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Left ventricular dilatation (LVD) and left ventricular hypertrophy (LVH) are risk factors for heart failure, and their detection improves heart failure screening. This study aimed to investigate the ability of deep learning to detect LVD and LVH from a 12-lead electrocardiogram (ECG). Using ECG and echocardiographic data, we developed deep learning and machine learning models to detect LVD and LVH. We also examined conventional ECG criteria for the diagnosis of LVH. We calculated the area under the receiver operating characteristic (AUROC) curve, sensitivity, specificity, and accuracy of each model and compared the performance of the models. We analyzed data for 18,954 patients (mean age (standard deviation): 64.2 (16.5) years, men: 56.7%). For the detection of LVD, the value (95% confidence interval) of the AUROC was 0.810 (0.801-0.819) for the deep learning model, and this was significantly higher than that of the logistic regression and random forest methods (P0.001). The AUROCs for the logistic regression and random forest methods (machine learning models) were 0.770 (0.761-0.779) and 0.757 (0.747-0.767), respectively. For the detection of LVH, the AUROC was 0.784 (0.777-0.791) for the deep learning model, and this was significantly higher than that of the logistic regression and random forest methods and conventional ECG criteria (P0.001). The AUROCs for the logistic regression and random forest methods were 0.758 (0.751-0.765) and 0.716 (0.708-0.724), respectively. This study suggests that deep learning is a useful method to detect LVD and LVH from 12-lead ECGs.

To capture an all-in-focus and 3D depth image, shape from focus method is widely used. The phase accuracy of the image candidates should be processed and adjusted beforehand. Phase only correction method was employed in this work and to accelerate the processing speed, the image processing by Fast Fourier Transform (FFT) was optimized. Meanwhile, the processing task was assigned in several parallel threads so that the performance would be improved. The method was used on a variable focus imaging system, and, as a result, the processing speed was improved to around 2.5-fps.

Background: Cardiac 13 N-ammonia ( 13 N-NH3) positron emission tomography (PET) is approved by Japanese Ministry of Health, Labour and Welfare for diagnosis of ischemic heart disease. New PET camera recently has three-dimensionalmode acquisition and ordered subset expectation maximization (OSEM) reconstruction with time-of-flight (TOF) and point spread function (PSF) correction technology. The aim of the phantom study was to evaluate the usefulness of this novel technology using 13 N-NH3 and 18 F-fluorodeoxyglucose ( 18 F-FDG). Method: PET imaging was performed using a lung-heart torso phantom with myocardial perfusion defects. The indices of defect contrast, the coefficient of variation (CV) and the index of homogeneity were analyzed by using four reconstruction schemes, including OSEM, OSEM+TOF, OSEM+PSF, and TOF+PSF correction methods. Results: The phantom study showed that TOF resulted in improvements of defect lesion detectability with low statisticalnoise. The defect contrast index of TOF +PSF was significantly larger than that of OSEM only (p= 0.048). The cardiac percent root mean square uncertainty (RMSU) with PSF was 25.9 %i n OSEM+PSF and 20.9 %i n TOF+PSF. In contrast cardiac % RMSU without PSF correction was 14.8% in OSEM and 15.3 %i n TOF, which was lower than that with PSF correction. The average wall counts were homogeneous in four reconstruction methods in 13 N-NH3. The value of % CV on the profile curve of 13 N-NH3 images was confirmed to be smaller than 5% in all reconstruction methods. Conclusions: The new PET technology with TOF and PSF correction may extend the possibility of precise analysis of abnormal perfusion defects, and clinical applications are expected.

The purpose of study is to make the meaning of Scale in Architecture clear by doing an analysis of various literatures which explain the terms of scale. The results of this analysis, the scale of architecture is not only the system of size in various levels (physical, visual, technological, economical, etc.) , but also the allometrical relations between the proportions which exist in similar forms of different size each other.

For the purpose of investigating the correlation between host gas adsorption ability and structural flexibility, the combination of metal benzoate complexes [M(II)(2)(bza)(4)] (M(II) = Rh (a), Cu (b); bza = benzoate) and pyrazine derivatives (pyz = pyrazine (1), 2-mpyz = 2-methylpyrazine (2), 2,3-dmpyz = 2,3-dimethylpyrazine (3)) yields a series of one-dimensionally assembled complexes. The study of the adsorption properties of this series was examined for CO(2), H(2), N(2), O(2), and Ar gases at 195 K (CO(2)) or at 77 K (all others). The adsorption manners of these complexes are similar for each gas, while the pressure at which adsorption started or rapidly grew increased with a rise in the number of methyl groups in the case of adsorbable gases. The maximum amount of adsorption was a positive integer, e.g., 3 molecules per M(2) unit for 1 and 2 and 2 molecules per M(2) unit for 3 in the case of CO(2) adsorption for all complexes at 0.1 MPa of adsorbable gases. Structural transformation was observed accompanying gas adsorption. This transformation was observed when the adsorption amount reached 1 molecule per M(2) unit, suggesting a correlation of the adsorption amount and dynamic adsorption behavior. Single-crystal X-ray analyses of nonincluded crystals and CO(2) inclusions for all hosts (1-3) revealed that large structural changes occurred through CO(2) adsorption to increase the inner space for adsorption gases, depending on the substituents on the pyrazine ring. These facts were confirmed as a transition by DSC measurements using a mixed CO(2)/N(2) gas atmosphere. Solid-state (1)H and (2)H NMR studies of the crystalline sample of 1a and its partially deuterated samples of 1a' (deuterated phenyl group) and 1a'' (deuterated pyrazine) revealed rapid 180 degree-flip motions of the aromatic rings of the host skeletons, which form the walls of the channels. These "rotating" motions would help the diffusion of CO(2) molecules through a narrow channel at relatively low pressure. Indeed, the motions of phenyl groups and methyl-substituted pyrazine moieties of phenyl deuterated 3a were confirmed to be very slow by solid-state (1)H and (2)H NMR spectra, where the amount of adsorbed gas molecules was small for 3a at 0.1 MPa of CO(2).