GaAs1−yBiy Raman signatures: illuminating relationships between the electrical and optical properties of GaAs1−yBiy and Bi incorporation

We report the use of two Raman signatures, the Bi-induced longitudinal-optical-plasmon-coupled (LOPC) mode and the GaAs Fröhlich scattering intensity, present in nominally undoped (100) GaAs1−yBiy to predict the 300K photoluminescence intensity and Bi composition (y) in GaAs1−yBiy. The LOPC mode is used to calculate the hole concentration in GaAs1−yBiy epitaxial layers. A linear relationship between hole concentration and photoluminescence intensity is found for a range of samples grown at various temperatures and growth rates. In addition, the composition (y) of Bi in GaAs1−yBiy is also found to be linearly related to the GaAs Fröhlich scattering intensity

Reliability of a portable device for quantifying tone and stiffness of quadriceps femoris and patellar tendon at different knee flexion angles.

The reliability of MyotonPRO that can monitor the mechanical properties of tissues is still unclear. This study aimed to analyze the within-day inter-operator and between-day intra-operator reliability of MyotonPRO for assessing tone and stiffness of quadriceps femoris and patellar tendon at different knee angles. The tone and stiffness of healthy participants (15 males and 15 females, aged 24.7±1.6 years) in the supine and resting position were measured using the MyotonPRO device. The measurements were quantified at 0°, 30°, 60°, and 90° of knee flexion. The intraclass correlation coefficient (ICC), standard error of measurement (SEM), and minimal detectable change (MDC) were calculated and a Bland-Altman analysis was conducted to estimate reliability. The results indicated excellent inter-operator reliability (ICC > 0.78) and good to excellent intra-operator reliability (ICC > 0.41). The inter-operator SEM measurements ranged between 0.1-0.9 Hz and 3.8-37.9 N/m, and intra-operator SEM ranged between 0.5-1.3 Hz and 7.9-52.0 N/m. The inter-operator MDC ranged between 0.3-2.5 Hz and 10.5-105.1 N/m, and intra-operator SEM ranged between 1.1-3.3 Hz and 21.9-144.1 N/m. The agreement of inter-operator was better than that of intra-operator. The study concluded that MyotonPRO is a reliable device to detect the tone and stiffness of quadriceps femoris and patellar tendon

Enhanced Activity and Stability of TiO₂‑Coated Cobalt/Carbon Catalysts for Electrochemical Water Oxidation

TiO₂-coated Co/C catalysts prepared by atomic layer deposition (ALD) were used to study the effect of TiO₂ overcoating on a Co/C catalyst for electrochemical water oxidation. The Co/C catalyst with a thin-layer overcoating of TiO₂ (ALD­(TiO₂)-Co/C) demonstrated 2.5 times higher turnover frequency (TOF) than the Co/C catalyst for the reaction. The TOF of the ALD­(TiO₂)-Co/C catalyst increased when the ALD­(TiO₂) coating cycle number was increased from 5 to 60. In addition, the stability of the 60 cycle ALD­(TiO₂)-Co/C catalyst was enhanced compared to the Co/C catalyst. This work shows how the ALD synthesis technique can be used to improve the catalytic activity and stability of nonprecious-metal-based catalysts like Co/C for electrochemical water oxidation

Surface Decoration of Peptide Nanoparticles Enables Efficient Therapy toward Osteoporosis and Diabetes

A versatile surface decoration strategy to efficiently encapsulate water-soluble peptides is developed. By assembling peptide molecules into nanoparticles, diverse physiochemical properties of these compacted molecules are equalized to the surface properties of nanoparticles. Primarily driven by the generic electrostatic attractions, the surface of as-prepared peptide nanoparticles is decorated with charged amino acids-grafted poly(lactic-co-glycolic acid). This adsorbed polymer layer versatilely blocks the phase transfer of peptide nanoparticles by increasing their affinity to the dispersed phase solvent molecules. Attributed to the ultrahigh encapsulation efficiencies (> 96%), the peptide mass fraction inside the obtained microcomposites is higher than 48%. The plasma calcium level has been efficiently reduced for ≈3 weeks with only one single injection of salmon calcitonin-encapsulated microcomposite in osteoporotic rats. Similarly, one single injection of exenatide-encapsulated microcomposites efficiently controls the glycemic level in type 2 diabetic rats for up to 3 weeks. Overall, the developed versatile surface decoration strategy efficiently encapsulates peptides and improves their pharmacokinetic features, regardless of the molecular structure of peptide cargos