88 research outputs found

    Interpopulation differences in expression of candidate genes for salinity tolerance in winter migrating anadromous brown trout (Salmo trutta L.)

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Winter migration of immature brown trout (<it>Salmo trutta</it>) into freshwater rivers has been hypothesized to result from physiologically stressful combinations of high salinity and low temperature in the sea.</p> <p>Results</p> <p>We sampled brown trout from two Danish populations entering different saline conditions and quantified expression of the <it>hsp70 </it>and <it>Na/K-ATPases α 1b </it>genes following acclimation to freshwater and full-strength seawater at 2°C and 10°C. An interaction effect of low temperature and high salinity on expression of both <it>hsp70 </it>and <it>Na/K-ATPase α 1b </it>was found in trout from the river entering high saline conditions, while a temperature independent up-regulation of both genes in full-strength seawater was found for trout entering marine conditions with lower salinities.</p> <p>Conclusion</p> <p>Overall our results support the hypothesis that physiologically stressful conditions in the sea drive sea-run brown trout into freshwater rivers in winter. However, our results also demonstrate intra-specific differences in expression of important stress and osmoregulative genes most likely reflecting adaptive differences between trout populations on a regional scale, thus strongly suggesting local adaptations driven by the local marine environment.</p

    The financialization of mass wealth, banking crises and politics over the long run

    Get PDF
    The co-evolution of democratic politics and mass, financialized wealth has destabilized highly integrated financial systems and the socio-political underpinnings of neoliberal policy norms at domestic and global levels. Over the long run, it has increased the political pressure on governments to undertake bailouts during major banking crises and, by raising voters’ attentiveness to wealth losses and distributional inequities, has sharply raised the bar for government performance. The result has been more costly bailouts, greater political instability and the sustained politicization of wealth cleavages in crisis aftermaths. We underline the crucial importance and modernity of this phenomenon by showing how the high concentration of wealth in pre-1914 Britain and America among elites was associated with limited crisis interventions and surprisingly tranquil political aftermaths. By contrast, the 2007–2009 crises in both countries epitomise the political dilemmas facing elected governments in a new world of mass financialized wealth and the impact on political polarization and democratic politics. We show that these dilemmas were embryonic in the interwar period and highlight how the evolutionary forces shaping policy and political outcomes reveal the importance of time, context and the effects of long cycles in the world economy and global politics

    Pre-neuronal morphological processing of object location by individual whiskers

    No full text
    In the vibrissal system, touch information is conveyed by a receptorless whisker hair to follicle mechanoreceptors, which then provide input to the brain. We examined whether any processing, that is, meaningful transformation, occurs in the whisker itself. Using high-speed videography and tracking the movements of whiskers in anesthetized and behaving rats, we found that whisker-related morphological phase planes, based on angular and curvature variables, can represent the coordinates of object position after contact in a reliable manner, consistent with theoretical predictions. By tracking exposed follicles, we found that the follicle-whisker junction is rigid, which enables direct readout of whisker morphological coding by mechanoreceptors. Finally, we found that our behaving rats pushed their whiskers against objects during localization in a way that induced meaningful morphological coding and, in parallel, improved their localization performance, which suggests a role for pre-neuronal morphological computation in active vibrissal touch
    corecore