1,720,967 research outputs found
A Longitudinal Follow-up Study of Saffron Supplementation in Early Age-Related Macular Degeneration: Sustained Benefits to Central Retinal Function
No full text""Purpose. In a previous randomized clinical trial (Falsini et al., 2010), it was shown that short-term saffron supplementation improves retinal flicker sensitivity in early age-related macular degeneration (AMD). The aim of this longitudinal, open-label study was to evaluate whether the observed functional benefits from saffron supplementation may extend over a longer follow-up duration.. Methods. Twenty-nine early AMD patients (age range: 55-85 years) with a baseline visual acuity > 0.3 participated in the study. They underwent clinical examination and a Focal ERG (fERG)-derived macular (18°) flicker sensitivity estimate1 every three months over an average period of treatment (saffron 20 mg\\\/day) and follow-up of 14 (± 2) months. Visual acuity and fERG sensitivity, derived from the estimated response amplitude thresholds, were the main outcome measures.. Results. After three months of supplementation, mean fERG sensitivity improved by 0.3 log units compared to baseline values (p < 0.01), and mean visual acuity improved by two Snellen lines compared to baseline values (0.75 to 0.9, p < 0.01). These changes remained stable over the follow-up period.. Conclusions. These results indicate that in early AMD saffron supplementation induces macular function improvements from baseline that are extended over a long-term follow-up.. "
One-Year Follow-Up of Saffron Supplementation in Early AMD: Stable Improvements in Retinal Flicker Sensitivity and Visual Acuity
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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
Retinal Dysfunction and Complement Factor H Polymorphism in Early Age-Related Macular Degeneration
No full textPurpose: To evaluate the association between retinal function and complement factor H (CFH) and ARMS2 gene polymorphisms in patients with early age-related macular degeneration (AMD).
Methods: Thirty-three early AMD patients (age range: 55-85 years), with preserved visual acuity (≥ 0.7) and macular lesions belonging to stage 2 of the standard international staging scheme, underwent full clinical and ophthalmic examination, focal electroretinogram (FERG) testing and gene polymorphism analysis for the CFH (Tyr402His) and ARMS2 (del443ins54) AMD susceptibility genes. FERGs were recorded from the macular region (18°) in response to 41 Hz flickering stimuli presented on a light adapting background. The amplitude and phase of the fundamental harmonic response component were measured. Gene polymorphisms were determined by TaqMan assays and polymerase chain reaction amplification.
Results: Mean FERG amplitude tended to decrease (p < 0.001) in patients hetero (by 21%)- or homozygous (by 43%) for CFH polymorphism, compared to wild type patients, although visual acuity and funduscopic features were similar across groups. FERG amplitude did not vary significantly across groups for the ARMS2 polymorphism. FERG phase did not change significantly across the different CFH or ARMS2 gene polymorphism groups.
Conclusions: The results show that retinal function can vary significantly across early AMD patients with similar fundus lesions and visual acuity, but belonging to different genetic subtypes. CFH abnormality may impact significantly on retinal function in early AMD, supporting a predictive role for progressive visual loss in individual at risk patients
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
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