Influence of Olfactory Epithelium on Mitral/Tufted Cell Dendritic Outgrowth

Stereotypical connections between olfactory sensory neuron axons and mitral cell dendrites in the olfactory bulb establish the first synaptic relay for olfactory perception. While mechanisms of olfactory sensory axon targeting are reported, molecular regulation of mitral cell dendritic growth and refinement are unclear. During embryonic development, mitral cell dendritic distribution overlaps with olfactory sensory axon terminals in the olfactory bulb. In this study, we investigate whether olfactory sensory neurons in the olfactory epithelium influence mitral cell dendritic outgrowth in vitro. We report a soluble trophic activity in the olfactory epithelium conditioned medium which promotes mitral/tufted cell neurite outgrowth. While the trophic activity is present in both embryonic and postnatal olfactory epithelia, only embryonic but not postnatal mitral/tufted cells respond to this activity. We show that BMP2, 5 and 7 promote mitral/tufted cells neurite outgrowth. However, the BMP antagonist, Noggin, fails to neutralize the olfactory epithelium derived neurite growth promoting activity. We provide evidence that olfactory epithelium derived activity is a protein factor with molecular weight between 50–100 kD. We also observed that Follistatin can effectively neutralize the olfactory epithelium derived activity, suggesting that TGF-beta family proteins are involved to promote mitral/tufted dendritic elaboration

Understanding the growth in outdoor recreation participation: an opportunity for sport development in the United Kingdom

© 2018, © 2019 Informa UK Limited, trading as Taylor & Francis Group. This paper examines the growth in importance and scale of the outdoor recreation sector in the United Kingdom. It establishes a five-component model to help understand the growth in this sub-sector of the wider sport and physical activity industry. The paper is based on a narrative literature review of the importance of outdoor recreation and also sets the position of the sector in terms of sport policy in the UK. From determining the factors that are underpinning the growing importance of the sector the article goes on to establish implications for policy and practice in sport policy and development in the UK and beyond. It seeks to establish lesson learning between industry and academia that has underpinned the evolution of outdoor recreation policy development in recent years. Furthermore, it establishes future research agendas and directions for those working in outdoor recreation and physical activity spaces and places

Argonne National Laboratory Reports

A data-collection and advisory team was formed to investigate observations of power reactivity decrement (PRD) and reactivity loss rate (RLR) obtained during EBR-II reactor run 74, because both the PRD and RLR were judged to be high during that run. This report describes the efforts to develop a realistic model explaining the reactivity observations for run 74 and presents recommendations for additional diagnostic information in the event of a recurrence of off-normal behavior of reactivity