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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
Climate change in a stable thermal environment: effects on the performance and life history of coral reef fish
Get PDFThe effects of climate change induced ocean warming are expected to be felt most strongly by species living at low-latitudes due to the thermally stable environments that characterise these locations. This thesis examined how near-equatorial populations of coral reef fishes, particularly A. polyacanthus, are likely to respond to increases in ocean temperatures projected to occur by the end of this century. The underlying physiological measures linked to declines in organism fitness at higher temperatures were considered, and the capacity for acclimation of these traits assessed. Whether certain populations of coral reef fishes are more or less vulnerable to projected climate change scenarios was also investigated by comparing results with those obtained in previous studies conducted at higher latitudes.
Initially I sought to understand how chronic exposure to temperatures expected to occur with climate change are likely to impact on the survival and metabolic performance of a low-latitude population of marine damselfish (Acanthochromis polyacanthus), and subsequently estimate their potential for long-term reversible acclimation to higher temperatures (Chapter 2). To do this, I assigned fish to one of three treatments: (1) current average ocean temperatures for the collection locations, seasonally cycling, (2) 1.5 °C higher than current average temperatures or (3) 3 °C higher than current average temperatures. Fish were kept in these treatments for approximately 10 months. Routine and maximum oxygen consumption were then directly measured and subsequently used to estimate net aerobic scope for each fish during both the summer and winter. Critical thermal maximum was also estimated during summer and fish survival was monitored both before and after metabolic testing. For these low-latitude populations of coral reef fish performance in terms of aerobic scope was maintained up to 31.5 °C, the maximum ocean temperature routinely experienced by this population. Once temperatures exceeded 31.5 °C, aerobic scope dropped significantly, as did fish survival. Survival was further decreased at much lower temperatures after the introduction of a secondary stressor (metabolic testing). As predicted, potential for reversible acclimation was limited, even after extended periods at elevated temperatures.
The first data chapter of this thesis confirmed that increased temperatures are likely to significantly affect the physiological performance of low-latitude coral reef fish. Studies which consider only a single measure of fitness such as aerobic scope when estimating the impacts of thermal stress on organismal health may however not obtain the best estimate of how an organism will cope under future conditions. In chapter 3 I aimed to expand the range of physiological estimators of fitness used to determine the effect of elevated temperatures on low-latitude reef fish. This chapter compared the impacts of increased ocean temperatures on aerobic scope, haematological parameters and tissue health for Torres Strait A. polyacanthus. Haematological parameters and tissue health were analysed during the summer months and compared with the measures of aerobic scope taken in the previous chapter. Haematological traits, similarly to aerobic scope, suggested an impact on oxygen transport in fish at +3 °C, however a negative impact of temperature on tissue health was observed in fish from both +1.5 and +3 °C treatments. Aneurismal dilations in the gill tissue were larger and more numerous in fish from the warmer temperatures. Findings from chapter 3 suggest multiple thermal optima, depending on the physiological trait concerned. Of the measures considered in this chapter, gill histopathology provided the best indicator of thermal tolerance, as it was the first measure to show of a decline in organism health and corresponded with mortality observations from chapter 2.
Previous research shows that increased temperatures may also effect A. polyacanthus in the future by producing populations of offspring with a strongly male biased sex ratio. This could have a significant negative impact by reducing the functional reproductive population. For a shift in sex ratio to occur, juveniles must be exposed to increased temperatures during a specific time during development, known as the thermosensitive period (TSP). In chapter 4, I aimed to determine the TSP for A. polyacanthus and subsequently predict when projected temperature increases are likely to have the greatest effect on sex ratio for this species. For this chapter only we used fish collected from a higher latitude, and so temperature treatments were adjusted accordingly. To determine the thermosensitive period of sex determination under climate change relevant temperatures for this species, a single-shift design was used to expose juvenile fish to elevated water temperatures (+1.5 and +3 ˚C) at various stages of development. Increasing grow-out temperature to 1.5 °C had no effect on the sex ratio of offspring, however an increase to 3 °C above average produced a strong male bias (average ~90%). The thermosensitive period was up to 60 days post hatching, with the bias in sex ratio greater for fish that were exposed to higher temperatures earlier in life. Average summer temperatures will need to increase by ~3°C before an effect of temperature on sex ratio is seen for this population. Temperatures high enough to drive a bias in sex ratio are likely to be first seen during January and February and would have the greatest effect on clutches produced late in the breeding season.
Based on previous chapters it was determined that the ability to acclimate to higher temperatures would be critical for the persistence of low-latitude populations in a warming world. In chapter 5 I test the capacity for three low-latitude coral reef damselfishes (Acanthochromis polyacanthus, Pomacentrus moluccensis and Pomacentrus wardi), to developmentally acclimate to ocean temperatures expected to occur by the end of this century, again using metabolic fitness as an estimate of organism health. Newly settled juveniles were collected from reef locations in Torres Strait and reared for 3 months in three different temperature treatments, this time consisting of the current-day summer average (30 °C) and 1 and 2 °C above the average (31 and 32 °C). As with chapter 2, aerobic scope was estimated, this time for each fish at both their developmental temperature and at the two remaining treatments after acute exposure. Acclimation capacity differed among species and occurred at similar absolute temperatures but lower relative temperatures than for the same species at higher latitudes. There was some scope to deal with climate change relevant temperature increases in these populations, however low-latitude populations are still more vulnerable to temperature increases than their more southern counterparts. Life history and habitat choice of each species appeared to have a strong influence on their capacity for developmental acclimation, leading to the conclusion that scientists should consider the ecological niche of their study species and take care when making generalisations about the effects of climate change, even on closely related species.
Overall, results from this thesis showed that despite substantial physiological effects of climate change, some near equatorial populations of coral reef fish do have a capacity to acclimate to higher temperatures when exposed to warmer conditions during early development. In the future, multi-generational research that investigates the capacity for transgenerational plasticity may reveal a further ability to acclimate in these populations, beyond what has been shown in this thesis for developmental acclimation. The importance of understanding the life history of model species was also highlighted, as it was shown that a species' capacity for acclimation is likely to be strongly effected by their ecological niche. This thesis represents the most comprehensive investigation into the effects of projected climate change on low-latitude coral reef fish to date and is the first to examine the acclimation capacity of fish at these latitudes. Although acclimation was observed in low-latitude populations, near-equatorial fish were still more vulnerable to increased temperatures when compared with higher latitude populations. Based on the findings of this thesis, low-latitude populations should be considered a high priority for research and management into the future
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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