Naturally ordered bands

Varieties Generated by Ordered Bands I

Ordered bands are regarded as semirings whose multiplicative reduct is a band and whose additive reduct is a chain. We find the variety of semirings generated by all ordered bands and we determine part of the lattice of its subvarieties. Mathematics Subject Classification (2000): 16Y60, 08B05, 20M07.

A Note on Naturally Ordered Sets in Semi-metric Spaces

The dynein electrophoretic bands in axonemes naturally lacking the inner or the outer arm

Two unconventional sperm models (all motile) have been studied. The first one has only the outer arm on the doublets (the gall midge, Diplolaboncus); the second one, has only a well-developed inner arm (the eel, Anguilla). Both are devoid of central tubules and radial spokes. The gall midge sperm yields a single electrophoretic band migrating similarly to the sea urchin dynein band A; a major h...

A Class of Naturally Partly Ordered Commutative Archimedean Semi- Groups with Maximal Condition

Let 5 be a commutative semigroup. For a, b £5, we say that a divides b (or b is a multiple of a), and write a\b, if either a = b or ax = b for some x£5. We say that a properly divides b if a\b and b does not divide a. We call 5 archimedean if for all a, b £5, a divides some power of b. It is known that every commutative semigroup is uniquely expressible as a semilattice of archimedean semigroup...

Characterizing Ordered Bi-Ideals in Ordered Γ-Semigroups

The notion of a &Gamma-semigroup was introduced by Sen [8] in 1981. We can see that any semigroup can be considered as a &Gamma-semigroup. The aim of this article is to study the concept of (0-)minimal and max- imal ordered bi-ideals in ordered &Gamma-semigroups, and give some charac- terizations of (0-)minimal and maximal ordered bi-ideals in ordered &Gamma- semigroups analogous to the charact...