Two generated groups are universal

Evaluation of Shear Bond Strengths of Three Adhesive Materials Used to Retain Fiber Post in the Severely Damaged Primary Anterior Teeth

Background and Objective: Tooth decay and periodontal problems are among the most common human diseases which are considered unsolved health problems in most countries of the world. This study aimed to investigate and compare the shear bond strength of the fiber post with three different types of cement, including Glass ionomer, as well as Universal and Flowable composites. Materials and Metho...

Strength and Durability of a New Adhesive Bond to Superficial Dentin Using Etch and Rinse and Self-Etch Systems: An In Vitro Study

Background and Aim: Data regarding the efficacy of universal adhesives are limited. This study aimed to assess the durability of a universal adhesive bond to superficial dentin using etch and rinse and self-etch modes. Materials and Methods: In this in vitro, experimental study, 32 sound molars were randomly divided into two groups of Scotchbond Universal adhesive with two-step etch and rins...

Isomorphism of finitely generated solvable groups is weakly universal

We show that the isomorphism relation for finitely generated solvable groups of class 3 is a weakly universal countable Borel equivalence relation. This improves on previous results. The proof uses a modification of a construction of Neumann and Neumann. Elementary arguments show that isomorphism of finitely generated metabelian or nilpotent groups can not achieve this Borel complexity. In this...

A Class of Two Generated Automaton Groups on a Three Letter Alphabet

ar X iv : 1 30 6 . 12 70 v 1 [ m at h . L O ] 6 J un 2 01 3 UNIVERSAL COUNTABLE BOREL QUASI - ORDERS

In recent years, much work in descriptive set theory has been focused on the Borel complexity of naturally occurring classification problems, in particular, the study of countable Borel equivalence relations and their structure under the quasi-order of Borel reducibility. Following the approach of Louveau and Rosendal for the study of analytic equivalence relations, we study countable Borel qua...