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Filamentous fungi produce a wide range of relevant biotechnological compounds. The close relationship between fungal morphology and productivity has led to a variety of analytical methods to quantify their macromorphology. Nevertheless, only a µ‐computed tomography (µ‐CT) based method allows a detailed analysis of the 3D micromorphology of fungal pellets. However, the low sample throughput of a laboratory µ‐CT limits the tracking of the micromorphological evolution of a statistically representative number of submerged cultivated fungal pellets over time. To meet this challenge, we applied synchrotron radiation‐based X‐ray microtomography at the Deutsches Elektronen‐Synchrotron [German Electron Synchrotron Research Center], resulting in 19,940 3D analyzed individual fungal pellets that were obtained from 26 sampling points during a 48 h Aspergillus niger submerged batch cultivation. For each of the pellets, we were able to determine micromorphological properties such as number and density of spores, tips, branching points, and hyphae. The computed data allowed us to monitor the growth of submerged cultivated fungal pellets in highly resolved 3D for the first time. The generated morphological database from synchrotron measurements can be used to understand, describe, and model the growth of filamentous fungal cultivations. [ABSTRACT FROM AUTHOR]

Increasing evidence indicates that microscale heterogeneity is critical to interpret and predict macroscopic soil processes and functions. However, the difficulty of measuring soil characteristics, such as soil organic carbon (SOC) and microbial biomass, at the micron level greatly hinders our understanding of how microscale soil heterogeneity quantitatively regulates macroscopic soil behaviors. Here, we investigated the effect of microscale distributions of soil water saturation (S), SOC content (CSOC), and microbial biomass (CMB) on soil heterotrophic respiration (SHR) using a microscale process-based model. The microscale distributions of S, CSOC, and CMB were mathematically determined by assuming they varied linearly with local soil porosity, which was derived from X-ray computed tomography, and the effect of microscale heterogeneity on SHR rates was examined under different water saturations and carbon availabilities. The results show that microscale soil heterogeneity stimulated macroscopic SHR only when it alleviated resource limits or environmental stress. For instance, the heterogeneous S improved the SHR rate by reducing microbial water stress or enhancing dissolved organic carbon (DOC) diffusion, whereas the heterogeneous CSOC enhanced CO2 flux by increasing DOC availability. In addition, the heterogeneous CMB promoted CO2 flux by increasing microbial accessibility of substrates. The interactions among water, SOC, and microbes at the micron scale may stimulate or restrict CO2 emission, depending on soil water saturation and DOC availability. Given the nature of soil heterogeneity at the micron scale and the challenge of measuring microscale soil characteristics, this study provided invaluable insights into how microscale heterogeneity regulates macroscale soil behaviors. [ABSTRACT FROM AUTHOR]

Cover crops (CC) could improve soil physical, chemical, and biological properties; however, the micrometer scale quantification of geometric pore characteristics in CC soil is limited in the literature. The objective of this study was to differentiate geometrical pore characteristics between CC and no CC (NCC) by computed tomography (CT). The study design consisted of winter CC and summer corn (Zea mays L.)–soybean [Glycine max (L.) Merr.] rotation with no‐till management. The sample cores were collected after 7 yr of mixed species CC establishment. Six 0‐to‐65‐mm‐long soil cores (28‐mm diam.) were imaged at 29‐μm resolution, and three‐dimensional volumes were analyzed using Fiji‐ImageJ2 software. Slice thickness was 29 μm, and the minimum achievable voxel size was 90 nm. Images within the top and bottom 7.25 mm were removed, and two depths within a core were analyzed for soil pore parameters. The total pore volume was significantly greater (P <.05) in CC compared with NCC, with 8.4 and 2.5 times greater values in CC at 7.25–27.25 and 37.25–57.25 mm, respectively. The total (individual + branched) and the individual pore count were significantly greater (P <.05) in CC compared with NCC for both depths. The porosity of CC soil at 7.25‐to‐27.25‐mm depth was 10 times greater than that of NCC. The branched pore count was not significantly different between two treatments. Overall, the micrometer scale determination of geometrical pore network characteristics showed added benefits of CC use compared with NCC; thus, the use of CC can be beneficial in improving soil pore networks. Core Ideas: Cover crops improve soil pore volume measured by micro‐computed tomography (μCT).Cover crops improve soil physical characteristics.μCT‐measured imageJ analysis is a good method for soil geometrical pore characteristic identification. [ABSTRACT FROM AUTHOR]

Large deformations under in-plane compression of paperboard appear in forming processes like hydroforming, pressforming and deep drawing, but the mechanisms of deformation have not been studied on a micromechanical level. A constrained in-plane compression test is presented. This test allows for in-plane compression, buckling, wrinkling and compaction. The constrained compression test is realized using a DEBEN CT-500 in-situ tester for laboratory microtomography and synchrotron microtomography. Experiments with five different materials spanning from laboratory handsheets to commercially available multi-layered paperboards are performed. Image processing is used to observe the local out-of-plane fiber orientation and compaction. A phenomenological investigation of the deformation behavior of these materials is presented. Delamination is found to be the primary mechanisms of failure in the multi-layered boards. Furthermore, a porous network structure, created by using long and minimally refined softwood fibers, is found to facilitate the formation of uniform wrinkles and compaction. [ABSTRACT FROM AUTHOR]

Environmentally induced cracking (EIC) in a sensitized high-strength AA5083 H131 alloy has been investigated using time-lapse synchrotron X-ray computed tomography combined with post-mortem correlative characterization. Small corrosion features deliberately introduced in a pre-exposure step were found to be the site of initiation for over 95% of the 44 EIC cracks that developed under slow strain rate testing. Detailed analysis using three-dimensional electron backscatter diffraction and energy-dispersive spectroscopy analysis of a single crack confirmed the intergranular nature of the cracks from the start and that the pre-exposure corrosion was associated with an α-AlFeMnSi particle cluster. It also appears that several cracks may have initiated at this site, which later coalesced to form the 300-μm-long crack that ultimately developed. Of further note is the fact that initiation of the EIC cracks across the sample started below the yield strength and continued beyond the ultimate tensile strength. The most rapid crack propagation occurred during sample extension following a period of fixed displacement. [ABSTRACT FROM AUTHOR]

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Taxonomic work on soft-bodied and gelatinous cnidarians is a challenging task because preservation often causes difficulties for storage and identification of the specimens. Moreover, examination of scyphozoan and cubozoan statoliths, which can probably provide information on systematics and the age of medusae, are difficult since the crystals dissolve when exposed to air or aqueous solutions. In order to overcome such limitations, we evaluated the benefits of a non-invasive approach using X-ray micro-computed tomography (micro-CT). Various cnidarian taxa (Scyphozoa, Cubozoa, Hydrozoa, Staurozoa) were investigated with particular focus on scyphozoan and cubozoan statoliths. We further evaluated the effect of different fixatives (e.g. ethanol, glutaraldehyde, Trumps) and contrast-enhancing agents (iodine or osmium tetroxide). The reconstruction of tomographic data revealed that osmium tetroxide staining significantly enhanced the contrast of diagnostic morphological features of soft tissues whereas iodine staining was less effective. The reconstruction of scyphozoan and cubozoan statocysts allowed statolith analyses in their natural arrangement as well as automated morphometric measurements in three dimensions. In conclusion, micro-CT allows a detailed reconstruction of taxonomically important characters of soft-tissues and provides a sophisticated tool for reconstructing the spatial arrangement of complex internal structures expanding the opportunities for future research on marine organisms. [ABSTRACT FROM AUTHOR]

The study of below-ground features of roots and soil and their interactions is essential for understanding the configuration and diversities in such a dynamic environment. X-ray computed tomography is recognized as a tool for visualizing the physical interactions in the soil. In many studies, it has been used as a stand-alone tool to describe soil and root parameters. However, in recent times, attempts to couple it with other complementary tools are gaining rapid interest among researchers. The paper therefore provides an overview of the major application of combining X-ray computed tomography with other relevant methods in analyzing the structural characteristics of roots and soil media. The relevance of using this multidisciplinary approach for unraveling the mysteries surrounding root–soil dynamic interactions is stressed. The current and future trends of such studies are also pointed out. [ABSTRACT FROM AUTHOR]

Recent progress in the understanding of soil microbial processes at micrometric scales has created a need for models that accurately predict the microscale distribution of water, and the location of air–water interfaces in pores. Various models have been developed and used for these purposes, but how well they fare against real data has yet largely to be determined. In this context, for the first time, this article compares the prediction of two of these models to experimental data obtained on soil material. The distribution of water and air in soil samples constituted of repacked aggregates, equilibrated at three matric potentials ( − 0.5 kPa, − 1 kPa and − 2 kPa), was measured via synchrotron X-ray computed tomography at a resolution of 4.6 µ m. Water distribution was simulated by a two-phase lattice Boltzmann model (LBM) and a morphological model (MOSAIC). Results indicate that, when one lifts the assumption, motivated by capillary theory, that a pore can drain only if a connecting pore is already full of air, MOSAIC gives an acceptable approximation of the observed air–water interfaces. However, discretization of pores as geometrical primitives causes interfaces predicted by MOSAIC to have nonphysical shapes. By contrast, LBM is able to predict remarkably well the location of air–water interfaces. Nevertheless, given the huge difference in computing time (minutes versus tens of hours) required to run these two models, it is recommended that further research be carried out on the development of both, in parallel. [ABSTRACT FROM AUTHOR]

X-ray computed tomography (CT) is an invaluable technique for generating three-dimensional (3D) images of inert or living specimens. X-ray CT is used in many scientific, industrial, and societal fields. Compared to conventional 2D X-ray imaging, CT requires longer acquisition times because up to several thousand projections are required for reconstructing a single high-resolution 3D volume. Plenoptic imaging—an emerging technology in visible light field photography—highlights the potential of capturing quasi-3D information with a single exposure. Here, we show the first demonstration of a flexible plenoptic microscope operating with hard X-rays; it is used to computationally reconstruct images at different depths along the optical axis. The experimental results are consistent with the expected axial refocusing, precision, and spatial resolution. Thus, this proof-of-concept experiment opens the horizons to quasi-3D X-ray imaging, without sample rotation, with spatial resolution of a few hundred nanometres. [ABSTRACT FROM AUTHOR]

Simple Summary: This study aims at using a multi-technique approach to detect and analyze the effects of high dose rate spatially fractionated radiation therapies and to compare them to seamless broad beam irradiation targeting healthy and glioblastoma-bearing rat brains and delivering three different doses per each irradiation geometry. Brains were analyzed post mortem by multi-scale X-ray phase contrast imaging–computed tomography, histology, immunohistochemistry, X-ray fluorescence, and small- and wide-angle X-ray scattering to achieve detailed visualization, characterization and classification in 3D of the radio-induced effects on brain tissues. The original results bring new insights to the understanding of the response of cerebral tissue and tumors treated with high dose rate spatially fractioned radiotherapies and put the basis for channeling studies of in-vivo applications for monitoring RT effects. The purpose of this study is to use a multi-technique approach to detect the effects of spatially fractionated X-ray Microbeam (MRT) and Minibeam Radiation Therapy (MB) and to compare them to seamless Broad Beam (BB) irradiation. Healthy- and Glioblastoma (GBM)-bearing male Fischer rats were irradiated in-vivo on the right brain hemisphere with MRT, MB and BB delivering three different doses for each irradiation geometry. Brains were analyzed post mortem by multi-scale X-ray Phase Contrast Imaging–Computed Tomography (XPCI-CT), histology, immunohistochemistry, X-ray Fluorescence (XRF), Small- and Wide-Angle X-ray Scattering (SAXS/WAXS). XPCI-CT discriminates with high sensitivity the effects of MRT, MB and BB irradiations on both healthy and GBM-bearing brains producing a first-time 3D visualization and morphological analysis of the radio-induced lesions, MRT and MB induced tissue ablations, the presence of hyperdense deposits within specific areas of the brain and tumor evolution or regression with respect to the evaluation made few days post-irradiation with an in-vivo magnetic resonance imaging session. Histology, immunohistochemistry, SAXS/WAXS and XRF allowed identification and classification of these deposits as hydroxyapatite crystals with the coexistence of Ca, P and Fe mineralization, and the multi-technique approach enabled the realization, for the first time, of the map of the differential radiosensitivity of the different brain areas treated with MRT and MB. 3D XPCI-CT datasets enabled also the quantification of tumor volumes and Ca/Fe deposits and their full-organ visualization. The multi-scale and multi-technique approach enabled a detailed visualization and classification in 3D of the radio-induced effects on brain tissues bringing new essential information towards the clinical implementation of the MRT and MB radiation therapy techniques. [ABSTRACT FROM AUTHOR]