474 research outputs found

    Request to Release CEV Orion TSP Images Acquired at AEDC Tunnel 9

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    This document reviews the images that are requested for release from the Temperature Sensitive Paint tests of the Crew Exploration Vehicle (CEV) Orion that were conducted at the Arnold Engineering Development Center wind tunnel. Included is a description of the data, sample images, and graphs showing (1) Thermocouple T history under the paint layer at the location where the I/Iref is provided, and the Surface I/Iref history over the thermocouple

    Primary Sources of Polycyclic Aromatic Hydrocarbons to Streambed Sediment in Great Lakes Tributaries Using Multiple Lines of Evidence

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    Polycyclic aromatic hydrocarbons (PAHs) are among the most widespread and potentially toxic contaminants in Great Lakes (USA/Canada) tributaries. The sources of PAHs are numerous and diverse, and identifying the primary source(s) can be difficult. The present study used multiple lines of evidence to determine the likely sources of PAHs to surficial streambed sediments at 71 locations across 26 Great Lakes Basin watersheds. Profile correlations, principal component analysis, positive matrix factorization source-receptor modeling, and mass fractions analysis were used to identify potential PAH sources, and land-use analysis was used to relate streambed sediment PAH concentrations to different land uses. Based on the common conclusion of these analyses, coal-tar-sealed pavement was the most likely source of PAHs to the majority of the locations sampled. The potential PAH-related toxicity of streambed sediments to aquatic organisms was assessed by comparison of concentrations with sediment quality guidelines. The sum concentration of 16 US Environmental Protection Agency priority pollutant PAHs was 7.4-196 000 mu g/kg, and the median was 2600 mu g/kg. The threshold effect concentration was exceeded at 62% of sampling locations, and the probable effect concentration or the equilibrium partitioning sediment benchmark was exceeded at 41% of sampling locations. These results have important implications for watershed managers tasked with protecting and remediating aquatic habitats in the Great Lakes Basin.Environ Toxicol Chem2020;00:1-17. (c) 2020 The Authors.Environmental Toxicology and Chemistrypublished by Wiley Periodicals LLC on behalf of SETAC.Peer reviewe

    The influence of a major disaster on suicide risk in the population

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    The authors investigated the relationship between the September 11, 2001 terrorist attacks and suicide risk in New York City from 1990 to 2006. The average monthly suicide rate over the study period was 0.56 per 100,000 people. The monthly rate after September 2001 was 0.11 per 100,000 people lower as compared to the rate in the period before. However, the rate of change in suicide was not significantly different before and after the disaster, and regression discontinuity analysis indicated no change at this date. There was no net change in the suicide rate in New York City attributable to this disaster, suggesting that factors other than exposure to traumatic events (e.g., cultural norms, availability of lethal methods) may be key drivers of suicide risk in this context.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/64557/1/20473_ftp.pd

    A Geometrical Model for DNA Organization in Bacteria

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    Recent experimental studies have revealed that bacteria, such as C. crescentus, show a remarkable spatial ordering of their chromosome. A strong linear correlation has been found between the position of genes on the chromosomal map and their spatial position in the cellular volume. We show that this correlation can be explained by a purely geometrical model. Namely, self-avoidance of DNA, specific positioning of one or few DNA loci (such as origin or terminus) together with the action of DNA compaction proteins (that organize the chromosome into topological domains) are sufficient to get a linear arrangement of the chromosome along the cell axis. We develop a Monte-Carlo method that allows us to test our model numerically and to analyze the dependence of the spatial ordering on various physiologically relevant parameters. We show that the proposed geometrical ordering mechanism is robust and universal (i.e. does not depend on specific bacterial details). The geometrical mechanism should work in all bacteria that have compacted chromosomes with spatially fixed regions. We use our model to make specific and experimentally testable predictions about the spatial arrangement of the chromosome in mutants of C. crescentus and the growth-stage dependent ordering in E. coli

    Long-term Effects of Dieting: Is Weight Loss Related to Health?

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    "Success" in dieting interventions has traditionally been defined as weight loss. It is implicit in this definition that losing weight will lead to improved health, and yet, health outcomes are not routinely included in studies of diets. In this article, we evaluate whether weight loss improves health by reviewing health outcomes of long-term randomized controlled diet studies. We examine whether weight-loss diets lead to improved cholesterol, triglycerides, systolic and diastolic blood pressure, and fasting blood glucose and test whether the amount of weight lost is predictive of these health outcomes. Across all studies, there were minimal improvements in these health outcomes, and none of these correlated with weight change. A few positive effects emerged, however, for hypertension and diabetes medication use and diabetes and stroke incidence. We conclude by discussing factors that potentially confound the relationship between weight loss and health outcomes, such as increased exercise, healthier eating, and engagement with the health care system, and we provide suggestions for future research. © 2013 John Wiley & Sons Ltd

    Populist communication in the new media environment: a cross-regional comparative perspective

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    The changing terms of mediation place new demands, opportunities and risks on the performance of the political persona. Visibility has become a double-edged sword, leaving representatives vulnerable to exposure while new tools provide opportunities for emerging entrepreneurial actors. This double risk to elites’ mediated personas—exposure and challenge from entrepreneurs—renders their armour of authenticity dangerously fragile, which nourishes a public sense of being inefficaciously represented. It is this climate in which populism currently flourishes around the globe. Three primary criteria of mediated self-representation by politicians—visibility, authenticity and efficacy—form the focus of this paper: how do populists negotiate such demands in different democratic contexts, and wherein lies the symbiosis between populism and the new media environment suggested by the literature? To answer this, the paper compares two populist cases responding to different democratic contexts: UKIP, a right-wing party from an established democracy (UK), and the Economic Freedom Fighters (EFF), a left-wing party from a transitional democracy (South Africa). The objects of study are disruptive performances by these parties, which are considered emblematic manifestations of populist ideology as they establish a Manichaean relationship between the elite and populist actors who embody the people. The paper introduces disruption as a multi-faceted and significant analytical concept to explain the populist behaviour and strategies that underlie populist parties’ responses to the demands for visibility, authenticity and efficacy that the new media environment places upon political representatives. Using mixed methods with an interpretive focus, the paper paints a rich picture of the contexts, meanings and means of construction of populist performances

    Predictors of Time to Death After Terminal Withdrawal of Mechanical Ventilation in the ICU

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    Little information exists about the expected time to death after terminal withdrawal of mechanical ventilation. We sought to determine the independent predictors of time to death after withdrawal of mechanical ventilation. METHODS: We conducted a secondary analysis from a cluster randomized trial of an end-of-life care intervention. We studied 1,505 adult patients in 14 hospitals in Washington State who died within or shortly after discharge from an ICU following terminal withdrawal of mechanical ventilation (August 2003 to February 2008). Time to death and its predictors were abstracted from the patients' charts and death certificates. Predictors included demographics, proxies of severity of illness, life-sustaining therapies, and International Classification of Diseases, 9th ed., Clinical Modification codes. RESULTS: The median (interquartile range [IQR]) age of the cohort was 71 years (58-80 years), and 44% were women. The median (IQR) time to death after withdrawal of ventilation was 0.93 hours (0.25-5.5 hours). Using Cox regression, the independent predictors of a shorter time to death were nonwhite race (hazard ratio [HR], 1.17; 95% CI, 1.01-1.35), number of organ failures (per-organ HR, 1.11; 95% CI, 1.04-1.19), vasopressors (HR, 1.67; 95% CI, 1.49-1.88), IV fluids (HR, 1.16; 95% CI, 1.01-1.32), and surgical vs medical service (HR, 1.29; 95% CI, 1.06-1.56). Predictors of longer time to death were older age (per-decade HR, 0.95; 95% CI, 0.90-0.99) and female sex (HR, 0.86; 95% CI, 0.77-0.97). CONCLUSIONS: Time to death after withdrawal of mechanical ventilation varies widely, yet the majority of patients die within 24 hours. Subsequent validation of these predictors may help to inform family counseling at the end of life.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/85787/1/Cooke - Predictors of time to death after withdrawal.pd
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