1,720,982 research outputs found
Antioxidant activity and phenolic profiles of wild currant Ribes magellanicum from Chilean and Argentinian Patagonia
No full textThe Patagonian currant Ribes magellanicum is highly valued due to its pleasantflavor and sweet taste. The aim of this study was to characterize its constituentsand to assess their antioxidant and cytoprotective properties. For the fruitphenolic-enrichedextract (PEE), total phenolics (TP), total flavonoids (TF), andantioxidant activity (DPPH, Ferric reducing antioxidant power (FRAP), andTrolox equivalent antioxidant activity (TEAC)) were determined. Argentineansamples presented better activity in the DPPH and FRAP assays. Best cytoprotectionagainst oxidative stress induced by H2O2 in AGS cells was found in oneArgentinean sample at 500 μg mL−1 (65.7%). HPLC MS/MS analysis allowedthe tentative identification of 59 constituents, including eight anthocyanins, 11conjugates of caffeic-,ferulic-,and coumaric acid, and 38 flavonoids, most ofthem quercetin and kaempferol derivatives. Argentinean samples showed a morecomplex pattern of anthocyanins, hydroxycinnamic acids (HCA), and flavonoids.Cyanidin rhamnoside hexoside and cyanidin hexoside were the main anthocyanins,accounting for 35 and 55% for the Argentinean and 60 and 27% for theripe Chilean fruits. HCA content was about three times higher in Argentineansamples. The phenolic profiles of Chilean and Argentinean Ribes magellanicumshow remarkable differences in chemical composition with higher HCA andflavonoid content in Argentinean samples.Fil: Jimenez Aspee, Felipe. Universidad de Talca; ChileFil: Tomas Valdez, Samanta. Universidad de Talca; ChileFil: Schulz, Ayla. Universidad de Talca; ChileFil: Ladio, Ana Haydee. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Patagonia Norte. Instituto de Investigación En Biodiversidad y Medioambiente; Argentina. Universidad Nacional del Comahue; ArgentinaFil: Theoduloz, Cristina. Universidad de Talca; ChileFil: Schmeda Hirschmann, Guillermo. Universidad de Talca; Chil
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
Inhibition of key enzymes in the inflammatory pathway by hybrid molecules of terpenes and synthetic drugs: In vitro and in silico studies
Get PDFThe aim of this work was to compare the anti-inflammatory activity of compounds prepared from terpenes and the synthetic drugs ibuprofen and naproxen. The anti-inflammatory activity of the hybrid compounds was compared with the activity of the parent compounds. This was accomplished using in vitro inhibition of lipoxygenases (LOX) and COX-2, and in silico docking studies in 15-LOX and COX-2. The synthesized hybrids showed an inhibition of COX-2 and LOX between 9.8%–57.4% and 0.0%–97.7%, respectively. None of the hybrids showed an improvement in the inhibitory effect toward these pro-inflammatory enzymes, compared to the parent terpenes and non-steroidal anti-inflammatory drugs. The docking studies allowed us to predict the potential binding modes of hybrids 6–15 within COX-2 and 15-LOX active sites. The relative affinity of the compounds inside the binding sites could be explained by forming non-covalent interactions with most important and known amino acids reported for those enzymes. A good correlation (r 2 = 0.745) between docking energies and inhibition percentages against COX-2 was found. The high inhibition obtained for compound 10 against COX-2 was explained by hydrogen bond interactions at the enzyme binding site. New synthetic possibilities could be obtained from our in silico models, improving the potency of these hybrid compounds.Fil: Theoduloz, Cristina. Universidad de Talca; ChileFil: Alzate-Morales, Jans. Universidad de Talca; ChileFil: Jiménez-Aspee, Felipe. Universidad de Talca; ChileFil: Isla, Maria Ines. Universidad Nacional de Tucumán; Argentina. INBIOFIV; ArgentinaFil: Alberto, Maria Rosa. Universidad Nacional de Tucumán; ArgentinaFil: Pertino, Mariano Walter. Universidad de Talca; ChileFil: Schmeda-Hirschmann, Guillermo. Universidad de Talca; Chil
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
Anti-Inflammatory Activity of Copao (Eulychnia Acida Phil., Cactaceae) Fruits
Get PDFCopao (Eulychnia acida Phil., Cactaceae) is an endemic species occurring in northern Chile. The edible fruits of this plant are valued for its acidic and refreshing taste. Phenolic-enriched extracts from copao fruit pulp and epicarp, collected in the Elqui and Limari river valleys, were assessed by its in vitro ability to inhibit the pro-inflammatory enzymes lipoxygenase (LOX) and cyclooxygenases (COX-1 and COX-2). At 100 μg/mL, pulp extracts showed better effect towards LOX than epicarp extract, while COX-2 inhibition was observed for both epicarp and pulp samples. In general, the extracts were inactive towards COX-1. A positive correlation was observed between the anti-inflammatory activity and the main phenolic compounds found in this fruit. Copao fruits from the Limari valley, a main place of collection and commercialization, showed major activity, adding evidence on the possible health-beneficial effects of this native Chilean fruit.Fil: Jiménez Aspee, Felipe. Universidad de Talca; ChileFil: Alberto, Maria Rosa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Instituto de Quimica del Noroeste; ArgentinaFil: Quispe, Cristina. Universidad de Talca; ChileFil: Caramantin Soriano, Maria del Pilar. Universidad de Talca; ChileFil: Theoduloz, Cristina. Universidad de Talca; ChileFil: Zampini, Iris Catiana. Universidad de Talca; Chile. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Instituto de Quimica del Noroeste; ArgentinaFil: Isla, Maria Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Instituto de Quimica del Noroeste; ArgentinaFil: Schmeda Hirschmann, Guillermo. Universidad de Talca; Chil
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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