A digraph embedded on a torus can be flattened out into the plane to form a 2-dimensional partially ordered set (poset) by cutting a pair of orthogonal fundamental cycles. The family of 2-dimensional posets arising from a single toric digraph is called the web of the digraph. In 1994 Halitsky noted that tree families important in linguistics had additional symmetry if embedded on a torus and then transformed into another member of the web. Halitsky has attempted to use this “hidden symmetry” idea to predict tertiary structure of proteins from their primary structure.


Tertiary Structure Directed Path Graph Transformation Directed Cycle Directed Walk 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2004

Authors and Affiliations

  • Robert E. Jamison
    • 1
  1. 1.Department of Mathematical SciencesClemson UniversityClemsonUSA

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