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Thomas, Steven, and Jeanne Hope Rabalais
No full textThomas, Steven, and Jeanne Hope Rabalais sitting on the walkwa
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Bernard and Thomas, Steven, and Jeanne Hope Rabalais
No full textBernard and his three children, two sons Thomas, Steven standing and baby Jeanne Hope on his la
Natural history and distribution of the enigmatic southern Appalachian opilionid, Fumontana deprehendor Shear (Laniatores: Triaenonychidae), with an assessment of morphological variation
No full textThomas, Steven M., Hedin, Marshal (2006): Natural history and distribution of the enigmatic southern Appalachian opilionid, Fumontana deprehendor Shear (Laniatores: Triaenonychidae), with an assessment of morphological variation. Zootaxa 1242 (1): 21-36, DOI: 10.11646/zootaxa.1242.1.
Molecular biology and enzymology of the HEM C locus of Escherichia coli K-12
No full textThe hem C locus of E. coli K12 encoding PBG deaminase was mapped on chromosomal DNA maintained within plasmids from the collection of Carbon and Clarke. The locus was sub-cloned as a 2.89 kb Sau3A fragment from one of the plasmids pLC41-4 into the BamHI site of pBR322. E. coli HB101 when transformed with the hybrid plasmid, designated pST46, exhibited 18 x the PBG deaminase activity of the parental strain. Selection of the recombinant plasmid harbouring hem C was by use of a novel fluorescence assay. Restriction endonuclease analysis of pST46 revealed the 2.89 kb insert was derived from a sequence adjacent to the cyaA locus on pLC41-4, as predicted from the results of comparative restriction endonuclease analysis of pLC41-4 with other plasmids harbouring the cyaA locus. The hem C locus was further sub-cloned into pBR322 as a 1.68 kb BAmHI-Sa mid I fragment. Two types of over-producing strains were obtained from the ligation and their plasmids were characterised. Both plasmids pST47 and pST48 carried the 1.68 kb BamHI-Sa mid I insert but further comparison revealed a 1.35 kb pBR322 derived sequence had been deleted from pST48 in the ligation procedure. This deletion was mapped and was shown to coincide with a gene encoding a DNA replication control protein. Enzyme activities in strains transformed with pST48 were increased as a result. The hem C locus was sequenced on both coding and non-coding strands using the methods of Sanger and Messing and necessitated the synthesis of eight oligonucleotide primers which were assembled using protected phosphoramidite nucleoside monomers. Examination of the sequence obtained revealed a large open reading frame preceded by the control sequences necessary for initiation of transcription and translation. Purification and N-terminal sequencing of E. coli PBG deaminase from the over-producing strain ST1048 identified the open reading frame as the hem C structural gene. Evidence for co-ordinate expression of protein from the hem C promoter was presented. Finally, the intergenic sequence between cyaA and hem C structural genes was defined and was found to be 387 base pairs. This information redefined the relative positions of both loci on the E. coli linkage map. (D72717/87)</p
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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