Search

Your search keyword '"Sugiura, Toshihiko"' showing total 664 results
Start Over Author "Sugiura, Toshihiko"
664 results on '"Sugiura, Toshihiko"'

1. Is Ethereum Proof of Stake Sustainable? $-$ Considering from the Perspective of Competition Among Smart Contract Platforms $-$

Author

Saito, Kenji, Soejima, Yutaka, Sugiura, Toshihiko, Kitamura, Yukinobu, and Iwamura, Mitsuru

Subjects
Computer Science - Computers and Society, Economics - General Economics
Abstract

Since the Merge update upon which Ethereum transitioned to Proof of Stake, it has been touted that it resulted in lower power consumption and increased security. However, even if that is the case, can this state be sustained? In this paper, we focus on the potential impact of competition with other smart contract platforms on the price of Ethereum's native currency, Ether (ETH), thereby raising questions about the safety and sustainability purportedly brought about by the design of Proof of Stake., Comment: 30 pages, 1 figure

Published
2023

8. Altered gut microbiota and its association with inflammation in patients with chronic thromboembolic pulmonary hypertension: a single-center observational study in Japan

Author

Ikubo, Yumiko, Sanada, Takayuki Jujo, Hosomi, Koji, Park, Jonguk, Naito, Akira, Shoji, Hiroki, Misawa, Tomoko, Suda, Rika, Sekine, Ayumi, Sugiura, Toshihiko, Shigeta, Ayako, Nanri, Hinako, Sakao, Seiichiro, Tanabe, Nobuhiro, Mizuguchi, Kenji, Kunisawa, Jun, Suzuki, Takuji, and Tatsumi, Koichiro

Published
2022
Full Text
View/download PDF

25. Aorta and main pulmonary artery segmentation using stacked U‐Net and localization on non‐contrast‐enhanced computed tomography images.

Author

Suzuki, Hidenobu, Kawata, Yoshiki, Aokage, Keiju, Matsumoto, Yuji, Sugiura, Toshihiko, Tanabe, Nobuhiro, Nakano, Yasutaka, Tsuchida, Takaaki, Kusumoto, Masahiko, Marumo, Kazuyoshi, Kaneko, Masahiro, and Niki, Noboru

Subjects
PULMONARY artery, COMPUTED tomography, THORACIC aorta, AORTA, TRACHEA, RECEIVER operating characteristic curves, VENAE cavae
Abstract

Background: The contact between the aorta, main pulmonary artery (MPA), main pulmonary vein, vena cava (VC), and esophagus affects segmentation of the aorta and MPA in non‐contrast‐enhanced computed tomography (NCE‐CT) images. Purpose: A two‐stage stacked U‐Net and localization of the aorta and MPA were developed for the segmentation of the aorta and MPA in NCE‐CT images. Methods: Normal‐dose NCE‐CT images of 24 subjects with chronic thromboembolic pulmonary hypertension (CTEPH) and low‐dose NCE‐CT images of 100 subjects without CTEPH were used in this study. The aorta is in contact with the ascending aorta (AA) and MPA, the AA with the VC, the aortic arch (AR) with the VC and esophagus, and the descending aorta (DA) with the esophagus. These contact surfaces were manually annotated. The contact surfaces were quantified using the contact surface ratio (CSR). Segmentation of the aorta and MPA in NCE‐CT images was performed by localization of the aorta and MPA and a two‐stage stacked U‐Net. Localization was performed by extracting and processing the trachea and main bronchus. The first stage of the stacked U‐Net consisted of a 2D U‐Net, 2D U‐Net with a pre‐trained VGG‐16 encoder, and 2D attention U‐Net. The second stage consisted of a 3D U‐Net with four input channels: the CT volume and three segmentation results of the first stage. The model was trained and tested using 10‐fold cross‐validation. Segmentation of the entire volume was evaluated using the Dice similarity coefficient (DSC). Segmentation of the contact area was also assessed using the mean surface distance (MSD). The statistical analysis of the evaluation underwent a multi‐comparison correction. CTEPH and non‐CTEPH cases were classified based on the vessel diameters measured from the segmented MPA. Results: For the noncontact surfaces of AA, the MSD of stacked U‐Net was 0.31 ± 0.10 mm (p < 0.05) and 0.32 ± 0.13 mm (p < 0.05) for non‐CTEPH and CTEPH cases, respectively. For contact surfaces with a CSR of 0.4 or greater in AA, the MSD was 0.52 ± 0.23 mm (p < 0.05), and 0.68 ± 0.29 mm (p > 0.05) for non‐CTEPH and CTEPH cases, respectively. MSDs were lower than those of 2D and 3D U‐Nets for contact and noncontact surfaces; moreover, MSDs increased slightly with larger CSRs. However, the stacked U‐Net achieved MSDs of approximately 1 pixel for a wide contact surface. The area under the receiver operating characteristic curve for CTEPH and non‐CTEPH classification using the right main pulmonary artery (RMPA) diameter was 0.97 (95% confidence interval [CI]: 0.94–1.00). Conclusions: Segmentation of the aorta and MPA on NCE‐CT images were affected by vascular and esophageal contact. The application of stacked U‐Net and localization techniques for non‐CTEPH and CTEPH cases mitigated the impact of contact, suggesting its potential for diagnosing CTEPH. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

29. Clinical significance of lung cross‐sectional area measured by computed tomography in chronic thromboembolic pulmonary hypertension: The correlation with pulmonary hemodynamics and the limitations

Author

Kuriyama, Ayaka, primary, Kasai, Hajime, additional, Sugiura, Toshihiko, additional, Nagata, Jun, additional, Naito, Akira, additional, Sekine, Ayumi, additional, Shigeta, Ayako, additional, Sakao, Seiichiro, additional, Ishida, Keiichi, additional, Matsumiya, Goro, additional, Tanabe, Nobuhiro, additional, and Suzuki, Takuji, additional

Published
2023
Full Text
View/download PDF

36. Impact of residual pulmonary hypertension on long‐term outcomes after pulmonary endarterectomy in the modern era

Author

Ishida, Keiichi, primary, Kohno, Hiroki, additional, Matsuura, Kaoru, additional, Sugiura, Toshihiko, additional, Sanada, Takayuki J., additional, Naito, Akira, additional, Shigeta, Ayako, additional, Suda, Rika, additional, Sekine, Ayumi, additional, Masuda, Masahisa, additional, Sakao, Seiichiro, additional, Tanabe, Nobuhiro, additional, Tatsumi, Koichiro, additional, and Matsumiya, Goro, additional

Published
2023
Full Text
View/download PDF

37. Automated detection method of thoracic aorta calcification from non-contrast CT images using mediastinal anatomical label map

Author

Suzuki, Hidenobu, Kawata, Yoshiki, Sugiura, Toshihiko, Tanabe, Nobuhiro, Matsumoto, Yuji, Tsuchida, Takaaki, Kusumoto, Masahiko, Marumo, Kazuyoshi, Kaneko, Masahiro, Niki, Noboru, Suzuki, Hidenobu, Kawata, Yoshiki, Sugiura, Toshihiko, Tanabe, Nobuhiro, Matsumoto, Yuji, Tsuchida, Takaaki, Kusumoto, Masahiko, Marumo, Kazuyoshi, Kaneko, Masahiro, and Niki, Noboru

Abstract

Progression of thoracic aortic calcification (TAC) has been shown to be associated with hard cardiovascular events including stroke and all-cause mortality as well as coronary events. In this study, we propose an automated detection method of TACs of non-contrast CT images using mediastinal anatomical label map. This method consists of two steps: (1) the construction of a mediastinal anatomical label map, and (2) the detection of TACs using the intensity and the mediastinal anatomical label map. The proposed method was applied to two non-contrast CT image datasets: 24 cases of chronic thromboembolic pulmonary hypertension (CTEPH) and 100 non-CTEPH cases of low-dose CT screening. The method was compared with two-dimensional U-Nets and the Swin UNETR. The results showed that the method achieved significantly higher F1 score of 0.937 than other methods for the non-CTEPH case dataset (p-value < 0.05, pairwise Wilcoxon signed rank test with Bonferroni correction).

Published
2023

40. Pulmonary Veno-occlusive Disease that Developed Following Hematopoietic Stem Cell Transplantation for Acute Myeloid Leukemia

Author

Takeda, Kenichiro, primary, Naito, Akira, additional, Sugiura, Toshihiko, additional, Ishige, Masaki, additional, Shikano, Kohei, additional, Abe, Mitsuhiro, additional, Kasai, Hajime, additional, Miyakuni, Shota, additional, Yamashita, Shu, additional, Shigeta, Ayako, additional, Sakao, Seiichiro, additional, and Suzuki, Takuji, additional

Published
2023
Full Text
View/download PDF

43. Two cases of pulmonary arterial hypertension with specific vascular Мalformations and unique eosinophilic inflammation in carriers of the RNF213 p. Arg4810Lys variant: Case series

Author

Takeda, Kenichiro, primary, Sekine, Ayumi, additional, Tanabe, Nobuhiro, additional, Sugiura, Toshihiko, additional, Shigeta, Ayako, additional, Kitahara, Shinsuke, additional, Imai, Shun, additional, Okaya, Tadasu, additional, Nagata, Jun, additional, Naito, Akira, additional, Sakao, Seiichiro, additional, Tatsumi, Koichiro, additional, and Suzuki, Takuji, additional

Published
2023
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results