Brazilian Synchrotron Light Laboratory

Multi-technique high resolution X-ray mapping enhanced by the recent advent of 4th generation synchrotron facilities can produce colossal datasets, challenging traditional analysis methods. Such difficulty is clearly materialized when probing the crystal structure of inhomogeneous samples, where the number of diffraction patterns quickly increases with map resolution, making the identification of crystal phases within a vast collection of reflections unfeasibly challenging by direct human inspection. Here we develop an analysis approach based on a physics-informed similarity measure and unsupervised clustering algorithms for identifying independent phases within a diffraction spatial map, which allowed us to identify the material distribution across a high-pressure cerium hydride. By investigating the specific compound, we also contribute to the understanding of synthesis inhomogeneities among the superhydrides, a prominent superconductor class in condensed matter physics whose characterization is highly challenging even for state-of-the-art materials techniques. The analysis framework we present may be readily extended to any correlated set of curves whose features are tied to specific entities such as structural phases.

The clinical success of an implant largely depends on its ability to promote bone repair and facilitate osteointegration. While significant advancements have been made in designing new scaffolds, a thorough evaluation of implant success at various bone length scales has not been sufficiently investigated. Bone is a hierarchically organized tissue, with an intricate structure that ranges from the organization of collagen fibrils and their mineralization at the nanometer and micrometer scales to the macroscopic arrangement of compact and cancellous bone. This hierarchical organization is crucial for ensuring bone function and mechanical performance. In this context, a comprehensive assessment of the effects of biomaterials on bone repair at multiple length scales is essential for evaluating the effectiveness and safety of implanted materials. However, preparing samples for integrated multimodal analyses poses a technical challenge. In this work, we present a protocol designed to evaluate bone regeneration across various hierarchical levels and analyze the interface between newly formed bone and the implanted scaffold. This approach provides a robust method for assessing the effectiveness of scaffolds in inducing bone repair. The combination of selected 3D and 2D imaging techniques is crucial for a proper evaluation of the complex mineralized tissue that forms during the bone healing process.

Transformation of agro-industrial products into value-added products, such as prebiotic oligosaccharides, is a key element of the emerging bioeconomy. Here, we characterized a new GH30_8 glucuronoxylanase from Bacillus pumilus (BpXyn30_8A) for its potential in producing xylooligosaccharides (XOS). BpXyn30_8A showed tolerance to ethanol and NaCl and released both linear and branched XOS containing MeGlcA at the penultimate nonreducing end residue. Its X-ray structure, determined at 2.16 Å resolution, revealed high similarity to other glucuronoxylanases. Furthermore, BpXyn30_8A achieved higher xylan conversion yields from corn cob and Eucalyptus sawdust than Ruminococcus champanellensisRcXyn30A. Finally, fermentation assays showed that Bifidobacterium adolescentis metabolized neutral XOS to acetate and lactate, whereas acidic XOS were poorly utilized. These results highlight the potential of BpXyn30_8A as a valuable enzyme for the green transformation of plant biomass into prebiotic oligosaccharides with promising applications in human and animal nutrition, health, and biotechnology.

Hybrid pixel detectors are photon-counting devices for X-ray imaging and diffraction techniques at the fourth-generation Sirius synchrotron light source (LNLS/CNPEM). This work presents a comprehensive characterization regarding Modulation Transfer Function and pixel count rate linearity under high-flux conditions of the large-area PIMEGA detectors of 300 and 675 μm thick silicon sensors. They consist of photon-counting devices with a 55 microns pixel size based on Medipix3RX ASIC. The results validate the successful construction and performance of the Medipix3RX-based PIMEGA detectors. The silicon sensor platform offers a viable compromise between absorption efficiency and spatial resolution, making it a highly attractive technological solution for imaging and diffraction applications across the tender to initial hard X-ray energy ranges.

Abstract The discovery of new mineral phases capable of transporting water into the Earth’s mantle via subduction zones is essential for understanding the deep Earth water cycle and its influence on mantle dynamics. Recent experimental and computational studies have proposed that certain hydrated oxyhydroxides may remain stable under lower mantle conditions, particularly within cold subducting slabs. Here, we report on an advanced synchrotron multi-technique study on a natural complex iron oxyhydroxide mineral preserved within a super-deep diamond. This finding provides direct evidence that specific hydrous minerals survive at approximately ~ 900 to 1,250 km depths at the lower mantle. Moreover, it offers new evidence on water transport via cold subducted slabs and highlights the potential role of iron oxyhydroxides as carriers of volatiles into Earth’s deep interior.