graphs representing the extreme shapes, the linear graph and the "star" graph, the new shape indices are obtained by considering for all atoms the ...
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