1,721,252 research outputs found
Purification and molecular characterization of a novel protein factor from Phytophthora cactorum causing toxicity in plant
E. coli recA protein possesses a strand separating activity on short duplex DNAs
: RecA protein was found to catalyze the dissociation of the strands of a DNA substrate consisting of a 20-nucleotide primer annealed to circular single-stranded M13mp DNA. The strand separation reaction requires ATP hydrolysis and the presence of single-stranded DNA flanking the duplex DNA region to be unwound. RecA-catalyzed strand separation is effective only for very short duplexes, not exceeding 30 bp, and is not stimulated by single-stranded DNA-binding protein. These results are consistent with the ability of recA protein to disrupt regions of secondary structure in single-stranded DNA and to incorporate large non-homologies into heteroduplex DNA
Going Beyond Counting First Authors in Author Co-citation Analysis
The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
- …
