Saturday April 13, 2013, 8:30 a.m.-10:50 a.m.
Special Session on Algebras, Lattices and Varieties, I
Room 255, Hellems Arts and Sciences
Organizers:
Keith A. Kearnes, University of Colorado, Boulder kearnes@euclid.colorado.edu
Ágnes Szendrei, University of Colorado, Boulder
- 8:30 a.m.
  Every Finite Lattice is Finitely Based.
  George F McNulty*, University of South Carolina
  (1089-08-396)
- 9:00 a.m.
  The Undecidability of the Definability of Principal Subcongruences. Slides.
  Matthew D Moore*, The University of Colorado at Boulder
  (1089-08-388)
- 9:30 a.m.
  Finitely decidable varieties admitting type 1 are residually finite. Slides.
  Ralph McKenzie, Vanderbilt University
  Matthew Smedberg*, Vanderbilt University
  (1089-08-27)
- 10:00 a.m.
  A general Dedekind transposition principle and examples of isotopic algebras with non-isomorphic congruence lattices. Slides. Some photos.
  William DeMeo*, University of South Carolina
  (1089-06-320)
- 10:30 a.m.
  Finite lattices that force transitivity of G-Set representations. Slides.
  Steve Seif*, Mathematics Department, University of Louisville
  (1089-08-354)

Saturday April 13, 2013, 3:00 p.m.-5:20 p.m.
Special Session on Algebras, Lattices and Varieties, II
Room 255, Hellems Arts and Sciences
Organizers:
Keith A. Kearnes, University of Colorado, Boulder kearnes@euclid.colorado.edu
Ágnes Szendrei, University of Colorado, Boulder
- 3:00 p.m.
  Varieties of Lattice-Ordered Groups and Unital Lattice-Ordered Groups. Slides.
  W. Charles Holland*, University of Colorado
  (1089-06-95)
- 3:30 p.m.
  Involutive residuated lattices based on modular and distributive lattices.
  Jeffrey S. Olson*, Norwich University
  (1089-06-17)
- 4:00 p.m.
  Distributive integral residuated lattices have the FEP. Slides.
  Nikolaos Galatos*, University of Denver
  (1089-06-326)
- 4:30 p.m.
  Varieties of generalized hoops and integral GBL-algebras. Slides.
  Peter Jipsen*, Chapman University
  (1089-06-381)
- 5:00 p.m.
  Automorphisms of Decompositions. Slides.
  Tim Hannan, New Mexico State University
  John Harding*, New Mexico State University
  (1089-06-114)

Sunday April 14, 2013, 8:30 a.m.-10:50 a.m.
Special Session on Algebras, Lattices and Varieties, III
Room 255, Hellems Arts and Sciences
Organizers:
Keith A. Kearnes, University of Colorado, Boulder kearnes@euclid.colorado.edu
Ágnes Szendrei, University of Colorado, Boulder
- 8:30 a.m.
  Bipartite graphs and their idempotent polymorphisms. Slides.
  Ross Willard*, University of Waterloo
  (1089-05-284)
- 9:00 a.m.
  Graphs, digraphs and k-NU polymorphisms. Slides.
  Tomas Feder, Stanford University
  Pavol Hell, Simon Fraser University
  Benoit Larose*, Concordia University
  Mark Siggers, Kyungpook National University
  Claude Tardif, Royal Military College, Kingston
  (1089-08-97)
- 9:30 a.m.
  CSP for Commutative, Idempotent Groupoids. Slides.
  Clifford Bergman, Iowa State University
  David Failing*, Iowa State University
  (1089-08-43)
- 10:00 a.m.
  Algebraic closure of some generalized convex sets. Slides.
  Anna B. Romanowska*, Warsaw University of Technology, Mathematics and Information Science
  Gabor Czedli, University of Szeged, Hungary
  (1089-08-233)
- 10:30 a.m.
  Malcev families of quasivarieties closed under join or Malcev product.
  Ralph N McKenzie*, Vanderbilt University
  (1089-08-405)

Sunday April 14, 2013, 3:00 p.m.-4:50 p.m.
Special Session on Algebras, Lattices and Varieties, IV
Room 255, Hellems Arts and Sciences
Organizers:
Keith A. Kearnes, University of Colorado, Boulder kearnes@euclid.colorado.edu
Ágnes Szendrei, University of Colorado, Boulder
- 3:00 p.m.
  Congruence n-permutable varieties. Slides.
  Matt Valeriote*, McMaster University
  (1089-08-274)
- 3:30 p.m.
  A disjunction characterizing varieties with a weak difference term. Slides.
  Alexander Wires*, Vanderbilt University
  (1089-08-350)
- 4:00 p.m.
  Directional algebras and digroups.
  Jonathan D.H. Smith*, Iowa State University
  (1089-08-218)
- 4:30 p.m.
  Topological algebras on finite simplicial complexes. Slides.
  Walter Taylor*, University of Colorado, Boulder, Colorado
  (1089-08-136)