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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
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
Pharmacokinetic herb-drug interaction study of selected traditional medicines used as complementary and alternative medicine (CAM) for HIV/AIDS
Get PDFThesis (DMed)--Stellenbosch University, 2015ENGLISH ABSTRACT: Introduction
The increasing intake of traditional medicines among HIV/AIDS patients in sub-Saharan Africa needs urgent consideration by clinicians and other healthcare providers since the safety of such medications are unknown. The pharmacokinetic parameters - Absorption, Distribution, Metabolism and Elimination (ADME) play important role in the safety evaluation of drugs, thus implicating drug metabolizing enzymes and transporters as critical indicators for herb-drug interactions. The objective of this study was to evaluate the risk potential of seven herbal medicines commonly consumed by HIV/AIDS patients for drug interactions applying in vitro models. In this study, inhibition and induction effects of the herbal medicines on cytochrome P450s (CYPs) 1A2, 2C9, 2C19, 2D6 and 3A4 as well as P-glycoprotein (P-gp) were investigated.
Methods
Herbal medicines – Lessertia frutescens, Hypoxis hemerocallidea, Kalanchoe integra and Taraxacum officinale were sourced from Medico Herbs, South Africa were identified by experts from Compton Herbarium, South African National Biodiversity Institute, Cape Town. Moringa oleifera, Echinacea purpurea and Kalanchoe crenata were obtained from the repository of the National Centre for Natural Product Research (NCNPR), University of Mississippi, USA. Reversible inhibitory effect of aqueous and methanol herbal extracts were evaluated in recombinant CYPs applying the fluorescent metabolites at specified excitation/emission wavelengths; CYP1A2 (3-cyano-7-hydroxycoumarin (CHC); 405/460 nm), CYP2C9, CYP2C19 and CYP3A4 (7-hydroxy-4-(trifluoromethyl)-coumarin (HFC); 405/535 nm) and CYP2D6 (7-hydroxy-4-(aminomethyl)-coumarin (HAMC); 390/460 nm). Comparative studies in human liver microsomes (HLM) and recombinant CYPs were conducted to investigate the inhibitory effect of methanol herbal extracts and fractions on 6β testosterone hydroxylation activity. Time dependent inhibitory (TDI) effect of the herbal extracts were evaluated applying the IC50 shift fold, normalized ratio and the NADPH-, time- and concentration-dependent approaches. Influence of herbal extracts on metabolic clearance of testosterone was assessed in both HLM and human hepatocytes. The effects of each herbal extract on expression of CYP1A2, CYP3A4 and MDR1 genes were evaluated in activated human pregnane X receptor (PXR) co-transfected HepG2 cells. Finally, the inhibitory effect of herbal extracts on P-gp was assessed using the calcein-acetoxymethyl ester (calcein-AM) uptake and the digoxin radiolabelled substrates in MDCKII-MDRI cells.
Results
The aqueous extracts of Moringa oleifera, Kalanchoe integra, Kalanchoe crenata, Echinacea purpurea and Lessertia frutescens demonstrated high risk of in vivo inhibition on CYPs 3A4 and 1A2 with Cmax/Ki >1.0. Methanol extracts of these herbal medicines also indicated potential risk of reversible drug interaction. The methanol extracts of M. oleifera, K. crenata and L. frutescens showed strong TDI effect on CYP3A4 with IC50 shift fold >1.5 and normalised ratio <0.7. Moringa oleifera intermediately reduced intrinsic clearance of testosterone in human hepatocytes (2 ≤ AUC ratio ≤ 5) when scaled up to humans. Methanol extracts of Echinacea purpurea up-regulated the expression of CYP1A2, CYP3A4 and MDR1 genes in activated PXR. Kalanchoe crenata and Echinacea purpurea indicated strong inhibition on P-gp by reducing transport of digoxin across hMDR1-MDCKII cell monolayer from basolateral to apical with IC50 values of 18.24 ± 2.52 μg/mL and 24.47 ± 4.97 μg/mL, respectively.
Conclusion
The herbal medicines especially M. oleifera, K. integra and E. purpurea have the potential to cause herb-drug interaction in vivo if sufficient hepatic concentration is achieved in humans.AFRIKAANSE OPSOMMING: Inleiding
Die verhoogde inname van tradisionele medisynes onder MIV/VIGS-pasiënte in sub-Sahara-Afrika verg dringend oorweging deur klinici en ander gesondheidsorgverskaffers, aangesien die veiligheid van sodanige medikasies onbekend is. Die farmakokinetiese parameters – Absorpsie, Distribusie, Metabolisme en Eliminasie (ADME) – speel ’n belangrike rol by die veiligheidsevaluering van geneesmiddels, en impliseer gevolglik geneesmiddel-metaboliserende ensieme en vervoerders as kritiese indikators vir krui-geneesmiddel-interaksies (HDI). Die oogmerk van hierdie studie is om die risikopotensiaal van sewe kruiemedisynes wat algemeen deur MIV/VIGS-pasiënte geneem word, vir geneesmiddel-interaksies te evalueer deur in vitro-modelle te gebruik. In hierdie studie is die inhiberings- en induseringsuitwerkings van die kruiemedisynes op sitochroom P450’s (verkort na CYP’s) 1A2, 2C9, 2C19, 2D6 en 3A4, sowel as P-glikoproteïen (P-gp), ondersoek.
Metodes
Kruiemedisynes – Lessertia frutescens, Hypoxis hemerocallidea, Kalanchoe integra en Taraxacum officinale – is van Medico Herbs, Suid-Afrika, bekom en deur kundiges van die Compton-herbarium, by die Suid-Afrikaanse Nasionale Biodiversiteitsinstituut, Kaapstad, geïdentifiseer. Moringa oleifera, Echinacea purpurea en Kalanchoe crenata is van die bewaarplek van die Nasionale Sentrum vir Natuurlike Produknavorsing (NCNPR) aan die Universiteit van Mississippi in die VSA verkry. Die omkeerbare inhiberende uitwerking van kruie-ekstrakte in water en metanol is in rekombinante CYP’s geëvalueer deur die gebruik van die fluoresserende metaboliete op gespesifiseerde opwekkings-/emissiegolflengtes; CYP1A2 (3-siaan-7-hidroksikumarien (CHC); 405/460 nm), CYP2C9, CYP2C19 en CYP3A4 (7-hidroksi-4-(trifluoormetiel)-kumarien (HFC); 405/535 nm) en CYP2D6 (7-hidroksi-4-(aminometiel)-kumarien (HAMC); 390/460 nm). Vergelykende studies van menslikelewermikrosome (HLM) en rekombinante CYP’s is uitgevoer om die inhiberende uitwerking van metanolkruie-ekstrakte en -fraksies op 6β-testosteroonhidroksileringsaktiwiteit te ondersoek. Die tydafhanklike inhiberende uitwerking (TDI) van die kruie-ekstrakte is geëvalueer deur gebruikmaking van die IC50-verskuiwingsvou-, die genormaliseerdeverhoudings- en die NADPH-, tyd- en konsentrasieafhanklike benaderings. Die invloed van kruie-ekstrakte op metaboliese testosteroonverheldering is in beide HLM en menslike hepatosiete geëvalueer. Die uitwerkings van elke kruie-ekstrak op die uitdrukking van CYP1A2-, CYP3A4- en MDR1-gene is in geaktiveerde menslike pregnaan-X-reseptor(PXR)-, ko-getransfekteerde HepG2-selle geëvalueer. Laastens is die inhiberende uitwerking van kruie-ekstrakte op P-gp geëvalueer, met gebruikmaking van die kalsien-asetoksimetiel-ester (kalsien-AM)-opname en die digoksien- radiogemerkte substrate in MDCKII-MDRI-selle.
Resultate
Die ekstrakte in water van M. oleifera, K. integra, K. crenata, E. purpurea en L. frutescens het ’n hoë risiko van in vivo-inhibering op CYP’s 3A4 en 1A2 met Cmaks/Ki >1.0 getoon. Ekstrakte van hierdie kruiemedisynes in metanol het verder potensiële risiko van omkeerbare geneesmiddelinteraksie getoon. Die ekstrakte van M. oleifera, K. crenata en L. frutescens in metanol het sterk TDI-uitwerking op CYP3A4 met IC50-verskuiwingsvou >1.5 en genormaliseerde verhouding <0.7 getoon. M. oleifera het intermediêre vermindering van intrinsieke testosteroonverheldering in menslike hepatosiete (2 ≤ AUC verhouding ≤ 5) tot gevolg wanneer die skaal na mense verhoog word. Ekstrakte van E. purpurea in metanol het die uitdrukking van CYP1A2-, CYP3A4- en MDR1-gene in geaktiveerde PXR opgereguleer. K. crenata en E. purpurea het sterk inhibering van P-gp getoon deur die vervoer van digoksien deur die hMDR1-MDCKII-selmonolaag van basolateraal tot apikaal met IC50-waardes van onderskeidelik 18.24 ± 2.52 μg/mL en 24.47 ± 4.97 μg/mL te verminder.
Gevolgtrekking
Kruiemedisynes, veral M. oleifera, K. integra en E. purpurea, het die potensiaal om HDI in vivo te veroorsaak indien voldoende hepatiese konsentrasie by mense bereik word.Doctora
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn 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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