1,721,035 research outputs found
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
Synthesis and self-assembly of DNA-β turn Conjugates
Get PDFThis thesis discusses the synthesis and self-assembly of several DNA-peptide conjugates, through different bi-orthogonal conjugating methods. Chapter 1 explores the current literature and perspective for which this work is based. Chapter 2 discusses the synthesis of DNA by solid phase synthesis, before being modified with a maleimide based phosphoramidite. The chapter goes on to discuss the development of these methods. Commercially bought DNA was modified with two bi-functional crosslinkers, before being further modified with different peptides. The chapter discusses the full scale of method development to obtain DNA-peptide conjugates, including the first known example of DNA β turn conjugates in the literature.
Chapters 3-5 discusses the self-assembly of DNA-peptide conjugates, with peptide directed, DNA and peptide directed, and DNA directed self-assembly respectively. Chapter 3, peptide driven assembly is explored through the doping of the parent peptide ILVAGK with varying amounts of DNA-ILVAGK. These experiments were observed over 28 days, and the resultant structures analysed by atomic force microscopy. In Chapter 4, both peptide and DNA driven self-assembly of DNA-ILVAGK is studied through DNA hybridisation with complementary sequences of 1, 2, and 3 lengths. As in Chapter 3, these studies were supported by atomic force microscopy, dynamic light scattering and circular dichroism. The structures observed in Chapter 4 differed in timeline and type to those seen in Chapter 3. Chapter 5 investigates DNA driven self-assembly with the peptide assembly disabled using sodium dodecyl sulphate. The structures observed during 28 days of aging showed little change in morphology over the period. This is indicative of the presence of hierarchy within this system.
Chapter 6 consists of an overall conclusion, to draw together the individual conclusions drawn in each chapter
Synthesis and Characterisation of Peptide-Oligonucleotide Conjugates Derived from β-sheet Forming or Collagen Mimetic Peptides
Get PDFAppropriate 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
Gold Nanoparticles as Adjuncts in Electrophoretic Analysis of Biopolymers
Get PDFThis thesis discusses two projects which investigate the analysis and application of biomolecules. Chapter 1 provides the background and context of this work. Chapter 2 discusses the synthesis and characterisation of three types of gold nanoparticles, sodium citrate, cetyltrimethyl ammonium bromide (CTAB) and 4-dimethylamino pyridine (DMAP) protected gold nanoparticles, as well as two types of polyacrylamide gel, TBE and tris-HCl. Successful characterisation of these gold nanoparticles was carried out by dynamic light scattering, ultra-violet visible spectroscopy and transmission emission microscopy. The characterisation of polyacrylamide gels was achieved by investigation by rheology, optical coherence tomography and scanning electron microscopy. Rheological analysis demonstrated that the addition of gold nanoparticles to polyacrylamide reduces the elasticity of the gel but stabilises the linear viscoelastic range, while not changing the core properties of the material. These materials were then used to separate sulfur containing biomolecules by polyacrylamide gel electrophoresis.
Chapter 3 discusses the efficacy of the three types of gold nanoparticles to separate sulfur containing biomolecules when added to polyacrylamide gel electrophoresis. Citrate and CTAB gold nanoparticles where unsuccessful when used to analyse phosphorothioated DNA, however, DMAP gold nanoparticles showed promising results. DMAP gold nanoparticles were further tested with the proteins lysozyme, bovine serum albumin (BSA), glutathione-S-transferase (GST) and RNAse A (RNAse). The retention of BSA and GST was successful however there was continued problems with visualising lysozyme and RNAse. This led to the development of ATP polyacrylamide gel electrophoresis.
Chapter 4 discusses the theoretical application of the development of catalytic DNA aptamers using in vitro selection. We synthesised a DNA aptamer library, two primers and two biotinylated strands of DNA, to be used in the selection process. However due to poor purity and yields, the project remains in its infancy. We discuss the methods by which we would conduct this research and our justifications for these processes
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
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