Mg-Ni-H films as selective coatings: tunable reflectance by layered hydrogenation

Unlike other switchable mirrors, Mg2NiHx films show large changes in reflection that yield very low reflectance (high absorptance) at different hydrogen contents, far before reaching the semiconducting state. The resulting reflectance patterns are of interference origin, due to a self-organized layered hydrogenation mechanism that starts at the substrate interface, and can therefore be tuned by varying the film thickness. This tunability, together with the high absorptance contrast observed between the solar and the thermal energies, strongly suggests the use of these films in smart coatings for solar applications.Comment: Three two-column pages with 3 figures embedded; RevTE

Randomised controlled trial of integrated care to reduce disability from chronic low back pain in working and private life

Objective To evaluate the effectiveness of an integrated care programme, combining a patient directed and a workplace directed intervention, for patients with chronic low back pain

Structural and optical properties of Mg_xAl_1-xH_y gradient thin films: a combinatorial approach

The structural, optical and dc electrical properties of MgxAl1-x (0.2≤x≤0.9) gradient thin films covered with Pd/Mg are investigated before and after exposure to hydrogen. We use hydrogenography, a novel high-throughput optical technique, to map simultaneously all the hydride forming compositions and the kinetics thereof in the gradient thin film. Metallic Mg in the MgxAl1-x layer undergoes a metal-to-semiconductor transition and MgH₂ is formed for all Mg fractions x investigated. The presence of an amorphous Mg-Al phase in the thin film phase diagram enhances strongly the kinetics of hydrogenation. In the Al-rich part of the film, a complex H-induced segregation of MgH₂ and Al occurs. This uncommon large-scale segregation is evidenced by metal and hydrogen profiling using Rutherford backscattering spectrometry and resonant nuclear analysis based on the reaction ¹H(¹⁵N,αγ)¹²C. Besides MgH₂, an additional semiconducting phase is found by electrical conductivity measurements around an atomic [Al]/[Mg] ratio of 2 (x=0.33). This suggests that the film is partially transformed into Mg(AlH₄)₂ at around this composition

Longitudinal associations between self-reported sleep duration and cardiometabolic disease risk in corporate executives

Objective: This study aimed to determine the longitudinal associations between self-reported sleep duration and cardiometabolic disease (CMD) risk in corporate executives. Methods: Self-reported sleep duration and lifestyle, occupational, psychological, and anthropometrical, blood pressure and blood marker variables were obtained from 1512 employees at annual health risk assessments in South Africa between 2016 and 2019. Gender-stratified linear mixed models, adjusting for age, lifestyle, occupational and psychological covariates were used to explore these longitudinal associations. Results: Among women, shorter sleep duration was associated with higher body mass index (BMI) covarying for age only (ß with 95% confidence intervals: −0.19 [−0.36, −0.03]), age and occupational factors (−0.20 [−0.36, −0.03]) and age and psychological factors (−0.20 [−0.37, −0.03]). Among men, shorter sleep was associated with both BMI and waist circumference (WC) covarying for age only (BMI: −0.15 [−0.22; −0.08]; WC: −0.62 [−0.88; −0.37]); age and lifestyle factors (BMI: −0.12 [−0.21; −0.04]); WC: −0.016 [−0.92; −0.29], age and occupational factors (BMI: −0.20 [−0.22; 0.08]; WC: −0.62 [−0.88; −0.36]), and age and psychological factors (BMI: −0.15 [−0.22; −0.07]; WC: −0.59 [−0.86; −0.33]). Among men, shorter sleep was also longitudinally associated with higher CMD risk scores in models adjusted for age and lifestyle factors (CMD: −0.12 [−0.20; −0.04]) and age and psychological factors (CMD: −0.08 [−0.15; −0.01]). Conclusion: Corporate executives who report shorter sleep durations may present with poorer CMD risk profiles, independent of age, lifestyle, occupational and psychological factors. Addressing sleep health in workplace health programmes may help mitigate the development of CMD in such employees.</p