A preservation theorem for theories without the tree property of the first kind

We prove that the NTP$_1$ property of a geometric theory $T$ is inherited by theories of lovely pairs and $H$-structures associated to $T$. We also provide a class of examples of nonsimple geometric NTP$_1$ theories

Dimension, matroids, and dense pairs of first-order structures

A structure M is pregeometric if the algebraic closure is a pregeometry in all M' elementarily equivalent to M. We define a generalisation: structures with an existential matroid. The main examples are superstable groups of U-rank a power of omega and d-minimal expansion of fields. Ultraproducts of pregeometric structures expanding a field, while not pregeometric in general, do have an unique existential matroid. Generalising previous results by van den Dries, we define dense elementary pairs of structures expanding a field and with an existential matroid, and we show that the corresponding theories have natural completions, whose models also have a unique existential matroid. We extend the above result to dense tuples of structures.Comment: Version 2.8. 61 page

Stability in Geometric Theories

34 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2004.The second question is answered for o-minimal structures that eliminate imaginaries. It is proved that for any structure D whose theory is o-minimal and eliminates imaginaries, any stable group interpretable in D is totally transcendental with finite Morley rank. A strengthening of Buechler's Dichotomy Theorem is also proved for stable (viz. superstable) structures that are interpretable in D.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD

Ética, responsabilidad social y empresa

Tomado de: http://mapeo-rse.info/sites/default/files/Etica_responsabilidad_social_y_empresa.pdf Maestría en Planificación y Gestión de Negocios de Alimentos y Bebidas; Negocios de A y B con Responsabilidad Social, 4to. Semestr