In this study, the relationship among four species of Polygonum (including P. hyrcanicum (three samples), P. persicaria, P. avicular, and P. hydropiper) was investigated by GC profiling. Furthermore, the major compounds of the ethylic ether extract of P. hyrcanicum were identified by GC/MS as: α-bisabolol (17.5%), cedrol (15.9%), sesquisabinene hydra...

Non-native species introductions are widespread and can affect ecosystem functioning by altering the structure of food webs. Invading plants often modify habitat structure, which may affect the suitability of vegetation as refuge and could thus impact predator-prey dynamics. Yet little is known about how the replacement of native by non-native vegetation affects predator-prey dynamics. We hypot...

microorganisms are important components of soil. some soil filamentous fungi such aspenicilium produce many bioactive small molecules, or secondary metabolites, that range frombeneficial bioactive compounds to harmful toxins. in this study, the metabolites of threepenicillium species (p. goditanum, p. moldavicum and p. corylophilum) were extracted byadding ethyl acetate to liquid cultures. the ...

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 $p$...

for a symmetric group $g:=sym(n)$ and a conjugacy class $mathcal{x}$ of involutions in $g$, it is known that if the class of involutions does not have a unique fixed point, then - with a few small exceptions - given two elements $a,x in mathcal{x}$, either $angbrac{a,x}$ is isomorphic to the dihedral group $d_{8}$, or there is a further element $y in mathcal{x}$ such that $angbrac{a,y} cong ang...