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We present an analysis of the first two XRISM/Resolve spectra of the well-known Seyfert-1.5 active galactic nucleus (AGN) in NGC 4151, obtained in 2023 December. Our work focuses on the nature of the narrow Fe K _α emission line at 6.4 keV, the strongest and most common X-ray line observed in AGN. The total line is found to consist of three components. Even the narrowest component of the line is resolved with evident Fe K _α _,1 (6.404 keV) and K _α _,2 (6.391 keV) contributions in a 2:1 flux ratio, fully consistent with neutral gas with negligible bulk velocity. Subject to the limitations of our models, the narrowest and intermediate-width components are consistent with emission from optically thin gas, suggesting that they arise in a disk atmosphere and/or wind. Modeling the three line components in terms of Keplerian broadening, they are readily associated with (1) the inner wall of the “torus,” (2) the innermost optical “broad-line region” (or “X-ray BLR”), and (3) a region with a radius of r ≃ 100 GM / c ^2 that may signal a warp in the accretion disk. Viable alternative explanations of the broadest component include a fast-wind component and/or scattering; however, we find evidence of variability in the narrow Fe K _α line complex on timescales consistent with small radii. The best-fit models are statistically superior to simple Voigt functions, but when fit with Voigt profiles the time-averaged lines are consistent with a projected velocity broadening of FWHM $\,=\,{1600}_{-200}^{+400}\,\mathrm{km}\,{{\rm{s}}}^{-1}$ . Overall, the resolution and sensitivity of XRISM show that the narrow Fe K line in AGN is an effective probe of all key parts of the accretion flow, as it is currently understood. We discuss the implications of these findings for our understanding of AGN accretion, future studies with XRISM, and X-ray-based black hole mass measurements.

Abstract X-ray CT scanners, due to the transmissive nature of X-rays, have enabled the non-destructive evaluation of industrial products, even inside their bodies. In light of its effectiveness, this study introduces a new approach to accelerate the inspection of many mechanical parts with the same shape in a bin. The input to this problem is a volumetric image (i.e., CT volume) of many parts obtained by a single CT scan. We need to segment the parts in the volume to inspect each of them; however, random postures and dense contacts of the parts prohibit part segmentation using traditional template matching. To address this problem, we convert both the scanned volumetric images of the template and the binned parts to simpler graph structures and solve a subgraph matching problem to segment the parts. We perform a distance transform to convert the CT volume into a distance field. Then, we construct a graph based on Morse theory, in which graph nodes are located at the extremum points of the distance field. The experimental evaluation demonstrates that our fully automatic approach can detect target parts appropriately, even for a heap of 50 parts. Moreover, the overall computation can be performed in approximately 30 min for a large CT volume of approximately 2000×2000×1000 voxels.

IRAS 00500+6713 is a hypothesized remnant of a Type Iax supernova SN 1181. Multiwavelength observations have revealed its complicated morphology; a dusty infrared ring is sandwiched by the inner and outer X-ray nebulae. We analyze the archival X-ray data taken by XMM-Newton and Chandra X-ray Observatory to constrain the angular radius, mass, and metal abundance of the X-ray nebulae, and construct a theoretical model describing the dynamical evolution of IRAS 00500+6713, including the effects of the interaction between the SN ejecta and the intense wind enriched with carbon-burning ashes from the central white dwarf (WD) J005311. We show that the inner X-ray nebula corresponds to the wind termination shock while the outer X-ray nebula to the shocked interface between the SN ejecta and the interstellar matter. The observed X-ray properties can be explained by our model with an ejecta kinetic energy of E _ej = (0.77–1.1) × 10 ^48 erg, an ejecta mass of M _ej = 0.18–0.53 M _⊙ , if the currently observed wind from WD J005311 started to blow t _w ≳ 810 yr after the explosion, i.e., approximately after 1990 CE. The inferred SN properties are compatible with those of Type Iax SNe and the timing of the wind launch may correspond to the Kelvin–Helmholtz contraction of the oxygen–neon core of WD J005311 that triggered a surface carbon burning. Our analysis supports that IRAS 00500+6713 is the remnant of SN Iax 1181 produced by a double degenerate merger of oxygen–neon and carbon–oxygen WDs, and WD J005311 is the surviving merger product.

Abstract Phlegmonous duodenitis is an extremely rare condition, and only a few cases have been previously reported. Here, we report a case of phlegmonous duodenitis caused by Streptococcus parasanguinis and Escherichia coli in a 78‐year‐old immunocompromised patient with diabetes mellitus and immunosuppressive drugs. Abdominal computed tomography showed diffuse thickening of the duodenum and gastric antrum, and esophagogastroduodenoscopy revealed some erosions with purulent discharge and reddish and edematous mucosa in the duodenal bulb. A bacteriological culture test detected the two abovementioned bacteria and established the diagnosis of phlegmonous duodenitis. Following the initiation of antibiotic treatment, his condition rapidly improved. Endoscopists should be aware of this rare entity and pay attention to the endoscopic duodenal findings similar to those of phlegmonous gastritis, particularly in immunocompromised patients who develop abdominal symptoms with severe inflammation.

Using a 3D scanner to inspect a 3D print is becoming more significant as the spectrum of applications for fused filament fabrication expands. We use the tool path, which describes the 3D printing process, as the nominal data to evaluate the manufacturing errors. However, since the 3D print’s coordinate system in the scan data is unknown, the 3D print must be aligned with the tool path before the nominal-actual comparison. Therefore, we present a novel alignment based on the 3D print’s microstructure. The proposed method first estimates the build direction and then aligns the 3D print with the tool path along the build direction. Finally, each layer of the 3D print is aligned with its corresponding layer of the tool path in the horizontal direction. The alignment result can be confirmed through the slice view. In addition, the performance, extension, and applications of the proposed method are discussed.

The kinematics of shocks, ejecta knots, and the compact remnant of a supernova remnant give insights into the nature of the progenitor and the surrounding environment. We report on a measurement of the proper motion of X-ray knots and rims of the magnetar-hosting supernova remnant RCW 103. Chandra data obtained in three epochs, 1999, 2010, and 2016, are used. We find a global deceleration of 12 knots and rims in both northern and southern regions within the last ∼24 yr, even though the age of the remnant is thought to be greater than 2 kyr. Some of them even changed their directions of motion from outward (∼1000 km s ^−1 ) to inward (∼−2000 km s ^−1 ). Our findings can be explained by a collision with a high-density medium at both the northern and southern edges of the remnant, although the remnant may still be expanding in the windblown cavity. The proper motion of the associated magnetar 1E 161348−5055 is possibly detected with a velocity of ≈500 km s ^−1 .

We present a time-resolved analysis using 39 ks NuSTAR observation data of the X-ray pulsar Centaurus X-3, covering an orbital-phase interval of Φ = 0.199–0.414. The orbital- and spin-phase variabilities are investigated through time-resolved spectra, light curves, and pulse profiles. The orbital-phase variability was due to the mixture of two comparable effects: intrinsic flux variability of ∼10% and obscuration by the clumpy stellar wind. The typical size and number density of the clumps are ∼9 × 10 ^10 cm and ∼3 × 10 ^12 cm ^−3 , respectively. In the spin-phase-resolved analysis, we detected variations in the spectral features of the continuum, the Fe line, and the cyclotron resonance scattering feature (CRSF). The photon index ranged from 0.72 to 1.06, corresponding to the difference in the Comptonization optical depth by a factor of ∼1.6. The equivalent width and intensity of the Fe line had negative correlations with the continuum flux. The central energy and the strength of the CRSF increased at the pulse maximum. The former ranged from 26.0 to 28.7 keV, while the latter varied by a factor of ∼1.9. The pulse profile was double-peaked in the low-energy band, and it gradually shifted to being single-peaked with energy, indicating the existence of two distinct emission patterns, corresponding to the pencil and fan beams. Finally, we found that the pulse profiles were highly stable along the orbital phase, within a variation degree of ∼20%, which provides evidence of the highly stable accretion stream of the binary system.

This study focuses on the formation process of plate shock in an underexpanded jet impinging on a flat plate. The jet discharged from a convergent nozzle is underexpanded when the pressure ratio across the nozzle exceeds the critical value. When the jet impinges on a flat plate perpendicularly, a shock wave called ‘plate shock’ is formed in the jet. In such flow filed the impinging jet violently oscillates, which leads to a complicated flow field with a noise of high sound pressure level. In application of the jet to industrial use, careful attention should be paid to the behavior of jet with noise emission, in particular, the behavior of the plate shock. In this study, the nozzle-plate distance was changed, and the flow field was experimentally observed with attention to the formation of plate shock. Shadowgraph method was used to visualize the flow field and a structure of the jet was examined. As a result two weak shocks were observed upstream of the flat plate and these were found to play an important role in formation and disappearance on the plate shock.

An underexpanded radial jet is generated downstream of intake and exhaust valves of an internal combustion engine, a pressure control valve and so on. In addition, when a supersonic jet issuing from a circular nozzle impinges on a flat plate, the wall jet on the plate often becomes underexpanded and spreads out radially. The underexpanded jet has typical shock-cell structure and strongly oscillates and its behavior is known to cause many industrial problems. In this study, a jet structure and an emitted noise from an underexpanded jet radially discharged from a circular slit nozzle, which consists of two circular tubes, are examined experimentally for different nozzle pressure ratios and different diameters of tube, and the experimental results are compared with those of a two dimensional jet issuing from a rectangular nozzle. As a result, multiple ring-shaped shocks are visualized in the radial underexpanded jet, and the sound source of noise measured is found to be in the vicinity of the end of the second cell. Furthermore, collapse of the cellular structure of radial jet occurs upstream in comparison with the case of rectangular jet and the length of second cell is shown to be one of the most important parameter of a frequency of the emitted screech tone.

The authors present a method for extracting polygon data of endocranial surfaces from CT images of human crania. Based on the fact that the endocast is the largest empty space in the crania, we automate a procedure for endocast extraction by integrating several image processing techniques. Given CT images of human crania, the proposed method extracts endocranial surfaces by the following three steps. The first step is binarization in order to fill void structures, such as diploic space and cracks in the skull. We use a void detection method based on mathematical morphology. The second step is watershed-based segmentation of the endocranial part from the binary image of the CT image. Here, we introduce an automatic initial seed assignment method for the endocranial region using the distance field of the binary image. The final step is partial polygonization of the CT images using the segmentation results as mask images. The resulting polygons represent only the endocranial part, and the closed manifold surfaces are computed even though the endocast is not isolated in the cranium. Since only the isovalue threshold and the size of void structures are required, the procedure is not dependent on the experience of the user. The present paper also demonstrates that the proposed method can extract polygon data of endocasts from CT images of various crania.

This paper focuses on the behavior of shock waves formed in an underexpanded impinging jet. The jet becomes underexpanded when the pressure ratio exceeds the critical value across the convergent nozzle discharging it. When a flat plate is placed perpendicularly to the jet, the strong shock wave called ‘plate shock' appears in the flow field near the plate. The underexpanded jet discharged from a nozzle into the atmosphere is often used for industrial applications, e.g., an assist gas of laser cutting and a cooling jet in glass tempering process. The jet impinges on the work piece and spreads out on its surface. So this study concentrates on the relation between the jet oscillation and the location of the work piece and especially discusses behavior of shock formed in jet. The impinging jet was formed under conditions of different nozzle pressure ratios and nozzle-plate spacings and was visualized using the shadowgraph and schlieren methods. The instantaneous shape of jet was measured through analyzing the pictures taken at random under each condition and the oscillation pattern was examined. In addition, under the same conditions, a numerical study was carried out using TVD scheme. As a result, it was found that the oscillation pattern of plate shock depends on its location and the nozzle pressure ratio.

The authors propose a CT image segmentation method using structural analysis that is useful for objects with structural dynamic characteristics. Motivation of our research is from the area of genetic activity. In order to reveal the roles of genes, it is necessary to create mutant mice and measure differences among them by scanning their skeletons with an X-ray CT scanner. The CT image needs to be manually segmented into pieces of the bones. It is a very time consuming to manually segment many mutant mouse models in order to reveal the roles of genes. It is desirable to make this segmentation procedure automatic. Although numerous papers in the past have proposed segmentation techniques, no general segmentation method for skeletons of living creatures has been established. Against this background, the authors propose a segmentation method based on the concept of destruction analogy. To realize this concept, structural analysis is performed using the finite element method (FEM), as structurally weak areas can be expected to break under conditions of stress. The contribution of the method is its novelty, as no studies have so far used structural analysis for image segmentation. The method's implementation involves three steps. First, finite elements are created directly from the pixels of a CT image, and then candidates are also selected in areas where segmentation is thought to be appropriate. The second step involves destruction analogy to find a single candidate with high strain chosen as the segmentation target. The boundary conditions for FEM are also set automatically. Then, destruction analogy is implemented by replacing pixels with high strain as background ones, and this process is iterated until object is decomposed into two parts. Here, CT image segmentation is demonstrated using various types of CT imagery.