1,720,958 research outputs found
Rational Design, Synthesis and Biological Evaluation of Bis(pyrimido[5,6,1-de]acridines) and Bis(pyrazolo[3,4,5-kl]acridine-5-carboxamides) as New Anticancer Agents
No full textThe good results obtained with pyrimido[5,6,1-de]acridines 7 and with pyrazolo[3,4,5-kl]-acridinecarboxamides 8 prompted us to the synthesis of two new series of his acridine derivatives: the bis(pyrimidoacridines) 5 and the bis(pyrazoloacridinecarboxamides) 6. Compounds 5 can be regarded also as cyclized derivatives of bis(acridine-4-carboxamides) 3 and compounds 6 as cyclized derivatives of bis(acridine-4-carboxamides) 4. The noncovalent DNA-binding properties of these compounds have been examined using fluorometric techniques. The results indicate that (i) the target compounds are excellent DNA ligands; (ii) the his derivatives 5 and 6 are more DNA-affinic than corresponding monomers 7 and 8; (iii) the new bis 5 and 6 result always less efficient in binding than related bis(acridine-4-carboxamides) 3 and 4; and GO in both series 5 and 6 a clear, remarkable in some cases, preference for binding to AT rich duplexes can be noted. In vitro cytotoxic potency of these derivatives toward the human colon adenocarcinoma cell line (HT29) is described and compared to that of reference drugs. Structure- activity relationships are discussed. We could identify six very potent cytotoxic compounds for further in vitro studies: a cytotoxic screening against six human cancer cell lines and the National Cancer Institute (NCI) screening on 60 human tumor cell lines. Finally, compound 6a was selected for evaluation in a NCI in vivo hollow fiber assay
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
Synthesis and biological evaluation of new asymmetrical bisintercalators as potential antitumor drugs
No full textThe good results obtained in the past decade with various types of potential bisintercalating agents, e. g., LU 79553, DMP 840, BisBFI, MCI3335, WMC-26, BisAC, BisPA, and the asymmetrical derivative WMC-79 ( Chart 1), prompted us to investigate a new series of asymmetrical bisintercalators, compounds 1a-t ( Chart 2), which can combine the potentiality of bisintercalation with a possible different mechanism of action due to two diverse chromophores. The DNA-binding properties of these compounds have been examined using fluorometric techniques: target compounds are excellent DNA ligands, with a clear preference for binding to AT-rich duplexes. In vitro cytotoxicity of these derivatives toward human hormone-refractory prostate adenocarcinoma cell line (PC-3) is described. Apoptosis assays of four selected compounds are also reported. Very potent cytotoxic compounds, some of them capable of inducing early apoptosis, have been identified
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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