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The use of ceramic–metal laminated composites is an efficient way to improve the toughness of brittle ceramics. Uniform multilayered Al2O3–Ni laminated composites were prepared through a combined method of gel casting and hot pressing, which is less cumbersome than the traditional sequential lamination method. The wettability, diffusion and chemical reaction between Al2O3 and Ni were controlled through surface oxidation treatment of the Ni sheets. The results show that when the surface-oxidized Ni sheets were used, the microstructure of the Al2O3–Ni interface changed with the hot-pressing temperature. As the hot-pressing temperature was increased from 1150 to 1300 °C, a straight and clean interface formed, the interface became interlocked and, finally, a stable layer of NiAl2O4 formed at the interface. The interlocked microstructure was especially beneficial for interfacial bonding, and the plastic deformation of the Ni layers was restrained, thereby leading to slip steps rather than dimple formation on the fracture surfaces of the Ni layers. In addition, the toughening effects of plastic deformation and crack deflection in the Al2O3–Ni laminated composites were significant, which resulted in ductile fracture rather than brittle fracture. As a result, the Al2O3–Ni laminated composite that was prepared using the oxidized Ni sheets and the combined method of gel casting and hot pressing achieved a higher work of fracture than laminated composites that were prepared via other methods. [ABSTRACT FROM AUTHOR]

Ag/Y2O3 has excellent potential to replace Ag/CdO as the environmentally friendly electrical contact material. Using spherical Y2O3 as the starting material, Ag/Y2O3 contacts with a quasi-continuous network structure were successfully fabricated by a low-energy ball milling treatment. The mean size of Y2O3 used ranged from 243 to 980 nm. Due to the differences in the size of Y2O3, Ag/Y2O3 contacts had different primitive microstructures, thereby exhibiting distinctive anti-arc-erosion capabilities. Ag/Y2O3 contact prepared using 243 nm Y2O3 showed the best anti-arc-erosion capability and the most outstanding electrical performance measures, such as low contact resistance, less mass transfer, and no failure up to 105 cycle times. The quasi-continuous network structure formed in the micro-scale was responsible for the excellent electrical performance. The short distance between Y2O3 particles in the network promoted the cathode arc motion, and thus alleviated the localized erosion. The results obtained herein may inspire further attempts to design electrical contacts rationally. [ABSTRACT FROM AUTHOR]

Osteoarthritis (OA) is a common joint disease caused by progressive articular cartilage degeneration and destruction. Currently, there are no disease-modifying agents officially approved for OA patients. In this study, curcumin was loaded into adipose tissue-derived mesenchymal stem cells (ADMSCs)-derived small extracellular vesicle (ADMSCs-sEV) to synergistically exert chondro-protective effects in vitro and in vivo. We found curcumin primed ADMSCs derived sEV (sEV-CUR) exhibited an enhanced protective effect compared with free curcumin and ADMSCs-sEV in TBHP-induced chondrocytes. Moreover, our study demonstrated sEV-CUR more effectively down-regulated TBHP-induced oxidative stress and chondrocyte apoptosis in vitro. In OA mice model, our results indicated that sEV-CUR showed an improved cartilage protection, as biweekly intra-articular injection of sEV-CUR more efficaciously alleviated oxidative stress and chondrocyte apoptosis in OA cartilage. Overall, our findings showed sEV-CUR exhibited enhanced chondro-protective effects and holds great potential on the recovery of articular cartilage loss and destruction in OA patients. [ABSTRACT FROM AUTHOR]

Background: This study aimed to explore the anatomical correlation between the femoral neck shaft angle (NSA) and femoral anteversion angle (AA) in patients with developmental dysplasia of the hip based on the Crowe classification and provide a novel method to estimate the femoral AA on anteroposterior pelvic radiographs.Methods: A total of 208 patients with dysplastic hips who underwent total hip arthroplasty at our institution were retrospectively included. Preoperative physiological AA and NSA were determined via 3-dimensional computed tomography. Linear regressions and Pearson's coefficients were calculated to assess the correlation between the femoral NSA and femoral AA.Results: A total of 416 hips were divided into 5 subgroups: 99 normal, 143 type I, 71 type II, 63 type III, and 40 type IV hips following the Crowe classification. Dysplastic femurs had significantly higher AAs than normal hips (25.2° vs 31.4° vs 33.3° vs 35.5° vs 41.7°). Significant positive correlations between the AA and NSA were observed in normal (r = 0.635), type I (r = 0.700), type II (r = 0.612), and type III (r = 0.638) hips (P < .001); however, no meaningful correlation was observed in type IV hips (r = 0.218, P = .176).Conclusion: The NSA and AA correlated positively and significantly in the normal and dysplastic Crowe type I-III hips. The relationship between the NSA and AA indicates torsion of the proximal femur and offers an opportunity for straightforward estimation of AA based on NSA. [ABSTRACT FROM AUTHOR]

Background: Accumulating evidence indicates that long non-coding RNAs (lncRNAs) are involving in the tumorigenesis and metastasis of lung cancer. The aim of the study is to systematically characterize the lncRNA-associated competing endogenous RNA (ceRNA) network and identify key lncRNAs in the development of stage I lung adenocarcinoma (LUAD).Methods: Totally, 1,955 DEmRNAs, 165 DEmiRNAs and 1,107 DElncRNAs were obtained in 10 paired normal and LUAD tissues. And a total of 8,912 paired lncRNA-miRNA-mRNA network was constructed. Using the Cancer Genome Atlas (TCGA) dataset, the module of ME turquoise was revealed to be most relevant to the progression of LUAD though Weighted Gene Co-expression Network Analysis (WGCNA).Results: Of the lncRNAs identified, LINC00639, RP4-676L2.1 and FENDRR were in ceRNA network established by our RNA-sequencing dataset. Using univariate Cox regression analysis, FENDRR was a risk factor of progression free survival (PFS) of stage I LUAD patients (HRs = 1.69, 95%CI 1.07-2.68, P < .050). Subsequently, diffe rential expression of FENDRR in paired normal and LUAD tissues was detected significant by real-time quantitative (qRT-PCR) (P < 0.001).Conclusions: This study, for the first time, deciphered the regulatory role of FENDRR/miR-6815-5p axis in the progression of early-stage LUAD, which is needed to be established in vitro and in vivo. [ABSTRACT FROM AUTHOR]