1,720,971 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
A cylindrical high-resolution intracranial implant for neural recording and stimulation
No full textDiese Arbeit befasst sich mit der Entwicklung, Charakterisierung und der In- Vivo-Validierung eines neuen, zylindrischen hochauflösenden intrakaniellen Implantats zur Aufzeichnung und Stimulation neuronaler Signale. Fokale Epilepsie wurde als klinisches Applikationsszenario herangezogen um grundlegende Anforderungen, wie Implantatgeometry, Implantationsdauer und aufzuzeichnende Signale, zu definieren. Von diesen Anforderungen ausgehend, werden dem Implantat weitere Funktionalitäten hinzugefügt, um die Spanne der möglichen Anwendungen zu erweitern. Die Spanne potentieller Anwendungen umfasst fundamentale neuronale Forschung und die Behandlung der Parkinson-Krankheit, Dystonie und Depression. Die hier gezeigte neuronale Sonde hat eine zehnfach höhere Anzahl an Elektroden pro Implantat, d.h. 128 Elektroden, als klinisch zugelassene Sonden. Dies ermöglicht das Aufzeichnen neuronaler Signale mit erhöhter Auflösung verglichen zum Stand der Technik. Des Weiteren ermöglicht die Sonde das Aufzeichnen von Aktionspotentialen einzelner Neurone. Dies ermöglicht bisher nur äußerst selten angewandte diagnostische Methoden für Epilepsie bei unerreichter Auflösung. Der in dieser Arbeit genutzte Herstellungsprozess verwendet fotolithografische Methoden in Kombination mit Polyimidsubstraten, um Platin-Leiterbahnen und -Elektroden mit Strukturgrößen ab 3 μm mikromechanisch zu strukturieren. Anschließend werden die Substrate durch Rollen innerhalb einer Metallform bei 300°C ausgehärtet und so in ihre zylindrische Sondenform gebracht. Eine zusätzliche Cytop-Schicht wird als Trockenkleber verwendet, um die Sondenform zu fixieren und den Umfang der Sonde zu verschließen. Das hohle innere Volumen der Sonde wird dazu genutzt, um LEDs für optogenetische Forschung als auch CMOS-Chips zum Zwecke des Multiplexings der gewonnenen Signale zu integrieren. Um die mechanische Stabilität der Sonde zu gewährleisten, wird anschließend der Rest der Sonde mit einem Epoxidharz gefüllt. Die Sonden werden über die Dauer von 100 Tagen mittels eines speziell angefertigten Impedanzspektrometers elektrisch charakterisiert. Während dieser Periode werden die Sonden 37°C warmer Ringerlösung ausgesetzt, um so die biologische Umgebung nachzuahmen. Dabei werden zunächst biologische Zersetzungsfaktoren außer Acht gelassen. Die Hälfte der Elektroden einer jeden Sonde werden mit 1000 Stimulationspulsen von 1 V Amplitude und 1 ms Dauer pro Stunde beaufschlagt. Dies dient als erste Evaluation für klinische Zwecke, bei denen elektrische Stimulation benötigt wird. In-vivo-Implantationen in Ratten und einem Affen zeigen, dass es möglich ist, über die Dauer von 10 Tagen stabil Aktionspotentiale aufzuzeichnen, welches die ungefähre Imlpantationsdauer für die Diagnose fokaler Epilepsie ist. Die längste nachgewiesene Dauer, nach der eine Sonde es noch erlaubt Aktionspotentiale auf zu zeichnen, ist 13 Wochen. Dies ist in Übereinstimmung mit den Ergebnissen der elektrischen Charakterisierungsmessungen in Ringerlösung und damit ein Hinweis, dass elektrochemische Prozesse die Zersetzung der Sonde beherrschen. Da die Elektrodenschicht nur 300 nm dünn ist, ist eine Hypothese, dass Sonden mit stärkerer Elektrodenschicht der Zersetzung länger Stand halten. Um diese Hypothese zu testen, wurden die Elektroden einer Sonde nach dem Rollprozess galvanisch mit Gold beschichtet und 37°C warmer Ringerlösung ausgesetzt. Die Impedanz der Elektroden hat sich über die gesamte Dauer von 30 Tagen nicht geändert. Daraus lässt sich schließen, dass Sonden mit zusätzlicher Elektrodenschicht, oder unterschiedlichem Material, dem Zersetzungsprozess standhalten können. Dies ebnet den Weg zu chronischen Implantationen mit Anwendungen, welche die Dauer von 10 Tagen überschreiten. Des Weiteren wird in dieser Arbeit ein thermomechanisches Model des verwendeten Polyimidsubstrats etabliert. Dieses Model erlaubt es, mechanische Restspannungen und Dehnungen des Polyimids zu berechnen, nachdem dieses machanischen Belastungen und Temperaturen zwischen 22°C und 300°C für Zeitdauern bis zu 24 Stunden ausgesetzt wurde.This thesis presents the development, characterization, and in-vivo validation of a novel cylindrical high-resolution intracranial implant for neural recording and stimulation. Focal epilepsy was taken as a clinical application scenario in order to define basic technical requirements, such as implant geometry, implantation duration, and necessary information to be acquired by the implant. To these basic requirements, additional functionality is added to improve this specific implant and broaden the range of possible applications. The potential application range spans from fundamental neural research to the treatment of Parkinson’s disease, dystonia, and depression. The presented neural probe has a tenfold increase of electrodes per device, i.e. 128 electrodes, in comparison with clinically approved devices. This enables the recording of neural signals at a higher resolution than by state-of-the-art devices. Furthermore, the electrodes allow recording of action potentials of single neurons. This enables the use of rarely used diagnostic methods for epilepsy at an unprecedented resolution. The fabrication process applied in this thesis makes use of photolithographic methods in combination with polyimide substrates to micromechanically structure platinum leads and electrodes down to 3 μm. Subsequently these substrates are brought into the cylindrical probe shape by rolling them inside a metallic mould and curing them at 300°C. An additional Cytop layer serves as a dry adhesive to retain the intended probe shape and seal its circumference. The inner volume of the probe is used to integrate LEDs for optogenetic research or to integrate CMOS chips for multiplexing the acquired multi-channel signals. Finally, to improve the mechanical stability of the entire probe, it is filled with an epoxy. The probes are electrically characterized with a custom made impedance analyzer for the course of 100 days. During this time, the probes are subjected to 37°C Ringer’s solution to mimic the targeted biological environment, not yet taking into account biological degradation factors. Half of the electrodes on each probe are subjected to 1000 stimulation pulses with a 1 V amplitude and 1 ms duration per hour. This serves as a first evaluation for clinical applications where electrical stimulation is required. In-vivo implantations in rats and a monkey show that it is possible to stably record action potentials for 10 days, which is the approximate implantation duration for focal epilepsy diagnosis. The longest proven duration for this probe to record action potentials is 13 weeks. This corresponds to the results obtained from the electrical bench test, which indicates that electrochemical processes govern the degradation of the device. Since the electrode layer is only 300 nm thin, one hypothesis is that a thicker electrode layer will extend the lifespan of the probes. To test this hypothesis, the electrodes of one probe are galvanically plated with a thin layer of gold after the rolling process and showed no change in impedance while subjected to the 37°C Ringer’s solution over a period of 30 days. Thus, probes with an additional electrode layer or different material might overcome the observed degradation and pave the way to chronic implantation for applications exceeding 10 days of implantation. Furthermore, a thermomechanical model of the utilized polyimide substrate is established. The model provides a basis to calculate residual mechanical stress and strain in the polyimide after it has been subjected to mechanical loads, and temperatures between 22°C and 300°C for durations up to 24 hours
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
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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