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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
Renale Denervation reduziert die myokardiale Expression von Pattern Recognition Receptors sowie die Plasma-Konzentration des Urämietoxins Indoxylsulfat und hemmt die Entstehung einer linksventrikulären Hypertrophie in einem Rattenmodell der chronischen Nierenerkrankung
No full textHintergrund:
Die chronische Nierenerkrankung (CKD) stellt einen unabhängigen Risikofaktor für kardiovaskuläre Komplikationen dar. CKD-Patienten entwickeln eine urämische Kardiomyopathie, die durch linksventrikuläre Hypertrophie (LVH), Fibrose und Anfälligkeit für Arrhythmien charakterisiert ist. Zudem ist CKD mit einer erhöhten Aktivität des sympathischen Nervensystems (SNS) assoziiert. Die renale Denervation (RDN) ist ein Verfahren zur Modulation renaler sympathischer Fasern durch Hochfrequenzstrom oder Ultraschallenergie. RDN stellt heutzutage eine minimalinvasive Therapieoption zur Behandlung der arteriellen Hypertonie dar. Ferner kann nach RDN eine Reduktion der LVH beobachtet werden. In der Genese der urämischen Kardiomyopathie spielen Urämietoxine, insbesondere Indoxylsulfat (IS), eine entscheidende Rolle. Des Weiteren tragen sogenannte Pattern Recognition Rezeptoren (PRRs) zur myokardialen Inflammation bei CKD bei. Inwiefern RDN die Entstehung einer urämischen Kardiomyopathie beeinflusst, ist unklar. Das Ziel dieser Arbeit ist es, anhand eines Rattenmodells der CKD den Einfluss der RDN auf die Entstehung der urämischen Kardiomyopathie zu untersuchen. Ferner wird untersucht, inwiefern RDN einen Einfluss auf den renalen Phänotyp in diesem Rat-
tenmodell hat.
Methoden:
Männliche Sprague-Dawley-Ratten erhielten über einen Zeitraum von 16 Wochen entweder eine Standarddiät (CTRL, n = 4) oder eine 0,25 %-haltige Adenin-Diät, um eine CKD zu induzieren (AD, n = 10). Nach 4 Wochen erfolgte bei AD eine Randomisierung in eine sham-Gruppe (AD, n = 5) und eine Interventionsgruppe (AD-RDN, n = 5), welche renal denerviert wurden. RDN erfolgte chemisch mittels Betupfens der Adventitia der Nierenarterien mit einer Phenol/Ethanol-Lösung. AD und CTRL erhielten jeweils eine sham-Prozedur. Nach 16 Wochen wurden die Tiere getötet und Organe für weitere Untersuchungen entnommen. Das Ausmaß der LVH wurde durch Echokardiographie, Kardio-MRT und histologische Analysen untersucht. Die Messung der Konzentrationen des Urämietoxins IS im Plasma, der Niere und der Leber erfolgte durch ELISA. Western Blot Analysen dienten der Bestimmung der Expression der PRRs RAGE, TLR2 und TLR4 sowie des Liganden HMGB1 im Myokard und der Niere. Die erfolgreiche RDN wurde durch Messung der Noradrenalin-Konzentration in den Nieren bestätigt. In-vitro-Experimente mit H9c2-Zellen wurden durchgeführt, um die pro-hypertrophen Effekte von IS und den Einfluss des Decoy-Rezeptors sRAGE zu untersuchen. Die Zellhypertrophie wurde mittels Forward Scatter der FACS-Analyse bestimmt.
Ergebnisse:
Bei AD war die LV Wanddicke (LV Septumdicke, 2,36 ± 0,032 mm vs. 1,92 ± 0,016 mm in CTRL, p < 0,0001) sowie die E/A-Ratio, ein Marker für die diastolische Funktion, sowie die Myozytenquerschnittsfläche im Vergleich zu CTRL erhöht. Nach RDN waren die LV Wanddicke (1,95 ± 0,05 mm, p < 0,0001 vs. AD), die E/A-Ratio (1,08 ± 0,04 vs. 1,93 ± 0,12 in AD, p < 0,0001) sowie die Myozentenquerschnittsfläche signifikant erniedrigt. Die Plasma Konzentration von IS war bei AD signifikant erhöht (0,7 ± 0,10 µg/ml vs. 0,2 ± 0,12 µg/ml in CTRL, p = 0,0044) und nach RDN verringert (0,28 ± 0,072 µg/ml, p = 0,0073 vs. AD). Die renale Ausscheidung von IS war nach RDN unverändert, während die hepatische Konzentration von IS nach RDN reduziert war (1,72 ± 0,09 µg/500 µg vs. 2,45 ± 0,21 µg/500µg in AD, p = 0,023). Es zeigte sich eine Korrelation zwischen der LVH und der Plasma-IS Konzentration (n=14, r=0,67, p = 0,008). Die Expression der kardialen PRRs zeigte lediglich bei RAGE eine Regulation (RAGE-Expression +266 % in AD vs. CTRL, p = 0,015; –88 % in AD-RDN vs. AD, p = 0,047). Myokardiales sRAGE wurde durch RDN erhöht (+433 % vs. AD, p = 0,013). Sowohl im Herzen als auch in der Niere ergab sich bei TLR2 und TLR4 keine Regulation. Die vorteilhaften Effekte der realen Denervation waren unabhängig vom Blutdruck und der Nierenfunktion.
Schlussfolgerungen:
RDN reduziert die Plasma-Konzentration von IS und verringert die LVH in einem Rattenmodell der CKD. Die geringere IS-Konzentration könnte auf eine geringere intestinale Resorption oder hepatische Bildung des Toxins zurückzuführen sein. RDN könnte eine sinnvolle Therapieoption bei Patienten mit CKD darstellen, um kardiovaskuläre Endpunkte zu reduzieren.Background:
Chronic kidney disease (CKD) is an independent risk factor for cardiovascular complications. CKD patients develop a uremic cardiomyopathy characterized by left ventricular hypertrophy (LVH), fibrosis and susceptibility for arrhythmias. Furthermore, CKD is associated with increased activity of the sympathetic nervous system (SNS). Renal denervation (RDN) is a method of ablating renal sympathetic nerve fibers using radiofrequency or ultrasound energy. Today, RDN represents a catheter-based therapeutic option for patients with hypertension. In addition, RDN has been shown to reduce LVH. Uremic toxins, above all Indoxyl sulfate (IS), play a key role in the development of uremic cardiomyopathy. Also, so-called pattern recognition receptors (PRRs) contribute to myocardial inflammation in CKD. It is unknown whether RDN influences the development of uremic cardiomyopathy. This study aimed at investigating the influence of RDN on uremic cardiomyopathy in a rat model of CKD. Furthermore, we analyzed whether RDN has any effects on renal parameters in this rat model.
Methods:
Over a period of 16 weeks, male Sprague-Dawley-Rats received either standard chow (CTRL, n=4) or a 0,25% adenine-containing diet to induce CKD (AD, n=10). After 4 weeks, AD were randomized to sham (AD, n=5) or RDN (AD-RDN, n=5). RDN was performed chemically using a phenol/ethanol solution. AD and CTRL were subjected to sham procedures. After 16 weeks, animals were sacrificed and organs were harvested for further analyses. LVH was assessed by echocardiography, cardiac MRI and by histological analysis. Plasma, hepatic and urinary concentrations of IS were measured by ELISA. Western blot analyses were used to determine the expression of the PRRs RAGE, TLR2 and TLR4 as well as their ligand HMGB1 in myocardium and kidney. Successful RDN was confirmed by measurement of norepinephrine in kidney tissue. In-vitro experiments using H9c2 cells were conducted to study the pro-hypertrophic effects of IS and the influence of the decoy-receptor sRAGE. Cell hypertrophy was estimated by forward scatter in FACS analysis.
Results:
In AD, LV wall thickness (LV septum thickness, 2.36±0.03mm vs. 1.92±0.02mm in CTRL, p<0.0001), E/A ratio, a marker of diastolic function as well as myocyte cross sectional area were increased compared with CTRL. After RDN, LV wall thickness (1.95±0.05mm, p<0.0001 vs. AD), E/A ratio (1.08±0.04 vs. 1.93±0.12 in AD, p<0.0001) as well as myocyte cross sectional area were significantly reduced. Plasma concentration of IS was significantly increased in AD (0.71±0.10µg/ml vs. 0.2±0.12µg/ml in CTRL, p=0.0044) and decreased in AD-RDN (0.28±0.072µg/ml, p=0.0073 vs. AD). Renal excretion of IS was unaltered by RDN, while hepatic concentration of IS was reduced after RDN (1.72±0.09 µg/500µg vs. 2.45±0.21µg/500µg in AD, p=0.023). LVH correlated significantly with plasma IS (n=14, r=0.67, p=0.008). Expression of cardiac PRRs showed regulation only with respect to RAGE (RAGE expression +266% in AD vs. CTRL, p=0.015; –88% in AD-RDN vs. AD, p=0.047). Myocardial sRAGE was increased by RDN (+433% vs. AD, p=0.013). TLR2 and TLR4 did not show any regulation both in the heart and kidney. The beneficial effects of RDN were independent of blood pressure decrease and renal function.
Conclusions:
RDN reduces plasma concentration of IS and improves LVH in a rat model of CKD. The decreased IS concentration may be due to decreased intestinal absorption or hepatic production of the toxin. RDN may represent a therapeutic option for patients with CKD to reduce cardiovascular outcomes
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
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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