944 research outputs found

    Characterization of surficial units on Mars using Viking orbiter multispectral image and thermal data

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    Albedo and thermal property correlations of the topography of Mars were conducted with emphases upon the types and origins of materials exposed in the central equatorial region. This area displays a wide variation in color, albedo and thermal properties, and is relatively free of dust and haze. The physical, mineralogical and elemental characteristics of this area are discussed

    Application of shock tubes to transonic airfoil testing at high Reynolds numbers

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    Performance analysis of a gas-driven shock tube shows that transonic airfoil flows with chord Reynolds numbers of the order of 100 million can be produced, with limitations being imposed by the structural integrity of the facility or the model. A study of flow development over a simple circular arc airfoil at zero angle of attack was carried out in a shock tube at low and intermediate Reynolds numbers to assess the testing technique. Results obtained from schlieren photography and airfoil pressure measurements show that steady transonic flows similar to those produced for the same airfoil in a wind tunnel can be generated within the available testing time in a shock tube with properly contoured test section walls

    A simple squeezer for removal of interstitial water from ocean sediments

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    A simple and inexpensive squeezer employed in the removal of interstitial water from ocean sediments has been designed. Squeezing is carried out with nitrogen at pressures of 500 to 1000 lb/in2 (35 to 70 kg/cm2). The apparatus is lined with teflon, thus insuring complete freedom from metallic contamination

    A Collaborative, Trilateral Approach to Bridging the Information Literacy Gap in Student Writing

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    As localized assessments confirm national findings that undergraduates struggle to integrate resources into research-based compositions effectively, data at one comprehensive public university indicate library sessions improve students’ ability to locate and evaluate information, but students continue to struggle with the “use” component of information literacy. This article presents a trilateral case study among librarians, faculty, and writing center administrators, emphasizing the intersection of programmatic partnerships, assessment, and pedagogical best practices. Our research shows a trilateral approach to information literacy increases efficacy and a sense of shared responsibility in support of student research where traditional bilateral approaches fall short

    Patient Safety and Quality Improvement Education for Paramedics: Peacticing What We Preach

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    Our patients expect and deserve safe, high-quality care. Paramedics have a personal responsibility for providing safe care, regardless of previous education or regulatory framework. The onus is on us all to ensure that paramedics are adequately prepared to address this responsibility

    Survey of sediment quality in Sabine Lake, Texas and vicinity

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    The toxicity of sediments in Sabine Lake, Texas, and adjoining Intracoastal Waterway canals was determined as part of bioeffects assessment studies managed by NOAA’s National Status and Trends Program. The objectives of the survey were to determine: (1) the incidence and degree of toxicity of sediments throughout the study area; (2) the spatial patterns (or gradients) in chemical contamination and toxicity, if any, throughout the study area; (3) the spatial extent of chemical contamination and toxicity; and (4) the statistical relationships between measures of toxicity and concentrations of chemicals in the sediments. Surficial sediment samples were collected during August, 1995 from 66 randomly-chosen locations. Laboratory toxicity tests were performed as indicators of potential ecotoxicological effects in sediments. A battery of tests was performed to generate information from different phases (components) of the sediments. Tests were selected to represent a range in toxicological endpoints from acute to chronic sublethal responses. Toxicological tests were conducted to measure: reduced survival of adult amphipods exposed to solid-phase sediments; impaired fertilization success and abnormal morphological development in gametes and embryos, respectively, of sea urchins exposed to pore waters; reduced metabolic activity of a marine bioluminescent bacteria exposed to organic solvent extracts; and induction of a cytochrome P-450 reporter gene system in exposures to solvent extracts of the sediments. Chemical analyses were performed on portions of each sample to quantify the concentrations of trace metals, polynuclear aromatic hydrocarbons, and chlorinated organic compounds. Correlation analyses were conducted to determine the relationships between measures of toxicity and concentrations of potentially toxic substances in the samples. Based upon the compilation of results from chemical analyses and toxicity tests, the quality of sediments in Sabine Lake and vicinity did not appear to be severely degraded. Chemical concentrations rarely exceeded effects-based numerical guidelines, suggesting that toxicant-induced effects would not be expected in most areas. None of the samples was highly toxic in acute amphipod survival tests and a minority (23%) of samples were highly toxic in sublethal urchin fertilization tests. Although toxic responses occurred frequently (94% of samples) in urchin embryo development tests performed with 100% pore waters, toxicity diminished markedly in tests done with diluted pore waters. Microbial bioluminescent activity was not reduced to a great degree (no EC50 <0.06 mg/ml) and cytochrome P-450 activity was not highly induced (6 samples exceeded 37.1 ug/g benzo[a]pyrene equivalents) in tests done with organic solvent extracts. Urchin embryological development was highly correlated with concentrations of ammonia and many trace metals. Cytochrome P450 induction was highly correlated with concentrations of a number of classes of organic compounds (including the polynuclear aromatic hydrocarbons and chlorinated compounds). (PDF contains 51 pages

    Balance Assessment Using a Smartwatch Inertial Measurement Unit with Principal Component Analysis for Anatomical Calibration

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    Balance assessment, or posturography, tracks and prevents health complications for a variety of groups with balance impairment, including the elderly population and patients with traumatic brain injury. Wearables can revolutionize state-of-the-art posturography methods, which have recently shifted focus to clinical validation of strictly positioned inertial measurement units (IMUs) as replacements for force-plate systems. Yet, modern anatomical calibration (i.e., sensor-to-segment alignment) methods have not been utilized in inertial-based posturography studies. Functional calibration methods can replace the need for strict placement of inertial measurement units, which may be tedious or confusing for certain users. In this study, balance-related metrics from a smartwatch IMU were tested against a strictly placed IMU after using a functional calibration method. The smartwatch and strictly placed IMUs were strongly correlated in clinically relevant posturography scores (r = 0.861–0.970, p \u3c 0.001). Additionally, the smartwatch was able to detect significant variance (p \u3c 0.001) between pose-type scores from the mediolateral (ML) acceleration data and anterior-posterior (AP) rotation data. With this calibration method, a large problem with inertial-based posturography has been addressed, and wearable, “at-home” balance-assessment technology is within possibility

    Elevated cardiovascular risk among adults with obstructive and restrictive airway functioning in the United States: a cross-sectional study of the National Health and Nutrition Examination Survey from 2007-2010

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    BACKGROUND: Reasons for the excess risk for cardiovascular disease among people with chronic obstructive pulmonary disease remain unclear. Our objective was to examine the cardiovascular risk profile for adults with obstructive and restrictive impairments of lung functioning in a representative sample of adults from the United States. METHODS: We used data from adults aged 20-79 years who participated in the National Health and Nutrition Examination Survey from 2007 to 2010 and had a pulmonary function test. The severity of obstructive impairment was defined by adapting the Global Initiative for Chronic Obstructive Lung Disease criteria. RESULTS: Among 7249 participants, 80.9% had a normal pulmonary function test, 5.7% had a restrictive impairment, 7.9% had mild obstructive impairment, and 5.5% had moderate or severe/very severe obstructive impairment. Participants with obstructive impairment had high rates of smoking and increased serum concentrations of cotinine. Compared to participants with normal pulmonary functioning, participants with at least moderate obstructive impairment had elevated concentrations of C-reactive protein but lower concentrations of total cholesterol and non-high-density lipoprotein cholesterol. Among participants aged 50-74 years, participants with at least a moderate obstructive impairment or a restrictive impairment had an elevated predicted 10-year risk for cardiovascular disease. CONCLUSIONS: The high rates of smoking among adults with impaired pulmonary functioning, particularly those with obstructive impairment, point to a need for aggressive efforts to promote smoking cessation in these adults. In addition, adults with restrictive impairment may require increased attention to and fine-tuning of their cardiovascular risk profile

    Trends in the Use, Sociodemographic Correlates, and Undertreatment of Prescription Medications for Chronic Obstructive Pulmonary Disease among Adults with Chronic Obstructive Pulmonary Disease in the United States from 1999 to 2010

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    BACKGROUND: The extent to which patients with COPD are receiving indicated treatment with medications to improve lung function and recent trends in the use of these medications is not well documented in the United States. The objective of this study was to examine trends in prescription medications for COPD among adults in the United States from 1999 to 2010. METHODS: We performed a trend analysis using data from up to 1426 participants aged ≥20 years with self-reported COPD from six national surveys (National Health and Nutrition Examination Survey 1999-2010). RESULTS: During 2009-2010, the age-adjusted percentage of participants who used any kind of medication was 44.2%. Also during 2009-2010, the most commonly used medications were short-acting agents (36.0%), inhaled corticosteroids (ICS) (18.3%), and LABAs (16.7%). The use of long-acting beta-2 agonists (LABAs) (p for trend CONCLUSION: The percentages of adults with COPD who reported having various classes of prescription medications that improve airflow limitations changed markedly from 1999-2000 to 2009-2010. However, many adults with COPD did not report having recommended prescription medications

    Deep space 2: The Mars Microprobe Mission

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    The Mars Microprobe Mission will be the second of the New Millennium Program's technology development missions to planetary bodies. The mission consists of two penetrators that weigh 2.4 kg each and are being carried as a piggyback payload on the Mars Polar Lander cruise ring. The spacecraft arrive at Mars on December 3, 1999. The two identical penetrators will impact the surface at similar to 190 m/s and penetrate up to 0.6 m. They will land within 1 to 10 km of each other and similar to 50 km from the Polar Lander on the south polar layered terrain. The primary objective of the mission is to demonstrate technologies that will enable future science missions and, in particular, network science missions. A secondary goal is to acquire science data. A subsurface evolved water experiment and a thermal conductivity experiment will estimate the water content and thermal properties of the regolith. The atmospheric density, pressure, and temperature will be derived using descent deceleration data. Impact accelerometer data will be used to determine the depth of penetration, the hardness of the regolith, and the presence or absence of 1.0 cm scale layers
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