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A new approach based on combination of cell-center finite volume method (C-C FVM) and Timoshenko beam theory has been developed to analyze static and free vibration of functionally graded beams in this paper. The general dynamic equations for under uniformly load functionally graded beam (FGB) are derived using Hamilton’s principle, and the equations can be simplified for static bending or free vibration problem. Governing equations are discretized by C-C FVM in spatial space. In the analysis, three different kinds of shear correction factors are considered and material properties are assumed to vary continuously by power-law along the thickness. To validate the accuracy of the numerical method, the deflection and natural frequencies of FGB are studied. Good agreement is achieved between present results and literatures for different boundary conditions, shear correction factors, material distribution and span-depth ratios. Furthermore, the optimal shear correction factor is obtained by comparing three different kinds of shear correction factors and the no shear locking phenomenon in static analysis is presented. [ABSTRACT FROM AUTHOR]

Human papillomaviruses (HPVs) cause a subset of head and neck squamous cell carcinomas (HNSCCs). Previously, we demonstrated that HPV16 oncogene E6 or E6/E7 transduction increases the abundance of O-linked β-N-acetylglucosamine (O-GlcNAc) transferase (OGT), but OGT substrates affected by this increase are unclear. Here, we focus on the effects of O-GlcNAcylation on HPV-positive HNSCCs. We found that upon HPV infection, Unc-51-like kinase 1 (ULK1), an autophagy-initiating kinase, is hyper-O-GlcNAcylated, stabilized, and linked with autophagy elevation. Through mass spectrometry, we identified that ULK1 is O-GlcNAcylated at Ser409, which is distinct from the previously reported Thr635/Thr754 sites. It has been demonstrated that PKCα mediates phosphorylation of ULK1 at Ser423, which attenuates its stability by shunting ULK1 to the chaperone-mediated autophagy (CMA) pathway. Using biochemical assays, we demonstrate that ULK1 Ser409Ser410 O-GlcNAcylation antagonizes its phosphorylation at Ser423. Moreover, mutations of Ser409A and its neighboring site Ser410A (2A) render ULK1 less stable by promoting interaction with the CMA chaperone HSC70 (heat shock cognate 70 kDa protein). Furthermore, ULK1-2A mutants attenuate the association of ULK1 with STX17, which is vital for the fusion between autophagosomes and lysosomes. Analysis of The Cancer Genome Atlas (TCGA) database reveals that ULK1 is upregulated in HPV-positive HNSCCs, and its level positively correlates with HNSCC patient survival. Overall, our work demonstrates that O-GlcNAcylation of ULK1 is altered in response to environmental changes. O-GlcNAcylation of ULK1 at Ser409 and perhaps Ser410 stabilizes ULK1, which might underlie the molecular mechanism of HPV-positive HNSCC patient survival. [ABSTRACT FROM AUTHOR]

Abstract: A new approach based on cell vertex finite volume method (CV-FVM) has been developed by the introduction of the staggered grid technique for thermoelastic analysis in functionally graded materials (FGMs). The 4-node quadrilateral grid and the 3-node triangular grid are employed to deal with mixed-grid problems. The performance of the developed method has been demonstrated by four numerical tests. First, the consideration of the bilinear quadrilateral grid is found to be important for the elimination of artificial numerical oscillation in the displacement field. Second, the staggered grid technique is proved (within the considered test cases) to be efficient and reliable for thermoelastic analysis in FGMs without any undesirable discontinuous distribution. Third, the present method requires small computational and memory costs compared to the method adopting graded elements or higher-order theory. [Copyright &y& Elsevier]

A blockchain-based smart contract has the potential to allow the performance of credible transactions without third parties. This paper presents a universal framework for a blockchain platform that enables peer-to-peer (P2P) energy trading in the retail electricity market. Focusing attention on seeking energy-matching pairs from the supply and demand sides, and encouraging direct energy trading between producers and consumers, the P2P energy trading mechanism is proposed. The designed multidimensional blockchain platform implements a complete energy trading process. As smart contracts strictly execute the trading and payment rules without human interaction, the security and fairness of energy trading are significantly enhanced. Case studies in the Ethereum private chain demonstrate that the proposed mechanism has obvious advantages in reflecting market quotations, balancing profits of players, and facilitating the utilization of renewables. Based on such characteristics, players are incentivized to participate in the P2P energy trading. Moreover, the authentic gas consumption and computational time to the smart contract indicate that this platform is able to achieve an efficient and effective transaction with multi-player participation. • This paper presented a P2P energy trading mechanism with the double auction. • A universal blockchain platform for decentralized energy trading was proposed. • The designed smart contract provides secure and automatic energy trading services. • Simulation results showed the feasibility and efficiency of the proposed platform. [ABSTRACT FROM AUTHOR]

• Vapor bubble dynamics during boiling affected by surface acoustic wave (SAW) for the first time. • Numerical simulation by coupling phase field method and thermo-viscous acoustic module. • SAW creates 'micro-turbulence' around boiling bubble and accelerates the bubble detachment. • SAW breaks the thermal boundary layer near the heating surface and greatly lower the surface temperature. • SAW can serve as an active method for control and enhancement of boiling heat transfer. In this study, the dynamic mechanism of vapor bubble during boiling process under the effect of acoustic field was numerically investigated, by coupling the phase field method and thermo-viscous acoustic module. The purpose is to use the surface acoustic wave (SAW) to interfere with vapor bubbles in the boiling process, so as to realize control of boiling on the temporal and spatial scales while improving the boiling heat transfer capability. It is observed that the effect of SAW on bubble behaviors is related to the amplitude of SAW and the initial bubble size. For pool boiling case, at the critical displacement amplitude, tiny vortices form at the root of bubble during the bubble growth stage. The velocity amplitude induced by SAW in the liquid phase around bubble can reach up to 2.1 m/s, which is nearly twofold comparing to that without SAW effect. The vortices at the root of bubble disrupt the thermal boundary layer to a certain extent by creating 'micro-turbulence', thereby reducing the thermal resistance. Furthermore, the strong SAW effect for the large amplitude case causes one bubble to collapse into two separate bubbles after the bubble detaches from the heating surface. For flow boiling case, the SAW can break the growing bubbles along the flow direction, and the collapsed bubbles flow downstream with a maximum speed of 5 m/s, which is almost 12.5 times of that without acoustic excitation. The acoustic streaming can interrupt the growth of the boundary layer in the single-phase region, so that the subcooled fluid can rewet the microchannel wall in time. Thus, the growth of bubbles and flow instability are effectively inhibited, and flow boiling heat transfer is promoted. It is revealed that the SAW is an effective approach for the active control and enhancement of boiling heat transfer. [ABSTRACT FROM AUTHOR]

Highlights: [•] A new numerical approach for structural–acoustic coupling problems is presented. [•] It is capable of the heterogeneous system with irregular region. [•] The effects of the variation of water depth on an enclosed cavity are discussed. [•] The present method is validated to be accurate. [ABSTRACT FROM AUTHOR]

Abstract: To investigate the effects of sanitation processing on the lignification of few-flower wildrice (FFW), fresh-cut FFW was treated with water (control), 80mg/L peroxyacetic acid (PAA), 100mg/L ClO2 or 50mg/L H2O2, packed in polyethylene film bags and stored at 2°C for 21days. Firmness, lignin, cellulose, hemicellulose and lignin forming related enzymes activities were examined. Sanitizer treatments inhibited the increases of firmness, lignin and cellulose than the control. The changes of hemicelluloses did not show a difference between the control and PAA treatment. An increase in the activities of phenylalanine ammonia lyase (PAL), peroxidase (POD) and polyphenol oxidase (PPO), and a reduction in catalase (CAT) and superoxide dismutase (SOD) activities, were detected in the sliced FFW in the incompatible interaction. Compared with the control, sanitizers suppressed the activities of PAL, POD and PPO, but enhanced the activities of SOD and CAT during 21days of storage. These enzymatic activities varied with different sanitizers. These results show that 80mg/L peroxyacetic acid (PAA), 100mg/L ClO2 or 50mg/L H2O2 sanitation processing can maintain tenderness, alleviate the lignification and fibrosis of fresh-cut FFW. [Copyright &y& Elsevier]

• Utilizing a quasi-thermal equilibrium setup, the temperature dependence of the surface/interfacial properties of liquids (ultra-pure water and aqueous surfactant solutions) are studied. • The thermodynamic model based on modified coefficients can well describe the general trends of surface tension and contact angle changes. • Three different stages, named spreading-controlled Stage I , evaporation-controlled Stage II , and depinning-controlled Stage III are found for the dynamic evolution of surfactant-laden droplet. The surface/interfacial properties of liquid at elevated temperatures are fundamental issues for wide applications where the surface force matters. The dynamic characteristics of wetting behavior and surface tension (ST) of surfactant solutions remain unclear at thermal equilibrium, especially at high temperature. Utilizing a quasi-thermal equilibrium setup, the temperature dependence of the surface/interfacial properties of liquids (ultra-pure water and aqueous surfactant solutions) at temperature ranging from 10 to 90 °C (1 atm) are studied, by the sessile drop method and pendant drop method, respectively. A decreasing trend of the initial ST and contact angle (CA) is observed with the increase of temperature. During evaporation, the increase of the local relative humidity around the droplet has a crucial influence on CA. The obtained ST and CA are based on the thermodynamic model with modified coefficients, which can well describe the general trends for different temperatures and concentrations. For the ultra-pure water, the droplets will be pinned suddenly on the heating surface, until a sudden contraction occurs with evaporation. However, the surfactant-laden droplet shows different dynamical behaviors from ultra-pure water. Three different stages, named spreading-controlled Stage I , evaporation-controlled Stage II , and depinning-controlled Stage III are found for the dynamic evolution of surfactant-laden droplet. In what follows, the different droplet behaviors are also analyzed for surfactant solution and ultra-pure water. [ABSTRACT FROM AUTHOR]