Enamel from 6 different positions in a well preserved elephant tooth from the Kärlich-Seeufer site in Germany has been irradiated up to 32 kGy. The X-band (v = 9.5 GHz) ESR spectra of two subsamples have been decomposed into three real components with Maximum Likelihood Common Factor Analysis (MLCFA). One of these components due to orthorhombic CO2- radicals is predominant. Dose response curves for the contributions of these MLCFA components and for different heights in the ESR spectra have been obtained and fitted with different models. Depending on the model, the equivalent dose for the preferably used height at g = 1.9973, due to CO2-, ranges from 70 to 130 Gy. Due to a very low uranium and thorium content in both enamel and dentine (< or = approximately 10 ppb) and to an important external y-attenuation, the ages fluctuate between 300 and 575 ka.
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http://dx.doi.org/10.1016/s0969-8043(00)00091-9 | DOI Listing |
Materials (Basel)
July 2024
Institute of Materials Science and Engineering, Technical University, 90-924 Lodz, Poland.
The aim of the study was to compare the hardness, coefficient of friction, and wear experienced by four different ceramic samples: 3Y-TZP zirconium oxide ceramics-Zi-Ceramill Zi (Amman Girrbach), 5Y-PSZ transparent zirconium oxide ceramics-Zol-Ceramill Zolid (Amman Girrbach), Sak-feldspathic ceramics-Sakura Interaction (Elephant), and Glaze (Amman Girrbach). The Vickers hardness of the samples was measured. Friction tests ball-on-disc were performed between the discs of four ceramics and a zirconia ceramic ball, then a premolar tooth as a counter-sample.
View Article and Find Full Text PDFMarine predators are vital to the healthy functioning of coastal ecosystems, but to understand their roles, it is necessary to elucidate their movement ecology, particularly in relation to one another. A decade's worth of acoustic telemetry data (2011-2020) from Algoa Bay, South Africa, was investigated to determine how two mesopredatory species (teleosts: dusky kob Argyrosomus japonicus, n = 11, and leervis Lichia amia, n = 16) and two top predatory species (sharks: ragged-tooth sharks Carcharias taurus, n = 45, and white sharks Carcharodon carcharias, n = 31) used and shared this bay ecosystem. Multi-annual seasonal fidelity to the bay was exhibited by all species, but differences in residency were observed among species.
View Article and Find Full Text PDFSci Rep
January 2024
Paleoanthropology, Institute for Archaeological Sciences, Department of Geosciences, Eberhard Karls University of Tübingen, Tübingen, Germany.
The Balkans are considered a major glacial refugium where flora and fauna survived glacial periods and repopulated the rest of Europe during interglacials. While it is also thought to have harboured Pleistocene human populations, evidence linking human activity, paleoenvironmental indicators and a secure temporal placement to glacial periods is scant. Here, we present the first intra-tooth multi-isotope analysis for the European straight-tusked elephant Palaeoloxodon antiquus, on an adult male individual excavated in association with lithic artefacts at the MIS 12 site Marathousa 1 (Megalopolis basin, Greece).
View Article and Find Full Text PDFProc Natl Acad Sci U S A
December 2023
Faculty of Archaeology, Leiden University, 2300 RA Leiden, The Netherlands.
Neanderthals hunted and butchered straight-tusked elephants, the largest terrestrial mammals of the Pleistocene, in a lake landscape on the North European plain, 125,000 years ago, as recently shown by a study of the Last Interglacial elephant assemblage from Neumark-Nord (Germany). With evidence for a remarkable focus on adult males and on their extended utilization, the data from this location are thus far without parallel in the archaeological record. Given their relevance for our knowledge of the Neanderthal niche, we investigated whether the Neumark-Nord subsistence practices were more than a local phenomenon, possibly determined by local characteristics.
View Article and Find Full Text PDFBr Dent J
October 2023
School of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy; Fondazione IRCCS San Gerardo dei Tintori, Monza, Italy.
On the occasion of the 250th anniversary of the birth of the Italian physician, Domenico Morichini (1773-1836), this study aims to commemorate this illustrious figure, who made a great contribution to the history of dentistry through his discovery of the presence of fluoride in dental enamel. Starting from a chemical analysis of the components of the enamel and osseous part of a fossilised elephant tooth discovered in Rome in 1802, Morichini demonstrated the presence of high amounts of fluoride, not only in these remains, but also in samples of human teeth. The Italian doctor, a Professor of Chemistry at the Sapienza University of Rome, also affirmed the importance of his discovery from a clinical perspective, as it enabled a better understanding of the chemical composition of enamel, changes in which he saw as the cause of most dental diseases.
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