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The article discusses a study which investigated the effect of the Chinese traditional medicine Jiaweisinisan on rat hippocampal neural precursor cells after stress damage. Topics discussed include the treatment of cells with Jiaweisinisan drug-containing serum and the corticosterone antagonist RU38486, the proliferation of neural precursor cells after corticosterone exposure and the increase in neuron-like cell differentiation from neural precursor cells.

new aliphatic polycarbonate, terpolymer of carbon dioxide, propylene oxide, and dl-lactide, was synthesized by using a polymer-supported bimetallic complex as a catalyst. The terpolymer prepared was characterized by FT-IR, H NMR, C NMR, H-H COSY, DSC, and WAXD measurements. The influence of molar ratio on the terpolymerization progress was investigated. The results showed that lactide unit was inserted into the backbone of CO-PO successfully. Because of the existence of the lactide ester unit, the terpolymers had stronger degradability than poly(propylene carbonate). [ABSTRACT FROM AUTHOR]

Background and aim: Polysaccharide from fuzi (FPS), a Chinese herbal medicine extract, has been demonstrated to exert lipid lowering affects. In this study we examined potential mechanisms underlying this affect, specifically alterations in expression of the LDL-receptor (LDL-R), 3-hydroxy-3-methyl glutaryl (HMG)-CoA reductase and cytochrome P450 7a-1 (CYP7a-1), using a rat model of hypercholesterolemia. Methods and results: Male rats were fed either a normal or high cholesterol (HC) diet for two-weeks. Half of the rats on the HC diet were orally gavaged with FPS (224 mg/kg, 448 mg/kg or 896 mg/kg diet) daily. Serum lipid levels were quantified at end of the study period as were liver levels of LDL-R protein and mRNA expression of CYP7α-1 and HMG-CoA. Serum cholesterol and LDL-C concentrations were significantly elevated from control in HC rats, but not in those treated with FPS (P < 0.05). LDL-R expression was significantly decreased in the HC group compared to control (P < 0.05), but significantly increased in the FPS group (P < 0.05). HMG-CoA mRNA levels were significantly increased in the HC group compared both other groups (P < 0.05), while CYP7α-1 expression was significantly higher in the FPS group compared to both other groups (P < 0.05). Conclusion: These findings suggest that the cholesterol lowering effect of FPS in hypercholesteremic rats is caused at least in part by increased hepatic LDL-R and CYP7α-1 expression and decreased HMG-CoA expression. Further study is needed to determine precisely where and how FPS exerts these effects. FPS offers potential as a therapeutic agent for the treatment of hypercholesterolemia. [ABSTRACT FROM AUTHOR]

In this paper, the impact of heavy ion irradiation on the performance of novel REDI LDMOS (RESURF Dielectric Inserted Lateral Double-diffused MOS transistor) power devices is experimentally investigated for the first time. The performance degradation of REDI LDMOS caused by micro-dose effect and displacement damage (DD) is demonstrated, and the impact of ion fluence and device geometry is analysed. Different degradation behavior occur due to the intrinsic random incident of heavy ions. The threshold voltage (Vth) of the device is barely changed after irradiation. The off-state leakage current (Ioff) of the device may increase or decrease after irradiation, which can change by up to 2 orders of magnitude. The breakdown voltage (BV) of REDI LDMOS may decrease by up to 50%. In addition, the on-resistance (Ron) and on-state current (Ion) of the device are changed by up to about 40%. Further, heavy ion fluence has significant effect on device characteristics after irradiation. For low-fluence (5 × 108 ions cm−2), the degradation of BV is the main problem caused by irradiation. And BV, Ron and Ion degradation should be paid attention for devices irradiated by high-fluence (5 × 109 ions cm−2) heavy ion. Besides, the distance between p+ region and the drift region boundary (LD) has negligible effect on the performance degradation of the irradiated device. However, the maximum value and variation of BV degradation of devices irradiated by high-fluence heavy ion increase with the increase of the length of the gate overlap the drift region (Lov). The results are of great significance for the research of the radiation-hardened technology of power devices. [ABSTRACT FROM AUTHOR]

In this paper, performance degradation after heavy-ion irradiation in novel quasi-SOI devices are investigated and compared with bulk Si MOSFETs through experiment and simulation. A quasi-SOI device is characterized with an L-type insulator surrounding the source and drain regions. The I–V characteristic of the quasi-SOI device may degrade after heavy-ion irradiation and the degradation phenomena are demonstrated and statistically analyzed. The results show that compared with bulk Si devices, quasi-SOI devices illustrate a reduced performance degradation induced by heavy-ion irradiation. Therefore, quasi-SOI devices are promising candidates for future space applications. [ABSTRACT FROM AUTHOR]