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The conventional method of human oocyte maturation in vitro in the presence of gonadotrophins continues to be a relatively low-success procedure in the assisted conception programme owing to suboptimal maturation conditions in the absence of an ovarian 'niche' and poor understanding of this procedure at the molecular level in oocytes. In this study, the gene expression profiles of human oocytes were analysed according to their manner of maturation: in vivo (in the ovaries) or in vitro (matured either by the conventional method or by a new approach - co-cultured with cumulus cells of mature oocytes from the same patient). Our results show that the in-vitro maturation procedure strongly affects the gene expression profile of human oocytes, including several genes involved in transcriptional regulation, embryogenesis, epigenetics, development, and the cell cycle. The in-vitro maturation of oocytes co-cultured with cumulus cells from mature oocytes provides an ovarian 'niche' to some degree, which improves oocyte maturation rates and their gene expression profile to the extent that they are more comparable to oocytes that naturally mature in the ovarian follicle.

Oxidation catalysts in emissions control systems generally contain Pd/Pt and require exhaust temperatures above 200 °C to operate, but under low-temperature conditions, oxidation of CO and hydrocarbons are challenging. As engine efficiency improves and exhaust temperature decreases, there is an increasing demand for high emissions control performance at low temperatures. Therefore, it becomes imperative to design new catalysts that are active at low operating temperatures. Au–CuOx catalysts, made through the oxidation of AuCu alloy nanoparticles, have been found to be highly active for the oxidation of CO at low reaction temperatures. The catalytic activity for the conversion of CO using Au–CuOx/SiO2 was evaluated under simulated lean exhaust conditions (CO, C3H6, NO, H2O, O2 and Ar). It was found that the oxidation of CO over the Au–CuOx/SiO2 catalyst was inhibited when C3H6 or NO was introduced into the reaction stream. Interestingly, a physical mixture of Au–CuOx/SiO2 and Pt/Al2O3 worked in synergy to enhance the oxidation of NO to NO2 with 90% conversion near 300 °C in the presence of CO. This reactivity is on par with Pt/Al2O3 NO oxidation activity in the absence of CO. The Au–CuOx/SiO2 catalysts were also found to be thermally stable after being aged up to 700 °C for 10 h. The resistance to particle sintering can be attributed to the CuOx “anchoring” the Au particles to the silica support.

The effect of adding Pt to a Pd/SiO 2 catalyst for the direct formation of H 2 O 2 in ethanol that contains H 2 SO 4 and halide ions (Cl − or Br − ) has been investigated. The addition of only 5 atom% Pt to a catalyst that contained 0.5 wt.% Pd resulted in a 2.5-fold increase in the rate of peroxide formation with only a small decrease in selectivity. The addition of substantially more Pt caused a decrease in the selectivity; whereas, the peroxide formation rate depended on the amount of Pt, as well as the type and amount of the halide. The Pt had no significant effect on the particle size distribution of the supported bimetallic catalysts. The positive role of Pt on the rate of H 2 O 2 formation can be understood in terms of an electronic modification through which Pt partially reverses the negative influence that the halides have on hydrogen activation.