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This paper proposes a directly self-starting second-order s -sub-step explicit method, within which the three novel members are developed and analyzed for demonstration. The novel explicit schemes can output second-order accelerations for general structures, which cannot be achieved for the directly self-starting single- and two-sub-step algorithms. Each explicit algorithm achieves controllable algorithmic dissipation and adjustable bifurcation points. As a result, the novel explicit algorithms impose two algorithmic parameters, ρ b and Ω b , to control numerical dissipation and bifurcation point, respectively. The parameter ρ b , denoting the spectral radius at the bifurcation point, controls numerical dissipation, whereas the parameter Ω b , denoting the bifurcation point, adjusts the amount of dissipation imposed in the low-frequency range. This paper provides users with two recommended selections of Ω b . Apart from these desirable features, each novel explicit algorithm attains the maximum stability bound, 2 × s where s denotes the number of sub-steps. The four- and five-sub-step algorithms perform optimization to reduce numerical low-frequency dissipation. As the number of sub-steps increases, the novel explicit algorithms can have better numerical characteristics without an increase in the computational effort. Numerical examples are simulated to validate the performance and superiority of the novel explicit algorithms. [ABSTRACT FROM AUTHOR]

With the wide application of thermoelastic structures in industries such as the aerospace field, the problem of topology optimization of thermoelastic structures has become a very common and important research topic. It is well known that the thermal environment has a non‐negligible influence on the dynamic performance of structures. However, few people consider the influence of the thermal environment on structural stiffness in thermoelastic dynamic topology optimization. In practical engineering applications, the influence of the environment on the structure performance should be considered to obtain the optimal structure. In this paper, we focus on the problem of dynamic topology optimization considering the effect of non‐uniform temperature fields on structural stiffness. The influence of non‐uniform temperature fields adds on structural stiffness to the topology optimization of thermoelastic dynamic for the first time, thereby comprehensively addressing its effects on structural stiffness in the context of dynamic topology optimization under harmonic vibration and transient load. The proposed method begins by computing the distribution of the non‐uniform temperature field within the structure. Subsequently, thermal stresses in the structure are determined through the application of thermoelastic theory. The geometric stiffness matrix of the structure is then calculated using finite element theory. The dynamic topology optimization model, employing a variable density approach, is established in conjunction with the dynamic compliance design objective. Sensitivity analysis is conducted through the adjoint method, and the design variables are updated utilizing the method of moving asymptotes. Numerical examples are presented to validate the efficacy of the proposed method and obtain the influence of different factors on the optimization results. The results show that the dynamic compliance of the optimized structure increases with increasing heat flux. For the optimization under harmonic vibration, the optimization results obtained by different external excitation frequencies are significantly different. For transient optimization, the study discovers that the optimization present transient effect. [ABSTRACT FROM AUTHOR]

Advanced glycation end‐products (AGEs), formed endogenously or obtained exogenously from diet, may contribute to chronic inflammation, intracellular signaling alterations, and pathogenesis of several chronic diseases including colorectal cancer (CRC). However, the role of AGEs in CRC survival is less known. The associations of pre‐diagnostic circulating AGEs and their soluble receptor (sRAGE) with CRC‐specific and overall mortality were estimated using multivariable‐adjusted Cox proportional hazards regression among 1369 CRC cases in the European Prospective Investigation into Cancer and Nutrition (EPIC) study. Concentrations of major plasma AGEs, Nε‐[carboxy‐methyl]lysine (CML), Nε‐[carboxy‐ethyl]lysine (CEL) and Nδ‐[5‐hydro‐5‐methyl‐4‐imidazolon‐2‐yl]‐ornithine (MG‐H1), were measured using ultra‐performance liquid chromatography mass‐spectrometry. sRAGE was assessed by enzyme‐linked immunosorbent assay. Over a mean follow‐up period of 96 months, 693 deaths occurred of which 541 were due to CRC. Individual and combined AGEs were not statistically significantly associated with CRC‐specific or overall mortality. However, there was a possible interaction by sex for CEL (Pinteraction =.05). Participants with higher sRAGE had a higher risk of dying from CRC (HRQ5vs.Q1 = 1.67, 95% CI: 1.21–2.30, Ptrend =.02) or any cause (HRQ5vs.Q1 = 1.38, 95% CI: 1.05–1.83, Ptrend =.09). These associations tended to be stronger among cases with diabetes (Pinteraction =.03) and pre‐diabetes (Pinteraction <.01) before CRC diagnosis. Pre‐diagnostic AGEs were not associated with CRC‐specific and overall mortality in individuals with CRC. However, a positive association was observed for sRAGE. Our findings may stimulate further research on the role of AGEs and sRAGE in survival among cancer patients with special emphasis on potential effect modifications by sex and diabetes. [ABSTRACT FROM AUTHOR]

Furfural is a renewable platform compound that can be derived from lignocellulosic biomass. The highly functionalized molecular structure of furfural enables us to prepare a variety of high value-added chemicals, which will help realize biomass high-value utilization, and alleviate energy and environmental problems. This paper reviews the research progress on furfural production and upgrading to C5 chemicals from the catalyst perspective. The emphasis is placed on summarizing and refining the catalytic mechanism and in-depth analysis of available data. Specifically, the reaction mechanism of furfural production and upgrading is summarized firstly from the perspective of reaction pathways and reaction kinetics. Then, the available data are further processed to evaluate the actual reaction efficiency of different catalytic systems from multiple dimensions. Finally, based on statistical analysis, the challenges and opportunities of furfural-based research are proposed. [ABSTRACT FROM AUTHOR]

The catalytic activity of platinum for CO oxidation depends on the interaction of electron donation and back‐donation at the platinum center. Here we demonstrate that the platinum bromine nanoparticles with electron‐rich properties on bromine bonded with sp‐C in graphdiyne (PtBr NPs/Br‐GDY), which is formed by bromine ligand and constitutes an electrocatalyst with a high CO‐resistant for methanol oxidation reaction (MOR). The catalyst showed peak mass activity for MOR as high as 10.4 A mgPt−1, which is 20.8 times higher than the 20 % Pt/C. The catalyst also showed robust long‐term stability with slight current density decay after 100 hours at 35 mA cm−2. Structural characterization, experimental, and theoretical studies show that the electron donation from bromine makes the surface of platinum catalysts highly electron‐rich, and can strengthen the adsorption of CO as well as enhance π back‐donation of Pt to weaken the C−O bond to facilitate CO electrooxidation and enhance catalytic performance during MOR. The results highlight the importance of electron‐rich structure among active sites in Pt‐halogen catalysts and provide detailed insights into the new mechanism of CO electrooxidation to overcome CO poisoning at the Pt center on an orbital level. [ABSTRACT FROM AUTHOR]