We study periodic rings that are finitely generated as groups. We prove several structure results. We classify periodic rings that are free of rank at most 2, and also periodic rings R such that R is finitely generated as a group and R/t(R) Z. In this way, we construct new classes of periodic rings. We also ask a question concerning the connection to periodic rings that are finitely generated a...

genotype by environment interaction is one of the most important subjects in crop improvement, so that different statistical measures have been proposed to estimate this interaction. in the present study, nine varieties and hybrids of spring rapeseed were evaluated in five warm dryland areas including sarpol-e-zahab, gonbad, gachsaran, pol-e-dukhtar and masjedsoliman in two growing seasons 2002...

Let Γ be a finitely generated, torsion-free, two step nilpotent group. Let C(Γ) be the universal C∗-algebra of Γ. We show that acsr(C∗(Γ)) = acsr(C((Γ̂)1), where for a unital C∗-algebra A, acsr(A) is the absolute connected stable rank of A, and where (Γ̂)1 is the space of one-dimensional representations of Γ. For the case of stable rank, we have close results. In the process, we give a stable ran...