The aim of the present paper is to characterize associative rings R with unity in which 1+eR(1-e) terms some important class literature (for example, NR-rings, UU-rings, UJ-rings, UR-rings, exchange rings, 2-primal rings), where e2=e∈ and U(R) set units R.

in this paper we define a new type of rings ”almost powerhermitian rings” (a generalization of almost hermitian rings) and establish several sufficient conditions over a ring r such that, every regular matrix admits a diagonal power-reduction.

introduction radiofrequency planar microcoils are used to increase the resolution of magnetic resonance images of small samples. in this study, we aimed to design and fabricate a spiral planar microcoil constructed on a double-sided printed circuit board (pcb). it has four rings with an internal diameter of 241 microns tuned and matched at 63.8 mhz. materials and methods to achieve the maximum ...

BACKGROUND A "saddle-shaped" mitral annulus with an optimal ratio between annular height and commissural diameter may reduce leaflet and chordal stress and is purported to be conserved across mammalian species. Whether annuloplasty rings maintain this relationship is unknown. METHODS AND RESULTS Twenty-three adult sheep underwent implantation of radiopaque markers on the left ventricle and mi...

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...

The aim of this paper is to generalize the‎ ‎notion of almost valuation domains to arbitrary commutative‎ ‎rings‎. ‎Also‎, ‎we consider relations between almost valuation rings ‎and pseudo-almost valuation rings‎. ‎We prove that the class of‎ ‎almost valuation rings is properly contained in the class of‎ ‎pseudo-almost valuation rings‎. ‎Among the properties of almost‎ ‎valuation rings‎, ‎we sh...

specific structure of ewe's cervix is one of artificial insemination limitation in sheep. successful insemination in ewes has a close relation with morphology of their cervix. the objective of this experiment was to compare anatomical structure of cervix in makui, kurdish and afshari ewes. in this study, reproductive tract of 300 ewes of aforesaid sheep (100 ewes of each strain) were colle...