Some results on cubic graphs

Pursuing a question of Oxley, we investigate whether the edge set of a graph admits a bipartition so that the contraction of either partite set produces a series-parallel graph. While Oxley\u27s question in general remains unanswered, our investigations led to two graph operations (Chapters 2 and 4) which are of independent interest. We present some partial results toward Oxley\u27s question in Chapter 3. The central results of the dissertation involve an operation on cubic graphs called the switch; in the literature, a similar operation is known as the edge slide. In Chapter 2, the author proves that we can transform, with switches, any connected, cubic graph on n vertices into any other connected, cubic graph on n vertices. Furthermore, connectivity, up to internal 4-connectedness, can be preserved during the operations. In 2007, Demaine, Hajiaghayi, and Mohar proved the following: for a fixed genus g and any integer k greater than or equal to 2, and for every graph G of Euler genus at most g, the edges of G can be partitioned into k sets such that contracting any one of the sets produces a graph of tree-width at most O(g^2 k). In Chapter 3 we sharpen this result, when k=2, for the projective plane (g=1) and the torus (g=2). During early simultaneous investigations of Jaeger\u27s Dual-Hamiltonian conjecture and Oxley\u27s question, we obtained a simple structure theorem on cubic, internally 4-connected graphs. That result is found in Chapter 4

Bounding tree-width via contraction on the projective plane and torus

If X is a collection of edges in a graph G, let G/X denote the contraction of X. Following a question of Oxley and a conjecture of Oporowski, we prove that every projective-planar graph G admits an edge-partition {X,Y} such that G/X and G/Y have tree-width at most three. We prove that every toroidal graph G admits an edge-partition {X,Y} such that G/X and G/Y have tree-width at most three and four, respectively

Notes on Phelps County ores

In conclusion, summing up the evidence both field and theoretic, there are very good reasons for believing that the deposits which have been worked and are not being worked are not the only deposits of magnitude in the county but by intelligent prospecting along lines already suggested other large and valuable deposits will be found. From the manner of the ores concentration it is not to be expected that every deposit will have a surface outcrop neither is it probable that every depression will be found to contain an ore deposit but when these phenomena occur, together with other evidences of mineralization, the condition at least warrents sic the expense of prospecting by pits or otherwise --page 17

Gene synthesis and expression of human torque teno virus VP3: Exploring the cancer-killing potential of an apoptin homolog

Torque teno virus (TTV) is a small, non-enveloped animal virus that contains a single-stranded, circular DNA genome of 3.8 kb. Related to chicken anemia virus (CAV), TTV\u27s ORF 3 may express a 105 residue protein which is homologous to CAV VP3 (apoptin)--a protein shown to multimerize and trigger apoptosis in cancer cells via a mechanism that involves nuclear translocation. Using gene synthesis, we generated the TTV ORF3 and expressed the gene fused to GFP. Here we demonstrate that TTV VP3 localizes to the cytoplasm of H1299 lung cancer cells and shows evidence of cytoplasmic aggregation. This aggregation is strikingly similar to CAV apoptin and may indicate a similar multimerization capacity for TTV VP3. However, an altered localization pattern may suggest a different mechanism of action

Executive Dismissal or Retention? A Study of Performance, Power, and Survival for College Basketball Coaches

This study applies upper echelons theory associated with executive dismissal and power to examine the relationships of performance and four types of executive power—structural, prestige, expert, and governance concentration—with dismissal. Using the context of National Collegiate Athletic Association college basketball, in which coaches are completely responsible for strategies and human capital acquisition and retention, a curvilinear relationship between performance and dismissal is found. Significant relationships for prestige and expert power with dismissal are also found, but the “honeymoon period” is longer than prior studies of executive and coach dismissal have shown. Surprisingly, concentrated governance is found to be negatively associated with the likelihood of dismissal