1,344 research outputs found

    Microwave radiometric studies and ground truth measurements of the NASA/USGS Southern California test site

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    The field measurement program conducted at the NASA/USGS Southern California Test Site is discussed. Ground truth data and multifrequency microwave brightness data were acquired by a mobile field laboratory operating in conjunction with airborne instruments. The ground based investigations were performed at a number of locales representing a variety of terrains including open desert, cultivated fields, barren fields, portions of the San Andreas Fault Zone, and the Salton Sea. The measurements acquired ground truth data and microwave brightness data at wavelengths of 0.8 cm, 2.2 cm, and 21 cm

    Factors Influencing Internet Gamblers’ Use of Offshore Online Gambling Sites: Policy Implications

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    Gambling is a heavily regulated activity, but policies are difficult to enforce in the online context. While governments may attempt to restrict access to licensed providers only, consumers can access offshore sites, creating a potential risk of harm and reducing taxation. This article examines how consumers select Internet gambling sites, and the characteristics of those who use offshore as opposed to domestic sites. Past‐month Australian Internet‐gamblers (N = 1,001, 57.2 percent male) completed an online survey. Participants responded to questions about their online gambling, including use of offshore sites, reasons for site selection, awareness of regulations, preferences for regulated sites, and gambling‐related problems. Offshore gamblers (52.7 percent) were a distinct demographic cohort, and were more highly involved in online gambling. Lack of awareness of gambling regulation did not sufficiently explain use of offshore gambling sites; rather, both groups had a relatively low concern for where a site was regulated, choosing sites instead based on ease of use, and cues that they were designed for gamblers in the advertised jurisdiction. Use of offshore gambling sites may be discouraged by focusing on the benefits of domestic sites and ensuring that these can provide a good consumer experience

    Measurements of Isoprene-Derived Organosulfates in Ambient Aerosols by Aerosol Time-of-Flight Mass Spectrometry—Part 2: Temporal Variability and Formation Mechanisms

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    Organosulfate species have recently gained attention for their potentially significant contribution to secondary organic aerosol (SOA); however, their temporal behavior in the ambient atmosphere has not been probed in detail. In this work, organosulfates derived from isoprene were observed in single particle mass spectra in Atlanta, GA during the 2002 Aerosol Nucleation and Characterization Experiment (ANARChE) and the 2008 August Mini-Intensive Gas and Aerosol Study (AMIGAS). Real-time measurements revealed that the highest organosulfate concentrations occurred at night under a stable boundary layer, suggesting gas-to-particle partitioning and subsequent aqueous-phase processing of the organic precursors played key roles in their formation. Further analysis of the diurnal profile suggests possible contributions from multiple production mechanisms, including acid-catalysis and radical-initiation. This work highlights the potential for additional SOA formation pathways in biogenically influenced urban regions to enhance the organic aerosol burden

    Measurements of Isoprene-Derived Organosulfates in Ambient Aerosols by Aerosol Time-of-Flight Mass Spectrometry - Part 1: Single Particle Atmospheric Observations in Atlanta

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    Organosulfate species have recently been identified as a potentially significant class of secondary organic aerosol (SOA) species, yet little is known about their behavior in the atmosphere. In this work, organosulfates were observed in individual ambient aerosols using single particle mass spectrometry in Atlanta, GA during the 2002 Aerosol Nucleation and Characterization Experiment (ANARChE) and the 2008 August Mini-Intensive Gas and Aerosol Study (AMIGAS). Organosulfates derived from biogenically produced isoprene were detected as deprotonated molecular ions in negative-ion spectra measured by aerosol time-of-flight mass spectrometry; comparison to high-resolution mass spectrometry data obtained from filter samples corroborated the peak assignments. The size-resolved chemical composition measurements revealed that organosulfate species were mostly detected in submicrometer aerosols and across a range of aerosols from different sources, consistent with secondary reaction products. Detection of organosulfates in a large fraction of negative-ion ambient spectra − ca. 90−95% during ANARChE and ~65% of submicrometer particles in AMIGAS − highlights the ubiquity of organosulfate species in the ambient aerosols of biogenically influenced urban environments

    Extensive spontaneous plasticity of corticospinal projections after primate spinal cord injury.

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    Although axonal regeneration after CNS injury is limited, partial injury is frequently accompanied by extensive functional recovery. To investigate mechanisms underlying spontaneous recovery after incomplete spinal cord injury, we administered C7 spinal cord hemisections to adult rhesus monkeys and analyzed behavioral, electrophysiological and anatomical adaptations. We found marked spontaneous plasticity of corticospinal projections, with reconstitution of fully 60% of pre-lesion axon density arising from sprouting of spinal cord midline-crossing axons. This extensive anatomical recovery was associated with improvement in coordinated muscle recruitment, hand function and locomotion. These findings identify what may be the most extensive natural recovery of mammalian axonal projections after nervous system injury observed to date, highlighting an important role for primate models in translational disease research

    Geographies of science and technology 1:Boundaries and crossings

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    In a world of accelerating environmental crises, global pandemics and seemingly unstoppable datafication of anything that moves, thinks or feels, the politics of science and technology are pervasive. In this first of three progress reports on the geographies of science and technology, I home in on some definitional questions which an account of anything like a new or emerging subfield must necessarily concern itself. I examine how geographers have addressed the spatial effects of the making and unmaking of boundaries between science, technology and their various outsides. While work on historical and contemporary geographies of technoscience has often pulled in slightly different directions, I identify some promising convergences around questions of political economy and on the topic of scale as an emergent property of technoscientific practices. New attention is also falling on the spatial practices through which technoscience gets plugged into wider worlds, such as politics and policymaking, while geographers have also been busy disrupting, in a more experimental mode, conventional boundaries and hierarchies of technoscientific practice. Finally, the report examines recent and welcome efforts to convene new conversations around the geography of technology but cautions against the potential seduction of the new, the innovative and the ‘disruptive’. Important recent work in cultural geography has purposively unsettled assumed hierarchies of ‘high’ and ‘low’ tech, new and old, and suggests that any nascent subfield of ‘geography of technology’ needs to reflexively attend to how boundaries get drawn around ‘technology’, and with what effects
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