On closed currents invariant by holomorphic foliations, I

We consider closed positive currents invariant by a singular holomorphic foliation on an algebraic surface. We show that under some conditions the foliation must leave invariant an algebraic curve

Discrete orbits, recurrence and solvable subgroups of Diff(C^2,0)

We discuss the local dynamics of a subgroup of Diff(C^2,0) possessing locally discrete orbits as well as the structure of the recurrent set for more general groups. It is proved, in particular, that a subgroup of Diff(C^2,0) possessing locally discrete orbits must be virtually solvable. These results are of considerable interest in problems concerning integrable systems.Comment: The first version of this paper and "A note on integrability and finite orbits for subgroups of Diff(C^n,0)" are an expanded version of our paper "Discrete orbits and special subgroups of Diff(C^n,0)". An intermediate version re-submitted to the journal on March 2015 is available at http://www.fep.up.pt/docentes/hreis/publications.htm where there is also a comparison between these 3 version

Investment Prices and Exchange Rates: Some Basic Facts

This paper documents four basic facts about investment goods and investment prices. First, investment has a very significant nontradable component in the form of construction services. Second, distributions services (wholesaling, retailing, and transportation) are much less important for investment than for consumption. Third, the import content of investment is much larger than that of consumption. Finally, in the aftermath of three large devaluations, the rate of exchange rate pass-through is, perhaps not surprisingly, highest for imported equipment and lowest for construction services.