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Introduction The incidence of bladder cancer following transplantation is high; however, no previous studies have reported the development of bladder cancer following bone marrow and bilateral lung transplantations. Case presentation A 42‐year‐old man who was followed for bilateral lung transplantation due to chronic graft‐versus‐host disease following bone marrow transplantation complained of gross hematuria. Transurethral resection of the bladder tumor was performed for cT1N0M0 bladder cancer. On the following night, he experienced severe respiratory failure and was intubated. He was discharged on postoperative day 32 with the introduction of home oxygen therapy. The pathological diagnosis was invasive urothelial carcinoma, high‐grade, pT1, with urothelial carcinoma in situ. Further treatment could not be performed because of his poor performance status and immunosuppressive state. Conclusion Vigorous screening for bladder cancer coexisting with other malignancies should be performed for transplant recipients for the early diagnosis and prompt treatment of a relatively aggressive bladder cancer.

Abstract Micro‐speckle patterns were fabricated using α‐Al2O3 and SiC micro‐particles for in‐plane strain distribution measurement at temperatures up to 1500°C using an ultraviolet high‐temperature observation system (UV‐HTOS) combined with a digital image correlation (DIC) technique. The experimental results showed that the measured mean surface strains of α‐Al2O3 were in good agreement with the calculated values obtained from thermal expansion coefficient and temperature difference. The proposed speckle pattern could be used for strain distribution measurement without degradation even after heating up to 1500°C. The results also demonstrated that the pattern fabricated in this study is effective to understand the heterogeneous deformation mechanism in composite materials applied in high‐temperature structural components.

The relationship between morphology (grain-size order) and mechanical properties of Al _x CoCrCuFeNi (x = 0.3 and 1) was evaluated. Both alloys were prepared using the arc-melting method. Crystal structures with x = 0.3, face-centered cubic (FCC), and body-centered cubic (BCC) structures were observed for x = 1, the typical crystal structures of Al _x CoCrCuFeNi. The alloys prepared via arc melting exhibited two different microstructures: a Cu-rich region (area I) and an equiatomic region (area II). Microstructures of the as-fabricated specimen were homogenized through heat treatment at 600 and 1000 °C for 5 h. Although the homogenization of the microstructure proceeded, areas I and II remained after the heat treatment. In particular, the area I composition was inconsistent with the predicted phase diagram. Tensile tests for these alloys revealed that the tensile strength of x = 1 (∼310–1100 MPa) is higher than that of x = 0.3 (∼320–660 MPa), whereas the fracture strain of x = 1 (∼0.03–0.09) is lower than that of x = 0.3 (∼0.06–0.26). These results indicate that the increase in Al content caused an increase in strength and brittle fracture because it also caused an increase in the formation of the BCC and B2 phases, which required higher stresses for the movement of dislocations than the FCC phase. Because the tensile properties of Al _x CoCrCuFeNi are comparable to those of conventional alloys, such as Ti alloys and steels, a design with a moderate composition for stronger and tougher Al _x CoCrCuFeNi is required to apply high entropy alloys to structural materials.

Abstract The pulse thermography (PT) technique was applied to the detection of the delamination of a multi-layered coating system composed of mullite/Si onto a reaction-bonded SiC substrate. The potential evaluation was carried out in order to detect internal delamination in multi-layered material system. Moreover, the observation of the cross sections and 3D views obtained by X-ray computed tomography (CT) indicated that the delamination occurred at the interface between the top coat and the bond coat layers. The changes in the temperature distribution obtained by PT indicated the existence of a delamination area in the top coat layer of the mullite. In particular, the lower temperature region corresponded to the delamination area. The experimental results confirmed that the PT technique is effective with respect to the internal delamination of multi-layered coating system.

Using arc melting, a novel rare-earth silicide, middle entropy Yb–Gd–Ti-Si, was fabricated for high-temperature material applications. The oxidation behavior of the Yb–Gd–Ti-Si was evaluated through oxidation tests conducted at 1200 °C for 1, 2, 4, and 8 h in air. The oxidation rate at 1200 °C was almost the same, regardless of the addition of Ti. The oxidation rate of Yb–Gd–Ti-Si at lower temperatures (600 °C to 900 °C) was lower than that of Yb–Gd–Si. In addition, detailed microstructural observations indicate that the formation of TiO _2 and other oxides in the Yb-Ti–O (Yb–Ti–Si–O) phase suppresses the formation of Yb _2 O _3 , causing a drastic oxidation at intermediate temperatures (600 °C to 900 °C). These results indicate that the addition of Ti to Yb–Gd–Si is effective at preventing the preferential oxidation of the grain boundaries at 600 °C to 900 °C, which is commonly observed in metal silicides.

Carbon-fiber-reinforced ultrahigh-temperature ceramic (C/UHTC) matrix composites are an attractive candidate for fabricating various hot structures. The present study aimed to establish a Si-free Zr–Ti melt-infiltration method for fabricating C/UHTC matrix composites. To achieve this, the wettability of Zr–Ti alloys on carbon and their reactivity to carbon were examined. The alloys were melted on graphite plates and infiltrated into model preforms, which were made of porous carbon and had median pore diameters of 3 μm. The results showed that the apparent contact angle between Zr–Ti and C measured from melted alloys on carbon in room temperature was ~20–42° and that the alloys infiltrated into the preforms regardless of the Zr or Ti content. However, with an increase in the Zr content in the alloys, carbon disappeared and was absorbed into the alloys since the reactivity of Zr was higher than that of Ti and the specific surface area of the porous preform was higher than that of carbon-fiber-reinforced carbon composites, which are a typical preform of C/UHTC matrix composites. These results clearly indicate that not only the capillary flow during infiltration but also the reactivity of alloys to preforms should be considered in the process design for fabricating high-density composites via Zr–Ti infiltration.

Three-dimensional networked porous carbons (TNPCs) exhibit unique structures, and the relationship between the Young's modulus and relative density does not follow the conventional relational expression proposed by Gibson and Ashby. In this study, image analysis for TNPC models developed by reconstructing cross-sectional images obtained via X-ray computed tomography and focused ion beam scanning electron microscopy is conducted to extract the geometric factors of TNPCs, specifically, the strut length (L), struct thickness (t), diameter of the joints (dj), strut aspect ratio (L/t), and strut constriction ratio (dj/t). By evaluating these geometric factors, simple cubic three-dimensional computer-aided design (CAD) models, which reflect the geometric factors of TNPCs, are established to clarify the effect of these factors on the Young's modulus. The results indicate that L/t is the most effective geometric factor to determine the Young's modulus of TNPCs. The relationship between L/t and dj/t, obtained using the cubic CAD models, is in good agreement with that for TNPCs. Therefore, L/t and dj/t can help guide the design for the Young's modulus of porous materials. [ABSTRACT FROM AUTHOR]