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271.
Isabell Schmidt Johanna Hilpert Inga Kretschmer Robin Peters Manuel Broich Sara Schiesberg Oliver Vogels Karl Peter Wendt Andreas Zimmermann Andreas Maier 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2021,376(1816)
In many theories on the social and cultural evolution of human societies, the number and density of people living together in a given time and region is a crucial factor. Because direct data on past demographic developments are lacking, and reliability and validity of demographic proxies require careful evaluation, the topic has been approached from several different directions. This paper provides an introduction to a geostatistical approach for estimating prehistoric population size and density, the so-called Cologne Protocol and discusses underlying theoretical assumptions and upscaling transfer-functions between different spatial scale levels. We describe and compare the specifics for farming and for foraging societies and, using examples, discuss a diachronic series of estimates, covering the population dynamics of roughly 40 kyr of European prehistory. Ethnohistoric accounts, results from other approaches—including absolute (ethno-environmental models) and relative estimates (site-numbers, dates as data, etc.) allow a first positioning of the estimates within this field of research. Future enhancements, applications and testing of the Cologne Protocol are outlined and positioned within the general theoretical and methodological avenues of palaeodemographic research. In addition, we provide manuals for modelling Core Areas in MapInfo, ArcGIS, QGIS/Saga and R.This article is part of the theme issue ‘Cross-disciplinary approaches to prehistoric demography’. 相似文献
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Maurice Vogels Rita Zoeckler Donald M. Stasiw Lawrence C. Cerny 《Journal of biological physics》1975,3(4):183-192
The purpose of this publication as a pedagogical contribution is to report what is perhaps the first mathematical treatment of population statistics. This translation of an important paper by P. F. Verhulst was written at a time when the ideas of Malthus were extremely popular. It is believed that Verhulst's contribution was the first explanation of what is currently considered the logistic equation or the S-shaped curve. 相似文献
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Gert-Jan W. M. van Alebeek Gaalda Tafazzul Michael J. J. Kreuwels Jan T. Keltjens Godfried D. Vogels 《Archives of microbiology》1994,162(3):193-198
The levels of cyclic 2,3-diphosphoglycerate (cDPG) in methanogenic bacteria are governed by the antagonistic activities of cDPG synthetase and cDPG hydrolase. In this paper we focus on the synthetase from Methanobacterium thermoautotrophicum. The cytoplasmic 150 kDa enzyme catalyzed cDPG synthesis from 2,3-diphosphoglycerate (apparent Km=21 mM), Mg2+ (Km=3.1 mM) and ATP (Km=1–2 mM). In batch-fed cultures, the enzyme was constitutively present (6–6.5 nmol per min per mg protein) during the different growth phases. In continuous cultures, activity decreased in response to phosphate limitation. The synthetase reaction proceeded with maximal rate at pH 6 and at 65° C and was specifically dependent on high (>0.3M) K+ concentrations. The reaction conditions remarkably contrasted to those of cDPG degradation catalyzed by the previously described membrane-bound cDPG hydrolase.Abbreviations
cDPG
Cyclic 2,3-diphosphoglycerate
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2,3-DPG
2,3-Diphosphoglycerate
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2-PG
2-Phosphoglycerate
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3-PG
3-Phosphoglycerate 相似文献
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Improved method for simultaneous determination of alcohols, volatile fatty acids, lactic acid or 2,3-butanediol in biological samples 总被引:1,自引:0,他引:1
M.J. Teunissen S.A.E. Marras H.J.M. Op den Camp G.D. Vogels 《Journal of microbiological methods》1989,10(4):247-254
A rapid and sample procedure was developed to determine, by gas-liquid chromatography, the concentrations of C2---C4 alcohols, C2---C6 volatile fatty acids (VFA) and lactic acid or 2,3-butanediol in fermentation liquids. both lactic acid and 2,3-butanediol are oxidized to acetaldehyde by periodic acid and acetaldehyde was eluted before ethanol. A complete separation of the alcohols and acids was performed in <15 min on a column packed with 80/100 Chromosorb WAW, having GP 10% SP-1200/1% H3PO4 as the liquid phase. The method was suitable for the analysis of rumen fluid and fermentation products from microbial cultures. The detection limits for all compounds were <0.13 nmol · injection−1. 相似文献
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