1,720,982 research outputs found
Morphometric distinction between bilobate phytoliths from Panicum miliaceum and Setaria italica leaves
The development of identification criteria for crop plants based on phytoliths is of high relevance for archaeology, palaeoecology and plant systematics. While identification criteria are available for major food crops, these are mostly based on phytoliths from inflorescences, while other plant parts remain undetected. This paper focuses on bilobate phytoliths from leaves of Panicum miliaceum L. (common millet) and Setaria italica (L.) P. Beauv. (foxtail millet), two taxa that co-occur in regions of Asia and Europe since prehistory and regularly occur at archaeological sites in Eurasia. Leaves of the investigated taxa were systematically sampled to explore the variation of short cells and to collect 27 morphometric variables of bilobate phytoliths with newly developed open-source software. The data was analysed by discriminant analysis, analysis of variance and multiple comparison tests. The resulting morphometric data from five populations per species enables a distinction between the bilobate phytoliths of P. miliaceum and S. italica. Observed differences between populations within species affect only few parameters. This possibility to classify populations of bilobate phytoliths from P. miliaceum and S. italica leaves offers a new method for the detection and identification of these taxa in archaeology, amongst others.This study was partially supported by a Marie Curie Intra European Fellowship [PHYTORES, 273610, 2011–2013].Peer reviewe
Late Mesolithic and Early Neolithic human impact at Dutch wetland sites: the case study of Hardinxveld-Giessendam De Bruin
Evidence of human impact on the vegetation obtained from pollen diagrams at sites in the process of neolithisation is often difficult to detect. Apart from aspects like site function and occupation intensity, methodological aspects play a considerable role. In the Rhine-Meuse delta in the Netherlands, neolithisation is documented at the Final Mesolithic sites Hardinxveld-Giessendam Polderweg and Hardinxveld-Giessendam De Bruin and the local Early Neolithic sites of Brandwijk-Kerkhof and the Hazendonk, covering the period of 5500–2500 cal. B.C. The off-site core from Hardinxveld-Giessendam De Bruin supports earlier results that human influence on the vegetation at Hardinxveld is restricted and difficult to distinguish from natural vegetation disturbance. Human impact is more easily recognisable in the diagrams of Neolithic phases at Brandwijk-Kerkhof and the Hazendonk that show evidence of both domestic animals and cereals. Continuing Neolithisation and also research methodology, including the location of the pollen cores, may play a role in this. It is tested whether the use of a new pollen sum excluding extra-regional taxa increases the visibility of human impact
Going Beyond Counting First Authors in Author Co-citation Analysis
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
“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
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
Food from gardens in Northern Europe – Archaeobotanical and written records dated to the medieval period and early modern times.
What's in a hearth? Seeds and fruits from the Neolithic fishing and fowling camp at Bergschenhoek, The Netherlands, in a wider context
This paper presents new results from the Early Neolithic Dutch wetland site of Bergschenhoek (ca. 4200 cal b. c., Swifterbant Culture), which are compared with finds from similar features and sites. The data indicate the presence of predominantly eutrophic, nutrient-rich reed and forb vegetation and suggest the preparation of meals consisting of fish and fruits. The finds from the hearth, dominated by uncarbonised remains of wetland taxa, form a remarkable part of the find assemblage. Therefore, the discussion concerns assemblages, deposition processes and interpretations of uncarbonised and carbonised finds from hearths at comparable, contemporary sites. The wide variation of macroremains assemblages of hearths indicates that plant deposition in hearths is understood only partly and remains a topic for further research.Peer reviewe
Neolithisation at the site Brandwijk-Kerkhof, the Netherlands: natural vegetation, human impact and plant food subsistence
Branch age and diameter: useful criteria for recognising woodland management in the present and past?
When prehistoric archaeological sites yield non-carbonised wood, one of the ways to test for management practices consisting of pollarding and coppicing is analysis of branch diameter and age. However, the interpretation of such data is often based on assumptions. To test whether it is in fact possible to identify past woodland management on the basis of age/diameter analysis in archaeological wood assemblages, this paper presents models that predict the expected age and diameter distribution of branches from unmanaged and managed trees. The models have been tested using data on modern-day Alnus glutinosa, Fraxinus excelsior and species of the genus Salix. Branches of modern-day unmanaged and managed trees with a diameter up to approx. 2 cm (not an absolute limit) have a comparable age. Branches with a diameter of approx. 2–6 cm from unmanaged trees are older than similar branches from managed trees. The age distribution in the latter also ends abruptly. The age/diameter data from the modern-day trees indicate that the models can be used to discern management in the past, if branches up to approx. 2 cm in diameter are avoided and if, critically, taxon, sample size, growing conditions, natural disturbance/opportunistic wood collection and the possibility of diameter selection are taken into account. Archaeological datasets mainly from prehistoric sites are then reinterpreted by means of comparison with the models. Indications of management in prehistory as demonstrated by age/diameter are scarce but available. There is thus a clear need for further research in this field. Practical suggestions are provided for improving the quality of future research on woodland management practices by means of branch age/diameter analysisW. Out is a member of the Complexity and Socio-Ecological dynamics research cluster (cases-bcn.net) and is funded by a EU Marie Curie Intra-European fellowship (273610)Peer reviewe
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