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Background: This study aimed to develop an automated segmentation system for biliary structures using a deep learning model, based on data from magnetic resonance cholangiopancreatography (MRCP). Materials and methods: Living liver donors who underwent MRCP using the gradient and spin echo technique followed by threedimensional modeling were eligible for this study. A three-dimensional residual U-Net model was implemented for the deep learning process. Data were divided into training and test sets at a 9:1 ratio. Performance was assessed using the dice similarity coefficient to compare the model's segmentation with the manually labeled ground truth. Results: The study incorporated 250 cases. There was no difference in the baseline characteristics between the train set (n =225) and test set (n=25). The overall mean Dice Similarity Coefficient was 0.80 ± 0.20 between the ground truth and inference result. The qualitative assessment of the model showed relatively high accuracy especially for the common bile duct (88%), common hepatic duct (92%), hilum (96%), right hepatic duct (100%), and left hepatic duct (96%), while the third-order branch of the right hepatic duct (18.2%) showed low accuracy. Conclusion: The developed automated segmentation model for biliary structures, utilizing MRCP data and deep learning techniques, demonstrated robust performance and holds potential for further advancements in automation. [ABSTRACT FROM AUTHOR]

Purpose We aimed to assess the clinical efficacy of transcatheter arterial embolization (TAE) for treating hemothorax caused by chest trauma. Materials and Methods Between 2015 and 2019, 68 patients (56 male; mean age, 58.2 years) were transferred to our interventional unit for selective TAE to treat thoracic bleeding. We retrospectively investigated their demographics, angiographic findings, embolization techniques, technical and clinical success rates, and complications. Results Bleeding occurred mostly from the intercostal arteries (50%) and the internal mammary arteries (29.5%). Except one patient, TAE achieved technical success, defined as the immediate cessation of bleeding, in all the other patients. Four patients successfully underwent repeated TAE for delayed bleeding or increasing hematoma after the initial TAE. The clinical success rate, defined as no need for thoracotomy for hemostasis after TAE, was 92.6%. Five patients underwent post-embolization thoracotomy for hemostasis. No patient developed major TAE-related complications, such as cerebral infarction or quadriplegia. Conclusion TAE is a safe, effective and minimally invasive method for controlling thoracic wall and intrathoracic systemic arterial hemorrhage after thoracic trauma. TAE may be considered for patients with hemothorax without other concomitant injuries which require emergency surgery, or those who undergoing emergency TAE for abdominal or pelvic hemostasis. [ABSTRACT FROM AUTHOR]

A nanocrystalline-Zn-embedded TiOx--amorphous carbon composite was prepared using a two-step high-energy mechanical milling (HEMM) process. First, the starting ZnO was reduced to Zn by Ti incorporation via HEMM. The resulting Zn--TiOx composite was then placed in an amorphous carbon matrix via a second milling step, resulting in a Zn--TiOx--C nanocomposite. The samples were analyzed by X-ray diffraction (XRD), Raman spectroscopy, and X-ray photoelectron spectroscopy; the results confirmed the formation of metallic Zn and amorphous TiOx phases in the composite. The nanocrystalline-Zn-embedded phase and its distribution were observed by high-resolution transmission electron microscopy. The electrochemical reaction mechanism of the Zn--TiOx--C nanocomposite with Li+ during the first cycle was investigated by ex situ XRD analysis. The results demonstrated the reaction sequence of the nanocrystalline Zn phase with Li+ and the electrochemical reactivities of the amorphous TiOx and carbon phases toward Li+. In the electrochemical tests, the Zn--TiOx--C composite showed greatly improved electrochemical properties compared to those of pure Zn. This improvement was attributed to the microstructure of the composite, in which the nanocrystalline Zn was uniformly dispersed, to the TiOx phases, and to the amorphous carbon matrix functioning as buffers against the large volume changes of Zn. [ABSTRACT FROM AUTHOR]

Self-aligned Nb2O5 nanotube (NT) arrays are grown by facile electrochemical anodization at 180°C with an applied bias of 10 V for 10 min in anhydrous glycerol electrolyte. Amorphous Nb2O5 NT arrays can be transformed into pseudo-hexagonal Nb2O5 NT arrays by annealing at 440°C for 20 min in ambient air. Hydrogen treatment of this film was conducted at 440°C for 20 min with flowing 4% H2/96% Ar mixed gas. Hydrogen treatment causes no modification of crystalline properties and hydrogen-treated Nb2O5 (denoted as H2-Nb2O5) NT arrays exhibit no apparent change in the optical bandgap, indicating negligible visible light absorbance. Only small changes in structural properties, such as pore diameter, wall thickness, and chemical state, are observed in the surface region of H2-Nb2O5 NT arrays. However, H2-Nb2O5 NT arrays exhibit a significant increase in electron concentration by the formation of oxygen vacancies, leading to significantly enhanced electronic conductivity. As a result, charge recombination reactions in the interfacial region between H2-Nb2O5 NT arrays and electrolyte are efficiently hindered, resulting in remarkably enhanced photocurrent density in the photoelectrochemical cell. The air-Nb2O5 NT arrays exhibit a photocurrent density of only 0.11 mA/cm²at 1.0 VNHE, while H2-Nb2O5 NT arrays show a significantly increased photocurrent density up to 0.69 mA/cm² at 1.0 VNHE, a more than six-fold improvement in photoelectrochemical performance. [ABSTRACT FROM AUTHOR]

This paper presents a hybrid model solution for user motion recognition. The use of a single classifier in motion recognition models does not guarantee a high recognition rate. To enhance the motion recognition rate, a hybrid model consisting of decision trees and artificial neural networks is proposed. We define six user motions commonly performed in an indoor environment. To demonstrate the performance of the proposed model, we conduct a real field test with ten subjects (five males and five females). Experimental results show that the proposed model provides a more accurate recognition rate compared to that of other single classifiers. [ABSTRACT FROM AUTHOR]

Antimony (Sb)/carbon nanocomposite and Sb/carbon/graphite composite were prepared by high-energy mechanical milling and were investigated as an anode material for Li rechargeable batteries. X-ray diffraction and high-resolution transmission electron microscopy revealed that the Sb/carbon nanocomposite is composed of nanosized Sb and amorphous carbon, and the electrochemical tests showed that it exhibited good electrochemical reversibility and enhanced cyclability. Moreover, the cyclic performance and high-rate capability can be further enhanced by controlling the voltage range or discharge capacity. Also, Sb/carbon/graphite composite showed a high capacity with very good cyclic performance. [ABSTRACT FROM AUTHOR]

A correction to the article "High-Rate Capability and Enhanced Cyclability of Antimony-Based Composites for Lithium Rechargeable Batteries," published in the 2007 issue of the "Journal of the Electrochemical Society".