The homoclinic and heteroclinic structure in dynamical systems was first used to produce C-algebras in the way breaking work of Cuntz and Krieger in [Kr1], [Kr2] and [CuK]. This work has been generalized in many directions where the relation to dynamical systems is either absent or appears very implicit, but Ian Putnam described in [Pu] a natural way to extend the constructions of Cuntz and Kri...

This paper reports the results of a zooarchaeological analysis conducted on the occupation layer of a compound structure (Residential Unit 1) of the Pucara de Tilcara archaeological site (Jujuy Province, northwestern Argentina). Its occupation span extends between the 13th and 15th centuries AD, but evidence diagnostic of the Inka Period (AD 1430-1536) is predominant. Residential Unit 1 was a h...

In [Ru2] we have classified the smooth projective symmetric G-varieties with Picard number one (and G semisimple). In this work we give a geometrical description of such varieties. In particular, we determine their group of automorphisms. When this group, Aut(X), acts non-transitively on X, we describe a G-equivariant embedding of the variety X in a homogeneous variety (with respect to a larger...

The efficient capture and conversion of solar energy into a usable form is a significant research target. Dye-sensitized systems, such as dye-sensitized solar cells (DSSCs) and watersplitting dye-sensitized photoelectrochemical cells (WSDSPECs), utilize high surface area metal oxide scaffolds sensitized with a molecular light-absorbing dye to harvest sunlight and convert it into an electrical p...

Knot theory has been known for a long time to be a powerful tool for the study of the topology of local isolated singular points of a plane algebraic curve. However it is rather recently that knot theory has been used to study plane algebraic curves in the large. Given a reduced plane algebraic curve C2 passing through the origin, let Lr = \ @B4 r be the intersection of with a round ball in C2 ...

Using the Hilbert Uniqueness Method, we study the problem of exact controllability in Neumann boundary conditions for problems of transmission of the wave equation. We prove that this system is exactly controllable for all initial states in L( ) (H( ))0. 1. Introduction. Throughout this paper, let be a bounded domain (open, connected, and nonempty) in R(n 1) with a boundary ÿ=@ of class C, and ...

This paper takes a doubting, though friendly, look at the hypotheses of “second generation deciine” and “segmented assimiiation” that have framed the emerging research agenda on the new second generation. We begin with a review of the basic approach, outlining the logic of argument, and specifying the central contentions.We then head toward the past, in search of material that will illuminate b...