For a ring endomorphism $alpha$ and an $alpha$-derivation $delta$, we introduce a concept, so called skew $pi$-Armendariz ring, that is a generalization of both $pi$-Armendariz rings, and $(alpha,delta)$-compatible skew Armendariz rings. We first observe the basic properties of skew $pi$-Armendariz rings, and extend the class of skew $pi$-Armendariz rings through various ring extensions. We nex...

statement of the problem: implant-retained overdenture can improve the stability of dentures and prevent bone loss. overdenture-wearing patients need special hygiene care. purpose: the aim of this study was to evaluate the effects of various denture cleansers on the retention of dio orange o-rings. method and materials : in this experimental study, 40 dio orange o-rings were divided into 4 grou...

The aim of this paper is to generalize the‎‎notion of pseudo-almost valuation domains to arbitrary‎ ‎commutative rings‎. ‎It is shown that the classes of chained rings‎ ‎and pseudo-valuation rings are properly contained in the class of‎ ‎pseudo-almost valuation rings; also the class of pseudo-almost‎ ‎valuation rings is properly contained in the class of quasi-local‎ ‎rings with linearly ordere...

in this paper, we introduce the new notion of strongly j-clean rings associatedwith polynomial identity g(x) = 0, as a generalization of strongly j-clean rings. we denotestrongly j-clean rings associated with polynomial identity g(x) = 0 by strongly g(x)-j-cleanrings. next, we investigate some properties of strongly g(x)-j-clean.

We introduce the notion ofstrongly $alpha$-reversible rings which is a strong version of$alpha$-reversible rings, and investigate its properties. We firstgive an example to show that strongly reversible rings need not bestrongly $alpha$-reversible. We next argue about the strong$alpha$-reversibility of some kinds of extensions. A number ofproperties of this version are established. It is shown ...

in the present work, an extensive theoretical calculation study on histidine-histidine dipeptide in gas phase is done by using dft method with gaussian 98 program. through investigations on the molecular geometries of this molecule it is found that there is six rings in the molecules not two rings. the presence of four intramolecular hydrogen bonds is responsible for the formation of additional...

background and objective: evaluation of the results, safety, and stability of ferrara intracorneal ring segment (ficrs) implantation for keratoconus correction (age range was 24.39±8.32 years).   materials and methods: in this clinical trial study, 64 eyes of 57 patients with keratoconus and clear cornea that had ficrs implantation were studied. uncorrected visual acuity (ucva), best-spectacle ...

Introduction: Hydrogen sulfide (H2S) plays a key role in the regulation of vascular tone and protection of blood vessels against endothelial dysfunction. Since the mechanism of salt impairing H2S-induced vascular relaxation is not fully clear, therefore this study was designed to investigate the role of potassium (K+) channels in the vasodilatory effects of exogenous H2S in rat aortic rings.&nb...

In the present work, an extensive theoretical calculation study on Histidine-Histidine dipeptide in gas phase is done by using DFT method with Gaussian 98 program. Through investigations on the molecular geometries of this molecule it is found that there is six rings in the molecules not two rings. The presence of four intramolecular hydrogen bonds is responsible for the formation of additional...