1,721,305 research outputs found
Genome Organization and Adaptive Potential of Archetypal Organophosphate Degrading Sphingobium fuliginis ATCC 27551
Sphingobium fuliginis ATCC 27551, previously classified as Flavobacterium sp. ATCC 27551, degrades neurotoxic organophosphate insecticides and nerve agents through the activity of a membrane-associated organophosphate hydrolase. This study was designed to determine the complete genome sequence of S. fuliginis ATCC 27551 to unravel its degradative potential and adaptability to harsh environments. The 5,414,624 bp genome with a GC content of 64.4% is distributed between two chromosomes and four plasmids and encodes 5,557 proteins. Of the four plasmids, designated as pSF1, pSF2, pSF3, and pSF4, only two (pSF1 and pSF2) are self-transmissible and contained the complete genetic repertoire for a T4SS. The other two plasmids (pSF3 and pSF4) are mobilizable and both showed the presence of an oriT and relaxase-encoding sequences. The sequence of plasmid pSF3 coincided with the previously determined sequence of pPDL2 and included an opd gene encoding organophosphate hydrolase as a part of the mobile element. About 15,455 orthologous clusters were identified from among the cumulatively annotated genes of 49 Sphingobium species. Phylogenetic analysis done using the core genome consisting of 802 orthologous clusters revealed a close relationship between S. fuliginis ATCC 27551 and bacteria capable of degradation of polyaromatic hydrocarbon compounds. Genes coding for transposases, efflux pumps conferring resistance to heavy metals, and TonR-type outer membrane receptors are selectively enriched in the genome of S. fuliginis ATCC 27551 and appear to contribute to the adaptive potential of the organism to challenging and harsh environments
Diagnostic segmental Nerve Root Blocks in Patients with Chronic Radiating Low Back Pain: Bringing light to the Darkness?
Contains fulltext :
27551.pdf (Publisher’s version ) (Open Access)RU Radboud Universiteit Nijmegen, 10 mei 2006Promotor : Crul, B.J.P. Co-promotores : Groen, G.J., Wilder-Smith, O.H.G.[120] p
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
Variations on the Author
“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
We 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
Multiple mechanisms contribute to lateral transfer of an organophosphate degradation (opd) island in Sphingobium fuliginis ATCC 27551
The complete sequence of pPDL2 (37,317 bp), an indigenous plasmid of Sphingobium fuliginis ATCC 27551 that encodes genes for organophosphate degradation (opd), revealed the existence of a site-specific integrase (int) gene with an attachment site attP, typically seen in Integrative Mobilizable Elements (IME). In agreement with this sequence information, site-specific recombination was observed between pPDL2 and an artificial plasmid having a temperature-sensitive replicon and a cloned attB site at the 3′ end of the seryl tRNA gene of Sphingobium japonicum. The opd gene cluster on pPDL2 was found to be part of an active catabolic transposon with mobile elements y4qE and Tn3 at its flanking ends. Besides the previously reported opd cluster, this transposon contains genes coding for protocatechuate dioxygenase and for two transport proteins from the major facilitator family that are predicted to be involved in transport and metabolism of aromatic compounds. A pPDL2 derivative, pPDL2-K, was horizontally transferred into Escherichia coli and Acinetobacter strains, suggesting that the oriT identified in pPDL2 is functional. A well-defined replicative origin (oriV), repA was identified along with a plasmid addiction module relB/relE that would support stable maintenance of pPDL2 in Sphingobium fuliginis ATCC 27551. However, if pPDL2 is laterally transferred into hosts that do not support its replication, the opd cluster appears to integrate into the host chromosome, either through transposition or through site-specific integration. The data presented in this study help to explain the existence of identical opd genes among soil bacteria
Dispelling the Myths Behind First-author Citation Counts
We 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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