Firms’ Price Markups and Returns to Scale in Imperfect Markets: Bulgaria and Hungary

Under perfect competition and constant returns to scale, firms producing homogeneous products set their prices at their marginal costs which also equal their average costs. However, the departure from these standard assumptions has important implications with respects to the derived theoretical results and the validity of the related empirical analysis. In particular, monopolistic firms will charge a markup over their marginal costs. We show that firms’ markups tend to be directly associated with the employed production technology, more specifically with their returns to scale. Accordingly, we analyze the implications for the markup ratios from the incidence of non-constant returns to scale. We present quantitative results illustrating the effect of the returns to scale index on the firms’ price markups, as well as the relationship between the two indicators, on the basis of firm-level data for Bulgarian and Hungarian manufacturing firms.markup pricing, market imperfections, return to scale, Bulgaria, Hungary

The Well-of-the-Well system an efficient approach to improve embryo development /

Transfer of human embryos at the blastocyst stage may offer considerable benefits including an increased implantation rate and a decreased risk of multiple pregnancies; however, blastocyst culture requires an efficient and reliable in-vitro embryo culture system. In this study, the effect of the Well-of-the-Well (WOW) system consisting of microwells formed on the bottom of the culture dish was tested in three mammalian species, including humans. The WOW system resulted in significant improvement when comparing the drops for culture of in-vitro-matured and parthenogenetically activated porcine oocytes, and in-vivo-derived mouse zygotes. In human embryos, using a sibling oocyte design, embryos cultured in WOW developed to the blastocyst stage in a significantly higher proportion than did embryos cultured traditionally (55% in WOW and 37% in conventional culture; P < 0.05). In a separate study, also in human, a total of 48 patients with a cumulative 214 unsuccessful previous IVF cycles were selected for the trials. In subsequent intracytoplasmic sperm injection cycles, oocytes/embryos were cultured individually in the WOW system or in microdrops. Transferable quality blastocyst development (48.9% of cultured zygotes) was observed in the WOW system. Ninety-four blastocysts transferred to 45 patients resulted in clinical pregnancy rates of 48.9%, including nine twin pregnancies, seven single pregnancies, five miscarriages and one ectopic pregnancy. The results indicate that the WOW system provides a promising alternative for microdrop culture of mammalian embryos, including human embryos

The Well-of-the-Well system : an efficient approach to improve embryo development

Transfer of human embryos at the blastocyst stage may offer considerable benefits including an increased implantation rate and a decreased risk of multiple pregnancies; however, blastocyst culture requires an efficient and reliable in-vitro embryo culture system. In this study, the effect of the Well-of-the-Well (WOW) system consisting of microwells formed on the bottom of the culture dish was tested in three mammalian species, including humans. The WOW system resulted in significant improvement when comparing the drops for culture of in-vitro-matured and parthenogenetically activated porcine oocytes, and in-vivo-derived mouse zygotes. In human embryos, using a sibling oocyte design, embryos cultured in WOW developed to the blastocyst stage in a significantly higher proportion than did embryos cultured traditionally (55% in WOW and 37% in conventional culture; P < 0.05). In a separate study, also in human, a total of 48 patients with a cumulative 214 unsuccessful previous IVF cycles were selected for the trials. In subsequent intracytoplasmic sperm injection cycles, oocytes/embryos were cultured individually in the WOW system or in microdrops. Transferable quality blastocyst development (48.9% of cultured zygotes) was observed in the WOW system. Ninety-four blastocysts transferred to 45 patients resulted in clinical pregnancy rates of 48.9%, including nine twin pregnancies, seven single pregnancies, five miscarriages and one ectopic pregnancy. The results indicate that the WOW system provides a promising alternative for microdrop culture of mammalian embryos, including human embryos