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Objectives The aim of this AFIRE (Atrial Fibrillation and Ischemic Events With Rivaroxaban in Patients With Stable Coronary Artery Disease) trial subgroup analysis was to examine rivaroxaban monotherapy benefits and their relation to the time between stenting and enrollment among patients after coronary stenting. Background Of 2,215 patients with atrial fibrillation and stable coronary artery disease in the AFIRE trial, rivaroxaban monotherapy was noninferior to rivaroxaban plus antiplatelet therapy (combination therapy) in terms of efficacy and superior for safety endpoints. However, thrombotic risk after antiplatelet therapy cessation remained a concern among 1,444 patients who had undergone coronary stenting >1 year before enrollment. Methods The benefits of rivaroxaban monotherapy in coronary stenting subgroups were assessed for efficacy (a composite of stroke, systemic embolism, myocardial infarction, unstable angina requiring revascularization, or death of any cause), safety (major bleeding defined according to International Society on Thrombosis and Haemostasis criteria), ischemic endpoints, net adverse clinical event, and time between stenting and enrollment. Results Efficacy and safety endpoints for monotherapy were superior to combination therapy, with HRs of 0.70 for efficacy (95% CI: 0.50-0.98; P = 0.036) and 0.55 for safety (95% CI: 0.33-0.92; P = 0.019). For ischemic endpoints, the HR was 0.82 (95% CI: 0.58-1.15; P = 0.240). The HR became smaller with longer time between stenting and enrollment (efficacy, P for interaction = 0.158; safety, P = 0.097). Conclusions In patients with atrial fibrillation after coronary stenting, the benefits of rivaroxaban monotherapy for efficacy and safety endpoints were consistent with those in the whole AFIRE trial population. The benefits became apparent with longer time between stenting and enrollment. (Atrial Fibrillation and Ischemic Events With Rivaroxaban in Patients With Stable Coronary Artery Disease Study [AFIRE]; UMIN000016612 , NCT02642419 )

The dynamics of globule motion are studied in situ during the deformation of globular semi-solid steel (Fe–2C–0.9Mn–0.5Si in mass%). Samples with globular morphology and 55–65% effective solid fraction were deformed in direct shear at a shear rate of ∼10 −3 s −1 during time-resolved synchrotron X-ray imaging. Globule rearrangement involving dilation was the main deformation mechanism. Agglomeration is shown to significantly influence rearrangement by increasing the effective size of structural units.

Since the liquid / liquid separation occurs in hypermonotectic alloys and the liquid / liquid interface agitates mass transfer around solidifying front, it is rather difficult to achieve the aligned-rod structure. The high magnetic filed such as 10T achieved the aligned-rod structure in the Al-10at%In alloys. The in-situ observations of the monotectic solidification in the Al-10at%In alloys were performed using synchrotron radiation X-ray. Coarse and fine In rods coexisted during the unidirectional solidification without magnetic field. The local melt flow induced by the In-rich liquid / Al-rich liquid interface enhanced the mass transfer and consequently the coarse rods could continuously grow. The suppression of the local melt flow of which scale was several 10 m by the high static magnetic field resulted in the aligned-rod structure.

Few techniques are available to assess air inclusions in opaque plastic materials. This study showed a remarkable contrast gain for small air voids by synchrotron radiation imaging with refraction mode: comparing an absorption image, a 60-fold gain in contrast was observed for a 66 µm void. Minimally, a 24 µm inclusion was visualised using a detector with 6 µm × 6 µm resolution. The mechanism of contrast gain for small inclusions on refraction images cannot be explained by X-ray absorption, and X-ray refraction was proposed as its cause. In order to analyse the object-size dependency of contrast, the signal intensity profile due to refracted X-rays at the boundary was fitted by an analytical serpentine curve, which is one of the cubic curves. Calculation showed that signal intensity at the centre of an object increased with the decrease of an object size by the overlapping of X-rays refracted to the inside, and that the increase was steep for objects of 100 µm and smaller. As a conclusion, X-ray refraction produced an extremely high contrast gain for small air voids in synchrotron radiation imaging with refraction mode, and consequently, this imaging will be a sensitive technique for non-destructive detection and mapping of minute air inclusions.

A novel technique for designing a radiator suitable for personal neutron dosemeter based on plastic track detector was discussed. A multi-layer structure has been proposed in the previous report, where the thicknesses of plural polyethylene (PE) layers and insensitive ones were determined by iterative calculations of double integral. In order to arrange this procedure and make it more systematic, unfolding calculation has been employed to estimate an ideal radiator containing an arbitrary hydrogen concentration. In the second step, realistic materials replaced it with consideration of minimisation of the layer number and commercial availability. A radiator consisting of three layers of PE, Upilex and Kapton sheets was finally designed, for which a deviation in the energy dependence between 0.1 and 20 MeV could be controlled within 18 %. An applicability of fluorescent nuclear track detector element has also been discussed.

This paper reports, the application of synchrotron radiation to basic medicine at SPring-8 involving instrumentation and medical application of imaging and scattering. Emphasis should be laid on X-ray dark-field imaging (DFI) whose goal is clinical diagnosis of organs that have been invisible by ordinary techniques. Development of this technique is under way both at SPring-8 and KEK. The X-ray optics of DFI comprises a Bragg asymmetric monochro-collimator and a Laue case analyzer with a diffraction index of 4 4 0 using the X-ray energy of 35 keV ( λ = 0.0354 nm ) in a parallel position. This analyzer that can provide with 80 mm×80 mm view size has 2.15 mm thickness. At present the spatial resolution is around 5–10 μm. Visibility of some organs such as soft bone tissue at excised human femoral head and breast cancer tissue is under test. This preliminary test shows that the DFI seems feasible in clinical diagnosis. Furthermore, a perspective view of application of synchrotron radiation to clinical medicine in Japan will be given.

Time-resolved X-ray imaging with monochromatic synchrotron radiation enabled in situ observation of dendritic growth and detachment of the fragmented dendrite arms during unidirectional solidification of Sn–21 mass% Bi alloys. A mold with a re-entrant channel was used for the unidirectional solidification. At the beginning of the solidification in the re-entrant channel, detachment of the fragments was observed after the interface broke down and formed the dendrites. In addition, the detachment was observed after the dendrites passing the re-entrant corner laterally grew at rather high growth rate. In both occasions, the detachments followed deceleration of the growth rate and some of them resulted in the stray crystals. The observation showed that the detachment of the fragmented arms could be a source of the stray crystals in the metallic alloys.

The 215-m-long beamline has been constructed as the first medium-length beamline of SPring-8 for the purpose of R&D of imaging techniques, development of X-ray optics, computed tomography for mineral science, medical imaging, and X-ray topography. By using the long beamline, large field and spatially coherent beam can be obtained. Advantage of long beamline is successfully demonstrated by the preliminary experiment such as one-shot topograph of 300-mm-diameter silicon crystal.

To evaluate the usefulness of a radiographic system with monochromatic synchrotron radiation to depict small vessels and peripheral secretory ducts.Radiography of various organs was tested in 14 anesthetized dogs and pancreatography was performed in an excised human pancreas by using the following system: monochromatic synchrotron radiation with an energy level just above the k absorption edge of iodine as an x-ray source and a high-definition TV system with a high-light-sensitivity image pick-up tube camera coupled with a fluorescent screen as a detector.This system allowed depiction of small vessels (diameter50-100 microns) of the heart (penetrating transmural artery), brain (perforating arteries that arise directly in the circle of Willis), and intestinal organs (vasa recta and their submucosal communications) and of small branches (down to the fifth order) of the pancreatic duct.The synchrotron radiation system may be useful for evaluating microcirculatory disorders and early-stage malignant tumors in various human organs.

In this study, the composite magnetic nanoparticles of coated SiO nano film with about 8 nm size and high saturation magnetization value, were synthesized by liquid phase precipitation method. The magnetic nanoparticles can be dispersed in various liquid media, widely known as magnetic fluids or ferrofluids with both magnetic and liquid properties. The materials been collected great interests and more and more attentions to focus into Drug Delivery System (DDS) as a new technology in this paper. We use the composite nanoparticles to disperse H2O and inject the solutions into rat's in-vivo organs. And, in the experiments by using a strong photon beam of SPring-8 Synchrotron Radiation facility, the distribution stat and the effects of magnetic field as well as drug delivery behaviour of nanoparticles in the rat' kidney are verified by the in-vivo observations.

In this paper, we propose a on‐line monitoring technique using electromagnetic acoustic transducer (EMAT). In the series of laboratory experiments, carbon steel pipes were used and each sample was fabricated to simulate FAC. Electromagnetic acoustic resonance method (EMAR) is successfully tested for pipe wall thickness measurements. The validity and the feasibility of our method are also demonstrated through the laboratory experiments.

New finding in this study is a contrast enhancement of microcalcifications in a synchrotron radiation image with refraction mode. The contrast enhancement has obviously a greater contribution than edge enhancement to high sensitivity in detecting microcalcifications in synchrotron radiation image with refraction mode

The antiarrhythmic effect of magnesium sulfate (Mg) as well as the hemodynamics were studied using the coronary ligation and reperfusion models in rats. In the study on coronary ligation arrhythmia, i.v. administration of Mg (0.6, 2, 6, 20 and 60 micromol) was conducted at 5 min after coronary ligation. Mg had an action to decrease the total number of premature ventricular contraction (PVC), the duration of ventricular tachycardia (VT), the frequency of VT and ventricular fibrillation (Vf) and the mortality ratio for 30 min after coronary ligation. In the 6-60 micromol groups, significant antiarrhythmic action (p0.01 vs. control) was attained. In the study on reperfusion arrhythmia, i.v. administration of Mg (20, 60 and 200 micromol) was conducted at 4 min after coronary ligation, and at 1 min after ligation, the coronary artery was reperfused. Mg had an action to decrease the frequency of Vf, the mortality ratio and the duration of VT and Vf and to extend the interval between the initiation of reperfusion and the occurrence of VT and Vf for 10 min after reperfusion. In the 200 micromol group, significant antiarrhythmic action (p0.05 vs. control) was attained. Administration of Mg decreased the heart rate and blood pressure. We concluded that Mg can control myocardial ischemia-induced and reperfusion-induced arrhythmia and that sudden cardiac death which occurs as a result of arrhythmia can be prevented.

Time-resolved in situ observations using synchrotron radiation X-rays showed that γ nucleation difficulties resulted in a massive transformation from the δ phase to the γ phase. The massive transformation occurred even in high-carbon steel (0.45 mass% C) at a cooling rate of 0.33 K/s or more. A crystallographic relationship in which the close-packed (111) plane of the γ phase tended to coincide with the close-packed (110) plane of the δ phase suggested that the γ phase nucleated in a favorable plane in the δ phase. Observations of the sequence in the initial stage of solidification showed that the induced strain and strain rate in the massive transformation were larger than those expected in peritectic solidification. These observations will help us to understand deformation of solidifying shells and to build a physical model.

Time-resolved absorption imaging using synchrotron radiation X-rays allows us to observe solidification of metallic alloys of interest. This paper presents peritectic solidification in Sn-Cd alloy and Fe-C alloys. In unidirectional solidification of Sn-Cd alloy, the formation of a banded structure, in which two phases were alternatively piled up in the growth direction, was clearly observed. Sequence of nucleation or fluctuation of triple junction (primary phase / secondary phase / liquid) resulted in the banded structure. Ease of nucleation for both phases contributed to the banded structure formation. In carbon steel (Fe-0.45mass%C), the transformation from δ phase to γ phase was observed. At lower cooling rates, γ phase was produced in semisolid state of δ phase and liquid, indicating the peritectic reaction occurred during solidification. In contrast, δ phase transformed into γ phase when solidification nearly completed at temperatures 100K below the liquidus temperature. Namely, the transformation seemed to be massive. The observation showed that two different transformation modes operated in Fe-C alloy.

Iodine K-edge subtraction techniques using monochromatized X-ray have been investigated at several synchrotron radiation facilities for transvenous coronary angiography. We developed an iodine-filter imaging system for real-time imaging. A combination of the iodine filter and a single energy monochromatized X-ray produces two-energy images for the iodine K-edge subtraction technique. An X-ray exposure system consists of the iodine filter and a monochromator. X-ray energies are switched by the filter chopping of the X-ray beam. A detector consists of an X-ray image intensifier and a video camera. An oscillating mirror is installed between the collimating lens and camera lens in an image distributor. Each image that corresponds to the iodine- and aluminum- (non-iodine-) filtered images is focused side by side on the photoconductive layer of the camera tube by the oscillating mirror.

Retinotopy and binocular responsiveness were studied extracellularly in a total of 278, 61, 110 and 275 cells sampled in areas 17, 18, 19 and Clare-Bishop (CB) of Siamese cats. The misalignment of the visual axes of the two eyes was determined by the pupil reflex method in the behaving animal. The recording sessions were conducted under N2O anesthesia, supplemented with continuous infusion of short-lasting anesthetics (Saffan, Glaxo) and muscle relaxants (Gallamine triethiodide) using two types of visual stimulators presenting two-dimensional (2D) motion stimuli and the visual cues for three-dimensional (3D) motion. All of the nine Siamese cats demonstrated Boston type retinotopic abnormalities in all of cortical areas 17-19 and CB. Very few binocular cells were present in areas 17-19 and the posterior (A1-P2) CB but they were numerous in most of CB (A9-4). A significant fraction (36/78) of binocular cells in the major CB of the Siamese cats demonstrated similar response selectivity to that reported in normal CB cortex for stimulation with the 3D motion cues under both null disparity and strabismic conditions (binocular receptive fields for two eyes were optically superposed or separated by the strabismic angles estimated in the individual animals). These findings indicate that the binocular signals converging to the CB cells through different pathways (signals coming from the contralateral eye via the ipsilateral hemisphere including the interlaminar nucleus and areas 17-19, and commissural signals from the ipsilateral eye via the contralateral areas 17-19 and CB) were integrated to yield useful information for the recognition of 3D motion, and that the major CB is an actual site of binocular integration at least in Siamese cats, rather than being merely a reflection of the information processing before the CB cortex.

A total of 783 cells were studied extracellularly in anterior (A10-13), posterior (A4-8), and intermediate regions (A8.1-9.9) of Clare-Bishop (CB) cortex of the cat, which were defined according to the anteroposterior coordinate of the stereotaxic axis and probably corresponded to the antero- (AMLS), postero-medial lateral suprasylvian cortex (PMLS), and the border region between the two subareas, respectively. The study was conducted under N2O anesthesia supplemented with continuous infusion of short-lasting anesthetics (Saffan, Glaxo or Etomidate, Janssen), using three types of visual stimulators presenting two- (2D) and three-dimensional (3D) motion stimuli, and visual cues contained in the 3D motion. Neuronal responsiveness was essentially similar between the anterior and posterior CB subdivisions. Both areas contained 1) AP, 2) RC and 3) FP cells, selectively responsive to approaching, recessive and fronto-parallel motion, and 4) NS and 5) U cells, nonselectively responsive and unresponsive to any of these motions. However, a quantitative difference was found: 1) In the posterior CB the FP cell population was the largest, and the frequency reduced in the order of AP, NS, RC and U cells, while the largest population in the anterior CB consisted of the AP and U cells, and the frequency reduced in the order of FP, RC and NS cells. 2) 3D (AP and RC) cells in the posterior CB responded preferentially to approaching motion at a distal range, while those in the anterior CB preferred motion at a proximal range. 3) The 3D cells in the posterior CB were more sensitive to the motion cue and demonstrated lower thresholds for the size cue than the anterior CB cells. 4) The anterior CB cells generally demonstrated high-pass velocity tuning (cut-off around 10 degrees/s) for monoclonal 2D stimulation, while the posterior CB cells demonstrated a broad band-pass tuning (4-120 degrees/s). These findings suggest functional differentiation in neuronal representation of 3D motion signals between the two subdivisions of CB cortex.

Four kinds of Si(Li) and a high‐purity Ge x‐ray detectors have been tested to measure the thicknesses of gold contact layers by comparing the response of the primary Rb‐Kα x‐rays with that of the induced Au‐Lα x rays. Observed thicknesses ranged from 140 to 260 A. Near the x‐ray energies of Au‐M subshell absorption edges, the contribution of x‐ray transmission through the observed gold layers to the detection efficiency is greater than or equivalent to that of the inherently attached 7.6‐μm beryllium window. Hence, one must be careful in the determination of the detection efficiency in x‐ray semiconductor detector when low‐energy x rays of less than about 4 keV are measured.

Thin self-supporting Cu targets in 11–250 μg/cm2 thickness were bombarded with 50–165 MeV Cuqi+ ions (7 ⩽qi⩽ 24) to investigate the target thickness dependence of inner shell vacancy production processes in the symmetric collision of Cu + Cu. Doppler-shifted projectile K X-rays were discriminated from the target K X-rays, and the projectile and target K X-ray yields were separately measured as a function of target thickness. The K X-ray yields emitted from the projectile and the target Cu atoms are strongly dependent on the projectile initial charge state and target thickness for all the investigated collision systems of Cuqi+ + Cu. From the observed K X-ray yields, K-shell vacancy production cross sections averaged over the target thickness t of projectile σ KV and target σ ∗ KV were separately derived taking into account the fluorescence yield that can be estimated from the Kα X-ray energy shift. When the values of σ KV and σ ∗ KV are extrapolated to zero foil thickness, the K shell vacancy formed in the collision has been found to be equally shared between projectile and target in a single collision. With the increase of penetration depth, however, the values of σ ∗ KV are greater than those of σ KV presumably due to electron transfer of a target K electron to the projectile K vacancy. the evolution process of projectile excited states as a function of target thickness and the resulting variation of projectile and target K X-ray emissions are discussed.

Heavy projectile K X-ray emission yields have been measured as a function of carbon target thickness for incident ions of 40 MeV Cl 13+ , 95 MeV Cl 8+, 12+, 15+, 16+, 17+ , 115 MeV Fe 10+ , 120 MeV Cu 11+ , 150 MeV Cu 13+ and 140 MeV Br 12+ . In the thin target foil region where the loss and capture process of projectile L shell electrons is not equilibrated, projectile K X-ray emission cross sections have been found to be significantly influenced by the variation of the number of projectile L shell electrons.

The K alpha / K beta ratio of Mn KX-rays scattered by metallic samples changed remarkably with the geometry between the sample and the (55)Fe source-Si(Li) detector system. On the contrary, this intensity ratio changed little in the cases of non-metallic scatterer samples such as lucite or mylar. This difference is interpreted as due to the occurrence of strong or weak interference in the coherent scattering photons.

Equilibrium charge state distributions have been measured for 30–110 MeV Si ions in carbon and gold foils and 25–142 MeV Cl ions in carbon foils. Obtained values of mean charge states have been well reproduced by the empirical formula by Shima et al. in both ion energy dependence and foil Z 2 dependence. Asymmetric charge state distributions are in fairly good agreement with the prediction of the chi-squared model by Baudinet-Robinet.

Energy shifts of target Kα x-rays in 80 and 120 MeV Cu + Cu collisions have been observed to vary 90–108 and 100–137 eV, respectively, in target thicknesses of 1–20 μg/cm2 range where the projectile charge states change from nonequilibrium to equilibrium.

Since the discovery of projectile x-ray production nonlinearity as function of solid target thickness by Betz et al.1, many authors have applied the rate equation of projectile inner shell vacancy to the investigation of dynamic processes of heavy ion-atom collisions. In contrast to the existing reports of nonlinearity of target x-ray production cross sections, the experiments to observe the projectile x-rays have been limited.

Observation of gamma-ray background has been done by using a Ge(Li) semiconductor detector when it was placed inside the lead shielding material. With the aid of a very simple model calculation, the concentration of 210Pb radioisotope embedded in the lead material has been estimated to be 0.1-0.4 (Bq/Pb-g) (3-12 (pCi/Pb-g). The origin of Pb-KX-ray emission, the highest peak in the background spectrum, has been investigated by comparing the 210Pb-47 keV gamma-ray and Pb-KX-ray peak counts. As the results, about 50 +/- 30% of Pb-KX-ray production is estimated to be due to the Pb-K shell photoionization which is induced by the bremsstrahlung of 210Bi beta-ray.

To date, most of the experiments to obtain the characteristic x-ray energy shifts resulting from the multiple ionization in heavy ion-atom collisions have been done by using a foil or a dense gas target, under the condition that the target is thick enough for the projectile charge to reach the equilibrium state. In this work is reported (1) the variation of projectile or target K x-ray energy shift in the nonequilibrium target thickness region and (2) the correspondence of K x-ray energy shift to the target material dependence of heavy ion equilibrium charge state.

A 73-year-old woman without liver cirrhosis developed choreoathetoid movements of the limbs due to portal-systemic encephalopathy. A prominent spleno-renal shunt was demonstrated by non-invasive methods (abdominal computed tomography and sonography) as well as arterial portography. The choreoathetoid movements were improved by a protein-restricted diet and administration of lactulose. A portal systemic shunt should be considered when investigating choreoathetosis, even in patients without liver cirrhosis.