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Nouvelles approches pour la détection fluorescente et/ou chromogénique des ions cyanures. Applications aux analyses environnementales sur site et à la détection sélective du neurotoxique organophosphoré tabun.
No full textEnvironmental pollution by cyanides and organic cyanide compounds is still a very current issue. Indeed, their use in several sectors of industry is indispensable but these activities (even if they are theoretically carried out within a well-defined regulatory framework) combined with deviant behaviour (e.g., voluntary discharges, chemical terrorism) pose heavy threats to humans, groundwater and ecosystems. Therefore, the detection and measurement of these toxic pollutants are regularly carried out to verify that their levels are below those set by national legislation and/or international standards. Access to efficient, easy-to-use and inexpensive environmental analysis equipment is therefore essential. In this context, this thesis project aims to develop an innovative fluorescent chemodosimeter selective towards cyanide ions to meet two objectives: (1) the detection of cyanide ions in environmental matrices using a simple "mix & read" approach, suitable for on-site analysis, and (2) the selective detection of the nerve agent Tabun and discriminating against other organophosphorus nerve agents. This manuscript describes the synthesis and in vitro validations of conventional fluorogenic probes (chapter I) and "covalent-assembly" probes whose activation by cyanides leads to in situ formation of a pyronine dye (chapter II). The development of a "mix & read" analysis method, as well as the validation of the "covalent-assembly" chemodosimeters through the use of portable fluorometers adapted to our protocol are also covered. (chapter III). Finally, the indirect detection of a tabun mimic (DCNP) by means of our chemodosimeters (i.e. conventional and "covalent-assembly") is described (chapter IV). This last part is also completed by a multiplex detection study of tabun and VX mimics (DCNP and PhX).Keywords: chemodosimeter; "covalent-assembly"; cyanide; domino reaction; environmental analysis; multiplexed detection; ; on-site detection; organophosphorus nerve agent; portable fluorometer; pyronin dye; tabun.La pollution de l'environnement par les cyanures et les composés cyanés organiques est une problématique toujours très actuelle. En effet, leur utilisation dans plusieurs secteurs de l'industrie est indispensable mais ces activités (même si elles sont théoriquement menées dans un cadre réglementaire bien défini) combinées à des comportements déviants (e.g., rejets volontaires, terrorisme chimique) font peser de lourdes menaces sur l'Homme, les nappes phréatiques et les écosystèmes. Ainsi, la détection et le dosage de ces polluants toxiques sont régulièrement réalisés en utilisant des techniques analytiques efficaces mais pas nécessairement bien adaptées à des analyses directement sur site. Il y a donc un réel intérêt à développer de nouvelles approches de détection des ions cyanures, faciles à mettre en œuvre et tirant parti des multiples avantages de la spectroscopie de fluorescence. C'est dans ce contexte que s'inscrit cette thèse qui a pour but de mettre au point un système innovant de détection moléculaire par fluorescence des ions cyanures pour répondre à deux objectifs, (1) la détection des ions cyanures dans des matrices environnementales selon une méthodologie simple, de type "mix & read", adaptée à l'analyse sur site, et (2) la détection sélective du neurotoxique tabun et discriminante des autres neurotoxiques organophosphorés. Ce manuscrit décrit les synthèses et validations in vitro de sondes fluorogéniques dites conventionnelles (chapitre I) et de type "covalent-assembly" dont l'activation par les cyanures conduit à la formation in situ d'un colorant pyronine (chapitre II). Le développement d'une méthode d'analyse de type "mix & read", ainsi que la validation des chemodosimètres "covalent-assembly" via l'usage de fluorimétres portatifs adapté à notre protocole sont également traités (chapitre III). Enfin, la détection indirecte d'un analogue du tabun (DCNP) par nos différents systèmes de détection (i.e. conventionnels et "covalent-assembly") est décrite (chapitre IV). Cette dernière partie est également complétée par une étude de détection multiplexe des analogues du tabun (DCNP) et du VX (PhX).Mots-clés : agent innervant organophosphoré ; analyse environnementale ; assemblage covalent ; chemodosimètre fluorescent ; colorant pyronine ; cyanure ; détection multiplexe ; détection sur site ; fluorimétre portable ; réaction domino; tabun
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
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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