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Rosiglitazone has been known to attenuate neurodegeneration in Alzheimer's disease (AD), but the underlying mechanisms remain unclear. In this study, Morris water maze test, ELISA and electrophysiological methods were used to examine the role and underling mechanisms of rosiglitazone on Aβ42 oligomer-induced memory impairments. We found that rosiglitazone attenuated Aβ42 oligomer-induced memory impairments in rats in a dose-dependent manner. The levels of inflammatory cytokines interleukin-1 beta (IL-1β) and interferon gamma (IFNγ) were significantly increased 7 days after injection of Aβ42 oligomers into the rat hippocampus. Inhibition of microglia activation prevented Aβ42 oligomer-induced increases in IL-1β and IFNγ levels. Rosiglitazone completely prevented the increase in the levels of IL-1β and IFNγ induced by Aβ42 oligomers. Treatment of hippocampal slices with the inflammatory cytokine IL-1β or IFNγ significantly inhibited the production of long-term potentiation (LTP) in the dentate gyrus. Rosiglitazone prevented the inhibitory effects of inflammatory cytokines on LTP. Thus, inhibition of inflammatory responses may be part of the mechanisms of action of rosiglitazone on preventing memory deficits induced by Aβ42 oligmers. [ABSTRACT FROM AUTHOR]

Abstract: ZnO and In2O3 nanofibers are synthesized via electrospinning methods, and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscope (TEM), infrared (IR) spectroscopy, and X-ray photoelectron spectroscopy (XPS). The nanofibers are deposited on ceramic substrates to form sensing films with various structures (ZnO nanofiber films, ZnO–In2O3 nanofiber films, and ZnO–In2O3–ZnO nanofiber films), and their sensing properties are investigated at different temperatures. Compared with ZnO nanofiber films and ZnO–In2O3–ZnO nanofiber films, the obtained ZnO–In2O3 nanofiber films exhibit improved and excellent sensing properties to ethanol. The highest sensitivity (the ratio of sensor resistance in air to that in target ambience) of 25 is obtained when the ZnO–In2O3 films are exposed to 100ppm ethanol at 210°C, while the corresponding values are only 8 for ZnO nanofiber films at 300°C and 17 for ZnO–In2O3–ZnO nanofiber films at 210°C. Rapid sensing reactions are also obtained as the response and recovery times of ZnO–In2O3 nanofiber films to 100ppm ethanol are only about 2 and 1s, respectively. These high sensing performances are explained by referring the heterocontacts formed by the double-layer structure. [Copyright &y& Elsevier]

Abstract: The solubilities of lomefloxacin in methanol, ethanol, 1-propanol, 2-propanol, acetone, and chloroform have been determined from 293.15 to 323.15K by a static equilibrium method. The experimental data were correlated with the modified Apelblat equation. The positive Δ sol H and Δ sol S for each system revealed that lomefloxacin being dissolved in each solvent was an entropy-driven process. [Copyright &y& Elsevier]

• The mapping between assembly deviation and the geometric accuracy of a linear axis are clarified. • The measurement and geometric accuracy characterization are united in a uniform datum. • The effect of different assembly deviation on geometric accuracy of the single linear axis is quantified. Geometric accuracy is the direct embodiment of the assembly deviation of a precision motion system. This paper proposes a novel methodology for predicting the geometric accuracy induced by assembly deviation of a precision motion system and tracing the sensitivity of the assembly deviation with respect to geometric accuracy terms. The small displacement torsor is first characterized as the periodic function of the assembly deviation and dimension parameters of the components of ball-screw feeding system, the vector constraint relationship of the parallel assembly of the feeding system is established, and a spatial propagate model of the assembly deviation for the feeding system is then constructed. A random balance design and Fourier amplitude sensitivity test method are introduced to trace the effect of each assembly feature on the geometric accuracy. The experiments were performed on a single-axis feeding system to verify the effectiveness of the proposed method. This method has the advantage that the mapping relationship between the assembly deviation and geometric accuracy with respect to the instructed position is quantified, and the assembly and adjustment is pertinent to the traceability analysis. The model has the potential to accurately allocate and maintain the machining centre. [ABSTRACT FROM AUTHOR]

Highly porous silicon carbide ceramic with a woodlike microstructure has been prepared by carbothermal reduction reaction of charcoal/silica composites in static argon atmosphere, which were fabricated by infiltrating silica sol into a porous biocarbon template from tilia amurensis wood using a vacuum/pressure infiltration process. The morphology of resulting porous SiC ceramic, as well as the conversion mechanism of wood to porous SiC ceramic, have been investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) techniques. Experimental results show that the biomorphic cellular morphology of tilia amurensis wood charcoal tissue is remained in the porous SiC ceramic with high precision which consists of β-SiC with traces of α-SiC. The strut thickness of resulting SiC ceramic becomes thinner, even partially disappears with the increase of silica amount contained in the charcoal/silica composites. The morphology of the SiC ceramic reveals that solid–solid, gas–solid and gas–gas reactions occurred during the charcoal-to-ceramic conversion. [Copyright &y& Elsevier]

Abstract: Hot compression tests in the temperature range from 1273 to 1423 K and strain rate range from 0.01 to 10 s–1 were carried out on a Gleeble 1500D thermo-mechanical simulator for as-cast 21Cr economical duplex stainless steel (EDSS). The deformation behavior and microstructural evolution were investigated. It is found that the flow behavior strongly depends on the strain rate and deformation temperature, and the flow stress increases with the increase of strain rate and the decrease of temperature. The softening degree of ferrite becomes larger with decreasing strain rate and increasing deformation temperature, and the austenite is gradually spheroidizing. The flow localization band easily happens at high strain rate and low temperature because of the uneven deformation in the microstructure. Moreover, the constitutive model with the compensation of strain was developed on the basis of hyperbolic sine equation to predict the flow stress of as-cast 21Cr EDSS. The material constant in the model such as α, n, Q and ln A was functioned with the strain by sixth order polynomial. The results show that the developed constitutive model has excellent predictability of flow stress under the experimental deformation conditions for as-cast 21Cr EDSS. [Copyright &y& Elsevier]

Abstract: A high-temperature physical vapor transport (HTPVT) method was used to grow highly dense SiC ceramics free of sintering aids, and the effects of growth time and temperature upon the grain size, growth rate, thickness and orientation of silicon carbide were explored. Silicon carbide ceramics with a thickness of 8mm and a bulk density of 3.208g/cm−3 were obtained after 4h of growth. The silicon carbide texture exhibited a preferred orientation along (000 l) planes. The degree of grain size and orientation of the silicon carbide increased with increased growth time, and the growth rate increased with the growth temperature and temperature gradient. Silicon carbide ceramics exhibited a bending strength of only 290±34MPa, primarily due to the large grain size (average grain size: 2mm), and a Vickers hardness of 29.7±0.6GPa. [Copyright &y& Elsevier]