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This paper presents an algorithm to calibrate the center-of-rotation for X-ray tomography by using a machine learning approach, the Convolutional Neural Network (CNN). The algorithm shows excellent accuracy from the evaluation of synthetic data with various noise ratios. It is further validated with experimental data of four different shale samples measured at the Advanced Photon Source and at the Swiss Light Source. The results are as good as those determined by visual inspection and show better robustness than conventional methods. CNN has also great potential for reducing or removing other artifacts caused by instrument instability, detector non-linearity, etc. An open-source toolbox, which integrates the CNN methods described in this paper, is freely available through GitHub at tomography/xlearn and can be easily integrated into existing computational pipelines available at various synchrotron facilities. Source code, documentation and information on how to contribute are also provided. [ABSTRACT FROM AUTHOR]

Objectives: Despite the wide diffusion of minimally invasive approaches, such as laparoscopic (LRP) and robot-assisted radical prostatectomy (RALP), few studies compare the results of these techniques with the retropubic radical prostatectomy (RRP) approach. The aim of this study is to compare the surgical, functional, and oncological outcomes and cost-effectiveness of RRP, LRP, and RALP. Methods: A systematic review of the literature was performed in the PubMed and Embase databases in December 2013. A 'free-text' protocol using the term 'radical prostatectomy' was applied. A total of 16,085 records were found. The authors reviewed the records to identify comparative studies to include in the review. Results: 44 comparative studies were identified. With regard to the perioperative outcome, LRP and RALP were more time-consuming than RRP, but blood loss, transfusion rates, catheterisation time, hospitalisation duration, and complication rates were the most optimal in the laparoscopic approaches. With regard to the functional and oncological results, RALP was found to have the best outcomes. Conclusion: Our study confirmed the well-known perioperative advantage of minimally invasive techniques; however, available data were not sufficient to prove the superiority of any surgical approach in terms of functional and oncologic outcomes. On the contrary, cost comparison clearly supports RRP. © 2014 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Prostate cancer is the most frequently diagnosed cancer in men in the United States. Among the different available treatment options, radiation therapy is recommended for localized or even advanced disease. Erectile dysfunction (ED) often occurs after radiation therapy due to neurological, vascular, and endocrine mechanisms resulting in arterial tone alteration, pudendal-nerve neuropraxia, and lastly fibrosis. Considering the influence of quality of life on patients' treatment choice, radiation-therapy-induced ED prevention and treatment are major issues. In this narrative review, we briefly summarize and discuss the current state of the art on radiation-therapy-induced ED in PCa patients in terms of pathophysiology and available treatment options. [ABSTRACT FROM AUTHOR]

Data Exchange is a simple data model designed to interface, or 'exchange', data among different instruments, and to enable sharing of data analysis tools. Data Exchange focuses on technique rather than instrument descriptions, and on provenance tracking of analysis steps and results. In this paper the successful application of the Data Exchange model to a variety of X-ray techniques, including tomography, fluorescence spectroscopy, fluorescence tomography and photon correlation spectroscopy, is described. [ABSTRACT FROM AUTHOR]

Analysis of tomographic datasets at synchrotron light sources (including X-ray transmission tomography, X-ray fluorescence microscopy and X-ray diffraction tomography) is becoming progressively more challenging due to the increasing data acquisition rates that new technologies in X-ray sources and detectors enable. The next generation of synchrotron facilities that are currently under design or construction throughout the world will provide diffraction-limited X-ray sources and are expected to boost the current data rates by several orders of magnitude, stressing the need for the development and integration of efficient analysis tools. Here an attempt to provide a collaborative framework for the analysis of synchrotron tomographic data that has the potential to unify the effort of different facilities and beamlines performing similar tasks is described in detail. The proposed Python-based framework is open-source, platform- and data-format-independent, has multiprocessing capability and supports procedural programming that many researchers prefer. This collaborative platform could affect all major synchrotron facilities where new effort is now dedicated to developing new tools that can be deployed at the facility for real-time processing, as well as distributed to users for off-site data processing. [ABSTRACT FROM AUTHOR]

Transperineal laser ablation (TPLA) of the prostate is a new minimally invasive treatment option in men with lower urinary tract symptoms (LUTS) due to benign prostatic enlargement (BPE). The aim of this systematic review was to investigate the efficacy and safety of TPLA in the management of BPE. The primary outcomes were the improvement in urodynamic parameters (maximum urinary flow (Qmax) and postvoiding residue (PVR)) and LUTS relief, assessed using the IPSS questionnaire. The secondary outcomes were the preservation of sexual and ejaculatory functions, assessed with the IEEF-5 and MSHQ-EjD questionnaires, respectively, and rates of postoperative complications. We reviewed the literature for prospective or retrospective studies evaluating the use of TPLA in the treatment of BPE. A comprehensive search in PubMed, Scopus, Web of Science, and ClinicalTrials.gov was performed for English language articles published between January 2000 and June 2022. Pooled analysis of the included studies with available follow-up data for the outcomes of interest was additionally performed. After screening 49 records, six full-text manuscripts were identified, including two retrospective and four prospective non-comparative studies. Overall, 297 patients were included. All the studies independently reported a statistically significant improvement, from baseline, in Qmax, PVR, and IPSS score at each timepoint. Three studies additionally demonstrated that TPLA did not affect sexual function, reporting no change in the IEEF-5 score, and a statistically significant improvement in MSHQ-EjD score at each timepoint. Low rates of complications were recorded in all the included studies. Pooled analysis showed a clinically meaningful improvement in both micturition and sexual outcomes mean values at 1, 3, 6, and 12 months of follow-up, compared with baseline. Transperineal laser ablation of the prostate for the treatment of BPE showed interesting results in pilot studies. However, higher level and comparative studies are needed to confirm its efficacy in relieving obstructive symptoms and preserving sexual function. [ABSTRACT FROM AUTHOR]

Abstract: A new fuel consumption monitoring system was set up for research purpose in order to evaluate the energy performance of fishing vessels under different operating conditions. The system has been tested on two semi-pelagic pair trawlers in the Adriatic Sea with an engine power of around 900kW, and with length overall of around 30m. Both vessels work with a gear of similar design and size, the differences between the two vessels are in the propeller design and the hull material: the first with a controllable pitch propeller (CPP) and a metal hull, the second with a fixed pitch propeller (FPP) and a wooden hull. The fuel monitoring system conceived at CNR-ISMAR Ancona (Italy) consists of two mass flow sensors, one multichannel recorder and one GPS data logger. The working time duration, the vessel speed, the total fuel consumption and the instant fuel rate were logged by the system. A typical commercial round trip for a semi-pelagic trawler consists of several fishing operations (steaming, trawling sailing, etc.). Fuel consumption rate and vessel speed data were used to identify energy performance under different vessel-operating conditions. The highest fuel demands were during the trawling (130l/h at 4.4kn) and the steaming (100–130l/h at 11kn) phases. Fuel savings of up to 15% could be obtained by reducing the navigation speed of half a knot. [Copyright &y& Elsevier]

Synchrotron-based microtomography provides high resolution, but the resolution in large samples is often limited by the detector field of view and the pixel size. For some samples, only a small region of interest is relevant and local tomography is a powerful approach for retaining high resolution. Two methods are truncated tomography and zoom-in tomography. In this article we use existing theoretical results to estimate the error present in truncated and zoom-in tomographic reconstructions. These errors agree with the errors calculated from exact tomographic reconstructions. We argue in a heuristic manner why zoom-in tomography is superior to the truncated tomography in terms of the reconstruction error. However, the theoretical formula is not usable in practice because it requires the complete high-resolution reconstruction to be known. To solve this problem we proposed a practical method for estimating the error in zoom-in and truncated tomographies. The results using this estimation method are in very good agreement with our experimental results. [ABSTRACT FROM AUTHOR]

A third-generation synchrotron radiation source provides enough brilliance to acquire complete tomographic data sets at 100 nm or better resolution in a few minutes. To take advantage of such high-brilliance sources at the Advanced Photon Source, we have constructed a pipelined data acquisition and reconstruction system that combines a fast detector system, high-speed data networks, and massively parallel computers to rapidly acquire the projection data and perform the reconstruction and rendering calculations. With the current setup, a data set can be obtained and reconstructed in tens of minutes. A specialized visualization computer makes rendered three-dimensional (3D) images available to the beamline users minutes after the data acquisition is completed. This system is capable of examining a large number of samples at sub-μm 3D resolution or studying the full 3D structure of a dynamically evolving sample on a 10 min temporal scale. In the near future, we expect to increase the spatial resolution to below 100 nm by using zone-plate x-ray focusing optics and to improve the time resolution by the use of a broadband x-ray monochromator and a faster detector system. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Despite the increased brilliance of the new generation synchrotron sources, there is still a challenge with high‐resolution scanning of very thick and absorbing samples, such as a whole mouse brain stained with heavy elements, and, extending further, brains of primates. Samples are typically cut into smaller parts, to ensure a sufficient X‐ray transmission, and scanned separately. Compared with the standard tomography setup where the sample would be cut into many pillars, the laminographic geometry operates with slab‐shaped sections significantly reducing the number of sample parts to be prepared, the cutting damage and data stitching problems. In this work, a laminography pipeline for imaging large samples (>1 cm) at micrometre resolution is presented. The implementation includes a low‐cost instrument setup installed at the 2‐BM micro‐CT beamline of the Advanced Photon Source. Additionally, sample mounting, scanning techniques, data stitching procedures, a fast reconstruction algorithm with low computational complexity, and accelerated reconstruction on multi‐GPU systems for processing large‐scale datasets are presented. The applicability of the whole laminography pipeline was demonstrated by imaging four sequential slabs throughout an entire mouse brain sample stained with osmium, in total generating approximately 12 TB of raw data for reconstruction. [ABSTRACT FROM AUTHOR]

Full‐field transmission X‐ray microscopy (TXM) is a well established technique, available at various synchrotron beamlines around the world as well as by laboratory benchtop devices. One of the major TXM challenges, due to its nanometre‐scale resolution, is the overall instrument stability during the acquisition of the series of tomographic projections. The ability to correct for vertical and horizontal distortions of each projection image during acquisition is necessary in order to achieve the effective 3D spatial resolution. The effectiveness of such an image alignment is also heavily influenced by the absorption properties and strong contrast of specific features in the scanned sample. Here it is shown that nanoporous gold (NPG) can be used as an ideal 3D test pattern for evaluating and optimizing the performance of a TXM instrument for hard X‐rays at a synchrotron beamline. Unique features of NPG, such as hierarchical structures at multiple length scales and high absorbing capabilities, makes it an ideal choice for characterization, which involves a combination of a rapid‐alignment algorithm applied on the acquired projections followed by the extraction of a set of both 2D‐ and 3D‐descriptive image parameters. This protocol can be used for comparing the efficiency of TXM instruments at different synchrotron beamlines in the world or benchtop devices, based on a reference library of scanned NPG samples, containing information about the estimated horizontal and vertical alignment values, 2D qualitative parameters and quantitative 3D parameters. The possibility to tailor the ligament sizes of NPG to match the achievable resolution in combination with the high electron density of gold makes NPG an ideal 3D test pattern for evaluating the status and performance of a given synchrotron‐based or benchtop‐based TXM setup. Nanoporous gold is hereby proposed as an ideal 3D pattern for characterizing the performance of hard X‐ray nano‐imaging systems. While a wide range of techniques such as ptychography, holography or other forms of nano‐probes will benefit from this development, here its utility is demonstrated by characterizing the transmission X‐ray microscope at beamline P05, DESY, which is a full‐field technique. [ABSTRACT FROM AUTHOR]

[Display omitted] Metal-organic framework (MOF) materials are promising precursors to transition into metal-nitrogen-carbon (M-N-C) catalysts with high catalytic performance. Pyrolysis is one of the most common ways to convert MOFs into electrically conductive MOF-derived M-N-C catalysts. General interests in using MOFs as precursors derive from changing the MOFs' porous structure into the carbonaceous frame. However, this favorable structure is not always maintained, with the reason unidentified since pyrolysis is currently still more of an empirical process. Understanding the pyrolysis processes leading to the transformation of MOFs into M-N-C catalysts is essential to broaden the development of MOF-derived catalysts. We report here complete chemical and morphological evolution and transformation of two commercial MOFs with the same sodalite topology, the ZIF-8 and ZIF-67, via series of in situ and ex situ techniques. The results reveal that the structure of the ZIF-67 collapses after the pyrolysis due to the graphitization of the carbon. Graphitization is catalyzed by the metallic cobalt particles formed when the temperature rose above 460 °C. The ZIF-8 was found to be a promising precursor material since most of the metal evaporates at the early stages and does not aggregate to form metal particles. However, the insufficient metal-N active sites and intrinsic low electrocatalysis availability of Zn limit the performance of the final catalyst. To maintain the porous structure of MOFs it is important to control the metal species and prevent them from agglomeration. Direct utilization of high-concentration MOFs as pyrolysis precursors is not recommended without rational design to inhibit agglomeration and graphitization that are undesirable for catalyst activity. [ABSTRACT FROM AUTHOR]

However, if acquisition is extremely fast and Graph HT ht , then the initial formula is computationally more favorable. We also added functionality for setting the rotation angle of each Graph HT ht slice to be able to follow different structures inside the sample. Implementation of this functionality is straightforward and only involves rotation of Graph HT ht planes by using a rotation matrix in 3D. [Extracted from the article]

Human mentality develops with age and is altered in psychiatric disorders, though their underlying mechanism is unknown. In this study, we analyzed nanometer-scale three-dimensional structures of brain tissues of the anterior cingulate cortex from eight schizophrenia and eight control cases. The distribution profiles of neurite curvature of the control cases showed a trend depending on their age, resulting in an age-correlated decrease in the standard deviation of neurite curvature (Pearson's r = -0.80, p = 0.018). In contrast to the control cases, the schizophrenia cases deviate upward from this correlation, exhibiting a 60% higher neurite curvature compared with the controls (p = 7.8 × 10−4). The neurite curvature also showed a correlation with a hallucination score (Pearson's r = 0.80, p = 1.8 × 10−4), indicating that neurite structure is relevant to brain function. This report is based on our 3D analysis of human brain tissues over a decade and is unprecedented in terms of the number of cases. We suggest that neurite curvature plays a pivotal role in brain aging and can be used as a hallmark to exploit a novel treatment of schizophrenia. [ABSTRACT FROM AUTHOR]

It is well established that increasing mesh number in the circumference of a diamond-mesh trawl codend can reduce size selection for round fish, whereas selection for flat fish species is unaffected. This effect has also been documented in Mediterranean trawl fisheries. In contrast, no information is available with regard to the effect of increasing mesh number in the circumference of square-mesh codends on the size selection of round fish and flat fish species. A field study was devised to bridge this gap and formulate proposals aimed at improving trawl fishery management. Size selection data were collected for a round fish species, red mullet (Mullus barbatus), and two flat fish species, Mediterranean scaldfish (Arnoglossus laterna) and solenette (Buglossidium luteum). Fishing trials were conducted in the Adriatic Sea (Central Mediterranean) using three square-mesh codends that differed only in mesh number around the circumference. Results demonstrated that increasing the number of meshes from 107 to 213 reduced the 50% retention length (L50) for red mullet by 2.5 cm but did not affect size selection for the two flat fish species. In some fisheries, regulatory provisions regarding the number of meshes in the circumference should therefore be carefully considered both for diamond- and square-mesh codends. [ABSTRACT FROM AUTHOR]

Galeus melastomus (blackmouth catshark) is often caught as bycatch in demersal trawls in the Mediterranean. In order to reduce bycatches of shark we tested an excluder grid with 90 mm bar spacing during experimental fishing in the Tyrrhenian Sea (Western Mediterranean). Data collected made it possible to simultaneously evaluate catch losses of two commercial species: Nephrops norvegicus (Norway lobster) and Phycis blennoides (greater forkbeard). The escape outlet ahead of the grid and the codend were both mounted with a cover in order to collect escaped fish ahead of the grid and through the codend meshes. We used a structural model to estimate the contribution of the individual selective processes consisting of the excluder grid and the size selective codend. The 90 mm excluder grid did not prove to be efficient in excluding G. melastomus , while it excuded more of P. blennoides . Catches of N. norvegicus were also affected by the presence of the grid, but not as much as the catches of other two species. The results obtained for the experimental grid + codend setup were then compared with the estimated selectivity for the “codend alone” setup. Furthermore, by way of explorative simulation with other grid bar spacing, we concluded that reducing the grid bar spacing to 70 mm would provide better compromise between the reduction of G. melastomus as bycatch and the catch rate of P. blennoides and N. norvegicus . [ABSTRACT FROM AUTHOR]

The handling of datasets at scientific user facilities is becoming progressively more challenging as advances in sources and detectors drive increasingly aggressive data acquisition rates. The ability to share and process these data depends on the ability of the originator of the data and the persons making use of that data to unequivocally agree on what these data mean. This understanding is driven by use of standardized data formats. [ABSTRACT FROM AUTHOR]

Complex dynamic tomographic experiments at brilliant X-ray light sources require real-time feedback on the sample changes with respect to environmental conditions, selecting representative regions of interest for high-resolution scanning, and on-demand data saving mechanisms for storing only relevant projections acquired by fast area detectors and reducing data volumes. Here the implementation details of a 3D real-time imaging monitoring instrument, with zooming to a volume of interest with easy-to-use visualization via ImageJ, a tool familiar to most beamline users, is presented. The instrument relies on optimized data flow between the detector and processing machines and is implemented on commodity computers. The instrument has been developed at beamline 2-BM of the Advanced Photon Source, where the automatic lens changing mechanism for zooming is implemented with an Optique Peter microscope. Performance tests demonstrate the ability to process more than 3 GB of projection data per second and generate real-time 3D zooming with different magnification. These new capabilities are essential for new APS Upgrade instruments such as the projection microscope under development at beamline 32-ID. The efficacy of the proposed instrument was demonstrated during an in situ tomographic experiment on ice and gas hydrate formation in porous samples. [ABSTRACT FROM AUTHOR]

Synchrotron radiation X-ray tomographic microscopy (SRXTM) was used to characterize the three-dimensional microstructure, geometry and distribution of different phases in two shale samples obtained from the North Sea (sample N1) and the Upper Barnett Formation in Texas (sample B1). Shale is a challenging material because of its multiphase composition, small grain size, low but significant amount of porosity, as well as strong shape- and lattice-preferred orientation. The goals of this round-robin project were to (i) characterize microstructures and porosity on the micrometer scale, (ii) compare results measured at three synchrotron facilities, and (iii) identify optimal experimental conditions of high-resolution SRXTM for fine-grained materials. SRXTM data of these shales were acquired under similar conditions at the Advanced Light Source (ALS) of Lawrence Berkeley National Laboratory, USA, the Advanced Photon Source (APS) of Argonne National Laboratory, USA, and the Swiss Light Source (SLS) of the Paul Scherrer Institut, Switzerland. The data reconstruction of all datasets was handled under the same procedures in order to compare the data quality and determine phase proportions and microstructures. With a 10× objective lens the spatial resolution is approximately 2 µm. The sharpness of phase boundaries in the reconstructed data collected from the APS and SLS was comparable and slightly more refined than in the data obtained from the ALS. Important internal features, such as pyrite (high-absorbing), and low-density features, including pores, fractures and organic matter or kerogen (low-absorbing), were adequately segmented on the same basis. The average volume fractions of low-density features for sample N1 and B1 were estimated at 6.3 (6)% and 4.5 (4)%, while those of pyrite were calculated to be 5.6 (6)% and 2.0 (3)%, respectively. The discrepancy of data quality and volume fractions were mainly due to different types of optical instruments and varying technical set-ups at the ALS, APS and SLS. [ABSTRACT FROM AUTHOR]

Abstract: Atactic polystyrene, one of the most widely used chemical products, was subjected to novel chemically oxidative treatments able to trigger a great variety of physical and chemical changes in the polymer''s chains. The oxidized polystyrene samples, when analyzed with Fourier transform infrared spectroscopy (FTIR) clearly showed the formation of carbonyl groups and hydroxyl groups, which increased with the increase in the strength of chemically oxidative treatments. In fungal degradation tests deploying Curvularia species, the fungus colonized the oxidized samples within 9 weeks. Colonization was confirmed by microscopic examination, which showed that the hyphae had adhered to and penetrated the polymer''s structure in all the treated samples. Such colonization and adhesion by microorganisms are a fundamental prerequisite for biodegradation of polymers. [Copyright &y& Elsevier]

Abstract: A clustering procedure is introduced based on the Hausdorff distance as a similarity measure between clusters of elements. The method is applied to the financial time series of the Dow Jones industrial average (DJIA) index to find companies that share a similar behavior. Comparisons are made with other linkage algorithms. [Copyright &y& Elsevier]

A chaotic map algorithm is proposed to study similarity-based knowledge of temporal patterns. Several information sources can be regarded as time series, both in scientific and technological fields such as nuclear physics, computer network, biomedical signals, and many others. The application of an automatic knowledge discovery mechanism has a strong impact on system science and engineering. The advantage of the proposed algorithm is due to its capability to extract meaningful features from complex data sets, as temporal patterns, without teacher. A case study has been carried on biomedical Signals, such as electroencephalographic records, to recognize patterns affected by the Huntington's disease, one of the most dangerous pathology of the central nervous system. The chaotic map algorithm succeeds in distinguishing between pathological and normal patterns, with high values of both sensitivity and specificity. [ABSTRACT FROM AUTHOR]

For reconstructing large tomographic datasets fast, filtered backprojection‐type or Fourier‐based algorithms are still the method of choice, as they have been for decades. These robust and computationally efficient algorithms have been integrated in a broad range of software packages. The continuous mathematical formulas used for image reconstruction in such algorithms are unambiguous. However, variations in discretization and interpolation result in quantitative differences between reconstructed images, and corresponding segmentations, obtained from different software. This hinders reproducibility of experimental results, making it difficult to ensure that results and conclusions from experiments can be reproduced at different facilities or using different software. In this paper, a way to reduce such differences by optimizing the filter used in analytical algorithms is proposed. These filters can be computed using a wrapper routine around a black‐box implementation of a reconstruction algorithm, and lead to quantitatively similar reconstructions. Use cases for this approach are demonstrated by computing implementation‐adapted filters for several open‐source implementations and applying them to simulated phantoms and real‐world data acquired at the synchrotron. Our contribution to a reproducible reconstruction step forms a building block towards a fully reproducible synchrotron tomography data processing pipeline. [ABSTRACT FROM AUTHOR]

In situ synchrotron X-ray microtomography was used to characterize the bulk deformation behavior by computing the Poisson's ratio of expanded thermoplastic polyurethane (eTPU) molded bead foams used in footwear midsole during compression. Quantitative data on morphological characteristics were obtained using an iterative image processing workflow. Image correlation on the 4D datasets using DVC was performed to calculate the volumetric and axial strain to estimate the Poisson ratio. Strain maps from DVC showed the influence of variability in ligament thickness distribution on the global mechanical behavior exhibited which dominated the response seen in these bead foams. Finally, our results showed a strong correlation between Poisson ratio and distribution of ligament thickness in foams. [ABSTRACT FROM AUTHOR]

[Display omitted] Transition metal-nitrogen-carbon materials (M-N-C catalysts) are promising electrocatalysts in polymer electrolyte fuel cells (PEFCs) and electrolyzer applications. High temperature treatment in inert atmosphere (pyrolysis) is the essential, most common method for the synthesis of M-N-C catalysts and critical to achieve high electrocatalytic activity and electronic conductivity. To this day, despite many uses and successful implementations in materials manufacturing, pyrolysis has been an entirely empirical technology, with process control and optimization relying exclusively on "Edisonian" approach. The knowledge gap in the mechanism about how the precursor is being transformed into catalysts hinders further development of the M-N-C catalysts regardless of the precursor class and processing protocols. Herein, we probed the morphological evolution and chemical transformation of a nitrogen-containing charge transfer organic salt, mixed with transition metal (iron) salt and amorphous silica powder (precursor) during the pyrolysis process via a combination of in situ synchrotron and laboratory-based diagnostic techniques. The pyrolysis process is found to be divided into three stages. During a controlled temperature ramp, the selected organic N-C precursor (nicarbazin) began melting and decomposing just below 400 °C, forming a certain number of micrometer-scale pores and pathways. With increase in temperature from 400 °C to 900 °C, amorphous carbon domains started forming, and reduced (metallic) iron nanoclusters appeared, being dispersed uniformly throughout the carbonaceous matrix. When temperature advanced above 900 °C, graphitization of carbon commenced, associated with appearance and evolution of atomically dispersed metal-nitrogen moieties in the carbonaceous matrix. As the graphitization advanced further, a secondary process of agglomeration of metal nanoparticles occurred. Multi-analytical technique observations conducted here provide a base for rational design and optimization of M-N-C electrocatalysts via pyrolysis. [ABSTRACT FROM AUTHOR]

Accurate representations of the 3D structure within a lithium‐ion battery are key to understanding performance limitations. However, obtaining exact reconstructions of electrodes, where the active particles, the carbon black and polymeric binder domain, and the pore space are visualized is challenging. Here, it is shown that multimodal imaging can be used to overcome this challenge. High‐resolution ptychographic X‐ray computed tomography are combined with lower resolution but higher contrast transmission X‐ray tomographic microscopy to obtain 3D reconstructions of pristine and cycled graphite‐silicon composite electrodes. This cross‐correlation enables quantitative analysis of the surface of active particles, including the heterogeneity of carbon‐black and binder domain and solid‐electrolyte interphase coverage. Capturing the active particles as well as the carbon black‐binder domain allows using these segmented structures for electrochemical simulations to highlight the influence of the particle embedding on local state of charge heterogeneities. [ABSTRACT FROM AUTHOR]

An iterative method has been developed to improve the quality of 3D tomography data with limited angular access. Within 10 iteration cycles, the reconstructed data error can be improved by an order of magnitude and reach below 1%. This algorithm was applied to high pressure tomography data collected in a panoramic diamond anvil cell with the transmission x-ray microscopy technique, in which only 135° of data can be obtained. We found that the volumes measured for a tin (Sn) particle across the β-Sn to body-centered-tetragonal (bct) high pressure phase transition match the equation of state for Sn determined by x-ray diffraction. This result demonstrates the exciting potential for a wide range of high pressure imaging studies which are now enabled by use of the iteration method to reconstruct 3D tomography data. [ABSTRACT FROM AUTHOR]

Even after nearly a century of extensive use of aluminum alloys in structural applications, our understanding of such precipitation-strengthened materials is far from complete. With the advent of next generation advanced characterization techniques, our ability to probe materials in unique ways and at different length scales has established a new paradigm for devising new pathways to alloy design by engineering materials and tailoring specific properties at the nanoscale. Here, we perform in situ nanomechanical testing in conjunction with synchrotron-based hard X-ray nanotomography to capture initiation and evolution of damage in 3D in Al–Cu alloys. Precipitates in these alloys are seen to exhibit unprecedented localized deformation in compression, which is attributed to novel observations of kinking in these brittle second-phase particles, accompanied with the generation of a fine polycrystalline texture in the adjacent matrix. We observe a size-dependent transition in precipitate deformation behavior that has been thoroughly investigated using a comprehensive correlative approach. Image 1 [ABSTRACT FROM AUTHOR]

A unique correlative approach for automated segmentation of large 3D nanotomography datasets obtained using Transmission X-ray Microscopy (TXM) in an Al-Cu alloy has been introduced. Automated segmentation using a Convolutional Neural Network (CNN) architecture based on a deep learning approach was employed. This extremely versatile technique is capable of emulating the manual segmentation process effectively. Coupling this technique with post-scanning SEM imaging ensured precise estimation of 3D morphological parameters from nanotomography. The segmentation process as well as subsequent analysis was expedited by several orders of magnitude. Quantitative comparison between segmentation performed manually and using the CNN architecture established the accuracy of this automated technique. Its ability to robustly process ultra-large volumes of data in relatively small time frames can exponentially accelerate tomographic data analysis, possibly opening up novel avenues for performing 4D characterization experiments with finer time steps. [ABSTRACT FROM AUTHOR]

Xi‐cam is an extensible platform for data management, analysis and visualization. Xi‐cam aims to provide a flexible and extensible approach to synchrotron data treatment as a solution to rising demands for high‐volume/high‐throughput processing pipelines. The core of Xi‐cam is an extensible plugin‐based graphical user interface platform which provides users with an interactive interface to processing algorithms. Plugins are available for SAXS/WAXS/GISAXS/GIWAXS, tomography and NEXAFS data. With Xi‐cam's `advanced' mode, data processing steps are designed as a graph‐based workflow, which can be executed live, locally or remotely. Remote execution utilizes high‐performance computing or de‐localized resources, allowing for the effective reduction of high‐throughput data. Xi‐cam's plugin‐based architecture targets cross‐facility and cross‐technique collaborative development, in support of multi‐modal analysis. Xi‐cam is open‐source and cross‐platform, and available for download on GitHub. [ABSTRACT FROM AUTHOR]

A unique approach to correlating an evolving 3D microstructure in an Al-Cu alloy and its micro-scale mechanical properties has been introduced. Using these nanoscale three-dimensional microstructures derived from Transmission X-ray Microscopy (TXM), individual contributions from different strengthening mechanisms were quantified. The spatial distribution and morphology of the individual θ′ and θ phases were seen to play an important role in influencing dislocation storage. Uniaxial micro-compression experiments were used to quantify the stress-strain response of the alloy at different aging times. Transmission electron microscopy (TEM) aided in discerning dislocation activity at these precipitates. A model is proposed to accurately predict the variation in yield stress by using appropriate morphological parameters from the 3D microstructure and its validity has been corroborated using experimental measurements. Distributions of 2D and 3D inter-precipitate spacing were seen to provide crucial insights on influencing deformation in such precipitation-strengthened alloys. Finally, the transition in deformation behavior and origin of numerous strain bursts were investigated using in situ micropillar compression testing. [ABSTRACT FROM AUTHOR]

The impact of calendering process on the geometric characteristics and electrochemical performance of LiNi 1/3 Mn 1/3 Co 1/3 O 2 (NMC) electrode was investigated in this study. The geometric properties of NMC electrodes with different calendering conditions, such as porosity, pore size distribution, particle size distribution, specific surface area and tortuosity were calculated from the computed tomography data of the electrodes. A synchrotron transmission X-ray microscopy tomography system at the Advanced Photon Source of the Argonne National Laboratory was employed to obtain the tomography data. The geometric and electrochemical analysis show that calendering can increase the electrochemically active area, which improves rate capability. However, more calendering will result in crushing of NMC particles, which can reduce the electrode capacity at relatively high C rates. This study shows that the optimum electrochemical performance of NMC electrode at 94:3:3 weight ratio of NMC:binder:carbon black can be achieved by calendering to 3.0 g/cm 3 NMC density. [ABSTRACT FROM AUTHOR]

The development of low impact and fuel efficient (LIFE) fishing is being paid growing attention. Pot fishing has lower environmental impact and fuel consumption than most other fishing methods. However, pots typically have low capture efficiency for most ground-fish species, and efforts to develop effective commercial pots are needed. Bycatch of red king crab ( Paralithodes camtschaticus ) is a severe problem in the coastal fishery for cod ( Gadus morhua ) in the Barents Sea. In a previous publication, we demonstrated that cod pots floated off the bottom eliminated this problem. Our original bottom-set cod pot has two entrances in order to increase the rate of entry of fish, but when this pot is floated, fish that search for food by following chemical cues up-current will only encounter the entrance that is oriented down-current. We therefore compared the catch rates of floated pots with one and two entrances, and predicted that the new design with only one entrance would achieve higher catch rates due to a lower rate of escape. Pots with one entrance caught significantly more cod and haddock ( Melanogrammus aeglefinus ) than pots with two entrances. The catch rate of cod above minimum landing size (≥44 cm) of pots with one entrance was 82% higher than that of pots with two entrances. Pots that were snagged and did not float properly caught large numbers of king crab. The larger catches of pots with one entrance could be explained by lower escape rate from this design. The observed difference in catch rates between the two pot types indicates that more than 50% of the large cod and haddock that entered the pot with two entrances escaped. There is therefore great potential for increased catching efficiency of pots through improved pot design. [ABSTRACT FROM AUTHOR]

Acquired Hemophilia A (AHA) is a rare bleeding diathesis characterized by the development of autoantibodies against factor VIII (FVIII). About half of the cases are idiopathic and the other half are associated with autoimmune diseases, postpartum problems, infections, inflammatory bowel disease, drugs, lymphoproliferative disorders or solid tumors . AHA is associated with malignancies in 7-15% of cases. We report a case of AHA in a 65 year old patient with prostatic carcinoma, who underwent retropubic radical prostatectomy (RP). [ABSTRACT FROM AUTHOR]

Bladder cancer is very common and most cases are diagnosed as nonmuscle invasive disease, which is characterized by its propensity to recur and progress. Intravesical therapy is used to delay recurrence and progression, while cystectomy is reserved for patients who are refractory to transurethral resection and intravesical therapy. There is an increasing interest in methods to enhance the delivery of intravesical chemotherapeutic agents to improve efficacy. In vitro and in vivo studies demonstrated that electro-osmosis of mitomycin C (MMC) is more effective in delivering this drug into the urothelium, lamina propria, and superficial muscle layers of the bladder wall than is passive transport. Higher MMC tissue concentrations might have a clinical impact in the treatment of nonmuscle invasive bladder cancer (NMIBC). In randomized trials, intravesical electro-osmotic MMC was associated with superior response rate in high-risk NMIBC cancer, compared with passive diffusion MMC transport. New strategies such as intravesical Bacillus Calmette-Guerin (BCG) combined with electro-osmotic MMC as well as intravesical pre-operative electro-osmotic MMC provided promising results in terms of higher remission rates and longer remission times. Device-assisted intravesical chemotherapy may be a useful ancillary procedure in the treatment of NMIBC. Its evaluation must be planned with respect to the technical functioning of equipment and their use for a clear purpose to avoid the financial and human costs associated with incorrect therapies. [ABSTRACT FROM AUTHOR]

To investigate geometric and electrochemical characteristics of Li ion battery electrode with different packing densities, lithium cobalt oxide (LiCoO 2 ) cathode electrodes were fabricated from a 94:3:3 (wt%) mixture of LiCoO 2 , polymeric binder, and super-P carbon black and calendered to different densities. A synchrotron X-ray nano-computed tomography system with a spatial resolution of 58.2 nm at the Advanced Photon Source of the Argonne National Laboratory was employed to obtain three dimensional morphology data of the electrodes. The morphology data were quantitatively analyzed to characterize their geometric properties, such as porosity, tortuosity, specific surface area, and pore size distribution. The geometric and electrochemical analysis reveal that high packing density electrodes have smaller average pore size and narrower pore size distribution, which improves the electrical contact between carbon-binder matrix and LiCoO 2 particles. The better contact improves the capacity and rate capability by reducing the possibility of electrically isolated LiCoO 2 particles and increasing the electrochemically active area. The results show that increase of packing density results in higher tortuosity, but electrochemically active area is more crucial to cell performance than tortuosity at up to 3.6 g/cm 3 packing density and 4 C rate. [ABSTRACT FROM AUTHOR]

New technological advancements in synchrotron light sources enable data acquisitions at unprecedented levels. This emergent trend affects not only the size of the generated data but also the need for larger computational resources. Although beamline scientists and users have access to local computational resources, these are typically limited and can result in extended execution times. Applications that are based on iterative processing as in tomographic reconstruction methods require high-performance compute clusters for timely analysis of data. Here, time-sensitive analysis and processing of Advanced Photon Source data on geographically distributed resources are focused on. Two main challenges are considered: (i) modeling of the performance of tomographic reconstruction workflows and (ii) transparent execution of these workflows on distributed resources. For the former, three main stages are considered: (i) data transfer between storage and computational resources, (i) wait/queue time of reconstruction jobs at compute resources, and (iii) computation of reconstruction tasks. These performance models allow evaluation and estimation of the execution time of any given iterative tomographic reconstruction workflow that runs on geographically distributed resources. For the latter challenge, a workflow management system is built, which can automate the execution of workflows and minimize the user interaction with the underlying infrastructure. The system utilizes Globus to perform secure and efficient data transfer operations. The proposed models and the workflow management system are evaluated by using three high-performance computing and two storage resources, all of which are geographically distributed. Workflows were created with different computational requirements using two compute-intensive tomographic reconstruction algorithms. Experimental evaluation shows that the proposed models and system can be used for selecting the optimum resources, which in turn can provide up to 3.13× speedup (on experimented resources). Moreover, the error rates of the models range between 2.1 and 23.3% (considering workflow execution times), where the accuracy of the model estimations increases with higher computational demands in reconstruction tasks. [ABSTRACT FROM AUTHOR]

The processing of tomographic synchrotron data requires advanced and efficient software to be able to produce accurate results in reasonable time. In this paper, the integration of two software toolboxes, TomoPy and the ASTRA toolbox, which, together, provide a powerful framework for processing tomographic data, is presented. The integration combines the advantages of both toolboxes, such as the user-friendliness and CPU-efficient methods of TomoPy and the flexibility and optimized GPU-based reconstruction methods of the ASTRA toolbox. It is shown that both toolboxes can be easily installed and used together, requiring only minor changes to existing TomoPy scripts. Furthermore, it is shown that the efficient GPU-based reconstruction methods of the ASTRA toolbox can significantly decrease the time needed to reconstruct large datasets, and that advanced reconstruction methods can improve reconstruction quality compared with TomoPy's standard reconstruction method. [ABSTRACT FROM AUTHOR]

In Europe, there had previously been a series of synchrotron X-ray computed tomography (XCT) workshops, so-called "Beamline Jockey Days" workshops, organized by national synchrotron radiation facilities. In this virtual workshop, we shared the experience of beamline and computational scientists directly involved with operation, presenting the current pipeline for data acquisition and reconstruction at the XCT beamlines. The virtual workshop on "X-ray Tomography at Synchrotron Facilities: Pipeline for Data Acquisition and Reduction" was held February 22-26, 2021, hosted by Elettra Sincrotrone Trieste (Italy) and organized through a joint collaboration between the Advanced Light Source (USA), the Advanced Photon Source (USA), the Diamond Light Source (UK), the European Synchrotron Radiation Facility (France), and Elettra Sincrotrone Trieste (Italy). [Extracted from the article]

The electrode of Li-ion batteries is required to be chemically and mechanically stable in the electrolyte environment for in situ monitoring by transmission X-ray microscopy (TXM). Evidence has shown that continuous irradiation has an impact on the microstructure and the electrochemical performance of the electrode. To identify the root cause of the radiation damage, a wire-shaped electrode is soaked in an electrolyte in a quartz capillary and monitored using TXM under hard X-ray illumination. The results show that expansion of the carbon-binder matrix by the accumulated X-ray dose is the key factor of radiation damage. For in situ TXM tomography, intermittent X-ray exposure during image capturing can be used to avoid the morphology change caused by radiation damage on the carbon-binder matrix. [ABSTRACT FROM AUTHOR]

Metal matrix composites (MMCs) offer high strength, high stiffness, low density, and good fatigue resistance, while maintaining cost an acceptable level. Fatigue resistance of MMCs depends on many aspects of composite microstructure. Fatigue crack growth behavior is particularly dependent on the reinforcement characteristics and matrix microstructure. The goal of this work is to obtain a fundamental understanding of fatigue crack growth behavior in SiC particle-reinforced 2080 Al alloy composites. In situ X-ray synchrotron tomography was performed on two samples at low (R=0.1) and at high (R=0.6) R-ratios. The resulting reconstructed images were used to obtain three-dimensional (3D) rendering of the particles and fatigue crack. Behaviors of the particles and crack, as well as their interaction, were analyzed and quantified. Four-dimensional (4D) visual representations were constructed to aid in the overall understanding of damage evolution. [ABSTRACT FROM AUTHOR]

Highlights: [•] Combined 3D microstructural characterization and mechanical properties of inclusions in Al 7075 alloys. [•] 3D microstructural characterization of inclusions was obtained by X-ray synchrotron tomography. [•] Mechanical properties of inclusions was obtained by CSM technique in nanoindentation. [•] Quantitative characterization of volume fraction, size, and morphology of inclusions and porosity. [Copyright &y& Elsevier]

Abstract: Synchrotron source X-ray micro-computed tomography was used for non-destructive three-dimensional (3-D) imaging of porous alumina structures, in which the porosity was induced by a granular porogen, added in amounts of 10–60vol.%. Microstructural characteristics related to transport properties, including connectivity and tortuosity, were measured from the resulting 3-D data sets. Connectivity of 94.5–99.6% was measured for samples produced with 35–60% porogen (30.8–49.6% porosity). Two methods of calculating tortuosity, path length ratio and gas phase flux were compared, and the effect of sample volume on calculated tortuosity value and computational time was examined. Average sample tortuosity calculated using the two methods generally agreed, although significant directional anisotropy was detected in some cases for the gas phase flux calculation method. Tortuosity values as low as 1.5 were measured for alumina components with 49.6% porosity. [Copyright &y& Elsevier]

In the management of non-muscle invasive bladder cancer (NMIBC), high-level evidence supports the widespread practice of intravesical therapy with mitomycin-C (MMC). Randomized trials showed a significant reduction in short-term recurrence compared with transurethral resection of bladder tumor (TURBT) alone, but little effect on long-term and no impact at all in preventing progression. Electromotive drug administration (EMDA®) offers a means of controlling and enhancing the tissue transport of certain drugs, in order to increase their efficacy. In both laboratory and clinical studies, intravesical electromotive drug administration (EMDA) increases MMC bladder uptake, resulting in an improved clinical efficacy in NMIBC without systemic side effects. New frameworks for treatment of NMIBC -- e.g., sequential intravesical BCG and EMDA/MMC, as well as intravesical EMDA/MMC immediately before TURBT -- have provided promising preliminary results with higher remission rates and longer remission times, and they are a priority to minimise the costs of disease management. These findings suggest EMDA-enhanced MMC efficacy against urothelial cancer could be a major therapeutic breakthrough in the treatment of NMIBC. [ABSTRACT FROM AUTHOR]

Abstract: Bone''s microporosities play important biologic and mechanical roles. Here, we quantified 3D changes in cortical osteocyte-lacunae and other small porosities induced by estrogen withdrawal and two different osteoporosis treatments. Unlike 2D measurements, these data collected via synchrotron radiation-based μCT describe the size and 3D spatial distribution of a large number of porous structures. Six-month old female Sprague–Dawley rats were separated into four groups of age-matched controls, untreated OVX, OVX treated with PTH, and OVX treated with Alendronate (ALN). Intracortical microporosity of the medial quadrant of the femoral diaphysis was quantified at endosteal, intracortical, and periosteal regions of the samples, allowing the quantification of osteocyte lacunae that were formed primarily before versus after the start of treatment. Across the overall thickness of the medial cortex, lacunar volume fraction (Lc.V/TV) was significantly lower in ALN treated rats compared to PTH. In the endosteal region, average osteocyte lacunar volume () of untreated OVX rats was significantly lower than in age-matched controls, indicating a decrease in osteocyte lacunar size in bone formed on the endosteal surface after estrogen withdrawal. The effect of treatment (OVX, ALN, PTH) on the number of lacunae per tissue volume (Lc.N/TV) was dependent on the specific location within the cortex (endosteal, intracortical, periosteal). In both the endosteal and intracortical regions, Lc.N/TV was significantly lower in ALN than in untreated OVX, suggesting a site-specific effect in osteocyte lacuna density with ALN treatment. There also were a significantly greater number of small pores (5–100μm3 in volume) in the endosteal region for PTH compared to ALN. The mechanical impact of this altered microporosity structure is unknown, but might serve to enhance, rather than deteriorate bone strength with PTH treatment, as smaller osteocyte lacunae may be better able to absorb shear forces than larger lacunae. Together, these data demonstrate that current treatments of osteoporosis can alter the number, size, and distribution of microporosities in cortical rat lamellar bone. [Copyright &y& Elsevier]

The article focuses on the development of new method which suppresses ring artefacts during anistropic computerized X-ray tomography. It discusses the application of an analytical formula involving matrix-vector multiplication under regularization parameter. It also highlights the method efficacy through the experiment using calcified shark cartilage and metal matrix composite samples.

The permeability of the upper mantle controls melt segregation beneath spreading centers. Reconciling contradictory geochemical and geophysical observations at ocean ridges requires a better understanding of transport properties in partially molten rocks. Using x-ray synchrotron microtomography, we obtained three-dimensional data on melt distribution for mantle peridotite with various melt fractions. At melt fractions as low as 0.02, triple junctions along grain edges dominated the melt network; there was no evidence of an abrupt change in the fundamental character of melt extraction as melt fraction increased to 0.2. The porosity of the partially molten region beneath ocean ridges is therefore controlled by a balance between viscous compaction and melting rate, not by a change in melt topology. [ABSTRACT FROM AUTHOR]

The article presents a study that discusses the authors' proposed new adaptive technique that allows one to obtain cleaner normalized data. It mentions that the improved tomographic reconstruction is done using time-dependent intensity normalization. It is said to correct time-dependent phenomena that affect other tomographic imaging geometries such as X-ray computed tomography.

Background: Matrix metalloproteinases (MMPs) are well-known biological targets implicated in tumour progression, homeostatic regulation, innate immunity, impaired delivery of pro-apoptotic ligands, and the release and cleavage of cell-surface receptors. With this in mind, the perception of the intimate relationships among diverse MMPs could be a solid basis for accelerated learning in designing new selective MMP inhibitors. In this regard, decrypting the latent molecular reasons in order to elucidate similarity among MMPs is a key challenge. Results: We describe a pairwise variant of the non-parametric chaotic map clustering (CMC) algorithm and its application to 104 X-ray MMP structures. In this analysis electrostatic potentials are computed and used as input for the CMC algorithm. It was shown that differences between proteins reflect genuine variation of their electrostatic potentials. In addition, the analysis has been also extended to analyze the protein primary structures and the molecular shapes of the MMP co-crystallised ligands. Conclusions: The CMC algorithm was shown to be a valuable tool in knowledge acquisition and transfer from MMP structures. Based on the variation of electrostatic potentials, CMC was successful in analysing the MMP target family landscape and different subsites. The first investigation resulted in rational figure interpretation of both domain organization as well as of substrate specificity classifications. The second made it possible to distinguish the MMP classes, demonstrating the high specificity of the S1' pocket, to detect both the occurrence of punctual mutations of ionisable residues and different side-chain conformations that likely account for induced-fit phenomena. In addition, CMC demonstrated a potential comparable to the most popular UPGMA (Unweighted Pair Group Method with Arithmetic mean) method that, at present, represents a standard clustering bioinformatics approach. Interestingly, CMC and UPGMA resulted in closely comparable outcomes, but often CMC produced more informative and more easy interpretable dendrograms. Finally, CMC was successful for standard pairwise analysis (i.e., Smith-Waterman algorithm) of protein sequences and was used to convincingly explain the complementarity existing between the molecular shapes of the co-crystallised ligand molecules and the accessible MMP void volumes. [ABSTRACT FROM AUTHOR]