Laser Ablation Inductively Coupled Plasma Mass Spectrometry Research Articles

The impact of corrosion on the adsorption of gaseous Hg0 onto the surface of steels: Implications for decommissioning in the oil and gas industry

The rate of decommissioning of global oil and gas production facilities will accelerate over coming decades, as mature developments reach the end of use, and consumers transition towards renewable energy. Decommissioning strategies should include thorough environmental risk assessments which consider contaminants which are known to be present in oil and gas systems. Mercury (Hg) is a global pollutant that occurs naturally in oil and gas reservoirs. However, knowledge of Hg contamination in transmission pipelines and process equipment is limited. We investigated the potential for accumulation of Hg0 within production facilities, particularly those transporting gases, by considering the deposition of Hg onto steel surfaces from the gas phase. Following incubation experiments in a Hg saturated atmosphere; fresh API 5L‐X65 and L80–13Cr steels were found to adsorb 1.4 × 10−5 ± 0.04 × 10−5 and 1.1 × 10−5 ± 0.04 × 10−5 g m−2, respectively, while corroded samples of the same steels adsorbed 0.12 ± 0.01 and 0.83 ± 0.02 g m−2; an increase in adsorbed mercury by four orders of magnitude. The association between surface corrosion and Hg was demonstrated by laser ablation ICPMS. The levels of Hg measured on the corroded steel surfaces indicates a potential environmental risk; therefore, mercury speciation (including the presence of ß-HgS, not considered in this study), concentrations and cleaning methods should be considered when developing oil and gas decommissioning strategies.

Microspatial distribution of trace elements in feline dental hard tissues: early life exposure to essential and toxic elements.

Trace elements play a key role in dental tissue development, as dental hard tissues accumulate both essential and toxic trace elements during mineralization. Characterization of the spatial accumulation pattern of trace elements may provide insight into exposure to toxic elements over time and to the nature of disease processes affecting the hard dental tissues. Here, we present the first report of the use of laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) to map the microspatial distribution of multiple trace elements, essential and toxic, across feline dental hard tissues. Eleven teeth were extracted from 8 cats. Nine teeth were from 7 cats diagnosed with idiopathic tooth resorption on intraoral radiographs prior to extraction. Two teeth were included from a cadaver that had no signs of tooth resorption on intraoral radiographs. The normal dental tissue was analyzed from each sample using LA-ICP-MS to map the microspatial distribution of essential and toxic trace elements across feline enamel, dentin, and cementum. Results showed a higher accumulation of barium and strontium in coronal dentin as compared to root dentin. The timing of the accumulation mirrors nursing timelines seen in teeth from human and non-human primates, consistent with barium and strontium being sourced from maternal milk. Results also showed a higher uptake of lead in the coronal dentin, suggesting this lead exposure was likely passed from mother to offspring. This work characterizes a baseline for elemental distribution in feline teeth linked to early life exposure to toxic elements such as lead and provides a framework for future studies investigating long-term environmental exposures to trace elements, essential and toxic, and their involvement in feline systemic and dental diseases.

Monazite and xenotime petrochronologic constraints on four Proterozoic tectonic episodes and ca. 1705 Ma age of the Uncompahgre Formation, southwestern Colorado, USA

Abstract The Proterozoic tectonic evolution of the southwestern USA remains incompletely understood due to limited constraints on the timing and conditions of the tectono-metamorphic phases and depositional age of metasedimentary successions. We integrated multi-scale compositional mapping, petrologic modeling, and in situ geochronology to constrain pressure-temperature-time paths from samples of Paleoproterozoic basement gneisses and overlying quartzites in southwestern Colorado, USA. Basement gneiss from the western Needle Mountains records metamorphic conditions of 600 °C at 0.75 GPa at 1764 ± 9 Ma and ~575 °C at 1741 ± 10 Ma. Gneiss sampled from drill core near Pagosa Springs, Colorado, records conditions of 700 °C at 1748 ± 9 Ma, 800 °C at 1.1 GPa at 1650 ± 40 Ma, 540 °C at 1570 ± 36 Ma, and 440 °C at 1424 ± 12 Ma. The Uncompahgre Formation was deposited at ca. 1705 Ma, as constrained by detrital monazite (1707 ± 8 Ma) and xenotime (1692 ± 40, 1725 ± 50 Ma), metamorphic xenotime (1650 ± 10 Ma), and published 40Ar/39Ar and detrital zircon data. Compositions of ca. 1705 Ma detrital monazite and xenotime are consistent with derivation from a garnet-bearing source in the Yavapai orogenic hinterland. The Vallecito Conglomerate and Uncompahgre Formation record macroscopic folding and greenschist-facies metamorphism at 1650 ± 10 Ma and temperatures of 270 °C to >570 °C at 1470–1400 Ma. Laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) zircon geochronology yielded dates of 1775 ± 18 Ma from the Twilight Gneiss and 1696 ± 7 Ma from the Bakers Bridge Granite, supporting previous isotope dilution–thermal ionization mass spectrometry (ID-TIMS) dates. The Eolus Granite yielded a date of 1463 ± 6 Ma, which is older than previous 1.44–1.43 Ga ID-TIMS dates. The newly dated granite of Cataract Gulch is 1421 ± 12 Ma. In situ analysis of detrital and meta-morphic monazite and xenotime, igneous zircon, and quantitative thermobarometry, integrated with previously published constraints, indicate multiple tectonic episodes after the emplacement of 1800–1760 Ma arc-related rocks. The region experienced greenschist- to amphibolite-facies metamorphism (M1) from 1760 Ma to 1740 Ma, which was followed by the intrusion of granites at 1730–1695 Ma and deposition of the Uncompahgre Formation at ca. 1705 Ma, contemporaneous with the Yavapai orogeny. Metamorphism at 1680–1600 Ma was characterized by greenschist-facies conditions near Ouray, Colorado, and granulite-facies conditions near Pagosa Springs (M2) during the Mazatzal orogeny. From 1470 Ma to 1400 Ma, greenschist- to amphibolite-facies metamorphism (M3) and largely granitic plutonism occurred during the protracted Picuris orogeny. These results demonstrate the power of monazite and xenotime analyses to constrain depositional ages, provenance, and pressure-temperature-time (P-T-t) paths to resolve the compound orogenic history that is characteristic of most mountain belts.

Insights into the secondary glass production in Roman Aquileia: A preliminary study

A set of 29 glass shards, selected from numerous ones recovered in 2017 in Aquileia (NE Italy), was studied to provide evidence of local glass production for that specific area in antiquity. These shards can be dated between the 1st and the 4th century AD. The chemical composition of glass samples was obtained using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) that enables to quantify the concentration of major, minor, and trace elements needed to investigate provenance and compositional groups and sometimes to suggest a chronological frame of the samples. To ensure that the samples are homogeneous enough to perform accurate quantification, some of them were also analysed by instrumental neutron activation analysis (INAA). Most of the chunks, working wastes, and artefact shards considered in this work exhibited similarities among them in terms of composition, which likely indicates that glass working activities were practised at the site of recovery. The analyses demonstrated the presence of both recycled glass and primary glass. Interestingly, the compositional data of raw primary glass point to both Syro-Palestinian and Egyptian regions as sourcing areas, confirming the role of the Roman city of Aquileia as a network node for the trade of goods. In addition, some particularly coloured glass fragments showed a composition typical of glass produced starting from the 1st or 2nd century AD, requiring specific types of furnaces and procedures for its manufacture, and suggesting the possibility of local highly-specialised production. The preliminary results of this work strengthen the hypothesis that Aquileia was a thriving centre, either for working primary glass or for glass recycling and production of objects with particular colours.

The genetic association between vein and skarn type tungsten mineralization in the Yaogangxian tungsten deposit, South China: Constraints from LA-ICP-MS analysis of individual fluid inclusion

The large-scale Yaogangxian W deposit, located in central of the Nanling metallogenic belt, South China, comprises independent quartz vein-type and skarn-type W mineralization. Wolframite-bearing quartz veins occur invariably in metasandstone and slate to the northwest of the Yaogangxian granitic intrusion, whereas scheelite-skarn are mainly hosted by the limestone to the east. The vertical extension of single wolframite-bearing quartz vein can reach up to 1000 m and we focused on the vein samples collected from the deepest level (26 level) which likely recorded early magmatic fluids. For skarn mineralization, two scheelite precipitation stages were recognized, namely scheelite-1 in retrograde stage and scheelite-2 from sulfide-stage. To reveal the fluid sources and characteristics of two mineralizing systems, detailed petrography and microthermometry analyses were carried out on fluid inclusion assemblages (FIA) in scheelite, wolframite and their coexisting quartz. Fluid compositions were obtained from individual fluid inclusion (FI) in ore and gangue minerals via laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) analysis. These data aid elucidation on the source and nature of fluids in the two distinct W mineralization styles. The chemical compositions of FIs hosted in wolframite and scheelite points to a common magmatic source. The fluid in the scheelite ore section exhibits lower As and B than the wolframite ore section, indicating that boiling may have occurred at early skarn stage. Fluid evolution in the two mineralizing systems suggest that formation of diverse W mineralization styles is mainly controlled by different host lithology and fluid processes. In the wolframite ore section, ore-forming fluid recorded in the deepest level of vein show elevated As, B, K and Rb contents than previously reported ore-forming fluid obtained from the tip of the vein. This likely indicate absence of intensive fluid immiscibility in the deep during wolframite formation, which may rather be accompanied by fluid-rock interaction. In the scheelite ore section, constant injection of meteoric water is revealed. FI hosted in scheelite-1 and 2 exhibit similar compositions, and the lower K content in scheelite-2 fluid is thought to be caused by sericitization in the retrograde stage skarn. The Mo content of scheelite decreased from the retrograde stage to sulfide-stage, indicating a decrease in oxygen fugacity. Based on these conclusion and previous geological and geochronological studies, we propose a metallogenic model of the coupled wolframite-quartz vein and scheelite-skarn mineralization.

Impact of an SLC30A8 loss-of-function variant on the pancreatic distribution of zinc and manganese: laser ablation-ICP-MS and positron emission tomography studies in mice.

Common variants in the SLC30A8 gene, encoding the secretory granule zinc transporter ZnT8 (expressed largely in pancreatic islet alpha and beta cells), are associated with altered risk of type 2 diabetes. Unexpectedly, rare loss-of-function (LoF) variants in the gene, described in heterozygous individuals only, are protective against the disease, even though knockout of the homologous SLC30A8 gene in mice leads to unchanged or impaired glucose tolerance. Here, we aimed to determine how one or two copies of the mutant R138X allele in the mouse SLC30A8 gene impacts the homeostasis of zinc at a whole-body (using non-invasive 62Zn PET imaging to assess the acute dynamics of zinc handling) and tissue/cell level [using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) to map the long-term distribution of zinc and manganese in the pancreas]. Following intravenous administration of [62Zn]Zn-citrate (~7 MBq, 150 μl) in wild-type (WT), heterozygous (R138X+/-), and homozygous (R138X+/+) mutant mice (14-15 weeks old, n = 4 per genotype), zinc dynamics were measured over 60min using PET. Histological, islet hormone immunohistochemistry, and elemental analysis with LA-ICP-MS (Zn, Mn, P) were performed on sequential pancreas sections. Bulk Zn and Mn concentration in the pancreas was determined by solution ICP-MS. Our findings reveal that whereas uptake into organs, assessed using PET imaging of 62Zn, is largely unaffected by the R138X variant, mice homozygous of the mutant allele show a substantial lowering (to 40% of WT) of total islet zinc, as anticipated. In contrast, mice heterozygous for this allele, thus mimicking human carriers of LoF alleles, show markedly increased endocrine and exocrine zinc content (1.6-fold increase for both compared to WT), as measured by LA-ICP-MS. Both endocrine and exocrine manganese contents were also sharply increased in R138X+/- mice, with smaller increases observed in R138X+/+ mice. These data challenge the view that zinc depletion from the beta cell is the likely underlying driver for protection from type 2 diabetes development in carriers of LoF alleles. Instead, they suggest that heterozygous LoF may paradoxically increase pancreatic β-cell zinc and manganese content and impact the levels of these metals in the exocrine pancreas to improve insulin secretion.

Mineralogy and elemental geochemistry of pyrite coal-balls, Datong Coalfield, Shanxi Province, China: Implications for differentiation mechanism

The pyrite coal-balls found in No.9 coal of Taiyuan Formation in Dongzhouyao Mine of Datong Coalfield were selected to investigate its mineralogy and elemental geochemistry using optical microscope observation, scanning electron microscopy combined with an energy-dispersive X-ray spectrometer (SEM-EDX), inductively coupled plasma mass spectrometry analysis (ICP-MS), laser ablation inductively-coupled plasma mass spectrometry (LA-ICP-MS), and electron probe micro-analysis (EPMA). Due to the high content of pyrite, the major-element oxides in the coal-ball samples were mainly Fe2O3, with an average of 62.68 %. LA-ICP-MS results showed that coal-balls were enriched in Tl (CC = 32.79), Pb (CC = 9.22), and Mo (CC = 2.07), while the coals in the same layer were enriched in Ga (CC = 5.31), Tl (CC = 3.66), and Li (CC = 2.27). Affinities to S or Fe and the variation of elemental concentration in the environment during the formation of coal-balls were the primary factor of the elemental differentiation between coals and coal-balls, as well as within coal-balls. The coal-balls formed in four stages in a marine-continental transition environment, with Fe from terrestrial sources and S from marine phases, and its physical origin is basically consistent with that of some Carboniferous-Permian coals in the Datong Coalfield. According to the formation sequence and geochemical characteristics, four periods of pyrite coal-balls evolution have been proposed.

Early Mesozoic orogenic gold mineralization in the North Qinling Terrane: Insights from rutile U-Pb, mica and K-feldspar 40Ar/39Ar, and H-O-S-Pb isotopes of the Yangxie gold deposit

The North Qinling Terrane is located between China’s second largest, Early Cretaceous gold province (southern North China Craton) to the northeast and the third largest, Triassic gold province (western South Qinling Terrane) to the southwest. However, only several small- to medium-sized Au deposits and occurrences have been found so far in the North Qinling Terrane, and their genesis and possible links with the gold mineralization in the above two large gold provinces remain unclear. In this study, we present a comprehensive geochronology, stable and radiogenic isotope geochemistry study of the Yangxie gold deposit in the North Qinling Terrane to provide new insights into gold genesis in the North Qinling Terrane and its genetic relations to the neighboring gold provinces. The Yangxie gold deposit consists of quartz-sulfides veins that are hosted by NW- and NE-striking brittle faults cutting amphibolite- to granulite-facies metamorphic rocks of the Paleoproterozoic to Neoproterozoic Qinling Group. Gold mineralization is represented by four paragenetic stages consisting of milky quartz-K-feldspar (I), light grey quartz-pyrite (II), light grey quartz-polymetallic sulfides (III), and quartz-calcite (IV). Gold was deposited mainly in stages II and III, forming abundant native gold grains that occur as inclusions in pyrite, microfracture infillings in sulfide minerals, or interstitial growths to other ore and gangue minerals. Ore-related alteration assemblages comprise mainly quartz, sericite, muscovite, K-feldspar, and calcite. Hydrothermal rutile is widely recognized in gold ores and texturally intergrown with gold-bearing pyrite and other alteration minerals, indicating synchronous precipitation of rutile and gold. Laser ablation ICP-MS U-Pb dating on two rutile samples yield reproducible dates of 214.6 ± 5.5 Ma (MSWD = 0.82, 2σ) and 210.1 ± 6.9 Ma (MSWD = 1.3, 2σ), which are interpreted as the time of gold deposition. 40Ar/39Ar dating of sericite, muscovite, and K-feldspar from the alteration assemblages yield more scattered and younger dates ranging from 199.8 ± 1.1 to 119.3 ± 0.6 Ma, which are considered as the cooling ages of the deposit related to later tectonothermal events. Oxygen and hydrogen isotopes of ore-related quartz and extracted fluid inclusion waters are 10.4 ∼ 15.0 and −87.7 ∼ -67.2 per mil, respectively. Pyrite and galena have variable δ34S values ranging from −9.4 to 0.5 per mil. These sulfides have lead isotopic compositions of 17.956–18.067 for 206Pb/204Pb, 15.565–15.621 for 207Pb/204Pb, and 38.045–38.301 for 208Pb/204Pb. The isotope data collectively suggest that the ore-forming fluids and metals were derived from the devolatilization of the early Paleozoic sedimentary rocks distributed in the North Qinling Terrane. The results presented here, combined with independent studies, show that the Yangxie deposit was a product of the Late Triassic orogenic gold mineralization event that formed the western South Qinling gold province. Recognition of the Late Triassic Yangxie gold deposit suggests that faults within and around the metamorphosed Paleozoic sedimentary rocks and subsidiary faults affiliated to the Shangdan Suture in the North Qinling Terrane could be favorable targets for further Triassic orogenic gold exploration.

Isotope dilution LA-ICP-MS for quantitative imaging of trace elements in mouse brain sections

Isotope dilution (ID) analysis is considered one of the most accurate quantitative methods. However, it has not been widely applied to the quantitative imaging of trace elements in biological samples using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), mainly because of difficulties in homogeneously mixing enriched isotopes (the spike) with the sample (e.g., a tissue section). In this study, we present a novel method for the quantitative imaging of trace elements (copper and zinc) in mouse brain sections using ID-LA-ICP-MS. We used an electrospray-based coating device (ECD) to evenly distribute a known amount of the spike (65Cu and 67Zn) on the sections. The optimal conditions for this process involved evenly distributing the enriched isotopes on mouse brain sections mounted on indium tin oxide (ITO) glass slides using the ECD with the 10 mg g−1 ɑ-cyano-4-hydroxycinnamic acid (CHCA) in methanol at 80 °C. The mass of the spiked isotopes and the tissue sections on the ITO slides was calculated by weighing them on an analytical balance. Quantitative images of Cu and Zn in Alzheimer's disease (AD) mouse brain sections were obtained using ID-LA-ICP-MS. These imaging results showed that Cu and Zn concentrations in various brain regions typically ranged from 10 to 25 μg g−1 and 30–80 μg g−1, respectively. But it is worth noting that the hippocampus contained up to 50 μg g−1 of Zn, while the cerebral cortex and hippocampus had Cu contents as high as 150 μg g−1. These results were validated by acid digestion and solution analysis with ICP-MS. The novel ID-LA-ICP-MS method provides an accurate and reliable means for quantitative imaging of biological tissue sections.

LA-ICP-MS Trace Element Geochemistry of Sphalerite and Metallogenic Constraints: A Case Study from Nanmushu Zn–Pb Deposit in the Mayuan District, Shaanxi Province, China

The Nanmushu Zn–Pb deposit is a large-scale and representative deposit in the Mayuan ore field on the northern margin of the Yangtze Block. This study investigates the trace element geochemistry of sphalerite from this deposit using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). The results show that the main trace elements in sphalerite include various trace elements, such as Mn, Fe, Cu, Ga, Ge, Ag, Cd, Pb, Co, Hg, Tl, In, Sn, and Sb. Among them, Ag, Ge, Cd, and Cu are valuable components that may be recovered during mineral processing or smelting techniques. The histograms, LA-ICP-MS time-resolved depth profiles, and linear scan profiles indicated that most trace elements occur in sphalerite as isomorphs, while partial Pb, Fe, and Ag occur as tiny mineral inclusions. The correlation diagrams of trace elements revealed that Fe2+, Mn2+, Pb2+, and Tl3+ can substitute Zn2+ in sphalerite through isomorphism. In sphalerite, Cd2+ and Hg2+ together or Mn2+, Pb2+, and Tl3+ together can replace Zn2+, i.e., ((3Mn, 3Pb, 2Tl)6+, 3(Cd, Hg)2+) ↔ 3Zn2+. Moreover, there is a mechanism of Ge4+ with Cu+ or Ga3+ with Cu+ replacing Zn2+ in the Nanmushu deposit, i.e., Ge4+ + 2Cu+ ↔ 3Zn2+ or 2Ga3+ + 2Cu+ ↔ 4Zn2+. Furthermore, the trace element compositions indicate that the Nanmushu Zn mineralization occurred under low-temperature conditions (<200 °C) and should be classified as a Mississippi Valley-type (MVT) deposit. This study provides new insights into the occurrence and substitution mechanisms of trace elements in sphalerite and the metallogenic constraints of the Nanmushu deposit.

Early Islamic glass (7th- 10th centuries AD) in Unguja Ukuu, Zanzibar: A microcosm of a globalised industry in the early 'Abbasid period.

Eighty-two glass vessels, recovered from the excavations at the ancient Swahili settlement and port of Unguja Ukuu in Zanzibar, Eastern Africa, were analysed using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS). The results show that all of the glass samples are soda-lime-silica glass. Fifteen glass vessels belong to the natron glass type and are characterised by low MgO and K2O (<1.50%), suggesting they were made from natron, a mineral flux that was widely used during the Roman period and Late Antiquity. Sixty-seven glass vessels belong to the plant ash glass type, characterised by high magnesia and potash levels (>1.50%), suggesting plant ash was the main alkali flux. Based on the major, minor and trace elements, three different compositional groups were identified for the natron glass and three were identified for the plant ash glass: (1) UU Natron Type 1, (2) UU Natron Type 2, (3) UU Natron Type 3, (4) UU Plant ash Type 1, (5) UU Plant ash Type 2 and (6) UU Plan ash Type 3. Comparison with contemporary Middle Eastern glass groups shows that UU Natron Types 1, 2 and 3 correspond to Egypt II high Na2O, Levantine I and Levantine II respectively, while UU Plant ash Type 1 matches closely with Samarra Group 2. UU Plant ash Types 2 and 3 have unique chemical fingerprints that do not match any of the contemporary plant ash glass groups, but their chemical compositions show some affinity with the old Sassanian plant ash glass, suggesting a possible Mesopotamian provenance. Combined with existing research on early Islamic glass, the authors reveal a complex trading network in the globalisation of Islamic glass, particularly involving glass corresponding to modern Iraq and Syria, in the 7th- 9th centuries AD.

A shadow of ink: Test papers soaked in 4:7-diphenyl-1:10-phenanthroline as a carrier of elemental information for spectrochemical investigations of manuscripts by XRF, LA-ICP-MS and SIMS

In this study, X-Ray Fluorescence Spectrometry (XRF), Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) and Secondary Ion Mass Spectrometry (SIMS) have been used to assess the transfer of ions between iron-gall inks and indicator papers soaked in 4:7-diphenyl-1:10-phenanthroline. Such indicators are commonly used in the conservation practice to detect Fe(II) ions and diagnose a presence of ink corrosion phenomena in historical manuscripts. For this purpose four different model inks with variable Fe:Cu proportions were prepared on the basis of gall nuts extract mixed with FeSO4.7H2O, CuSO4.5H2O and Gum Arabic. Obtained results indicate that apart from the main components of inks (S, Fe and Cu) also other elements can migrate to indicator test papers. Collected XRF and LA-ICP-MS data were consistent in their potential for reconstructing major elemental composition of model inks on the basis of indirect analysis with indicator test papers. LA-ICP-MS extended the range of learning into the trace elemental composition, while SIMS allowed observations of structurally significant fragment ions (ML2+, ML+, M+) where L = 4:7-diphenyl-1:10-phenanthroline and M = Fe or Cu ions.

Hyperthermic Intrathoracic Chemotherapy (HITOC) Improves Malignant Pleural Mesothelioma Control Through a Tumor Specific Cytotoxic Immune Response

Abstract Background The management of malignant pleural mesothelioma (MPM) remains challenging with poor patient survival. Local therapies such as hyperthermic intrathoracic cisplatin (HITOC) have shown good tumor control in selected patients. HITOC was shown to increase MPM drug exposure while limiting systemic side effects but alternative mechanisms for HITOC are still lacking. Aims We hypothesized that HITOC induces an immune response directed against MPM which decreases cancer related mortality. Methods A perfusion circuit was downsized to administer cisplatin in the thoracic cavity of MPM bearing mice at normo (37°C, ITOC) or hyperthermic (39°C, HITOC) conditions for 30 minutes. Tumor platinum content and distribution were determined by inductively coupled plasma mass spectrometry (ICP-MS) and by laser ablation ICP-MS respectively. The impact of (H)ITOC on the MPM immune microenvironment was questioned using flow cytometry and immunohistochemistry. Tumor growth and survival was assessed in immunocompetent and T-cell deficient mice. Finally, the combination of HITOC with anti-CTLA-4 and anti-PD-1 antibodies was evaluated in immunocompetent animals. Results MPM tumor control and mouse survival were significantly improved by HITOC compared to controls (ITOC, saline 37 and 39°C). This correlated with higher tumor platinum content that was mainly located at the surface of tumors. Furthermore, HITOC enhanced MPM infiltration by cytotoxic T-cells and decreased the level of protumor (M2-like) macrophages at day 7. The beneficial impact of HITOC on tumor control and mice survival was lost in immunocompromised animals. Interestingly, HITOC significantly induced PD-1 and CTLA-4 immune checkpoint molecules expression and administration of dual immune checkpoint blockade after HITOC increased of almost two fold the median survival of the animals. Conclusions HITOC improves MPM control through a T lymphocyte immune mediated response. The potentiation of the immune checkpoint blockade response by HITOC opens new perspectives for the combination of immune checkpoint inhibitors with HITOC in clinic.

Electrochemical Stability Window and Electrolyte Breakdown Mechanisms of Lithium Lanthanum Titanate

Perovskite-type La0.57Li0.29TiO3 (LLTO) is a promising solid electrolyte material with high Li-ion conductivity. However, its experimental electrochemical stability window is not precisely known, and thus the compatibility with potential electrode materials is partly unclear. In this contribution, we present results from electrochemical and analytical experiments to elucidate the stability of LLTO when being polarized with Li-ion-blocking Pt electrodes. Above 2.5 V, a darkened color front starts moving from the cathode to the anode, leading to electrolyte degradation. While first-principles calculations predict the appearance of new phases as decomposition products, we find zones with modified defect chemical properties originating from the anode and cathode. The darkened zone forming at the cathode contains Ti3+ polarons with high mobility, which leads to a mixed ion-electron conductivity, already for a very small Li excess concentration. Next to the anode a spatially very confined, weakly conductive Li depletion zone forms. The spatially confined but substantial Li depletion near the anode could be quantified by analytical laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). In contrast to first-principles calculations, no new phases were found near the anode, according to synchrotron-based grazing incidence XRD measurements.

Building geochemical vectors with trace element compositions of sulfides in orogenic gold mineral systems in northern Finland

Exploring and discovering new ore deposits that supply the needed metals for our current societal transition to a green-energy and technologically advanced low-carbon future is becoming increasingly difficult. To fully convert the current system however, a significant increase of mining of minerals is required, particularly since current global mineral reserves are insufficient to cover the growing demand for a fossil fuel-free infrastructure. It is therefore even more important to develop and introduce new time-and cost-efficient exploration tools, which can be utilized in the discovery of new mineral deposits and applied in the early, or through advanced stages of mineral exploration. Given that Finland is one of the major EU countries that covers the supply chain for the EU battery industry, its metallogenic provinces are extensively tested and investigated by new exploration technologies. For this purpose, a comprehensive dataset of trace element contents in single grains of pyrite, pyrrhotite and chalcopyrite was compiled on the basis of results of laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) analyses. Samples were systematically collected from drill cores from orogenic Au-only and Au-base-metal deposits in the Paleoproterozoic Svecofennian orogenic belts in northern Finland. The objective of this dataset is to serve as a reference tool in heavy indicator minerals-based exploration. By performing correlation analysis with the symmetric pivot coordinates approach for compositional data, as well as principal component analysis, it is demonstrated how all analyzed sulfide species have the capacity to discriminate between Au-only and Au-base-metal deposit types, as well as occurrences of free Au versus refractory Au. Element pairs of symmetric coordinates most suitable for differentiating Au-only systems from Au-base-metal settings are Co/Au and Au/Se in pyrite; Ni/Bi and Se/As in pyrrhotite; and Ni/Ag, Ag/In, Se/Ag, Cr/Ag, Cr/In, Cr/Zn, Zn/Se and Sn/Se in chalcopyrite. Results from principal component analysis reveal that pyrites from Au-base-metal deposits are associated with the positive loadings of Se-As-Co onto PC1 and those from Au-only deposits with negative loadings of Bi-Sb-Te-Au and Ni onto PC1 and PC2, respectively. In the case of pyrrhotite, samples from Au-Co and Au-Cu deposits are clearly distinguished between the positive loadings of Hg-Se-Co onto PC1, and the negative loadings of Sb-Au-Bi-Ni onto PC1. Positive loadings of Ag-Se and Co along PC1 are indicative of chalcopyrite from Au-Co deposits, while negative loadings of Ni and Zn onto PC1 are pointing towards an origin from Au-Cu, as well as Au-only deposits. Additionally, when testing the indicator mineral method with recovered pyrites from till samples from the Peräpohja belt, a potential relationship with bedrock pyrites is successfully demonstrated. This study aims to present the versatility of sulfide trace elements in geochemical exploration, as it could complement the mineral exploration industry with a more efficient and less expensive practice for profitable deposit discovery.

Laser ablation mass spectrometry blast through detection in R.

Organisms that grow a hard carbonate shell or skeleton, such as foraminifera, corals or molluscs, incorporate trace elements into their shell during growth that reflect the environmental change and biological activity they experienced during life. These geochemical signals locked within the carbonate are archives used in proxy reconstructions to study past environments and climates, to decipher taxonomy of cryptic species and to resolve evolutionary responses to climatic changes. Here, we use laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) as a time-resolved acquisition to quantify the elemental composition of carbonate shells and skeletons. We present the LABLASTER (Laser Ablation BLASt Through Endpoint in R) package, which imports a single time-resolved LA-ICP-MS analysis, then detects when the laser has ablated through the carbonate as a function of change in signal over time and outputs key summary statistics. We provide two examples within the package: a fossil planktic foraminifer and a tropical coral skeleton. We present the first R package that automates the selection of desired data during data reduction workflows. This is achieved by automating the detection of when the laser has ablated through a sample using a smoothed time series, followed by removal of off-target data points. The functions are flexible and adjust dynamically to maximise the duration of the desired geochemical target signal, making this package applicable to a wide range of heterogenous bioarchives. Visualisation tools for manual validation are also included. LABLASTER increases transparency and repeatability by algorithmically identifying when the laser has either ablated fully through a sample or across a mineral boundary and is thus no longer documenting a geochemical signal associated with the desired sample. LABLASTER's focus on better data targeting means more accurate extraction of biological and geochemical signals.

High-resolution single pulse LA-ICP-MS mapping via 2D sub-pixel oversampling on orthogonal and hexagonal ablation grids – A computational assessment

Laser beam profiles in analytical laser ablation – inductively coupled plasma – mass spectrometry (LA-ICP-MS) instruments are in general homogenized to produce a flat-top beam profile. However, in practice, they are mostly super-Gaussian in nature, and for small laser beam sizes (<5 μm) they even approach a Gaussian profile. This implies that the amount of surface material sampled by the laser (=ablation volume) directly depends on the beam profile and ablation grid. By contraction of the ablation grid (=sub-pixel mapping) not only more accurate surface sampling is realized, but also a higher pixel density, an improved spatial resolution, and a better signal-to-noise ratio. Although LA sampling is predominantly performed on an orthogonal grid, hexagonal or staggered/interleaved sampling may further improve the image quality as regular hexagons are more compact than squares (=lower perimeter/area) and suffer less from orientation bias (=lower anisotropy). Due to the current limitations of LA stages in executing precise hexagonal sampling with small beam sizes, computational protocols were employed to simulate LA-ICP-MS mapping. Simulation was performed by discrete convolution using the crater profile as the kernel, followed by the application/addition of Poisson/Flicker noise related to the local concentration and instrumental sensitivity/noise. A freely accessible online app was developed (https://laicpms-apps.ki.si/webapps/home/) to study the effect of sampling grid contraction (orthogonal and hexagonal) on the image map quality (spatial resolution and signal-to-noise ratio) by virtual ablation of phantoms. Comparison of experimental LA-ICP-MS maps obtained through orthogonal and hexagonal sampling methods could only be performed using a beam size of 150 μm and a macroscale inkjet-printed resolution target. This was due to the unavailability of precise hexagonal sampling stages and microscale resolution targets, which prevented the use of smaller beam sizes.

A comparative study of fluid characteristics of W and Cu mineralization in the Shiweidong deposit, giant Dahutang ore field, South China: Evidence from LA-ICP-MS analysis of fluid inclusion

The Shiweidong W-Cu deposit, located within the giant Dahutang W-Cu ore field, contains quartz vein type W-Cu and veinlet-disseminated type W mineralization. These ore veins are mainly hosted in the Jinningian biotite granodiorite. Two distinct mineralization stages were identified in association with quartz, namely wolframite-quartz veins and chalcopyrite-scheelite-quartz association. The deposit represents an example of a complex of economically valuable W and Cu, with resources of 0.3 Mt WO3 and 0.24 Mt Cu. The characteristic and origin of the W and Cu mineralizing fluids remain debated. In our study, homogenization temperature (Th) and salinity were determined for fluid inclusions (FIs) in ore or associated gangue minerals. Additionally, we use the trace element compositions of fluid inclusions obtained by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) to clarify fluid characteristics responsible for W and Cu mineralization. Primary fluid inclusions (FIs) trapped in wolframite display high Th ranging from 305 to 352 °C and have moderate salinity from 3.2 to 5.0 wt% NaCl equiv., quartz associated with chalcopyrite exhibit a close syngenetic relationship, and a significant low-temperature (248 ∼ 271 °C) fluid was recorded by FIs in quartz. Wolframite-hosted FIs were characterized by high concentrations of incompatible lithophile element Cs and volatile elements including Li and B, indicating that W mineralization fluid was derived from highly fractionated granitic systems. All FIs in wolframite display the absence of Cu. In contrast, FIs hosted in quartz coexisting with chalcopyrite have the high Cu concentrations with average value of 1033 ppm. Giving the lower Cs content in FIs from quartz coexisting with chalcopyrite, we suggest that the Cu-rich ore-forming fluid released from a less fractionated magma. These results indicate that W and Cu mineralization at Shiweidong was introduced by distinct fluids. Fluid simple cooling is likely a major driving factor in wolframite formation, while fluid boiling accompanied chalcopyrite deposition. Our new findings illuminate that the existence of independent Cu mineralization events in the W deposit in northern Jiangxi.

Spatiotemporal variability in otolith elemental fingerprint and the potential to determine deepwater redfish (Sebastes mentella) origins and migrations in the Estuary and Gulf of St. Lawrence, Canada

Connectivity processes have major implications in defining the resiliency of fish populations to overexploitation. A preliminary estimate of population exchange rates can be done by identifying the natal origin of adult fish. In this study, otolith elemental fingerprints were used as natural marker of origins and movements of Deepwater redfish (Sebastes mentella) in the Gulf of St. Lawrence (GSL). We specifically targeted the strong 2011–2013 cohorts that supported the rapid recovery of the GSL stock after its collapse in the 1990s. Elemental fingerprints were extracted from the core (proxy for larval origin) and edge (proxy for capture location) of otoliths using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). We observed an East to West gradient in the multi-elemental fingerprint of the otolith edge in the GSL, as well as evidence of temporal variation between 2016 and 2018. Cluster analysis of the core fingerprint revealed the existence of two chemically distinct natal sources of variable contribution between the Saguenay Fjord, the western GSL and the eastern GSL. This new insight on the population structure of redfish in the GSL at an ecologically relevant scale constitutes important knowledge for the assessment and sustainable management of a key recovering resource.

Diffusion potentials in saturated hardened cement paste upon chloride exposure

The diffusion potentials can cause significant errors in corrosion-related investigations of reinforced concrete structures (half-cell potential mapping, potentiometric sensors). Therefore, an improved understanding of the diffusion potentials in cement-based materials is needed. This study investigates the permselective behavior and its implication for the arising diffusion potentials. A diffusion cell is used to study the diffusion potentials in hardened cement pastes with imposed NaCl gradients. The cement pastes consist of ordinary Portland cement (OPC) and blast furnace cement (BFC) with water-cement ratios of 0.30–0.70. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is used to determine the concentration profiles of Cl, Na, K and Ca in the cement pastes with a high spatial resolution (100 µm). For the BFC pastes, considerable differences in the Cl− and Na+ mobilities are found, indicating their permselective behavior. Despite the permselective behavior, the measured diffusion potentials are small (− 6 to + 3 mV) for all investigated cement pastes due to the high pH levels (13–14) in the pore solutions. However, when using the diffusion cell, the pH differences interfere with the measured diffusion potentials. The interfering pH differences need to be considered for an accurate measurement of the diffusion potentials in cement pastes.