1,721,038 research outputs found

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    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

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    “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

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    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

    Dispelling the Myths Behind First-author Citation Counts

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    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

    Author Index

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    A fast and low-cost spray method for prototyping and depositing surface-enhanced Raman scattering arrays on microfluidic paper based device

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    In this study, a fast, low-cost, and facile spray method was proposed. This method deposits highly sensitive surface-enhanced Raman scattering (SERS) silver nanoparticles (AgNPs) on the paper-microfluidic scheme. The procedures for substrate preparation were studied including different strategies to synthesize AgNPs and the optimization of spray cycles. In addition, the morphologies of the different kinds of paper substrates were characterized by SEM and investigated by their SERS signals. The established method was found to be favorable for obtaining good sensitivity and reproducible results. The RSDs of Raman intensity of randomly analyzing 20 spots on the same paper or different filter papers depositing AgNPs are both below 15%. The SERS enhancement factor is approximately 2 x 10(7). The whole fabrication is very rapid, robust, and does not require specific instruments. Furthermore, the total cost for 1000 pieces of chip is less than $20. These advantages demonstrated the potential for growing SERS applications in the area of environmental monitoring, food safety, and bioanalysis in the future

    Brushing, a simple way to fabricate SERS active paper substrates

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    A simple and facile method has been demonstrated to fabricate low-cost surface enhanced Raman scattering (SERS) active microfluidic paper chips using a painting brush. This strategy solves the problem of mass production of highly reproducible SERS substrates without complicated or bulky micro-or nanofabrication instruments. Rhodamine 6G (R6G) was chosen as a probe molecule to evaluate the performance of the SERS active chip. To further demonstrate the possibility of this method's potential application in environmental monitoring, trace malachite green (MG) was successfully analyzed on this chip. The performance of our chips was desirable. The paper substrates with silver nanoparticles deposited by brush were found to be cost-efficient and highly sensitive (LOD for R6G and MG are 1 nM and 10 nM, respectively), and have good reproducibility (similar to 15% relative standard deviation)

    A glutathione S-transferase from Proteus mirabilis involved in heavy metal resistance and its potential application in removal of Hg2+

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    Glutathione S-transferases (GSTs) are a family of multifunctional proteins playing important roles in detoxification of harmful physiological and xenobiotic compounds in organisms. In our study, a gene encoding a GST from Proteus mirabilis strain V7, gst(Pm)-4, was cloned and conditionally expressed in Escherichia coli strain BL21(DE3). The purified Gst(Pm)-4 protein, with an estimated molecular mass of approximately 23 kDa, was able to conjugate 1-chloro-2,4-dinitrobenzene and bind to the GSH-affinity matrix. Real-time reverse transcriptase PCR suggested that mRNA level of gst(Pm)-4 was increased in the presence of CdCl2, CuCl2, HgCl2 and PbCl2, respectively. Correspondingly, overexpression of gst(Pm)-4 in the genetically engineered bacterium Top10/pLacpGst exhibited higher heavy metal resistance compared to the control Top10/pLacP3. Another genetically engineered bacterium Top10/pBATGst, in which the DNA encoding Gst(Pm)-4 protein was fused with the DNA encoding Pfa1-based auto surface display system, was built. Top10/pBATGst could constitutively express the chimeric Gst(Pm)-4 and anchor it onto the cell surface subsequently. Almost 100% of the Hg2+ within the range of 0.1-100 nM was adsorbed by Top10/pBATGst, and 80% of the bounded Hg2+ could be desorbed from bacterial cells when pH was adjusted to 6.0. Thus, Top10/pBATGst can be potentially used for efficient treatment of Hg2+-contaminated aquatic environment. (C) 2013 Elsevier B.V. All rights reserved.Glutathione S-transferases (GSTs) are a family of multifunctional proteins playing important roles in detoxification of harmful physiological and xenobiotic compounds in organisms. In our study, a gene encoding a GST from Proteus mirabilis strain V7, gst(Pm)-4, was cloned and conditionally expressed in Escherichia coli strain BL21(DE3). The purified Gst(Pm)-4 protein, with an estimated molecular mass of approximately 23 kDa, was able to conjugate 1-chloro-2,4-dinitrobenzene and bind to the GSH-affinity matrix. Real-time reverse transcriptase PCR suggested that mRNA level of gst(Pm)-4 was increased in the presence of CdCl2, CuCl2, HgCl2 and PbCl2, respectively. Correspondingly, overexpression of gst(Pm)-4 in the genetically engineered bacterium Top10/pLacpGst exhibited higher heavy metal resistance compared to the control Top10/pLacP3. Another genetically engineered bacterium Top10/pBATGst, in which the DNA encoding Gst(Pm)-4 protein was fused with the DNA encoding Pfa1-based auto surface display system, was built. Top10/pBATGst could constitutively express the chimeric Gst(Pm)-4 and anchor it onto the cell surface subsequently. Almost 100% of the Hg2+ within the range of 0.1-100 nM was adsorbed by Top10/pBATGst, and 80% of the bounded Hg2+ could be desorbed from bacterial cells when pH was adjusted to 6.0. Thus, Top10/pBATGst can be potentially used for efficient treatment of Hg2+-contaminated aquatic environment. (C) 2013 Elsevier B.V. All rights reserved

    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    We 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
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