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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
Genesis of the E1 group of iron oxide-copper-gold deposits, Cloncurry district, North West Queensland
Get PDFThe E1 Group of iron oxide-copper-gold (IOCG) deposits is located in the metal-rich Cloncurry District of northwest Queensland. The E1 Group contains a total resource of 47 Mt averaging 0.72% Cu and 0.21 g/t Au, and has not been previously investigated in detail. This study aims to understand the genesis of the E1 Group by characterising its geology, alteration paragenesis, ore chemistry, structural controls, and mineralising fluid properties. These features are investigated using drill core logging, petrography, whole-rock geochemistry, microprobe analysis, LA-ICP-MS U-Pb dating, 3-D implicit geological modeling, fluid inclusion studies, and SHRIMP and IRMS oxygen and sulfur stable isotope analyses.
The E1 Group comprises three distinct orebodies: E1 North, E1 East and E1 South. The orebodies are hosted mainly in marble and carbonaceous metasiltstone of the Corella Formation (1750–1720 Ma). The metasedimentary rocks are intercalated with mineralised clastic metavolcanic rocks and barren meta-andesite of the Mount Fort Constantine Volcanics (~1750 Ma). These rocks were intruded by Ernest Henry Diorite, cut across by a discordant, polymictic, breccia, and then intruded by dolerite.
Drill core logging, petrography and Mineral Liberation Analysis were used to study the E1 Group alteration textures and styles. They show that E1 Group mineralisation is typified mainly by fine- to medium-grained (<500 μm) stratabound and shear zonehosted replacement bodies. The ores are typically layer-controlled; some ores are also in veins. The discordant breccia is barren, and pre-dates mineralisation.
The alteration paragenesis was constrained with drill core logging, petrography, and Energy-Dispersive and Wavelength-Dispersive analyses. The E1 Group paragenetic sequence is characterised by three major stages. Stage 1 is dominated by albite (- hematite), with lesser quartz, actinolite, scapolite, and titanite. The second stage is broken into three sub-stages. Stage 2a is dominated by magnetite, fluorophlogopite and fluorannite, fluorapatite, K (-Ba)-feldspar and lesser quartz and pyrite. Stage 2b is a minor phase of albite (-hematite)-rutile-ilmenite alteration. Stage 2c is composed of ankeritic carbonate, magnetite, pyrite, and minor chalcopyrite. Stage 3 is the main mineralising event, and is dominated by carbonate (-Fe-Mn), chalcopyrite, barite, fluorite, pyrite, chlorite, sericite; trace amounts of monazite, bastnäsite, uraninite and coffinite are also present.
Whole-rock geochemical analysis indicates that the ores are highly enriched in Fe, Ba, F, P, and locally Mn, and are less enriched in U, LREE, Co, Mo, As, Sn, Ag while depleted in Si, Na and K. Delineation of the deposit zonation patterns shows a transition from the E1 North orebody into a barren magnetite-apatite ± pyrite zone to the southwest. Barium and fluorine are elevated over 200 m from mineralisation.
The relatively new technique of three-dimensional implicit geological and geochemical modeling was used to study the structural history and controls of the E1 Group. The deposit is hosted within a series of northwest-plunging folds that formed during regional D2 deformation event and peak metamorphism. The E1 North and E1 South orebodies are hosted in the hinges of the E1 North Antiform and E1 South Synform, respectively, while E1 East occurs in the limb of the E1 East Antiform. The E1 North Antiform is cut by the northeast-southwest-trending brittle-ductile E1 North Shear Zone that dips ~70° northwest. The shear zone is an R-shear of a dextral Riedel structure caused by transpressional movement on the regional Mount Margaret Fault during local D3 / regional D4. Implicit geochemical modeling suggests that the spatial distributions of Cu, Au, Fe, U, Co, Mo, and La are controlled by the fold hinges and E1 North Shear Zone, and the highest-grade orebody occurs at their intersection. Drill core and petrographic observations indicate that ore formation took place around local D3 / regional D4. A later local D4 / regional D5 event caused brittle reactivation of the E1 North Shear Zone and formed northeast-southwest-trending reverse-oblique faults at E1 South that offset mineralisation.
Fluid inclusion analyses were conducted on Stage 2a quartz and Stage 3 barite to determine the composition of the mineralising fluids. Stage 2a quartz hosts a primary fluid inclusion assemblage, 1A, that is characterised by halite-rich, aqueous liquid-solidvapour fluid inclusions with >50 wt% NaCl(eq); the assemblage was heterogeneously trapped. Stage 3 barite hosts two major fluid inclusion assemblages (2A and 2B). Assemblage 2A comprises primary, moderate to low salinity (<15 wt% NaCl(eq)) aqueous liquid-vapour, inclusions that homogenise between 160° and 190°C. Assemblage 2B is composed of secondary, moderately saline (<9 wt% NaCl; <18 wt% CaCl₂), liquidvapour inclusions.
In order to constrain fluid and metal sources and precipitation mechanisms, the δ¹⁸O(VMSOW) values of Stage 2a quartz-magnetite pairs, along with the δ³⁴S(CDT) values of and Stage 3 barite-chalcopyrite pairs, were studied; Stage 2 pyrite was also measured. For fine-grained ores, the in-situ Sensitive High Resolution Ion Microprobe method was used, while conventional ex-situ Isotope Ratio Mass Spectrometry was used for vein samples. Stage 2 quartz δ¹⁸O values at E1 North have a narrow range of +12.7 to +14.8‰. In contrast, magnetite δ¹⁸O values are characterised by a wider range from 0 to +8‰. Calculated isotopic equilibrium temperatures from quartz and magnetite range from 350° to 540°C, and the calculated δ¹⁸O range of the fluid at these temperatures is +8.4 to +10.9‰.
Stage 3 chalcopyrite δ³⁴S values are distinct between E1 North (–5.8 to +2.7‰), E1 South (+1.7 to +17.3‰), and E1 East (+12.5 to +16.9‰). Stage 3 barite δ³⁴S values vary from +6.7 to +21.2‰ in E1 North, +19.1 to +29.5‰ in E1 South, and +5.6‰ to +26.5‰ in E1 East. Vein-hosted barite δ³⁴S values are 5 to 10‰ lower than those in fine-grained samples. Stage 2 pyrite is typically 1 to 2‰ higher than Stage 3 chalcopyrite. Calculated equilibrium temperatures for Stage 3 barite and chalcopyrite in fine-grained samples range from 230° to 340°C; vein-hosted samples did not reach equilibrium. Estimated trapping pressures of barite 2A fluid inclusions, based on these temperatures, range from 2.2 to 3.3 (±0.5) kbar. This corresponds to a depth range of 8– 12 km. The estimated values of δ³⁴S(Σ)ₛ range from +4.9 ± 5.3‰ at E1 North, to +15.9 ± 3.6‰ at E1 South.
The δ¹⁸O(fluid) and δ³⁴S(Σ)ₛ values at E1 North, coupled with the high salinity of 1A fluid inclusions, are consistent with those from a magmatic-hydrothermal fluid. The F-UREE enrichment of the paragenesis suggests that the magma was an evolved, alkaline, granite. It is speculated that this granite was related to the (1550–1490 Ma) Williams- Naraku Batholith; it may have supplied some of the Cu and Au. The shifts in the values δ³⁴S(mineral) and δ³⁴S(Σ)ₛ at E1 South can be explained by mixing of the magmatic fluid with a shallower fluid that had equilibrated with the Corella Formation host rocks. Covariance of the δ³⁴S of barite and chalcopyrite between E1 North and South suggests that both fluids supplied SO²⁻₄. Ore precipitation was likely caused by salinity decrease as a result of fluid-fluid mixing. Dilation in the E1 North Shear Zone and fold hinges during local D3 / regional D4 provided the main conduits for mixing of the mineralising fluids
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
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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