1,720,971 research outputs found
Evaluation of acute alcohol intoxication as a model of cerebellar disease
No full textThe cerebellum is one of the most sensible regions to alcohol effect, since ethanol directly interacts with the functioning of synapses in the cerebellar cortex. Cerebellar patients manifest deficits of cerebellar functions comparable, although stronger, to those experienced by alcohol-intoxicated subjects. Based on such similarities, my work aimed at exploiting the transient cerebellar impairment caused by alcohol in order to model cerebellar diseases, and get new insights on its role in motor control. To achieve this goal, the research activity described in this thesis has concerned the study of the effects induced by alcohol on the control of eye movements in humans and zebrafish, focusing on the gaze-holding mechanism. The gaze-holding mechanism is fundamental and is “implemented” in our CNS by means of two actors: the neural integrator and the cerebellum. Both cerebellar patients and alcohol-intoxicated subjects manifest a typical clinical ocular motor sign called gaze-evoked nystagmus (GEN): an abnormal centripetal eye drift with centrifugal correcting saccades while at eccentric gaze. Despite GEN has been extensively investigated in cerebellar patients, a detailed analysis of the influence of alcohol on gaze-dependent eye drift is still missing. Thus, as a first aim of my research, we examined gaze-holding in two groups of healthy human subjects recorded before and 30 minutes after intake of the estimated alcohol amount needed to reach a blood alcohol content (BAC) of 0.06 and 0.10%, respectively. The results presented here showed that alcohol intoxication caused a linear increase of drift velocity for all gaze eccentricities. A secondary effect, instead, was found in a subgroup of subjects, which showed an additional nonlinear increase of drift velocity at large gaze angles. Considering that similar linear and nonlinear transformations were described in patients affected by cerebellar degenerations, our results suggest that alcohol-induced GEN could provide a model of GEN in cerebellar pathology. The second part of my research aimed at understanding whether the results found in alcohol intoxicated human subjects, could be generalized to zebrafish, which has been frequently considered as potential candidate for modeling cerebellar diseases in the scientific literature. To pursue such aim, we exploited the advantages of using a simpler vertebrate as a model organism and the analogies between alcohol-induced and cerebellar-induced ocular motor abnormalities. Despite the zebrafish cerebellum shares relevant functions with the human one, the involvement of the cerebellum in the gaze-holding mechanism of the fish has not been explicitly tested yet. Thus, my study was designed to face two purposes: quantifying ethanol effects on the zebrafish ocular motor system for the first time, and elucidating the role of the cerebellum on the gaze-holding mechanism at two developmental stages, i.e. larval and juvenile.The study on larvae did not reveal any macroscopic effect on their ocular motor system, showing only a nonhomogeneous effect of ethanol on their eye movements. In juvenile zebrafish, instead, ethanol-dependent abnormalities were induced both in gaze-holding and in the saccadic system. In the former system, a nonlinear a transformation of the position-drift velocity relationship was observed, although any reduction in the time constant of the neural integrator was not statistically significant. In the latter, instead, only a reduction of saccade peak velocity and amplitude was found. Despite the observed saccadic abnormalities are partially comparable to those documented in intoxicated humans, the dissimilar alteration found in gaze-holding system after alcohol exposure suggests that cerebellar involvement in eye movement control may be limited in zebrafish. Such limitation pointed out that zebrafish may not be a suitable model organism for cerebellar diseases, although it is widely used in ophthalmic research
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
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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