1,721,053 research outputs found
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
Impeding Exciton-Exciton Annihilation in Monolayer WS2 by Laser Irradiation
No full textMonolayer (1L) transition metal dichalcogenides (TMDs) are two-dimensional direct-bandgap semiconductors with promising applications of quantum light emitters. Recent studies have shown that intrinsically low quantum yields (QYs) of 1L-TMDs can be greatly improved by chemical treatments. However, nonradiative excitonexciton annihilation (EEA) appears to significantly limit light emission of 1L-TMDs at a nominal density of photoexcited excitons due to strong Coulomb interaction. Here we show that the EEA rate constant (gamma) can be reduced by laser irradiation treatment in mechanically exfoliated monolayer tungsten disulfide (1L-WS2), causing significantly improved light emission at the saturating optical pumping level. Time-resolved photoluminescence (PL) measurements showed that ? reduced from 0.66 +/- 0.15 cm(2)/s to 0.20 +/- 0.05 cm(2)/s simply using our laser irradiation. The laser-irradiated region exhibited lower PL response at low excitation levels, however at the high excitation level displayed 3x higher PL intensity and QY than the region without laser treatment. The shorter PL lifetime and lower PL response at low excitation levels suggested that laser irradiation increased the density of sulfur vacancies of 1L-WS2, but we attribute these induced defects, adsorbed by oxygen in air, to the origin for reduced EEA by hindering exciton diffusion. Our laser irradiation was likewise effective for reducing EEA and increasing PL of chemically treated 1L-WS2 with a high QY, exhibiting the general applicability of our method. Our results suggest that excitonexciton interaction in 1L-TMDs may be conveniently controlled by the laser treatment, which may lead to unsaturated exciton emission at high excitation levels
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
Characterization of the structural defects in CVD-grown monolayered MoS2 using near-field photoluminescence imaging
No full textStructural defects can critically influence the electrical and optical properties of monolayered molybdenum disulfide (MoS2) grown by chemical vapor deposition (CVD); thus, convenient optical methods that can visualize grain boundaries (GBs) and other structural defects are in great demand. Although photoluminescence (PL) imaging can identify the presence of relatively large defects, the limited spatial resolution of PL imaging prevents the identification of nanosized structural defects in the monolayered MoS2. Additionally, the origin of the PL signal contrast observed at certain types of structural defects, such as GBs, is not yet understood. Here, we present near-field PL images of CVD-grown monolayered MoS2, collected to identify nanosized line defects and adlayer defects in the monolayered MoS2. Our results of correlated scanning electron microscopy imaging and the inspection of near-field PL profiles of line defects and GBs suggest that decreased PL on GBs is due to the local physical damage of the MoS2 film rather than due to the presence of localized states. This journal is © The Royal Society of Chemistry139381sciescopu
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
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