68 research outputs found

    Lower Mississippian Chert Development, Southern Midcontinent Region

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    The Lower Mississippian Boone Formation is a chert-bearing, fossiliferous limestone typically 100-115m. thick forming the Springfield Plateau across the tri-state region of northwestern Arkansas, southwestern Missouri, and northeastern Oklahoma. The Boone represents the maximum flooding, highstand, and regressive intervals of a single, third order transgressive-regressive carbonate cycle bounded by regional unconformities. Two types of chert occur in this formation, and provide the basis for subdivision of the Boone into informal lower and upper members in northern Arkansas. The lower Boone represents early Osagean maximum flooding conditions and consists of calcisiltites with interbedded dark, nodular chert. This chert exhibits compaction phenomena and shrinkage fractures, indicating a penecontemporaneous origin from reorganization of silica immediately below the sediment water interface prior to lithification of the carbonate sediments (Manger et al. 1988a). The upper Boone represents late Osagean highstand and regression and consists primarily of carbonate grainstones and packstones (Shelby 1986). This interval contains white, later diagenetic chert, interpreted as a groundwater phenomenon in which silica has replaced lithified carbonate along its bedding planes, replicating the fabric of the limestone (Manger and Shelby 2000). This later diagenetic chert replacement favors the finer grained intervals and replicates the fabric of the limestone being replaced. Previous studies have shown that the penecontemporaneous chert typically comprises 40-50% of the lower Boone interval, while the later diagenetic chert contribution to the upper Boone ranges from 30-95% (Liner 1979). Understanding chert development is unsettled, and has been the subject of debate, primarily involving the source of the silica producing the chert, and the mode of formation of the chert-bearing intervals. Geochemical analyses suggest a volcanic rather than biogenic source for the silica in the Boone Formation

    Hydrothermally Emplaced, Lower Mississippian, Tripolitic Chert and Its Possible Relationship to the Tri-State Lead-Zinc Mining District

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    Across the southern Ozark Region, northern Arkansas, southwestern Missouri, and northeastern Oklahoma, exposures of the Lower Mississippian Boone Formation and its equivalents exhibit well-developed tripolitic chert that has been mined, more or less continuously, for at least 80 years. The tripolitic chert is a replacement of an interval within the basal portion of the upper Boone Formation in Arkansas and Oklahoma, and equivalent to the Elsey Formation in Missouri. The movement of silica-rich, hydrothermal fluids appears to have been much like that of a confined aquifer. It followed the basal upper Boone Formation (Arkansas) = Elsey Formation (Missouri) and was bound below by an impermeable interval at the top of the lower Boone Formation (Arkansas) = Reeds Spring Formation (Missouri), and above by the base of the upper Boone Formation (Arkansas) = Burlington-Keokuk (Missouri). The first hydrothermal event incompletely silicified the basal upper Boone = Elsey Formation. After leaching of the remnant carbonate, thus forming the tripolitic chert, a second hydrothermal event deposited terminated and doubly terminated quartz crystals, and druse in the tripolitic chert voids. This hydrothermal event may have pro-duced the Mississippi Valley-Type (MVT) lead-zinc deposits in northeast Oklahoma and southwestern Missouri. The famous deposits at Picher, Oklahoma, and Joplin, Missouri, appear to be positioned in the apparent path of the hydrothermal fluid migration. While timing of these hydrothermal events is unclear, they may reflect lateral secretion produced by the Ouachita Orogeny in the Late Pennsylvanian

    Ï•\phi meson production in sNN\sqrt{s_{NN}} = 200 GeV Au+Au and pp collisions at RHIC

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    We present the results for the measurement of ϕ\phi meson production in sNN\sqrt{s_{NN}} = 200 GeV Au+Au and pp collisions at the Relativistic Heavy Ion Collider (RHIC). Using the event mixing technique, spectra and yields are obtained from the ϕ→K+K−\phi\to K^{+}K^{-} decay channel for different centrality bins in Au+Au collisions and in pp collisions. We observe that the spectrum shape in Au+Au collisions depends weakly on the centrality and the shape of the spectrum in pp collisions is significantly different from that in Au+Au collisions. In Au+Au collisions, the extracted yield of ϕ\phi meson is flat as a function of rapidity; The of ϕ\phi, extracted from the fit function to the spectra, shows a different behavior as a function of centrality than that of π−\pi^-, K−K^- and pˉ\bar{p}Comment: Proceedings for the 7th International Conference on Strangeness in Quark Matte

    Patterns of adherence to and compliance with the Portuguese smoke-free law in the leisure-hospitality sector

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    CIEC – Research Centre on Child Studies, UM (FCT R&D 317)Background: In 2008, the Portuguese smoke-free law came into effect including partial bans in the leisure-hospitality (LH) sector. The objective of the study is to assess the prevalence of smoking control policies (total ban, smoking permission and designated smoking areas) adopted by the LH sector in Portugal. The levels of noncompliance with each policy are investigated as well as the main factors associated with smoking permission and noncompliance with the law. Methods: Cross-sectional study conducted between January 2010 and May 2011. A random sample of venues was selected from the Portuguese LH sector database, proportionally stratified according to type, size and geographical area. All venues were assessed in loco by an observer. The independent effects of venues’ characteristics on smoking permission and the level of noncompliance with the law were explored using logistic regression. Results: Overall, 1.412 venues were included. Total ban policy was adopted by 75.9% of venues, while 8.4% had designated smoking areas. Smoking ban was more prevalent in restaurants (85.9%). Only 29.7% of discos/bars/pubs opted for complete ban. Full or partial smoking permission was higher in discos/bar/pubs (OR = 7.37; 95%CI 4.87 to 11.17). Noncompliance with the law was higher in venues allowing smoking and lower in places with complete ban (33.6% and 7.6% respectively, p, 0.001). Discos/bars/pubs with full smoking permission had the highest level of noncompliance (OR = 3.31; 95%CI 1.40 to 7.83). Conclusions: Our findings show a high adherence to smoking ban policy by the Portuguese LH sector. Nonetheless, one quarter of the venues is fully or partially permissive towards smoking, with the discos/bars/pubs considerably contributing to this situation. Venues with smoking permission policies were less compliant with the legislation. The implementation of a comprehensive smoke-free law, without any exceptions, is essential to effectively protect people from the second hand smoke.The work is part of a large Epidemiological Study on the Portuguese Tobacco Control Policy, developed by the Instituto de Medicina Preventiva da Faculdade de Medicina de Lisboa and supported, in its preliminary part, by the Direccao Geral da Saude (DGS) and, in the second part, by the national funding institution Fundacao para a Ciencia e Tecnologia (FCT). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

    Political dynamics promoting the incremental regulation of secondhand smoke: a case study of New South Wales, Australia

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    BACKGROUND: The history of governmental responses to the accumulation of scientific evidence about the harms of secondhand smoke (SHS) presents an intriguing case study of incremental public health policy development. Australia has long been considered a world-leader in progressive tobacco control policies, but in the last decade has fallen behind other jurisdictions in introducing SHS legislation that protects all workers. Bars, clubs and pubs remain the only public indoor spaces where smoking is legally permitted, despite SHS exposure in the hospitality industry being higher and affecting more people than in any other setting after domestic exposure. This paper examines the political dynamics that have shaped this incremental approach to SHS. METHODS: In-depth interviews with 21 key stakeholders in the state of New South Wales (NSW), including politicians, their advisors, health officials and tobacco control advocates, were conducted and subjected to thematic content analysis. Interviewees' comments provided insights into the dynamics surrounding the debates and outcomes of SHS legislative attempts and the current political environment, and about how to progress SHS legislation. RESULTS: SHS restrictions have been delayed by several broad factors: the influence of industry groups successfully opposing regulation; issue wear-out; and political perceptions that there is not a salient constituency demanding that smoking be banned in bars and clubs. Interviewees also provided suggestions of strategies that advocates might utilise to best overcome the current political inertia of incremental compromises and achieve timely comprehensive smoking bans. CONCLUSION: Advocates concerned to shorten the duration of incremental endgames must continue to insist that governments address SHS fundamentally as a health issue rather than making political concessions to industry groups, and should broaden and amplify community voices calling on governments to finish the job. Publicity to the growing number of state and national governments that have successfully implemented total bans over the past decade is likely to make incrementalism an increasingly unattractive political option

    Defining sepsis on the wards: results of a multi-centre point-prevalence study comparing two sepsis definitions

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    Our aim was to prospectively determine the predictive capabilities of SEPSIS-1 and SEPSIS-3 definitions in the emergency departments and general wards. Patients with National Early Warning Score (NEWS) of 3 or above and suspected or proven infection were enrolled over a 24-h period in 13 Welsh hospitals. The primary outcome measure was mortality within 30 days. Out of the 5422 patients screened, 431 fulfilled inclusion criteria and 380 (88%) were recruited. Using the SEPSIS-1 definition, 212 patients had sepsis. When using the SEPSIS-3 definitions with Sequential Organ Failure Assessment (SOFA) score ≥ 2, there were 272 septic patients, whereas with quickSOFA score ≥ 2, 50 patients were identified. For the prediction of primary outcome, SEPSIS-1 criteria had a sensitivity (95%CI) of 65% (54–75%) and specificity of 47% (41–53%); SEPSIS-3 criteria had a sensitivity of 86% (76–92%) and specificity of 32% (27–38%). SEPSIS-3 and SEPSIS-1 definitions were associated with a hazard ratio (95%CI) 2.7 (1.5–5.6) and 1.6 (1.3–2.5), respectively. Scoring system discrimination evaluated by receiver operating characteristic curves was highest for Sequential Organ Failure Assessment score (0.69 (95%CI 0.63–0.76)), followed by NEWS (0.58 (0.51–0.66)) (p < 0.001). Systemic inflammatory response syndrome criteria (0.55 (0.49–0.61)) and quickSOFA score (0.56 (0.49–0.64)) could not predict outcome. The SEPSIS-3 definition identified patients with the highest risk. Sequential Organ Failure Assessment score and NEWS were better predictors of poor outcome. The Sequential Organ Failure Assessment score appeared to be the best tool for identifying patients with high risk of death and sepsis-induced organ dysfunction

    Use of a pig model to demonstrate vulnerability of major neck vessels to inflicted trauma from common household items

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    Commonly available items including a ball point pen, a plastic knife, a broken wine bottle, and a broken wine glass were used to inflict stab and incised wounds to the necks of 3 previously euthanized Large White pigs. With relative ease, these items could be inserted into the necks of the pigs next to the jugular veins and carotid arteries. Despite precautions against the carrying of metal objects such as knives and nail files on board domestic and international flights, objects are still available within aircraft cabins that could be used to inflict serious and potentially life-threatening injuries. If airport and aircraft security measures are to be consistently applied, then consideration should be given to removing items such as glass bottles and glass drinking vessels. However, given the results of a relatively uncomplicated modification of a plastic knife, it may not be possible to remove all dangerous objects from aircraft. Security systems may therefore need to focus on measures such as increased surveillance of passenger behavior, rather than on attempting to eliminate every object that may serve as a potential weapon

    Reporting pupils' achievements to parents

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    Available from British Library Document Supply Centre- DSC:3214.05(DES-Circ--5/92) / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo

    Lithologic Stratigraphic Position, Sequence and Diagenetic History, Lower Mississippian Tripolitic Chert, Northern Arkansas and Southern Missouri

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    Tripolitic chert development in the southern Ozark region is associated with a third-order, transgressive-regressive cycle comprising St. Joe transgressive packstones, succeeded by lower Boone calcisiltites, with black, penecontemporaneous, nodular chert deposited during maximum flooding, overlain by basal upper Boone calcisiltites deposited during highstand. The onset of regression produced upper Boone packstones and grainstones with white-gray, later diagenetic chert reflecting groundwater replacement along bedding planes. Tripolitic chert is a product of the highstand calcisiltites at the base of the upper Boone Formation of Arkansas, and its equivalent, the Elsey Formation of southern Missouri. This tripolitic chert appears to reflect a hydrothermal event likely occurring after the emplacement processes of both Boone cherts that had ended by Chesterian time. After hydrothermal silicification, the interval experienced groundwater removal of most of the remaining carbonate leaving open porosity characteristic of tripolitic chert. A second hydrothermal event precipitated terminated and doubly terminated quartz crystals as well as quartz druse in the cavities produced by the earlier carbonate leaching from the tripolitic chert. Timing of the hydrothermal events is not clear, but they may reflect lateral secretion produced by the Ouachita Orogeny in the late Pennsylvanian
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