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    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

    Enzyme-responsive nanomaterials for the delivery of antimicrobial peptides

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    The rate of resistance to antibiotics that are commonly used in the clinic is escalating rapidly, surpassing the introduction of new antimicrobial drugs. To address this problem, alternative strategies are being explored, such as the re-evaluation of antibiotics, that have not yet gained widespread clinical application. Antimicrobial peptides (AMPs) represent one of those antibiotics, offering remarkable antimicrobial efficacy against various pathogens. However, in clinical settings, AMPs are typically considered a last-resort option due to their off-target effects and poor stability in-vivo resulting from their cationic and amphiphilic peptide nature. Therefore, most of current strategies addressing these limitations focus primarily on the control and shielding of the cationic charge and the amphiphilic nature of AMPs. These can potentially be achieved through encapsulation of AMPs inside stimuli-responsive polyelectrolyte complexes (PECs) by combining the cationic drug with anionic polyelectrolytes. Stimuli-responsive polymers can be employed as encapsulation materials in PECs to design systems that activate drug release in response to specific changes encountered during microbial infection, such as variations in pH, enzyme activity, or temperature. The overarching aim of this Thesis was to explore the creation of PECs capable of encapsulating the clinically approved antimicrobial peptide, Polymyxin B and its subsequent enzyme-induced release. In Chapters 2 and 3, the aims were: Firstly, to synthesize anionic and helical polymers incorporating enzyme-degradable peptide side chains (Aim 1.1), followed by evaluation of the degradation properties of these polymers in response to the enzyme released by gram-negative bacterium Pseudomonas aeruginosa (Aim 1.2). In Chapter 4, the first objective (Aim 1.3) was to assemble Polymyxin B and the anionic enzyme-degradable polymers into PECs. The next objective (Aim 1.4 ) involved investigating the P. aeruginosa-induced drug release from these PECs, while Aim 1.5 focused on assessing the antimicrobial activity of the developed PECs against P. aeruginosa strains. Chapter 1 provides a review of the current developments in the field of the stimuli- responsive delivery of AMPs using polyelectrolyte complexes. Chapters 2 and 3 discuss the synthesis of polymers with poly(methacrylamide) and poly(acetylene) backbones respectively coupled to enzyme-degradable peptide side chains. Of the synthesized materials, two poly(methacrylamide) polymers from Chapter 2 were found to be the most effective in terms of degradation by the enzyme released by P.aeruginosa, while none of the synthesized acetylene-containing peptides from Chapter 3 polymerized. Subsequently, the poly(methacrylamide) polymer with the highest multivalency was used to form PECs with Polymyxin B in Chapter 4. Eight different formulations of PECs were created, with one being the most optimized in terms of encapsulation efficacy and physiological stability. The stability of the particles was further improved by the addition of Tannic Acid, which acted as a protective coating and a cross-linker. The Thesis then evaluated the ability of the PECs to release Polymyxin B under enzymatic degradation. Finally, the preliminary evaluation of the antimicrobial activity of the PECs against various P.aeruginosa strains were presented

    Enzyme-responsive nanomaterials for the delivery of antimicrobial peptides

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    Completed under a Cotutelle arrangement between the University of Melbourne and University of Birmingham© 2024 Alexander AntropenkoThe rate of resistance to antibiotics that are commonly used in the clinic is escalating rapidly, surpassing the introduction of new antimicrobial drugs. To address this problem, alternative strategies are being explored, such as the re-evaluation of antibiotics, that have not yet gained widespread clinical application. Antimicrobial peptides (AMPs) represent one of those antibiotics, offering remarkable antimicrobial efficacy against various pathogens. However, in clinical settings, AMPs are typically considered a last-resort option due to their off-target effects and poor stability in-vivo resulting from their cationic and amphiphilic peptide nature. Therefore, most of current strategies addressing these limitations focus primarily on the control and shielding of the cationic charge and the amphiphilic nature of AMPs. These can potentially be achieved through encapsulation of AMPs inside stimuli-responsive polyelectrolyte complexes (PECs) by combining the cationic drug with anionic polyelectrolytes. Stimuli-responsive polymers can be employed as encapsulation materials in PECs to design systems that activate drug release in response to specific changes encountered during microbial infection, such as variations in pH, enzyme activity, or temperature. The overarching aim of this Thesis was to explore the creation of PECs capable of encapsulating the clinically approved antimicrobial peptide, Polymyxin B and its subsequent enzyme-induced release. In Chapters 2 and 3, the aims were: Firstly, to synthesize anionic and helical polymers incorporating enzyme-degradable peptide side chains (Aim 1.1), followed by evaluation of the degradation properties of these polymers in response to the enzyme released by gram-negative bacterium Pseudomonas aeruginosa (Aim 1.2). In Chapter 4, the first objective (Aim 1.3) was to assemble Polymyxin B and the anionic enzyme-degradable polymers into PECs. The next objective (Aim 1.4 ) involved investigating the P. aeruginosa-induced drug release from these PECs, while Aim 1.5 focused on assessing the antimicrobial activity of the developed PECs against P. aeruginosa strains. Chapter 1 provides a review of the current developments in the field of the stimuli- responsive delivery of AMPs using polyelectrolyte complexes. Chapters 2 and 3 discuss the synthesis of polymers with poly(methacrylamide) and poly(acetylene) backbones respectively coupled to enzyme-degradable peptide side chains. Of the synthesized materials, two poly(methacrylamide) polymers from Chapter 2 were found to be the most effective in terms of degradation by the enzyme released by P.aeruginosa, while none of the synthesized acetylene-containing peptides from Chapter 3 polymerized. Subsequently, the poly(methacrylamide) polymer with the highest multivalency was used to form PECs with Polymyxin B in Chapter 4. Eight different formulations of PECs were created, with one being the most optimized in terms of encapsulation efficacy and physiological stability. The stability of the particles was further improved by the addition of Tannic Acid, which acted as a protective coating and a cross-linker. The Thesis then evaluated the ability of the PECs to release Polymyxin B under enzymatic degradation. Finally, the preliminary evaluation of the antimicrobial activity of the PECs against various P.aeruginosa strains were presented

    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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    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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