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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
Funktionelle Beschreibung des Nup93 Komplexes im Kernporenaufbau
No full textThe defining attribute of the eukaryotic cell is the compartmentalization of genetic material inside the cell’s nucleus. This is possible by the existence of a double lipid bilayer: the nuclear envelope (NE). This compartmentalization enables the eukaryotic cells to separate transcription and translation both spatially and temporally. The NE comprises two membranes: the outer nuclear membrane (ONM) that is continuous with the endoplasmic reticulum and the inner nuclear membrane (INM) that is characterized by a distinct protein composition and can make contact with the chromatin and the nuclear lamina. The ONM and the INM fuse to form pores where the nuclear pore complexes (NPCs) reside. NPCs act as gatekeepers of the nucleus and are involved in nucleo-cytoplasmic transport. They also act as a physical barrier thereby maintaining distinct composition of the nucleus and the cytoplasm. NPCs are proteinaceous macromolecular assemblies ranging from 40-60 Mega Daltons in size. Despite their enormous size, NPCs are composed of approx. 30 proteins referred as nucleoporins or Nups. Most nucleoporins are organized into distinct sub complexes that act as building blocks for NPC assembly. The NPC can be roughly dissected into two parts, the structural backbone of the pore that is composed of structural nucleoporins, which establish the basic scaffold of the pore and act as anchor proteins to recruit other nucleoporins. The other portion is the functional region of the pore that is composed of mainly the FG repeats containing nucleoporins that form the central channel of the pore thereby imparting functional properties like transport and exclusion competency. In animals undergoing open mitosis the NE and the NPCs are disassembled in prophase and they must reassemble from disassembled soluble pore components and membranes as the cell enters interphase to re-establish an intact nucleus.
This thesis aims to functionally characterize the role of one of the sub-complexes that is the Nup93 complex, in NPC assembly and function. Nup93 is one of the structural complexes of the NPC. It is positioned in the pore at a region where it establishes a link between membranes of the NE and the NPC. Nup93 complex is composed of five nucleoporins: Nup53, Nup93, Nup155, Nup188 and Nup205. It was previously shown in the lab that Nup93 exists as part of two distinct complexes: Nup93-Nup188 and the Nup93-Nup205. Individually neither the Nup93-Nup188 nor the Nup93-Nup205 complexes were essential for NPC assembly. We were curious to find out if both the complex together were not essential for NPC assembly, as they have been speculated to have redundant roles in the pore.
For this we took advantage of the Xenopus laevis egg extract system (in vitro nuclear assembly reactions) and by various cell biological and biochemical assays showed that the conserved nucleoporin Nup93 is essential for NPC/NE formation and functions. Immunodepleting Nup93 (thereby co depleting Nup205 and Nup188) lead to a block in NPC and NE formation and this was rescued by addition of the full-length recombinant Nup93. Hence Nup93 could compensate for the loss of both Nup93-Nup188 and Nup93-Nup205 complexes and thereby establishing the evidence that both major components of the Nup93 complex, Nup188 and Nup205 together are not crucial for post-mitotic NPC assembly. We also found that the C-terminus of Nup93 was sufficient and essential for formation of the structural backbone of the pore. It does so by strengthening the interaction between two major structural components of the pore Nup53 and Nup155. We believe that this is a key event in the formation of the scaffold/structural skeleton of the pore and hence in post-mitotic NPC assembly. Via the N-terminus, Nup93 recruits the Nup62 complex and other FG repeats containing nucleoporins to the pore, which form the central channel of the pore. Through the central channel of the pore nucleo-cytoplasmic transport occurs and a permeability barrier is established thereby maintaining distinct environments of the nucleus and cytosol in the cell. In this way, Nup93 connects both the structural and functional regions of the NPC and serves as a decisive and critical link between the two portions. We could also show that the middle domain of Nup93 is dispensable for NPC assembly. This study also sheds light on the order of recruitment of different nucleoporins in post-mitotic NPC assembly. It places Nup93 at a crucial and strategic position wherein it serves as a link between the structural and functional parts of the pore. Our findings also elucidated the role of different domains of Nup93 and their contribution in NPC assembly and function.Das namensgebende Charakteristikum einer eukaryontischen Zelle ist die Kompartimentierung des genetischen Materials im Zellkern. Dies wird durch die Existenz einer Lipiddoppelschicht möglich: der sogenannten Kernhülle. Die Kompartimentierung ermöglicht es, Transkription und Translation räumlich und zeitlich voneinander zu trennen. Die Kernhülle besteht aus zwei Membranen: der äußeren Kernmembran, die in das endoplasmatische Retikulum übergeht, und der inneren Kernmembran, die sich durch eine individuelle Proteinzusammensetzung auszeichnet und mit dem Chromatin und der Kernlamina interagieren kann. Die äußere und die innere Kernmembran verschmelzen miteinander, um Poren zu formen, in denen die Kernporenkomplexe eingelagert sind. Die Kernporenkomplexe fungieren als Wächter des Zellkerns und sind am Transport in und aus dem Zellkern beteiligt. Zudem bilden sie eine Diffusionsbarriere aus, wodurch die unterschiedlichen Zusammensetzungen von Zellkern und Zytoplasma gewährleistet werden. Kernporenkomplexe sind makromolekulare Proteinkomplexe mit einer Größe von 40-60 Mega Dalton. Trotz ihrer enormen Größe bestehen Kernporenkomplexe nur aus etwa 30 Proteinen, den sogenannten Nukleoporinen oder Nups. Die meisten dieser Nukleoporine bilden kleinere Untereinheiten, die als Grundbausteine für den Zusammenbau der Kernporen dienen. Die Kernporenkomplexe können grob in zwei Bereiche unterteilt werden. Das strukturelle Rückgrat der Pore besteht aus strukturellen Nukleoporinen, welche das Grundgerüst der Pore vorformen und als Ankerproteine dienen, um weitere Nukleoporine zu rekrutieren. Der andere Teil ist der funktionelle Bereich der Pore, der zumeist aus Nukleoporinen aufgebaut ist, die FG-Wiederholungen tragen und den zentralen Kanal der Pore bilden. Diese Nukleoporine vermitteln die funktionellen Eigenschaften, wie die Transportfähigkeit oder den Größenausschluss der Pore.
Das Ziel dieser Arbeit ist es, die Funktion einer dieser Untereinheiten, nämlich des Nup93-Komplexes, im Kernporenaufbau und in der Kernpore selbst zu charakterisieren. Nup93 bildet einen der strukturellen Komplexe der Kernpore und befindet sich in dem Bereich der Pore, wo er eine Verbindung zwischen den Membranen der Kernhülle und dem Rest des Kernporenkomplexes herstellt. Der Nup93-Komplex besteht aus fünf Nukleoporinen: Nup53, Nup93, Nup155, Nup188 und Nup205. Es wurde bereits in unserem Labor gezeigt, dass Nup93 in zwei verschiedenen Unterkomplexen vorkommt: als Nup93-Nup188 und als Nup93-Nup205. Weder der Nup93-Nup188- noch der Nup93-Nup205-Unterkomplex waren jeweils essentiell für den Kernporenzusammenbau. Wir wollten nun herauszufinden, ob auch beide Unterkomplexe zusammen nicht essentiell für den Aufbau der Kernporen sind, da vermutet wurde, dass sie redundante Funktionen in der Pore besitzen.
Hierfür nutzten wir das Eiextrakt-System aus Xenopus Laevis (um in vitro den Kernporenaufbau nachzustellen) und zeigten mittels verschiedener zellbiologischer und biochemischer Experimente, dass das konservierte Nukleoporin Nup93 für den Aufbau der Kernporen und der Kernhülle essentiell ist. Die Immundepletion von Nup93 (wodurch Nup205 und Nup188 mitdepletiert wurden) führte zu einem Block im Kernporen- und Kernmembranaufbau und konnte durch die Zugabe von rekombinantem Nup93 aufgehoben werden. Nup93 allein konnte somit die fehlenden Nup93-188- und Nup93-205-Unterkomplexe ersetzen. Dies belegte gleichzeitig, dass die beiden größten Bestandteile des Nup93-Komplexes, Nup188 und Nup205, auch zusammen keine wichtige Rolle für den post-mitotischen Kernporenaufbau spielen. Zudem haben wir gezeigt, dass der C-terminale Teil von Nup93 notwendig und ausreichend ist, um das strukturelle Rückgrat der Pore zu bilden, indem Nup93 die Interaktion zwischen den beiden wesentlichen strukturellen Komponenten der Pore, Nup53 und Nup155, verstärkt. Wir glauben, dass dies ein entscheidender Schritt in der Ausbildung des strukturellen Rückgrats und damit für den post-mitotischen Aufbau der Kernporen ist. Nup93 rekrutiert mit seinem N-Terminus Nup62 und weitere Nukleoporine, die FG-Wiederholungen tragen, an die Pore, die den zentralen Kanal der Pore bilden. Dieser zentrale Kanal vermittelt den Transport in und aus dem Zellkern und ist für den Größenausschluss der Kernpore verantwortlich, wodurch die verschiedenen Milieus von Zellkern und Zytosol aufrechterhalten werden. Somit verbindet Nup93 den strukturellen und den funktionellen Bereich der Kernpore und fungiert als das entscheidende Bindeglied zwischen diesen beiden Regionen in der Kernpore. Wir konnten zudem zeigen, dass die mittlere Domäne von Nup93 nicht notwendig für den Kernporenaufbau ist. Diese Arbeit gibt außerdem Aufschluss über die Reihenfolge der Rekrutierung verschiedener Nukleoporine für den post-mitotischen Kernporenaufbau. Sie zeigt die bedeutsame Rolle und Position von Nup93 in der Kernpore, wo es das Bindeglied zwischen dem funktionellen und dem strukturellen Teil der Pore darstellt
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
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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