1,720,966 research outputs found
Physiology and genetics of Rhodococcus aetherivorans BCP1 response to Arsenic
No full textArsenic ranks among the priority metals that are of public health significance. In the environment, the metalloid arsenic mainly exists under two forms: the arsenite [As(III)] and arsenate [As(V)]; the former being more toxic due to its high mobility and stability. Bacteria have developed multiple strategies for arsenic detoxification.
Rhodococcus aetherivorans BCP1 is able to cometabolize chlorinated compounds, mineralize a wide range of hydrocarbons1, resist different stress conditions2 and convert tellurite and selenite into less toxic forms3, making this strain an ideal candidate for microbial biotechnology applications. In this study, we assessed the ability of BCP1 to tolerate high concentrations of As(V) during its growth under aerobic conditions. Furthermore, different aspects regarding the arsenic homeostasis and the response of BCP1 to As(V) were investigated: (i) the different capability to convert As(V) into As(III) depending on the initial concentration of arsenate; (ii) the arsenic biosorption; (iii) the effect of arsenic on polyphosphate granule formation and (iv) the genetic/genomic aspects involved in arsenic detoxification. Finally, the detection of electrondense nanoparticles after the incubation with As(V) suggested the ability of BCP1 strain to generate As-based nanostructures
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
Exploitation of the strictly aerobic Rhodococcus aetherivorans BCP1 strain for the production of Selenium- and Tellurium-nanostructures
No full textTellurite (TeO32-) and selenite (SeO32-) are hazardous and toxic oxyanions for livingorganisms. However, microorganisms that tolerate and bioconvert these oxyanions to the lesstoxic and available form of elemental tellurium (Te0) and selenium (Se0) are seen as ideal candidates not only for bioremediation purposes, but also as novel cell factories to produce valuable metalloid-nanostructures. Here, Rhodococcus aetherivorans BCP1’s tolerance and
consumption of both TeO32- and SeO32- have been investigated, along with the production and characterization of metalloid-nanomaterials in the form of Se/Te-nanorods and Se-nanoparticles. BCP1 displayed a Minimal Inhibitory Concentration towards TeO32- and/or SeO32- of 11.2 and 500 mM, respectively, in rich medium under oxic conditions. Generally, pre-adapted BCP1 cells bioconverted a higher amount of oxyanions, regardless the initial concentrations of TeO3
2- (0.4 or 2 mM) and/or SeO32- (0.5 or 2 mM). Transmission Electron Microscopy and Energy-Dispersive X-Ray Spectroscopy showed stable and non-aggregated metalloid-nanomaterials surrounded by an organic coating, whose ability to self-assemble in the nanoscale was assessed through Dynamic Light Scattering. Finally, Zeta potential analyses revealed negative surface charges for both metalloid-nanomaterials and organic coating. We hypothesize that the biogenic Se/T
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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