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We studied the strain introduced in a Si(111) substrate due to MeV ion implantation using extremely asymmetric x-ray diffraction and measured the rocking curves of asymmetrical 113 diffraction for the Si substrates implanted with a 1.5 MeV Au2+ ion at fluence values of 1×1013, 5×1013, and 1×1014/cm2. The measured curves consisted of a bulk peak and accompanying subpeak with an interference fringe. The positional relationship of the bulk peak to the subpeak and the intensity variation of those peaks with respect to the wavelengths of the x rays indicated that crystal lattices near the surface were strained; the lattice spacing of surface normal (111) planes near the surface was larger than that of the bulk. Detailed strain profiles along the depth direction were successfully estimated using a curve-fitting method based on Darwin’s dynamical diffraction theory. Comparing the shapes of resultant strain profiles, we found that a strain evolution rapidly occurred within a depth of ∼300 nm at fluence values between 1×1013 and 5×1013/cm2. This indicates that formation of the complex defects progressed near the surface when the fluence value went beyond a critical value between 1×1013 and 5×1013/cm2 and the defects brought a large strain to the substrate. [ABSTRACT FROM AUTHOR]

Snoring is the most common symptom of obstructive sleep apnoea (OSA). Several researchers have reported differences between the power spectra of non-OSA and OSA snorers. The traditional approach over the years has been to record snore sounds at a bandwidth of < 5 kHz. Narrowing of the upper airways during OSA events and the resulting upward shift of snore frequencies also lend support to the idea of examining snore sounds beyond 5 kHz. In this paper, we compute the power spectra of snores in three different bands defined as: low-frequency band (LFB: < 5 kHz); middle-frequency band (MFB: 5-10 kHz) and high-frequency band (HFB: 10-20 kHz). We illustrate that there is a significant difference between non-OSA snorers (Apnoea Hypopnoea Index (AHI) < 10) and OSA snorers (AHI > 10) in the region > 5 kHz. We then develop a feature to diagnose OSA based on the spectral differences in the high frequency region and evaluate its performance on a database of 20 subjects. Our results strongly suggest that the high-frequency region of the snore sounds carry information, hitherto disregarded, on the disease of sleep apnoea. [ABSTRACT FROM AUTHOR]

We have established a novel method which make electron scattering off short-lived radioactive nuclei come into being. This novel method was named SCRIT (Self-Confining RI ion Target). It was based on the well known "ion trapping" phenomenon in electron storage rings. Stable nucleus, 133Cs, was used as target nucleus in the R&D experiment. The luminosity of interaction between stored electrons and Cs ions was about 1.02(0.06) × 1026cm-2s-1 at beam current around 80 mA. The angular distribution of elastically scattered electrons from trapped Cs ions was measured. And an online luminosity monitor was used to monitor the change of luminosity during the experiment. [ABSTRACT FROM AUTHOR]

We studied the effect of annealing in a hydrogen gas on the crystal structure of strontium bismuth tantalate (SBT) by means of X-ray diffraction measurements. The hydrogen reduction happens mainly in bismuth oxide layers followed by the decomposition of pseudo-perovskite layers. With increasing the annealing time and/or temperature, new crystalline products such as bismuth, strontium tantalate, and bismuth oxide, and an unidentified crystal are observed along with non-crystalline materials. Decomposition of SBT and recrystallization of the decomposed materials occur even from the initial stage of the hydrogen reduction process. [ABSTRACT FROM AUTHOR]

A polycapillary X-ray lens is an effective optics to obtain a μm-size X-ray beam for micro-X-ray fluorescence spectrometry (μ-XRF). We developed a μ-XRF instrument using a polycapillary X-ray lens, which also enabled us to perform Grazing Exit μ-XRF (GE-μ-XRF). The evaluated diameter of the primary X-ray beam was 48 μm at the focal distance of the X-ray lens. Use of this instrument enabled two-dimensional mapping of the elemental distributions during growth of the plant “Quinoa”. The results of the mapping revealed elemental transition during growth. In addition, a small region of thin film was analyzed by GE-μ-XRF. We expect that GE-μ-XRF will become an effective method of estimating the film thickness of a small region. [Copyright &y& Elsevier]

We have studied the crystal orientation of Ag thin films on a [formula] surface using grazing incidence X-ray diffraction with synchrotron radiation. After preparation of a [formula] surface, 50 ML Ag was deposited on the [formula] at the substrate temperature of 50–300 K. We found the [formula] structure at the interface. As for the Ag film, the Ag}111{ plane was mainly grown on the surface. The domain size of the Ag films strongly depends on the substrate temperature of the deposition. The domain size is found to be regulated by an original domain size of the [formula] surface before Ag deposition, which relates to the surface-structural phase transition. By scattering intensity measurements in the reciprocal lattice space, we found streaky scattering along the [formula] direction parallel to the surface. This scattering is thought to originate from the CTR (crystal truncation rod) scattering from a sidewall plane of the Ag {111} nanometer-scale crystals. [formula available in full text]. [ABSTRACT FROM AUTHOR]

197Au Mössbauer spectra from Au/TM (TM = Fe, Co, Ni) multilayers consist mainly of two components. One component shows a large hyperfine magnetic field due to the hybridization at the interface between Au and ferromagnetic layers. The other component is nonmagnetic arising from the middle part of the Au layers. From the fractional area of the magnetic components in each spectrum, the Au atoms in 0.4 nm Au layers are perturbed by the Fe and Ni layers, and Co layers perturb 0.3 nm Au layers at the interface. [ABSTRACT FROM AUTHOR]

Objectives: Desmopressin is widely used for nocturia in patients with nocturnal polyuria. We investigated the continuation rate and adherence for desmopressin in patients with overactive bladder and nocturia using a claims database and evaluated factors that improved adherence., Methods: Patients with nocturia in a Japanese claims database who started desmopressin between September 2019 and July 2021 were evaluated. Drug persistence was assessed using the Kaplan-Meier method for initial prescription of desmopressin. The proportion of days covered (PDC) was also evaluated among patients with prescription persistence. Multivariate analysis was performed using logistic regression analysis to identify factors predicting adherence to desmopressin., Results: The study included 72,888 patients entered into Japan Medical Data Center (JMDC) database between September 2019 and July 2021. For the 236 patients prescribed desmopressin formulations, mean prescription duration was 114 days. Among the total cases, 90 (38.1%) cases were prescribed only once, mean PDC was 0.60, and the number of high-adherence patients (PDC ≥ 0.80) was 108 (45.8%). Desmopressin prescription doses were fixed in 216 patients and adjusted in 20 patients. Multivariate analysis identified prescription dose adjustment for desmopressin as significantly associated with high PDC., Conclusion: Desmopressin showed a 38% dropout rate after the first dose. However, high medication continuation and high medication adherence rates (PDC) could be maintained with prescription adjustments. Careful patient monitoring and appropriate adjustment of the desmopressin dosage appear to be important factors in improving nocturia., (© 2024 Wiley Periodicals LLC.)

Background: Body mass index (BMI) of patients with ischemic stroke (IS) has been associated with prognosis and disability in studies in the United States. Although the Asian population is leaner, the optimal BMI for stroke-related disability remains unknown., Objectives: To clarify the association between BMI and disability in patients with IS from a national database in Japan., Methods: The present study included 522,421 patients with IS identified in the JROAD-DPC database from April 2016 to March 2020. We used the WHO classification of BMI, which divides Asia-Pacific patients into five groups, to categorize BMI and the modified Rankin Scale (mRS) to assess stroke-related disability at admission and discharge. After multiple imputation for missing values, we conducted a multiple mixed-effect logistic regression analysis for poor mRS score (>2) in September 2023. In addition, we created a restricted cubic spline model between the odds ratio (OR) for poor mRS and BMI., Results: The mRS score worsened during hospitalization in 60.1% of the patients with IS, and 45.7% had a poor mRS score at discharge. Overweight patients had the lowest OR of having a poor mRS score (OR: 0.898, 95% confidence interval: 0.895-0.902). The spline curve for the OR for poor mRS score was U-shaped with a BMI of 24.7 kg/m 2 as the apex value., Conclusion: The present study revealed a U-shaped relationship between BMI and stroke-related disability, with overweight patients having the lowest OR for disability at discharge.

This study aimed to evaluate the impact of radiation dose and focal spot size on the image quality of super-resolution deep-learning reconstruction (SR-DLR) in comparison with iterative reconstruction (IR) and normal-resolution DLR (NR-DLR) algorithms for cardiac CT. Catphan-700 phantom was scanned on a 320-row scanner at six radiation doses (small and large focal spots at 1.4-4.3 and 5.8-8.8 mGy, respectively). Images were reconstructed using hybrid-IR, model-based-IR, NR-DLR, and SR-DLR algorithms. Noise properties were evaluated through plotting noise power spectrum (NPS). Spatial resolution was quantified with task-based transfer function (TTF); Polystyrene, Delrin, and Bone-50% inserts were used for low-, intermediate, and high-contrast spatial resolution. The detectability index (d') was calculated. Image noise, noise texture, edge sharpness of low- and intermediate-contrast objects, delineation of fine high-contrast objects, and overall quality of four reconstructions were visually ranked. Results indicated that among four reconstructions, SR-DLR yielded the lowest noise magnitude and NPS peak, as well as the highest average NPS frequency, TTF 50% , d' values, and visual rank at each radiation dose. For all reconstructions, the intermediate- to high-contrast spatial resolution was maximized at 4.3 mGy, while the lowest noise magnitude and highest d' were attained at 8.8 mGy. SR-DLR at 4.3 mGy exhibited superior noise performance, intermediate- to high-contrast spatial resolution, d' values, and visual rank compared to the other reconstructions at 8.8 mGy. Therefore, SR-DLR may yield superior diagnostic image quality and facilitate radiation dose reduction compared to the other reconstructions, particularly when combined with small focal spot scanning., (© 2024. Australasian College of Physical Scientists and Engineers in Medicine.)

The 88 th Annual Scientific Meeting of the Japanese Circulation Society (JCS2024) was held from Friday, March 8 th to Sunday, March 10 th in Kobe, Japan. The main theme of this 3-day meeting was "The Future of Cardiology: Challenges in Overcoming Cardiovascular Disease". As COVID-19 has been finally conquered, with revision of its categorization under the Infectious Disease Control Law and relaxation of infection prevention measures, it was once again possible to have face-to-face presentations and lively discussion. JCS2024 was a major success, with 19,209 participants and attendees, thanks to the greatly appreciated cooperation and support from all affiliates.

There is no treatment for acute aortic dissection (AAD) targeting inflammatory cells. We aimed to identify the new therapeutic targets associated with inflammatory cells. We characterized the specific distribution of myeloid cells of both human type A AAD samples and a murine AAD model generated using angiotensin II (ANGII) and β-aminopropionitrile (BAPN) by single-cell RNA sequencing (scRNA-seq). We also examined the effect of an anti-interleukin-1β (IL-1β) antibody in the murine AAD model. IL1B + inflammatory macrophages and classical monocytes were increased in human AAD samples. Trajectory analysis demonstrated that IL1B + inflammatory macrophages differentiated from S100A8/9/12 + classical monocytes uniquely observed in the aorta of AAD. We found increased infiltration of neutrophils and monocytes with the expression of inflammatory cytokines in the aorta and accumulation of inflammatory macrophages before the onset of macroscopic AAD in the murine AAD model. In blocking experiments using an anti-IL-1β antibody, it improved survival of murine AAD model by preventing elastin degradation. We observed the accumulation of inflammatory macrophages expressing IL-1β in both human AAD samples and in a murine AAD model. Anti-IL-1β antibody could improve the mortality rate in mice, suggesting that it may be a treatment option for AAD., (© 2024. The Author(s).)

To assess the diagnostic performance of unenhanced electrocardiogram (ECG)-gated cardiac computed tomography (CT) for detecting myocardial edema, using MRI T2 mapping as the reference standard. This retrospective study protocol was approved by our institutional review board, which waived the requirement for written informed consent. Between December 2017 to February 2019, consecutive patients who had undergone T2 mapping for myocardial tissue characterization were identified. We excluded patients who did not undergo unenhanced ECG-gated cardiac CT within 3 months from MRI T2 mapping or who had poor CT image quality. All patients underwent unenhanced ECG-gated cardiac CT with an axial scan using a third-generation, 320 × 0.5 mm detector-row CT unit. Two radiologists together drew regions of interest (ROIs) in the interventricular septum on the unenhanced ECG-gated cardiac CT images. Using T2 mapping as the reference standard, the diagnostic performance of unenhanced cardiac CT for detecting myocardial edema was evaluated by using the area under the receiver operating characteristic curve with sensitivity and specificity. Youden index was used to find an optimal sensitivity-specificity cutoff point. A cardiovascular radiologist independently performed the measurements, and interobserver reliability was assessed using intraclass correlation coefficients for CT value measurements. A P value of <.05 was considered statistically significant. We included 257 patients who had undergone MRI T2 mapping. Of the 257 patients, 35 patients underwent unenhanced ECG-gated cardiac CT. One patient was excluded from the study because of poor CT image quality. Finally, 34 patients (23 men; age 64.7 ± 14.6 years) comprised our study group. Using T2 mapping, we identified myocardial edema in 19 patients. Mean CT and T2 values for 34 patients were 46.3 ± 2.7 Hounsfield unit and 49.0 ± 4.9 ms, respectively. Mean CT values moderately correlated with mean T2 values (Rho = -0.41; P < .05). Mean CT values provided a sensitivity of 63.2% and a specificity of 93.3% for detecting myocardial edema, with a cutoff value of ≤45.0 Hounsfield unit (area under the receiver operating characteristic curve = 0.77; P < .01). Inter-observer reproducibility in measuring mean CT values was excellent (intraclass correlation coefficient = 0.93; [95% confidence interval: 0.86, 0.96]). Myocardial edema could be detected by CT value of myocardium in unenhanced ECG-gated cardiac CT., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2024 the Author(s). Published by Wolters Kluwer Health, Inc.)