Reconstructing the evolutionary history of a set of species is an elementary problem in biology, and methods for solving this problem are evaluated based on two characteristics: accuracy and efficiency. Neighbor-joining reconstructs phylogenetic trees by iteratively picking a pair of nodes to merge as a new node until only one node remains; due to its good accuracy and speed, it has been e...

In this work we consider hierarchical clustering algorithms, such as UPGMA, which follow the closest-pair joining scheme. We survey optimal O(n)-time implementations of such algorithms which use a ‘locally closest’ joining scheme, and specify conditions under which this relaxed joining scheme is equivalent to the original one (i.e. ‘globally closest’).

The "neighbor-joining algorithm" is a recursive procedure for reconstructing trees that is based on a transformation of pairwise distances between leaves. We present a generalization of the neighbor-joining transformation, which uses estimates of phylogenetic diversity rather than pairwise distances in the tree. This leads to an improved neighbor-joining algorithm whose total running time is st...

XLF/Cernunnos is a core protein of the nonhomologous end-joining pathway of DNA double-strand break repair. To better define the role of Cernunnos in end joining, whole-cell extracts were prepared from Cernunnos-deficient human cells. These extracts effected little joining of DNA ends with cohesive 5' or 3' overhangs, and no joining at all of partially complementary 3' overhangs that required g...

A chromosomal segment with a unique structure around the immunoglobulin heavy chain joining region (JH) has been molecularly cloned from an Abelson murine leukemia virus-transformed cell line. Attached to JH3 in the cloned DNA, in inverted sequence, is the DNA from JH1 to the JH2 recognition sequence. The inverted segment is attached at its other end to the 5' recognition sequence of a diversit...

This paper overviews heterogeneous exothermic reactive systems as they apply to the joining of materials. Techniques that are investigated fall under two general schemes: so-called Volume Combustion Synthesis (VCS) and Self-Propagating High-Temperature Synthesis (SHS). Within the VCS scheme, applications that are considered include Reactive Joining (RJ), Reactive Resistance Welding (RRW), and S...