I18-Microfocus Spectroscopy
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Diamond Proposal Number(s):
[32914]
Open Access
Abstract: As the demand for copper increases, processing increasingly low-grade ore has become a critical challenge. Most of these ores are dominated by aluminosilicate gangue minerals, among which Fe-bearing phyllosilicates are the most reactive. The effect of Fe-bearing minerals on the acid leaching of chalcopyrite, the most common primary Cu ore mineral was investigated by comparing mixtures of chalcopyrite with (i) chamosite, (ii) berthierine-chamosite, and (iii) pyrite. The lixiviant consisted of solutions with 0.1 m Fe2(SO4)3 + 0.3 m H2SO4, and the experiments were conducted in an orbital shaking water bath at 50°C for 43 days. The solution pH increased and Eh decreased for all systems, resulting in conditions that became less optimal for Cu recovery. Scanning electron microscope imaging highlighted the porous nature and variable elemental composition of the (partially) dissolved phyllosilicate minerals/amorphous-silica-residue after leaching. Micro X-ray Absorption Near Edge Structure (μXANES) measurements revealed that sulfur exists in multiple oxidation states both within the silicate gangue and around chalcopyrite, emphasising how the formation of an amorphous-silica-residue increased the complexity of the system. This complexity is related to the fact that (partial) dissolution of phyllosilicate gangue minerals during acid leaching results in the release of ions that change the solution chemistry; and form an amorphous-silica-residue, that contains numerous pores. These pores can act as local micro-reactors with non-equilibrium conditions and promote a heterogenous chemical composition. Subsequent mineral surface-fluid interactions in (partially) dissolved phyllosilicate/amorphous-silica-residue pores can vary, depending on the local chemical composition, making the leaching behaviour of chalcopyrite highly dependent on local conditions and on the mineralogical composition of the ores.
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Jul 2025
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Optics
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Open Access
Abstract: A study on the thermal load of cryogenically cooled silicon in synchrotron double-crystal monochromators is presented, based on experimental data from four different beamlines at Diamond Light Source. Different amounts of power are deposited on the first monochromator crystal by varying the storage ring current. The resulting crystal deformation causes a decline in the diffraction efficiency when power and power density are above threshold values. The results are compatible with an analytical model of thermo-mechanical deformation. Acceptable monochromator heat load values are determined with this model, to ensure optimal function of the monochromator. This model, previously tested against finite element analyses, is now validated against measured data and it will be used as a tool for initial analysis of monochromator performance on upgraded photon sources.
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Jul 2025
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I18-Microfocus Spectroscopy
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Sarah B.
Gosling
,
Emily L.
Arnold
,
Lois
Adams
,
Paul
Cool
,
Kalotina
Geraki
,
Mark O.
Kitchen
,
Iain D.
Lyburn
,
Keith D.
Rogers
,
Tim
Snow
,
Nick
Stone
,
Charlene E.
Greenwood
Diamond Proposal Number(s):
[31847]
Open Access
Abstract: Calcifications across the body offer snapshots of the surrounding ionic environment at the time of their formation. Links between prostate calcification chemistry and cancer are becoming of increasing interest, particularly in identifying biomarkers for disease. This study utilizes X-ray fluorescence mapping of 72 human prostate calcifications, measured at the I18 beamline at the Diamond Light Source, to determine the links between calcifications and their environment. This paper offers the first investigation of the elemental heterogeneity of prostate calcifications, demonstrating lower relative levels of minor elements at the calcification center compared to the edge but higher levels of zinc. Importantly, this study uniquely presents links between average Fe, Cr, Mn, Cu, and Ni ratios and grade Group (a classification system for urological tumors, specifically for prostate cancer), highlighting a potential avenue of exploration for biomarkers in prostate calcifications.
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Jul 2025
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I18-Microfocus Spectroscopy
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Sarah B.
Gosling
,
Emily L.
Arnold
,
Lois
Adams
,
Paul
Cool
,
Kalotina
Geraki
,
Mark O.
Kitchen
,
Iain D.
Lyburn
,
Keith D.
Rogers
,
Tim
Snow
,
Nick
Stone
,
Charlene E.
Greenwood
Diamond Proposal Number(s):
[31847]
Open Access
Abstract: Prostate cancer remains the most common male cancer; however, treatment regimens remain unclear in some cases due to a lack of agreement in current testing methods. Therefore, there is an increasing need to identify novel biomarkers to better counsel patients about their treatment options. Microcalcifications offer one such avenue of exploration. Microfocus spectroscopy at the i18 beamline at Diamond Light Source was utilised to measure X-ray diffraction and fluorescence maps of calcifications in 10 µm thick formalin fixed paraffin embedded prostate sections. Calcifications predominantly consisted of hydroxyapatite (HAP) and whitlockite (WH). Kendall’s Tau statistics showed weak correlations of ‘a’ and ‘c’ lattice parameters in HAP with GG (rτ = − 0.323, p = 3.43 × 10–4 and rτ = 0.227, p = 0.011 respectively), and a negative correlation of relative zinc levels in soft tissue (rτ = − 0.240, p = 0.022) with GG. Negative correlations of the HAP ‘a’ axis (rτ = − 0.284, p = 2.17 × 10–3) and WH ‘c’ axis (rτ = − 0.543, p = 2.83 × 10–4) with pathological stage were also demonstrated. Prostate calcification chemistry has been revealed for the first time to correlate with clinical markers, highlighting the potential of calcifications as biomarkers of prostate cancer.
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Apr 2025
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I18-Microfocus Spectroscopy
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Diamond Proposal Number(s):
[31591, 35606]
Open Access
Abstract: Despite being pivotal to the habitability of our planet, the process by which Earth gained its present-day hydrogen budget is unclear. Due to their isotopic similarity to terrestrial rocks across a range of elements, the meteorite group that is thought to best represent Earth's building blocks is the enstatite chondrites (ECs). Because of ECs' nominally anhydrous mineralogy, these building blocks have long been presumed to have supplied negligible hydrogen to the proto-Earth. However, recent bulk compositional measurements suggest that ECs may unexpectedly contain enough hydrogen to readily explain Earth's present-day water abundance. Together, these contradictory findings mean the contribution of ECs to Earth's hydrogen budget is currently unclear. As such, it is uncertain whether appreciable hydrogen is a systematic outcome of Earth's formation. Here, we explore the amount of hydrogen in ECs as well as the phase that may carry this element using sulfur X-ray absorption near edge structure (S-XANES) spectroscopy. We find that hydrogen bonded to sulfur is prevalent throughout the meteorite, with fine matrix containing on average almost 10 times more Hsingle bondS than chondrule mesostasis. Moreover, the concentration of the Hsingle bondS bond is linked to the abundance of micrometre-scale pyrrhotite (Fe1-xS, 0 < x < 0.125). This sulfide can sacrificially catalyse a reaction with H2 from the disk at high temperatures to create H2S, which could be dissolved in adjoining molten silicate-rich material. Upon rapid cooling, this assemblage would form pyrrhotite encased in submicron silicate-rich glass that carries trapped H2S. These findings indicate that hydrogen is present in ECs in higher concentrations than previously considered and could suggest that this element may have a systematic, rather than stochastic, origin on our planet.
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Apr 2025
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I18-Microfocus Spectroscopy
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Thomas
Barthelay
,
Robert
Gray
,
Howard
Richards
,
Paloma
Rodriguez Santana
,
Sylvia
Britto
,
Kalotina
Geraki
,
Zhenyuan
Xia
,
Johanna
Xu
,
Leif E.
Asp
,
Chris
Bowen
,
Frank
Marken
,
Alexander
Lunt
,
Andrew
Rhead
Diamond Proposal Number(s):
[30127]
Open Access
Abstract: Structural batteries utilise the bifunctionality of carbon fibres to act as a load-bearing structure, but also as a conductive current collector for a battery electrode. Lithium-ion transport during the cycling of structural battery cathodes coated with different morphologies is investigated using Iron X-Ray Absorption Near Edge Spectroscopy (Fe XANES) and correlated to electrochemical performance. Two contrasting morphologies were produced using slurry coating and electrophoretic deposition (EPD) of lithium-iron phosphate (LFP) onto continuous carbon fibres. The ability to study the different structural battery cathode morphologies operando allows for a comparative analysis of their impact on cycling performance. The EPD-coated fibres exhibited a more homogeneous, thinner coating around the fibre compared to the thick, one-sided coating produced using slurry coating. Despite a lower initial capacity and 30 % lithium re-intercalation loss in the first cycle, EPD-coated fibres exhibited more stable capacity retention over time compared to slurry-coated counterparts. Electrochemical Impedance Spectroscopy (EIS) revealed initially high ionic resistance for the EPD-coated fibres, but a larger increase in resistance in the slurry coated electrodes over multiple cycles. This study demonstrated an innovative and novel method of analysing in greater detail, the cycling ability of the coated cathode material on carbon fibres using synchrotron radiation.
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Feb 2025
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I18-Microfocus Spectroscopy
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Veronica
Clavijo Jordan
,
André F.
Martins
,
Erica
Dao
,
Kalotina
Geraki
,
Sara
Chirayil
,
Xiaodong
Wen
,
Pooyan
Khalighinejad
,
Daniel
Parrott
,
Xiaojing
Wang
,
Patricia
Gonzalez Pagan
,
Neil
Rofsky
,
Michael
Farquharson
,
A. Dean
Sherry
Open Access
Abstract: Previous studies have shown that the zinc-responsive MRI probe, GdL1, can distinguish healthy versus malignant prostate tissues based upon differences in zinc content and secretion. In this study, mice were fed chow containing low, normal, or high zinc content for 3 weeks before imaging glucose stimulated zinc secretion (GSZS) by MRI. The distribution of zinc in prostate tissue in these three groups was imaged by synchrotron radiation X-ray fluorescence (SR-XRF). A zinc deficiency caused systemic and organ-level dysregulation, weight loss, and altered zinc bioavailability. Zinc efflux from the prostate increased in parallel to dietary zinc in healthy mice but not in TRAMP mice, consistent with a lowered capacity to store dietary zinc in malignant cells. This differential zinc efflux suggests that a dietary supplement of zinc prior to a GSZS study may enhance image contrast between healthy and malignant prostate tissue, thereby improving the accuracy of prostate cancer detection in man.
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Nov 2024
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I18-Microfocus Spectroscopy
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Diamond Proposal Number(s):
[23705]
Abstract: Prostate cancer (PCa) is the most diagnosed cancer in Canadian men, accounting for 20% of all new cancer cases in 2023[1]. With such high incidence, it is important that diagnostic tools advance for adequate treatment of the disease. Contrast agents (CA) are administered in magnetic resonance imaging (MRI) clinical exams to enhance image contrast between adjacent structures and tissues. The efficacy of a CA is determined by the distribution and concentration of the agent throughout organs of interest and in the extracellular space of all tissues.
Micro-synchrotron radiation x-ray fluorescence (μ-SRXRF) is a non-destructive measurement technique that uses a tunable photon beam focused to the micron scale. In this work, μ-SRXRF was used to examine and characterize the co-localization of a gadolinium-based zinc-sensitive agent (GdL2) currently under development for detection of PCa by MRI. Prostate tissue samples were collected from control mice and transgenic adenocarcinoma of the mouse prostate (TRAMP) mice, an established prostate cancer model [2], after an MRI exam that included injection of GdL2. The samples were raster scanned to investigate trends in Gd, from the CA, and Zn, a biomarker for PCa diagnoses. Elements such as Cu, Fe, S, P, and Ca were also investigated.
Significant Zn and Gd co-localization was observed in both healthy and malignant mouse tissues. In addition, a marked decrease in Zn was found in the lateral lobe of the prostate obtained from mice with PCa. We demonstrate here that μ-SRXRF is a useful tool for monitoring the distribution of several elements including Zn and Gd in animal models of cancer. The optimized procedures for tissue preparation, processing, data collection, and analysis will be described.
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Sep 2024
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I18-Microfocus Spectroscopy
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Diamond Proposal Number(s):
[30196]
Open Access
Abstract: Heterotopic ossification (HO) in tendons can lead to increased pain and poor tendon function. Although it is believed to share some characteristics with bone, the structural and elemental compositions of HO deposits have not been fully elucidated. This study utilizes a multimodal and multiscale approach for structural and elemental characterization of HO deposits in healing rat Achilles tendons at 3, 6, 12, 16, and 20 weeks post transection. The microscale tomography and scanning electron microscopy results indicate increased mineral density and Ca/P ratio in the maturing HO deposits (12 and 20 weeks), when compared to the early time points (3 weeks). Visually, the mature HO deposits present microstructures similar to calcaneal bone. Through synchrotron-based X-ray scattering and fluorescence, the hydroxyapatite (HA) crystallites are shorter along the c-axis and become larger in the ab-plane with increasing healing time, while the HA crystal thickness remains within the reference values for bone. At the mineralization boundary, the overlap between high levels of calcium and prominent crystallite formation was outlined by the presence of zinc and iron. In the mature HO deposits, the calcium content was highest, and zinc was more present internally, which could be indicative of HO deposit remodeling. This study emphasizes the structural and elemental similarities between the calcaneal bone and HO deposits.
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Jul 2024
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I18-Microfocus Spectroscopy
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Diamond Proposal Number(s):
[19447, 22661]
Open Access
Abstract: Iron dyshomeostasis and neuroinflammation, characteristic features of the aged brain, and exacerbated in neurodegenerative disease, may induce oxidative stress-mediated neurodegeneration. In this study, the effects of potential priming with mild systemic iron injections on subsequent lipopolysaccharide (LPS)-induced inflammation in adult C57Bl/6J mice were examined. After cognitive testing, regional brain tissues were dissected for iron (metal) measurements by total reflection X-ray fluorescence and synchrotron radiation X-Ray fluorescence-based elemental mapping; and iron regulatory, ferroptosis-related, and glia-specific protein analysis, and lipid peroxidation by western blotting. Microglial morphology and astrogliosis were assessed by immunohistochemistry. Iron only treatment enhanced cognitive performance on the novel object location task compared with iron priming and subsequent LPS-induced inflammation. LPS-induced inflammation, with or without iron treatment, attenuated hippocampal heme oxygenase-1 and augmented 4-hydroxynonenal levels. Conversely, in the cortex, elevated ferritin light chain and xCT (light chain of System Xc−) were observed in response to LPS-induced inflammation, without and with iron-priming. Increased microglial branch/process lengths and astrocyte immunoreactivity were also increased by combined iron and LPS in both the hippocampus and cortex. Here, we demonstrate iron priming and subsequent LPS-induced inflammation led to iron dyshomeostasis, compromised antioxidant function, increased lipid peroxidation and altered neuroinflammatory state in a brain region-dependent manner.
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May 2024
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