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(Table 1) Age control points of ODP Site 160-968
No full textThe astronomical timescale of the Eastern Mediterranean Plio-Pleistocene builds on tuning of sapropel layers to Northern Hemisphere summer insolation maxima. A 3000-year precession lag has become instrumental in the tuning procedure as radiocarbon dating revealed that the midpoint of the youngest sapropel, S1, in the early Holocene occurred approximately 3000 years after the insolation maximum. The origin of the time lag remains elusive, however, because sapropels are generally linked to maximum African monsoon intensities and transient climate modeling results indicate an in-phase behavior of the African monsoon relative to precession forcing. Here we present new high-resolution records of bulk sediment geochemistry and benthic foraminiferal oxygen isotopes from ODP Site 968 in the Eastern Mediterranean. We show that the 3000-year precession time lag of the sapropel midpoints is consistent with (1) the global marine isotope chronology, (2) maximum (monsoonal) precipitation conditions in the Mediterranean region and China derived from radiometrically dated speleothem records, and (3) maximum atmospheric methane concentrations in Antarctica ice cores. We show that the time lag relates to the occurrence of precession-paced North Atlantic cold events, which systematically delayed the onset of strong boreal summer monsoon intensity. Our findings may also explain a non-stationary behavior of the African monsoon over the past 3 million years due to more frequent and intensive cold events in the Late Pleistocene
High-resolution elemental concentration measurements of ODP Sites 160-967 and 160-968
No full textWe completed and merged an existing high-resolution X-Ray Fluorescence (XRF) data set derived from Ocean Drilling Program (ODP) site 968 with new data from adjacent ODP site 967. An astronomical age model spanning the last 1.05 Myr was constructed for the spliced record using the highly linear relation between the elemental ratio of titanium and aluminum in the sediment (Ti/Al) and insolation. This rendered detailed ages for sapropel deposition in the Eastern Mediterranean. Our results imply major revisions of previous sapropel age models below MIS 11, with changes of up to two precession cycles in the interval ~450-850 ka of the ODP 967 sapropel chronology. Based on the Ti/Al age model, we find that color reflectance - used as an indicator for sapropels in this interval of ODP site 967 and 968 - is highly incongruent with the Ti/Al proxy as well as insolation forcing during periods of minima in the 405 kyr eccentricity cycle. Our findings indicate that the use of color reflectance as a proxy for so-called ghost sapropels in these intervals is not reliable. Lastly, we demonstrate the presence of a strong obliquity signal in the Ti/Al record that lags obliquity forcing by 4±0.7 kyr). This time lag is only marginally longer than the adopted 2.7±1.1 kyr for the dominantly precession-tuned age model, and is hence much shorter than the generally accepted ice sheet response time to insolation forcing. This suggests that the obliquity-bound changes in Ti/Al are not glacial controlled and most likely reflect changes in low-latitude climate oscillations, such as the monsoon
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
968. Chronicon regum Francorum
No full text968. Chronicon regum Francorum. In: Molinier Auguste. Les Sources de l'histoire de France - Des origines aux guerres d'Italie (1494). II. Époque féodale, les Capétiens jusqu'en 1180. Paris : A. Picard et fils, 1902. p. 10
968. Chronicon regum Francorum
No full text968. Chronicon regum Francorum. In: Molinier Auguste. Les Sources de l'histoire de France - Des origines aux guerres d'Italie (1494). II. Époque féodale, les Capétiens jusqu'en 1180. Paris : A. Picard et fils, 1902. p. 10
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
Suddarth, James Damon (FA 968)
Get PDFFinding aid only for Folklife Archives Project 968. Project titled: “Folk Songs.” Includes survey sheets with brief descriptions of folk songs collected in Warren County, Kentucky and Tennessee. Sheets include a title, lyrics, and informant’s name
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