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(K0.48Na0.52)NbO3-0.03Bi0.5Na0.5ZrO3 (KNNS-0.03BNZ) ceramics were prepared doped with 3 mol% Bi0.5Na0.5ZrO3 (BNZ), and the effect of sintering temperature on dielectric and piezoelectric properties of KNNS-0.03BNZ was also investigated. KNNS-0.03BNZ ceramics at all sintering temperatures exhibit a single perovskite structure, and the change of sintering temperature has no significant effect on the phase composition of KNNS 0.03BNZ ceramics. The Raman shifts of the ν1 and ν5 vibration modes have irregular changes in all sintering temperature ranges, indicating that there are polycrystalline phases coexisting in this region. With the change of sintering temperature, Tc slightly shifts to the high temperature direction, and TR-T slightly shifts to the high temperature direction, dielectric constant εr continuously increases, while dielectric loss tanδ firstly decreasing and then increasing. Thanks to the presence of a small amount of liquid phase in the ceramics sintered at 1160 °C, piezoelectric coefficient d33 reaches 280 pC/N. [ABSTRACT FROM AUTHOR]

Effects of temperature (25, 160 and 200 °C) and time (15 and 30 min) of steam treatment on the mechanical and chemical characteristics of moso bamboo were studied. The modulus of rupture (MOR) and modulus of elasticity (MOE) of the outer culm were at least 2.4 and 2.2 times respectively greater than those of the inner culm. Temperature and time had no effect on bending properties of the outer and inner culms. A significant decrease in MOR occurred after the specimens were subjected to 200 °C. The per cent MOR reduction after 30 min treatment at 200 °C was more than 33 and 29% respectively, as compared with that of 25 and 160 °C, but steam treatment had no effect on MOE. Of the three major chemical constituents of bamboo, alpha-cellulose was very stable to temperature and time, but lignin content increased slightly when temperature was increased to 200 °C. However, the hemicellulose content decreased substantially as temperature increased. The similar decreases for hemicellulose content and MOR of bamboo suggested that hemicellulose loss in thermally- degraded bamboo was correlated with MOR strength loss. At 200 °C, there were significant decreases in MOR, hemicellulose content and pH, and increases in hot water extractives, ethanol-benzene extractives, 1% NaOH extractives and lignin content. [ABSTRACT FROM AUTHOR]

Background and Purpose: Glycyrrhizae radix has been widely used as a cytoprotective, plant-derived medicine. We have identified a flavanoid, liquiritigenin, as an active component in extracts of Glycyrrhizae radix. This research investigated the effects of liquiritigenin on the induction of inducible NOS (iNOS) and proinflammatory cytokines by lipopolysaccharide (LPS) in Raw264.7 cells, and on paw oedema in rats.Experimental Approach: iNOS expression was determined by western blotting, real-time reverse transcription-PCR and reporter gene analyses. Tumour necrosis factor-alpha (TNF-alpha), interleukin (IL)-1beta and IL-6 were assayed by ELISA. Gel shift assay and immunoblotting were used to assess NF-kappaB activation. The effect of liquiritigenin on acute inflammation in vivo was evaluated using carrageenan-induced paw oedema.Key Results: Treatment of Raw264.7 cells with liquiritigenin caused inhibition of LPS-induced NF-kappaB DNA binding activity, due to repression of I-kappaBalpha phosphorylation and degradation. Liquiritigenin treatment prevented LPS from increasing the levels of iNOS protein and mRNA in a concentration-dependent manner. Liquiritigenin also suppressed the production of TNF-alpha, IL-1beta and IL-6 from Raw264.7 cells after LPS. In rats, liquiritigenin treatment inhibited formation of paw oedema induced by carrageenan.Conclusion and Implications: These results demonstrate that liquiritigenin exerts anti-inflammatory effects, which results from the inhibition of NF-kappaB activation in macrophages, thereby decreasing production of iNOS and proinflammatory cytokines. Our findings showing inhibition by liquiritigenin of paw oedema as well as inflammatory gene induction will help to understand the pharmacology and mode of action of liquiritigenin, and of the anti-inflammatory use of Glycyrrhizae radix. [ABSTRACT FROM AUTHOR]