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Herein, the self-assembled formation of AlN nanowires (NWs) by molecular beam epitaxy on sputtered TiN films on sapphire is demonstrated. This choice of substrate allows growth at an exceptionally high temperature of 1180 °C. In contrast to previous reports, the NWs are well separated and do not suffer from pronounced coalescence. This achievement is explained by sufficient Al adatom diffusion on the substrate and the NW sidewalls. The high crystalline quality of the NWs is evidenced by the observation of near-band-edge emission in the cathodoluminescence spectrum. The key factor for the low NW coalescence is the TiN film, which spectroscopic ellipsometry and Raman spectroscopy indicate to be stoichiometric. Its metallic nature will be beneficial for optoelectronic devices using these NWs as the basis for (Al,Ga)N/AlN heterostructures emitting in the deep ultraviolet spectral range.

The utilization of cardiovascular rehabilitation (CR) programmes in patients with Lower Extremity Peripheral Artery Disease (LEPAD) is generally poor, with limited evidence of current policies for referral. The aim of the study was to evaluate, within a cohesive network of CR and vascular surgery facilities with facilitated referral process, the clinical characteristic of LEPAD patients referred to CR and related outcomes, as compared to patients not referred. The present is an observational prospective study of consecutive patients recruited at vascular surgery facilities. Out of 329 patients observed, the average referral rate to CR was 34% (28% and 39% in patients with and without recent peripheral revascularization, p<0.05). LEPAD patients entering the CR programme were similar to those who did not according to sex, age, the vascular surgery setting of evaluation, and localization of arterial lesions. Patients with moderate intermittent claudication and patients with acute limb ischemia as index event were more represented among those who attended CR (41% vs 21% and 9% vs 2% respectively, p<0.05). Patients referred to CR had five times more episodes of acute coronary syndrome and heart failure as complication of the index event. The cardiovascular risk profile (obesity 29.5% vs 11%, p<0.05; hypercholesterolemia 80% vs 61%, p<0.05) was much worse in LEPAD patients referred to CR, but conversely, they better achieved secondary prevention targets, particularly for blood pressure control (97% vs 57%, p<0.05). All-cause 2-year mortality in the whole patients' population was 6%. Patients entering the CR programme displayed less events (13.5% vs 37.7%, p<0.05), mainly death (3.1% vs 11.3%, p<0.05) and limb-related events (4.2% vs 15.2%, p<0.05). The results of our study suggest that when a cohesive network of vascular surgery and CR facilities becomes available, the referral rate to rehabilitation may increase up to one third of eligible patient

Here we report on our study to quantitatively describe the intensities of the valence band hard x-ray photoemission spectra (HAXPES) of a rare earth element containing 3d transition metal oxides. Using LaCoO3 as a representative model compound, we compared the experimental data to the results of ab initio one-step photoemission band structure calculations as well as to the sum of the partial density of states of the atomic constituents weighted by their tabulated photoionization cross sections. We discovered that the semicore La 5p density of states surprisingly contributes in a significant manner to the valence band spectrum: Although the La 5p partial density of states in the valence band region is negligible compared to that of the O 2p or the Co 3d, the La 5p cross section in the hard x-ray range is found to be orders of magnitude larger than that of the other subshells. This explains the long-standing issue of why the hard x-ray valence band spectra of a rare-earth element containing materials have line shapes that are very different from those taken at lower photon energies and why they cannot be described in terms of partial density of states of the subshells usually considered for the lower photon energy spectra. We infer that the contribution of the rare-earth 5p must be taken into account and cannot be ignored.

The growth of Bi on both the In-terminated (A) face and the As-terminated (B) face of InAs(111) has been investigated by low-energy electron diffraction, scanning tunnelling microscopy, and photoelectron spectroscopy using synchrotron radiation. The changes upon Bi deposition of the In 4d and Bi 5d(5/2) photoelectron signals allow to get a comprehensive picture of the Bi/InAs(111) interface. From the early stage the Bi growth on the A face is epitaxial, contrary to that on the B face that proceeds via the formation of islands. Angle-resolved photoelectron spectra show that the electronic structure of a Bi deposit of approximate to 10 bi-layers on the A face is identical to that of bulk Bi, while more than approximate to 30 bi-layers are needed for the B face. Both bulk and surface electronic states observed are well accounted for by fully relativistic ab initio calculations performed using the one-step model of photoemission. These calculations are used to analyse the dichroic photoemission data recorded in the vicinity of the Fermi level around the (Gamma) over bar point of the Brillouin zone.