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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
Comparative Analysis Of Secondary Metabolite Biosynthetic Gene Clusters And Associated P450S In The Genera Streptomyces And Mycobacterium
Get PDFSpecies belonging to the genera Streptomyces and Mycobacterium are well known for their contrasting lifestyle and impact on humans. Streptomyces species produce two-thirds of antibiotics, secondary metabolites, used in the world, whereas mycobacterial species are well known to be the deadliest human pathogens, although a few are environmentally useful. Mycobacterial species also produce secondary metabolites that play a role in pathogenesis. It is a well known fact that genes involved in the synthesis of secondary metabolites form clusters known as biosynthetic gene clusters (BGCs). To date, comparative analysis of secondary metabolite BGCs in species belonging to these two genera has not been reported. Among the genes involved in synthesis of secondary metabolites, cytochrome P450 monooxygenases (CYPs/P450s) play a key role, as these enzymes contribute to the diversity of secondary metabolites owing to their chemo-, stereo- and regio-specific oxidation of substrates. Despite this importance of P450s in the synthesis of secondary metabolites, to date, identification of P450s involved in the synthesis of secondary metabolites in species belonging to these two genera has not been reported. Thus, this study is aimed at addressing these two research gaps by conducting comprehensive comparative analysis of secondary metabolite BGCs and associated P450s in the species belonging to the genera Streptomyces (48 species) and Mycobacterium (60 species).
Genome-wide analysis revealed the presence of a large and diverse number of secondary metabolite BGCs in Streptomyces species compared to mycobacteria species. In total 1 461 secondary metabolite BGCs belonging to 159 types were found in 48 Streptomyces species compared to 898 secondary metabolite BGCs belonging to only 18 types found in 60 mycobacterial species. Among Streptomyces species, S. griseochromogenes has the highest number of secondary metabolite BGCs (49) and Streptomyces sp. 4F has the lowest number of secondary metabolite BGCs (19) in their genomes. Mycobacterium marinum has the highest number of secondary metabolite BGCs (29) and two strains of M. leprae have the lowest number of secondary metabolite BGCs (five each) in their genomes. Quite a big difference was observed with respect to the types of secondary metabolite BGCs between Streptomyces and mycobacterial species. Among 159 types of secondary metabolite BGCs found in Streptomyces species, only 13 types of BGCs contributed 80% to the total percentage of BGCs, suggesting that the secondary metabolites produced by these BGCs were highly important in Streptomyces species’ physiology. The secondary metabolite BGC, terpene, was dominant, followed by siderophores, nonribosomal peptides (Nrps) and Type 1 polyketides (T1pks) in Streptomyces species. Among 18 types of secondary metabolite BGCs identified in mycobacterial species, Nrps was the dominant secondary metabolite BGC, followed by ‘other’, T1pks and T1pks-Nrps. Despite the presence of 15 common types of secondary metabolite BGCs between the genera Streptomyces and Mycobacterium, large differences were observed in terms of the number of BGCs, indicating that the selective enrichment of particular secondary metabolite BGCs in both genera is possibly due to the different lifestyle, as discussed in the subsequent section. Comparative analysis of P450s that are part of secondary metabolite BGCs revealed the presence of a large number of diverse P450s as part of these secondary metabolite BGCs in Streptomyces, compared to Mycobacterium. Not all secondary metabolite BGCs found in Streptomyces and Mycobacterium have P450s. Among 1 461 Streptomyces species, only 554 secondary metabolite BGCs were found to have P450s, whereas in mycobacterial species, among 898 only 204 secondary metabolite BGCs have P450s. Overall, 554 and 204 P450s were found to be part of secondary metabolite BGCs in respectively Streptomyces and mycobacterial species. Among 88 P450 families that are part of different secondary metabolite BGCs, some P450 families are highly dominant in Streptomyces species, indicating their key role in the synthesis of different secondary metabolites. These P450 families were found to be the same that are highly populated in Streptomyces species, with some exceptions. This strongly indicates that these P450 families provide an advantage to Streptomyces species by generating diverse secondary metabolites, thus letting these species thrive in nature. Mycobacterial species’ secondary metabolite BGC P450 profiles are contrasted with Streptomyces species, where the dominant P450 families are not necessarily dominant as part of secondary metabolite BGCs. Ten P450 families, namely CYP51, CYP123, CYP125, CYP130, CYP135, CYP136, CYP138, CYP140, CYP144 and CYP1128, are conserved and highly populated across 60 mycobacterial species. However, none of these P450 families is dominant as part of different secondary metabolite BGCs. The CYP139 P450 family was found to be the dominant family as part of secondary metabolite BGCs. Although eight P450 families, namely CYP124, CYP121, CYP105, CYP125, CYP102, CYP147, CYP136 and CYP161, which are part of secondary metabolite BGCs, were commonly found between the genera Streptomyces and Mycobacterium, the number of P450s in these families was found to be different.
Based on the above data, it is clear that different lifestyles influenced the gene content in Streptomyces and Mycobacterium, hence differences in the number and type of secondary metabolite BGCs and P450s that are associated with secondary metabolite BGCs were observed. The saprophytic and symbiotic lifestyle of Streptomyces resulted in the highest diversity of secondary metabolite BGCs and P450s, thus helping these organisms to generate chemically diverse secondary metabolites to adapt to different ecological niches. For this reason, Streptomyces species have been found to have large and diverse secondary metabolite BGCs and P450s compared to mycobacterial species. Based on the evidence presented in this study, the researcher hereby proposes that lifestyle or ecological niches play a key role in the evolution of secondary metabolite BGCs and associated P450s in species belonging to the genera Streptomyces and Mycobacterium
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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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