Carburization was performed for Ti–46.5Al (at%) alloy at different temperature (870, 900, 930, and 960 °C) for different time (2, 4, and 6 h) to improve its corrosion resistance. Anodic polarization ...curves, electrochemical impedance spectroscopy (EIS), and the SEM morphology of the corroded samples were investigated to evaluate corrosion resistance of the carburized TiAl alloy in 1 M HCl. The results reveal that the carburized samples at 900 °C for 6 h show the noblest pitting potential, the lowest current density, the highest impedance value, and the largest phase angle compared with the other carburized samples. The corroded surface of the carburized TiAl alloy at 900 and 930 °C for 6 h after anodic polarization in 1 M HCl presents a very compact deposited layer. Therefore, the carburized TiAl alloy at 900 °C for 6 h exhibits most excellent corrosion resistance.
Insulin resistance is a key feature of obesity and type 2 diabetes mellitus (T2DM). Interaction of insulin with the insulin receptor (IR) leads to both its auto-phosphorylation and phosphorylation of ...tyrosine residues on the IR substrate (IRS) proteins, initiating the activation of intracellular signaling cascades. The metabolic effects of IRS are known to be mediated through pathways involving phosphatidyl-inositol 3-kinase (PI-3K), which result in the activation of Akt signaling. The C-terminal region of the IR ectodomain is required to facilitate the conformational changes that are required for high-affinity binding to insulin. Furthermore, the CH2 and CH3 domains in the Fc fragments of immunoglobulins are responsible for their binding to the Fc receptor, which triggers transcytosis. In this study, we created a fusion peptide of the C-terminal end of the human IR ectodomain with the IgG4 Fc fragment, including an intervening polyG fragment to ensure enough space for insulin binding. We named this new peptide "Yiminsu", meaning an insulin sensitizer. The results of our analyses show that Yiminsu significantly facilitates insulin signaling via the activation of Akt in hepatocytes in a dose- and time-dependent manner. Further studies are required to determine whether Yiminsu can act as an insulin sensitizer.
Silver nanorods have been prepared by an electrochemical technique from an aqueous solution of AgNO
3 in the presence of polyethylene glycol (PEG). The silver nanorods were characterized by using ...transmission electron microscopy, X-ray diffraction, and absorption spectroscopy. It was found that the concentration of AgNO
3 and PEG affected the formation of the nanorods.
Nanocomposites of thermally stable polybenzimidazole (PBI) containing small amounts (<1%) of functionalized multi-walled carbon nano-tubes (CNT) are prepared using solution casting methods. These PBI ...and PBI/CNT composites are doped with potassium hydroxide (KOH) solution to prepare hydroxide-conducting electrolytes for alkaline direct methanol fuel cell (ADMFC) applications. The CNT-containing composites exhibit higher fractional free volumes and higher water diffusivities. CNT also promotes ionic conductivity of electrolytes and improves the fuel cell performance. Gas diffusion electrodes (GDEs) without polytetrafluoroethene (PTFE) treatment give superior cell power density compared to commercial E-tek GDEs, which contain hydrophobic PTFE layers. When the fuel cell is fed with 2 M methanol in 6 M KOH (as the anode fuel) and humidified oxygen (as the cathode oxidant), the system achieves a maximum power density of 104.7 mW cm super(-2) at 90 degree C. These KOH-doped PBI/CNT composites have the potential to be used in high temperature alkaline fuel cell applications.
Background
Biomarkers have been related to the arrhythmia recurrence following catheter ablation (CA) of atrial fibrillation (AF). We hypothesized that concurrent measurement of several biomarkers ...would additively improve their predictive value.
Methods
One thousand four hundred and ten consecutive AF patients (68% male; 57.2 ± 11.6 years) undergoing CA were enrolled. Baseline characteristics, serum B type brain natriuretic peptide (BNP) and high sensitivity C reactive protein (hsCRP), estimated glomerular filtration rate (eGFR), ablation parameters, arrhythmia data at discharge, 1, 3, 6, and then every 6 months post CA were collected. Follow‐up ended when arrhythmia recurred or until 31st December 2016.
Results
Three hundred and sixty‐five (25.9%) patients had arrhythmia recurrence post‐CA during a mean follow‐up of 20.7 ± 8.8 months. BNP, hsCRP, and eGFR levels and their cut‐off values of 237.45 pg/mL, 1.6 mg/dL, and 82.5 mL/min/1.73 m2 were good predictors for AF recurrence (all P < 0.01). On multivariate analysis, increasing BNP and hsCRP, decreasing eGFR, gender, and early recurrence (ER) were independent predictors of AF recurrence (all P < 0.01). Compared to BNP alone, BNP plus eGFR or both eGFR and CRP showed incrementally better predictive values (ROC comparisons, all P < 0.01). Similar findings were evident in the subgroups of patients with paroxysmal or nonparoxysmal AF.
Conclusion
Measurement of BNP, CRP, and eGFR were incrementally additive to clinical risk factors in a cumulative manner to improve prediction of arrhythmia recurrence post‐CA of AF. The implications of poor arrhythmia outcome in AF patients with multiple abnormal biomarkers pre‐CA procedure may help with patient selection and inform the likelihood of success or the need of more complicated CA procedure(s).
The bulk-quantity synthesis of single-crystal GaN nanowires has been achieved through a simple method of hot filament chemical vapor deposition without using a nanometer-sized catalyst. The ...microstructures and optical properties of GaN nanowires have been studied by electron microscopy and photoluminescence (PL) measurements at room temperature. The GaN nanowires had diameters of 5–12 nm and lengths of a few micrometers, and were highly pure. They possessed a hexagonal wurtzite structure and had a growth direction perpendicular to the {11̄01} plane. The PL spectra showed a broad emission peak centered at 420 nm.
The protein encoded by the first gene of the triple gene block (TGBp1) of potexviruses is required for movement of the viruses. It has been reported that single Arg-->Ala substitutions at position ...11, 16 or 21 of TGBp1 of Bamboo mosaic virus (BaMV) eliminate its RNA-binding activity, while substitutions at position 16 or 21 only affect its NTPase activity (Liou et al., Virology 277, 336-344, 2000). However, it remains unclear whether these Arg-->Ala substitutions also affect the movement of BaMV in plants. To address this question, six mutants of BaMV, each containing either a single- or a double-alanine substitution at Arg-11, Arg-16 and Arg-21 of TGBp1, were constructed and used to infect Chenopodium quinoa and Nicotiana benthamiana. We found that all of the BaMV mutants were able to replicate in protoplasts of N. benthamiana. However, only the mutant with an Arg-11-->Ala substitution in TGBp1 remained capable of movement from cell to cell in plants. Mutants with Arg-16, Arg-21 or both Arg-16 and Arg-21 of TGBp1 replaced with alanine were defective in virus movement. This defect was suppressed when a wild-type TGBp1 allele was co-introduced into the cells using a novel satellite replicon. The ability to trans-complement the movement defect by the wild-type TGBp1 strongly suggests that the Arg-->Ala substitution at position 16 or 21 of TGBp1, which diminishes the RNA-binding and NTPase activities of TGBp1, also eliminates the capability of BaMV to move from cell to cell in host plants.
Surgical site infection (SSI) is the most common infectious complication after emergency abdominal surgery (EAS). To a large extent, most SSI can be prevented, but there are few relevant studies in ...China. This study mainly investigated the current situation of SSI occurrence after EAS in China, and further explored risk factors for SSI occurrence.
Multi-center cross-sectional study was conducted. Clinical data of patients undergoing EAS in 33 hospitals across China between May 1, 2019 and June 7, 2019 were prospectively collected, including perioperative data and microbial culture results from infected incisions. The primary outcome was the incidence of SSI after EAS, while the secondary outcomes were postoperative hospital stay, ICU occupancy rate, length of ICU stay, hospitalization cost, and mortality within postoperative 30 days. Univariate and multivariate logistic regression models were used to analyze the risk factors of SSI after EAS.
A total of 660 EAS patients aged (47.9±18.3) years were enrolled in
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