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Quicklime samples were collected from six vertical layers (L1–L6) of a feedstock calcined in a traditional single-batch wood-fired kiln and assessed. Three samples were well-burned and three under-burned. The quicklime was slaked in an excess of water and the presence of unburned particles was investigated after settling it into putty. The putty was assessed as bulk and also at three depth levels. Thermal analysis determined the CO2 residua in the quicklime samples. Cathodoluminescence detected individual unburned particles and image analysis was used for their quantification. Settling of the putties led to a considerable reduction of geogenic particles in the layers above the bottom. This was also confirmed by the stable isotope analysis. In the case of the putties made from well-burned quicklime, the δ13C values of samples L4 and L5 ranged from –25.5‰ to –20.5‰ VPDB, and the δ18O values ranged from –17.5‰ to –16.5‰ VPDB. The fractionation was likely affected by the division according to the particle size during the sedimentation. The results of the 14C analysis correlate with the quantified percentage of cathodoluminescent particles. [ABSTRACT FROM AUTHOR]

Nitra-Lupka is an important site from the Great Moravian period in Slovakia. A fortified hillfort which was supposed to be from this period, a battery of pottery kilns, and an Early Medieval cemetery were found on the site and researched during 1959–1975. Further, a few small-range excavations took place on the site at the beginning of the 21st century. At the same time, the dating of the hillfort to the Early Medieval period has begun to be questioned. There was also a problem with the localization of settlement that would belong to the battery of pottery kilns. The settlement was discovered recently in 2021 during development-led excavations at Nitra-Šindolka. It was found at the place of the construction of the ecoduct. Two ovens and four other features with numerous ceramics and other findings were discovered. Some of the bones (phalanges of cattle and goat/sheep) were dated by radiocarbon dating being the first 14C data obtained from this site and therefore of high importance for its precise dating. [ABSTRACT FROM AUTHOR]

Dating organic inclusions in mortars such as charcoals is a useful alternative or complementary method to dating mortars themselves, helping to estimate the building age. To assess the limitations of this dating approach, organic inclusions were searched for in surface mortar layers of six early to late medieval buildings in the Czech Republic with relatively well-known age. Altogether, 123 samples were found. About 80% were successfully radiocarbon (14C) dated. However, only 66% originated from wood relatively young when used in lime burning. To judge which samples are relevant to the actual building date, sufficient statistics is crucial. We recommend dating at least 5–10 samples, i.e., collecting 6–12 samples, for a site with uncomplicated building history, or per building phase. Otherwise, unrealistically old or young dates might be obtained. With the recommended statistics, inclusion-based dating provides building ages with uncertainty of 50–100 years. [ABSTRACT FROM AUTHOR]

The fifth season of excavations of Oponice Castle in 2020 was located in the lower castle's courtyard. The research led to discovery of an original clay floor being heavily burned with charred plank and a rectangular stone-brick construction. The construction has collapsed upper part with a fallen low brick arch. The whole area was covered with numerous stove tiles and one clay mold for the production of stove tiles. The construction was identified as a pottery kiln dated to the second half of the 16th until the first half of the 17th century AD by the findings from excavated layer identified to the kiln destruction. Also, written sources mention a large fire in 1645 which destroyed the castle. The aim of this article is to use different methods of dating and refine the chronology of the context through microarchaeology and Bayesian modeling. For these purposes different types of samples were collected. The sampling focused on site formation process determination of pottery kiln use and the way of its destruction. Applying Bayesian analysis improved overall dating, through modeled time interval of the three individual sequences and helped recreated historical events during the period, when the calibration curve fluctuates. [ABSTRACT FROM AUTHOR]

An archaeological excavation conducted on U Kasáren St. in the Prague Castle area (Czech Republic) in 2020 revealed the remains of a medieval settlement consisting of houses of different constructions (pit dwelling, masonry construction), pyrotechnical (possibly metallurgical) features and unspecified pits. The excavation also revealed evidence of fire events and traces of viniculture on the outskirts of the Prague Castle area. Archaeological data allowed only a rough dating of the investigated settlement in the 10th–13th centuries. This paper presents the results of the radiocarbon dating of various materials (animal bones, archaeobotanical samples) from the settlement features and the contribution of the results to the clarification of the chronology of the site. [ABSTRACT FROM AUTHOR]

Compromised detection of short DNA fragments can result in underestimation of radiation-induced clustered DNA damage. The fragments can be detected with atomic force microscopy (AFM), followed by image analysis to compute the length of plasmid molecules. Plasmid molecules imaged with AFM are represented by open or closed curves, possibly with crossings. For the analysis of such objects, a dedicated algorithm was developed, and its usability was demonstrated on the AFM images of plasmid pBR322 irradiated with 60Co gamma rays. The analysis of the set of the acquired AFM images revealed the presence of DNA fragments with lengths shorter than 300 base pairs that would have been neglected by a conventional detection method. [ABSTRACT FROM AUTHOR]

A compromised detection of radiation-induced plasmid DNA fragments results in underestimation of calculated damage yields. Electrophoretic methods are easy and cheap, but they can only detect a part of the fragments, neglecting the shortest ones. These can be detected with atomic force microscopy, but at the expense of time and price. Both methods were used to investigate their capabilities to detect the DNA fragments induced by high-energetic heavy ions. The results were taken into account in calculations of radiation-induced yields of single and double strand breaks. It was estimated that the double strand break yield is twice as high when the fragments are at least partially detected with the agarose electrophoresis, compared to when they were completely omitted. Further increase by 13% was observed when the measured fragments were corrected for the fraction of the shortest fragments up to 300 base pairs, as detected with the atomic force microscopy. The effect of fragment detection on the single strand break yield was diminished., (© The Author(s) 2018. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)