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Tandem probe analysis mode for synchrotron XFM: doubling throughput capacity
(American Chemical Society (ACS), 2022-03-22) Doolette, CL; Howard, DL; Afshar, N; Kewish, CM; Paterson, DJ; Huang, J; Wagner, S; Santner, J; Wenzel, WW; Raimondo, T; De Vries Van Leeuwen, AT; Hou, L; van der Bom, F; Weng, H; Kopittke, PM; Lombi, E
Synchrotron-based X-ray fluorescence microscopy (XFM) analysis is a powerful technique that can be used to visualize elemental distributions across a broad range of sample types. Compared to conventional mapping techniques such as laser ablation inductively coupled plasma mass spectrometry or benchtop XFM, synchrotron-based XFM provides faster and more sensitive analyses. However, access to synchrotron XFM beamlines is highly competitive, and as a result, these beamlines are often oversubscribed. Therefore, XFM experiments that require many large samples to be scanned can penalize beamline throughput. Our study was largely driven by the need to scan large gels (170 cm2) using XFM without decreasing beamline throughput. We describe a novel approach for acquiring two sets of XFM data using two fluorescence detectors in tandem; essentially performing two separate experiments simultaneously. We measured the effects of tandem scanning on beam quality by analyzing a range of contrasting samples downstream while simultaneously scanning different gel materials upstream. The upstream gels were thin (<200 μm) diffusive gradients in thin-film (DGT) binding gels. DGTs are passive samplers that are deployed in water, soil, and sediment to measure the concentration and distribution of potentially bioavailable nutrients and contaminants. When deployed on soil, DGTs are typically small (2.5 cm2), so we developed large DGTs (170 cm2), which can be used to provide extensive maps to visualize the diffusion of fertilizers in soil. Of the DGT gel materials tested (bis-acrylamide, polyacrylamide, and polyurethane), polyurethane gels were most suitable for XFM analysis, having favorable handling, drying, and analytical properties. This gel type enabled quantitative (>99%) transmittance with minimal (<3%) flux variation during raster scanning, whereas the other gels had a substantial effect on the beam focus. For the first time, we have (1) used XFM for mapping analytes in large DGTs and (2) developed a tandem probe analysis mode for synchrotron-based XFM, effectively doubling throughput. The novel tandem probe analysis mode described here is of broad applicability across many XFM beamlines as it could be used for future experiments where any uniform, highly transmissive sample could be analyzed upstream in the "background"of downstream samples. © 2022 The Authors. Published by American Chemical Society.
Variability and morphological peatures of Woolly Rhinoceros skulls (Coelodonta antiquitatis (Blumenbach 1799)) from Northeastern Asia in the late Pleistocene
(Pleiades Publishing, 2021-12) Puzachenko, AY; Kirillova, IV; Shidlovsky, FK; Levchenko, VA
Abstract: We studied 63 woolly rhinoceros skulls from the northeast of Russia (northwestern Chukotka, northeastern Yakutia) housed in the collection of the “Ice Age” Museum-Theatre, Moscow. Both sexual dimorphism and size/shape variability of woolly rhinoceros skulls are explored using univariate and multivariate statistics for the first time. Peculiarities of the variability, which are probably related to gender, are expressed in (1) different sets of skull variables the variability of which does not depend on “general size” variations and (2) differences in skull allometry in males and females. The structure of morphological variability is discussed. Statistically significant morphological heterogeneity is detected within the male and female samples. This is shown to be the consequence of the presence of two size groups that are not related to individual age. Based on published radiocarbon dates, it is hypothesized that there was a decrease in skull size in the woolly rhinoceros is at the end of megainterstadial (MIS) 3 to the early Last Glacial Maximum MIS 2 in northeastern Asia. To test this hypothesis, new radiocarbon dates of the studied specimens are needed. © 2024 Springer Nature.
Size‐dependent penetration of nanoparticles in tumor spheroids: a multidimensional and quantitative study of transcellular and paracellular pathways
(Wiley, 2023-10-11) Chen, W; Wang, WQ; Xie, Z; Centurion, F; Sun, B; Paterson, DJ; Tsao, SCH; Chu, D; Shen, Y; Mao, G; Gu, Z
Tumor penetration of nanoparticles is crucial in nanomedicine, but the mechanisms of tumor penetration are poorly understood. This work presents a multidimensional, quantitative approach to investigate the tissue penetration behavior of nanoparticles, with focuses on the particle size effect on penetration pathways, in an MDA‐MB‐231 tumor spheroid model using a combination of spectrometry, microscopy, and synchrotron beamline techniques. Quasi‐spherical gold nanoparticles of different sizes are synthesized and incubated with 2D and 3D MDA‐MB‐231 cells and spheroids with or without an energy‐dependent cell uptake inhibitor. The distribution and penetration pathways of nanoparticles in spheroids are visualized and quantified by inductively coupled plasma mass spectrometry, two‐photon microscopy, and synchrotron X‐ray fluorescence microscopy. The results reveal that 15 nm nanoparticles penetrate spheroids mainly through an energy‐independent transcellular pathway, while 60 nm nanoparticles penetrate primarily through an energy‐dependent transcellular pathway. Meanwhile, 22 nm nanoparticles penetrate through both transcellular and paracellular pathways and they demonstrate the greatest penetration ability in comparison to other two sizes. The multidimensional analytical methodology developed through this work offers a generalizable approach to quantitatively study the tissue penetration of nanoparticles, and the results provide important insights into the designs of nanoparticles with high accumulation at a target site. ©2023 The Authors. Small published by Wiley-VCH GmbH. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.
Moisture isotopes in the biosphere and atmosphere (MIBA) in Australia: a priori estimates and preliminary observations of stable water isotopes in soil, plant and vapour for the Tumbarumba field campaign
(Elsevier, 2006-05) Twining, JR; Stone, DJM; Tadros, CV; Henderson-Sellers, A; Williams, AG
An integral part of isotopes in the Program for Intercomparison of Land-surface Parameterisation Schemes (iPILPS) [Henderson-Sellers, A., in press. Improving land-surface parameterization schemes using stable water isotopes; introducing the iPILPS initiative. Global and Planetary Change, in press] is that the models' outputs be evaluated against measured values of δ2H and δ18O in the various simulated environmental compartments. This paper outlines the steps taken in Australia to initiate measurement of these stable water isotopes (SWIs) in the field, at a cool-temperate forest site in S.E. Australia near Tumbarumba, specifically to facilitate the model evaluation process. The selected sampling methodologies are detailed within the context of a conceptual model developed to describe the land-atmosphere exchange systems. This model has also been used to make a priori estimations of the isotopic values to be expected in each measured sub-system. As the data resulting from the Tumbarumba field campaign emerge, they will be compared with these working hypotheses to evaluate and, where necessary, amend the conceptual model. Initial comparisons based on preliminary data are presented here. The new observations derived in March 2005 should allow the land surface schemes used in weather forecast and climate change models to better reflect the environments for which they are attempting to make predictions. © 2006 Elsevier B.V.
Predicted CO2 water rock reactions in naturally altered CO2 storage reservoir sandstones, with interbedded cemented and coaly mudstone seals
(Elsevier, 2022-03-15) Pearce, JK; Dawson, GW; Golding, SD; Southam, G; Paterson, DJ; Brink, F; Underschultz, JR
Geological storage of CO2 captured from industrial processes such as coal combustion or from direct air capture is part of the transition to low emissions. The Jurassic Precipice Sandstone of the southern Surat Basin, Queensland, Australia, is undergoing feasibility studies for industrial scale CO2 geological storage, however regional data has so far been lacking. Precipice Sandstone reservoir drill core samples from the Southwood 1 and Tipton 153 wells in the southern Surat Basin include favourably quartz rich sandstone regions with quartz grain fracturing. A mudstone layer is also present in the reservoir. The overlying lower section of the Evergreen Formation seals consist of clay rich sandstones, interbedded mudstones, coal layers, Fe-Mg-Mn siderite, and Mg-calcite cemented sandstones. K-feldspars are weathered creating localised secondary porosity and pore filling kaolinite and illite. Layers of coal, pore filling cements, and framework grain compaction introduce vertical heterogeneity. Heavy minerals including pyrite, mixed composition sulphides, and barite are associated with disseminated coals in mudstones. Precipice Sandstone mercury intrusion porosities (MIP) ranged from 9 to 22% with favourably low reservoir injection threshold pressures, and the QEMSCAN measured open porosity between 2 and 22%. Evergreen Formation seal porosities were 7.5 to 16% by MIP or 1 to 19% by QEMSCAN, with the smallest pore throat distribution associated with the low permeability coal rich mudstone. Synchrotron XFM shows Rb mainly hosted in K-feldspars and muscovite, with metals including Mn mainly hosted in siderite. Zn and As are present in sulphides; and calcite and apatite cements mainly hosted Sr. Twenty kinetic geochemical CO2-water-rock models were run for 30 and 1000 years with Geochemist Workbench, with calcite and siderite initially dissolving. In the Precipice Sandstone reservoir variable alteration of carbonates, feldspars and chlorite to kaolinite, silica, siderite and smectite were predicted with the pH remaining below 5.5. CO2 was mineral trapped through alteration of chlorite to siderite in three of the four cases, with −0.02 to 1.43 kg/m3 CO2 trapped after 1000 years. In the calcite and siderite cemented Evergreen Formation seal, plagioclase conversion to ankerite trapped the most CO2 with 2.6 kg/m3 trapped after 1000 years. The Precipice Sandstone in both wells appears to be generally suitable as a storage reservoir, with mineral trapping predicted to mainly occur in the overlying lower Evergreen Formation and in interbedded mudstones. Heterogeneity in interbedded sandstone, mudstone, and coal layers are likely to act as baffles to CO2 and encourage mineral trapping. Quartz grain fractures may influence preferential migration pathways in the reservoir but this would need future experimental investigation. Experimental CO2 water rock reactions to understand porosity and permeability changes were out of scope here but are recommended in future validation, along with investigating the potential for CO2 adsorption trapping in coal and mudstone layers. © 2022 Elsevier B.V. All rights reserved.

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