3,713 research outputs found

    The Goals of Antitrust: Welfare Trumps Choice

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    Marine baseline and monitoring strategies for Carbon Dioxide Capture and Storage (CCS)

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    The QICS controlled release experiment demonstrates that leaks of carbon dioxide (CO2) gas can be detected by monitoring acoustic, geochemical and biological parameters within a given marine system. However the natural complexity and variability of marine system responses to (artificial) leakage strongly suggests that there are no absolute indicators of leakage or impact that can unequivocally and universally be used for all potential future storage sites. We suggest a multivariate, hierarchical approach to monitoring, escalating from anomaly detection to attribution, quantification and then impact assessment, as required. Given the spatial heterogeneity of many marine ecosystems it is essential that environmental monitoring programmes are supported by a temporally (tidal, seasonal and annual) and spatially resolved baseline of data from which changes can be accurately identified. In this paper we outline and discuss the options for monitoring methodologies and identify the components of an appropriate baseline survey

    Applications of the Band-Limited-White Noise Source Model for Predicting Site-Specific Strong Ground Motions

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    Since the Band-Limited-White-Noise (BLWN) source model coupled with random vibration theory (RVT) was first developed in the early 1980\u27s, it has been used successfully to predict strong ground motions at rock sites in different tectonic regimes. The BLWN-RVT methodology is appropriate for an engineering characterization of strong ground motions at a site since the method captures the important features of these motions in terms of peak acceleration and spectral composition and requires a minimum of input parameters. Recently, the capability to estimate strong ground motions at soil sites has been incorporated into the methodology by using RVT and plane-wave propagators in an equivalent-linear formulation. Thus, non-linear soil response that may occur at high strain levels can now be directly estimated and analyzed. Four cases in which the BLWN-RVT methodology has been applied to predict strong ground motions will be discussed: (l) a moment magnitude (M) 7.9 New Madrid earthquake located 10 km beneath a rock site and a deep soil site; (2) a M 6.9 event similar to the 1983 Borah Peak, Idaho earthquake at several rock and thin soil sites at source-to-site distances of 10 to 27 km; (3) a M 8.0 Cascadia subduction zone earthquake at both a deep alluvial and hypothetical hard rock site in Seattle, Washington at a source-to-site distance of 70 km; and (4) a M 7.0 earthquake occurring along the Hayward fault in the eastern San Francisco Bay region at an 18-m-thick soil site, 15 km from the fault. The effects of soil amplification or deamplification (possibly due to either non-linear soil response or soil damping) will be emphasized in these case histories

    A Resolved Ring of Debris Dust around the Solar Analog HD 107146

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    We present resolved images of the dust continuum emission from the debris disk around the young (80-200 Myr) solar-type star HD 107146 with CARMA at Ν = 1.3 mm and the CSO at Ν = 350 Ο. Both images show that the dust emission extends over an approximately 10" diameter region. The high-resolution (3") CARMA image further reveals that the dust is distributed in a partial ring with significant decrease in a flux inward of 97 AU. Two prominent emission peaks appear within the ring separated by ~140° in the position angle. The morphology of the dust emission is suggestive of dust captured into a mean motion resonance, which would imply the presence of a planet at an orbital radius of ~45-75 AU

    The challenges of intersectionality: Researching difference in physical education

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    Researching the intersection of class, race, gender, sexuality and disability raises many issues for educational research. Indeed, Maynard (2002, 33) has recently argued that ‘difference is one of the most significant, yet unresolved, issues for feminist and social thinking at the beginning of the twentieth century’. This paper reviews some of the key imperatives of working with ‘intersectional theory’ and explores the extent to these debates are informing research around difference in education and Physical Education (PE). The first part of the paper highlights some key issues in theorising and researching intersectionality before moving on to consider how difference has been addressed within PE. The paper then considers three ongoing challenges of intersectionality – bodies and embodiment, politics and practice and empirical research. The paper argues for a continued focus on the specific context of PE within education for its contribution to these questions

    Combining comparative proteomics and molecular genetics uncovers regulators of synaptic and axonal stability and degeneration in vivo.

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    Degeneration of synaptic and axonal compartments of neurons is an early event contributing to the pathogenesis of many neurodegenerative diseases, but the underlying molecular mechanisms remain unclear. Here, we demonstrate the effectiveness of a novel "top-down" approach for identifying proteins and functional pathways regulating neurodegeneration in distal compartments of neurons. A series of comparative quantitative proteomic screens on synapse-enriched fractions isolated from the mouse brain following injury identified dynamic perturbations occurring within the proteome during both initiation and onset phases of degeneration. In silico analyses highlighted significant clustering of proteins contributing to functional pathways regulating synaptic transmission and neurite development. Molecular markers of degeneration were conserved in injury and disease, with comparable responses observed in synapse-enriched fractions isolated from mouse models of Huntington's disease (HD) and spinocerebellar ataxia type 5. An initial screen targeting thirteen degeneration-associated proteins using mutant Drosophila lines revealed six potential regulators of synaptic and axonal degeneration in vivo. Mutations in CALB2, ROCK2, DNAJC5/CSP, and HIBCH partially delayed injury-induced neurodegeneration. Conversely, mutations in DNAJC6 and ALDHA1 led to spontaneous degeneration of distal axons and synapses. A more detailed genetic analysis of DNAJC5/CSP mutants confirmed that loss of DNAJC5/CSP was neuroprotective, robustly delaying degeneration in axonal and synaptic compartments. Our study has identified conserved molecular responses occurring within synapse-enriched fractions of the mouse brain during the early stages of neurodegeneration, focused on functional networks modulating synaptic transmission and incorporating molecular chaperones, cytoskeletal modifiers, and calcium-binding proteins. We propose that the proteins and functional pathways identified in the current study represent attractive targets for developing therapeutics aimed at modulating synaptic and axonal stability and neurodegeneration in vivo
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