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The sedimentary history of loess : sources, deposition, and reworking of aeolian sediments as indicators for palaeoenvironmental changes in the Danube Basin
No full textLoess is a windblown dust deposit, which covers approximately 10% of the Earth’s surface. Especially the Eurasian mid-latitudes are mantled by a belt of loess deposits spanning from southern England towards the steppes of Central Asia. Despite its terminal atmospheric deposition, the formation of loess is a complex chain including several geomorphological and sedimentological processes. Aeolian processes cannot solely produce dust particles in sufficient amounts. During the Pleistocene, grinding of Alpine glaciers and continental ice sheets – as well as physical weathering phenomena such as frost shattering in periglacially influenced high-latitudes and -altitudes were among the essential formation processes of silt production. Rivers are another important factor, since they erode and transport unconsolidated sediments and increase dust formation due to abrasion during riverine transport. After the deposition of fluvial and alluvial de-posits, fine particles, mostly in the silt fraction, can be deflated and transported by wind. Topographic barriers or biotic components, such as vegetation or biocrusts, trap the particles. The aeolian dust undergoes post-depositional alterations, so-called loessification processes, which help to preserve the deposit. Despite these processes, loess is prone to erosion, especially to reworking by water. In Europe, the distribution of loess and other aeolian sediments is strongly related to (palaeo-)geographic conditions and the (palaeo-)climate influencing the process chain of loess formation. The catchment of the Danube River, especially in its middle and lower course, is one of the most important loess regions in Europe since loess covers vast areas of the basin and the records reach back to the Early Pleistocene. Due to thicknesses, which in some instances exceed 50 m, the loess deposits of the Danube Basin are a crucial archive for palaeoclimatic and palaeoenvironmental changes in Central and Southeast Europe. The interplay of the Atlantic, Mediterranean, and continental climate regimes influences this region. The present dissertation casts light on the sedimentary history of loess deposits of the Danube Basin to highlight its applicability as an archive of palaeoenvironmental changes. The sedimentary history includes the process chain of loess formation and possible post-depositional alteration such as reworking by water. Especially dust deflation, transport, and deposition via sedimentary pathways, the vegetation patterns trapping aeolian mineral dust and related ecosystem qualities, and the post-depositional reworking of aeolian sediments due to landscape instability are investigated to understand palaeoclimatic and palaeoenvironmental changes. This dissertation examines the physical and chemical properties of seven loess-palaeosol sequences and one archaeological excavation from various geomorphological settings to unravel regional environmental patterns for the Middle and Lower Danube Basin. To reconstruct the deflation and aeolian transport of dust, sedimentary pathways for Pleniglacial loess deposits from the Lower Danube Basin are reconstructed based on geochemical compositions of five loess-palaeosol sequences, distributed along a cross-section from the plateau of the Dobrogea in the south towards the northern Wallachian Plain. The comparison with loess depos-its of reference regions revealed that the alluvial deposits of the Danube and its tributaries draining the Carpathians and Balkan Mountains are the primary source for the loess deposits of the southern Lower Danube Basin indicating westerly palaeowind directions. Northwards, a consider-able amount of dust derived from the rivers draining the flysch zones of the Eastern Carpathians, such as Siret, Prut, or Dniester, pointing to stronger north-westerly winds. Based on stable carbon and nitrogen isotope analyses of two loess-palaeosol sequences from the Middle Danube Basin, Irig and Semlac, the vegetation of the basin during the Middle to Late Pleistocene was dominated by C3 plants, most likely grasses, which acted as an efficient dust trap. The isotopic composition of the two sequences also reveals a palaeoclimatic gradient in the basin, as the South of the basin seems to have been experiencing drier conditions compared to the north. The geochemical evidence highlights the importance of aridity as a palaeoecological factor that influenced vegetation patterns and ecosystem qualities during interglacial and interstadial periods. The Upper Palaeolithic findspot of Temereşti Dealu Vinii was investigated to reconstruct site-formation processes of a reworked archaeological open-air site. Temereşti shows no evident stratification, and lithic artefacts from the Aurignacian and (Epi-)Gravettian cultural units permeate the sequence with (typological) age inversions and no horizontal concentrations. The primarily aeolian sediments were (sub-)continuously translocated by fluvial processes. Based on geomorphological evidence and the lack of wear on the found artefacts, the range of transport is constrained to the width of the river terrace on which the site is located. Reworking took place during known phases of landscape instability during the Holocene in the area. This dissertation illuminates the steps of the sedimentary history of loess as palaeoenvironmental indicators for the Pleistocene in the Danube Basin. It highlights the importance of multi-proxy approaches by the application of three different courses on loess deposits from different milieus. These approaches are combined to unravel regional palaeoenvironmental patterns of Southeast Europe in the context of the dispersal of anatomically modern humans into the subcontinent during the Pleniglacial
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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