1,721,003 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Full text linkWe 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
Description of the interface between bitumen and mineral aggregates in respect to adhesive behaviour
No full textDas Ziel der Arbeit war es, einen Überblick über verschiedene analytische Techniken in Hinblick auf ihre Fähigkeit zu bieten, die Qualität eines Bitumens im Straßenbau vorab zu bestimmen. Viele der wichtigsten physikalischen Analysemethoden wurden angewendet um Informationen über Bitumen und das verwendete Gestein zu gewinnen und so auf die Adhäsion zwischen den Komponenten rückschließen zu können.Asphalt ist ein sehr gefragter, stark beanspruchter Werkstoff, dem im modernen Straßenbau eine besonders wichtige Rolle zukommt. Asphalt ist im wesentlichen ein Verbundwerkstoff aus Bitumen und verschiedenen mineralischen Bestandteilen. Die Anforderungen an den Werkstoff Asphalt steigen täglich, wodurch es für die Industrie dramatisch an Bedeutung gewinnt, neue Möglichkeiten der Qualitätskontrolle zu finden, um die Eigenschaften von Asphalt, der aus einem bestimmten Bitumen mit bestimmten mineralischen Bestandteilen hergestellt wird, gewährleisten zu können. Die tatsächliche Wechseslwirkung ist durch die chemische Komplexität des Bitumens kaum direkt erfassbar. Daher ist es notwendig, die jeweiligen Komponenten getrennt zu untersuchen. Die Untersuchung von Bitumen stellt dabei die größte Herausforderung dar. Während die rheologischen Eigenschaften von Bitumen noch relativ einfach zugänglich sind, ist die Voraussage chemischer oder physikalischer Interaktionen mit den Mineralien kaum möglich. Dazu wurden folgende Techniken verwendet: CLSM (konfokale Laser Mikroskopie), Fluoreszenzspektroskopie, IR-Spektroskopie, XRD (Röntgendiffraktion), Stickstoff-Adsorption, SEM (Scanning Electron Microscopy) und KontaktwinkelmessungenThe aim of this study is to provide an overview about analytical methods and their usability in the prediction of asphalt concrete quality. The most prominent analytical methods were used on the bitumen and the mineral aggregates to obtain various kinds of information about the adhesion inside the composite.Asphalt concrete is a high in demand material that plays the key role in modern roadworks. Asphalt concrete is a mixture of bitumen and different mineral aggregates. The interactions between these components are very complex and difficult to access. Hence, it is necessary to study the single components first before examining the composite: Bitumen is the key ingredient of asphalt concrete. Rheological and adhesive properties are important for the application in roadworks.While these are relatively easy to assess, it is very difficult to predict the adhesion between mineral aggregates and bitumen and thus the durability of the road. Since the traffic levels in the European Union are rising year by year, the stressing of the streets is increasing too.It has thus become essential for the petrol industry to provide defined high quality product. Bitumen is a colourful mixture of many different kinds of hydrocarbons, be they aliphatic, olefinic, aromatic, heteroaromatic, or condensed polyaromatic systems of huge proportions.Different analytical methods were applied successfully:Confocal laser scanning microscopy, Fluorescence spectroscopy, Infrared spectroscopy, X-ray photoelectron spectroscopy, Nitrogen adsorption, X-ray diffraction, Scanning electron microscopy, Confocal laser scanning microscopy, Contact angle measuremen
Unraveling the bitumen microstructure - towards a new understanding of bitumen ageing
No full textUnderstanding a materials microstructure is a vital and necessary premise to comprehend the ageing and corrosion of the very same. As the bitumen microstructure is much debated and unravelling its basic principles a keystone when looking at asphalt recycling, it became the first focal point of this study. By use of CLSM and AFM imaging, the microstructure was visualized in very high quality. The similar size of the phenomena indicates that identity or at least a strong linkage between the two can reasonably be assumed. Complementary use of fluorescence spectroscopy allowed the identification of the fluorescent centres visible in the CLSM images as the aromatics phase. These findings are incorporated into the modern micelle image, which is based on the agglomeration tendencies of asphaltenes proven beyond doubt, to create a new model of ageing. This new model is perfectly capable to explain the impact of short- and long-term ageing on the microstructure as well as "thermal healing" of asphalt by identifying the embrittlement of bitumen as a diffusion problem of polar oxidation products into the inner core of the micelle. Additionally, the laboratory ageing methods and field ageing were studied on carefully selected and unique samples. Those samples include seven to twenty-four year old roadwork not disturbed by maintenance or reconstruction, as well as a sample from a three year old highway already exhibiting strong signs of material failure. Partially, also the virgin binder was preserved in sealed metal cans, providing an original and un-oxidized sample for chemical and spectral investigation. Methods were investigated for their compliance with field ageing and it was found that they are generally in good accordance with the field samples, except for the influence of UV-radiation on SBS degradation in wear course
The pro-inflammatory cytokine IL6 and its negative regulator SOCS3 in androgen-sensitive prostate cancer
No full textProstatakrebs ist eine der häufigsten Krebserkrankungen bei Männern. Bei lokalisiertem Prostatakrebs ist eine Heilung möglich, allerdings führen bei fortgeschrittenem Prostatakrebs alle Therapien letztendlich zur Entwicklung einer Resistenz. Daher sind neue Behandlungsstrategien für fortgeschrittenen Prostatakrebs dringend notwendig. Derzeit ist die erste Wahl bei der Behandlung von fortgeschrittenem Prostatakrebs die Androgenentzugtherapie durch chirurgische oder hormonelle Kastration. Obwohl diese Therapie anfangs sehr erfolgreich darin ist die Tumorlast zu reduzieren, kommt es in nahezu allen Patienten zur Entwicklung eines kastrationsresistentem Zustand innerhalb von 3 Jahren. Das pro-inflammatorische Zytokin IL6 steht im Verdacht am Fortschreiten zum kastrationsresistenten Zustand beteiligt zu sein und weiters korreliert IL6 mit einer negativen Prognose. Daher war es das Ziel dieser Arbeit den IL6 Signalweg, und vor allem seinen negativ Regulator SOCS3, im Rahmen der Androgenentzugtherapie zu untersuchen.
SOCS3 ist ein IL6 induzierter negativer Rückkopplungs Regulator des IL6/JAK/ STAT3 Signalwegs. SOCS3 ist häufig durch Promotor-Hypermethylierung in verschiedenen Tumoren, einschließlich Prostatakrebs, inaktiviert. Hypermethylierung von SOCS3 konnte mit ansteigenden Gleason-Score und Tumorstadium korreliert werden. Knock-down von SOCS3 führte zu einer verstärkten IL6 Signalweiterleitung in einer Androgen-Rezeptor positiven Prostatakrebs-Zelllinie. Interessanterweise wird SOCS3 durch Anti-Androgene verstärkt exprimiert, was durch eine direkte transkriptionelle Regulation von Schlüsselelementen des IL6-Rezeptor-Komplex durch den Androgen-Rezeptor verursacht wird. Funktionell führte der knock-down von SOCS3 zu einer verstärkten Androgen-Rezeptor Aktivität nach 3 Wochen Enzalutamid Behandlung in Anwesenheit von inflammatorischen Zytokinen. Darüber hinaus wurden die Stammzell- und Selbsterneuerungs-assoziierten Gene SOX2 und NANOG durch die Langzeit-Behandlung stark hochreguliert, was durch die Modulierung von SOCS3 verhindert werden konnte. Diese Ergebnisse beweisen, dass SOCS3 eine wichtige Rolle bei der Anti-Androgen Behandlung in einer entzündlichen Umgebung spielt.
Außerdem untersuchten wir die differentielle Genexpression in AR positiven Prostata\-krebs-Zelllinien in Reaktion auf IL6. Wir konnten IRF9 als eines der am signifikantesten IL6 hochregulierten Gene identifizieren. Die IRF9 Proteinexpression in Prostatakrebs Gewebe ist sehr heterogen und ist mit IL6 korreliert. Außerdem konnten wir zeigen, dass die Expression von IRF9 essentiell ist um die anti-proliferative Wirkung von IFNa2 zu vermitteln. Diese Ergebnisse zeigen, dass zukünftige klinische Studien mit IFNa2 auf Patienten mit hohem IL6 Niveau begrenzt werden sollten.Prostate cancer is one of the most frequent malignancies in men. Curative treatment of localized prostate cancer is very successful, however, all therapies for advanced prostate cancer eventually lead to development of a resistance. Thus, novel treatment strategies for advanced prostate cancer are needed. Currently, first line treatment for advanced prostate cancer is androgen deprivation therapy by surgical or hormonal castration. Although initially successful in reducing tumour burden, nearly all patients progress to a castration resistant state within 3 years. The pro-inflammatory cytokine IL6 has been implicated in the progression to castration resistance and is associated with bad prognosis. Therefore, it was the aim of this thesis to investigate IL6 signalling and especially its negative regulator SOCS3 in the context of androgen deprivation.
SOCS3 is an IL6-induced negative feedback regulator of the IL6/JAK/STAT3 pathway, which is frequently inactivated by promoter hypermethylation in various tumours, including prostate cancer. Hypermethylation was found to be correlated with increasing Gleason score and tumour stage. Knock-down of SOCS3 led to enhanced IL6 signalling in an androgen receptor positive prostate cancer cell line. Interestingly, SOCS3 is upregulated by anti-androgens, which is caused by a direct transcriptional regulation of key elements of the IL6 receptor complex by the androgen receptor. Functionally, knock-down of SOCS3 led to enhanced androgen receptor activity after 3 weeks of enzalutamide treatment in an inflammatory setting. Furthermore, the stemness/self-renewal associated genes SOX2 and NANOG were strongly upregulated by the long-term treatment, and modulation of SOCS3 expression was sufficient to counteract this effect. These findings prove that SOCS3 plays an important role during anti-androgen treatment in an inflammatory environment.
Moreover, we investigated the differential gene expression in AR positive prostate cancer cell lines in response to IL6. We identified IRF9 as one of the most significantly upregulated genes in response to IL6 treatment. IRF9 protein expression in prostate cancer tissue was found to be heterogeneous and correlated to IL6 expression. Additionally, we could demonstrate that IRF9 expression is essential for IFNa2 to mediate its anti-proliferative effect. These findings demonstrate that future clinical trials with IFNa2 should be restricted to patients with high IL6 levels.Florian Handle, MScKumulative Dissertation aus vier ArtikelnZusammenfassung in deutscher SpracheDissertation Medical University of Innsbruck 201
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
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