Beetroot Juice and Cerebrovascular Hemodynamics in Young Adults with a History of Concussion: Preliminary Findings

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Vascular Function following a High Fat Meal with Resistance Exercise

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Lethal Parasites in Oysters from Coastal Georgia with Discussion of Disease and Management Implications

Extensive mortalities of oysters, Crassostrea virginica, occurred from 1985 through 1987 in coastal waters of Georgia. Fluid thioglycolate cultures of oysters collected from 16 of 17 locations revealed infections by the apicomplexan parasite Perkinsus marinus. An ascetosporan parasite, Haplosporidium nelsoni, was also observed in histopathological examination of oysters from 4 of the locations. While the range of H. nelsoni currently is recognized as the east coast of the United States from Maine to Florida, this is the first report of the parasite in Georgia waters. This paper documents the occurrence of these two lethal parasites in oysters from coastal waters of Georgia, along with potential disease and management implications. Results of an earlier independent and previously unpublished survey are also discussed which document the presence of P. marinus in Georgia as early as 1966

Fluoroscopic imaging overestimates the screw tip to subchondral bone distance in a cadaveric model of slipped capital femoral epiphysis

PURPOSE: Intra-operative imaging plays a key role in screw placement for slipped capital femoral epiphysis (SCFE). Complications have been associated with inadequate screw position. The purpose of this study was to evaluate computed tomography (CT) (3D fluoroscopy) and standard fluoroscopy (C-arm) images as compared with direct anatomic measurement to determine final screw position in a cadaveric SCFE model. METHODS: Osteotomy with pinning was performed at the physeal scar in ten cadaveric hips. A standardised approach-withdrawal technique was performed with C-arm images taken at 15 degrees increments. We also obtained a CT (3D fluoroscopy) scan of each hip. The screw tip-subchondral bone (STSB) distance was measured on digital imaging software and also with a digital calliper directly when the femoral head was cut in plane to expose the STSB distance anatomically. Statistical analysis included t-tests and Fisher\u27s exact test. RESULTS: Moderate SCFE osteotomies were achieved with a mean Southwick angle (39.5 degrees +/- 7 degrees ). The 60 degrees fluoroscopic image was found to be the most representative image (41% of the time) compared with both anteroposterior (AP) and lateral images (8% and 21%). Both fluoroscopy (2.7 +/- 0.8 mm, p \u3c 0.001) and CT (1.6 +/- 0.7 mm, p = 0.03) overestimated the STSB distance compared with direct measurement (0.94 +/- 0.51 mm). Two-thirds (67%) of CT measurements were within 1 mm of the cadaveric measurement, while only 20% of C-arm measurements fulfilled this criterion (p = 0.04). CONCLUSIONS: Both standard fluoroscopy and CT overestimated the STSB distance when compared with direct measurement in a cadaveric model of SCFE. Surgeons should be aware of the limitations of intra-operative imaging to determine the STSB distance. We suggest that using the known pitch of a screw (2.9 mm in a 7.3-mm cannulated screw) as an intra-operative tool to help guide screw placement

Sex Differences in the Hemodynamic Response to Arm Elevation

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Denitrification and inference of nitrogen sources in the karstic Floridan Aquifer

Aquifer denitrification is among the most poorly constrained fluxes in global and regional nitrogen budgets. The few direct measurements of denitrification in groundwaters provide limited information about its spatial and temporal variability, particularly at the scale of whole aquifers. Uncertainty in estimates of denitrification may also lead to underestimates of its effect on isotopic signatures of inorganic N, and thereby confound the inference of N source from these data. In this study, our objectives are to quantify the magnitude and variability of denitrification in the Upper Floridan Aquifer (UFA) and evaluate its effect on N isotopic signatures at the regional scale. Using dual noble gas tracers (Ne, Ar) to generate physical predictions of N<sub>2</sub> gas concentrations for 112 observations from 61 UFA springs, we show that excess (i.e. denitrification-derived) N<sub>2</sub> is highly variable in space and inversely correlated with dissolved oxygen (O<sub>2</sub>). Negative relationships between O<sub>2</sub> and δ<sup>15</sup>N<sub>NO3</sub> across a larger dataset of 113 springs, well-constrained isotopic fractionation coefficients, and strong <sup>15</sup>N:<sup>18</sup>O covariation further support inferences of denitrification in this uniquely organic-matter-poor system. Despite relatively low average rates, denitrification accounted for 32 % of estimated aquifer N inputs across all sampled UFA springs. Back-calculations of source δ<sup>15</sup>N<sub>NO3</sub> based on denitrification progression suggest that isotopically-enriched nitrate (NO<sub>3</sub><sup>–</sup>) in many springs of the UFA reflects groundwater denitrification rather than urban- or animal-derived inputs

Measuring Early Child Development across Low and Middle-Income Countries: A Systematic Review

The Sustainable Development Goals mandate that by 2030, all children should have access to quality early child development opportunities, healthcare and pre-primary education (United Nations, 2015). Yet validated measures of ECD in low and middle income countries (LMICs) are rare. To address this gap, a Systematic Review (SR) of measures available to profile the development of children between the ages of 0-5 years in LMICs was undertaken. Drawing on education, psychology and health databases, we identified reliable, valid or measures adapted for use in LMICs for either assessments of children’s development or their learning environments. The inclusion criteria were (1) peer reviewed papers published between January 2009 and May 2019; (2) assessment tools used to measure cognitive/language development or the early years or home environment in at least one LMIC; (3) report of the psychometric properties (validity and reliability) of the tool, and/or description of the cultural adaptability/translation process undertaken before applying it to a LMIC. Two hundred and forty-nine available records published in the last decade in peer-review journals and nine relevant systematic literature reviews were identified. Fifty-seven records were qualitatively synthesized based on their psychometric properties and cultural adaptation. Forty-three tools were reviewed utilising twelve criteria. Five elements of analysis present in Table 2 and 3 (study, population tested, validity, reliability and cultural adaptability/translation) focused on the tools’ psychometric properties and previous application in LMICs. A further seven dimensions outlined in Tables 4 and 5 identified specific characteristics of the tools from target age, administration method, domains, battery, accessibility, language and country/institution. We suggest these twelve key considerations for the selection of measurement tools that are applicable to effectively assess ECD in LMICs

Physical Function, Cognitive Function, and Aortic Stiffness in Older Adults

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Understanding the power of the prime minister : structure and agency in models of prime ministerial power

Understanding the power of the prime minister is important because of the centrality of the prime minister within the core executive of British government, but existing models of prime ministerial power are unsatisfactory for various reasons. This article makes an original contribution by providing an overview and critique of the dominant models of prime ministerial power, highlighting their largely positivist bent and the related problem of the prevalence of overly parsimonious conceptions of the structural contexts prime ministers face. The central argument the paper makes is that much of the existing literature on prime ministerial power is premised on flawed understandings of the relationship between structure and agency, that this leads to misunderstandings of the real scope of prime ministerial agency, as well as its determinants, and that this can be rectified by adopting a strategic-relational view of structure and agency

The Monitoring and Assessment Plan (MAP) Greater Everglades Wetlands Module- Landscape Pattern- Ridge, Slough, and Tree Island Mosaics: Year 1 Annual Report

In the current managed Everglades system, the pre-drainage, patterned mosaic of sawgrass ridges, sloughs and tree islands has been substantially altered or reduced largely as a result of human alterations to historic ecological and hydrological processes that sustained landscape patterns. The pre-compartmentalization ridge and slough landscape was a mosaic of sloughs, elongated sawgrass ridges (50-200m wide), and tree islands. The ridges and sloughs and tree islands were elongated in the direction of the water flow, with roughly equal area of ridge and slough. Over the past decades, the ridge-slough topographic relief and spatial patterning have degraded in many areas of the Everglades. Nutrient enriched areas have become dominated by Typha with little topographic relief; areas of reduced flow have lost the elongated ridge-slough topography; and ponded areas with excessively long hydroperiods have experienced a decline in ridge prevalence and shape, and in the number of tree islands (Sklar et al. 2004, Ogden 2005)