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Abstract

The present study is an attempt to utilise the uranium-thorium dates ofspeleothems as a source ofpalaeoclimatic data. The clue is that the changing climate influenced intensity of speleothem deposition, which is reflected in clustering of U-Series dates of speleothems in certain time intervals. This work discusses and improves various methods of combined presentation of dates, with a special attention to the presentation in form of growth frequency ('pdf) curves. Using the 'bootstrap' method the confidence intervals of the 'pdf' curves could be determined. Also the algorithm, originally developed to determine parameters of arbitrarily chosen maxima in the curve, has been modified. Due to that an assessment of number of maxima has been possible. This method enables objective distinction of phases of speleothem growth, which cannot be done 'by eye' when the 'pdf' curve is smooth. The statistical tests show that the reliable 'pdf' curve should contain more than 150 dates. Basing on 308 U-series dates of cave speleothems from southern Poland and other regions of central Europe, the growth frequency curves for the Carpathians and Uplands have been constructed. Comparison of phases of speleothem growth, distinguished by various authors for several regions of Europe, indicates that the climatic changes were synchronous over the whole region. However, different shapes of the 'pdf' curves reflect increasing continuity ofspeleothem growth in the N-S transect southwards. This may be connected with the N-S climatic gradient in Europe. Using the 'pdf' curves from caves of Tatra and Low Tatra Mountains the most probable timing of development phases of mountain glaciers has been delimited.
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Authors and Affiliations

Helena Hercman
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Abstract

The paper examines the special historiographic evidence: the lost last book by the well-known Polish historian and methodologist Professor Jerzy Topolski entitled “Methodology of History at the Beginning of the 21st Century”. Only its working outline in the form of an extensive table of contents has survived, but this does not prevent the author from making interesting hypotheses as to its meaning.

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Authors and Affiliations

Jan Pomorski
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Abstract

In this text, we analyze the limitations of using academic age as a proxy for biological age in the whole national science system, for which we consider both biological age and academic age of all researchers from all Polish universities, holding at least a PhD degree and participating in global academic science through international publications (N = 20 569). An approximation of a researcher's functioning in global science is having at least one publication indexed in the Scopus database in the analyzed decade 2009–2018. Thus, using the example of comprehensive data from the entire national system of science, we estimate the extent of limitations of using academic age as a proxy for biological age depending on selected independent variables and analyze both the practical and methodological implications of using academic age in academic career research, which is one of the most important components of quantitative studies of science.
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Authors and Affiliations

Marek Kwiek
ORCID: ORCID
Wojciech Roszka
ORCID: ORCID

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