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In this work, (1− x)Bi 0 · 5 (Na 0 · 8 K 0.2) 0.5 TiO 3 - x SrTiO 3 ceramics were synthesized by the solid-phase method. The SrTiO 3 dopants cause a phase transition from of rhombohedral to tetragonal resulting in an enhanced strain of 0.49 % and normalized strain d 33 * of 817 p.m./V under 60 kV/cm at a doping amount of 0.04. The microstructure of BNKT-0.04ST, including cation displacements δ Ti-Bi/Na and the tilt of oxygen octahedron are researched by aberration corrected scanning transmission electron microscope (AC-STEM). The fast Fourier transform (FFT) of the annular dark field (ADF) STEM pattern along [110] axis reveals the 1/2 (ooo) superlattice reflection spots due to anti-phase a − a − a − the tilt of oxygen octahedron. The cation displacement vector maps based on the ADF STEM and the enhanced annular bright fielde (eABF) STEM images along the [100] axis show the rhombohedral and tetragonal phase nanodomains, and the displacement decreases gradually from the inside of the nanodomains towards the domain walls. The tilt of oxygen octahedron has the same variation tendency indicating the regional coherence. Due to the flexible nanodomains based on the cooperative effect of the tilt of oxygen octahedron and cation displacement, which is thought to be the origin of the relaxor characteristic and strain. [ABSTRACT FROM AUTHOR]

Ginsenoside Rg1 (GS Rg1) is a glycosylated triterpenoid saponin extracted from Panax ginseng. We aim to investigate the impact of GS Rg1 on protein aggregation and inflammatory response in a cerebral ischemia/reperfusion (I/R) injury model. Rats were administered different doses of GS Rg1 (10, 20, or 40 mg/kg/day) or nimodipine (1 mg/kg/day) for 5 consecutive days. Cerebral I/R injury was induced by middle cerebral artery occlusion for 2 h followed by a 22 h reperfusion period. Next, we examined the differences in infarct volume and neurological deficit via TTC staining and Longa′s scoring, respectively. Furthermore, the differences in protein aggregates, proteasome, IκBα and NF-κB in the cerebral cortices were investigated through western blotting. The distribution of ubiquitin, proteasome and NF-κB in the neocortex were examined through immunohistochemistry. Pro-inflammatory cytokines were measured using ELISA and proteasome activity was determined by fluorometric peptidaseassay. Treatment with GS Rg1 40 mg/kg resulted in a significantly lower infarct volume and improved the neurological deficit score as well as the histological appearance compared to the control I/R group (P < 0.05). GS Rg1 treatment resulted in significantly lower proinflammatory cytokine expressions and suppression of the nuclear translocation of NF-κB as well as the phosphorylation of IκBα (P < 0.01). Finally, GS Rg1 treatment decreased the proteasomal activity and protein aggregate accumulation in brain tissues (P < 0.01). Our results confirm the neuroprotective function of GS Rg1 at 40 mg/kg. This effect may be attributed to a decrease in ubiquitinated aggregates and a suppression of the inflammatory response after I/R insult. [ABSTRACT FROM AUTHOR]

High throughput and a long life-time of the devices are two crucial challenges in planar chip technology for electrophysiological measurements of ionic current recording through ion channel proteins. In this paper, we present a wafer-scale process for the generation of novel arrays of microelectrochemical cells for long-term and high-resolution current recording. At the bottom of each of the cells, which have typically diameters of around 60 μm and volumes of around 30 pL, a nanocrystalline silver/silver chloride secondary electrode is generated for ionic current recording. The top of the cell is closed by a lid containing a small (6–16 μm) opening which connects liquid in the chamber to a contacting liquid on the outside. The processes necessary for manufacturing such a chip through photolithography and wafer-scale bonding have been developed, the resulting structures were characterized and the procedures were optimized. Combining a large surface area of the electrode with a – in relation to the cell size – relatively large amount of silver/silver chloride allows for the recording of DC ionic currents for prolonged periods of time. First measurements were performed where the electrochemical cells were closed by model membranes containing single ion channel proteins. The currents generated by ions passing through these ion channels are reported. These measurements demonstrate the usefulness of the microelectrochemical cell array for long time ionic current recordings at – for these type of measurements – relatively high current levels. [ABSTRACT FROM AUTHOR]

The cation displacement closely related to the local symmetry and corner-connected oxygen octahedral rotation are the structural origin of macroscopic properties in ABO 3 perovskite oxides. This work describes in detail the relationship between microstructure and macroscopic properties in 0.78BT-0.12CT-0.1BZS ceramic, which achieves the enhanced strain of 0.19 % with a hysteresis of 6.56 %. The atomic level structure is revealed by aberration corrected scanning transmission electron microscope (AC-STEM). The AC-STEM HAADF images reveal the coexisting of polar nanoregions with O and T symmetries. Such a microstructure has a lower energy barrier, facilitating dynamic polarization rotation flexibly under external stimuli. The AC-STEM ABF image reveals the existence of the BO 6 octahedral rotation, with rotation patterns of the a 0 b 0 c 0 and a - b + c - , and rotation angles are quantitatively measured. The BO 6 octahedral rotation and cation displacement are found to be consistent, the greater octahedral rotation with greater cation displacements. These results have important implications for understanding the structural origin of the excellent properties in ferroelectrics. • (0.9- x)BT- x CT-0.1BZS ferroelectric ceramics were synthesized by conventional solid-state reaction method. • Enhanced strain of 0.19 % with a low hysteresis of 6.56 % was obtained with x = 0.12. • The PNRs with O and T symmetries and BO 6 rotation were revealed by aberration corrected scanning transmission electron microscope. [ABSTRACT FROM AUTHOR]