Given an improper action (= cell stabilizers are innnite) of a group G on a CW-complex X , we present criteria, based on connectivity at innnity properties of the cell stabilizers under the action of G that imply connectivity at innnity properties for G. A reenement of this idea yields information on the topology at innnity of Artin groups, and it gives signiicant progress on the question of wh...

In papers by Semmes [6], Macpherson and Neumann [4] and Brazil, Covington, Penttila, Praeger and Woods [2], it has been shown that stabilizers of filters (equivalently, stabilizers of ideals) play a crucial role in the study of maximal subgroups of infinite symmetric groups. Semmes proved that if if is a maximal subgroup of S = Sym (Q), where Q is a set of infinite cardinality K and H contains ...

Should the generosity of unemployment benefits and the progressivity of income taxes depend on the presence of business cycles? This paper proposes a tractable model where there is a role for social insurance against uninsurable shocks to income and unemployment, as well as inefficient business cycles driven by aggregate shocks through matching frictions and nominal rigidities. We derive an aug...

OBJECTIVE To review studies on treatments for bipolar depression and make recommendations for practising clinicians treating patients with bipolar depression. METHOD Studies that examined various treatments for bipolar depression were evaluated and rated for evidence of efficacy using Periodic Health Examination criteria. The rating for classification of recommendation for an intervention was...