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Strategies adaptatives de deux especes du genre pistacia (p. lentiscus l. et p. atlentica desf.) aux conditions d'altitude, de salinite et d'aridite: [texte imprimé] : approches morpho- anatomiques, phytochimiques et ecophysiologiques
No full text160F.; 30cm. (+ CD-ROM)ont les plus abondantes et vivant à l’état sauvage en Algérie dans des milieux très
contrastés. Une meilleure connaissance de leur adaptation en milieu naturel serait certainement
d’un grand intérêt pour la réussite du programme de reboisement en Algérie.
Notre étude consiste donc à comprendre les stratégies développées par ces deux espèces dans des
habitats aux conditions extrêmes, notamment l’altitude, l’aridité et la salinité et ceci, en se basant
sur les aspects morpho-anatomiques, phytochimiques et écophysiologiques.
Une première étude réalisée in situ a permis de mettre en évidence, la variabilité de trois
populations algériennes de pistachier de l’Atlas (Béchar, Laghouat et Médéa) en relation avec la
sécheresse. Cette étude a montré une grande plasticité des caractères morpho-anatomiques et
phytochimiques. L’adaptation ou l’accommodation à l’aridité s’expliquerait par une
augmentation des teneurs en terpènes qui serait probablement en relation avec l’accroissement
des épaisseurs de parenchyme palissadique et la forte densité de poils glanduleux. Pour
discriminer les traits adaptatifs de ceux qui ne le sont pas, une étude a été réalisée sur des
plantules originaires de 2 des stations étudiées. Nous avons montré que les plantules de la station
la plus aride (Béchar) avaient une activité photosynthétique nette et un rendement quantique
supérieurs aux plantules du milieu le moins aride (Médéa). L’analyse des clichés de microscopie
électronique a permis de dire que ces différences étaient dues à des limitations stomatiques,
confirmant ainsi le caractère adaptatif de ces traits photosynthétiques.
La deuxième partie de ce travail réalisée in situ a révélé une grande variabilité de la composition
terpénique chez 75 populations de lentisque algériennes. Trois chémotypes ont été identifiés en
fonction de l’altitude. Les teneurs les plus élevées ont été enregistrées chez les populations de
haute altitude ce qui conforte l’hypothèse du rôle de protection des terpènes contre les UV.
Dans la troisième partie, la plasticité de l’appareil photosynthétique du lentisque a été étudiée
durant les 4 saisons de l’année in situ, dans trois sites très contrastés en France; semi aride, aride
et salin. Les résultats obtenus ont révélé une photoinhibition chronique de l’appareil
photosynthétique en hiver accompagnée par des taux les plus faibles en chlorophylle,
essentiellement dans les sites salins. Elle serait due à l’inefficacité dans la conversion de l’énergie
lumineuse par les antennes de PSII. Au printemps, la valeur de l’efficacité quantique maximale
était plus élevée chez les arbres femelles et s’expliquerait par une forte allocation des ressources
carbonées destinées pour le développent de fruit durant cette saison. La protection de l’appareil
photosynthétique, contre une photoinhibition chronique estivale est justifiée par un taux élevé du
ratio caroténoïdes/chlorophylle. En Automne, il y a reprise de l’activité physiologique avec une
meilleure résilience enregistrée dans les sites arides. Pour mieux comprendre la physiologie du
lentisque en bord de mer, des plantules originaires de la station littorale (Montredon) ont été
étudiées en chambre de culture. Les résultats obtenus en microscopie confocale ont montré que
cette espèce séquestre le sodium dans les cellules épidermiques ainsi que dans les parois
cellulaires. Les effets néfastes de NaCl sur le rendement quantique et l’assimilation nette du CO2
au cours de la photosynthèse sont nettement améliorés en milieu calcaire
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
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
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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