1,354,059 research outputs found

    Optical coherence tomography evidence on the correlation of choroidal thickness and age with vascularized retinal layers in normal eyes

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    Purpose: To correlate choroidal thickness (CT) and age with vascularized retinal layer and outer retinal layer thickness in normal eyes. Methods: This was a prospective, cross-sectional study. Complete ophthalmological examination, biometry, and enhanced depth imaging spectral domain optical coherence tomography were performed. Choroidal and individual retinal layer thickness measurements were obtained. Thickness maps for all layers were evaluated using the 1 mm, 3 mm, and 6 mm early treatment diabetic retinopathy study (ETDRS) macular grid areas. Results: One hundred and twenty eyes were included. Choroidal thickness correlated negatively with age in all ETDRS areas. The ganglion cell layer (GCL) in the 1 mm; the GCL and inner plexiform layer (IPL) in the 3 mm and 6 mm; and the GCL, IPL, and inner nuclear layer in the 6 mm areas correlated negatively with age and positively with CT. Retinal nerve fiber layer thickness in the 6 mm area correlated negatively with age. The retinal pigment epithelium-photoreceptor layer in all areas correlated negatively with age and positively with CT. Conclusion: In normal subjects, vascularized retinal layer thicknesses and outer retinal layer thickness correlate positively with CT and negatively with age. The role of neuronal versus vascular components should be considered when evaluating individual retinal layer thicknesses

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The 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

    Correlation between specratl-domain optical coherence tomography findings and visual outcome after primary rhegmatogenous retinal detachment repair.

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    Purpose: To correlate the postoperative visual outcome with the spectral-domain optical coherence tomography (SD-OCT) findings in the fovea after successful rhegmatogenous retinal detachment repair. Cross-sectional, observational study. Methods: Thirty-five patients with preoperative macula-on rhegmatogenous retinal detachment (12 eyes) and macula-off rhegmatogenous retinal detachment (23 eyes) who underwent scleral buckling surgery for primary rhegmatogenous retinal detachment were recruited. Early Treatment Diabetic Retinopathy Study best-corrected visual acuity measurement, microperimetry, and SD-OCT examination were performed on the same day. Foveal center retinal thickness, central 1-mm subfield thickness, and outer nuclear layer thickness were measured using SD-OCT. The presence or absence of epiretinal membrane, intraretinal fluid, and subretinal fluid was assessed. The status of the external limiting membrane, inner/outer segment junction, and intermediate line was also evaluated and judged as disrupted or complete. The correlations between SD-OCT findings and either postoperative best-corrected visual acuity or retinal sensitivities for central 12 degrees were analyzed. Results: The outer nuclear layer thickness was the only significant SD-OCT retinal measurement strongly correlated with both postoperative best-corrected visual acuity (r = 0.61; P < 0.001) and retinal sensitivities for central 12 degrees (r = 0.53; P = 0.001). Among the SD-OCT imaging findings, status of the external limiting membrane, inner/outer segment junction, and intermediate line and the presence of intraretinal fluid showed a significantly high correlation either with best-corrected visual acuity outcome (r = -0.60; P < 0.001, r = -0.63; P < 0.001, r = -0.66; P < 0.001, and r = -0.50; P = 0.002, respectively) or with postoperative retinal sensitivities (r = -0.59; P < 0.001, r = -0.61; P < 0.001, r = -0.66; P < 0.001, r = -0.50; P = 0.002, respectively). Multivariate analysis showed that the outer nuclear layer thickness and the status of the intermediate line were the most important predictors of visual outcome (P, 0.001 and P, 0.001, respectively). Conclusion: This study showed that not only the status of the external limiting membrane and the inner/outer segment junction but also the integrity of the intermediate line and the outer nuclear layer thickness changes may be important predictors of postoperative visual outcome after anatomically successful rhegmatogenous retinal detachment repair. RETINA 32:43-53, 201

    Variations on the Author

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    “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

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    We 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

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    We 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

    Author, publisher and bookseller : a tripartite synergy in Nigerian book industry

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    This work is about the roles of Author, Publisher and Bookseller in Book development in Nigeria. The paper started by delving into the history of Book Publishing in Nigeria after which it proceeded by defining who an author, a publisher, and a bookseller is and expatiated on the indispensable roles of these key actors in Nigerian Book Industry and in the emerging Information Society. Furthermore, the various constraints to book development were identified while the paper advised on how the Book Industry can be further promoted in Nigeria. However, the paper concluded and made recommendations on how the Book sector can help in enhancing scholarship in the country

    The Thursday Murder Club: Launching a megabrand author - a publishing case study

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    In 2020, the Christmas book charts in the UK made headlines: Barack Obama’s eagerly awaited autobiography, The Promised Land, was beaten to the top spot by The Thursday Murder Club by Richard Osman, a debut cosy crime novel set in a retirement village. Not only did Osman’s book beat the former US president’s expected bestseller, it also broke records, becoming the fastest-selling debut crime novel of all time. Although Osman has a certain level of fame in the UK from his TV appearances on shows such as Pointless, his celebrity status does not entirely explain the novel’s huge sales. This article tracks the acquisition, publication, and promotion journey of The Thursday Murder Club in order to understand the industry and cultural context of its success and to interrogate the role of celebrity in the creation of author brands. The findings suggest that the unexpected scale of the success of the book owed to a number of factors, including in-depth editing by the novel’s agent, editor, and author to tighten up the plot, an extensive and strategic promotional campaign, the pandemic (which drove interest in the book’s genre and themes), and the quality of the writing. We find that the book’s success was accentuated by Osman’s celebrity status rather than being entirely reliant on it. This research adds to the growing scholarship on celebrity authorship by means of an in-depth case study and provides insight into the processes behind publishing a ‘celebrity’ book and launching a megabrand author

    Choroidal Neovascularization in Pathologic Myopia: Intravitreal Ranibizumab Versus Bevacizumab—A Randomized Controlled Trial

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    treating myopic choroidal neovascularization (CNV). ? DESIGN: Prospective, comparative, randomized, interventional study. ? METHODS: Thirty-two eyes from 32 patients with myopic CNV were consecutively enrolled and randomly treated, in a 1:1 ratio, with intravitreal ranibizumab (0.5 mg) or bevacizumab (1.25 mg) as needed, after the first injection. ETDRS best-corrected visual acuity (BCVA), foveal center thickness (FCT) on optical coherence tomography (OCT), and fluorescein angiographic findings were examined before and after treatment. Patients were followed up for 6 months. ? RESULTS: No statistically significant difference in the BCVA improvement, as well as in the FCT reduction, was found between groups during follow-up (P value at 1, 3, 6 months > .05). Complete resolution of fluorescein leakage was observed in all 16 bevacizumab-treated eyes and in 15 out of 16 (93.7%) ranibizumab-treated eyes. No ocular or systemic adverse effects from treatment were encountered. ? CONCLUSION: This randomized clinical study cannot determine a statistically significant difference in anti- VEGF treatment effect between ranibizumab and bevacizumab for the treatment of CNV secondary to pathologic myopia. A larger study is required to determine the relative efficacy and duration of action of these drugs. (Am J Ophthalmol 2010;149:458–464. © 2010 by Elsevier Inc. All rights reserved.

    Choroidal Neovascularization in Pathologic Myopia

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    With regard to the power calculations please note the following. The population covered by the present study consists of all subjects potentially affected with myopic CNV. It is a population of modalities, and therefore, is unlimited. The sample was selected according to inclusion and exclusion criteria, mentioned in the “Methods.” From a statistical point of view, it is a simple, random, no orderly sample without replacement: it is a nonprobabilistic sample with reasoned choice, which does not allow the application of the Horvitz-Thompson estimator to estimate variance, and then errors and best sample size. We elected to enroll every eligible patient who sought treatment from February 2008 through December 2008; therefore, the sample size was left to chance. The 1-tailed paired t test we used to compare the best-corrected visual acuity (BCVA) results applies with the compound hypothesis; therefore, the test power 1 - beta cannot be determined by the Neyman-Pearson lemma. The Neyman-Pearson test, indeed, applies to the case of a simple null hypothesis against a simple alternative hypothesis; on the contrary, the 1- beta varies with an alternate hypothesis. With a sample size of 16 patients in each arm, we found a standard deviation equal to 8.413 for BCVA in the bevacizumab group. We can assume a prudential alternate hypothesis of BCVA improvement equal to 7 letters; given an alfa error of 5%, we obtain a power of 0.942, and therefore a beta error of 5.8%. As for the proportional confidence interval of a complication rate, it is absolutely arbitrary to evaluate as 25% because we could not examine the problem, not being detected over all of the 32 patients. This means that the probability of complications is less than 3%, corresponding to a maximum proportional confidence interval equal to 11.7%, with an error of 5%
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