B18-Core EXAFS
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Diamond Proposal Number(s):
[33047]
Open Access
Abstract: Human skeletal samples burned between 200 and 1000 °C, in both aerobic and anaerobic conditions, were probed by synchrotron-based Extended X-ray Absorption Fine Structure with a view to interpret heat-induced variations in chemical composition and structure. Heat-prompted changes in Ca2+ first and second coordination shells were unveiled (regarding PO43−, CO32− and/or OH− ligands). A higher crystallinity degree was found for 800-1000 °C burning temperatures as compared to 200-700 °C, in agreement with the higher amount of organic components in moderately heated samples. The unique local structural information delivered by XAS, particularly on the Ca2+ coordination environment which determines bone's structural features and degree of crystallinity, enabled an improved understanding of the heat-elicited changes undergone by bone, not previously accessed by other techniques. This is an innovative study, with a high impact in forensic and bioarchaeological research, focused on the analysis of burned human skeletal remains.
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Oct 2026
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I04-Macromolecular Crystallography
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Stéphane
Bourg
,
Matthieu
Place
,
Chloé
Copin
,
Apirat
Chaikuad
,
Thomas
Robert
,
Hanna
Holzmann
,
Susanne
Müller
,
Stéphane
Bach
,
Sandrine
Ruchaud
,
Stefan
Knapp
,
Frédéric
Buron
,
Sylvain
Routier
,
Pascal
Bonnet
Abstract: CLK1 is one of the four human isoforms of the cdc2-like (CLK) kinases that has been suggested as a therapeutic target in diverse diseases based on its important role regulating mRNA splicing. For example, CLKs and closely related kinases such as DYRK1A have been targeted in Alzheimer’s disease and other diseases in which splice site selection contributes to the disease development. Here we have developed an efficient in silico fragment-based ligand design approach to identify novel CLK1 inhibitors with excellent ligand efficiency based on an imidazo[2,1-b][1,3,4]thiadiazole fragment. More than one million docking poses were generated from 26,225 unique virtual compounds, and after applying several filtering steps, 11 compounds were selected, synthesized and their CLK1 inhibition and cellular potency were evaluated. Gratifyingly, inhibitor potencies were in excellent agreement with predicted values and crystallographic data of an inhibitor bound to CLK1 confirmed the unusual binding mode of the compounds.
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Oct 2026
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B18-Core EXAFS
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Abstract: Dual-atom catalysts (DACs) surpass the limitations of single-atom catalysts by harnessing synergy between adjacent metal sites. Herein, we propose a novel strategy employing d-p orbital synergistic modulation in Fe-Sb DACs. Combined density functional theory and molecular dynamics simulations reveal that the significant d-p orbital synergistic regulation between Fe and Sb sites promotes O2 adsorption and activation, lowers the energy barrier for Osingle bondO bond cleavage, and optimizes water desorption. As a proof-of-concept, Fe/Sb DACs anchored on a nitrogen-doped carbon matrix (Fe/Sb-N-C) were synthesized. The atomic-level local coordination of Fe-Sb dual atoms was systematically characterized by aberration-corrected high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) and X-ray absorption fine structure (XAFS) analyses. The as-fabricated Fe/Sb-N-C exhibits exceptional alkaline oxygen reduction reaction (ORR) performance, featuring a half-wave potential of 0.92 V and outstanding durability. Aqueous Zn-air batteries equipped with Fe/Sb-N-C achieve a high maximum power density of 196 mW cm-2 and a specific capacity of 795 mAh g-1. Furthermore, quasi-solid-state Zn-air batteries demonstrate wide-temperature operability (-30 to 60 °C) and stability under high current densities. This work establishes d-p orbital synergy as a new paradigm for designing high-efficiency ORR catalysts, broadening their application in energy devices across extreme temperatures.
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Sep 2026
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B21-High Throughput SAXS
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Giuseppe Junior
Mosca
,
Simone
Russo
,
Valentina
Pelliccioli
,
Martina
Quaglia
,
Pietro
Pettinari
,
Alessandro
Cangiano
,
Diego
Colombo
,
Paola
Perego
,
Giovanni L.
Beretta
,
Laura
Morelli
,
Giuseppe
Vitiello
Diamond Proposal Number(s):
[34244]
Abstract: Colloidal quantum dots (QDs) represent a versatile class of luminescent nanomaterials whose physicochemical and interfacial properties can be engineered for advanced bio-related applications. Herein, the wet-precipitation synthesis and surface engineering of ultra-small fluorine-doped ZnO quantum dots (F/ZnO QDs) were proposed and their formulation into stable amphiphilic nanosystems using synthetic glycoglycerolipids. To control aggregation and interfacial behavior, the QDs were first capped with oleylamine and subsequently functionalized through an emulsion-based approach with mono-acyl or di-acyl glycoglycerolipids, yielding double-coated amphiphilic nanoformulations. The resulting materials were extensively characterized by TEM, DLS, zeta-potential measurements, XRD, FTIR/ATR, UV–Vis, and fluorescence spectroscopy, allowing to explore correlations between surface chemistry, colloidal stability, and optical properties. Glycoglycerolipid functionalization led to a marked improvement in aqueous dispersibility and long-term colloidal stability while preserving the enhanced fluorescence induced by fluorine doping. Biological assays confirmed the cytocompatibility of the coated QDs and supported their suitability for further biointerface studies. This work highlights glycoglycerolipid-based amphiphilic coatings as an effective strategy to tailor the surface and colloidal properties of ZnO-based QDs, enabling the development of stable luminescent nanomaterials as biocompatible nanoprobes and for bio-interfacial applications.
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Aug 2026
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I04-Macromolecular Crystallography
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Diamond Proposal Number(s):
[28402, 35088]
Open Access
Abstract: Keratin is an abundant structural fibrous protein and extremely recalcitrant biopolymer. β-Keratin is the major constituent of feathers, which, due to the widespread poultry industry, has become a major waste product. Biotechnological upcycling of feather waste has gained interest as various bacteria and fungi capable of degrading keratin have been isolated. These microorganisms produce proteases, termed keratinases, responsible for the enzymatic hydrolysis of keratin. The structural properties that confer keratinolytic activity to proteases are, however, not well understood. Here, we investigated the structure-function relationship of a subtilisin-like S8 endopeptidase (FerB) from the thermophile Fervidobacterium pennivorans strain T. FerB was crystallized and its structure solved to 1.5 Å resolution, revealing an auto-processed state where the pro-peptide domain is non-covalently attached to the catalytic domain. The carboxyl group of the scissile peptide bond is coordinated in the active site within hydrogen bonding distance of the catalytic triad’s serine residue. Unlike fervidolysin, no β-sandwich domains are present. However, a tyrosine-rich β-hairpin structure is found in the corresponding position within the FerB structure. Deletion of the β-hairpin reduced the protein’s integrity and keratinase activity.
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Aug 2026
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I15-Extreme Conditions
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Diamond Proposal Number(s):
[7758, 8615]
Open Access
Abstract: The β′-Gd2(MoO4)3 phase is one of the most well-known multiferroic materials, exhibiting both ferroelectricity and ferroelasticity under ambient conditions, with a complex temperature-pressure phase diagram. In this study, we review the pressure-dependent behavior of the RE2(MoO4)3 compound family (where RE ≡ Pr–Ho), which crystallizes in the β′-phase, with the β-phase being the paraelectric parent structure. Eu, Tb, and Ho molybdates were synthesized via solid-state reactions, ensuring the absence of impurities. High-pressure experiments at DIAMOND synchrotron revealed that the β′-phase persists at low-pressures. At approximately 2 GPa, new peaks emerged, which were refined as a mixture of the β′-phase, other rare-earth molybdates, and oxides, some of which have been detected in earlier stages of synthesis. The β′-phase became distorted with increasing pressure while coexisting with these new phases, whose average unit cell volume was found to lie between that of the β′-phase and the formed distorted phase. Ultimately, this multiphase crystalline decomposition acts as a precursor to pressure-induced amorphization, leading to a loss of long-range periodicity without complete loss of local order. The onsets of pressure-induced decomposition, distortion of the β′-phase and apparent amorphization increase as the ionic radius of the rare-earth element decreases. This scenario of irreversible structural disorder accumulated through phase coexistence is consistent with previous studies and resolves a debate persisting for over half a century.
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Aug 2026
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B07-B1-Versatile Soft X-ray beamline: High Throughput ES1
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Diamond Proposal Number(s):
[43895]
Open Access
Abstract: X-ray photoelectron spectroscopy (XPS) is a major technique in catalyst research due to its ability to determine chemical states on the surface. Near ambient pressure XPS (NAP-XPS) enables in situ analysis, offering valuable insight into catalytic processes. However, modern catalysts are often supported on non-conductive supports such as TiO2 or SiO2, which can present significant challenges for XPS analysis due to charging and differential charging. These issues can distort spectral data, rendering data unusable and wasting valuable instrument time. While several sample preparation strategies exist, many are limited by not allowing high temperature analysis, the risk of sample loss (e.g., from powder flaking off), or continued susceptibility to charging. In this work, we introduce a simple, robust, and time-efficient method for mounting catalyst powders by compressing them between aluminium foil disks. This approach provides excellent sample hold, minimises charging effects, and is suitable for high-temperature NAP-XPS analysis and synchrotron x-ray sources. The method addresses key limitations of conventional preparation techniques and enables more reliable characterisation of insulating catalyst materials.
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Aug 2026
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Electrical Engineering
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Abstract: A robust single-phase AC–AC chopper topology with a grounded load is proposed for compact, high-efficiency power conversion. The converter comprises one P-type and one N-type AC switching-cell leg, enabling four-quadrant operation while simultaneously being inherently immune to shoot-through conditions. The legs are connected to a grounded load via a coupled inductor, and together with a three-step switching strategy, form a topology that is tolerant to supply voltage polarity detection errors of at least ±20° around the mains zero-crossing, without the need for large, bulky snubbers. An analytic method is presented for sizing the current-limiting inductors, which accounts for the effects of circuit parasitics. SPICE simulations and measurements from a 1.5 kW GaN-based prototype validate the design, demonstrating low output voltage total harmonic distortion and high robustness. The converter is suitable for space-constrained, high-performance AC–AC conversion applications.
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Jul 2026
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I24-Microfocus Macromolecular Crystallography
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Jos J. A. G.
Kamps
,
Philip
Hinchliffe
,
Johan
Glerup
,
Emily I.
Freeman
,
Pauline A.
Lang
,
Catherine
Tooke
,
Michael
Beer
,
Laura
Parkinson
,
Do-Heon
Gu
,
Sehan
Park
,
Nicholas
Devenish
,
Tiankun
Zhou
,
Anastasya
Shilova
,
Samanpreet
Kaur
,
Patrick
Rabe
,
Christopher J.
Schofield
,
James
Spencer
,
Jaehyun
Park
,
Robin L.
Owen
,
Allen M.
Orville
,
Pierre
Aller
Diamond Proposal Number(s):
[25260]
Open Access
Abstract: We describe the design and implementation of a drop-on-fixed-target method for time-resolved serial crystallography at both synchrotron and XFEL facilities. A piezoelectric droplet dispensing pipette is employed for addition of picolitre volume aqueous droplets (∼40–90 pl; ∼40–55 µm diameter sphere), containing (co-)substrate(s) or ligand(s), onto enzyme microcrystals previously loaded into the trapezoidal wells of an etched crystalline silicon fixed-target chip containing 25 600 wells in a high-density, square grid with 125 µm centre-to-centre well spacing. These features demand exquisite accuracy and thereby constrain motion controls to enable robust time-resolved crystallographic studies. The system was tested with three enzyme systems, comprising lysozyme and two β-lactamases, CTX-M-15 and AmpCEC. Mitigation strategies for cross-well contamination, including the implementation of interleaved controls, are described; the overall performance of the system at synchrotron and X-ray free-electron laser facilities was evaluated. This drop-on-fixed-target method is a reliable framework for time-resolved crystallography and will improve the consistency of measurements across facilities.
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Jul 2026
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I15-Extreme Conditions
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Diamond Proposal Number(s):
[37838]
Open Access
Abstract: The structural behaviour of homoleptic xenon difluoride (XeF2) complexes [M(XeF2)6][SbF6]2 (M = Cu, Zn) under varying temperature and pressure has been investigated, aiming to resolve the disordered Jahn–Teller distortions in the copper complex (CuSb). At 200 K, both CuSb and its zinc analogue (ZnSb) crystallize in a layered CdCl2-type structure with the space group R3. Upon cooling below 170 (CuSb) and 160 K (ZnSb), both systems transition to isostructural phases in P1, with CuSb assuming an ordered Jahn–Teller distortion. The transformation is driven by the shortening and optimization of the Xe⋯F intermolecular contacts, forming stronger and more directional interactions, rather than by Jahn–Teller effects alone. This is supported by the observation of similar transitions in the Jahn–Teller-inactive Zn system. High-pressure experiments up to ∼2.8 GPa at room temperature show the structural stability of the high-symmetry phases, implicating kinetic barriers to further transformation. Additionally, the synthesis and structural characterization of a novel arsenic analogue, [Zn(XeF2)6][AsF6]2 (ZnAs), reveal similar layered motifs but distinct phase behaviour. Symmetry-mode analyses relate all observed phases through distortions of a common CdCl2 aristotype.
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Jul 2026
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