Parks, Peace and Partnership: Global Initiatives in Transboundary Conservation Edited by Michael S. Quinn, Len Broberg, and Wayne Freimund

Review of Parks, Peace and Partnership: Global Initiatives in Transboundary Conservation edited by Michael S. Quinn, Len Broberg, and Wayne Freimund

Some effects of copper contaminated pig slurry on earthworms

Not availabl

Weyl Algebras and Knots

In this paper we push forward results on the invariant ${\cal F}$-module of a virtual knot investigated by the first named author where ${\cal F}$ is the algebra with two invertible generators $A,B$ and one relation $A^{-1}B^{-1}AB-B^{-1}AB= BA^{-1}B^{-1}A-A$. For flat knots and links the two sides of the relation equation are put equal to unity and the algebra becomes the Weyl algebra. If this is perturbed and the two sides of the relation equation are put equal to a general element, $q$, of the ground ring, then the resulting module lays claim to be the correct generalization of the Alexander module. Many finite dimensional representations are given together with calculations.Comment: 18 pages, 5 figures, accepted by Journal of Geometry and Physic

Structural change in cigarette demand: cusum tests using panel data

We conduct cusum tests of structural change in a rational addiction model of cigarette demand estimated using a panel of annual time series of state-level data. In contrast to the one previous application of cusum tests to the question of cigarette demand stability, our results provide strong evidence of downward shifts in demand during the modern era of health warnings and anti-smoking campaigns.