1,720,962 research outputs found
Binding of Epstein-Barr virus nuclear antigen 1 to DNA: inhibition by distamycin and two novel distamycin analogues
No full textModulation of the interaction between cellular or viral transcription factors and target DNA sequences may represent a potential experimental strategy to control proliferation of neoplastic cells as well as virus DNA replication. Distamycin represents a likely candidate to mediate such modulation by pharmacological means. In order to obtain more detailed information on structure-activity relationships of these compounds, we have analysed the effects of distamycin and two distamycin analogues on the binding of a recombinant protein, the Epstein-Barr virus nuclear antigen 1 (EBNA-1) to its target sequence of Epstein-Barr virus, containing the 12 bp palindromic consensus TAGCATATGCTA. The sequence selectivity in the binding of distamycin to DNA was evaluated by footprinting experiments, while the effects of distamycins on DNA-protein interactions was analysed by means of electrophoretic mobility shift assay. The data presented in this paper suggest that distamycin and its analogues differentially inhibit the interaction between DNA-binding proteins and target DNA sequences
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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
Oxidative degradation of cardiotoxic anticancer anthracyclines to phthalic acids: novel function for ferrylmyoglobin.
Get PDFWe show that the pseudoperoxidase activity of ferrylmyoglobin(MbIV) promotes oxidative degradation ofdoxorubicin (DOX), an anticancer anthracycline knownto induce severe cardiotoxicity. MbIV, formed in vitro byreacting horse heart MbIII with H2O2, caused disappearanceof the spectrum of DOX at 477 nm and appearanceof UV-absorbing chromophores that indicated openingand degradation of its tetracyclic ring. Electron sprayionization mass spectrometry analyses of DOX/MbIV ultrafiltratesshowed that DOX degradation resulted information of 3-methoxyphthalic acid, the product of oxidativemodifications of its methoxy-substituted ring D.Other methoxy-substituted anthracyclines similarly released3-methoxyphthalic acid after oxidation by MbIV,whereas demethoxy analogs released simple phthalicacid. Kinetic and stoichiometric analyses of reactionsbetween DOX and MbIII/H2O2 or hemin/H2O2 showedthat the porphyrin radical of MbIV-compound I and theiron-oxo moiety of MbIV-compound II were sequentiallyinvolved in oxidizing DOX; however, oxidation by compoundI formed more 3-methoxyphthalic acid than oxidationby compound II. Sizeable amounts of 3-methoxyphthalicacid were formed in the heart of micetreated with DOX, in human myocardial biopsies exposedto DOX in vitro, and in human cardiac cytosol thatoxidized DOX after activation of its endogenous myoglobinby H2O2. Importantly, H9c2 cardiomyocytes weredamaged by low concentrations of DOX but could tolerateconcentrations of 3-methoxyphthalic acid higherthan those measured in murine or human myocardium.These results unravel a novel function for MbIV in theoxidative degradation of anthracyclines to phthalic acidsand suggest that this may serve a salvage pathwayagainst cardiotoxicity
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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