1,720,968 research outputs found
Full-length single-walled carbon nanotubes decorated with streptavidin-conjugated quantum dots as multivalent intracellular fluorescent nanoprobes
No full textWe report the formation of a supramolecular luminescent nanoassembly composed of individual or small ropes of full-length, single-walled carbon nanotubes decorated with streptavidin-conjugated quantum dots. The supramolecular luminescent nanoassembly was stably dispersed under physiological conditions and was readily visible by both optical and confocal fluorescent microscopies. Jurkat T leukemia cells were able to internalize the nanoassembly by multivalent CD3 receptor-mediated endocytosis (adsorption by cell). Once internalized by cells, the nanoassembly was found to be transported to lysosomes. These properties should make this supramolecular luminescent nanoassembly an excellent building block for the construction of intracellular polyvalent nanoprobes, mimicking natural viral delivery entities with enhanced loading capacity compared to small molecules
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Adsorption of streptavidin onto single-walled carbon nanotubes: application in fluorescent supramolecular nanoassemblies
No full textWe report the solubilization of full-length single-walled carbon nanotubes into a physiological buffer by sonication in presence of streptavidin. Transmission electron microscopy showed that the resultant dispersion was enriched of individual/small ropes of nanotubes. By the analysis of the crystal structure of tetrameric streptavidin and of the tryptophan emission of adsorbed proteins we hypothesized that proteins adsorbed onto SWNT sidewalls through their amine functionalities. Our results suggested using streptavidin as an interlinker between carbon nanotubes and semiconducting nanocrystals. We fabricated a supramolecular luminescent nanoassembly composed of individual or small ropes of full-length single-walled carbon nanotubes decorated with streptavidin-conjugated quantum dots. The luminescent nanoassembly was stably dispersed under physiological conditions and was readily visible by optical fluorescent microscopies
Variations on the Author
Full text link“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
Full text linkWe 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
High mobility group Al is a molecular target for MYCN in human neuroblastoma
No full textHigh mobility group A1 (HMGA1) is an architectural transcription factor and a putative protoncogene. Deregulation of its expression has been shown in most human cancers. We have previously shown that the expression of the HMGA family members is deregulated in neuroblastoma cell lines and primary tumors. On retinoic acid (RA) treatment of MYCN-amplified neuroblastoma cell lines, HMGA1 decreases with a kinetics that strictly follows MYCN repression. In addition, MYCN constitutive expression abolishes HMGA1 repression by RA. Here we explored the possibility that HMGA1 expression might be sustained by MYCN in amplified cells. Indeed, MYCN transfection induced HMGA1 expression in several neuroblastoma cell lines. HMGA1 expression increased in a transgene dose-dependent fashion in neuroblastoma-like tumors of MYCN transgenic mice. In addition, it was significantly more expressed in MYCN-amplified compared with MYCN single-copy primary human neuroblastomas. MYCN cotransfection activated a promoter/luciferase reporter containing a 1,600 bp region surrounding the first three transcription start sites of the human HMGA1 and eight imperfect E-boxes. By heterodimerizing with its partner MAX, MYCN could bind to multiple DNA fragments within the 1,600 bp. Either 5' or 3' deletion variants of the 1,600 bp promoter/luciferase reporter strongly decreased luciferase activity, suggesting that, more than a single site, the cooperative function of multiple cis-acting elements mediates direct HMGA1 transactivation by MYCN. Finally, HMGA1 repression by RNA interference reduced neuroblastoma cell proliferation, indicating that HMGA1 is a novel MYCN target gene relevant for neuroblastoma tumorigenesis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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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