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    Ophiolitic sequences from the central sector of the Catena Costiera (Calabria): stratigraphy, petrology and structural analyses

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    Mesozoic ophiolites crop out in the Catena Costiera (Northern Calabrian Arc). The Northern Calabrian Arc is characterized by the superposition of three structural elements (OGNIBEN, 1973): the uppermost Hercynian continental section intruded by late- Variscan granitoids (Calabrian Nappe), the intermediate ophiolitic Nappe and the lowermost Mesozoic passive margin carbonate sequences (Apenninic Units). The studied area is located in the central Catena Costiera (fig. 1) where the ophiolitic sequences are characterized by both aphyric and porphyritic metabasalts with a T-MORB affinity (LIBERI et alii, 2006). They represent the basement of a peliticarenaceous metasedimentary sequence, previously interpreted as a pre-Mesozoic continental basement (Bagni Unit of AMODIO MORELLI et alii, 1976). In the metasedimentary cover, a remarkable increase in the carbonatic supply is noticed moving from south to north of the study area. According to this evidence two stratigraphic sequences have been defined for the southernmost Cozzo Cervello area and the northernmost San Martino di Finita area. The Cozzo Cervello area ophiolitic sequence is characterized by: metabasites, thin levels of volcanoclastic metasediments, rare metacarbonates, metapelites and metarenites. The San Martino di Finita area ophiolitic sequence is instead characterized by: metabasites, volcanoclastic metasediments and calcschists. The studied rocks underwent a polyphase deformation history and the meso- and microstructural analyses allowed distinguishing three main (D1-D3) deformation phases: – D1, this phase is characterized by a S1 foliation locally developed and preserved as microlithons inside the S2 main foliation; – D2, a N-S trending isoclinal folding event (F2; fig. 2 a,b) is responsible for the formation of the S2 foliation (fig. 2 d), that represent the main surface recognizable in the field; – D3, this phase is characterized by asymmetric folds (F3) developed at different scales and showing a WNW-ESE trending axes. An incipient foliation (S3) is locally developed in the phyllosilicate-rich levels (fig. 2 c,d). *Dipartimento di Scienze della Terra, Università della Calabria. ([email protected]) **Dipartimento di Scienze della Terra, Università di Pisa The petrographic analysis allows to define the mineralogical assemblage of the different lithotypes and to determine the relationships between deformation and blastesis. The metabasites are characterized by the mineralogical assemblage: Epidote + Na-amphibole + Lawsonite + Phengite + Chlorite + Albite Calcite Quartz + Magnetite. Metapelites and metarenites are characterized by: Epidote + Phengite + Stilpnomelane + Na-Amphibole + Pumpellyite + Chlorite + Albite + Quartz + Magnetite. The calcschist are constituted by: Calcite + Phengite + Chlorite + Albite + Quartz + Magnetite. The described mineralogical assemblages suggest that the studied rocks underwent P-T conditions typical of the blueschist facies as suggested by the blastesis of Na-amphiboles, lawsonite, stilpnomelane and phengite along the S2 foliation. The blastesis of white mica can be observed along the S3 foliation also. The following metamorphic retrogression developed within the prehnitepumpellyite facies and is characterized by a static recrystalization. Fig. 1 – Tectonic sketch map of central sector of the Catena Costiera, after LIBERI et alii (2006). 64 OPHIOLITIC SEQUENCES FROM THE CATENA COSTIERA 65 Fig. 2 – a) isoclinal folds (F2) in the metapelites of Cozzo Cervello area; b) isoclinal folds (F2) in the calcschists of San Martino di Finita area; c) crenulation F3 in the metabasites; d) microscopic view of the main foliation S2 deformed by the later D3 phase in the metapelites. The white line indicates white mica flakes along S3. The field study and the tectonometamorphic evolution reconstructed for the ophiolitic sequences cropping out in the central sector of the Catena Costiera of Calabria show that a subduction and exhumation history inside an accretionary wedge can be proposed. In particular, the characterization and the definition of the complex relationships existing within the ophiolitic metasedimentary cover allow us to propose: 1. the source area was composite, with both carbonatic and siliciclastic contributions; 2. the presence of terrigenous deposit, even in the lowermost part of the sedimentary sequence, seem to indicate that this part of oceanic crust was located close to the continental margin; 3. the San Martino di Finita type sedimentary cover can be correlated with that of the Malvito ophiolitic unit (sensu AMODIO MORELLI et alii, 1976), cropping out in the northernmost sector of the Catena Costiera; 4. the subdivision between the Bagni and Gimigliano-Monte Reventino Units, as proposed by DIETRICH & SCANDONE (1972) and AMODIO MORELLI et alii (1976) for the study area, is not supported by the data collected in this work. REFERENCES AMODIO MORELLI L., BONARDI G., COLONNA V., DIETRICH D., GIUNTA G., IPPOLITO F., LIGUORI V., LORENZONI S., PAGLIONICO A., PERRONE V., PICCARRETA G., RUSSO M., SCANDONE P., ZANETTIN-LORENZONI E. & ZUPPETTA A. (1976) - L’arco Calabro-peloritano nell’orogene appenninicomagrebide. Mem. Soc. Geol. It, 17, 1–60. DIETRICH D. & SCANDONE P. (1972) - The position of the basic and ultrabasic rocks in the tectonic units of the southern Apennines. Atti Acc. Pont., 21, 61–75. LIBERI F., MORTEN L. & PILUSO E. (2006) - Geodynamic significance of the ophiolites within the Calabrian Arc. Island Arc, 15, 26–43. OGNIBEN L. (1973) - Schema geologico della Calabria in base ai dati odierni. Geologia Romana, 12, 243

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The 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

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    “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

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    We 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

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    We 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

    Author Index

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    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    We 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 Under Sail The Imagination of Jack London, 1893-1902

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    In 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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