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High-precision segmentation and quantification of tunnel lining crack using an improved DeepLabV3+
Get PDFCurrent semantic segmentation models have limitations in addressing tunnel lining crack, such as high complexity, misidentification, or inability to detect tiny cracks in specific practical scenarios, which is crucial for precise assessment of tunnel lining health. We developed a novel approach called EDeepLab, aiming to achieve a higher precision detection and segmentation of lining surface crack. EDeepLab improves upon the original DeepLabV3+ framework by replacing its backbone network with an optimized lightweight EfficientNetV2. The amount of EfficientNetV2 block computation is reduced and a self-designed shallow feature fusion module is used to merge the layers to enhance parameter utilization efficiency. Furthermore, the normalization-based attention module and convolutional block attention module attention mechanisms are integrated to classify and process both high and low dimensional information features. This allows for comprehensive utilization of global semantic information and channel information, thereby enhancing the model’s feature extraction capability. Results in constructed metro-tunnel crack dataset demonstrate that the number of parameters is reduced from 144.45 M in the DeepLabV3+ to 99.80 M in the EDeepLab. EDeepLab achieves a mean intersection over union of 84.77%, mean pixel accuracy of 94.96%, and frames per second of 18.52 f/s. The proposed EDeepLab outperforms other models including U-Net, ResNet and fully convolutional networks in the quantitative analysis of tiny cracks and noise interference.Underground Space, 22, pp.96-109; 2025journal articl
Toward the development of learning methods with distributed processing using securely divided data
Get PDFTo pave the way to a super-smart society, artificial intelligence (AI) methods are being developed to discover and analyze necessary information instantly from cyberspace and utilize it in physical space. However, privacy protection is necessary for AI to process big data in cyberspace. From the viewpoint of developing safe and secure machine learning methods, research on (1) homomorphic cryptography, (2) differential privacy, (3) secure multiparty computation, and (4) federated learning is underway. The goal of these studies is to develop useful learning methods while maintaining data privacy. We propose a method to address the trade-off between security and usability in machine learning. This method balances usability and data confidentiality by using decomposed data to achieve secure distributed processing. However, such methods using distributed processing increase computational and communication overhead as the number of servers increases. To address this problem, we propose a method to control the computational complexity as the number of servers increases. On the basis of these studies, this study first systematically addresses the construction of secure distributed processing methods with decomposed data. A comprehensive approach is essential to advance the field and allow these methods to be effectively applied to different domains. On the basis of these methods, we propose back-propagation and neural gas learning methods with reduced computational and communication requirements. We then apply the proposed methods to numerical simulations of class classification and clustering problems and show that accuracy comparable to that of conventional models can be achieved with 1∕ computational and communication complexity for distributed models with servers.Computers and Electrical Engineering, 123, art. no. 110160; 2025journal articl
Amyloid Deposition Mainly Localized in the Basal Area of the Left Ventricle in a Patient with Amyloid Transthyretin Cardiac Amyloidosis
Get PDFA 74-year-old Japanese man was admitted to our hospital for catheter ablation of paroxysmal atrial fibrillation. Transthoracic echocardiography revealed basal interventricular septal hypertrophy without apical sparing. Cardiac magnetic resonance imaging revealed late gadolinium enhancement in the hypertrophic lesions. The Kumamoto criteria was one point, and the patient had no carpal tunnel syndrome. However, technetium-99m pyrophosphate scintigraphy revealed an accumulation in the basal region of the left ventricle. A skin biopsy revealed transthyretin (TTR) amyloid deposition. A TTR gene examination revealed no variants. This case suggests that amyloid deposition in TTR may occur in the basal area of the interventricular septum.Internal Medicine, 64(4), pp.569-573; 2025journal articl
Customs Clearance Efficiency and Its Impact on National Income: Strategies for Integrated International Trade Supply Chain Management
Get PDFThis paper suggests that raising the efficiency of customs clearance procedures to the world’s top level could increase Japan’s GNI per capita by about 20％, which will be expected to yield significant growth results, and confirms that it is consistent with the Melitz model. As a practical measure necessary to improve the efficiency of customs clearance procedures, it is important to promote the use of a trade data exchange platform using blockchain, which can realize a system that effectively improves the efficiency of customs clearance procedures in a short period of time. The realization of integrated international trade supply chain management across different countries, which will lead to a dramatic reduction in trade costs, is approaching as a global movement, although there are challenges.経営と経済, 104(3-4), pp.1-51; 2025departmental bulletin pape
2024年度五島焼八本木窯跡発掘調査概要報告
Get PDFIn the late Edo period, porcelain production began in the Goto Islands in the west of Kyushu. ５ old kiln sites have been discovered on Fukue Island. The authors began an archaeological survey of these kiln sites in 2016. From 2018 to 2021, we had excavated at the Tanoe kiln site, and have excavated at the Happongi kiln since 2022. This paper is a report of the excavation survey of the Happongi kiln conducted in 2024.According to old records, Happongi kiln began producing porcelain in 1805 by inviting potters from Takahama in the Amakusa region. An old map shows us porcelain production space in those day. We could find some walls and floors of the firing chamber by this excavation. As a result we were able to estimate the length and size of the climbing kiln.多文化社会研究, 11, pp.353-370; 2025departmental bulletin pape
Clinical characteristics and prognosis of pulmonary aspergillosis complicating interstitial lung diseases
No full textBackground: Pulmonary aspergillosis can complicate interstitial lung diseases (ILDs) during immunosuppressive treatment. This study aimed to clarify the clinical characteristics and prognostic differences of pulmonary aspergillosis in patients with ILDs by disease subtypes. Methods: Patients diagnosed with both ILDs and pulmonary aspergillosis were retrospectively analyzed at Nagasaki University Hospital between October 1, 2008, and March 31, 2022. Pulmonary aspergillosis was categorized as invasive pulmonary aspergillosis (IPA) or chronic pulmonary aspergillosis (CPA). CPA was further subdivided into simple pulmonary aspergilloma (SPA), chronic cavitary pulmonary aspergillosis (CCPA), and subacute invasive aspergillosis (SAIA). Clinical characteristics and prognostic outcomes were compared among the subtypes. Results: Fifty patients with both diseases were analyzed: 38 had CPA and 12 had IPA. All patients with IPA had a history of corticosteroid use and a significantly higher prevalence of diabetes mellitus than those with CPA. In contrast, honeycombing changes on chest computed tomography (CT) were more frequently observed in patients with CPA than in those with IPA. Kaplan–Meier analysis showed that patients with IPA had significantly higher mortality rates than those with CPA, and that among CPA subtypes, patients with SAIA had significantly higher mortality rates than those with SPA or CCPA. Univariate analysis showed that the presence of SAIA or IPA was significantly associated with 1-year mortality compared to other subtypes. The type of underlying ILD did not affect the prognosis. Conclusions: Clinical characteristics and prognoses of pulmonary aspergillosis in patients with ILDs vary by subtype.Respiratory Investigation, 63(6), pp.1293-1299; 2025journal articl
Activation of the α7nAChR by GTS-21 mitigates septic tubular cell injury and modulates macrophage infiltration
No full textNagasaki University (長崎大学)博士(医学)The most common and serious complication among hospitalized and critically ill patients is sepsis-associated acute kidney damage (S-AKI), which raises the risk of comorbidities and is linked to a high mortality rate. Cholinergic anti-inflammatory pathway (CAP), an anti-inflammatory pathway mediated by the vagus nerve, acetylcholine, and α7 nicotinic acetylcholine receptors (α7nAChRs), offers new perspectives for the treatment of S-AKI. In this study, we investigated the role of CAP and α7nAChR in kidney injury by employing an LPS-induced septic kidney injury mouse model and GTS-21 intervention. C57BL/6 mice were injected with LPS, with or without GTS-21, in different subgroups. Kidney function was assessed by plasma creatinine, histology, and markers of kidney injury 24 h after intervention. The results demonstrated that GTS-21 could inhibit the systemic inflammatory response and directly protect the tubular cell injury from LPS. To explore the novel gene involved in this response, RNA sequencing of the renal proximal tubular epithelial cell (HK-2), pretreated with LPS and GTS-21, was conducted. The results indicate that GTS-21 administration reduces LPS-induced cytokines and chemokines secretion by HK-2, including CCL20, a potent chemokine attracting monocytes/macrophages. Furthermore, a macrophage transmigration assay revealed that GTS-21 inhibits macrophage transmigration by downregulating the expression of CCL20 in HK-2 cells. In conclusion, GTS-21, as an α7nAChR agonist, emerges as a noteworthy and versatile treatment for S-AKI. Its dual function of directly protecting renal tubular cells and regulating inflammatory responses represents a major advancement in the treatment of sepsis-induced AKI. This finding might pave the way for novel approaches to improving patient outcomes and reducing death rates in sepsis-related complications.長崎大学学位論文 学位記番号:博(医歯薬)甲第1723号 学位授与年月日:令和7年9月19日Author: Aobing Yang, Chia-Hsien Wu, Sayumi Matsuo, Ryusuke Umene, Yasuna Nakamura, Tsuyoshi InoueCitation: International Immunopharmacology, 138, art. no. 112555; 2024Nagasaki University (長崎大学), 博士(医学) (2025-09-19)doctoral thesi