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AbstractTo study the changes of motor and cognitive function of pituitary tumor rats after the operation. Methods: The experiment was divided into three groups: control group, model group and operation group (30 animals for each group). Female Fischer344 rats were selected. Model group rats were subcutaneously embedded with 10 mg estrogen sustained-release pump to induce a pituitary tumor model, and control group rats were subcutaneously embedded with a normal saline sustained-release pump as control. The operation group was successfully treated by microsurgery after the model was established. The quantitative expressions of PTTG, FGF-2 and VEGF were detected by Western blot. Morris test was used to detect the spatial learning and memory ability of rats. Western blot results showed that compared with the model group, the expression of the operation group was decreased, but still higher than that of the control group (p

Being an important semiconductor material for high power applications, silicon carbide (SiC) faces the problems while used as a gate oxygen layer in traditional Si MOS devices. In view of this, an innovative approach was adopted in the present work to replace the conventional SiO _2 with a high-k material (ZrO _2 ) as the gate oxygen layer to investigate its effect on the electrical characteristics of the devices. In particular ZrO _2 films were deposited on Si and SiC substrates by atomic layer deposition (ALD), and Al was used as the electrode. The atomic force microscopy (AFM) microregion scan revealed a highly flat surface with R _q < 1 nm after the ALD growth of ZrO _2 layer. The sample surface analysis via x-ray photoelectron spectroscopy (XPS) suggested the presence of a small amount of ZrO _x components. According to the electron energy loss spectrum (EELS), the band gap width (E _g ) of this ALD ZrO _2 dielectric was 5.45 eV, which met the requirements for high-quality 4H-SiC-related MOS devices. The electrical properties of the samples were then studied, and the maximum breakdown voltage of the Al/ZrO _2 /SiC/Al MOS structure was obtained to be 23 V, i.e., nearly twice that of the Si substrate. As for the oxide layer, the interface defect density (D _it ) near the conduction band of the Al/ZrO _2 /SiC/Al MOS structure was only 10 ^12 eV ^−1 cm ^−2 orders of magnitude. The N _eff value (the movable charge) of the structure was also controlled at 10 ^12 cm ^−2 . Therefore, the overall performance of the ZrO _2 /SiC structure in terms of electrical properties exceeded that of the ZrO _2 /Si structure and previously reported counterparts. In this respect, the ZrO _2 /SiC MOS capacitor structure has great research potential.

Here, we demonstrate that the first example of harmaline scaffolds serving as acceptor/acceptor-based N-C-C synthons triggered the ring opening and skeletal reconstruction of 3-vinyl benzofuranones for the construction of a library of skeletally diverse polycyclic harmaline scaffolds. These products were smoothly afforded in up to 77% yield, 420: 1 dr under catalyst-free conditions, and expanded the chemical space of biologically significant harmaline derivative species. All synthetic compounds showed cytotoxic activity against tumor cells, especially compound 3at, which exhibited selective cytotoxicity against A549 cells and lower cytotoxicity against normal cells MRC-5 and HK-2. In further mechanism research, 3at inhibited A549 cell proliferation through the G1 phase arrest, induced A549 cell apoptosis through internal and external apoptosis pathways, and suppressed the migration and invasion abilities of A549 cells. These data indicated that compound 3at is the most effective compound in the series and can serve as a promising precursor for drug development. [ABSTRACT FROM AUTHOR]