36 research outputs found

    Decision-making heuristics for managing climate-related risks: introducing equity to the FREE framework

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    Managing climate-related risks is clouded in differing levels of uncertainty that are magnified when trying to understand their potential impacts on socio-ecological systems. The ‘cascade of uncertainty’ is particularly apparent in Africa where socio-ecological data are sparse, and the development and validation of impact models are at varying stages. In this context, using heuristics may serve as an effective way for policy makers to incorporate climate change knowledge into decision-making. Previous scholarship has identified the principles of Flexibility, Robustness and Economic low/no regrets in decision-making under uncertainty. In this chapter, we first make the case for adding Equity to these heuristics, where equity involves ensuring that reducing the climate change risk for one cohort of society does not result in its increase for another. Second, we describe how these principles have been applied under two DFID/NERC funded projects: ForPAc and AMMA-2050 through the use of Participatory Impact Pathways Analysis tools

    Role for Circadian Clock Genes in Seasonal Timing: Testing the Bunning Hypothesis

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    A major question in chronobiology focuses around the “Bünning hypothesis” which implicates the circadian clock in photoperiodic (day-length) measurement and is supported in some systems (e.g. plants) but disputed in others. Here, we used the seasonally-regulated thermotolerance of Drosophila melanogaster to test the role of various clock genes in day-length measurement. In Drosophila, freezing temperatures induce reversible chill coma, a narcosis-like state. We have corroborated previous observations that wild-type flies developing under short photoperiods (winter-like) exhibit significantly shorter chill-coma recovery times (CCRt) than flies that were raised under long (summer-like) photoperiods. Here, we show that arrhythmic mutant strains, per01, tim01 and ClkJrk, as well as variants that speed up or slow down the circadian period, disrupt the photoperiodic component of CCRt. Our results support an underlying circadian function mediating seasonal daylength measurement and indicate that clock genes are tightly involved in photo- and thermo-periodic measurements

    The distinct roles of spirituality and religiosity in physical and mental health after collective trauma: a national longitudinal study of responses to the 9/11 attacks

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    Researchers have identified health implications of religiosity and spirituality but have rarely addressed differences between these dimensions. The associations of religiosity and spirituality with physical and mental health were examined in a national sample (N = 890) after the September 11, 2001 terrorist attacks (9/11). Health information was collected before 9/11 and health, religiosity, and spirituality were assessed longitudinally during six waves of data collection over the next 3 years. Religiosity (i.e., participation in religious social structures) predicted higher positive affect (β = .12), fewer cognitive intrusions (β = -.07), and lower odds of new onset mental (incidence rate ratio [IRR] = .88) and musculoskeletal (IRR = .94) ailments. Spirituality (i.e., subjective commitment to spiritual or religious beliefs) predicted higher positive affect (β = .09), lower odds of new onset infectious ailments (IRR = 0.83), more intrusions (β = .10) and a more rapid decline in intrusions over time (β = -.10). Religiosity and spirituality independently predict health after a collective trauma, controlling for pre-event health status; they are not interchangeable indices of religion

    Robustness and sensitivity analyses for stochastic volatility models under uncertain data structure

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    In this paper, we perform robustness and sensitivity analysis of several continuous-time stochastic volatility (SV) models with respect to the process of market calibration. The analyses should validate the hypothesis on importance of the jump part in the underlying model dynamics. Also an impact of the long memory parameter is measured for the approximative fractional SV model (FSV). For the first time, the robustness of calibrated models is measured using bootstrapping methods on market data and Monte Carlo filtering techniques. In contrast to several other sensitivity analysis approaches for SV models, the newly proposed methodology does not require independence of calibrated parameters - an assumption that is typically not satisfied in practice. Empirical study is performed on a data set of Apple Inc. equity options traded in four different days in April and May 2015. In particular, the results for Heston, Bates and approximative FSV models are provided
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