Linear and nonlinear optical absorption coefficients in inverse parabolic quantum wells under static external electric field

In the present theoretical study, the linear and third-order nonlinear optical absorption coefficients have been calculated in GaAs/Ga1−xAlxAs inverse parabolic quantum wells (single and double) subjected to an external electric field. Our calculations are based on the potential morphing method in the effective mass approximation. The systematic theoretical investigation contains results with all possible combinations of the involved parameters, as quantum well width, quantum barrier width, Al concentration at each well center and magnitude of the external electric field. Our results indicate that in most cases investigated, the increase of the electric field blue-shifts the peak positions of the total absorption coefficient. In all cases studied it became apparent that the incident optical intensity considerably affects the total absorption coefficient

Podiatrist care and outcomes for patients with diabetes and foot ulcer

We examined whether outcomes of care (amputation and hospitalisation) among patients with diabetes and foot ulcer differ between those who received pre‐ulcer care from podiatrists and those who did not. Adult patients with diabetes and a diagnosis of a diabetic foot ulcer were found in the MarketScan Databases, 2005–2008. Multivariate Cox proportional hazard models estimated the hazard of amputation and hospitalisation. Logistic regression estimated the likelihood of these events. Propensity score weighting and regression adjustment were used to adjust for potentially different characteristics of patients who did and did not receive podiatric care. The sample included 27 545 patients aged greater than 65+ years (Medicare‐eligible patients with employer‐sponsored supplemental insurance) and 20 208 patients aged lesser than 65 years (non Medicare‐eligible commercially insured patients). Care by podiatrists in the year prior to a diabetic foot ulcer was associated with a lower hazard of lower extremity amputation, major amputation and hospitalisations in both non Medicare‐eligible commercially insured and Medicare‐eligible patient populations. Systematic differences between patients with diabetes and foot ulcer, receiving and not receiving care from podiatrists were also observed; specifically, patients with diabetes receiving care from podiatrists tend to be older and sicker.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/109633/1/iwj12021.pd

On the Quantum Confinement Effects in Ultrathin PdO Films by Experiment and Theory

Radio frequency magnetron sputtering conducted in a high vacuum with a base pressure of 1×10−6 mbar was used to deposit ultrathin palladium films on Corning glass. The thickness of these films ranged from 0.4 to 13 nanometers. PdO films were produced after being post-annealed in a furnace at temperatures of 530 degrees Celsius in the presence of air. The results of an atomic force microscopy study showed that the material possessed a high crystalline quality with a low roughness. When looking at Tauc plots to determine the position of the direct optical band gap, the thicker films show a value that is relatively close to 2.2 eV. When the film thickness was reduced all the way down to 0.7 nm, a significant “blue shift” of more than 0.5 eV was observed. In order to provide a more in-depth understanding of the experiment, theoretical calculations based on the Hartree–Fock approximation as applied to an electron-hole system were performed in the framework of the effective mass approximation. The findings are regarded as empirical proof of the existence of quantum confinement effects