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    Surface Functionalization of PLGA Nanoparticles with Hyaluronic Acid of Different Molecular Weight for Targeted Drug Delivery to Acute Kidney Injury

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    Acute kidney injury (AKI) is a severe renal condition characterized by an abrupt decline in kidney function. Poly(Lactide-co-Glycolide) (PLGA) is a well-known biocompatible polymer widely investigated for nanoparticle carrier systems; however, it faces challenges with non-specific distribution and AKI targeting. In this study, a targeted drug delivery system was developed by using functionalized PLGA nanoparticles with HA to enhance therapeutic delivery efficiency to injured kidneys overexpressing CD44. PLGA nanoparticles were synthesized using a double emulsion (W/O/W) method and subsequently functionalized with thiol groups via cysteamine conjugation. Maleimide-functionalized hyaluronic acid (HA-Mal) of varying molecular weights (200 kDa, 500 kDa, and 3 MDa) were synthesized and conjugated to the nanoparticles through a thiol-maleimide click reaction. Dynamic light scattering (DLS) and scanning electron microscopy (SEM) confirmed spherical morphology and increased hydrodynamic size post-functionalization. Angiotensin 1-7, a therapeutic peptide with anti-inflammatory and renoprotective properties, was encapsulated within the nanoparticles, exhibiting sustained release profiles and high encapsulation efficiency. Cellular uptake studies validated the selectivity of HA-coated nanoparticles for CD44-overexpressing cells. These findings demonstrate the potential of HA-functionalized PLGA nanoparticles as a kidney-specific drug delivery platform, providing a promising approach to enhancing AKI treatment with minimized side effects.MasterAbstract i Contents ii List of Tables iv List of Figures iv Chapter 1. Introduction 1 1.1. Overview of acute kidney injury and therapeutic treatment 1 1.2. Polymeric nanoparticles in drug delivery and their limitations 1 1.3. Surface functionalization of PLGA nanoparticles for targeted delivery 2 1.4. CD44-Hyaluronic acid interactions 3 1.5. Experimental overview 4 Chapter 2. Materials and Methods 6 2.1. Materials 6 2.2. Methods 6 2.2.1. Synthesis of HA-Maleimide 6 2.2.2. Synthesis of PLGA nanoparticles 7 2.2.3. Introduction of thiol function on PLGA nanoparticles 7 2.2.4. HA-Maleimide coating on PLGA nanoparticles 7 2.2.5. Quantitative determination of thiol functions with Ellman's reagent 8 2.2.6. Characterization of HA-Maleimide 8 2.2.7. Physicochemical analysis of HA-PLGA-NPs 9 2.2.9. Drug loading and encapsulation efficiency 9 2.2.10. In vitro release of Ang 1-7 10 2.2.11. In vitro cytocompatibility test 10 2.2.12. Cellular uptake of NPs 11 Chapter 3. Results and Discussion 12 3.1. Synthesis and characterization of HA-Maleimide 12 3.2. Preparation and characterization of HA-PLGA NPs 14 3.3. Drug loading and encapsulation efficiency 19 3.4. In vitro Ang 1-7 release behaviors of NPs 20 3.5. In vitro cytocompatibility test 21 3.6. Cellular uptake of NPs 23 Chapter 4. Conclusion 26 References 2

    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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    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

    Author Under Sail The Imagination of Jack London, 1893-1902

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    In Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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