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Sc as one of the most important microalloying elements in advanced Al alloys has gained tremendous attentions in recent years. The newly identified Sc-rich clusters demonstrate new strengthening effect in Al alloys and thus entail a comprehensive understanding on their phase relationship. In this work, various phase transitions of binary Al–Sc system are systematically investigated by first-principles calculation together with cluster expansion. The results show the phase transition from FCC Al to HCP Sc bypass a BCC structure as a function of Sc concentration. The ordered BCC lattice experiences BCC to FCC, BCC to HCP and BCC to ω phase transitions through the Bain, Burgers and ω phase transition paths, respectively. The possibility of those phase transitions is evaluated from the calculated energy landscape along the transition paths. BCC to FCC and BCC to ω phase transitions are energetically more favorable in Al–Sc system. The bonding electron density and effective cluster interaction suggests the Al–Sc interactions play a key role in individual phase transition at different Sc concentration.

Though high-capacitance transition metal oxides are considered as promising pseudocapacitive materials to achieve high-energy storage for supercapacitors, the practical capacitance is far from the theoretical values because of their intrinsic poor abilities about the electronic and ionic transports. Here, to tackle these problems, we develop a hybrid nanostructured electrode in a facile process, in which layer-structured δ-MnO2 nanosheets are anchored onto seamless three-dimensional Ni nanocylinder arrays. The resultant Ni/δ-MnO2 nanocylinder arrays exhibit high specific capacitance up to 883.2 Fg−1 at a scan rate of 10 mVs−1 and achieve high energy density about 108 Whkg−1 at a power of 2.4 kWkg−1. The improved electrochemical performance mainly benefits from the vertically aligned Ni/δ-MnO2 hybrid structure. Owing to such a hybrid structure the ion/electron transports are facilitated along the nanocylinders due to the reduction in the transport distance, and large accessible surface area is also provided for anchoring more high-capacitance materials. Moreover, the additional contact resistance can be dramatically reduced owing to the large interplanar spacing of δ-MnO2 and ordered semicoherent interface of Ni/δ-MnO2. Keywords: Supercapacitor, Hybrid electrode, Ni nanocylinder arrays, δ-MnO2, 3D nanostructure

Background: Remnant cholesterol (RC) contributes to residual risk of atherosclerotic cardiovascular disease, but population-based evidence on the prospective relationship between RC and coronary artery calcium (CAC) progression is rare., Methods: We pooled data obtained from 6544 atherosclerotic cardiovascular disease-free individuals from the CARDIA study (Coronary Artery Risk Development in Young Adults; n=2635) and MESA (Multi-Ethnic Study of Atherosclerosis; n=3909), with a mean±SD age of 47.2±19.8 years; 3019 (46.1%) were men who completed computed tomography of CAC at baseline. RC was measured as total cholesterol minus HDL (high-density lipoprotein) cholesterol minus calculated LDL (low-density lipoprotein) cholesterol (LDL-C) estimated by using the Martin/Hopkins equation. Adjusted Cox models were used to assess the relationships between RC levels and CAC progression. We also performed discordance analyses examining the risk of CAC progression in RC versus LDL-C discordant/concordant groups using median cut points and clinically relevant LDL-C targets., Results: During a median follow-up of 8.6 years, 2778 (42.5%) participants had CAC progression. After multivariable adjustment for demographics and cardiovascular risk factors, a 1-mg/dL increase in RC levels was associated with a 1.3% higher risk of CAC progression (hazard ratio, 1.013 [95% CI, 1.008-1.017]). Results were similar when we categorized individuals by RC quartiles. Furthermore, the discordant high RC/low LDL-C group had a significantly higher risk of CAC progression than the concordant low RC/LDL-C group regarding their medians (hazard ratio, 1.195 [95% CI, 1.063-1.343]) or when setting the clinical LDL-C cut points at 100 and 130 but not 70 mg/dL. The association remained robust across a series of sensitivity analyses., Conclusions: Elevated RC levels were associated with an increased risk of CAC progression independent of traditional cardiovascular risk factors, even in individuals with optimal LDL-C levels., Registration: URL: https://www., Clinicaltrials: gov; Unique identifiers: NCT00005130 (CARDIA) and NCT00005487 (MESA).

Objective: To investigate whether low-carbohydrate diets (LCDs) were associated with coronary artery calcium (CAC) progression. Approach and Results: We included the participants who completed computed tomography assessment of baseline CAC in 2000 to 2001 (year 15) and follow-up (year 20 or 25) and food frequency questionnaire (years 0, 7, and 20) in the CARDIA study (Coronary Artery Risk Development in Young Adults). CAC progression was defined as CAC >0 at follow-up among participants with baseline CAC of 0 and an annualized change of 10 or percent change of ≥10% for those with 0