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Purpose: The aim of this study was to explore the alternations regarding the HMGB1 and TLR4/NF-κB signaling pathway in juvenile rats with febrile seizure (FS). Materials and methods: During the animal modeling of the FS, seizures were triggered every four days by hot water (45 °C), and repeated ten times. After forty days' modeling, rats were divided into different groups according to the degree of seizure (FS (0) - FS (V)). Reverse transcription-polymerase chain reaction (RT-PCR) was used to evaluate the mRNA expressions of the HMGB1, TLR4 and NF-κB in the hippocampus, while Western-blot (WB) and immunofluorescence (IF) were employed to assess protein expressions. The enzyme-linked immunosorbent assay (ELISA) was used for analyzing the protein expressions in peripheral blood. Results: The mRNA levels of the HMGB1, TLR4 and NF-κB in the hippocampus of both FS (V) and FS (IV) groups were significantly higher than WT, while there was no difference between FS (III) and WT. Concerning protein expressions, increased levels of the HMGB1, TLR4, and NF-κB in FS (V) were observed with a good consistency between the WB and IF, while no significant upregulation was shown in FS (IV). The ELISA results showed that the significance of the augmented proteins between the FS (V) and WT were smaller in the serum than the hippocampus. Conclusions: Our study shows seizure degree-related upregulations of HMGB1 and TLR4/NF-κB signaling pathway both in hippocampus and serum of juvenile rats with FS, suggesting the involvement of TLR/NF-κB pathway in inflammation promoted by HMGB1 during FS. [ABSTRACT FROM AUTHOR]

Abstract: Semi-Insulating Gallium Arsenide (SI-GaAs) was implanted with 1.5MeV He+ ions and THz photoconductive antenna (PCA) was prepared on the implanted SI-GaAs surface. The antenna was applied as the THz wave emission source of a terahertz time domain spectroscopy (THz-TDS) and the THz wave emission ability was studied as a function of the implantation dose. It is found that the THz signal intensity increases with increase of implantation dose, and after reaching to a peak value the THz signal intensity decreases with further implantation. The best THz emission ability was achieved at a dose value between 1×1015 and 1×1016 ions/cm2. It is believed that the implantation induced defects in the 1μm-thick surface area are responsible for the enhanced THz emission ability. The work proved that better THz photoconductive antenna than that made by low-temperature-grown GaAs (LT-GaAs) can be produced through He-ion implantation at proper dose. [Copyright &y& Elsevier]

Multilayer ferroelectric and ferromagnetic thin films were fabricated with the following composition and structure: La[sub 0.67]Sr[sub 0.33]MnO[sub x]/(Pb, La)(Ca, Ti)O[sub 3 ](LSMO/PLCT) and (Pb, La)(Ca, Ti)O[sub 3]/La[sub 0.67]Sr[sub 0.33]MnO[sub x] (PLCT/LSMO), with an intention of creating a device of new concept. The films were fabricated using metalorganic deposition. The LSMO/PLCT structured films exhibit the ferroelectric properties while the PLCT/LSMO structured films exhibit the ferromagnetic properties. Compared with the PLCT/Pt structure, the capacitance-frequency and tan δ-frequency properties of the LSMO/PLCT structure are degraded. The magnetoresistance of the PLCT/LSMO structure was measured and the results show that the metal-insulator transition temperature is lower than that of the LSMO/SiO[sub 2]/Si structure. Furthermore, the magnetoresistance at 77 K and at the transition temperature for the PLCT/LSMO structure is higher than that of the LSMO/SiO[sub 2]/Si structure. These effects can be explained by the piezoelectricity of the PLCT film deposited on the LSMO layer. In addition, these effects demonstrate that the ferromagnetic properties can be controlled by the ferroelectric properties of the multilayer films. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

In order to fabricate good quality ferroelectric thin films, PbZrxTi(1–x)O3 (PZT) and SrBi2Ta2O9 (SBT) films were fabricated on SiO2/Si(100) substrates and on Pt/Ti/ SiO2/Si(100) substrates by pulsed laser excimer deposition (PLD). X-ray diffraction, Rutherford backscattering analysis, and atomic force microscopy were used to characterize the structural properties of the samples, which were post-annealed at different temperatures. The results showed that the PZT and SBT films fabricated on Pt/Ti/SiO2/Si(100) substrates and annealed at 700 °C exhibited optimum properties. [Copyright &y& Elsevier]

In the present study, CVD-SiC samples were implanted with 50 keV Mg ions and co-implanted with 30 keV He ions and 50 keV Mg ions at room temperature, and then annealed at 1573 K for 20 h. The recrystallization and Mg diffusion behavior after annealing were characterized and analyzed. ToF-SIMS profiles indicated that Mg diffused faster in the Mg only implanted sample than in the He and Mg co-implanted sample. TEM results showed that He atoms diffused toward the surface regions with high damage to form He bubbles, which aided the recrystallization of the amorphous layer. Calculations by Mean Square Displacement (MSD) method based on MD simulation prove that the diffusion coefficient of Mg in the amorphous SiC is much higher than that in the crystal SiC. These results indicated that the accelerated recrystallization by He bubbles and themselves were responsible for inhibiting the diffusion of Mg in SiC. [ABSTRACT FROM AUTHOR]