objective: oxidative stress as a consequence of aging can induce infertility in males. in this study, we have investigated the effects of aging on sperm parameters, intra-spermatic water soluble antioxidants, reactive oxygen species (ros), and in vitro blastocyst formation. methods: we chose 5 older nmri male mice (10-12 months) and 5 younger nmri male mice (2-3 months). sperm parameters, ros, ...

seifert fibre groups (sf-gps) have been introduced and their first derived groups have been worked out in an earlier paper by the author [2,3]. now we aim to prove that they are residually soluble and residually finite.

a subgroup x of a group g is said to be an h -subgroup if n_g(x) ∩ x^g ≤ x for each element g belonging to g. in [m. bianchi e. a., on finite soluble groups in which normality is a transitive relation, j. group theory, 3 (2000), 147–156] the authors showed that finite groups in which every subgroup has the h -property are exactly soluble groups in which normality is a transitive relation. here ...

let $g$ be a finite $p$-soluble group‎, ‎and $p$ a sylow $p$-subgroup of $g$‎. ‎it is proved‎ ‎that if all elements of $p$ of order $p$ (or of order ${}leq 4$ for $p=2$) are‎ ‎contained in the $k$-th term of the upper central series of $p$‎, ‎then the $p$-length of‎ ‎$g$ is at most $2m+1$‎, ‎where $m$ is the greatest integer such that‎ ‎$p^m-p^{m-1}leq k$‎, ‎and the exponent of the image of $p$...