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To improve the corrosion resistance of LA43M alloy, MgAl-NO3−-Layered Double Hydroxides (LDH) was prepared on the surface of the alloy by an in situ hydrothermal method, and uniform and dense MgAl-V2O74−-LDH films were successfully obtained by ion-exchange over different times. SEM, XRD, EDS, electrochemical polarisation, EIS and hydrogen evolution experiments were conducted to analyse microstructure and corrosion resistance of these films. The results verified that with increase of the ion-exchange reaction time, the nanosheets of the MgAl-V2O74−-LDH film are larger in size, uniformly distributed, and slightly increased in thickness. The surface of the modified MgAl-V2O74−-LDH film grown for 4 h on the surface had a staggered and tilted manner, and the gaps between the nanosheets were small, making it more effective in blocking the corrosive medium. The MgAl-NO3−-LDH film modified by V2O74− anion intercalation can further improve the corrosion resistance of the LA43M alloy. [ABSTRACT FROM AUTHOR]

The question of how to better prepare ethnic minority students to access higher music education has raised concerns around the world in terms of educational equity and cultural diversity. In China, despite similar concerns, little is known about the preparation process and experiences of ethnic minority students to take the Music College Entrance Examination (MCEE). In this qualitative case study, we investigated the facilitators and barriers faced by 22 high school students of Yi, Mongolian and Tibetan backgrounds while preparing for the MCEE in a multi-ethnic school in Sichuan province, southwestern China. The methods included participant observation and semi-structured interviews. The facilitators identified in the study were support from family members, local teachers’ devotion, positive peer influences and nationally renowned ethnic musicians as role models. The five main barriers were financial difficulties, parents’ misconception of the value of the MCEE, limited expertise of local music teachers, exam-oriented school climate and the MCEE’s structure based on Western classical music. Based on the findings, suggestions for adopting affirmative action and reforming the structure of the MCEE are proposed. [ABSTRACT FROM AUTHOR]

Mitochondrial DNA (mtDNA) copy number (CN) is a biomarker of mitochondrial function and has been reported associated with kidney disease. However, its association with IgA nephropathy (IgAN), the most common cause of glomerulonephritis (GN), has not been evaluated. We included 664 patients with biopsy-proven IgAN and measured mtDNA-CN in peripheral blood by multiplexed real-time quantitative polymerase chain reaction (RT-qPCR). We examined the associations between mtDNA-CN and clinical variables and found that patients with higher mtDNA-CN had higher estimated glomerular filtration rate (eGFR) (r = 0.1009, p =.0092) and lower serum creatinine (SCr), blood urea nitrogen (BUN), and uric acid (UA) (r=−0.1101, −0.1023, −0.07806, respectively, all p values <.05). In terms of pathological injury, mtDNA-CN was higher in patients with less mesangial hypercellularity (p =.0385, M0 vs. M1 score by Oxford classification). Multivariable logistic regression analyses also showed that mtDNA-CN was lower for patients with moderate to severe renal impairment (defined as eGFR < 60 mL/min/1.73 m2) vs. mild renal impairment, with the odds ratio of 0.757 (95% confidence interval: 0.579–0.990, p =.042). In conclusion, mtDNA-CN was correlated with better renal function and less pathological injury in patients with IgAN, proposing that systemic mitochondrial dysfunction may be involved in or reflect the development of IgAN. [ABSTRACT FROM AUTHOR]

Cross-border regional innovation systems (CBRIS) have emerged as a key concept in innovation studies, but there have been few successful CBRIS in practice. In this paper we focus on asymmetry in the distribution of benefits as a potential barrier for the development of CBRIS based on an in-depth analysis of collaborative activities in the development of Hong Kong–Shenzhen innovation system. Our analysis reveals that Shenzhen companies are more active than their Hong Kong counterparts in driving the cross-border linkages, are better at leveraging cross-border university resources and have more success in attracting cross-border financial capital. [ABSTRACT FROM AUTHOR]

The interface characteristics and formation mechanism of explosive welded waveform structures still lack a detailed and in-depth research. Thus, a combination of advanced characterization and numerical simulation methods were performed in this study to investigate the phase constitution, texture distribution, 3D interface morphology and wave formation mechanism of Sn/Cu explosive welded interface. The microstructure analyses indicated that the typical waveform structures composed of fine crystal band and elongated grains zone were formed at the Sn/Cu joining interface. The dynamic recrystallized structures and local high strain at the waveform were attributed to severe rheological deformation and rapid solidification of liquid metals. In addition, the S, copper, brass and fiber deformation textures and the cube and gross recrystallization textures were found. The CT results indicated the 3D Sn/Cu joining interface morphology presents a regular convex waveform feature, which is related to periodic pulse load caused by explosive detonation. Furthermore, based on the simulation results, the 2D joining interface presents similar experimental waveform structure, and the 3D interface evolution characteristic was consistent with the shock wave propagation characteristics on the flying plate to some extent, which was in good agreement with the experimental results. [ABSTRACT FROM AUTHOR]

We compared the differences and explored the associations between ethnic identity and Chinese national identity, and the intergroup attitudes of adolescents from the Yi, Han, and Mongolian ethnicities in a Yi ethnic autonomous region in China. The participants (N = 1830, 50% female) were middle school students (n = 910, Mage = 13.51) and high school students (n = 920, Mage = 17.71). We found (a) significant ethnic differences between the high school students in the subscales of behavior, self-identification, and achievement; (b) that the three ethnic groups exhibited nonsignificant differences in their perceptions of Chinese national identity; (c) a positive association between ethnic identity and Chinese national identity for the adolescents across ethnicities; (d) a positive association between ethnic identity and intergroup attitudes for the Yi adolescents only; and (e) that Chinese national identity was positively associated with intergroup attitudes for the Yi and Han adolescents and for the Mongolian middle school students, but not for the Mongolian high school students. This suggests that age and context play central roles in shaping the ethnic and national identities of adolescents in such regions, and those who grow up in an inclusive environment are more likely to develop positive intergroup attitudes. [ABSTRACT FROM AUTHOR]

The stainless steel/Ti/low-carbon steel trimetallic composite plate was successfully fabricated by the explosive welding technique using honeycomb aluminum structure low detonation velocity emulsion explosive. The interfacial microstructure characterizations, elemental distribution, phase transformation and hardness were characterized using optical microscopy (OM), scanning electron microscopy (SEM), electron backscattered diffraction (EBSD) and micro-hardness tester. The results indicated that the trimetallic sheet of stainless steel/Ti/low-carbon steel was successfully welded without visible defects and have an excellent bonding quality. The Ti/;ow-carbon steel joining interface had a typical wavy structure and formed about 3 µm thick transition layer. The stainless steel/Ti joining interface had an almost flat structure; meanwhile, the phase transformation of Fe and Ti and the texture occurred at the joining interfaces. The hardness increased near the welding interface and sharply increased in the melted zones. [ABSTRACT FROM AUTHOR]

The carbon nanotubes doping with Fe and Fe3C nanocrystal (CNTs@Fe/Fe3C) are successfully synthesized by the gas-liquid detonation (GLD) decomposition of CH4, O2, C10H10Fe and C10H8. The composition and structural properties of the as-obtained composites were investigated by XRD, TEM, XPS and Raman spectroscopy. The obtained composites were also applied to the electric double-layer capacitor. The results showed that the specific capacitance of CNTs@Fe/Fe3C can reach 125 F·g−1 at the current density of 100 mA·g−1 and after 10000 cycles the capacitance retention is 93.1% at a current density of 2 A·g−1. [ABSTRACT FROM AUTHOR]

Probabilistic stability analyses of constructed wrapped-face reinforced slopes (or embankments) using frictional soils were carried out using the random finite element method (RFEM). Soil properties reported in the literature for unsaturated frictional fills compacted to different densities were used in the simulations. Bar elements were added to the RFEM code to simulate extensible geosynthetic reinforcement layers and the Davis approach was used to improve numerical stability for purely frictional soil slopes at collapse. The influence of isotropic and anisotropic spatially variable soil strength was investigated and shown to have a large influence on the variation of maximum mobilised tensile forces in reinforcement layers for the steep 5 m-high slopes in the study. The influence of fill placed at different layer thickness and compacted to different levels was simulated by adjusting the soil strength and unit weight, and the vertical strength correlation length in the anisotropic spatially variable strength field used in each slope realisation. Numerical results showed that vertical strength correlation lengths approaching the magnitude of fill lift heights can control the probability of failure for reinforced slopes constructed with weak fills placed in lift heights close to but less than the wrapped reinforcement spacing used in the study. [ABSTRACT FROM AUTHOR]

The 2D random finite element method and the one-dimensional and 2D random limit equilibrium method are used to investigate the influence of spatial variability of soil strength parameters on the probability of failure of simple soil slopes with cohesive undrained shear strength. The combined influence of spatial variability of soil properties and cross-correlation between undrained soil strength and unit weight on the computed probability of failure is explored. The paper identifies conditions where numerical outcomes are similar and where they are not. The limitations of each analysis method are described and implications to analysis and design are identified. Abbreviations:FEM: finite element method; LEM: limit equilibrium method; RFEM: random finite element method; RLEM: random limit equilibrium method [ABSTRACT FROM PUBLISHER]

The carbon nanotubes (CNTs) and CNTs doping with Fe based composites were rapid fabricated by gaseous detonation decomposition of oxygen, benzene and ferrocene mixed precursors. A series of novel experiments were designed to investigate the condensation and formation of carbon structural nanomaterials. The TEM, EDS, EDX, XRD and Raman characterizations provide fundamental evidence of the high yield and purity of the CNTs, CNTs doping with Fe composites during the gaseous detonation reaction process. The results showed that CNTs, CNTs with Fe based nanocrystals, spherical CCFNPs and their mixed products are with variant morphologies. The obtained CNTs is multi-walled carbon nanotubes and CNTs doping with a body-centered cubic iron or iron carbide cores, which can be obtained respectively through adjusting and controlling the detonation reaction environment and the precursors. [ABSTRACT FROM AUTHOR]

Context: Recent ecological evidence has showed a lag-correlation between the prevalence of diabetes and consumption of niacin (nicotinamide and nicotinic acid) in the US. Nicotinamide has been demonstrated to induce insulin resistance due to excess reactive oxygen species and methyl depletion, whereas the effect of nicotinic acid is poorly understood. Objective: To examine the mechanism of the effect of nicotinic acid on glucose metabolism. Materials and methods: Rats were injected with different cumulative doses of nicotinic acid (0.5, 2, 4 g/kg) and nicotinamide (2 g/kg). A glucose tolerance test was given 2 h after the final injection. The role of methyl consumption and reactive oxygen species generation were evaluated by measuring N1-methylnicotinamide and hydrogen peroxide. Results: Cumulative doses of nicotinic acid produced a dose-dependent increase in the plasma levels of N1-methylnicotinamide and hydrogen peroxide, which was associated with a decrease in liver and skeletal muscle glycogen levels. At the same dosage (2 g/kg), in comparison with nicotinamide, nicotinic acid was weaker in raising plasma N1-methylnicotinamide levels (0.7 ± 0.11 µg/mL vs. 4.69 ± 0.24 µg/mL, P < 0.001), but stronger in increasing plasma hydrogen peroxide levels (1.88 ± 0.07 µmol/L vs. 1.55 ± 0.05 µmol/L, P < 0.001). Moreover, nicotinamide, unlike nicotinic acid, did not reduce liver glycogen levels. Discussion and conclusion: This study suggested that excessive nicotinic acid, like nicotinamide, might induce methyl consumption, oxidative stress and insulin resistance. Long-term consumption high niacin may increase the risk of type 2 diabetes. [ABSTRACT FROM AUTHOR]