tom Why major automakers embrace Tesla's previously proprietary charging tech By www.npr.org Published On :: Tue, 12 Nov 2024 04:05:00 -0500 For a long time Tesla used its own kind of charger plug and had its own supercharger network. That once-exclusive network is opening up to other EV manufacturers. Full Article
tom What to know about Tom Homan, the former ICE head returning as Trump's 'border czar' By www.mprnews.org Published On :: Mon, 11 Nov 2024 16:10:00 +0000 Homan was the acting director of Immigration and Customs Enforcement from January 2017 to June 2018, where he was a key architect of the Trump administration's controversial family separation policy. Full Article
tom Trump taps former acting ICE director Tom Homan as 'border czar' By www.christianpost.com Published On :: Mon, 11 Nov 2024 13:11:25 -0500 President-elect Donald Trump announced that former acting director of U.S. Immigration and Customs Enforcement Tom Homan will serve as "border czar" in his new administration. Full Article
tom Workshop 8: Tom Perrotta By audioboom.com Published On :: Fri, 29 Jan 2016 16:16:39 -0000 Tom Perrotta is the author behind, among others, Little Children, The Abstinence Teacher, and The Leftovers, now a hit HBO drama which he co-writes. Recently, he provided the foreword to a new Penguin edition of The Scarlet Letter. We made a date with him and settled into a corner of Harvard Book Store to ask him about his writing process. #authors #books #writing Learn more about your ad choices. Visit podcastchoices.com/adchoices Full Article
tom Workshop 12: Tom Gjelten By audioboom.com Published On :: Wed, 09 Mar 2016 05:00:01 -0000 Long-time NPR reporter and five-time author Tom Gjelten recently visited the studios here at NHPR. We, of course, couldn't resist talking to him about his latest book, A Nation of Nations, and asking him for ten minutes. Learn more about your ad choices. Visit podcastchoices.com/adchoices Full Article
tom Workshop 14: Anatomical Historian Alice Dreger By audioboom.com Published On :: Wed, 06 Apr 2016 04:01:00 -0000 Alice Dreger is a historian of science, anatomy, and medicine, known for her work studying and advocating for people born with atypical sex disorders. She famously resigned from Northwestern University in protest of academic censorship, and gained some infamy on Twitter for live-tweeting her son's sex education class. We had a delightful chat with her about her writing process in advance of the paperback release of her book, Galileo's Middle Finger: Heretics, Activists, and the Search for Justice in Science. Learn more about your ad choices. Visit podcastchoices.com/adchoices Full Article
tom Workshop 32: Tom Gauld By audioboom.com Published On :: Wed, 30 Nov 2016 19:38:39 -0000 Tom Gauld -- a cartoonist, illustrator of comics and covers for the New Yorker and The Believer. His weekly cartoon about the arts for The Guardian newspaper is a wry, often deadpan favorite among writers. He is extremely prolific, author of more than a dozen books of comics, including You're Just Jealous of My Jetpack and most recently Mooncop. The lunar cop is perfectly Gauldian character - doesn't say much, spends a lot of time walking the barren landscape, is pretty lonesome and quaint. Virginia met with Tom before his talk at Harvard Book Store in Cambridge, Massachusetts, just an hour's drive from our studio. The challenge was finding a quiet spot to record in Harvard square...at rush hour. Music: "Feeding Pigeons" - Poddington Bear Ad Music: "Joy in the Restaurant" - David Szesztay Learn more about your ad choices. Visit podcastchoices.com/adchoices Full Article
tom Autism: Symptoms can be reversed in adulthood By english.pravda.ru Published On :: Mon, 22 Feb 2016 14:11:00 +0300 Autism: study published in "Nature" reveals that it is possible to reverse symptoms of the disease in adulthood - A team of American scientists and a Portuguese, Patricia Monteiro, investigated the SHANK3 gene, a gene implicated in autism, an incurable disease that affects about 70 million people worldwide. A study in which participated the Neurosciences and Cellular Biology Center (CNC), University of Coimbra (UC), published last week in the prestigious "Nature" *, reveals that it is possible to reverse some of the behaviors associated with autism in adulthood. SHANK3 gene under study A team of American scientists and a Portuguese, Patricia Monteiro, investigated the SHANK3 gene, a gene implicated in autism, an incurable disease that affects about 70 million people worldwide. In Portugal it is estimated that the prevalence of 1 case per 1,000 children of school age. In the USA, there has been a tenfold increase in the last 40 years. Full Article Health
tom USSR's Soyuz-11 disaster: 'Get some cognac ready for tomorrow!' By english.pravda.ru Published On :: Fri, 02 Jul 2021 15:02:00 +0300 June 30, 1971, was the day when the largest tragedy in the history of Soviet cosmonautics took place. It was the day, when the entire crew of the Soyuz-11 spacecraft was killed during the return mission: Georgy Dobrovolsky, Vladislav Volkov and Viktor Patsaev. When returning to Earth, the crew of the Soyuz-11 spacecraft - Vladislav Volkov, Georgy Dobrovolsky and Viktor Patsaev - were killed as a result of the depressurization of the descent vehicle. The cosmonauts were buried underneath the Kremlin wall. This was the second and the last disaster in the history of manned space flight for both the USSR and Russia. Soyuz comes to replace Gagarin's Vostok Soyuz is a family of disposable manned transport spacecraft, which was designed and built by Design Bureau OKB-1 (currently known as Energia Rocket and Space Corporation named after Korolev). Full Article History traditions
tom NATO's lost atomic bombs threaten the world By english.pravda.ru Published On :: Fri, 24 Dec 2021 19:35:00 +0300 According to international experts, the world has returned to the Cold War, but this time, the state of affairs is even more dramatic than it used to be. Airplanes with nuclear warheads on board are on duty again, like 30 years ago. The danger of such flights lies not only in the possible use of nuclear weapons. Nuclear bombs may go missing, as it had repeatedly happened in the past. Atomic bombs for Spain Several years ago, a Canadian diver, while diving into the sea near the Haida Gwaii archipelago, was horrified to find something that looked like an air nuclear bomb. The diver was right. In 1950, an American B-36 bomber was forced to jettison an atomic bomb into the Pacific Ocean due to a fire on board. Full Article History traditions
tom Zelensky's demand for Tomahawk missiles gives Washington jitters By english.pravda.ru Published On :: Thu, 31 Oct 2024 19:44:00 +0300 Volodymyr Zelensky's demand to transfer American Tomahawk missiles to Ukraine gave Washington the jitters, Russian Foreign Minister Sergey Lavrov said on the sidelines of the Minsk International Conference on Eurasian Security. "We know that his demand for Tomahawks caused bewilderment in Washington," Russian Foreign Minister Sergey Lavrov said. The Americans will "slap Zelensky on his hands" to ensure their security if he continues to try to drag them into the war against Russia, Lavrov noted. Full Article World
tom Waizu – Reducing mobile device loss and protecting the bottom line By www.retailtechnologyreview.com Published On :: RetailTechnologyReview.com spoke with Adrian Lawson, managing director of independent software vendor (ISV) Waizu, about how the company’s solutions are geared to helping organisations avoid the costly loss or misplacement of their mobile devices, thereby keeping their assets active and accountable and their workers fully productive. Full Article Data Capture Retail Supply Chain Mobile Computers
tom Customer adoption of Bitsight cloud monitoring grows 170% amid increased demand for Visibility Across digital infrastructure By www.retailtechnologyreview.com Published On :: Bitsight, the cyber risk management solutions provider, has introduced new asset mapping capabilities to help companies better manage vulnerabilities across their extended attack surface. Full Article Surveillance and Security Cloud Computing
tom H&M Russia staff say goodbye to customers in touching video By english.pravda.ru Published On :: Thu, 01 Dec 2022 18:41:00 +0300 H&M clothing, footwear and accessories store on Tverskaya Street in Moscow closed on November 30. An employee was filmed removing store banners and signs. A note to customers on a window says that the store is permanently closed, but all returns will be processed accordingly. The staff of H&M Russia recorded a video in which they say goodbye to customers. Full Article Business
tom Innovative retailers find new uses for RFID to boost their bottom line By www.retailtechnologyreview.com Published On :: A new research report has revealed the innovative new ways retailers are using RFID technology in-store to improve profitability. Full Article RFID Data Capture Critical Issues
tom Benefits of RFID in retail: Improved inventory management and happier customers By www.retailtechnologyreview.com Published On :: The use of RFID offers a whole range of advantages, two of which clearly stand out: precision and speed. DENSO explains what this means for the retail sector. Full Article RFID Data Capture
tom Retailers seek adaptable POS software to enhance customer experience By www.retailtechnologyreview.com Published On :: The number of POS software installations at major retail and hospitality operators worldwide surpassed 9 million as of June 2023, according to a new study from strategic research and consulting firm RBR Data Services, a division of Datos Insights. Full Article EPoS Systems Critical Issues
tom Integrating Advanced Software Solutions in Retail for Enhanced Customer Experience By www.retailtechnologyreview.com Published On :: By Jeremy Landau, freelance writer.Retail's dynamic environment is seeing a real shift, driven by the integration of advanced software solutions. This goes beyond a mere technological upgrade – it's about completely transforming the customer experience. Full Article EPoS Systems Internet Retailing Retail Supply Chain
tom Ergonomic Solutions: Delivering customer engagement at EuroCIS2024 By www.retailtechnologyreview.com Published On :: The retail industry is witnessing an unprecedented level of competition, and traditional marketing strategies are becoming obsolete.Recognizing the need for enabling innovative digital customer experiences, Ergonomic Solutions will showcase a comprehensive lineup of engaging customer facing solutions to drive personal interaction in retail and hospitality environments at EuroCIS 2024 (Hall 9 A40) in Dusseldorf from 27th – 29th February. Full Article Data Capture EPoS Systems Exhibitions and Events
tom Cleveron’s newest solution enables DIY and home furnishing retailers to automate their click-and-collect processes By www.retailtechnologyreview.com Published On :: Cleveron, a click-and-collect automation solutions innovator, is proud to launch a modular outdoor parcel locker, Cleveron 355. The newest solution is specially engineered for DIY and home furnishing retailers, enabling the automated handover of extra-large items. Full Article Data Capture Retail Supply Chain EPoS Systems
tom Data Fabric in Retail: The Go-To Solution to Boost Customer Experience and Personalization By www.retailtechnologyreview.com Published On :: By Jack Pollard, freelance writer.Retail is one of the most competitive landscapes out there today. Consumption is at an all-time high, but the cost of living crisis means that brands need to fight harder than ever to convince consumers that their products are what they need. Full Article Data Capture EPoS Systems Internet Retailing
tom KIOSK Information Systems Europe boosts business development and customer support with new staff By www.retailtechnologyreview.com Published On :: The Posiflex Group has responded to rising demand from customers in Europe by recruiting a seasoned executive to boost the European sales and marketing operations in its KIOSK subsidiary, a manufacturer of kiosks and interactive displays. Full Article Kiosk Technology
tom The Ergonomic Solutions Group’s new SpacePole Kiosk – A modular, configurable and customisable platform for a wide range of self-service applications By www.retailtechnologyreview.com Published On :: Tue, 13 Nov 4040 16:52:00 +0000 The Ergonomic Solutions Group, the designer and manufacturer of technology mounting solutions, has launched the SpacePole Kiosk – described as a multifunctional platform with maximum flexibility for a wide range of self-service applications including self-check-in/check-out, self-ordering, endless aisle, product display & advertising, ticketing, click & collect and many more. Full Article Kiosk Technology
tom Avantra showcases AI Innovation and automation leadership at SAP Sapphire Orlando and Barcelona By www.retailtechnologyreview.com Published On :: Mon, 13 Nov 4484 17:20:54 +0000 Avantra, provider of AIOps and automation solutions for SAP environments, was a prominent participant at the recent SAP Sapphire events held in Orlando and Barcelona. The company unveiled its latest AI capabilities and highlighted its pivotal role in enabling organizations to transition from manual operations to advanced automation. Full Article Data Capture Retail Supply Chain Exhibitions and Events
tom Make the Impossible Possible: Manhattan Showcases Latest Supply Chain Commerce Innovations and Customer Insights at Exchange 2024 By www.retailtechnologyreview.com Published On :: Building on the theme, ‘Make the impossible, possible’, Manhattan Associates has opened its annual EMEA Exchange event to an audience of more than 300 customers and press, with keynotes that introduced the European market to Manhattan Active Supply Chain Planning and Generative AI solutions; Manhattan Active Maven and Manhattan Assist. Full Article Retail Supply Chain Internet Retailing Exhibitions and Events
tom Overcome These 5 Customer Data Challenges in Retail with Cloud Solutions By www.retailtechnologyreview.com Published On :: By Franklin Carpenter, freelance writer.The importance of customer data in retail continues to grow, pushing businesses to seek efficient management strategies. Cloud computing has proven to be a powerful resource for tackling customer data challenges, enabling retailers to streamline their processes. Full Article Critical Issues Data Capture Internet Retailing Cloud Computing
tom Is Tomato Catsup the Same as Tomato Ketchup? By recipes.howstuffworks.com Published On :: Thu, 04 Apr 2024 16:03:19 -0400 In short, yes. Tomato-based catsup and ketchup are more or less the same condiment. There may be slight recipe variations on the traditional tomato-based version, but the main difference between ketchup and catsup is the alternative spelling of the same word. Full Article
tom Automated selection of nanoparticle models for small-angle X-ray scattering data analysis using machine learning By journals.iucr.org Published On :: 2024-02-29 Small-angle X-ray scattering (SAXS) is widely used to analyze the shape and size of nanoparticles in solution. A multitude of models, describing the SAXS intensity resulting from nanoparticles of various shapes, have been developed by the scientific community and are used for data analysis. Choosing the optimal model is a crucial step in data analysis, which can be difficult and time-consuming, especially for non-expert users. An algorithm is proposed, based on machine learning, representation learning and SAXS-specific preprocessing methods, which instantly selects the nanoparticle model best suited to describe SAXS data. The different algorithms compared are trained and evaluated on a simulated database. This database includes 75 000 scattering spectra from nine nanoparticle models, and realistically simulates two distinct device configurations. It will be made freely available to serve as a basis of comparison for future work. Deploying a universal solution for automatic nanoparticle model selection is a challenge made more difficult by the diversity of SAXS instruments and their flexible settings. The poor transferability of classification rules learned on one device configuration to another is highlighted. It is shown that training on several device configurations enables the algorithm to be generalized, without degrading performance compared with configuration-specific training. Finally, the classification algorithm is evaluated on a real data set obtained by performing SAXS experiments on nanoparticles for each of the instrumental configurations, which have been characterized by transmission electron microscopy. This data set, although very limited, allows estimation of the transferability of the classification rules learned on simulated data to real data. Full Article text
tom The single-atom R1: a new optimization method to solve crystal structures By journals.iucr.org Published On :: 2024-03-18 A crystal structure with N atoms in its unit cell can be solved starting from a model with atoms 1 to j − 1 being located. To locate the next atom j, the method uses a modified definition of the traditional R1 factor where its dependencies on the locations of atoms j + 1 to N are removed. This modified R1 is called the single-atom R1 (sR1), because the locations of atoms 1 to j − 1 in sR1 are the known parameters, and only the location of atom j is unknown. Finding the correct position of atom j translates thus into the optimization of the sR1 function, with respect to its fractional coordinates, xj, yj, zj. Using experimental data, it has been verified that an sR1 has a hole near each missing atom. Further, it has been verified that an algorithm based on sR1, hereby called the sR1 method, can solve crystal structures (with up to 156 non-hydrogen atoms in the unit cell). The strategy to carry out this calculation has also been optimized. The main feature of the sR1 method is that, starting from a single arbitrarily positioned atom, the structure is gradually revealed. With the user's help to delete poorly determined parts of the structure, the sR1 method can build the model to a high final quality. Thus, sR1 is a viable and useful tool for solving crystal structures. Full Article text
tom Integrating machine learning interatomic potentials with hybrid reverse Monte Carlo structure refinements in RMCProfile By journals.iucr.org Published On :: New software capabilities in RMCProfile allow researchers to study the structure of materials by combining machine learning interatomic potentials and reverse Monte Carlo. Full Article text
tom TOMOMAN: a software package for large-scale cryo-electron tomography data preprocessing, community data sharing and collaborative computing By journals.iucr.org Published On :: Here we describe TOMOMAN (TOMOgram MANager), an extensible open-sourced software package for handling cryo-electron tomography data preprocessing. TOMOMAN streamlines interoperability between a wide range of external packages and provides tools for project sharing and archival. Full Article text
tom Integrating machine learning interatomic potentials with hybrid reverse Monte Carlo structure refinements in RMCProfile By journals.iucr.org Published On :: 2024-10-29 Structure refinement with reverse Monte Carlo (RMC) is a powerful tool for interpreting experimental diffraction data. To ensure that the under-constrained RMC algorithm yields reasonable results, the hybrid RMC approach applies interatomic potentials to obtain solutions that are both physically sensible and in agreement with experiment. To expand the range of materials that can be studied with hybrid RMC, we have implemented a new interatomic potential constraint in RMCProfile that grants flexibility to apply potentials supported by the Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) molecular dynamics code. This includes machine learning interatomic potentials, which provide a pathway to applying hybrid RMC to materials without currently available interatomic potentials. To this end, we present a methodology to use RMC to train machine learning interatomic potentials for hybrid RMC applications. Full Article text
tom Deep learning to overcome Zernike phase-contrast nanoCT artifacts for automated micro-nano porosity segmentation in bone By journals.iucr.org Published On :: 2024-01-01 Bone material contains a hierarchical network of micro- and nano-cavities and channels, known as the lacuna-canalicular network (LCN), that is thought to play an important role in mechanobiology and turnover. The LCN comprises micrometer-sized lacunae, voids that house osteocytes, and submicrometer-sized canaliculi that connect bone cells. Characterization of this network in three dimensions is crucial for many bone studies. To quantify X-ray Zernike phase-contrast nanotomography data, deep learning is used to isolate and assess porosity in artifact-laden tomographies of zebrafish bones. A technical solution is proposed to overcome the halo and shade-off domains in order to reliably obtain the distribution and morphology of the LCN in the tomographic data. Convolutional neural network (CNN) models are utilized with increasing numbers of images, repeatedly validated by `error loss' and `accuracy' metrics. U-Net and Sensor3D CNN models were trained on data obtained from two different synchrotron Zernike phase-contrast transmission X-ray microscopes, the ANATOMIX beamline at SOLEIL (Paris, France) and the P05 beamline at PETRA III (Hamburg, Germany). The Sensor3D CNN model with a smaller batch size of 32 and a training data size of 70 images showed the best performance (accuracy 0.983 and error loss 0.032). The analysis procedures, validated by comparison with human-identified ground-truth images, correctly identified the voids within the bone matrix. This proposed approach may have further application to classify structures in volumetric images that contain non-linear artifacts that degrade image quality and hinder feature identification. Full Article text
tom Heitt Mjölnir: a heated miniature triaxial apparatus for 4D synchrotron microtomography By journals.iucr.org Published On :: 2024-01-01 Third- and fourth-generation synchrotron light sources with high fluxes and beam energies enable the use of innovative X-ray translucent experimental apparatus. These experimental devices access geologically relevant conditions whilst enabling in situ characterization using the spatial and temporal resolutions accessible at imaging beamlines. Here, Heitt Mjölnir is introduced, a heated miniature triaxial rig based on the design of Mjölnir, but covering a wider temperature range and larger sample volume at similar pressure capacities. This device is designed to investigate coupled thermal, chemical, hydraulic and mechanical processes from grain to centimetre scales using cylindrical samples of 10 mm × 20 mm (diameter × length). Heitt Mjölnir can simultaneously reach confining (hydraulic) pressures of 30 MPa and 500 MPa of axial stress with independently controlled sample pore fluid pressure < 30 MPa. This internally heated apparatus operates to temperatures up to 573 K with a minimal vertical thermal gradient in the sample of <0.3 K mm−1. This new apparatus has been deployed in operando studies at the TOMCAT (Swiss Light Source), I12 JEEP (Diamond Light Source) and PSICHÉ (Synchrotron SOLEIL) beamlines for 4D X-ray microtomography with scan intervals of a few minutes. Heitt Mjölnir is portable and modular, allowing a wide range of 4D characterizations of low-grade metamorphism and deformational processes. It enables spatially and temporally resolved fluid–rock interaction studies at conditions of crustal reservoirs and is suitable for characterization of material properties in geothermal, carbonation or subsurface gas storage applications. Technical drawings and an operation guide are included in this publication. Full Article text
tom Iterative Bragg peak removal on X-ray absorption spectra with automatic intensity correction By journals.iucr.org Published On :: 2024-04-09 This study introduces a novel iterative Bragg peak removal with automatic intensity correction (IBR-AIC) methodology for X-ray absorption spectroscopy (XAS), specifically addressing the challenge of Bragg peak interference in the analysis of crystalline materials. The approach integrates experimental adjustments and sophisticated post-processing, including an iterative algorithm for robust calculation of the scaling factor of the absorption coefficients and efficient elimination of the Bragg peaks, a common obstacle in accurately interpreting XAS data, particularly in crystalline samples. The method was thoroughly evaluated on dilute catalysts and thin films, with fluorescence mode and large-angle rotation. The results underscore the technique's effectiveness, adaptability and substantial potential in improving the precision of XAS data analysis. While demonstrating significant promise, the method does have limitations related to signal-to-noise ratio sensitivity and the necessity for meticulous angle selection during experimentation. Overall, IBR-AIC represents a significant advancement in XAS, offering a pragmatic solution to Bragg peak contamination challenges, thereby expanding the applications of XAS in understanding complex materials under diverse experimental conditions. Full Article text
tom First X-ray spectral ptychography and resonant ptychographic computed tomography experiments at the SWING beamline from Synchrotron SOLEIL By journals.iucr.org Published On :: 2024-05-21 X-ray ptychography and ptychographic computed tomography have seen a rapid rise since the advent of fourth-generation synchrotrons with a high degree of coherent radiation. In addition to quantitative multiscale structural analysis, ptychography with spectral capabilities has been developed, allowing for spatial-localized multiscale structural and spectral information of samples. The SWING beamline of Synchrotron SOLEIL has recently developed a nanoprobe setup where the endstation's first spectral and resonant ptychographic measurements have been successfully conducted. A metallic nickel wire sample was measured using 2D spectral ptychography in XANES mode and resonant ptychographic tomography. From the 2D spectral ptychography measurements, the spectra of the components of the sample's complex-valued refractive index, δ and β, were extracted, integrated along the sample thickness. By performing resonance ptychographic tomography at two photon energies, 3D maps of the refractive index decrement, δ, were obtained at the Ni K-edge energy and another energy above the edge. These maps allowed the detection of impurities in the Ni wire. The significance of accounting for the atomic scattering factor is demonstrated in the calculation of electron density near a resonance through the use of the δ values. These results indicate that at the SWING beamline it is possible to conduct state-of-the-art spectral and resonant ptychography experiments using the nanoprobe setup. Full Article text
tom 3D imaging of magnetic domains in Nd2Fe14B using scanning hard X-ray nanotomography By journals.iucr.org Published On :: 2024-05-21 Nanoscale structural and electronic heterogeneities are prevalent in condensed matter physics. Investigating these heterogeneities in 3D has become an important task for understanding material properties. To provide a tool to unravel the connection between nanoscale heterogeneity and macroscopic emergent properties in magnetic materials, scanning transmission X-ray microscopy (STXM) is combined with X-ray magnetic circular dichroism. A vector tomography algorithm has been developed to reconstruct the full 3D magnetic vector field without any prior noise assumptions or knowledge about the sample. Two tomographic scans around the vertical axis are acquired on single-crystalline Nd2Fe14B pillars tilted at two different angles, with 2D STXM projections recorded using a focused 120 nm X-ray beam with left and right circular polarization. Image alignment and iterative registration have been implemented based on the 2D STXM projections for the two tilts. Dichroic projections obtained from difference images are used for the tomographic reconstruction to obtain the 3D magnetization distribution at the nanoscale. Full Article text
tom Mapping of lithium ion concentrations in 3D structures through development of in situ correlative imaging of X-ray Compton scattering-computed tomography By journals.iucr.org Published On :: 2024-06-05 Understanding the correlation between chemical and microstructural properties is critical for unraveling the fundamental relationship between materials chemistry and physical structures that can benefit materials science and engineering. Here, we demonstrate novel in situ correlative imaging of the X-ray Compton scattering computed tomography (XCS-CT) technique for studying this fundamental relationship. XCS-CT can image light elements that do not usually exhibit strong signals using other X-ray characterization techniques. This paper describes the XCS-CT setup and data analysis method for calculating the valence electron momentum density and lithium-ion concentration, and provides two examples of spatially and temporally resolved chemical properties inside batteries in 3D. XCS-CT was applied to study two types of rechargeable lithium batteries in standard coin cell casings: (1) a lithium-ion battery containing a cathode of bespoke microstructure and liquid electrolyte, and (2) a solid-state battery containing a solid-polymer electrolyte. The XCS-CT technique is beneficial to a wide variety of materials and systems to map chemical composition changes in 3D structures. Full Article text
tom Self-calibration strategies for reducing systematic slope measurement errors of autocollimators in deflectometric profilometry By journals.iucr.org Published On :: 2024-06-05 Deflectometric profilometers are used to precisely measure the form of beam shaping optics of synchrotrons and X-ray free-electron lasers. They often utilize autocollimators which measure slope by evaluating the displacement of a reticle image on a detector. Based on our privileged access to the raw image data of an autocollimator, novel strategies to reduce the systematic measurement errors by using a set of overlapping images of the reticle obtained at different positions on the detector are discussed. It is demonstrated that imaging properties such as, for example, geometrical distortions and vignetting, can be extracted from this redundant set of images without recourse to external calibration facilities. This approach is based on the fact that the properties of the reticle itself do not change – all changes in the reticle image are due to the imaging process. Firstly, by combining interpolation and correlation, it is possible to determine the shift of a reticle image relative to a reference image with minimal error propagation. Secondly, the intensity of the reticle image is analysed as a function of its position on the CCD and a vignetting correction is calculated. Thirdly, the size of the reticle image is analysed as a function of its position and an imaging distortion correction is derived. It is demonstrated that, for different measurement ranges and aperture diameters of the autocollimator, reductions in the systematic errors of up to a factor of four to five can be achieved without recourse to external measurements. Full Article text
tom High-throughput and high-resolution powder X-ray diffractometer consisting of six sets of 2D CdTe detectors with variable sample-to-detector distance and innovative automation system By journals.iucr.org Published On :: 2024-06-20 The demand for powder X-ray diffraction analysis continues to increase in a variety of scientific fields, as the excellent beam quality of high-brightness synchrotron light sources enables the acquisition of high-quality measurement data with high intensity and angular resolution. Synchrotron powder diffraction has enabled the rapid measurement of many samples and various in situ/operando experiments in nonambient sample environments. To meet the demands for even higher throughput measurements using high-energy X-rays at SPring-8, a high-throughput and high-resolution powder diffraction system has been developed. This system is combined with six sets of two-dimensional (2D) CdTe detectors for high-energy X-rays, and various automation systems, including a system for automatic switching among large sample environmental equipment, have been developed in the third experimental hutch of the insertion device beamline BL13XU at SPring-8. In this diffractometer system, high-brilliance and high-energy X-rays ranging from 16 to 72 keV are available. The powder diffraction data measured under ambient and various nonambient conditions can be analysed using Rietveld refinement and the pair distribution function. Using the 2D CdTe detectors with variable sample-to-detector distance, three types of scan modes have been established: standard, single-step and high-resolution. A major feature is the ability to measure a whole powder pattern with millisecond resolution. Equally important, this system can measure powder diffraction data with high Q exceeding 30 Å−1 within several tens of seconds. This capability is expected to contribute significantly to new research avenues using machine learning and artificial intelligence by utilizing the large amount of data obtained from high-throughput measurements. Full Article text
tom X-ray phase-contrast tomography of cells manipulated with an optical stretcher By journals.iucr.org Published On :: 2024-06-11 X-rays can penetrate deeply into biological cells and thus allow for examination of their internal structures with high spatial resolution. In this study, X-ray phase-contrast imaging and tomography is combined with an X-ray-compatible optical stretcher and microfluidic sample delivery. Using this setup, individual cells can be kept in suspension while they are examined with the X-ray beam at a synchrotron. From the recorded holograms, 2D phase shift images that are proportional to the projected local electron density of the investigated cell can be calculated. From the tomographic reconstruction of multiple such projections the 3D electron density can be obtained. The cells can thus be studied in a hydrated or even living state, thus avoiding artifacts from freezing, drying or embedding, and can in principle also be subjected to different sample environments or mechanical strains. This combination of techniques is applied to living as well as fixed and stained NIH3T3 mouse fibroblasts and the effect of the beam energy on the phase shifts is investigated. Furthermore, a 3D algebraic reconstruction scheme and a dedicated mathematical description is used to follow the motion of the trapped cells in the optical stretcher for multiple rotations. Full Article text
tom Dual-beam X-ray nano-holotomography By journals.iucr.org Published On :: 2024-06-25 Nanotomography with hard X-rays is a widely used technique for high-resolution imaging, providing insights into the structure and composition of various materials. In recent years, tomographic approaches based on simultaneous illuminations of the same sample region from different angles by multiple beams have been developed at micrometre image resolution. Transferring these techniques to the nanoscale is challenging due to the loss in photon flux by focusing the X-ray beam. We present an approach for multi-beam nanotomography using a dual-beam Fresnel zone plate (dFZP) in a near-field holography setup. The dFZP generates two nano-focused beams that overlap in the sample plane, enabling the simultaneous acquisition of two projections from slightly different angles. This first proof-of-principle implementation of the dual-beam setup allows for the efficient removal of ring artifacts and noise using machine-learning approaches. The results open new possibilities for full-field multi-beam nanotomography and pave the way for future advancements in fast holotomography and artifact-reduction techniques. Full Article text
tom Automated spectrometer alignment via machine learning By journals.iucr.org Published On :: 2024-06-20 During beam time at a research facility, alignment and optimization of instrumentation, such as spectrometers, is a time-intensive task and often needs to be performed multiple times throughout the operation of an experiment. Despite the motorization of individual components, automated alignment solutions are not always available. In this study, a novel approach that combines optimisers with neural network surrogate models to significantly reduce the alignment overhead for a mobile soft X-ray spectrometer is proposed. Neural networks were trained exclusively using simulated ray-tracing data, and the disparity between experiment and simulation was obtained through parameter optimization. Real-time validation of this process was performed using experimental data collected at the beamline. The results demonstrate the ability to reduce alignment time from one hour to approximately five minutes. This method can also be generalized beyond spectrometers, for example, towards the alignment of optical elements at beamlines, making it applicable to a broad spectrum of research facilities. Full Article text
tom TomoPyUI: a user-friendly tool for rapid tomography alignment and reconstruction By journals.iucr.org Published On :: 2024-06-26 The management and processing of synchrotron and neutron computed tomography data can be a complex, labor-intensive and unstructured process. Users devote substantial time to both manually processing their data (i.e. organizing data/metadata, applying image filters etc.) and waiting for the computation of iterative alignment and reconstruction algorithms to finish. In this work, we present a solution to these problems: TomoPyUI, a user interface for the well known tomography data processing package TomoPy. This highly visual Python software package guides the user through the tomography processing pipeline from data import, preprocessing, alignment and finally to 3D volume reconstruction. The TomoPyUI systematic intermediate data and metadata storage system improves organization, and the inspection and manipulation tools (built within the application) help to avoid interrupted workflows. Notably, TomoPyUI operates entirely within a Jupyter environment. Herein, we provide a summary of these key features of TomoPyUI, along with an overview of the tomography processing pipeline, a discussion of the landscape of existing tomography processing software and the purpose of TomoPyUI, and a demonstration of its capabilities for real tomography data collected at SSRL beamline 6-2c. Full Article text
tom X-ray scattering based scanning tomography for imaging and structural characterization of cellulose in plants By journals.iucr.org Published On :: 2024-06-25 X-ray and neutron scattering have long been used for structural characterization of cellulose in plants. Due to averaging over the illuminated sample volume, these measurements traditionally overlooked the compositional and morphological heterogeneity within the sample. Here, a scanning tomographic imaging method is described, using contrast derived from the X-ray scattering intensity, for virtually sectioning the sample to reveal its internal structure at a resolution of a few micrometres. This method provides a means for retrieving the local scattering signal that corresponds to any voxel within the virtual section, enabling characterization of the local structure using traditional data-analysis methods. This is accomplished through tomographic reconstruction of the spatial distribution of a handful of mathematical components identified by non-negative matrix factorization from the large dataset of X-ray scattering intensity. Joint analysis of multiple datasets, to find similarity between voxels by clustering of the decomposed data, could help elucidate systematic differences between samples, such as those expected from genetic modifications, chemical treatments or fungal decay. The spatial distribution of the microfibril angle can also be analyzed, based on the tomographically reconstructed scattering intensity as a function of the azimuthal angle. Full Article text
tom Revealing the structure of the active sites for the electrocatalytic CO2 reduction to CO over Co single atom catalysts using operando XANES and machine learning By journals.iucr.org Published On :: 2024-06-25 Transition-metal nitrogen-doped carbons (TM-N-C) are emerging as a highly promising catalyst class for several important electrocatalytic processes, including the electrocatalytic CO2 reduction reaction (CO2RR). The unique local environment around the singly dispersed metal site in TM-N-C catalysts is likely to be responsible for their catalytic properties, which differ significantly from those of bulk or nanostructured catalysts. However, the identification of the actual working structure of the main active units in TM-N-C remains a challenging task due to the fluctional, dynamic nature of these catalysts, and scarcity of experimental techniques that could probe the structure of these materials under realistic working conditions. This issue is addressed in this work and the local atomistic and electronic structure of the metal site in a Co–N–C catalyst for CO2RR is investigated by employing time-resolved operando X-ray absorption spectroscopy (XAS) combined with advanced data analysis techniques. This multi-step approach, based on principal component analysis, spectral decomposition and supervised machine learning methods, allows the contributions of several co-existing species in the working Co–N–C catalysts to be decoupled, and their XAS spectra deciphered, paving the way for understanding the CO2RR mechanisms in the Co–N–C catalysts, and further optimization of this class of electrocatalytic systems. Full Article text
tom High-angular-sensitivity X-ray phase-contrast microtomography of soft tissue through a two-directional beam-tracking synchrotron set-up By journals.iucr.org Published On :: 2024-07-15 Two-directional beam-tracking (2DBT) is a method for phase-contrast imaging and tomography that uses an intensity modulator to structure the X-ray beam into an array of independent circular beamlets that are resolved by a high-resolution detector. It features isotropic spatial resolution, provides two-dimensional phase sensitivity, and enables the three-dimensional reconstructions of the refractive index decrement, δ, and the attenuation coefficient, μ. In this work, the angular sensitivity and the spatial resolution of 2DBT images in a synchrotron-based implementation is reported. In its best configuration, angular sensitivities of ∼20 nrad and spatial resolution of at least 6.25 µm in phase-contrast images were obtained. Exemplar application to the three-dimensional imaging of soft tissue samples, including a mouse liver and a decellularized porcine dermis, is also demonstrated. Full Article text
tom Hard X-ray imaging and tomography at the Biomedical Imaging and Therapy beamlines of Canadian Light Source By journals.iucr.org Published On :: 2024-07-15 The Biomedical Imaging and Therapy facility of the Canadian Light Source comprises two beamlines, which together cover a wide X-ray energy range from 13 keV up to 140 keV. The beamlines were designed with a focus on synchrotron applications in preclinical imaging and veterinary science as well as microbeam radiation therapy. While these remain a major part of the activities of both beamlines, a number of recent upgrades have enhanced the versatility and performance of the beamlines, particularly for high-resolution microtomography experiments. As a result, the user community has been quickly expanding to include researchers in advanced materials, batteries, fuel cells, agriculture, and environmental studies. This article summarizes the beam properties, describes the endstations together with the detector pool, and presents several application cases of the various X-ray imaging techniques available to users. Full Article text
tom BEATS: BEAmline for synchrotron X-ray microTomography at SESAME By journals.iucr.org Published On :: 2024-07-15 The ID10 beamline of the SESAME (Synchrotron-light for Experimental Science and Applications in the Middle East) synchrotron light source in Jordan was inaugurated in June 2023 and is now open to scientific users. The beamline, which was designed and installed within the European Horizon 2020 project BEAmline for Tomography at SESAME (BEATS), provides full-field X-ray radiography and microtomography imaging with monochromatic or polychromatic X-rays up to photon energies of 100 keV. The photon source generated by a 2.9 T wavelength shifter with variable gap, and a double-multilayer monochromator system allow versatile application for experiments requiring either an X-ray beam with high intensity and flux, and/or a partially spatial coherent beam for phase-contrast applications. Sample manipulation and X-ray detection systems are designed to allow scanning samples with different size, weight and material, providing image voxel sizes from 13 µm down to 0.33 µm. A state-of-the-art computing infrastructure for data collection, three-dimensional (3D) image reconstruction and data analysis allows the visualization and exploration of results online within a few seconds from the completion of a scan. Insights from 3D X-ray imaging are key to the investigation of specimens from archaeology and cultural heritage, biology and health sciences, materials science and engineering, earth, environmental sciences and more. Microtomography scans and preliminary results obtained at the beamline demonstrate that the new beamline ID10-BEATS expands significantly the range of scientific applications that can be targeted at SESAME. Full Article text
tom Investigating the missing-wedge problem in small-angle X-ray scattering tensor tomography across real and reciprocal space By journals.iucr.org Published On :: 2024-08-28 Small-angle-scattering tensor tomography is a technique for studying anisotropic nanostructures of millimetre-sized samples in a volume-resolved manner. It requires the acquisition of data through repeated tomographic rotations about an axis which is subjected to a series of tilts. The tilt that can be achieved with a typical setup is geometrically constrained, which leads to limits in the set of directions from which the different parts of the reciprocal space map can be probed. Here, we characterize the impact of this limitation on reconstructions in terms of the missing wedge problem of tomography, by treating the problem of tensor tomography as the reconstruction of a three-dimensional field of functions on the unit sphere, represented by a grid of Gaussian radial basis functions. We then devise an acquisition scheme to obtain complete data by remounting the sample, which we apply to a sample of human trabecular bone. Performing tensor tomographic reconstructions of limited data sets as well as the complete data set, we further investigate and validate the missing wedge problem by investigating reconstruction errors due to data incompleteness across both real and reciprocal space. Finally, we carry out an analysis of orientations and derived scalar quantities, to quantify the impact of this missing wedge problem on a typical tensor tomographic analysis. We conclude that the effects of data incompleteness are consistent with the predicted impact of the missing wedge problem, and that the impact on tensor tomographic analysis is appreciable but limited, especially if precautions are taken. In particular, there is only limited impact on the means and relative anisotropies of the reconstructed reciprocal space maps. Full Article text