2,497 research outputs found

    Improvement and evaluation of simulated global biogenic soil NO emissions in an AC-GCM

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    Biogenic NO emissions from soils (SNOx) play important direct and indirect roles in tropospheric chemistry. The most widely applied algorithm to calculate SNOx in global models was published 15 years ago by Yienger and Levy (1995), and was based on very few measurements. Since then, numerous new measurements have been published, which we used to build up a compilation of world wide field measurements covering the period from 1978 to 2010. Recently, several satellite-based top-down approaches, which recalculated the different sources of NOx (fossil fuel, biomass burning, soil and lightning), have shown an underestimation of SNOx by the algorithm of Yienger and Levy (1995). Nevertheless, to our knowledge no general improvements of this algorithm, besides suggested scalings of the total source magnitude, have yet been published. Here we present major improvements to the algorithm, which should help to optimize the representation of SNOx in atmospheric-chemistry global climate models, without modifying the underlying principals or mathematical equations. The changes include: (1) using a new landcover map, with twice the number of landcover classes, and using annually varying fertilizer application rates; (2) adopting a fraction of 1.0 % for the applied fertilizer lost as NO, based on our compilation of measurements; (3) using the volumetric soil moisture to distinguish between the wet and dry states; and (4) adjusting the emission factors to reproduce the measured emissions in our compilation (based on either their geometric or arithmetic mean values). These steps lead to increased global annual SNOx, and our total above canopy SNOx source of 8.6 Tg yr−1 (using the geometric mean) ends up being close to one of the satellite-based top-down approaches (8.9 Tg yr−1). The above canopy SNOx source using the arithmetic mean is 27.6 Tg yr−1, which is higher than all previous estimates, but compares better with a regional top-down study in eastern China. This suggests that both top-down and bottom-up approaches will be needed in future attempts to provide a better calculation of SNOx

    Mid-infrared quantum optics in silicon

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    Applied quantum optics stands to revolutionise many aspects of information technology, provided performance can be maintained when scaled up. Silicon quantum photonics satisfies the scaling requirements of miniaturisation and manufacturability, but at 1.55 μ\mum it suffers from unacceptable linear and nonlinear loss. Here we show that, by translating silicon quantum photonics to the mid-infrared, a new quantum optics platform is created which can simultaneously maximise manufacturability and miniaturisation, while minimising loss. We demonstrate the necessary platform components: photon-pair generation, single-photon detection, and high-visibility quantum interference, all at wavelengths beyond 2 μ\mum. Across various regimes, we observe a maximum net coincidence rate of 448 ±\pm 12 Hz, a coincidence-to-accidental ratio of 25.7 ±\pm 1.1, and, a net two photon quantum interference visibility of 0.993 ±\pm 0.017. Mid-infrared silicon quantum photonics will bring new quantum applications within reach.Comment: 8 pages, 4 figures; revised figures, updated discussion in section 3, typos corrected, added referenc

    A review of methods and tools to assess the implementation of government policies to create healthy food environments for preventing obesity and diet-related non-communicable diseases

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    BACKGROUND: Policies to create healthy food environments are recognized as critical components of efforts to prevent obesity and diet-related non-communicable diseases. There has not been a systematic review of existing methods and tools used to assess the implementation of these government policies. The purpose of this study was to review methods and tools used for assessing the implementation of government policies to create healthy food environments. The study conducted a systematic literature search. Multiple databases as well as the grey literature were searched. All study designs and review papers on assessing the implementation of government policies to create healthy food environments were included. A quality assessment of the methods and tools identified from relevant studies was carried out using the following four criteria: comprehensiveness, relevance, generalizability and feasibility. This quality assessment was completed by two independent reviewers. RESULTS: The review identified 52 studies across different policy areas, levels and settings. Self-administered questionnaires and policy checklists were most commonly applied to assess the extent of policy implementation, whereas semi-structured interviews were most commonly used to evaluate the implementation process. Measures varied widely, with the existence of policy implementation the aspect most commonly assessed. The most frequently identified barriers and facilitators for policy implementation were infrastructure support, resources and stakeholder engagement. The assessment of policy implementation on food environments was usually undertaken in combination with other policy areas, particularly nutrition education and physical activity. Three tools/methods were rated \u27high\u27 quality and 13 tools/methods received \u27medium\u27 quality ratings. CONCLUSIONS: Harmonization of the available high-quality methods and tools is needed to ensure that assessment of government policy implementation can be compared across different countries and settings and over time. This will contribute to efforts to increase government accountability for their actions to improve the healthiness of food environments

    Regulation to create environments conducive to physical activity : understanding the barriers and facilitators at the Australian State Government level

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    Introduction Policy and regulatory interventions aimed at creating environments more conducive to physical activity (PA) are an important component of strategies to improve population levels of PA. However, many potentially effective policies are not being broadly implemented. This study sought to identify potential policy/regulatory interventions targeting PA environments, and barriers/facilitators to their implementation at the Australian state/territory government level.Methods In-depth interviews were conducted with senior representatives from state/territory governments, statutory authorities and non-government organisations (n = 40) to examine participants\u27: 1) suggestions for regulatory interventions to create environments more conducive to PA; 2) support for preselected regulatory interventions derived from a literature review. Thematic and constant comparative analyses were conducted.Results Policy interventions most commonly suggested by participants fell into two areas: 1) urban planning and provision of infrastructure to promote active travel; 2) discouraging the use of private motorised vehicles. Of the eleven preselected interventions presented to participants, interventions relating to walkability/cycling and PA facilities received greatest support. Interventions involving subsidisation (of public transport, PA-equipment) and the provision of more public transport infrastructure received least support. These were perceived as not economically viable or unlikely to increase PA levels. Dominant barriers were: the powerful &lsquo;road lobby&rsquo;, weaknesses in the planning system and the cost of potential interventions. Facilitators were: the provision of evidence, collaboration across sectors, and synergies with climate change/environment agendas.Conclusion This study points to how difficult it will be to achieve policy change when there is a powerful &lsquo;road lobby&rsquo; and government investment prioritises road infrastructure over PA-promoting infrastructure. It highlights the pivotal role of the planning and transport sectors in implementing PA-promoting policy, however suggests the need for clearer guidelines and responsibilities for state and local government levels in these areas. Health outcomes need to be given more direct consideration and greater priority within non-health sectors.<br /

    Requirements of SLP76 tyrosines in ITAM and integrin receptor signaling and in platelet function in vivo

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    Src homology 2 domain–containing leukocyte phosphoprotein of 76 kD (SLP76), an adaptor that plays a critical role in platelet activation in vitro, contains three N-terminal tyrosine residues that are essential for its function. We demonstrate that mice containing complementary tyrosine to phenylalanine mutations in Y145 (Y145F) and Y112 and Y128 (Y112/128F) differentially regulate integrin and collagen receptor signaling. We show that mutation of Y145 leads to severe impairment of glycoprotein VI (GPVI)–mediated responses while preserving outside-in integrin signaling. Platelets from Y112/128F mice, although having mild defects in GPVI signaling, exhibit defective actin reorganization after GPVI or αIIbβ3 engagement. The in vivo consequences of these signaling defects correlate with the mild protection from thrombosis seen in Y112/128F mice and the near complete protection observed in Y145F mice. Using genetic complementation, we further demonstrate that all three phosphorylatable tyrosines are required within the same SLP76 molecule to support platelet activation by GPVI

    Pioglitazone for secondary prevention after ischemic stroke and transient ischemic attack: Rationale and design of the Insulin Resistance Intervention after Stroke Trial

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    Background: Recurrent vascular events remain a major source of morbidity and mortality after stroke or transient ischemic attack (TIA). The IRIS Trial is evaluating an approach to secondary prevention based on the established association between insulin resistance and increased risk for ischemic vascular events. Specifically, IRIS will test the effectiveness of pioglitazone, an insulin-sensitizing drug of the thiazolidinedione class, for reducing the risk for stroke and myocardial infarction (MI) among insulin resistant, nondiabetic patients with a recent ischemic stroke or TIA. Design: Eligible patients for IRIS must have had insulin resistance defined by a Homeostasis Model Assessment-Insulin Resistance \u3e3.0 without meeting criteria for diabetes. Within 6 months of the index stroke or TIA, patients were randomly assigned to pioglitazone (titrated from 15 to 45 mg/d) or matching placebo and followed for up to 5 years. The primary outcome is time to stroke or MI. Secondary outcomes include time to stroke alone, acute coronary syndrome, diabetes, cognitive decline, and all-cause mortality. Enrollment of 3,876 participants from 179 sites in 7 countries was completed in January 2013. Participant follow-up will continue until July 2015. Summary: The IRIS Trial will determine whether treatment with pioglitazone improves cardiovascular outcomes of nondiabetic, insulin-resistant patients with stroke or TIA. Results are expected in early 2016

    The Grizzly, December 1, 1978

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    Task Force Reviews Health Services; Bookstore Also Discussed • New Curriculum Approved • SAC Discusses New Frat & Allocations • Biology Department Alters Curriculum • A Good Editorial • Let\u27s See Co-Ed Dorms • A Mutually Advantageous Symbiosis • Letters to the Editor: Sleeping Awareness; Disturbing Guyana Attitudes • Portrait of the Professor: Dr. Patrick J. Mulvanny • Parking: Problem At Ursinus • If Zacharias Could See Us Now... • Think Snow • The Rocky Horror Show: A Celluloid Wasteland • Audio Corner: Loudspeakers • Thompson-Gay Soon To Be Theater • Logic & Dance • Drinking Myths • Hopes High For Hoops • Football Ends On Good Note • Ursinus Girls Drown Dickinson • Marathon Men Compete • Bears Net .500 Against Florida Foes • First Winter Weather Day ; Stimeling Exhibit To Be Presentedhttps://digitalcommons.ursinus.edu/grizzlynews/1008/thumbnail.jp
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