From the ecosocial to the biosemiotic Although many pay lip-service to the view that signs are common to culture and biology, it remains unclear how such a unity could emerge. Indeed, while those working with culture usually ignore biology, biologists rarely consider how their observations bear on issues of meaning. So, when sign-making is studied, its outcomes are usually interpreted either ag...

In the most general way of speaking, people use the noun “memory” to refer to instances where information of the past is made available for present purposes. In this minimal sense the rings of trees are memories of the climatic conditions in the seasonal succession of years during certain periods of the past. The characteristic features of tree rings make available this information for the pres...

‎‎let r be a non-commutative ring with unity‎. ‎the commuting graph‎ ‎of $r$ denoted by $gamma(r)$‎, ‎is a graph with a vertex set‎ ‎$rsetminus z(r)$ and two vertices $a$ and $b$ are adjacent if and only if‎ ‎$ab=ba$‎. ‎in this paper‎, ‎we investigate non-commutative rings with unity of order $p^n$ where $p$ is prime and $n in lbrace 4,5 rbrace$‎. it is shown that‎, ‎$gamma(r)$ is the disjoint ...