1,720,982 research outputs found
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
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
Ecological and evolutionary determinants of anopheline host species choice and its implications for malaria transmission
Get PDFDespite the importance of host species choice of mosquito vectors to the epidemiology and control of malaria, our understanding of the ecological and evolutionary factors that drive the host species preference in these vectors is very limited. My PhD thesis aimed to experimentally investigate the potential ecological and evolutionary determinants of the host species choice of the African malaria vectors Anopheles arabiensis and An. gambiae s.s, which are amongst the most highly specialized and efficient malaria vectors in the world, and identify a control strategy that reduces their anthrophily.
I used a unique semi-field system where these vectors were able to interact naturally with hosts of different species to establish whether their fitness depends on type of host species, they encounter and feed upon. My initial prediction was that highly host-specific feeding behaviour of these vectors is a product of natural selection whereby mosquito fitness is highest on their naturally preferred host types. This prediction was met in An. arabiensis, whose feeding success and lifetime egg production was predicted to be higher on their naturally preferred bovid hosts. However, I did not detect any association between the preference of An. gambiae s.s for humans and their lifetime reproductive success, although they obtain larger blood meals and survived longer on these naturally preferred human hosts. These findings suggest the role of host species on mosquito fitness varies between vector species.
I then evaluated whether the host species-specific fitness of malaria vectors may be attributed to intrinsic defensive behaviours and haematological properties that make some host species being more beneficial than others. My initial prediction was that mosquito feeding success and fitness would be the highest in the absence of host defensive behaviours and, more specifically, that the least defensive host species would be the most highly preferred in nature. I have found that the feeding success (probability of obtaining a blood meal) of An. arabiensis is greater on host species with least effective defenses (e.g. bovids). However, this association was not apparent for anthrophilic An. gambiae s.s. Surprisingly, I found that the subsequent fitness (blood meal size and survival) of both vector species was generally greater on hosts who were free to exhibit defensive behaviours than those whose behaviours were restricted. These findings suggest that natural physical defensive behaviours made by hosts including humans may not impose strong fitness costs to malaria vectors. Therefore, I conclude that if natural host defensive behaviours shape the host species preference of malaria vectors they do so by influencing the probability of acquiring a blood meal but not the value of the blood meal if obtained.
I also assessed whether the nutritive value of host blood, as determined by haematological properties of packed cell volume (PCV) and haemoglobin concentration (Hb), could explain variation in fitness of malaria vectors on different host species. I found that the PCV and Hb of host species that are commonly encountered by malaria vectors in their natural environments vary significantly. I further found that the variation in these haematological properties influence the feeding success (e.g. blood intake rate) of the anthrophilic An. gambiae s.s but not the An. arabiensis. Anopheles gambiae s.s obtain full blood meal faster on hosts with low and medium levels of PCV. Surprisingly, these haematological traits were predicted to have opposite effects on the survival of both vector species. The survival of An. gambiae s.s was positively correlated with host PCV, but negatively correlated with their Hb. In contrast, the survival of An. arabiensis was predicted to be positively correlated with host Hb, but negatively related with PCV. Overall, there was no clear evidence that haematological properties of the host species preferred by these mosquito vectors are optimal for their fitness.
I then extended my investigations to a laboratory investigation to measure the impact of host species diversity on the fitness of An. gambiae s.s throughout their life. Under these conditions, I found that An. gambiae s.s had similar fitness after either feeding on a uniform (human-only) or mixed host species. These findings indicate that the blood composition of different species may be unlikely to reduce the fitness of An. gambiae s.s
My PhD thesis also experimentally measured the impact of using simple intervention (e.g. an untreated bed net) on reducing the fitness of malaria vectors that acquire from human hosts. I found that the lifetime reproductive output of An. arabiensis on protected human was significantly lower than on bovid hosts. In contrast, the use of untreated nets by humans reduced survival of anthrophilic An. gambiae s.s, but the reduction was not predicted to be sufficient to significantly reduce the total lifetime reproductive output of these mosquitoes on human hosts than on animal alternatives. These findings suggest that the widespread use of simple untreated net may generate selection pressures for An. arabiensis to maintain their feeding on bovid hosts and to a lesser extent for An. gambiae s.s to reduce their anthrophily.
The findings of my PhD research have implications for the epidemiology and control of malaria. I found that host species and their intrinsic properties may influence aspects of the feeding success, blood meal size and survival of malaria vectors which are the key determinants of malaria transmission intensity. I further demonstrate that selectively protecting humans with untreated nets may generate selection pressures for malaria vectors to reduce their anthrophily and consequently the transmission intensity of malaria. These findings suggest integrating existing interventions (e.g., use of untreated and insecticide treated bed nets) with environmental management that increases availability of an alternate host species (e.g. zooprophylaxis) may generate selection pressures for An. gambiae s.s to reduce their anthrophily, and An. arabiensis to maintain their feeding on alternative animal hosts (zoophily).
Overall, I discuss the impacts of host species choice and intrinsic host factors on the fitness of African malaria vectors, the impacts of intervention on their fitness and their potential to select for a host shift, and the implications to epidemiology and control of malaria. I finally highlight gaps in the knowledge of the evolution of host species choice in malaria vectors where more research is required
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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