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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
High level relativistic calculations on transition metal complexes
No full textTesis (Doctor en Fisicoquímica Molecular)For calculating properties on molecules that contain heavy elements of the periodic
table, only a theory that salves the four-component Dirac equation is suitable. In
effect, scalar relativistic effects can stabilize s and p orbitals and destabilize d and f
orbitals. In this context bond lengths and other spectroscopic constants can change
drastically going from the non-relativistic to the relativistic framework. On the other
hand, the spin-orbit effect could change completely the assignment of the ground
state of a molecule.
This thesis is a study of the Jahn-Teller effect in six heavy transition-metal complexes
(RhF6 , WF6 , ReF6 , OsF6 , IrF6 , PtF6). In these complexes, the relativistic
effects and electron correlation are large, therefore in order to obtain reliable results,
all calculations have been carried out by solving the four-component Dirac equation.
Dirac-Hartree-Fock (DHF) and correlated Density Functional Theory (DFT)
methods were applied. The use of a four-component code involves a very demanding
computational effort and nowadays it is considered a state-of-the-art method.
The main results consisted in assigning the ground state and the geometry of the
six complexes. Experimentally, the complex PtF6 is essentially diamagnetic ("singlet")
and strictly octahedral, but previous theoretical studies had determined that
it should distort due the J ahn-Teller effect and that its ground state should be a
"triplet". The explanation of this contradiction is that the previous studies did not
included the spin-orbit interaction. In contrast, the results in this thesis show unequivocally
that PtF 6 is octahedral and that the J ahn-Teller effect is quenched by the
spin-orbit effect. The other interesting case is IrF6 , since a non-relativistic or scalar
relativistic description would show that this complex is not J ahn-Teller-distorted
and must be octahedral, like its isoelectronic counterpart RhF6 . However, the results
of this thesis indicate that IrF6 must distort, which is in complete agreement
with experimental results. The results conclude that the J ahn-Teller must be studied including the spin-orbit
interaction when the systems considered have heavy-metal nuclei. The spin-orbit
effect could change the assignment of the ground state of the complexes studied,
therefore if the J ahn-Teller effect is applicable in the non-relativistic framework, it
could be canceled out in the relativistic one.
In general, the criterion usually used to predict the existen ce of the J ahn-Teller
effect in molecules with light atomic nuclei, is not valid anymore when the atomic
nuclei are heavy.Para calcular propiedades de moléculas que contienen elementos pesados de la tabla
periódica, sólo es adecuada una teoría que resuelva la ecuación de Dirac ele cuatro
componentes. Los efectos escalares relativistas pueden estabilizar los orbitales s ancl
p y desestabilizar los orbitales d and f. En este contexto, las longitudes ele enlace
y otras constantes espectroscópicas pueden cambiar drásticamente al pasar desde el
marco no-relativista al relativista. Además la interacción espín-órbita puede cambiar
el estado fundamental ele una molécula.
En esta tesis se ha estudiado el efecto J ahn-Teller en seis hexafiuoruros de atamos
ele transición pesados (RhF6 , 'lvF6 , ReF6 , OsF6 , IrF6 , PtF6). En estos complejos,
tanto los efectos relativistas como la correlación electrónica son considerables, por
lo tanto para obtener resultados confiables se han efectuado cálculos que resuelven
la ecuación de Dirac ele cuatro componentes. Se aplicó la teoría de Dirac-HartreeFock
(DHF) y el método correlacionado Teoría del F\mcional ele la Densidad (DFT).
El uso ele un programa de cuatro componentes implica un esfuerzo computacional
enorme y hoy en día es considerado el método de cálculo más sofisticado existente.
Los principales resultados consistieron en determinar el estado fundamental y la
geometría de estos seis complejos. Experimentalmente, el complejo PtF6 es esencialmente
diamagnético ("singlete") y estrictamente octahédrico, pero estudios teóricos
previos habían determinado que éste debería distorsionar debido al efecto JahnTeller,
además que su estado fundamental debería ser un "triplete". La explicación
de esta contradicción está en que los estudios previos no consideraron la interacción
espín-órbita. En contraste, los resultados de esta tesis determinaron inequívocamente
una estructura octahédrica indicando que el efecto Jahn-Teller es cancelado debido
al efecto espín-órbita. El otro caso interesante es IrF 6 , puesto que una descripción
no-relativista o escalar relativista indicaría que este complejo no distorsiona
por Jahn-Teller y debe ser octahédrico, tal como ocurre con RhF6 , el cual es iso-electrónico a IrF6 . Sin embargo, los resultados de esta tesis indican que IrF6 debe
distorsionar, lo cual está de acuerdo con resultados experimentales.
Los resultados concluyen que el efecto .J ahn-Teller debe ser estudiado con la
inclusión de la interacción espín-órbita cuando los sistemas considerados contienen
nucleos atómicos pesados. El efecto espín-órbita puede cambiar completamente el
asignamiento del estado fundamental de los complejos estudiados, en consecuencia
si el efecto .Jahn-teller es aplicable en el cuadro no-relativista, este efecto podría ser
cancelado en el relativista.
En general, el criterio usado normalmente para predecir la existencia del efecto
.J ahn-Teller en moléculas con nucleos atómicos livianos, ya no es aplicable cuando
los nucleos atómicos son pesados
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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