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Cu-1.3Cr alloys with directional pore structure were fabricated under hydrogen atmosphere. The pore morphology during the solidification is investigated. It is found that the porosity is increased from 18% to 44% and the average pore diameter was decreased from 3.24 mm to 0.44 mm when the hydrogen pressure varies from 0.1 MPa to 0.6 MPa. Theoretical analysis shows the gas pore pressure drops significantly during the growth of pore. For a coarse pore, the drops of pore pressure will result in a backflow of the melt from solidification interface into gas pore, and this will result in a “bamboo” like structure. For small gas pores, the pressure difference between two neighboring gas pores drives the hydrogen gas from the short one to the long one. This is the reason that a short pore more easily coalesce with a long pore.

The LCMO: Ag0.2 thin film was grown on the tilted LAO substrate by pulsed laser technology. The structural and electrical properties of the thin film were studied with different deposition times. The X-Ray diffraction analysis demonstrated that all film samples showed exhibit mixed growth and have high crystalline quality. The surface morphology of the films was characterized by atomic force microscopy, and the surface roughness of the films decreased as the deposition time increased. Electrical properties tests show that the peak voltages Up of LIV signals of the films reach their maximum at a deposition time of 10 min, while it also having the TCRmax = 18.43%·K−1. The testing results show that the presence of optimal film thickness can enhance the anisotropic Seebeck coefficient of the film, which in turn improves the film properties. [ABSTRACT FROM AUTHOR]

We reported the synthesis, characterization, electrical transport, and magnetic properties of polycrystalline La0.7Ca0.24Na0.06MnO3:Agy (LCNMO:Agy) with y = 0.0, 0.1, 0.2, 0.3, and 0.4. The combination of EDS and XPS proved that Ag not only entered the perovskite phase structure but there would also be a small amount of Ag enrichment at the grain boundaries. The magnetoresistance (MR) and temperature coefficient of resistivity (TCR) improved significantly with the addition of Ag as a dopant. At y = 0.2, a multi-functional perovskite material with high TCR (30.57% K−1) near room temperature and large MR (72.28%) at the low magnetic field (1 T) was obtained. This enhancement of MR and TCR near room temperature was attributed to the good connectivity between the grains and the decrease in electron scattering at the grain boundaries. Overall, these findings look promising for future applications in infrared detection bolometers. [ABSTRACT FROM AUTHOR]

Abstract Background The peroxisome proliferator-activated receptor-γ (PPARγ) agonist rosiglitazone has been suggested to exert cardiovascular protection through the improvement of lipid metabolism, anti-inflammation, anti-proliferation etc. However, whether renin-angiotensin system (RAS) is involved in the vascular protective effects of PPARγ agonists is not fully understood. The present study aimed to investigate the effects of the renin-angiotensin system in vascular protection mediated by PPARγ agonists. Objective To investigate the actions of the renin-angiotensin system in vascular protection mediated by activation of PPARγ in vivo and in vitro. Methods Rats were fed a regular diet (n = 8), a cholesterol-rich diet plus methylthiouracil (80 mg/Kg/day, n = 10), a cholesterol-rich diet plus methylthiouracil and rosiglitazone (4 mg/kg/day, n = 10). The rosiglitazone treatment was started from one month after the start of cholesterol-rich diet plus methylthiouracil, and lasted five months. Cultured vascular smooth muscle cells (VSMCs) were pretreated with 1 μmol/L angiotensin II (ANG II) for 6 h and randomly divided into the control group; the ANG II group (1 μmol/L ANG II); the groups respectively treated with different concentration rosiglitazone (20, 30, 50) μmol/L for 12 h; the groups treated with 30 μmol/L rosiglitazone for (6, 12, 24) h. Morphology changes of the aortic tissues were observed by hematoxylin and eosin stain. The VSMC growth was detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) colorimetric assay. Angiotensin II and expression of angiotensin receptors were determined by radioimmunoassay, reverse transcription polymerase chain reaction (RT-PCR), western blot, and immunohistochemistry. Results After 6 months, lipid deposition, VSMC proliferation and migration toward intima were observed in aortic tissues in the rats on a cholesterol-rich diet plus methylthiouracil, while these pathological changes induced by the cholesterol-rich diet were significantly suppressed by rosiglitazone. In addition, VSMC proliferation induced by ANG II was markedly inhibited by rosiglitazone. Rosiglitazone markedly down-regulated expression of angiotensin type 1 receptor (AT1R) and up-regulated expression of angiotensin type 2 receptor (AT2R) in the aortic tissues and ANG II-treated VSMCs. Conclusions The present study demonstrated that PPARγ agonist rosiglitazone suppressed ANG II-induced VSMC proliferation in vitro and early atherosclerotic formation evoked by cholesterol-rich diet in vivo. These vasculoprotective effects of rosiglitazone were mediated at least partially by reduction in local tissue ANG II concentration, down-regulation of AT1R expression and up-regulation of AT2R expression both at the mRNA and protein levels.