Effects of ovary storage time on the quality and meiotic competence of cat oocytes

In this study the growth of Si and Si$_{1-x}$Ge$_{x}$ layers fabricated by LPCVD epitaxy was investigated with regard to the realization of extended CMOS devices. especially the vertical MOSFET and the n-MODFET. Main focus was the production of thin, threading-dislocation-free relaxed buffer layers which can be used as virtual substrates for strained Si layers. The pursued concept consists of a low-temperature Si$_{1-x}$Ge$_{x}$ layer beneath the intrinsic relaxed buffer layer. Optimizing the low-temperature buffer layer the threading dislocation density could be drastically reduced from 1 x 10$^{11}$ to 1 x 10$^{7}$ cm$^{-2}$. The second purpose of this study was the investigation of phosphorous-doped ni-layers for vertical MOSFETs. Using germane and a high-temperature desorption step the ni-doping could be reduced immediately after turning off the phosphine flow resulting in an improved doping profile (1430 to 50 nm/Dec.). Based on optimized layers, vertical n-MOSFETs with a channel length of 100 nm and a gate oxide thickness of 10 nm a transconductance of 200 mS/mm. High-frequency measurements resulted in cut-off frequencies of f$_{T}$ =8 GHz and f$_{max}$ =19 GHz

Maturation and fertilisation of sheep oocytes cultured in serum-free medium containing silk protein sericin

Sericin is a water-soluble component of silk and has been used as a biomaterial due to its antibacterial and ultraviolet radiation-resistant properties. This study was designed to evaluate the effect of sericin supplementation in a maturation medium on the meiotic competence and fertilisability of sheep oocytes. Cumulus-oocyte complexes (COCs) were cultured in TCM199 supplemented with sericin at various concentrations of 0 (control), 0.1, 0.25 and 0.5%, either with or without bovine serum albumin (BSA). When the COCs were matured without BSA, the supplementation of 0.1% sericin significantly increased the rates of maturation to metaphase II and the total fertilisation of oocytes compared with the other concentrations of sericin. When the COCs were matured with BSA, the beneficial effects of 0.1% sericin supplementation on the maturation and fertilisation of oocytes were not observed. Our findings indicate that supplementation with 0.1% sericin during maturation culture may improve the nuclear maturation and fertilisability of sheep oocytes. Moreover, it may be possible to replace BSA with sericin in chemically defined media without the risk of disease transmission