1,720,967 research outputs found
A maize endosperm-specific promoter can be used as a general purpose promoter for high level gene expression in plants
No full textTransient β-glucuronidase (GUS) expression was utilized to test the strength of a novel promoter system based on the maize (Zea mays) endosperm- specific b-32 gene promoter and its physiological activation Opaque 2 (O2). Up to ten O2 binding sites were taken together in the same promoter either separately, or in combination with the CaMV (Cauliflower Mosaic Virus) 35S promoter. The efficiency of the double component system has been tested versus a construct bearing the CaMV promoter coupled with GUS gene, in which the sequences surrounding the ATG were modified to fit an optimal translation start for eukaryotes. Data presented indicate that b-32 promoter, driven by the Opaque-2 protein, might be a good choice for gene expression in plants
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
Maize Histone Deacetylase hda101 Is Involved in Plant Development, Gene Transcription, and Sequence-Specific Modulation of Histone Modification of Genes and Repeats
Get PDFEnzymes catalyzing histone acetylation and deacetylation contribute to the modulation of chromatin structure, thus playing
an important role in regulating gene and genome activity. We showed that downregulation and overexpression of the maize
(Zea mays) Rpd3-type hda101 histone deacetylase gene induced morphological and developmental defects. Total levels of
acetylated histones and histone acetylation of both repetitive and nonrepetitive sequences were affected in hda101
transgenic mutants. However, only transcript levels of genes but not repeats were altered. In particular, hda101 transgenic
mutants showed differential expression of genes involved in vegetative-to-reproductive transition, such as liguleless2 and
knotted-like genes and their repressor rough sheath2, which are required for meristem initiation and maintenance.
Perturbation of hda101 expression also affected histone modifications other than acetylation, including histone H3
dimethylation at Lys-4 and Lys-9 and phosphorylation at Ser-10. Our results indicate that hda101 affects gene transcription
and provide evidence of its involvement in setting the histone code, thus mediating developmental programs. Possible
functional differences between maize hda101 and its Arabidopsis thaliana ortholog HDA19 are discussed
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