1,720,983 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
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
Micellization and gelation of aqueous solutions of star-shaped PLLA-PEO block copolymers
No full textNontoxic and biodegradable star-shaped poly((L)-lactide-b-ethylene oxide) (star PLLA-PEO) block copolymers were synthesized by the coupling reaction of two reactive precursors, a hydroxy-terminated 3-armed poly((L)-lactide) (star PLLA) and alpha-monocarboxy-omega-monomethoxypoly(ethylene oxide) (CMPEO). The chemical structure and physical properties of the resulting star-block copolymers were characterized. In the dilute aqueous solutions of star-block copolymers, micellization behavior was investigated, and over specific concentration and specific temperature, the unimer to micelle transition occurred. 1,6-Diphenyl-1,3,5-hexatriene (DPH) was solubilized in the micelle core, and the absorbance of DPH at 356 nm increased when micelle was formed. In addition, the effective diameter was highly affected by temperature. With increasing temperature, micelle size decreased dramatically. In high-concentration solution, star-block copolymer showed temperature-sensitive sol-gel transition behavior. Over specific concentration, the whole system cannot flow by the packing of micelles. However, with increasing temperature, packing structure was destroyed by the decrease of the micelle volume due to the dehydration and contraction of the PEO chain, and the system flew. In the sol-gel transition phase diagram obtained by the vial tilting method, the critical gel concentration decreased, the boundary curve shifted to the left, and the gel regions were expanded with increasing the molecular weight of PLLA block and PEO block
Sol-gel transition behavior of biodegradable three-arm and four-arm star-shaped PLGA-PEG block copolymer aqueous solution
No full textTwo types of temperature-sensitive biodegradable three-arm and four-arm star-shaped poly(DL-lactic acid-co-glycolic acid-b-ethylene glycol) (3-arm and 4-arm PLGA-PEG) were successfully synthesized via the coupling reaction of 3-arm and 4-arm PLGA and alpha-monocarboxyl-omega-monomethoxypoly(ethylene glycol) (CMPEG), In dilute aqueous solutions, star PLGA-PEGs showed the temperature- and concentration-dependent formation and aggregation of micelles over specific concentration and specific temperature. With increasing the molecular weight and the relative hydrophobicity of hydrophobic PLGA block, critical micelle temperature (CMT) decreased, Aqueous solution of 4-arm PLGA-PEG started to form micelles at lower, temperature and showed sharper temperature-dependent growth in micelle size. These results are due to the enhanced hydrophobicity of PLGA block. On the other hand, at high concentration, two types of 3-arm and 4-arm PLGA-PEG showed sol-gel-sol transition behavior as the temperature was increased. The 3-arm and 4-arm PLGA-PEG Showed sol-gel transition at higher polymer concentrations (above 24 wt %) than the PEG-PLGA-PEG triblock copolymer. As the molecular weight and the relative hydrophobicity of PLGA block increased, the critical gel concentration (CGC) decreased. (c) 2005 Wiley Periodicals, Inc
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
Synthesis, characterization and protein adsorption behaviors of PLGA/PEG di-block co-polymer blend films
No full textA series of poly(D,L-lactic-co-glycolic acid) (PLGA)/poly(ethyleneglycol) (PEG) di-block copolymers were synthesized by ring-opening polymerization of D,L-lactide and glycolide with different molecular weights of monomethoxy polyethyleneglycol (mPEG) 750, 2000 and 5000 as an initiator. The bulk properties of these co-polymers were characterized by using H-1 NMR spectroscopy, gel permeation chromatography, differential scanning calorimetry (DSC). Electron spectroscopy for chemical analysis (ESCA) results, in which the blend films with the di-block copolymers showed increasing surface oxygen atomic percentage with increasing PEG chain length, indicate that PEG chain segment in the di-block copolymers is surface oriented and enriched onto the surface of the blend films. The extent of protein adsorption onto the surface of these blend films was studied, using iodine radio-labeled human serum albumin, gamma globulin and human growth hormone. The protein adsorption amount was reduced for the blend films prepared with PLGA/PEG 750 and 2000 di-block copolymers, but increased to a great extent for PLCA/PEG 5000 di-block copolymer. This is due to the increased water uptake capacity of the blend film, which absorbed more protein molecules into a swollen polymer matrix in addition to surface adsorption. (C) 2000 Elsevier Science B.V. All rights reserved.the research
grant from the Center for Advanced Functional
Polymers of KAIST, which was funded
from KOSEF.
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
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