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Author Correction: Palaeogenomics of Upper Palaeolithic to Neolithic European hunter-gatherers
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Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
A coordinate independent treatment of the Standard Model Lagrangian
No full textDas Ziel dieser Masterarbeit ist eine Ausarbeitung des mathematischen Rahmens für die Standard Modell Lagrange-Dichte mithilfe von Prinzipalbündeln, Prinzipalbündelzusammenhängen und assoziierten Vektorbündeln. Der entwickelte Formalismus erlaubt es, die Langrangedichte für klassische Felder über gekrümmten Raumzeiten ausgestattet mit einer Spinstruktur zu formulieren. Angewandt auf den Minkowski-Raum ergibt er die übliche Standard Modell Lagrange-Funktion. Ein großer Teil der Arbeit beschäftigt sich mit der Konstruktion von kinetischen Termen für fermionische Felder und wie man diese mit Spinor-Bündel modelliert. Letztere sind irreduzible komplexe Clifford-Bündel-Moduln und auf ihnen wird ein Dirac-Operator konstruiert. Zu diesem Zweck werden Spin invariante Sesquilinearformen auf einem komplexen Spinorraum der Dimension r + s = 2k untersucht.The aim of this master thesis is to discuss the mathematical setting for the Standard Model Lagrangian within the framework of principal bundles, principal connections and associated bundles. The formalism developed here allows to state the Lagrangian density for classical fields over a curved spacetime equipped with a spin structure. Applied to standard Minkowski space it yields the usual Standard Model Lagrangian. The main part of this thesis focuses on the construction of kinetic terms for fermionic fields and how to
model them with spinor bundles. The latter are irreducible complex Clifford bundle modules. We construct a Dirac operator on them and discuss the existence of invariant forms. Therefore we study Spin invariant sesquilinear forms on a complex spinor space of dimension r + s = 2k
Palaeogenomics of Upper Palaeolithic to Neolithic European hunter-gatherers
No full textAbstract Modern humans have populated Europe for more than 45,000 years 1,2 . Our knowledge of the genetic relatedness and structure of ancient hunter-gatherers is however limited, owing to the scarceness and poor molecular preservation of human remains from that period 3 . Here we analyse 356 ancient hunter-gatherer genomes, including new genomic data for 116 individuals from 14 countries in western and central Eurasia, spanning between 35,000 and 5,000 years ago. We identify a genetic ancestry profile in individuals associated with Upper Palaeolithic Gravettian assemblages from western Europe that is distinct from contemporaneous groups related to this archaeological culture in central and southern Europe 4 , but resembles that of preceding individuals associated with the Aurignacian culture. This ancestry profile survived during the Last Glacial Maximum (25,000 to 19,000 years ago) in human populations from southwestern Europe associated with the Solutrean culture, and with the following Magdalenian culture that re-expanded northeastward after the Last Glacial Maximum. Conversely, we reveal a genetic turnover in southern Europe suggesting a local replacement of human groups around the time of the Last Glacial Maximum, accompanied by a north-to-south dispersal of populations associated with the Epigravettian culture. From at least 14,000 years ago, an ancestry related to this culture spread from the south across the rest of Europe, largely replacing the Magdalenian-associated gene pool. After a period of limited admixture that spanned the beginning of the Mesolithic, we find genetic interactions between western and eastern European hunter-gatherers, who were also characterized by marked differences in phenotypically relevant variants
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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
Isotopic and DNA analyses reveal multiscale PPNB mobility and migration across Southeastern Anatolia and the Southern Levant
No full textGrowing reliance on animal and plant domestication in the Near East and beyond during the Pre-Pottery Neolithic B (PPNB) (the ninth to eighth millennium BC) has often been associated with a “revolutionary” social transformation from mobility toward more sedentary lifestyles. We are able to yield nuanced insights into the process of the Neolithization in the Near East based on a bioarchaeological approach integrating isotopic and archaeogenetic analyses on the bone remains recovered from Nevalı Çori, a site occupied from the early PPNB in Turkey where some of the earliest evidence of animal and plant domestication emerged, and from Ba'ja, a typical late PPNB site in Jordan. In addition, we present the archaeological sequence of Nevalı Çori together with newly generated radiocarbon dates. Our results are based on strontium ( 87 Sr/ 86 Sr), carbon, and oxygen (δ 18 O and δ 13 C carb ) isotopic analyses conducted on 28 human and 29 animal individuals from the site of Nevalı Çori. 87 Sr/ 86 Sr results indicate mobility and connection with the contemporaneous surrounding sites during the earlier PPNB prior to an apparent decline in this mobility at a time of growing reliance on domesticates. Genome-wide data from six human individuals from Nevalı Çori and Ba'ja demonstrate a diverse gene pool at Nevalı Çori that supports connectedness within the Fertile Crescent during the earlier phases of Neolithization and evidence of consanguineous union in the PPNB Ba'ja and the Iron Age Nevalı Çori.Max Planck Harvard Research Center for the Archaeoscience of the Ancient MediterraneanChina Scholarship Council 501100004543Max Planck Societ
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