For integers p, q, s with p ≥ q ≥ 2 and s ≥ 0, let K−s 2 (p, q) denote the set of 2−connected bipartite graphs which can be obtained from Kp,q by deleting a set of s edges. In this paper, we prove that for any graph G ∈ K−s 2 (p, q) with p ≥ q ≥ 3, if 11 ≤ s ≤ q − 1 and ∆(G′) = s − 4, where G′ = Kp,q − G, then G is chromatically unique. This result extends both a theorem by Dong et al. [2] and ...

In this paper we determine the graphs chromatically equivalent to the generalized wheel C5 + [{n'

Let P(G) denote the chromatic polynomial of a graph G. Two graphs G and H are chromatically equivalent, if P(G) = P(H). A set of graphs S is called a chromatic equivalence class if for any graph H that is chromatically equivalent with a graph G in S, then H ∈S. Peng et al. (Discrete Math. 172 (1997) 103–114), studied the chromatic equivalence classes of certain generalized polygon trees. In thi...

Superfusion with 200 microM 2-amino-4-phosphonobutyrate (APB) of dark and chromatically adapted frog eyecups caused marked potentiation of the ERG OFF-response (d-wave). Blockade of the glycinergic synapses by strychnine did not change this effect at all. Blockade of the GABAergic synapses by picrotoxin slightly diminished the effect of APB in chromatically-adapted eyes with isolated cones' act...

Let H = (X,E) be a simple hypergraph and let f (H, ) denote its chromatic polynomial. Two hypergraphs H1 and H2 are chromatic equivalent if f (H1, ) = f (H2, ). The equivalence class of H is denoted by 〈H 〉. Let K and H be two classes of hypergraphs.H is said to be chromatically characterized in K if for every H ∈ H ∩K we have 〈H 〉 ∩K=H ∩K. In this paper we prove that uniform hypertrees and uni...

Two graphs are defined to be adjointly equivalent if their complements are chromatically equivalent. We study the properties of two invariants under adjoint equivalence.

Unique yellow is considered to represent the equilibrium point of the red-green opponent chromatic mechanism. There are several hypotheses that attempt to explain how this equilibrium point is established. The determinant for unique yellow, however, has not yet been clarified. Here we explored whether the L/M cone ratio or visual information determines unique yellow. If the former is the case, ...

An h-uniform hypergraph (h ≥ 2) H = (V, E) of order n = |V| and size m = |E|, consists of a vertex set V(H) = V and edge set E(H) = E , where E ⊂ V and |E| = h for each edge E in E . H is said to be linear if 0 ≤ |E ∩ F | ≤ 1 for any two distinct edges E,F ∈ E(H) [1]. Let P h,1 p denote the linear path consisting of p ≥ 1 edges E1, . . . , Ep such that |E1| = . . . = |Ep| = h, |Ek ∩ El| = 1 if ...

Color filters are widely used in color displays, optical measurement devices, and imaging devices. Conventional color filters have usually only one fixed output color. However developing active color filters with controllable color output can lead to more compact and sophisticated color filter-based devices and applications. Recent progress in nanotechnology and new knowledge of the interaction...