Rapid, effective communication between colony members is a key attribute that enables ants to live in dominant, fiercely protected societies. Their signals, however, may be mimicked by other insects that coexist as commensals with ants or interact with them as mutualists or social parasites. We consider the role of acoustics in ant communication and its exploitation by social parasites. Social ...

The spines of flowering plants are thought to function primarily in defence against mammalian herbivores; however, we previously reported that feeding by Manduca sexta caterpillars on the leaves of horsenettle plants (Solanum carolinense) induces increased development of internode spines on new growth. To determine whether and how spines impact caterpillar feeding, we conducted assays with thre...

We present a novel, yet simple, technique for the speciication of context in structured documents that we call caterpillar expressions. Although we are primarily applying this technique in the speciication of context-dependent style sheets for HTML, SGML and XML documents, it can also be used for query speciica-tion for structured documents, as we shall demonstrate, and for the speciication of ...

Cabbage loopers ( Trichoplusia ni ) are herbivores that commonly preyed upon by many different species of parasitoid wasps. These wasps reproduce injecting its gestated eggs into 2-3 rd instar caterpillars. After injection wasp eggs, studies have shown some caterpillars will shift behavior in reaction to the injection. The result hatching is termination caterpillar. I specifically look at this ...

A caterpillar is a tree with the property that after deleting all its vertices of degree 1 a simple path is obtained. The signed 2-domination number γ s (G) and the signed total 2-domination number γ st(G) of a graph G are variants of the signed domination number γs(G) and the signed total domination number γst(G). Their values for caterpillars are studied.

A graph G is called a pairwise compatibility graph (PCG) if there exists an edge-weighted tree T and two non-negative real numbers dmin and dmax such that each leaf lu of T corresponds to a vertex u ∈ V and there is an edge (u, v) ∈ E if and only if dmin ≤ dT,w(lu, lv) ≤ dmax where dT,w(lu, lv) is the sum of the weights of the edges on the unique path from lu to lv in T . In this paper, we conc...

is minimized. We denote B(G) = minf B(G, f) to be the bandwidth of G. This is equivalent to the matrix bandwidth minimization problem, which is the form it was introduced in the 1960s. In the matrix version of the problem, a symmetric matrix M is given, and the goal is to find a permuation matrix P such that the nonzero entries of PMP are all within a “band of minimum width” about the diagonal....

a graceful labeling of a graph g of size n is an injective assignment of integers from {0, 1,..., n} to the vertices of g, such that when each edge of g has assigned a weight, given by the absolute dierence of the labels of its end vertices, the set of weights is {1, 2,..., n}. if a graceful labeling f of a bipartite graph g assigns the smaller labels to one of the two stable sets of g, then f...

We give the first polynomial-time algorithm that computes the bandwidth of bipartite permutation graphs. Bandwidth is an NP-complete graph layout problem that is notorious for its difficulty even on small graph classes. For example, it remains NP-complete on caterpillars of hair length at most 3, a very restricted subclass of trees. Much attention has been given to designing approximation algor...

This paper studies the computational complexity of the Proper interval colored graph problem (picg), when the input graph is a colored tree. We show that the problem is hard for the class of caterpillar trees. To prove our result we make use of a close relationship between intervalizing problems and graph layout problems. We deene a graph layout problem the Proper colored layout problem (pclp)....