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In this paper, we propose generalized inverse power methods with variable shifts for finding the smallest H-/Z-eigenvalue and associated H-/Z-eigenvector of symmetric tensors. The methods are guaranteed to always converge to a H-/Z-eigenpair. Furthermore, for an even order nonsingular symmetric M -tensor, the proposed method with any positive initial point always converges to the smallest H-eigenvalue. Numerical results are reported to illustrate that the proposed methods often can find the smallest H-/Z-eigenvalue instead of other H-/Z-eigenvalues of symmetric tensors. Moreover, we can always get the smallest H-eigenvalue for an even order nonsingular symmetric M -tensor. [ABSTRACT FROM AUTHOR]

China launched its national carbon emissions trading scheme (ETS) in 2017. The choice of allowance allocation methods can strongly influence the political acceptance of an ETS by enterprises/sectors that are covered by it. This article builds a computable general equilibrium model to conduct a quantitative analysis of the effects of nine common allowance allocation methods on both the macro-economy and the industries covered by the ETS. The results of the model show that national gross domestic product (GDP) decreases by 0.37-0.44% during the 13th Five-Year Plan period against a backdrop of a 2% annual reduction in carbon emissions from the sectors covered by the ETS compared with the business-as-usual scenario. China's total emissions drop by 1.71-1.76%. When auctioning and allocation approaches without ex-post adjustment are used, the allowance price is 40-45 yuan/tCO2. When the dynamic allocation methods are used, the allowance price increases to 70-75 yuan/tCO2. Auctioning and allocation approaches without ex-post adjustment exert the same influence on macroscopic indicators (such as GDP and total emissions) and industry indicators (such as output and price). The dynamic allocation methods have a subsidy effect, which can significantly reduce the effect of the ETS on GDP and industry output while significantly increasing the allowance price and decreasing the economic efficiency of the ETS. The cement and steel industries are the most sensitive to the output subsidy effect of the dynamic allocation methods. This article suggests a limit on the use of dynamic allocation approaches to avoid excessively high allowance prices and excessive subsidies for overcapacity industries. [ABSTRACT FROM AUTHOR]

Expression of vascular endothelial growth factor (VEGF) increases in cancer cells during hypoxia. Herein, we report that the MDM2 oncoprotein plays a role in hypoxia-mediated VEGF upregulation. In studying the characteristics of MDM2 and VEGF expression in neuroblastoma cells, we found that hypoxia induced significantly higher upregulation of both VEGF mRNA and protein in MDM2- positive cells than in the MDM2-negative cells, even in cells without wild-type (wt) p53. We found that hypoxia induced translocation of MDM2 from the nucleus to the cytoplasm, which was associated with increased VEGF expression. Enforcing overexpression of cytoplasmic MDM2 by transfection of the mutant MDM2/166A enhanced expression of VEGF mRNA and protein production, even without hypoxia. The results of mechanistic studies demonstrated that the C-terminal RING domain of the MDM2 protein bound to the AU-rich sequence within the 3' untranslated region (3'UTR) of VEGF mRNA; this binding increased VEGF mRNA stability and translation. In addition, knockdown of MDM2 by small interfering RNA (siRNA) in MDM2-overexpressing cancer cells resulted in inhibition of VEGF protein production, cancer cell survival, and angiogenesis. Our results suggest that MDM2 plays a p53-independent role in the regulation of VEGF, which may promote tumor growth and metastasis. [ABSTRACT FROM AUTHOR]

The microgels were prepared by emulsion polymerization of dimethylacrylamide (DMAA), acrylamide (AAm) and 3-acrylamidephenylboronic acid (AAPBA) in water. Based on the microgel matrix, composite hydrogels were polymerized by adding glutaraldehyde to a chitosan (CS) solution. The microgels were uniformly dispersed in the CS polymer network. Scanning electron microscopy (SEM) indicated a spherical structure of the microgel; the size distribution of the microgel was determined with a Zetasizer with the final average particle size of 59.28 nm. The gel was also characterized by Fourier transform infrared spectroscopy (FTIR) and thermogravimetry analysis (TGA). The water swelling, pH sensitivity and glucose sensitivity of the hydrogels were also studied; we found that the composite hydrogels had a certain responsiveness to glucose at physiological pH with a response time of about 50 min. These observations suggest an excellent prospect for the use of the gel as a self-regulated, insulin-delivery system discretely switching the release at the normoglycemia. It lays the foundations for the gel's use in humans for drug delivery. [ABSTRACT FROM AUTHOR]

In this paper, the Hager–Zhang (HZ) conjugate gradient (CG) algorithm is studied for large-scale smooth optimization problems. (i) Some results of the HZ CG method for smooth unconstrained optimization problems are given, and a modified HZ (MHZ) CG method is proposed; (ii) the HZ and MHZ CG methods for nonlinear equations are analysed, the global convergence is established and numerical results for large-scale nonlinear equation problems are reported (1,00,000 variables). [ABSTRACT FROM AUTHOR]

Conjugate gradient methods are widely used for solving unconstrained optimization and nonlinear equations, specially in large-scale cases. Since they own the attractive practical factors of simple computation and low memory requirement, interesting theoretical features of curvature information and strong global convergence. In this paper, we present a modified conjugate gradient algorithm by line search method with acceleration scheme for nonlinear symmetric equations. Furthermore, the proposed method not only possess descent property but also owns global convergence in mild conditions. Numerical results also indicate that the presented method is much more effective than the other methods for the test problems. [ABSTRACT FROM PUBLISHER]

To address the conjugate heat transfer problem in complex geometries, a coupling approach based on the local coordinate transformation is developed to evaluate the common wall temperature on non-orthogonal solid–fluid interfaces. The proposed coupling approach is validated and then used to investigate the erosion-induced shape change effects in a composite nozzle. The changes of flow field are evident in terms of the Mach number, temperature, and pressure, especially in the vicinity of erosion steps. The comparison of the wall pressure distribution indicates that the nozzle thrust performance degrades after erosion. [ABSTRACT FROM PUBLISHER]