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Zinc tungstate is a semiconductor known for its favorable photocatalytic, photoluminescence, and scintillation properties, coupled with its relatively low cost, reduced toxicity, and high stability in biological and catalytic environments. In particular, zinc tungstate evinces scintillation properties, namely the ability to emit visible light upon absorption of energetic radiation such as x rays, which has led to applications not only as radiation detectors but also for biomedical applications involving the delivery of optical light to deep tissue, such as photodynamic therapy and optogenetics. Here, we report on the synthesis of zinc tungstate nanorods generated via an optimized but facile method, which allows for synthetic control over the aspect ratio of the as-synthesized anisotropic motifs via rational variation of the solution pH. We investigate the effect of aspect ratio on their resulting photoluminescent and radioluminescent properties. We further demonstrate the potential of these zinc tungstate nanorods for biomedical applications, such as photodynamic therapy for cancer treatment, by analyzing their toxicological profile within cell lines and neurons. [ABSTRACT FROM AUTHOR]

The ability to visualize x-ray and neutron emission from fusion plasmas in 3D is critical to understand the origin of the complex shapes of the plasmas in experiments. Unfortunately, this remains challenging in experiments that study a fusion concept known as Magnetized Liner Inertial Fusion (MagLIF) due to a small number of available diagnostic views. Here, we present a basis function-expansion approach to reconstruct MagLIF stagnation plasmas from a sparse set of x-ray emission images. A set of natural basis functions is "learned" from training volumes containing quasi-helical structures whose projections are qualitatively similar to those observed in experimental images. Tests on several known volumes demonstrate that the learned basis outperforms both a cylindrical harmonic basis and a simple voxel basis with additional regularization, according to several metrics. Two-view reconstructions with the learned basis can estimate emission volumes to within 11% and those with three views recover morphology to a high degree of accuracy. The technique is applied to experimental data, producing the first 3D reconstruction of a MagLIF stagnation column from multiple views, providing additional indications of liner instabilities imprinting onto the emitting plasma. [ABSTRACT FROM AUTHOR]

The α-hydroxyethyl radical (CH3·CHOH, 2A) is a key intermediate in ethanol biochemistry, combustion, atmospheric chemistry, radiation chemistry, and astrochemistry. Experimental data on the vibrational spectrum of this radical are crucially important for reliable detection and understanding of the chemical dynamics of this species. This study represents the first detailed experimental report on the infrared absorption bands of the α-hydroxyethyl radical complemented by ab initio computations. The radical was generated in solid para-H2 and Xe matrices via the reactions of hydrogen atoms with matrix-isolated ethanol molecules and radiolysis of isolated ethanol molecules with x rays. The absorption bands with maxima at 3654.6, 3052.1, 1425.7, 1247.9, 1195.6 (1177.4), and 1048.4 cm−1, observed in para-H2 matrices appearing upon the H· atom reaction, were attributed to the OHstr, α-CHstr, CCstr, COstr + CCObend, COstr, and CCstr + CCObend vibrational modes of the CH3·CHOH radical, respectively. The absorption bands with the positions slightly red-shifted from those observed in para-H2 were detected in both the irradiated and post-irradiation annealed Xe matrices containing C2H5OH. The results of the experiments with the isotopically substituted ethanol molecules (CH3CD2OH and CD3CD2OH) and the quantum-chemical computations at the UCCSD(T)/L2a_3 level support the assignment. The photolysis with ultraviolet light (240–300 nm) results in the decay of the α-hydroxyethyl radical, yielding acetaldehyde and its isomer, vinyl alcohol. A comparison of the experimental and theoretical results suggests that the radical adopts the thermodynamically more stable anti-conformation in both matrices. [ABSTRACT FROM AUTHOR]

In this study, we observed natural methane (CH4) hydrate sediments, which are a type of unconventional natural gas resources, using x-ray computed tomography (CT). Because CH4 hydrates are formed by hydrogen bonding of water molecules with CH4, material decomposition becomes challenging when CH4 hydrates coexist with liquid or solid water in natural sediments. Tri-contrast (absorption, refraction, and scattering) imaging was performed via diffraction enhanced x-ray CT optics using monochromatic synchrotron x rays. The quantitative characterization of the contrast changes successfully enabled the decomposition of CH4 hydrates coexisting with frozen seawater (ice) in natural sediments obtained from the Okhotsk Sea. This study reveals complementary structural information about the microtexture and spatial relation among CH4 hydrates, ice, and pores by utilizing the distinct physical properties of x rays when passing through the materials. These results highlight the exceptional capabilities of high-resolution multicontrast x-ray tomography in materials science and geoscience applications. [ABSTRACT FROM AUTHOR]

Oblique shock wave–interface interactions of gases and liquids have been extensively studied in shock tubes using optical methods to measure equation-of-state (EOS) parameters. However, this is difficult with solids due to their opaqueness to visible light. X ray phase contrast imaging (XPCI) has the penetrative strength to probe solids while still being sensitive to mass density and enhancing the visibility of material boundaries. We investigate the accuracy and repeatability of measuring the mean value of the average mass density (areal density divided by thickness) over region S (B S) and flow deflection angle (θ) from XPCI images of a sample. To that end, a Hough transform-based method for measuring θ is developed. To measure B S , the XPCI image intensity probability density function (PDF) is modeled accounting for the spatial distribution of x ray energy, scintillator response, and pulse-to-pulse variation in the x ray intensity. In addition, a Monte Carlo-based algorithm for computing the B S PDF is developed. Both methods are validated on an impact-generated oblique shock wave interacting at a solid polymer-to-polymer interface. This is accomplished through a comparison to hydrodynamic simulations using well-established EOS. Under the modeling framework for the XPCI image intensity, B S is computed with an accuracy of < 0.1 % and precision of 3%–5%, while θ has an uncertainty of 0.2 ° , respectively. This shows that the XPCI-based model that is developed here could be an invaluable tool for high-fidelity testing of hydrodynamic models in shock polar configurations. [ABSTRACT FROM AUTHOR]

Millimeter-thick methylammonium lead tribromide (MAPbBr3) single crystal x-ray detectors have recently raised attention due to their high x-ray attenuation efficiency and good charge transport properties. However, an intriguing feature of the photocurrent response of MAPbBr3 detectors has been largely overlooked in the literature. After biasing, transient sensitivity is measured under x rays at short-circuit (bias = 0 V), thus revealing a large remnant electric field that builds up under bias. Here, we exploit the x-ray sensitivity of MAPbBr3 detectors at zero-bias in order to probe the internal built-in field, as well as to investigate the charge transport properties of the perovskite material. Our model derived from the Hecht equation is able to fully rationalize the response of the detectors both at short-circuit and under moderate applied bias. Moreover, we provide a method for the estimation of the internal electric field, and for the sum of the electrons and holes mobility–lifetime products μ e τ e + μ h τ h. This general method could extend to any perovskite-based x-ray detector exhibiting transient sensitivity at zero-bias. [ABSTRACT FROM AUTHOR]

We investigate the temporal correlation between very-high-frequency (VHF, at frequencies of the order of 10–100 MHz), ultrahigh-frequency (UHF, at frequencies within 1–6 GHz), and x-ray (with photon energies more than 10 keV) emissions, which accompany the development of a high-voltage discharge initiated in a long gap at voltages up to 1 MV. The x-ray and UHF emissions are found to emerge starting approximately from the prepulse current onset observed before the discharge gap breakdown and both gradually decay coming to this instant. The UHF emission spectrum is represented with frequencies up to 6 GHz, with the highest spectral power being achieved within 1–2 GHz. The radio emission power drops sharply at frequencies below 1 GHz and increases closer to 150 MHz with the highest spectral power of VHF radiation being reached within 60–90 MHz. The VHF emission can appear before the discharge current and UHF emission onsets in the form of 100-ns-long prepulses, and its intensity significantly increases as the UHF emission starts. The analysis of the temporal correlation between x rays, VHF, and UHF radiations, discharge current, and voltage waveforms indicates that the generation mechanisms of the discharge electromagnetic radiations are difficult to be interpreted in terms of the developing or colliding streamer concepts. [ABSTRACT FROM AUTHOR]

Three sets of heteroepitaxial diamond crystals grown under nominally identical process conditions on Ir/YSZ/Si(001) substrates have been studied with respect to structural defects, chemical purity, and x-ray induced photoconductivity (PC). The dislocation density that varied systematically between 10 7 and 10 9 cm − 2 had a minor influence on dark conductivity and photoconductive gain G. In contrast, the substitutional nitrogen (N N ) and substitutional boron (N B ) defects, which are both present at very low concentrations (≤ 1 ppb), turned out to be the crucial factors controlling the electrical behavior. Small differences between both resulted in variations of the photocurrents by up to 5 orders of magnitude. The maximum in G of 0.75 × 10 4 was measured in the sample with highest dark conductivity. It could be explained conclusively within our model calculations on gain formation by N N ≤ N B . For low gain samples, we found N N > --> N B . However, the measured G values were far from theoretical predictions. This indicates a dominating role of additional traps. After x-ray switch-off, persistent photoconductivity (PPC) was observed in high gain samples. It was attributed to an energetic barrier hampering the recharging of nitrogen atoms by hole capture. As a possible source, strain fields generated by dislocations are suggested. [ABSTRACT FROM AUTHOR]

The fragmentation of fulminic acid, HCNO, after excitation and ionization of core electrons was investigated using Auger-electron–photoion coincidence spectroscopy. A considerable degree of site-selectivity is observed. Ionization of the carbon and oxygen 1s electron leads to around 70% CH+ + NO+, while ionization at the central N-atom produces only 37% CH+ + NO+, but preferentially forms O+ + HCN+ and O+ + CN+. The mass-selected Auger-electron spectra show that these fragments are associated with higher binding energy final states. Furthermore, ionization of the C 1s electron leads to a higher propensity for C–H bond fission compared to O 1s ionization. Following resonant Auger–Meitner decay after 1s → 3π excitation, 12 different ionic products are formed. At the C 1s edge, the parent ion HCNO+ is significantly more stable compared to the other two edges, which we also attribute to the higher contribution of final states with low binding energies in the C 1s resonant Auger electron spectra. [ABSTRACT FROM AUTHOR]

The real contact area (RCA) of randomly rough contacts has received a great deal of attention because it correlates strongly with friction, lubrication, sealing, and conductivity. Simulations have revealed that the RCA associated with deterministic normal squeezing loads increases when tangential loads are also applied, in a phenomenon called junction growth. However, experimental investigations of the junction growth of randomly rough contacts are rare. Here, we used X-ray computed tomography (CT) to measure junction growth when two aluminum alloy surfaces were in contact. A high-resolution experimental setup was used to apply loads and observe contact behaviors at a resolution of 4 µm. The RCA and average contact gaps were computed using a three-dimensional (3D) geometric model constructed from gray CT images using the Otsu thresholding method. The results showed that the RCA increased as the normal load increased. The RCA increased by 22.67% after a tangential load was applied (junction growth), and the average gap decreased by 14.01% after a tangential load was applied. Thus, X-ray CT accurately measured the junction growth as a novel quantitative method. [ABSTRACT FROM AUTHOR]

In the past decade, deep learning in biomedical imaging has exponentially increased the accuracy of disease detection and improved the health standards. This research paper introduces a novel approach for the early detection and diagnosis of cardiomegaly using the cardiothoracic ratio (CT ratio) measurement in chest X-ray scans. Cardiomegaly is a serious cardiac condition that can lead to life-threatening complications if left undiagnosed. The proposed method involves segmenting the heart from a chest CT scan using a convolutional neural network model, ResNet-18, and calculating the CT ratio, which is the ratio of the maximum width of the heart to the maximum width of the thoracic cage. Studies have shown that increasing CT ratio leads to an increasing risk of heart diseases. Hence, a need to monitor the CT ratio for every individual arises, for if the ratio changes, an alert to take precautions can be rang. The method is evaluated using a dataset of 490 chest X-ray scans, and it achieves an accuracy of 80% and a precision of 84%. The integration of CT ratio measurement in chest X-ray scan reports has the potential to aid in the early detection and diagnosis of cardiomegaly, allowing for prompt medical intervention and improving patient outcomes. [ABSTRACT FROM AUTHOR]

Galaxy groups contain the majority of bound mass with a significant portion of baryons due to the combination of halo mass and abundance (Cui 2024). Hence they serve as a crucial missing piece in the puzzle of galaxy formation and the evolution of large-scale structures in the Universe. In observations, mass-complete group catalogues are normally derived from galaxy redshift surveys detected through various three-dimensional group-finding algorithms. Confirming the reality of such groups, particularly in the X-rays, is critical for ensuring robust studies of galaxy evolution in these environments. Recent works have reported numerous optical groups that are X-ray undetected (see, e.g. Popesso et al. 2024), sparking debates regarding the reasons for the unexpectedly low hot gas fraction in galaxy groups. To address this issue, we utilize zoomed-in simulations of galaxy groups from the novel Hyenas project to explore the range of hot gas fractions within galaxy groups and investigate the intrinsic factors behind the observed variability in X-ray emission. We find that the halo formation time can play a critical role–we see that groups in haloes that formed earlier exhibit up to an order of magnitude brighter X-ray luminosities compared to those formed later. This suggests that undetected X-ray groups are preferentially late-formed haloes and highlights the connection between gas fraction and halo formation time in galaxy groups. Accounting for these biases in galaxy group identification is essential for advancing our understanding of galaxy formation and achieving precision in cosmological studies. [ABSTRACT FROM AUTHOR]

A new bidentate bridging ligand, bis(2-pyridyl)thieno[3,4-b]pyrazine is reported, along with its mono- and bi-metallic Ru(II) complexes as representative examples. Spectroscopic, electrochemical and X-ray crystallographic characterization of these species is reported, with the separation of the two Ru(III)/Ru(II) couples of the bimetallic complex suggesting better metal–metal communication than classical polypyridyl analogues. [ABSTRACT FROM AUTHOR]

AT 2022cmc is a recently documented tidal disruption event that exhibits a luminous jet, accompanied by fast-declining X-ray and long-lasting radio and millimeter emission. Motivated by the distinct spectral and temporal signatures between the X-ray and radio observations, we propose a multizone model involving relativistic jets with different Lorentz factors. We systematically study the evolution of faster and slower jets in an external density profile, considering the continuous energy injection rate associated with time-dependent accretion rates before and after the mass fallback time. We investigate time-dependent multiwavelength emission from both the forward shock (FS) and reverse shock (RS) regions of the fast and slow jets, in a self-consistent manner. Our analysis demonstrates that the energy injection rate can significantly impact the jet evolution and subsequently influence the lightcurves. We find that the X-ray spectra and lightcurves could be described by electron synchrotron emission from the RS of the faster jet, in which the late-time X-ray upper limits, extending to 400 days after the disruption, could be interpreted as a jet break. Meanwhile, the radio observations can be interpreted as a result of synchrotron emission from the FS region of the slower jet. We also discuss prospects for testing the model with current and future observations. [ABSTRACT FROM AUTHOR]

While gamma-ray bursts (GRBs) have the potential to shed light on the astrophysics of jets, compact objects, and cosmology, a major set back in their use as probes of these phenomena stems from our incomplete knowledge surrounding their prompt emission. There are numerous models that can account for various observations of GRBs in the gamma-ray and X-ray energy ranges, due to the flexibility in the number of parameters that can be tuned to increase agreement with data. Furthermore, these models lack predictive power that can test future spectropolarimetric observations of GRBs across the electromagnetic spectrum. In this work, we use the MCRaT radiative transfer code to calculate the X-ray spectropolarimetric signatures expected from the photospheric model for two unique hydrodynamic simulations of long GRBs. We make time-resolved and time-integrated comparisons between the X-ray and gamma-ray mock observations, shedding light on the information that can be obtained from X-ray prompt emission signatures. Our results show that the T 90 derived from the X-ray light curve is the best diagnostic for the time that the central engine is active. We also find that our simulations reproduce the observed characteristics of the Einstein Probe–detected GRB 240315C. Based on our simulations, we are also able to make predictions for future X-ray spectropolarimetric measurements. Our results show the importance of conducting global radiative transfer calculations of GRB jets to better contextualize the prompt emission observations and constrain the mechanisms that produce the prompt emission. [ABSTRACT FROM AUTHOR]

The ultrashort and intense pulses of X-rays produced at X-ray free electron lasers (XFELs) have enabled unique experiments on the atomic level structure and dynamics of matter, with time-resolved studies permitted in the femto- and attosecond regimes. To fully exploit them, it is paramount to obtain a comprehensive understanding of the complex nonlinear interactions that can occur at such extreme X-ray intensities. Herein, we report on the experimental observation of a resonant double-core excitation scheme in N2, where two 1σ core-level electrons are resonantly promoted to unoccupied 1 π g * molecular orbitals by a single few-femtosecond broad-bandwidth XFEL pulse. The production of these neutral two-site double core hole states is evidenced through their characteristic decay channels, which are observed in good agreement with high-level theoretical calculations. Such multi-core excitation schemes, benefiting from the high interaction cross sections and state- and site-selective nature of resonant X-ray interactions, should be generally accessible in XFEL irradiated molecules, and provide interesting opportunities for chemical analysis and for monitoring ultrafast dynamic processes. XFELs can drive multicore-ionization/excitation processes in the fs timescale of typical core-hole lifetimes in molecules. This paper reports experimental evidence of a single XFEL-pulse-driven resonant double-core excitation mechanism, producing a neutral two-site double-core-hole state in the nitrogen molecule. [ABSTRACT FROM AUTHOR]

So-called "cross-docking" is the prediction of the bound configuration of small-molecule ligands that differ from the cognate ligand of a protein co-crystal structure. This is a much more challenging problem than re-docking the cognate ligand, particularly when the new ligand is structurally dissimilar from prior known ones. We have updated the previously introduced PINC ("PINC Is Not Cognate") benchmark which introduced the idea of temporal segregation to measure cross-docking performance. The temporal set encompasses 846 future ligands for ten targets based on information from the earliest 25% of X-ray co-crystal structures known for each target. Here, we extend the benchmark to include thirteen targets where the bound poses of 128 macrocyclic ligands are to be predicted based on knowledge from structures of bound non-macrocyclic ligands. Performance was roughly equivalent for both the temporally-split non-macrocyclic ligand set and the macrocycle prediction set. Using standard and fully automatic protocols for the Surflex-Dock and ForceGen methods, across the combined 974 non-macrocyclic and macrocyclic ligands, the top-scoring pose family was correct 68% of the time, with the top-two pose families achieving a 79% success rate. Correct poses among all those predicted were identified 92% of the time. These success rates far exceeded those observed for the alternative methods AutoDock Vina and Gnina on both sets. [ABSTRACT FROM AUTHOR]

Esophageal dysphagia is most commonly caused by motility disorders and intrinsic mechanical obstruction. However, extrinsic obstruction, such as pericardial effusion, is rare causes of dysphagia. We present an 89-year-old male with history of Waldenstrom macroglobulinemia, Charcot-Marie-Tooth syndrome, and basal cell carcinoma presenting with generalized weakness, productive cough, shortness of breath, and dysphagia to both solids and liquids. A chest X-ray obtained showed cardiomegaly with suggested central vascular congestion and pulmonary edema. Further imaging with computed tomography (CT) abdomen and pelvis showed a moderate-to-large pericardial effusion. Patient later developed signs and symptoms of cardiac tamponade, requiring urgent pericardiocentesis with removal of 1 L of sanguineous fluid. Up to today, only 6 cases of dysphagia due to pericardial effusion have been described. This case displays another rare case and highlights the importance of recognizing dysphagia as a critical symptom as well as non-gastrointestinal (GI) causes of dysphagia. [ABSTRACT FROM AUTHOR]

According to the World Health Organization (WHO), pneumonia kills about 2 million children under the age of 5 every year. Traditional machine learning methods can be used to diagnose chest X-rays of pneumonia in children, but there is a privacy and security issue in centralizing the data for training. Federated learning prevents data privacy leakage by sharing only the model and not the data, and it has a wide range of application in the medical field. We use federated learning method for classification, which effectively protects data security. And for the data heterogeneity phenomenon existing in the actual scenario, which will seriously affect the classification effect, we propose a method based on two-end control variables. Specifically, based on the classical federated learning FedAvg algorithm, we modify the loss function on the client side by adding a regular term or a penalty term, and add momentum after the average aggregation on the server side. The federated learning approach prevents the data privacy leakage problem compared to the traditional machine learning approach. In order to solve the problem of low classification accuracy due to data heterogeneity, our proposed method based on two-end control variables achieves an average improvement of 2% and an accuracy of 98% on average, and 99% individually, compared to the previous federated learning algorithms and the latest diffusion model-based method. The classification results and methodology of this study can be utilized by clinicians worldwide to improve the overall detection of pediatric pneumonia. [ABSTRACT FROM AUTHOR]

Pneumonia, a prevalent respiratory disease, affects millions globally. Accurate diagnosis and early detection are essential for managing and treating pneumonia. In recent years, machine learning and visual analysis technologies have shown promise for detecting pneumonia from therapeutic imageries such as chest X-rays. The dataset is collected from a Kaggle and contains X-ray scans of lungs from people of all ages. This dataset includes 5,856 labelled images, of which 4,273 are positive for pneumonia and 1,583 are negative. The data set is preprocessed using data augmentation techniques such as rotation, shifting, shearing, flipping and fill mode. The preprocessed data is trained using a masked neural network (MNN). The essential features are extracted from the last layer of MNN, and then the K-nearest neighbor (KNN) classify the chest X-rays to detect Pneumonia. This study developed a mask generation technique, dropout regularisation, and classifiers to train a model with 98.07% accuracy and minimal losses. This approach could lead to faster and more accurate pneumonia diagnoses, ultimately improving patient outcomes. Our research shows that transfer learning of KNN with MNN can effectively analyse chest X-rays to detect pneumonia. [ABSTRACT FROM AUTHOR]

Two complexes {[GdCu5(GlyHA)5(H2O)7Cr(C2O4)3]·11.02H2O}n (1) and {{[GdCu5(GlyHA)5(H2O)6]μ2-[Cu(C2O4)2(H2O)]}2μ4-[Cu(C2O4)2]·15.8H2O}n (2), were obtained as outcomes of the reactions between the cationic hexanuclear {GdCu5(GlyHA)5}3+ 15-metallacrown-5 complex (where GlyHA2− = glycinehydroxamate) and the anionic oxalate complexes K3[Cr(C2O4)3] or K2[Cu(C2O4)2]. Both 1 and 2 possess polymeric 1D-chain structures according to X-ray structural analysis. As a consequence of the geometric orientations of the donor atoms in the oxalates from [Cr(C2O4)3]3−, the Cu5 mean planes of neighboring 15-metallacrown-5 units {GdCu5(GlyHA)5}3+ are angled at 75.5° to each other, which leads to formation of a zig-zag motif in the 1D-chains of complex 1. The centrosymmetric complex 2 contains two structurally different bis(oxalato)cuprate anions μ2-[Cu(C2O4)2(H2O)]2−, for one of which, coordination to two adjacent {GdCu5(GlyHA)5}3+ units leads to formation of linear 1D-chains in 2, while the second type, μ4-[Cu(C2O4)2]2−, is coordinated to four {GdCu5(GlyHA)5}3+ units, causing the cross-linking of single 1D-chains into a double-chain 1D coordination polymer. Studies of χMT vs. T data for 1 and 2 in a 2–300 K temperature range revealed the presence of both ferromagnetic and antiferromagnetic interactions amongst paramagnetic centres. The experimental χMT vs. T data for 1 were fitted using a model which takes into account exchange interactions between adjacent copper(II) ions, the Gd–Cu exchange interactions within {GdCu5(GlyHA)5}3+ units and additionally Gd–Cr exchange interactions. Fitting of the χMT vs. T data for 2 was not possible, since coordination of μ4-[Cu(C2O4)2]2− to {GdCu5(GlyHA)5}3+ led to the non-equivalence of several Cu–Cu exchange interactions within the metallacrown units and hence a superfluity of fittable parameters. Complexes 1 and 2 are the first examples of 15-metallacrown-5 complexes demonstrating a magnetocaloric effect (−ΔSM at 13 T reaches 24.26 J K−1 kg−1 at 5 K and 19.14 J K−1 kg−1 at 4 K for 1 and 2, respectively). [ABSTRACT FROM AUTHOR]

Two-dimensional Cs2Pb(SCN)2I2 perovskite has an ultra-small interlayer spacing, inducing a series of interesting semiconductor properties, such as efficient interlayer carrier transport as well as lower exciton binding energy compared to perovskites with long alkylammonium cations. The prepared Cs2Pb(SCN)2I2 photodetector achieves a high on/off ratio of 2.1 × 104 with a specific detectivity of 6.2 × 1011 jones to 450 nm visible light, and a high sensitivity of 2747 μC Gyair−1 cm−2 to X-rays. [ABSTRACT FROM AUTHOR]

The segmentation accuracy of the lung images is affected by the occlusion of the front background objects. To address this problem, we propose a full-scale lung image segmentation algorithm based on hybrid skip connection and attention mechanism (HAFS). The algorithm uses yolov8 as the underlying network and enhancement of multi-layer feature fusion by incorporating dense and sparse skip connections into the network structure, and increased weighting of important features through attention gates. Finally the proposed algorithm was applied to the lung datasets Montgomery County chest X-ray and Shenzhen chest X-ray. The experimental results show that the proposed algorithm improves the precision, recall, pixel accuracy, Dice, mIoU, mAP and GFLOPs metrics compared to the comparison algorithms, which proves the advancement and effectiveness of the proposed algorithm. [ABSTRACT FROM AUTHOR]

Deep neural networks are increasingly used in medical imaging for tasks such as pathological classification, but they face challenges due to the scarcity of high-quality, expert-labeled training data. Recent efforts have utilized pre-trained contrastive image-text models like CLIP, adapting them for medical use by fine-tuning the model with chest X-ray images and corresponding reports for zero-shot pathology classification, thus eliminating the need for pathology-specific annotations. However, most studies continue to use the same contrastive learning objectives as in the general domain, overlooking the multi-labeled nature of medical image-report pairs. In this paper, we propose a new fine-tuning strategy that includes positive-pair loss relaxation and random sentence sampling. We aim to improve the performance of zero-shot pathology classification without relying on external knowledge. Our method can be applied to any pre-trained contrastive image-text encoder and easily transferred to out-of-domain datasets without further training, as it does not use external data. Our approach consistently improves overall zero-shot pathology classification across four chest X-ray datasets and three pre-trained models, with an average macro AUROC increase of 4.3%. Additionally, our method outperforms the state-of-the-art and marginally surpasses board-certified radiologists in zero-shot classification for the five competition pathologies in the CheXpert dataset. [ABSTRACT FROM AUTHOR]

Synchrotron emission from the shocked regions in supernova remnants provides, through its polarization, crucial details about the magnetic field strength and orientation in these regions. This, in turn, provides information on particle acceleration in these shocks. Due to the rapid losses of the highest-energy relativistic electrons, X-ray polarization measurements allow for investigations of the magnetic field to be carried outvery close to the sites of particle acceleration. Measurements of both the geometry of the field and the levels of turbulence implied by the observed polarization degree thus provide unique insights into the conditions leading to efficient particle acceleration in fast shocks. The Imaging X-ray Polarimetry Explorer (IXPE) has carried out observations of multiple young SNRs, including Cas A, Tycho, SN 1006, and RX J1713.7−3946. In each, significant X-ray polarization detections provide measurements of magnetic field properties that show some common behavior but also considerable differences between these SNRs. Here, we provide a summary of results from IXPE studies of young SNRs, providing comparisons between the observed polarization and the physical properties of the remnants and their environments. [ABSTRACT FROM AUTHOR]

Evidence-based radiographic guidelines are used to justify the need for radiographs and prevent their overuse. This study aimed to assess whether 4th-year chiropractic interns at the International Medical University plan to use x-ray imaging in their future private practice in line with the principles taught throughout their chiropractic program and the evidence-based imaging guidelines. A survey questionnaire was distributed to 74 final year chiropractic interns, with 62 completed responses. The questionnaire consisted of 8 case scenarios representing potential chiropractic patients. The interns were asked to decide whether to x-ray the patient or not, and which x-ray views to request if they chose to x-ray the patient. Results were compared with the gold standard using percentage agreement. The findings revealed that the chiropractic students adhered to the gold standard answers for 6 out of 8 cases. However, they did not perform well in selecting the correct x-ray views for the 3 cases where radiography was indicated by the gold standard. Results suggest that while the interns have a good understanding of when radiography is necessary, they may need additional training in selecting the appropriate x-ray views for each case. [ABSTRACT FROM AUTHOR]

Chest X-ray imaging is a critical diagnostic tool for identifying pulmonary diseases. However, manual interpretation of these images is time-consuming and error-prone. Automated systems utilizing convolutional neural networks (CNNs) have shown promise in improving the accuracy and efficiency of chest X-ray image classification. While previous work has mainly focused on using feature maps from the final convolution layer, there is a need to explore the benefits of leveraging additional layers for improved disease classification. Extracting robust features from limited medical image datasets remains a critical challenge. In this paper, we propose a novel deep learning-based multilayer multimodal fusion model that emphasizes extracting features from different layers and fusing them. Our disease detection model considers the discriminatory information captured by each layer. Furthermore, we propose the fusion of different-sized feature maps (FDSFM) module to effectively merge feature maps from diverse layers. The proposed model achieves a significantly higher accuracy of 97.21% and 99.60% for both three-class and two-class classifications, respectively. The proposed multilayer multimodal fusion model, along with the FDSFM module, holds promise for accurate disease classification and can also be extended to other disease classifications in chest X-ray images. [ABSTRACT FROM AUTHOR]

We systematically investigate the variability of polarized X-rays on a timescale of a few seconds in the low/hard state of the black hole binary Cygnus X-1. The correlation between polarization degrees and angles with X-ray intensity was analyzed using data collected by the Imaging X-ray Polarimetry Explorer (IXPE) in 2022 June. Given that X-ray variability in the low/hard state of Cygnus X-1 is non-periodic, flux peaks were aggregated to suppress statistical fluctuations. We divided the temporal profiles of these aggregated flux peaks into seven time segments and evaluated the polarization for each segment. The results reveal that the polarization degree was 4.6% |$\pm$| 1.2% and 5.3% |$\pm$| 1.2% before and after the peak, respectively, but decreased to 3.4% |$\pm$| 1.1% and 2.7% |$\pm$| 1.1% in the segments including and immediately following the peak. Furthermore, the polarization angle exhibited a slight shift from approximately 30 |$^{\circ }$| to |${\sim} 40^{\circ }$| before and after the peak. These findings suggest that the accretion disk contracts with increasing X-ray luminosity, and the closer proximity of the X-ray emitting gas to the black hole may lead to reduced polarization. [ABSTRACT FROM AUTHOR]

Background: Radiology, endoscopy, and clinical evaluation are the three most used diagnostic modalities for adenoids. This research aimed to evaluate the most accurate method for assessment of adenoid hypertrophy (radiological versus endoscopic Assessment). Patients and methods: We carried out this cross-sectional study on 60 children with chronic adenoid hypertrophy recruited from the ENT outpatient clinic in Zagazig university hospital for management their problem. During the initial assessment, a diagnostic nasal endoscopy was conducted utilizing both rigid and flexible endoscopes.X-ray nasopharynx lateral view was done for all patients. Results: By X ray 30% of the cases were Grade I, 31.7% were Grade II, 18.3% were Grade III and 20 % were Grade IV. By endoscope 30% of the cases were Grade I, 31.7% were Grade II, 28.3 were Grade III and 10% were Grade IV. Statistically significant agreements were revealed between the clinical grading and X ray (p<0.001), the clinical grading and endoscope (p=0.003), X ray and endoscope (p<0.001). Statistically significant positive correlation was found between grading by clinical examination and both X ray and endoscope (p<0.001). The sensitivity of X ray in diagnosis of the adenoid obstruction was 83.3%, specificity was 94.4%, PPV 62.5%, NPV 98% and Accuracy was 93.33% in comparison to endoscope as gold standard. Conclusion: The X-ray alone can rule out adenoidal hypertrophy, but alone it could be insufficient for assessment of the degree of adenoidal obstruction. Endoscopy was found to be more reliable, convenient, correlate well with the volume of adenoid tissue and allow estimation of adenoidal hypertrophy with degree of obstruction. This study demonstrates that combining clinical grading with endoscopy and radiology is important for the evaluation of adenoid hypertrophy. [ABSTRACT FROM AUTHOR]

Purpose: The study aims to establish the diagnostic accuracy of community spine x-rays for brace candidates. Methods: A review of adolescent idiopathic scoliosis patients seen for initial visit at a tertiary care pediatric hospital was conducted (n = 170). The index test was the pre-referral community spine x-ray interpreted by a community radiologist. Measures of diagnostic accuracy for the index test were determined against the reference standard if images were obtained within 90 days (n = 111). The reference standard was the 3-foot standing EOS spine x-ray evaluated by spine specialists. Diagnostic criterion for a brace candidate was dichotomized by Cobb angle range (25–40°) according to Scoliosis Research Society criteria. Risser stage was not included given significant missing data in index reports. To mitigate the uncertainty around true progression, sensitivity analyses were conducted on a sub-sample of data when index test was within 60 days of the reference standard (n = 67). Results: Accuracy of the community spine x-ray to detect a brace candidate was 65.8% (95% CI 56.2–74.5). Sensitivity of the index test was 65.4% with a false negative rate of 34.6%. Specificity was 66.1% with a false positive rate of 33.9%. Positive and negative predictive values were 63.0% and 68.4%, respectively. Of the total number of brace candidates (n = 52), 32.7% were missed because of underestimation in Cobb angle (95% CI 21.5–46.2). The proportion of missed brace candidates because of underestimation was unchanged with 60-day data (p = 0.37). Conclusions: Inaccuracies in community spine radiology may lead to missed opportunities for non-operative treatment. [ABSTRACT FROM AUTHOR]

This study examined the association between a dental implant and changes in adjacent teeth over time. Electronic health records of 1818 patients who received a dental implant were retrospectively evaluated over 14 years (2005–2019) in a university setting. The status of the adjacent tooth and vertical and horizontal distance from the implant platform to adjacent teeth were determined using digital intraoral radiographs taken at baseline and the last follow-up visit (1–14 years, median 4 years). In total, 1085 dental implants were evaluated. There were 234 instances of a change in the adjacent tooth. Decay was observed in 83 (7.6%) of adjacent teeth; the mean time to development was 4 years (range 1–14 years). Approximately 9% of adjacent teeth received direct restorations, 4.8% received indirect restorations, 1% received endodontic root canal treatment, and 5.6% were extracted. The mean horizontal distance between the implant platform and the adjacent teeth was 3.56 mm; the mean vertical distance from the contact point to the alveolar crest on the tooth side was 6.2 mm at the first time of the reported decay on X ray. These distances did not significantly influence the occurrence of caries. The prevalence of interproximal contact loss was higher on the mesial of the implant crown at 63% compared with 20% on the distal side. This large retrospective analysis identified that teeth adjacent to a dental implant were at risk of decay and changes in their condition. In addition, the implant-to-tooth distance and inadequate emergence profile may contribute as caries risk factors in addition to hygiene and a high sugar level diet. These findings appear essential for clinicians when making treatment decisions and discussing outcomes with patients. [ABSTRACT FROM AUTHOR]

We study $L^p$ -Sobolev regularity estimates for the restricted X-ray transforms generated by nondegenerate curves. Making use of the inductive strategy in the recent work by the authors, we establish the sharp $L^p$ -regularity estimates for the restricted X-ray transforms in $\mathbb {R}^{d+1}$ , $d\ge 3$. This extends the result due to Pramanik and Seeger in $\mathbb {R}^3$. [ABSTRACT FROM AUTHOR]

The influence of Si interlayers on the microstructure of the films and boundaries and on the reflective characteristics of Ti/Ni multilayer mirrors has been studied using X‐ray reflectometry and diffractometry. We established that these Si interlayers perform different functions at different interfaces. An Si interlayer at an Ni‐on‐Ti interface acts as a diffusion barrier. An Si interlayer at a Ti‐on‐Ni interface mainly acts as a smoothing layer with a slight diffusion barrier effect. The largest increase in the reflectance, from 62 to 65.7%, at a wavelength of 1.54 Å, is observed when Si interlayers are deposited on both boundaries. The reason for the increase in reflectivity is the decrease in the widths of the transition layers from 6.5 Å on Ni and 7.5 Å on Ti, to 6.0 Å on Ni and 5.0 Å on Ti, respectively. Here, we explain this through the 'barrier' effect of Si interlayers, which results in less mixing of film materials at the interfaces. Data on the reflectance of Ni/Ti multilayer mirrors in the spectral range of the 'water window' at a wavelength of 27.4 Å are presented for the first time. The maximum reflectivity for an Ni/Ti multilayer mirror at a grazing angle of 7.2° was about 56%. [ABSTRACT FROM AUTHOR]

Availability of pertinent and detailed information for damaged ancient objects is vital for successful restorative, damage limitation intervention processes in archeology. Visual inspection and radiography testing (RT) constitute widely used non-destructive methods for conservators of such objects. Unfortunately, the quality of RT images is susceptible to blurring caused by the superimposed scattered X-rays. In this study, the no-black-pixel constraint (NBPC) algorithm on its own as well as in the form of an algorithm with the planar-scene assumption (NBPC + PA) was applied to RT images with a view to suppressing image blurring and enhancement of imaging contrast. The results of this study have shown, both qualitatively and quantitatively that the NBPC + PA and NBPC algorithms provide higher imaging contrast for identification and evaluation of damage in corroded ancient metallic relics than using unprocessed RT images alone. Contrast enhancement of up to about 120% and 78% was achieved in comparison with the original image by applying the NBPC+PA and NBPC algorithms, respectively. Practical application and effectiveness of using the processed images were evaluated by expert operators in the area and it was found that using the reconstructed images scored higher (on average by 88%) than the original RT images (on average by 73%) with the NBPC+PA scoring higher (on average by 91%) than the NBPC algorithm (on average by 85%). The operators have found utilizing the processed images leads to better inspection and evaluation of the object enabling better targeted informed for restorative intervention, damage limitation, and maintenance of such objects. [ABSTRACT FROM AUTHOR]

In X-ray CT imaging, there are some cases where the obtained CT images have serious ring artifacts and noise, and these degraded CT images seriously affect the quality of clinical diagnosis. Thus, developing an effective method that can simultaneously suppress ring artifacts and noise is of great importance. Total variation (TV) is a famous prior regularization for image denoising in the image processing field, however, for degraded CT images, it can suppress the noise but fail to reduce the ring artifacts. To address this issue, the L 0 smoothing filter is incorporated with TV prior for CT ring artifacts and noise removal problem where the problem is transformed into several optimization sub-problems which are iteratively solved. The experiments demonstrate that the ring artifacts and noise presented in the CT image can be effectively suppressed by the proposed method and meanwhile the detailed features such as edge structure can be well preserved. As the superiority of TV and L 0 smoothing filters are fully utilized, the performance of the proposed method is better than the existing methods such as the TV-based method and L 0 -based method. [ABSTRACT FROM AUTHOR]

The article focuses on the use of point-of-care ultrasound (POCUS) for diagnosing a supracondylar humeral fracture in a 6-year-old girl with elbow pain after a fall. Topics include the child's initial presentation with limited elbow movement and tenderness, the role of POCUS in detecting fractures through the posterior fat pad sign and lipohemarthrosis, and confirmation of the diagnosis with radiographic imaging revealing a nondisplaced fracture.

Background: The straight and thin design of the CLS Spotorno stem makes it prone for coronal plane mal-alignment, with potential for cortical impingement; reactive osteogenesis and thigh pain have been documented in this situation with some stems. The literature is scarce about the effect of distal mal-alignment with this particular stem, and its relationship with thigh pain, functional outcomes and stem survival. We assessed functional outcomes with incidence of varus/valgus CLS stem alignment, and correlated stem subsidence of these thin stems with hip scores. Methodology: Hip arthroplasty cases with CLS Spotorno stems, operated between 2015 and 2022, with a minimum follow up of 18 months were evaluated. Radiology included 100% pelvis x-rays with bilateral hips (anteroposterior with 15° internal rotation plus lateral views); parameters documented were coronal mal-alignment, stem subsidence, any pedestal formation and heterotrophic ossification (HO); special note was made of any thigh pain, and functional outcomes were recorded using mHHS and SF-36 scores. Results: We evaluated 65 patients with 79 operated hips at an average follow up of 5.26 years. 31.6% (25/79) stems were neutrally aligned, 64.6% (51/79) were in varus alignment and 3.8% (3/79) were in valgus alignment. The mean subsidence was 3.15 mm + 2.26 and 3 cases had Pedestal formation at the stem tip. There was no correlation between varus/valgus stem positions with the mHHS (p = 0.271) and SF-36 score (p = 0.553), which also did not correlate with the stem subsidence. HO formation was seen in 16 hips (20.3%), but no cases in our series needed revision during follow up. Conclusion: Significant distal malalignment with some subsidence were noted in the hips studied; despite these radiological issues, there were excellent mid-term outcomes and good stems survival, implying that distal malposition may have no bearing on functional outcomes. [ABSTRACT FROM AUTHOR]

Particle crushing is a fundamental issue in the analysis of the deformation and failure behaviour of rockfill materials. The impact of morphology on the crushing behaviour of granite particles is investigated via a series of in-situ X-ray micro-CT tests and DEM simulations. Single-particle crushing tests are performed on rock particles of three different sizes. During mechanical loading, four in-situ CT scans are performed on each grain using an innovative loading apparatus. The CT test images reveal that the shape of the particle and its heterogeneous structure are crucial factors in determining failure patterns. Additionally, various shape indexes of rock particles change progressively and tend to stabilize, while their fragments follow a fractal distribution, seemingly independent of their initial size. Based on CT images, numerical particles with realistic shapes and internal flaws are generated using a proposed numerical method. It is observed that an increase in elongation index EI or flatness index FI results in a decrease in characteristic strength σ 0 and an increase in Weibull modulus m. Highlights: A novel loading apparatus has been developed for the realization of in-situ μ CT scans during single-particle crushing tests. CT test images reveal that particle shape and its heterogeneous structure are crucial factors in determining the failure pattern of rockfill particles. A new numerical method is proposed for generating particles, including both particle shape and microstructure. For particle shape, increasing the elongation index and flatness index of particle results in a decrease in characteristic strength σ 0 and an increase in Weibull modulus m. [ABSTRACT FROM AUTHOR]

The automated creation of medical reports from images of chest X-rays has the potential to significantly reduce workloads for healthcare providers and accelerate patient care, especially in environments with limited resources. This study provides an extensive overview of deep learning-based techniques designed for radiology report generation from chest X-ray pictures automatically. By examining recent research, we delve into various deep learning architectures and techniques used for this task, including transformer-based approaches, attention mechanisms, sequence-to-sequence models, adversarial training methods, and hybrid models. We also discuss about the datasets used for evaluation and training, as well as future directions and research problems in this area. The significance of deep learning in revolutionizing radiology reporting is further emphasized by our review, which also highlights the need for additional research to address challenges such data accessibility, image quality variability, interpretation of complex findings, and contextual integration. The objective of this research is to present a comparative analysis of cutting-edge methods for developing automated medical report generation to enhance patient outcomes and healthcare delivery. [ABSTRACT FROM AUTHOR]

Background: Digital image correlation (DIC) is widely used as a noncontact optical deformation measurement method. However, optical DIC encounters difficulties when measuring displacement and strain at high temperatures, including false deformation caused by heat haze and image overexposure caused by intense thermal radiation. X-ray imaging is not affected by these factors, so the combination of X-ray imaging and the DIC algorithm (X-DIC) holds the potential for measuring deformation during high-temperature tests. Objective: This study investigated the ability of X-DIC to measure deformation in high-temperature experiments, expand the applicable temperature range of X-DIC, and provide a reliable method for obtaining deformation measurements in high-temperature experiments. Methods: A combination of X-ray digital radiography (DR) images and the DIC algorithm was used to measure deformation. Numerical experiments based on synthetic images were used to evaluate the measurement accuracy of X-DIC, and the influence of different DIC parameters on the measurement error was discussed. Ductile iron and C/SiC composites were subjected to tensile tests at different temperatures from ambient temperature to 1000 °C, and different deformation measurement methods were used to simultaneously measure the deformation of the samples to verify the accuracy of the X-DIC results. Results: In the numerical experiments, the displacement measurement error of X-DIC is less than 0.02 px. The relative error between the X-DIC and blue-light DIC measurements of the tensile deformation of ductile iron at 500 °C is 0.65%. When the deformation of the C/SiC composite materials was measured at 1000 °C, the root mean square error (RMSE) of the strain data obtained by X-DIC and optical DIC was 1.12 × 10–4. Conclusions: These results prove that X-DIC has high measurement accuracy. Compared with optical DIC, X-DIC is insensitive to high-temperature environments and provides alternative experimental methods for high-temperature deformation measurements. [ABSTRACT FROM AUTHOR]

This paper presents a lightweight and accurate convolution neural network (CNN) based on encoder in vision transformer structure, which uses multigroup convolution rather than multilayer perceptron and multiheaded self-attention. We propose a group convolution block called multigroup convolution attention (MGCA) and squeeze and excitation (SE). The MGCA includes two parts: three 1 × 1 convolutions concatenated along the channel dimension and depth-wise separable convolution. SE is used as a skip connection to provide long-range dependencies. MGCA-SE is introduced to reduce the number of parameters in state-of-the-art network in order to use fewer datasets for training CNN. Furthermore, we provide a lightweight network based on MGCA-SE in Resnet architecture called Resnet-multigroup convolution attention-squeeze and excitation (Res-MGCA-SE) in order to have early detection and treatment of medical images. Finally, Res-MGCA-SE is evaluated on lung cancer and Covid-19 chest X-ray and CT and images. According to our research findings, MGCA-SE can change convolutional layers in state-of-the-art networks and switch them to lightweight networks with properties comparable to heavy-weight networks. [ABSTRACT FROM AUTHOR]

Proton therapy gives less dose to healthy tissue compared to conventional X-ray therapy, but systematic comparisons of normal tissue responses are lacking. The aim of this study was to investigate late tissue responses in the salivary glands following proton- or X-irradiation of the head and neck in mice. Moreover, we aimed at investigating molecular responses by monitoring the cytokine levels in serum and saliva. Female C57BL/6J mice underwent local fractionated irradiation with protons or X-rays to the maximally tolerated acute level. Saliva and serum were collected before and at different time points after irradiation to assess salivary gland function and cytokine expression. To study late responses in the major salivary glands, histological analyses were performed on tissues collected at day 105 after onset of irradiation. Saliva volume after proton and X-irradiation was significantly lower than for controls and remained reduced at all time points after irradiation. Protons caused reduced saliva production and fewer acinar cells in the submandibular glands compared to X-rays at day 105. X-rays induced a stronger inflammatory cytokine response in saliva compared to protons. This work supports previous preclinical findings and indicate that the relative biological effectiveness of protons in normal tissue might be higher than the commonly used value of 1.1. [ABSTRACT FROM AUTHOR]

A superbubble is a hot, dilute, and X-ray-emitting gas cavity produced by stellar winds and supernova explosions. It is an intriguing feature for the study of stellar feedback processes. We report a study of possible superbubbles in the Andromeda Galaxy (M31). We identify one out of 83 extended sources as a strong superbubble candidate, SB1, from the M31 X-ray source catalogue. SB1 is located in the northern disc of M31 and exhibits soft, extended X-ray emission surrounded by an Hα shell. The XMM–Newton spectral analysis reveals that SB1 has a temperature of ∼0.14 keV and an X-ray luminosity of |$L_{\rm X}\sim 3.5\times 10^{37}\,{\rm erg\, s}^{-1}$| in the 0.3–10.0 keV band. Two stellar clusters are found at the west rim of SB1. The estimated age of SB1 is similar to that of an overlapping young stellar cluster, and the colour-magnitude diagram reveals the presence of young stellar objects with an age of less than 10 Myr. We propose that SB1 is a superbubble, likely having triggered star formation in this cluster by compressing the accumulated gas, thereby leading to the formation of gas-dense regions. [ABSTRACT FROM AUTHOR]

Self-supervised learning methods for medical images primarily rely on the imaging modality during pretraining. Although such approaches deliver promising results, they do not take advantage of the associated patient or scan information collected within Electronic Health Records (EHR). This study aims to develop a multimodal pretraining approach for chest radiographs that considers EHR data incorporation as an additional modality that during training. We propose to incorporate EHR data during self-supervised pretraining with a Masked Siamese Network (MSN) to enhance the quality of chest radiograph representations. We investigate three types of EHR data, including demographic, scan metadata, and inpatient stay information. We evaluate the multimodal MSN on three publicly available chest X-ray datasets, MIMIC-CXR, CheXpert, and NIH-14, using two vision transformer (ViT) backbones, specifically ViT-Tiny and ViT-Small. In assessing the quality of the representations through linear evaluation, our proposed method demonstrates significant improvement compared to vanilla MSN and state-of-the-art self-supervised learning baselines. In particular, our proposed method achieves an improvement of of 2% in the Area Under the Receiver Operating Characteristic Curve (AUROC) compared to vanilla MSN and 5% to 8% compared to other baselines, including uni-modal ones. Furthermore, our findings reveal that demographic features provide the most significant performance improvement. Our work highlights the potential of EHR-enhanced self-supervised pretraining for medical imaging and opens opportunities for future research to address limitations in existing representation learning methods for other medical imaging modalities, such as neuro-, ophthalmic, and sonar imaging. [ABSTRACT FROM AUTHOR]

A new one-dimensional hybrid [APCHA]Cu2I4 was designed and applied as an X-ray scintillator. It exhibits broad-band green emission with a high PLQY of 74.80% and excellent stability. It demonstrates radioluminescence property with a light yield of 28 336 photons MeV−1, detection limit of 41 nGyair s−1, and high spatial limit of 13.95 lp mm−1 in X-ray imaging. [ABSTRACT FROM AUTHOR]

Background: Several studies have advocated the use of ultrasound to diagnose distal forearm fractures in children. However, there is limited data on the diagnostic accuracy of ultrasound for distal forearm fractures when conducted by pediatric surgeons or trainees who manage orthopedic injuries in children. The objective of this study was to determine the diagnostic accuracy of point-of-care ultrasound (POCUS) for pediatric distal forearm fractures when conducted by pediatric surgeons and trainees after minimal training. Methods: This diagnostic study was conducted in a tertiary hospital emergency department in Germany. Participants were children and adolescents under 15 years of age who presented to the emergency department with an acute, suspected, isolated distal forearm fracture requiring imaging. Pediatric surgeons and trainees, after minimal training for sonographic fracture diagnosis, performed 6-view distal forearm POCUS on each participant prior to X-ray imaging. All data was retrospectively collected from the hospital's routine digital patient files. The primary outcome was the diagnostic accuracy of POCUS compared to X-ray as the reference standard. Results: From February to June 2021, 146 children under 15 met all inclusion and exclusion criteria, and 106 data sets were available for analysis. Regarding the presence of a fracture, X-ray and Wrist-POCUS showed the same result in 99.1%, with 83/106 (78.3%) fractures detected in both modalities and one suspected buckle fracture on POCUS not confirmed in the radiographs. Wrist-POCUS had a sensitivity of 100% (95% CI [0.956, 1]) and a specificity of 95.8% (95% CI [0.789, 0.999]) compared to radiographs. In 6 cases, there were minor differences regarding a concomitant ulnar buckle. The amount of prior ultrasound training had no influence on the accuracy of Wrist-POCUS for diagnosing distal forearm fractures. All fractures were reliably diagnosed even when captured POCUS images did not meet all quality criteria. Conclusion: Pediatric surgeons and trainees, after minimal training in POCUS, had excellent diagnostic accuracy for distal forearm fractures in children and adolescents using POCUS compared to X-ray. [ABSTRACT FROM AUTHOR]

Methylfluoride and hydrogen fluoride react with powerful methylating agent [SO2Me]+ in a temperature-dependent addition reaction to form methylated fluorosulfuric acid [FS(OMe)2][Sb2F11] and methylated fluorosulfuric acid methyl ester [FS(OH)(OMe)][SbF6], respectively. The obtained methylated fluorosulfinic acid and methylated fluorosulfinic acid methyl ester were characterized by single X-ray structure analysis and vibrational spectroscopy. [ABSTRACT FROM AUTHOR]

Several medical consultations and examinations have been undertaken online since the Covid outbreak. However, when private data was communicated over the internet or uploaded to the cloud, medical information became more susceptible to security risks. Steganography is a technique that can be used to hide sensitive information within a cover image. This paper presents four improved algorithms to enhance steganography's performance in medical images. A full-size hidden image that is as huge as a cover image cannot be handled by previous methods, which is what the algorithmic design is meant to address. Several creative methods are presented, including the computation of Discrete Cosine Transform (DCT) coefficients based on scaled floating values, the addition of an adaptive compression matrix, and a new approach for systematically dispersing a concealed number of bits across multiple separate locations in the cover image. The results of the experiment showed a notable advancement over the earlier research. Our secret image size is substantially larger than the past studies, yet the structure similarity index matrix (SSIM) of the best reconstructed secret image is close to ideal, the peak signal-to-noise ratio (PSNR) and the payload capacity are higher than in the previous studies. This research is beneficial since it contributes to a medical application for enhancing the security of information concealed in chest X-ray images. Medical personnel can generate an image that conceals patient information in a secure manner. [ABSTRACT FROM AUTHOR]

To release medical images that can be freely used in downstream processes while maintaining their utility, it is necessary to remove personal features from the images while preserving the lesion structures. Unlike previous studies that focused on removing lesion structures while preserving the individuality of medical images, this study proposes and validates a new framework that maintains the lesion structures while diffusing individual characteristics. In this framework, we apply local differential privacy techniques to provide theoretical guarantees of privacy protection. Additionally, to enhance the utility of protected medical images, we perform denoising using a diffusion model on the noise-contaminated medical images. Numerous chest X-rays generated by the proposed method were evaluated by physicians, revealing a trade-off between the level of privacy protection and utility. In other words, it was confirmed that increasing the level of personal information protection tends to result in relatively lower utility. This study potentially enables the release of certain types of medical images that were previously difficult to share. [ABSTRACT FROM AUTHOR]