Foliated vector fields without periodic orbits
  In this article parametric versions of Wilson's plug and Kuperberg's plug are discussed. We show that there is a weak homotopy equivalence induced by the inclusion between the space of non-singular vector fields tangent to a foliation and the subspace of those without closed orbits, as long as the leaves of the foliation have dimension at least 3. We contrast this with the case of foliations by surfaces in 3-manifolds. 
Daniel Peralta-Salas, Alvaro del Pino, Francisco Presas
math.DS math.DG