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In order to provide a sufficient theoretical basis for the fatigue‐resistant design of the aircraft wheels, strain‐controlled low‐cycle fatigue (LCF) tests were carried out on specimens machined in the extrusion direction (ED) and transverse direction (TD) of die‐forged 2014 aluminum alloy wheels. Although the TD specimens have lower tensile strength and yield strength, the fatigue test results show that the TD specimens have superior fatigue life compared with the ED specimens at total strain amplitudes of 0.5–0.8%. This is predominantly caused by the coarse Al12(MnSi)2(FeCu) intermetallic particles close to the surface layer, which results in a relatively short crack initiation stage for the ED specimens. In contrast, TD specimens with finer and more uniform recrystallized grains exhibit more excellent resistance to fatigue crack initiation (FCI) and propagation (FCP). Moreover, the fatigue life of alloys could be accurately predicted via a Manson–Coffin–Basquin (MCB) model based on total strain. Highlights: A new die forging method was used to fabricate the aircraft wheel.Fatigue characteristics and fracture behavior of aircraft wheels were explored.The accuracy of different fatigue life prediction models was evaluated.Coarse Al12(MnSi)2(FeCu) intermetallic particles affected fatigue crack initiation. [ABSTRACT FROM AUTHOR]

Aortic aneurysm (AA) is a serious condition that largely increases the risk of aortic dissection and sudden death. Exploring the global burden of disease and changes in risk factors for AA is essential for public health policy development. To project the death burden from AA and its attributable risk factors in the following decade based on the epidemiological data over the past 30 years. We analysed the death burden of AA and trends of four risk factors from 1990–2019 using the updated 2019 Global Burden of Disease study database by Joinpoint regression analysis. Furthermore, we project the AA-related death burden for the next decade using the Bayesian age-period-cohort model. This study discovered that the global burden of death attributable to AA began to increase after decreasing for two decades. This upward trend will continue in the subsequent decade (average annual percent change: 0.318%, 95% CI: 0.288 to 0.348). Meanwhile, the disease burdens in all economic regions except high-middle socio-demographic index (SDI) regions will continuously increase in the next decade, with the fastest acceleration in the low-middle SDI region (average annual percent change: 1.183%, 95% CI: 1.166 to 1.200). Notably, high systolic blood pressure will surpass the contribution of smoking to become the most important risk factor for mortality due to AA. This study discovered a rebounding trend in the aortic aneurysm-related death burden globally. High systolic blood pressure will be the top risk factor attributed to death from AA. Therefore, it should be considered as the first-degree risk factor in the guidance of AA management and criteria for population-based screening programs. The death burden of aortic aneurysms is beginning to rebound globally, and the trend will continue for the next decade. High systolic blood pressure will replace smoking as the most important risk factor associated with aortic aneurysm death. [ABSTRACT FROM AUTHOR]

A versatile fabrication technique for plasmonic silver (Ag) nanostructures that uses visible light exposure for micropatterning and plasmon resonance tuning is presented. The surface of a glass substrate modified with gold (Au) nanoseeds by a thermal dewetting process was used as a Ag plating platform. When a solution containing silver nitrate and sodium citrate was dropped on the Au nanoseeds under visible light exposure, the plasmon-mediated reduction of Ag ions was induced on the Au nanoseeds to form Ag nanostructures. The plasmon resonance spectra of Ag nanostructures were examined by an absorption spectral measurement and a finite-difference time-domain (FDTD) simulation. Some examples of Ag nanostructure patterning were demonstrated by means of light exposure through a photomask, direct writing with a focused laser beam, and the interference between two laser beams. Surface enhanced Raman spectroscopy (SERS) of 4-aminothiophenol (4-ATP) was conducted with fabricated Ag nanostructures.