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Master track of POLARSTERN cruise PS144 in 1 sec resolution (zipped, 243 MB)
No full textRaw data acquired by position sensors on board RV Polarstern during expedition PS144 was processed to receive a validated master track which can be used as reference of further expedition data. During PS144 two Trimble Marine R750 GPS receivers and the iXBlue HYDRINS hydrographic survey inertial navigation system were used as navigation sensors. Data were downloaded from DAVIS SHIP data base (https://dship.awi.de) with a resolution of 1 sec. Processed data are provided as a master track with 1 sec resolution derived from the position sensors' data selected by priority and a generalized track with a reduced set of the most significant positions of the master track
Radiumisotope als Tracer für den Elementkreislauf an ozeanischen Randgebieten
Get PDFTrace elements (TEs) play crucial roles in regulating ocean processes including marine biogeochemical cycles, and are therefore vital to support marine life. Understanding the biogeochemical cycling of TEs requires knowledge of their sources/ sinks and transport in the oceans. Radium isotopes are suitable tools to study inputs of elements from the continental margins, as they are produced by the decay of thorium isotopes in sediments, and are soluble in seawater. Therefore, in this Ph.D. thesis, I used Ra isotopes to determine boundary TE fluxes from two diverse environments that constrain the major TE sources, including shelf sediments in an Arctic shelf region and in an eastern boundary system off the western African coast, as well as rivers such as the River Congo.
First, the distributions of the dissolved and total dissolvable TEs (Cd, Fe, Ni, Cu, Zn, Pb, Mn, and Co) were investigated in the Chukchi Sea and 228Ra isotope was applied as tracer of benthic TE inputs. The results show that elevated benthic TE inputs on the Chukchi shelf provided suitable conditions for phytoplankton blooms. The 228Ra activities in spring appear to be 2-fold higher than in summer, which was a surprising observation and requires further investigation.
Next, 228Ra was used to investigate the influence of the Congo River on surface ocean TE concentrations in the South Atlantic Ocean. The results show that the Congo River plume constitutes a large and unexpected input of TEs (Fe, Mn, and Co) into the South Atlantic.
Finally, Ra isotopes were used to investigate a number of key ocean boundary processes in the Southeast Atlantic Ocean. Upwelling in the Benguela region is visible in the Ra distributions, and elevated Ra isotopes, Fe (II) and Si concentrations were observed in the Benguela oxygen minimum zone, possibly due to inputs from the reducing shelf sediments, or submarine groundwater discharge along the Namibian shelf.Spurenelemente spielen eine zentrale Rolle in der Regulation ozeanischer Prozesse einschließlich des marinen biogeochemischen Kreislaufs und sind dadurch eine zentrale Voraussetzung für das Leben im Meer. Das Verständnis der biogeochemischen Kreisläufe der Spurenelemente basiert auf dem Wissen um deren Quellen, Senken und Transportwege innerhalb des Ozeans. Die Radiumisotope, welche als Zerfallsprodukt von Thorium in Sedimenten entstehen, sind wasserlöslich und haben sich als nützliche Werkzeuge herausgestellt, die den Input von solchen Elementen aus den kontinentalen Hängen nachvollziehen lassen. Diese verwende ich in der vorliegenden Dissertation, um die bedeutendsten Spurenelementquellen zu beleuchten, die den Austausch zwischen Schelfsedimenten und dem angrenzenden Ozean vornehmen. Dies geschieht anhand zweier kontrastierender Umgebungen, dem arktischen Schelf und des östlichen „Grenzsystems“ vor der Küste Westafrikas, das auch Flusseinträge wie zum Beispiel aus dem Kongo beinhaltet.
Zunächst wurde die Verteilung der gelösten und säurelöslichen Spurenelemente (Cd, Fe, Ni, Cu, Zn, Pb, Mn und Co) in der Tschuktschensee untersucht. Als Tracer zur Bestimmung benthischen Eintrags wurde dort 228Ra verwendet.
Des Weiteren wurde 228Ra verwendet, um den Einfluss des Kongo, auf die im oberen Ozean befindlichen Spurenelemente im Südatlantik zu untersuchen. Die Ergebnisse zeigen, dass die Flusswasserfahne des Kongo einen unerwartet großen Eintrag bioessentieller Spurenelemente in den Südatlantik ausmacht.
Mit Hilfe der Radiumisotope wurden abschließend eine Reihe von Schlüsselprozessen im Grenzflächenaustausch des Südost-Atlantiks untersucht. Der Auftrieb der Benguela-Region ist ebenfalls in der Radiumverteilung ersichtlich. Gleichzeitig weisen erhöhte Konzentrationen der Radiumisotope, Fe (II) und Si in der Benguela-Sauerstoffminimumzone auf Zufuhr aus reduzierenden Schelfsedimenten oder aus unterseeischem Grundwasseraustritt entlang des Namibianischen Schelfs hin
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
Master tracks in different resolutions of POLARSTERN cruise PS144, Tromsø - Bremerhaven, 2024-08-09 - 2024-10-13
No full textRaw data acquired by position sensors on board RV Polarstern during expedition PS144 was processed to receive a validated master track which can be used as reference of further expedition data. During PS144 two Trimble Marine R750 GPS receivers and the iXBlue HYDRINS hydrographic survey inertial navigation system were used as navigation sensors. Data were downloaded from DAVIS SHIP data base (https://dship.awi.de) with a resolution of 1 sec. Processed data are provided as a master track with 1 sec resolution derived from the position sensors' data selected by priority and a generalized track with a reduced set of the most significant positions of the master track
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
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