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• A new alloy Ni-Co-Cr-Hf-C was designed for laser powder bed fusion (LPBF). • Laser remelting of a cast substrate was used to mimic LPBF conditions. • An ultra-fine dispersion of stable nano-sized HfC particles was obtained. • The mean particle diameter is 54 nm with an interparticle distance of 325 nm. The dispersion of stable nano-particles is essential for improving the high temperature creep properties of Ni-base alloys. Additive manufacturing by laser powder bed fusion (LPBF) offers novel means to tailor particle distributions taking advantage of the fast and directional solidification inside travelling melt pools. To benefit of this opportunity, a novel in-situ carbide reinforced alloy Ni − 32Co − 28Cr − 3.5Hf − 0.25C (wt. %) was developed. In a first rapid approach laser remelting of a cast alloy block was used to mimic LPBF solidification conditions. After a subsequent annealing treatment at 1150 °C for 6 h, an ultra-fine and intragranular dispersion of nano-sized HfC particles was obtained. The HfC particles have an average size of 54 nm and a mean inter-particle distance of 326 nm, which is an exceptional refinement compared to the as-cast microstructure. The number density of HfC particles ranges around 1 × 1012/m2 in 2D and is estimated to be 2 × 1019/m3 in 3D. [ABSTRACT FROM AUTHOR]

Aims To investigate retinal nerve fibre layer ( RNFL) thickness in people with metabolic syndrome (MetS) and healthy controls. Methods A cross-sectional study was performed from March 2014 to January 2016. All participants underwent anthropometric and serological biochemical measurements, ophthalmological examination, and spectral-domain optical coherence tomography ( SD- OCT). Individuals with elevated intraocular pressure, glaucoma, diabetic retinopathy and other ocular disorders were excluded. T-test, Chi square and general linear models were used to analyse the data. Results In total, 278 eyes from 139 participants were investigated [median (interquartile range) age: 37 (32−43) years]. RNFL thickness was lower in the nasal superior (107.8 ± 19.5μm) and temporal superior (135.7 ± 18.9μm) sectors in MetS group compared with the control group (114.6 ± 22.4 μm, P = 0.013 and 140.7 ± 18.2 μm, P = 0.027, respectively). After multiple adjustments for age, gender and the side of the examined [right ( OD)/left ( OS)] eye, MetS was independently associated with a lower RFNL thickness in the nasal superior (β = 0.20, P = 0.009) and temporal superior (β = 0.14, P = 0.048) sectors. RNFL thickness was significantly reduced in participants with higher numbers of metabolic abnormalities, independent of age, gender and the side of the examined eye ( P = 0.043). Conclusion Our findings demonstrate that MetS is independently associated with reduced RNFL thickness, suggesting that neurodegeneration is implicated in pathogenesis of MetS. [ABSTRACT FROM AUTHOR]