1,720,988 research outputs found
Screening, identification and biochemical, molecular and structural characterisation of microbial lipases, phospholipases and proteases of industrial interest
No full textCette étude présente une nouvelle enzyme lipolytique de la famille des (phospho)lipases, produite par la souche fongique Fusarium annulatum Bugnicourt nouvellement isolée. L'enzyme purifiée présente une activité spécifique élevée à la fois sur les triglycérides (3500 U/mg sur TC8) et sur les phospholipides (5000 U/mg sur le PC de jaune d'œuf). Une fois caractérisée, cette lipase, nommée FAL, a démontré une activité élevée sur une large gamme de pH et à des températures relativement élevées, ainsi qu'une stabilité alcaline significative, ce qui est rare chez les lipases fongiques. De plus, cette lipase alcaline semble être une candidate parfaite pour une application dans la détergence puisqu'elle a montré une remarquable stabilité en présence de tensioactifs non ioniques, d'agents oxydants, de produits de blanchiment et de divers détergents liquides et solides. Dans le cadre de cette étude, un gène codant pour une autre lipase de Fusarium annulatum a été cloné dans Pichia pastoris et purifié en une quantité importante (210 mg L-1). L'enzyme purifiée a également montré une activité spécifique élevée envers les triglycérides (6000 U/mg sur TC8) et les phospholipides (6500 U/mg sur le PC de jaune d'œuf). Les résultats du dichroïsme circulaire ont également révélé que la lipase recombinante (rFAL) maintient une bonne stabilité à des températures élevées, à des pH alcalins et en présence de solvants polaires. Les expériences de docking moléculaire in silico ont révélé que les triglycérides et les phospholipides s'ajustent bien dans le site actif de rFAL, avec une orientation favorisant la régiospécificité sn-1, en accord avec les expériences in vitro. Nos analyses structurales démontrent le rôle crucial du C-terminal dans l'expression de l'activité phospholipase de cette enzyme.This study presents a new lipolytic enzyme from the (phospho)lipase family, produced by the newly isolated fungal strain Fusarium annulatum Bugnicourt. The purified enzyme exhibits a high specific activity on both triglycerides (3500 U/mg on TC8) and phospholipids (5000 U/mg on egg yolk PC). Once characterized, this lipase, named FAL, demonstrated high activity over a wide pH range and at relatively high temperatures, as well as significant alkaline stability, which is rare among fungal lipases. Furthermore, this alkaline lipase appears to be a perfect candidate for detergent applications, as it has shown remarkable stability in the presence of non-ionic surfactants, oxidizing agents, bleaching products, and various liquid and solid detergents. A gene encoding another lipase from Fusarium annulatum was successfully cloned into Pichia pastoris and purified in a significant quantity (210 mg L-1). The purified enzyme also exhibited high specific activity towards triglycerides (6000 U/mg on TC8) and phospholipids (6500 U/mg on egg yolk PC). Circular dichroism results revealed that the recombinant lipase (rFAL) maintains good stability at high temperatures, alkaline pH, and in the presence of polar solvents. Molecular docking experiments in silico demonstrated a favorable binding of triglycerides and phospholipids to the active site of rFAL, with an orientation that favors sn-1 regiospecificity, consistent with in vitro experiments. Our structural analyses demonstrate the crucial role of the C-terminal in the expression of phospholipase activity in this enzyme
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
Sustainable removal of arsenic from waters by adsorption on blue crab, Portunus segnis (Forskål, 1775) chitosan-based adsorbents
No full textAuthor-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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