1,720,977 research outputs found
MACROALGA EXTRACT EFFECT’S ON BIOCHEMICAL RESPONSES OF SEA URCHINS ARBACIA LIXULA (Linnaeus, 1758)
No full textMarine algae produce important secondary metabolites that vary between the different species, spatial distribution and the seasonal period. The production of these secondary metabolites by macroalgae allows to protect themselves from environmental stress conditions (competitors, pathogens, grazers, epiphytes). Several studies report different biological properties of the extracts or molecules obtained from these macroalgae such us: immunomodulatory (RAPOSO et al., 2016), antioxidant (FISCH et al., 2003), anticancer (ABU-KHUDIR et al., 2021) and antimicrobial (PINTEUS et al., 2015).
In light of that, the aim of this study was to evaluate the effect of extract the macroalga Ericaria crinita (J. Agardh, Molinari and Guiry, 2020), on the innate immune system of sea urchin A. lixula. The animals were in vivo treated with macroalgae extract and the effects were analysed after three hours sampling coelomic fluid in which total cells counts were evaluated. Then, the cells were separated from cell free. On cellular lysate and on cell free protein concentration, enzyme activity and antioxidant responses (inhibition of oxidative stress through the evaluation of reactive oxygen/nitrogen species (RONS) and glutathione (GSH) levels) were evaluated. Our results showed important changes in enzymatic activities and decrease in the inflammatory marker nitric oxide (NO). Further studies are needed to better understand the action of these bioactive molecules however, these results are certainly encouraging and prompt us to investigate the potential use that can be made of these compounds produced by macroalgae in the bio-medical and industrial fields
CHEMICAL CHARACTERIZATION AND BIOLOGICAL PROPERTIES OF MACROALGAE EXTRACTS
No full textMarine species are a rich source of bioactive molecules and among them, it is known that marine algae produce different secondary metabolites for which different biological activities such as: immunomodulatory (Raposo et al., 2016), antioxidant (Fisch et al., 2003) and antimicrobial (Pinteus et al., 2015) were demostrated. The aim of this study was chemical charac- terize the extracts of three macroalgae species: Carpodesmia crinite (Duby, Orellana & Sansón, 2019), Carpodesmia brachy- carpa (J. Agardh, Orellana & Sansón 2019, WoRMS, 2023), Ericaria brachycarpa (J. Agardh, Molinari & Guiry, 2020), Asparagopsis taxiformis (Delile) Trevisan 1845) to evaluate also their biological activities. The characterization of the secondary metabolites was performed by HPLC-MS and showed higher meroterpenoids levels. Then, the extracts were tested on the Arbacia lixula sea urchin and against the bacterial strains Listeria monocytogenes and Staphylococcus aureus. In the first case results showed a modulation in total and differential cell count demonstrating their involvement in immunity responses. In the second case important antimicrobial activities were observed against both bacterial strains tested. The results obtained, although preliminary, are certainly encouraging to understand better the biological potentiality of these metabolites
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
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
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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