1,720,977 research outputs found
Phylogentic characterization of epibiotic bacteria associated with the accessory nidamental gland and the egg capsules of the Squid Loligo pealei (Cephalopoda: Loliginidae)
No full textSexually mature female squid Loligo pealei harbour dense bacterial communities in their accessory nidamental glands (ANGs) and in their egg capsules (ECs). This study describes a molecular approach using the 16S rRNA gene (rDNA) to identify bacterial populations within the ANG and the ECs of the North Atlantic squid species L. pealei. Fluorescent in situ hybridization (FISH) and 16S rDNA analysis showed that predominantly alpha- and, to a lesser extent, gamma-proteobacteria were the predominant components of the ANG and EC bacterial communities. Sequencing results showed the presence of alpha-proteobacterial populations affiliated with the Roseobacter group and additional deep-branching alpha-proteobacterial lineages. In contrast, isolates from the ANG and ECs contained only a few alpha-proteobacteria of the Roseobacter group compared with several gamma-proteobacterial isolates, mostly Shewanella and Pseudoalteromonas species. Most of the ANG-associated bacterial populations were also found within the ECs of L. pealei. The molecular approach allowed the visualization of alpha-proteobacteria as major constituents of a bacterial symbiosis within the reproductive system of the Loliginidae
Shewanella pealeana sp. nov., a member of a microbial community associated with the accessory nidamental gland of the squid Loligo pealei.
No full textA new, mesophillic, facultatively anaerobic, psychrotolerant bacterium, strain ANG-SQ1T (T = type strain), was isolated from a microbial community colonizing the accessory nidamental gland of the squid Loligo pealei. It was selected from the community on the basis of its ability to reduce elemental sulfur. The cells are motile, Gram-negative rods (2.0-3.0 microns long, 0.4-0.6 micron wide). ANG-SQ1T grows optimally over the temperature range of 25-30 degrees C and a pH range of 6.5-7.5 degrees C in media containing 0.5 M NaCl. 16S rRNA sequence analysis revealed that this organism belongs to the gamma-3 subclass of the Proteobacteria. The closest relative of ANG-SQ1T is Shewanella gelidimarina, with a 16S rRNA sequence similarity of 97.0%. Growth occurs with glucose, lactate, acetate, pyruvate, glutamate, citrate, succinate, Casamino acids, yeast extract or peptone as sole energy source under aerobic conditions. The isolate grows anaerobically by the reduction of iron, manganese, nitrate, fumarate, trimethylamine-N-oxide, thiosulfate or elemental sulfur as terminal electron acceptor with lactate. Growth of ANG-SQ1T was enhanced by the addition of choline chloride to growth media lacking Casamino acids. The addition of leucine or valine also enhanced growth in minimal growth media supplemented with choline. The results of both phenotypic and genetic characterization indicate that ANG-SQ1T is a Shewanella species. Thus it is proposed that this new isolate be assigned to the genus Shewanella and that it should be named Shewanella pealeana sp. nov., in recognition of its association with L. peale
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
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
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