a topoframe, denoted by $l_{ tau}$,  is a pair $(l, tau)$ consisting of a frame $l$ and a subframe $ tau $ all of whose elements are complementary elements in$l$. in this paper, we define and study the notions of a$tau $-real-continuous function on a frame $l$ and the set of realcontinuous functions $mathcal{r}l_tau $ as an $f$-ring.we show that $mathcal{r}l_{ tau}$is actually a generalization ...

for a fixed positive integer , we say a ring with identity is n-generalized right principally quasi-baer, if for any principal right ideal of , the right annihilator of is generated by an idempotent. this class of rings includes the right principally quasi-baer rings and hence all prime rings. a certain n-generalized principally quasi-baer subring of the matrix ring are studied, and connections...

The progesterone vaginal ring (PVR) Progering® has been shown to be effective as a contraceptive in breastfeeding women who need safe and effective methods of spacing pregnancies. Previous clinical trials, of 1-year duration, demonstrated its efficacy to be similar to that of the intra-uterine device (IUD) during lactation. The duration of lactational amenorrhoea is significantly prolonged in P...