Agents that modulate cardiac and smooth muscle K+ channels have stimulated considerable interest in recent years because of their therapeutic potential in a number of cardiovascular diseases. Foremost among these drugs are the so-called Class III antiarrhythmic agents, which act by prolonging cardiac action potentials, and K+ channel openers, which hyperpolarize and thereby relax smooth muscle ...

In this article we consider sheaf quotients of affine superschemes by finite supergroups that act on them freely. More precisely, if a finite supergroup G acts on an affine superscheme X freely, then the quotient K-sheaf ̃ X/G is again an affine superscheme Y , where K[Y ] ≃ K[X ]. Besides, K[X ] is a finitely presented projective K[X ]-module.

Let Fn be the free group on n generators. Define IAn to be group of automorphisms of Fn that act trivially on first homology. The Johnson homomorphism in this setting is a map from IAn to its abelianization. The first goal of this paper is to determine how much this map contributes to the second rational cohomology of IAn . A descending central series of IAn is given by the subgroups K (i) n wh...

in this paper firt of all we introduce a generalization of torsion freeness of acts over monoids, called -torsion freeness. then in section 1 of results we give some general properties and in sections 2, 3 and 4 we give a characterization of monoids for which this property of their right rees factor, cyclic and acts in general  implies some other properties, respectively.