Platform competition with partial multihoming under differentiation: a note

A model of a two-sided market with two horizontally differentiated platforms and multihoming on one side is developed. In contrast to recent contributions, it is shown that platforms do not necessarily generate all revenues on the multihoming side by charging a higher price. Also, whether platforms' pricing structures favor exclusivity over multihoming is ambiguous.multihoming

Special stock market segments for small company shares in Europe - What went wrong?

Special stock market segments for small company shares were established by all major European stock exchanges during the 1980's. After showing a remarkable success during the first years of their existence - both in the primary as well as in the secondary market - these segments today suffer from increasing illiquidity. The stock exchange authorities in London and in Amsterdam have therefore decided to close down their stock markets for smaller companies. This paper takes a closer look at the current situation of these stock market segments throughout Europe and discusses the causes for their decline. --

Cellular and Secretory Proteins of the Salivary Glands of \u3cem\u3eSciara coprophila\u3c/em\u3e During the Larval-pupal Transformation

The cellular and secretory proteins of the salivary gland of Sciara coprophila during the stages of the larval-pupal transformation were examined by electrophoresis in 0.6 mm sheets of polyacrylamide gel with both SDS-continuous and discontinuous buffer systems. After SDS-electrophoresis, all electrophoretograms of both reduced and nonreduced proteins from single glands stained with Coomassie brilliant blue revealed a pattern containing the same 25 bands during the stages of the larval-pupal transformation. With the staining procedures used in this study, qualitative increases and decreases were detected in existing proteins and enzymes. There was no evidence, however, for the appearance of new protein species that could be correlated with the onset of either pupation or gland histolysis. Electrophoretograms of reduced samples of anterior versus posterior gland parts indicated that no protein in the basic pattern of 25 bands was unique to either the anterior or posterior gland part. Electrophoretograms of reduced samples of secretion collected from either actively feeding or cocoon -building animals showed an electrophoretic pattern containing up to six of the 25 protein fractions detected in salivary gland samples, with varied amounts of these same six proteins in electrophoretograms of secretion samples from a given stage. Zymograms of non-specific esterases in salivary gland samples revealed a progressive increase in the amount of esterase reaction produce in one major band and some decrease in the second major band during later stages of the larval-pupal transformation

What is the functional role of adult neurogenesis in the hippocampus?

The dentate gyrus is part of the hippocampal memory system and special in that it generates new neurons throughout life. Here we discuss the question of what the functional role of these new neurons might be. Our hypothesis is that they help the dentate gyrus to avoid the problem of catastrophic interference when adapting to new environments. We assume that old neurons are rather stable and preserve an optimal encoding learned for known environments while new neurons are plastic to adapt to those features that are qualitatively new in a new environment. A simple network simulation demonstrates that adding new plastic neurons is indeed a successful strategy for adaptation without catastrophic interference