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The generalization of deep neural network algorithms to a broader population is an important challenge in the medical field. We aimed to apply self-supervised learning using masked autoencoders (MAEs) to improve the performance of the 12-lead electrocardiography (ECG) analysis model using limited ECG data. We pretrained Vision Transformer (ViT) models by reconstructing the masked ECG data with MAE. We fine-tuned this MAE-based ECG pretrained model on ECG-echocardiography data from The University of Tokyo Hospital (UTokyo) for the detection of left ventricular systolic dysfunction (LVSD), and then evaluated it using multi-center external validation data from seven institutions, employing the area under the receiver operating characteristic curve (AUROC) for assessment. We included 38,245 ECG-echocardiography pairs from UTokyo and 229,439 pairs from all institutions. The performances of MAE-based ECG models pretrained using ECG data from UTokyo were significantly higher than that of other Deep Neural Network models across all external validation cohorts (AUROC, 0.913–0.962 for LVSD, p < 0.001). Moreover, we also found improvements for the MAE-based ECG analysis model depending on the model capacity and the amount of training data. Additionally, the MAE-based ECG analysis model maintained high performance even on the ECG benchmark dataset (PTB-XL). Our proposed method developed high performance MAE-based ECG analysis models using limited ECG data. [ABSTRACT FROM AUTHOR]

Introduction: Ischemic heart disease is a leading cause of death worldwide, and its importance is increasing with the aging population. The aim of this study was to evaluate the accuracy of SurvTrace, a survival analysis model using the Transformer—a state-of-the-art deep learning method—for predicting recurrent cardiovascular events and stratifying high-risk patients. The model's performance was compared to that of a conventional scoring system utilizing real-world data from cardiovascular patients. Methods: This study consecutively enrolled patients who underwent percutaneous coronary intervention (PCI) at the Department of Cardiovascular Medicine, University of Tokyo Hospital, between 2005 and 2019. Each patient's initial PCI at our hospital was designated as the index procedure, and a composite of major adverse cardiovascular events (MACE) was monitored for up to two years post-index event. Data regarding patient background, clinical presentation, medical history, medications, and perioperative complications were collected to predict MACE. The performance of two models—a conventional scoring system proposed by Wilson et al. and the Transformer-based model SurvTrace—was evaluated using Harrell's c-index, Kaplan–Meier curves, and log-rank tests. Results: A total of 3938 cases were included in the study, with 394 used as the test dataset and the remaining 3544 used for model training. SurvTrace exhibited a mean c-index of 0.72 (95% confidence intervals (CI): 0.69–0.76), which indicated higher prognostic accuracy compared with the conventional scoring system's 0.64 (95% CI: 0.64–0.64). Moreover, SurvTrace demonstrated superior risk stratification ability, effectively distinguishing between the high-risk group and other risk categories in terms of event occurrence. In contrast, the conventional system only showed a significant difference between the low-risk and high-risk groups. Conclusion: This study based on real-world cardiovascular patient data underscores the potential of the Transformer-based survival analysis model, SurvTrace, for predicting recurrent cardiovascular events and stratifying high-risk patients. [ABSTRACT FROM AUTHOR]

Microvascular thrombosis is a typical symptom of COVID‐19 and shows similarities to thrombosis. Using a microfluidic imaging flow cytometer, we measured the blood of 181 COVID‐19 samples and 101 non‐COVID‐19 thrombosis samples, resulting in a total of 6.3 million bright‐field images. We trained a convolutional neural network to distinguish single platelets, platelet aggregates, and white blood cells and performed classical image analysis for each subpopulation individually. Based on derived single‐cell features for each population, we trained machine learning models for classification between COVID‐19 and non‐COVID‐19 thrombosis, resulting in a patient testing accuracy of 75%. This result indicates that platelet formation differs between COVID‐19 and non‐COVID‐19 thrombosis. All analysis steps were optimized for efficiency and implemented in an easy‐to‐use plugin for the image viewer napari, allowing the entire analysis to be performed within seconds on mid‐range computers, which could be used for real‐time diagnosis. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the association of systemic oxidative stress markers and optic nerve head (ONH) blood flow in normal-tension glaucoma (NTG) patients, as well as sex differences in this association. Methods: This was a cross-sectional study of 235 eyes with NTG of 134 patients (56 male, 78 female; mean age, 60.9±14.1 years). Laser speckle flowgraphy (LSFG) was used to measure ONH blood flow (mean blur rate in the tissue area of the ONH; MBR-T) and LSFG pulse-waveform parameters, including flow acceleration index in the tissue area of the ONH (FAI-T). Oxidative stress markers, diacron-reactive oxygen metabolites (d-ROMs), and biological antioxidant potential (BAP) were measured with a free radical elective evaluator. Spearman's rank correlation test and a multivariate linear mixed-effect model were used to investigate factors associated with ONH blood flow. Results: MBR-T was significantly correlated with age (rs = -0.28, p < 0.001), mean arterial pressure (rs = -0.20, p = 0.002), intraocular pressure (rs = 0.24, p < 0.001), peripapillary retinal nerve fiber layer thickness (rs = 0.62, p < 0.001), and disc area (rs = -0.26, p < 0.001), but not with serum d-ROM level. Separate analyses of the subjects divided by sex showed that BAP was positively correlated to MBR-T (rs = 0.21, p = 0.036) and FAI-T (rs = 0.36, p < 0.001) only in male subjects. Similarly, BAP was significantly associated with MBR-T (β = 0.25, p = 0.026) and FAI-T (β = 0.37, p < 0.001) in male subjects in a multivariate linear mixed-effect model. Conclusion: A lower serum antioxidant level, as indicated by BAP, was associated with reduced ONH blood flow only in male NTG patients. Our findings suggest that there are sex differences in the involvement of oxidative stress in the pathogenesis of reduced ocular blood flow in NTG. [ABSTRACT FROM AUTHOR]

Coronary angiography (CAG) is still considered the reference standard for coronary artery assessment, especially in the treatment of acute coronary syndrome (ACS). Although aging causes changes in coronary arteries, the age-related imaging features on CAG and their prognostic relevance have not been fully characterized. We hypothesized that a deep neural network (DNN) model could be trained to estimate vascular age only using CAG and that this age prediction from CAG could show significant associations with clinical outcomes of ACS. A DNN was trained to estimate vascular age using ten separate frames from each of 5,923 CAG videos from 572 patients. It was then tested on 1,437 CAG videos from 144 patients. Subsequently, 298 ACS patients who underwent percutaneous coronary intervention (PCI) were analysed to assess whether predicted age by DNN was associated with clinical outcomes. Age predicted as a continuous variable showed mean absolute error of 4 years with R squared of 0.72 (r = 0.856). Among the ACS patients stratified by predicted age from CAG images before PCI, major adverse cardiovascular events (MACE) were more frequently observed in the older vascular age group than in the younger vascular age group (p = 0.017). Furthermore, after controlling for actual age, gender, peak creatine kinase, and history of heart failure, the older vascular age group independently suffered from more MACE (hazard ratio 2.14, 95% CI 1.07 to 4.29, p = 0.032). The vascular age estimated based on CAG imaging by DNN showed high predictive value. The age predicted from CAG images by DNN could have significant associations with clinical outcomes in patients with ACS. [ABSTRACT FROM AUTHOR]

The use of a buffer layer in a separation layer containing commercial polyimide or acrylic allows normal laser separation without using special laser irradiation, even if foreign particles (approximately 1 mmΦ) are attached to a glass substrate. A linear laser used for the crystallization of low-temperature polysilicon can be used. [ABSTRACT FROM AUTHOR]

A prototype compact 310-Gb/s (25.78-Gb/s $\times12$ -ch) parallel-optical-transceiver module for large-capacity and high-density optical interconnects was fabricated. The structure of the optical module provides efficient heat dissipation and high optical-coupling efficiency. The fabricated transceiver demonstrated 25.78-Gb/s error-free multimode transmission over 100 m. [ABSTRACT FROM PUBLISHER]

We previously reported a large, seamless, Kawara-type multidisplay formed by overlapping flexible organic lightemitting diode panels, each with two transparent edges. The multidisplay reported in this study creates a more seamless image because of the inclusion of a circular polarizer combined with a flexible panel using an optically isotropic film. [ABSTRACT FROM AUTHOR]

We established a fabrication process of flexible displays, adopting a transfer technology using an inorganic tungsten-separation-layer. Our separation process requires physical force and water. Tungsten oxide over tungsten in the separation layer plays a key role in separation: water injection into the tungsten oxide reduces the force necessary for separation. In this study, we describe the apparatus we built for the fabrication process of flexible displays. This apparatus fabricated an 8k (7680 × 4320 effective pixels) flexible organic light-emitting diode display. [ABSTRACT FROM AUTHOR]

We established a manufacturing process of flexible displays, adopting a transfer technology using tungsten separation layers. We performed separation with water. In this study, we describe the apparatus we built for the manufacturing process. This apparatus fabricated an 8k (7680 × 4320 effective pixels) flexible organic light-emitting diode display. [ABSTRACT FROM AUTHOR]

In this study, a 5.9-inch foldable active-matrix organic light emitting diode (AMOLED) display was developed. A folding test was performed repeatedly. The display survived the folding test (100,000 folds) with a curvature radius of 2 mm. To protect an organic light emitting diode (OLED) against moisture, inorganic passivation layers are provided on the upper and lower sides of the flexible display. Using our transfer technology, high density passivation layers can be obtained. The measured water vapor transmission rate of the layer is 7 × 10−6 g/m2⋅day or less, which improves OLED reliability. With these techniques, we have developed a book-type display, which is repeatedly foldable like a book, and a tri-fold display including a display area, which is foldable in three. [ABSTRACT FROM AUTHOR]

A folding screen type OLED display was developed (Fig. 1) to demonstrate the application of a flexible display. The display surface can be bent with a curvature radius of 4 mm To protect an OLED against moisture, inorganic passivation layers are provided on the upper and lower sides of the flexible display. Using our transfer technology, dense passivation layers can be obtained The measured water vapor transmission rate of the layer is 7 × 10−6 g/m2.day or less, which improves OLED reliability. [ABSTRACT FROM AUTHOR]

We study the site-bond percolation on a hierarchical scale-free network, namely, the decorated (2,2)-flower, by using the renormalization group technique. The phase diagram essentially depends on the fraction of occupied sites. Surprisingly, when each site is unoccupied even with a small probability, the system permits neither the percolating phase nor the nonpercolating phase, but rather only critical phases. Although the order parameter always remains zero, a transition still exists between the critical phases that is characterized by the value of the fractal exponent, which measures the degree of criticality; the system changes from one critical state to another with the jump of the fractal exponent at the transition point. The phase boundary depends on the fraction of occupied sites. When the fraction of unoccupied sites exceeds a certain value, the transition line between the critical phases disappears, and a unique critical phase remains [ABSTRACT FROM AUTHOR]

To assess the impact of genetic risk estimation for primary open-angle glaucoma (POAG) in Japanese individuals. Cross-sectional analysis. Genetic risk scores (GRSs) were constructed based on a genome-wide association study (GWAS) of POAG in Japanese people. A total of 3625 Japanese individuals, including 1191 patients and 2434 controls (Japanese Tohoku), were used for the model selection. We also evaluated the discriminative accuracy of constructed GRSs in a dataset comprising 1034 patients and 1147 controls (the Japan Glaucoma Society Omics Group [JGS-OG] and the Genomic Research Committee of the Japanese Ophthalmological Society [GRC-JOS]) and 1900 participants from a population-based study (Hisayama Study). We evaluated 2 types of GRSs: polygenic risk scores using the pruning and thresholding procedure and a GRS using variants associated with POAG in the GWAS of the International Glaucoma Genetics Consortium (IGGC). We selected the model with the highest areas under the receiver operating characteristic curve (AUC). In the population-based study, we evaluated the correlations between GRS and ocular measurements. Proportion of patients with POAG after stratification according to the GRS. We found that a GRS using 98 variants, which showed genome-wide significance in the IGGC, showed the best discriminative accuracy (AUC, 0.65). In the Japanese Tohoku, the proportion of patients with POAG in the top 10% individuals was significantly higher than that in the lowest 10% (odds ratio [OR], 6.15; 95% confidence interval [CI], 4.35–8.71). In the JGS-OG and GRC-JOS, we confirmed similar impact of POAG GRS (AUC, 0.64; OR [top vs. bottom decile], 5.81; 95% CI, 3.79–9.01). In the population-based study, POAG prevalence was significantly higher in the top 20% individuals of the GRS compared with the bottom 20% (9.2% vs. 5.0%). However, the discriminative accuracy was low (AUC, 0.56). The POAG GRS was correlated positively with intraocular pressure (r = 0.08: P = 4.0 × 10–4) and vertical cup-to-disc ratio (r = 0.11; P = 4.0 × 10–6). The GRS showed moderate discriminative accuracy for POAG in the Japanese population. However, risk stratification in the general population showed relatively weak discriminative performance. Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article. [ABSTRACT FROM AUTHOR]

In this paper, we report a 3.4-inch flexible top-emitting AMOLED display with remarkably high resolution using oxide TFTs. Our transfer technology has an advantage of fabricating high-performance TFTs and a high-resolution AMOLED Display on a flexible substrate. [ABSTRACT FROM AUTHOR]

A 76-year-old man who had undergone tricuspid annuloplasty 13 years earlier was admitted to our hospital because of a high fever. Although he was treated with antibiotics for pneumonia, a mild fever persisted. Computed tomography and gallium scintigraphy revealed a mediastinal abscess with an expanded polytetrafluoroethylene (ePTFE) membrane. There were no positive cultures or sternal changes indicating poststernotomy mediastinitis. The membrane was removed by a left parasternal approach without resternotomy, and its total removal was essential for the patient's recovery. This is the first reported case of sterile mediastinal abscess caused by an ePTFE membrane after a cardiac operation. [ABSTRACT FROM AUTHOR]

A planar light-emitting device was developed using a nanocrystalline porous Si layer as an energetic hot electron generator and a ZnS:Mn film as a luminescent film. Uniform orange light emission was observed at relatively low bias voltages. Furthermore, a cavity built using two Ag mirrors on both sides of the ZnS:Mn film operated well and effectively narrowed both the photoluminescence and electroluminescence (EL) spectra. The emission characteristics under the device operation in a three-electrode configuration clarified the EL mechanism based on the ballistic electron generation in the nanocrystalline Si layer followed by the direct excitation of the fluorescent film. The device, which provides a ballistic lighting concept for inorganic EL with a low driving voltage, is a very attractive all-thin-film surface-emitting light source for various applications. [ABSTRACT FROM AUTHOR]

Although thoracic endovascular repair (TEVAR)-specific complications often develop, stent-graft collapse is a rare, but fatal complication that requires attention. A 62-year-old male underwent TEVAR for a saccular distal arch aortic aneurysm. After the placement of the Gore TAG (W. L. Gore & Associates, Inc., Newark, DE, USA) from zones 2 to 4, a Najuta endograft (Kawasumi Laboratories, Inc., Tokyo, Japan) was deployed from zone 0. Neither intraoperative angiography nor postoperative contrast-enhanced computed tomography (CT) showed endoleaks or migration. On day 12 after surgery, the patient suddenly lost consciousness during rehabilitation, and CT revealed the collapse of the Najuta endograft. In emergency surgery, the Najuta endograft was removed and the TAG was sutured to the aorta. Although the patient survived, he developed irreversible higher brain dysfunction. The cause of the collapse was examined by the manufacturer and only a slight bird-beak configuration was noted. There were no other findings to indicate the cause of the collapse. The Najuta endograft is a semi-customized system that is created according to the three-dimensional morphology of each individual aortic arch and, thus, is expected to follow the flexion of this vessel. Nevertheless, the risk of collapse needs to be considered.

Comprehensive management approaches for patients with ischemic heart disease (IHD) are important aids for prognostication and treatment planning. While single-modality deep neural networks (DNNs) have shown promising performance for detecting cardiac abnormalities, the potential benefits of using DNNs for multimodality risk assessment in patients with IHD have not been reported. The purpose of this study was to investigate the effectiveness of multimodality risk assessment in patients with IHD using a DNN that utilizes 12-lead electrocardiograms (ECGs) and chest X-rays (CXRs), with the prediction of major adverse cardiovascular events (MACEs) being of particular concern.DNN models were applied to detection of left ventricular systolic dysfunction (LVSD) on ECGs and identification of cardiomegaly findings on CXRs. A total of 2107 patients who underwent elective percutaneous coronary intervention were categorized into 4 groups according to the models' outputs: Dual-modality high-risk (n = 105), ECG high-risk (n = 181), CXR high-risk (n = 392), and No-risk (n = 1,429).A total of 342 MACEs were observed. The incidence of a MACE was the highest in the Dual-modality high-risk group (P < 0.001). Multivariate Cox hazards analysis for predicting MACE revealed that the Dual-modality high-risk group had a significantly higher risk of MACE than the No-risk group (hazard ratio (HR): 2.370, P < 0.001), the ECG high-risk group (HR: 1.906, P = 0.010), and the CXR high-risk group (HR: 1.624, P = 0.018), after controlling for confounding factors.The results suggest the usefulness of multimodality risk assessment using DNN models applied to 12-lead ECG and CXR data from patients with IHD.