WorldWideScience

Sample records for inch-scale surface elevation

  1. Iowa Bedrock Surface Elevation

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — This Digital Elevation Model (DEM) of the bedrock surface elevation in Iowa was compiled using all available data, principally information from GEOSAM, supplemented...

  2. Tanzania Elevation and Surface Characteristics

    Data.gov (United States)

    US Agency for International Development — The dataset displays Elevation, Slope, Aspect, Topographic Position Index, Terrain Ruggedness, and Roughness based on Shuttle Radar Topography Mission (SRTM) (3...

  3. Cokriging surface elevation and seismic refraction data for bedrock topography

    International Nuclear Information System (INIS)

    Nyquist, J.E.; Doll, W.E.; Davis, R.K.; Hopkins, R.A.

    1992-01-01

    Analysis of seismic refraction data collected at a proposed site of the Advanced Neutron Source (ANS) Facility showed a strong correlation between surface and bedrock topography. By combining seismically determined bedrock elevation data with surface elevation data using cokriging, we were able to significantly improve our map of bedrock topography without collecting additional seismic data

  4. Roosevelt Island Bedrock and Surface Elevations, Version 1

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set consists of bedrock and surface elevation readings taken by ground penetrating radar and Global Positioning System (GPS) on Roosevelt Island, an ice...

  5. Measuring the role of seagrasses in regulating sediment surface elevation.

    Science.gov (United States)

    Potouroglou, Maria; Bull, James C; Krauss, Ken W; Kennedy, Hilary A; Fusi, Marco; Daffonchio, Daniele; Mangora, Mwita M; Githaiga, Michael N; Diele, Karen; Huxham, Mark

    2017-09-20

    Seagrass meadows provide numerous ecosystem services and their rapid global loss may reduce human welfare as well as ecological integrity. In common with the other 'blue carbon' habitats (mangroves and tidal marshes) seagrasses are thought to provide coastal defence and encourage sediment stabilisation and surface elevation. A sophisticated understanding of sediment elevation dynamics in mangroves and tidal marshes has been gained by monitoring a wide range of different sites, located in varying hydrogeomorphological conditions over long periods. In contrast, similar evidence for seagrasses is sparse; the present study is a contribution towards filling this gap. Surface elevation change pins were deployed in four locations, Scotland, Kenya, Tanzania and Saudi Arabia, in both seagrass and unvegetated control plots in the low intertidal and shallow subtidal zone. The presence of seagrass had a highly significant, positive impact on surface elevation at all sites. Combined data from the current work and the literature show an average difference of 31 mm per year in elevation rates between vegetated and unvegetated areas, which emphasizes the important contribution of seagrass in facilitating sediment surface elevation and reducing erosion. This paper presents the first multi-site study for sediment surface elevation in seagrasses in different settings and species.

  6. Measuring the role of seagrasses in regulating sediment surface elevation

    KAUST Repository

    Potouroglou, Maria

    2017-09-13

    Seagrass meadows provide numerous ecosystem services and their rapid global loss may reduce human welfare as well as ecological integrity. In common with the other \\'blue carbon\\' habitats (mangroves and tidal marshes) seagrasses are thought to provide coastal defence and encourage sediment stabilisation and surface elevation. A sophisticated understanding of sediment elevation dynamics in mangroves and tidal marshes has been gained by monitoring a wide range of different sites, located in varying hydrogeomorphological conditions over long periods. In contrast, similar evidence for seagrasses is sparse; the present study is a contribution towards filling this gap. Surface elevation change pins were deployed in four locations, Scotland, Kenya, Tanzania and Saudi Arabia, in both seagrass and unvegetated control plots in the low intertidal and shallow subtidal zone. The presence of seagrass had a highly significant, positive impact on surface elevation at all sites. Combined data from the current work and the literature show an average difference of 31 mm per year in elevation rates between vegetated and unvegetated areas, which emphasizes the important contribution of seagrass in facilitating sediment surface elevation and reducing erosion. This paper presents the first multi-site study for sediment surface elevation in seagrasses in different settings and species.

  7. Note on the surface wave due to the prescribed elevation

    Indian Academy of Sciences (India)

    Home; Journals; Pramana – Journal of Physics; Volume 62; Issue 1. Note on the surface wave due to the prescribed elevation. Niranjan Das. Brief Reports Volume 62 Issue 1 January 2004 pp 135-142. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/pram/062/01/0135-0142 ...

  8. Note on the surface wave due to the prescribed elevation

    Indian Academy of Sciences (India)

    oscillatory motion with the increase of time, leaving behind the highest elevation initially. On the other hand in case of spiral cyclonic motion for which the sea surface experiences the elliptical pressure distribution, the motion diminishes as g the ac- celeration due to gravity diminishes and oscillates with the variation of time.

  9. Geodetic Imaging of Marsh Surface Elevation with Terrestrial Laser Scanning

    Science.gov (United States)

    Nguyen, C. T.; Starek, M. J.; Gibeaut, J. C.; Lord, A.

    2015-12-01

    The resilience of marshes to a rising sea is dependent on their elevation response. Given the level of precision required to measure minute changes in marsh elevation over time, survey methods have to be adapted to minimize impacts to the sediment surface. Current approaches include Surface Elevation Tables (SETs), which are used to monitor wetland surface change with respect to an in situ vertical benchmark. Although SETs have been proven as an effective technique to track subtle sedimentation rates (RTK GPS for comparison. Grand Bay in Mississippi USA is one of the most biologically productive estuarine ecosystems in the Gulf of Mexico. The study region is covered by dense and tall saw-grass that makes it a challenging environment for bare-earth mapping. For this survey, a Riegl VZ-400 TLS (1550 nm wavelength) was utilized. The system is capable of recording multiple returns per a transmitted pulse (up to 15) and provides full-waveform output for signal post-processing to extract returns. The objectives of the study are twofold: 1) examine impacts of TLS survey design, scan angle and scan density on marsh elevation mapping; 2) assess the capabilities of multiple-echo and full-waveform TLS data to extract the bare-earth surface below the dense vegetation. This presentation will present results of the study including the developed TLS survey protocol and data processing workflow, details on waveform and multi-echo approaches for ground point detection, and a discussion on error analysis and challenges for measuring marsh surface elevation with TLS.

  10. The surface elevation table: marker horizon method for measuring wetland accretion and elevation dynamics

    Science.gov (United States)

    Callaway, John C.; Cahoon, Donald R.; Lynch, James C.

    2014-01-01

    Tidal wetlands are highly sensitive to processes that affect their elevation relative to sea level. The surface elevation table–marker horizon (SET–MH) method has been used to successfully measure these processes, including sediment accretion, changes in relative elevation, and shallow soil processes (subsidence and expansion due to root production). The SET–MH method is capable of measuring changes at very high resolution (±millimeters) and has been used worldwide both in natural wetlands and under experimental conditions. Marker horizons are typically deployed using feldspar over 50- by 50-cm plots, with replicate plots at each sampling location. Plots are sampled using a liquid N2 cryocorer that freezes a small sample, allowing the handling and measurement of soft and easily compressed soils with minimal compaction. The SET instrument is a portable device that is attached to a permanent benchmark to make high-precision measurements of wetland surface elevation. The SET instrument has evolved substantially in recent decades, and the current rod SET (RSET) is widely used. For the RSET, a 15-mm-diameter stainless steel rod is pounded into the ground until substantial resistance is achieved to establish a benchmark. The SET instrument is attached to the benchmark and leveled such that it reoccupies the same reference plane in space, and pins lowered from the instrument repeatedly measure the same point on the soil surface. Changes in the height of the lowered pins reflect changes in the soil surface. Permanent or temporary platforms provide access to SET and MH locations without disturbing the wetland surface.

  11. Inclusion of Solar Elevation Angle in Land Surface Albedo Parameterization Over Bare Soil Surface.

    Science.gov (United States)

    Zheng, Zhiyuan; Wei, Zhigang; Wen, Zhiping; Dong, Wenjie; Li, Zhenchao; Wen, Xiaohang; Zhu, Xian; Ji, Dong; Chen, Chen; Yan, Dongdong

    2017-12-01

    Land surface albedo is a significant parameter for maintaining a balance in surface energy. It is also an important parameter of bare soil surface albedo for developing land surface process models that accurately reflect diurnal variation characteristics and the mechanism behind the solar spectral radiation albedo on bare soil surfaces and for understanding the relationships between climate factors and spectral radiation albedo. Using a data set of field observations, we conducted experiments to analyze the variation characteristics of land surface solar spectral radiation and the corresponding albedo over a typical Gobi bare soil underlying surface and to investigate the relationships between the land surface solar spectral radiation albedo, solar elevation angle, and soil moisture. Based on both solar elevation angle and soil moisture measurements simultaneously, we propose a new two-factor parameterization scheme for spectral radiation albedo over bare soil underlying surfaces. The results of numerical simulation experiments show that the new parameterization scheme can more accurately depict the diurnal variation characteristics of bare soil surface albedo than the previous schemes. Solar elevation angle is one of the most important factors for parameterizing bare soil surface albedo and must be considered in the parameterization scheme, especially in arid and semiarid areas with low soil moisture content. This study reveals the characteristics and mechanism of the diurnal variation of bare soil surface solar spectral radiation albedo and is helpful in developing land surface process models, weather models, and climate models.

  12. Use of cokriging to estimate surface air temperature from elevation

    Science.gov (United States)

    Ishida, T.; Kawashima, S.

    1993-09-01

    Surface air temperature in central Japan was predicted from the temperature recordings from sensors in the Automated Meteorological Data Acquisition System (AMeDAS), using seven different procedures: the usual simple and universal kriging and cokriging estimators, the traditional regression analysis and the inverse distance weighted method. The cokriging estimator integrated digital elevation data as well as the air temperature readings. The performance of the procedures was evaluated and compared using cross-validation. The kriging estimator provided a better estimate than the traditional regression analysis that treated the data as spatially independent observations. The kriging estimate was also better than the inverse distance weighted method. Further improvement in the estimation accuracy was achieved by using cokriging procedures because of high correlation of air temperature with elevation. The accuracy of spatial prediction decreased due to nocturnal cooling in winter and daytime heating in summer. This decrease implies that a strong radiation balance at the surface, whether positive or negative, causes a relatively short-range variation in surface air temperature through the effects of local environments.

  13. Competing effects of surface albedo and orographic elevated heating on regional climate

    Science.gov (United States)

    Hu, Shineng; Boos, William R.

    2017-07-01

    All else being equal, a given atmospheric pressure level is thought to be warmer over a plateau than over surrounding nonelevated terrain because of orographic "elevated heating." However, elevated surfaces are also typically brighter due to reduced vegetation and increased ice cover. Here we assess the degree to which surface albedo compensates for orographic elevated heating. We confirm that land surface albedo generally increases with surface elevation in observations. Using a cloud system-resolving model, we show that increased surface albedo strongly compensates for orographic elevated heating in radiative-convective equilibrium. A nonelevated surface with the albedo of modern India would enter a runaway greenhouse regime without ventilation by monsoonal winds, while a surface with the albedo and elevation of Tibet would achieve a cooler radiative-convective equilibrium. Surface albedo changes may thus be just as important as surface elevation changes for the evolution of low-latitude regional climate throughout Earth's history.

  14. Effect of DS Concentration on the PRO Performance Using a 5-Inch Scale Cellulose Triacetate-Based Hollow Fiber Membrane Module

    Directory of Open Access Journals (Sweden)

    Masahiro Yasukawa

    2018-05-01

    Full Text Available In this study, pressure-retarded osmosis (PRO performance of a 5-inch scale cellulose triacetate (CTA-based hollow fiber (HF membrane module was evaluated under a wide range of operating conditions (0.0–6.0 MPa of applied pressure, 0.5–2.0 L/min feed solution (FS inlet flow rate, 1.0–6.0 L/min DS inlet flow rate and 0.1–0.9 M draw solution (DS concentration by using a PRO/reverse osmosis (RO hybrid system. The subsequent RO system for DS regeneration enabled the evaluation of the steady-stated module performance. In the case of pilot-scale module operation, since the DS dilution and the feed solution (FS up-concentration had occurred and was not negligible, unlike the lab-scale experiment, PRO performance strongly depended on operating conditions such as inlet flow rates of both the DS and FS concentration. To compare the module performance with different configurations, we proposed a converted parameter in which a difference of the packing density between the spiral wound (SW and the HF module was fairly considered. In the case of HF configuration, because of high packing density, volumetric-based performance was higher than that of SW module, that is, the required number of the module would be less than that of SW module in a full-scale PRO plant.

  15. IceBridge UAF Lidar Profiler L1B Geolocated Surface Elevation Triplets

    Data.gov (United States)

    National Aeronautics and Space Administration — The NASA IceBridge UAF Lidar Profiler L1B Geolocated Surface Elevation Triplets data set contains surface profiles of Alaska Glaciers acquired using the airborne...

  16. IceBridge Riegl Laser Altimeter L2 Geolocated Surface Elevation Triplets V001

    Data.gov (United States)

    National Aeronautics and Space Administration — The IceBridge Riegl Laser Altimeter L2 Geolocated Surface Elevation Triplets (ILUTP2) data set contains surface range values for Antarctica and Greenland derived...

  17. IceBridge Riegl Laser Altimeter L2 Geolocated Surface Elevation Triplets

    Data.gov (United States)

    National Aeronautics and Space Administration — The IceBridge Riegl Laser Altimeter L2 Geolocated Surface Elevation Triplets (ILUTP2) data set contains surface range values for Antarctica and Greenland derived...

  18. Field verification of ADCP surface gravity wave elevation spectra

    NARCIS (Netherlands)

    Hoitink, A.J.F.; Peters, H.C.; Schroevers, M.

    2007-01-01

    Acoustic Doppler current profilers (ADCPs) can measure orbital velocities induced by surface gravity waves, yet the ADCP estimates of these velocities are subject to a relatively high noise level. The present paper introduces a linear filtration technique to significantly reduce the influence of

  19. Surface Elevation and Ice Thickness, Western Marie Byrd Land, Antarctica, Version 1

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set provides surface elevation and ice thickness data for a portion of the Marie Byrd Land sector of West Antarctica, including the Ford Ranges, the...

  20. An experimental study of the surface elevation probability distribution and statistics of wind-generated waves

    Science.gov (United States)

    Huang, N. E.; Long, S. R.

    1980-01-01

    Laboratory experiments were performed to measure the surface elevation probability density function and associated statistical properties for a wind-generated wave field. The laboratory data along with some limited field data were compared. The statistical properties of the surface elevation were processed for comparison with the results derived from the Longuet-Higgins (1963) theory. It is found that, even for the highly non-Gaussian cases, the distribution function proposed by Longuet-Higgins still gives good approximations.

  1. Control and perception of balance at elevated and sloped surfaces.

    Science.gov (United States)

    Simeonov, Peter I; Hsiao, Hongwei; Dotson, Brian W; Ammons, Douglas E

    2003-01-01

    Understanding roof-work-related risk of falls and developing low-cost, practical engineering controls for reducing this risk remain in high demand in the construction industry. This study investigated the effects of the roof work environment characteristics of surface slope, height, and visual reference on standing balance in construction workers. The 24 participants were tested in a laboratory setting at 4 slopes (0 degrees, 18 degrees, 26 degrees, and 34 degrees), 2 heights (0, 3 m), and 2 visual conditions (with and without visual references). Postural sway characteristics were calculated using center of pressure recordings from a force platform. Workers' perceptions of postural sway and instability were also evaluated. The results indicated that slope and height synergistically increased workers' standing postural instability. Workers recognized the individual destabilizing effects of slope and height but did not recognize the synergistic effect of the two. Visual references significantly reduced the destabilizing effects of height and slope. Actual and potential applications of this research include the use of temporary level work surfaces and proximal vertical reference structures as postural instability control measures during roofing work.

  2. High-resolution pattern of mangrove species distribution is controlled by surface elevation

    Science.gov (United States)

    Leong, Rick C.; Friess, Daniel A.; Crase, Beth; Lee, Wei Kit; Webb, Edward L.

    2018-03-01

    Mangrove vegetation species respond to multiple environmental gradients, and an enhanced understanding of how mangrove species are distributed across these gradients will facilitate conservation and management. Many environmental gradients correlate with tidal inundation; however small-scale inundation patterns resulting from microtopographical changes are difficult to capture empirically. In contrast, surface elevation is often a suitable, measurable and cost-effective proxy for inundation. This study investigated the relationships between species distribution and surface elevation in a mangrove forest in northwest Singapore. Through high-resolution land surveying, we developed a digital elevation model (DEM) and conducted a comprehensive survey of 4380 trees with a stem diameter ≥ 5 cm. A total of 15 species were encountered, and elevation envelopes were generated for 12. Species envelopes were distributed along an elevation continuum, with most species overlapping within the continuum. Spatial autocorrelation (SAC) was present for nine of the 15 species, and when taken into account, species ordering was modified across the elevation continuum. The presence of SAC strongly reinforces the need for research to control for SAC: classical spatial description of mangrove species distribution should be revised to account for ecological factors. This study suggests that (1) surface elevation applies strong controls on species distribution and (2) most mangroves at our study site have similar physiological tolerances.

  3. Modelling Periglacial Processes on Low-Relief High-Elevation Surfaces

    DEFF Research Database (Denmark)

    Andersen, Jane Lund; Knudsen, Mads Faurschou; Egholm, D.L.

    Are low-relief high-elevation surfaces generally a result of uplift of flat surfaces formed close to sea-level or can they be formed "in situ" by climate dependent surface processes such as those associated with glaciation? This question is important to resolve in order to understand the geological...... as a function of mean annual air temperature and sediment thickness. This allows us to incorporate periglacial processes into a long-term landscape evolution model where surface elevation, sediment thickness, and climate evolve over time. With this model we are able to explore the slow feedbacks between...... periglacial erosion, sediment transport, and the evolving topography. We show that smooth peaks, convex hillslopes, and a few meters thick regolith cover at high elevation are emergent properties of the landscape evolution model. By varying climate and other model parameters, we discuss how the landscape...

  4. Evaluation of Airborne Lidar Elevation Surfaces for Propagation of Coastal Inundation: The Importance of Hydrologic Connectivity

    Directory of Open Access Journals (Sweden)

    Sandra Poppenga

    2015-09-01

    Full Text Available Detailed information about coastal inundation is vital to understanding dynamic and populated areas that are impacted by storm surge and flooding. To understand these natural hazard risks, lidar elevation surfaces are frequently used to model inundation in coastal areas. A single-value surface method is sometimes used to inundate areas in lidar elevation surfaces that are below a specified elevation value. However, such an approach does not take into consideration hydrologic connectivity between elevation grids cells resulting in inland areas that should be hydrologically connected to the ocean, but are not. Because inland areas that should drain to the ocean are hydrologically disconnected by raised features in a lidar elevation surface, simply raising the water level to propagate coastal inundation will lead to inundation uncertainties. We took advantage of this problem to identify hydrologically disconnected inland areas to point out that they should be considered for coastal inundation, and that a lidar-based hydrologic surface should be developed with hydrologic connectivity prior to inundation analysis. The process of achieving hydrologic connectivity with hydrologic-enforcement is not new, however, the application of hydrologically-enforced lidar elevation surfaces for improved coastal inundation mapping as approached in this research is innovative. In this article, we propagated a high-resolution lidar elevation surface in coastal Staten Island, New York to demonstrate that inland areas lacking hydrologic connectivity to the ocean could potentially be included in inundation delineations. For inland areas that were hydrologically disconnected, we evaluated if drainage to the ocean was evident, and calculated an area exceeding 11 ha (~0.11 km2 that could be considered in inundation delineations. We also assessed land cover for each inland area to determine the type of physical surfaces that would be potentially impacted if the inland areas

  5. Improving maps of ice-sheet surface elevation change using combined laser altimeter and stereoscopic elevation model data

    DEFF Research Database (Denmark)

    Fredenslund Levinsen, Joanna; Howat, I. M.; Tscherning, C. C.

    2013-01-01

    ) and Kangerdlugssuaq (KL). We find that the main trunks of JI and KL lowered at rates of 30–35 and 7–20ma_1, respectively. The rates decreased inland. The corresponding errors were 0.3–5.2ma_1 for JI and 0.3–5.1ma_1 for KL, with errors increasing proportionally with distance from the altimeter paths....... that surface to extrapolate elevations away from altimeter flight lines. This reduces the DEM registration errors and fills the gap between the altimeter paths. We use data from ICESat and ATM as well as SPOT 5 DEMs from 2007 and 2008 and apply them to the outlet glaciers Jakobshavn Isbræ (JI...

  6. Filling the voids in the SRTM elevation model — A TIN-based delta surface approach

    Science.gov (United States)

    Luedeling, Eike; Siebert, Stefan; Buerkert, Andreas

    The Digital Elevation Model (DEM) derived from NASA's Shuttle Radar Topography Mission is the most accurate near-global elevation model that is publicly available. However, it contains many data voids, mostly in mountainous terrain. This problem is particularly severe in the rugged Oman Mountains. This study presents a method to fill these voids using a fill surface derived from Russian military maps. For this we developed a new method, which is based on Triangular Irregular Networks (TINs). For each void, we extracted points around the edge of the void from the SRTM DEM and the fill surface. TINs were calculated from these points and converted to a base surface for each dataset. The fill base surface was subtracted from the fill surface, and the result added to the SRTM base surface. The fill surface could then seamlessly be merged with the SRTM DEM. For validation, we compared the resulting DEM to the original SRTM surface, to the fill DEM and to a surface calculated by the International Center for Tropical Agriculture (CIAT) from the SRTM data. We calculated the differences between measured GPS positions and the respective surfaces for 187,500 points throughout the mountain range (ΔGPS). Comparison of the means and standard deviations of these values showed that for the void areas, the fill surface was most accurate, with a standard deviation of the ΔGPS from the mean ΔGPS of 69 m, and only little accuracy was lost by merging it to the SRTM surface (standard deviation of 76 m). The CIAT model was much less accurate in these areas (standard deviation of 128 m). The results show that our method is capable of transferring the relative vertical accuracy of a fill surface to the void areas in the SRTM model, without introducing uncertainties about the absolute elevation of the fill surface. It is well suited for datasets with varying altitude biases, which is a common problem of older topographic information.

  7. Groundwater control of mangrove surface elevation: shrink and swell varies with soil depth

    Science.gov (United States)

    Whelan, K.R.T.; Smith, T. J.; Cahoon, D.R.; Lynch, J.C.; Anderson, G.H.

    2005-01-01

    We measured monthly soil surface elevation change and determined its relationship to groundwater changes at a mangrove forest site along Shark River, Everglades National Park, Florida. We combined the use of an original design, surface elevation table with new rod-surface elevation tables to separately track changes in the mid zone (0?4 m), the shallow root zone (0?0.35 m), and the full sediment profile (0?6 m) in response to site hydrology (daily river stage and groundwater piezometric pressure). We calculated expansion and contraction for each of the four constituent soil zones (surface [accretion and erosion; above 0 m], shallow zone [0?0.35 m], middle zone [0.35?4 m], and bottom zone [4?6 m]) that comprise the entire soil column. Changes in groundwater pressure correlated strongly with changes in soil elevation for the entire profile (Adjusted R2 5 0.90); this relationship was not proportional to the depth of the soil profile sampled. The change in thickness of the bottom soil zone accounted for the majority (R2 5 0.63) of the entire soil profile expansion and contraction. The influence of hydrology on specific soil zones and absolute elevation change must be considered when evaluating the effect of disturbances, sea level rise, and water management decisions on coastal wetland systems.

  8. Sea level and turbidity controls on mangrove soil surface elevation change

    Science.gov (United States)

    Lovelock, Catherine E.; Fernanda Adame, Maria; Bennion, Vicki; Hayes, Matthew; Reef, Ruth; Santini, Nadia; Cahoon, Donald R.

    2015-01-01

    Increases in sea level are a threat to seaward fringing mangrove forests if levels of inundation exceed the physiological tolerance of the trees; however, tidal wetlands can keep pace with sea level rise if soil surface elevations can increase at the same pace as sea level rise. Sediment accretion on the soil surface and belowground production of roots are proposed to increase with increasing sea level, enabling intertidal habitats to maintain their position relative to mean sea level, but there are few tests of these predictions in mangrove forests. Here we used variation in sea level and the availability of sediments caused by seasonal and inter-annual variation in the intensity of La Nina-El Nino to assess the effects of increasing sea level on surface elevation gains and contributing processes (accretion on the surface, subsidence and root growth) in mangrove forests. We found that soil surface elevation increased with mean sea level (which varied over 250 mm during the study) and with turbidity at sites where fine sediment in the water column is abundant. In contrast, where sediments were sandy, rates of surface elevation gain were high, but not significantly related to variation in turbidity, and were likely to be influenced by other factors that deliver sand to the mangrove forest. Root growth was not linked to soil surface elevation gains, although it was associated with reduced shallow subsidence, and therefore may contribute to the capacity of mangroves to keep pace with sea level rise. Our results indicate both surface (sedimentation) and subsurface (root growth) processes can influence mangrove capacity to keep pace with sea level rise within the same geographic location, and that current models of tidal marsh responses to sea level rise capture the major feature of the response of mangroves where fine, but not coarse, sediments are abundant.

  9. Sea level and turbidity controls on mangrove soil surface elevation change

    Science.gov (United States)

    Lovelock, Catherine E.; Adame, Maria Fernanda; Bennion, Vicki; Hayes, Matthew; Reef, Ruth; Santini, Nadia; Cahoon, Donald R.

    2015-02-01

    Increases in sea level are a threat to seaward fringing mangrove forests if levels of inundation exceed the physiological tolerance of the trees; however, tidal wetlands can keep pace with sea level rise if soil surface elevations can increase at the same pace as sea level rise. Sediment accretion on the soil surface and belowground production of roots are proposed to increase with increasing sea level, enabling intertidal habitats to maintain their position relative to mean sea level, but there are few tests of these predictions in mangrove forests. Here we used variation in sea level and the availability of sediments caused by seasonal and inter-annual variation in the intensity of La Nina-El Nino to assess the effects of increasing sea level on surface elevation gains and contributing processes (accretion on the surface, subsidence and root growth) in mangrove forests. We found that soil surface elevation increased with mean sea level (which varied over 250 mm during the study) and with turbidity at sites where fine sediment in the water column is abundant. In contrast, where sediments were sandy, rates of surface elevation gain were high, but not significantly related to variation in turbidity, and were likely to be influenced by other factors that deliver sand to the mangrove forest. Root growth was not linked to soil surface elevation gains, although it was associated with reduced shallow subsidence, and therefore may contribute to the capacity of mangroves to keep pace with sea level rise. Our results indicate both surface (sedimentation) and subsurface (root growth) processes can influence mangrove capacity to keep pace with sea level rise within the same geographic location, and that current models of tidal marsh responses to sea level rise capture the major feature of the response of mangroves where fine, but not coarse, sediments are abundant.

  10. Surface elevation changes of the greenland ice sheet - results from ESA'S ice sheet CCI

    DEFF Research Database (Denmark)

    Fredenslund Levinsen, Joanna; Khvorostovky, Kirill; Meister, Rakia

    2013-01-01

    In order to ensure long-term climate data records for the Greenland Ice Sheet (GIS), ESA have launched the Climate Change Initiative (CCI). This work presents the preliminary steps towards the Ice Sheet CCI's surface elevation change (SEC) derivation using radar altimeter data. In order to find...

  11. Leaf size and surface characteristics of Betula papyrifera exposed to elevated CO2 and O3

    Science.gov (United States)

    Johanna Riikonen; Kevin E. Percy; Minna Kivimaenpaa; Mark E. Kubiske; Neil D. Nelson; Elina Vapaavuori; David F. Karnosky

    2010-01-01

    Betula papyrifera trees were exposed to elevated concentrations of CO2 (1.4 x ambient), O3 (1.2 x ambient) or CO2 + O3 at the Aspen Free-air CO2 Enrichment Experiment. The treatment effects on leaf surface characteristics were studied...

  12. Surface elevation changes of the greenland ice sheet - results from ESA'S ice sheet CCI

    DEFF Research Database (Denmark)

    Fredenslund Levinsen, Joanna; Khvorostovky, Kirill; Meister, Rakia

    2013-01-01

    In order to ensure long-term climate data records for the Greenland Ice Sheet (GIS), ESA have launched the Climate Change Initiative (CCI). This work presents the preliminary steps towards the Ice Sheet CCI's surface elevation change (SEC) derivation using radar altimeter data. In order to find t...

  13. Comparison of Surface Flow Features from Lidar-Derived Digital Elevation Models with Historical Elevation and Hydrography Data for Minnehaha County, South Dakota

    Science.gov (United States)

    Poppenga, Sandra K.; Worstell, Bruce B.; Stoker, Jason M.; Greenlee, Susan K.

    2009-01-01

    The U.S. Geological Survey (USGS) has taken the lead in the creation of a valuable remote sensing product by incorporating digital elevation models (DEMs) derived from Light Detection and Ranging (lidar) into the National Elevation Dataset (NED), the elevation layer of 'The National Map'. High-resolution lidar-derived DEMs provide the accuracy needed to systematically quantify and fully integrate surface flow including flow direction, flow accumulation, sinks, slope, and a dense drainage network. In 2008, 1-meter resolution lidar data were acquired in Minnehaha County, South Dakota. The acquisition was a collaborative effort between Minnehaha County, the city of Sioux Falls, and the USGS Earth Resources Observation and Science (EROS) Center. With the newly acquired lidar data, USGS scientists generated high-resolution DEMs and surface flow features. This report compares lidar-derived surface flow features in Minnehaha County to 30- and 10-meter elevation data previously incorporated in the NED and ancillary hydrography datasets. Surface flow features generated from lidar-derived DEMs are consistently integrated with elevation and are important in understanding surface-water movement to better detect surface-water runoff, flood inundation, and erosion. Many topographic and hydrologic applications will benefit from the increased availability of accurate, high-quality, and high-resolution surface-water data. The remotely sensed data provide topographic information and data integration capabilities needed for meeting current and future human and environmental needs.

  14. Decadal changes of surface elevation over permafrost area estimated using reflected GPS signals

    Science.gov (United States)

    Liu, Lin; Larson, Kristine M.

    2018-02-01

    Conventional benchmark-based survey and Global Positioning System (GPS) have been used to measure surface elevation changes over permafrost areas, usually once or a few times a year. Here we use reflected GPS signals to measure temporal changes of ground surface elevation due to dynamics of the active layer and near-surface permafrost. Applying the GPS interferometric reflectometry technique to the multipath signal-to-noise ratio data collected by a continuously operating GPS receiver mounted deep in permafrost in Barrow, Alaska, we can retrieve the vertical distance between the antenna and reflecting surface. Using this unique kind of observables, we obtain daily changes of surface elevation during July and August from 2004 to 2015. Our results show distinct temporal variations at three timescales: regular thaw settlement within each summer, strong interannual variability that is characterized by a sub-decadal subsidence trend followed by a brief uplift trend, and a secular subsidence trend of 0.26 ± 0.02 cm year-1 during 2004 and 2015. This method provides a new way to fully utilize data from continuously operating GPS sites in cold regions for studying dynamics of the frozen ground consistently and sustainably over a long time.

  15. Unusual surface morphology from digital elevation models of the Greenland ice sheet

    DEFF Research Database (Denmark)

    Ekholm, Simon; Keller, K.; Bamber, J.L.

    1998-01-01

    In this study of the North Greenland ice sheet, we have used digital elevation models to investigate the topographic signatures of a large ice flow feature discovered in 1993 and a unique surface anomaly which we believe has not been observed previously. The small scale topography of the flow...... feature is revealed in striking detail in a high-pass filtered elevation model. Furthermore, ice penetrating radar show that the sub-stream bed is rough with undulation amplitude increasing downstream. The new feature consists of two large depressions in the ice sheet connected by a long curving trench...

  16. Elevation change of the Greenland Ice Sheet due to surface mass balance and firn processes, 1960-2014

    NARCIS (Netherlands)

    Kuipers Munneke, P.; Ligtenberg, S. R M; Noël, B. P Y; Howat, I. M.; Box, J. E.; Mosley-Thompson, E.; McConnell, J. R.; Steffen, K.; Harper, J. T.; Das, S. B.; Van Den Broeke, M. R.

    2015-01-01

    Observed changes in the surface elevation of the Greenland Ice Sheet are caused by ice dynamics, basal elevation change, basal melt, surface mass balance (SMB) variability, and by compaction of the overlying firn. The last two contributions are quantified here using a firn model that includes

  17. Use of remotely sensed land surface temperature as a proxy for air temperatures at high elevations: Findings from a 5000 m elevational transect across Kilimanjaro

    Science.gov (United States)

    Pepin, N. C.; Maeda, E. E.; Williams, R.

    2016-09-01

    High elevations are thought to be warming more rapidly than lower elevations, but there is a lack of air temperature observations in high mountains. This study compares instantaneous values of land surface temperature (10:30/22:30 and 01:30/13:30 local solar time) as measured by Moderate Resolution Imaging Spectroradiometer MOD11A2/MYD11A2 at 1 km resolution from the Terra and Aqua platforms, respectively, with equivalent screen-level air temperatures (in the same pixel). We use a transect of 22 in situ weather stations across Kilimanjaro ranging in elevation from 990 to 5803 m, one of the biggest elevational ranges in the world. There are substantial differences between LST and Tair, sometimes up to 20°C. During the day/night land surface temperature tends to be higher/lower than Tair. LST-Tair differences (ΔT) show large variance, particularly during the daytime, and tend to increase with elevation, particularly on the NE slope which faces the morning Sun. Differences are larger in the dry seasons (JF and JJAS) and reduce in cloudy seasons. Healthier vegetation (as measured by normalized difference vegetation index) and increased humidity lead to reduced daytime surface heating above air temperature and lower ΔT, but these relationships weaken with elevation. At high elevations transient snow cover cools LST more than Tair. The predictability of ΔT therefore reduces. It will therefore be challenging to use satellite data at high elevations as a proxy for in situ air temperatures in climate change assessments, especially for daytime Tmax. ΔT is smaller and more consistent at night, so it will be easier to use LST to monitor changes in Tmin.

  18. Where’s the Ground Surface? – Elevation Bias in LIDAR-derived Digital Elevation Models Due to Dense Vegetation in Oregon Tidal Marshes

    Science.gov (United States)

    Light Detection and Ranging (LIDAR) is a powerful resource for coastal and wetland managers and its use is increasing. Vegetation density and other land cover characteristics influence the accuracy of LIDAR-derived ground surface digital elevation models; however the degree to wh...

  19. The influence of changes in glacier extent and surface elevation on modeled mass balance

    Directory of Open Access Journals (Sweden)

    F. Paul

    2010-12-01

    Full Text Available Glaciers are widely recognized as unique demonstration objects for climate change impacts, mostly due to the strong change of glacier length in response to small climatic changes. However, glacier mass balance as the direct response to the annual atmospheric conditions can be better interpreted in meteorological terms. When the climatic signal is deduced from long-term mass balance data, changes in glacier geometry (i.e. surface extent and elevation must be considered as such adjustments form an essential part of the glacier reaction to new climatic conditions. In this study, a set of modelling experiments is performed to assess the influence of changes in glacier geometry on mass balance for constant climatic conditions. The calculations are based on a simplified distributed energy/mass balance model in combination with information on glacier extent and surface elevation for the years 1850 and 1973/1985 for about 60 glaciers in the Swiss Alps. The results reveal that over this period about 50–70% of the glacier reaction to climate change (here a one degree increase in temperature is "hidden" in the geometric adjustment, while only 30–50% can be measured as the long-term mean mass balance. For larger glaciers, the effect of the areal change is partly reduced by a lowered surface elevation, which results in a slightly more negative balance despite a potential increase of topographic shading. In view of several additional reinforcement feedbacks that are observed in periods of strong glacier decline, it seems that the climatic interpretation of long-term mass balance data is rather complex.

  20. SWOT: The Surface Water and Ocean Topography Mission. Wide- Swath Altimetric Elevation on Earth

    Science.gov (United States)

    Fu, Lee-Lueng (Editor); Alsdorf, Douglas (Editor); Morrow, Rosemary; Rodriguez, Ernesto; Mognard, Nelly

    2012-01-01

    The elevation of the surface of the ocean and freshwater bodies on land holds key information on many important processes of the Earth System. The elevation of the ocean surface, called ocean surface topography, has been measured by conventional nadirlooking radar altimeter for the past two decades. The data collected have been used for the study of large-scale circulation and sea level change. However, the spatial resolution of the observations has limited the study to scales larger than about 200 km, leaving the smaller scales containing substantial kinetic energy of ocean circulation that is responsible for the flux of heat, dissolved gas and nutrients between the upper and the deep ocean. This flux is important to the understanding of the ocean's role in regulatingfuture climate change.The elevation of the water bodies on land is a key parameter required for the computation of storage and discharge of freshwater in rivers, lakes, and wetlands. Globally, the spatial and temporal variability of water storage and discharge is poorly known due to the lack of well-sampled observations. In situ networks measuring river flows are declining worldwide due to economic and political reasons. Conventional altimeter observations suffers from the complexity of multiple peaks caused by the reflections from water, vegetation canopy and rough topography, resulting in much less valid data over land than over the ocean. Another major limitation is the large inter track distance preventing good coverage of rivers and other water bodies.This document provides descriptions of a new measurement technique using radar interferometry to obtain wide-swath measurement of water elevation at high resolution over both the ocean and land. Making this type of measurement, which addresses the shortcomings of conventional altimetry in both oceanographic and hydrologic applications, is the objective of a mission concept called Surface Water and Ocean Topography (SWOT), which was recommended by

  1. The two-thumb technique using an elevated surface is preferable for teaching infant cardiopulmonary resuscitation.

    Science.gov (United States)

    Huynh, Trang K; Hemway, Rae Jean; Perlman, Jeffrey M

    2012-10-01

    To determine whether the two-thumb technique is superior to the two-finger technique for administering chest compressions using the floor surface and the preferred location for performing infant cardiopulmonary resuscitation (CPR) (ie, floor, table, or radiant warmer). Twenty Neonatal Resuscitation Program trained medical personnel performed CPR on a neonatal manikin utilizing the two-thumb vs two-finger technique, a compression to ventilation ratio of 30:2 for 2 minutes in random order on the floor, table, and radiant warmer. Compression depth favored the two-thumb over two-finger technique on the floor (27 ± 8 mm vs 23 ± 7), table (26 ± 7 mm vs 22 ± 7), and radiant warmer (29 ± 4 mm vs 23 ± 4) (all P CPR preferably using an elevated firm surface. Copyright © 2012 Mosby, Inc. All rights reserved.

  2. Improving surface stability of elevated spoil landforms using natural landform analogy and geological information

    Science.gov (United States)

    Emmerton, Bevan; Burgess, Jon; Esterle, Joan; Erskine, Peter; Baumgartl, Thomas

    2017-04-01

    Large-scale open cut mining in the Bowen Basin, Queensland, Australia has undergone an evolutionary process over the period of a few decades, transitioning from shallow mining depths, limited spoil elevation and pasture based rehabilitation to increased mining depths, escalating pre-stripping, elevated mesa-like landforms and native woody species rehabilitation. As a consequence of this development, the stabilisation of recent constructed landforms has to be assured through means other than the establishment of vegetative cover. Recent developments are the specific selection and partitioning of resilient fragmental spoil types for the construction of final landform surface. They can also be used as cladding resources for stabilizing steep erosive batters and this has been identified as a practical methodology that has the potential to significantly improve rehabilitation outcomes. Examples of improvements are an increase of the surface rock cover, roughness and infiltration and reducing inherent erodibility and runoff and velocity of surface flow. However, a thorough understanding of the properties and behavior of individual spoil materials disturbed during mining is required. Relevant information from published literature on the geological origins, lithology and weathering characteristics of individual strata within the Bowen Basin Coal Measures located in Queensland, Australia (and younger overlying weathered strata) has been studied, and related both to natural landforms and to the surface stability of major strata types when disturbed by mining. The resulting spoil classification developed from this study is based primarily on inherent geological characteristics and weathering behaviour of identifiable lithologic components, and as such describes the expected fragmental resilience likely within disturbed materials at Bowen Basin coal mines. The proposed classification system allows the allocation of spoil types to use categories which have application in pre

  3. Water surface elevation from the upcoming SWOT mission under different flows conditions

    Science.gov (United States)

    Domeneghetti, Alessio; Schumann, Guy J. P.; Wei, Rui; Frasson, Renato P. M.; Durand, Michael; Pavelsky, Tamlin; Castellarin, Attilio; Brath, Armando

    2017-04-01

    The upcoming SWOT (Surface Water and Ocean Topography) satellite mission will provide unprecedented bi-dimensional observations of terrestrial water surface heights along rivers wider than 100m. Despite the literature reports several activities showing possible uses of SWOT products, potential and limitations of satellite observations still remain poorly understood and investigated. We present one of the first analyses regarding the spatial observation of water surface elevation expected from SWOT for a 140 km reach of the middle-lower portion of the Po River, in Northern Italy. The river stretch is characterized by a main channel varying from 100-500 m in width and a floodplain delimited by a system of major embankments that can be as wide as 5 km. The reconstruction of the hydraulic behavior of the Po River is performed by means of a quasi-2D model built with detailed topographic and bathymetric information (LiDAR, 2m resolution), while the simulation of remotely sensed hydrometric data is performed with a SWOT simulator that mimics the satellite sensor characteristics. Referring to water surface elevations associated with different flow conditions (maximum, minimum and average flow) this work characterizes the spatial observations provided by SWOT and highlights the strengths and limitations of the expected products. The analysis provides a robust reference for spatial water observations that will be available from SWOT and assesses possible effects of river embankments, river width and river topography under different hydraulic conditions. Results of the study characterize the expected accuracy of the upcoming SWOT mission and provide additional insights towards the appropriate exploitation of future hydrological observations.

  4. Surface anatomy of the lip elevator muscles for the treatment of gummy smile using botulinum toxin.

    Science.gov (United States)

    Hwang, Woo-Sang; Hur, Mi-Sun; Hu, Kyung-Seok; Song, Wu-Chul; Koh, Ki-Seok; Baik, Hyoung-Seon; Kim, Seong-Taek; Kim, Hee-Jin; Lee, Kee-Joon

    2009-01-01

    To propose a safe and reproducible injection point for botulinum toxin-A (BTX-A) as a supplementary method for the treatment of gummy smile, as determined by assessment of the morphologic characteristics of three lip elevator muscles. A total of 50 hemi-faces from 25 adult cadavers (male 13, female 12; ages, 47 to 88 years) were used in this study. Topographic relations and the directions of the lip elevator muscles (ie, levator labii superioris [LLS], levator labii superioris alaeque nasi [LLSAN], and zygomaticus minor [ZMi]), were investigated. Possible injection points were examined through the study of predetermined surface landmarks. The insertion of the LLS was covered partially or entirely by the LLSAN and the ZMi, and the three muscles converged on the area lateral to the ala. The mean angle between the facial midline and each muscle vector was 25.8 +/- 4.8 degrees for the LLS, 55.7 +/- 6.4 degrees for the ZMi, and -20.2 +/- 3.2 degrees for the LLSAN; no significant differences were noted between male and female subjects or between left and right sides. The three vectors passed near a triangular region formed by three surface landmarks. The center of this triangle, named the "Yonsei point", was suggested as an appropriate injection point for BTX-A. The clinical effectiveness of the injection point was demonstrated in selected cases with or without orthodontic treatment. Under careful case selection, BTX-A may be an effective treatment alternative for patients with excessive gingival display caused by hyperactive lip elevator muscles.

  5. Impact of the surface characteristics on the quality of INSAR elevation data

    Science.gov (United States)

    Heidelmeyer, G.; Klingauf, U.

    2006-09-01

    Due to upcoming new data driven technologies in the aviation the impact of digital terrain data is growing conspicuously. Especially for ground near operations reliable terrain information is necessarily demanded. Based on modern earth observation technologies a new generation of elevation data is obtainable. However it shall be analysed how far data derived from remote sensing techniques like INSAR or LIDAR can be applied for aviation purposes. Formerly terrain data were represented in relation to the bare earth to obtain a "Digital Terrain Model" (DTM). For aviation purposes a "Digital Surface Model" (DSM) representing the real surface of the earth including all cover like vegetation and buildings is recommended. Due to the characteristics of active remote sensors the derived model always describes an in between of the two elevation representations. To satisfy the special requirements the Institute of Flight Systems and Automatic Control (FSR) at the Technische Universitaet Darmstadt is dealing with the determination of the influencing factors which affect the quality of the terrain models being appropriate to be used as a DSM. In order to enhance the integrity of the data a "safety buffer" is created to allow the applicability for dedicated applications (figure 1).

  6. Development of a GNSS Buoy for Monitoring Water Surface Elevations in Estuaries and Coastal Areas.

    Science.gov (United States)

    Lin, Yen-Pin; Huang, Ching-Jer; Chen, Sheng-Hsueh; Doong, Dong-Jiing; Kao, Chia Chuen

    2017-01-18

    In this work, a Global Navigation Satellite System (GNSS) buoy that utilizes a Virtual Base Station (VBS) combined with the Real-Time Kinematic (RTK) positioning technology was developed to monitor water surface elevations in estuaries and coastal areas. The GNSS buoy includes a buoy hull, a RTK GNSS receiver, data-transmission devices, a data logger, and General Purpose Radio Service (GPRS) modems for transmitting data to the desired land locations. Laboratory and field tests were conducted to test the capability of the buoy and verify the accuracy of the monitored water surface elevations. For the field tests, the GNSS buoy was deployed in the waters of Suao (northeastern part of Taiwan). Tide data obtained from the GNSS buoy were consistent with those obtained from the neighboring tide station. Significant wave heights, zero-crossing periods, and peak wave directions obtained from the GNSS buoy were generally consistent with those obtained from an accelerometer-tilt-compass (ATC) sensor. The field tests demonstrate that the developed GNSS buoy can be used to obtain accurate real-time tide and wave data in estuaries and coastal areas.

  7. Electrochemical removal of segregated silicon dioxide impurities from yttria stabilized zirconia surfaces at elevated temperatures

    DEFF Research Database (Denmark)

    Andersen, Thomas; Hansen, Karin Vels; Mogensen, Mogens Bjerg

    2011-01-01

    Here we report on the electrochemical removal of segregated silicon dioxide impurities from Yttria Stabilized Zirconia (YSZ) surfaces at elevated temperatures studied under Ultra High Vacuum (UHV) conditions. YSZ single crystals were heated in vacuum by an applied 18kHz a.c. voltage using the ion....... This was demonstrated by silicon enrichment of a gold foil placed behind the YSZ crystal surface while annealed. The results suggest a fast way to clean YSZ for trace silicon dioxide impurities found in the bulk of the cleanest crystals commercially available....... conductivity of YSZ. The crystals were annealed in vacuum and atmospheres of water or oxygen from 10−5 mbar to 100mbar in the temperature range of 1100°C to 1275°C. The surface was after annealing analyzed by X-ray Photoelectron Spectroscopy (XPS) without exposing the crystal to atmosphere between annealing...... and XPS analysis. Silicon enrichment of the surface was only observed at oxygen and water vapor partial pressures above 25mbar and 10mbar, respectively. No silicon was observed on crystals annealed in vacuum and at oxygen and water vapor partial pressures below 10mbar. The YSZ seems to get partially...

  8. AirSWOT Measurements of Water Surface Elevations and Hydraulic Gradients over the Yukon Flats, Alaska

    Science.gov (United States)

    Pitcher, L. H.; Pavelsky, T.; Smith, L. C.; Moller, D.; Altenau, E. H.; Lion, C.; Bertram, M.; Cooley, S. W.

    2017-12-01

    AirSWOT is an airborne, Ka-band synthetic aperture radar interferometer (InSAR) intended to quantify surface water fluxes by mapping water surface elevations (WSE). AirSWOT will also serve as a calibration/validation tool for the Surface Water and Ocean Topography (SWOT) satellite mission (scheduled for launch in 2021). The hydrology objectives for AirSWOT and SWOT are to measure WSE with accuracies sufficient to estimate hydrologic fluxes in lakes, wetlands and rivers. However, current understanding of the performance of these related though not identical instruments when applied to complex river-lake-wetland fluvial environments remains predominantly theoretical. We present AirSWOT data acquired 15-June-2015 over the Yukon Flats, Alaska, USA, together with in situ field surveys, to assess the accuracy of AirSWOT WSE measurements in lakes and rivers. We use these data to demonstrate that AirSWOT can be used to estimate large-scale hydraulic gradients across wetland complexes. Finally, we present key lessons learned from this AirSWOT analysis for consideration in future campaigns, including: maximizing swath overlap for spatial averaging to minimize uncertainty as well as orienting flight paths parallel to river flow directions to reduce along track aircraft drift for neighboring flight paths. We conclude that spatially dense AirSWOT measurements of river and lake WSEs can improve geospatial understanding of surface water hydrology and fluvial processes.

  9. Flood Damage Analysis: First Floor Elevation Uncertainty Resulting from LiDAR-Derived Digital Surface Models

    Directory of Open Access Journals (Sweden)

    José María Bodoque

    2016-07-01

    Full Text Available The use of high resolution ground-based light detection and ranging (LiDAR datasets provides spatial density and vertical precision for obtaining highly accurate Digital Surface Models (DSMs. As a result, the reliability of flood damage analysis has improved significantly, owing to the increased accuracy of hydrodynamic models. In addition, considerable error reduction has been achieved in the estimation of first floor elevation, which is a critical parameter for determining structural and content damages in buildings. However, as with any discrete measurement technique, LiDAR data contain object space ambiguities, especially in urban areas where the presence of buildings and the floodplain gives rise to a highly complex landscape that is largely corrected by using ancillary information based on the addition of breaklines to a triangulated irregular network (TIN. The present study provides a methodological approach for assessing uncertainty regarding first floor elevation. This is based on: (i generation an urban TIN from LiDAR data with a density of 0.5 points·m−2, complemented with the river bathymetry obtained from a field survey with a density of 0.3 points·m−2. The TIN was subsequently improved by adding breaklines and was finally transformed to a raster with a spatial resolution of 2 m; (ii implementation of a two-dimensional (2D hydrodynamic model based on the 500-year flood return period. The high resolution DSM obtained in the previous step, facilitated addressing the modelling, since it represented suitable urban features influencing hydraulics (e.g., streets and buildings; and (iii determination of first floor elevation uncertainty within the 500-year flood zone by performing Monte Carlo simulations based on geostatistics and 1997 control elevation points in order to assess error. Deviations in first floor elevation (average: 0.56 m and standard deviation: 0.33 m show that this parameter has to be neatly characterized in order

  10. Reconstructing surface elevation changes for the Greenland Ice Sheet (1993-2013) and analysis of Zachariae Isstrom, northeast Greenland

    Science.gov (United States)

    Duncan, Kyle

    Previous studies investigating the velocity and elevation change records of the Greenland Ice Sheet (GrIS) revealed rapid and complex changes. It is therefore imperative to determine changes with both high spatial and temporal resolutions. By fusing multiple laser altimetry data sets, the Surface Elevation Reconstruction and Change (SERAC) program is capable of reconstructing surface elevation changes with high spatial and temporal resolution over the entire GrIS. The input data include observations from NASA's Ice, Cloud and land Elevation Satellite (ICESat) mission (2003-2009) as well as data collected by NASA's Airborne Topographic Mapper (ATM) (1993-2013) and Land, Vegetation and Ice Sensor (LVIS) (2007-2012) airborne laser altimetry systems. This study extends the record of surface elevation changes over the GrIS by adding 2012 and 2013 laser altimetry data to the previous 1993-2011 record. Extending the record leads to a new, more accurate and detailed altimetry record for 1993-2013. Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Digital Elevation Models (DEMs) are fused with laser altimetry data over Zachariae Isstrom, northeast Greenland to analyze surface elevation changes and associated thinning rates during 1978-2014. Little to no elevation change occurred over Zachariae Isstrom from 1978-1999, however, from 1999-2014 elevation changes near the calving front became increasingly negative and accelerated. Calving front position showed steady retreat and grounding line position has been retreating towards the interior of the ice sheet at an increasing rate from 2010-2014 when compared to the 1996-2010 period. The measured elevation changes near the calving front have brought a large portion of the glacier close to the height of flotation. If the current thinning trend continues this portion of the glacier will reach flotation within the next 2-5 years allowing for further retreat and increased vulnerability to retreat for sections of

  11. The impact of elevated CO2 on the energy and water balance over terrestrial surfaces

    Science.gov (United States)

    Roderick, Michael; Donohue, Randall; Yang, Yuting; McVicar, Tim

    2017-04-01

    When we think of the enhanced greenhouse effect, the tendency is to focus on the effects on near-surface air temperature and the consequence impacts. On that approach the underlying cause of the enhanced greenhouse effect, that is, increasing atmospheric CO2 tends to be ignored. But laboratory experiments have long shown that increasing CO2 has a large impact on vegetation gas exchange, by, for example, increasing water use efficiency of photosynthesis. This tends to be a forgotten factor in the meteorological and hydrologic sciences. In this talk we outline some key expected effects of atmospheric CO2 on leaf-, canopy- and catchment-scale fluxes and compare those expectations with both site- (e.g. FACE) and catchment-scale observations. We find the expected effects have been observed over undisturbed vegetation. However, we find the effects of elevated CO2 are more complex in disturbed vegetation that is actively regrowing, This finding suggests the disturbance history will be a key factor on the canopy- and catchment-scale responses to elevated CO2.

  12. A Global Map of Coherent M2 Internal Tide Surface Elevations

    Science.gov (United States)

    Ray, R. D.; Zaron, E. D.

    2014-12-01

    Satellite altimetry reveals small surface waves, with elevations of order 1 cm or smaller, associated with internal tides in the deep ocean. The global satellite data provide an unprecedented picture of such waves, potentially yielding much information about the ocean interior. Accurate knowledge of these waves is also needed for de-tiding altimetry in certain sensitive applications, including the future SWOT mission. Several approaches have been initiated recently to map these tiny waves, usually with some reliance on hydrographic information (e.g., recent work by Dushaw et al., 2011). Here we explore the feasibility of a purely empirical approach which avoids assumptions about stratification or modal wavelengths. A global elevation map is constructed based on tidal analysis of Topex/Poseidon, Jason, ERS-2, Envisat and GFO data. Small (order 5 mm) residuals, with wavelengths much longer than the baroclinic tide, appear unless now-standard along-track high-pass filters are applied, but filtering is shown to cause serious loss of information for east-west propagating waves (given typical track patterns). The technique is probably infeasible for S2 because of Envisat's and ERS's sun-synchronous orbits. Independent data from Cryosat-2 is used to validate the results. Applying our internal-tide 'correction' to Cryosat-2 data confirms a small reduction in variance in expected locations of significant internal tides.

  13. Estimating Discharge, Depth and Bottom Friction in Sand Bed Rivers Using Surface Currents and Water Surface Elevation Observations

    Science.gov (United States)

    Simeonov, J.; Czapiga, M. J.; Holland, K. T.

    2017-12-01

    We developed an inversion model for river bathymetry estimation using measurements of surface currents, water surface elevation slope and shoreline position. The inversion scheme is based on explicit velocity-depth and velocity-slope relationships derived from the along-channel momentum balance and mass conservation. The velocity-depth relationship requires the discharge value to quantitatively relate the depth to the measured velocity field. The ratio of the discharge and the bottom friction enter as a coefficient in the velocity-slope relationship and is determined by minimizing the difference between the predicted and the measured streamwise variation of the total head. Completing the inversion requires an estimate of the bulk friction, which in the case of sand bed rivers is a strong function of the size of dune bedforms. We explored the accuracy of existing and new empirical closures that relate the bulk roughness to parameters such as the median grain size diameter, ratio of shear velocity to sediment fall velocity or the Froude number. For given roughness parameterization, the inversion solution is determined iteratively since the hydraulic roughness depends on the unknown depth. We first test the new hydraulic roughness parameterization using estimates of the Manning roughness in sand bed rivers based on field measurements. The coupled inversion and roughness model is then tested using in situ and remote sensing measurements of the Kootenai River east of Bonners Ferry, ID.

  14. Full 2D observation of water surface elevation from SWOT under different flow conditions

    Science.gov (United States)

    Domeneghetti, Alessio; Schumann, Guy; Rui, Wei; Durand, Michael; Pavelsky, Tamlin

    2016-04-01

    The upcoming Surface Water and Ocean Topography (SWOT) satellite mission is a joint project of NASA, Centre National d'Etudes Spatiales (CNES, France), the Canadian Space Agency, and the Space Agency of the UK that will provide a first global, high-resolution observation of ocean and terrestrial water surface heights. Characterized by an observation swath of 120 km and an orbit repeat interval of about 21 days, SWOT will provide unprecedented bi-dimensional observations of rivers wider than 50-100 m. Despite many research activities that have investigated potential uses of remotely sensed data from SWOT, potentials and limitations of the spatial observations provided by the satellite mission for flood modeling still remain poorly understood and investigated. In this study we present a first analysis of the spatial observation of water surface elevation that is expected from SWOT for a 140 km reach of the middle-lower portion of the Po River, in Northern Italy. The river stretch is characterized by a main channel varying from 200-500 m in width and a floodplain that can be as wide as 5 km and that is delimited by a system of major embankments. The reconstruction of the hydraulic behavior of the Po River is performed by means of a quasi-2d model built with detailed topographic and bathymetric information (LiDAR, 2 m resolution), while the simulation of the spatial observation sensed by SWOT is performed with a SWOT simulator that mimics the satellite sensor characteristics. Referring to water surface elevations associated with different flow conditions (maximum, minimum and average flow reproduced by means of the quasi-2d numerical model) this work provides a first characterization of the spatial observations provided by SWOT and highlights the strengths and limitations of the expected products. By referring to a real river reach the analysis provides a credible example of the type of spatial observations that will be available after launch of SWOT and offers a first

  15. Preliminary results of the ice_sheet_CCI round robin activity on the estimation of surface elevation changes

    DEFF Research Database (Denmark)

    Ticconi, F.; Fredenslund Levinsen, Joanna; Khvorostovsky, K.

    2013-01-01

    This work presents the first results of a research activity aiming to compare estimates of Surface Elevation Changes (SEC) over the Jakobshavn Isbræ basin (Greenland) using different repeat altimetry techniques and different sensors (laser vs. radar altimetry). The goal of this comparison...... is the identification of the best performing algorithm, in terms of accuracy, coverage and processing effort, for the generation of surface elevation change maps. The methods investigated here are the cross-over and repeat-track. The results of the inter-comparison are here reported and, from a first analysis......, it is found that both radar and laser altimetry resolve the surface elevation changes quite well, and that the problems found mainly in the coastal region and along the main trunk can be solved by combining the two methods. The comparison with airborne lidar data from the NASA ICEBridge and the ESA Cryo...

  16. Analysis of overdeepened valleys using the digital elevation model of the bedrock surface of Northern Switzerland

    Energy Technology Data Exchange (ETDEWEB)

    Jordan, P.

    2010-11-15

    Based on surface and borehole information, together with pre-existing regional and local interpretations, a 7,150 square kilometre Raster Digital Elevation Model (DEM) of the bedrock surface of northern Switzerland was constructed using a 25 m cell size. This model represents a further important step in the understanding of Quaternary sediment distribution and is open to a broad field of application and analysis, including hydrogeological, geotechnical and geophysical studies as well as research in the field of Pleistocene landscape evolution. An analysis of the overdeepened valleys in the whole model area and, more specifically in the Reuss area, shows that, in most cases, overdeepening is restricted to the areas covered by the Last Glaciation Maximum (LGM). However, at various locations relatively narrow overdeepened valleys outreach the tongue basins and the LGM ice shield limits. Therefore, an earlier and further-reaching glacial event has probably contributed significantly to the overdeepening of these valleys. No significant overdeepening has been identified downstream of Boettstein (Aare) and Kaiserstuhl (Rhine), although the ice extended considerably further downstream, at least during the most extensive glaciation. Except for the bedrock between Brugg and Boettstein, no overdeepened valleys are found significantly north of the outcrop of Mesozoic limestone of the Folded and Tabular Jura. A detailed analysis of the Reuss area shows that the Lake and Suhre valleys are separated from the Emmen-Gisikon Reuss valley basin by a significant bedrock barrier. The individual bedrock valleys are divided into several sub-basins, indicating a multiphase evolution of the valleys. Some of the swells or barriers separating the sub-basins coincide with known late LGM retreat stages. In the Suhre valley, an old fluvial valley floor with restricted overdeepened sections is documented. (author)

  17. On Monin–Obukhov Scaling in and Above the Atmospheric Surface Layer: The Complexities of Elevated Scintillometer Measurements

    NARCIS (Netherlands)

    Braam, M.; Bosveld, F.C.; Moene, A.F.

    2012-01-01

    In scintillometry Monin–Obukhov similarity theory (MOST) is used to calculate the surface sensible heat flux from the structure parameter of temperature (CT2)(CT2) . In order to prevent saturation a scintillometer can be installed at an elevated level. However, in that case the observation level

  18. Surface elevation change and susceptibility of different mangrove zones to sea-level rise on Pacific high islands of Micronesia

    Science.gov (United States)

    Krauss, K.W.; Cahoon, D.R.; Allen, J.A.; Ewel, K.C.; Lynch, J.C.; Cormier, N.

    2010-01-01

    Mangroves on Pacific high islands offer a number of important ecosystem services to both natural ecological communities and human societies. High islands are subjected to constant erosion over geologic time, which establishes an important source of terrigeneous sediment for nearby marine communities. Many of these sediments are deposited in mangrove forests and offer mangroves a potentially important means for adjusting surface elevation with rising sea level. In this study, we investigated sedimentation and elevation dynamics of mangrove forests in three hydrogeomorphic settings on the islands of Kosrae and Pohnpei, Federated States of Micronesia (FSM). Surface accretion rates ranged from 2.9 to 20.8 mm y-1, and are high for naturally occurring mangroves. Although mangrove forests in Micronesian high islands appear to have a strong capacity to offset elevation losses by way of sedimentation, elevation change over 61/2 years ranged from -3.2 to 4.1 mm y-1, depending on the location. Mangrove surface elevation change also varied by hydrogeomorphic setting and river, and suggested differential, and not uniformly bleak, susceptibilities among Pacific high island mangroves to sea-level rise. Fringe, riverine, and interior settings registered elevation changes of -1.30, 0.46, and 1.56 mm y-1, respectively, with the greatest elevation deficit (-3.2 mm y-1) from a fringe zone on Pohnpei and the highest rate of elevation gain (4.1 mm y-1) from an interior zone on Kosrae. Relative to sea-level rise estimates for FSM (0.8-1.8 mm y-1) and assuming a consistent linear trend in these estimates, soil elevations in mangroves on Kosrae and Pohnpei are experiencing between an annual deficit of 4.95 mm and an annual surplus of 3.28 mm. Although natural disturbances are important in mediating elevation gain in some situations, constant allochthonous sediment deposition probably matters most on these Pacific high islands, and is especially helpful in certain hydrogeomorphic zones

  19. Structure-from-Motion Using Historical Aerial Images to Analyse Changes in Glacier Surface Elevation

    Directory of Open Access Journals (Sweden)

    Nico Mölg

    2017-10-01

    Full Text Available The application of structure-from-motion (SfM to generate digital terrain models (DTMs derived from different image sources has strongly increased, the major reason for this being that processing is substantially easier with SfM than with conventional photogrammetry. To test the functionality in a demanding environment, we applied SfM and conventional photogrammetry to archival aerial images from Zmuttgletscher, a mountain glacier in Switzerland, for nine dates between 1946 and 2005 using the most popular software packages, and compared the results regarding bundle adjustment and final DTM quality. The results suggest that by using SfM it is possible to produce DTMs of similar quality as with conventional photogrammetry. Higher point cloud density and less noise allow a higher ground resolution of the final DTM, and the time effort from the user is 3–6 times smaller, while the controls of the commercial software packages Agisoft PhotoScan (Version 1.2; Agisoft, St. Petersburg, Russia and Pix4Dmapper (Version 3.0; Pix4D, Lausanne, Switzerland are limited in comparison to ERDAS photogrammetry. SfM performs less reliably when few images with little overlap are processed. Even though SfM facilitates the largely automated production of high quality DTMs, the user is not exempt from a thorough quality check, at best with reference data where available. The resulting DTM time series revealed an average change in surface elevation at the glacier tongue of −67.0 ± 5.3 m. The spatial pattern of changes over time reflects the influence of flow dynamics and the melt of clean ice and that under debris cover. With continued technological advances, we expect to see an increasing use of SfM in glaciology for a variety of purposes, also in processing archival aerial imagery.

  20. Surface Elevation Change of Transantarctic Outlet Glaciers using Historical Aerial Imagery and Structure-from-Motion Photogrammetry

    Science.gov (United States)

    Child, S. F.; Stearns, L. A.; Girod, L.

    2017-12-01

    Transantarctic Mountain outlet glaciers drain ice from the East Antarctic Ice Sheet to the Ross Ice Shelf and are generally considered to be stable. However, studies that assess these glaciers typically use data with coarse spatial resolutions (1 - 20 km) and span only the last 15 - 20 years. Here, we use trimetrogon aerial (TMA) photographs collected by the United States Geological Survey from 1960 - 1965 to create historical surface elevation maps. We construct elevations from both the vertical (0° nadir) and oblique photographs using MicMac, a Structure-from-Motion (SfM) software. With typical SfM processing, accurate ground control points (GCPs) are necessary for the best results; however, in situ GCPs are extremely sparse in Antarctica, so we manually identify GCPs using exposed rock outcrops in the WorldView imagery. The historical glacier surface elevations are then compared with present-day elevations derived from WorldView imagery. With this methodology, we assess how Transantarctic outlet glaciers have changed over 55 years. Recent studies indicate thinning of the eastern Ross Ice Shelf, where it borders the Transantarctic Mountains. With long-term records of glacier elevation change, we can differentiate whether ice shelf thinning is driven by changes in glacier or ocean dynamics. These results give us a better understanding of the long-term stability of East Antarctic outlet glaciers, which is essential in improving predictive models of ice sheet behavior.

  1. A surface elevation changes of the Greenland ice sheet from SARAL/AltiKa satellite radar altimeter

    DEFF Research Database (Denmark)

    Khvorostovsky, Kirill; Simonsen, Sebastian Bjerregaard

    Radar altimeter measurements from ERS, Envisat and Cryosat-2 ESA’s satellites have been used for study of the ice sheet elevation changes for more than two decades. The follow-on SARAL ISRO/CNES mission with the radar altimeter AltiKa on board was launched in February 2013 on the same orbit...... as Envisat. However, in contrast to the previous Ku-band radar altimeters, AltiKa operates in Ka-band (36.8 GHz) resulting in smaller footprint, better vertical resolution and decreased penetration of the signal in the snowpack. This work presents Greenland ice sheet surface elevation changes (SEC) derived...... from the first years of SARAL/AltiKa operation as part of the ESA’s Climate Change Initiative program, which addresses the GrIS as one of the Essential Climate Variables. Seasonal changes in elevation and radar altimeter waveform parameters are estimated using crossover and stacking methods...

  2. The microstructure and surface hardness of Ti6Al4V alloy implanted with nitrogen ions at an elevated temperature

    Energy Technology Data Exchange (ETDEWEB)

    Vlcak, Petr, E-mail: petr.vlcak@fs.cvut.cz [Department of Physics, Faculty of Mechanical Engineering, Czech Technical University in Prague, Technicka 4, 16607 Prague (Czech Republic); Cerny, Frantisek [Department of Physics, Faculty of Mechanical Engineering, Czech Technical University in Prague, Technicka 4, 16607 Prague (Czech Republic); Drahokoupil, Jan [Department of Metals, Institute of Physics, AS CR, v.v.i., Na Slovance 2, 182 21 Prague (Czech Republic); Sepitka, Josef [Department of Mechanics, Biomechanics and Mechatronics, Faculty of Mechanical Engineering, Czech Technical University in Prague, Technicka 4, 16607 Prague (Czech Republic); Tolde, Zdenek [Department of Materials Engineering, Faculty of Mechanical Engineering, Czech Technical University in Prague, Technicka 4, 16607 Prague (Czech Republic)

    2015-01-25

    Highlights: • The Ti6Al4V samples were implanted with 90 keV nitrogen ions. • The samples were annealed at 500 °C during the ion implantation process. • An elevated temperature increases the mobility of the atoms and the quantity of TiN. • The hardness showed a significant increase compared to room temperature implantation. - Abstract: The effect of an elevated temperature during nitrogen ion implantation on the microstructure and on the surface hardness of Ti6Al4V titanium alloy was examined. The implantation process was carried out at fluences of 1 ⋅ 10{sup 17}, 2.7 ⋅ 10{sup 17} and 6 ⋅ 10{sup 17} cm{sup −2} and at ion energy 90 keV. The implanted samples were annealed at 500 °C during the implantation process. X-ray diffraction analysis was performed to obtain a phase characterization and a phase quantification in the implanted sample surface. The surface hardness was investigated by nanoindentation testing, and the nitrogen depth distribution was measured by Rutherford Backscattering Spectroscopy. Elevated temperature led to increased formation of a TiN compound. It was found that a mixture of TiN and an α-Ti(+N) solid solution had a predominant amount of TiN for samples with fluence of 2.7 ⋅ 10{sup 17} cm{sup −2} or higher. Elevated temperature during ion implantation caused an increase in surface hardening more towards the depth of the substrate in comparison with room temperature implantation. The hardness showed a remarkably significant increase at a fluence of 1 ⋅ 10{sup 17} and 2.7 ⋅ 10{sup 17} cm{sup −2} compared to samples implanted at the same fluences and at room temperature. There is a discussion of such mechanisms that explain the observed hardening more towards the depth of the substrate, and the increase in hardness.

  3. Elevation and forest clearing effects on foraging differ between surface--and subterranean--foraging army ants (Formicidae: Ecitoninae).

    Science.gov (United States)

    Kumar, Anjali; O'Donnell, Sean

    2009-01-01

    1. Forest fragmentation often results in a matrix of open areas mixed with patches of forest. Both biotic and abiotic factors can affect consumer species' ability to utilize the altered habitat, especially for species that range over large areas searching for prey. 2. Army ants (Formicidae: Ecitoninae) are highly mobile top predators in terrestrial Neotropical ecosystems. Army ant foraging behaviour is influenced by forest clearing at lowland sites, and clearing can reduce army ant population persistence. 3. Because high temperatures are implicated in hindering above-ground army ant foraging, we predicted that forest clearing effects on army ant foraging would be reduced at higher (cooler) elevations in montane forest. We also predicted that subterranean foraging, employed by some army ant species, would buffer them from the negative effects of forest clearing. 4. We quantified the foraging rates of above-ground and underground foraging army ants at eight sites along an elevational gradient from 1090 to 1540 m a.s.l. We asked whether these two foraging strategies cause a difference in the ability of army ants to forage in open matrix areas relative to elevationally matched forested habitats, and whether elevation predicts open area vs. forest foraging rate differences. 5. As predicted, army ants that forage above-ground had lower foraging rates in open areas, but the open area vs. forest difference declined with elevation. In contrast, underground foragers were not affected by habitat type, and underground foraging rates increased with elevation. Ground surface temperatures were higher in open areas than forested areas. Temperatures declined with elevation, and temperature differences between open and forested areas decreased with elevation. 6. We conclude that army ants that forage above-ground may be restricted to forested areas due to a thermal tolerance threshold, but that they are released from this limitation at higher elevations. We further suggest that

  4. Additive pressures of elevated sea surface temperatures and herbicides on symbiont-bearing foraminifera.

    Directory of Open Access Journals (Sweden)

    Joost W van Dam

    Full Text Available Elevated ocean temperatures and agrochemical pollution individually threaten inshore coral reefs, but these pressures are likely to occur simultaneously. Experiments were conducted to evaluate the combined effects of elevated temperature and the photosystem II (PSII inhibiting herbicide diuron on several types of symbiotic algae (diatom, dinoflagellate or rhodophyte of benthic foraminifera in hospite. Diuron was shown to evoke a direct effect on photosynthetic efficiency (reduced effective PSII quantum yield ΔF/F'(m, while elevated temperatures (>30 °C, only 2 °C above current average summer temperatures were observed to impact photosynthesis more indirectly by causing reductions in maximum PSII quantum yield (F(v/F(m, interpreted as photodamage. Additionally, elevated temperatures were shown to cause bleaching through loss of chlorophyll a in foraminifera hosting either diatoms or dinoflagellates. A significant linear correlation was found between reduced F(v/F(m and loss of chlorophyll a. In most cases, symbionts within foraminifera proved more sensitive to thermal stress in the presence of diuron (≥ 1 µg L(-1. The mixture toxicity model of Independent Action (IA described the combined effects of temperature and diuron on the photosystem of species hosting diatoms or dinoflagellates convincingly and in agreement with probabilistic statistics, so a response additive joint action can be assumed. We thus demonstrate that improving water quality can improve resilience of symbiotic phototrophs to projected increases in ocean temperatures. As IA described the observed combined effects from elevated temperature and diuron stress it may therefore be employed for prediction of untested mixtures and for assessing the efficacy of management measures.

  5. Additive pressures of elevated sea surface temperatures and herbicides on symbiont-bearing foraminifera.

    Science.gov (United States)

    van Dam, Joost W; Negri, Andrew P; Mueller, Jochen F; Altenburger, Rolf; Uthicke, Sven

    2012-01-01

    Elevated ocean temperatures and agrochemical pollution individually threaten inshore coral reefs, but these pressures are likely to occur simultaneously. Experiments were conducted to evaluate the combined effects of elevated temperature and the photosystem II (PSII) inhibiting herbicide diuron on several types of symbiotic algae (diatom, dinoflagellate or rhodophyte) of benthic foraminifera in hospite. Diuron was shown to evoke a direct effect on photosynthetic efficiency (reduced effective PSII quantum yield ΔF/F'(m)), while elevated temperatures (>30 °C, only 2 °C above current average summer temperatures) were observed to impact photosynthesis more indirectly by causing reductions in maximum PSII quantum yield (F(v)/F(m)), interpreted as photodamage. Additionally, elevated temperatures were shown to cause bleaching through loss of chlorophyll a in foraminifera hosting either diatoms or dinoflagellates. A significant linear correlation was found between reduced F(v)/F(m) and loss of chlorophyll a. In most cases, symbionts within foraminifera proved more sensitive to thermal stress in the presence of diuron (≥ 1 µg L(-1)). The mixture toxicity model of Independent Action (IA) described the combined effects of temperature and diuron on the photosystem of species hosting diatoms or dinoflagellates convincingly and in agreement with probabilistic statistics, so a response additive joint action can be assumed. We thus demonstrate that improving water quality can improve resilience of symbiotic phototrophs to projected increases in ocean temperatures. As IA described the observed combined effects from elevated temperature and diuron stress it may therefore be employed for prediction of untested mixtures and for assessing the efficacy of management measures.

  6. The Algorithm Theoretical Basis Document for the Derivation of Range and Range Distributions from Laser Pulse Waveform Analysis for Surface Elevations, Roughness, Slope, and Vegetation Heights

    Science.gov (United States)

    Brenner, Anita C.; Zwally, H. Jay; Bentley, Charles R.; Csatho, Bea M.; Harding, David J.; Hofton, Michelle A.; Minster, Jean-Bernard; Roberts, LeeAnne; Saba, Jack L.; Thomas, Robert H.; hide

    2012-01-01

    The primary purpose of the GLAS instrument is to detect ice elevation changes over time which are used to derive changes in ice volume. Other objectives include measuring sea ice freeboard, ocean and land surface elevation, surface roughness, and canopy heights over land. This Algorithm Theoretical Basis Document (ATBD) describes the theory and implementation behind the algorithms used to produce the level 1B products for waveform parameters and global elevation and the level 2 products that are specific to ice sheet, sea ice, land, and ocean elevations respectively. These output products, are defined in detail along with the associated quality, and the constraints, and assumptions used to derive them.

  7. Quantification of morphological properties of terrace surface using digital elevation model and its application to stratigraphic correlation of terraces

    International Nuclear Information System (INIS)

    Yamamoto, Shinya; Hataya, Ryuta; Hamada, Takaomi

    2008-01-01

    Uplift estimation during late Quaternary is required for site selection of geological disposal facility of high level radioactive waste (NUMO, 2004). Terrace level and/or difference in elevation of terraces are good indicators of uplift. Therefore, a reliable method of terrace correlation and chronology is a key issues. Air-photograph interpretation is generally carried out in the early stage of a terrace investigation. However, a terrace classification often depends on the observer's qualitative interpretation. In order to improve objectivity of geomorphic investigation with air-photograph interpretation, we examine to quantify the morphological properties of terrace surface by some morphometric variables that are computed from Digital Elevation Model (DEM). In this study, four morphometric variables (average slope, average laplacian, remaining ratio of a terrace surface, and average depth of erosion) were calculated using data sets of terraces of which chronological data are clearly described. The relationship between these variables and terrace ages shows constant tendencies respond to the geomorphological process caused by the erosion. To examine capability of morphometric variables as an index of terrace correlation, regression analyses were carried out. The regression age estimated from morphometric variables allows to classify terraces in correct sequence, and the error with the observed age falls up to 100,000 years. In addition, to discuss appropriate quantities of DEM for terrace correlation, we used three different elevation data to create DEM: 1) aerial photogrammetry data; 2) airborne laser scanner data; 3) 1:25000-scale contour map. By comparing analysis results of each DEMs, we show suitable qualities of elevation data and DEM grid size to represent the degree of erosion correctly. (author)

  8. Surface melt effects on Cryosat-2 elevation retrievals in the ablation zone of the Greenland ice sheet

    Science.gov (United States)

    Slater, T.; McMillan, M.; Shepherd, A.; Leeson, A.; Cornford, S. L.; Hogg, A.; Gilbert, L.; Muir, A. S.; Briggs, K.

    2017-12-01

    Over the past two decades, there has been an acceleration in the rate of mass losses from the Greenland ice sheet. This acceleration is, in part, attributed to an increasingly negative surface mass balance (SMB), linked to increasing melt water runoff rates due to enhanced surface melting. Understanding the past, present and future evolution in surface melting is central to ongoing monitoring of ice sheet mass balance and, in turn, to building realistic future projections. Currently, regional climate models are commonly used for this purpose, because direct in-situ observations are spatially and temporally sparse due to the logistics and resources required to collect such data. In particular, modelled SMB is used to estimate the extent and magnitude of surface melting, which influences (1) many geodetic mass balance estimates, and (2) snowpack microwave scattering properties. The latter is poorly understood and introduces uncertainty into radar altimeter estimates of ice sheet evolution. Here, we investigate the changes in CryoSat-2 waveforms and elevation measurements caused by the onset of surface melt in the summer months over the ablation zone of the Greenland ice sheet. Specifically, we use CryoSat-2 SARIn mode data acquired between 2011 and 2016, to characterise the effect of high variability in surface melt during this period, and to assess the associated impact on estimates of ice mass balance.

  9. Hydrolytic Stability of 3-Aminopropylsilane Coupling Agent on Silica and Silicate Surfaces at Elevated Temperatures

    DEFF Research Database (Denmark)

    Okhrimenko, Denis; Budi, Akin; Ceccato, Marcel

    2017-01-01

    in coupling efficiency, thus decreasing the product quality and the mechanical strength of the polymer-inorganic material interface. Therefore, a better understanding of the chemical state and stability of APS on inorganic surfaces is needed. In this work, we investigated APS adhesion on silica wafers...... and compared its properties with those on complex silicate surfaces such as those used by industry (mineral fibers and fiber melt wafers). The APS was deposited from aqueous and organic (toluene) solutions and studied with surface sensitive techniques, including X-ray photoelectron spectroscopy (XPS), atomic......- and laboratory-scale APS deposition methods and increasing adhesion and stability, thus increasing the quality and effectiveness of materials where APS is used as a coupling agent....

  10. Unmanned aerial vehicle observations of water surface elevation and bathymetry in the cenotes and lagoons of the Yucatan Peninsula, Mexico

    Science.gov (United States)

    Bandini, Filippo; Lopez-Tamayo, Alejandro; Merediz-Alonso, Gonzalo; Olesen, Daniel; Jakobsen, Jakob; Wang, Sheng; Garcia, Monica; Bauer-Gottwein, Peter

    2018-04-01

    Observations of water surface elevation (WSE) and bathymetry of the lagoons and cenotes of the Yucatán Peninsula (YP) in southeast Mexico are of hydrogeological interest. Observations of WSE (orthometric water height above mean sea level, amsl) are required to inform hydrological models, to estimate hydraulic gradients and groundwater flow directions. Measurements of bathymetry and water depth (elevation of the water surface above the bed of the water body) improve current knowledge on how lagoons and cenotes connect through the complicated submerged cave systems and the diffuse flow in the rock matrix. A novel approach is described that uses unmanned aerial vehicles (UAVs) to monitor WSE and bathymetry of the inland water bodies on the YP. UAV-borne WSE observations were retrieved using a radar and a global navigation satellite system on-board a multi-copter platform. Water depth was measured using a tethered floating sonar controlled by the UAV. This sonar provides depth measurements also in deep and turbid water. Bathymetry (wet-bed elevation amsl) can be computed by subtracting water depth from WSE. Accuracy of the WSE measurements is better than 5-7 cm and accuracy of the water depth measurements is estimated to be 3.8% of the actual water depth. The technology provided accurate measurements of WSE and bathymetry in both wetlands (lagoons) and cenotes. UAV-borne technology is shown to be a more flexible and lower cost alternative to manned aircrafts. UAVs allow monitoring of remote areas located in the jungle of the YP, which are difficult to access by human operators.

  11. Detection of surface elevation changes using an unmanned aerial vehicle on the debris-free Storbreen glacier in Norway

    Science.gov (United States)

    Kraaijenbrink, Philip; Andreassen, Liss; Immerzeel, Walter

    2016-04-01

    Recent studies have shown that the application of unmanned aerial vehicles (UAVs) has great potential to investigate the dynamic behavior of glaciers. The studies have successfully deployed UAVs over generally contrast-rich surfaces of debris-covered glaciers and highly crevassed bare ice glaciers. In this study, the potential of UAVs in glaciology is further exploited, as we use a fixed-wing UAV over the largely snow-covered Storbreen glacier in Norway in September 2015. The acquired UAV-imagery was processed into accurate digital elevation models and image mosaics using a Structure from Motion workflow. Georeferencing of the data was obtained by ingesting ground control points into the workflow that were accurately measured with a differential global navigation satellite system (DGNSS). Geodetic accuracy was determined by comparison with DGNSS surface profiles and stake positions that were measured on the same day. The processed data were compared with a LIDAR survey and airborne imagery acquisition from September and October 2009 to examine mass loss patterns and glacier retreat. Results show that the UAV is capable of producing high-quality elevation models and image mosaics for the low-contrast snow-covered Storbreen at unprecedented detail. The accuracy of the output product is lower when compared to contrast-rich debris-covered glaciers, but still considerably more accurate than spaceborne data products. Comparison with LIDAR data shows a spatially heterogeneous downwasting pattern of about 0.75 m a-1 over 2009-2015 for the upper part of Storbreen. The lower part exhibits considerably more downwasting in the range of 0.9-2.1 m a-1. We conclude that UAVs can be valuable for surveys of snow-covered glaciers to provide sufficient accurate elevation models and image mosaics, and we recommend the use of UAVs for the routine monitoring of benchmark glaciers such as Storbreen.

  12. Created mangrove wetlands store belowground carbon and surface elevation change enables them to adjust to sea-level rise.

    Science.gov (United States)

    Krauss, Ken W; Cormier, Nicole; Osland, Michael J; Kirwan, Matthew L; Stagg, Camille L; Nestlerode, Janet A; Russell, Marc J; From, Andrew S; Spivak, Amanda C; Dantin, Darrin D; Harvey, James E; Almario, Alejandro E

    2017-04-21

    Mangrove wetlands provide ecosystem services for millions of people, most prominently by providing storm protection, food and fodder. Mangrove wetlands are also valuable ecosystems for promoting carbon (C) sequestration and storage. However, loss of mangrove wetlands and these ecosystem services are a global concern, prompting the restoration and creation of mangrove wetlands as a potential solution. Here, we investigate soil surface elevation change, and its components, in created mangrove wetlands over a 25 year developmental gradient. All created mangrove wetlands were exceeding current relative sea-level rise rates (2.6 mm yr -1 ), with surface elevation change of 4.2-11.0 mm yr -1 compared with 1.5-7.2 mm yr -1 for nearby reference mangroves. While mangrove wetlands store C persistently in roots/soils, storage capacity is most valuable if maintained with future sea-level rise. Through empirical modeling, we discovered that properly designed creation projects may not only yield enhanced C storage, but also can facilitate wetland persistence perennially under current rates of sea-level rise and, for most sites, for over a century with projected medium accelerations in sea-level rise (IPCC RCP 6.0). Only the fastest projected accelerations in sea-level rise (IPCC RCP 8.5) led to widespread submergence and potential loss of stored C for created mangrove wetlands before 2100.

  13. Created mangrove wetlands store belowground carbon and surface elevation change enables them to adjust to sea-level rise

    Science.gov (United States)

    Krauss, Ken W.; Cormier, Nicole; Osland, Michael J.; Kirwan, Matthew L.; Stagg, Camille L.; Nestlerode, Janet A.; Russell, Marc J.; From, Andrew; Spivak, Amanda C.; Dantin, Darrin D.; Harvey, James E.; Almario, Alejandro E.

    2017-01-01

    Mangrove wetlands provide ecosystem services for millions of people, most prominently by providing storm protection, food and fodder. Mangrove wetlands are also valuable ecosystems for promoting carbon (C) sequestration and storage. However, loss of mangrove wetlands and these ecosystem services are a global concern, prompting the restoration and creation of mangrove wetlands as a potential solution. Here, we investigate soil surface elevation change, and its components, in created mangrove wetlands over a 25 year developmental gradient. All created mangrove wetlands were exceeding current relative sea-level rise rates (2.6 mm yr−1), with surface elevation change of 4.2–11.0 mm yr−1 compared with 1.5–7.2 mm yr−1 for nearby reference mangroves. While mangrove wetlands store C persistently in roots/soils, storage capacity is most valuable if maintained with future sea-level rise. Through empirical modeling, we discovered that properly designed creation projects may not only yield enhanced C storage, but also can facilitate wetland persistence perennially under current rates of sea-level rise and, for most sites, for over a century with projected medium accelerations in sea-level rise (IPCC RCP 6.0). Only the fastest projected accelerations in sea-level rise (IPCC RCP 8.5) led to widespread submergence and potential loss of stored C for created mangrove wetlands before 2100.

  14. Groundwater withdrawals 1976, 1990, and 2000--10 and land-surface-elevation changes 2000--10 in Harris, Galveston, Fort Bend, Montgomery, and Brazoria Counties, Texas

    Science.gov (United States)

    Kasmarek, Mark C.; Johnson, Michaela R.

    2013-01-01

    The study area comprising Harris County and parts of Galveston, Fort Bend, Montgomery, and Brazoria Counties in southeastern Texas forms part of one of the largest areas of land-surface-elevation change in the United States. Land-surface-elevation change in the study area primarily is caused by the withdrawal of groundwater. Groundwater withdrawn from the Chicot and Evangeline aquifers has been the primary source of water for municipal supply, industrial and commercial use, and irrigation in the study area. Groundwater withdrawals cause compaction of clay and silt layers abundant in the aquifers, which has in turn resulted in the widespread, substantial land-surface-elevation changes in the region with increased flooding. To estimate land-surface-elevation changes, the U.S. Geological Survey (USGS), in cooperation with the Harris-Galveston Subsidence District (HGSD), documented land-surface-elevation changes in the study area that occurred during 2000–10 and 2005–10 based on elevation data measured by 11 USGS borehole-extensometer sites, a National Geodetic Survey Continuously Operating Reference Station, and Global Positioning System Port-A-Measure (PAM) sites operated by the HGSD and the Fort Bend Subsidence District. Groundwater withdrawals in the study area also were documented for 1976, 1990, and 2000–10.

  15. Elevating your elevator talk

    Science.gov (United States)

    An important and often overlooked item that every early career researcher needs to do is compose an elevator talk. The elevator talk, named because the talk should not last longer than an average elevator ride (30 to 60 seconds), is an effective method to present your research and yourself in a clea...

  16. A New Method to Estimate Changes in Glacier Surface Elevation Based on Polynomial Fitting of Sparse ICESat—GLAS Footprints

    Directory of Open Access Journals (Sweden)

    Tianjin Huang

    2017-08-01

    Full Text Available We present in this paper a polynomial fitting method applicable to segments of footprints measured by the Geoscience Laser Altimeter System (GLAS to estimate glacier thickness change. Our modification makes the method applicable to complex topography, such as a large mountain glacier. After a full analysis of the planar fitting method to characterize errors of estimates due to complex topography, we developed an improved fitting method by adjusting a binary polynomial surface to local topography. The improved method and the planar fitting method were tested on the accumulation areas of the Naimona’nyi glacier and Yanong glacier on along-track facets with lengths of 1000 m, 1500 m, 2000 m, and 2500 m, respectively. The results show that the improved method gives more reliable estimates of changes in elevation than planar fitting. The improved method was also tested on Guliya glacier with a large and relatively flat area and the Chasku Muba glacier with very complex topography. The results in these test sites demonstrate that the improved method can give estimates of glacier thickness change on glaciers with a large area and a complex topography. Additionally, the improved method based on GLAS Data and Shuttle Radar Topography Mission-Digital Elevation Model (SRTM-DEM can give estimates of glacier thickness change from 2000 to 2008/2009, since it takes the 2000 SRTM-DEM as a reference, which is a longer period than 2004 to 2008/2009, when using the GLAS data only and the planar fitting method.

  17. Prediction of the shape of inline wave force and free surface elevation using First Order Reliability Method (FORM)

    DEFF Research Database (Denmark)

    Ghadirian, Amin; Bredmose, Henrik; Schløer, Signe

    2017-01-01

    In design of substructures for offshore wind turbines, the extreme wave loads which are of interest in Ultimate Limit States are often estimated by choosing extreme events from linear random sea states and replacing them by either stream function wave theory or the NewWave theory of a certain...... as the free surface elevation time series. The discrepancies between the FORM results and the measurements is found to be a result of more nonlinearity in the selected events than second order and negligence of the drag forces above still water level in the present analysis. This paper is one step toward more...... precise prediction of extreme wave shape and loads. Ultimately such waves can be used in the design process of offshore structures. The approach can be generalized to fully nonlinear models....

  18. De novo biofilm community assembly from tap water source communities favors Nitrotoga over Nitrospira under elevated nitrite surface loading

    DEFF Research Database (Denmark)

    Kinnunen, Marta; Dechesne, Arnaud; Albrechtsen, Hans-Jørgen

    -through biofilm system to continuous immigration from a tap water metacommunity while applying different nitrite surface loading rates. After 63 days of operation, we extracted biofilms and analyzed the community composition via Illumina MiSeq targeting the 16S rRNA gene. Previous studies have shown...... in the metacommunity, Nitrotoga and Nitrospira were found at near equal abundances, in the biofilm community, elevated nitrite loading strongly selected for Nitrotoga over Nitrospira. The biofilms were also significantly different in their alpha-diversity (p... of the biofilm community decreased significantly (p=0.004) compared to the metacommunity. These observations indicate that the selection towards Nitrotoga and Nitrospira dominated community assembly under different nitrite loadings. Lastly, we compared our observations of community composition...

  19. [Responses of rice growth and development to elevated near-surface layer ozone (O3) concentration: a review].

    Science.gov (United States)

    Yang, Lian-xin; Wang, Yu-long; Shi, Guang-yao; Wang, Yun-xia; Zhu, Jian-guo

    2008-04-01

    Ozone (O3) is recognized as one of the most important air pollutants. At present, the worldwide average tropospheric O3 concentration has been increased from an estimated pre-industrial level of 38 nl L(-1) (25-45 nl L(-1), 8-h summer seasonal average) to approximately 50 nl L(-1) in 2000, and to 80 nl L(-1) by 2100 based on most pessimistic projections. Oryza sativa L. (rice) is the most important grain crop in the world, and thus, to correctly evaluate how the elevated near-surface layer O3 concentration will affect the growth and development of rice is of great significance. This paper reviewed the chamber (including closed and open top chamber)-based studies about the effects of atmospheric ozone enrichment on the rice visible injury symptoms, photosynthesis, water relationship, phenology, dry matter production and allocation, leaf membrane protective system, and grain yield and its components. Further research directions in this field were discussed.

  20. Effects of rapid, high-dose, elevated temperature ion implantation on the microstructure and tribology of ferrous surfaces

    Science.gov (United States)

    Williamson, D. L.; Wei, R.; Wilbur, P. J.

    1991-05-01

    High-current, broad-beam ion implantation at 60 keV using a relatively simple system produces elevated target temperatures and results in remarkable enhancements in the wear resistance of ferrous materials compared to lower implantation temperatures. Effects of N, C and O implantation into AISI 304 stainless steel at 200 and 400°C on the microstructure and tribology are evaluated by conversion electron Mössbauer spectroscopy, X-ray diffraction, and a specially designed pin-on-disc tribotester. C and N implantation at 400°C yields unusually thick layers of austenite containing high concentrations of C and N in interstitial solid solution thereby accounting for the enhanced mechanical properties. O implantation at 400°C results in Fe 2O 3-like oxide rather than O in solid solution so a dispersion strengthening of the surface layer is suggested.

  1. AirSWOT observations versus hydrodynamic model outputs of water surface elevation and slope in a multichannel river

    Science.gov (United States)

    Altenau, Elizabeth H.; Pavelsky, Tamlin M.; Moller, Delwyn; Lion, Christine; Pitcher, Lincoln H.; Allen, George H.; Bates, Paul D.; Calmant, Stéphane; Durand, Michael; Neal, Jeffrey C.; Smith, Laurence C.

    2017-04-01

    Anabranching rivers make up a large proportion of the world's major rivers, but quantifying their flow dynamics is challenging due to their complex morphologies. Traditional in situ measurements of water levels collected at gauge stations cannot capture out of bank flows and are limited to defined cross sections, which presents an incomplete picture of water fluctuations in multichannel systems. Similarly, current remotely sensed measurements of water surface elevations (WSEs) and slopes are constrained by resolutions and accuracies that limit the visibility of surface waters at global scales. Here, we present new measurements of river WSE and slope along the Tanana River, AK, acquired from AirSWOT, an airborne analogue to the Surface Water and Ocean Topography (SWOT) mission. Additionally, we compare the AirSWOT observations to hydrodynamic model outputs of WSE and slope simulated across the same study area. Results indicate AirSWOT errors are significantly lower than model outputs. When compared to field measurements, RMSE for AirSWOT measurements of WSEs is 9.0 cm when averaged over 1 km squared areas and 1.0 cm/km for slopes along 10 km reaches. Also, AirSWOT can accurately reproduce the spatial variations in slope critical for characterizing reach-scale hydraulics, while model outputs of spatial variations in slope are very poor. Combining AirSWOT and future SWOT measurements with hydrodynamic models can result in major improvements in model simulations at local to global scales. Scientists can use AirSWOT measurements to constrain model parameters over long reach distances, improve understanding of the physical processes controlling the spatial distribution of model parameters, and validate models' abilities to reproduce spatial variations in slope. Additionally, AirSWOT and SWOT measurements can be assimilated into lower-complexity models to try and approach the accuracies achieved by higher-complexity models.

  2. The relation between Arctic sea ice surface elevation and draft: A case study using coincident AUV sonar and airborne scanning laser

    DEFF Research Database (Denmark)

    Doble, Martin J.; Skourup, Henriette; Wadhams, Peter

    2011-01-01

    Data are presented from a survey by airborne scanning laser profilometer and an AUV-mounted, upward looking swath sonar in the spring Beaufort Sea. The air-snow (surface elevation) and water-ice (draft) surfaces were mapped at 1 x 1 m resolution over a 300 x 300 m area. Data were separated...... into level and deformed ice fractions using the surface roughness of the sonar data. The relation (R = d/f) between draft, d, and surface elevation, f, was then examined. Correlation between top and bottom surfaces was essentially zero at full resolution, requiring averaging over patches of at least 11 m...... diameter to constrain the relation largely because of the significant error (similar to 15 cm) of the laser instrument. Level ice points were concentrated in two core regions, corresponding to level FY ice and refrozen leads, with variations in R attributed primarily to positive snow thickness variability...

  3. Elevated surface temperature depresses survival of banner-tailed kangaroo rats: will climate change cook a desert icon?

    Science.gov (United States)

    Moses, Martin R; Frey, Jennifer K; Roemer, Gary W

    2012-01-01

    Modest increases in global temperature have been implicated in causing population extirpations and range shifts in taxa inhabiting colder environs and in ectotherms whose thermoregulation is more closely tied to environmental conditions. Many arid-adapted endotherms already experience conditions at their physiological limits, so it is conceivable that they could be similarly affected by warming temperatures. We explored how climatic variables might influence the apparent survival of the banner-tailed kangaroo rat (Dipodomys spectabilis), a rodent endemic to the Chihuahuan Desert of North America and renowned for its behavioral and physiological adaptations to arid environments. Relative variable weight, strength of variable relationships, and other criteria indicated that summer, diurnal land surface temperature (SD_LST) was the primary environmental driver of apparent survival in these arid-adapted rodents. Higher temperatures had a negative effect on apparent survival, which ranged from 0.15 (SE = 0.04) for subadults to 0.50 (SE = 0.07) for adults. Elevated SD_LST may negatively influence survival through multiple pathways, including increased water loss and energy expenditure that could lead to chronic stress and/or hyperthermia that could cause direct mortality. Land surface temperatures are predicted to increase by as much 6.5°C by 2099, reducing apparent survival of adults to ~0.15 in some regions of the species' range, possibly causing a shift in their distribution. The relationship between SD_LST and survival suggests a mechanism whereby physiological tolerances are exceeded resulting in a reduction to individual fitness that may ultimately cause a shift in the species' range over time.

  4. Data Assimilation of AirSWOT and Synthetically Derived SWOT Observations of Water Surface Elevation in a Multichannel River

    Science.gov (United States)

    Altenau, E. H.; Pavelsky, T.; Andreadis, K.; Bates, P. D.; Neal, J. C.

    2017-12-01

    Multichannel rivers continue to be challenging features to quantify, especially at regional and global scales, which is problematic because accurate representations of such environments are needed to properly monitor the earth's water cycle as it adjusts to climate change. It has been demonstrated that higher-complexity, 2D models outperform lower-complexity, 1D models in simulating multichannel river hydraulics at regional scales due to the inclusion of the channel network's connectivity. However, new remote sensing measurements from the future Surface Water and Ocean Topography (SWOT) mission and it's airborne analog AirSWOT offer new observations that can be used to try and improve the lower-complexity, 1D models to achieve accuracies closer to the higher-complexity, 2D codes. Here, we use an Ensemble Kalman Filter (EnKF) to assimilate AirSWOT water surface elevation (WSE) measurements from a 2015 field campaign into a 1D hydrodynamic model along a 90 km reach of Tanana River, AK. This work is the first to test data assimilation methods using real SWOT-like data from AirSWOT. Additionally, synthetic SWOT observations of WSE are generated across the same study site using a fine-resolution 2D model and assimilated into the coarser-resolution 1D model. Lastly, we compare the abilities of AirSWOT and the synthetic-SWOT observations to improve spatial and temporal model outputs in WSEs. Results indicate 1D model outputs of spatially distributed WSEs improve as observational coverage increases, and improvements in temporal fluctuations in WSEs depend on the number of observations. Furthermore, results reveal that assimilation of AirSWOT observations produce greater error reductions in 1D model outputs compared to synthetic SWOT observations due to lower measurement errors. Both AirSWOT and the synthetic SWOT observations significantly lower spatial and temporal errors in 1D model outputs of WSEs.

  5. Transport processes associated with the initial elevated concentrations of Chernobyl radioactivity in surface air in the United States

    International Nuclear Information System (INIS)

    Larsen, R.J.; Haagenson, P.L.; Reiss, N.M.

    1989-01-01

    Elevated concentrations of radioactivity from the Chernobyl accident were encountered in the surface air over the United States along the east coast and in the north-west on 9 and 10 May 1986. The nearly simultaneous arrival of radioactive debris at widely separated locations resulted from different paths being taken by the debris released at different times during the course of the accident. Debris released during the explosion at the Chernobyl reactor was transported across the Arctic, within the lower troposphere, and zonally across Asia and the North Pacific Ocean, within the mid-troposphere. This debris descended into the planetary boundary layer along the east coast of the US. The descent was associated with a quasi-stationary cyclone located over the western North Atlantic Ocean. Debris that had a different composition of radioactivity was released from the damaged reactor during the week immediately following the initial explosion. This debris was then transported zonally across Asia and the North Pacific Ocean within the planetary boundary layer and lower troposphere and was swept into the north-western US. (author)

  6. Spatial regression between soil surface elevation, water storage in root zone and biomass productivity of alfalfa within an irrigated field

    Science.gov (United States)

    Zeyliger, Anatoly; Ermolaeva, Olga

    2014-05-01

    with formation of water flow and water storage. The major changes are formed as a result of imposing of the intensity fields on a soil surface and its field capillary infiltration rate. Excess of the first intensity over the second in each point of soil surface leads to formation of a layer of intensity of water not infiltrated in soil. Thus generate the new field of vectors of intensity which can consist of vertically directed vector of speed of evaporation, a quasi horizontal vector of intensity of a surface water flow and quasi vertical vector of intensity of a preferential flow directed downwards. Principal cause of excess of irrigation water application intensity over capillary infiltration rate can be on the one hand spatial non-uniformity of irrigation water application, and with other spatial variability of capillary infiltration rate, connected with spatial variability of water storage in the top layers of soil. As a result the spatial redistribution of irrigation water over irrigated filed forms distortions of ideal model of irrigation water storage in root zone of soil profile. The major differences consist in increasing of water storage in the depressions of a relief of an irrigated field and accordingly in their reduction on elevated zones of a relief, as well as losses of irrigation water outside of boundaries of a root zone of an irrigated field, in vertical, and horizontal directions. One of key parameters characterizing interaction between irrigation technology and soil state an irrigated field are intensity of water application, intensity and volume of a capillary infiltration, the water storage in root zone at the moment of infiltration starting and a topography of an irrigated field. Fnalyzing of spatial links between these characteristics a special research had been carried out on irrigated by sprinkler machine called Fregate at alfalfa field during the summer of 2012. This research carried out at experimental farm of the research institute Volg

  7. Changes in canopy cover alter surface air and forest floor temperature in a high-elevation red spruce (Picea rubens Sarg.) forest

    Science.gov (United States)

    Johnny L. Boggs; Steven G. McNulty

    2010-01-01

    The objective of this study is to describe winter and summer surface air and forest floor temperature patterns and diurnal fluctuations in high-elevation red spruce (Picea rubens Sarg.) forests with different levels of canopy cover. In 1988, a series of 10- x 10-meter plots (control, low nitrogen [N] addition, and high nitrogen addition) were...

  8. Chemistry and isotopic composition of precipitation and surface waters in Khumbu valley (Nepal Himalaya): N dynamics of high elevation basins.

    Science.gov (United States)

    Balestrini, Raffaella; Polesello, Stefano; Sacchi, Elisa

    2014-07-01

    We monitored the chemical and isotopic compositions of wet depositions, at the Pyramid International Laboratory (5050 ma.s.l.), and surrounding surface waters, in the Khumbu basin, to understand precipitation chemistry and to obtain insights regarding ecosystem responses to atmospheric inputs. The major cations in the precipitation were NH4(+) and Ca(2+), whereas the main anion was HCO3(-), which constituted approximately 69% of the anions, followed by NO3(-), SO4(2-) and Cl(-). Data analysis suggested that Na(+), Cl(-) and K(+) were derived from the long-range transport of marine aerosols. Ca(2+), Mg(2+) and HCO3(-) were related to rock and soil dust contributions and the NO3(-) and SO4(2-) concentrations were derived from anthropogenic sources. Furthermore, NH4(+) was derived from gaseous NH3 scavenging. The isotopic composition of weekly precipitation ranged from -1.9 to -23.2‰ in δ(18)O, and from -0.8 to -174‰ in δ(2)H, with depleted values characterizing the central part of the monsoon period. The chemical composition of the stream water was dominated by calcite and/or gypsum dissolution. However, the isotopic composition of the stream water did not fully reflect the composition of the monsoon precipitation, which suggested that other water sources contributed to the stream flow. Precipitation contents for all ions were the lowest ones among those measured in high elevation sites around the world. During the monsoon periods the depositions were not substantially influenced by anthropogenic inputs, while in pre- and post-monsoon seasons the Himalayas could not represent an effective barrier for airborne pollution. In the late monsoon phase, the increase of ionic contents in precipitation could also be due to a change in the moisture source. The calculated atmospheric N load (0.30 kg ha(-1) y(-1)) was considerably lower than the levels that were measured in other high-altitude environments. Nevertheless, the NO3(-) concentrations in the surface waters

  9. Chemistry and isotopic composition of precipitation and surface waters in Khumbu valley (Nepal Himalaya): N dynamics of high elevation basins

    International Nuclear Information System (INIS)

    Balestrini, Raffaella; Polesello, Stefano; Sacchi, Elisa

    2014-01-01

    We monitored the chemical and isotopic compositions of wet depositions, at the Pyramid International Laboratory (5050 m a.s.l.), and surrounding surface waters, in the Khumbu basin, to understand precipitation chemistry and to obtain insights regarding ecosystem responses to atmospheric inputs. The major cations in the precipitation were NH 4 + and Ca 2+ , whereas the main anion was HCO 3 − , which constituted approximately 69% of the anions, followed by NO 3 − , SO 4 2− and Cl − . Data analysis suggested that Na + , Cl − and K + were derived from the long-range transport of marine aerosols. Ca 2+ , Mg 2+ and HCO 3 − were related to rock and soil dust contributions and the NO 3 − and SO 4 2− concentrations were derived from anthropogenic sources. Furthermore, NH 4 + was derived from gaseous NH 3 scavenging. The isotopic composition of weekly precipitation ranged from − 1.9 to − 23.2‰ in δ 18 O, and from − 0.8 to − 174‰ in δ 2 H, with depleted values characterizing the central part of the monsoon period. The chemical composition of the stream water was dominated by calcite and/or gypsum dissolution. However, the isotopic composition of the stream water did not fully reflect the composition of the monsoon precipitation, which suggested that other water sources contributed to the stream flow. Precipitation contents for all ions were the lowest ones among those measured in high elevation sites around the world. During the monsoon periods the depositions were not substantially influenced by anthropogenic inputs, while in pre- and post-monsoon seasons the Himalayas could not represent an effective barrier for airborne pollution. In the late monsoon phase, the increase of ionic contents in precipitation could also be due to a change in the moisture source. The calculated atmospheric N load (0.30 kg ha −1 y −1 ) was considerably lower than the levels that were measured in other high-altitude environments. Nevertheless, the NO 3

  10. Surface Modification of Austenitic Stainless Steels by High-Flux Elevated-Temperature Nitrogen-Ion Implantation.

    Science.gov (United States)

    Ozturk, Orhan

    Nitrogen diffusivity is found to be enhanced under unusual N ion beam conditions used for modification of fcc AISI 304 stainless steel surfaces. The unusual conditions also lead to the development of various near-surface microstructures and enhanced mechanical properties. The relative importance of ion energy and current density on N penetration was studied in order to help understand the enhanced N diffusivity. The role of residual stresses in the N implanted layers was also investigated. The N beam conditions included: (1) ion beam energies from 0.4 to 60 keV; (2) beam current densities from 0.1 to 5 mA/cm^2; (3) an elevated substrate temperature of 400^ circC; (4) implantation times of 10 to 30 minutes. Mossbauer spectroscopy and x-ray diffraction (XRD) were used to characterize the near-surface N ion implanted microstructures. Supplemental data were obtained by Auger electron spectroscopy, scanning electron microscopy (SEM), magneto-optic Kerr effect (MOKE) and electron probe micro-analysis (EPMA) on selected samples. A metastable, fcc, high-N phase (gamma _{N}) is found to be generally produced in fcc 304 SS for all ion energies and current densities at 400^circC. The gamma_{N} was found to be either paramagnetic or magnetic in nature depending on the N content. With a low-energy, high-flux N beam, magnetic gamma_{N} was found to be ferromagnetic at room temperature. The N contents and depths were found to depend on the grain orientation relative to the ion beam direction for low -energy, high-flux conditions. The N was found to diffuse deeper in the (200) oriented grains compared to the (111) oriented grains and the N contents were significantly higher in the (200) planes relative to the (111) planes. Post-implantation annealing experiments showed that the magnetic gamma_{N} phase was destabilized as a result of annealing it at 400^circC, thereby resulting in thicker and predominantly paramagnetic gamma _{N} layers with less N in solution and less lattice

  11. ESA ice sheet CCI: derivation of the optimal method for surface elevation change detection of the Greenland ice sheet – round robin results

    DEFF Research Database (Denmark)

    Fredenslund Levinsen, Joanna; Khvorostovsky, Kirill; Ticconi, F.

    2015-01-01

    For more than two decades, radar altimetry missions have provided continuous elevation estimates of the Greenland ice sheet (GrIS). Here, we propose a method for using such data to estimate ice-sheet-wide surface elevation changes (SECs). The final data set will be based on observations acquired...... from the European Space Agency’s Environmental Satellite (ENVISAT), European Remote Sensing (ERS)-1 and -2, CryoSat-2, and, in the longer term, Sentinel-3 satellites. In order to find the best-performing method, an intercomparison exercise has been carried out in which the scientific community...... was asked to provide their best SEC estimates as well as feedback sheets describing the applied method. Due to the hitherto few radar-based SEC analyses as well as the higher accuracy of laser data, the participants were asked to use either ENVISAT radar or ICESat (Ice, Cloud, and land Elevation Satellite...

  12. Chemistry and isotopic composition of precipitation and surface waters in Khumbu valley (Nepal Himalaya): N dynamics of high elevation basins

    Energy Technology Data Exchange (ETDEWEB)

    Balestrini, Raffaella, E-mail: balestrini@irsa.cnr.it [Water Research Institute, National Research Council (IRSA-CNR), Via del Mulino 19, Brugherio, MB (Italy); Polesello, Stefano [Water Research Institute, National Research Council (IRSA-CNR), Via del Mulino 19, Brugherio, MB (Italy); Sacchi, Elisa [Department of Earth and Environmental Sciences, University of Pavia and IGG-CNR, Via Ferrata 1, 27100 Pavia (Italy)

    2014-07-01

    We monitored the chemical and isotopic compositions of wet depositions, at the Pyramid International Laboratory (5050 m a.s.l.), and surrounding surface waters, in the Khumbu basin, to understand precipitation chemistry and to obtain insights regarding ecosystem responses to atmospheric inputs. The major cations in the precipitation were NH{sub 4}{sup +} and Ca{sup 2+}, whereas the main anion was HCO{sub 3}{sup −}, which constituted approximately 69% of the anions, followed by NO{sub 3}{sup −}, SO{sub 4}{sup 2−} and Cl{sup −}. Data analysis suggested that Na{sup +}, Cl{sup −} and K{sup +} were derived from the long-range transport of marine aerosols. Ca{sup 2+}, Mg{sup 2+} and HCO{sub 3}{sup −} were related to rock and soil dust contributions and the NO{sub 3}{sup −} and SO{sub 4}{sup 2−} concentrations were derived from anthropogenic sources. Furthermore, NH{sub 4}{sup +} was derived from gaseous NH{sub 3} scavenging. The isotopic composition of weekly precipitation ranged from − 1.9 to − 23.2‰ in δ{sup 18}O, and from − 0.8 to − 174‰ in δ{sup 2}H, with depleted values characterizing the central part of the monsoon period. The chemical composition of the stream water was dominated by calcite and/or gypsum dissolution. However, the isotopic composition of the stream water did not fully reflect the composition of the monsoon precipitation, which suggested that other water sources contributed to the stream flow. Precipitation contents for all ions were the lowest ones among those measured in high elevation sites around the world. During the monsoon periods the depositions were not substantially influenced by anthropogenic inputs, while in pre- and post-monsoon seasons the Himalayas could not represent an effective barrier for airborne pollution. In the late monsoon phase, the increase of ionic contents in precipitation could also be due to a change in the moisture source. The calculated atmospheric N load (0.30 kg ha{sup −1} y{sup −1

  13. Temperate forest impacts on maritime snowpacks across an elevation gradient: An assessment of the snow surface energy balance and airborne lidar derived forest structure

    Science.gov (United States)

    Roth, T. R.; Nolin, A. W.

    2016-12-01

    Temperate forests modify snow evolution patterns both spatially and temporally relative to open areas. Dense, warm forests both impede snow accumulation through increased canopy snow interception and increase sub-canopy longwave energy inputs onto the snow surface. These process modifications vary in magnitude and duration depending on climatic, topographic and forest characteristics. Here we present results from a four year study of paired forested and open sites at three elevations, Low - 1150 m, Mid - 1325 m and High - 1465 m. Snowpacks are deeper and last up to 3-4 weeks longer at the Low and Mid elevation Open sites relative to the adjacent Forest sites. Conversely, at the High Forest site, snow is retained 2-4 weeks longer than the Open site. This change in snowpack depth and persistence is attributed to deposition patterns at higher elevations and forest structure differences that alter the canopy interception efficiency and the sub-canopy energy balance. Canopy interception efficiency (CIE) in the Low and Mid Forest sites, over the duration of the study were 79% and 76% of the total event snowfall, whereas CIE was 31% at the High Forest site. Longwave radiation in forested environments is the primary energy component across each elevation band due to the warm winter environment and forest presence, accounting for 82%, 88%, and 59% of the energy balance at the Low, Mid, and High Forest sites, respectively. High wind speeds in the High elevation Open site significantly increases the turbulent energy and creates preferential snowfall deposition in the nearby Forest site. These results show the importance of understanding the effects of forest cover on sub-canopy snowpack evolution and highlight the need for improved forest cover model representation to accurately predict water resources in maritime forests.

  14. Geared-elevator flutter study. [wind tunnel tests of transonic flutter effects on control surfaces of supersonic transport tail assemblies, conducted in a NASA-Langley transonic wind tunnel

    Science.gov (United States)

    Ruhlin, C. L.; Doggett, R. V., Jr.; Gregory, R. A.

    1976-01-01

    An experimental and analytical study was made of the transonic flutter characteristics of a supersonic transport tail assembly model having an all-movable, horizontal tail with a geared elevator. Two model configurations, namely, one with a gear-elevator (2.8 to 1.0 gear ratio) and one with locked-elevator (1.0 to 1.0 gear ratio), were flutter tested in the Langley transonic dynamics tunnel with an empennage cantilever-mounted on a sting. The geared-elevator configuration fluttered experimentally at about 20% higher dynamic pressures than the locked-elevator configuration. The experimental flutter dynamic pressure boundaries for both configurations were nearly flat over a Mach number range from 0.9 to 1.1. Flutter calculations (mathematical models) were made for the geared-elevator configuration using three subsonic lifting-surface methods. In one method, the elevator was treated as a discrete surface, and in the other two methods, the stabilizer and elevator were treated as a single warped-surface with the primary difference between these two methods being in the mathematical implementation used. A comparison of the experimental and analytical results shows that the discrete-elevator method predicted best the experimental flutter dynamic pressure level. However, the single warped-surface methods predicts more closely the experimental flutter frequencies and Mach number trends.

  15. Results of the measurement survey of elevation and environmental media in surface impoundments 3513 (B) and 3524 (A) at Oak Ridge National Laboratory, Oak Ridge, TN

    Energy Technology Data Exchange (ETDEWEB)

    Murray, M.E.; Rose, D.A.; Brown, K.S.; Coe, R.H.C. III; Lawrence, J.D.; Winton, W.

    1998-07-01

    A measurement survey of the elevation and environmental media in impoundments 3513 (B) and 3524 (A) at the Oak Ridge National Laboratory (ORNL) was conducted during April 1998. The investigation was performed by the Measurement Applications and Development Group of the Life Sciences Division of ORNL at the request of Bechtel Jacobs Company. Measurement activities were conducted at selected locations in order to determine the depth and appearance of the sediment and describe the clay underlying the impoundments prior to remediation. The survey was a follow-up to a previous elevation survey. The survey included the following: collection of sediment/clay cores from selected locations in each impoundment; measurement and documentation of the elevation at the water surface, at the top of sediment, at the top of clay, and at the bottom of each core; visual inspection of each core by a soil scientist to confirm the presence of clay and not material such as fly ash and soda lime compacted over the last 50 years; measurement and documentation of the background beta-gamma radiation level at the time and location of collection of each core, the highest beta-gamma level along the sediment portion of each core, and the highest beta-gamma level along the clay portion of each core; measurement and documentation of the length of the clay and of the sediment portion of each core; photographic documentation of each core; and replacement of each core in the impoundment.

  16. Results of the measurement survey of elevation and environmental media in surface impoundments 3513 (B) and 3524 (A) at Oak Ridge National Laboratory, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    Murray, M.E.; Rose, D.A.; Brown, K.S.; Coe, R.H.C. III; Lawrence, J.D.; Winton, W.

    1998-07-01

    A measurement survey of the elevation and environmental media in impoundments 3513 (B) and 3524 (A) at the Oak Ridge National Laboratory (ORNL) was conducted during April 1998. The investigation was performed by the Measurement Applications and Development Group of the Life Sciences Division of ORNL at the request of Bechtel Jacobs Company. Measurement activities were conducted at selected locations in order to determine the depth and appearance of the sediment and describe the clay underlying the impoundments prior to remediation. The survey was a follow-up to a previous elevation survey. The survey included the following: collection of sediment/clay cores from selected locations in each impoundment; measurement and documentation of the elevation at the water surface, at the top of sediment, at the top of clay, and at the bottom of each core; visual inspection of each core by a soil scientist to confirm the presence of clay and not material such as fly ash and soda lime compacted over the last 50 years; measurement and documentation of the background beta-gamma radiation level at the time and location of collection of each core, the highest beta-gamma level along the sediment portion of each core, and the highest beta-gamma level along the clay portion of each core; measurement and documentation of the length of the clay and of the sediment portion of each core; photographic documentation of each core; and replacement of each core in the impoundment

  17. Inactivation of Avian Influenza Viruses on Porous and Non-porous Surfaces is Enhanced by Elevating Absolute Humidity.

    Science.gov (United States)

    Guan, J; Chan, M; VanderZaag, A

    2017-08-01

    This study was to evaluate the effect of absolute humidity (AH), a combined factor of temperature and relative humidity (RH), on inactivation of avian influenza viruses (AIVs) on surfaces. Suspensions of the H9N2 or H6N2 AIV were deposited onto carrier surfaces that were either porous (pine wood) or non-porous (stainless steel, synthetic rubber and glass). The inoculated carriers were incubated at 23, 35 or 45°C with 25% or 55% RH for up to 28 days. After incubation, virus was recovered and quantified by chicken embryo assays. The time required to obtain a log 10 reduction in virus infectivity (D-value) was estimated using a linear regression model. At AH of 5.2 g/m 3 (23°C & 25% RH), both viruses survived up to 14 days on the porous surface and for at least 28 days on the non-porous surfaces. The corresponding D-values for H9N2 and H6N2 were 1.49 and 6.90 days on the porous surface and 7.81 and 12.5 days on the non-porous surfaces, respectively. In comparison, at AH of 9.9 g/m 3 (35°C & 25% RH) or 11.3 g/m 3 (23°C & 55% RH), the D-values for H9N2 and H6N2 dropped to ≤0.76 day on the porous surface and to ≤1.81 days on the non-porous surfaces. As the AH continued to rise from 11.3 to 36.0 g/m 3 , the D-value for both viruses decreased further. The relationship between D-value and AH followed a form of y = ax -b for both viruses. The D-values for H9N2 virus were significantly lower (P < 0.05) than those for H6N2 virus. Exposure to ammonia gas at concentrations of 86 and 173 ppm did not significantly alter test results. The findings give evidence that increasing the AH in poultry buildings following an outbreak of disease could greatly reduce the length of time required for their decontamination. © Her Majesty the Queen in Right of Canada 2016.

  18. Detection of surface elevation changes using an unmanned aerial vehicle on the debris-free Storbreen glacier in Norway

    NARCIS (Netherlands)

    Kraaijenbrink, P.D.A.; Andreassen, Liss M.; Immerzeel, W.W.

    Recent studies have shown that the application of unmanned aerial vehicles (UAVs) has great potential to investigate the dynamic behavior of glaciers. The studies have successfully deployed UAVs over generally contrast-rich surfaces of debris-covered glaciers and highly crevassed bare ice glaciers.

  19. Surface dust wipes are the best predictors of blood leads in young children with elevated blood lead levels

    Energy Technology Data Exchange (ETDEWEB)

    Gulson, Brian, E-mail: brian.gulson@mq.edu.au [Graduate School of the Environment, Macquarie University, North Ryde NSW 2109 (Australia); CSIRO Earth Science and Resource Engineering, North Ryde NSW 2113 (Australia); Anderson, Phil [Information and Statistics Group, Australian Institute of Health and Welfare, Canberra ACT 2601 (Australia); Faculty of Health, University of Canberra, Canberra ACT 2601 (Australia); Taylor, Alan [Department of Psychology, Macquarie University, Sydney NSW 2109 (Australia)

    2013-10-15

    Background: As part of the only national survey of lead in Australian children, which was undertaken in 1996, lead isotopic and lead concentration measurements were obtained from children from 24 dwellings whose blood lead levels were ≥15 µg/dL in an attempt to determine the source(s) of their elevated blood lead. Comparisons were made with data for six children with lower blood lead levels (<10 µg/dL). Methods: Thermal ionisation and isotope dilution mass spectrometry were used to determine high precision lead isotopic ratios ({sup 208}Pb/{sup 206}Pb, {sup 207}Pb/{sup 206}Pb and {sup 206}Pb/{sup 204}Pb) and lead concentrations in blood, dust from floor wipes, soil, drinking water and paint (where available). Evaluation of associations between blood and the environmental samples was based on the analysis of individual cases, and Pearson correlations and multiple regression analyses based on the whole dataset. Results and discussion: The correlations showed an association for isotopic ratios in blood and wipes (r=0.52, 95% CI 0.19–0.74), blood and soil (r=0.33, 95% CI −0.05–0.62), and blood and paint (r=0.56, 95% CI 0.09–0.83). The regression analyses indicated that the only statistically significant relationship for blood isotopic ratios was with dust wipes (B=0.65, 95% CI 0.35–0.95); there were no significant associations for lead concentrations in blood and environmental samples. There is a strong isotopic correlation of soils and house dust (r=0.53, 95% CI 0.20–0.75) indicative of a common source(s) for lead in soil and house dust. In contrast, as with the regression analyses, no such association is present for bulk lead concentrations (r=−0.003, 95% CI −0.37–0.36), the most common approach employed in source investigations. In evaluation of the isotopic results on a case by case basis, the strongest associations were for dust wipes and blood. -- Highlights: • Children with elevated blood lead ≥15 µg/dL compared with a group with <10

  20. Surface dust wipes are the best predictors of blood leads in young children with elevated blood lead levels

    International Nuclear Information System (INIS)

    Gulson, Brian; Anderson, Phil; Taylor, Alan

    2013-01-01

    Background: As part of the only national survey of lead in Australian children, which was undertaken in 1996, lead isotopic and lead concentration measurements were obtained from children from 24 dwellings whose blood lead levels were ≥15 µg/dL in an attempt to determine the source(s) of their elevated blood lead. Comparisons were made with data for six children with lower blood lead levels ( 208 Pb/ 206 Pb, 207 Pb/ 206 Pb and 206 Pb/ 204 Pb) and lead concentrations in blood, dust from floor wipes, soil, drinking water and paint (where available). Evaluation of associations between blood and the environmental samples was based on the analysis of individual cases, and Pearson correlations and multiple regression analyses based on the whole dataset. Results and discussion: The correlations showed an association for isotopic ratios in blood and wipes (r=0.52, 95% CI 0.19–0.74), blood and soil (r=0.33, 95% CI −0.05–0.62), and blood and paint (r=0.56, 95% CI 0.09–0.83). The regression analyses indicated that the only statistically significant relationship for blood isotopic ratios was with dust wipes (B=0.65, 95% CI 0.35–0.95); there were no significant associations for lead concentrations in blood and environmental samples. There is a strong isotopic correlation of soils and house dust (r=0.53, 95% CI 0.20–0.75) indicative of a common source(s) for lead in soil and house dust. In contrast, as with the regression analyses, no such association is present for bulk lead concentrations (r=−0.003, 95% CI −0.37–0.36), the most common approach employed in source investigations. In evaluation of the isotopic results on a case by case basis, the strongest associations were for dust wipes and blood. -- Highlights: • Children with elevated blood lead ≥15 µg/dL compared with a group with <10 µg/dL. • High precision lead isotopic ratios in blood, house dust wipes, soil, water, paint. • Associations for isotopic measures of blood and dust, blood and

  1. Simulation of water-surface elevations for a hypothetical 100-year peak flow in Birch Creek at the Idaho National Engineering and Environmental Laboratory, Idaho

    International Nuclear Information System (INIS)

    Berenbrock, C.; Kjelstrom, L.C.

    1997-01-01

    Delineation of areas at the Idaho National Engineering and Environmental Laboratory that would be inundated by a 100-year peak flow in Birch Creek is needed by the US Department of Energy to fulfill flood-plain regulatory requirements. Birch Creek flows southward about 40 miles through an alluvium-filled valley onto the northern part of the Idaho National Engineering and Environmental laboratory site on the eastern Snake River Plain. The lower 10-mile reach of Birch Creek that ends in Birch Creek Playa near several Idaho National Engineering and Environmental Laboratory facilities is of particular concern. Twenty-six channel cross sections were surveyed to develop and apply a hydraulic model to simulate water-surface elevations for a hypothetical 100-year peak flow in Birch Creek. Model simulation of the 100-year peak flow (700 cubic feet per second) in reaches upstream from State Highway 22 indicated that flow was confined within channels even when all flow was routed to one channel. Where the highway crosses Birch Creek, about 315 cubic feet per second of water was estimated to move downstream--115 cubic feet per second through a culvert and 200 cubic feet per second over the highway. Simulated water-surface elevation at this crossing was 0.8 foot higher than the elevation of the highway. The remaining 385 cubic feet per second flowed southwestward in a trench along the north side of the highway. Flow also was simulated with the culvert removed. The exact location of flood boundaries on Birch Creek could not be determined because of the highly braided channel and the many anthropogenic features (such as the trench, highway, and diversion channels) in the study area that affect flood hydraulics and flow. Because flood boundaries could not be located exactly, only a generalized flood-prone map was developed

  2. Nanoripple formation on GaAs (001) surface by reverse epitaxy during ion beam sputtering at elevated temperature

    Energy Technology Data Exchange (ETDEWEB)

    Chowdhury, Debasree; Ghose, Debabrata, E-mail: debabrata1.ghose@gmail.com

    2016-11-01

    Highlights: • GaAs (001) surfaces are sputtered by 1 keV Ar{sup +} at sample temperature of 450 °C. • Highly ordered defect-free ripples develop at near-normal incidence angles (θ ≈ 0–25{sup 0}). • Concurrent sample rotation does not alter the ripple orientation with respect to the ion beam. • At grazing incidence angles anisotropic structure is formed. • Concurrent sample rotation shows that the structure orientation depends on the beam direction. - Abstract: Self-organized pattern formation by the process of reverse epitaxial growth has been investigated on GaAs (001) surfaces during 1 keV Ar{sup +} bombardment at target temperature of 450 °C for a wide range of incident angles. Highly ordered ripple formation driven by diffusion instability is evidenced at near normal incidence angles. Concurrent sample rotation shows that the ripple morphology and its orientation do not depend on the incident beam direction; rather they are determined by the symmetry of the crystal face.

  3. Keratoconus Progression in Patients With Allergy and Elevated Surface Matrix Metalloproteinase 9 Point-of-Care Test.

    Science.gov (United States)

    Mazzotta, Cosimo; Traversi, Claudio; Mellace, Pierfrancesco; Bagaglia, Simone A; Zuccarini, Silvio; Mencucci, Rita; Jacob, Soosan

    2017-10-04

    To assess keratoconus (KC) progression in patients with allergies who also tested positive to surface matrix metalloproteinase 9 (MMP-9) point-of-care test. Prospective comparative study including 100 stage I-II keratoconic patients, mean age 16.7±4.6 years. All patients underwent an anamnestic questionnaire for concomitant allergic diseases and were screened with the MMP-9 point-of-care test. Patients were divided into two groups: patients KC with allergies (KC AL) and patients KC without allergies (KC NAL). Severity of allergy was established by papillary subtarsal response grade and KC progression assessed by Scheimpflug corneal tomography, corrected distance visual acuity (CDVA) measurement in a 12-month follow-up. The KC AL group included 52 patients and the KC NAL group 48. In the KC AL group, 42/52 of patients (81%) were positive to MMP-9 point-of-care test versus two positive patients in the KC NAL group (4%). The KC AL group data showed a statistically significant decrease of average CDVA, from 0.155±0.11 to 0.301±0.2 logarithm of the minimum angle of resolution (Paverage. The KC NAL group revealed a slight KC progression without statistically significant changes. Pearson correlation test showed a high correlation between Kmax worsening and severity of PSR in the KC AL group. The study demonstrated a statistically significant progression of KC in patients with concomitant allergies, positive to MMP-9 point-of-care test versus negative. A high correlation between severity of allergy and KC progression was documented.

  4. [Ca2+]i Elevation and Oxidative Stress Induce KCNQ1 Protein Translocation from the Cytosol to the Cell Surface and Increase Slow Delayed Rectifier (IKs) in Cardiac Myocytes*

    Science.gov (United States)

    Wang, Yuhong; Zankov, Dimitar P.; Jiang, Min; Zhang, Mei; Henderson, Scott C.; Tseng, Gea-Ny

    2013-01-01

    Our goals are to simultaneously determine the three-dimensional distribution patterns of KCNQ1 and KCNE1 in cardiac myocytes and to study the mechanism and functional implications for variations in KCNQ1/KCNE1 colocalization in myocytes. We monitored the distribution patterns of KCNQ1, KCNE1, and markers for subcellular compartments/organelles using immunofluorescence/confocal microscopy and confirmed the findings in ventricular myocytes by directly observing fluorescently tagged KCNQ1-GFP and KCNE1-dsRed expressed in these cells. We also monitored the effects of stress on KCNQ1-GFP and endoplasmic reticulum (ER) remodeling during live cell imaging. The data showed that 1) KCNE1 maintained a stable cell surface localization, whereas KCNQ1 exhibited variations in the cytosolic compartment (striations versus vesicles) and the degree of presence on the cell surface; 2) the degree of cell surface KCNQ1/KCNE1 colocalization was positively correlated with slow delayed rectifier (IKs) current density; 3) KCNQ1 and calnexin (an ER marker) shared a cytosolic compartment; and 4) in response to stress ([Ca2+]i elevation, oxidative overload, or AT1R stimulation), KCNQ1 exited the cytosolic compartment and trafficked to the cell periphery in vesicles. This was accompanied by partial ER fragmentation. We conclude that the cellular milieu regulates KCNQ1 distribution in cardiac myocytes and that stressful conditions can increase IKs by inducing KCNQ1 movement to the cell surface. This represents a hitherto unrecognized mechanism by which IKs fulfills its function as a repolarization reserve in ventricular myocytes. PMID:24142691

  5. [Ca2+]i elevation and oxidative stress induce KCNQ1 protein translocation from the cytosol to the cell surface and increase slow delayed rectifier (IKs) in cardiac myocytes.

    Science.gov (United States)

    Wang, Yuhong; Zankov, Dimitar P; Jiang, Min; Zhang, Mei; Henderson, Scott C; Tseng, Gea-Ny

    2013-12-06

    Our goals are to simultaneously determine the three-dimensional distribution patterns of KCNQ1 and KCNE1 in cardiac myocytes and to study the mechanism and functional implications for variations in KCNQ1/KCNE1 colocalization in myocytes. We monitored the distribution patterns of KCNQ1, KCNE1, and markers for subcellular compartments/organelles using immunofluorescence/confocal microscopy and confirmed the findings in ventricular myocytes by directly observing fluorescently tagged KCNQ1-GFP and KCNE1-dsRed expressed in these cells. We also monitored the effects of stress on KCNQ1-GFP and endoplasmic reticulum (ER) remodeling during live cell imaging. The data showed that 1) KCNE1 maintained a stable cell surface localization, whereas KCNQ1 exhibited variations in the cytosolic compartment (striations versus vesicles) and the degree of presence on the cell surface; 2) the degree of cell surface KCNQ1/KCNE1 colocalization was positively correlated with slow delayed rectifier (IKs) current density; 3) KCNQ1 and calnexin (an ER marker) shared a cytosolic compartment; and 4) in response to stress ([Ca(2+)]i elevation, oxidative overload, or AT1R stimulation), KCNQ1 exited the cytosolic compartment and trafficked to the cell periphery in vesicles. This was accompanied by partial ER fragmentation. We conclude that the cellular milieu regulates KCNQ1 distribution in cardiac myocytes and that stressful conditions can increase IKs by inducing KCNQ1 movement to the cell surface. This represents a hitherto unrecognized mechanism by which IKs fulfills its function as a repolarization reserve in ventricular myocytes.

  6. Data Elevator

    Energy Technology Data Exchange (ETDEWEB)

    2017-04-29

    Data Elevator: Efficient Asynchronous Data Movement in Hierarchical Storage Systems Multi-layer storage subsystems, including SSD-based burst buffers and disk-based parallel file systems (PFS), are becoming part of HPC systems. However, software for this storage hierarchy is still in its infancy. Applications may have to explicitly move data among the storage layers. We propose Data Elevator for transparently and efficiently moving data between a burst buffer and a PFS. Users specify the final destination for their data, typically on PFS, Data Elevator intercepts the I/O calls, stages data on burst buffer, and then asynchronously transfers the data to their final destination in the background. This system allows extensive optimizations, such as overlapping read and write operations, choosing I/O modes, and aligning buffer boundaries. In tests with large-scale scientific applications, Data Elevator is as much as 4.2X faster than Cray DataWarp, the start-of-art software for burst buffer, and 4X faster than directly writing to PFS. The Data Elevator library uses HDF5's Virtual Object Layer (VOL) for intercepting parallel I/O calls that write data to PFS. The intercepted calls are redirected to the Data Elevator, which provides a handle to write the file in a faster and intermediate burst buffer system. Once the application finishes writing the data to the burst buffer, the Data Elevator job uses HDF5 to move the data to final destination in an asynchronous manner. Hence, using the Data Elevator library is currently useful for applications that call HDF5 for writing data files. Also, the Data Elevator depends on the HDF5 VOL functionality.

  7. Mechanism of degradation of surface hardening at elevated temperature in TiAlV-alloys by in situ synchrotron radiation diffraction

    CERN Document Server

    Berberich, F; Kreissig, U; Schell, N; Mücklich, A

    2003-01-01

    The surface hardness of the technically important alloy Ti-6Al-4V (wt.%) can be improved by nitrogen implantation. The structural mechanisms of hardening and of the stability of the improved hardness at elevated temperatures are studied. Ion implanted (II) and plasma immersion ion implanted (PII) samples were used. The formation of small TiN crystallites was detected in the as-implanted state, but only for the II samples a considerable surface hardness increase (factor 3) is observed. The in situ XRD experiments showed, that the TiN phase is stable up to temperatures of 650 deg. C for both types of implantation. At higher temperature Ti sub 2 N is formed which is stable up to 770 deg. C. ERDA results indicate a diffusion of nitrogen into the bulk material. The redistribution of N is responsible for the hardness changes: a slight decrease for II samples but an improvement by a factor of 2.5 for PII samples. The improvements/degradations of hardness and wear are discussed in correlation with the nitrogen depth ...

  8. Monocular Elevation Deficiency - Double Elevator Palsy

    Science.gov (United States)

    ... Español Condiciones Chinese Conditions Monocular Elevation Deficiency/ Double Elevator Palsy En Español Read in Chinese What is monocular elevation deficiency (Double Elevator Palsy)? Monocular Elevation Deficiency, also known by the ...

  9. Consolidated ethanol production from Jerusalem artichoke tubers at elevated temperature by Saccharomyces cerevisiae engineered with inulinase expression through cell surface display.

    Science.gov (United States)

    Khatun, M Mahfuza; Liu, Chen-Guang; Zhao, Xin-Qing; Yuan, Wen-Jie; Bai, Feng-Wu

    2017-02-01

    Ethanol fermentation from Jerusalem artichoke tubers was performed at elevated temperatures by the consolidated bioprocessing strategy using Saccharomyces cerevisiae MK01 expressing inulinase through cell surface display. No significant difference was observed in yeast growth when temperature was controlled at 38 and 40 °C, respectively, but inulinase activity with yeast cells was substantially enhanced at 40 °C. As a result, enzymatic hydrolysis of inulin was facilitated and ethanol production was improved with 89.3 g/L ethanol produced within 72 h from 198.2 g/L total inulin sugars consumed. Similar results were also observed in ethanol production from Jerusalem artichoke tubers with 85.2 g/L ethanol produced within 72 h from 185.7 g/L total sugars consumed. On the other hand, capital investment on cooling facilities and energy consumption for running the facilities would be saved, since regular cooling water instead of chill water could be used to cool down the fermentation system.

  10. Validation and inter-comparison of surface elevation changes derived from altimetry over the Jakobshavn Isbræ drainage basin, Greenland – Round Robin results from ESA's Ice_Sheets_CCI (ID #EGU2013-6007)

    DEFF Research Database (Denmark)

    Fredenslund Levinsen, Joanna; Khvorostovsky, Kirill; Ticconi, Francesca

    elevation changes (SEC), surface velocities, calving front locations, and grounding line locations. This work focuses on SEC, and the goal is to develop the best routine for estimating this by means of radar altimetry. In order to find the most optimal approach we have completed a Round Robin experiment (RR...

  11. An elevator

    Energy Technology Data Exchange (ETDEWEB)

    Rastorguyev, M.A.; Maloyarovslavtesv, D.A.; Prokopov, O.I.; Tukayev, Sh.V.; Zanilov, I.F.

    1983-01-01

    An elevator is proposed which includes a body with a turning collar locking device and a rod with longitudinal grooves, which are flexibly linked with jaws positioned in grooves in the body. To increase safety through ensuring automatic locking of the jaws in the closed position, the locking device is made in the form of head on wedges, spring loaded relative to the collar and made with cams and positioned with the capability of interacting with the grooves of the rod and through the cams with the collar.

  12. Bucket elevator

    OpenAIRE

    Chromek, Jiří

    2013-01-01

    Cílem této bakalářské práce je návrh svislého korečkového elevátoru, který má sloužit k dopravě obilovin s dopravní výškou 19 m a dopravovaným množstvím 100 t/hod. Práce se skládá z popisu korečkového elevátoru a jeho hlavních částí, zmiňující se v úvodní rešerši. Tato práce je zaměřena na funkční a kapacitní výpočet, určení pohonu a napínacího zařízení. Další výpočet je kontrolní, skládající se z pevnostní kontroly hnacího hřídele, výpočtu pera, životnosti ložisek a výpočtu napínacího zaříze...

  13. Effect of uncertainty in surface mass balance–elevation feedback on projections of the future sea level contribution of the Greenland ice sheet

    Directory of Open Access Journals (Sweden)

    T. L. Edwards

    2014-01-01

    Régional: Fettweis, 2007 climate projections are for 2000–2199, forced by the ECHAM5 and HadCM3 global climate models (GCMs under the SRES A1B emissions scenario. The additional sea level contribution due to the SMB–elevation feedback averaged over five ISM projections for ECHAM5 and three for HadCM3 is 4.3% (best estimate; 95% credibility interval 1.8–6.9% at 2100, and 9.6% (best estimate; 95% credibility interval 3.6–16.0% at 2200. In all results the elevation feedback is significantly positive, amplifying the GrIS sea level contribution relative to the MAR projections in which the ice sheet topography is fixed: the lower bounds of our 95% credibility intervals (CIs for sea level contributions are larger than the "no feedback" case for all ISMs and GCMs. Our method is novel in sea level projections because we propagate three types of modelling uncertainty – GCM and ISM structural uncertainties, and elevation feedback parameterisation uncertainty – along the causal chain, from SRES scenario to sea level, within a coherent experimental design and statistical framework. The relative contributions to uncertainty depend on the timescale of interest. At 2100, the GCM uncertainty is largest, but by 2200 both the ISM and parameterisation uncertainties are larger. We also perform a perturbed parameter ensemble with one ISM to estimate the shape of the projected sea level probability distribution; our results indicate that the probability density is slightly skewed towards higher sea level contributions.

  14. An X-ray photoelectron spectroscopic study of a nitric acid/argon ion cleaned uranium metal surface at elevated temperature

    International Nuclear Information System (INIS)

    Paul, A.J.; Sherwood, P.M.A.

    1987-01-01

    X-ray photoelectron spectroscopy has been used to study the surface of uranium metal cleaned by nitric acid treatment and argon ion etching, followed by heating in a high vacuum. The surface is shown to contain UOsub(2-x) species over the entire temperature range studied. Heating to temperatures in the range 400-600 0 C generates a mixture of this oxide, the metal and a carbide and/or oxycarbide species. (author)

  15. Adenosine monophosphate is elevated in the bronchoalveolar lavage fluid of mice with acute respiratory toxicity induced by nanoparticles with high surface hydrophobicity.

    Science.gov (United States)

    Dailey, Lea Ann; Hernández-Prieto, Raquel; Casas-Ferreira, Ana Maria; Jones, Marie-Christine; Riffo-Vasquez, Yanira; Rodríguez-Gonzalo, Encarnación; Spina, Domenico; Jones, Stuart A; Smith, Norman W; Forbes, Ben; Page, Clive; Legido-Quigley, Cristina

    2015-02-01

    Inhaled nanomaterials present a challenge to traditional methods and understanding of respiratory toxicology. In this study, a non-targeted metabolomics approach was used to investigate relationships between nanoparticle hydrophobicity, inflammatory outcomes and the metabolic fingerprint in bronchoalveolar fluid. Measures of acute lung toxicity were assessed following single-dose intratracheal administration of nanoparticles with varying surface hydrophobicity (i.e. pegylated lipid nanocapsules, polyvinyl acetate nanoparticles and polystyrene beads; listed in order of increasing hydrophobicity). Broncho-alveolar lavage (BAL) fluid was collected from mice exposed to nanoparticles at a surface area dose of 220 cm(2) and metabolite fingerprints were acquired via ultra pressure liquid chromatography-mass spectrometry-based metabolomics. Particles with high surface hydrophobicity were pro-inflammatory. Multivariate analysis of the resultant small molecule fingerprints revealed clear discrimination between the vehicle control and polystyrene beads (p < 0.05), as well as between nanoparticles of different surface hydrophobicity (p < 0.0001). Further investigation of the metabolic fingerprints revealed that adenosine monophosphate (AMP) concentration in BAL correlated with neutrophilia (p < 0.01), CXCL1 levels (p < 0.05) and nanoparticle surface hydrophobicity (p < 0.001). Our results suggest that extracellular AMP is an intermediary metabolite involved in adenine nucleotide-regulated neutrophilic inflammation as well as tissue damage, and could potentially be used to monitor nanoparticle-induced responses in the lung following pulmonary administration.

  16. High Surface Area Tungsten Carbides: Synthesis, Characterization and Catalytic Activity towards the Hydrogen Evolution Reaction in Phosphoric Acid at Elevated Temperatures

    DEFF Research Database (Denmark)

    Tomás García, Antonio Luis; Li, Qingfeng; Jensen, Jens Oluf

    2014-01-01

    Tungsten carbide powders were synthesized as a potential electrocatalyst for the hydrogen evolution reaction in phosphoric acid at elevated temperatures. With ammonium metatungstate as the precursor, two synthetic routes with and without carbon templates were investigated. Through the intermediate...... nitride route and with carbon black as template, the obtained tungsten carbide samples had higher BET area. In 100% H3PO4 at temperatures up to 185°C, the carbide powders showed superior activity towards the hydrogen evolution reaction. A deviation was found in the correlation between the BET area...... and catalytic activity; this was attributed to the presence of excess amorphous carbon in the carbide powder. TEM imaging and TGA-DTA results revealed a better correlation of the activity with the carbide particle size....

  17. Dry Eye Profiles in Patients with a Positive Elevated Surface Matrix Metalloproteinase 9 Point-of-Care Test Versus Negative Patients.

    Science.gov (United States)

    Lanza, Nicole L; McClellan, Allison L; Batawi, Hatim; Felix, Elizabeth R; Sarantopoulos, Konstantinos D; Levitt, Roy C; Galor, Anat

    2016-04-01

    To compare dry eye (DE) symptoms and signs in subjects who tested positive versus those who tested negative for ocular surface matrix metalloproteinase 9 (MMP-9) using the InflammaDry point-of-care test (RPS, Sarasota, FL). In this cross-sectional study, individuals seen in the Miami Veterans Affairs eye clinic with DE symptoms, as evidenced by DE questionnaire 5 (DEQ5) ≥6, were given standardized questionnaires to assess DE symptoms and ocular and non-ocular pain complaints. Also, a complete evaluation was conducted to measure ocular surface signs of DE. MMP-9 testing was performed using the InflammaDry once in each eye, per the manufacturer's instructions. The main outcome measure was a comparison of DE symptoms and signs in MMP-9 positive versus negative subjects. Of 128 subjects, 50 (39%) were positive for MMP-9 for InflammaDry testing in either eye. No statistically significant differences in mental health indices, DE symptoms, or ocular surface signs were seen in subjects based on MMP-9 status. In our population, there was no difference in the DE profile by both symptoms and signs between those testing positive versus negative for MMP-9 on the ocular surface. This suggests that clinical exam alone cannot predict patients with clinically significant inflammation. Published by Elsevier Inc.

  18. Elevated Liver Enzymes

    Science.gov (United States)

    Symptoms Elevated liver enzymes By Mayo Clinic Staff Elevated liver enzymes may indicate inflammation or damage to cells in the liver. Inflamed or ... than normal amounts of certain chemicals, including liver enzymes, into the bloodstream, which can result in elevated ...

  19. National Elevation Dataset (NED)

    Data.gov (United States)

    Kansas Data Access and Support Center — The U.S. Geological Survey has developed a National Elevation Database (NED). The NED is a seamless mosaic of best-available elevation data. The 7.5-minute elevation...

  20. ESA's Ice Sheets CCI: validation and inter-comparison of surface elevation changes derived from laser and radar altimetry over Jakobshavn Isbræ, Greenland – Round Robin results

    DEFF Research Database (Denmark)

    Fredenslund Levinsen, Joanna; Khvorostovsky, K.; Ticconi, F.

    2013-01-01

    Sheets CCI and four parameters are to be determined for the Greenland Ice Sheet (GrIS), each resulting in a dataset made available to the public: Surface Elevation Changes (SEC), surface velocities, grounding line locations, and calving front locations. All CCI projects have completed a so-called Round...... Robin exercise in which the scientific community was asked to provide their best estimate of the sought parameters as well as a feedback sheet describing their work. By inter-comparing and validating the results, obtained from research institutions world-wide, it is possible to develop the most optimal...... led to inter-comparisons of radar vs. altimetry as well as cross-over vs. repeat-track analyses. Due to the high accuracy of the former and the high spatial resolution of the latter, a method, which combines the two techniques will provide the most accurate SEC estimates. The data supporting the final...

  1. α-TEA-induced death receptor dependent apoptosis involves activation of acid sphingomyelinase and elevated ceramide-enriched cell surface membranes

    Directory of Open Access Journals (Sweden)

    Xiong Ailian

    2010-10-01

    Full Text Available Abstract Background Alpha-tocopherol ether-linked acetic acid (α-TEA, an analog of vitamin E (RRR-alpha-tocopherol, is a potent and selective apoptosis-inducing agent for human cancer cells in vivo and in vitro. α-TEA induces apoptosis via activation of extrinsic death receptors Fas (CD95 and DR5, JNK/p73/Noxa pathways, and suppression of anti-apoptotic mediators Akt, ERK, c-FLIP and survivin in breast, ovarian and prostate cancer cells. Results In this study, we demonstrate that α-TEA induces the accumulation of cell surface membrane ceramide, leading to co-localization with Fas, DR5, and FADD, followed by activation of caspases-8 and -9 and apoptosis in human MDA-MB-231 breast cancer cells. α-TEA treatment leads to increased acid sphingomyelinase (ASMase activity by 30 min, peaking at 4 hrs, which is correlated with ASMase translocation from cytosol to the cell surface membrane. Functional knockdown of ASMase with either the chemical inhibitor, desipramine, or siRNA markedly reduces α-TEA-induced cell surface membrane accumulation of ceramide and its co-localization with Fas, DR5, and FADD, cleavage of caspases-8 and -9 and apoptosis, suggesting an early and critical role for ASMase in α-TEA-induced apoptosis. Consistent with cell culture data, immunohistochemical analyses of tumor tissues taken from α-TEA treated nude mice bearing MDA-MB-231 xenografts show increased levels of cell surface membrane ceramide in comparison to tumor tissues from control animals. Conclusion Taken together, these studies demonstrate that ASMase activation and membrane ceramide accumulation are early events contributing to α-TEA-induced apoptosis in vitro and perhaps in vivo.

  2. The Use of Flexible Ultrasound Transducers for the Detection of Laser-Induced Guided Waves on Curved Surfaces at Elevated Temperatures

    Directory of Open Access Journals (Sweden)

    Tai Chieh Wu

    2017-06-01

    Full Text Available In this study, a flexible ultrasonic transducer (FUT was applied in a laser ultrasonic technique (LUT for non-destructive characterization of metallic pipes at high temperatures of up to 176 °C. Compared with normal ultrasound transducers, a FUT is a piezoelectric film made of a PZT/PZT sol-gel composite which has advantages due to its high sensitivity, curved surface adaptability and high temperature durability. By operating a pulsed laser in B-scan mode along with the integration of FUT and LUT, a multi-mode dispersion spectrum of a stainless steel pipe at high temperature can be measured. In addition, dynamic wave propagation behaviors are experimentally visualized with two dimensional scanning. The images directly interpret the reflections from the interior defects and also can locate their positions. This hybrid technique shows great potential for non-destructive evaluation of structures with complex geometry, especially in high temperature environments.

  3. The Use of Flexible Ultrasound Transducers for the Detection of Laser-Induced Guided Waves on Curved Surfaces at Elevated Temperatures.

    Science.gov (United States)

    Wu, Tai Chieh; Kobayashi, Makiko; Tanabe, Masayuki; Yang, Che Hua

    2017-06-04

    In this study, a flexible ultrasonic transducer (FUT) was applied in a laser ultrasonic technique (LUT) for non-destructive characterization of metallic pipes at high temperatures of up to 176 °C. Compared with normal ultrasound transducers, a FUT is a piezoelectric film made of a PZT/PZT sol-gel composite which has advantages due to its high sensitivity, curved surface adaptability and high temperature durability. By operating a pulsed laser in B-scan mode along with the integration of FUT and LUT, a multi-mode dispersion spectrum of a stainless steel pipe at high temperature can be measured. In addition, dynamic wave propagation behaviors are experimentally visualized with two dimensional scanning. The images directly interpret the reflections from the interior defects and also can locate their positions. This hybrid technique shows great potential for non-destructive evaluation of structures with complex geometry, especially in high temperature environments.

  4. EFFECTS OF ELEVATED TEMPERATURE ON ELEVATED ...

    African Journals Online (AJOL)

    eobe

    concrete. Data obtained at 7 and 28 days for the effects of temperature with compressive strength are shown in Tables 1 and 2 respectively while the loss of weight as related to elevated temperature and age, are in. Figure 1. The effect of elevated temperature on the compressive strength at 7 days and 28 days for concrete ...

  5. Myocardium at risk in ST-segment elevation myocardial infarction comparison of T2-weighted edema imaging with the MR-assessed endocardial surface area and validation against angiographic scoring.

    Science.gov (United States)

    Fuernau, Georg; Eitel, Ingo; Franke, Vinzenz; Hildebrandt, Lysann; Meissner, Josefine; de Waha, Suzanne; Lurz, Philipp; Gutberlet, Matthias; Desch, Steffen; Schuler, Gerhard; Thiele, Holger

    2011-09-01

    The objective of this study was to assess the area at risk (AAR) in ST-segment elevation myocardial infarction with 2 different cardiac magnetic resonance (CMR) imaging methods and to compare them with the validated angiographic Alberta Provincial Project for Outcome Assessment in Coronary Heart Disease Score (APPROACH-score) in a large consecutive patient cohort. Edema imaging with T(2)-weighted CMR and the endocardial surface area (ESA) assessed by late gadolinium enhancement have been introduced as relatively new methods for AAR assessment in ST-segment elevation myocardial infarction. However, data on the utility and validation of these techniques are limited. A total of 197 patients undergoing primary percutaneous coronary intervention in acute ST-segment elevation myocardial infarction were included. AAR (assessed with T(2)-weighted edema imaging and the ESA method), infarct size, and myocardial salvage (AAR minus infarct size) were determined by CMR 2 to 4 days after primary angioplasty. Angiographic AAR scoring was performed by use of the APPROACH-score. All measurements were done offline by blinded observers. The AAR assessed by T(2)-weighted imaging showed good correlation with the angiographic AAR (r = 0.87; p myocardial salvage index. In contrast, no dependence of T(2)-weighted edema imaging or the APPROACH-score on myocardial salvage index was seen. The AAR can be reliably assessed by T(2)-weighted CMR, whereas assessment of the AAR by ESA seems to be dependent on the degree of myocardial salvage, thereby underestimating the AAR in patients with high myocardial salvage such as aborted infarction. Thus, assessment of the AAR with the ESA method cannot be recommended. (Myocardial Salvage and Contrast Dye Induced Nephropathy Reduction by N-Acetylcystein [LIPSIA-N-ACC]; NCT00463749). Copyright © 2011 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  6. A versatile elevated-pressure reactor combined with an ultrahigh vacuum surface setup for efficient testing of model and powder catalysts under clean gas-phase conditions

    Energy Technology Data Exchange (ETDEWEB)

    Morfin, Franck; Piccolo, Laurent [Institut de recherches sur la catalyse et l' environnement de Lyon (IRCELYON), UMR 5256 CNRS and Université Lyon 1, 2 avenue Albert Einstein, F-69626 Villeurbanne (France)

    2013-09-15

    A small-volume reaction cell for catalytic or photocatalytic testing of solid materials at pressures up to 1000 Torr has been coupled to a surface-science setup used for standard sample preparation and characterization under ultrahigh vacuum (UHV). The reactor and sample holder designs allow easy sample transfer from/to the UHV chamber, and investigation of both planar and small amounts of powder catalysts under the same conditions. The sample is heated with an infrared laser beam and its temperature is measured with a compact pyrometer. Combined in a regulation loop, this system ensures fast and accurate temperature control as well as clean heating. The reaction products are automatically sampled and analyzed by mass spectrometry and/or gas chromatography (GC). Unlike previous systems, our GC apparatus does not use a recirculation loop and allows working in clean conditions at pressures as low as 1 Torr while detecting partial pressures smaller than 10{sup −4} Torr. The efficiency and versatility of the reactor are demonstrated in the study of two catalytic systems: butadiene hydrogenation on Pd(100) and CO oxidation over an AuRh/TiO{sub 2} powder catalyst.

  7. Cokriging model for estimation of water table elevation

    International Nuclear Information System (INIS)

    Hoeksema, R.J.; Clapp, R.B.; Thomas, A.L.; Hunley, A.E.; Farrow, N.D.; Dearstone, K.C.

    1989-01-01

    In geological settings where the water table is a subdued replica of the ground surface, cokriging can be used to estimate the water table elevation at unsampled locations on the basis of values of water table elevation and ground surface elevation measured at wells and at points along flowing streams. The ground surface elevation at the estimation point must also be determined. In the proposed method, separate models are generated for the spatial variability of the water table and ground surface elevation and for the dependence between these variables. After the models have been validated, cokriging or minimum variance unbiased estimation is used to obtain the estimated water table elevations and their estimation variances. For the Pits and Trenches area (formerly a liquid radioactive waste disposal facility) near Oak Ridge National Laboratory, water table estimation along a linear section, both with and without the inclusion of ground surface elevation as a statistical predictor, illustrate the advantages of the cokriging model

  8. Troponin elevation in subarachnoid hemorrhage

    Directory of Open Access Journals (Sweden)

    Ioannis N. Mavridis

    2015-03-01

    Full Text Available Troponin (tr elevation in aneurysmal subarachnoid hemorrhage (SAH patients is often difficult to be appropriately assessed by clinicians, causing even disagreements regarding its management between neurosurgeons and cardiologists. The purpose of this article was to review the literature regarding the clinical interpretation of tr elevation in SAH. We searched for articles in PubMed using the key words: “troponin elevation” and “subarachnoid hemorrhage”. All of them, as well as relative neurosurgical books, were used for this review. Some type of cardiovascular abnormality develops in most SAH patients. Neurogenic stunned myocardium is a frequent SAH complication, due to catecholamine surge which induces cardiac injury, as evidenced by increased serum tr levels, electrocardiographic (ECG changes and cardiac wall motion abnormalities. Tr elevation, usually modest, is an early and specific marker for cardiac involvement after SAH and its levels peak about two days after SAH. Cardiac tr elevation predictors include poor clinical grade, intraventricular hemorrhage, loss of consciousness at ictus, global cerebral edema, female sex, large body surface area, lower systolic blood pressure, higher heart rate and prolonged Q-Tc interval. Elevated tr levels are associated with disability and death (especially tr >1 μg/L, worse neurological grade, systolic and diastolic cardiac dysfunction, pulmonary congestion, longer intensive care unit stay and incidence of vasospasm. Tr elevation is a common finding in SAH patients and constitutes a rightful cause of worry about the patients' cardiac function and prognosis. It should be therefore early detected, carefully monitored and appropriately managed by clinicians.

  9. De stille elever

    DEFF Research Database (Denmark)

    Winther-Lindqvist, Ditte Alexandra

    2012-01-01

    Det er blevet en afgørende samværskompetence i uddannelsessystemet at stå aktivt frem og deltage verbalt i skoleklassens liv både fagligt og socialt. Men ikke alle elever deltager lige villigt verbalt i plenum. Artiklen handler om de stille elever og konsekvenserne af stillehed i skolen. Det...... foreslås at skolesystemet sanktionerer ældre elever hårdere for stillehed end yngre elever og det forklares med at skolelivet også er en kultivering henimod elevhed som social identitet og denne er der forventning om at eleverne mestrer i udskolingen....

  10. Undervisning af tosprogede elever

    DEFF Research Database (Denmark)

    Horst, Christian

    2003-01-01

    Artiklen fremdrager hovedresultaterne fra Virginia P. Collier's og Wayne P. Thomas's længdeundersøgelser af tosprogede elever i USA, som formentlig er de mest omfattende undersøgelser af undervisningen af tosprogede elever overhovedet. Resultaterne diskuteres i relation til udviklingen af en...

  11. Delineation of areas having elevated electrical conductivity, orientation and characterization of bedrock fractures, and occurrence of groundwater discharge to surface water at the U.S. Environmental Protection Agency Barite Hill/Nevada Goldfields Superfund site near McCormick, South Carolina

    Science.gov (United States)

    Chapman, Melinda J.; Huffman, Brad A.; McSwain, Kristen Bukowski

    2015-07-16

    During October 2012 through March 2013, the U.S. Geological Survey (USGS), in cooperation with the U.S. Environmental Protection Agency (EPA) Region 4, Superfund Section, conducted borehole geophysical logging, surface geophysical surveys, and water-quality profiling in selected wells and areas to characterize or delineate the extent of elevated subsurface electrical conductivity at the EPA Barite Hill/Nevada Goldfields Superfund site near McCormick, South Carolina. Elevated electrical conductivity measured at the site may be related to native rock materials, waste rock disposal areas used in past operations, and (or) groundwater having elevated dissolved solids (primarily metals and major ions) related to waste migration. Five shallow screened wells and four open-borehole bedrock wells were logged by using a suite of borehole tools, and downhole water-quality profiles were recorded in two additional wells. Well depths ranged from about 26 to 300 feet below land surface. Surface geophysical surveys based on frequency-domain electromagnetic and distributed temperature sensing (DTS) techniques were used to identify areas of elevated electrical conductivity (Earth materials and groundwater) and potential high dissolved solids in groundwater and surface water on land and in areas along the northern unnamed tributary at the site.

  12. Elevators or stairs?

    Science.gov (United States)

    Shah, Sachin; O’Byrne, Michael; Wilson, Merne; Wilson, Thomas

    2011-01-01

    Background: Staff in hospitals frequently travel between floors and choose between taking the stairs or elevator. We compared the time savings with these two options. Methods: Four people aged 26–67 years completed 14 trips ranging from one to six floors, both ascending and descending. We compared the amount of time per floor travelled by stairs and by two banks of elevators. Participants reported their fatigue levels using a modified Borg scale. We performed two-way analysis of variance to compare the log-transformed data, with participant and time of day as independent variables. Results: The mean time taken to travel between each floor was 13.1 (standard deviation [SD] 1.7) seconds by stairs and 37.5 (SD 19.0) and 35.6 (SD 23.1) seconds by the two elevators (F = 8.61, p elevator equaled about 15 minutes a day. Self-reported fatigue was less than 13 (out of 20) on the Borg scale for all participants, and they all stated that they were able to continue their duties without resting. The extra time associated with elevator use was because of waiting for its arrival. There was a difference in the amount of time taken to travel by elevator depending on the time of day and day of the week. Interpretation: Taking the stairs rather than the elevator saved about 15 minutes each workday. This 3% savings per workday could translate into improved productivity as well as increased fitness. PMID:22159365

  13. Geared-elevator flutter study. [transonic flutter characteristics of empennage

    Science.gov (United States)

    Ruhlin, C. L.; Doggett, R. V., Jr.; Gregory, R. A.

    1976-01-01

    The paper describes an experimental and analytical study of the transonic flutter characteristics of an empennage flutter model having an all-movable horizontal tail with a geared elevator. Two configurations were flutter tested: one with a geared elevator and one with a locked elevator with the model cantilever-mounted on a sting in the wind tunnel. The geared-elevator configuration fluttered experimentally at about 20% higher dynamic pressures than the locked-elevator configuration. The experimental flutter boundary was nearly flat at transonic speeds for both configurations. It was found that an analysis which treated the elevator as a discrete surface predicted flutter dynamic pressure levels better than analyses which treated the stabilizer and elevator as a warped surface. Warped-surface methods, however, predicted more closely the experimental flutter frequencies and Mach number trends.

  14. Photoreflectance at elevated temperatures

    Science.gov (United States)

    Shen, Hongen

    1990-08-01

    Using the contactiess modulation spectroscopy technique of photoreflectance, the temperature variations of the direct gap E0 of GaAs, InP, GaA1As, InGaAs have been measured at elevated temperatures up to 600°C. The parameters which describe the temperature dependence of the band gap energies have been evaluated. The ability to measure the band gap at elevated temperatures opens up many new possibilities for in-situ monitoring of MBE and MOCVD processes. In this paper, we review some of the recent developments in the use of photoreflectance at elevated temperatures.

  15. Design of a powered elevator control system. [powered elevator system for modified C-8A aircraft for STOL operation

    Science.gov (United States)

    Glende, W. L. B.

    1974-01-01

    The design, fabrication and flight testing of a powered elevator system for the Augmentor Wing Jet STOL Research Aircraft (AWJSRA or Mod C-8A) are discussed. The system replaces a manual spring tab elevator control system that was unsatisfactory in the STOL flight regime. Pitch control in the AWJSRA is by means of a single elevator control surface. The elevator is used for both maneuver and trim control as the stabilizer is fixed. A fully powered, irreversible flight control system powered by dual hydraulic sources was designed. The existing control columns and single mechanical cable system of the AWJSRA have been retained as has been the basic elevator surface, except that the elevator spring tab is modified into a geared balance tab. The control surface is directly actuated by a dual tandem moving body actuator. Control signals are transmitted from the elevator aft quadrant to the actuator by a linkage system that includes a limited authority series servo actuator.

  16. Indsatser for tosprogede elever

    DEFF Research Database (Denmark)

    Andersen, Dines; Jakobsen, Vibeke; Jensen, Vibeke Myrup

    Fagligt set klarer tosprogede elever sig dårligere i skolen og det videre uddannelsessystem end ’danske’ elever. Kommuner og folkeskoler har derfor sat en række tiltag i værk, som sigter mod at forbedre de tosprogede elevers skole- og uddannelsessituation. Rapporten kortlægger og analyserer...... af klasseundervisningen. Analysen viser, at de elever, der bliver taget ud af klassen for at få ekstra undervisning i dansk som andetsprog, klarer sig dårligere end elever, der modtager ekstraundervisningen i klassen eller uden for skoletid. Undersøgelsen er baseret på spørgeskemaundersøgelser blandt...... kommunale forvaltningschefer, skoleledere, lærere og forældre til børn i 2. klasse samt lærere til og elever i 9. klasse, SFI’s forløbsundersøgelse af årgang 1995 og registerdata. Undersøgelsen er via Ministeriet for Børn og Undervisning betalt med midler fra satspuljeaftalen 2009 om integration....

  17. Digital elevation modeling via curvature interpolation for lidar data

    Science.gov (United States)

    Digital elevation model (DEM) is a three-dimensional (3D) representation of a terrain's surface - for a planet (including Earth), moon, or asteroid - created from point cloud data which measure terrain elevation. Its modeling requires surface reconstruction for the scattered data, which is an ill-p...

  18. Interaktive tavler - interaktive elever

    DEFF Research Database (Denmark)

    Reusch, Charlotte; Otzen, Elsebeth

    Abstract, Poster-præsentation 13.-14. juni 2012, Pilotprojekt: Interaktive tavler ? interaktive elever Lektor, cand. pæd., Elsebeth Otzen og Lektor, cand. mag., Charlotte Reusch, Institut for Skole og Læring, Læreruddannelsen, Professionshøjskolen Metropol, København Hvordan motiverer en interaktiv...... tavle lærere og elever? Hvad sker der mellem elev, stof og lærer, når læreren bliver i stand til at billedliggøre og dynamisere sine oplæg på tavlen? Bliver læreroplæg prioriteret? Bliver eleverne aktive, eller ender den interaktive tavle med blot at understøtte lærerens envejskommunikation til klassen......? Og hvad sker der mellem eleverne? Disse spørgsmål var igangsættende for arbejdet med pilotprojektet Interaktive tavler ? interaktive elever, som blev afviklet i skoleåret 2010-2011. Projektet blev udført af en tværfaglig gruppe, bestående af lektorer i matematik, biologi og dansk i læreruddannelsen...

  19. Udeskole og elevers handlekompetence

    DEFF Research Database (Denmark)

    Breiting, Søren

    2011-01-01

    Elever elsker at komme væk fra undervisningen i skolen. Er det positivt eller negativt? Og hvad har betydning for, at eleverne får mest muligt ud af oplevelserne uden for skolen? Forskellige former for udeskole giver nogle oplagte muligheder, så eleverne udvikler sig som engagerede borgere i et...

  20. Interaktive tavler - interaktive elever

    DEFF Research Database (Denmark)

    Reusch, Charlotte F.; Otzen, Elsebeth

    Abstract, Poster-præsentation 13.-14. juni 2012, Pilotprojekt: Interaktive tavler – interaktive elever Lektor, cand. pæd., Elsebeth Otzen og Lektor, cand. mag., Charlotte Reusch, Institut for Skole og Læring, Læreruddannelsen, Professionshøjskolen Metropol, København Hvordan motiverer en interaktiv...... tavle lærere og elever? Hvad sker der mellem elev, stof og lærer, når læreren bliver i stand til at billedliggøre og dynamisere sine oplæg på tavlen? Bliver læreroplæg prioriteret? Bliver eleverne aktive, eller ender den interaktive tavle med blot at understøtte lærerens envejskommunikation til klassen......? Og hvad sker der mellem eleverne? Disse spørgsmål var igangsættende for arbejdet med pilotprojektet Interaktive tavler – interaktive elever, som blev afviklet i skoleåret 2010-2011. Projektet blev udført af en tværfaglig gruppe, bestående af lektorer i matematik, biologi og dansk i læreruddannelsen...

  1. Influence of elevated CO

    NARCIS (Netherlands)

    Annibale, D' Alessandra; Larsen, Thomas; Sechi, Valentina; Cortet, Jérôme; Strandberg, Beate; Vincze, Éva; Filser, Juliane; Audisio, Paolo Aldo; Krogh, Paul Henning

    2015-01-01

    We hypothesized that the combined effect of rising levels of atmospheric carbon dioxide (CO2) and increasing use of genetically modified (GM) crops in agriculture may affect soil food-webs. So we designed a study for the assessment of the effects of elevated CO2

  2. Estimating Coastal Digital Elevation Model (DEM) Uncertainty

    Science.gov (United States)

    Amante, C.; Mesick, S.

    2017-12-01

    Integrated bathymetric-topographic digital elevation models (DEMs) are representations of the Earth's solid surface and are fundamental to the modeling of coastal processes, including tsunami, storm surge, and sea-level rise inundation. Deviations in elevation values from the actual seabed or land surface constitute errors in DEMs, which originate from numerous sources, including: (i) the source elevation measurements (e.g., multibeam sonar, lidar), (ii) the interpolative gridding technique (e.g., spline, kriging) used to estimate elevations in areas unconstrained by source measurements, and (iii) the datum transformation used to convert bathymetric and topographic data to common vertical reference systems. The magnitude and spatial distribution of the errors from these sources are typically unknown, and the lack of knowledge regarding these errors represents the vertical uncertainty in the DEM. The National Oceanic and Atmospheric Administration (NOAA) National Centers for Environmental Information (NCEI) has developed DEMs for more than 200 coastal communities. This study presents a methodology developed at NOAA NCEI to derive accompanying uncertainty surfaces that estimate DEM errors at the individual cell-level. The development of high-resolution (1/9th arc-second), integrated bathymetric-topographic DEMs along the southwest coast of Florida serves as the case study for deriving uncertainty surfaces. The estimated uncertainty can then be propagated into the modeling of coastal processes that utilize DEMs. Incorporating the uncertainty produces more reliable modeling results, and in turn, better-informed coastal management decisions.

  3. Skuldertesten "Kombineret Elevation"

    DEFF Research Database (Denmark)

    Clausen, Mikkel Bek; Overkær, Brian

    2010-01-01

    Formål: At udarbejde en testprotokol for testen Kombineret Elevation (KE) og undersøge test-retest variationen ved test af elite svømmere, samt diskutere testens relevans og validitet. Materiale og Metode: 9 elite og 10 sub-elite svømmere, heraf var 11 mænd og 8 kvinder, gennemførte testen KE 2...

  4. Fish elevator and method of elevating fish

    Science.gov (United States)

    Truebe, Jonathan; Drooker, Michael S.

    1984-01-01

    A means and method for transporting fish from a lower body of water to a higher body of water. The means comprises a tubular lock with a gated entrance below the level of the lower body of water through which fish may enter the lock and a discharge passage above the level of the upper body of water. The fish raising means in the lock is a crowder pulled upward by a surface float as water from the upper body of water gravitationally flows into the closed lock filling it to the level of the upper body. Water is then pumped into the lock to raise the level to the discharge passage. The crowder is then caused to float upward the remaining distance through the water to the level of the discharge passage by the introduction of air into a pocket on the underside of the crowder. The fish are then automatically discharged from the lock into the discharge passage by the out of water position of the crowder. The movement of the fish into the discharge passage is aided by the continuous overflow of water still being pumped into the lock. A pipe may be connected to the discharge passage to deliver the fish to a selected location in the upper body of water.

  5. A new bed elevation dataset for Greenland

    Directory of Open Access Journals (Sweden)

    J. L. Bamber

    2013-03-01

    Full Text Available We present a new bed elevation dataset for Greenland derived from a combination of multiple airborne ice thickness surveys undertaken between the 1970s and 2012. Around 420 000 line kilometres of airborne data were used, with roughly 70% of this having been collected since the year 2000, when the last comprehensive compilation was undertaken. The airborne data were combined with satellite-derived elevations for non-glaciated terrain to produce a consistent bed digital elevation model (DEM over the entire island including across the glaciated–ice free boundary. The DEM was extended to the continental margin with the aid of bathymetric data, primarily from a compilation for the Arctic. Ice thickness was determined where an ice shelf exists from a combination of surface elevation and radar soundings. The across-track spacing between flight lines warranted interpolation at 1 km postings for significant sectors of the ice sheet. Grids of ice surface elevation, error estimates for the DEM, ice thickness and data sampling density were also produced alongside a mask of land/ocean/grounded ice/floating ice. Errors in bed elevation range from a minimum of ±10 m to about ±300 m, as a function of distance from an observation and local topographic variability. A comparison with the compilation published in 2001 highlights the improvement in resolution afforded by the new datasets, particularly along the ice sheet margin, where ice velocity is highest and changes in ice dynamics most marked. We estimate that the volume of ice included in our land-ice mask would raise mean sea level by 7.36 m, excluding any solid earth effects that would take place during ice sheet decay.

  6. Elevation data for floodplain mapping

    National Research Council Canada - National Science Library

    Committee on Floodplain Mapping Technologies; National Research Council; Division on Earth and Life Studies; National Research Council

    2007-01-01

    .... Elevation Data for Floodplain Mapping shows that there is sufficient two-dimensional base map imagery to meet FEMA's flood map modernization goals, but that the three-dimensional base elevation data...

  7. Epithelial integrity in palatal shelf elevation

    Directory of Open Access Journals (Sweden)

    Shigeru Okuhara

    2012-02-01

    Full Text Available The palate is the ceiling of the oral cavity that separates the nasal and oral cavities in mammals. Anterior two-thirds of the palate that has the bone and the rugae on the oral surface is the hard palate, and the posterior one-third of the palate lacks bone and is referred to as the soft palate. Palate development involves a sequential process of outgrowth, elevation, and fusion of palatal shelves. When these steps are interrupted or compromised, cleft palate, one of the most frequent human congenital anomalies, develops. In particular, during the elevation process, sufficient proliferation of palatal mesenchymal cells and concomitant synthesis of extracellular matrix (ECM are required, and these are referred to as intrinsic factors. One of major extrinsic factors for this process is the functional maturation of masticatory muscles that are responsible for movement of the mandible and lingual muscles, such that the tongue can descend and sufficient space for shelf elevation is provided. In addition to these factors, recent findings have suggested that a third factor, epithelial integrity, may be an essential component for successful shelf elevation. For example, disruption of epithelial integrity can result in ectopic epithelial fusion between the palate and the mandible, or tongue, which anchors the palatal shelf to inhibit its elevation. Although most histological and molecular aspects of palatal elevation have been well reviewed, those of epithelial integrity have not been thoroughly elucidated. Therefore, in this review, features of epithelial integrity, and its contributing molecules, are described in relation to palatal shelf elevation in mice.

  8. GLAS/ICESat L1B Global Elevation Data V034

    Data.gov (United States)

    National Aeronautics and Space Administration — Data granules contain approximately 23 minutes (1/4 orbit) and include the surface elevation, surface roughness assuming no slope, surface slope assuming no...

  9. GLAS/ICESat L1B Global Elevation Data (HDF5) V033

    Data.gov (United States)

    National Aeronautics and Space Administration — Data granules contain approximately 23 minutes (1/4 orbit) and include the surface elevation, surface roughness assuming no slope, surface slope assuming no...

  10. Space Elevator Concept Considered a Reality

    Science.gov (United States)

    2000-01-01

    The `once upon a time' science fiction concept of a space elevator has been envisioned and studied as a real mass transportation system in the latter part of the 21st century. David Smitherman of NASA's Marshall Space Flight Center's Advanced Projects Office has compiled plans for such an elevator. The space elevator concept is a structure extending from the surface of the Earth to geostationary Earth orbit (GEO) at 35,786 km in altitude. The tower would be approximately 50 km tall with a cable tethered to the top. Its center mass would be at GEO such that the entire structure orbits the Earth in sync with the Earth's rotation maintaining a stationary position over its base attachment at the equator. Electromagnetic vehicles traveling along the cable could serve as a mass transportation system for transporting people, payloads, and power between space and Earth. This illustration by artist Pat Rawling shows the concept of a space elevator as viewed from the geostationary transfer station looking down the length of the elevator towards the Earth.

  11. Elevator buttons as unrecognized sources of bacterial colonization in hospitals.

    Science.gov (United States)

    Kandel, Christopher E; Simor, Andrew E; Redelmeier, Donald A

    2014-01-01

    Elevators are ubiquitous and active inside hospitals, potentially facilitating bacterial transmission. The objective of this study was to estimate the prevalence of bacterial colonization on elevator buttons in large urban teaching hospitals. A total of 120 elevator buttons and 96 toilet surfaces were swabbed over separate intervals at 3 tertiary care hospitals on weekdays and weekends in Toronto, Ontario. For the elevators, swabs were taken from 2 interior buttons (buttons for the ground floor and one randomly selected upper-level floor) and 2 exterior buttons (the "up" button from the ground floor and the "down" button from the upper-level floor). For the toilet surfaces, swabs were taken from the exterior and interior handles of the entry door, the privacy latch, and the toilet flusher. Samples were obtained using standard bacterial collection techniques, followed by plating, culture, and species identification by a technician blind to sample source. The prevalence of colonization of elevator buttons was 61% (95% confidence interval 52%-70%). No significant differences in colonization prevalence were apparent in relation to location of the buttons, day of the week, or panel position within the elevator. Coagulase-negative staphylococci were the most common organisms cultured, whereas Enterococcus and Pseudomonas species were infrequent. Elevator buttons had a higher prevalence of colonization than toilet surfaces (61% v. 43%, p = 0.008). Hospital elevator buttons were commonly colonized by bacteria, although most pathogens were not clinically relevant. The risk of pathogen transmission might be reduced by simple countermeasures.

  12. Lærer-elev-relationer

    DEFF Research Database (Denmark)

    Laursen, Per Fibæk; Nielsen, Anne Maj

    2015-01-01

    I kapitlet belyser vi relationskompetence i forholdet mellem lærer og elever og hvordan læreren kan arbejde med forhold til elever og med sin opmærksomhed på relationsarbejdet. Afslutningsvis ser vi på hvordan lærere fortsat kan udvikle deres relationskompetence.......I kapitlet belyser vi relationskompetence i forholdet mellem lærer og elever og hvordan læreren kan arbejde med forhold til elever og med sin opmærksomhed på relationsarbejdet. Afslutningsvis ser vi på hvordan lærere fortsat kan udvikle deres relationskompetence....

  13. Success and Failure Rates of 1,344 6- to 9-mm-Length Rough-Surface Implants Placed at the Time of Transalveolar Sinus Elevations, Restored with Single Crowns, and Followed for 60 to 229 Months in Function.

    Science.gov (United States)

    Fugazzotto, Paul A

    To assess the success and stability of 6-, 7-, 8-, and 9-mm-long, 6.5-mm-wide-neck tissue-level implants placed at the time of transalveolar sinus augmentation therapy, utilizing a trephine and osteotome approach, which were restored with single crowns. In total, 1,344 implants were placed by the author, varying in length from 6 to 9 mm, with parallel-wall 4.8-mm-diameter implant bodies and 6.5-mm-diameter implant necks. The implants were restored with single abutments and crowns by a variety of practitioners. They were followed for 60 to 229 months in function, with a mean time of 121.1 months in function. Implant success was evaluated by the author utilizing a combination of the Albrektsson et al criteria, and buccal and palatal/lingual bone sounding under anesthesia. The overall cumulative success rate was 98.8%. One hundred ninety 6-mm-long implants demonstrated a cumulative success rate of 97.5% at a mean time of 109.2 months in function. Eleven 7-mm-long implants demonstrated a cumulative success rate of 100% at a mean time of 218.5 months in function. One thousand ninety-four 8-mm-long implants demonstrated a cumulative success rate of 98.9% at a mean time of 112.3 months in function. Forty-nine 9-mm-long implants demonstrated a cumulative success rate of 100% at a mean time of 212.1 months in function. Implants of 6 to 9 mm in length, placed at the time of trephine and osteotome transalveolar sinus elevation procedures and restored with abutments and single crowns, demonstrate a high level of long-term clinical success, assuming specific comprehensive treatment criteria are met.

  14. Elevation of the diaphragmatic cupola

    International Nuclear Information System (INIS)

    Semenov, V.M.; Talesnik, M.R.

    1988-01-01

    Altogether 45 patients with elevation of the diaphragmatic cupola were examined. A high frequency of erroneous initial interpretation of examination results was noted in inflammatory and tumorous lesions and congenital conditions. Routine and contrast methods (pneumoperitoneum, bronchography, pleurography and fistulography) were used. Disease-related methods of X-ray investigation were proposed. A variety of causes of diaphragm elevation was indicated

  15. Rotating Space Elevators: Classical and Statistical Mechanics

    Science.gov (United States)

    Knudsen, Steven

    We investigate a novel and unique dynamical system, the Rotating Space Elevator (RSE). The RSE is a multiply rotating system of strings reaching beyond the Earth geo-synchronous satellite orbit. Objects sliding along the RSE string ("climbers") do not require internal engines or propulsion to be transported far away from the Earth's surface. The RSE thus solves a major problem in the space elevator technology which is how to supply the energy to the climbers moving along the string. The RSE is a double rotating floppy string. The RSE can be made in various shapes that are stabilized by an approximate equilibrium between the gravitational and inertial forces acting in the double rotating frame. The RSE exhibits a variety of interesting dynamical phenomena studied in this thesis.

  16. Space Station tethered elevator system

    Science.gov (United States)

    Haddock, Michael H.; Anderson, Loren A.; Hosterman, K.; Decresie, E.; Miranda, P.; Hamilton, R.

    1989-01-01

    The optimized conceptual engineering design of a space station tethered elevator is presented. The tethered elevator is an unmanned, mobile structure which operates on a ten-kilometer tether spanning the distance between Space Station Freedom and a platform. Its capabilities include providing access to residual gravity levels, remote servicing, and transportation to any point along a tether. The report discusses the potential uses, parameters, and evolution of the spacecraft design. Emphasis is placed on the elevator's structural configuration and three major subsystem designs. First, the design of elevator robotics used to aid in elevator operations and tethered experimentation is presented. Second, the design of drive mechanisms used to propel the vehicle is discussed. Third, the design of an onboard self-sufficient power generation and transmission system is addressed.

  17. Optimal Electrostatic Space Tower (Mast, New Space Elevator)

    OpenAIRE

    Bolonkin, Alexander

    2007-01-01

    Author offers and researched the new and revolutionary inflatable electrostatic AB space towers (mast, new space elevator) up to one hundred twenty thousands kilometers (or more) in height. The main innovation is filling the tower by electron gas, which can create pressure up one atmosphere, has negligible small weight and surprising properties. The suggested mast has following advantages in comparison with conventional space elevator: 1. Electrostatic AB tower may be built from Earth surface...

  18. The National Map seamless digital elevation model specifications

    Science.gov (United States)

    Archuleta, Christy-Ann M.; Constance, Eric W.; Arundel, Samantha T.; Lowe, Amanda J.; Mantey, Kimberly S.; Phillips, Lori A.

    2017-08-02

    This specification documents the requirements and standards used to produce the seamless elevation layers for The National Map of the United States. Seamless elevation data are available for the conterminous United States, Hawaii, Alaska, and the U.S. territories, in three different resolutions—1/3-arc-second, 1-arc-second, and 2-arc-second. These specifications include requirements and standards information about source data requirements, spatial reference system, distribution tiling schemes, horizontal resolution, vertical accuracy, digital elevation model surface treatment, georeferencing, data source and tile dates, distribution and supporting file formats, void areas, metadata, spatial metadata, and quality assurance and control.

  19. Elevation Derivatives for Mojave Desert Tortoise Habitat

    Science.gov (United States)

    Wallace, Cynthia S.A.; Gass, Leila

    2008-01-01

    This report describes the methods used to derive various elevation-derivative grids that were inputted to the Mojave Desert Tortoise Habitat model (L. Gass and others, unpub. data). These grids, which capture information on surface roughness and topographic characteristics, are a subset of the environmental datasets evaluated for the tortoise habitat model. This habitat model is of major importance to the U.S. Fish and Wildlife Service, which is charged with management of this threatened population, including relocating displaced tortoises to areas identified as suitable habitat.

  20. Critical Technologies for the Development of Future Space Elevator Systems

    Science.gov (United States)

    Smitherman, David V., Jr.

    2005-01-01

    A space elevator is a tether structure extending through geosynchronous earth orbit (GEO) to the surface of the earth. Its center of mass is in GEO such that it orbits the earth in sync with the earth s rotation. In 2004 and 2005, the NASA Marshall Space Flight Center and the Institute for Scientific Research, Inc. worked under a cooperative agreement to research the feasibility of space elevator systems, and to advance the critical technologies required for the future development of space elevators for earth to orbit transportation. The discovery of carbon nanotubes in the early 1990's was the first indication that it might be possible to develop materials strong enough to make space elevator construction feasible. This report presents an overview of some of the latest NASA sponsored research on space elevator design, and the systems and materials that will be required to make space elevator construction possible. In conclusion, the most critical technology for earth-based space elevators is the successful development of ultra high strength carbon nanotube reinforced composites for ribbon construction in the 1OOGPa range. In addition, many intermediate technology goals and demonstration missions for the space elevator can provide significant advancements to other spaceflight and terrestrial applications.

  1. Base Flood Elevation (BFE) Lines

    Data.gov (United States)

    Department of Homeland Security — The Base Flood Elevation (BFE) table is required for any digital data where BFE lines will be shown on the corresponding Flood Insurance Rate Map (FIRM). Normally if...

  2. Elevated Fixed Platform Test Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Elevated Fixed Platform (EFP) is a helicopter recovery test facility located at Lakehurst, NJ. It consists of a 60 by 85 foot steel and concrete deck built atop...

  3. FEMA DFIRM Base Flood Elevations

    Data.gov (United States)

    Minnesota Department of Natural Resources — The Base Flood Elevation (BFE) table is required for any digital data where BFE lines will be shown on the corresponding Flood Insurance Rate Map (FIRM). Normally,...

  4. Coastal Digital Elevation Models (DEMs)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Digital elevation models (DEMs) of U.S. and other coasts that typically integrate ocean bathymetry and land topography. The DEMs support NOAA's mission to understand...

  5. Troponin elevation in subarachnoid hemorrhage

    OpenAIRE

    Ioannis N. Mavridis; Maria Meliou; Efstratios-Stylianos Pyrgelis

    2015-01-01

    Troponin (tr) elevation in aneurysmal subarachnoid hemorrhage (SAH) patients is often difficult to be appropriately assessed by clinicians, causing even disagreements regarding its management between neurosurgeons and cardiologists. The purpose of this article was to review the literature regarding the clinical interpretation of tr elevation in SAH. We searched for articles in PubMed using the key words: “troponin elevation” and “subarachnoid hemorrhage”. All of them, as well as relative neur...

  6. ICESat: Ice, Cloud and Land Elevation Satellite

    Science.gov (United States)

    Zwally, Jay; Shuman, Christopher

    2002-01-01

    Ice exists in the natural environment in many forms. The Earth dynamic ice features shows that at high elevations and/or high latitudes,snow that falls to the ground can gradually build up tu form thick consolidated ice masses called glaciers. Glaciers flow downhill under the force of gravity and can extend into areas that are too warm to support year-round snow cover. The snow line, called the equilibrium line on a glacier or ice sheet, separates the ice areas that melt on the surface and become show free in summer (net ablation zone) from the ice area that remain snow covered during the entire year (net accumulation zone). Snow near the surface of a glacier that is gradually being compressed into solid ice is called firm.

  7. Historie i spillefilm - for elever

    DEFF Research Database (Denmark)

    Tønnesen, Lone Guldbrandt

    2016-01-01

    MOOC om historiebrug i spillefilm, hvor elever kan lære om, hvordan spillefilm bruger fortiden, og om hvordan vores opfattelse af historien både sætter sig spor i filmene og bliver påvirket af dem.......MOOC om historiebrug i spillefilm, hvor elever kan lære om, hvordan spillefilm bruger fortiden, og om hvordan vores opfattelse af historien både sætter sig spor i filmene og bliver påvirket af dem....

  8. Tether Elevator Crawler Systems (TECS)

    Science.gov (United States)

    Swenson, Frank R.

    1987-01-01

    One of the needs of the experimenters on the space station is access to steady and controlled-variation microgravity environments. A method of providing these environments is to place the experiment on a tether attached to the space station. This provides a high degree of isolation from structural oscillations and vibrations. Crawlers can move these experiments along the tethers to preferred locations, much like an elevator. This report describes the motion control laws developed for these crawlers and the testing of laboratory models of these tether elevator crawlers.

  9. Comparison of AltiKa and CryoSat-2 Elevation and Elevation Rates over the Amundsen Sea Sector

    Science.gov (United States)

    Otosaka, I.; Shepherd, A.; Hogg, A.

    2017-12-01

    Altimeters have been successfully used for more than two decades to observe changes in the ice sheet surface and to estimate the contribution of ice sheets to sea level rise. The Satellite for Argos and AltiKa (SARAL) was launched in February 2013 as a joint mission between the French space agency (CNES) and the Indian Space Research Organisation (ISRO). While the altimeters previously launched into space are operating at Ku-band (13.6 GHz), the altimeter on board SARAL, AltiKa, is the first instrument to operate at Ka-band (36.8 GHz). The higher frequency of AltiKa is expected to lead to reduced penetration of the radar signal into the snowpack, compared to Ku-band. A comparison of ice sheet elevation measurements recorded at the two frequencies may therefore provide useful information on surface and its scattering properties. In this study, we compare elevation and elevation rates recorded by AltiKa and CryoSat-2 between March 2013 and April 2017 over the Amundsen Sea Sector (ASS), one of the most rapidly changing sectors of West Antarctica. Elevation and elevation rates are computed within 5 km grid cells using a plane fit method, taking into account the contributions of topography and fluctuations in elevation and backscatter. The drifting orbit and imaging modes of CryoSat-2 result in 78,7 % sampling of the study area, whereas AltiKa samples 39,7 % due to its sparser orbit pattern and due to loss of signal in steeply sloping coastal margins. Over the study period, the root mean square difference between elevation and elevation change recorded at Ka-band and Ku-band were 40.3 m and 0.54 m/yr, respectively. While the broad spatial pattern of elevation change is well resolved by both satellites, data gaps along the Getz coastline may be partly responsible for the lower elevation change rate observed at Ka-band. We also compared CryoSat-2 and AltiKa to coincident airborne data from NASA's Operation IceBridge (OIB). The mean difference of elevation rate between

  10. Methylphenidatinduceret ST-elevations-myokardieinfarkt

    DEFF Research Database (Denmark)

    Ruwald, Martin Huth; Ruwald, Anne-Christine Huth; Tønder, Niels

    2012-01-01

    Adult attention deficit and hyperkinetic disorder (ADHD) is increasingly diagnosed and treated with methylphenidate. We present the case of an 20 year-old man, who was diagnosed with ADHD and suffered a ST elevation acute myocardial infarction due to coronary vasospasm related to an overdose...

  11. Dannelsen af den ansvarlige elev

    DEFF Research Database (Denmark)

    Larsen, Jesper

    2010-01-01

    Denne artikel handler om den del af lærergerningen, der har at gøre med udarbejdelse af elevplaner. Der tages udgangspunkt i en foucaultsk forståelse, hvor beskrivelsen af den enkelte elev udtrykker et særligt normativt ideal om, hvilke former for elevhed der er de ønskværdige i den danske...

  12. Air temperature variability in a high-elevation Himalayan catchment

    NARCIS (Netherlands)

    Heynen, Martin; Miles, Evan; Ragettli, Silvan; Buri, Pascal; Immerzeel, Walter W.; Pellicciotti, Francesca

    2016-01-01

    Air temperature is a key control of processes affecting snow and glaciers in high-elevation catchments, including melt, snowfall and sublimation. It is therefore a key input variable to models of land-surface-atmosphere interaction. Despite this importance, its spatial variability is poorly

  13. 46 CFR 120.540 - Elevators.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Elevators. 120.540 Section 120.540 Shipping COAST GUARD... Requirements § 120.540 Elevators. Each elevator on a vessel must meet the requirements of American National Standards Institute (ANSI) A17.1. “Safety Code for Elevators, and Escalators,” or other standard specified...

  14. Space Colonization Using Space-Elevators from Phobos

    Science.gov (United States)

    Weinstein, Leonard M.

    2003-01-01

    A novel approach is examined for creating an industrial civilization beyond Earth. The approach would take advantage of the unique configuration of Mars and its moon Phobos to make a transportation system capable of raising mass from the surface of Mars to space at a low cost. Mars would be used as the primary location for support personnel and infrastructure. Phobos would be used as a source of raw materials for space-based activity, and as an anchor for tethered carbon-nanotube-based space-elevators. One space-elevator would terminate at the upper edge of Mars' atmosphere. Small craft would be launched from Mars' surface to rendezvous with the moving elevator tip and their payloads detached and raised with solar powered loop elevators to Phobos. Another space-elevator would be extended outward from Phobos to launch craft toward the Earth/Moon system or the asteroid belt. The outward tip would also be used to catch arriving craft. This approach would allow Mars to be colonized, and allow transportation of people and supplies from Mars to support the space industry. In addition, large quantities of material obtained from Phobos could be used to construct space habitats and also supply propellant and material for space industry in the Earth/Moon system as well as around Mars.

  15. Elevator deflections on the icing process

    Science.gov (United States)

    Britton, Randall K.

    1990-01-01

    The effect of elevator deflection of the horizontal stabilizer for certain icing parameters is investigated. Elevator deflection can severely change the lower and upper leading-edge impingement limits, and ice can accrete on the elevator itself. Also, elevator deflection had practically no effect on the maximum local collection efficiency. It is shown that for severe icing conditions (large water droplets), elevator deflections that increase the projected height of the airfoil can significantly increase the total collection efficiency of the airfoil.

  16. Når elever producerer

    DEFF Research Database (Denmark)

    Bremholm, Jesper; Hansen, Rune; Slot, Marie Falkesgaard

    2017-01-01

    Dette kapitel præsenterer centrale resultater fra studiet Elevopgaver og elevproduktion i det 21. århundrede der blandt andet rummer den første større kvantitative undersøgelse af opgavedidaktik og elevers produktive arbejde i den danske grundskole. Studiet omfatter også en kvalitativ del, og i...... undersøgelsen præsenteres og diskuteres gennem en række konkrete eksempler fra de berørte fag. I forhold til elevers produktive arbejde peger undersøgelsens resultater både på potentialer og særlige barrierer i forbindelse med at udvikle en kompetenceorienteret undervisning. I kapitlet argumenteres desuden...

  17. Læring mellem elever

    DEFF Research Database (Denmark)

    Georgsen, Marianne; Davidsen, Jacob

    2010-01-01

    I denne rapport præsenteres resultater fra følgeforskningen til projektet Læring gennem Bevægelse, som er gennemført på Søndervangskolen i Hammel i perioden august 2009 - maj 2010. Projektet er gennemført i samspil mellem lærere, it-vejleder, elever og skolens ledelse. Projektets overordnede formål...

  18. Pendulum motions of extended lunar space elevator

    Science.gov (United States)

    Burov, A. A.; Kosenko, I. I.

    2014-09-01

    In the usual everyday life, it is well known that the inverted pendulum is unstable and is ready to fall to "all four sides," to the left and to the right, forward and backward. The theoretical studies and the lunar experience of moon robots and astronauts also confirms this property. The question arises: Is this property preserved if the pendulum is "very, very long"? It turns out that the answer is negative; namely, if the pendulum length significantly exceeds the Moon radius, then the radial equilibria at which the pendulum is located along the straight line connecting the Earth and Moon centers are Lyapunov stable and the pendulum does not fall in any direction at all. Moreover, if the pendulum goes beyond the collinear libration points, then it can be extended and manufactured from cables. This property was noted by F. A. Tsander and underlies the so-called lunar space elevator (e.g., see [1]). In the plane of the Earth and Moon orbits, there are some other equilibria which turn out to be unstable. The question is, Are there equilibria at which the pendulum is located outside the orbital plane? In this paper, we show that the answer is positive, but such equilibria are unstable in the secular sense. We also study necessary conditions for the stability of lunar pendulum oscillations in the plane of the lunar orbit. It was numerically discovered that stable and unstable equilibria alternate depending on the oscillation amplitude and the angular velocity of rotation. The study of the lunar elevator dynamics originates in [2]. The concept of lunar elevator was developed in detail in [3, 4]. Several classes of equilibria with the finiteness of the Moon size taken into account were studied in [5]. The possibility of location of an orbital station fixed to the Moon surface by a pair of tethers was investigated in [6]. The problem of orientation of the terminal station of the lunar space elevator was studied in [7]. The influence of the tether length variations on the

  19. How processing digital elevation models can affect simulated water budgets

    Science.gov (United States)

    Kuniansky, E.L.; Lowery, M.A.; Campbell, B.G.

    2009-01-01

    For regional models, the shallow water table surface is often used as a source/sink boundary condition, as model grid scale precludes simulation of the water table aquifer. This approach is appropriate when the water table surface is relatively stationary. Since water table surface maps are not readily available, the elevation of the water table used in model cells is estimated via a two-step process. First, a regression equation is developed using existing land and water table elevations from wells in the area. This equation is then used to predict the water table surface for each model cell using land surface elevation available from digital elevation models (DEM). Two methods of processing DEM for estimating the land surface for each cell are commonly used (value nearest the cell centroid or mean value in the cell). This article demonstrates how these two methods of DEM processing can affect the simulated water budget. For the example presented, approximately 20% more total flow through the aquifer system is simulated if the centroid value rather than the mean value is used. This is due to the one-third greater average ground water gradients associated with the centroid value than the mean value. The results will vary depending on the particular model area topography and cell size. The use of the mean DEM value in each model cell will result in a more conservative water budget and is more appropriate because the model cell water table value should be representative of the entire cell area, not the centroid of the model cell.

  20. Technology Development and Demonstration Concepts for the Space Elevator

    Science.gov (United States)

    Smitherman, David V., Jr.

    2004-01-01

    During the 1990s several discoveries and advances in the development of carbon nano-tube (CNT) materials indicated that material strengths many times greater than common high-strength composite materials might be possible. Progress in the development of this material led to renewed interest in the space elevator concept for construction of a tether structure from the surface of the Earth through a geostationary orbit (GEO) and thus creating a new approach to Earth-to-orbit transportation infrastructures. To investigate this possibility the author, in 1999, managed for NASA a space elevator work:hop at the Marshall Space Flight Center to explore the potential feasibility of space elevators in the 21 century, and to identify the critical technologies and demonstration missions needed to make development of space elevators feasible. Since that time, a NASA Institute for Advanced Concepts (NIAC) funded study of the Space Elevator proposed a concept for a simpler first space elevator system using more near-term technologies. This paper will review some of the latest ideas for space elevator development, the critical technologies required, and some of the ideas proposed for demonstrating the feasibility for full-scale development of an Earth to GEO space elevator. Critical technologies include CNT composite materials, wireless power transmission, orbital object avoidance, and large-scale tether deployment and control systems. Numerous paths for technology demonstrations have been proposed utilizing ground experiments, air structures. LEO missions, the space shuttle, the international Space Station, GEO demonstration missions, demonstrations at the lunar L1 or L2 points, and other locations. In conclusion, this paper finds that the most critical technologies for an Earth to GEO space elevator include CNT composite materials development and object avoidance technologies; that lack of successful development of these technologies need not preclude continued development of

  1. Operation experience with elevated ammonia

    International Nuclear Information System (INIS)

    Vankova, Katerina; Kysela, Jan; Malac, Miroslav; Petrecky, Igor; Svarc, Vladimir

    2011-01-01

    The 10 VVER units in the Czech and Slovak Republics are all in very good water chemistry and radiation condition, yet questions have arisen regarding the optimization of cycle chemistry and improved operation in these units. To address these issues, a comprehensive experimental program for different water chemistries of the primary circuit was carried out at the Rez Nuclear Research Institute, Czech Republic, with the goal of judging the influence of various water chemistries on radiation build-up. Four types of water chemistries were compared: standard VVER water chemistry (in common use), direct hydrogen dosing without ammonia, standard VVER water chemistry with elevated ammonia levels, and zinc dosing to standard VVER water chemistry. The test results showed that the types of water chemistry other than the common one have benefits for the operation of the nuclear power plant (NPP) primary circuit. Operation experience with elevated ammonia at NPP Dukovany Units 3 and 4 is presented which validates the experimental results, demonstrating improved corrosion product volume activity. (orig.)

  2. LiDAR Elevation Data Collection - Putnam County, NY, 2008 (NYSDEC)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Summary of the surface elevation data collection project in Putnam County, NY (NYSDEC) 2008. Products generated include LiDAR point data in LAS Binary format v1.1....

  3. IceBridge ATM L1B Elevation and Return Strength V002

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains spot elevation measurements of Arctic and Antarctic sea ice, and Greenland, Antarctic Peninsula, and West Antarctic region ice surface...

  4. Global variation in elevational diversity patterns.

    Science.gov (United States)

    Guo, Qinfeng; Kelt, Douglas A; Sun, Zhongyu; Liu, Hongxiao; Hu, Liangjun; Ren, Hai; Wen, Jun

    2013-10-25

    While horizontal gradients of biodiversity have been examined extensively in the past, vertical diversity gradients (elevation, water depth) are attracting increasing attention. We compiled data from 443 elevational gradients involving diverse organisms worldwide to investigate how elevational diversity patterns may vary between the Northern and Southern hemispheres and across latitudes. Our results show that most elevational diversity curves are positively skewed (maximum diversity below the middle of the gradient) and the elevation of the peak in diversity increases with the elevation of lower sampling limits and to a lesser extent with upper limit. Mountains with greater elevational extents, and taxonomic groups that are more inclusive, show proportionally more unimodal patterns whereas other ranges and taxa show highly variable gradients. The two hemispheres share some interesting similarities but also remarkable differences, likely reflecting differences in landmass and mountain configurations. Different taxonomic groups exhibit diversity peaks at different elevations, probably reflecting both physical and physiological constraints.

  5. Digtial Elevation Model (DEM) 250K

    Data.gov (United States)

    Kansas Data Access and Support Center — Digital Elevation Model (DEM) is the terminology adopted by the USGS to describe terrain elevation data sets in a digital raster form. The standard DEM consists of a...

  6. Digitial Elevation Model (DEM) 100K

    Data.gov (United States)

    Kansas Data Access and Support Center — Digital Elevation Model (DEM) is the terminology adopted by the USG to describe terrain elevation data sets in a digital raster form. The standard DEM consists of a...

  7. Digital Elevation Model (DEM) 24K

    Data.gov (United States)

    Kansas Data Access and Support Center — Digital Elevation Model (DEM) is the terminology adopted by the USGS to describe terrain elevation data sets in a digital raster form. The standard DEM consists of a...

  8. Seasonal elevational movements of Eastern Olive Sunbird ...

    African Journals Online (AJOL)

    Little is known about the seasonal elevational movements for most tropical avifauna species. Seasonal elevational movements of the Eastern Olive Sunbird Cyanomitra olivacea were studied along an elevational gradient from 600 to 1 500 m above sea level in the Uluguru Mountains, Tanzania, between May 2005 and ...

  9. Elevated Tank Due to Earthquake Even

    Directory of Open Access Journals (Sweden)

    Kotrasová Kamila

    2017-12-01

    Full Text Available Elevated reservoirs are mainly used for storing of variety water. During earthquake activity the fluid exerts impulsive and convective (sloshing effects on the walls and bottom of tank. This paper provides theoretical background for analytical calculating of elevated water tank due to earthquake even and deals with simplified seismic design procedures for elevated tanks.

  10. Global variation in elevational diversity patterns

    Science.gov (United States)

    Qinfeng Guo; Douglas A. Kelt; Zhongyu Sun; Hongxiao Liu; Liangjun Hu; Hai Ren; Jun We

    2013-01-01

    While horizontal gradients of biodiversity have been examined extensively in the past, vertical diversity gradients (elevation, water depth) are attracting increasing attention. We compiled data from 443 elevational gradients involving diverse organisms worldwide to investigate how elevational diversity patterns may vary between the Northern and Southern hemispheres...

  11. 21 CFR 890.3930 - Wheelchair elevator.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Wheelchair elevator. 890.3930 Section 890.3930 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... elevator. (a) Identification. A wheelchair elevator is a motorized lift device intended for medical...

  12. 46 CFR 183.540 - Elevators.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Elevators. 183.540 Section 183.540 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS (UNDER 100 GROSS TONS) ELECTRICAL INSTALLATION Miscellaneous Systems and Requirements § 183.540 Elevators. Each elevator on a vessel must meet...

  13. Rangeland -- Plant responses to elevated CO sub 2

    Energy Technology Data Exchange (ETDEWEB)

    Owensby, C.E.; Coyne, P.I.; Ham, J.M.; Parton, W.; Rice, C.; Auen, L.M.; Adam, N.

    1992-01-01

    Several broad conclusions which can be drawn from the work that was accomplished during the first 3-year phase of the study is described. In prairie ecosystems dominated by C{sub 4} grasses, it is likely that elevated atmospheric CO{sub 2} will increase ecosystem level productivity, with a greater increase in belowground productivity. The increased productivity will primarily result from increased water use efficiency due to the anti-transpirant action of CO{sub 2}. Fumigation chambers are directly confounded with elevated CO{sub 2} effects, in that both reduce evapotranspiration. The reduced evapotranspiration of the fumigation chamber is primarily through reduced wind speeds and reduced radiation. In very dry years, fumigation chamber effects are negligible, but in years with normal precipitation, chamber effects and elevated CO{sub 2} effects are essentially equal with respect to reduced evapotranspiration effects. Increased production under elevated CO{sub 2} results in reduced nitrogen concentration in the herbage and increased fiber concentrations. Consequently, digestibility of the herbage is reduced, and microbial degradation of surface litter and soil organic matter is slowed. On the negative side, ruminant productivity will likely be reduced substantially, but increased carbon storage in the soil may buffer against future rise in atmospheric CO{sub 2}. Tallgrass prairie will not likely change greatly in botanical composition, since the C{sub 4} dominants responded to elevated CO{sub 2} more than the C{sub 3} subdominants.

  14. Genesis of elevated aerosol loading over the Indian region

    Science.gov (United States)

    Prijith, S. S.; Rao, P. V. N.; Mohan, Mannil

    2016-05-01

    Elevated aerosols assume importance as the diabatic heating due to aerosol absorption is more intense at higher altitudes where the atmosphere becomes thinner. Indian region, especially its central and northern latitudes, experiences significant loading of elevated aerosols during pre-monsoon and summer months. Genesis of elevated aerosol loading over Indian region is investigated in the present study, using multi-year satellite observations from Cloud Aerosol Lidar with Orthogonal Polarization (CALIOP) and Moderate Resolution Imaging Spectroradiometer (MODIS) along with reanalysis winds from MERRA. Central India is observed to have prominent aerosols loading at higher altitudes during pre-monsoon season, whereas it is during summer months over north-west India. Further analysis reveals that the elevated aerosols over Indian region in pre-monsoon and summer months are significantly contributed by transported mineral dust from the arid continental regions at west. In addition to the mineral dust advection, aerosols at higher altitudes over Indian region are enriched by strong convection and associated vertical transport of surface level aerosols. Vertical transport of aerosols observed over Indian region during pre-monsoon and summer months is aided by intense convergence at the surface level and divergence at the upper level. Moreover, aerosol source/sink strength estimated using aerosol flux continuity equation show significant aerosol production over central India during pre-monsoon. Strong vertical transport prevails during pre-monsoon uplifts the locally produced aerosols, with considerable anthropogenic fraction, to higher altitudes where their impacts would be more intense.

  15. Study of influence of climber motion on the space elevator dynamics

    OpenAIRE

    A. S. Ledkov; R. S. Pikalov

    2014-01-01

    The operation of launching a payload into orbit by means of a space elevator is considered in this paper. The space elevator is a mechanical system that consists of a tether, a space station, and a climber. The tether connects the surface of the Earth with the space station, which is above the geostationary orbit. The climber lifts the payload to the required altitude. Then it is disconnected from the space elevator and starts free orbital flight. Creation of the space elevator will significa...

  16. Local thermal and structural behavior of concrete at elevated temperatures

    International Nuclear Information System (INIS)

    Gluekler, E.L.

    1979-01-01

    At elevated temperatures, structural responses of surface heated concrete walls are significantly affected by the release of capillary, adsorbed and chemically bound water. Two major phenomena are generally observed: (1) degradation of concrete strength because of the loss of hydraulic bonds in gelatious, hydrated compounds, shrinkage of the cement matrix, increase in porosity and microcracking, and (2) pressurization of concrete pores because of vaporization of water and expansion of gases. Under certain conditions, the combined effects of material degradation and internal pressurization could lead to crack formation parallel to the surface, or spallation. This failure mode has been observed in some experiments, but not consistently. In this paper, a criterion for concrete spallation is described which depends on (1) loading conditions including pore pressures and thermal stresses, and (2) materials characteristics at elevated temperatures. (orig.)

  17. Community and ecosystem responses to elevational gradients

    DEFF Research Database (Denmark)

    Sundqvist, Maja K.; Sanders, Nate; Wardle, David A.

    2013-01-01

    elevational gradients for understanding community and ecosystem responses to global climate change at much larger spatial and temporal scales than is possible through conventional ecological experiments. However, future studies that integrate elevational gradient approaches with experimental manipulations...... will provide powerful information that can improve predictions of climate change impacts within and across ecosystems.......Community structure and ecosystem processes often vary along elevational gradients. Their responses to elevation are commonly driven by changes in temperature, and many community- and ecosystem-level variables therefore frequently respond similarly to elevation across contrasting gradients...

  18. Magnetically levitated space elevator to low-earth orbit

    International Nuclear Information System (INIS)

    Hull, J. R.; Mulcahy, T. M.

    2001-01-01

    The properties of currently available NbTi superconductor and carbon-fiber structural materials enable the possibility of constructing a magnetically levitated space elevator from the earth's surface up to an altitude of(approx) 200 km. The magnetic part of the elevator consists of a long loop of current-carrying NbTi, composed of one length that is attached to the earth's surface in an east-west direction and a levitated-arch portion. The critical current density of NbTi is sufficiently high that these conductors will stably levitate in the earth's magnetic field. The magnetic self-field from the loop increases the levitational force and for some geometries assists levitational stability. The 200-km maximum height of the levitated arch is limited by the allowable stresses of the structural material. The loop is cryogenically cooled with helium, and the system utilizes intermediate pumping and cooling stations along both the ground and the levitated portion of the loop, similar to other large terrestrial cryogenic systems. Mechanically suspended from the basic loop is an elevator structure, upon which mass can be moved between the earth's surface and the top of the loop by a linear electric motor or other mechanical or electrical means. At the top of the loop, vehicles may be accelerated to orbital velocity or higher by rocket motors, electromagnetic propulsion, or hybrid methods

  19. Anisotropic Third-Order Regularization for Sparse Digital Elevation Models

    KAUST Repository

    Lellmann, Jan

    2013-01-01

    We consider the problem of interpolating a surface based on sparse data such as individual points or level lines. We derive interpolators satisfying a list of desirable properties with an emphasis on preserving the geometry and characteristic features of the contours while ensuring smoothness across level lines. We propose an anisotropic third-order model and an efficient method to adaptively estimate both the surface and the anisotropy. Our experiments show that the approach outperforms AMLE and higher-order total variation methods qualitatively and quantitatively on real-world digital elevation data. © 2013 Springer-Verlag.

  20. The space station tethered elevator system

    Science.gov (United States)

    Anderson, Loren A.

    1989-01-01

    The optimized conceptual engineering design of a space station tethered elevator is presented. The elevator is an unmanned mobile structure which operates on a ten kilometer tether spanning the distance between the Space Station and a tethered platform. Elevator capabilities include providing access to residual gravity levels, remote servicing, and transportation to any point along a tether. The potential uses, parameters, and evolution of the spacecraft design are discussed. Engineering development of the tethered elevator is the result of work conducted in the following areas: structural configurations; robotics, drive mechanisms; and power generation and transmission systems. The structural configuration of the elevator is presented. The structure supports, houses, and protects all systems on board the elevator. The implementation of robotics on board the elevator is discussed. Elevator robotics allow for the deployment, retrieval, and manipulation of tethered objects. Robotic manipulators also aid in hooking the elevator on a tether. Critical to the operation of the tethered elevator is the design of its drive mechanisms, which are discussed. Two drivers, located internal to the elevator, propel the vehicle along a tether. These modular components consist of endless toothed belts, shunt-wound motors, regenerative power braking, and computer controlled linear actuators. The designs of self-sufficient power generation and transmission systems are reviewed. Thorough research indicates all components of the elevator will operate under power provided by fuel cells. The fuel cell systems will power the vehicle at seven kilowatts continuously and twelve kilowatts maximally. A set of secondary fuel cells provides redundancy in the unlikely event of a primary system failure. Power storage exists in the form of Nickel-Hydrogen batteries capable of powering the elevator under maximum loads.

  1. Elevational patterns in archaeal diversity on Mt. Fuji.

    Directory of Open Access Journals (Sweden)

    Dharmesh Singh

    Full Text Available Little is known of how archaeal diversity and community ecology behaves along elevational gradients. We chose to study Mount Fuji of Japan as a geologically and topographically uniform mountain system, with a wide range of elevational zones. PCR-amplified soil DNA for the archaeal 16 S rRNA gene was pyrosequenced and taxonomically classified against EzTaxon-e archaeal database. At a bootstrap cut-off of 80%, most of the archaeal sequences were classified into phylum Thaumarchaeota (96% and Euryarchaeota (3.9%, with no sequences classified into other phyla. Archaeal OTU richness and diversity on Fuji showed a pronounced 'peak' in the mid-elevations, around 1500 masl, within the boreal forest zone, compared to the temperate forest zone below and the alpine fell-field and desert zones above. Diversity decreased towards higher elevations followed by a subtle increase at the summit, mainly due to an increase in the relative abundance of the group I.1b of Thaumarchaeota. Archaeal diversity showed a strong positive correlation with soil NH(4(+, K and NO(3(-. Archaeal diversity does not parallel plant diversity, although it does roughly parallel bacterial diversity. Ecological hypotheses to explain the mid diversity bulge on Fuji include intermediate disturbance effects, and the result of mid elevations combining a mosaic of upper and lower slope environments. Our findings show clearly that archaeal soil communities are highly responsive to soil environmental gradients, in terms of both their diversity and community composition. Distinct communities of archaea specific to each elevational zone suggest that many archaea may be quite finely niche-adapted within the range of soil environments. A further interesting finding is the presence of a mesophilic component of archaea at high altitudes on a mountain that is not volcanically active. This emphasizes the importance of microclimate - in this case solar heating of the black volcanic ash surface--for the

  2. Hydrography-driven coarsening of grid digital elevation models

    Science.gov (United States)

    Moretti, G.; Orlandini, S.

    2017-12-01

    A new grid coarsening strategy, denoted as hydrography-driven (HD) coarsening, is developed in the present study. The HD coarsening strategy is designed to retain the essential hydrographic features of surface flow paths observed in high-resolution digital elevation models (DEMs): (1) depressions are filled in the considered high-resolution DEM, (2) the obtained topographic data are used to extract a reference grid network composed of all surface flow paths, (3) the Horton order is assigned to each link of the reference grid network, and (4) within each coarse grid cell, the elevation of the point lying along the highest-order path of the reference grid network and displaying the minimum distance to the cell center is assigned to this coarse grid cell center. The capabilities of the HD coarsening strategy to provide consistent surface flow paths with respect to those observed in high-resolution DEMs are evaluated over a synthetic valley and two real drainage basins located in the Italian Alps and in the Italian Apennines. The HD coarsening is found to yield significantly more accurate surface flow path profiles than the standard nearest neighbor (NN) coarsening. In addition, the proposed strategy is found to reduce drastically the impact of depression-filling procedures in coarsened topographic data. The HD coarsening strategy is therefore advocated for all those cases in which the relief of the extracted drainage network is an important hydrographic feature. The figure below reports DEMs of a synthetic valley and extracted surface flow paths. (a) 10-m grid DEM displaying no depressions and extracted surface flow path (gray line). (b) 1-km grid DEM obtained from NN coarsening. (c) 1-km grid DEM obtained from NN coarsening plus depression-filling and extracted surface flow path (light blue line). (d) 1-km grid DEM obtained from HD coarsening and extracted surface flow path (magenta line).

  3. Elevated CO2 enhances biological contributions to elevation change in coastal wetlands by offsetting stressors associated with sea-level rise

    Science.gov (United States)

    Cherry, J.A.; McKee, K.L.; Grace, J.B.

    2009-01-01

    1. Sea-level rise, one indirect consequence of increasing atmospheric CO2, poses a major challenge to long-term stability of coastal wetlands. An important question is whether direct effects of elevated CO 2 on the capacity of marsh plants to accrete organic material and to maintain surface elevations outweigh indirect negative effects of stressors associated with sea-level rise (salinity and flooding). 2. In this study, we used a mesocosm approach to examine potential direct and indirect effects of atmospheric CO2 concentration, salinity and flooding on elevation change in a brackish marsh community dominated by a C3 species, Schoenoplectus americanus, and a C4 grass, Spartina patens. This experimental design permitted identification of mechanisms and their role in controlling elevation change, and the development of models that can be tested in the field. 3. To test hypotheses related to CO2 and sea-level rise, we used conventional anova procedures in conjunction with structural equation modelling (SEM). SEM explained 78% of the variability in elevation change and showed the direct, positive effect of S. americanus production on elevation. The SEM indicated that C3 plant response was influenced by interactive effects between CO2 and salinity on plant growth, not a direct CO2 fertilization effect. Elevated CO2 ameliorated negative effects of salinity on S. americanus and enhanced biomass contribution to elevation. 4. The positive relationship between S. americanus production and elevation change can be explained by shoot-base expansion under elevated CO 2 conditions, which led to vertical soil displacement. While the response of this species may differ under other environmental conditions, shoot-base expansion and the general contribution of C3 plant production to elevation change may be an important mechanism contributing to soil expansion and elevation gain in other coastal wetlands. 5. Synthesis. Our results revealed previously unrecognized interactions and

  4. Scientific Return of a Lunar Elevator

    OpenAIRE

    Eubanks, T. M.; Radley, C. F.

    2016-01-01

    The concept of a space elevator dates back to Tsilokovsky, but they are not commonly considered in near-term plans for space exploration, perhaps because a terrestrial elevator would not be possible without considerable improvements in tether material. A Lunar Space Elevator (LSE), however, can be built with current technology using commercially available tether polymers. This paper considers missions leading to infrastructure capable of shortening the time, lowering the cost and enhancing th...

  5. Cholecystokinin elevates mouse plasma lipids.

    Directory of Open Access Journals (Sweden)

    Lichun Zhou

    Full Text Available Cholecystokinin (CCK is a peptide hormone that induces bile release into the intestinal lumen which in turn aids in fat digestion and absorption in the intestine. While excretion of bile acids and cholesterol into the feces eliminates cholesterol from the body, this report examined the effect of CCK on increasing plasma cholesterol and triglycerides in mice. Our data demonstrated that intravenous injection of [Thr28, Nle31]-CCK at a dose of 50 ng/kg significantly increased plasma triglyceride and cholesterol levels by 22 and 31%, respectively, in fasting low-density lipoprotein receptor knockout (LDLR(-/- mice. The same dose of [Thr28, Nle31]-CCK induced 6 and 13% increases in plasma triglyceride and cholesterol, respectively, in wild-type mice. However, these particular before and after CCK treatment values did not achieve statistical significance. Oral feeding of olive oil further elevated plasma triglycerides, but did not alter plasma cholesterol levels in CCK-treated mice. The increased plasma cholesterol in CCK-treated mice was distributed in very-low, low and high density lipoproteins (VLDL, LDL and HDL with less of an increase in HDL. Correspondingly, the plasma apolipoprotein (apo B48, B100, apoE and apoAI levels were significantly higher in the CCK-treated mice than in untreated control mice. Ligation of the bile duct, blocking CCK receptors with proglumide or inhibition of Niemann-Pick C1 Like 1 transporter with ezetimibe reduced the hypercholesterolemic effect of [Thr28, Nle31]-CCK in LDLR(-/- mice. These findings suggest that CCK-increased plasma cholesterol and triglycerides as a result of the reabsorption of biliary lipids from the intestine.

  6. Soil nematodes show a mid-elevation diversity maximum and elevational zonation on Mt. Norikura, Japan.

    Science.gov (United States)

    Dong, Ke; Moroenyane, Itumeleng; Tripathi, Binu; Kerfahi, Dorsaf; Takahashi, Koichi; Yamamoto, Naomichi; An, Choa; Cho, Hyunjun; Adams, Jonathan

    2017-06-08

    Little is known about how nematode ecology differs across elevational gradients. We investigated the soil nematode community along a ~2,200 m elevational range on Mt. Norikura, Japan, by sequencing the 18S rRNA gene. As with many other groups of organisms, nematode diversity showed a high correlation with elevation, and a maximum in mid-elevations. While elevation itself, in the context of the mid domain effect, could predict the observed unimodal pattern of soil nematode communities along the elevational gradient, mean annual temperature and soil total nitrogen concentration were the best predictors of diversity. We also found nematode community composition showed strong elevational zonation, indicating that a high degree of ecological specialization that may exist in nematodes in relation to elevation-related environmental gradients and certain nematode OTUs had ranges extending across all elevations, and these generalized OTUs made up a greater proportion of the community at high elevations - such that high elevation nematode OTUs had broader elevational ranges on average, providing an example consistent to Rapoport's elevational hypothesis. This study reveals the potential for using sequencing methods to investigate elevational gradients of small soil organisms, providing a method for rapid investigation of patterns without specialized knowledge in taxonomic identification.

  7. An Automatic System for Elevator Monitoring

    OpenAIRE

    Md. Haidar Sharif; Ibrahim Furkan Ince

    2015-01-01

    An elevator is a conveyor device or transport equipment that moves people or goods between floors or levels or decks of a building, vessel, or other structures. It has become a part and parcel of modern life in developed countries. The number of floors in high buildings, skyscrapers, and towers generate the usage of elevators. If it is simply assumed that each floor has at least two elevators in a thirty-floor building, people call the elevators in each floor even they are already occupied in...

  8. Accuracy Assessment of Open Source Digital Elevation Models

    Directory of Open Access Journals (Sweden)

    Aqeel Abboud Abdul Hassan

    2018-02-01

    Full Text Available Digital Elevation Model is a three-dimensional representation of the earth's surface, which is essential for Geoscience and hydrological implementations. DEM can be created utilizing Photogrammetry techniques, radar interferometry, laser scanning and land surveying. There are some world agencies provide open source digital elevation models which are freely available for all users, such as the National Aeronautics and Space Administration (NASA, Japan Aerospace Exploration Agency’s (JAXA and others. ALOS, SRTM and ASTER are satellite based DEMs which are open source products. The technologies that are used for obtaining raw data and the methods used for its processing and on the other hand the characteristics of natural land and land cover type, these and other factors are the cause of implied errors produced in the digital elevation model which can't be avoided. In this paper, ground control points observed by the differential global positioning system DGPS were used to compare the validation and performance of different satellite based digital elevation models. For validation, standard statistical tests were applied such as Mean Error (ME and Root Mean Square Error (RMSE which showed ALOS DEM had ME and RMSE are -1.262m and 1.988m, while SRTM DEM had ME of -0.782m with RMSE of 2.276m and ASTER DEM had 4.437m and 6.241m, respectively. These outcomes can be very helpful for analysts utilizing such models in different areas of work.

  9. InSAR elevation bias caused by penetration into uniform volumes

    DEFF Research Database (Denmark)

    Dall, Jørgen

    2007-01-01

    Natural media like cold-land ice, vegetation, and dry sand are subject to a substantial penetration at microwave frequencies. For such media, the synthetic aperture radar (SAR) ase center is located below the surface, and consequently, the surface elevation determined with SAR interferometry (In...

  10. National requirements for improved elevation data

    Science.gov (United States)

    Snyder, Gregory I.; Sugarbaker, Larry J.; Jason, Allyson L.; Maune, David F.

    2014-01-01

    This report presents the results of surveys, structured interviews, and workshops conducted to identify key national requirements for improved elevation data for the United States and its territories, including coastlines. Organizations also identified and reported the expected economic benefits that would be realized if their requirements for improved elevation were met (appendixes 1–3). This report describes the data collection methodology and summarizes the findings. Participating organizations included 34 Federal agencies, 50 States and two territories, and a sampling of local governments, tribes, and nongovernmental orgnizations. The nongovernmental organizations included The Nature Conservancy and a sampling of private sector businesses. These data were collected in 2010-2011 as part of the National Enhanced Elevation Assessment (NEEA), a study to identify program alternatives for better meeting the Nation’s elevation data needs. NEEA tasks included the collection of national elevation requirements; analysis of the benefits and costs of meeting these requirements; assessment of emerging elevation technologies, lifecycle data management needs, and costs for managing and distributing a national-scale dataset and derived products; and candidate national elevation program alternatives that balance costs and benefits in meeting the Nation’s elevation requirements. The NEEA was sponsored by the National Digital Elevation Program (NDEP), a government coordination body with the U.S. Geological Survey (USGS) as managing partner that includes the National Geospatial-Intelligence Agency (NGA), the Federal Emergency Management Agency (FEMA), the Natural Resources Conservation Service (NRCS), the U.S. Army Corps of Engineers (USACE), and the National Oceanic and Atmospheric Administration (NOAA), among the more than a dozen agencies and organizations. The term enhanced elevation data as used in this report refers broadly to three-dimensional measurements of land or

  11. Martian particle size based on thermal inertia corrected for elevation-dependent atmospheric properties

    Science.gov (United States)

    Bridges, N. T.

    1993-01-01

    Thermal inertia is commonly used to derive physical properties of the Martian surface. If the surface is composed of loosely consolidated grains, then the thermal conductivity derived from the inertia can theoretically be used to compute the particle size. However, one persistent difficulty associated with the interpretation of thermal inertia and the derivation of particle size from it has been the degree to which atmospheric properties affect both the radiation balance at the surface and the gas conductivity. These factors vary with atmospheric pressure so that derived thermal inertias and particle sizes are a function of elevation. By utilizing currently available thermal models and laboratory information, a fine component thermal inertia map was convolved with digital topography to produce particle size maps of the Martian surface corrected for these elevation-dependent effects. Such an approach is especially applicable for the highest elevations on Mars, where atmospheric back radiation and gas conductivity are low.

  12. 28 CFR 36.404 - Alterations: Elevator exemption.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Alterations: Elevator exemption. 36.404... Alterations: Elevator exemption. (a) This section does not require the installation of an elevator in an... facility has an elevator. ...

  13. Preventing hairline elevation in endoscopic browlifts.

    Science.gov (United States)

    Hamas, R S; Rohrich, R J

    1997-04-01

    An endoscopic-assisted method of brow elevation using galea aponeurosis plication with direct suture fixation is presented. This technique does not elevate the hairline, nor is any skin or scalp resected. Dissection is easy because it is limited to the subgaleal plane of the forehead.

  14. 78 FR 22221 - Proposed Flood Elevation Determinations

    Science.gov (United States)

    2013-04-15

    ... referenced ground [caret] Communities affected elevation ** Elevation in meters (MSL) Effective Modified Pitt... feet above ground. [caret] Mean Sea Level, rounded to the nearest 0.1 meter. \\**\\ BFEs to be changed... inspection at the Department of Public Works, 1500 Beatty Street, Greenville, NC 27834. Unincorporated Areas...

  15. 75 FR 77762 - Final Flood Elevation Determinations

    Science.gov (United States)

    2010-12-14

    ... Flooding source(s) elevation in feet above Communities affected ground [caret] Elevation in meters (MSL..., rounded to the nearest 0.1 meter. ADDRESSES City of Aurora Maps are available for inspection at 15151 East... Arapahoe County Department of Public Works and Development, 10730 West Briarwood Avenue, Centennial, CO...

  16. 75 FR 69892 - Final Flood Elevation Determinations

    Science.gov (United States)

    2010-11-16

    ...: * Elevation in feet (NGVD) + Elevation in feet (NAVD) State City/town/county Source of flooding Location Depth... county +899 City of Norwich, Town boundary. of Greene, Town of North Norwich, Town of Oxford, Town of...). Susquehanna River At the downstream county +965 Town of Afton, Town of boundary. Bainbridge, Village of Afton...

  17. 77 FR 6980 - Final Flood Elevation Determinations

    Science.gov (United States)

    2012-02-10

    ... in feet (NGVD) + Elevation in feet (NAVD) State City/town/county Source of flooding Location Depth in feet above ground [caret] Elevation in meters (MSL) Modified Unincorporated Areas of Nowata County... Bayou An area bounded by the +100 Town of Mayersville, county boundary to the Unincorporated Areas of...

  18. 76 FR 1535 - Final Flood Elevation Determinations

    Science.gov (United States)

    2011-01-11

    ... in feet (NGVD) + Elevation in feet (NAVD) State City/town/county Source of flooding Location Depth in feet above ground [caret] Elevation in meters (MSL) Modified Unincorporated Areas of Poinsett County... with the St. Francis River...... +212 Areas of Poinsett County. Approximately 0.45 mile downstream of...

  19. 77 FR 66737 - Final Flood Elevation Determinations

    Science.gov (United States)

    2012-11-07

    ... follows: * Elevation in feet (NGVD) + Elevation in feet (NAVD) State City/town/county Source of flooding... +43 Town of Kingstree, Unincorporated Areas of Williamsburg County. Approximately 0.3 mile +48... Town of Hemingway, confluence. Unincorporated Areas of Williamsburg County. Approximately 0.3 mile +50...

  20. 75 FR 29253 - Proposed Flood Elevation Determinations

    Science.gov (United States)

    2010-05-25

    ...: * Elevation in feet (NGVD) + Elevation in feet (NAVD) Depth in feet above State City/town/county Source of... +21 Town of Ebro, upstream of the Unincorporated Areas confluence with the of Washington County. East... County, Colorado, and Incorporated Areas Willow Creek At the confluence with None +8,154 Unincorporated...

  1. 75 FR 68710 - Final Flood Elevation Determinations

    Science.gov (United States)

    2010-11-09

    ...: * Elevation in feet (NGVD) + Elevation in feet (NAVD) State City/town/county Source of flooding Location Depth... County, California Docket Nos.: FEMA-B-7762, FEMA-B-7795, and FEMA-B-1053 California Unincorporated Oregon Slough..... City of Montague +2503 Areas of Siskiyou and County. Unincorporated Siskiyou County...

  2. 77 FR 45262 - Final Flood Elevation Determinations

    Science.gov (United States)

    2012-07-31

    ... in feet (NGVD) + Elevation in feet (NAVD) State City/town/county Source of Location Depth in feet flooding above ground [caret] Elevation in meters (MSL) Modified Unincorporated Areas of Solano County... Areas of Solano upstream of the County. McCune Creek confluence. Approximately 930 feet +149 upstream of...

  3. 76 FR 50918 - Final Flood Elevation Determinations

    Science.gov (United States)

    2011-08-17

    ... in feet (NGVD) + Elevation in feet (NAVD) Depth in feet State City/town/county Source of flooding... affected [caret] Elevation in meters (MSL) Modified Jones County, Texas, and Incorporated Areas Docket No.: FEMA-B-1122 Lake Fort Phantom Hill Just downstream of County +1642 City of Abilene, Highway 1082...

  4. 78 FR 10066 - Final Flood Elevation Determinations

    Science.gov (United States)

    2013-02-13

    ... follows: * Elevation in feet (NGVD) + Elevation in feet (NAVD) Depth in feet State City/town/county Source...). Scriba Creek Approximately 0.90 mile +546 Town of Amboy. upstream of County Route 23 (Potter Road.... Town of Palermo Maps are available for inspection at the Palermo Town Municipal Offices, 53 County...

  5. 77 FR 49367 - Final Flood Elevation Determinations

    Science.gov (United States)

    2012-08-16

    ... in feet (NGVD) + Elevation in feet (NAVD) State City/town/county Source of flooding Location Depth in feet above ground [caret] Elevation in meters (MSL) Modified Unincorporated Areas of Chickasaw County... Chickasaw County. (backwater effects feet upstream of from Cedar River). the Cedar River confluence...

  6. 77 FR 49379 - Final Flood Elevation Determinations

    Science.gov (United States)

    2012-08-16

    ... in feet (NGVD) + Elevation in feet (NAVD) State City/town/county Source of flooding Location Depth in feet above ground [caret] Elevation in meters (MSL) Modified Unincorporated Areas of Washington County... of the +35 Areas of railroad. Washington County. Approximately 2.1 miles upstream of the railroad...

  7. 75 FR 43418 - Final Flood Elevation Determinations

    Science.gov (United States)

    2010-07-26

    ... follows: * Elevation in feet (NGVD) + Elevation in feet (NAVD) State City/town/county Source of flooding... +869 Town of Peoria, upstream of Main Street. Unincorporated Areas of Ottawa County. Approximately 1.... Town of Peoria Maps are available for inspection at the Ottawa County Courthouse, 102 East Central...

  8. Insect Population Dynamics in Commercial Grain Elevators

    Science.gov (United States)

    Data were collected in 1998-2002 from wheat stored in commercial grain elevators in south-central Kansas. Storage bins at these elevators had concrete walls and were typically 6-9 m in diameter and 30-35 m tall. A vacuum-probe sampler was used to collect ten 3-kg grain samples in the top 12 m of the...

  9. High elevation white pines educational website

    Science.gov (United States)

    Anna W. Schoettle; Michele Laskowski

    2011-01-01

    The high elevation five-needle white pines are facing numerous challenges ranging from climate change to invasion by a non-native pathogen to escalation of pest outbreaks. This website (http://www.fs.fed.us/rm/highelevationwhitepines/) serves as a primer for managers and the public on the high elevation North American five-needle pines. It presents information on each...

  10. Controlled electropolishing of copper foils at elevated temperature

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Gi Duk; Kim, Young Woo; Moyen, Eric; Keum, Dong Hoon [Department of Energy Science, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Lee, Young Hee [Department of Energy Science, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); IBS Center for Integrated Nanostructure Physics (CINAP), Institute of Basic Science (IBS), Daejeon (Korea, Republic of); Department of Physics, Sungkyunkwan Advanced Institute of Nano-technology (SAINT), Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Baik, Seunghyun [Department of Energy Science, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); School of Mechanical Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); IBS Center for Integrated Nanostructure Physics (CINAP), Institute of Basic Science (IBS), Daejeon (Korea, Republic of); Pribat, Didier, E-mail: didier53@skku.edu [Department of Energy Science, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of)

    2014-07-01

    We have studied the electrochemical polishing of copper foils at elevated temperature, in H{sub 3}PO{sub 4} electrolytes of various concentrations. Atomic force microscopy, surface reflectance measurements as well as optical microscopy and scanning electron microscopy (including electron backscattering diffraction) have been used throughout this study to characterize the surface of the electropolished foils. We have found that copper foils electropolished at 65 °C in 2.17 M H{sub 3}PO{sub 4}, exhibited a lower surface roughness and a higher percent specular reflection, comparing with values obtained after classical electropolishing in concentrated H{sub 3}PO{sub 4} at room temperature or comparing with values obtained after chemical-mechanical polishing. This work could open up new prospects for the preparation of copper foils before the growth of high quality graphene layers.

  11. The benefits of improved national elevation data

    Science.gov (United States)

    Snyder, Gregory I.

    2013-01-01

    This article describes how the National Enhanced Elevation Assessment (NEEA) has identified substantial benefits that could come about if improved elevation data were publicly available for current and emerging applications and business uses such as renewable energy, precision agriculture, and intelligent vehicle navigation and safety. In order to support these diverse needs, new national elevation data with higher resolution and accuracy are needed. The 3D Elevation Program (3DEP) initiative was developed to meet the majority of these needs and it is expected that 3DEP will result in new, unimagined information services that would result in job growth and the transformation of the geospatial community. Private-sector data collection companies are continuously evolving sensors and positioning technologies that are needed to collect improved elevation data. An initiative of this scope might also provide an opportunity for companies to improve their capabilities and produce even higher data quality and consistency at a pace that might not have otherwise occurred.

  12. Usefulness of ST elevation score by using vector-projected virtual 187-channel ECG for risk stratification in patients with Brugada-type ECG pattern

    Directory of Open Access Journals (Sweden)

    Shoko Ishikawa

    2012-08-01

    Conclusion: The ST elevation score in VP-ECG objectively documented the degree of ST elevation in surface ECG in Brugada-type ECG patterns. The ST-elevation score might be useful for risk stratification in patients with asymptomatic Brugada syndrome.

  13. Combination of hand mapping and automatic mapping to reveal the Miocene high elevation Pyrenean peneplain

    Science.gov (United States)

    Bosch, Gemma V.; Babault, Julien; Van Den Driessche, Jean

    2016-04-01

    A striking feature of the morphology of the Pyrenees is the occurrence of high-elevation, low-relief surfaces, which are interpreted as remnants of a single Miocene planation surface. Whether the original surface was uplifted or developed at high altitude is debated. This "Miocene Pyrenean peneplain" has been dissected by fluvial and glacial erosion during the Quaternary. Reworking by glacial erosion also provides new smooth surfaces such as glacial cirque floors that must not be confused with the remnants of the original planation surface. The later are convex-up landforms whereas glacial cirque floors are concave-up landforms. To reveal the Miocene high-elevation Pyrenean peneplain, we combined hand mapping and automatic mapping at the scale of the whole chain. From previous mapping in literature and from our own field work, we first perform a map of both the Miocene planation surface remnants and the Quaternary glacial cirque floors. Using Digital Elevation Models, numerical parameters were extracted from this map to characterize the two types of smooth surfaces. The slope is the parameter that helps to delimitate and differentiate the smooth surfaces from the rest of the Pyrenean topography. To distinguish between the two types of smooth surfaces we used the Topographic Index (TPI). This parameter is the difference between the elevation of a point and the mean elevation. Choosing the pertinent radius according to the scale of the landform to map, and the pertinent values interval, we can differentiate the planation surface (convex-up) from the glacial cirque floors (concave-up). A sensitivity test was performed to determine the best radius and the best interval for TPI and slope values to distinguish between the two types of smooth surfaces. Finally, we used a combination of slope values, TPI values and radius to determine automatically the high-elevation, low-relief surfaces in the entire Pyrenees. We verified in the field the presence of the newly mapped high-elevation

  14. Atmospheric deposition and watershed nitrogen export along an elevational gradient in the Catskill Mountains, New York

    Science.gov (United States)

    Lawrence, G.B.; Lovett, Gary M.; Baevsky, Y.H.

    2000-01-01

    Cumulative effects of atmospheric N deposition may increase N export from watersheds and contribute to the acidification of surface waters, but natural factors (such as forest productivity and soil drainage) that affect forest N cycling can also control watershed N export. To identify factors that are related to stream-water export of N, elevational gradients in atmospheric deposition and natural processes were evaluated in a steep, first-order watershed in the Catskill Mountains of New York, from 1991 to 1994. Atmospheric deposition of SO4/2-, and probably N, increased with increasing elevation within this watershed. Stream-water concentrations of SO4/2- increased with increasing elevation throughout the year, whereas stream-water concentrations of NO3/- decreased with increasing elevation during the winter and spring snowmelt period, and showed no relation with elevation during the growing season or the fall. Annual export of N in stream water for the overall watershed equaled 12% to 17% of the total atmospheric input on the basis of two methods of estimation. This percentage decreased with increasing elevation, from about 25% in the lowest subwatershed to 7% in the highest subwatershed; a probable result of an upslope increase in the thickness of the surface organic horizon, attributable to an elevational gradient in temperature that slows decomposition rates at upper elevations. Balsam fir stands, more prevalent at upper elevations than lower elevations, may also affect the gradient of subwatershed N export by altering nitrification rates in the soil. Variations in climate and vegetation must be considered to determine how future trends in atmospheric deposition will effect watershed export of nitrogen.

  15. Processes leading to increased soil organic carbon in a Mojave Desert ecosystem under elevated CO2

    Science.gov (United States)

    Koyama, A.; Evans, R. D.

    2011-12-01

    We observed increased soil organic carbon (SOC) following ten years of elevated atmospheric CO2 treatment at the Nevada Desert FACE Facility in the Mojave Desert. Physical and chemical fractions of surface soils collected under the dominant shrub, Larrea tridentata (Larrea), and plant interspace were analyzed for particle size, plant-derived n-alkanes, microbial phospholipid fatty acids (PLFA) and neutral lipid fatty acids (NLFA) to explore potential mechanisms causing the observed increase in SOC. SOC concentrations under Larrea in bulk soils, coarse particulate organic matter (POM), fine POM and mineral-bound soil organic matter (SOM) under elevated CO2 were greater than those under ambient CO2 by 34%, 45%, 26% and 20%, respectively. Under Larrea, n-alkane concentrations were 52% greater under elevated compared to ambient CO2. Such increases in coarse POM and n-alkane concentrations suggest litter input from Larrea was at least one source for increased SOC under elevated CO2. While there was no significant difference in PLFA abundance between the CO2 treatments, elevated CO2 significantly increased the fungi to bacterial PLFA ratio. In addition, fungal and bacterial NLFA and NLFA 16:1ω5, a biomarker of arbuscular mycorrhizal fungi, were significantly higher under elevated than ambient CO2. These observations plus others suggest that Larrea allocated more photosynthate belowground to increased root exudation rather than increased fine root growth under elevated CO2. Thus, increased root exudates and microbial residues as well as episodic increases in litter input from Larrea are mechanisms behind the increased SOC under elevated CO2. Elevated CO2 did not increase SOC in surface soils in plant interspace despite incorporation of CO2 labeled with 13C under elevated CO2.

  16. Elevated tumour marker: an indication for imaging?

    LENUS (Irish Health Repository)

    McMahon, Colm J

    2012-02-01

    INTRODUCTION: The purpose of this study was to evaluate the utility of imaging examinations in patients with elevated tumour markers when (a) the tumour marker is not validated for as a primary diagnostic test; (b) the patient had no personal history of cancer and (c) the patient had no other imaging indication. MATERIALS AND METHODS: Patients without known cancer who had abnormal carcinoembryonic antigen, CA19-9, CA125 and\\/or CA15-3 serology over a one-year period were included. A retrospective medical record review was performed to assess the number of these cases who underwent imaging because of \\'elevated tumour marker\\' in the absence of a clinical indication for imaging. The number and result of these imaging studies were evaluated. RESULTS: Eight hundred and nineteen patients were included. Of those, 25 patients (mean age: 67.8 [range 41-91] y), were imaged to evaluate: \\'elevated tumour marker\\'. They underwent 29 imaging studies (mean [+\\/-standard deviation (SD)] per patient = 1.2 [+\\/-0.4]), and had 42 elevated tumour marker serology tests (mean [+\\/-SD] per patient = 1.7 [+\\/-0.7]). Four patients had >1 imaging test. No patient had an imaging study which diagnosed a malignancy or explained the elevated tumour marker. CONCLUSION: The non-judicious use of tumour markers can prompt further unnecessary investigations including imaging. In this study, there was no positive diagnostic yield for imaging performed for investigation of \\'elevated tumour marker\\'. \\'Elevated tumour marker\\

  17. Analysis of heavy-rain-producing elevated thunderstorms in the MO-KS-OK region of the United States

    Science.gov (United States)

    McCoy, Laurel

    Most elevated thunderstorms in the United States occur in the Midwest, with a maximum in eastern Kansas (Colman 1990a). Elevated thunderstorms are defined as thunderstorms that occur over a very stable surface boundary layer (Colman 1990b). They may be better defined as convection occurring over a stable layer near the surface, essentially cut off from surface-based instability (Corfidi et al. 2006). Elevated mesoscale convective systems produce 30-70% of the total rainfall during the warm season over the Central Plains (Moore et al. 2003). 1.1 Purpose Elevated thunderstorms are still not very well understood. Elevated convection can take a variety of forms, and can be very similar to surface-based convection. Corfidi et al. (2006) describe the challenge of finding the originating layer of parcels making up a convective cloud. Surface-based convection often incorporates elevated parcels, and elevated convection can bring surface parcels into its updraft. The distinction between the two types of storms can be defined by where most of the parcels originate. This becomes especially hard to distinguish as convection transitions from surface-based to elevated and vice-versa (Corfidi et al. 2006). Colman (1990a), in his study, used three criteria to delineate elevated thunderstorm station reports from surface-based thunderstorm station reports: 1) The observation must lie on the cold side of an analyzed front that shows a clear contrast in temperature, dew-point temperature, and wind. 2) The station's wind, temperature, and dew-point temperature must be qualitatively similar to the immediately surrounding values. 3) The surface air on the warm side of the analyzed front must have a higher equivalent potential temperature (thetae) than the air on the cold side of the front (Colman 1990a). These three criteria have been incorporated into several studies since for the evaluation of elevated convection (e.g., Grant 1995; Rochette and Moore 1996; Moore et al. 1998; Moore et

  18. Validation of DEM Data Derived from World View 3 Stereo Imagery for Low Elevation Majuro Atoll, Marshall Islands

    Science.gov (United States)

    The availability of surface elevation data for the Marshall Islands has been identified as a “massive” data gap for conducting vulnerability assessments and the subsequent development of climate change adaption strategies. Specifically, digital elevation model (DEM) data are need...

  19. Void growth and coalescence in metals deformed at elevated temperature

    DEFF Research Database (Denmark)

    Klöcker, H.; Tvergaard, Viggo

    2000-01-01

    For metals deformed at elevated temperatures the growth of voids to coalescence is studied numerically. The voids are assumed to be present from the beginning of deformation, and the rate of deformation considered is so high that void growth is dominated by power law creep of the material, without...... any noticeable effect of surface diffusion. Axisymmetric unit cell model computations are used to study void growth in a material containing a periodic array of voids, and the onset of the coalescence process is defined as the stage where plastic flow localizes in the ligaments between neighbouring...

  20. The Tilt of the Elevator Shaft of Bunker Skutina

    Directory of Open Access Journals (Sweden)

    Pavel KALENDA

    2014-06-01

    Full Text Available The measurement of deformations of the elevator shaft in the Skutina fortress between the 2nd floor and the depth of 33 m below the surface took place in 2009. These measurements showed that, in addition to the tides, the diurnal thermoelastic wave deforms the body of the bunker, particularly in the NS direction. The amplitude of this deformation depends mainly on the cloudiness (opposite to the irradiance. Morning and evening deformation curves depend mainly on the time of sunrise and the geometry of the body of the bunker (irradiance of the bunker walls and less of the outside temperature.

  1. Adaptive patterns of movement during arm elevation test in patients with shoulder impingement syndrome.

    Science.gov (United States)

    Lin, Jiu-jenq; Hsieh, Shih-Chang; Cheng, Wei-Cheng; Chen, Wei Chun; Lai, Yuta

    2011-05-01

    The purpose of this study was to determine if a distinctive characteristic exists in the pattern of movement (scapular elevation and upward rotation to reduce impingement) and associated muscular activities during arm elevation in subjects with shoulder impingement (SI) that is associated with the severity of the disease. Fourteen subjects (7 amateur athletes and 7 student athletes) with SI and 7 controls performed arm elevation in the scapular plane. Scapular kinematics (upward rotation, elevation, tipping, and scapulohumeral rhythm) and muscular activity [upper trapezius (UT), lower trapezius (LT), serratus anterior (SA), and deltoid] were measured by an electromagnetic motion tracking system and surface electromyography, respectively. Subjects with SI had greater elevation of the scapula (11.9 mm, p impingement during arm elevation in subjects with SI. Assessing scapular elevation during arm elevation may be a useful functional marker for evaluating impingement status and associated muscle function. Additionally, SA and LT muscle strengthening may improve SI. Copyright © 2010 Orthopaedic Research Society.

  2. Hurricane Katrina sediment slowed elevation loss in subsiding brackish marshes of the Mississippi River delta

    Science.gov (United States)

    McKee, K.L.; Cherry, J.A.

    2009-01-01

    Although hurricanes can damage or destroy coastal wetlands, they may play a beneficial role in reinvigorating marshes by delivering sediments that raise soil elevations and stimulate organic matter production. Hurricane Katrina altered elevation dynamics of two subsiding brackish marshes in the Mississippi River deltaic plain by adding 3 to 8 cm of sediment to the soil surface in August 2005. Soil elevations at both sites subsequently declined due to continued subsidence, but net elevation gain was still positive at both Pearl River (+1.7 cm) and Big Branch (+0.7 cm) marshes two years after the hurricane. At Big Branch where storm sediments had higher organic matter and water contents, post-storm elevation loss was more rapid due to initial compaction of the storm layer in combination with root-zone collapse. In contrast, elevation loss was slower at Pearl River where the storm deposit (high sand content) did not compact and the root zone did not collapse. Vegetation at both sites fully recovered within one year, and accumulation of root matter at Big Branch increased 10-fold from 2005 to 2006, suggesting that the hurricane stimulated belowground productivity. Results of this study imply that hurricane sediment may benefit subsiding marshes by slowing elevation loss. However, long-term effects of hurricane sediment on elevation dynamics will depend not only on the amount of sediment deposited, but on sediment texture and resistance to compaction as well as on changes in organic matter accumulation in the years following the hurricane.

  3. King Cove, Alaska Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  4. Midway Atoll Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  5. Arecibo, Puerto Rico Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  6. Keauhou, Hawaii Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  7. Craig, Alaska Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  8. Shemya, Alaska Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  9. Daytona Beach, Florida Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  10. Kawaihae, Hawaii Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  11. Cordova, Alaska Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  12. Arena Cove, California Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  13. Sand Point, Alaska Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  14. Montauk, New York Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  15. Atka, Alaska Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  16. Monterey, California Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  17. Garibaldi, Oregon Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  18. Increasing heel skin perfusion by elevation.

    Science.gov (United States)

    Huber, Jacqueline; Reddy, Raj; Pitham, Tom; Huber, David

    2008-01-01

    To determine the efficacy of elevation in the primary prevention and treatment of pressure ulcers by studying the blood flow in tissue at risk of ulceration. A prospective study was used to compare different preventative devices with an elevating prosthesis. : Wollongong Hospital Wollongong, New South Wales, Australia. Normal subjects and subjects with vasculopathy were tested with their heel resting on a hospital bed, medical-grade lamb's wool, or a viscoelastic gel overlay, with or without the test prosthesis. Skin perfusion was measured throughout using a laser Doppler monitor. A device designed to elevate the heel off the bed and distribute the weight of the leg and foot on the calf. Heel capillary blood perfusion. Perfusion in the heel was significantly greater when elevated than when using the other devices tested. The differences in mean red blood cell flux were significant, with P pressure ulcer prevention and treatment and should be incorporated into health care practice.

  19. Juneau, Alaska Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) to support individual coastal States as part of the...

  20. Chenega, Alaska Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) to support individual coastal States as part of the...

  1. Mariana Trench Bathymetric Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) created a bathymetric digital elevation model (DEM) for the Mariana Trench and adjacent seafloor in the Western...

  2. Shaded Relief of Minnesota Elevation - Black & White

    Data.gov (United States)

    Minnesota Department of Natural Resources — This file is a product of a shaded relief process on the 30 meter resolution Digital Elevation Model data (dem30im3). This image was created using a custom AML...

  3. Nikolski, Alaska Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  4. ASTER Global Digital Elevation Model V002

    Data.gov (United States)

    National Aeronautics and Space Administration — The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Global Digital Elevation Model (GDEM) was developed jointly by the U.S. National...

  5. La Push, Washington Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  6. Nantucket, Massachusetts Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  7. Ocean City, Maryland Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  8. Hilo, Hawaii Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  9. Portland, Maine Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  10. Hanalei, Hawaii Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  11. Chignik, Alaska Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  12. Adak, Alaska Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  13. Puerto Rico Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  14. Kachemak Bay, Alaska Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  15. Lahaina, Hawaii Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  16. Oahu, Hawaii Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  17. Santa Barbara, California Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  18. Central Oregon Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  19. Virginia Beach, Virginia Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  20. Galveston, Texas Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  1. Biloxi, Mississippi Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  2. Ponce, Puerto Rico Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  3. Corpus Christi, Texas Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  4. ASTER Digital Elevation Model V003

    Data.gov (United States)

    National Aeronautics and Space Administration — The ASTER Digital Elevation Model (DEM) product is generated using bands 3N (nadir-viewing) and 3B (backward-viewing) of an ASTER Level-1A image acquired by the...

  5. Savannah, Georgia Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  6. Moral elevation reduces prejudice against gay men.

    Science.gov (United States)

    Lai, Calvin K; Haidt, Jonathan; Nosek, Brian A

    2014-01-01

    Disgust is linked to social evaluation. People with higher disgust sensitivity exhibit more sexual prejudice, and inducing disgust increases sexual prejudice. We tested whether inducing moral elevation, the theoretical opposite of disgust, would reduce sexual prejudice. In four studies (N = 3622), we induced elevation with inspiring videos and then measured sexual prejudice with implicit and explicit measures. Compared to control videos that elicited no particular affective state, we found that elevation reduced implicit and explicit sexual prejudice, albeit very slightly. No effect was observed when the target of social evaluation was changed to race (Black-White). Inducing amusement, another positive emotion, did not significantly affect sexual prejudice. We conclude that elevation weakly but reliably reduces prejudice towards gay men.

  7. Grain Elevators: New Source Performance Standards (NSPS)

    Science.gov (United States)

    The New Source Performance Standards (NSPS) for Grain Elevators aims to reduce particulate matter pollution. The new amendments seek to clarify definitions, and requirements, as well as propose new regulations on particulate matter emissions

  8. Elevator mechanism and method for scintillation detectors

    International Nuclear Information System (INIS)

    Frank, E.

    1975-01-01

    An elevator mechanism and method for raising and lowering radioactive samples through a shielded vertical counting chamber in a benchtop scintillation detector is described. The elevator mechanism adds little or nothing to the height of the detector by using an elongated flexible member such as a metal tape secured to the bottom of the elevator platform and extending downwardly through the counting chamber and its bottom shielding, where the tape is bent laterally for connection to a drive means. In the particular embodiment illustrated, the tape is bent laterally below the bottom shielding for the counting chamber, and then upwardly along or through one side of the shielding to a reel at the top of the shielding. The tape is wound onto the reel, and the reel is driven by a reversible motor which winds and unwinds the tape on the reel to raise and lower the elevator platform

  9. Southeast Alaska Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) to support individual coastal States as part of the...

  10. Taholah, Washington Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  11. Whittier, Alaska Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) to support individual coastal States as part of the...

  12. Gustavus, Alaska Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) to support individual coastal States as part of the...

  13. Fajardo, Puerto Rico Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  14. Port Alexander Alaska Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) to support individual coastal States as part of the...

  15. Dutch Harbor, Alaska Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  16. Port Orford, Oregon Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  17. Panama City, Florida Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  18. Guayama, Puerto Rico Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  19. Shaded Relief of Minnesota Elevation - Color

    Data.gov (United States)

    Minnesota Department of Natural Resources — This file is a product of a shaded relief process on the 30 meter resolution Digital Elevation Model data (dem30im3). This image was created using a custom AML...

  20. New Orleans, Louisiana Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions in the Gulf of Mexico....

  1. Elevated temperature erosive wear of metallic materials

    International Nuclear Information System (INIS)

    Roy, Manish

    2006-01-01

    Solid particle erosion of metals and alloys at elevated temperature is governed by the nature of the interaction between erosion and oxidation, which, in turn, is determined by the thickness, pliability, morphology, adhesion characteristics and toughness of the oxide scale. The main objective of this paper is to critically review the present state of understanding of the elevated temperature erosion behaviour of metals and alloys. First of all, the erosion testing at elevated temperature is reviewed. This is followed by discussion of the essential features of elevated temperature erosion with special emphasis on microscopic observation, giving details of the erosion-oxidation (E-O) interaction mechanisms. The E-O interaction has been elaborated in the subsequent section. The E-O interaction includes E-O maps, analysis of transition criteria from one erosion mechanism to another mechanism and quantification of enhanced oxidation kinetics during erosion. Finally, the relevant areas for future studies are indicated. (topical review)

  2. Electrostatic Climber for Space Elevator and Launcher

    OpenAIRE

    Bolonkin, A.

    2007-01-01

    Author details research on the new, very prospective, electrostatic Space Elevator climber based on a new electrostatic linear engine previously offered at the 42nd Joint Propulsion Conference (AIAA-2006-5229) and published in AEAT, Vol.78, No.6, 2006, pp. 502-508. The electrostatic climber discussed can have any speed (and braking), the energy for climber movement is delivered by a lightweight high-voltage line into a Space Elevator-holding cable from Earth electric generator. This electric ...

  3. Elevator Illusion and Gaze Direction in Hypergravity

    Science.gov (United States)

    Cohen, Malcolm M.; Hargens, Alan (Technical Monitor)

    1995-01-01

    A luminous visual target in a dark hypergravity (Gz greater than 1) environment appears to be elevated above its true physical position. This "elevator illusion" has been attributed to changes in oculomotor control caused by increased stimulation of the otolith organs. Data relating the magnitude of the illusion to the magnitude of the changes in oculomotor control have been lacking. The present study provides such data.

  4. Airborne Surface Profiling of Alaskan Glaciers

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set consists of glacier outline, laser altimetry profile, and surface elevation change data for 46 glaciers in Alaska and British Columbia, Canada,...

  5. Global elevational diversity and diversification of birds.

    Science.gov (United States)

    Quintero, Ignacio; Jetz, Walter

    2018-03-08

    Mountain ranges harbour exceptionally high biodiversity, which is now under threat from rapid environmental change. However, despite decades of effort, the limited availability of data and analytical tools has prevented a robust and truly global characterization of elevational biodiversity gradients and their evolutionary origins. This has hampered a general understanding of the processes involved in the assembly and maintenance of montane communities. Here we show that a worldwide mid-elevation peak in bird richness is driven by wide-ranging species and disappears when we use a subsampling procedure that ensures even species representation in space and facilitates evolutionary interpretation. Instead, richness corrected for range size declines linearly with increasing elevation. We find that the more depauperate assemblages at higher elevations are characterized by higher rates of diversification across all mountain regions, rejecting the idea that lower recent diversification rates are the general cause of less diverse biota. Across all elevations, assemblages on mountains with high rates of past temperature change exhibit more rapid diversification, highlighting the importance of climatic fluctuations in driving the evolutionary dynamics of mountain biodiversity. While different geomorphological and climatic attributes of mountain regions have been pivotal in determining the remarkable richness gradients observed today, our results underscore the role of ongoing and often very recent diversification processes in maintaining the unique and highly adapted biodiversity of higher elevations.

  6. Energy considerations in the partial space elevator

    Science.gov (United States)

    Woo, Pamela; Misra, Arun K.

    2014-06-01

    The space elevator has been proposed as an alternate method for space transportation. A partial elevator is composed of a tether of several hundreds of kilometres, held vertically in tension between two end masses, with its centre of orbit placed at the geosynchronous orbit. A spacecraft can dock at the lower end, and then use the climber on the elevator to ascend to higher altitudes. In this paper, energy calculations are performed, to determine whether a partial elevator can provide sufficient savings in operational costs, compared to the traditional rocket-powered launch. The energy required to launch a spacecraft from a Low Earth Orbit (LEO) to the geostationary orbit (GEO) is calculated for two trajectories. In the first trajectory, the spacecraft travels from LEO to GEO via a Hohmann transfer. In the second trajectory, the spacecraft travels from LEO to the lower end of the partial space elevator with a Hohmann transfer, and then uses the elevator to climb to GEO. The total energy required is compared between the two trajectories. The effects of tether length, spacecraft-to-climber mass ratio, altitude of LEO, and tether material are investigated.

  7. P Elevator: An Innovatively Designed Elevator for Extraction of Third Molars.

    Science.gov (United States)

    Singh, Pradeep; Xiao, Shui Sheng; Ajmera, Deepal Haresh

    2015-01-01

    To modify the conventional straight elevator with a unique and innovative design in respect to approach and accessibility during extraction for patients with abrasions around corners of the mouth and with thick buccal mucosa, without causing overstretching of angles of the mouth. The shank of the straight elevator in the shape of a 'U' was modified, giving it a shape similar to 'P' in the English alphabet hence it is named the P Elevator. The P elevator utilises a 'U' shaped bend in the shank of the conventional straight elevator making space for the buccal soft tissues and the angle of the mouth, to accommodate properly in the 'U' shank. The application of this elevator in the successful removal of third molars is described. Two hundred patients underwent extraction of third molars with the P elevator including 166 patients with disimpaction of all third molars, 23 patients with abrasion around the angle of the mouth, and 11 patients with thick buccal mucosa. Satisfactory results were obtained in all the cases with no postoperative complications. The P elevator permits prudent, meticulous, innovative and proficient extraction of third molars in patients with thick buccal mucosa and abrasions around the angle of the mouth, without overstretching the corners of the mouth. We introduce novel applications of the P elevator in third molar extraction that provide substantial advantages over a conventional straight elevator.

  8. Lunar transportation scenarios utilising the Space Elevator

    Science.gov (United States)

    Engel, Kilian A.

    2005-07-01

    The Space Elevator (SE) concept has begun to receive an increasing amount of attention within the space community over the past couple of years and is no longer widely dismissed as pure science fiction. In light of the renewed interest in a, possibly sustained, human presence on the Moon and the fact that transportation and logistics form the bottleneck of many conceivable lunar missions, it is interesting to investigate what role the SE could eventually play in implementing an efficient Earth to Moon transportation system. The elevator allows vehicles to ascend from Earth and be injected into a trans-lunar trajectory without the use of chemical thrusters, thus eliminating gravity loss, aerodynamic loss and the need of high thrust multistage launch systems. Such a system therefore promises substantial savings of propellant and structural mass and could greatly increase the efficiency of Earth to Moon transportation. This paper analyzes different elevator-based trans-lunar transportation scenarios and characterizes them in terms of a number of benchmark figures. The transportation scenarios include direct elevator-launched trans-lunar trajectories, elevator-launched trajectories via L1 and L2, as well as launch from an Earth-based elevator and subsequent rendezvous with lunar elevators placed either on the near or on the far side of the Moon. The benchmark figures by which the different transfer options are characterized and evaluated include release radius (RR), required Δv, transfer times as well as other factors such as accessibility of different lunar latitudes, frequency of launch opportunities and mission complexity. The performances of the different lunar transfer options are compared with each other as well as with the performance of conventional mission concepts, represented by Apollo.

  9. Lunar transportation scenarios utilising the Space Elevator.

    Science.gov (United States)

    Engel, Kilian A

    2005-01-01

    The Space Elevator (SE) concept has begun to receive an increasing amount of attention within the space community over the past couple of years and is no longer widely dismissed as pure science fiction. In light of the renewed interest in a, possibly sustained, human presence on the Moon and the fact that transportation and logistics form the bottleneck of many conceivable lunar missions, it is interesting to investigate what role the SE could eventually play in implementing an efficient Earth to Moon transportation system. The elevator allows vehicles to ascend from Earth and be injected into a trans-lunar trajectory without the use of chemical thrusters, thus eliminating gravity loss, aerodynamic loss and the need of high thrust multistage launch systems. Such a system therefore promises substantial savings of propellant and structural mass and could greatly increase the efficiency of Earth to Moon transportation. This paper analyzes different elevator-based trans-lunar transportation scenarios and characterizes them in terms of a number of benchmark figures. The transportation scenarios include direct elevator-launched trans-lunar trajectories, elevator launched trajectories via L1 and L2, as well as launch from an Earth-based elevator and subsequent rendezvous with lunar elevators placed either on the near or on the far side of the Moon. The benchmark figures by which the different transfer options are characterized and evaluated include release radius (RR), required delta v, transfer times as well as other factors such as accessibility of different lunar latitudes, frequency of launch opportunities and mission complexity. The performances of the different lunar transfer options are compared with each other as well as with the performance of conventional mission concepts, represented by Apollo. c2005 Elsevier Ltd. All rights reserved.

  10. Scales of snow depth variability in high elevation rangeland sagebrush

    Science.gov (United States)

    Tedesche, Molly E.; Fassnacht, Steven R.; Meiman, Paul J.

    2017-09-01

    In high elevation semi-arid rangelands, sagebrush and other shrubs can affect transport and deposition of wind-blown snow, enabling the formation of snowdrifts. Datasets from three field experiments were used to investigate the scales of spatial variability of snow depth around big mountain sagebrush ( Artemisia tridentata Nutt.) at a high elevation plateau rangeland in North Park, Colorado, during the winters of 2002, 2003, and 2008. Data were collected at multiple resolutions (0.05 to 25 m) and extents (2 to 1000 m). Finer scale data were collected specifically for this study to examine the correlation between snow depth, sagebrush microtopography, the ground surface, and the snow surface, as well as the temporal consistency of snow depth patterns. Variograms were used to identify the spatial structure and the Moran's I statistic was used to determine the spatial correlation. Results show some temporal consistency in snow depth at several scales. Plot scale snow depth variability is partly a function of the nature of individual shrubs, as there is some correlation between the spatial structure of snow depth and sagebrush, as well as between the ground and snow depth. The optimal sampling resolution appears to be 25-cm, but over a large area, this would require a multitude of samples, and thus a random stratified approach is recommended with a fine measurement resolution of 5-cm.

  11. Scientific return of a lunar elevator

    Science.gov (United States)

    Eubanks, T. M.; Radley, C. F.

    2016-11-01

    The concept of a space elevator dates back to Tsilokovsky, but they are not commonly considered in near-term plans for space exploration, perhaps because a terrestrial elevator would not be possible without considerable improvements in tether material. A Lunar Space Elevator (LSE), however, can be built with current technology using commercially available tether polymers. This paper considers missions leading to infrastructure capable of shortening the time, lowering the cost and enhancing the capabilities of robotic and human explorers. These missions use planetary scale tethers, strings many thousands of kilometers long stabilized either by rotation or by gravitational gradients. These systems promise major reduction in transport costs versus chemical rockets, in a rapid timeframe, for a modest investment. Science will thus benefit as well as commercial activities.

  12. Advanced composite elevator for Boeing 727 aircraft

    Science.gov (United States)

    1979-01-01

    Detail design activities are reported for a program to develop an advanced composites elevator for the Boeing 727 commercial transport. Design activities include discussion of the full scale ground test and flight test activities, the ancillary test programs, sustaining efforts, weight status, and the production status. Prior to flight testing of the advanced composites elevator, ground, flight flutter, and stability and control test plans were reviewed and approved by the FAA. Both the ground test and the flight test were conducted according to the approved plan, and were witnessed by the FAA. Three and one half shipsets have now been fabricated without any significant difficulty being encountered. Two elevator system shipsets were weighed, and results validated the 26% predicted weight reduction. The program is on schedule.

  13. Vertical vibration analysis for elevator compensating sheave

    International Nuclear Information System (INIS)

    Watanabe, Seiji; Nakazawa, Daisuke; Fukui, Daiki; Okawa, Takeya

    2013-01-01

    Most elevators applied to tall buildings include compensating ropes to satisfy the balanced rope tension between the car and the counter weight. The compensating ropes receive tension by the compensating sheave, which is installed at the bottom space of the elevator shaft. The compensating sheave is only suspended by the compensating ropes, therefore, the sheave can move vertically while the car is traveling. This paper shows the elevator dynamic model to evaluate the vertical motion of the compensating sheave. Especially, behavior in emergency cases, such as brake activation and buffer strike, was investigated to evaluate the maximum upward motion of the sheave. The simulation results were validated by experiments and the most influenced factor for the sheave vertical motion was clarified

  14. Vertical vibration analysis for elevator compensating sheave

    Science.gov (United States)

    Watanabe, Seiji; Okawa, Takeya; Nakazawa, Daisuke; Fukui, Daiki

    2013-07-01

    Most elevators applied to tall buildings include compensating ropes to satisfy the balanced rope tension between the car and the counter weight. The compensating ropes receive tension by the compensating sheave, which is installed at the bottom space of the elevator shaft. The compensating sheave is only suspended by the compensating ropes, therefore, the sheave can move vertically while the car is traveling. This paper shows the elevator dynamic model to evaluate the vertical motion of the compensating sheave. Especially, behavior in emergency cases, such as brake activation and buffer strike, was investigated to evaluate the maximum upward motion of the sheave. The simulation results were validated by experiments and the most influenced factor for the sheave vertical motion was clarified.

  15. Calculation and Error Analysis of a Digital Elevation Model of Hofsjokull, Iceland from SAR Interferometry

    Science.gov (United States)

    Barton, Jonathan S.; Hall, Dorothy K.; Sigurosson, Oddur; Williams, Richard S., Jr.; Smith, Laurence C.; Garvin, James B.

    1999-01-01

    Two ascending European Space Agency (ESA) Earth Resources Satellites (ERS)-1/-2 tandem-mode, synthetic aperture radar (SAR) pairs are used to calculate the surface elevation of Hofsjokull, an ice cap in central Iceland. The motion component of the interferometric phase is calculated using the 30 arc-second resolution USGS GTOPO30 global digital elevation product and one of the ERS tandem pairs. The topography is then derived by subtracting the motion component from the other tandem pair. In order to assess the accuracy of the resultant digital elevation model (DEM), a geodetic airborne laser-altimetry swath is compared with the elevations derived from the interferometry. The DEM is also compared with elevations derived from a digitized topographic map of the ice cap from the University of Iceland Science Institute. Results show that low temporal correlation is a significant problem for the application of interferometry to small, low-elevation ice caps, even over a one-day repeat interval, and especially at the higher elevations. Results also show that an uncompensated error in the phase, ramping from northwest to southeast, present after tying the DEM to ground-control points, has resulted in a systematic error across the DEM.

  16. Remote sensing and photogrammetric studies: Part D: repeatability of elevation measurements--Apollo photography

    Science.gov (United States)

    Wu, Sherman S.C.; Schafer, Francis J.; Nakata, Gary M.; Jordan, Raymond

    1973-01-01

    Stereoscopic photographs of the Moon taken by the metric and panoramic cameras on board the service module of Apollo spacecraft provide a source for quantitative data on lunar topography. The accuracy of the topographic data depends, in part, on the repeatability of elevation measurements. The repeatability depends on contrast in the stereoscopic image and is affected by many factors, such as photographic quality, the photogrammetric instrument used, and illumination conditions. For the Moon, illumination conditions are important so that repeatability of elevation measurements may be statistically related to Sun elevation angles, local slopes, and albedos of surfaces. We have examined the effect of Sun elevation angle on repeatability, using Apollo 15 photographs (Wu, unpublished data), and extended the results to slope-related effects.

  17. Strength properties of concrete at elevated temperatures

    International Nuclear Information System (INIS)

    Freskakis, G.N.; Burrow, R.C.; Debbas, E.B.

    1979-01-01

    A study is presented concerning the compressive strength, modulus of elasticity, and stress-strain relationships of concrete at elevated temperatures. A review of published results provides information for the development of upper and lower bound relationships for compressive strength and the modulus of elasticity and establishes exposure conditions for a lower bound thermal response. The relationships developed from the literature review are confirmed by the results of a verification test program. The strength and elasticity relationships provide a basis for the development of design stress-strain curves for concrete exposed to elevated temperatures

  18. Forest succession at elevated CO2

    Energy Technology Data Exchange (ETDEWEB)

    Clark, James S.; Schlesinger, William H.

    2002-02-01

    We tested hypotheses concerning the response of forest succession to elevated CO2 in the FACTS-1 site at the Duke Forest. We quantified growth and survival of naturally recruited seedlings, tree saplings, vines, and shrubs under ambient and elevated CO2. We planted seeds and seedlings to augment sample sites. We augmented CO2 treatments with estimates of shade tolerance and nutrient limitation while controlling for soil and light effects to place CO2 treatments within the context of natural variability at the site. Results are now being analyzed and used to parameterize forest models of CO2 response.

  19. Digital elevation modeling via curvature interpolation for LiDAR data

    Directory of Open Access Journals (Sweden)

    Hwamog Kim

    2016-03-01

    Full Text Available Digital elevation model (DEM is a three-dimensional (3D representation of a terrain's surface - for a planet (including Earth, moon, or asteroid - created from point cloud data which measure terrain elevation. Its modeling requires surface reconstruction for the scattered data, which is an ill-posed problem and most computational algorithms become overly expensive as the number of sample points increases. This article studies an effective partial differential equation (PDE-based algorithm, called the curvature interpolation method (CIM. The new method iteratively utilizes curvature information, estimated from an intermediate surface, to construct a reliable image surface that contains all of the data points. The CIM is applied for DEM for point cloud data acquired by light detection and ranging (LiDAR technology. It converges to a piecewise smooth image, requiring O(N operations independently of the number of sample points, where $N$ is the number of grid points.

  20. Within-footprint roughness measurements using ICESat/GLAS waveform and LVIS elevation

    International Nuclear Information System (INIS)

    Li, Xiaolu; Xu, Kai; Xu, Lijun

    2016-01-01

    The surface roughness is an important characteristic over an ice sheet or glacier, since it is an identification of boundary-layer meteorology and is an important limiter on the accuracy of surface-height measurements. In this paper, we propose a simulation method to derive the within-footprint roughness (called simulation-derived roughness) using ICESat/GLAS echo waveform, laser vegetation imaging sensor (LVIS) elevations, and laser profile array (LPA) images of ICESat/GLAS. By dividing the within-footprint surface into several elements, a simulation echo waveform can be obtained as the sum of the elementary pulses reflected from each surface element. The elevation of the surface elements, which is utilized to get the return time of the elementary pulses, is implemented based on an LVIS interpolated elevation using a radial basis function (RBF) neural network. The intensity of the elementary pulses can be obtained from the thresholded LPA images. Based on the return time and the intensity of the elementary pulses, we used the particle swarm optimization (PSO) method to approximate the simulation waveform to the ICESat/GLAS echo waveform. The full width at half maximum) (FWHM) of the elementary pulse was extracted from the simulation waveform for estimating the simulation-derived roughness. By comparing with the elevation-derived roughness (derived from the elevation) and the waveform-derived roughness (derived from the ICESat/GLAS waveform), the proposed algorithm can exclude the slope effect from waveform width broadening for describing the roughness of the surface elements. (paper)

  1. Nurses' accuracy in estimating backrest elevation

    African Journals Online (AJOL)

    2007-02-08

    Feb 8, 2007 ... associated pneumonia (VAP).1 Backrest elevation is defined as the angle of the backrest ... Aspiration of gastric contents is thought to be a major mechanism in the ... associated pneumonia (VAP) Compliance with this recommendation may be affected by nurses' knowledge of the recommendation and their ...

  2. Complement elevation in spinal cord injury.

    Science.gov (United States)

    Rebhun, J; Botvin, J

    1980-05-01

    Laboratory studies revealed an elevated complement in 66% of patients with spinal cord injury. It is postulated that the activated complement may be a component of self-feeding immunological mechanism responsible for the failure of regeneration of a mature mammalian spinal cord. There was no evidence that such an injury had any effect on pre-existing atopy.

  3. Elevated transferrin saturation and risk of diabetes

    DEFF Research Database (Denmark)

    Ellervik, Christina; Mandrup-Poulsen, Thomas; Andersen, Henrik Ullits

    2011-01-01

    OBJECTIVE We tested the hypothesis that elevated transferrin saturation is associated with an increased risk of any form of diabetes, as well as type 1 or type 2 diabetes separately. RESEARCH DESIGN AND METHODS We used two general population studies, The Copenhagen City Heart Study (CCHS, N = 9...

  4. Elevated fetal steroidogenic activity in autism

    Science.gov (United States)

    Baron-Cohen, S; Auyeung, B; Nørgaard-Pedersen, B; Hougaard, D M; Abdallah, M W; Melgaard, L; Cohen, A S; Chakrabarti, B; Ruta, L; Lombardo, M V

    2015-01-01

    Autism affects males more than females, giving rise to the idea that the influence of steroid hormones on early fetal brain development may be one important early biological risk factor. Utilizing the Danish Historic Birth Cohort and Danish Psychiatric Central Register, we identified all amniotic fluid samples of males born between 1993 and 1999 who later received ICD-10 (International Classification of Diseases, 10th Revision) diagnoses of autism, Asperger syndrome or PDD-NOS (pervasive developmental disorder not otherwise specified) (n=128) compared with matched typically developing controls. Concentration levels of Δ4 sex steroids (progesterone, 17α-hydroxy-progesterone, androstenedione and testosterone) and cortisol were measured with liquid chromatography tandem mass spectrometry. All hormones were positively associated with each other and principal component analysis confirmed that one generalized latent steroidogenic factor was driving much of the variation in the data. The autism group showed elevations across all hormones on this latent generalized steroidogenic factor (Cohen's d=0.37, P=0.0009) and this elevation was uniform across ICD-10 diagnostic label. These results provide the first direct evidence of elevated fetal steroidogenic activity in autism. Such elevations may be important as epigenetic fetal programming mechanisms and may interact with other important pathophysiological factors in autism. PMID:24888361

  5. Elevated extracellular potassium ion concentrations suppress ...

    African Journals Online (AJOL)

    To address this question, we examined how elevations of [K+]o affect hippocampal oscillations in Scn1a mutant mouse, a mouse model of Dravet syndrome, a devastating genetic-epilepsy associated with gliosis, a major cause of dysregulated K+ homeostasis in epileptic brain. Methods: To this end, performing local field ...

  6. 75 FR 59181 - Proposed Flood Elevation Determinations

    Science.gov (United States)

    2010-09-27

    ...) Depth in feet above State City/town/county Source of flooding Location ** ground [caret] Elevation in... of Southeast. the Town of Southeast. Muscoot River At the county boundary. +512 +509 Town of Carmel.... At the county boundary. +391 +393 Stephens Brook Approximately 250 feet +432 +433 Town of Patterson...

  7. 78 FR 5738 - Final Flood Elevation Determinations

    Science.gov (United States)

    2013-01-28

    ... in feet (NGVD) + Elevation in feet (NAVD) Depth in feet State City/town/county Source of flooding... of Winooski River. Barre, City of Montpelier, Town of Berlin. At county boundary +740 (approximately.... Approximately 60 feet +728 upstream of Water Street. Winooski River At Chittenden County +342 Town of Middlesex...

  8. 76 FR 72661 - Proposed Flood Elevation Determinations

    Science.gov (United States)

    2011-11-25

    ...) Depth in feet above State City/town/county Source of flooding Location ** ground [caret] Elevation in meters (MSL) Existing Modified Town of Richland, New York New York Town of Richland........ Lake Ontario Entire shoreline within Selkirk Shores State Park boundary None +249 New York Town of Richland...

  9. 75 FR 62751 - Proposed Flood Elevation Determinations

    Science.gov (United States)

    2010-10-13

    .../town/county Source of flooding Location ** ground [caret] Elevation in meters (MSL) Existing Modified Unincorporated Areas of Claiborne County, Tennessee Tennessee Unincorporated Areas of Clinch River Approximately 2.3 miles downstream of Big Barren Creek.... +1055 +1032 Claiborne County. [[Page 62752...

  10. 76 FR 40670 - Proposed Flood Elevation Determinations

    Science.gov (United States)

    2011-07-11

    ...) Depth in feet above State City/town/county Source of flooding Location ** ground [caret] Elevation in... Contentnea Creek +76 +77 Town of Black Creek, confluence. Unincorporated Areas of Wilson County... +63 Town of Stantonsburg, confluence. Unincorporated Areas of Wilson County. Approximately 0.8 mile...

  11. 75 FR 3171 - Final Flood Elevation Determinations

    Science.gov (United States)

    2010-01-20

    ... City/town/county Source of flooding Location Depth in feet above ground [caret]Elevation in meters (MSL... Approximately 990 feet +388 Unincorporated Areas of upstream of the Lauderdale County, Town confluence of... Unincorporated Areas of Lee County, Town of Shannon. Approximately 6,220 feet +252 upstream of State Highway 145...

  12. 76 FR 50960 - Proposed Flood Elevation Determinations

    Science.gov (United States)

    2011-08-17

    ...) Depth in feet above State City/town/county Source of flooding Location ** ground [caret] Elevation in..., Town downstream of the of Snow Hill, Wheat Swamp confluence. Unincorporated Areas of Greene County... Contentnea Creek +47 +41 Town of Snow Hill, confluence. Unincorporated Areas of Greene County. [[Page 50964...

  13. 76 FR 66887 - Proposed Flood Elevation Determinations

    Science.gov (United States)

    2011-10-28

    ...) Depth in feet above State City/town/county Source of flooding Location** ground [caret] Elevation in meters (MSL) Existing Modified Town of Richmond, Vermont Vermont Town of Richmond........ Winooski River... Incorporated Areas Little Thompson River At the downstream side None +4935 Town of Berthoud, of Weld County...

  14. 75 FR 67317 - Proposed Flood Elevation Determinations

    Science.gov (United States)

    2010-11-02

    ... above State City/town/county Source of flooding Location ** ground [caret] Elevation in meters (MSL) Existing Modified Unincorporated Areas of Butte-Silver Bow County, Montana Montana Unincorporated Areas of Basin Creek Approximately 1,000 feet upstream of I-90 +5468 +5469 Butte-Silver Bow County. Approximately...

  15. 76 FR 69665 - Final Flood Elevation Determinations

    Science.gov (United States)

    2011-11-09

    ... in feet (NGVD) + Elevation in feet (NAVD) State City/town/county Source of flooding Location Depth in...) Modified Summit County, Colorado, and Incorporated Areas Docket No.: FEMA-B-1049 Willow Creek At the confluence with + 8682 Town of Silverthorne, the Blue River. Unincorporated Areas of Summit County...

  16. 76 FR 68107 - Final Flood Elevation Determinations

    Science.gov (United States)

    2011-11-03

    ... in feet (NGVD) + Elevation in feet (NAVD) Depth in feet State City/town/county Source of flooding... Lee County. Approximately 796 feet +601 upstream of Thach Avenue. Town Creek Tributary 1 At the confluence with +460 City of Auburn, Town Creek. Unincorporated Areas of Lee County. Approximately 602 feet...

  17. 76 FR 59361 - Proposed Flood Elevation Determinations

    Science.gov (United States)

    2011-09-26

    ...) Depth in feet above State City/town/county Source of flooding Location ** ground [caret] Elevation in... County. At the Wash 10 East None +1455 divergence. Wash 11 East Approximately 600 feet None +1348 Town of... Town of Surprise, confluence. Unincorporated Areas of Maricopa County. At the Wash 12 East None +1514...

  18. 76 FR 8978 - Proposed Flood Elevation Determinations

    Science.gov (United States)

    2011-02-16

    .../town/county Source of flooding Location ** ground [caret] Elevation in meters (MSL) Existing Modified Unincorporated Areas of Yolo County, California California Unincorporated Areas of Cache Creek Settling Basin At........ Entire None +901 Town of shoreline Wolcottvill e, Unincorpora ted Areas of LaGrange County. * National...

  19. 76 FR 36482 - Proposed Flood Elevation Determinations

    Science.gov (United States)

    2011-06-22

    .../town/county Source of flooding Location ** ground [caret] Elevation in meters (MSL) Existing Modified City of Colonial Heights, Virginia Virginia City of Colonial Heights Old Town Creek Approximately 0.63... for inspection at 202 James Avenue, Colonial Heights, VA 23834. Unincorporated Areas of Halifax County...

  20. 76 FR 35119 - Final Flood Elevation Determinations

    Science.gov (United States)

    2011-06-16

    ... in feet (NGVD) + Elevation in feet (NAVD) Depth in feet State City/town/county Source of flooding... Town of Marana, the vicinity of Central Unincorporated Areas Arizona Project Canal of Pima County.... Messalonskee Stream At the County Road Bridge.... +105 Town of Oakland. At the City of Waterville/ +105...

  1. 77 FR 3625 - Final Flood Elevation Determinations

    Science.gov (United States)

    2012-01-25

    ... in feet (NGVD) + Elevation in feet (NAVD) State City/town/county Source of flooding Location Depth in... Sierra County, California, and Incorporated Areas Docket No.: FEMA-B-1128 Downie River Approximately 0.76 mile +2897 Unincorporated Areas of downstream of Jersey Sierra County. Flat Bridge. Approximately 167...

  2. 76 FR 3524 - Final Flood Elevation Determinations

    Science.gov (United States)

    2011-01-20

    ... effects from Kentucky River). the Kentucky River to Garrard County. approximately 932 feet upstream of Old..., City of The Colony, Town of Hebron, Unincorporated Areas of Denton County. Approximately 2,940 feet... Communities affected [caret] Elevation in meters (MSL) Modified Ashley County, Arkansas, and Incorporated...

  3. 77 FR 66788 - Proposed Flood Elevation Determinations

    Science.gov (United States)

    2012-11-07

    ... Town of Clarkstown. Old Mill Road. Approximately 600 feet +150 +151 downstream of Rockland Lake. Golf..., Orangetown/Town of Town of Orangetown. Clarkstown corporate limit. At the downstream side +67 +66 of Old Mill... and modified elevations, and communities affected for Rockland County, New York (All Jurisdictions...

  4. 76 FR 35111 - Final Flood Elevation Determinations

    Science.gov (United States)

    2011-06-16

    .... Conway County. Approximately 2.0 miles +301 upstream of Old Cherokee Road. * National Geodetic Vertical... inspection at the Town Hall, 34 West Main Street, Westborough, MA 01581. Marshall County, Mississippi, and... Communities affected [caret] Elevation in meters (MSL) Modified Conway County, Arkansas, and Incorporated...

  5. Kas Euroopale oma "Elevant"? / Tiina Lokk

    Index Scriptorium Estoniae

    Lokk, Tiina, 1955-

    2007-01-01

    Ilmar Raagi mängufilm "Klass" võitis 42. Karlovy Vary rahvusvahelise filmifestivalil kaks auhinda - ametliku kõrvalvõistlusprogrammi "East of the West" eripreemia "Special mention" ja Euroopa väärtfilmikinode keti Europa Cinemas preemia. Ka teistest võistlusprogrammi filmidest ja "Klassi" võrdlus Gus Van Santi filmiga "Elevant"

  6. Der er nye elever i klassen

    DEFF Research Database (Denmark)

    Weirsøe, Mathilde

    2010-01-01

    Etniske minoritetsbørn bliver udsat for 'naturlig' forskelsbehandling i de danske skoler, hvor der stadig undervises, som om alle elever hedder Jensen og Petersen. Det er på tide, at pædagogikken anerkender den etniske kompleksitet i vores samfund og indretter undervisningen derefter....

  7. Measuring elevated intracranial pressure through noninvasive methods

    DEFF Research Database (Denmark)

    Kristiansson, Helena; Nissborg, Emelie; Bartek, Jiri

    2013-01-01

    Elevated intracranial pressure (ICP) is an important cause of secondary brain injury, and a measurement of ICP is often of crucial value in neurosurgical and neurological patients. The gold standard for ICP monitoring is through an intraventricular catheter, but this invasive technique...

  8. ELEVATED TEMPERATURE EFFECTS ON THE ELECTRICAL ...

    African Journals Online (AJOL)

    The effects of elevated temperatures on the electrical properties of Bi metal probe to Si thin films had been investigated for electric field values 10-100V/m. Measurements of current (I) – voltage (V) characteristics were obtained at temperatures 300,320,340,360,380 and 400K respectively. The results indicated linear I–V ...

  9. Elevated Bladder Cancer Risk in New England

    Science.gov (United States)

    A new study has found that drinking water from private wells, particularly dug wells established during the first half of the 20th century, may have contributed to the elevated risk of bladder cancer that has been observed in Maine, New Hampshire, and Vermont for over 50 years.

  10. Troponin elevation after black widow spider envenomation.

    Science.gov (United States)

    Bush, Sean P; Davy, J Veeran

    2015-09-01

    Black widow spider envenomation generally results in self-limiting pain that can be treated in the emergency department (ED) with analgesics and benzodiazepines, usually with no further intervention. Occasionally, a patient has to be admitted or treated with antivenom for refractory pain or a venom-induced complication. We present the case of an 84-year-old man who presented to our ED with chest pain and dyspnea after being bitten on the foot by a western black widow spider (Lactrodectus hesperus). His initial cardiac troponin I (cTnI) was elevated at 0.07 ng/ml and continued to rise to a peak of 0.17 ng/ml. He also had rhabdomyolysis, another uncommon complication of black widow envenomation. An elevated cTnI generally signifies myocardial injury and is rarely seen after black widow envenomation. We discuss the possible etiologies for an elevated cardiac biomarker, in this context, and review potentially serious complications of widow spider envenomation presenting with chest symptoms and an elevated cardiac biomarker.

  11. 76 FR 72627 - Final Flood Elevation Determinations

    Science.gov (United States)

    2011-11-25

    ... Areas Docket Nos.: FEMA-B-1022 and FEMA-B-1117 Agua Fria Canyon Approximately 340 feet +3384... Unincorporated Areas of Doyle Drive. Iberia Parish. At the intersection with +16 Adrian Street. Gulf of Mexico... AE zones have been made. Gulf of Mexico Base Flood Elevation +9-15 Unincorporated Areas of changes...

  12. 75 FR 31342 - Proposed Flood Elevation Determinations

    Science.gov (United States)

    2010-06-03

    ... flood insurance premium rates for new buildings and the contents in those buildings. DATES: Comments are... these elevations are made final, and for the contents in those buildings. Comments on any aspect of the..., Augusta, ME 04330. Perry County, Missouri, and Incorporated Areas Apple Creek At a dam/unnamed road +400...

  13. Asymptomatic proteinuria and elevated blood pressure among ...

    African Journals Online (AJOL)

    Background: Hypertension and proteinuria are known risk factors for cardiovascular disease and renal impairment. Early detection and treatment will reduce morbidity and mortality associated with them. Objective: To determine the prevalence of asymptomatic proteinuria with or without elevated blood pressure among ...

  14. Outcomes Following Traumatic Grain Elevator Injuries.

    Science.gov (United States)

    Tolefree, Sydnei; Truong, Anthony; Ward, Jeanette; Dong, Fanglong; Ablah, Elizabeth; Haan, James

    2017-01-01

    The absence of a comprehensive database of grain elevator-associated injuries hinders accurate evaluation of injury prevalence and may lead to discordant information about injury frequencies. The main purpose of this study was to identify the most common mechanisms of injury related to grain elevator events. Comparisons of hospital outcomes between patients who sustained traumatic injuries associated with grain elevators at Occupational Safety and Health Administration (OSHA)-regulated industrial sites versus those on OSHA-exempt farming operations were also made. A retrospective review was conducted of all patients' presenting with grain elevator-related injuries at a level-1 trauma center between January 1, 2003, and December 31, 2013. Data collected included demographics, mechanism of injury, injury severity, hospitalization details, and discharge disposition. Data were summarized, and comparisons were made between the groups. All patients (N = 18) in the study were male, with a mean age of 37 years. Falls and being caught in equipment each accounted for 27.8% of injuries. Among the 18 patients, there were a total of 37 injuries. The majority of injuries were either lower extremity (29.7%) or chest injuries (21.6%). The average hospital length of stay was 4 ± 4.5 days, and one patient required mechanical ventilation. There were no reported deaths. The literature reports entrapments as the leading cause of grain elevator-related injuries; however, this study found that falls and being caught in equipment were the most common mechanisms of injury. This suggests that a greater emphasis should be placed on fall prevention and equipment safety.

  15. Phylogenetically balanced evidence for structural and carbon isotope responses in plants along elevational gradients.

    Science.gov (United States)

    Zhu, Yuan; Siegwolf, Rolf T W; Durka, Walter; Körner, Christian

    2010-04-01

    We tested three hypotheses related to the functioning of mountain plants, namely their reproductive effort, leaf surface structure and effectiveness of CO(2) assimilation, using archive material from contrasting elevations. Analysis of elevational trends is at risk of suffering from two major biases: a phylogenetic bias (i.e. an elevational change in the abundance of taxonomic groups), and covariation of different environmental drivers (e.g. water, temperature, atmospheric pressure), which do not permit a mechanistic interpretation. We solved both problems in a subcontinental survey of elevational trends in key plant traits in the European Alps and the high Arctic (northern Sweden, Svalbard), using herbarium samples of 147 species belonging to the genera Carex, Saxifraga and Potentilla. We used both species and phylogenetically independent contrasts as data points. The analysis revealed enhanced reproductive efforts at higher elevation in insect-pollinated taxa (not in wind-pollinated taxa), no increase in leaf pubescence at high elevation (as is often assumed), and a strong correlation between (13)C discrimination and elevation. Alpine taxa operate at a smaller mesophyll resistance to CO(2) uptake relative to diffusive resistance (stomata). By comparison with congeneric low altitude polar taxa (low temperature, but high atmospheric pressure), the response could be attributed to the elevational decline in atmospheric pressure rather than temperature (a mean increase in delta(13)C by 1.4 per thousand km(-1)). The signal is consistent within and across genera and within species, suggesting rapid adjustment of leaf physiology to reduced partial pressure of CO(2). These results offer answers to long-debated issues of plant responses to high elevation life conditions.

  16. Cerebral Pulsatility Index Is Elevated in Patients with Elevated Right Atrial Pressure.

    Science.gov (United States)

    Lahiri, Shouri; Schlick, Konrad H; Padrick, Matthew M; Rinsky, Brenda; Gonzalez, Nestor; Jones, Heather; Mayer, Stephan A; Lyden, Patrick D

    2018-01-01

    Extracerebral venous congestion can precipitate intracranial hypertension due to obstruction of cerebral blood outflow. Conditions that increase right atrial pressure, such as hypervolemia, are thought to increase resistance to jugular venous outflow and contribute to cerebro-venous congestion. Cerebral pulsatility index (CPI) is considered a surrogate marker of distal cerebrovascular resistance and is elevated with intracranial hypertension. Thus, we sought to test the hypothesis that elevated right atrial pressure is associated with increased CPI compared to normal right atrial pressure. We retrospectively reviewed 61 consecutive patients with subarachnoid hemorrhage. We calculated CPI from transcranial Doppler studies and correlated these with echocardiographic measures of right atrial pressure. CPIs were compared from patients with elevated and normal right atrial pressure. There was a significant difference between CPI obtained from all patients with elevated right atrial pressure compared to those with normal right atrial pressure (P right and left hemispheric CPI from patients with both elevated and normal right atrial pressure. Patients with elevated right atrial pressure had significantly higher CPI compared to patients with normal right atrial pressure. These findings suggest that cerebro-venous congestion due to impaired jugular venous outflow may increase distal cerebrovascular resistance as measured by CPI. Since elevated CPI is associated with poor outcome in numerous neurological conditions, future studies are needed to elucidate the significance of these results in other populations. Copyright © 2017 by the American Society of Neuroimaging.

  17. Reducing elevator energy use: A comparison of posted feedback and reduced elevator convenience

    Science.gov (United States)

    Houten, Ron Van; Nau, Paul A.; Merrigan, Michael

    1981-01-01

    The effects of two different procedures for reducing elevator energy use were assessed using a multiple-baseline design. In the first procedure, feedback about the amount of energy consumed by the elevators each week was posted on each elevator door. Later, signs advocating the use of stairs to save energy and improve health were posted next to the feedback signs. In the second procedure, the time required to travel between floors was increased by adding a delay to the elevator door closing mechanisms. Results indicated that neither feedback alone nor feedback plus educational signs reduced the amount of energy consumed by the elevators. However, use of the door delay reduced consumption by one-third in all elevators. A second experiment replicated the effect of the door delay on energy consumption and, in addition, demonstrated that the door delay also produced a reduction in the number of persons using the elevator. The second experiment also showed that, following an initial period during which a full delay was in effect, a gradual reduction of the delay interval resulted in continued energy conservation. Reduced convenience as a general strategy for energy conservation is discussed. PMID:16795648

  18. Independent encoding of surface orientation and surface curvature.

    Science.gov (United States)

    Johnston, A; Passmore, P J

    1994-11-01

    Marr [(1982) Vision, San Francisco, Calif.: Freeman] proposed that we represent surface geometry in terms of a viewer-centred description of surface orientation and distance. This description is computed by a range of independent processing systems which take as input particular kinds of information present in images, like surface texture, shading, retinal disparity and motion parallax. The outputs of these modules are integrated in order to provide a unitary representation of the layout of visible surfaces. Higher order properties of surface geometry, like surface curvature, might be computed from this symbolic representation or might be encoded independently from the visual information available at the retinae. We measured surface slant and surface curvature discrimination thresholds for surface patches defined by shading, texture and retinal disparity as a function of the elevation of the illumination. We found that observers judgements about the curvature of local surface patches were too precise to be based on a symbolic representation of surface orientation and we conclude that surface curvature is computed directly from depth cues present in the retinal images.

  19. `Dem DEMs: Comparing Methods of Digital Elevation Model Creation

    Science.gov (United States)

    Rezza, C.; Phillips, C. B.; Cable, M. L.

    2017-12-01

    Topographic details of Europa's surface yield implications for large-scale processes that occur on the moon, including surface strength, modification, composition, and formation mechanisms for geologic features. In addition, small scale details presented from this data are imperative for future exploration of Europa's surface, such as by a potential Europa Lander mission. A comparison of different methods of Digital Elevation Model (DEM) creation and variations between them can help us quantify the relative accuracy of each model and improve our understanding of Europa's surface. In this work, we used data provided by Phillips et al. (2013, AGU Fall meeting, abs. P34A-1846) and Schenk and Nimmo (2017, in prep.) to compare DEMs that were created using Ames Stereo Pipeline (ASP), SOCET SET, and Paul Schenk's own method. We began by locating areas of the surface with multiple overlapping DEMs, and our initial comparisons were performed near the craters Manannan, Pwyll, and Cilix. For each region, we used ArcGIS to draw profile lines across matching features to determine elevation. Some of the DEMs had vertical or skewed offsets, and thus had to be corrected. The vertical corrections were applied by adding or subtracting the global minimum of the data set to create a common zero-point. The skewed data sets were corrected by rotating the plot so that it had a global slope of zero and then subtracting for a zero-point vertical offset. Once corrections were made, we plotted the three methods on one graph for each profile of each region. Upon analysis, we found relatively good feature correlation between the three methods. The smoothness of a DEM depends on both the input set of images and the stereo processing methods used. In our comparison, the DEMs produced by SOCET SET were less smoothed than those from ASP or Schenk. Height comparisons show that ASP and Schenk's model appear similar, alternating in maximum height. SOCET SET has more topographic variability due to its

  20. 30 CFR 75.1403-4 - Criteria-Automatic elevators.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Criteria-Automatic elevators. 75.1403-4 Section... Criteria—Automatic elevators. (a) The doors of automatic elevators should be equipped with interlocking switches so arranged that the elevator car will be immovable while any door is opened or unlocked, and...

  1. 29 CFR 1917.116 - Elevators and escalators.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Elevators and escalators. 1917.116 Section 1917.116 Labor... (CONTINUED) MARINE TERMINALS Terminal Facilities § 1917.116 Elevators and escalators. (a) “Elevator” means a...) No elevator or escalator with a defect which affects safety shall be used. (d) Elevator safety...

  2. Thermal Behavior of Cylindrical Buckling Restrained Braces at Elevated Temperatures

    Directory of Open Access Journals (Sweden)

    Elnaz Talebi

    2014-01-01

    Full Text Available The primary focus of this investigation was to analyze sequentially coupled nonlinear thermal stress, using a three-dimensional model. It was meant to shed light on the behavior of Buckling Restraint Brace (BRB elements with circular cross section, at elevated temperature. Such bracing systems were comprised of a cylindrical steel core encased in a strong concrete-filled steel hollow casing. A debonding agent was rubbed on the core’s surface to avoid shear stress transition to the restraining system. The numerical model was verified by the analytical solutions developed by the other researchers. Performance of BRB system under seismic loading at ambient temperature has been well documented. However, its performance in case of fire has yet to be explored. This study showed that the failure of brace may be attributed to material strength reduction and high compressive forces, both due to temperature rise. Furthermore, limiting temperatures in the linear behavior of steel casing and concrete in BRB element for both numerical and analytical simulations were about 196°C and 225°C, respectively. Finally it is concluded that the performance of BRB at elevated temperatures was the same as that seen at room temperature; that is, the steel core yields prior to the restraining system.

  3. Properties of Free-Machining Aluminum Alloys at Elevated Temperatures

    Science.gov (United States)

    Faltus, Jiří; Karlík, Miroslav; Haušild, Petr

    In areas close to the cutting tool the workpieces being dry machined could be heated up to 350°C and they may be impact loaded. Therefore it is of interest to study mechanical properties of corresponding materials at elevated temperatures. Free-machining alloys of Al-Cu and Al-Mg-Si systems containing Pb, Bi and Sn additions (AA2011, AA2111B, AA6262, and AA6023) were subjected to Charpy U notch impact test at the temperatures ranging from 20 to 350°C. The tested alloys show a sharp drop in notch impact strength KU at different temperatures. This drop of KU is caused by liquid metal embrittlement due to the melting of low-melting point dispersed phases which is documented by differential scanning calorimetry. Fracture surfaces of the specimens were observed using a scanning electron microscope. At room temperature, the fractures of all studied alloys exhibited similar ductile dimple fracture micromorphology, at elevated temperatures, numerous secondary intergranular cracks were observed.

  4. Structure Line Detection from LIDAR Point Clouds Using Topological Elevation Analysis

    Science.gov (United States)

    Lo, C. Y.; Chen, L. C.

    2012-07-01

    Airborne LIDAR point clouds, which have considerable points on object surfaces, are essential to building modeling. In the last two decades, studies have developed different approaches to identify structure lines using two main approaches, data-driven and modeldriven. These studies have shown that automatic modeling processes depend on certain considerations, such as used thresholds, initial value, designed formulas, and predefined cues. Following the development of laser scanning systems, scanning rates have increased and can provide point clouds with higher point density. Therefore, this study proposes using topological elevation analysis (TEA) to detect structure lines instead of threshold-dependent concepts and predefined constraints. This analysis contains two parts: data pre-processing and structure line detection. To preserve the original elevation information, a pseudo-grid for generating digital surface models is produced during the first part. The highest point in each grid is set as the elevation value, and its original threedimensional position is preserved. In the second part, using TEA, the structure lines are identified based on the topology of local elevation changes in two directions. Because structure lines can contain certain geometric properties, their locations have small relieves in the radial direction and steep elevation changes in the circular direction. Following the proposed approach, TEA can be used to determine 3D line information without selecting thresholds. For validation, the TEA results are compared with those of the region growing approach. The results indicate that the proposed method can produce structure lines using dense point clouds.

  5. A search profile for dwellings with elevated radon levels

    DEFF Research Database (Denmark)

    Damkjær, A.; Andersen, C.E.; Majborn, B.

    1996-01-01

    A search profile for dwellings with elevated radon levels has been employed to investigate possibly radon-prone areas in Denmark and to find houses suitable for radon mitigation studies. The profile is defined as dwellings which are single-family houses with slab-on-grade foundation or partly...... basement/slab-on-grade foundation built on either fractured granitic basement rocks, or fractured limestone. Clayey till areas were also included in the profile in order to confirm earlier findings. Three areas representing these surface geologies were selected for indoor radon measurements with CR-39...... track detectors, and a total of 200 houses matching the profile underwent radon measurements during the winter 1994-95. The distribution of the measured radon concentrations were found in most cases to comply with log-normal distributions. Measurements in the living rooms of houses in each of the three...

  6. Regional elevator survey : grain transportation & industry trends for Great Plains elevators

    Science.gov (United States)

    2001-08-01

    One potential means for gaining insight into the current state of the elevator industry, : and into expectations for future trends, is through a survey. The objective of this study is to profile the transportation and industry characteristics of the ...

  7. Plants with elevated levels of glucan

    Energy Technology Data Exchange (ETDEWEB)

    Pauly, Markus; Kraemer, Florian J.; Hake, Sarah

    2018-03-20

    The present disclosure relates to mutations in licheninase genes encoding polypeptides with decreased licheninase activity, which when expressed in plants results in elevated levels of glucan in the plants. In particular, the disclosure relates to licheninase nucleic acids and polypeptides related to glucan accumulation in plants, plants with reduced expression of a licheninase nucleic acid, and methods related to the generation of plants with increased glucan content in the cell walls of leaf tissue.

  8. Prevalence of elevated serum creatinine among treated ...

    African Journals Online (AJOL)

    A cut off mark of 1.5mg/dl was used to evaluate elevated serum creatinine levels. Results: There were 826patients with a male/female ratio of 1:1.32. Males were 356 (43.1%) and females 470 (56.9%). Among these patients, 118 (14.3%) had a serum creatinine value of over 1.5mg/dl, signifying renal disease. Conclusion: A ...

  9. Spatial and temporal characteristics of elevated temperatures in municipal solid waste landfills.

    Science.gov (United States)

    Jafari, Navid H; Stark, Timothy D; Thalhamer, Todd

    2017-01-01

    Elevated temperatures in waste containment facilities can pose health, environmental, and safety risks because they generate toxic gases, pressures, leachate, and heat. In particular, MSW landfills undergo changes in behavior that typically follow a progression of indicators, e.g., elevated temperatures, changes in gas composition, elevated gas pressures, increased leachate migration, slope movement, and unusual and rapid surface settlement. This paper presents two MSW landfill case studies that show the spatial and time-lapse movements of these indicators and identify four zones that illustrate the transition of normal MSW decomposition to the region of elevated temperatures. The spatial zones are gas front, temperature front, and smoldering front. The gas wellhead temperature and the ratio of CH 4 to CO 2 are used to delineate the boundaries between normal MSW decomposition, gas front, and temperature front. The ratio of CH 4 to CO 2 and carbon monoxide concentrations along with settlement strain rates and subsurface temperatures are used to delineate the smoldering front. In addition, downhole temperatures can be used to estimate the rate of movement of elevated temperatures, which is important for isolating and containing the elevated temperature in a timely manner. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Dominant factors controlling glacial and interglacial variations in the treeline elevation in tropical Africa.

    Science.gov (United States)

    Wu, Haibin; Guiot, Joël; Brewer, Simon; Guo, Zhengtang; Peng, Changhui

    2007-06-05

    The knowledge of tropical palaeoclimates is crucial for understanding global climate change, because it is a test bench for general circulation models that are ultimately used to predict future global warming. A longstanding issue concerning the last glacial maximum in the tropics is the discrepancy between the decrease in sea-surface temperatures reconstructed from marine proxies and the high-elevation decrease in land temperatures estimated from indicators of treeline elevation. In this study, an improved inverse vegetation modeling approach is used to quantitatively reconstruct palaeoclimate and to estimate the effects of different factors (temperature, precipitation, and atmospheric CO(2) concentration) on changes in treeline elevation based on a set of pollen data covering an altitudinal range from 100 to 3,140 m above sea level in Africa. We show that lowering of the African treeline during the last glacial maximum was primarily triggered by regional drying, especially at upper elevations, and was amplified by decreases in atmospheric CO(2) concentration and perhaps temperature. This contrasts with scenarios for the Holocene and future climates, in which the increase in treeline elevation will be dominated by temperature. Our results suggest that previous temperature changes inferred from tropical treeline shifts may have been overestimated for low-CO(2) glacial periods, because the limiting factors that control changes in treeline elevation differ between glacial and interglacial periods.

  11. Experimental prototype of an electric elevator

    Science.gov (United States)

    Gaiceanu, M.; Epure, S.; Ciuta, S.

    2016-08-01

    The main objective is to achieve an elevator prototype powered by a three-phase voltage system via a bidirectional static power converter ac-ac with regenerating capability. In order to diminish the power size of the electric motor up to 1/3 of rated power, the elevator contains two carriages of the same weight, one serving as the payload, and the other as counterweight. Before proper operation of the static power converter, the capacitor must be charged at rated voltage via a precharge circuit. At the moment of stabilizing the DC voltage at nominal value, the AC-AC power converter can operates in the proper limits. The functions of the control structure are: the load control task, speed and torque controls. System includes transducers for current measuring, voltage sensors and encoder. As reserve power sources the hybrid battery-photovoltaic panels are used. The control voltage is modulated by implementing four types of pulse width modulations: sinusoidal, with reduced commutation, third order harmonic insertion, and the space vector modulation. Therefore, the prototype could operates with an increased efficiency, in spite of the existing ones. The experimental results confirm the well design of the chosen solution. The control solution assures bidirectional power flow control, precharge control, and load control and it is implemented on a digital signal processor. The elevator capacity is between 300-450 kg, and it is driven by using a 1.5 kW three-phase asynchronous machine.

  12. Endoscopic laryngeal web formation for pitch elevation.

    Science.gov (United States)

    Anderson, Jennifer

    2007-02-01

    Endoscopic laryngeal web formation has been used to elevate the speaking voice, primarily in male to female transsexuals as part of gender reassignment intervention. The goal of this article is to review the literature regarding surgical treatment for pitch elevation and to describe a novel method of laryngeal web formation. The results of this technique are also reported in a series of six patients. All patients were assessed and treated at the St. Michael's Hospital Voice Disorders Clinic, a tertiary referral centre for voice disorders. Pre- and postoperative voice recordings, acoustic analysis, and videostroboscopic examinations were performed in this series. The acoustic data collected included isolated vowel samples, a reading task, and a modified voice range profile. The patients all underwent successful endoscopic web formation with a Gelfoam augmentation technique. The voice results collected at least 6 months after vocal fold web formation demonstrate a dramatic increase in the habitual speaking fundamental frequency. This new modification for endoscopic web formation has been shown to be a successful procedure for permanent elevation of pitch with little or no morbidity.

  13. Rangeland -- plant response to elevated CO2

    International Nuclear Information System (INIS)

    Owensby, C.E.; Coyne, P.I.; Ham, J.M.; Parton, W.; Rice, C.; Auen, L.M.; Adam, N.

    1993-01-01

    Plots of a tallgrass prairie ecosystem were exposed to ambient and twice-ambient CO 2 concentrations in open-top chambers and compared to unchambered ambient CO 2 plots during the entire growing season from 1989 through 1992. Relative root production among treatments was estimated using root ingrowth bags which remained in place throughout the growing season. Latent heat flux was simulated with and without water stress. Botanical composition was estimated annuallyin all treatments. Open-top chambers appeared to reduce latent heat flux and increase water use efficiency similar to elevated CO 2 when water stress was not severe, but under severe water stress, chamber effect on water use efficiency was limited. In natural ecosystems with periodic moisture stress, increased water use efficiency under elevated CO 2 apparently would have a greater impact on productivity than photosynthetic pathway. Root ingrowth biomass was greater in 1990 and 1991 on elevated CO 2 plots compared to ambient or chambered-ambient plots. In 1992, there was no difference in root ingrowth biomass among treatments

  14. Elevers læring og progression

    DEFF Research Database (Denmark)

    praksisbaserede anbefalinger til, hvordan data om elevernes progression kan indsamles, sammenstilles, vises og understøtte elevernes udvikling, så alle elever bliver så dygtige, som de kan. Rapporten består af et resumé af en forskningskortlægning af danske og internationale studier af, hvordan man måler læring...... og progression, og hvordan fagprofessionelle kan arbejde med elevdata for at understøtte elevers læring og progression. Derefter følger opsamling på en spørgeskemaundersøgelse blandt private leverandører af digitale læremidler til folkeskolen og resultaterne af en erfaringsopsamling blandt lærere......, elever og forældre. Endelig præsenteres erfaringerne med et konkret udviklingsarbejde på en række områder, hvor elevdata spiller en væsentlig rolle samt fagdidaktiske overvejelser om fagprofessionelles brug af elevdata. På baggrund af undersøgelsen præsenteres anbefalinger til overordnede systembehov...

  15. Elevated CO2 stimulates marsh elevation gain, counterbalancing sea-level rise

    Science.gov (United States)

    Langley, J.A.; McKee, K.L.; Cahoon, D.R.; Cherry, J.A.; Megonigala, J.P.

    2009-01-01

    Tidal wetlands experiencing increased rates of sea-level rise (SLR) must increase rates of soil elevation gain to avoid permanent conversion to open water. The maximal rate of SLR that these ecosystems can tolerate depends partly on mineral sediment deposition, but the accumulation of organic matter is equally important for many wetlands. Plant productivity drives organic matter dynamics and is sensitive to global change factors, such as rising atmospheric CO2 concentration. It remains unknown how global change will influence organic mechanisms that determine future tidal wetland viability. Here, we present experimental evidence that plant response to elevated atmospheric [CO2] stimulates biogenic mechanisms of elevation gain in a brackish marsh. Elevated CO2 (ambient + 340 ppm) accelerated soil elevation gain by 3.9 mm yr−1in this 2-year field study, an effect mediated by stimulation of below-ground plant productivity. Further, a companion greenhouse experiment revealed that the CO2 effect was enhanced under salinity and flooding conditions likely to accompany future SLR. Our results indicate that by stimulating biogenic contributions to marsh elevation, increases in the greenhouse gas, CO2, may paradoxically aid some coastal wetlands in counterbalancing rising seas.

  16. Minimal surfaces

    CERN Document Server

    Dierkes, Ulrich; Sauvigny, Friedrich; Jakob, Ruben; Kuster, Albrecht

    2010-01-01

    Minimal Surfaces is the first volume of a three volume treatise on minimal surfaces (Grundlehren Nr. 339-341). Each volume can be read and studied independently of the others. The central theme is boundary value problems for minimal surfaces. The treatise is a substantially revised and extended version of the monograph Minimal Surfaces I, II (Grundlehren Nr. 295 & 296). The first volume begins with an exposition of basic ideas of the theory of surfaces in three-dimensional Euclidean space, followed by an introduction of minimal surfaces as stationary points of area, or equivalently

  17. Elevation change and remote-sensing mass-balance methods on the Greenland ice sheet

    DEFF Research Database (Denmark)

    Ahlstrøm, Andreas P.; Reeh, Niels; Christensen, Erik Lintz

    The mass balance of the Greenland Ice Sheet is virtually impossible to obtain with traditional ground-based methods alone due to its vast size. It is thus desirable to develop mass-balance methods depending on remote sensing instead and this field has experienced a dramatic development within...... the last decade. Large amounts of data have been collected from satellite and airborne platforms, yielding surface elevation changes and surface velocity fields. Here we present data from the Greenland Ice-Sheet margin acquired with a new small-scale airborne system, designed for regional high......-density coverage. During campaigns in 2000, 2003 and 2005, we have collected and processed ice-sheet surface elevation and ice-thickness data, acquired with a laser altimeter and a 60~MHz ice-penetrating radar. Both instruments were mounted on a small Twin-Otter aircraft which were positioned using three onboard...

  18. Elevational gradient in clutch size of Red-faced Warblers

    Science.gov (United States)

    Dillon, Kristen G.; Conway, Courtney J.

    2015-01-01

    Our understanding of life history evolution has benefited from debates regarding the underlying causes, and geographic ubiquity, of spatial patterns in avian clutch sizes. Past studies have revealed that birds lay smaller clutch sizes at higher elevation. However, in most previous studies, investigators have failed to adequately control for elevational differences in breeding phenology. To better understand the elevational gradient in avian clutch size, we need to know how clutch size changes across the entire elevational breeding range of a species (i.e., the shape of the relationship between elevation and clutch size), and whether the elevational gradient in clutch size is merely an artifact of elevational gradients in breeding phenology or breeding season length. We examined the relationship between breeding elevation and clutch size of Red-faced Warblers (Cardellina rubrifrons) along a 1000-m elevational gradient in Arizona. Our objectives were to determine how clutch size changed with elevation, and if the relationship between clutch size and elevation merely reflected elevational changes in breeding season length or phenology. The proportion of 5-egg clutches decreased and the proportion of 3- and 4-egg clutches increased non-linearly with increasing elevation, even after controlling for the elevational gradient in nest initiation date. Thus, average clutch size declined across the elevational breeding range of Red-faced Warblers, but this decline was not due to elevational variation in breeding phenology. Timing of breeding changed, but the duration of the breeding season did not change appreciably across the elevational gradient. Hence, elevational differences in breeding season length or breeding phenology cannot explain why Red-faced Warblers (and perhaps other birds) breeding at higher elevations have smaller clutches.

  19. The influence of elevated feed stalls on feeding behaviour of lactating dairy cows

    Directory of Open Access Journals (Sweden)

    Barbara Benz

    2014-10-01

    Full Text Available The performance level of high yielding cows can only be guaranteed by high quality forage and high feed intake. An about 15–20 cm elevated and 160 cm long feed stall with rubber flooring doesn’t only offer undisturbed meals but also a yielding and dry standing surface. In a pilot stable with 130 dairy cows (German Simmental the feeding alley was subsequently equipped with elevated feed stalls. The results show that animals frequented the feeding barn less often while the duration of single meals prolonged. The specific behavioural changes differed depending on milk yield and number of lactation.

  20. Creating high-resolution digital elevation model using thin plate spline interpolation and Monte Carlo simulation

    International Nuclear Information System (INIS)

    Pohjola, J.; Turunen, J.; Lipping, T.

    2009-07-01

    In this report creation of the digital elevation model of Olkiluoto area incorporating a large area of seabed is described. The modeled area covers 960 square kilometers and the apparent resolution of the created elevation model was specified to be 2.5 x 2.5 meters. Various elevation data like contour lines and irregular elevation measurements were used as source data in the process. The precision and reliability of the available source data varied largely. Digital elevation model (DEM) comprises a representation of the elevation of the surface of the earth in particular area in digital format. DEM is an essential component of geographic information systems designed for the analysis and visualization of the location-related data. DEM is most often represented either in raster or Triangulated Irregular Network (TIN) format. After testing several methods the thin plate spline interpolation was found to be best suited for the creation of the elevation model. The thin plate spline method gave the smallest error in the test where certain amount of points was removed from the data and the resulting model looked most natural. In addition to the elevation data the confidence interval at each point of the new model was required. The Monte Carlo simulation method was selected for this purpose. The source data points were assigned probability distributions according to what was known about their measurement procedure and from these distributions 1 000 (20 000 in the first version) values were drawn for each data point. Each point of the newly created DEM had thus as many realizations. The resulting high resolution DEM will be used in modeling the effects of land uplift and evolution of the landscape in the time range of 10 000 years from the present. This time range comes from the requirements set for the spent nuclear fuel repository site. (orig.)

  1. Inter and intra-specific variation in photosynthetic acclimation response to long term exposure of elevated carbon dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Wilkinson, M. [Univ. of Essex, Colchester (United Kingdom)]|[Writtle Coll. (United Kingdom)

    1996-08-01

    The response of intra and interspecific variation in photosynthetic acclimation to growth at elevated atmospheric CO{sub 2} concentration (600{micro}mol mol-l) in six important grassland species was investigated. Plants were grown in a background sward of Lolium perenne and measurements were made after four years of growth at elevated C{sub a}. Elevated CO{sub 2} was maintained using a FACE (Free-Air Carbon Enrichment) system. Significant intra and interspecific variation in acclimation response was demonstrated. The response of adaxial and abaxial stomatal conductance to elevated CO{sub 2} was also investigated. The stomatal conductance of both the adaxial and abaxial leaf surfaces was found to be reduced by elevated C{sub a}. Significant asymmetric responses in stomatal conductance was demonstrated in D. glomerata and T. pratense. Analysis of stomatal indices and densities indicated that the observed reductions in stomatal conductance were probably the result of changes in stomatal aperture.

  2. Forecasting landscape effects of Mississippi River diversions on elevation and accretion in Louisiana deltaic wetlands under future environmental uncertainty scenarios

    Science.gov (United States)

    Wang, Hongqing; Steyer, Gregory D.; Couvillion, Brady R.; John M. Rybczyk,; Beck, Holly J.; William J. Sleavin,; Ehab A. Meselhe,; Mead A. Allison,; Ronald G. Boustany,; Craig J. Fischenich,; Victor H. Rivera-Monroy,

    2014-01-01

    Large sediment diversions are proposed and expected to build new wetlands to alleviate the extensive wetland loss (5,000 km2) affecting coastal Louisiana during the last 78 years. Current assessment and prediction of the impacts of sediment diversions have focused on the capture and dispersal of both water and sediment on the adjacent river side and the immediate outfall marsh area. However, little is known about the effects of sediment diversions on existing wetland surface elevation and vertical accretion dynamics in the receiving basin at the landscape scale. In this study, we used a spatial wetland surface elevation model developed in support of Louisiana's 2012 Coastal Master Plan to examine such landscape-scale effects of sediment diversions. Multiple sediment diversion projects were incorporated in the model to simulate surface elevation and vertical accretion for the next 50 years (2010-2060) under two environmental (moderate and less optimistic) scenarios. Specifically, we examined landscape-scale surface elevation and vertical accretion trends under diversions with different geographical locations, diverted discharge rates, and geomorphic characteristics of the receiving basin. Model results indicate that small diversions ( 1,500 m3 s-1) are required to achieve landscape-level benefits to promote surface elevation via vertical accretion to keep pace with rising sea level.

  3. Rumble surfaces

    CSIR Research Space (South Africa)

    National Institute for Transport and Road

    1977-01-01

    Full Text Available Rumble surfaces are intermittent short lengths of coarse-textured road surfacings on which vehicle tyres produce a rumbling sound. used in conjunction with appropriate roadsigns and markings, they can reduce accidents on rural roads by alerting...

  4. Surface thermodynamics

    International Nuclear Information System (INIS)

    Garcia-Moliner, F.

    1975-01-01

    Basic thermodynamics of a system consisting of two bulk phases with an interface. Solid surfaces: general. Discussion of experimental data on surface tension and related concepts. Adsorption thermodynamics in the Gibbsian scheme. Adsorption on inert solid adsorbents. Systems with electrical charges: chemistry and thermodynamics of imperfect crystals. Thermodynamics of charged surfaces. Simple models of charge transfer chemisorption. Adsorption heat and related concepts. Surface phase transitions

  5. Hurricane Wilma's impact on overall soil elevation and zones within the soil profile in a mangrove forest

    Science.gov (United States)

    Whelan, K.R.T.; Smith, T. J.; Anderson, G.H.; Ouellette, M.L.

    2009-01-01

    Soil elevation affects tidal inundation period, inundation frequency, and overall hydroperiod, all of which are important ecological factors affecting species recruitment, composition, and survival in wetlands. Hurricanes can dramatically affect a site's soil elevation. We assessed the impact of Hurricane Wilma (2005) on soil elevation at a mangrove forest location along the Shark River in Everglades National Park, Florida, USA. Using multiple depth surface elevation tables (SETs) and marker horizons we measured soil accretion, erosion, and soil elevation. We partitioned the effect of Hurricane Wilma's storm deposit into four constituent soil zones: surface (accretion) zone, shallow zone (0–0.35 m), middle zone (0.35–4 m), and deep zone (4–6 m). We report expansion and contraction of each soil zone. Hurricane Wilma deposited 37.0 (± 3.0 SE) mm of material; however, the absolute soil elevation change was + 42.8 mm due to expansion in the shallow soil zone. One year post-hurricane, the soil profile had lost 10.0 mm in soil elevation, with 8.5 mm of the loss due to erosion. The remaining soil elevation loss was due to compaction from shallow subsidence. We found prolific growth of new fine rootlets (209 ± 34 SE g m−2) in the storm deposited material suggesting that deposits may become more stable in the near future (i.e., erosion rate will decrease). Surficial erosion and belowground processes both played an important role in determining the overall soil elevation. Expansion and contraction in the shallow soil zone may be due to hydrology, and in the middle and bottom soil zones due to shallow subsidence. Findings thus far indicate that soil elevation has made substantial gains compared to site specific relative sea-level rise, but data trends suggest that belowground processes, which differ by soil zone, may come to dominate the long term ecological impact of storm deposit.

  6. Continental extension, magmatism and elevation; formal relations and rules of thumb

    Science.gov (United States)

    Lachenbruch, A.H.; Morgan, P.

    1990-01-01

    surface maintained 2 1 2km below sea level (e.g., an ocean ridge) B is about 5 km; for continental extension the ratio may be much greater. The frequent association of volcanism with continental extension, the high elevation (and buoyancy) of some appreciably extended terrains, and the oceanic spreading analog all suggest that magmatism may play an important role in continental extension. Better estimates of total extension and elevation change in extended regions can help to identify that role. ?? 1990.

  7. Enhanced ultrasonic focusing and temperature elevation via a therapeutic ultrasonic transducer with sub-wavelength periodic structure

    Science.gov (United States)

    Li, Chenghai; Yang, Yanye; Guo, Xiasheng; Tu, Juan; Huang, Pintong; Li, Faqi; Zhang, Dong

    2017-07-01

    In this paper, we report a therapeutic ultrasonic transducer with a sub-wavelength periodic structure, by which ultrasonic focusing and temperature elevation have been significantly enhanced compared to a conventional concave transducer with the same size. Enhanced acoustic focusing was demonstrated by both measuring and simulating acoustic pressure and temperature elevation. Compared to the conventional concave transducer, the proposed transducer exhibited stronger capacity in elevating acoustic pressure and temperature rise in the focal region, in which extraordinary acoustic transmission close to Wood's anomaly could be modulated by the spherically curved surface. This work is believed to possess great clinical potential in the safe and efficient application of ultrasonic therapy.

  8. Evaluation of the Global Multi-Resolution Terrain Elevation Data 2010 (GMTED2010) using ICESat geodetic control

    Science.gov (United States)

    Carabajal, C.C.; Harding, D.J.; Boy, J.-P.; Danielson, Jeffrey J.; Gesch, D.B.; Suchdeo, V.P.

    2011-01-01

    Supported by NASA's Earth Surface and Interior (ESI) Program, we are producing a global set of Ground Control Points (GCPs) derived from the Ice, Cloud and land Elevation Satellite (ICESat) altimetry data. From February of 2003, to October of 2009, ICESat obtained nearly global measurements of land topography (?? 86?? latitudes) with unprecedented accuracy, sampling the Earth's surface at discrete ???50 m diameter laser footprints spaced 170 m along the altimetry profiles. We apply stringent editing to select the highest quality elevations, and use these GCPs to characterize and quantify spatially varying elevation biases in Digital Elevation Models (DEMs). In this paper, we present an evaluation of the soon to be released Global Multi-resolution Terrain Elevation Data 2010 (GMTED2010). Elevation biases and error statistics have been analyzed as a function of land cover and relief. The GMTED2010 products are a large improvement over previous sources of elevation data at comparable resolutions. RMSEs for all products and terrain conditions are below 7 m and typically are about 4 m. The GMTED2010 products are biased upward with respect to the ICESat GCPs on average by approximately 3 m. ?? 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).

  9. [Diagnostic capability of carcinoembryonic antigen elevation].

    Science.gov (United States)

    Cerezo Ruiz, Antonio; Rosa Jiménez, Francisco; Lobón Hernández, José Antonio; Gómez Jiménez, Francisco Javier

    2014-12-01

    There is little information on the oncologic diagnostic accuracy of carcinoembryonic antigen (CEA) levels more than 3-fold above normal. To determine the prevalence of underlying cancer in patients with mild CEA elevation and the mean cost per patient of CEA determination. A retrospective study was carried out in all patients with CEA elevation (3-10 ng/ml) and suspicion of cancer referred to the gastroenterology or internal medicine outpatient units from 2001 to 2007. We studied 100 patients (60 men and 40 women), with a mean age of 67.4 ± 14.2 years and baseline CEA of 5.8 ± 1.7 ng/ml. The most important symptoms and signs were laboratory abnormalities (19 patients [19%]). Cancer was diagnosed in 4 patients (one gastric, 2 lung and one colon). Among patients without malignancies, 49 patients (49%) had no related processes, and 47 (47%) had benign diseases. During follow-up, one laryngeal cancer, one acute myeloid leukemia, and one colon cancer were detected (54.3 ± 24.6 months). We found no differences between baseline CEA levels in patients with and without cancer (6.6 ± 2.4 vs. 5.8 ± 1.7 ng/ml, p = 0.2). The mean cost per patient was 503.6 ± 257.6 €. Cancer was detected in a small proportion (7%) of patients with mild CEA elevation. The study of these patients is directly and indirectly associated with a not inconsiderable cost. Copyright © 2014 Elsevier España, S.L.U. and AEEH y AEG. All rights reserved.

  10. Cardiac Troponin I elevation after epileptic seizure

    Directory of Open Access Journals (Sweden)

    Sieweke Nicole

    2012-07-01

    Full Text Available Abstract Background Cardiac troponin-I (cTNI is highly specific biomarker to prove myocardial damage, e.g. in acute coronary syndrome (ACS. However, it occurs in other conditions as well. We therefore analysed cTNI increase in patients after generalized convulsive seizure. Methods Consecutive patients admitted with acute generalized convulsive seizure were included in case of cTNI measurement on admission. Among 898 selected cases, 53 patients were referred secondary to our department; in 845 cases cTNI measurements on admission were available. In case of multiple admissions (81 cases, only the first admission entered our analysis. In 17 patients elevated cTNI was determined due to ACS; in one patient a myocarditis was found. 5 patients suffered of relevant renal insufficiency. Finally 741 patients were included in the analysis. A cTNI cut-off level of ≥ 0.1 ng/ml was considered. Factors associated with a cTNI increase were analysed subsequently. Results The mean age of the study population (n = 741 was 47.8 years (SD ± 18.6, 40.9% were female. In 50 patients (6.7% a cTNI elevation of unknown origin was found; no obvious cardiac involvement could be detected in these patients who all remained asymptomatic. A vascular risk profile (including at least hypertension, hypercholesterolemia or diabetes (OR = 3.62; CI: 1.59 to 8.21; p = 0.001 and elevated creatine kinase on admission (OR = 2.36; CI: 1.26 to 4.39; p = 0.002 were independent factors associated with cTNI release. Conclusion cTNI release occurs in patients with generalized convulsive seizure with predominance in patients with vascular risk profile.

  11. ST-elevations-myokardieinfarkt efter terapeutisk adrenalininjektion

    DEFF Research Database (Denmark)

    Rømhild Davidsen, Jesper; Lambrechtsen, Jess; Egstrup, Kenneth

    2006-01-01

    A case of acute myocardial infarction (AMI) following accidental iatrogenic overdose by adrenaline injection is described in a male aged 55 years. This patient was given 1 mg of adrenaline due to anaphylactic symptoms. Afterwards he presented with angina pectoris, dyspnoea and ST-segment elevation...... in the ECG. Plasma TnT and CK-MB were raised. A coronary angiography revealed a 66% stenosis of RCA. This patient had an asymptomatic RCA stenosis that probably became symptomatic due to coronary artery spasm related to adrenaline injection and thereby presented symptoms and signs of AMI....

  12. [Functional and mechanical anatomy of arm elevation].

    Science.gov (United States)

    Gagey, O; Bonfait, H; Gillot, C; Mazas, F

    1988-01-01

    Experimental work on the functional anatomy of the shoulder has involved a study of the conditions involved in elevation of the arm. Movements of the upper limb are organised round a very special alignment of the scapulo-humeral joint whose geometric features and exact position have been determined. The ligaments of the joint play a major role in the controlling the attainment of this alignment. The value of this alignment in the physiology of the shoulder is demonstrated. A new terminology of shoulder movement is suggested.

  13. Elevated environmental temperature and methamphetamine neurotoxicity

    International Nuclear Information System (INIS)

    Miller, Diane B.; O'Callaghan, James P.

    2003-01-01

    Amphetamines have been of considerable research interest for the last several decades. More recent work has renewed interest in the role of ambient temperature in both the toxicity and neurotoxicity of these drugs. We have determined that the striatal dopaminergic neurotoxicity observed in the mouse is linked in some fashion to both body and environmental temperature. Most studies of d-methamphetamine (d-METH) neurotoxicity are conducted at standard laboratory ambient temperatures (e.g., ∼21-22 deg. C) and utilizing a repeated dosage regimen (e.g., three to four injections spaced 2 h apart). A lowering of the ambient temperature provides neuro protection, while an elevation increases neurotoxicity. d-METH causes long-term depletions of triatal dopamine (DA) that are accompanied by other changes that are indicative of nerve terminal degeneration. These include argyrophilia, as detected by silver degeneration stains, and an elevation in glial fibrillary acidic protein (GFAP), a marker of reactive gliosis in response to injury, as well as a long-term decrease in tyrosine hydroxylase (TH) protein levels. here we show that increasing the ambient temperature during and for some time following dosing increases the neurotoxicity of d-METH. Mice (female 57BL6/J) given a single dosage of d-METH (20 mg/kg s.c.) and maintained at the usual laboratory ambient temperature show minimal striatal damage (an ∼15% depletion of DA and an ∼ 86% increase in GFAP). substantial striatal damage (e.g., an ∼70% depletion of DA and an ∼200% elevation in GFAP) was induced by this regimen if mice were maintained at 27 deg. C for 24 or 72 h following dosing. An increase in neurotoxicity was also apparent in mice kept at an elevated temperature for only 5 or 9 h, but keeping animals at 27 deg. C for 24 or 72 h was the most effective in increasing the neurotoxicity of d-METH. Our data show how a relatively minor change in ambient temperature can have a major impact on the degree of

  14. Study on the Influence of Elevation of Tailing Dam on Stability

    Science.gov (United States)

    Wan, Shuai; Wang, Kun; Kong, Songtao; Zhao, Runan; Lan, Ying; Zhang, Run

    2017-12-01

    This paper takes Yunnan as the object of a tailing, by theoretical analysis and numerical calculation method of the effect of seismic load effect of elevation on the stability of the tailing, to analyse the stability of two point driven safety factor and liquefaction area. The Bishop method is adopted to simplify the calculation of dynamic safety factor and liquefaction area analysis using comparison method of shear stress to analyse liquefaction, so we obtained the influence of elevation on the stability of the tailing. Under the earthquake, with the elevation increased, the safety coefficient of dam body decreases, shallow tailing are susceptible to liquefy. Liquefaction area mainly concentrated in the bank below the water surface, to improve the scientific basis for the design and safety management of the tailing.

  15. A global digital elevation model - GTOP030

    Science.gov (United States)

    1999-01-01

    GTOP030, the U.S. Geological Survey's (USGS) digital elevation model (DEM) of the Earth, provides the flrst global coverage of moderate resolution elevation data.  The original GTOP30 data set, which was developed over a 3-year period through a collaborative effort led by the USGS, was completed in 1996 at the USGS EROS Data Center in Sioux Falls, South Dakota.  The collaboration involved contributions of staffing, funding, or source data from cooperators including the National Aeronautics and Space Administration (NASA), the United Nations Environment Programme Global Resource Information Database (UNEP/GRID), the U.S. Agency for International Development (USAID), the Instituto Nacional de Estadistica Geografia e Informatica (INEGI) of Mexico, the Geographical Survey Institute (GSI) of Japan, Manaaki Whenua Landcare Research of New Zealand, and the Scientific Committee on Antarctic Research (SCAR). In 1999, work was begun on an update to the GTOP030 data set. Additional data sources are being incorporated into GTOP030 with an enhanced and improved data set planned for release in 2000.

  16. CANDU fuel compression tests at elevated temperatures

    International Nuclear Information System (INIS)

    Koehn, E.; Chan, J.K.; Langman, V.J.; Hadaller, G.I.; Fortman, R.A.

    1995-01-01

    An inlet header large break loss of coolant accident (LOCA) in CANDU reactors with fuelling against flow can cause the fuel to shift in the channels with a consequent reactivity insertion. This results in an increased fuel power transient, and a potential increase in the mialyzed consequences for such events. As the reactor's age and the channel axial gaps increase, the magnitude of the predicted power u-dmient increases. A design solution to reduce the power transient is to limit the amount of fuel movement by reducing the channel axial gap. This solution was implemented into Ontario Hydro's Bruce B and Darlington reactors. A consequence of a reduced channel axial gap is the potential for the fuel column axial expansion to become constrained by the channel end components in large break LOCAs. This experimental program investigated the effects of pellet cracking and elevated sheath temperatures on the ability of the fuel elements, of the 37-element bundle design, to sustain axial loads. The unirradiated fuel elements tested were either in the as-received condition or with the U0 2 fuel pellets cracked in a mechanical process to simulate the effect of inufflation. The load deformation characteristics demonstrated that, for a given amount of axial compression. the loads sustainable by the elements at elevated sheath temperatures were low. As a result. excess axial expansion would be easily accommodated without further challenge to pressure tube integrity. (author)

  17. Elevation uncertainty in coastal inundation hazard assessments

    Science.gov (United States)

    Gesch, Dean B.; Cheval, Sorin

    2012-01-01

    Coastal inundation has been identified as an important natural hazard that affects densely populated and built-up areas (Subcommittee on Disaster Reduction, 2008). Inundation, or coastal flooding, can result from various physical processes, including storm surges, tsunamis, intense precipitation events, and extreme high tides. Such events cause quickly rising water levels. When rapidly rising water levels overwhelm flood defenses, especially in heavily populated areas, the potential of the hazard is realized and a natural disaster results. Two noteworthy recent examples of such natural disasters resulting from coastal inundation are the Hurricane Katrina storm surge in 2005 along the Gulf of Mexico coast in the United States, and the tsunami in northern Japan in 2011. Longer term, slowly varying processes such as land subsidence (Committee on Floodplain Mapping Technologies, 2007) and sea-level rise also can result in coastal inundation, although such conditions do not have the rapid water level rise associated with other flooding events. Geospatial data are a critical resource for conducting assessments of the potential impacts of coastal inundation, and geospatial representations of the topography in the form of elevation measurements are a primary source of information for identifying the natural and human components of the landscape that are at risk. Recently, the quantity and quality of elevation data available for the coastal zone have increased markedly, and this availability facilitates more detailed and comprehensive hazard impact assessments.

  18. Engineering Clostridia Neurotoxins with elevated catalytic activity.

    Science.gov (United States)

    Guo, Jiubiao; Pan, Xuehua; Zhao, Yanxiang; Chen, Sheng

    2013-11-01

    BoNT/B and TeNT cleave substrate VAMP2 at the same scissile bond, yet these two toxins showed different efficiency on substrate hydrolysis and had different requirements for the recognition of P2' site of VAMP2, E(78). These differences may be due to their different composition of their substrate recognition pockets in the active site. Swapping of LC/T S1' pocket residue, L(230), with the corresponding isoleucine in LC/B increased LC/T activity by ∼25 fold, while swapping of LC/B S1' pocket residue, S(201), with the corresponding proline in LC/T increased LC/B activity by ∼10 fold. Optimization of both S1 and S1' pocket residues of LC/T, LC/T (K(168)E, L(230)I) elevated LC/T activity by more than 100-fold. The highly active LC/T derivative engineered in this study has the potential to be used as a more effective tool to study mechanisms of exocytosis in central neuron. The LC/B derivative with elevated activity has the potential to be developed into novel therapy to minimize the impact of immunoresistance during BoNT/B therapy. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Elevated carboxyhemoglobin: sources of carbon monoxide exposure.

    Science.gov (United States)

    Buchelli Ramirez, Herminia; Fernández Alvarez, Ramón; Rubinos Cuadrado, Gemma; Martinez Gonzalez, Cristina; Rodriguez Jerez, Francisco; Casan Clara, Pere

    2014-11-01

    Inhalation of carbon monoxide (CO) can result in poisoning, with symptoms ranging from mild and nonspecific to severe, or even death. CO poisoning is often underdiagnosed because exposure to low concentrations goes unnoticed, and threshold values for normal carboxyhemoglobin vary according to different authors. The aim of our study was to analyze carboxyhemoglobin (COHb) levels in an unselected population and detect sources of CO exposure In a cross-sectional descriptive study, we analyzed consecutive arterial blood gas levels processed in our laboratory. We selected those with COHb≥2.5% in nonsmokers and ≥5% in smokers. In these cases a structured telephone interview was conducted. Elevated levels of COHb were found in 64 (20%) of 306 initial determinations. Of these, data from 51 subjects aged 65±12 years, 31 (60%) of which were men, were obtained. Mean COHb was 4.0%. Forty patients (78%) were non-smokers with mean COHb of 3.2%, and 11 were smokers with COHb of 6.7%. In 45 patients (88.2%) we detected exposure to at least one source of ambient CO other than cigarette smoke. A significant proportion of individuals from an unselected sample had elevated levels of COHb. The main sources of CO exposure were probably the home, so this possibility should be explored. The population should be warned about the risks and encouraged to take preventive measures. Copyright © 2013 SEPAR. Published by Elsevier Espana. All rights reserved.

  20. Organic matter composition and substrate diversity under elevated CO2 in the Mojave Desert

    Science.gov (United States)

    Tfaily, M. M.; Hess, N. J.; Koyama, A.; Evans, R. D.

    2016-12-01

    Little is known about how rising atmospheric CO2 concentration will impact long-term plant biomass or the dynamics of soil organic matter (SOM) in arid ecosystems. In this study, we investigated the change in the molecular composition of SOM by high resolution mass spectrometry after 10 years exposure to elevated atmospheric CO2 concentrations at the Nevada Desert FACE Facility. Samples were collected from soil profiles from 0 to 1m in 0.2m increments under the dominant evergreen shrub (Larrea tridentata). The differences in the composition of SOM were more evident in soils close to the surface and consistent with higher bulk soil organic carbon (C) and total nitrogen (N) concentrations under elevated than ambient CO2, reflecting increased net productivity of shrubs under elevated CO2, which could be attributed to increased litter input from above-ground biomass and/or shallow roots, root exudation and/or microbial residues. This was further supported by the significant increase in the abundance of amino sugars-, protein- and carbohydrate-like compounds. These compounds are involved in diverse pathways ranging from sugars and amino-acid metabolism to lipid biosynthesis. This indicates increased activity and metabolism under elevated CO2 and suggests that elevated CO2 have altered microbial C use patterns, reflecting changes in the quality and quantity of soil C inputs. A significant increase in the mineral-bound soil organic C was also observed in the surface soils under elevated CO2. This was accompanied by increased microbial residues as identified by mass spectrometry that supports microbial lipid analysis, and reflecting accelerated microbial turnover under elevated CO2. Fungal neutral lipid fatty acids (NLFA) abundance doubled under elevated CO2. When provided with excess labile compounds, such as root exudates, and with limited supply of nutrients, fungi assimilate the excess labile C and store it as NLFA likely contributing to increased total N

  1. Topobathymetric elevation model development using a new methodology: Coastal National Elevation Database

    Science.gov (United States)

    Danielson, Jeffrey J.; Poppenga, Sandra K.; Brock, John C.; Evans, Gayla A.; Tyler, Dean; Gesch, Dean B.; Thatcher, Cindy A.; Barras, John

    2016-01-01

    During the coming decades, coastlines will respond to widely predicted sea-level rise, storm surge, and coastalinundation flooding from disastrous events. Because physical processes in coastal environments are controlled by the geomorphology of over-the-land topography and underwater bathymetry, many applications of geospatial data in coastal environments require detailed knowledge of the near-shore topography and bathymetry. In this paper, an updated methodology used by the U.S. Geological Survey Coastal National Elevation Database (CoNED) Applications Project is presented for developing coastal topobathymetric elevation models (TBDEMs) from multiple topographic data sources with adjacent intertidal topobathymetric and offshore bathymetric sources to generate seamlessly integrated TBDEMs. This repeatable, updatable, and logically consistent methodology assimilates topographic data (land elevation) and bathymetry (water depth) into a seamless coastal elevation model. Within the overarching framework, vertical datum transformations are standardized in a workflow that interweaves spatially consistent interpolation (gridding) techniques with a land/water boundary mask delineation approach. Output gridded raster TBDEMs are stacked into a file storage system of mosaic datasets within an Esri ArcGIS geodatabase for efficient updating while maintaining current and updated spatially referenced metadata. Topobathymetric data provide a required seamless elevation product for several science application studies, such as shoreline delineation, coastal inundation mapping, sediment-transport, sea-level rise, storm surge models, and tsunami impact assessment. These detailed coastal elevation data are critical to depict regions prone to climate change impacts and are essential to planners and managers responsible for mitigating the associated risks and costs to both human communities and ecosystems. The CoNED methodology approach has been used to construct integrated TBDEM models

  2. Severe bleeding after sinus floor elevation using the transcrestal technique

    DEFF Research Database (Denmark)

    Jensen, Simon Storgard; Eriksen, Jacob; Schiodt, Morten

    2012-01-01

    To present a rare but clinically significant complication to sinus floor elevation (SFE) using the transcrestal technique.......To present a rare but clinically significant complication to sinus floor elevation (SFE) using the transcrestal technique....

  3. Elevated carbon dioxide: impacts on soil and plant water relations

    National Research Council Canada - National Science Library

    Kirkham, M. B

    2011-01-01

    .... Focusing on this critical issue, Elevated Carbon Dioxide: Impacts on Soil and Plant Water Relations presents research conducted on field-grown sorghum, winter wheat, and rangeland plants under elevated CO2...

  4. Digital Elevation Models (DEMs) for the main 8 Hawaiian Islands

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Digital elevation model (DEM) data are arrays of regularly spaced elevation values referenced horizontally either to a Universal Transverse Mercator (UTM) projection...

  5. Elevated rheumatoid factor and long term risk of rheumatoid arthritis

    DEFF Research Database (Denmark)

    Nielsen, Sune F; Bojesen, Stig E; Schnohr, Peter

    2012-01-01

    To test whether elevated concentration of rheumatoid factor is associated with long term development of rheumatoid arthritis.......To test whether elevated concentration of rheumatoid factor is associated with long term development of rheumatoid arthritis....

  6. Greenland 5 km DEM, Ice Thickness, and Bedrock Elevation Grids

    Data.gov (United States)

    National Aeronautics and Space Administration — A Digital Elevation Model (DEM), ice thickness grid, and bedrock elevation grid of Greenland acquired as part of the PARCA program are available in ASCII text format...

  7. A NEW HIGH-RESOLUTION ELEVATION MODEL OF GREENLAND DERIVED FROM TANDEM-X

    Directory of Open Access Journals (Sweden)

    B. Wessel

    2016-06-01

    Full Text Available In this paper we present for the first time the new digital elevation model (DEM for Greenland produced by the TanDEM-X (TerraSAR add-on for digital elevation measurement mission. The new, full coverage DEM of Greenland has a resolution of 0.4 arc seconds corresponding to 12 m. It is composed of more than 7.000 interferometric synthetic aperture radar (InSAR DEM scenes. X-Band SAR penetrates the snow and ice pack by several meters depending on the structures within the snow, the acquisition parameters, and the dielectricity constant of the medium. Hence, the resulting SAR measurements do not represent the surface but the elevation of the mean phase center of the backscattered signal. Special adaptations on the nominal TanDEM-X DEM generation are conducted to maintain these characteristics and not to raise or even deform the DEM to surface reference data. For the block adjustment, only on the outer coastal regions ICESat (Ice, Cloud, and land Elevation Satellite elevations as ground control points (GCPs are used where mostly rock and surface scattering predominates. Comparisons with ICESat data and snow facies are performed. In the inner ice and snow pack, the final X-Band InSAR DEM of Greenland lies up to 10 m below the ICESat measurements. At the outer coastal regions it corresponds well with the GCPs. The resulting DEM is outstanding due to its resolution, accuracy and full coverage. It provides a high resolution dataset as basis for research on climate change in the arctic.

  8. Does growth under elevated CO{sub 2} moderate photoacclimation in rice?

    Energy Technology Data Exchange (ETDEWEB)

    Hubbart, S.; Murchie, E.H.; Lake, J.A. [Univ. of Nottingham. School of Bioscience, Sutton Bonington (United Kingdom); Bird, S. [Univ. of York. Centre for Novel Agricultural Products, Dept. of Biology, York (United Kingdom)

    2013-06-01

    Acclimation of plant photosynthesis to light irradiance (photoacclimation) involves adjustments in levels of pigments and proteins and larger scale changes in leaf morphology. To investigate the impact of rising atmospheric CO{sub 2} on crop physiology, we hypothesize that elevated CO{sub 2} interacts with photoacclimation in rice (Oryza sativa). Rice was grown under high light (HL: 700 {mu}mol m{sup -2} s{sup -1}), low light (LL: 200 {mu}mol m{sup -2} s{sup -1}), ambient CO{sub 2} (400 {mu}l l{sup -1}) and elevated CO{sub 2} (1000 {mu}l l{sup -1}). Leaf six was measured throughout. Obscuring meristem tissue during development did not alter leaf thickness indicating that mature leaves are responsible for sensing light during photoacclimation. Elevated CO{sub 2} raised growth chamber photosynthesis and increased tiller formation at both light levels, while it increased leaf length under LL but not under HL. Elevated CO{sub 2} always resulted in increased leaf growth rate and tiller production. Changes in leaf thickness, leaf area, Rubisco content, stem and leaf starch, sucrose and fructose content were all dominated by irradiance and unaffected by CO{sub 2}. However, stomata responded differently; they were significantly smaller in LL grown plants compared to HL but this effect was significantly suppressed under elevated CO{sub 2}. Stomatal density was lower under LL, but this required elevated CO{sub 2} and the magnitude was adaxial or abaxial surface-dependent. We conclude that photoacclimation in rice involves a systemic signal. Furthermore, extra carbohydrate produced under elevated CO{sub 2} is utilized in enhancing leaf and tiller growth and does not enhance or inhibit any feature of photoacclimation with the exception of stomatal morphology. (Author)

  9. PREPARATION OF THE DIGITAL ELEVATION MODEL FOR ORTHOPHOTO CR PRODUCTION

    Directory of Open Access Journals (Sweden)

    Z. Švec

    2016-06-01

    Full Text Available The Orthophoto CR is produced in co-operation with the Land Survey Office and the Military Geographical and Hydrometeorological Office. The product serves to ensure a defence of the state, integrated crisis management, civilian tasks in support of the state administration and the local self-government of the Czech Republic as well. It covers the whole area of the Republic and for ensuring its up-to-datedness is reproduced in the biennial period. As the project is countrywide, it keeps the project within the same parameters in urban and rural areas as well. Due to economic reasons it can´t be produced as a true ortophoto because it requires large side and forward overlaps of the aerial photographs and a preparation of the digital surface model instead of the digital terrain model. Use of DTM without some objects of DSM for orthogonalization purposes cause undesirable image deformations in the Orthophoto. There are a few data sets available for forming a suitable elevation model. The principal source should represent DTMs made from data acquired by the airborne laser scanning of the entire area of the Czech Republic that was carried out in the years 2009-2013, the DMR4G in the grid form and the DMR5G in TIN form respectively. It can be replenished by some vector objects (bridges, dams, etc. taken from the geographic base data of the Czech Republic or obtained by new stereo plotting. It has to be taken into account that the option of applying DSM made from image correlation is also available. The article focuses on the possibilities of DTM supplement for ortogonalization. It looks back to the recent transition from grid to hybrid elevation models, problems that occurred, its solution and getting some practical remarks. Afterwards it assesses the current state and deals with the options for updating the model. Some accuracy analysis are included.

  10. 46 CFR 116.438 - Stairtowers, stairways, ladders, and elevators.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Stairtowers, stairways, ladders, and elevators. 116.438... AND ARRANGEMENT Fire Protection § 116.438 Stairtowers, stairways, ladders, and elevators. (a) A vessel... the requirements for stairways, ladders, and elevators in § 72.05-20 of this chapter. (b) Materials...

  11. 7 CFR 800.25 - Required elevator and merchandising records.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 7 2010-01-01 2010-01-01 false Required elevator and merchandising records. 800.25... REGULATIONS Recordkeeping and Access to Facilities § 800.25 Required elevator and merchandising records. (a) Elevator and merchandiser recordkeeping. Every person and every State or political subdivision of a State...

  12. 30 CFR 77.1400 - Personnel hoists and elevators.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Personnel hoists and elevators. 77.1400 Section... MINES Personnel Hoisting § 77.1400 Personnel hoists and elevators. Except as provided in § 77.1430, the sections in this Subpart O apply only to hoists and elevators, together with their appurtenances, that are...

  13. 29 CFR 1918.87 - Ship's cargo elevators.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Ship's cargo elevators. 1918.87 Section 1918.87 Labor... (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR LONGSHORING Handling Cargo § 1918.87 Ship's cargo elevators. (a) Safe working load. The safe working loads of ship's cargo elevators shall be determined and followed...

  14. 46 CFR 72.05-20 - Stairways, ladders, and elevators.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 3 2010-10-01 2010-10-01 false Stairways, ladders, and elevators. 72.05-20 Section 72... CONSTRUCTION AND ARRANGEMENT Structural Fire Protection § 72.05-20 Stairways, ladders, and elevators. (a)(1..., ladders, and elevators within main machinery spaces or cargo holds are not covered by the general...

  15. 14 CFR 23.155 - Elevator control force in maneuvers.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Elevator control force in maneuvers. 23.155 Section 23.155 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... Controllability and Maneuverability § 23.155 Elevator control force in maneuvers. (a) The elevator control force...

  16. Microbes do not follow the elevational diversity patterns of plants and animals.

    Science.gov (United States)

    Fierer, Noah; McCain, Christy M; Meir, Patrick; Zimmermann, Michael; Rapp, Joshua M; Silman, Miles R; Knight, Rob

    2011-04-01

    The elevational gradient in plant and animal diversity is one of the most widely documented patterns in ecology and, although no consensus explanation exists, many hypotheses have been proposed over the past century to explain these patterns. Historically, research on elevational diversity gradients has focused almost exclusively on plant and animal taxa. As a result, we do not know whether microbes exhibit elevational gradients in diversity that parallel those observed for macroscopic taxa. This represents a key knowledge gap in ecology, especially given the ubiquity, abundance, and functional importance of microbes. Here we show that, across a montane elevational gradient in eastern Peru, bacteria living in three distinct habitats (organic soil, mineral soil, and leaf surfaces) exhibit no significant elevational gradient in diversity (r20.1 in all cases), in direct contrast to the significant diversity changes observed for plant and animal taxa across the same montane gradient (r2>0.75, P<0.001 in all cases). This finding suggests that the biogeographical patterns exhibited by bacteria are fundamentally different from those of plants and animals, highlighting the need for the development of more inclusive concepts and theories in biogeography to explain these disparities.

  17. A new multiple spatial resolution estimate of the bedrock elevation of the Greenland ice sheet.

    Science.gov (United States)

    Griggs, Jennifer; Bamber, Jonathan; Plummer, Joel; Gogineni, Sivaprasad; Rignot, Eric

    2010-05-01

    Gridded bedrock elevation for the Greenland ice sheet has previously been determined with 5 km postings. The true resolution of the data set was, in places, however, considerably coarser than this due to the across-track spacing of flight lines. Errors were estimated to be on the order of a few percent in the centre of the ice sheet but increasing markedly in relative magnitude near the margins, where, for numerical modelling, accurate thickness is particularly critical. We use new airborne and satellite estimates of ice thickness and surface elevation to determine the bed topography for the whole of Greenland. In particular, the University of Kansas have in recent years, flown an airborne ice-penetrating radar system with close flightline spacing over several key outlet glacier systems. This allows us to produce a multi-resolution bedrock elevation dataset with the high spatial resolution needed for ice dynamic modelling over these key outlet glaciers and coarser resolution over the more sparsely sampled interior. Airborne ice thickness and elevation from CReSIS obtained between 1993 and 2009 are combined with JPL, DONNEES data covering the marginal areas along the south west coast from 2009. Data collected in the 1970's by the Technical University of Denmark were also used in interior areas with sparse coverage from other sources. Marginal elevation data from the ICESat laser altimeter were used to help constrain the ice thickness and bed topography close to the ice sheet margin where, typically, the terrestrial observations have poor sampling between flight tracks.

  18. Elevational Dependence of Catchment-scale Evapotranspiration Partitioning as Revealed by Water Stable Isotopes

    Science.gov (United States)

    Yamanaka, T.; Sato, R.

    2017-12-01

    Transpiration (T) through plants (i.e., green water) does not induce isotopic fractionation, although evaporation (E) from soils and water surfaces do. Therefore, water stable isotopes offer a powerful tool to partition evapotranspiration (ET) components. We attempted to evaluate catchment-scale T/ET for five mountainous catchments in the central Japan, using river water isotopes and isotope maps of precipitation and soil water as well as climatic and radar precipitation maps. The estimated T/ET ranged from 56% to 79% (ET not including interception loss), and negatively correlated with mean elevation of the catchments (r = -0.88). This is due to decreasing transpiration (-82 mm/yr per 100 m) and slightly increasing evaporation (8 mm/yr per 100 m) with increasing elevation. Another estimation scheme using isotope data only showed a positive correlation between elevation and E/P*, where P* is effective precipitation defined by gross precipitation minus interception. Because the forest coverage within the catchments has positive correlation with catchment-mean-elevation, both decrease in transpiration and increase in soil evaporation seem to reflect structural change in forests (e.g., dense to sparse) along elevation and thus temperature gradients. Applying the space-for-time substitution, our results indicates that global warming will increase transpiration (and thus carbon intake) at mid-latitude mountainous landscapes.

  19. Rangeland -- Plant responses to elevated CO{sub 2}. Progress report

    Energy Technology Data Exchange (ETDEWEB)

    Owensby, C.E.; Coyne, P.I.; Ham, J.M.; Parton, W.; Rice, C.; Auen, L.M.; Adam, N.

    1992-10-01

    Several broad conclusions which can be drawn from the work that was accomplished during the first 3-year phase of the study is described. In prairie ecosystems dominated by C{sub 4} grasses, it is likely that elevated atmospheric CO{sub 2} will increase ecosystem level productivity, with a greater increase in belowground productivity. The increased productivity will primarily result from increased water use efficiency due to the anti-transpirant action of CO{sub 2}. Fumigation chambers are directly confounded with elevated CO{sub 2} effects, in that both reduce evapotranspiration. The reduced evapotranspiration of the fumigation chamber is primarily through reduced wind speeds and reduced radiation. In very dry years, fumigation chamber effects are negligible, but in years with normal precipitation, chamber effects and elevated CO{sub 2} effects are essentially equal with respect to reduced evapotranspiration effects. Increased production under elevated CO{sub 2} results in reduced nitrogen concentration in the herbage and increased fiber concentrations. Consequently, digestibility of the herbage is reduced, and microbial degradation of surface litter and soil organic matter is slowed. On the negative side, ruminant productivity will likely be reduced substantially, but increased carbon storage in the soil may buffer against future rise in atmospheric CO{sub 2}. Tallgrass prairie will not likely change greatly in botanical composition, since the C{sub 4} dominants responded to elevated CO{sub 2} more than the C{sub 3} subdominants.

  20. Study of influence of climber motion on the space elevator dynamics

    Directory of Open Access Journals (Sweden)

    A. S. Ledkov

    2014-01-01

    Full Text Available The operation of launching a payload into orbit by means of a space elevator is considered in this paper. The space elevator is a mechanical system that consists of a tether, a space station, and a climber. The tether connects the surface of the Earth with the space station, which is above the geostationary orbit. The climber lifts the payload to the required altitude. Then it is disconnected from the space elevator and starts free orbital flight. Creation of the space elevator will significantly reduce the cost of payloads delivery to orbit.The objective of this work is to study dynamics of the space elevator taking into account the climber motion. A mathematical model, which takes into consideration bending of the tether and features of the climber construction, is developed. In contrast to existing models, the climber is considered not as a mass point, but as a mechanical system consisting of two homogeneous weighty cylinders connected by a weightless strap upon which the payload is located. The payload and the space stations are considered as mass points. The tether is simulated as a pair of inelastic inextensible bars with variable length. The area of bars cross-sections is defined by a function, which depends on the distance to the end of the bars. Motion occurs in the equatorial plane in the gravitational field of the Earth.It is shown that lifting of the climber leads to swinging of the space elevator in the equatorial plane. This effect is caused by the influence of Coriolis forces of inertia. After stopping of the climber the space elevator oscillates about the vertical. An effect of the payload mass on amplitude of the space elevator oscillation is studied. It is shown that the increasing payload mass leads to the growing amplitude of the space elevator oscillations. A control torque providing steady lifting of the payload is obtained. The results of the calculations show that the practical implementation of the space elevator

  1. Variability of soil moisture and its relationship with surface albedo ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Earth System Science; Volume 119; Issue 4. Variability of soil moisture and its relationship with surface albedo and soil thermal ... The diurnal variation of surface albedo appears as a U-shaped curve on sunny days. Surface albedo decreases with the increase of solar elevation angle, and it tends ...

  2. Elevated temperature forming method and preheater apparatus

    Science.gov (United States)

    Krajewski, Paul E; Hammar, Richard Harry; Singh, Jugraj; Cedar, Dennis; Friedman, Peter A; Luo, Yingbing

    2013-06-11

    An elevated temperature forming system in which a sheet metal workpiece is provided in a first stage position of a multi-stage pre-heater, is heated to a first stage temperature lower than a desired pre-heat temperature, is moved to a final stage position where it is heated to a desired final stage temperature, is transferred to a forming press, and is formed by the forming press. The preheater includes upper and lower platens that transfer heat into workpieces disposed between the platens. A shim spaces the upper platen from the lower platen by a distance greater than a thickness of the workpieces to be heated by the platens and less than a distance at which the upper platen would require an undesirably high input of energy to effectively heat the workpiece without being pressed into contact with the workpiece.

  3. Elevated temperature fatigue testing of metals

    Science.gov (United States)

    Hirschberg, M. H.

    1981-01-01

    The major technology areas needed to perform a life prediction of an aircraft turbine engine hot section component are discussed and the steps required for life prediction are outlined. These include the determination of the operating environment, the calculation of the thermal and mechanical loading of the component, the cyclic stress-strain and creep behavior of the material required for structural analysis, and the structural analysis to determine the local stress-strain-temperature-time response of the material at the critical location in the components. From a knowledge of the fatigue, creep, and failure resistance of the material, a prediction of the life of the component is made. Material characterization and evaluation conducted for the purpose of calculating fatigue crack initiation lives of components operating at elevated temperatures are emphasized.

  4. Effects of lixisenatide on elevated liver transaminases

    DEFF Research Database (Denmark)

    Gluud, Lise L; Knop, Filip K; Vilsbøll, Tina

    2014-01-01

    identified on AST, alkaline phosphatase or bilirubin. No evidence of bias was identified. Mixed effect multilevel meta-regression analyses suggest that the benefit of lixisenatide on ALT was limited to patients who were overweight or obese. CONCLUSIONS: This review suggests that lixisenatide increases......) on lixisenatide versus placebo or active comparators for type 2 diabetes were included. PARTICIPANTS: Individual patient data were retrieved to calculate outcomes for patients with elevated liver blood tests. MAIN OUTCOME MEASURES: Normalisation of alanine aminotransferase (ALT) and aspartate aminotransferase...... (AST). DATA SYNTHESIS: The results of included trials were combined in meta-analyses. Sequential, subgroup and regression analyses were performed to evaluate heterogeneity and bias. RESULTS: We included 12 RCTs on lixisenatide versus placebo and 3 RCTs with the active comparators liraglutide, exenatide...

  5. Magnesium sacrificial anode behavior at elevated temperature

    International Nuclear Information System (INIS)

    Othman, Mohsen Othman

    2006-01-01

    Magnesium sacrificial anode coupled to mild steel was tasted in sodium chloride and tap water environments at elevated temperatures. The anode failed to protect the mild steel specimens in tap water environment at all temperatures specified. This was partly due to low conductivity of this medium. The temperature factor did not help to activate the anode in this medium. In sodium chloride environment the anode demonstrated good protection for steel cathodes. The weight loss was high for magnesium in sodium chloride environment particularly beyond 60 degree centigrade. In tap water environment the weight loss was negligible for the anode. It also suffered localized shallow pitting corrosion. Magnesium anode cannot be utilized where high temperature is involved particularly in high conductivity mediums. Protection of structures containing high resistivity waters is not feasible using sacrificial anode system. (author)

  6. Superhydrophobic surfaces

    Science.gov (United States)

    Wang, Evelyn N; McCarthy, Matthew; Enright, Ryan; Culver, James N; Gerasopoulos, Konstantinos; Ghodssi, Reza

    2015-03-24

    Surfaces having a hierarchical structure--having features of both microscale and nanoscale dimensions--can exhibit superhydrophobic properties and advantageous condensation and heat transfer properties. The hierarchical surfaces can be fabricated using biological nanostructures, such as viruses as a self-assembled nanoscale template.

  7. Spherical Surfaces

    DEFF Research Database (Denmark)

    Brander, David

    2016-01-01

    We study surfaces of constant positive Gauss curvature in Euclidean 3-space via the harmonicity of the Gauss map. Using the loop group representation, we solve the regular and the singular geometric Cauchy problems for these surfaces, and use these solutions to compute several new examples. We give...

  8. Unusual head and neck injury in elevator: autopsy study.

    Science.gov (United States)

    Eren, B; Türkmen, N; Dokgöz, H

    2012-10-01

    Industrial injuries related to auto-load-carrying vehicles were not frequently reported in the literature. Presented case was, 31-year-old male furniture worker. Deceased was found in awkward position in furniture workshop. Victim was observed on his knees in front of the elevator, head and neck lodged within openings of the elevator, and head and neck structures compressed-guillotined by the lower platform of the elevator were detected. We presented rare case of head and neck compression by elevator. Key words: head - neck - accidents - elevator - autopsy.

  9. Elevated carbon dioxide alters the plasma composition and behaviour of a shark

    OpenAIRE

    Green, Leon; Jutfelt, Fredrik

    2014-01-01

    Increased carbon emissions from fossil fuels are increasing the pCO2 of the ocean surface waters in a process called ocean acidification. Elevated water pCO2 can induce physiological and behavioural effects in teleost fishes, although there appear to be large differences in sensitivity between species. There is currently no information available on the possible responses to future ocean acidification in elasmobranch fishes. We exposed small-spotted catsharks (Scyliorhinus canicula) to either ...

  10. Traction sheave elevator, hoisting unit and machine space

    Science.gov (United States)

    Hakala, Harri; Mustalahti, Jorma; Aulanko, Esko

    2000-01-01

    Traction sheave elevator consisting of an elevator car moving along elevator guide rails, a counterweight moving along counterweight guide rails, a set of hoisting ropes (3) on which the elevator car and counterweight are suspended, and a drive machine unit (6) driving a traction sheave (7) acting on the hoisting ropes (3) and placed in the elevator shaft. The drive machine unit (6) is of a flat construction. A wall of the elevator shaft is provided with a machine space with its open side facing towards the shaft, the essential parts of the drive machine unit (6) being placed in the space. The hoisting unit (9) of the traction sheave elevator consists of a substantially discoidal drive machine unit (6) and an instrument panel (8) mounted on the frame (20) of the hoisting unit.

  11. Purwarupa Sistem Kontrol Elevator Berbasis Programable Logic Control

    Directory of Open Access Journals (Sweden)

    Fathahillah Fathahillah

    2017-12-01

    Full Text Available Various methods / types of controls developed in accordance with industry needs one of them in the field of building automation system. One of the controls in the field of building automation system is the elevator control system (elevator. Early elevator control systems that transport humans or goods as vertical transportation vehicles are still conventional using human power, then evolved using steam engines, until now the elevators use AC motors equipped with control systems. The purpose of this research is to design the prototype of elevator control system using programmable logic control (PLC. The type of PLC controller used in the study using Omron PLC. The results show the design of prototype of elevator control system using PLC successfully and can control eleveator in accordance with its function, besides its programming form can be more simple.

  12. Space Elevators: Building a Permanent Bridge for Space Exploration and Economic Development

    Science.gov (United States)

    Smitherman, David V., Jr.; Howell, Joe T. (Technical Monitor)

    2000-01-01

    A space elevator is a physical connection from the surface of the Earth to a geo-stationary orbit above the Earth approximately 35,786 km in altitude. Its center of mass is at the geo-stationary point such that it has a 24-hour orbit, and stays over the same point above the equator as the Earth rotates on its axis. The structure is utilized as a transportation and utility system for moving payloads, power, and gases between the surface of the Earth and space. It makes the physical connection from Earth to space in the same way a bridge connects two cities across a body of' water. The space elevator may be an important concept for the future development of space in the latter part of the 21th century. It has the potential to provide mass-transportation to space in the same way highways, railroads, power lines, and pipelines provide mass-transportation across the Earth's surface. The low energy requirements for moving payloads up and down the elevator make it one of only a few concepts that has the potential of lowering the cost to orbit to less than $10 per kilogram. This paper will summarize the findings from a 1999 NASA workshop on Space Elevators held at the NASA Marshall Space Flight Center (MSFC). The workshop was sponsored by the Advanced Projects Office in the Flight Projects Directorate at MSFC, and was organized in cooperation with the Advanced Space Transportation Program at MSFC and the Advanced Concepts Office in the Office of Space Flight at NASA Headquarters. New concepts will be examined for space elevator construction and a number of issues will be discussed that has helped to bring the space elevator concept out of the realm of science fiction and into the realm of possibility. In conclusion, it appears that the space elevator concept may well he possible in the latter part of the 21st century if proper planning and technology development is emphasized to resolve key issues in the development of this advanced space infrastructure concept.

  13. Elevated pCO2 enhances bacterioplankton removal of organic carbon.

    Science.gov (United States)

    James, Anna K; Passow, Uta; Brzezinski, Mark A; Parsons, Rachel J; Trapani, Jennifer N; Carlson, Craig A

    2017-01-01

    Factors that affect the removal of organic carbon by heterotrophic bacterioplankton can impact the rate and magnitude of organic carbon loss in the ocean through the conversion of a portion of consumed organic carbon to CO2. Through enhanced rates of consumption, surface bacterioplankton communities can also reduce the amount of dissolved organic carbon (DOC) available for export from the surface ocean. The present study investigated the direct effects of elevated pCO2 on bacterioplankton removal of several forms of DOC ranging from glucose to complex phytoplankton exudate and lysate, and naturally occurring DOC. Elevated pCO2 (1000-1500 ppm) enhanced both the rate and magnitude of organic carbon removal by bacterioplankton communities compared to low (pre-industrial and ambient) pCO2 (250 -~400 ppm). The increased removal was largely due to enhanced respiration, rather than enhanced production of bacterioplankton biomass. The results suggest that elevated pCO2 can increase DOC consumption and decrease bacterioplankton growth efficiency, ultimately decreasing the amount of DOC available for vertical export and increasing the production of CO2 in the surface ocean.

  14. Note: A method for minimizing oxide formation during elevated temperature nanoindentation

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, I. C.; Hodge, A. M., E-mail: ahodge@usc.edu [Department of Aerospace and Mechanical Engineering, University of Southern California, 3650 McClintock Avenue OHE430, Los Angeles, California 90089 (United States); Garcia-Sanchez, E. [Department of Aerospace and Mechanical Engineering, University of Southern California, 3650 McClintock Avenue OHE430, Los Angeles, California 90089 (United States); Facultad de Ingeniería Mecánica y Eléctrica, Universidad Autónoma de Nuevo León, Av. Universidad S/N, San Nicolás de los Garza, NL 66450 (Mexico)

    2014-09-15

    A standardized method to protect metallic samples and minimize oxide formation during elevated-temperature nanoindentation was adapted to a commercial instrument. Nanoindentation was performed on Al (100), Cu (100), and W (100) single crystals submerged in vacuum oil at 200 °C, while the surface morphology and oxidation was carefully monitored using atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). The results were compared to room temperature and 200 °C nanoindentation tests performed without oil, in order to evaluate the feasibility of using the oil as a protective medium. Extensive surface characterization demonstrated that this methodology is effective for nanoscale testing.

  15. WIND TUNNEL EVALUATION FOR CONTROL TRANSITION FROM ELEVATOR TO STABILATOR OF SMALL UAV

    Directory of Open Access Journals (Sweden)

    ZULHILMY SAHWEE

    2017-06-01

    Full Text Available Faulty control surface actuator in a small Unmanned Aerial Vehicles (sUAV could be overcome with a few techniques. Redundant actuators, analytical redundancy or combination of both are normally used as fault accommodation techniques. In this paper, the accommodation technique of faulty elevator actuator is presented. This technique uses a standby control surface as temporary control reallocation. Wind tunnel measurement facility is set up for the experimental validation and it is compared with FoilSim software. Flat plate airfoil which was used as horizontal stabilizer, is simulated using numerical model and it is validated using the wind tunnel test. Then, a flat airfoil is designed to be used as stabilator for the recovery of faulty elevator actuator. Results show the different deflection angle is needed when transferring from one control surface to another. From the analysis, the proposed method could be implemented without affecting the pitch stability during control surface transition. The alternate control surface accommodation technique proves to be promising for higher reliability sUAV in the case of a faulty on-board actuator.

  16. Elevated carbon dioxide and ozone alter productivity and ecosystem carbon content in northern temperate forests

    Science.gov (United States)

    Talhelm, Alan F; Pregitzer, Kurt S; Kubiske, Mark E; Zak, Donald R; Campany, Courtney E; Burton, Andrew J; Dickson, Richard E; Hendrey, George R; Isebrands, J G; Lewin, Keith F; Nagy, John; Karnosky, David F

    2014-01-01

    Three young northern temperate forest communities in the north-central United States were exposed to factorial combinations of elevated carbon dioxide (CO2) and tropospheric ozone (O3) for 11 years. Here, we report results from an extensive sampling of plant biomass and soil conducted at the conclusion of the experiment that enabled us to estimate ecosystem carbon (C) content and cumulative net primary productivity (NPP). Elevated CO2 enhanced ecosystem C content by 11%, whereas elevated O3 decreased ecosystem C content by 9%. There was little variation in treatment effects on C content across communities and no meaningful interactions between CO2 and O3. Treatment effects on ecosystem C content resulted primarily from changes in the near-surface mineral soil and tree C, particularly differences in woody tissues. Excluding the mineral soil, cumulative NPP was a strong predictor of ecosystem C content (r2 = 0.96). Elevated CO2 enhanced cumulative NPP by 39%, a consequence of a 28% increase in canopy nitrogen (N) content (g N m−2) and a 28% increase in N productivity (NPP/canopy N). In contrast, elevated O3 lowered NPP by 10% because of a 21% decrease in canopy N, but did not impact N productivity. Consequently, as the marginal impact of canopy N on NPP (ΔNPP/ΔN) decreased through time with further canopy development, the O3 effect on NPP dissipated. Within the mineral soil, there was less C in the top 0.1 m of soil under elevated O3 and less soil C from 0.1 to 0.2 m in depth under elevated CO2. Overall, these results suggest that elevated CO2 may create a sustained increase in NPP, whereas the long-term effect of elevated O3 on NPP will be smaller than expected. However, changes in soil C are not well-understood and limit our ability to predict changes in ecosystem C content. PMID:24604779

  17. Elevated body mass index and fatty liver

    Directory of Open Access Journals (Sweden)

    Marović Dragana

    2008-01-01

    Full Text Available Introduction Obesity and overweight, expressed by elevated Body Mass Index (BMI, result from excessive consumption of fatty food and carbohydrates above the body needs. The fat from the blood, through free fatty acids, is taken directly into the liver. Objective The aim of this study was to examine correlation among the accepted ultrasonography findings of the fatty liver and the normal ultrasonography findings and the elevated average level of BMI and those with normal BMI in examinees in one investigation. All was done aimed at proving that the BMI is one of the direct factors of the increased occurence of fatty liver. METHOD The method of the investigation consisted of anthropometric measuring of height and weight on the basis of which there were established BMI values. Consequently, the examinees were divided in two groups: one with normal BMI (under 24.9 kg/m2 and the other with increased BMI (over 25 kg/m2. Fatty liver was diagnosed when the liver of the examinees was observed by ultrasonography. Thus there were given subgroups of the examinees, one with the findings of fatty liver and the second with a normal finding, without changes. After that, the obtained results were statistically analysed. Results It was found that the average level of BMI in the examinees was by two units higher in the subgroup with ultrasonography findings of fatty liver than the average value of BMI in the subgroup with the normal ultrasonography findings of the liver. The difference was tested by the Student's t-test and a significant difference was found. The difference in frequencies of the appearance of the finding of fatty liver in the subgroups was tested by χ2-test. A statistically significant difference was found in frequencies of the appearance of fatty liver in the subgroup with the increased value of BMI. Conclusion The increased BMI, which is represented by overweight and obesity, is one of the direct risk factors which cause fatty liver, checked by

  18. Multi-temporal AirSWOT elevations on the Willamette river: error characterization and algorithm testing

    Science.gov (United States)

    Tuozzolo, S.; Frasson, R. P. M.; Durand, M. T.

    2017-12-01

    We analyze a multi-temporal dataset of in-situ and airborne water surface measurements from the March 2015 AirSWOT field campaign on the Willamette River in Western Oregon, which included six days of AirSWOT flights over a 75km stretch of the river. We examine systematic errors associated with dark water and layover effects in the AirSWOT dataset, and test the efficacies of different filtering and spatial averaging techniques at reconstructing the water surface profile. Finally, we generate a spatially-averaged time-series of water surface elevation and water surface slope. These AirSWOT-derived reach-averaged values are ingested in a prospective SWOT discharge algorithm to assess its performance on SWOT-like data collected from a borderline SWOT-measurable river (mean width = 90m).

  19. Surface boxplots

    KAUST Repository

    Genton, Marc G.

    2014-01-22

    In this paper, we introduce a surface boxplot as a tool for visualization and exploratory analysis of samples of images. First, we use the notion of volume depth to order the images viewed as surfaces. In particular, we define the median image. We use an exact and fast algorithm for the ranking of the images. This allows us to detect potential outlying images that often contain interesting features not present in most of the images. Second, we build a graphical tool to visualize the surface boxplot and its various characteristics. A graph and histogram of the volume depth values allow us to identify images of interest. The code is available in the supporting information of this paper. We apply our surface boxplot to a sample of brain images and to a sample of climate model outputs.

  20. Convex surfaces

    CERN Document Server

    Busemann, Herbert

    2008-01-01

    This exploration of convex surfaces focuses on extrinsic geometry and applications of the Brunn-Minkowski theory. It also examines intrinsic geometry and the realization of intrinsic metrics. 1958 edition.

  1. Surface decontamination

    International Nuclear Information System (INIS)

    Silva, S. da; Teixeira, M.V.

    1986-06-01

    The general methods of surface decontamination used in laboratory and others nuclear installations areas, as well as the procedures for handling radioactive materials and surfaces of work are presented. Some methods for decontamination of body external parts are mentioned. The medical supervision and assistance are required for internal or external contamination involving or not lesion in persons. From this medical radiation protection decontamination procedures are determined. (M.C.K.) [pt

  2. Surface phonons

    CERN Document Server

    Wette, Frederik

    1991-01-01

    In recent years substantial progress has been made in the detection of surface phonons owing to considerable improvements in inelastic rare gas scattering tech­ niques and electron energy loss spectroscopy. With these methods it has become possible to measure surface vibrations in a wide energy range for all wave vectors in the two-dimensional Brillouin zone and thus to deduce the complete surface phonon dispersion curves. Inelastic atomic beam scattering and electron energy loss spectroscopy have started to play a role in the study of surface phonons similar to the one played by inelastic neutron scattering in the investigation of bulk phonons in the last thirty years. Detailed comparison between experimen­ tal results and theoretical studies of inelastic surface scattering and of surface phonons has now become feasible. It is therefore possible to test and to improve the details of interaction models which have been worked out theoretically in the last few decades. At this point we felt that a concise, co...

  3. Gender difference of alanine aminotransferase elevation may be associated with higher hemoglobin levels among male adolescents.

    Directory of Open Access Journals (Sweden)

    Solomon Chih-Cheng Chen

    Full Text Available BACKGROUND: To explore the gender difference of ALT elevation and its association with high hemoglobin levels. METHODS: A cross-sectional study of 3547 adolescents (2005 females, mean age of 16.5?.3 years who were negative for hepatitis B surface antigen received health checkups in 2006. Body mass index (BMI, levels of hemoglobin, ALT and cholesterol were measured. ALT >42 U/L was defined as elevated ALT. Elevated ALT levels were detected in 112 of the 3547 participants (3.3%, more prevalent in males than in females (5.4% vs. 1.4%, p11 g/dl in females or >13.5 g/dl in males, but the cumulative cases of elevated ALT increased more quickly in males. Proportion of elevated ALT increased as either the BMI or hemoglobin level rise, more apparent in male adolescents. Logistic regression modeling showed odds ratio (95% confidence interval were 24.7 (15.0-40.6 for BMI ≥27 kg/m(2; 5.5 (2.9-10.4 for BMI 24-27 kg/m(2; 2.7 (1.3-5.5 for Q5 (top 20th percentile hemoglobin level; and 2.6 (1.6-4.1 for male gender. Further separately fitting the logistic models for two genders, the significance of Q5 hemoglobin level only appeared in the males. CONCLUSIONS: High hemoglobin level is a significant risk factor of ALT elevation after control hepatitis B, obesity and gender. Males have greater risk of abnormal liver function which may be associated with higher hemoglobin levels.

  4. Caribbean mangroves adjust to rising sea level through biotic controls on change in soil elevation

    Science.gov (United States)

    McKee, K.L.; Cahoon, D.R.; Feller, Ilka C.

    2007-01-01

    Aim The long-term stability of coastal ecosystems such as mangroves and salt marshes depends upon the maintenance of soil elevations within the intertidal habitat as sea level changes. We examined the rates and processes of peat formation by mangroves of the Caribbean Region to better understand biological controls on habitat stability. Location Mangrove-dominated islands on the Caribbean coasts of Belize, Honduras and Panama were selected as study sites. Methods Biological processes controlling mangrove peat formation were manipulated (in Belize) by the addition of nutrients (nitrogen or phosphorus) to Rhizophora mangle (red mangrove), and the effects on the dynamics of soil elevation were determined over a 3-year period using rod surface elevation tables (RSET) and marker horizons. Peat composition and geological accretion rates were determined at all sites using radiocarbon-dated cores. Results The addition of nutrients to mangroves caused significant changes in rates of mangrove root accumulation, which influenced both the rate and direction of change in elevation. Areas with low root input lost elevation and those with high rates gained elevation. These findings were consistent with peat analyses at multiple Caribbean sites showing that deposits (up to 10 m in depth) were composed primarily of mangrove root matter. Comparison of radiocarbon-dated cores at the study sites with a sea-level curve for the western Atlantic indicated a tight coupling between peat building in Caribbean mangroves and sea-level rise over the Holocene. Main conclusions Mangroves common to the Caribbean region have adjusted to changing sea level mainly through subsurface accumulation of refractory mangrove roots. Without root and other organic inputs, submergence of these tidal forests is inevitable due to peat decomposition, physical compaction and eustatic sea-level rise. These findings have relevance for predicting the effects of sea-level rise and biophysical processes on tropical

  5. Case study of elevated layers of high sulfate concentration

    International Nuclear Information System (INIS)

    McNaughton, D.J.; Orgill, M.M.

    1979-01-01

    During studies in August 1976 that were part of the Multi-State Atmospheric Power Production Pollutant Study (MAP3S), Alkezweeny et al., (1977) noted that in the Milwaukee urban plume, layers of relatively high sulfate concentrations occurred at high altitudes with respect to the boundary layer. This paper represents a progress report on studies undertaken to investigate possible causes for a bimodel vertical profile of sulfate concentrations. Data presented by Alkezweeny et al., (1977) serve as a basis for this study. Data from August 23, 1976, and August 24, 1978, indicate concentrations relatively high in sulfate, at 1000 and 6000 ft, respectively, with lower concentrations at lower altitudes. Concentrations of trace metals also indicate no peaks in the vertical concentration profiles above the surface. Initial studies of the high, elevated sulfate concentrations have centered on the August 23 measurements taken over southeast Wisconsin using synoptic data from the national weather service, emissions data from the national emissions data bank system (EPA), air quality data from the national air surveillance network (EPA), and satellite photographs from the EROS Data Center

  6. Assessment of Fluctuating Reservoir Elevations Using Hydraulic Models and Impacts to Larval Pacific Lamprey Rearing Habitat in the Bonneville Pool

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Robert P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Rakowski, Cynthia L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Perkins, William A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Richmond, Marshall C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-02-24

    This report presents the results of a modeling assessment of likely lamprey larval habitat that may be impacted by dewatering of the major tributary delta regions in the Bonneville Pool of the Columbia River. This assessment was conducted by the Pacific Northwest National Laboratory (PNNL) for the U.S. Army Corps of Engineers Portland District (CENWP). The goal of the study was to provide baseline data about how the regions of interest would potentially be impacted at three river flows (10, 50, and 90 percent exceedance flow) for four different forebay elevations at Bonneville Dam. Impacts of unsteady flows at The Dalles Dam and changing forebay elevation at Bonneville Dam for a 2-week period were also assessed. The area of dewatered regions was calculated by importing modeled data outputs into a GIS and then calculating the change in inundated area near tributary deltas for the four Bonneville forebay surface elevations. From the modeled output we determined that the overall change in area is less sensitive to elevations changes during higher river discharges. Changing the forebay elevation at Bonneville and the resulting impact to total dewatered regions was greater at the lowest modeled river flow (97 kcfs) and showed the greatest variation at the White Salmon/Hood River delta regions followed by the Wind, Klickitat and the Little White Salmon rivers. To understand how inundation might change on a daily and hourly basis. Unsteady flow models were run for a 2-week period in 2002 and compared to 2014. The water surface elevation in the upstream pool closely follows that of the Bonneville Dam forebay with rapid changes of 1 to 2-ft possible. The data shows that 2.5-ft variation in water surface elevation occurred during this period in 2002 and a 3.7-ft change occurred in 2014. The duration of these changes were highly variable and generally did not stay constant for more than a 5-hr period.

  7. SALTSTONE DISPOSAL FACILITY: DETERMINATION OF THE PROBABLE MAXIMUM WATER TABLE ELEVATION

    International Nuclear Information System (INIS)

    Hiergesell, R

    2005-01-01

    A coverage depicting the configuration of the probable maximum water table elevation in the vicinity of the Saltstone Disposal Facility (SDF) was developed to support the Saltstone program. This coverage is needed to support the construction of saltstone vaults to assure that they remain above the maximum elevation of the water table during the Performance Assessment (PA) period of compliance. A previous investigation to calculate the historical high water table beneath the SDF (Cook, 1983) was built upon to incorporate new data that has since become available to refine that estimate and develop a coverage that could be extended to the perennial streams adjacent to the SDF. This investigation incorporated the method used in the Cook, 1983 report to develop an estimate of the probable maximum water table for a group of wells that either existed at one time at or near the SDF or which currently exist. Estimates of the probable maximum water table at these wells were used to construct 2D contour lines depicting this surface beneath the SDF and extend them to the nearby hydrologic boundaries at the perennial streams adjacent to the SDF. Although certain measures were implemented to assure that the contour lines depict a surface above which the water table will not rise, the exact elevation of this surface cannot be known with complete certainty. It is therefore recommended that the construction of saltstone vaults incorporate a vertical buffer of at least 5-feet between the base of the vaults and the depicted probable maximum water table elevation. This should provide assurance that the water table under the wet extreme climatic condition will never rise to intercept the base of a vault

  8. Application of Semi-Automated Filter to Improve Waveform Lidar Sub-Canopy Elevation Model

    Directory of Open Access Journals (Sweden)

    Yongwei Sheng

    2012-05-01

    Full Text Available Modeling sub-canopy elevation is an important step in the processing of waveform lidar data to measure three dimensional forest structure. Here, we present a methodology based on high resolution discrete-return lidar (DRL to correct the ground elevation derived from large-footprint Laser Vegetation Imaging Sensor (LVIS and to improve measurement of forest structure. We use data acquired over Barro Colorado Island, Panama by LVIS large-footprint lidar (LFL in 1998 and DRL in 2009. The study found an average vertical difference of 28.7 cm between 98,040 LVIS last-return points and the discrete-return lidar ground surface across the island. The majority (82.3% of all LVIS points matched discrete return elevations to 2 m or less. Using a multi-step process, the LVIS last-return data is filtered using an iterative approach, expanding window filter to identify outlier points which are not part of the ground surface, as well as applying vertical corrections based on terrain slope within the individual LVIS footprints. The results of the experiment demonstrate that LFL ground surfaces can be effectively filtered using methods adapted from discrete-return lidar point filtering, reducing the average vertical error by 15 cm and reducing the variance in LVIS last-return data by 70 cm. The filters also reduced the largest vertical estimations caused by sensor saturation in the upper reaches of the forest canopy by 14.35 m, which improve forest canopy structure measurement by increasing accuracy in the sub-canopy digital elevation model.

  9. Clutch size declines with elevation in tropical birds

    Science.gov (United States)

    Boyce, A.J.; Freeman, Benjamin G.; Mitchell, Adam E.; Martin, Thomas E.

    2015-01-01

    Clutch size commonly decreases with increasing elevation among temperate-zone and subtropical songbird species. Tropical songbirds typically lay small clutches, thus the ability to evolve even smaller clutch sizes at higher elevations is unclear and untested. We conducted a comparative phylogenetic analysis using data gathered from the literature to test whether clutch size varied with elevation among forest passerines from three tropical biogeographic regions—the Venezuelan Andes and adjacent lowlands, Malaysian Borneo, and New Guinea. We found a significant negative effect of elevation on variation in clutch size among species. We found the same pattern using field data sampled across elevational gradients in Venezuela and Malaysian Borneo. Field data were not available for New Guinea. Both sets of results demonstrate that tropical montane species across disparate biogeographic realms lay smaller clutches than closely related low-elevation species. The environmental sources of selection underlying this pattern remain uncertain and merit further investigation.

  10. Estimation of Mass Balance of the Grosser Aletschgletscher, Swiss Alps, from ICESat Laser Altimetry Data and Digital Elevation Models

    Directory of Open Access Journals (Sweden)

    Jan Kropáček

    2014-06-01

    Full Text Available Traditional glaciological mass balance measurements of mountain glaciers are a demanding and cost intensive task. In this study, we combine data from the Ice Cloud and Elevation Satellite (ICESat acquired between 2003 and 2009 with air and space borne Digital Elevation Models (DEMs in order to derive surface elevation changes of the Grosser Aletschgletscher in the Swiss Alps. Three different areas of the glacier are covered by one nominal ICESat track, allowing us to investigate the performance of the approach under different conditions in terms of ICESat data coverage, and surface characteristics. In order to test the sensitivity of the derived trend in surface lowering, several variables were tested. Employing correction for perennial snow accumulation, footprint selection and adequate reference DEM, we estimated a mean mass balance of −0.92 ± 0.18 m w.e. a−1. for the whole glacier in the studied time period. The resulting mass balance was validated by a comparison with another geodetic approach based on the subtraction of two DEMs for the years 1999 and 2009. It appears that the processing parameters need to be selected depending on the amount of available ICESat measurements, quality of the elevation reference and character of the glacier surface.

  11. Patterns of care and persistence after incident elevated blood pressure.

    Science.gov (United States)

    Daley, Matthew F; Sinaiko, Alan R; Reifler, Liza M; Tavel, Heather M; Glanz, Jason M; Margolis, Karen L; Parker, Emily; Trower, Nicole K; Chandra, Malini; Sherwood, Nancy E; Adams, Kenneth; Kharbanda, Elyse O; Greenspan, Louise C; Lo, Joan C; O'Connor, Patrick J; Magid, David J

    2013-08-01

    Screening for hypertension in children occurs during routine care. When blood pressure (BP) is elevated in the hypertensive range, a repeat measurement within 1 to 2 weeks is recommended. The objective was to assess patterns of care after an incident elevated BP, including timing of repeat BP measurement and likelihood of persistently elevated BP. This retrospective study was conducted in 3 health care organizations. All children aged 3 through 17 years with an incident elevated BP at an outpatient visit during 2007 through 2010 were identified. Within this group, we assessed the proportion who had a repeat BP measured within 1 month of their incident elevated BP and the proportion who subsequently met the definition of hypertension. Multivariate analyses were used to identify factors associated with follow-up BP within 1 month of initial elevated BP. Among 72,625 children and adolescents in the population, 6108 (8.4%) had an incident elevated BP during the study period. Among 6108 with an incident elevated BP, 20.9% had a repeat BP measured within 1 month. In multivariate analyses, having a follow-up BP within 1 month was not significantly more likely among individuals with obesity or stage 2 systolic elevation. Among 6108 individuals with an incident elevated BP, 84 (1.4%) had a second and third consecutive elevated BP within 12 months. Whereas >8% of children and adolescents had an incident elevated BP, the great majority of BPs were not repeated within 1 month. However, relatively few individuals subsequently met the definition of hypertension.

  12. Investigation on cause of the elevator turbine wear

    Science.gov (United States)

    Zhang, J.; Ouyang, W. P.; Xue, J. A.

    2018-03-01

    Elevator traction turbine is often worn for various reasons, causing serious safety hazard. It is explained the main causes of traction wheel wear in detail in combination with a large number of engineering experience. The effect of turbine wear on the actual operation of the elevator is verified by contrast experiment, which is helpful to identify risks early. It is put forward on some reasonable suggestions for elevator inspection, maintenance and management.

  13. Unexpected Elevated Free Thyroid Hormones in Pregnancy.

    Science.gov (United States)

    Teti, Claudia; Nazzari, Elena; Galletti, Marina Raffaella; Mandolfino, Mattia Grazia; Pupo, Francesca; Pesce, Giampaola; Lillo, Flavia; Bagnasco, Marcello; Benvenga, Salvatore

    2016-11-01

    The use of thyrotropin and free thyroid hormone assays to evaluate thyroid function is widespread, but in some situations the results are inconsistent with the patient's thyroid status. A 35-year-old woman with a known diagnosis of chronic autoimmune thyroiditis was referred to the authors' clinic at week 26 of her second pregnancy. The patient was clinically euthyroid. Consistent with this, her serum thyrotropin (TSH) was normal (0.79 mIU/L), but she had elevated free thyroid hormones-free triiodothyronine (fT3) and free thyroxine (fT4)-as determined by a one-step chemiluminescent assay. The patient was taking levothyroxine replacement therapy (125 μg/day), and the dose was confirmed. Previous blood tests showed concordance between TSH and free thyroid hormone values. The patient was followed up throughout gestation and at 12 months postpartum. During gestation, her free thyroid hormones remained high using one-step methods, while the total thyroid hormone concentration values were within the reference range, in agreement with the TSH values. Postpartum fT4 and fT3 values returned progressively to normality, in agreement with the TSH values. The presence of circulating thyroid hormone autoantibodies (THAb) was hypothesized, which are known to interfere, although to a variable extent, with thyroid hormone one-step assays. Using stored frozen sera, this hypothesis was confirmed indirectly by measuring normal levels of fT3 and fT4 with a two-step method, and directly by demonstrating THAb against the two hormones. Despite their relative rarity, circulating THAb may be suspected when laboratory data are not consistent and contrast with the clinical picture. To the authors' knowledge, no previous case of transient appearance of THAb in pregnancy has been described.

  14. Geomorphic controls on elevational gradients of species richness.

    Science.gov (United States)

    Bertuzzo, Enrico; Carrara, Francesco; Mari, Lorenzo; Altermatt, Florian; Rodriguez-Iturbe, Ignacio; Rinaldo, Andrea

    2016-02-16

    Elevational gradients of biodiversity have been widely investigated, and yet a clear interpretation of the biotic and abiotic factors that determine how species richness varies with elevation is still elusive. In mountainous landscapes, habitats at different elevations are characterized by different areal extent and connectivity properties, key drivers of biodiversity, as predicted by metacommunity theory. However, most previous studies directly correlated species richness to elevational gradients of potential drivers, thus neglecting the interplay between such gradients and the environmental matrix. Here, we investigate the role of geomorphology in shaping patterns of species richness. We develop a spatially explicit zero-sum metacommunity model where species have an elevation-dependent fitness and otherwise neutral traits. Results show that ecological dynamics over complex terrains lead to the null expectation of a hump-shaped elevational gradient of species richness, a pattern widely observed empirically. Local species richness is found to be related to the landscape elevational connectivity, as quantified by a newly proposed metric that applies tools of complex network theory to measure the closeness of a site to others with similar habitat. Our theoretical results suggest clear geomorphic controls on elevational gradients of species richness and support the use of the landscape elevational connectivity as a null model for the analysis of the distribution of biodiversity.

  15. Effects of Elevated Carbon Dioxide on Litter Chemistry and Decomposition

    Data.gov (United States)

    National Aeronautics and Space Administration — The results of published and unpublished experiments investigating the impacts of elevated carbon dioxide on the chemistry (nitrogen and lignin concentration) of...

  16. Effects of Elevated Carbon Dioxide on Litter Chemistry and Decomposition

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: The results of published and unpublished experiments investigating the impacts of elevated carbon dioxide on the chemistry (nitrogen and lignin...

  17. Inferior ST-Elevation Myocardial Infarction Associated with Takotsubo Cardiomyopathy

    Directory of Open Access Journals (Sweden)

    Oliver Koeth

    2010-01-01

    Full Text Available Takotsubo cardiomyopathy (TCM is usually characterized by transient left ventricular apical ballooning. Due to the clinical symptoms which include chest pain, electrocardiographic changes, and elevated myocardial markers, Takotsubo cardiomyopathy is frequently mimicking ST-elevation myocardial infarction in the absence of a significant coronary artery disease. Otherwise an acute occlusion of the left anterior descending coronary artery can produce a typical Takotsubo contraction pattern. ST-elevation myocardial infarction (STEMI is frequently associated with emotional stress, but to date no cases of STEMI triggering TCM have been reported. We describe a case of a female patient with inferior ST-elevation myocardial infarction complicated by TCM.

  18. Hvordan understøttes hg-elevers kompetenceudvikling

    DEFF Research Database (Denmark)

    Svejgaard, Karin Løvenskjold; Hansen, Jens Ager; Karmark, Ole

    Publikationen handler om, hvordan hg-elever arbejder og dermed lærer og udvikler kvalifikationer og kompetencer i de undervisnings- og arbejdsformer, de indgår i. Indholdet er baseret på observationer af elever i klasseundervisning, gruppearbejde eller individuel arbejde i forlængelse af klasseun......Publikationen handler om, hvordan hg-elever arbejder og dermed lærer og udvikler kvalifikationer og kompetencer i de undervisnings- og arbejdsformer, de indgår i. Indholdet er baseret på observationer af elever i klasseundervisning, gruppearbejde eller individuel arbejde i forlængelse af...

  19. Ice Surfaces

    Science.gov (United States)

    Shultz, Mary Jane

    2017-05-01

    Ice is a fundamental solid with important environmental, biological, geological, and extraterrestrial impact. The stable form of ice at atmospheric pressure is hexagonal ice, Ih. Despite its prevalence, Ih remains an enigmatic solid, in part due to challenges in preparing samples for fundamental studies. Surfaces of ice present even greater challenges. Recently developed methods for preparation of large single-crystal samples make it possible to reproducibly prepare any chosen face to address numerous fundamental questions. This review describes preparation methods along with results that firmly establish the connection between the macroscopic structure (observed in snowflakes, microcrystallites, or etch pits) and the molecular-level configuration (detected with X-ray or electron scattering techniques). Selected results of probing interactions at the ice surface, including growth from the melt, surface vibrations, and characterization of the quasi-liquid layer, are discussed.

  20. Elevated temperature affects development, survivorship, and settlement of the elkhorn coral, Acropora palmata (Lamarck 1816).

    Science.gov (United States)

    Randall, Carly J; Szmant, Alina M

    2009-12-01

    Elevated seawater temperatures during the late summer have the potential to negatively affect the development and survivorship of the larvae of reef corals that are reproductive during that time of year. Acropora palmata, a major Caribbean hermatype, reproduces annually during August and September. A. palmata populations have severely declined over the past three decades, and recovery will require high recruitment rates. Such recruitment will be limited if larval supply is reduced by elevated temperatures. The effects of elevated temperatures on development, survival, and larval settlement of A. palmata were investigated by culturing newly fertilized eggs at temperatures ranging from 27.5 to 31.5 degrees C. Development was accelerated and the percentage of developmental abnormalities increased at higher temperatures. Embryo mortality peaked during gastrulation, indicating that this complex developmental process is particularly sensitive to elevated temperatures. Larvae cultured at 30 and 31.5 degrees C experienced as much as an 8-fold decrease in survivorship compared to those at 28 degrees C. Additionally, settlement was 62% at 28 degrees C compared to 37% at 31.5 degrees C. These results indicate that embryos and larvae of A. palmata will be negatively affected as sea surface temperatures continue to warm, likely reducing recruitment and the recovery potential of A. palmata on Caribbean reefs.

  1. A Review of the Effects of Elevated Temperature on Concrete Materials and Structures

    International Nuclear Information System (INIS)

    Naus, D.J.; Graves, H.L. III

    2006-01-01

    Concrete's properties are more complex than those of most materials because not only is concrete a composite material whose constituents have different properties, but its properties depend upon moisture and porosity. Exposure of concrete to elevated temperature affects its mechanical and physical properties. Elements could distort and displace, and, under certain conditions, the concrete surfaces could spall due to the buildup of steam pressure. Because thermally-induced dimensional changes, loss of structural integrity, and release of moisture and gases resulting from the migration of free water could adversely affect plant operations and safety, a complete understanding of the behavior of concrete under long-term elevated-temperature exposure as well as both during and after a thermal excursion resulting from a postulated design-basis accident condition is essential for reliable design evaluations and assessments of nuclear power plant structures. As the properties of concrete change with respect to time and the environment to which it is exposed, an assessment of the effects of concrete aging is also important in performing safety evaluations. The effects of elevated temperature on Portland cement concretes and constituent materials are summarized, design codes and standards identified, and considerations for elevated temperature service noted. (authors)

  2. Progress Toward Optimizing Prosthetic Socket Fit and Suspension Using Elevated Vacuum to Promote Residual Limb Health.

    Science.gov (United States)

    Wernke, Matthew M; Schroeder, Ryan M; Haynes, Michael L; Nolt, Lonnie L; Albury, Alexander W; Colvin, James M

    2017-07-01

    Objective: Prosthetic sockets are custom made for each amputee, yet there are no quantitative tools to determine the appropriateness of socket fit. Ensuring a proper socket fit can have significant effects on the health of residual limb soft tissues and overall function and acceptance of the prosthetic limb. Previous work found that elevated vacuum pressure data can detect movement between the residual limb and the prosthetic socket; however, the correlation between the two was specific to each user. The overall objective of this work is to determine the relationship between elevated vacuum pressure deviations and prosthetic socket fit. Approach: A tension compression machine was used to apply repeated controlled forces onto a residual limb model with sockets of different internal volume. Results: The vacuum pressure-displacement relationship was dependent on socket fit. The vacuum pressure data were sensitive enough to detect differences of 1.5% global volume and can likely detect differences even smaller. Limb motion was reduced as surface area of contact between the limb model and socket was maximized. Innovation: The results suggest that elevated vacuum pressure data provide information to quantify socket fit. Conclusions: This study provides evidence that the use of elevated vacuum pressure data may provide a method for prosthetists to quantify and monitor socket fit. Future studies should investigate the relationship between socket fit, limb motion, and limb health to define optimal socket fit parameters.

  3. Unraveling African plate structure from elevation, geoid and geology data

    Science.gov (United States)

    Chardon, Dominique; Bajolet, Flora; Robert, Alexandra; Rouby, Delphine

    2014-05-01

    The aim of our project is to simulate the long-wavelength, flexural isostatic response of the African plate to sediment transfers due to Meso-Cenozoic erosion - deposition processes in order to extract the residual topography driven by mantle dynamics. Our work will be based on the reconstruction and subtraction of two continental-scale erosional-depositional surfaces of Eocene and Late Cretaceous ages and their offshore extensions. The first step of our project consists in computing crustal and lithospheric maps of the African plate considering its various crustal geological components (cratons, mobile belts, basins, rifts and passive margins of various ages and strengths). In order to consider these heterogeneities, we compute a 2D distribution of crustal densities and thermal parameters from geological data and use it as an input of our modeling. We combine elevation and geoid anomaly data using a thermal analysis, following the method of Fullea et al. (2007) in order to map crustal and lithospheric thicknesses. In this approach, we assume local isostasy and consider a four-layer model made of crust and lithospheric mantle plus seawater and asthenosphere. In addition, we compare our results with crustal thickness datasets compiled from bibliography, existing global models such as CRUST 1.0, and tomographic lithospheric models. The obtained crustal thicknesses range from 30 to 45km, with the thickest crust confined to the northern part of the West African Craton, the Kaapvaal craton, and the Congo cuvette. The crust in the East African Rift appears unrealistically thick (40-45 km) as it is not isotatically compensated, highlighting the dynamic effect of the African superswell. The thinnest crust (30-35km) follows a central East-West trend coinciding with Cretaceous rifts and the Cameroon volcanic line. Pan-African mobile belts yield intermediate values of ca. 35-40 km. The lithosphere reaches 250 km beneath cratons, but remains globally thin (ca. 150-180 km

  4. Effects of prescribed burning on marsh-elevation change and the risk of wetland loss

    Science.gov (United States)

    McKee, Karen L.; Grace, James B.

    2012-01-01

    Marsh-elevation change is the net effect of biophysical processes controlling inputs versus losses of soil volume. In many marshes, accumulation of organic matter is an important contributor to soil volume and vertical land building. In this study, we examined how prescribed burning, a common marsh-management practice, may affect elevation dynamics in the McFaddin National Wildlife Refuge, Texas by altering organic-matter accumulation. Experimental plots were established in a brackish marsh dominated by Spartina patens, a grass found throughout the Gulf of Mexico and Atlantic marshes. Experimental plots were subjected to burning and nutrient-addition treatments and monitored for 3.5 years (April 2005 – November 2008). Half of the plots were burned once in 2006; half of the plots were fertilized seasonally with nitrogen, phosphorus, and potassium. Before and after the burns, seasonal measurements were made of soil physicochemistry, vegetation structure, standing and fallen plant biomass, aboveground and belowground production, decomposition, and accretion and elevation change (measured with Surface Elevation Tables (SET)). Movements in different soil strata (surface, root zone, subroot zone) were evaluated to identify which processes were contributing to elevation change. Because several hurricanes occurred during the study period, we also assessed how these storms affected elevation change rates. The main findings of this study were as follows: 1. The main drivers of elevation change were accretion on the marsh surface and subsurface movement below the root zone, but the relative influence of these processes varied temporally. Prior to Hurricanes Gustav and Ike (September 2008), the main driver was subsurface movement; after the hurricane, both accretion and subsurface movement were important. 2. Prior to Hurricanes Gustav and Ike, rates of elevation gain and accretion above a marker horizon were higher in burned plots compared to nonburned plots, whereas

  5. Diversity and feeding strategies of soil microfauna along elevation gradients in Himalayan cold deserts.

    Directory of Open Access Journals (Sweden)

    Miloslav Devetter

    Full Text Available High-elevation cold deserts in Tibet and Himalaya are one of the most extreme environments. One consequence is that the diversity of macrofauna in this environment is often limited, and soil microorganisms have a more influential role in governing key surface and subsurface bioprocesses. High-elevation soil microfauna represent important components of cold ecosystems and dominant consumers of microbial communities. Still little is known about their diversity and distribution on the edge of their reproductive and metabolic abilities. In this study, we disentangle the impact of elevation and soil chemistry on diversity and distribution of rotifers, nematodes and tardigrades and their most frequent feeding strategies (microbial filter-feeders, bacterivores, fungivores, root-fungal feeders, omnivores along two contrasting altitudinal gradients in Indian NW Himalaya (Zanskar transect from 3805 to 4714 m a.s.l. and southwestern Tibet (Tso Moriri transect from 4477 to 6176 m a.s.l., using a combination of multivariate analysis, variation partitioning and generalized additive models. Zanskar transect had higher precipitation, soil moisture, organic matter and available nutrients than dry Tso Moriri transect. In total, 40 species of nematodes, 19 rotifers and 1 tardigrade were discovered. Species richness and total abundance of rotifers and nematodes showed mid-elevation peaks in both investigated transects. The optimum for rotifers was found at higher elevation than for nematodes. Diversity and distribution of soil microfauna was best explained by soil nitrogen, phosphorus and organic matter. More fertile soils hosted more diverse and abundant faunal communities. In Tso Moriri, bacterivores represented 60% of all nematodes, fungivores 35%, root-fungal feeders 1% and omnivores 3%. For Zanskar the respective proportions were 21%, 13%, 56% and 9%. Elevational optima of different feeding strategies occurred in Zanskar in one elevation zone (4400-4500 m

  6. Diversity and feeding strategies of soil microfauna along elevation gradients in Himalayan cold deserts.

    Science.gov (United States)

    Devetter, Miloslav; Háněl, Ladislav; Řeháková, Klára; Doležal, Jiří

    2017-01-01

    High-elevation cold deserts in Tibet and Himalaya are one of the most extreme environments. One consequence is that the diversity of macrofauna in this environment is often limited, and soil microorganisms have a more influential role in governing key surface and subsurface bioprocesses. High-elevation soil microfauna represent important components of cold ecosystems and dominant consumers of microbial communities. Still little is known about their diversity and distribution on the edge of their reproductive and metabolic abilities. In this study, we disentangle the impact of elevation and soil chemistry on diversity and distribution of rotifers, nematodes and tardigrades and their most frequent feeding strategies (microbial filter-feeders, bacterivores, fungivores, root-fungal feeders, omnivores) along two contrasting altitudinal gradients in Indian NW Himalaya (Zanskar transect from 3805 to 4714 m a.s.l.) and southwestern Tibet (Tso Moriri transect from 4477 to 6176 m a.s.l.), using a combination of multivariate analysis, variation partitioning and generalized additive models. Zanskar transect had higher precipitation, soil moisture, organic matter and available nutrients than dry Tso Moriri transect. In total, 40 species of nematodes, 19 rotifers and 1 tardigrade were discovered. Species richness and total abundance of rotifers and nematodes showed mid-elevation peaks in both investigated transects. The optimum for rotifers was found at higher elevation than for nematodes. Diversity and distribution of soil microfauna was best explained by soil nitrogen, phosphorus and organic matter. More fertile soils hosted more diverse and abundant faunal communities. In Tso Moriri, bacterivores represented 60% of all nematodes, fungivores 35%, root-fungal feeders 1% and omnivores 3%. For Zanskar the respective proportions were 21%, 13%, 56% and 9%. Elevational optima of different feeding strategies occurred in Zanskar in one elevation zone (4400-4500 m), while in Tso Moriri

  7. A Seamless, High-Resolution, Coastal Digital Elevation Model (DEM) for Southern California

    Science.gov (United States)

    Barnard, Patrick L.; Hoover, Daniel

    2010-01-01

    A seamless, 3-meter digital elevation model (DEM) was constructed for the entire Southern California coastal zone, extending 473 km from Point Conception to the Mexican border. The goal was to integrate the most recent, high-resolution datasets available (for example, Light Detection and Ranging (Lidar) topography, multibeam and single beam sonar bathymetry, and Interferometric Synthetic Aperture Radar (IfSAR) topography) into a continuous surface from at least the 20-m isobath to the 20-m elevation contour. This dataset was produced to provide critical boundary conditions (bathymetry and topography) for a modeling effort designed to predict the impacts of severe winter storms on the Southern California coast (Barnard and others, 2009). The hazards model, run in real-time or with prescribed scenarios, incorporates atmospheric information (wind and pressure fields) with a suite of state-of-the-art physical process models (tide, surge, and wave) to enable detailed prediction of water levels, run-up, wave heights, and currents. Research-grade predictions of coastal flooding, inundation, erosion, and cliff failure are also included. The DEM was constructed to define the general shape of nearshore, beach and cliff surfaces as accurately as possible, with less emphasis on the detailed variations in elevation inland of the coast and on bathymetry inside harbors. As a result this DEM should not be used for navigation purposes.

  8. Surfacing Moves

    DEFF Research Database (Denmark)

    Lutz, Peter

    2013-01-01

    such as schedules, machines, and aging bodies. To this end, the article also experiments with ‘surfacing’ as an ethnographic heuristic for figuring these different ‘spatial-timings’. The article concludes that surfacing matters not only in senior home care but also in the field-desks of ethnographic analysis....

  9. Attack surfaces

    DEFF Research Database (Denmark)

    Gruschka, Nils; Jensen, Meiko

    2010-01-01

    The new paradigm of cloud computing poses severe security risks to its adopters. In order to cope with these risks, appropriate taxonomies and classification criteria for attacks on cloud computing are required. In this work-in-progress paper we present one such taxonomy based on the notion...... of attack surfaces of the cloud computing scenario participants....

  10. Budapest, Hungary, Perspective View, SRTM Elevation Model with Landsat Overlay

    Science.gov (United States)

    2004-01-01

    After draining the northern flank of the Alps Mountains in Germany and Austria, the Danube River flows east as it enters this west-looking scene (upper right) and forms the border between Slovakia and Hungary. The river then leaves the border as it enters Hungary and transects the Transdanubian Mountains, which trend southwest to northeast. Upon exiting the mountains, the river turns southward, flowing past Budapest (purplish blue area) and along the western margin of the Great Hungarian Plain.South and west of the Danube, the Transdanubian Mountains have at most only about 400 meters (about 1300 feet) of relief but they exhibit varied landforms, which include volcanic, tectonic, fluvial (river), and eolian (wind) features. A thick deposit of loess (dust deposits likely blown from ancient glacial outwash) covers much of this area, and winds from the northwest, funneled between the Alps and the Carpathian Mountains, are apparently responsible for a radial pattern of erosional streaks across the entire region.This image was generated from a Landsat satellite image draped over an elevation model produced by the Shuttle Radar Topography Mission (SRTM). The view uses a 3-times vertical exaggeration to enhance topographic expression. The false colors of the scene result from displaying Landsat bands 1, 4, and 7 in blue, green, and red, respectively. Band 1 is visible blue light, but bands 4 and 7 are reflected infrared light. This band combination maximizes color contrasts between the major land cover types, namely vegetation (green), bare ground (red), and water (blue). Shading of the elevation model was used to further highlight the topographic features.Elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on February 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space

  11. Surface Water Elevation and Quality, Peace-Athabasca Delta, Canada, 2006-2007

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: The Peace-Athabasca Delta (PAD) is a large boreal wetland located in northeastern Alberta, Canada at the confluence of the Peace and Athabasca Rivers with...

  12. Surface Water Elevation and Quality, Peace-Athabasca Delta, Canada, 2006-2007

    Data.gov (United States)

    National Aeronautics and Space Administration — The Peace-Athabasca Delta (PAD) is a large boreal wetland located in northeastern Alberta, Canada at the confluence of the Peace and Athabasca Rivers with Lake...

  13. Biogeochemicl and surface elevation controls over tidally influenced freshwater forested wetlands as they transition to marsh

    Science.gov (United States)

    William Conner; Ken W. Krauss; Gregory B. Noe; Jamie A. Duberstein; Nicole Cormier; Camille L. Stagg

    2016-01-01

    Many coastal ecosystems along the south Atlantic are transitioning from forested wetlands to marsh due to increasing tidal inundation and saltwater intrusion primarily attributed to global climate change processes. In 2004, we established long-term research sites in Georgia, South Carolina, and Louisiana to understand how climate factors (temperature, precipitation, ...

  14. Elevation of water table and various stratigraphic surfaces beneath e area low level waste disposal facility

    Energy Technology Data Exchange (ETDEWEB)

    Bagwell, Laura [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Bennett, Patti [; Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-11-02

    This memorandum describes work that supports revision of the Radiological Performance Assessment (PA) for the E Area Low Level Radioactive Waste Disposal Facility (LLRWDF). The work summarized here addresses portions of the PA Strategic Planning Team's recommendation #148b (Butcher and Phifer, 2016).

  15. IceBridge UAF Lidar Scanner L1B Geolocated Surface Elevation Triplets

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains contains scanning laser altimetry data points of Alaska Glaciers acquired using the airborne University of Alaska Fairbanks (UAF) Glacier...

  16. Surface Elevation Change And Vertical Accretion In Created Mangroves In Tampa Bay, Florida, Usa

    Science.gov (United States)

    Mangroves protect coastlines, provide faunal habitat, and store large quantities of carbon (C). In South Florida and other parts of the Gulf of Mexico, large wetland areas, including mangrove forests, have been removed, degraded, or damaged. Wetland creation efforts have been use...

  17. Diazepam treatment blocks the elevation of hippocampal activity and the accelerated proliferation of hippocampal neural stem cells after focal cerebral ischemia in mice.

    Science.gov (United States)

    Nochi, Rokuya; Kaneko, Jun; Okada, Natsumi; Terazono, Yasushi; Matani, Ayumu; Hisatsune, Tatsuhiro

    2013-11-01

    Hippocampal neurogenesis is accelerated during the elevation of hippocampal neural activities under both physiological and pathophysiological conditions. One of these conditions, middle cerebral artery occlusion (MCAO), induces both the hyperactivities of hippocampal network and the elevation of neural stem cell (NSC) proliferation. However, the causal relationship between the elevated activity and the elevation of NSC proliferation is still unclear. In this study, to block the elevation of hippocampal activity after MCAO in mice, we utilized a typical γ-aminobutyric acid type A (GABAA ) receptor active modulator, diazepam. With MCAO mice treated with diazepam, we observed complete disappearance of the elevation of hippocampal activity. Additionally, the diazepam treatment blocked the elevation of NSC proliferation after MCAO. From this result, it is speculated that the increased NSC proliferation is blocked by the suppression of elevated neural activity. However, diazepam might have effects other than the suppression of hippocampal activity, so we performed additional experiment and found that diazepam did not affect the number of bromodeoxyuridine-positive cells under the normal condition, whereas the GABA agonist pentobarbital stimulated NSC/neural progenitor cell proliferation and differentiation. Next, we evaluated the expression of the diazepam-binding inhibitor (DBI) protein and found that the cells expressed DBI in soma and on the surface of cell membrane. From these observations, we can propose that diazepam blocks the elevation of hippocampal activity and also NSC proliferation after MCAO. Copyright © 2013 Wiley Periodicals, Inc.

  18. Abundance and productivity of birds over an elevational gradient

    Science.gov (United States)

    Kathryn L. Purcell

    2002-01-01

    This study is investigating the abundance and productivity of birds breeding in four forest types over an elevational gradient in conifer forests of the southern Sierra Nevada of California to identify the most productive habitats for each species, and to examine elevational shifts in abundance, especially as they relate to temperature and precipitation. Species...

  19. Global warming, elevational ranges and the vulnerability of tropical biota

    NARCIS (Netherlands)

    Laurance, W.F.; Useche, D.C.; Shoo, L.P.; Herzog, S.K.; Kessler, M.; Escobar, F.; Brehm, G.; Axmacher, J.C.; Chen, I.-C.; Arrellano Gámez, L.; Hietz, P.; Fiedler, K.; Pyrcz, T.; Wolf, J.; Merkord, C.L.; Cardelus, C.; Marshall, A.R.; Ah-Peng, C.; Aplet, G.H.; del Coro Arizmendi, M.; Baker, W.J.; Barone, J.; Brühl, C.A.; Bussmann, R.W.; Cicuzza, D.; Eilu, G.; Favila, M.E.; Hemp, A.; Hemp, C.; Homeier, J.; Hurtado, J.; Jankowski, J.; Kattán, G.; Kluge, J.; Krömer, T.; Lees, D.C.; Lehnert, M.; Longino, J.T.; Lovett, J.; Martin, P.H.; Patterson, B.D.; Pearson, R.G.; Peh, K. S.-H.; Richardson, B.; Richardson, M.; Samways, M.J.; Senbeta, F.; Smith, T.B.; Utteridge, T.M.A.; Watkins, J.E.; Wilson, R.; Williams, S.E.; Thomas, C.D.

    2011-01-01

    Tropical species with narrow elevational ranges may be thermally specialized and vulnerable to global warming. Local studies of distributions along elevational gradients reveal small-scale patterns but do not allow generalizations among geographic regions or taxa. We critically assessed data from

  20. Synchronous Control Method and Realization of Automated Pharmacy Elevator

    Science.gov (United States)

    Liu, Xiang-Quan

    Firstly, the control method of elevator's synchronous motion is provided, the synchronous control structure of double servo motor based on PMAC is accomplished. Secondly, synchronous control program of elevator is implemented by using PMAC linear interpolation motion model and position error compensation method. Finally, the PID parameters of servo motor were adjusted. The experiment proves the control method has high stability and reliability.

  1. Læreren og udfordringerne med begavede og talentfulde elever

    DEFF Research Database (Denmark)

    Nissen, Poul

    2010-01-01

    Det er nu blevet stuerent at tale om de begavede og talentfulde elever i skolen. Artiklen diskuterer, hvilke elever, der kan betegnes som "talentfulde" eller med "særlige forudsætninger", og beskriver de problemer, som denne elevgruppe kan have. Samtidig påpeger forfatteren, at der mangler forskn...

  2. Læreren og udfordringerne med begavede og talentfulde elever

    DEFF Research Database (Denmark)

    Nissen, Poul

    2010-01-01

    På trods af, at Den danske Folkeskole er baseret på et enhedsskoleprincip ses aktuelt flere steder i landet, hvor der oprettes særlige tiltag for skolens bedst begavede og talentfulde elever. Enkelte danske undersøgelser tyder på, at en del velbegavede og talentfulde elever mistrives i skolen, me...

  3. Climber Motion Optimization for the Tethered Space Elevator

    NARCIS (Netherlands)

    Williams, P.; Ockels, W.J.

    The tethered space elevator could provide a revolutionary means for enabling cheap transportation to geostationary altitude and beyond. Assuming that such a system can be built, one of the dynamic design problems is determining a means of moving the elevator along the tether so as to minimize the

  4. Ecology and IPM of Insects at Grain Elevators

    Science.gov (United States)

    Cost-effectiveness of insect pest management depends upon its integration with other elevator operations. Successful integration may require consideration of insect ecology. Field infestation has not been observed for grain received at elevators. Grain may be infested during harvest by residual inse...

  5. Influence of elevator acceleration induced loading on injury levels

    NARCIS (Netherlands)

    Funai, K.; Schijndel-de Nooij, M. van; Nunen, E. van

    2008-01-01

    The influence on human body of the acceleration caused by the elevator emergency stop has been studied. Experiments were performed with an automotive dummy in an elevator. The study is furthermore based on numerical simulations in MADYMO with an active human model. Kinematics and contact forces of

  6. The hidden magnitude of raised blood pressure and elevated blood ...

    African Journals Online (AJOL)

    Conclusions: The prevalence of undiagnosed raised blood pressure and elevated blood sugar was high in Ethiopia and only very small percentage of people had been aware of their high blood pressure and elevated blood sugar. Policy makers in the health sector including other health development partners need to ...

  7. 47 CFR 25.205 - Minimum angle of antenna elevation.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Minimum angle of antenna elevation. 25.205... SATELLITE COMMUNICATIONS Technical Standards § 25.205 Minimum angle of antenna elevation. (a) Earth station antennas shall not normally be authorized for transmission at angles less than 5° measured from the...

  8. A technique of the structural-tectonic elevations prediction using Earth remote sensing data

    Science.gov (United States)

    Tishaev, I. V.; Zatserkovnyi, V. I.; Yagorlytska, K. P.

    2016-12-01

    We consider an approach of using methods of Earth remote sensing data (RSD) classification for solving tasks of exploration geology and geophysics. Information obtained from the remote sensing data gives a possibility to clarify the structure of investigated areas and to determine neotectonic elevations, which act as certain indicators of promising areas with hydra-carbons contents. Reasonability of using such methods of RSD classification is based on connection between deep structure of surface resources (structural-tectonic setting) with current landscape, character of hydrologic network, geo-morphological, geo-botanical and other features. The advantage of Bayes classificator is not only in determination of object belonging to certain class, but also in calculation of probability of such belonging. For the formulated task this lets to forecast a presence of structural-tectonic elevations, which are potentially promising areas for hydra-carbons contents, using a formali! zed quantitative criterion. contents.

  9. Decomposition reactions in RDX at elevated temperatures and pressures

    Science.gov (United States)

    Schweigert, Igor

    2015-03-01

    Mechanisms and rates of elementary reactions controlling condensed-phase decomposition of RDX under elevated temperatures (up to 2000 K) and pressures (up to a few GPa) are not known. Global decomposition kinetics in RDX below 700 K has been measured; however, the observed global pathways result from complex manifolds of elementary reactions and are likely to be altered by elevated temperatures. Elevated pressures can further affect the condensed-phase kinetics and compete with elevated temperatures in promoting some elementary reactions and suppressing others. This presentation will describe density functional theory (DFT) based molecular dynamics simulations of crystalline and molten RDX aimed to delineate the effects of elevated temperatures and pressures on the mechanism of initial dissociation and the resulting secondary reactions. This work was supported by the Naval Research Laboratory, by the Office of Naval Research, and by the DOD High Performance Computing Modernization Program Software Application Institute for Multiscale Reactive Modeling of Insensitive Munitions.

  10. Etiology and Therapeutic Approach to Elevated Lactate Levels

    DEFF Research Database (Denmark)

    Wiuff Andersen, Lars; Mackenhauer, Julie; Roberts, Jonathan C

    2013-01-01

    Lactate levels are commonly evaluated in acutely ill patients. Although most often used in the context of evaluating shock, lactate levels can be elevated for many reasons. While tissue hypoperfusion may be the most common cause of elevation, many other etiologies or contributing factors exist....... Clinicians need to be aware of the many potential causes of lactate level elevation as the clinical and prognostic importance of an elevated lactate level varies widely by disease state. Moreover, specific therapy may need to be tailored to the underlying cause of elevation. The present review is based...... on a comprehensive PubMed search between the dates of January 1, 1960, to April 30, 2013, using the search term lactate or lactic acidosis combined with known associations, such as shock, sepsis, cardiac arrest, trauma, seizure, ischemia, diabetic ketoacidosis, thiamine, malignancy, liver, toxins, overdose...

  11. Myoelectric manifestations of jaw elevator muscle fatigue and recovery in healthy and TMD subjects.

    Science.gov (United States)

    Castroflorio, T; Falla, D; Tartaglia, G M; Sforza, C; Deregibus, A

    2012-09-01

    The effects of muscle pain and fatigue on the control of jaw elevator muscles are not well known. Furthermore, the myoelectric manifestations of fatigue and recovery from fatigue in the masticatory muscles are not reported in literature. The main aims of this study were (i) to evaluate the possible use of surface electromyography (sEMG) as an objective measure of fatigue of the jaw elevator muscles, (ii) to compare the myoelectric manifestations of fatigue in the temporalis anterior and masseter muscles bilaterally, (iii) to assess recovery of the investigated muscles after an endurance test and (iv) to compare fatigue and recovery of the jaw elevator muscles in healthy subjects and patients with muscle-related temporomandibular disorders (TMD). The study was performed on twenty healthy volunteers and eighteen patients with muscle-related TMD. An intra-oral compressive-force sensor was used to measure the voluntary contraction forces close to the intercuspal position and to provide visual feedback of submaximal forces to the subject. Surface EMG signals were recorded with linear electrode arrays during isometric contractions at 20%, 40%, 60% and 80% of the maximum voluntary contraction force, during an endurance test and during the recovery phase. The results showed that (i) the slope of the mean power spectral frequency (MNF) and the initial average rectified value (ARV) could be used to monitor fatigue of the jaw elevators, (ii) the temporalis anterior and masseter muscle show the same myoelectric manifestations of fatigue and recovery and (iii) the initial values of MNF and ARV were lower in patients with muscle-related TMD. The assessment of myoelectric manifestations of fatigue in the masticatory muscles may assist in the clinical assessment of TMDs. © 2012 Blackwell Publishing Ltd.

  12. Low-latitude high elevation of the leading edge of southern Eurasia throughout the Cenozoic

    Science.gov (United States)

    Ingalls, M.; Rowley, D. B.; Colman, A. S.; Olack, G.; Currie, B.; Li, S.

    2016-12-01

    The elevation history of the Tibetan Plateau promises insight into the mechanisms and dynamics that develop and sustain high topography over tens of millions of years. We present the first continuous Cenozoic elevation history from two proximal sedimentary basins on the southern Tibetan Plateau, as well as preliminary paleoaltimetry results from the south-central and central Plateau (Sangsang and Lunpola). The oxygen stable isotope and Δ47 clumped isotope compositions of non-marine carbonates allow us to constrain the carbonate formation temperatures and reconstruct the paleo-precipitation record of the Eocene to Pliocene Oiyug Basin and Paleocene to Eocene Penbo Basin. We exploit the systematic decrease of surface temperature and meteoric water δ18O with elevation. Minimally altered and unaltered pedogenic carbonates from the Oiyug Basin yield Δ47, CDES values of 0.625 to 0.755, that correspond with temperatures of 1-30 °C using a (Zaarur et al., 2013) Δ47 thermometer for low temperature carbonates. Similarly, the Penbo Basin yields Δ47, CDES values of 0.700-0.730, corresponding with temperatures of 6-12°C. Our paleoelevation estimates for the well-studied Oiyug basin ( 6100-4200 meters) support previous evidence (Spicer et al., 2003; Currie et al., 2005; Polissar et al., 2009; Currie et al., 2016) that high elevations were attained in southern Tibet by at least 30 Ma. Our paleoelevation estimates for the Penbo Basin (4100±550 meters) extends the altitude record of the southern Plateau to pre-India-Asia collision. Preliminary results from Sangsang, further west along the Indus-Yarlung Suture, and Lunpola, on the central Plateau, allow us to develop a spatially and temporally more complex paleo-altitude map and land surface evolution of the Tibetan Plateau since the onset of continent-continent collision.

  13. Model for the Evolving Bed Surface around an Offshore Monopile

    DEFF Research Database (Denmark)

    Hartvig, Peres Akrawi

    2012-01-01

    This paper presents a model for the bed surface around an offshore monopile. The model has been designed from measured laboratory bed surfaces and is shown to reproduce these satisfactorily for both scouring and backfilling. The local rate of the bed elevation is assumed to satisfy a certain gene...

  14. A full coverage, high-resolution, topographic model of Greenland computed from a variety of digital elevation data

    DEFF Research Database (Denmark)

    Ekholm, Simon

    1996-01-01

    In this paper, a new high-resolution elevation model of Greenland, including the ice sheet as well as the ice free regions, is presented. It is the first published full coverage model, computed with an average resolution of 2 km and providing an unprecedented degree of detail. The topography...... airborne laser data from the analysis and treating them as ground truth observations. The mean accuracy of the ice sheet elevations is estimated to be 12-13 m, and it is found that on surfaces of a slope between 0.2 degrees and 0.8 degrees, corresponding to approximately 50% of the ice sheet, the model...

  15. Glacial erosion of high-elevation low-relief summits on passive continental margins constrained by cosmogenic nuclides

    DEFF Research Database (Denmark)

    Andersen, Jane Lund; Egholm, David Lundbek; Knudsen, Mads Faurschou

    We present a new, extensive in-situ cosmogenic 10Be and 26Al dataset from high-elevation low-relief summits along Sognefjorden in Norway. Contrary to previous studies of high-elevation low-relief summits in cold regions, we find only limited cosmogenic nuclide inheritance in bedrock surfaces......, indicating that warm-based ice eroded the summits during the last glacial period. From the isotope concentrations we model denudation histories using a recently developed Monte Carlo Markov Chain inversion model (Knudsen et al, 2015). The model relies on the benthic d18O curve (Lisiecki and Raymo, 2005...

  16. A Person Stands on a Balance in an Elevator: What Happens When the Elevator Starts to Fall?

    Science.gov (United States)

    Balukovic, Jasmina; Slisko, Josip; Cruz, Adrián Corona

    2018-01-01

    Physics textbook authors commonly introduce the concept of weightlessness (apparent or real) through a "thought experiment" in which a person weighs herself or himself in an elevator. When the elevator falls freely, the spring balance should show zero weight. There is an unresolved controversy about how this "zero reading"…

  17. Impacts of elevated atmospheric CO2 on forest trees and forest ecosystems: knowledge gaps

    International Nuclear Information System (INIS)

    Karnosky, D.F.

    2003-06-01

    Atmospheric CO 2 is rising rapidly, and options for slowing the CO 2 rise are politically charged as they largely require reductions in industrial CO 2 emissions for most developed countries. As forests cover some 43% of the Earth's surface, account for some 70% of terrestrial net primary production (NPP), and are being bartered for carbon mitigation, it is critically important that we continue to reduce the uncertainties about the impacts of elevated atmospheric CO 2 on forest tree growth, productivity, and forest ecosystem function. In this paper, 1 review knowledge gaps and research needs on the effects of elevated atmospheric CO 2 on forest above- and below-ground growth and productivity, carbon sequestration, nutrient cycling, water relations, wood quality, phonology, community dynamics and biodiversity, antioxidants and stress tolerance, interactions with air pollutants, heterotrophic interactions, and ecosystem functioning. Finally, 1 discuss research needs regarding modelling of the impacts of elevated atmospheric CO 2 on forests. Even though there has been a tremendous amount of research done with elevated CO 2 and forest trees, it remains difficult to predict future forest growth and productivity under elevated atmospheric CO 2 . Likewise, it is not easy to predict how forest ecosystem processes will respond to enriched CO 2 . The more we study the impacts of increasing CO 2 , the more we realize that tree and forest responses are yet largely uncertain due to differences in responsiveness by species, genotype, and functional group, and the complex interactions of elevated atmospheric CO 2 with soil fertility, drought, pests, and co-occurring atmospheric pollutants such as nitrogen deposition and O 3 . Furthermore, it is impossible to predict ecosystem-level responses based on short-term studies of young trees grown without interacting stresses and in small spaces without the element of competition. Long-term studies using free-air CO 2 enrichment (FACE

  18. EFFECTS OF ELEVATED CO2 ON ROOT FUNCTION AND SOIL RESPIRATION IN A MOJAVE DESERT ECOSYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    Nowak, Robert S.

    2007-12-19

    Increases in atmospheric CO{sub 2} concentration during the last 250 years are unequivocal, and CO{sub 2} will continue to increase at least for the next several decades (Houghton et al. 2001, Keeling & Whorf 2002). Arid ecosystems are some of the most important biomes globally on a land surface area basis, are increasing in area at an alarming pace (Dregne 1991), and have a strong coupling with regional climate (Asner & Heidebrecht 2005). These water-limited ecosystems also are predicted to be the most sensitive to elevated CO{sub 2}, in part because they are stressful environments where plant responses to elevated CO{sub 2} may be amplified (Strain & Bazzaz 1983). Indeed, all C{sub 3} species examined at the Nevada Desert FACE Facility (NDFF) have shown increased A{sub net} under elevated CO{sub 2} (Ellsworth et al. 2004, Naumburg et al. 2003, Nowak et al. 2004). Furthermore, increased shoot growth for individual species under elevated CO{sub 2} was spectacular in a very wet year (Smith et al. 2000), although the response in low to average precipitation years has been smaller (Housman et al. 2006). Increases in perennial cover and biomass at the NDFF are consistent with long term trends in the Mojave Desert and elsewhere in the Southwest, indicating C sequestration in woody biomass (Potter et al. 2006). Elevated CO{sub 2} also increases belowground net primary production (BNPP), with average increases of 70%, 21%, and 11% for forests, bogs, and grasslands, respectively (Nowak et al. 2004). Although detailed studies of elevated CO{sub 2} responses for desert root systems were virtually non-existent prior to our research, we anticipated that C sequestration may occur by desert root systems for several reasons. First, desert ecosystems exhibit increases in net photosynthesis and primary production at elevated CO{sub 2}. If large quantities of root litter enter the ecosystem at a time when most decomposers are inactive, significant quantities of carbon may be stored

  19. Influence of solar elevation in radiometric and geometric performance of multispectral photogrammetry

    Science.gov (United States)

    Honkavaara, Eija; Markelin, Lauri; Rosnell, Tomi; Nurminen, Kimmo

    2012-01-01

    Solar elevation is an important factor in passive, airborne data collection. The minimum solar elevation allowed in missions for topographic mapping is typically 30° from the horizon. A general hypothesis is that the new, high dynamic range, digital large-format photogrammetric sensors allow for high data quality, even with lower solar elevations, which would improve the feasibility and cost-efficiency of photogrammetric technology in various applications. Objectives of this study were to investigate theoretically and empirically the impacts of solar elevation in modern photogrammetric processes. Two cutting-edge aspects of novel photogrammetric technology were considered: point cloud creation by automatic image matching and reflectance calibration of image data. For the empirical study, we used image data collected by a large-format photogrammetric camera, Intergraph DMC, with low (25-28°) and medium (44-48°) solar elevations from 2, 3 and 4 km heights. We did not detect negative influences of decreasing solar elevation during our general evaluations: an analysis of image histograms showed that the ranges of digital numbers could be tuned to similar levels with exposure settings, and evaluations of density and the accuracy of point clouds did not show any reduction of quality. We carried out detailed evaluations in forests, roads and fields. Our results did not indicate deterioration of the quality in sun-illuminated areas with decreasing solar elevation. In shadowed areas, we observed that the variation of image signal was reduced in comparison to sun-illuminated areas and emphasized the issue of complication of reflectance calibration. Artefacts appeared in automatically generated point clouds in areas shadowed by trees, which we observed in flat objects as up to 3 times increased random height variation and decreased success in measuring the terrain surface. Our results also showed that the overall performance of point cloud generation was high. Typically

  20. Differentiating ST elevation myocardial infarction and nonischemic causes of ST elevation by analyzing the presenting electrocardiogram

    DEFF Research Database (Denmark)

    Jayroe, Jason B; Spodick, David H; Nikus, Kjell

    2008-01-01

    Guidelines recommend that patients with suggestive symptoms of myocardial ischemia and ST-segment elevation (STE) in > or =2 adjacent electrocardiographic leads should receive immediate reperfusion therapy. Novel strategies aimed to reduce door-to-balloon time, such as prehospital wireless...... electrocardiographic transmission, may be dependent on the interpretation accuracy of the electrocardiogram (ECG) readers. We assessed the ability of experienced electrocardiographers to differentiate among STE, acute STE myocardial infarction (STEMI), and nonischemic STE (NISTE). A total of 116 consecutive ECGs.......13). The sensitivity and specificity of the individual readers ranged from 50% to 100% (average 75%) and 73% to 97% (average 85%), respectively. There were broad inconsistencies among the readers in the chosen reasons used to classify NISTE. In conclusion, we found wide variations among experienced...