McGill University Thèses et mémoires par auteur commençant par L

In this thesis we study the structure and basic properties of centroids, or maximal rings of scalars, for various classes of exponential groups. The theorems obtained completely describe the structure of centroids for the important class of CSA-groups, which allows us to obtain as a corollary the corresponding results for torsion-free hyperbolic groups, groups acting freely on $ Lambda$-trees, and universally free groups. We also consider this problem for other classes of groups, such as nilpotent groups, and for free group constructions. General aspects of the theory of exponential groups are discussed in sufficient detail.  Lire la suite

This thesis contains a description of centroids, or maximal rings of scalars, for the class of CSA-groups, including free, universally free, and torsion-free hyperbolic groups. We also describe centroids of free products of groups, R-free nilpotent groups, and UTn(R), where R is a binomial ring. Using the results about the structure of centroids for R-free nilpotent groups, we solve the long-standing problem of rigidity for R-free nilpotent groups, posed by F. Grunewald and D. Segal. We also establish the rigidity of the groups UTn( R).  Lire la suite

In this thesis we construct the tensor A-completion over an arbitrary torsion-free ring A for groups whose maximal abelian subgroups are either conjugate separated or A-modules. As a corollary, this result gives us an explicit description of the structure of tensor completion for groups of the form $F/N sp prime,$ in particular, for free solvable groups. Moreover, it is proved that the class of A-faithful groups is closed under free products. We also discuss some general aspects of the theory of exponential groups and tensor completions.  Lire la suite

Formulation studies of value-added seafood nuggets were done using appropriate mixtures of surimi, kamaboko, broken shrimp, and shrimp broth made from shrimp processing waste. A total of 19 formulations were prepared and, on the basis of sensory analysis, two formulations (comprising of 75% surimi: 25% shrimp, and 100% surimi containing shrimp broth) were used throughout this study. Initial storage trials of both raw and cooked battered and breaded value-added nuggets in air and under various modified atmospheres (MAP) showed that a microbiological shelf-life of 28 d was possible for cooked nuggets at 4 and 12$ sp circ$C packaged under various …  Lire la suite