The mineralogical composition and typological classification of a group 226 Axe-God pendants from the Jade pre-Columbian Culture Museum (from Instituto Nacional de Seguros) in San José (Costa Rica) was studied, using non-invasive characterization technique novel stylistic scheme. Possible composition-design correlations were examined through descriptive functional statistical analysis. This stu...

7 A homogeneous set of a graph G is a set X of vertices such that 2 ≤ |X| < |V (G)| 8 and no vertex in V (G) − X has both a neighbor and a non-neighbor in X. A graph 9 is prime if it has no homogeneous set. We present an algorithm to decide whether a 10 class of graphs given by a finite set of forbidden induced subgraphs contains infinitely 11 many non-isomorphic prime graphs. 12

In this paper, we obtain a forbidden minor characterization of a cographic matroid M for which the splitting matroid Mx,y is graphic for every pair x, y of elements of M .

A semigroup is amiable if there is exactly one idempotent in each R⇤-class and in each L⇤-class. A semigroup is adequate if it is amiable and if its idempotents commute. We characterize adequate semigroups by showing that they are precisely those amiable semigroups which do not contain isomorphic copies of two particular nonadequate semigroups as subsemigroups.

in this paper we give a characterization for all semigroups whose square is a group. moreover, we axiomatize such semigroups and study some relations between the class of these semigroups and grouplikes,introduced by the author. also, we observe that this paper characterizes and axiomatizes a class of homogroups (semigroups containing an ideal subgroup).  finally, several equivalent conditions ...

the non-commuting graph $nabla(g)$ of a non-abelian group $g$ is defined as follows: its vertex set is $g-z(g)$ and two distinct vertices $x$ and $y$ are joined by an edge if and only if the commutator of $x$ and $y$ is not the identity. in this paper we 'll prove that if $g$ is a finite group with $nabla(g)congnabla(bs_{n})$, then $g cong bs_{n}$, where $bs_{n}$ is the symmetric group of degre...

we regard the shearlet group as a semidirect product group andshow that its standard representation is,typically, a quasiregu-lar representation. as a result we can characterize irreducibleas well as square-integrable subrepresentations of the shearletgroup.

Abstract Humans often ‘altruistically’ punish non-cooperators in one-shot interactions among genetically unrelated individuals. This poses an evolutionary puzzle because altruistic punishment enforces cooperation norms that benefit the whole group but is costly for punisher. One key explanation follows a social-benefits logic: it eminently normative and group-functional (drawing on cultural sel...