1,720,961 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
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
Die Rolle von Natürlichen Killerzellen und Natürlichen Killer T-Zellen in der HCV Infektion
Get PDFWorldwide 71 million people are chronically infected with HCV and each year approximately 400 000 people die from HCV associated liver diseases. The most important risk factor in western industrialised countries to acquire HCV infection is intravenous drug use. For this reason, we utilised a cohort of people who inject drugs (PWID) to comparatively analyse PWID developing chronic infection (HCV RNA positive), spontaneously resolving HCV infection (HCV RNA negative) and PWID remaining anti HCV seronegative (anti HCV negative), to provide novel insights into the contribution of innate and adaptive immune mechanisms to HCV infection outcome.
The role of Natural Killer T (NKT) cells, which share characteristics of innate and adaptive immune cells, for the outcome of HCV infection is poorly defined. Invariant NKT (iNKT) cells, a subset of NKT cells, recognise glycolipid antigens such as α galactosylceramide (αGalCer) presented by the non-classical MHC molecule CD1d. Decreased iNKT cell frequencies have been reported in chronically HCV infected patients, however, contradicting reports exist. In this study iNKT cell frequencies did not differ between HCV RNA positive (n=28) and HCV RNA negative (n=33) PWID. Interestingly, phenotypic analysis of iNKT cells of chronically infected PWID showed significantly higher expression of the activation marker CD38, however, this was not associated with apparent differences in PMA/ionomycin stimulated effector functions. In addition, treatment with a combination of IL12, -15 and -18, which is described to activate NK cells, led to a significant increase in CD38+ iNKT cells. Since IFN stimulated genes are induced in patients with chronic infection the influence of IFNs on iNKT cell activation was addressed as well. Although no direct effect of IFNα on iNKT cell activation was observed, CD1d was upregulated on peripheral monocytes, the cell type with the highest expression of CD1d in the periphery. However, CD1d levels on monocytes, did not differ between PWID with chronic and resolved HCV infection. Nevertheless, presence of monocytes promoted iNKT cell expansion and activation, as depletion of monocytes significantly reduced the frequency of CD38+ iNKT cells. Furthermore, CD1d transcript levels were significantly higher in HCV infected liver compared to HBV-infected liver. Collectively the data demonstrate that iNKT cells are activated in chronically HCV infected PWID, possibly via type I interferon-induced upregulation of CD1d on monocytes or other liver resident cells or via direct activation by pro inflammatory cytokines. However, the functional consequences of increased activation of iNKT cells are not fully defined.
While iNKT cells are still poorly covered by scientific reports in HCV infection there is growing evidence for the importance of NK cells for HCV infection outcome. Genetic association studies revealed that specific genetically determined combinations of NK cell-receptors and their ligands are associated with differential outcome of HCV infection. NK cell function is regulated by a set of inhibitory and activating receptors including killer-cell immunoglobulin-like receptors (KIRs). A previous study in our lab identified that KIR3DL1/HLA-Bw4 80(T) was associated with spontaneous clearance of HCV infection in our PWID cohort (n=266) which was validated in a second PWID cohort from North America (n=342). For this reason, this study focused on the functional characterisation of NK cells according to the identified KIR/KIR-ligand genotype. Besides PWID, healthy individuals (n=120) were included in the analysis as well. KIR3DL1+ NK cells from HLA-Bw4 80(T) positive PWID showed superior functionality compared to HLA Bw4 80(I) positive PWID. However, this differential impact was not observed in healthy donors. Moreover, the frequency of individuals with multiple HLA-Bw4 alleles was significantly higher in HCV RNA negative as well as anti HCV negative PWID compared to HCV RNA positive PWID and HLA-Bw4 copy number strongly correlated with the functionality of KIR3DL1+ NK cells in healthy individuals. HLA-Bw4 80(T) and multiple HLA-Bw4 copies in combination with KIR3DL1 are associated with protection against chronic HCV in PWID by distinct mechanisms. Better education of KIR3DL1+ NK cells in the presence of multiple HLA Bw4 copies is beneficial prior to seroconversion whereas HLA Bw4 80(T) may be beneficial during acute hepatitis C. To determine possible underlying mechanisms leading to the superior functionality of KIR3DL1+ NK cells, the DNA methylation pattern of the IFNG locus was analysed, since demethylation of the IFNG locus is generally associated with increased IFNG transcription. Unfortunately, the significantly enhanced IFNγ capacity of KIR3DL1+ NK cells from multiple HLA Bw4 motif carriers was not epigenetically regulated by DNA methylation. However, our data could confirm that NK cell memory features, attributed to NKG2C expressing NK cells in CMV positive individuals, are epigenetically imprinted within the IFNG locus.
In summary, these studies contribute novel evidence for the importance of NK cells and iNKT cells for HCV infection outcome and describe possible underlying mechanisms. However, further research is needed to elucidate for instance, the role of HCV peptides presented by HLA alleles harbouring a Bw4 motif on the function of KIR3DL1+ NK cells or the exact mechanism leading to the activated state of iNKT cells during chronic HCV infection.Nach Schätzung der WHO sind zurzeit 71 Millionen Menschen weltweit chronisch mit dem Hepatis C Virus (HCV) infiziert und jährlich sterben etwa 400.000 Menschen an den Folgen einer HCV induzierten Leberkrankungen. In westlichen Industrieländern stellt der intravenöse Drogenkonsum hierbei den höchsten Risikofaktor dar, sich mit HCV zu infizieren. Um neue Erkenntnisse über die Rolle des natürlichen und angeboren Immunsystems in der HCV Infektion zu gewinnen, wurde einer Kohorte von intravenös Drogen gebrauchenden Menschen („people who inject drugs“ PWID) analysiert. Hierbei wurden PWID mit chronischer HCV-Infektion (HCV RNA positiv), ausgeheilter HCV-Infektion (HCV RNA negativ) und HCV seronegative PWID (anti HCV negativ) miteinander verglichen.
Welche Rolle Natürliche Killer T (NKT) Zellen, die sowohl Eigenschaften von innaten als auch adaptiven Immunzellen aufweisen, bei dem Verlauf einer HCV Infektion spielen ist nicht klar definiert. Invariante NKT (iNKT) Zellen stellen eine Subgruppe der NKT Zellen dar und erkennen Glycolipid Antigene wie z.B. α galactosylceramid (αGalCer), die durch das nicht klassische MHC Molekül CD1d präsentiert werden. Die Untersuchung der iNKT Zellfrequenzen zeigte keine Unterschiede zwischen HCV RNA positiven (n=28) und HCV RNA negativen (n=33) PWID. Interessanterweise ergab die phänotypische Analyse, dass sich iNKT Zellen von chronisch HCV infizierten PWID durch eine signifikant erhöhte Expression des Aktivierungsmarkers CD38 auszeichnen. Allerdings konnten keine funktionellen Unterschiede mit diesem aktivierten Phänotyp assoziiert werden. Zusätzlich wurde die Auswirkung von Interferonen auf iNKT Zellen in dieser Studie adressiert. Während kein direkter Effekt von IFNα oder IFNλ festgestellt werden konnte, führte eine Kombination von NK Zell aktivierenden Zytokinen (IL12, IL15 und IL18) zu einer signifikanten Erhöhung der CD38+ iNKT Zellen. Auch wenn gezeigt werden konnte, dass der Ligand von iNKT Zellen durch IFNα Stimulation hochreguliert wird, konnte kein Unterschied in der CD1d Expression auf peripheren Monozyten, welche in der Peripherie den Zelltyp mit der höchsten CD1d Expression darstellen, zwischen HCV RNA positiven und HCV RNA negativen PWID festgestellt werden. Dennoch nehmen Monozyten eine wichtige Rolle in der Expansion und Aktivierung von iNKT Zellen ein, da eine Depletierung selbiger eine signifikant verminderte Frequenz von CD38+ iNKT Zellen zur Folge hat. Des Weiteren ergaben Leberanalysen, dass HCV infizierte Lebern im Vergleich zu HBV infizierten Lebern eine signifikant erhöhte CD1d Transkription aufweisen. Zusammengefasst weisen unsere Daten darauf hin, dass iNKT Zellen in der chronischen HCV Infektion aktiviert sind. Sowohl eine Typ I Interferon induzierte Hochregulation von CD1d auf Monozyten oder anderen Zellen in der Leber als auch das proinflammatorische Zytokine Milieu sind potentiell für die Modulation des Aktivierungsstatus von iNKT Zellen in der HCV Infektion verantwortlich.
Während es kaum wissenschaftliche Berichte gibt, die sich mit iNKT Zellen im Kontext der HCV Infektion auseinandersetzen, steigt die Zahl an Belegen, die NK Zellen eine wichtige Bedeutung für die Prävention und Kontrolle einer HCV Infektion zusprechen. Verschiedene Assoziationsstudien konnten bereits zeigen, dass genetisch determinierten Kombinationen von NK Zell Rezeptoren und ihren Liganden mit der HCV Verlaufsprognose assoziiert sind. Die NK Zell Funktion wird durch aktivierende und inhibierende Rezeptoren einschließlich der Killerzell Immunglobulin ähnlichen Rezeptoren (KIR) reguliert. In einer vorangegangenen Studie wurde mit Hilfe einer multivariaten logistischen Regressionsanalyse KIR3DL1/HLA-Bw4 80(T) mit der spontanen Ausheilung einer HCV Infektion in unserer PWID Kohorte (n=266) assoziiert. Diese Assoziation konnte in einer zweiten anti HCV positiven PWID Kohorte (n=342) aus Nordamerika validiert werden. Auf Grund dessen wurden in der vorliegenden Studie NK Zellen anhand ihres KIR/KIR Liganden Genotyps funktionell charakterisiert. Neben PWID wurden auch gesunde Proben (n=120) in der Analyse inkludiert. Es konnte gezeigt werden, dass KIR3DL1+ NK Zellen von HLA-Bw4 80(T) positiven PWID verglichen mit HLA Bw4 80(I) positiven PWID eine signifikant erhöhte NK Zell Funktionalität aufweisen. Hingegen konnte kein funktioneller Einfluss dieses Genotyps in gesunden Individuen beobachtet werden. Darüber hinaus wurde gezeigt, dass multiple HLA Bw4 Allele, deren Frequenz signifikant in HCV RNA negativen und anti HCV negativen PWID im Vergleich zu HCV RNA positiven PWID erhöht ist, auch mit einer starken NK Zell Funktionalität einhergehen. Zusammenfassend können sowohl HLA Bw4 80(T) als auch multiple Kopien von HLA Bw4 in Kombination mit KIR3DL1 mit der Protektion gegen eine chronische Hepatitis C assoziiert werden. Diese wird über verschiedene Mechanismen vermittelt: während eine bessere NK Zell Lizensierung durch die Anwesenheit von multiplen HLA Bw4 Kopien vor der Serokonversion vorteilhaft ist, könnte HLA Bw4 80(T) während eine akuten HCV Infektion von Vorteil sein. Epigenetische Veränderung könnten eine mögliche Erklärung für die erhöhte IFNγ Produktion von KIR3DL1+ NK Zellen im Kontext von multiplen HLA Bw4 Allelen bieten. Hierfür wurde die DNA Demethylierung des IFNG Lokus, welche generell mit einer erhöhten Transkription assoziiert ist, analysiert. Es konnte jedoch kein Zusammenhang zwischen dem Methylierungsstatus und der Anzahl an HLA Bw4 Kopien hergestellt werden. Hingegen konnten vorausgegangene Studien bestätigt werden, die besagen, dass Memory Eigenschaften von NKG2C exprimierenden NK Zellen in CMV positiven Individuen epigenetisch reguliert sind.
Abschließend lässt sich feststellen, dass die hier präsentierten Studien neue Beweise für die Bedeutsamkeit von NK und iNKT Zellen für den HCV Infektionsverlauf liefern und Hinweise auf mögliche zugrundeliegende Mechanismen geben. Dennoch sind weitere Arbeiten notwendig die z.B. klären ob HCV Peptide, die durch Bw4 Motiv tragende HLA Allele präsentiert werden, einen Einfluss auf die Funktion von KIR3DL1+ NK Zellen haben oder welche Mechanismen genau während der chronischen Infektion zu einer Aktivierung von iNKT Zellen führen
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
- …
