1,721,018 research outputs found
Alu RNA transcribed in vitro binds the 68-kDa subunit of the signal recognition particle
Get PDFAntibodies directed against the 68-kDa subunit of signal recognition particle (SRP) precipitate an Alu RNA X protein complex formed during in vitro transcription of a plasmid containing an Alu family sequence. The same Alu RNA X protein complex is precipitated by anti-Alu sera from certain patients with systemic lupus erythematosus and related autoimmune diseases (Kole, R., Fresco, L. D., Keene, J. D., Cohen, P. L., Eisenberg, R. A., and Andrews, P. G. (1985) J. Biol. Chem. 260, 11781-11786). Similarly to anti-SRP antibodies human, anti-Alu sera precipitate SRP from HeLa cell extract and detect a 68-kDa SRP subunit on immunoblots. These results indicate that the Alu antigen and the 68-kDa SRP subunit are the same polypeptide
Temperature-dependent splicing of beta-globin pre-mRNA
No full textA T-->G mutation at nucleotide 705 of human beta-globin intron 2 creates an aberrant 5' splice site and activates a cryptic 3' splice site upstream. In consequence, the pre-mRNA is spliced via aberrant splice sites, despite the presence of the still functional correct sites. Surprisingly, when IVS2-705 HeLa or K562 cells were cultured at temperatures below 30 degrees C, aberrant splicing was inhibited and correct splicing was restored. Similar temperature effects were seen for another beta-globin pre-mRNA, IVS2-745, and in a construct in which a beta-globin intron was inserted into a coding sequence of EGFP. Temperature-induced alternative splicing was affected by the nature of the internal aberrant splice sites flanking the correct sites and by exonic sequences. The results indicate that in the context of thalassemic splicing mutations and possibly in other alternatively spliced pre-mRNAs, temperature is one of the parameters that affect splice site selection
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
Spontaneous and MNNG-induced reversion of an EGFP construct in HeLa cells: an assay for observing mutations in living cells by fluorescent microscopy
No full textA HeLa cell line stably expressing the enhanced green fluorescence protein (EGFP) gene, interrupted by the HBB IVS2-654 intron, was studied without treatment and after treatment with a single standard dose of 15 microM of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). This assay was done in order to prove that such a construct can revert by a variety of mechanisms and that it produces a visible phenotype, i.e., green fluorescence. The system permits visual detection of living mutant cells among a background of non-mutant cells and does not require a selective medium. The results show that the construct reverts by large deletions (-62, -100, and -162 bp), small insertions (+4 bp), small rearrangements (19 bp duplication), base substitutions at purines (G652, G653, A655, G579), and a pyrimidine (T654) between nucleotide positions 579 and 837. Splice-site mutations were recovered, and some of the mechanisms underlying these mutations are discussed. Because of the ease of detection of revertant cells under fluorescent light and the wide variety of mutations that can be recovered, further development of this system could make it a useful new mammalian cell mutagenicity assay
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
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