1,720,955 research outputs found
Spectroscopic Study of miRNA Structure and Interactions
No full textMiRNA are short RNA molecules that mediate post-transcriptional regulation of gene expression by binding to a target mRNA. In this thesis, some structural properties and thermodynamic parameters (melting temperature, enthalpy ∆H and entropy ∆S changes connected with the transition between particular conformations) of oligonucleotides simulating complex of miRNA and mRNA, were characterized by using spectroscopic methods and a gel electrophoresis. Temperature dependences of UV and Raman spectra were measured, the results treated by means of a factor analysis, and the abovementioned thermodynamic parameters determined by a fit to a feasible model. The outputs have demonstrated the capability of the used methods to determine thermodynamic and structural properties of non-canonical RNA complexes. Powered by TCPDF (www.tcpdf.org
miRNA complexes with the target RNA sequence
No full textmiRNAs are short non-coding RNA molecules which play role in post-transcriptional regulation of gene expression. Thus, miRNAs are related to a variety of physiological processes and diseases, e.g. some tumours or viral infections. In this diploma thesis we studied temperature-induced dissociation of complexes that simulated pairing of miRNA with target mRNA. For these purposes we used UV absorption spectroscopy and Raman spectroscopy. Measured spectra were then treated by means of a factor analysis. The aim of the thesis was to determine thermodynamic parameters of the complexes dissociation and to clarify how inner loops and bulges affect the stability of oligonucleotide duplexes. Also, we have tested the suitability of the used approach for study of oligonucleotide complexes. We have shown that factor analysis of temperature dependent UV absorption spectra is a proper base to determine thermodynamic parameters of the duplex dissociation. Raman spectra were affected by large errors, nevertheless they enabled to observe some structural changes related to the transition. It has been shown that the bulge loop present in the studied complex reduces both its flexibility and the energetic preference of its formation
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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