A new analogue circuit design methodology using independently optimised self-cascode (SC) structures is proposed. Based on the concept of the dual-workfunction-gate structures, which are equivalent to SC structures, transconductance and output resistance optimised SC MOSFETs were used in the differential input and output stages, respectively. An operational amplifier (opamp) with the proposed design methodology using standard 0.18 µm CMOS technology was designed to provide better performance. The measured DC gain of the fabricated opamp with independently-optimised SC MOSFETs was approximately 12 dB higher than that of the conventional opamp.

In transgenic pig production for generating animal models of human diseases, apoptosis of early implantation embryo disturbs the transgenic pig production. In general, epithelial-mesenchymal transition (EMT) is considered important in embryo development and apoptosis. In addition, it was reported that 17β-oestradiol (E2), among hormones that participate in early implantation of embryo, could induce EMT and neural differentiation in mouse embryonic stem cells. Therefore, in this study, we examined the effects of the steroid hormone, E2, in the changes of EMT and apoptotic markers in porcine embryonic stem cells (pESC) and porcine induced pluripotent stem cells (piPSC). During the study, we cultured pESC and piPSC in pESC media containing basic fibroblast growth factor (b-FGF) and leukemia inhibitory factor (LIF) and performed RT-PCR and an alkaline phophatase (AP) test to measure pluripotent and undifferentiation markers of these porcine stem cells. The RT-PCR results showed that OCT4, NANOG, and SOX2 were expressed in these pESC and piPSC, indicating their pluripotency as stem cells. Also, these porcine stem cells showed positive AP activity, demonstrating undifferentiation. Additionally, we treated pESC and piPSC with E2 to examine effects of steroid hormone on the changes of EMT and apoptotic markers (i.e. bcl-2, bax, E-cad, and vimentin). The E2 treatment increased the expression of vimentin and bcl-2, while decreased the expression of E-cadherin and bax. By using immunocytochemistry (ICC), we examined the protein expression of EMT markers, which are vimentin and E-cadherin at the translational level, and found that expression of vimentin protein was increased while E-cadherin protein level was reduced at periphery of the colonies in pESC and piPSC. In conclusion, these results indicate that E2 can promote EMT process and reverse apoptosis in these pESC and iPSC. In a future study, we will further examine the effects of progesterone on the expressions of EMT and apoptotic markers in pESC and piPSC. Consequently, this study will contribute to elucidate the underlying mechanisms of EMT and apoptosis controlled by steroid hormones in porcine stem cells.

A high-voltage extended drain MOS (EDMOS) transistor with a dual work function gate (DWFG) is discussed. This device enhances device performance by modifying the electric field in the channel. For DWFG EDMOS device fabrication, the polycrystalline silicon gates on the source and drain sides are doped by p + and n + ion implantation, respectively. Experimental results from the fabricated DWFG EDMOS devices show improved transconductance (g m), drain conductance (g ds) and specific on-resistance (R ON) characteristics without breakdown voltage reduction.

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