Measurement of mass force field driving water refilling of cuttage

Cuttage is a common plant cultivation method, and the key to its survival is the restoration of water refilling, which remains unclear up to now. We report 3D dynamic imaging of water refilling of cuttage without resorting to any contrast agent. Hydrodynamics of the refilled water flow over time reveals the existence of a unit mass force field with a gradient along the refilling direction, which means that cutting plants also have a gradient force field to drive the recovery of water refilling, as predicted by Cohesion-Tension theory in normal plants. We found that force fields of different functional regions are isolated and independently distributed, which is conducive to ensure the safety of water transmission. At the same time, we also found that there is a so-called "inchworm effect" in the mass force field, which contributes to the force transfer inside the cutting through local force accumulation. Results of this paper demonstrate that the developed method for the measurement of mass force field in-vivo is applicable to help decipher the mechanism of plant water refilling.

Measurements regarding a combined therapy concept for ophthalmic tumors consisting of brachytherapy and x-rays

Objective We present a novel concept to treat ophthalmic tumors which combines brachytherapy and low-energy x-ray therapy. Brachytherapy with106Ru applicators applicators is inadequate for intraocular tumors with a height of 7 mm and more. This results from a steep dose gradient, and it is unfeasible to deliver the required dose at the tumor apex without exceeding the maximum tolerable sclera dose of usually 1000 to 1500 Gy. Other modalities, such as irradiation with charged particles, may be individually contraindicated. A dose boost at the apex provided by an x-ray therapy unit, performed simultaneously with the brachytherapy, results in a more homogeneous dose profile than brachytherapy alone. This avoids damage to organs at risk. The applicator may also serve as a beam stop for x-rays passing through the target volume, which reduces healthy tissue dosage. This study aims to investigate the suitability of the applicator to serve as a beam stop for the x-rays. Approach A phantom with three detector types comprising a soft x-ray ionization chamber, radiochromic films, and a self-made scintillation detector was constructed to perform dosimetry. Measurements were performed using a conventional x-ray unit for superficial therapy to investigate the uncertainties of the phantom and the ability of the applicator to absorb x-rays. The manufacturer provided a dummy plaque to obtain x-ray dose profiles without noise from106Ru decays. Results The phantom is generally feasible to obtain dose profiles with three different detector types. The interaction of x-rays with the silver of the applicator leads to an increased dose rate in front of the applicator. The dose rate of the x-rays is reduced by up to 90 % behind a106Ru applicator. Therefore, a106Ru applicator can be used as a beam stop in combined x-ray and brachytherapy treatment.

Structural maturation of myofilaments in engineered 3D cardiac microtissues characterized using small angle x-ray scattering

Understanding the structural and functional development of human-induced pluripotent stem-cell-derived cardiomyocytes (hiPSC-CMs) is essential to engineering cardiac tissue that enables pharmaceutical testing, modeling diseases, and designing therapies. Here we use a method not commonly applied to biological materials, small angle x-ray scattering, to characterize the structural development of hiPSC-CMs within three-dimensional engineered tissues during their preliminary stages of maturation. An x-ray scattering experimental method enables the reliable characterization of the cardiomyocyte myofilament spacing with maturation time. The myofilament lattice spacing monotonically decreases as the tissue matures from its initial post-seeding state over the span of 10 days. Visualization of the spacing at a grid of positions in the tissue provides an approach to characterizing the maturation and organization of cardiomyocyte myofilaments and has the potential to help elucidate mechanisms of pathophysiology, and disease progression, thereby stimulating new biological hypotheses in stem cell engineering.

X-ray dark-field computed tomography for monitoring of tissue freezing

Accurately monitoring the extent of freezing in biological tissue is an important requirement for cryoablation, a minimally invasive cancer treatment that induces cell death by freezing tissue with a cryoprobe. During the procedure, monitoring is required to avoid unnecessary harm to the surrounding healthy tissue and to ensure the tumor is properly encapsulated. One commonly used monitoring method is attenuation-based computed tomography (CT), which visualizes the ice ball by utilizing its hypoattenuating properties compared to unfrozen tissue. However, the contrast between frozen and unfrozen tissue remains low. In a proof-of-principle experiment, we show that the contrast between frozen and unfrozen parts of a porcine phantom mimicking breast tissue can be greatly enhanced by acquiring X-ray dark-field images that capture the increasing small-angle scattering caused by the ice crystals formed during the procedure. Our results show that, compared to X-ray attenuation, the frozen region is detected significantly better in dark-field radiographs and CT scans of the phantom. These findings demonstrate that X-ray dark-field imaging could be a potential candidate for improved monitoring of cryoablation procedures.

Quenched lattice fluctuations in optically driven SrTiO3

Crystal lattice fluctuations, which are known to influence phase transitions of quantum materials in equilibrium, are also expected to determine the dynamics of light-induced phase changes. However, they have only rarely been explored in these dynamical settings. Here we study the time evolution of lattice fluctuations in the quantum paraelectric SrTiO3, in which mid-infrared drives have been shown to induce a metastable ferroelectric state. Crucial in these physics is the competition between polar instabilities and antiferrodistortive rotations, which in equilibrium frustrate the formation of long-range ferroelectricity. We make use of high-intensity mid-infrared optical pulses to resonantly drive the Ti-O-stretching mode at 17 THz, and we measure the resulting change in lattice fluctuations using time-resolved X-ray diffuse scattering at a free-electron laser. After a prompt increase, we observe a long-lived quench in R-point antiferrodistortive lattice fluctuations. Their enhancement and reduction are theoretically explained by considering the fourth-order nonlinear phononic interactions to the driven optical phonon and third-order coupling to lattice strain, respectively. These observations provide a number of testable hypotheses for the physics of light-induced ferroelectricity.

Ultracompact mirror device for forming 20-nm achromatic soft-X-ray focus toward multimodal and multicolor nanoanalyses

Nanoscale soft-X-ray microscopy is a powerful analysis tool in biological, chemical, and physical sciences. To enhance its probe sensitivity and leverage multimodal soft-X-ray microscopy, precise achromatic focusing devices, which are challenging to fabricate, are essential. Here, we develop an ultracompact Kirkpatrick-Baez (ucKB) mirror, which is ideal for the high-performance nanofocusing of broadband-energy X-rays. We apply our advanced fabrication techniques and short-focal-length strategy to realize diffraction-limited focusing over the entire soft-X-ray range. We achieve a focus size of 20.4 nm at 2 keV, which represents a significant improvement in achromatic soft-X-ray focusing. The ucKB mirror extends soft-X-ray fluorescence microscopy by producing a bicolor nanoprobe with a 1- or 2-keV photon energy. We propose a subcellular chemical mapping method that allows a comprehensive analysis of specimen morphology and the distribution of light elements and metal elements. ucKB mirrors will improve soft-X-ray nanoanalyses by facilitating photon-hungry, multimodal, and polychromatic methods, even with table-top X-ray sources.

Nurse practitioners' use of diagnostic imaging: A scoping review

AIM

To explore the nature and extent of peer-reviewed literature related to the use of diagnostic imaging by nurse practitioners (NPs) to inform future practice and research.

BACKGROUND

Nurse practitioners undertake advanced assessment, diagnosis, and management of patients, including requesting and interpretation of diagnostic imaging. It is unclear what evidence exists related to the quality use of radiological investigations by NPs in recent years.

DESIGN

A scoping review based on the steps suggested by the Joanna Briggs Institute.

METHODS

A structured review of the databases Medline, CINAHL and Embase was undertaken using the keywords and MESH terms 'nurse practitioner', 'medical imaging', 'diagnostic imaging', 'scan' and 'radiography'. Only English language articles were included, and no date limit was applied. Database review was completed on 30 May 2021.

RESULTS

Eight themes were identified-country and clinical context, requesting diagnostic imaging, performing diagnostic imaging, image-guided interventions, interpreting diagnostic imaging, training education and knowledge, impact on resource usage and comparison with medical practitioners. There were more studies across a greater breadth of clinical specialties and imaging modalities in the United States than in other countries. Nurse practitioner practice is frequently benchmarked against that of medical colleagues. There is a paucity of studies focusing on educational preparation and the lack of relevant university curricula for NPs around diagnostic imaging.

CONCLUSION

There are significant gaps in the evidence outside of the United States across several of the identified themes. Further studies are needed to explore NP access to and use of diagnostic imaging and to understand the barriers and facilitators to this.

RELEVANCE TO CLINICAL PRACTICE

Studies from four countries were included in this review. The evidence suggests that, where studied, nurse practitioners (NPs) can safely and appropriately request and interpret plain x-rays in the emergency and minor injuries setting. Further research is needed to evaluate the educational needs of NPs in relation to diagnostic imaging and their use of advanced imaging techniques, particularly outside of the United States.

PATIENT OR PUBLIC CONTRIBUTION

No patient or public contribution.

Free-electron crystals for enhanced X-ray radiation

Bremsstrahlung-the spontaneous emission of broadband radiation from free electrons that are deflected by atomic nuclei-contributes to the majority of X-rays emitted from X-ray tubes and used in applications ranging from medical imaging to semiconductor chip inspection. Here, we show that the bremsstrahlung intensity can be enhanced significantly-by more than three orders of magnitude-through shaping the electron wavefunction to periodically overlap with atoms in crystalline materials. Furthermore, we show how to shape the bremsstrahlung X-ray emission pattern into arbitrary angular emission profiles for purposes such as unidirectionality and multi-directionality. Importantly, we find that these enhancements and shaped emission profiles cannot be attributed solely to the spatial overlap between the electron probability distribution and the atomic centers, as predicted by the paraxial and non-recoil theory for free electron light emission. Our work highlights an unprecedented regime of free electron light emission where electron waveshaping provides multi-dimensional control over practical radiation processes like bremsstrahlung. Our results pave the way towards greater versatility in table-top X-ray sources and improved fundamental understanding of quantum electron-light interactions.

Reconstruction of lateral coherence and 2D emittance in plasma betatron X-ray sources

X-ray sources have a strong social impact, being implemented for biomedical research, material and environmental sciences. Nowadays, compact and accessible sources are made using lasers. We report evidence of nontrivial spectral-angular correlations in a laser-driven betatron X-ray source. Furthermore, by angularly-resolved spectral measurements, we detect the signature of spatial phase modulations by the electron trajectories. This allows the lateral coherence function to be retrieved, leading to the evaluation of the coherence area of the source, determining its brightness. Finally, the proposed methodology allows the unprecedented reconstruction of the size of the X-ray source and the electron beam emittance in the two main emission planes in a single shot. This information will be of fundamental interest for user applications of new radiation sources.

Radiographic Robustness of Lumbar Interbody Fusion Techniques

STUDY DESIGN

Retrospective chart review.

OBJECTIVES

Lumbar interbody fusion (LIF) can be achieved with various techniques. Evidence supporting the long-term clinical advantages of one technique over another are inconclusive. The purpose of this study was to (1) determine the changes in sagittal parameters in the preoperative, intraoperative, and post-operative phase, (2) evaluate the radiographic maintenance of these parameters over time, and (3) compare the demographics and patient reported outcomes of patients undergoing various LIF techniques.

METHODS

We performed a retrospective chart review of patients with degenerative spine disease undergoing single level anterior (ALIF), lateral (LLIF), posterior (PLIF), or transforaminal (TLIF) lumbar interbody fusion. Data collected included patient demographics and diagnosis at time of surgery. Upright lumbar radiographs taken pre-operatively, intra-operatively, and post-operatively were measured for lumbar lordosis (LL), segmental lordosis (SL), posterior disc height (PDH), and foraminal height (FH).

RESULTS

194 patients in a single center were included. PDH and FH increased intra-operatively following ALIF (P < .0001), PLIF (P < .0001), LLIF (P < .0001), and TLIF (P < .0001). SL also increased intra-operatively for ALIF (P = .002) and LLIF (P = .0007). Compared to intra-operative radiographs, PDH and FH decreased at latest post-operative phase for ALIF (P < .03), LLIF (P < .003), TLIF (P < .001), and PLIF (P < .005). SL decreased for ALIF (P = .0008), and TLIF (P = .02). LL did not change postoperatively across techniques. Patient reported outcomes improved post-surgically and disability index decreased, but neither differed between techniques.

CONCLUSION

LIF, regardless of technique, was shown to provide significant radiographic changes in PDH and FH. Techniques utilizing larger intervertebral cage sizes (ALIF/LLIF) improved SL. Single level LIF did not affect overall LL. No single technique displayed superior radiographic robustness over time.

Highly efficient and aberration-free off-plane grating spectrometer and monochromator for EUV-soft X-ray applications

We demonstrate a novel flat-field, dual-optic imaging EUV-soft X-ray spectrometer and monochromator that attains an unprecedented throughput efficiency exceeding 60% by design, along with a superb spectral resolution of λ/Δλ > 200 accomplished without employing variable line spacing gratings. Exploiting the benefits of the conical diffraction geometry, the optical system is globally optimized in multidimensional parameter space to guarantee optimal imaging performance over a broad spectral range while maintaining circular and elliptical polarization states at the first, second, and third diffraction orders. Moreover, our analysis indicates minimal temporal dispersion, with pulse broadening confined within 80 fs tail-to-tail and an FWHM value of 29 fs, which enables ultrafast spectroscopic and pump-probe studies with femtosecond accuracy. Furthermore, the spectrometer can be effortlessly transformed into a monochromator spanning the EUV-soft X-ray spectral region using a single grating with an aberration-free spatial profile. Such capability allows coherent diffractive imaging applications to be conducted with highly monochromatic light in a broad spectral range and extended to the soft X-ray region with minimal photon loss, thus facilitating state-of-the-art imaging of intricate nano- and bio-systems, with a significantly enhanced spatiotemporal resolution, down to the nanometer-femtosecond level.

Ultrafast demagnetization in bulk nickel induced by X-ray photons tuned to Ni M3 and L3 absorption edges

Studies of light-induced demagnetization started with the experiment performed by Beaupaire et al. on Ni. Here, we present theoretical predictions for X-ray induced demagnetization of nickel, with X-ray photon energies tuned to its [Formula: see text] and [Formula: see text] absorption edges. We show that the specific feature in the density of states in the d-band of Ni, i.e., a sharp peak located just above the Fermi level, strongly influences the change of the predicted magnetic signal, making it stronger than in the previously studied case of X-ray demagnetized cobalt. It impacts also the value of Curie temperature for Ni. We believe that this finding will inspire dedicated experiments investigating magnetic processes in X-ray irradiated nickel and cobalt.

Ultrafast entropy production in pump-probe experiments

The ultrafast control of materials has opened the possibility to investigate non-equilibrium states of matter with striking properties, such as transient superconductivity and ferroelectricity, ultrafast magnetization and demagnetization, as well as Floquet engineering. The characterization of the ultrafast thermodynamic properties within the material is key for their control and design. Here, we develop the ultrafast stochastic thermodynamics for laser-excited phonons. We calculate the entropy production and heat absorbed from experimental data for single phonon modes of driven materials from time-resolved X-ray scattering experiments where the crystal is excited by a laser pulse. The spectral entropy production is calculated for SrTiO3 and KTaO3 for different temperatures and reveals a striking relation with the power spectrum of the displacement-displacement correlation function by inducing a broad peak beside the eigenmode-resonance.

Shape-Controlled Iron-Paraffin Composites as γ- and X-ray Shielding Materials Formable by Warmth-of-Hands-Derived Plasticity

The design of shielding materials against ionizing radiation while simultaneously displaying enhanced multifunctional characteristics remains challenging. Here, for the first time, we present moldable paraffin-based iron nano- and microcomposites attenuating γ- and X-radiation. The moldability was gained by the warmth-of-hands-driven plasticity, which allowed for obtaining a specific shape of the composites at room temperature. The manufactured composites contained iron particles of various sizes, ranging from 22 nm to 63 μm. The target materials were widely characterized using XRD, NMR, Raman, TGA, SEM, and EDX. In the case of microcomposites, the shielding properties were developed at two concentrations: 10 and 50 wt %. The statistically significant results indicate that the iron particle size has a negligible effect on the shielding properties of the nano- and microcomposites. On the other hand, the higher iron particle contents significantly affected the attenuating ability, which emerged even as superior to the elemental aluminum in the X-ray range: at a 70 kV anode voltage, the half value layer was 6.689, 1.882, and 0.462 cm for aluminum, paraffin + 10 wt % Fe 3.5-6.5 μm, and paraffin + 50 wt % Fe 3.5-6.5 μm microcomposites, respectively. Importantly, the elaborated methodology-in situ cross-verified in the hospital studies recording real-life sampling-opens the pathway to high-performance, eco-friendly, lightweight, and recyclable shields manufactured via fully reproducible and scalable protocols.

Evaluation of GPT-4's Chest X-Ray Impression Generation: A Reader Study on Performance and Perception

Exploring the generative capabilities of the multimodal GPT-4, our study uncovered significant differences between radiological assessments and automatic evaluation metrics for chest x-ray impression generation and revealed radiological bias.

Small-bore feeding tubes placed with an electromagnetic imaging device leads to cost avoidance and decreased time to initiation of enteral nutrition

BACKGROUND

The Cortrak Enteral Access System (CEAS) was previously approved by the United States Food and Drug Administration (FDA) to be used in lieu of radiographic confirmation imaging for feeding tubes placed by trained clinicians. Following an institutional protocol change in 2016, our registered dietitians had the option to forgo radiographic confirmation imaging for tubes placed using the CEAS. Our research aimed to determine the difference in the number of radiographic confirmation images for feeding tubes placed using the CEAS between preprotocol and postprotocol environments and the associated cost avoidance after the institutional policy change.

METHODS

We retrospectively reviewed data from 506 tube placements (n = 253 per protocol environment) in adult patients with diverse diagnoses admitted to various in-patient care units.

RESULTS

There was a significant reduction in the mean number of radiographic images per tube placement (preprotocol = 1.10 [95% CI, 1.05-1.15]; postprotocol = 0.36 [95% CI, 0.30-0.41]; P < 0.001), leading to a cost avoidance of $67,282.80 for the 253 tube placements and a potential cost avoidance of $279,236 over the 5-year postprotocol environment. Additionally, the mean time to initiation of enteral nutrition was significantly reduced by 2.65 h in the postprotocol environment (P < 0.001).

CONCLUSION

Our findings suggest that using the CEAS can reduce the number of radiographic images, provide cost avoidance, and improve nutrition outcomes. However, updated 2022 FDA regulatory changes to the use of the CEAS for tube confirmation lead to an uncertain future for this practice because of safety concerns.

Enhanced optical conductivity and many-body effects in strongly-driven photo-excited semi-metallic graphite

The excitation of quasi-particles near the extrema of the electronic band structure is a gateway to electronic phase transitions in condensed matter. In a many-body system, quasi-particle dynamics are strongly influenced by the electronic single-particle structure and have been extensively studied in the weak optical excitation regime. Yet, under strong optical excitation, where light fields coherently drive carriers, the dynamics of many-body interactions that can lead to new quantum phases remain largely unresolved. Here, we induce such a highly non-equilibrium many-body state through strong optical excitation of charge carriers near the van Hove singularity in graphite. We investigate the system's evolution into a strongly-driven photo-excited state with attosecond soft X-ray core-level spectroscopy. We find an enhancement of the optical conductivity of nearly ten times the quantum conductivity and pinpoint it to carrier excitations in flat bands. This interaction regime is robust against carrier-carrier interaction with coherent optical phonons acting as an attractive force reminiscent of superconductivity. The strongly-driven non-equilibrium state is markedly different from the single-particle structure and macroscopic conductivity and is a consequence of the non-adiabatic many-body state.

Prediction on X-ray output of free electron laser based on artificial neural networks

Knowledge of x-ray free electron lasers' (XFELs) pulse characteristics delivered to a sample is crucial for ensuring high-quality x-rays for scientific experiments. XFELs' self-amplified spontaneous emission process causes spatial and spectral variations in x-ray pulses entering a sample, which leads to measurement uncertainties for experiments relying on multiple XFEL pulses. Accurate in-situ measurements of x-ray wavefront and energy spectrum incident upon a sample poses challenges. Here we address this by developing a virtual diagnostics framework using an artificial neural network (ANN) to predict x-ray photon beam properties from electron beam properties. We recorded XFEL electron parameters while adjusting the accelerator's configurations and measured the resulting x-ray wavefront and energy spectrum shot-to-shot. Training the ANN with this data enables effective prediction of single-shot or average x-ray beam output based on XFEL undulator and electron parameters. This demonstrates the potential of utilizing ANNs for virtual diagnostics linking XFEL electron and photon beam properties.

XRF online analyzer for measurements of P2O5 content in phosphate slurry

Online X-ray Fluorescence (XRF) setup was constructed and optimized for analysing the P2O5 content in phosphate slurry (PS). Serval samples were analysed using two configurations of the setup, one with low and vertical flow and another with high and horizontal flow. The mean absolute error achieved through the first configuration was 0.87% and 0.38% using the second configuration. Reference samples were analyzed using the two configurations to construct the calibration curves. The curves cover a concentration range of P2O5 from 13.50 to 18.50% when considering the horizontal flow configuration, and a range of 14.00-15.60% when considering the vertical flow setup. An experimental study was conducted in order to optimize the measurement parameters for the online measurement of P2O5 in the phosphate slurry using the horizontal flow setup. A good signal-to-noise ratio (SNR) of [Formula: see text] was attained using an excitation energy of 20 kV or 25 kV, an excitation current of 600 µA, a distance of 18 mm between the sample and the detector, a measurement time of 60 s per spectrum and the use of an Aluminum filter between the X-ray tube and the measurement window. Online X-ray fluorescence analysis of P entails some challenges due to the low characteristic energy of P, the phosphate slurry matrix and the online analysis mode. However, the outcomes of this study indicate that XRF is a promising technology to meet the requirement for digitalization of chemical analysis of phosphate products.

Resonant X-ray excitation of the nuclear clock isomer 45Sc

Resonant oscillators with stable frequencies and large quality factors help us to keep track of time with high precision. Examples range from quartz crystal oscillators in wristwatches to atomic oscillators in atomic clocks, which are, at present, our most precise time measurement devices1. The search for more stable and convenient reference oscillators is continuing2-6. Nuclear oscillators are better than atomic oscillators because of their naturally higher quality factors and higher resilience against external perturbations7-9. One of the most promising cases is an ultra-narrow nuclear resonance transition in 45Sc between the ground state and the 12.4-keV isomeric state with a long lifetime of 0.47 s (ref. 10). The scientific potential of 45Sc was realized long ago, but applications require 45Sc resonant excitation, which in turn requires accelerator-driven, high-brightness X-ray sources11 that have become available only recently. Here we report on resonant X-ray excitation of the 45Sc isomeric state by irradiation of Sc-metal foil with 12.4-keV photon pulses from a state-of-the-art X-ray free-electron laser and subsequent detection of nuclear decay products. Simultaneously, the transition energy was determined as [Formula: see text] with an uncertainty that is two orders of magnitude smaller than the previously known values. These advancements enable the application of this isomer in extreme metrology, nuclear clock technology, ultra-high-precision spectroscopy and similar applications.

Water layer and radiation damage effects on the orientation recovery of proteins in single-particle imaging at an X-ray free-electron laser

The noise caused by sample heterogeneity (including sample solvent) has been identified as one of the determinant factors for a successful X-ray single-particle imaging experiment. It influences both the radiation damage process that occurs during illumination as well as the scattering patterns captured by the detector. Here, we investigate the impact of water layer thickness and radiation damage on orientation recovery from diffraction patterns of the nitrogenase iron protein. Orientation recovery is a critical step for single-particle imaging. It enables to sort a set of diffraction patterns scattered by identical particles placed at unknown orientations and assemble them into a 3D reciprocal space volume. The recovery quality is characterized by a "disconcurrence" metric. Our results show that while a water layer mitigates protein damage, the noise generated by the scattering from it can introduce challenges for orientation recovery and is anticipated to cause problems in the phase retrieval process to extract the desired protein structure. Compared to these disadvantageous effects due to the thick water layer, the effects of radiation damage on the orientation recovery are relatively small. Therefore, minimizing the amount of residual sample solvent should be considered a crucial step in improving the fidelity and resolution of X-ray single-particle imaging experiments.

X-ray dynamical diffraction by quasi-monolayer graphene

We study the processes of dynamical diffraction of the plane X-ray waves on the graphene film/SiC substrate system in the case of the Bragg diffraction geometry. The statistical dynamical theory of X-ray diffraction in imperfect crystals is applied to the case of real quasi-two-dimensional systems. The necessity of the taking into account of the variability of the lattice parameter of multilayer graphene, as well as the influence of thickness on the thermal Debye-Waller factor at the calculation of the complex structural factors and Fourier components of polarizability, is demonstrated. It is shown that the change of the structural characteristics of the 3-layer graphene/substrate system, as well as its strained state, leads to a significant change in the diffraction profiles, which makes it possible to determine the characteristics by the X-ray diffraction method.

Probing three-dimensional mesoscopic interfacial structures in a single view using multibeam X-ray coherent surface scattering and holography imaging

Visualizing surface-supported and buried planar mesoscale structures, such as nanoelectronics, ultrathin-film quantum dots, photovoltaics, and heterogeneous catalysts, often requires high-resolution X-ray imaging and scattering. Here, we discovered that multibeam scattering in grazing-incident reflection geometry is sensitive to three-dimensional (3D) structures in a single view, which is difficult in conventional scattering or imaging approaches. We developed a 3D finite-element-based multibeam-scattering analysis to decode the heterogeneous electric-field distribution and to faithfully reproduce the complex scattering and surface features. This approach further leads to the demonstration of hard-X-ray Lloyd's mirror interference of scattering waves, resembling dark-field, high-contrast surface holography under the grazing-angle scattering conditions. A first-principles calculation of the single-view holographic images resolves the surface patterns' 3D morphology with nanometer resolutions, which is critical for ultrafine nanocircuit metrology. The holographic method and simulations pave the way for single-shot structural characterization for visualizing irreversible and morphology-transforming physical and chemical processes in situ or operando.

Factors associated with poor prognosis of hip arthritis in juvenile idiopathic arthritis: Data from the JIR cohort

OBJECTIVES

Hip involvement remains a predictor of severe juvenile idiopathic arthritis (JIA) course and carries a high risk of disability. This study aims to determine the factors of poor prognosis of hip involvement in patients with JIA and to assess the treatment response.

METHODS

This is a multicenter observational cohort study. Patients were selected from the JIR Cohort database. Hip involvement was defined as clinically suspected and confirmed by an imaging tool. Follow-up data were collected during 5 years.

RESULTS

Among the 2223 patients with JIA, 341(15%) patients had hip arthritis. Male gender, enthesitis-related arthritis, and North African origin were factors associated with hip arthritis. Hip inflammation was associated with disease activity parameters during the first year, particularly Physician Global Assessment, joint count, and inflammatory marks. Structural hip progression was associated with early onset of the disease, a longer time to diagnosis, geographic origin, and JIA subtypes. Anti-TNF therapy was found to be the only treatment able to effectively reduce structural damage progression.

CONCLUSION

The early onset diagnostic delay, origin, and systemic subtype of JIA predict a poor prognosis of hip arthritis in children with JIA. The use of anti-TNF was associated with a better structural prognosis.

Generation of time-synchronized two-color X-ray free-electron laser pulses using phase shifters

To optimize the intensity of X-ray free-electron lasers (XFELs), phase shifters, oriented in phase with the phases of the XFEL pulse and electron beam, are typically installed at undulator lines. Although a π-offset between the phases (i.e., an "out-of-phase" configuration) can suppress the XFEL intensity at resonant frequencies, it can also generate a side-band spectrum, which results in a two-color XFEL pulse; the dynamics of such a pulse can be described using the spontaneous radiation or low gain theory. This attributes of this two-color XFEL pulse can be amplified (log-scale amplification) through an undulator line with out-of-phase phase shifters. In this study, the features of two-color XFEL pulses were evaluated through theory, simulations and experiments performed at Pohang Accelerator Laboratory X-ray Free Electron Laser. The XFEL gain slope and energy separation between the two-color spectral peaks were consistent through theoretical expectation, and the results of simulation and experiment. The experimentally determined two-color XFEL pulse energy was 250 μJ at a photon energy of 12.38 keV with a separation of 60 eV.

An X-ray free-electron laser with a highly configurable undulator and integrated chicanes for tailored pulse properties

X-ray free-electron lasers (FELs) are state-of-the-art scientific tools capable to study matter on the scale of atomic processes. Since the initial operation of X-ray FELs more than a decade ago, several facilities with upgraded performance have been put in operation. Here we present the first lasing results of Athos, the soft X-ray FEL beamline of SwissFEL at the Paul Scherrer Institute in Switzerland. Athos features an undulator layout based on short APPLE-X modules providing full polarisation control, interleaved with small magnetic chicanes. This versatile configuration allows for many operational modes, giving control over many FEL properties. We show, for example, a 35% reduction of the required undulator length to achieve FEL saturation with respect to standard undulator configurations. We also demonstrate the generation of more powerful pulses than the ones obtained in typical undulators. Athos represents a fundamental step forward in the design of FEL facilities, creating opportunities in FEL-based sciences.

Quantifying physical insights cooperatively with exhaustive search for Bayesian spectroscopy of X-ray photoelectron spectra

We analyzed the X-ray photoelectron spectra (XPS) of carbon 1s states in graphene and oxygen-intercalated graphene grown on SiC(0001) using Bayesian spectroscopy. To realize highly accurate spectral decomposition of the XPS spectra, we proposed a framework for discovering physical constraints from the absence of prior quantified physical knowledge, in which we designed the prior probabilities based on the found constraints and the physically required conditions. This suppresses the exchange of peak components during replica exchange Monte Carlo iterations and makes possible to decompose XPS in the case where a reliable structure model or a presumable number of components is not known. As a result, we have successfully decomposed XPS of one monolayer (1ML), two monolayers (2ML), and quasi-freestanding 2ML (qfs-2ML) graphene samples deposited on SiC substrates with the meV order precision of the binding energy, in which the posterior probability distributions of the binding energies were obtained distinguishably between the different components of buffer layer even though they are observed as hump and shoulder structures because of their overlapping.

Terabyte-scale supervised 3D training and benchmarking dataset of the mouse kidney

The performance of machine learning algorithms, when used for segmenting 3D biomedical images, does not reach the level expected based on results achieved with 2D photos. This may be explained by the comparative lack of high-volume, high-quality training datasets, which require state-of-the-art imaging facilities, domain experts for annotation and large computational and personal resources. The HR-Kidney dataset presented in this work bridges this gap by providing 1.7 TB of artefact-corrected synchrotron radiation-based X-ray phase-contrast microtomography images of whole mouse kidneys and validated segmentations of 33 729 glomeruli, which corresponds to a one to two orders of magnitude increase over currently available biomedical datasets. The image sets also contain the underlying raw data, threshold- and morphology-based semi-automatic segmentations of renal vasculature and uriniferous tubules, as well as true 3D manual annotations. We therewith provide a broad basis for the scientific community to build upon and expand in the fields of image processing, data augmentation and machine learning, in particular unsupervised and semi-supervised learning investigations, as well as transfer learning and generative adversarial networks.

Two-dimensional Kβ-Kα fluorescence spectrum by nonlinear resonant inelastic X-ray scattering

High sensitivity of the Kβ fluorescence spectrum to electronic state is widely used to investigate spin and oxidation state of first-row transition-metal compounds. However, the complex electronic structure results in overlapping spectral features, and the interpretation may be hampered by ambiguity in resolving the spectrum into components representing different electronic states. Here, we tackle this difficulty with a nonlinear resonant inelastic X-ray scattering (RIXS) scheme, where we leverage sequential two-photon absorption to realize an inverse process of the Kβ emission, and measure the successive Kα emission. The nonlinear RIXS reveals two-dimensional (2D) Kβ-Kα fluorescence spectrum of copper metal, leading to better understanding of the spectral feature. We isolate 3d-related satellite peaks in the 2D spectrum, and find good agreement with our multiplet ligand field calculation. Our work not only advances the fluorescence spectroscopy, but opens the door to extend RIXS into the nonlinear regime.

Reliability of assessing proximal femur geometry with Rutz classification schema in patients with cerebral palsy

Our investigation aimed to assess the reliability of the femoral head shape classification system devised by Rutz et al . and observe its application in patients with cerebral palsy (CP) at different skeletal maturity levels. Four independent observers assessed anteroposterior radiographs of the hips of 60 patients with hip dysplasia associated with non-ambulatory CP (Gross Motor Function Classification System levels IV and V) and recorded the femoral head shape radiological grading system as described by Rutz et al . Radiographs were obtained from 20 patients in each of three age groups: under 8 years, between 8 and 12 years and above 12 years old, respectively. Inter-observer reliability was assessed by comparing the measurements of four different observers. To determine the intra-observer reliability, radiographs were reassessed after a 4-week interval. Accuracy was checked by comparing these measurements with the assessment of expert consensus. Validity was checked indirectly by observing the relationship between the Rutz grade and the migration percentage. The Rutz classification system's evaluation of femoral head shape showed moderate to substantial intra- and inter-observer reliability (mean κ  = 0.64 for intraobserver and mean κ  = 0.5 for interobserver). Specialist assessors had slightly higher intra-observer reliability than trainee assessors. The grade of femoral head shape was significantly associated with increasing migration percentage. Rutz's classification was shown to be reliable. Once the clinical utility of this classification can be established, it has the potential for broad application for prognostication and surgical decision-making and as an essential radiographic variable in studies involving the outcomes of hip displacement in CP. Level of evidence: III.

Direct high-resolution X-ray imaging exploiting pseudorandomness

Owing to its unique penetrating power and high-resolution capability, X-ray imaging has been an irreplaceable tool since its discovery. Despite the significance, the resolution of X-ray imaging has largely been limited by the technical difficulties on X-ray lens making. Various lensless imaging methods have been proposed, but are yet relying on multiple measurements or additional constraints on measurements or samples. Here we present coherent speckle-correlation imaging (CSI) using a designed X-ray diffuser. CSI has no prerequisites for samples or measurements. Instead, from a single shot measurement, the complex sample field is retrieved based on the pseudorandomness of the speckle intensity pattern, ensured through a diffuser. We achieve a spatial resolution of 13.9 nm at 5.46 keV, beating the feature size of the diffuser used (300 nm). The high-resolution imaging capability is theoretically explained based on fundamental and practical limits. We expect the CSI to be a versatile tool for navigating the unexplored world of nanometer.

Detector-grade perovskite single-crystal wafers via stress-free gel-confined solution growth targeting high-resolution ionizing radiation detection

Solution-processed organic‒inorganic halide perovskite (OIHP) single crystals (SCs) have demonstrated great potential in ionizing radiation detection due to their outstanding charge transport properties and low-cost preparation. However, the energy resolution (ER) and stability of OIHP detectors still lag far behind those of melt-grown inorganic perovskite and commercial CdZnTe counterparts due to the absence of detector-grade high-quality OIHP SCs. Here, we reveal that the crystallinity and uniformity of OIHP SCs are drastically improved by relieving interfacial stress with a facial gel-confined solution growth strategy, thus enabling the direct preparation of large-area detector-grade SC wafers up to 4 cm with drastically suppressed electronic and ionic defects. The resultant radiation detectors show both a small dark current below 1 nA and excellent baseline stability of 4.0 × 10^-8nA cm^-1 s^-1 V^-1, which are rarely realized in OIHP detectors. Consequently, a record high ER of 4.9% at 59.5 keV is achieved under a standard ²⁴¹Am gamma-ray source with an ultralow operating bias of 5 V, representing the best gamma-ray spectroscopy performance among all solution-processed semiconductor radiation detectors ever reported.

Patient Radiation Doses Assessment at Diagnostic X-rays Department of King Khalid hospital (KKH)-Majmaah

BACKGROUND

The study was conducted on patients who received diagnostic X-rays in King Khalid Hospital (KKH), Majmaah.

INTRODUCTION

The study included the seven most frequently performed investigations, which were carried out on over 1504 patients using digital radiography equipment.

METHODS

The X-ray tube's output and exposure parameters were used to calculate the effective dose (ED) and patient entry surface air kerma (ESAK). Additionally, based on these results, conversion coefficients were determined. This study also examined the 75th percentile distributions of ESAK and KAP. The findings of this research were compared with the findings of other researchers throughout the country and the world. The study presents the uncertainty U values, as well as the mean ESAK, KAP, and ED values.

RESULTS

The results of the ESAK, KAP, and ED values were 0.12-5.74 mGy, 0.9-1.84 Gy cm2, and 0.01-0.23 mSv, respectively. As a result, the dosages were much lower than those previously published for the European DRL, national standards, and other studies.

CONCLUSION

The study concludes that during dose surveys, the importance of detecting and comprehending radiation doses, as well as the proper technique for taking the finest photos possible, can be emphasized to patients in order to assist them in avoiding radioactive particles and radiation exposure.

Viral inactivation by irradiation rays

Viral infection can lead to serious illness and death around the world, as exemplified by the spread of COVID-19. Using irradiation rays can inactive virions through ionizing and non-ionizing effect. The application of light in viral inactivation and the underlying mechanisms are reviewed by the research group of Dayong Jin from University of Technology Sydney.

Attosecond-Angstrom free-electron-laser towards the cold beam limit

Electron beam quality is paramount for X-ray pulse production in free-electron-lasers (FELs). State-of-the-art linear accelerators (linacs) can deliver multi-GeV electron beams with sufficient quality for hard X-ray-FELs, albeit requiring km-scale setups, whereas plasma-based accelerators can produce multi-GeV electron beams on metre-scale distances, and begin to reach beam qualities sufficient for EUV FELs. Here we show, that electron beams from plasma photocathodes many orders of magnitude brighter than state-of-the-art can be generated in plasma wakefield accelerators (PWFAs), and then extracted, captured, transported and injected into undulators without significant quality loss. These ultrabright, sub-femtosecond electron beams can drive hard X-FELs near the cold beam limit to generate coherent X-ray pulses of attosecond-Angstrom class, reaching saturation after only 10 metres of undulator. This plasma-X-FEL opens pathways for advanced photon science capabilities, such as unperturbed observation of electronic motion inside atoms at their natural time and length scale, and towards higher photon energies.

Self-aligned multi-layer X-ray absorption grating using large-area fabrication methods for X-ray phase-contrast imaging

X-ray phase-contrast (XPCi) imaging methods are an emerging medical imaging approach that provide significantly better soft tissue contrast and could function as a viable extension to conventional X-ray, CT, and even some MRI. Absorption gratings play a central role in grating-based XPCi systems, especially because they enable the acquisition of three images in a single exposure: transmission, refraction, and dark-field. An impediment to commercial development and adoption of XPCi imaging systems is the lack of large area, high aspect ratio absorption gratings. Grating technology development, primarily due to technological limitations, has lagged system development and today prevents the scaling up of XPCi system into a footprint and price point acceptable to the medical market. In this work, we report on a self-aligned multi-layer grating fabrication process that can enable large-area X-ray absorption gratings with micron-scale feature sizes. We leverage large-area fabrication techniques commonly employed by the thin-film transistor (TFT) display industry. Conventional ITO-on-glass substrates are used with a patterned film of Cr/Au/Cr that serves as a self-aligned lithography mask for backside exposure. Commonly available SU-8 photoresist is patterned using the backside exposure mask followed by an electroplating step to fill the gaps in the SU-8 with X-ray attenuating material. Consequently, the electroplated patterned material acts as a self-aligned photomask for subsequent SU-8 layer patterning and so forth. The repeatability of the reported process makes it suitable for achieving higher aspect ratio structures and is advantageous over previously reported X-ray LIGA approaches. A prototype three-layer grating, with a thickness of around [Formula: see text], having a visibility of 0.28 at [Formula: see text] with a [Formula: see text] active area was fabricated on a 4-inch glass substrate and demonstrated by modifying a commercially available 3D propagation-based XPCi Microscope. The scalable and cost-effective approach to build larger area X-ray gratings reported in this work can help expedite the commercial development and adoption of previously reported Talbot-Lau, speckle-tracking, as well as coded-aperture XPCi systems for large-area clinical and industrial applications.

Realizing nearly-zero dark current and ultrahigh signal-to-noise ratio perovskite X-ray detector and image array by dark-current-shunting strategy

Although perovskite X-ray detectors have revealed promising properties, their dark currents are usually hundreds of times larger than the practical requirements. Here, we report a detector architecture with a unique shunting electrode working as a blanking unit to suppress dark current, and it theoretically can be reduced to zero. We experimentally fabricate the dark-current-shunting X-ray detector, which exhibits a record-low dark current of 51.1 fA at 5 V mm^-1, a detection limit of 7.84 nGy_air s^-1, and a sensitivity of 1.3 × 10⁴ μC Gy_air^-1 cm^-2. The signal-to-noise ratio of our polycrystalline perovskite-based detector is even outperforming many previously reported state-of-the-art single crystal-based X-ray detectors by serval orders of magnitude. Finally, the proof-of-concept X-ray imaging of a 64 × 64 pixels dark-current-shunting detector array is successfully demonstrated. This work provides a device strategy to fundamentally reduce dark current and enhance the signal-to-noise ratio of X-ray detectors and photodetectors in general.

CT-based data generation for foreign object detection on a single X-ray projection

Although X-ray imaging is used routinely in industry for high-throughput product quality control, its capability to detect internal defects has strong limitations. The main challenge stems from the superposition of multiple object features within a single X-ray view. Deep Convolutional neural networks can be trained by annotated datasets of X-ray images to detect foreign objects in real-time. However, this approach depends heavily on the availability of a large amount of data, strongly hampering the viability of industrial use with high variability between batches of products. We present a computationally efficient, CT-based approach for creating artificial single-view X-ray data based on just a few physically CT-scanned objects. By algorithmically modifying the CT-volume, a large variety of training examples is obtained. Our results show that applying the generative model to a single CT-scanned object results in image analysis accuracy that would otherwise be achieved with scans of tens of real-world samples. Our methodology leads to a strong reduction in training data needed, improved coverage of the combinations of base and foreign objects, and extensive generalizability to additional features. Once trained on just a single CT-scanned object, the resulting deep neural network can detect foreign objects in real-time with high accuracy.

First measurement of energy diffusion in an electron beam due to quantum fluctuations in the undulator radiation

Plasma and beam physics are usually considered as classical physics disciplines with quantum effects featuring only rarely. In particular, free electron lasers (FELs) even in the Angstrom regime (developed recently and being upgraded towards even shorter wavelengths) are well described by classical mechanics and electrodynamics. There is, however, a quantum effect that can influence the operation of these devices and limit the shortest achievable wavelength, namely energy diffusion in an electron beam due to quantum fluctuations in undulator radiation. Although this effect has been calculated theoretically, it has never been measured. In this paper we present measurements of quantum diffusion effect at the European X-Ray Free-Electron Laser. The method uses a recently installed wakefield structure, which enables measurements of the longitudinal phase space after the hard X-ray undulator. The effect of quantum diffusion in the undulator is measured for the first time, and the results are in good agreement with theoretical predictions.

Spectral X-ray dark-field signal characterization from dual-energy projection phase-stepping data with a Talbot-Lau interferometer

Material-selective analysis of spectral X-ray imaging data requires prior knowledge of the energy dependence of the observed signal. Contrary to conventional X-ray imaging, where the material-specific attenuation coefficient is usually precisely known, the linear diffusion coefficient of the X-ray dark-field contrast does not only depend on the material and its microstructure, but also on the setup geometry and is difficult to access. Here, we present an optimization approach to retrieve the energy dependence of the X-ray dark-field signal quantitatively on the example of closed-cell foams from projection data without the need for additional hardware to a standard grating-based X-ray dark-field imaging setup. A model for the visibility is used to determine the linear diffusion coefficient with a least-squares optimization. The comparison of the results to spectrometer measurements of the linear diffusion coefficient suggests the proposed method to provide a good estimate for the energydependent dark-field signal.

Monochromatic computed tomography using laboratory-scale setup

In this article, we demonstrate the viability of highly monochromatic full-field X-ray absorption near edge structure based tomography using a laboratory-scale Johann-type X-ray absorption spectrometer utilising a conventional X-ray tube source. In this proof-of-concept, by using a phantom embedded with elemental Se, Na[Formula: see text]SeO[Formula: see text], and Na[Formula: see text]SeO[Formula: see text], we show that the three-dimensional distributions of Se in different oxidation states can be mapped and distinguished from the phantom matrix and each other with absorption edge contrast tomography. The presented method allows for volumetric analyses of chemical speciation in mm-scale samples using low-brilliance X-ray sources, and represents a new analytic tool for materials engineering and research in many fields including biology and chemistry.

Father and Son Jointly Announced the Discovery of Röntgen Rays in Two Consecutive Press Articles - Revisited

It is generally omitted that the press article announcing the discovery of Röntgen rays on the 5^th of January 1896 was followed by a second article published two days later in the same Viennese newspaper Die Presse under the same heading. While the initial article was composed hastily by the editor in a journalistic style and contained no information on the nature of the new rays, the second publication was partly composed by the son of the editor, a physicist, who informed on some of the basic physical properties of the Röntgen rays.

Artificial intelligence (AI) in restorative dentistry: Performance of AI models designed for detection of interproximal carious lesions on primary and permanent dentition

Objective

The objective of this study was to evaluate the effectiveness of deep learning methods in detecting dental caries from radiographic images.

Methods

A total of 771 bitewing radiographs were divided into two groups: adult (n = 554) and pediatric (n = 217). Two distinct semantic segmentation models were constructed for each group. They were manually labeled by general dentists for semantic segmentation. The inter-examiner reliability of the two examiners was also measured. Finally, the models were trained using transfer learning methodology along with computer science advanced tools, such as ensemble U-Nets with ResNet50, ResNext101, and Vgg19 as the encoders, which were all pretrained on ImageNet weights using a training dataset.

Results

Intersection over union (IoU) score was used to evaluate the outcomes of the deep learning model. For the adult dataset, the IoU averaged 98%, 23%, 19%, and 51% for zero, primary, moderate, and advanced carious lesions, respectively. For pediatric bitewings, the IoU averaged 97%, 8%, 17%, and 25% for zero, primary, moderate, and advanced caries, respectively. Advanced caries was more accurately detected than primary caries on adults and pediatric bitewings P < 0.05.

Conclusions

The proposed deep learning models can accurately detect advanced caries in permanent or primary bitewing radiographs. Misclassification mostly occurs between primary and moderate caries. Although the model performed well in correctly classifying the lesions, it can misclassify one as the other or does not accurately capture the depth of the lesion at this early stage.

Magnetic patterning of Co/Ni layered systems by plasma oxidation

We studied the structural, chemical, and magnetic properties of Ti/Au/Co/Ni layered systems subjected to plasma oxidation. The process results in the formation of NiO at the expense of metallic Ni, as clearly evidenced by X-ray photoelectron spectroscopy, while not affecting the surface roughness and grain size of the Co/Ni bilayers. Since the decrease of the thickness of the Ni layer and the formation of NiO increase the perpendicular magnetic anisotropy, oxidation may be locally applied for magnetic patterning. Using this approach, we created 2D heterostructures characterized by different combinations of magnetic properties in areas modified by plasma oxidation and in the regions protected from oxidation. As plasma oxidation is an easy to use, low cost, and commonly utilized technique in industrial applications, it may constitute an improvement over other magnetic patterning methods.

COVID-19 detection and classification for machine learning methods using human genomic data

Coronavirus is a disease connected to coronavirus. World Health Organization has declared COVID-19 a pandemic. It has an impact on 212 nations and territories worldwide. Examining and identifying patterns in X-Ray pictures of the lungs is still necessary. Early diagnosis may help to lessen a person's virus exposure and prevent it. Manual diagnosis is a time- and labor-intensive process. Since the COVID-19 virus has the potential to infect individuals all around the world, its finding is extremely concerning. The purpose of this study is to apply machine learning to identify and classify coronaviruses. The COVID-19 is anticipated to be discriminated and categorized in CT-Lung screening and computer-aided diagnosis (CAD). Several machine learning methods, including Decision Tree, Support Vector Machine, K-means clustering, and Radial Basis Function, were utilised in conjunction with clinical samples from patients who had contracted corona. While some medical professionals think an RT-PCR test is the most reliable and economical way to detect Covid-19 patients, others think a lung CT scan is more precise and less expensive. Serum samples, respiratory secretions, and whole blood samples are examples of clinical specimens. As a result of the earlier clinical evaluations, these tissues are used to assess 15 different parameters. As part of the proposed four-phase CAD system, the CT lungs screening collection is followed by a pre-processing step that enhances the appearance of ground-glass opacities (GGOs) nodules, which are initially extremely fuzzy and poorly contrasting due to the absence of contrast. These zones will be found and segmented using a modified K-means technique. Support vector machines (SVM) and radial basis functions (RBF) will be used as the input and target data for machine learning classifiers with a 50x50 pixel resolution to categorise the contaminated zones found during the detection phase (RBF). The 15 input items gathered from clinical specimens may be entered into a graphical user interface (GUI) tool that has been created to help doctors receive accurate findings.