1,720,953 research outputs found
A Minimally-Invasive Method for the Induction of Permanent Myocardial Infarction in Mice: A Novel Approach
No full textApproximately 25% of patients suffering from acute myocardial infarction (MI) develop heart failure, with a survival rate of only 50% beyond five years, primarily due to adverse remodeling of the left ventricle. The mechanisms driving the progression to heart failure
remain poorly understood. To address this, preclinical models of MI have been developed globally to better comprehend the disease’s prognosis and to explore potential therapeutic interventions. However, these models rely on the open-chest thoracotomy technique, which exposes the heart for 25 to 30 minutes, increasing the risks of bleeding, infection, larger wound size, pericardial rupture, and aggressive ligation of the left anterior descending (LAD) coronary artery using a 7-0 curved needle, damaging surrounding tissues. Despite various strategies to minimize thoracotomy size, reduce bleeding, and improve outcomes, variability across animal models remains significant. Advances in biomedical technology, enable the induction of MI in a more minimally invasive manner. The aim of this study is to establish a minimally-invasive technique able to induce MI, to validate its efficacy by conducting a comparative analysis against the standard invasive
MI model, and to demonstrate that the minimally-invasive technique is able to induce MI with varying sizes. Our study used echocardiography and Doppler imaging, capable of visualizing and precisely locking onto the LAD artery at more than 250 frames per second (fps) for real-time observation in a stable position coupled to an electrocauterization
needle that is able to occlude the LAD in seconds (in plane needle guidance to the LAD). Cardiac parameter analysis demonstrated a significant reduction in Ejection Fraction (EF), and echocardiographic assessment of the left ventricle (LV) revealed akinesia of the anterior wall, confirming successful occlusion of the left anterior descending artery (LAD). Additionally, hemodynamic parameters, including left ventricular end-systolic volume (LVESV) and left ventricular end-systolic diameter (LVESD), exhibited marked increase following MI. These findings were consistent with some of results observed in the invasive MI model. Histological analysis further indicated an increase in infarct size and collagen deposition in both the novel and invasive MI models. Notably, the pericardium remained intact in the minimally-invasive technique, whereas it was disrupted in the invasive model. The minimally-invasive model demonstrated its capability to induce varying MI sizes by using pulse wave (PW) Doppler velocity to LAD artery occlusion. Our findings indicate that occlusion of the LAD at regions with higher blood flow results in larger MI, as evidenced by a significant reduction EF, with similar correlations observed for other MI sizes. In conclusion, our minimally-invasive myocardial infarction model offers a superior alternative to the invasive MI model for adoption in research laboratories globally. This approach provides higher translational relevance to clinical settings, demonstrating improved efficiency, reproducibility, and the ability to induce well-controlled MI sizes. Adopting this novel minimally invasive model may therefore enhance the accuracy and applicability of preclinical research, bridging the
gap between experimental outcomes and clinical translation
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Full text linkWe 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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