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Gd-doped ceria ͑GDC͒-impregnated ͑La 0.75 Sr 0.25 ͒͑Cr 0.5 Mn 0.5 ͒O 3 ͑LSCM͒ is investigated as an alternative Ni-free anode for the direct utilization of methane in solid oxide fuel cells. Impregnation of submicrometer and ionic conducting GDC greatly improves the electrocatalytic activity of the LSCM anodes for the oxidation reaction in weakly humidified ͑3% H 2 O͒ methane. At 800°C, electrode polarization resistance for the reaction in wet CH 4 is 0.44 ⍀ cm 2 on a 4.0 mg cm −2 GDC-impregnated LSCM anode. In comparison, the electrode polarization resistance is 11.4 and 8.1 ⍀ cm 2 on a pure LSCM and a LSCM ͑50 wt %͒/yttria-stabilized zirconia ͑YSZ͒ ͑50 wt %͒ composite anode, respectively, under the same testing conditions. The polarization performance of GDC-impregnated LSCM is also substantially higher than that of the pure LSCM and LSCM/YSZ composite anodes. Based on the results, a mechanism involving the dry reforming of methane, followed by the electrochemical oxidation of the dry reforming products is proposed for the methane oxidation on Ni-free mixed ionic and electronic conductors such as LSCM. Impregnation of nanosized GDC greatly enhances the catalytic as well as electrochemical activities for the dry reforming of methane and for the electrochemical oxidation reactions of the dry reforming products.

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In a magnetic shape memory alloy system, we vary composition following phenomenological arguments to tune macroscopic properties. We achieve significantly higher shift in austenite to martensitic phase transition temperature with magnetic field. This enhancement is accompanied by significant broadening of the transition and by field-induced arrest of kinetics, both of which are related to the dynamics of the coexisting phases. This reveals hitherto unknown interrelationship between different length-scales. This may serve as an effective route for comprehensive understanding of similar multicomponent systems which show considerable variation in physical properties by minor change in microscopic parameters.

Epithelial–mesenchymal transition (EMT) is a crucial step in tumor progression, and the TGFβ–SMAD signaling pathway as an inductor of EMT in many tumor types is well recognized. However, the role of non-canonical TGFβ–TAK1 signaling in EMT remains unclear. Herein, we show that TAK1 deficiency drives metastatic skin squamous cell carcinoma earlier into EMT that is conditional on the elevated cellular ROS level. The expression of TAK1 is consistently reduced in invasive squamous cell carcinoma biopsies. Tumors derived from TAK1-deficient cells also exhibited pronounced invasive morphology. TAK1-deficient cancer cells adopt a more mesenchymal morphology characterized by higher number of focal adhesions, increase surface expression of integrin α5β1 and active Rac1. Notably, these mutant cells exert an increased cell traction force, an early cellular response during TGFβ1-induced EMT. The mRNA level of ZEB1 and SNAIL, transcription factors associated with mesenchymal phenotype is also upregulated in TAK1-deficient cancer cells compared with control cancer cells. We further show that TAK1 modulates Rac1 and RhoA GTPases activities via a redox-dependent downregulation of RhoA by Rac1, which involves the oxidative modification of low-molecular weight protein tyrosine phosphatase. Importantly, the treatment of TAK1-deficient cancer cells with Y27632, a selective inhibitor of Rho-associated protein kinase and antioxidant N-acetylcysteine augment and hinders EMT, respectively. Our findings suggest that a dysregulated balance in the activation of TGFβ–TAK1 and TGFβ–SMAD pathways is pivotal for TGFβ1-induced EMT. Thus, TAK1 deficiency in metastatic cancer cells increases integrin:Rac-induced ROS, which negatively regulated Rho by LMW-PTP to accelerate EMT.

We study through the time evolution of magnetization the low-temperature (T) dynamics of the metastable coexisting phases created by traversing different paths in magnetic field H and T space in a shape memory alloy system, Ni 45 Co 5 Mn 38 Sn 12 . It is shown that these coexisting phases consisting of a fraction of kinetically arrested austenite phase and a remaining fraction of low-T equilibrium martensitic phase undergo a slow relaxation to low magnetization (martensitic) state but with very different thermomagnetic history-dependent rates at the same T and H. We discovered that, when the nucleation of the martensitic phase is initiated at much lower T through the de-arrest of the glasslike arrested state contrasted with the respective first-order transformation (through supercooling at much higher T), the long-time relaxation rate scales with the nonequilibrium phase fraction but has a very weak dependence on T. This is explained on the basis of the H-T path dependent size of the critical radii of the nuclei and the subsequent growth of the equilibrium phase through the motion of the interface.