This effect

was not modulated by memory load or the frequency of trials in which a target appeared. However, there was no enhancement when the target appeared at the same time as the probe display (Experiment 2a) or during the memory retention interval (Experiment 2b). Together these results suggest that Omipalisib ic50 detecting a target facilitates the encoding of unrelated information into visual short-term memory. (C) 2010 Elsevier Ltd. All rights reserved.”
“Liver cell aggregates may be grown in vitro by co-culturing hepatocytes with stellate cells. This method results in more rapid aggregation than hepatocyte-only culture, and appears to enhance cell viability and the expression of markers of liver-specific functions. We consider the early stages of aggregate formation, and develop a new mathematical model to investigate two alternative hypotheses (based on evidence in the experimental literature) for the role of stellate cells in promoting aggregate formation. Under Hypothesis 1, each population produces www.selleckchem.com/products/i-bet151-gsk1210151a.html a chemical signal which affects the other, and enhanced aggregation is due to chemotaxis. Hypothesis 2 asserts that the interaction between the two cell types is by direct physical contact: the stellates extend long cellular processes which pull the hepatocytes

into the aggregates. Under both hypotheses,

hepatocytes are attracted to a chemical they themselves produce, and the cells can experience repulsive forces due to overcrowding. We formulate non-local (integro-partial differential) equations to describe the TGF-beta inhibitor densities of cells, which are coupled to reaction-diffusion equations for the chemical concentrations. The behaviour of the model under each hypothesis is studied using a combination of linear stability analysis and numerical simulations. Our results show how the initial rate of aggregation depends upon the cell seeding ratio, and how the distribution of cells within aggregates depends on the relative strengths of attraction and repulsion between the cell types. Guided by our results, we suggest experiments which could be performed to distinguish between the two hypotheses. (C) 2010 Elsevier Ltd. All rights reserved.”
“Despite being extensively studied, many important questions regarding visual short-term memory (VSTM) are yet to be fully answered. The present review seeks to explore the extent to which competitive interactions present during perception of stimuli may also operate during stimulus encoding and/or maintenance in VSTM. Additionally, the paper provides an overview of the methods and approaches that have been used to study the properties of VSTM, and a review of research into the limits of VSTM capacity.