Strontium isotope ratios (87Sr = 86Sr) of biogenic material such as bones and teeth reflect the local sources of strontium ingested as food and drink during their formation. This has led to the use of strontium isotope ratios as a geochemical tracer in a wide range of fields including archaeology, ecology, food studies and forensic sciences. In order to utilise strontium as a geochemical tracer, baseline data of bioavailable 87Sr = 86Sr in the region of interest are required, and a growing number of studies have developed reference maps for this purpose in various geographic regions, and over varying scales. This study presents a new data set of bioavailable strontium isotope ratios from rock and soil samples across Israel, as well as from sediment layers from seven key archaeological sites. This data set may be viewed and accessed both in an Open Science Framework repository (https://doi.org/10.17605/OSF.IO/XKJ5Y, Moffat et al., 2020) or via the IRHUM (Isotopic Reconstruction of Human Migration) database.
Sulfur dioxide [SO2(g)] is the most abundant sulfur-bearing volcanic gas species on Earth. From its magmatic origin at depth to expulsion at the surface via either persistent degassing or large explosive volcanic eruptions, SO2(g) interacts with silicate materials at elevated temperatures. Similar high-temperature reactions also occur in the volcanic systems and the atmospheres of Venus, the Galilean moon Io, and in Mars’ past, as well in industrial flue-gas processing. We present an experimental investigation of the reaction between SO2(g), glasses and supercooled melts in the system anorthite–diopside–albite (CaAl2Si2O8–CaMgSi2O6–NaAlSi3O8). The samples were exposed to SO2(g) at 600–800 °C for experimental durations of 10 min to 24 h. The reactions resulted in the formation of sulfate coatings and modified the near-surface composition of the silicate samples. The predominant sulfate reaction product is CaSO4, with hydrated MgSO4 or Na2SO4 also observed in some experiments. In the anorthite–diopside system, the reaction extent strongly depends on the temperature relative to the glass transition temperature (Tg). Above Tg, in reactions with supercooled melts, the reaction forms up to 20 times more sulfate. The overall rate of sulfate formation is controlled by the diffusive flux of Ca, Mg and Na from the increasingly depleted silicate to the surface where the reaction with SO2(g) occurs. The sulfate-forming reaction results in a volume increase relative to the unreacted silicate. When this reaction occurs in the subvolcanic environment it causes an increased molar volume that may close veins, reducing the permeability and decrease the SO2(g) flux at the surface. An increase in the SO2(g) flux would then result in the opening of new veins, which may be accompanied by seismic activity. Additionally, the change in molar volume may itself trigger seismicity. The strong preferential uptake of Ca into the sulfate reaction product results in a Si- and Al-enriched silicate. In the sulfate, the Ca component may be mobilized by secondary processes such as through the interaction with meteoric fluids. We recommend that the products of such gas–solid reactions should be the object of remote and robotic investigations of planetary environments with volcanic histories such as on Mars, Io, Venus and Mercury.
The burial mound of Le Tumulus des Sables, southwest France, contains archaeological artefacts spanning from the Neolithic to the Iron Age. Human remains have been found throughout the burial mound, however their highly fragmented state complicates the association between the burial mound structure and the archaeological material. Radiocarbon dating and isotopic analyses of human teeth have been used to investigate the chronology, diet and mobility of the occupants. Radiocarbon dating shows that the site was used for burials from the Neolithic to Iron Age, consistent with the range of archaeological artefacts recovered. δ13C and δ15N values (from dentine collagen) suggest a predominately terrestrial diet for the population, unchanging through time. 87Sr/86Sr (on enamel and dentine) and δ18O (on enamel) values are consistent with occupation of the surrounding region, with one individual having a δ18O value consistent with a childhood spent elsewhere, in a colder climate region. These results showcase the complex reuse of this burial mound by a mostly local population over a period of about 2000 years.
Strontium isotope ratios (87Sr/86Sr) of archaeological samples (teeth and bones) can be used to track mobility and migration across geologically distinct landscapes. However, traditional interpolation algorithms and classification approaches used to generate Sr isoscapes are often limited in predicting multiscale 87Sr/86Sr patterning. Here we investigate the suitability of plant samples and soil leachates from the IRHUM database (www. irhumdatabase.com) to create a bioavailable 87Sr/86Sr map using a novel geostatistical framework. First, we generated an 87Sr/86Sr map by classifying 87Sr/86Sr values into five geologically representative isotope groups using cluster analysis. The isotope groups were then used as a covariate in kriging to integrate prior geological knowledge of Sr cycling with the information contained in the bioavailable dataset and enhance 87Sr/86Sr predictions. Our approach couples the strengths of classification and geostatistical methods to generate more accurate 87Sr/86Sr predictions (Root Mean Squared Error=0.0029) with an estimate of spatial uncertainty based on lithology and sample density. This bioavailable Sr isoscape is applicable for provenance studies in France, and the method is transferable to other areas with high sampling density. While our method is a step forward in generating accurate 87Sr/86Sr isoscapes, the remaining uncertainty also demonstrates that finemodelling of 87Sr/86Sr variability is challenging and requires more than geological maps for accurately predicting 87Sr/86Sr variations across the landscape. Future efforts should focus on increasing sampling density and developing predictive models to further quantify and predict the processes that lead to 87Sr/86Sr variability.
Cisplatin is an effective anticancer drug; however, cisplatin use often leads to nephrotoxicity, which limits its clinical effectiveness. In this study, we determined the effect of dichloroacetate, a novel anticancer agent, in a mouse model of cisplatin-induced AKI. Pretreatment with dichloroacetate significantly attenuated the cisplatin-induced increase in BUN and serum creatinine levels, renal tubular apoptosis, and oxidative stress. Additionally, pretreatment with dichloroacetate accelerated tubular regeneration after cisplatin-induced renal damage. Whole transcriptome sequencing revealed that dichloroacetate prevented mitochondrial dysfunction and preserved the energy-generating capacity of the kidneys by preventing the cisplatin-induced downregulation of fatty acid and glucose oxidation, and of genes involved in the Krebs cycle and oxidative phosphorylation. Notably, dichloroacetate did not interfere with the anticancer activity of cisplatin in vivo. These data provide strong evidence that dichloroacetate preserves renal function when used in conjunction with cisplatin.
Strontium isotope ratios (87Sr / 86Sr) are a key geochemical tracer used in a wide range of fields including archaeology, ecology, food and forensic sciences. These applications are based on the principle that the Sr isotopic ratios of natural materials reflect the sources of strontium available during their formation. A major constraint for current studies is the lack of robust reference maps to evaluate the source of strontium isotope ratios measured in the samples. Here we provide a new data set of bioavailable Sr isotope ratios for the major geologic units of France, based on plant and soil samples (Pangaea data repository doi:10.1594/PANGAEA.819142). The IRHUM (Isotopic Reconstruction of Human Migration) database is a web platform to access, explore and map our data set. The database provides the spatial context and metadata for each sample, allowing the user to evaluate the suitability of the sample for their specific study. In addition, it allows users to upload and share their own data sets and data products, which will enhance collaboration across the different research fields. This article describes the sampling and analytical methods used to generate the data set and how to use and access the data set through the IRHUM database. Any interpretation of the isotope data set is outside the scope of this publication.
Geophysical Research Abstract of EGU General Assembly 2014, held 27 April 2 May, 2014 in Vienna, Austria. Disciplines Medicine and Health Sciences | Social and Behavioral Sciences Publication Details Willmes, M., James, H., Boel, C., Courtaud, P., Chancerel, A., McMorrow, L., Armstrong, R. A., Kinsley, L., Aubert , M., Eggins, S., Moffat, I. & Grun, R. (2014). Oxygen and strontium isotope tracing of human migration at the Bell Beaker site Le Tumulus des Sables, France. Geophysical Research Abstracts of EGU General Assembly 2014 (pp. 1-1). UK: ADS. Authors Malte Willmes, Hannah James, Ceridwen Boel, Patrice Courtaud, Antoine Chancerel, Linda McMorrow, Richard A. Armstrong, Leslie Kinsley, Maxime Aubert, Stephen Eggins, Ian Moffat, and Rainer Grun This conference paper is available at Research Online: http://ro.uow.edu.au/smhpapers/2060 Geophysical Research Abstracts Vol. 16, EGU2014-4763, 2014 EGU General Assembly 2014 © Author(s) 2014. CC Attribution 3.0 License. Oxygen and strontium isotope tracing of human migration at the Bell Beaker site Le Tumulus des Sables, France. Malte Willmes (1), Hannah James (1), Ceridwen Boel (1,2), Patrice Courtaud (3), Antoine Chancerel (4), Linda McMorrow (1), Richard Armstrong (1), Les Kinsley (1), Maxime Aubert (1,5), Stephen Eggins (1), Ian Moffat (1,6), and Rainer Grun (1) (1) The Australian National University, Earth Environment, Research School of Earth Sciences, Canberra, Australia (malte.willmes@anu.edu.au), (2) University of New South Wales, School of Biological, Earth and Environmental Sciences, Evolution and Ecology Research Centre, (3) University of Bordeaux, CNRS, MCC, PACEA UMR5199 F-33400 Talence, France, (4) Musee National de Prehistoire, 24 Eyzies-de-Tayac, France, (5) University of Wollongong, School of Earth and Environmental Sciences, Centre for Archaeological Science, Wollongong 2522, NSW, Australia, (6) Flinders University, Department of Archaeology, Adelaide, 5000, SA, Australia Oxygen (δO) and strontium (Sr/Sr) isotopes were used as tools to investigate human migration at the early Bell Beaker site (2500-2000 BC) Le Tumulus des Sables, Saint-Laurent-Medoc, south-west France. The O and Sr isotope ratios measured in tooth enamel record the average dietary isotope signature ingested by that individual during their childhood. When this data is compared to the isotope signature of the burial site it can be used to indicate if the individual migrated into this area during their lifetime. The O isotopic composition of meteoric water changes depending on climate, temperature and quantity of precipitation. O isotope ratios in skeletal and dental remains are related to body water, which in turn is influenced by diet, physiology and climate. Most of the water consumed by large mammals comes from drinking water, typically sourced locally. Sr isotope ratios on the other hand vary between different geologic regions, depending on their age and composition. Sr is released through weathering and transported into the soil, ground and surface water, where it becomes available for uptake by plants, enters the food cycle and eventually ends up in skeletal and dental tissue where it substitutes for calcium. We analysed the teeth of 18 adult and 8 juvenile disarticulated skeletons from Le Tumulus des Sables. O isotopes were analysed in-situ by Sensitive High Resolution Ion Micro Probe (SHRIMP).The Sr isotope analysis involved drilling a 0.2-0.5 mg sample of enamel from the tooth. The Sr was then chemically separated and analysed by Thermal Ionization Mass Spectrometry (TIMS). These results were then compared to the O isoscape of Europe and bioavailable Sr isotope data (fauna, plants, soils) from the IRHUM database. We found that most of the individuals at Le Tumulus des Sables show O and Sr isotope ratios corresponding to the local environmental signal and we interpret these as part of the local population. 3 adults however show slightly higher Sr/Sr ratios, which correspond to a clay and limestone unit in close proximity (<25 km) to the burial site, suggesting some limited mobility. In conclusion the application of O and Sr isotopes has allowed us to investigate mobility at this site and offers an additional string of evidence to interpret the mobility or lack of it of Bell Beaker populations in prehistoric Europe.