Several authors have studied the graphs for which every edge is a chord of a cycle; among 2-connected graphs, one characterization is that the deletion of one vertex never creates a cut-edge. Two new results: among 3-connected graphs with minimum degree at least 4, every two adjacent edges are chords of a common cycle if and only if deleting two vertices never creates two adjacent cut-edges; am...

The 552 amino acid vaccinia virus DNA ligase consists of three structural domains defined by partial proteolysis: (i) an amino-terminal 175 amino acid segment that is susceptible to digestion with chymotrypsin and trypsin; (ii) a protease-resistant central domain that contains the active site of nucleotidyl transfer (Lys-231); (iii) a protease-resistant carboxyl domain. The two protease-resista...

NsrR from Streptomyces coelicolor (Sc) regulates the expression of three genes through the progressive degradation of its [4Fe-4S] cluster on nitric oxide (NO) exposure. We report the 1.95 Å resolution crystal structure of dimeric holo-ScNsrR and show that the cluster is coordinated by the three invariant Cys residues from one monomer and, unexpectedly, Asp8 from the other. A cavity map suggest...

DNA dependent protein kinase (DNA-PK) plays a central role in the non-homologous end-joining pathway of DNA double strand break repair. Its catalytic subunit (DNA-PK(CS)) functions as a serine/threonine protein kinase. We show that DNA-PK forms a stable complex at DNA termini that blocks the action of exonucleases and ligases. The DNA termini become accessible after autophosphorylation of DNA-P...

This paper discusses the knowledge transfer process in offshore outsourcing. The focus is a case study of software offshore outsourcing from Japan to Vietnam. Initial results confirm that willingness to cooperate and good impressions facilitate the knowledge transfer process. In addition, communication barriers, cultural differences, lack of equivalence in individual competence, and lack of com...

A conjecture of Fan and Raspaud [3] asserts that every bridgeless cubic graph contains three perfect matchings with empty intersection. Kaiser and Raspaud [6] suggested a possible approach to this problem based on the concept of a balanced join in an embedded graph. We give here some new results concerning this conjecture and prove that a minimum counterexample must have at least 32 vertices.

The oriented diameter of a bridgeless graph G is min{diam(H) |H is an orientation of G}. A path in an edge-colored graph G, where adjacent edges may have the same color, is called rainbow if no two edges of the path are colored the same. The rainbow connection number rc(G) of G is the smallest integer k for which there exists a k-edge-coloring of G such that every two distinct vertices of G are...

The final cleavage event that terminates cell division, abscission of the small, dense intercellular bridge, has been particularly challenging to resolve. Here, we describe imaging innovations that helped answer long-standing questions about the mechanism of abscission. We further explain how computational modeling of high-resolution data was employed to test hypotheses and generate additional ...

Relational Match to Sample (RMTS) is a common test of relational reasoning involving matching cards based on the relations “same” and “different”. Children below the age of five fail RMTS, even with corrective feedback. Given that success on RMTS depends on the ability to represent and compare ”same” and ”different”, such failure has been interpreted as indicative of the absence of these abilit...

This study redescribes an arthroscopic bridge technique for repair of avulsion of the posterior cruciate ligament. The procedure is performed step-to-step. In this technique we created two bone tunnels in the anterior aspect of the tibia and inferior medial of the tibia tuberosity and then create suture fixation of the fragment using the suture bridge. The arthroscopic bridge technique was used...