1,318 research outputs found

    Warm H2_2 as a probe of massive accretion and feedback through shocks and turbulence across cosmic time

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    Galaxy formation depends on a complex interplay between gravitational collapse, gas accretion, merging, and feedback processes. Yet, after many decades of investigation, these concepts are poorly understood. This paper presents the argument that warm H2_2 can be used as a tool to unlock some of these mysteries. Turbulence, shocks and outflows, driven by star formation, AGN activity or inflows, may prevent the rapid buildup of star formation in galaxies. Central to our understanding of how gas is converted into stars is the process by which gas can dissipate its mechanical energy through turbulence and shocks in order to cool. H2_2 lines provide direct quantitative measurements of kinetic energy dissipation in molecular gas in galaxies throughout the Universe. Based on the detection of very powerful H2_2 lines from z = 2 galaxies and proto-clusters at the detection limits of {\it Spitzer}, we are confident that future far-IR and UV H2_2 observations will provide a wealth of new information and insight into galaxy evolution to high-z. Finally, at the very earliest epoch of star and galaxy formation, warm H2_2 may also provide a unique glimpse of molecular gas collapse at 7 << z << 12 in massive dark matter (DM) halos on their way to forming the very first galaxies. Such measurements are beyond the reach of existing and planned observatories.Comment: Submitted as a science White Paper to the Astronomy and Astrophysics Astro 2020 Decadal Survey call issued by the National Academies of Sciences, Engineering and Medicine (March 11 2019

    Embedding open data practice: Developing indicators on the institutionalisation of open data practice in two African governments

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    Final research report of the “Embedding open data practice: Developing indicators on the institutionalisation of open data practice in two African governments” project, which formed part of the World Wide Web Foundation’s "Emerging Impacts of Open Data in Developing Countries" Phase 2 initiative. In order to address the principle question of whether open data practice is being embedded, the project undertook a comparison of government open data in South Africa and Kenya, with a particular focus on open licensing as a key indicator of openness

    Application of automated electrical resistance sensors for measurement of corrosion rate of copper, bronze and iron in model indoor atmospheres containing short-chain volatile carboxylic acids

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    The corrosion rate of copper and bronze Cu-8. wt.%Sn increased rapidly when the concentration of formic or acetic acid in air reached about 300. ppb at 80% relative humidity (RH) and a temperature of 20. °C. It decreased slowly during the several days after pollutant removal due to the slow rate of pollutant desorption from the metal surfaces. Corrosion of these metals was barely affected by the acids at RH up to 60%. For iron, the critical concentration of formic acid in air which led to surface activation at 80% RH was between 1000 and 1590. ppb.</p

    RENEB accident simulation exercise

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    Purpose: The RENEB accident exercise was carried out in order to train the RENEB participants in coordinating and managing potentially large data sets that would be generated in case of a major radiological event. Materials and methods: Each participant was offered the possibility to activate the network by sending an alerting email about a simulated radiation emergency. The same participant had to collect, compile and report capacity, triage categorization and exposure scenario results obtained from all other participants. The exercise was performed over 27 weeks and involved the network consisting of 28 institutes: 21 RENEB members, four candidates and three non-RENEB partners. Results: The duration of a single exercise never exceeded 10 days, while the response from the assisting laboratories never came later than within half a day. During each week of the exercise, around 4500 samples were reported by all service laboratories (SL) to be examined and 54 scenarios were coherently estimated by all laboratories (the standard deviation from the mean of all SL answers for a given scenario category and a set of data was not larger than 3 patient codes). Conclusions: Each participant received training in both the role of a reference laboratory (activating the network) and of a service laboratory (responding to an activation request). The procedures in the case of radiological event were successfully established and tested

    Rule-Makers or Rule-Takers? Exploring the Transatlantic Trade and Investment Partnership

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    The Transatlantic Trade and Investment Partnership (TTIP) is an effort by the United States and the European Union to reposition themselves for a world of diffuse economic power and intensified global competition. It is a next-generation economic negotiation that breaks the mould of traditional trade agreements. At the heart of the ongoing talks is the question whether and in which areas the two major democratic actors in the global economy can address costly frictions generated by their deep commercial integration by aligning rules and other instruments. The aim is to reduce duplication in various ways in areas where levels of regulatory protection are equivalent as well as to foster wide-ranging regulatory cooperation and set a benchmark for high-quality global norms. In this volume, European and American experts explain the economic context of TTIP and its geopolitical implications, and then explore the challenges and consequences of US-EU negotiations across numerous sensitive areas, ranging from food safety and public procurement to economic and regulatory assessments of technical barriers to trade, automotive, chemicals, energy, services, investor-state dispute settlement mechanisms and regulatory cooperation. Their insights cut through the confusion and tremendous public controversies now swirling around TTIP, and help decision-makers understand how the United States and the European Union can remain rule-makers rather than rule-takers in a globalising world in which their relative influence is waning

    Differing clinical features between Japanese and Caucasian patients with myelodysplastic syndromes:Analysis from the International Working Group for Prognosis of MDS

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    Clinical features of myelodysplastic syndromes (MDS) could be influenced by many factors, such as disease intrinsic factors (e.g., morphologic, cytogenetic, molecular), extrinsic factors (e.g, management, environment), and ethnicity. Several previous studies have suggested such differences between Asian and European/USA countries. In this study, to elucidate potential differences in primary untreated MDS between Japanese (JPN) and Caucasians (CAUC), we analyzed the data from a large international database collected by the International Working Group for Prognosis of MDS (300 and 5838 patients, respectively). JPN MDS were significantly younger with more severe cytopenias, and cytogenetic differences: less del(5q) and more +1/+1q, -1/del(1p), der(1;7), -9/del(9q), del(16q), and del(20q). Although differences in time to acute myeloid leukemia transformation did not occur, a significantly better survival in JPN was demonstrated, even after the adjustment for age and FAB subtypes, especially in lower, but not in higher prognostic risk categories. Certain clinical factors (cytopenias, blast percentage, cytogenetic risk) had different impact on survival and time to transformation to leukemia between the two groups. Although possible confounding events (e.g., environment, diet, and access to care) could not be excluded, our results indicated the existence of clinically relevant ethnic differences regarding survival in MDS between JPN and CAUC patients. The good performance of the IPSS-R in both CAUC and JP patients underlines that its common risk model is adequate for CAUC and JP
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