1,720,956 research outputs found
Brain activity patterns in two tasks involving reward downshift
Get PDFConjunto de datos referentes a estudio de conectoma en dos situaciones de contraste sucesivo negativo, generadoras de frustración en animales. Se incluyen los datos conductuales y de expresión de c-Fos (Excel), y documento en preparación para su publicación.Frustrative nonreward (FNR) is a reaction associated with the sudden and unexpected loss of significant sources of reinforcement: the death of a loved one, job dismissal, heartbreak, or restrictions associated with health crises, among others. These experiences can profoundly impact physical and mental well-being. Although the scientific study of frustration using animal models provides abundant information, there remains a gap in knowledge regarding the underlying functional brain circuits involved. This study addressed this issue using two frustration paradigms successive negative contrast (SNC) in rats. In Task 1 (pavlovian SNC), training involved forced-choice trials with a single retractable lever served as a conditioned stimulus (CS) for the response-independent delivery of 12 pellets, while the other lever CS was paired with the delivery of 2 pellets. Although pressing the lever was not required to receive the pellets (i.e., a response-independent Pavlovian procedure), lever pressing increased steadily during these sessions. However, no clear differences emerged between the two levers during these forced-choice trials. After lever pressing was established, rats received occasional free-choice trials with both levers presented simultaneously in the absence of food and lever presses at each lever were recorded. In the same session in which rats had produced similar lever presses to each lever during forced-choice trials, animals pressed the lever associated with 12 pellets more than the lever paired with 2 pellets. This free-choice trial was a reward magnitude test. In the following sessions, the lever previously paired with 12 pellets was downshifted to 2 pellets, whereas the other lever remained associated with 2 pellets as an unshifted control. Again, forced-choice trials with a single lever provided no evidence of a difference in lever pressing between downshifted and unshifted levers. However, occasional free-choice trials revealed a switch to responding in the unshifted lever and away from the downshifted lever. This was the reward downshift test. The Task 2 (consummatory SNC) entailed providing animals with 10, 5-min sessions of access to a highly reinforcing sucrose solution (32%), which was then abruptly reduced to 2% over four sessions. Consumption by this group was compared with that of a control group that consistently has access to the 2% solution. The effect refers to the decrease in consumption of the 2% solution in the experimental group (previously exposed to the sweeter 32% solution) to levels below those of the control group (always exposed to the less sweet 2% solution), despite both solutions being identical in magnitude. Expression levels of c-Fos, a marker of neuronal activity, were quantified across Regions of Interest (ROIs), and a neural network based on these results was developed. Graph theory analysis was employed for a preliminary exploration of the network's functional properties. The results indicated that, in Task 1, the Downshift network became more modular and locally interconnected but less globally integrated, implying a shift toward specialized processing within tightly knit communities at the cost of efficient long-range communication. This architecture may have indicated reduced whole-brain communication efficiency, a dominance of local processing, and potentially an adaptive or compensatory response to lowered global drive or integration demands. In contrast, the Magnitude group appeared to display shorter path lengths, reduced modularity, and higher small-worldness, reflecting a more globally integrated topology that supported efficient cross-regional coordination. With respect to Task 2, the connectome of the Group 32-2 exhibited lower clustering and modularity but longer path length and higher small-worldness. This pattern pointed to a less segregated, less locally clustered, and less globally efficient network that nevertheless maintained a non-random small-world architecture relative to baseline. In contrast, functional network of the Group 2-2 represented a more locally coherent, modular, and efficient topology. Functionally, the 32-2 configuration may have reflected reduced local specialization and weaker short-range processing, longer routes for inter-regional communication (i.e., reduced efficiency), and a preserved global balance (higher σ), possibly indicating a compensatory or reorganized small-world state under emotional demanding conditions. Taken together, these results highlight that cognitive or motivational manipulations can reshape whole-brain topology in systematic ways, providing insights that extend beyond traditional studies focused on isolated regions or localized neural activations. Whereas classical approaches often emphasize increases or decreases in activity within specific areas, the present network-level perspective reveals how the brain reorganizes its global communication architecture—how modules strengthen or loosen, how integration fluctuates, and how efficiency shifts across conditions. This broader systems-level view offers a more comprehensive understanding of how cognitive states emerge from coordinated patterns of connectivity rather than from the activity of single regions in isolation.Agencia Española de Investigación. Universidad de Jaén (CICT). Texas Christian University
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
- …
