In this article, we introduce the concept of co-covering which is the dual of covering concept. Then, we prove several theorems being similar to the theorems that have been de-veloped for the covering concept. For example, we provide the lifting criterion for co-coverings of a topological space X, which helps us to classify them by subgroups of the group of all homeomorphisms of X.

this study is aimed to evaluate the effect of covering exposed root surface by collagen membrane and to compare this method with coronoally advanced flap covering. 26 teeth in 20 patients (12m/8f) with miller1 gingival recession were selected. 14 teeth were allocated into test group and 12 teeth in control group. following first phase of treatment, clinical parameters including the height and w...

‎In this paper‎, ‎we are interested in studying subgroups of topologized fundamental groups and their influences on generalized covering maps‎. ‎More precisely‎, ‎we find some relationships between generalized covering subgroups and the other famous subgroups of the fundamental group equipped with the compact-open topology and the whisker topology‎. ‎Moreover‎, ‎we present some conditions unde...

Abstract Let F be a finite extension of ${\mathbb Q}_p$ . $\Omega$ the Drinfeld upper half plane, and $\Sigma^1$ first covering We study affinoid open subset $\Sigma^1_v$ above vertex Bruhat–Tits tree for $\text{GL}_2(F)$ Our main result is that $\text{Pic}\!\left(\Sigma^1_v\right)[p] = 0$ , which we establish by showing $\text{Pic}({\mathbf Y})[p] ${\mathbf Y}$ Deligne–Lusztig variety $\text{S...