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The existence of microvascular invasion (MVI) formation is one of the most important risk factors predicting poor outcome in hepatocellular carcinoma (HCC) and its mechanism remains largely unknown. Epithelial-Mesenchymal Transition (EMT) has been suggested to be involved in many steps of the invasion-metastasis cascade. To elucidate the possible contribution of EMT to MVI, we initially evaluated the expression of 8 EMT-related transcription factors (TFs) in HCC patients with or without MVI and found that FOXC1 expression was significantly higher in patients with MVI than those without MVI (P < 0.05). Knockdown of FOXC1 expression in HCC cells resulted in a partial conversion of their EMT progresses, mainly regulating the mesenchymal component. Ectopic expression of snail, twist or TGF-β1 could induce expression of FOXC1, but none of the expression of snail, twist, slug or TGF-β was consistently down-regulated in response to FOXC1 silencing, suggesting FOXC1 might operate the downstream of other EMT regulators. In addition, knockdown of FOXC1 expression led to cytoskeleton modification accompanied by decreased ability of cell proliferation, migration, and invasion. Meanwhile, some matrix metalloproteinases (MMPs) and VEGF-A were also simultaneously down-regulated. Together, our findings demonstrate that FOXC1 is one of candidate predictive markers of MVI, and that inhibition of FOXC1 expression can partially reverse EMT program, offering a potential molecular therapeutic target for reducing tumor metastasis in HCC patients.

The copresence of ferroelectricity and ferromagnetism inside the same compound is a rather scarce phenomenon, and therefore, the development of room-temperature multiferroic materials is a great challenge. In the present work, La0.5Y0.5FeO3 ceramics with La and Y ions partially ordered as a rocksalt type structure have been prepared. Such ordering leads to a polar P21nm phase, which is consistent with a particular type of hybrid improper ferroelectricity that has rarely been observed. Saturated polarization-electric field loops are determined at room-temperature with a remnant polarization of 0.11 μC/cm2, together with a room-temperature predominantly antiferromagnetic order accompanied by a weak magnetization, which renders our La0.5Y0.5FeO3 ceramics an example of a room-temperature multiferroic compound. [ABSTRACT FROM AUTHOR]

Dielectric strength and energy storage density in Ba6−3xLa8+2xTi18O54 (x = 0.5, 2/3, and 0.75) ceramics were investigated as functions of composition and microstructure. With increasing x, although the dielectric constant decreased from 113 to 102, the energy storage density increased from 2.3 J/cm3 to 3.2 J/cm3 due to the increased dielectric strength for ceramics prepared by conventional sintering. The energy storage was further improved to 4.2 J/cm3 in ceramics prepared by spark plasma sintering under an electric field of 1058 kV/cm. Both dielectric strength and energy storage density in the present ceramics indicated the strong processing and microstructure dependence. The optimum dielectric strength and energy storage density were achieved in the dense ceramics with fine grains, while both dielectric strength and energy storage density decreased in the ceramics with coarse columnar grains. [ABSTRACT FROM AUTHOR]

Abstract: CaTiO3 is a typical linear dielectric material with high dielectric constant, low dielectric loss, and high resistivity, which is expected as a promising candidate for the high energy storage density applications. In the previous work, an energy density of 1.5 J/cm3 was obtained in CaTiO3 ceramics, where the dielectric strength was only 435 kV/cm. In fact, the intrinsic dielectric strength of CaTiO3 is predicted as high as 4.2 MV/cm. Therefore, it should be a challenge issue to enhance the dielectric strength and energy storage density of CaTiO3 ceramics by optimizing the microstructures. In the present work, dense CaTiO3 ceramics with fine and uniform microstructures are prepared by spark plasma sintering, and the greatly enhanced dielectric strength (910 kV/cm) and energy storage density (6.9 J/cm3) are obtained. This can be ascribed to the improved resistivity and thermal conductivity, associated with the fine and uniform microstructures. The different post‐breakdown features of CaTiO3 ceramics prepared by different process well interpret why the enhanced dielectric strength is achieved in the SPS sample. The energy storage density can be further improved to 11.8 J/cm3 by introducing the amorphous alumina thin films as the charge blocking layer, where the dielectric strength is 1188 kV/cm. [ABSTRACT FROM AUTHOR]

In this article, electromagnetic bulging of high-strength, low-conductivity Ti-6Al-4V using a T3 copper driver plate at room temperature was described. The investigation was conducted employing numerical simulation method. Numerical prediction of the deformation contour and thickness distribution were closely correlated with the experimental results. The distribution of electromagnetic force on the driver plate and impact force between the driver plate and the workpiece varying with time was obtained. Besides, deformation velocity distribution and strain rate on the workpiece were determined by analyzing the deformation process. Energy efficiency of the process was determined to be 1.34%. Distribution of total electromagnetic force over time is characteristic of a sine-squared attenuation function. Velocity of the second impact near the center zone is 229.36 m/s with a corresponding impact pressure of 3.42 GPa. The results of this investigation are significant in the design of an improved process of electromagnetic forming of Ti-6Al-4V and other low-conductivity metals. [ABSTRACT FROM AUTHOR]