1,721,024 research outputs found
Acute effects of aflatoxins on guinea pig ileum
No full textPrevious studies on the aflatoxins have focused mainly on their chronic toxic effects. In this study we investigated the acute gastrointestinal effects of four common aflatoxins on isolated guinea pig ileum. AFB(1) (EC(50) 4.6+/-0.4 microM) and AFB(2) (EC(50)17+/-4.4 microM) contracted isolated guinea pig ileum in a dose-dependent manner, whereas AFG(1) and AFG(2) evoked no contractions. Atropine (5.9 nM 11.8 and 23.6 nM) antagonized AFB(1)-induced contractions in a dose-dependent manner. Pretreatment with the nicotinic ganglionic blocker, hexamethonium (up to 55 microM), left AFB(1)-induced contractions unchanged. In contrast, tetrodotoxin (0.3 microM), blocked AFB(1) contractile activity. The two inhibitors of ACh release, morphine (0.3 microM) and clonidine (0.4 microM), antagonized EC(50) AFB(1)-induced contractions, and apamin, a drug that increases neuronal excitability, facilitated the EC(50) AFB(1)-induced contractile effect. The choline uptake blocker, hemicholinium (17.4 microM) markedly reduced AFB(1)-induced contractions. These results suggest that aflatoxins induce their contractile effect indirectly through the cholinergic system by stimulating acetylcholine release from the postganglionic parasympathetic nerve endings. The acute actions of aflatoxins on isolated guinea pig ileum could explain their acute gastrointestinal effects in humans and animals
Da Dante a Luzi sulle tracce del divino
Full text linkIl saggio offre un’interessante riflessione sull’ultimo volume di Michele Bianco, “Lev Shomeà (I RE 3,9) «Un cuore ascoltante». Da Dante a Luzi. Epifania del divino, ierofania e amor di Patria”, che presenta un’analisi su autori e momenti significativi della nostra tradizione letteraria. Bianco disegna, attraverso 17 densi saggi, un affresco della nostra storia letteraria, filtrato nell’ottica di una visione rinnovata del mondo della fede, intesa sia come epifania del divino, in autori dichiaratamente credenti (Dante, Petrarca, Luzi), sia come ierofania in autori (come d’Annunzio, Pirandello o Pasolini), aperti a un totalmente ‘Altro’, inteso come Oltre, e dove ‘la parola che si ascolta’ diventa quel filo conduttore, utile a superare l’eterogeneità degli autori trattati, in nome di quella visione rinnovata del mondo della fede che dà senso e unità a questo volume.In this essay, the author provides us with some interesting reflections on the challenging work resulted in the last volume written by Michele Bianco ((‘Lev Shomeá (‘I RE 3,9’) “Un cuore ascoltante”. Da Date a Luzi. Epifania del divino, ierofania e amor di Patria’). The essay is an accurate analysis of different authors and significant eventsof our literary tradition, combining, within a non-specialised concept of knowledge, the contributions of formalism, of the Prague Linguistic Circle, and structural linguistics, with the legacies of the best hermeneutic tradition of the 20th century (Heidegger and Gadamer): The scholar focuses on two fundamental issues. The first one is related to the methodologyderiving, as the title highlights, from shomeá, in other words from the humble approach, from the welcoming, listening attitude of the hermit priest in his/her journey towards knowledge. The other issue deals specifically with the main topic, trying to find that unifying element which could guide the reader through this complex research. In his 17 datailed essays, the author offer us a great, powerful overview of our literary history, in a renewed prespective on the world of faith, both as Divine Epiphany (such as that found in the works by authors who werw declared believer, like Dante, Petrarca luzi) and as Hierophany (such as that foubd in the works by D’Annunzio, Pirandello or Pasolini, who werw open to something which is totally “Other’, meaning “Beyond”), and where ‘the word that you listen to’ becomes the common thread, thanks to which you can overcome the heterogeneity of the authors treated, in the name of that renewed prspective on the world of faith gives meaning and unity to this volume
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
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