19,574 research outputs found

    Retire Later or Work Harder?

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    We compare two policies of increasing British state pension provision: (a) increase the pensionable age of men and women, (b) maintain the existing retirement age but require older workers to work longer per-period hours. There are reasons for policy makers to give serious consideration to the under-researched alternative (b). First, from wage - hours contract theory we know that there are potential gains to both workers and firms of allowing hours to rise in work experience. Second, there is strong evidence that job satisfaction rises in age. Third, there has in any case been a significant overall increase in the hours supplied by older workers in the last two decades. We review the relevant theory, model the trade-off between later retirement versus increased work intensity, produce relevant background facts, and provide estimates of the policy trade-offs.older workers, statutory retirement age, hours of work

    Unitarisation of EFT Amplitudes for Dark Matter Searches at the LHC

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    We propose a new approach to the LHC dark matter search analysis within the effective field theory (EFT) framework by utilising the K-matrix unitarisation formalism. This approach provides a reasonable estimate of the dark matter production cross section at high energies, and hence allows reliable bounds to be placed on the cut-off scale of relevant operators without running into the problem of perturbative unitarity violation. We exemplify this procedure for the effective operator D5 in monojet dark matter searches in the collinear approximation. We compare our bounds to those obtained using the truncation method and identify a parameter region where the unitarisation prescription leads to more stringent bounds.Comment: 20 pages, 7 figures. References added and minor corrections made to match published versio

    On Space Exploration and Human Error: A Paper on Reliability and Safety

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    NASA space exploration should largely address a problem class in reliability and risk management stemming primarily from human error, system risk and multi-objective trade-off analysis, by conducting research into system complexity, risk characterization and modeling, and system reasoning. In general, in every mission we can distinguish risk in three possible ways: a) known-known, b) known-unknown, and c) unknown-unknown. It is probably almost certain that space exploration will partially experience similar known or unknown risks embedded in the Apollo missions, Shuttle or Station unless something alters how NASA will perceive and manage safety and reliabilit

    Hydrothermal activity lowers trophic diversity in Antarctic sedimented hydrothermal vents

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    Sedimented hydrothermal vents are those in which hydrothermal fluid vents through sediment and are among the least studied deep-sea ecosystems. We present a combination of microbial and biochemical data to assess trophodynamics between and within hydrothermally active and off-vent areas of the Bransfield Strait (1050–1647 m depth). Microbial composition, biomass and fatty acid signatures varied widely between and within vent and non-vent sites and provided evidence of diverse metabolic activity. Several species showed diverse feeding strategies and occupied different trophic positions in vent and non-vent areas and stable isotope values of consumers were generally not consistent with feeding structure morphology. Niche area and the diversity of microbial fatty acids reflected trends in species diversity and was lowest at the most hydrothermally active site. Faunal utilisation of chemosynthetic activity was relatively limited but was detected at both vent and non-vent sites as evidenced by carbon and sulphur isotopic signatures, suggesting that the hydrothermal activity can affect trophodynamics over a much wider area than previously thought

    Cycles of construing in radicalization and deradicalization: a study of Salafist Muslims.

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    © Taylor & Francis Group, LLC.This article explores radicalization and deradicalization by considering the experiences of six young Tunisian people who had become Salafist Muslims. Their responses to narrative interviews and repertory grid technique are considered from a personal construct perspective, revealing processes of construing and reconstruing, as well as relevant aspects of the structure and content of their construct systems. In two cases, their journeys involved not only radicalization but self-deradicalization, and their experiences are drawn on to consider implications for deradicalization.Peer reviewedFinal Accepted Versio
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