On the controllability of the 2-D Vlasov-Stokes system

In this paper we prove an exact controllability result for the Vlasov-Stokes system in the two-dimensional torus with small data by means of an internal control. We show that one can steer, in arbitrarily small time, any initial datum of class C 1 satisfying a smallness condition in certain weighted spaces to any final state satisfying the same conditions. The proof of the main result is achieved thanks to the return method and a Leray-Schauder fixed-point argument

Synchronizing weighted automata

We introduce two generalizations of synchronizability to automata with transitions weighted in an arbitrary semiring K=(K,+,*,0,1). (or equivalently, to finite sets of matrices in K^nxn.) Let us call a matrix A location-synchronizing if there exists a column in A consisting of nonzero entries such that all the other columns of A are filled by zeros. If additionally all the entries of this designated column are the same, we call A synchronizing. Note that these notions coincide for stochastic matrices and also in the Boolean semiring. A set M of matrices in K^nxn is called (location-)synchronizing if M generates a matrix subsemigroup containing a (location-)synchronizing matrix. The K-(location-)synchronizability problem is the following: given a finite set M of nxn matrices with entries in K, is it (location-)synchronizing? Both problems are PSPACE-hard for any nontrivial semiring. We give sufficient conditions for the semiring K when the problems are PSPACE-complete and show several undecidability results as well, e.g. synchronizability is undecidable if 1 has infinite order in (K,+,0) or when the free semigroup on two generators can be embedded into (K,*,1).Comment: In Proceedings AFL 2014, arXiv:1405.527

Synthesis of the Macrocylic Core of the Solomonamides, a New Class of Cyclopeptides of Marine Origin

Se describe estudios sintéticos dirigidos hacia la síntesis total de solomonamides, una nueva clase de ciclopéptidos de origen marino que presentan interesantes propiedades biológicas. La aproximación sintética se basó en la metátesis de cierre de anillo como vía para formar el sistema macrocíclico de forma rápida y eficaz.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech