Sample records for national deep submergence

  1. Near-bottom Multibeam Survey Capabilities in the US National Deep Submergence Facility (Invited)

    NASA Astrophysics Data System (ADS)

    Yoerger, D. R.; McCue, S. J.; Jason; Sentry Operations Groups

    2010-12-01

    The US National Deep Submergence Facility (NDSF) provides near-bottom multibeam mapping capabilities from the autonomous underwater vehicle Sentry and the remotely operated vehicle Jason. These vehicles can be used to depths of 4500 and 6500m respectively. Both vehicles are equipped with Reson 7125 400khz multibeam sonars as well as compatible navigation equipment (inertial navigation systems, doppler velocity logs, and acoustic navigation systems). These vehicles have produced maps of rugged Mid-Ocean Ridge terrain in the Galapagos Rift, natural oil and gas seeps off the coast of Southern California, deep coral sites in the Gulf of Mexico, and sites for the Ocean Observing Initiative off the coast of Oregon. Multibeam surveys are conducted from heights between 20 and 80 meters, allowing the scientific user to select the tradeoff between resolution and coverage rate. In addition to conventional bathymetric mapping, the systems have used to image methane bubble plumes from natural seeps. This talk will provide summaries of these mapping efforts and describe the data processing pipeline used to produce maps shortly after each dive. Development efforts to reduce navigational errors and reconcile discrepancies between adjacent swaths will also be described.

  2. Can submerged macrophytes influence turbidity and trophic state in deep lakes? Suggestions from a case study.

    PubMed

    Hilt, Sabine; Henschke, Ingo; Rücker, Jacqueline; Nixdorf, Brigitte

    2010-01-01

    Feedback between submerged macrophytes and water transparency stabilizing the clear, macrophyte-dominated regime has been described so far for shallow lakes. Based on data of total phosphorus (TP) concentrations, underwater light supply, phytoplankton and submerged macrophyte abundance from narrow, stratified Lake Scharmützelsee (mean depth: 9 m, retention time: 16 yr) of the period 1994-2006 we hypothesize that submerged macrophytes may influence transparency and trophic state in deep lakes. The lake was characterized by summer epilimnion TP concentrations of 38 to 57 mug L(-1), turbid water due to mass development of cyanobacteria, and low abundance of few submerged macrophyte species until 2003. Thereafter, a sudden increase in water transparency was followed by a rapid submerged macrophyte colonization of the littoral down to about 5 m depth corresponding to the depth of a light supply of 3 E m(-2) d(-1). Initially, this recolonization was probably a consequence of decreased turbidity. We argue that the increase of submerged macrophyte coverage from < 10% in 1994 to 2003 to about 24% in 2005-2006 has contributed to the stabilization of the clear-water regime during the subsequent years. This is supported by the fact that earlier shifts to clear-water regimes in 1994 and 2000 without a significant spread of submerged macrophytes were not stable. We discuss potential mechanisms that may have resulted in a positive effect of plants on transparency such as P uptake and immobilization by the dominant rootless macrophyte species Nitellopsis obtusa and Ceratophyllum demersum and other macrophyte-related mechanisms such as increased zooplankton grazing and allelopathy.

  3. New Web Services for Broader Access to National Deep Submergence Facility Data Resources Through the Interdisciplinary Earth Data Alliance

    NASA Astrophysics Data System (ADS)

    Ferrini, V. L.; Grange, B.; Morton, J. J.; Soule, S. A.; Carbotte, S. M.; Lehnert, K.

    2016-12-01

    The National Deep Submergence Facility (NDSF) operates the Human Occupied Vehicle (HOV) Alvin, the Remotely Operated Vehicle (ROV) Jason, and the Autonomous Underwater Vehicle (AUV) Sentry. These vehicles are deployed throughout the global oceans to acquire sensor data and physical samples for a variety of interdisciplinary science programs. As part of the EarthCube Integrative Activity Alliance Testbed Project (ATP), new web services were developed to improve access to existing online NDSF data and metadata resources. These services make use of tools and infrastructure developed by the Interdisciplinary Earth Data Alliance (IEDA) and enable programmatic access to metadata and data resources as well as the development of new service-driven user interfaces. The Alvin Frame Grabber and Jason Virtual Van enable the exploration of frame-grabbed images derived from video cameras on NDSF dives. Metadata available for each image includes time and vehicle position, data from environmental sensors, and scientist-generated annotations, and data are organized and accessible by cruise and/or dive. A new FrameGrabber web service and service-driven user interface were deployed to offer integrated access to these data resources through a single API and allows users to search across content curated in both systems. In addition, a new NDSF Dive Metadata web service and service-driven user interface was deployed to provide consolidated access to basic information about each NDSF dive (e.g. vehicle name, dive ID, location, etc), which is important for linking distributed data resources curated in different data systems.

  4. The USGS role in mapping the nation's submerged lands

    USGS Publications Warehouse

    Schwab, Bill; Haines, John

    2004-01-01

    The seabed provides habitat for a diverse marine life having commercial, recreational, and intrinsic value. The habitat value of the seabed is largely a function of the geological structure and related geological, biological, oceanologic, and geochemical processes. Of equal importance, the nation's submerged lands contain energy and mineral resources and are utilized for the siting of offshore infrastructure and waste disposal. Seabed character and processes influence the safety and viability of offshore operations. Seabed and subseabed characterization is a prerequisite for the assessment, protection, and utilization of both living and non-living marine resources. A comprehensive program to characterize and understand the nation's submerged lands requires scientific expertise in the fields of geology, biology, hydrography, and oceanography. The U.S. Geological Survey (USGS) has long experience as the Federal agency charged with conducting geologic research and mapping in both coastal and offshore regions. The USGS Coastal and Marine Geology Program (CMGP) leads the nation in expertise related to characterization of seabed and subseabed geology, geological processes, seabed dynamics, and (in collaboration with the National Oceanic and Atmospheric Administration (NOAA) and international partners) habitat geoscience. Numerous USGS studies show that sea-floor geology and processes determine the character and distribution of biological habitats, control coastal evolution, influence the coastal response to storm events and human alterations, and determine the occurrence and concentration of natural resources.

  5. WHOI and SIO (I): Next Steps toward Multi-Institution Archiving of Shipboard and Deep Submergence Vehicle Data

    NASA Astrophysics Data System (ADS)

    Detrick, R. S.; Clark, D.; Gaylord, A.; Goldsmith, R.; Helly, J.; Lemmond, P.; Lerner, S.; Maffei, A.; Miller, S. P.; Norton, C.; Walden, B.

    2005-12-01

    The Scripps Institution of Oceanography (SIO) and the Woods Hole Oceanographic Institution (WHOI) have joined forces with the San Diego Supercomputer Center to build a testbed for multi-institutional archiving of shipboard and deep submergence vehicle data. Support has been provided by the Digital Archiving and Preservation program funded by NSF/CISE and the Library of Congress. In addition to the more than 92,000 objects stored in the SIOExplorer Digital Library, the testbed will provide access to data, photographs, video images and documents from WHOI ships, Alvin submersible and Jason ROV dives, and deep-towed vehicle surveys. An interactive digital library interface will allow combinations of distributed collections to be browsed, metadata inspected, and objects displayed or selected for download. The digital library architecture, and the search and display tools of the SIOExplorer project, are being combined with WHOI tools, such as the Alvin Framegrabber and the Jason Virtual Control Van, that have been designed using WHOI's GeoBrowser to handle the vast volumes of digital video and camera data generated by Alvin, Jason and other deep submergence vehicles. Notions of scalability will be tested, as data volumes range from 3 CDs per cruise to 200 DVDs per cruise. Much of the scalability of this proposal comes from an ability to attach digital library data and metadata acquisition processes to diverse sensor systems. We are able to run an entire digital library from a laptop computer as well as from supercomputer-center-size resources. It can be used, in the field, laboratory or classroom, covering data from acquisition-to-archive using a single coherent methodology. The design is an open architecture, supporting applications through well-defined external interfaces maintained as an open-source effort for community inclusion and enhancement.

  6. Production and characterization of bioactive metabolites from piezotolerant deep sea fungus Nigrospora sp. in submerged fermentation.

    PubMed

    Arumugam, G K; Srinivasan, S K; Joshi, G; Gopal, D; Ramalingam, K

    2015-01-01

    To produce and characterize bioactive metabolites from piezotolerant marine fungus Nigrospora sp. in submerged fermentation. A distinct marine strain, Nigrospora sp. NIOT has been isolated from a depth of 800 m at the Arabian Sea. The 18S rRNA and internal transcribed spacers (ITS) analysis demonstrates its close association with the genus Nigrospora. Effect of pH, temperature, salinity, carbon source and amino acids was studied to optimize the fermentation conditions. Optimal mycelia growth and secondary metabolites production were observed at 6·0-8·0 pH, 20-30°C temperature, 7·5% salinity, sucrose as carbon source and tryptophan as amino acid source. The extracellular secondary metabolites exhibited high antimicrobial activities against both gram-positive and gram-negative pathogenic bacteria with minimal inhibitory concentration (MIC) values higher than 30 μg ml(-1). Strongest cytotoxicity was observed in all cell lines tested, GI50 (growth inhibition by 50%) was calculated to be 1·35, 3·2, 0·13 and 0·35 μg ml(-1) against U937, MCF-7, A673 and Jurkat, respectively. Fourier transform infrared spectroscopy (FTIR) and gas chromatography-mass spectrometry (GC-MS) analyses of secondary metabolites confirmed the production of antimicrobial and anticancer substances. A piezotolerant fungus Nigrospora sp. NIOT isolated from deep sea environment was successfully cultured under submerged fermentation. The secondary metabolites produced from this organism showed potent antimicrobial and anticancer activities with immediate application to cosmetics and pharmaceutical industries. This is the first study exploring Nigrospora sp. from 800 m in marine environment. This deep sea fungus under optimized culture conditions effectively produced bioactive secondary metabolites such as griseofulvin, spirobenzofuran and pyrone derivatives at higher concentrations. © 2014 The Society for Applied Microbiology.

  7. Part of evanescent modes in the normally incident gravity surface wave's energy layout around a submerged obstacle

    NASA Astrophysics Data System (ADS)

    Charland, J.; Rey, V.; Touboul, J.

    2012-04-01

    Part of evanescent modes in the normally incident gravity surface wave's energy layout around a submerged obstacle Jenna Charland *1, Vincent Rey *2, Julien Touboul *2 *1 Mediterraneen Institute of Oceanography. Institut des Sciences de l'Ingénieur Toulon-Var. Avenue Georges Pompidou, BP 56, 83162 La Valette du Var Cedex, France. Centre National de la Recherche Scientifique, Délégation Normandie. Projet soutenu financièrement par la Délégation Générale de l'Armement. *2 Mediterraneen Institute of Oceanography. Institut des Sciences de l'Ingénieur Toulon-Var. Avenue Georges Pompidou, BP 56, 83162 La Valette du Var Cedex, France. During the last decades various studies have been performed to understand the wave propagation over varying bathymetries. Few answers related to this non linear problem were given by the Patarapanich's studies which described the reflection coefficient of a submerged plate as a function of the wavelength. Later Le-Thi-Minh [2] demonstrated the necessity of taking into account the evanescent modes to better describe the propagation of waves over a varying bathymetry. However, all these studies stare at pseudo-stationary state that allows neither the comprehension of the transient behaviour of propagative modes nor the role of the evanescent modes in this unstationnary process. Our study deals with the wave establishment over a submerged plate or step and focuses on the evanescent modes establishment. Rey [3] described the propagation of a normally incident surface gravity wave over a varying topography on the behaviour of the fluid using a linearized potential theory solved by a numerical model using an integral method. This model has a large field of application and has been adapted to our case. This code still solves a stationary problem but allows us to calculate the contribution of the evanescent modes in the energy layout around a submerged plate or a submerged step. The results will show the importance of the trapped energy

  8. Bed load transport by submerged jets

    PubMed Central

    Francis, J. R. D.; McCreath, P. S.

    1979-01-01

    Some similarities are presented between the bed load transport of noncohesive grains in long rivers and at a local, jet-induced scour. Experiments are described in which a submerged two-dimensional slot nozzle, inclined downward, eroded a deep sand bed. The rate of erosion at the very beginning of a scour was evaluated and compared with river data by use of the idea of “stream-power.” Empirical relationships for the two cases are similar, although the geometry of the boundaries is quite different. PMID:16592696

  9. Automated Generation of Geo-Referenced Mosaics From Video Data Collected by Deep-Submergence Vehicles: Preliminary Results

    NASA Astrophysics Data System (ADS)

    Rhzanov, Y.; Beaulieu, S.; Soule, S. A.; Shank, T.; Fornari, D.; Mayer, L. A.

    2005-12-01

    Many advances in understanding geologic, tectonic, biologic, and sedimentologic processes in the deep ocean are facilitated by direct observation of the seafloor. However, making such observations is both difficult and expensive. Optical systems (e.g., video, still camera, or direct observation) will always be constrained by the severe attenuation of light in the deep ocean, limiting the field of view to distances that are typically less than 10 meters. Acoustic systems can 'see' much larger areas, but at the cost of spatial resolution. Ultimately, scientists want to study and observe deep-sea processes in the same way we do land-based phenomena so that the spatial distribution and juxtaposition of processes and features can be resolved. We have begun development of algorithms that will, in near real-time, generate mosaics from video collected by deep-submergence vehicles. Mosaics consist of >>10 video frames and can cover 100's of square-meters. This work builds on a publicly available still and video mosaicking software package developed by Rzhanov and Mayer. Here we present the results of initial tests of data collection methodologies (e.g., transects across the seafloor and panoramas across features of interest), algorithm application, and GIS integration conducted during a recent cruise to the Eastern Galapagos Spreading Center (0 deg N, 86 deg W). We have developed a GIS database for the region that will act as a means to access and display mosaics within a geospatially-referenced framework. We have constructed numerous mosaics using both video and still imagery and assessed the quality of the mosaics (including registration errors) under different lighting conditions and with different navigation procedures. We have begun to develop algorithms for efficient and timely mosaicking of collected video as well as integration with navigation data for georeferencing the mosaics. Initial results indicate that operators must be properly versed in the control of the

  10. The negative effects of cadmium on Bermuda grass growth might be offset by submergence.

    PubMed

    Tan, Shuduan; Huang, Huang; Zhu, Mingyong; Zhang, Kerong; Xu, Huaqin; Wang, Zhi; Wu, Xiaoling; Zhang, Quanfa

    2013-10-01

    Revegetation in the water-level-fluctuation zone (WLFZ) could stabilize riverbanks, maintain local biodiversity, and improve reservoir water quality in the Three Gorges Reservoir Region (TGRR). However, submergence and cadmium (Cd) may seriously affect the survival of transplantations. Bermuda grass (Cynodon dactylon) is a stoloniferous and rhizomatous prostrate weed displaying high growth rate. A previous study has demonstrated that Bermuda grass can tolerate deep submergence and Cd stress, respectively. In the present study, we further analyzed physiological responses of Bermuda grass induced by Cd-and-submergence stress. The ultimate goal was to explore the possibility of using Bermuda grass for revegetation in the WLFZ of China's TGRR and other riparian areas. The Cd-and-submergence-treated plants had higher malondialdehyde contents and peroxidase than control, and both increased with the Cd concentration increase. All treated plants catalase activity increased with the experimental duration increases, and their superoxide dismutase also gradually increased with the Cd concentration from 1 day to 15 days. Total biomass of the same Cd-and-submergence plants increased along the experimental duration as well. Plants exposed to Cd-and-submergence stress showed shoot elongation. The heights of all treated plants were taller than those of the control. Leaf chlorophyll contents, maximum leaf length, and soluble sugars contents of all the Cd-and-submergence-treated plants were more than those of the untreated control. Although Cd inhibits plants growth, decreases chlorophyll and biomass content, and with the submergence induced the leaf and shoot elongation, more part of the Cd-and-submergence stress plants appeared in the air, exhibited fast growth with maintenance of leaf color, which guaranteed the plants' photosynthesis, and ensured the total biomass and carbohydrate sustainability, further promoting Cd-and-submergence tolerance. The results imply that the negative

  11. Submerged in darkness: adaptations to prolonged submergence by woody species of the Amazonian floodplains

    PubMed Central

    Parolin, Pia

    2009-01-01

    Background In Amazonian floodplain forests, >1000 tree species grow in an environment subject to extended annual submergence which can last up to 9 months each year. Water depth can reach 10 m, fully submerging young and also adult trees, most of which reproduce during the flood season. Complete submergence occurs regularly at the seedling or sapling stage for many species that colonize low-lying positions in the flooding gradient. Here hypoxic conditions prevail close to the water surface in moving water, while anaerobic conditions are common in stagnant pools. Light intensities in the floodwater are very low. Questions and Aims Despite a lack of both oxygen and light imposed by submergence for several months, most leafed seedlings survive. Furthermore, underwater growth has also been observed in several species in the field and under experimental conditions. The present article assesses how these remarkable plants react to submergence and discusses physiological mechanisms and anatomical adaptations that may explain their success. PMID:19001429

  12. Looking north at uing press of the submerged arc weld ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Looking north at u-ing press of the submerged arc weld (saw) line of the main pipe mill building, bay 7. - U.S. Steel National Tube Works, Main Pipe Mill Building, Along Monongahela River, McKeesport, Allegheny County, PA

  13. Acoustic and adsorption properties of submerged wood

    NASA Astrophysics Data System (ADS)

    Hilde, Calvin Patrick

    Wood is a common material for the manufacture of many products. Submerged wood, in particular, is used in niche markets, such as the creation of musical instruments. An initial study performed on submerged wood from Ootsa Lake, British Columbia, provided results that showed that the wood was not suitable for musical instruments. This thesis re-examined the submerged wood samples. After allowing the wood to age unabated in a laboratory setting, the wood was retested under the hypothesis that the physical acoustic characteristics would improve. It was shown, however, that the acoustic properties became less adequate after being left to sit. The adsorption properties of the submerged wood were examined to show that the submerged wood had a larger accessible area of wood than that of control wood samples. This implied a lower amount of crystalline area within the submerged wood. From the combined adsorption and acoustic data for the submerged wood, relationships between the moisture content and speed of sound were created and combined with previous research to create a proposed model to describe how the speed of sound varies with temperature, moisture content and the moisture content corresponding to complete hydration of sorption sites within the wood.

  14. Measurement of Submerged Oil/Gas Leaks using ROV Video

    NASA Astrophysics Data System (ADS)

    Shaffer, Franklin; de Vera, Giorgio; Lee, Kenneth; Savas, Ömer

    2013-11-01

    Drilling for oil or gas in the Gulf of Mexico is increasing rapidly at depths up to three miles. The National Commission on the Deepwater Horizon Oil Leak concluded that inaccurate estimates of the leak rate from the Deepwater Horizon caused an inadequate response and attempts to cap the leak to fail. The first response to a submerged oil/gas leak will be to send a Remotely Operated Vehicle (ROV) down to view the leak. During the response to the Deepwater Horizon crisis, the authors Savas and Shaffer were members of the Flow Rate Technical Group's Plume Team who used ROV video to develop the FRTG's first official estimates of the oil leak rate. Savas and Shaffer developed an approach using the larger, faster jet features (e.g., turbulent eddies, vortices, entrained particles) in the near-field developing zone to measure discharge rates. The authors have since used the Berkeley Tow Tank to test this approach on submerged dye-colored water jets and compressed air jets. Image Correlation Velocimetry has been applied to measure the velocity of visible features. Results from tests in the Berkeley Tow Tank and submerged oil jets in the OHMSETT facility will be presented.

  15. Model United Nations and Deep Learning: Theoretical and Professional Learning

    ERIC Educational Resources Information Center

    Engel, Susan; Pallas, Josh; Lambert, Sarah

    2017-01-01

    This article demonstrates that the purposeful subject design, incorporating a Model United Nations (MUN), facilitated deep learning and professional skills attainment in the field of International Relations. Deep learning was promoted in subject design by linking learning objectives to Anderson and Krathwohl's (2001) four levels of knowledge or…

  16. Drought and submergence tolerance in plants

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Du, Hewei; Zhou, Yufan; Oksenberg, Nir

    The invention provides methods of genetically modified plants to increase tolerance to drought and/or submergence. The invention additionally provides plants having increased drought and/or submergence tolerance engineered using such methods.

  17. Current Status of The Romanian National Deep Geological Repository Program

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Radu, M.; Nicolae, R.; Nicolae, D.

    2008-07-01

    Construction of a deep geological repository is a very demanding and costly task. By now, countries that have Candu reactors, have not processed the spent fuel passing to the interim storage as a preliminary step of final disposal within the nuclear fuel cycle back-end. Romania, in comparison to other nations, represents a rather small territory, with high population density, wherein the geological formation areas with radioactive waste storage potential are limited and restricted not only from the point of view of the selection criteria due to the rocks natural characteristics, but also from the point of view of their involvementmore » in social and economical activities. In the framework of the national R and D Programs, series of 'Map investigations' have been made regarding the selection and preliminary characterization of the host geological formation for the nation's spent fuel deep geological repository. The fact that Romania has many deposits of natural gas, oil, ore and geothermal water, and intensively utilizes soil and also is very forested, cause some of the apparent acceptable sites to be rejected in the subsequent analysis. Currently, according to the Law on the spent fuel and radioactive waste management, including disposal, The National Agency of Radioactive Waste is responsible and coordinates the national strategy in the field and, subsequently, further actions will be decided. The Romanian National Strategy, approved in 2004, projects the operation of a deep geological repository to begin in 2055. (authors)« less

  18. Submergible torch for treating waste solutions and method thereof

    DOEpatents

    Mattus, Alfred J.

    1995-01-01

    A submergible torch for removing nitrate and/or nitrite ions from a waste solution containing nitrate and/or nitrite ions comprises: a torch tip, a fuel delivery mechanism, a fuel flow control mechanism, a catalyst, and a combustion chamber. The submergible torch is ignited to form a flame within the combustion chamber of the submergible torch. The torch is submerged in a waste solution containing nitrate and/or nitrite ions in such a manner that the flame is in contact with the waste solution and the catalyst and is maintained submerged for a period of time sufficient to decompose the nitrate and/or nitrite ions present in the waste solution.

  19. Submergible torch for treating waste solutions and method thereof

    DOEpatents

    Mattus, Alfred J.

    1994-01-01

    A submergible torch for removing nitrate and/or nitrite ions from a waste solution containing nitrate and/or nitrite ions comprises: a torch tip, a fuel delivery mechanism, a fuel flow control mechanism, a catalyst, and a combustion chamber. The submergible torch is ignited to form a flame within the combustion chamber of the submergible torch. The torch is submerged in a waste solution containing nitrate and/or nitrite ions in such a manner that the flame is in contact with the waste solution and the catalyst and is maintained submerged for a period of time sufficient to decompose the nitrate and/or nitrite ions present in the waste solution.

  20. On the tsunami wave-submerged breakwater interaction

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Filianoti, P.; Piscopo, R.

    The tsunami wave loads on a submerged rigid breakwater are inertial. It is the result arising from the simple calculation method here proposed, and it is confirmed by the comparison with results obtained by other researchers. The method is based on the estimate of the speed drop of the tsunami wave passing over the breakwater. The calculation is rigorous for a sinusoidal wave interacting with a rigid submerged obstacle, in the framework of the linear wave theory. This new approach gives a useful and simple tool for estimating tsunami loads on submerged breakwaters.An unexpected novelty come out from a workedmore » example: assuming the same wave height, storm waves are more dangerous than tsunami waves, for the safety against sliding of submerged breakwaters.« less

  1. Predicting the Location and Spatial Extent of Submerged Coral Reef Habitat in the Great Barrier Reef World Heritage Area, Australia

    PubMed Central

    Bridge, Tom; Beaman, Robin; Done, Terry; Webster, Jody

    2012-01-01

    Aim Coral reef communities occurring in deeper waters have received little research effort compared to their shallow-water counterparts, and even such basic information as their location and extent are currently unknown throughout most of the world. Using the Great Barrier Reef as a case study, habitat suitability modelling is used to predict the distribution of deep-water coral reef communities on the Great Barrier Reef, Australia. We test the effectiveness of a range of geophysical and environmental variables for predicting the location of deep-water coral reef communities on the Great Barrier Reef. Location Great Barrier Reef, Australia. Methods Maximum entropy modelling is used to identify the spatial extent of two broad communities of habitat-forming megabenthos phototrophs and heterotrophs. Models were generated using combinations of geophysical substrate properties derived from multibeam bathymetry and environmental data derived from Bio-ORACLE, combined with georeferenced occurrence records of mesophotic coral communities from autonomous underwater vehicle, remotely operated vehicle and SCUBA surveys. Model results are used to estimate the total amount of mesophotic coral reef habitat on the GBR. Results Our models predict extensive but previously undocumented coral communities occurring both along the continental shelf-edge of the Great Barrier Reef and also on submerged reefs inside the lagoon. Habitat suitability for phototrophs is highest on submerged reefs along the outer-shelf and the deeper flanks of emergent reefs inside the GBR lagoon, while suitability for heterotrophs is highest in the deep waters along the shelf-edge. Models using only geophysical variables consistently outperformed models incorporating environmental data for both phototrophs and heterotrophs. Main Conclusion Extensive submerged coral reef communities that are currently undocumented are likely to occur throughout the Great Barrier Reef. High-quality bathymetry data can be used

  2. Submergible torch for treating waste solutions and method thereof

    DOEpatents

    Mattus, A.J.

    1994-12-06

    A submergible torch is described for removing nitrate and/or nitrite ions from a waste solution containing nitrate and/or nitrite ions comprises: a torch tip, a fuel delivery mechanism, a fuel flow control mechanism, a catalyst, and a combustion chamber. The submergible torch is ignited to form a flame within the combustion chamber of the submergible torch. The torch is submerged in a waste solution containing nitrate and/or nitrite ions in such a manner that the flame is in contact with the waste solution and the catalyst and is maintained submerged for a period of time sufficient to decompose the nitrate and/or nitrite ions present in the waste solution. 2 figures.

  3. Harvesting microalgal biomass using submerged microfiltration membranes.

    PubMed

    Bilad, M R; Vandamme, D; Foubert, I; Muylaert, K; Vankelecom, Ivo F J

    2012-05-01

    This study was performed to investigate the applicability of submerged microfiltration as a first step of up-concentration for harvesting both a freshwater green algae species Chlorella vulgaris and a marine diatom Phaeodactylum tricornutum using three lab-made membranes with different porosity. The filtration performance was assessed by conducting the improved flux step method (IFM) and batch up-concentration filtrations. The fouling autopsy of the membranes was performed by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) and Fourier transform infrared spectroscopy (FTIR). The cost analysis was estimated based on the data of a related full-scale submerged membrane bioreactor (MBR). Overall results suggest that submerged microfiltration for algal harvesting is economically feasible. The IFM results indicate a low degree of fouling, comparable to the one obtained for a submerged MBR. By combining the submerged microfiltration with centrifugation to reach a final concentration of 22% w/v, the energy consumption to dewater C. vulgaris and P. tricornutum is 0.84 kW h/m(3) and 0.91 kW h/m(3), respectively. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. Fallout plume of submerged oil from Deepwater Horizon

    PubMed Central

    Valentine, David L.; Fisher, G. Burch; Bagby, Sarah C.; Nelson, Robert K.; Reddy, Christopher M.; Sylva, Sean P.; Woo, Mary A.

    2014-01-01

    The sinking of the Deepwater Horizon in the Gulf of Mexico led to uncontrolled emission of oil to the ocean, with an official government estimate of ∼5.0 million barrels released. Among the pressing uncertainties surrounding this event is the fate of ∼2 million barrels of submerged oil thought to have been trapped in deep-ocean intrusion layers at depths of ∼1,000–1,300 m. Here we use chemical distributions of hydrocarbons in >3,000 sediment samples from 534 locations to describe a footprint of oil deposited on the deep-ocean floor. Using a recalcitrant biomarker of crude oil, 17α(H),21β(H)-hopane (hopane), we have identified a 3,200-km2 region around the Macondo Well contaminated by ∼1.8 ± 1.0 × 106 g of excess hopane. Based on spatial, chemical, oceanographic, and mass balance considerations, we calculate that this contamination represents 4–31% of the oil sequestered in the deep ocean. The pattern of contamination points to deep-ocean intrusion layers as the source and is most consistent with dual modes of deposition: a “bathtub ring” formed from an oil-rich layer of water impinging laterally upon the continental slope (at a depth of ∼900–1,300 m) and a higher-flux “fallout plume” where suspended oil particles sank to underlying sediment (at a depth of ∼1,300–1,700 m). We also suggest that a significant quantity of oil was deposited on the ocean floor outside this area but so far has evaded detection because of its heterogeneous spatial distribution. PMID:25349409

  5. Fallout plume of submerged oil from Deepwater Horizon.

    PubMed

    Valentine, David L; Fisher, G Burch; Bagby, Sarah C; Nelson, Robert K; Reddy, Christopher M; Sylva, Sean P; Woo, Mary A

    2014-11-11

    The sinking of the Deepwater Horizon in the Gulf of Mexico led to uncontrolled emission of oil to the ocean, with an official government estimate of ∼ 5.0 million barrels released. Among the pressing uncertainties surrounding this event is the fate of ∼ 2 million barrels of submerged oil thought to have been trapped in deep-ocean intrusion layers at depths of ∼ 1,000-1,300 m. Here we use chemical distributions of hydrocarbons in >3,000 sediment samples from 534 locations to describe a footprint of oil deposited on the deep-ocean floor. Using a recalcitrant biomarker of crude oil, 17α(H),21β(H)-hopane (hopane), we have identified a 3,200-km(2) region around the Macondo Well contaminated by ∼ 1.8 ± 1.0 × 10(6) g of excess hopane. Based on spatial, chemical, oceanographic, and mass balance considerations, we calculate that this contamination represents 4-31% of the oil sequestered in the deep ocean. The pattern of contamination points to deep-ocean intrusion layers as the source and is most consistent with dual modes of deposition: a "bathtub ring" formed from an oil-rich layer of water impinging laterally upon the continental slope (at a depth of ∼ 900-1,300 m) and a higher-flux "fallout plume" where suspended oil particles sank to underlying sediment (at a depth of ∼ 1,300-1,700 m). We also suggest that a significant quantity of oil was deposited on the ocean floor outside this area but so far has evaded detection because of its heterogeneous spatial distribution.

  6. The National Deep-Sea Coral and Sponge Database: A Comprehensive Resource for United States Deep-Sea Coral and Sponge Records

    NASA Astrophysics Data System (ADS)

    Dornback, M.; Hourigan, T.; Etnoyer, P.; McGuinn, R.; Cross, S. L.

    2014-12-01

    Research on deep-sea corals has expanded rapidly over the last two decades, as scientists began to realize their value as long-lived structural components of high biodiversity habitats and archives of environmental information. The NOAA Deep Sea Coral Research and Technology Program's National Database for Deep-Sea Corals and Sponges is a comprehensive resource for georeferenced data on these organisms in U.S. waters. The National Database currently includes more than 220,000 deep-sea coral records representing approximately 880 unique species. Database records from museum archives, commercial and scientific bycatch, and from journal publications provide baseline information with relatively coarse spatial resolution dating back as far as 1842. These data are complemented by modern, in-situ submersible observations with high spatial resolution, from surveys conducted by NOAA and NOAA partners. Management of high volumes of modern high-resolution observational data can be challenging. NOAA is working with our data partners to incorporate this occurrence data into the National Database, along with images and associated information related to geoposition, time, biology, taxonomy, environment, provenance, and accuracy. NOAA is also working to link associated datasets collected by our program's research, to properly archive them to the NOAA National Data Centers, to build a robust metadata record, and to establish a standard protocol to simplify the process. Access to the National Database is provided through an online mapping portal. The map displays point based records from the database. Records can be refined by taxon, region, time, and depth. The queries and extent used to view the map can also be used to download subsets of the database. The database, map, and website is already in use by NOAA, regional fishery management councils, and regional ocean planning bodies, but we envision it as a model that can expand to accommodate data on a global scale.

  7. Gap Analysis of Benthic Mapping at Three National Parks: Assateague Island National Seashore, Channel Islands National Park, and Sleeping Bear Dunes National Lakeshore

    USGS Publications Warehouse

    Rose, Kathryn V.; Nayegandhi, Amar; Moses, Christopher S.; Beavers, Rebecca; Lavoie, Dawn; Brock, John C.

    2012-01-01

    The National Park Service (NPS) Inventory and Monitoring (I&M) Program initiated a benthic habitat mapping program in ocean and coastal parks in 2008-2009 in alignment with the NPS Ocean Park Stewardship 2007-2008 Action Plan. With more than 80 ocean and Great Lakes parks encompassing approximately 2.5 million acres of submerged territory and approximately 12,000 miles of coastline (Curdts, 2011), this Servicewide Benthic Mapping Program (SBMP) is essential. This report presents an initial gap analysis of three pilot parks under the SBMP: Assateague Island National Seashore (ASIS), Channel Islands National Park (CHIS), and Sleeping Bear Dunes National Lakeshore (SLBE) (fig. 1). The recommended SBMP protocols include servicewide standards (for example, gap analysis, minimum accuracy, final products) as well as standards that can be adapted to fit network and park unit needs (for example, minimum mapping unit, mapping priorities). The SBMP requires the inventory and mapping of critical components of coastal and marine ecosystems: bathymetry, geoforms, surface geology, and biotic cover. In order for a park unit benthic inventory to be considered complete, maps of bathymetry and other key components must be combined into a final report (Moses and others, 2010). By this standard, none of the three pilot parks are mapped (inventoried) to completion with respect to submerged resources. After compiling the existing benthic datasets for these parks, this report has concluded that CHIS, with 49 percent of its submerged area mapped, has the most complete benthic inventory of the three. The ASIS submerged inventory is 41 percent complete, and SLBE is 17.5 percent complete.

  8. Patterns of peroxidative ethane emission from submerged rice seedlings indicate that damage from reactive oxygen species takes place during submergence and is not necessarily a post-anoxic phenomenon.

    PubMed

    Santosa, I E; Ram, P C; Boamfa, E I; Laarhoven, L J J; Reuss, J; Jackson, M B; Harren, F J M

    2007-06-01

    Using ethane as a marker for peroxidative damage to membranes by reactive oxygen species (ROS) we examined the injury of rice seedlings during submergence in the dark. It is often expressed that membrane injury from ROS is a post-submergence phenomenon occurring when oxygen is re-introduced after submergence-induced anoxia. We found that ethane production, from rice seedlings submerged for 24-72 h, was stimulated to 4-37 nl gFW(-1), indicating underwater membrane peroxidation. When examined a week later the seedlings were damaged or had died. On de-submergence in air, ethane production rates rose sharply, but fell back to less than 0.1 nl gFW(-1) h(-1) after 2 h. We compared submergence-susceptible and submergence-tolerant cultivars, submergence starting in the morning (more damage) and in the afternoon (less damage) and investigated different submergence durations. The seedlings showed extensive fatality whenever total ethane emission exceeded about 15 nl gFW(-1). Smaller amounts of ethane emission were linked to less extensive injury to leaves. Partial oxygen shortage (O(2) levels <1%) imposed for 2 h in gas phase mixtures also stimulated ethane production. In contrast, seedlings under anaerobic gas phase conditions produced no ethane until re-aerated: then a small peak was observed followed by a low, steady ethane production. We conclude that damage during submergence is not associated with extensive anoxia. Instead, injury is linked to membrane peroxidation in seedlings that are partially oxygen deficient while submerged. On return to air, further peroxidation is suppressed within about 2 h indicating effective control of ROS production not evident during submergence itself.

  9. Preliminary Analysis of a Submerged Wave Energy Device

    NASA Astrophysics Data System (ADS)

    Wagner, J. R.; Wagner, J. J.; Hayatdavoodi, M.; Ertekin, R. C.

    2016-02-01

    Preliminary analysis of a submerged wave energy harvesting device is presented. The device is composed of a thin, horizontally submerged plate that is restricted to heave oscillations under the influence of surface waves. The submerged plate is oscillating, and it can be attached to a fixed rotor, or a piston, to harvest the wave energy. A fully submerged wave energy converter is preferred over a surface energy convertor due to its durability and less visual and physical distractions it presents. In this study, the device is subject to nonlinear shallow-water waves. Wave loads on the submerged oscillating plate are obtained via the Level I Green-Naghdi equations. The unsteady motion of the plate is obtained by solving the nonlinear equations of motion. The results are obtained for a range of waves with varying heights and periods. The amplitude and period of plate oscillations are analyzed as functions of the wave parameters and plate width. Particular attention is given to the selection of the site of desired wave field. Initial estimation on the amount of energy extraction from the device, located near shore at a given site, is provided.

  10. A perspective on underwater photosynthesis in submerged terrestrial wetland plants

    PubMed Central

    Colmer, Timothy D.; Winkel, Anders; Pedersen, Ole

    2011-01-01

    Background and aims Wetland plants inhabit flood-prone areas and therefore can experience episodes of complete submergence. Submergence impedes exchange of O2 and CO2 between leaves and the environment, and light availability is also reduced. The present review examines limitations to underwater net photosynthesis (PN) by terrestrial (i.e. usually emergent) wetland plants, as compared with submerged aquatic plants, with focus on leaf traits for enhanced CO2 acquisition. Scope Floodwaters are variable in dissolved O2, CO2, light and temperature, and these parameters influence underwater PN and the growth and survival of submerged plants. Aquatic species possess morphological and anatomical leaf traits that reduce diffusion limitations to CO2 uptake and thus aid PN under water. Many aquatic plants also have carbon-concentrating mechanisms to increase CO2 at Rubisco. Terrestrial wetland plants generally lack the numerous beneficial leaf traits possessed by aquatic plants, so submergence markedly reduces PN. Some terrestrial species, however, produce new leaves with a thinner cuticle and higher specific leaf area, whereas others have leaves with hydrophobic surfaces so that gas films are retained when submerged; both improve CO2 entry. Conclusions Submergence inhibits PN by terrestrial wetland plants, but less so in species that produce new leaves under water or in those with leaf gas films. Leaves with a thinner cuticle, or those with gas films, have improved gas diffusion with floodwaters, so that underwater PN is enhanced. Underwater PN provides sugars and O2 to submerged plants. Floodwaters often contain dissolved CO2 above levels in equilibrium with air, enabling at least some PN by terrestrial species when submerged, although rates remain well below those in air. PMID:22476500

  11. [Algal control ability of allelopathically active submerged macrophytes: a review].

    PubMed

    Xiao, Xi; Lou, Li-ping; Li, Hua; Chen, Ying-xu

    2009-03-01

    The inhibitory effect of allelochemicals released by submerged macrophytes on phytoplankton is considered as one of the mechanisms that contribute to the stabilization of clear-water status in shallow lakes. This paper reviewed the research progress in the allelopathy of submerged macrophytes on algae from the aspects of the occurrence frequency and coverage of allelopathically active submerged macrophytes in lakes, and the kinds and allelopathical effects of the allelochemicals released from the macrophytes. The previous researches indicated that allelopathically active submerged macrophyte species such as Myriophyllum, Ceratophyllum, and Elodea were efficient to control phytoplankton, especially when their biomass was high enough, and the dominant algae were sensitive species. The allelochemicals such as hydroxybenzene released by the submerged macrophytes could inhibit the growth of algae. Different phytoplankton species exhibited different sensitivity against allelochemicals, e.g., cyanobacteria and diatom were more sensitive than green algae, while epiphytic species were less sensitive than phytoplankton. Environmental factors such as light, temperature, and nutrients could significantly affect the allelopathical effect of submerged macrophytes. The research of the allelopathy of submerged macrophytes is still at its beginning, and further researches are needed on the effects of environmental factors on the allelopathy, extraction and identification of allelochemicals, selective algal control mechanisms, and metabolism of the allelochmicals.

  12. Energy configuration optimization of submerged propeller in oxidation ditch based on CFD

    NASA Astrophysics Data System (ADS)

    Wu, S. Y.; Zhou, D. Q.; Zheng, Y.

    2012-11-01

    The submerged propeller is presented as an important dynamic source in oxidation ditch. In order to guarantee the activated sludge not deposit, it is necessary to own adequate drive power. Otherwise, it will cause many problems such as the awful mixed flow and the great consuming of energy. At present, carrying on the installation optimization of submerged propeller in oxidation ditch mostly depends on experience. So it is necessary to use modern design method to optimize the installation position and number of submerged propeller, and to research submerged propeller flow field characteristics. The submerged propeller internal flow is simulated by using CFD software FLUENT6.3. Based on Navier-Stokes equations and standard k - ɛ turbulence model, the flow was simulated by using a SIMPLE algorithm. The results indicate that the submerged propeller installation position change could avoid the condition of back mixing, which caused by the strong drive. Besides, the problem of sludge deposit and the low velocity in the bend which caused by the drive power attenuation could be solved. By adjusting the submerged propeller number, the least power density that the mixing drive needed could be determined and saving energy purpose could be achieved. The study can provide theoretical guidance for optimize the submerged propeller installation position and determine submerged propeller number.

  13. [Deep continuous palliative sedation in the Opinion adopted by the Italian National Bioethics Committee (Deep palliative sedation)].

    PubMed

    Cembrani, Fabio

    2016-01-01

    The Author examines the recent opinion delivered by the Italian National Committee for Bioethics on deep palliative sedation. In particular, it examines its strengths and ample shade that show its ideology, once again, in contrast with the right of every human being to die with dignity.

  14. 49 CFR 193.2629 - External corrosion control: buried or submerged components.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false External corrosion control: buried or submerged... corrosion control: buried or submerged components. (a) Each buried or submerged component that is subject to external corrosive attack must be protected from external corrosion by— (1) Material that has been designed...

  15. 49 CFR 193.2629 - External corrosion control: buried or submerged components.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false External corrosion control: buried or submerged... corrosion control: buried or submerged components. (a) Each buried or submerged component that is subject to external corrosive attack must be protected from external corrosion by— (1) Material that has been designed...

  16. 49 CFR 193.2629 - External corrosion control: buried or submerged components.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false External corrosion control: buried or submerged... corrosion control: buried or submerged components. (a) Each buried or submerged component that is subject to external corrosive attack must be protected from external corrosion by— (1) Material that has been designed...

  17. 49 CFR 193.2629 - External corrosion control: buried or submerged components.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false External corrosion control: buried or submerged... corrosion control: buried or submerged components. (a) Each buried or submerged component that is subject to external corrosive attack must be protected from external corrosion by— (1) Material that has been designed...

  18. Submerged cultivation of medicinal mushrooms: bioprocesses and products (review).

    PubMed

    Elisashvili, Vladimir

    2012-01-01

    Medicinal mushrooms belonging to higher Basidiomycetes are an immensely rich yet largely untapped resource of useful, easily accessible, natural compounds with various biological activities that may promote human well-being. The medicinal properties are found in various cellular components and secondary metabolites (polysaccharides, proteins and their complexes, phenolic compounds, polyketides, triterpenoids, steroids, alkaloids, nucleotides, etc.), which have been isolated and identified from the fruiting bodies, culture mycelium, and culture broth of mushrooms. Some of these compounds have cholesterol-lowering, anti-diabetic, antioxidant, antitumor, immunomodulating, antimicrobial, and antiviral activities ready for industrial trials and further commercialization, while others are in various stages of development. Recently, the submerged cultivation of medicinal mushrooms has received a great deal of attention as a promising and reproducible alternative for the efficient production of mushroom mycelium and metabolites. Submerged cultivation of mushrooms has significant industrial potential, but its success on a commercial scale depends on increasing product yields and development of novel production systems that address the problems associated with this technique of mushroom cultivation. In spite of many researchers' efforts for the production of bioactive metabolites by mushrooms, the physiological and engineering aspects of submerged cultures are still far from being thoroughly studied. The vast majority of studies have focused on polysaccharide and ganoderic acid production in submerged cultivation of medicinal mushrooms, and very little has been written so far on the antioxidant and hemagglutinating activity of submerged mushroom cultures. The purpose of this review is to provide an update of the present state of the art and future prospects of submerged cultivation of medicinal mushrooms to produce mycelium and bioactive metabolites, and to make a

  19. Forced convection in vertical Bridgman configuration with the submerged heater

    NASA Astrophysics Data System (ADS)

    Meyer, S.; Ostrogorsky, A. G.

    1997-02-01

    Ga-doped Ge single crystals were grown in vertical Bridgman configuration, using the submerged heater method (SHM). When used without rotation, the submerged heater drastically reduces convection at the solid-liquid interface. When the submerged heater is set in to rotation or oscillatory rotation, it acts as a centrifugal viscous pump, inducing forced convection (radial-inward flow) along the interface. The flow produced by a rotation and oscillatory rotation of the submerged heater was visualized using a 1 : 1 scale model. The vigorous mixing produced by the oscillatory rotation creates a nearly perfectly stirred melt, and yields a uniform lateral distribution of the dopant. The crystals were free of unintentionally produced striae.

  20. Propulsive Efficiencies of Magnetohydrodynamic Submerged Vehicular Propulsors

    DTIC Science & Technology

    1990-04-01

    TERMS (Con’we on mrae . neoaay and kWerty by back nLt.) FIELD GROUP SUB-GROUP Magnetohydrodynamic propulsion, marine propulsion, seawater pump ...propelling a vehicular structure by a seawater elec- tromagnetic pump . This propulsion system can be applied to a surface ship or a submerged vehicle; however...structure by a seawater electromagnetic pump . This propulsion system can be applied to a surface ship or a submerged vehicle; however, in this work only

  1. Contrasting Changes Caused by Drought and Submergence Stresses in Bermudagrass (Cynodon dactylon)

    PubMed Central

    Ye, Tiantian; Shi, Haitao; Wang, Yanping; Chan, Zhulong

    2015-01-01

    In this study, we investigated the mechanisms by which bermudagrass withstands the drought and submergence stresses through physiological, proteomic and metabolomic approaches. The results showed that significant physiological changes were observed after drought treatment, while only slight changes after submergence treatment, including compatible solute contents, ROS levels and antioxidant enzyme activities. Proteomics results showed that 81 proteins regulated by drought or submergence treatment were identified by MALDI-TOF-MS. Among them, 76 proteins were modulated by drought stress with 46 increased abundance and 30 decreased abundance. Forty-five showed abundance changes after submergence treatment with 10 increased and 35 decreased. Pathway enrichment analysis revealed that pathways of amino acid metabolism and mitochondrial electron transport/ATP synthesis were only enriched by drought treatment, while other pathways including photosynthesis, biodegradation of xenobiotics, oxidative pentose phosphate, glycolysis and redox were commonly over-represented after both drought and submergence treatments. Metabolomic analysis indicated that most of the metabolites were up-regulated by drought stress, while 34 of 40 metabolites contents exhibited down-regulation or no significant changes when exposed to submergence stress, including sugars and sugar alcohols. These data indicated that drought stress extensively promoted photosynthesis and redox metabolisms while submergence stress caused declined metabolisms and dormancy in Cynodon dactylon. Taken together, the quiescence strategy with retarded growth might allow bermudagrass to be adaptive to long-term submerged environment, while activation of photosynthesis and redox, and accumulation of compatible solutes and molecular chaperones increased bermudagrass tolerance to drought stress. PMID:26617615

  2. Submergible barge retrievable storage and permanent disposal system for radioactive waste

    DOEpatents

    Goldsberry, Fred L.; Cawley, William E.

    1981-01-01

    A submergible barge and process for submerging and storing radioactive waste material along a seabed. A submergible barge receives individual packages of radwaste within segregated cells. The cells are formed integrally within the barge, preferably surrounded by reinforced concrete. The cells are individually sealed by a concrete decking and by concrete hatch covers. Seawater may be vented into the cells for cooling, through an integral vent arrangement. The vent ducts may be attached to pumps when the barge is bouyant. The ducts are also arranged to promote passive ventilation of the cells when the barge is submerged. Packages of the radwaste are loaded into individual cells within the barge. The cells are then sealed and the barge is towed to the designated disposal-storage site. There, the individual cells are flooded and the barge will begin descent controlled by a powered submarine control device to the seabed storage site. The submerged barge will rest on the seabed permanently or until recovered by a submarine control device.

  3. Deep-sea genetic resources: New frontiers for science and stewardship in areas beyond national jurisdiction

    NASA Astrophysics Data System (ADS)

    Harden-Davies, Harriet

    2017-03-01

    The deep-sea is a large source of marine genetic resources (MGR), which have many potential uses and are a growing area of research. Much of the deep-sea lies in areas beyond national jurisdiction (ABNJ), including 65% of the global ocean. MGR in ABNJ occupy a significant gap in the international legal framework. Access and benefit sharing of MGR is a key issue in the development of a new international legally-binding instrument under the United Nations Convention on the Law of the Sea (UNCLOS) for the conservation and sustainable use of marine biological diversity in ABNJ. This paper examines how this is relevant to deep-sea scientific research and identifies emerging challenges and opportunities. There is no internationally agreed definition of MGR, however, deep-sea genetic resources could incorporate any biological material including genes, proteins and natural products. Deep-sea scientific research is the key actor accessing MGR in ABNJ and sharing benefits such as data, samples and knowledge. UNCLOS provides the international legal framework for marine scientific research, international science cooperation, capacity building and marine technology transfer. Enhanced implementation could support access and benefit sharing of MGR in ABNJ. Deep-sea scientific researchers could play an important role in informing practical new governance solutions for access and benefit sharing of MGR that promote scientific research in ABNJ and support deep-sea stewardship. Advancing knowledge of deep-sea biodiversity in ABNJ, enhancing open-access to data and samples, standardisation and international marine science cooperation are significant potential opportunity areas.

  4. An Analysis of Explosion-Induced Bending Damage in Submerged Shell Targets,

    DTIC Science & Technology

    1984-12-01

    AD-R169 009 AN ANRLYSIS OF EXPLOSION-INDUCED SENDING DfIMAhE IN SUBMERGED SHELL TRRGETS(U) NRVRL SURFACE HERPONS CENTER OANLOREN YR N NOUSSOUROS DEC...BENDING DAMAGE IN SUBMERGED SHELL TARGETS 0 o BY MINOS MOUSSOUROS RESEARCH AND TECHNOLOGY DEPARTMENT < DECEMBER 1984 Aptroved f u, blic release...IN SUBMERGED ) SHELL TARGETS 6. PERFORMING ORG. REPORT NUMBER 7 AUTHOR(&) S. CONTRACT OR GRANT NUMERI(s) jMlNoS MOUSSoUROS 9 PERFORMING

  5. Canopy Modeling of Aquatic Vegetation: Construction of Submerged Vegetation Index

    NASA Astrophysics Data System (ADS)

    Ma, Z.; Zhou, G.

    2018-04-01

    The unique spectral characteristics of submerged vegetation in wetlands determine that the conventional terrestrial vegetation index cannot be directly employed to species identification and parameter inversion of submerged vegetation. Based on the Aquatic Vegetation Radiative Transfer model (AVRT), this paper attempts to construct an index suitable for submerged vegetation, the model simulated data and a scene of Sentinel-2A image in Taihu Lake, China are utilized for assessing the performance of the newly constructed indices and the existent vegetation indices. The results show that the angle index composed by 525 nm, 555 nm and 670 nm can resist the effects of water columns and is more sensitive to vegetation parameters such as LAI. Furthermore, it makes a well discrimination between submerged vegetation and water bodies in the satellite data. We hope that the new index will provide a theoretical basis for future research.

  6. Development of a ROV Deployed Video Analysis Tool for Rapid Measurement of Submerged Oil/Gas Leaks

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Savas, Omer

    Expanded deep sea drilling around the globe makes it necessary to have readily available tools to quickly and accurately measure discharge rates from accidental submerged oil/gas leak jets for the first responders to deploy adequate resources for containment. We have developed and tested a field deployable video analysis software package which is able to provide in the field sufficiently accurate flow rate estimates for initial responders in accidental oil discharges in submarine operations. The essence of our approach is based on tracking coherent features at the interface in the near field of immiscible turbulent jets. The software package, UCB_Plume, ismore » ready to be used by the first responders for field implementation. We have tested the tool on submerged water and oil jets which are made visible using fluorescent dyes. We have been able to estimate the discharge rate within 20% accuracy. A high end WINDOWS laptop computer is suggested as the operating platform and a USB connected high speed, high resolution monochrome camera as the imaging device are sufficient for acquiring flow images under continuous unidirectional illumination and running the software in the field. Results are obtained over a matter of minutes.« less

  7. Remote sensing of submerged aquatic vegetation in lower Chesapeake Bay - A comparison of Landsat MSS to TM imagery

    NASA Technical Reports Server (NTRS)

    Ackleson, S. G.; Klemas, V.

    1987-01-01

    Landsat MSS and TM imagery, obtained simultaneously over Guinea Marsh, VA, as analyzed and compares for its ability to detect submerged aquatic vegetation (SAV). An unsupervised clustering algorithm was applied to each image, where the input classification parameters are defined as functions of apparent sensor noise. Class confidence and accuracy were computed for all water areas by comparing the classified images, pixel-by-pixel, to rasterized SAV distributions derived from color aerial photography. To illustrate the effect of water depth on classification error, areas of depth greater than 1.9 m were masked, and class confidence and accuracy recalculated. A single-scattering radiative-transfer model is used to illustrate how percent canopy cover and water depth affect the volume reflectance from a water column containing SAV. For a submerged canopy that is morphologically and optically similar to Zostera marina inhabiting Lower Chesapeake Bay, dense canopies may be isolated by masking optically deep water. For less dense canopies, the effect of increasing water depth is to increase the apparent percent crown cover, which may result in classification error.

  8. The Study on the Durability of Submerged Structure Displacement due to Concrete Failure

    NASA Astrophysics Data System (ADS)

    Mohd, M.; Zainon, O.; Rasib, A. W.; Majid, Z.

    2016-09-01

    Concrete structures that exposed to marine environments are subjected to multiple deterioration mechanisms. An overview of the existing technology for submerged concrete, pressure resistant, concrete structures which related such as cracks, debonds, and delamination are discussed. Basic knowledge related to drowning durability such as submerged concrete structures in the maritime environment are the durability of a concrete and the ability to resist to weathering, chemical attack, abrasion or other deterioration processes. The measuring techniques and instrumentation for geometrical monitoring of submerged structural displacements have traditionally been categorized into two groups according to the two main groups, namely as geodetic surveying and geotechnical structural measurements of local displacements. This paper aims to study the durability of submerged concrete displacement and harmful effects of submerged concrete structures.

  9. Submerged plant’s ability to present photosynthesis based on oxygen production

    NASA Astrophysics Data System (ADS)

    Supriatno, B.; Ulfa, K.

    2018-05-01

    This study aims to provide information about alternative experimental photosynthesis for experimental teaching practices in school in the coastal region. The research method was conducted experimentally by taking examples of Submerged plant in littoral area of Leuweng Sancang beach, Garut. Plant samples were given the same light intensity treatment, then the oxygen productivity was studied as an indicator of photosynthesis rate. The results showed that there were different photosynthetic rates in different types of submerged plants. Algae as submerged plants generally photosynthesize at high light intensity. However, there are also plants with photosynthesis in low light. The comparison between sea grass (Thallasia sp) with sea weed (Ulva sp) shows the difference in oxygen productivity. Submerged plants based on their ability to produce measurable oxygen can be utilized for experiments on photosynthesis learning.

  10. Detecting submerged bodies: controlled research using side-scan sonar to detect submerged proxy cadavers.

    PubMed

    Healy, Carrie A; Schultz, John J; Parker, Kenneth; Lowers, Bim

    2015-05-01

    Forensic investigators routinely deploy side-scan sonar for submerged body searches. This study adds to the limited body of literature by undertaking a controlled project to understand how variables affect detection of submerged bodies using side-scan sonar. Research consisted of two phases using small and medium-sized pig (Sus scrofa) carcasses as proxies for human bodies to investigate the effects of terrain, body size, frequency, swath width, and state of decomposition. Results demonstrated that a clear, flat, sandy pond floor terrain was optimal for detection of the target as irregular terrain and/or vegetation are major limitations that can obscure the target. A higher frequency towfish was preferred for small bodies, and a 20 m swath width allowed greater visibility and easier maneuverability of the boat in this environment. Also, the medium-sized carcasses were discernable throughout the 81-day study period, indicating that it is possible to detect bodies undergoing decomposition with side-scan sonar. © 2015 American Academy of Forensic Sciences.

  11. Ethylene-promoted elongation: an adaptation to submergence stress.

    PubMed

    Jackson, Michael B

    2008-01-01

    A sizeable minority of taxa is successful in areas prone to submergence. Many such plants elongate with increased vigour when underwater. This helps to restore contact with the aerial environment by shortening the duration of inundation. Poorly adapted species are usually incapable of this underwater escape. Evidence implicating ethylene as the principal factor initiating fast underwater elongation by leaves or stems is evaluated comprehensively along with its interactions with other hormones and gases. These interactions make up a sequence of events that link the perception of submergence to a prompt acceleration of extension. The review encompasses whole plant physiology, cell biology and molecular genetics. It includes assessments of how submergence threatens plant life and of the extent to which the submergence escape demonstrably improves the likelihood of survival. Experimental testing over many years establishes ethylene-promoted underwater extension as one of the most convincing examples of hormone-mediated stress adaptation by plants. The research has utilized a wide range of species that includes numerous angiosperms, a fern and a liverwort. It has also benefited from detailed physiological and molecular studies of underwater elongation by rice (Oryza sativa) and the marsh dock (Rumex palustris). Despite complexities and interactions, the work reveals that the signal transduction pathway is initiated by the simple expediency of physical entrapment of ethylene within growing cells by a covering of water.

  12. Impacts of climate change on submerged and emergent wetland plants

    Treesearch

    Frederick T. Short; Sarian Kosten; Pamela A. Morgan; Sparkle L Malone; Gregg E. Moore

    2016-01-01

    Submerged and emergent wetland plant communities are evaluated for their response to global climate change (GCC), focusing on seagrasses, submerged freshwater plants, tidal marsh plants, freshwater marsh plants and mangroves. Similarities and differences are assessed in plant community responses to temperature increase, CO2increase, greater UV-B exposure, sea...

  13. Oxygen absorption by adventitious roots promotes the survival of completely submerged terrestrial plants

    PubMed Central

    Ayi, Qiaoli; Zeng, Bo; Liu, Jianhui; Li, Siqi; van Bodegom, Peter M.; Cornelissen, Johannes H. C.

    2016-01-01

    Background and Aims Flooding imposes stress upon terrestrial plants because it results in oxygen deficiency, which is considered a major problem for submerged plants. A common response of terrestrial plants to flooding is the formation of aquatic adventitious roots. Some studies have shown that adventitious roots on submerged plants are capable of absorbing water and nutrients. However, there is no experimental evidence for the possible oxygen uptake function of adventitious roots or for how important this function might be for the survival of plants during prolonged submergence. This study aims to investigate whether adventitious roots absorb oxygen from the water column, and whether this new function is beneficial to the survival of completely submerged plants. Methods Taking Alternanthera philoxeroides (Mart.) Griseb. as a representative species, the profiling of the underwater oxygen gradient towards living and dead adventitious roots on completely submerged plants was conducted, the oxygen concentration in stem nodes with and without adventitious roots was measured, and the growth, survival and non-structural carbohydrate content of completely submerged plants with and without adventitious roots was investigated. Key Results Oxygen profiles in the water column of adventitious roots showed that adventitious roots absorbed oxygen from water. It is found that the oxygen concentration in stem nodes having adventitious roots was higher than that in stem nodes without adventitious roots, which implies that the oxygen absorbed by adventitious roots from water was subsequently transported from the roots to other plant tissues. Compared with plants whose adventitious roots had been pruned, those with intact adventitious roots had slower leaf shedding, slower plant mass reduction, more efficient carbohydrate economy and prolonged survival when completely submerged. Conclusions The adventitious roots of A. philoxeroides formed upon submergence can absorb oxygen from

  14. Demonstration and Field Evaluation of Streambank Stabilization with Submerged Vanes

    USGS Publications Warehouse

    Whitman, H.; Hoopes, J.; Poggi, D.; Fitzpatrick, F.; Walz, K.; ,

    2001-01-01

    The effectiveness of submerged vanes for reducing bank erosion and improving aquatic habitat is being evaluated at a site on North Fish Creek, a Lake Superior tributary. Increased runoff from agricultural areas with clayey soils has increased flood magnitudes and the erosion potential/transport capacity of the stream. Most of the creek's sediment load originates from the erosion of 17 large bluffs. This creek contains important recreational fisheries that are potentially limited by the loss of aquatic habitat from deposition of sediment on spawning beds. Submerged vanes are a cost effective and environmentally less intrusive alternative to traditional structural stabilization measures. Submerged vanes protrude from a channel bed, are oriented at an angle to the local velocity, and are distributed along a portion of channel. They induce a transverse force and torque on the flow along with longitudinal vortexes that alter the cross sectional shape and alignment of the channel. Submerged vanes were installed at a bluff/bend site in summer and fall 2000. The number, size, and layout of the vanes were based upon the channel morphology under estimated bankfull conditions. The effectiveness of the vanes will be evaluated by comparing surveys of the bluff face, streamflow, and channel conditions for several years after installation of the submerged vanes with surveys before and immediately after their installation.

  15. Breaking Wave Impact on a Partially Submerged Rigid Cube in Deep Water

    NASA Astrophysics Data System (ADS)

    Ikeda, C. M.; Choquette, M.; Duncan, J. H.

    2011-11-01

    The impact of a plunging breaking wave on a partially submerged cube is studied experimentally. The experiments are performed in a wave tank that is 14.8 m long, 1.15 m wide and 2.2 m high with a water depth of 0.91 m. A single repeatable plunging breaker is generated from a dispersively focused wave packet (average frequency of 1.4 Hz) that is created with a programmable wave maker. The rigid (L = 30 . 5 cm) cube is centered in the width of the tank and mounted from above with one face oriented normal to the oncoming wave. The position of the center of the front face of the cube is varied from the breaker location (xb ~ 6 . 35 m) to xb + 0 . 05 m in the streamwise direction and from - 0 . 25 L to 0 . 25 L vertically relative to the mean water level. A high-speed digital camera is used to record both white-light and laser-induced fluorescence (LIF) movies of the free surface shape in front of the cube before and after the wave impact. When the wave hits the cube just as the plunging jet is formed, a high-velocity vertical jet is created and the trajectory and maximum height of the jet are strongly influenced by the vertical position of the cube. Supported by the Office of Naval Research, Contract Monitor R. D. Joslin.

  16. The gas jet behavior in submerged Laval nozzle flow

    NASA Astrophysics Data System (ADS)

    Gong, Zhao-xin; Lu, Chuan-jing; Li, Jie; Cao, Jia-yi

    2017-12-01

    The behavior of the combustion gas jet in a Laval nozzle flow is studied by numerical simulations. The Laval nozzle is installed in an engine and the combustion gas comes out of the engine through the nozzle and then injects into the surrounding environment. First, the jet injection into the air is simulated and the results are verified by the theoretical solutions of the 1-D isentropic flow. Then the behavior of the gas jet in a submerged Laval nozzle flow is simulated for various water depths. The stability of the jet and the jet evolution with a series of expansion waves and compression waves are analyzed, as well as the mechanism of the jet in a deep water depth. Finally, the numerical results are compared with existing experimental data and it is shown that the characteristics of the water blockage and the average values of the engine thrust are in good agreement and the unfixed engine in the experiment is the cause of the differences of the frequency and the amplitude of the oscillation.

  17. Production and processing of Metarhizium anisopliae var. acridum submerged conidia for locust and grasshopper control.

    PubMed

    Kassa, Adane; Stephan, Dietrich; Vidal, Stefan; Zimmermann, Gisbert

    2004-01-01

    Currently, mycopesticide development for locust and grasshopper control depends on aerial conidia or submerged spores of entomopathogenic fungi. In our study, the production of submerged conidia of Metarhizium anisopliae var. acridum (IMI 330189) was investigated in a liquid medium containing 3% biomalt and 1% yeast extract (BH-medium). The effects of freeze and spray drying techniques on the quality of submerged conidia were determined. The influence of different additives on the viability of fresh submerged conidia and their suitability for oil flowable concentrate formulation development was assessed. In a BH medium maintained at 180 rev min(-1), at 30 degrees C for 72 h, IMI 330189 produced a green pigmented biomass of submerged conidia whereas in Adámek medium it produced a yellowish biomass of submerged spores. The spore concentration was high in both media; however, the size of the spores produced in the BH medium was significantly lower than those produced in Adámek medium (P < 0.001). Submerged conidia can be effectively dried using either freeze or spray drying techniques. The viability and speed of germination were significantly affected by the drying and pulverizing process (P < 0.001). The initial viability was significantly higher for spray-dried submerged conidia than for freeze-dried spores. Pulverizing of freeze-dried submerged conidia reduced the speed of germination and the viability by 63-95%. Dried submerged conidia can be stored over 45 wk at low temperatures (< 10 degrees) without suffering a significant loss in viability. Furthermore, we have identified carriers that are suitable for oil flowable concentrate formulation development.

  18. Postcolonial partnerships: deep sea research, media coverage and (inter)national narratives on the Galathea Deep Sea Expedition from 1950 to 1952.

    PubMed

    Nielsen, Kristian Hvidtfelt

    2010-03-01

    The Danish Galathea Deep Sea Expedition between 1950 and 1952 combined scientific and official objectives with the production of national and international narratives distributed through the daily press and other media. Dispatched by the Danish government on a newly acquired naval ship, the expedition undertook groundbreaking deep sea research while also devoting efforts to showing the flag, public communication of science, and international cooperation. The expedition was conceived after the war as a way in which to rehabilitate Denmark's reputation internationally and to rebuild national pride. To this end, the expedition included an onboard press section reporting the expedition to the Danish public and to an international audience. The press section mediated the favourable, post-war and postcolonial image of Denmark as an internationalist, scientific, modernizing and civilizing nation for which the expedition planners and many others were hoping. The expedition, therefore, was highly relevant to, indeed fed on, the emerging internationalist agenda in Denmark's foreign policy. Bringing out these aspects of the historical context of the expedition, this paper adds important perspectives to our knowledge about the expedition in particular and, more generally, about scientific exploration in the immediate post-war and postcolonial period.

  19. Submerged passively-safe power plant

    DOEpatents

    Herring, J. Stephen

    1993-01-01

    The invention as presented consists of a submerged passively-safe power station including a pressurized water reactor capable of generating at least 600 MW of electricity, encased in a double hull vessel, and provides fresh water by using the spent thermal energy in a multistage flash desalination process.

  20. Short-term complete submergence of rice at the tillering stage increases yield.

    PubMed

    Zhang, Yajie; Wang, Zhensheng; Li, Lei; Zhou, Qun; Xiao, Yao; Wei, Xing; Zhou, Mingyao

    2015-01-01

    Flooding is a major threat to agricultural production. Most studies have focused on the lower water storage limit in rice fields, whereas few studies have examined the upper water storage limit. This study aimed to explore the effect of waterlogging at the rice tillering stage on rice growth and yield. The early-ripening late japonica variety Yangjing 4227 was selected for this study. The treatments included different submergence depths (submergence depth/plant height: 1/2 (waist submergence), 2/3 (neck submergence), and 1/1 (complete submergence)) and durations (1, 3, and 5 d). The control group was treated with the conventional alternation of drying and wetting. The effects of waterlogging at the tillering stage on root characteristics, dry matter production, nitrogen and phosphorus accumulation, yield, yield components, and 1-aminocyclopropane-1-carboxylic acid synthase (ACS) gene expression were explored. Compared with the control group, the 1/1 group showed significant increases in yield, seed-setting rate, photosynthetically efficient leaf area, and OS-ACS3 gene expression after 1 d of submergence. The grain number per panicle, dry weight of the aboveground and belowground parts, and number of adventitious roots also increased. Correlation analysis revealed a significant positive correlation between the panicle number and nitrogen content; however, no significant correlation was found for phosphorus content. If a decrease in rice yield of less than 10% is acceptable, half, 2/3, and complete submergence of the plants can be performed at the tillering stage for 1-3 d; this treatment will increase the space available for rice field water management/control and will improve rainfall resource utilization.

  1. Deep cultural ancestry and human development indicators across nation states

    PubMed Central

    Sookias, Roland B.; Passmore, Samuel

    2018-01-01

    How historical connections, events and cultural proximity can influence human development is being increasingly recognized. One aspect of history that has only recently begun to be examined is deep cultural ancestry, i.e. the vertical relationships of descent between cultures, which can be represented by a phylogenetic tree of descent. Here, we test whether deep cultural ancestry predicts the United Nations Human Development Index (HDI) for 44 Eurasian countries, using language ancestry as a proxy for cultural relatedness and controlling for three additional factors—geographical proximity, religion and former communism. While cultural ancestry alone predicts HDI and its subcomponents (income, health and education indices), when geographical proximity is included only income and health indices remain significant and the effect is small. When communism and religion variables are included, cultural ancestry is no longer a significant predictor; communism significantly negatively predicts HDI, income and health indices, and Muslim percentage of the population significantly negatively predicts education index, although the latter result may not be robust. These findings indicate that geographical proximity and recent cultural history—especially communism—are more important than deep cultural factors in current human development and suggest the efficacy of modern policy initiatives is not tightly constrained by cultural ancestry. PMID:29765628

  2. Deep cultural ancestry and human development indicators across nation states.

    PubMed

    Sookias, Roland B; Passmore, Samuel; Atkinson, Quentin D

    2018-04-01

    How historical connections, events and cultural proximity can influence human development is being increasingly recognized. One aspect of history that has only recently begun to be examined is deep cultural ancestry, i.e. the vertical relationships of descent between cultures, which can be represented by a phylogenetic tree of descent. Here, we test whether deep cultural ancestry predicts the United Nations Human Development Index (HDI) for 44 Eurasian countries, using language ancestry as a proxy for cultural relatedness and controlling for three additional factors-geographical proximity, religion and former communism. While cultural ancestry alone predicts HDI and its subcomponents (income, health and education indices), when geographical proximity is included only income and health indices remain significant and the effect is small. When communism and religion variables are included, cultural ancestry is no longer a significant predictor; communism significantly negatively predicts HDI, income and health indices, and Muslim percentage of the population significantly negatively predicts education index, although the latter result may not be robust. These findings indicate that geographical proximity and recent cultural history-especially communism-are more important than deep cultural factors in current human development and suggest the efficacy of modern policy initiatives is not tightly constrained by cultural ancestry.

  3. Submerged passively-safe power plant

    DOEpatents

    Herring, J.S.

    1993-09-21

    The invention as presented consists of a submerged passively-safe power station including a pressurized water reactor capable of generating at least 600 MW of electricity, encased in a double hull vessel, and provides fresh water by using the spent thermal energy in a multistage flash desalination process. 8 figures.

  4. Reactive oxygen species mediate growth and death in submerged plants

    PubMed Central

    Steffens, Bianka; Steffen-Heins, Anja; Sauter, Margret

    2013-01-01

    Aquatic and semi-aquatic plants are well adapted to survive partial or complete submergence which is commonly accompanied by oxygen deprivation. The gaseous hormone ethylene controls a number of adaptive responses to submergence including adventitious root growth and aerenchyma formation. Reactive oxygen species (ROS) act as signaling intermediates in ethylene-controlled submergence adaptation and possibly also independent of ethylene. ROS levels are controlled by synthesis, enzymatic metabolism, and non-enzymatic scavenging. While the actors are by and large known, we still have to learn about altered ROS at the subcellular level and how they are brought about, and the signaling cascades that trigger a specific response. This review briefly summarizes our knowledge on the contribution of ROS to submergence adaptation and describes spectrophotometrical, histochemical, and live cell imaging detection methods that have been used to study changes in ROS abundance. Electron paramagnetic resonance (EPR) spectroscopy is introduced as a method that allows identification and quantification of specific ROS in cell compartments. The use of advanced technologies such as EPR spectroscopy will be necessary to untangle the intricate and partially interwoven signaling networks of ethylene and ROS. PMID:23761805

  5. Detecting submerged objects: the application of side scan sonar to forensic contexts.

    PubMed

    Schultz, John J; Healy, Carrie A; Parker, Kenneth; Lowers, Bim

    2013-09-10

    Forensic personnel must deal with numerous challenges when searching for submerged objects. While traditional water search methods have generally involved using dive teams, remotely operated vehicles (ROVs), and water scent dogs for cases involving submerged objects and bodies, law enforcement is increasingly integrating multiple methods that include geophysical technologies. There are numerous advantages for integrating geophysical technologies, such as side scan sonar and ground penetrating radar (GPR), with more traditional search methods. Overall, these methods decrease the time involved searching, in addition to increasing area searched. However, as with other search methods, there are advantages and disadvantages when using each method. For example, in instances with excessive aquatic vegetation or irregular bottom terrain, it may not be possible to discern a submersed body with side scan sonar. As a result, forensic personnel will have the highest rate of success during searches for submerged objects when integrating multiple search methods, including deploying multiple geophysical technologies. The goal of this paper is to discuss the methodology of various search methods that are employed for submerged objects and how these various methods can be integrated as part of a comprehensive protocol for water searches depending upon the type of underwater terrain. In addition, two successful case studies involving the search and recovery of a submerged human body using side scan sonar are presented to illustrate the successful application of integrating a geophysical technology with divers when searching for a submerged object. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  6. Gas film retention and underwater photosynthesis during field submergence of four contrasting rice genotypes

    PubMed Central

    Winkel, Anders; Pedersen, Ole; Ella, Evangelina; Ismail, Abdelbagi M.; Colmer, Timothy D.

    2014-01-01

    Floods can completely submerge some rice (Oryza sativa L.) fields. Leaves of rice have gas films that aid O2 and CO2 exchange under water. The present study explored the relationship between gas film persistence and underwater net photosynthesis (PN) as influenced by genotype and submergence duration. Four contrasting genotypes (FR13A, IR42, Swarna, and Swarna-Sub1) were submerged for 13 days in the field and leaf gas films, chlorophyll, and the capacity for underwater PN at near ambient and high CO2 were assessed with time of submergence. At high CO2 during the PN assay, all genotypes initially showed high rates of underwater PN, and this rate was not affected by time of submergence in FR13A. This superior photosynthetic performance of FR13A was not evident in Swarna-Sub1 (carrying the SUB1 QTL) and the declines in underwater PN in both Swarna-Sub1 and Swarna were equal to that in IR42. At near ambient CO2 concentration, underwater PN declined in all four genotypes and this corresponded with loss of leaf gas films with time of submergence. FR13A retained leaf gas films moderately longer than the other genotypes, but gas film retention was not linked to SUB1. Diverse rice germplasm should be screened for gas film persistence during submergence, as this trait could potentially increase carbohydrate status and internal aeration owing to increased underwater PN, which contributes to submergence tolerance in rice. PMID:24759881

  7. Wave Transformation and Attenuation near the Submerged Breakwater and Vegetation: Field investigation and Numerical simulation

    NASA Astrophysics Data System (ADS)

    Shin, S.; Kim, I.; Hur, D.; Lee, W.; Kim, J.; Lee, J. L.; Lee, H. S.; Kim, H. G.

    2016-12-01

    The large scale decreasing of beach width in the Anmok beach had occurred due to the coastal erosion caused by the short-term events, such as unexpected high waves and storms. Hence, the city officials decided the installation of hard construction, and the first submerged breakwater, which is a structure that parallels the beach and support as a wave absorber, was constructed on this beach in September 2014. In order to deduce the correlation equation of the transmitted wave heights (TWH) after the breakwater installed, we have observed the transmitted wave height at four sites nearby the breakwater, two wave gauges were mounted on the front side of the breakwater, and the others were placed in the behind side of it. We found that the TWH using the formula suggested by Takayama et al. (1985) for the submerged breakwaters (crown elevation: D.L. (-)0.5 m, crown width: 18.5 m, bottom width: 22.8 m) was 0.501, whereas the value which was measured by the wave gauge showed 0.547. Therefore, we suggested a formula for estimating the TWH based on the field observation data. 3D numerical model (LES-WASS-3D) was employed to estimate hydrodynamic chracteristics near the submerged breakwater. The results showed that the predicted TWH agreed well with the field field observation data results. In order to consider evironmet-friendly measure, the model also simulated the wave transformation and attenuation phenomina near the area of submerged vegetation. The model was already verified in two-dimensional laboratory experiments. In this study, the numerical model is used to predict the three-dimensional wave transformation and attenucation through the underwater vegetation. The results are compared with those in the case of submerged breakwater. This research was partially supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2016R1A2B4015419) and Korean Institute of Marine Science and Technology

  8. Gas film retention and underwater photosynthesis during field submergence of four contrasting rice genotypes.

    PubMed

    Winkel, Anders; Pedersen, Ole; Ella, Evangelina; Ismail, Abdelbagi M; Colmer, Timothy D

    2014-07-01

    Floods can completely submerge some rice (Oryza sativa L.) fields. Leaves of rice have gas films that aid O2 and CO2 exchange under water. The present study explored the relationship between gas film persistence and underwater net photosynthesis (PN) as influenced by genotype and submergence duration. Four contrasting genotypes (FR13A, IR42, Swarna, and Swarna-Sub1) were submerged for 13 days in the field and leaf gas films, chlorophyll, and the capacity for underwater PN at near ambient and high CO2 were assessed with time of submergence. At high CO2 during the PN assay, all genotypes initially showed high rates of underwater PN, and this rate was not affected by time of submergence in FR13A. This superior photosynthetic performance of FR13A was not evident in Swarna-Sub1 (carrying the SUB1 QTL) and the declines in underwater PN in both Swarna-Sub1 and Swarna were equal to that in IR42. At near ambient CO2 concentration, underwater PN declined in all four genotypes and this corresponded with loss of leaf gas films with time of submergence. FR13A retained leaf gas films moderately longer than the other genotypes, but gas film retention was not linked to SUB1. Diverse rice germplasm should be screened for gas film persistence during submergence, as this trait could potentially increase carbohydrate status and internal aeration owing to increased underwater PN, which contributes to submergence tolerance in rice. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  9. [Influence of Submerged Plants on Microbial Community Structure in Sediment of Hongze Lake].

    PubMed

    Zhang, Ding-yu; Zhang, Ting-xi; Dong, Dan-ping; Li, De-fang; Wang, Guo-xiang

    2016-05-15

    Phospholipid fatty acids (PLFAs) method was applied to analyze the influence of submerged plants on sediment microbial community structure, in order to investigate the changes of sediment microbial community structure for different kinds of the submerged plants in different growth periods. Particularly, Potamogeton crispus L., Potamogeton pectinatus L and the mixed group were chosen as the typical submerged plants in Hongze Lake for investigation in this paper. The results indicated that the change of total PLFAs in different periods was significant, on the contrary, the PLFA change for different groups in the same period was insignificant. The values of G⁺ PLFA/G⁻ PLFA in the submerged plant group were also highly related to the different growth periods, which demonstrated that the root function of the submerged plant had a severe impact on the microbial community in sediment. Furthermore, some environmental factors, such as Temperature, pH, TOC and DO, were correlated to characteristic phospholipid of PLFAs in sediment, which means the environmental factors could also affect the microbial community structure.

  10. Submergence Confers Immunity Mediated by the WRKY22 Transcription Factor in Arabidopsis[W

    PubMed Central

    Hsu, Fu-Chiun; Chou, Mei-Yi; Chou, Shu-Jen; Li, Ya-Ru; Peng, Hsiao-Ping; Shih, Ming-Che

    2013-01-01

    Transcriptional control plays an important role in regulating submergence responses in plants. Although numerous genes are highly induced during hypoxia, their individual roles in hypoxic responses are still poorly understood. Here, we found that expression of genes that encode members of the WRKY transcription factor family was rapidly and strongly induced upon submergence in Arabidopsis thaliana, and this induction correlated with induction of a large portion of innate immunity marker genes. Furthermore, prior submergence treatment conferred higher resistance to the bacterial pathogen Pseudomonas syringae in Arabidopsis. Among the WRKY genes tested, WRKY22 had the highest level of induction during the early stages of submergence. Compared with the wild type, WRKY22 T-DNA insertion mutants wrky22-1 and wrky22-2 had lower disease resistance and lower induction of innate immunity markers, such as FLG22-INDUCED RECEPTOR-LIKE KINASE1 (FRK1) and WRKY53, after submergence. Furthermore, transcriptomic analyses of wrky22-2 and chromatin immunoprecipitation identified several potential targets of WRKY22, which included genes encoding a TIR domain–containing protein, a plant peptide hormone, and many OLIGO PEPTIDE TRANSPORTER genes, all of which may lead to induction of innate immunity. In conclusion, we propose that submergence triggers innate immunity in Arabidopsis via WRKY22, a response that may protect against a higher probability of pathogen infection either during or after flooding. PMID:23897923

  11. Rice SUB1A constrains remodeling of the transcriptome and metabolome during submergence and post-submergence recovery”.

    USDA-ARS?s Scientific Manuscript database

    The rice (Oryza sativa L.) ethylene-responsive transcription factor SUB1A confers tolerance to prolonged, complete submergence by limiting underwater elongation growth. Rice encoding SUB1A-1 also recovers photosynthetic function and re-commences development towards flowering more rapidly after desu...

  12. Geodynamic settings of microcontinents, non-volcanic islands and submerged continental marginal plateau formation

    NASA Astrophysics Data System (ADS)

    Dubinin, Evgeny; Grokholsky, Andrey; Makushkina, Anna

    2016-04-01

    Complex process of continental lithosphere breakup is often accompanied by full or semi isolation of small continental blocks from the parent continent such as microcontinents or submerged marginal plateaus. We present different types of continental blocks formed in various geodynamic settings. The process depends on thermo-mechanical properties of rifting. 1) The continental blocks fully isolated from the parent continent. This kind of blocks exist in submerged form (Elan Bank, the Jan-Mayen Ridge, Zenith Plateau, Gulden Draak Knoll, Batavia Knoll) and in non-submerged form in case of large block size. Most of listed submerged blocks are formed in proximity of hot-spot or plume. 2) The continental blocks semi-isolated from the parent continent. Exmouth Plateau, Vøring, Agulhas, Naturaliste are submerged continental plateaus of the indicated category; Sri Lanka, Tasmania, Socotra are islands adjacent to continent here. Nowadays illustration of this setting is the Sinai block located between the two continental rifts. 3) The submerged linear continental blocks formed by the continental rifting along margin (the Lomonosov Ridge). Suggested evolution of this paragraph is the rift propagation along existing transtensional (or another type) transform fault. Future example of this type might be the California Peninsula block, detached from the North American plate by the rifting within San-Andreas fault. 4) The submerged continental blocks formed by extensional processes as the result of asthenosphere flow and shear deformations. Examples are submerged blocks in the central and southern Scotia Sea (Terror Bank, Protector Basin, Discovery Bank, Bruce Bank etc.). 5) The continental blocks formed in the transform fault systems originated in setting of contradict rifts propagation in presence of structure barriers, rifts are shifted by several hundreds kilometers from each other. Examples of this geodynamic setting are Equatorial Atlantic at the initial development stage

  13. Wave‐induced Hydraulic Forces on Submerged Aquatic Plants in Shallow Lakes

    PubMed Central

    SCHUTTEN, J.; DAINTY, J.; DAVY, A. J.

    2004-01-01

    • Background and Aims Hydraulic pulling forces arising from wave action are likely to limit the presence of freshwater macrophytes in shallow lakes, particularly those with soft sediments. The aim of this study was to develop and test experimentally simple models, based on linear wave theory for deep water, to predict such forces on individual shoots. • Methods Models were derived theoretically from the action of the vertical component of the orbital velocity of the waves on shoot size. Alternative shoot‐size descriptors (plan‐form area or dry mass) and alternative distributions of the shoot material along its length (cylinder or inverted cone) were examined. Models were tested experimentally in a flume that generated sinusoidal waves which lasted 1 s and were up to 0·2 m high. Hydraulic pulling forces were measured on plastic replicas of Elodea sp. and on six species of real plants with varying morphology (Ceratophyllum demersum, Chara intermedia, Elodea canadensis, Myriophyllum spicatum, Potamogeton natans and Potamogeton obtusifolius). • Key Results Measurements on the plastic replicas confirmed predicted relationships between force and wave phase, wave height and plant submergence depth. Predicted and measured forces were linearly related over all combinations of wave height and submergence depth. Measured forces on real plants were linearly related to theoretically derived predictors of the hydraulic forces (integrals of the products of the vertical orbital velocity raised to the power 1·5 and shoot size). • Conclusions The general applicability of the simplified wave equations used was confirmed. Overall, dry mass and plan‐form area performed similarly well as shoot‐size descriptors, as did the conical or cylindrical models of shoot distribution. The utility of the modelling approach in predicting hydraulic pulling forces from relatively simple plant and environmental measurements was validated over a wide range of forces, plant sizes and

  14. Wave-induced hydraulic forces on submerged aquatic plants in shallow lakes.

    PubMed

    Schutten, J; Dainty, J; Davy, A J

    2004-03-01

    Hydraulic pulling forces arising from wave action are likely to limit the presence of freshwater macrophytes in shallow lakes, particularly those with soft sediments. The aim of this study was to develop and test experimentally simple models, based on linear wave theory for deep water, to predict such forces on individual shoots. Models were derived theoretically from the action of the vertical component of the orbital velocity of the waves on shoot size. Alternative shoot-size descriptors (plan-form area or dry mass) and alternative distributions of the shoot material along its length (cylinder or inverted cone) were examined. Models were tested experimentally in a flume that generated sinusoidal waves which lasted 1 s and were up to 0.2 m high. Hydraulic pulling forces were measured on plastic replicas of Elodea sp. and on six species of real plants with varying morphology (Ceratophyllum demersum, Chara intermedia, Elodea canadensis, Myriophyllum spicatum, Potamogeton natans and Potamogeton obtusifolius). Measurements on the plastic replicas confirmed predicted relationships between force and wave phase, wave height and plant submergence depth. Predicted and measured forces were linearly related over all combinations of wave height and submergence depth. Measured forces on real plants were linearly related to theoretically derived predictors of the hydraulic forces (integrals of the products of the vertical orbital velocity raised to the power 1.5 and shoot size). The general applicability of the simplified wave equations used was confirmed. Overall, dry mass and plan-form area performed similarly well as shoot-size descriptors, as did the conical or cylindrical models of shoot distribution. The utility of the modelling approach in predicting hydraulic pulling forces from relatively simple plant and environmental measurements was validated over a wide range of forces, plant sizes and species.

  15. Deep canyon and subalpine riparian and wetland plant associations of the Malheur, Umatilla, and Wallowa-Whitman National Forests.

    Treesearch

    Aaron F. Wells

    2006-01-01

    This guide presents a classification of the deep canyon and subalpine riparian and wetland vegetation types of the Malheur, Umatilla, and Wallowa-Whitman National Forests. A primary goal of the deep canyon and subalpine riparian and wetland classification was a seamless linkage with the midmontane northeastern Oregon riparian and wetland classification provided by...

  16. Activation of respiratory muscles does not occur during cold-submergence in bullfrogs, Lithobates catesbeianus.

    PubMed

    Santin, Joseph M; Hartzler, Lynn K

    2017-04-01

    Semiaquatic frogs may not breathe air for several months because they overwinter in ice-covered ponds. In contrast to many vertebrates that experience decreased motor performance after inactivity, bullfrogs, Lithobates catesbeianus , retain functional respiratory motor processes following cold-submergence. Unlike mammalian hibernators with unloaded limb muscles and inactive locomotor systems, respiratory mechanics of frogs counterintuitively allow for ventilatory maneuvers when submerged. Thus, we hypothesized that bullfrogs generate respiratory motor patterns during cold-submergence to avoid disuse and preserve motor performance. Accordingly, we measured activity of respiratory muscles (buccal floor compressor and glottal dilator) via electromyography in freely behaving bullfrogs at 20 and 2°C. Although we confirm that ventilation cycles occur underwater at 20°C, bullfrogs did not activate either respiratory muscle when submerged acutely or chronically at 2°C. We conclude that cold-submerged bullfrogs endure respiratory motor inactivity, implying that other mechanisms, excluding underwater muscle activation, maintain a functional respiratory motor system throughout overwintering. © 2017. Published by The Company of Biologists Ltd.

  17. Antioxidant activity of seedling growth in selected soybean genotypes (Glycine max (L.) Merrill) responses of submergence

    NASA Astrophysics Data System (ADS)

    Damanik, R. I.; Marbun, P.; Sihombing, L.

    2016-08-01

    In order to better understand the physiological and biochemical responses relating to direct seeding establishment in soybeans, the plant growth rate and antioxidative defense responses of seedlings in seven Indonesian soybean genotypes (Anjasmoro, Detam-1, Detam-2, Dieng, Grobogan, Tanggamus, and Willis) at different submergence periods (4, and 8 days) were examined. Twelve-day old seedlings were hydroponically grown in limited oxygen conditions. The results showed that the chlorophyll content in soybean seedlings was reduced beginning as early as 4 d under submerged condition, except for Detam-1, Detam-2, and Grobogan genotypes. The dry weight and protein concentration of seedlings were significantly higher at control condition (0 d) than those in submerged condition. The activities of superoxide dismutase (SOD) increased linearly until 8 d submerged for all genotypes. On the other hand, our results showed that catalase (CAT) and ascorbate peroxidase (APX) activities did not work together, meaning that CAT is activated and APX deactivated, or vice versa, in response to submergence conditions, except for Grobogan and Tanggamus genotypes which had an effect on both CAT and APX activities. Submergence stress led to a significant increase in glutathione reductase (GR) together with APX activity for Detam-2 and Dieng genotypes at 8 d submerged.

  18. Current progress on truffle submerged fermentation: a promising alternative to its fruiting bodies.

    PubMed

    Tang, Ya-Jie; Liu, Rui-Sang; Li, Hong-Mei

    2015-03-01

    Truffle (Tuber spp.), also known as "underground gold," is popular in various cuisines because of its unique and characteristic aroma. Currently, truffle fruiting bodies are mostly obtained from nature and semi-artificial cultivation. However, the former source is scarce, and the latter is time-consuming, usually taking 4 to 12 years before harvest of the fruiting body. The truffle submerged fermentation process was first developed in Tang's lab as an alternative to its fruiting bodies. To the best of our knowledge, most reports of truffle submerged fermentation come from Tang's group. This review examines the current state of the truffle submerged fermentation process. First, the strategy to optimize the truffle submerged fermentation process is summarized; the final conditions yielded not only the highest reported truffle biomass but also the highest production of extracellular and intracellular polysaccharides. Second, the comparison of metabolites produced by truffle fermentation and fruiting bodies is presented, and the former were superior to the latter. Third, metabolites (i.e., volatile organic compounds, equivalent umami concentration, and sterol) derived from truffle fermentation could be regulated by fermentation process optimization. These findings indicated that submerged fermentation of truffles can be used for commercial production of biomass and metabolites as a promising alternative to generating its fruiting bodies in bioreactor.

  19. Effects of stern-foil submerged elevation on the lift and drag of a hydrofoil craft

    NASA Astrophysics Data System (ADS)

    Suastika, K.; Apriansyah

    2018-03-01

    Effects of the stern-foil submerged elevation on the lift and drag of a hydrofoil craft are studied by using computational fluid dynamics (CFD) and by considering three alternative stern-foil submerged elevations. The submerged elevation of the front foil is kept constant in all the alternatives. From among the alternatives, the deepest stern-foil placement results in the highest stern-foil lift with the highest foil’s lift-to-drag ratio. However, considering the lift-to-drag ratio of the whole foil-strut-hull system, the shallowest stern-foil placement results in the highest lift-to-drag ratio. The struts and the foil’s submerged elevation significantly affects the drag of the whole foil-strut-hull system.

  20. Detecting submerged features in water: modeling, sensors, and measurements

    NASA Astrophysics Data System (ADS)

    Bostater, Charles R., Jr.; Bassetti, Luce

    2004-11-01

    It is becoming more important to understand the remote sensing systems and associated autonomous or semi-autonomous methodologies (robotic & mechatronics) that may be utilized in freshwater and marine aquatic environments. This need comes from several issues related not only to advances in our scientific understanding and technological capabilities, but also from the desire to insure that the risk associated with UXO (unexploded ordnance), related submerged mines, as well as submerged targets (such as submerged aquatic vegetation) and debris left from previous human activities are remotely sensed and identified followed by reduced risks through detection and removal. This paper will describe (a) remote sensing systems, (b) platforms (fixed and mobile, as well as to demonstrate (c) the value of thinking in terms of scalability as well as modularity in the design and application of new systems now being constructed within our laboratory and other laboratories, as well as future systems. New remote sensing systems - moving or fixed sensing systems, as well as autonomous or semi-autonomous robotic and mechatronic systems will be essential to secure domestic preparedness for humanitarian reasons. These remote sensing systems hold tremendous value, if thoughtfully designed for other applications which include environmental monitoring in ambient environments.

  1. How Deep-Sea Wood Falls Sustain Chemosynthetic Life

    PubMed Central

    Bienhold, Christina; Pop Ristova, Petra; Wenzhöfer, Frank; Dittmar, Thorsten; Boetius, Antje

    2013-01-01

    Large organic food falls to the deep sea – such as whale carcasses and wood logs – are known to serve as stepping stones for the dispersal of highly adapted chemosynthetic organisms inhabiting hot vents and cold seeps. Here we investigated the biogeochemical and microbiological processes leading to the development of sulfidic niches by deploying wood colonization experiments at a depth of 1690 m in the Eastern Mediterranean for one year. Wood-boring bivalves of the genus Xylophaga played a key role in the degradation of the wood logs, facilitating the development of anoxic zones and anaerobic microbial processes such as sulfate reduction. Fauna and bacteria associated with the wood included types reported from other deep-sea habitats including chemosynthetic ecosystems, confirming the potential role of large organic food falls as biodiversity hot spots and stepping stones for vent and seep communities. Specific bacterial communities developed on and around the wood falls within one year and were distinct from freshly submerged wood and background sediments. These included sulfate-reducing and cellulolytic bacterial taxa, which are likely to play an important role in the utilization of wood by chemosynthetic life and other deep-sea animals. PMID:23301092

  2. Submerged flow bridge scour under clear water conditions

    DOT National Transportation Integrated Search

    2012-09-01

    Prediction of pressure flow (vertical contraction) scour underneath a partially or fully submerged bridge superstructure : in an extreme flood event is crucial for bridge safety. An experimentally and numerically calibrated formulation is : developed...

  3. Durability performance of submerged concrete structures - phase 2.

    DOT National Transportation Integrated Search

    2015-09-01

    This project determined that severe corrosion of steel can occur in the submerged : portions of reinforced concrete structures in marine environments. Field studies of decommissioned : pilings from Florida bridges revealed multiple instances of stron...

  4. Submerged beachrock preservation in the context of wave ravinement

    NASA Astrophysics Data System (ADS)

    Pretorius, Lauren; Green, Andrew N.; Andrew Cooper, J.

    2018-02-01

    This study examines a Holocene-aged submerged shoreline, Limestone Reef, located in the shallow subtidal zone of South Africa's east coast. It comprises an elongate, coast-oblique, slab-like outcrop of beachrock situated above the contemporary fair-weather wave base. It is currently undergoing mechanical disintegration. Its unique and rare preservation in a high-energy setting affords an opportunity to examine the mechanical processes occurring during wave ravinement associated with rising sea level. The submerged shoreline and the adjacent shoreface were examined using high-resolution seismic reflection, side-scan sonar and shallow-water multibeam echosounding techniques. Limestone Reef rests on top of unconsolidated Holocene deposits. The structure's surface is characterised by reef-perpendicular gullies with rubble derived from the slab fringing its seaward edge. Limestone Reef slopes gently seawards and has a steep landward-facing edge where gullies are most prominently developed. Teardrop-shaped rippled scour depressions, marked by high backscatter, are located seawards of the submerged shoreline. These elongate in a seaward direction and are filled with bioclastic gravels and residual rubble from Limestone Reef. The gullies in the upstanding structure are indicative of wave plucking and abrasion of the shoreline. The material exposed by the rippled scour depressions is identical to that comprising the postglacial ravinement surface identified in the offshore stratigraphy. These deposits are considered to represent the contemporary, actively forming wave ravinement surface. The results suggest that wave ravinement of submerged shorelines is a discontinuous process dominated by the seaward entrainment of material from its landward edge controlled by high-energy drawback during storm surges. The ravinement process appears to operate at the seasonal scale and averages out over the long-term millennial scale for the continuous surface.

  5. EAARL Submerged Topography - U.S. Virgin Islands 2003

    USGS Publications Warehouse

    Nayegandhi, Amar; Brock, John C.; Wright, C. Wayne; Stevens, Sara; Yates, Xan; Bonisteel, Jamie M.

    2008-01-01

    These remotely sensed, geographically referenced elevation measurements of Lidar-derived submerged topography were produced as a collaborative effort between the U.S. Geological Survey (USGS), Florida Integrated Science Center (FISC), St. Petersburg, FL; the National Park Service (NPS), South Florida-Caribbean Network, Miami, FL; and the National Aeronautics and Space Administration (NASA), Wallops Flight Facility, VA. This project provides highly detailed and accurate bathymetric datasets of a portion of the U.S. Virgin Islands, acquired on April 21, 23, and 30, May 2, and June 14 and 17, 2003. The datasets are made available for use as a management tool to research scientists and natural resource managers. An innovative airborne Lidar instrument originally developed at the NASA Wallops Flight Facility, and known as the Experimental Advanced Airborne Research Lidar (EAARL), was used during data acquisition. The EAARL system is a raster-scanning, waveform-resolving, green-wavelength (532-nanometer) Lidar designed to map near-shore bathymetry, topography, and vegetation structure simultaneously. The EAARL sensor suite includes the raster-scanning, water-penetrating full-waveform adaptive Lidar, a down-looking red-green-blue (RGB) digital camera, a high-resolution multi-spectral color infrared (CIR) camera, two precision dual-frequency kinematic carrier-phase GPS receivers, and an integrated miniature digital inertial measurement unit, which provide for submeter georeferencing of each laser sample. The nominal EAARL platform is a twin-engine Cessna 310 aircraft, but the instrument may be deployed on a range of light aircraft. A single pilot, a Lidar operator, and a data analyst constitute the crew for most survey operations. This sensor has the potential to make significant contributions in measuring sub-aerial and submarine coastal topography within cross-environmental surveys. Elevation measurements were collected over the survey area using the EAARL system, and

  6. Submerged AUV Charging Station

    NASA Technical Reports Server (NTRS)

    Jones, Jack A.; Chao, Yi; Curtin, Thomas

    2014-01-01

    Autonomous Underwater Vehicles (AUVs) are becoming increasingly important for military surveillance and mine detection. Most AUVs are battery powered and have limited lifetimes of a few days to a few weeks. This greatly limits the distance that AUVs can travel underwater. Using a series of submerged AUV charging stations, AUVs could travel a limited distance to the next charging station, recharge its batteries, and continue to the next charging station, thus traveling great distances in a relatively short time, similar to the Old West “Pony Express.” One solution is to use temperature differences at various depths in the ocean to produce electricity, which is then stored in a submerged battery. It is preferred to have the upper buoy submerged a reasonable distance below the surface, so as not to be seen from above and not to be inadvertently destroyed by storms or ocean going vessels. In a previous invention, a phase change material (PCM) is melted (expanded) at warm temperatures, for example, 15 °C, and frozen (contracted) at cooler temperatures, for example, 8 °C. Tubes containing the PCM, which could be paraffin such as pentadecane, would be inserted into a container filled with hydraulic oil. When the PCM is melted (expanded), it pushes the oil out into a container that is pressurized to about 3,000 psi (approx equals 20.7 MPa). When a valve is opened, the high-pressure oil passes through a hydraulic motor, which turns a generator and charges a battery. The low-pressure oil is finally reabsorbed into the PCM canister when the PCM tubes are frozen (contracted). Some of the electricity produced could be used to control an external bladder or a motor to the tether line, such that depth cycling is continued for a very long period of time. Alternatively, after the electricity is generated by the hydraulic motor, the exiting low-pressure oil from the hydraulic motor could be vented directly to an external bladder on the AUV, such that filling of the bladder

  7. Crestal bone loss around submerged and nonsubmerged dental implants: A systematic review.

    PubMed

    Al Amri, Mohammad D

    2016-05-01

    To my knowledge, there is no systematic review of crestal bone loss (CBL) around submerged and nonsubmerged dental implants. The purpose of this review was to systematically assess CBL around submerged and nonsubmerged dental implants. The addressed focused question was, "Does crestal and subcrestal placement of dental implants influence crestal bone levels?" Databases were searched from 1986 through October 2015 using different combinations of the following keywords: crestal, sub-crestal, bone loss, dental implant, submerged, and nonsubmerged. Reference lists of potentially relevant original and review articles were hand-searched to identify any further studies. Letters to the editor, case reports, commentaries, studies on platform-switched implants, and studies published in languages other than English were excluded. In total, 13 studies (6 human and 7 animal), which were performed at universities, were included. In the human studies, the number of participants ranged from 8 to 84 individuals. The follow-up period ranged from 1 to 5 years. CBL at the test sites ranged from 0.17 mm to 0.9 mm and at control sites from 0.02 mm to 1.4 mm. Five human studies reported no significant difference in CBL around implants placed at the test and control sites. All animal studies were performed in dogs with a mean age ranging from 1 to approximately 2 years. The follow-up period ranged from 2 to 6 months. Four animal studies reported no significant difference in CBL around submerged and nonsubmerged implants. No significant difference in CBL was found around submerged and nonsubmerged dental implants. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  8. Submerged karst landforms observed by multibeam bathymetric survey in Nagura Bay, Ishigaki Island, southwestern Japan

    NASA Astrophysics Data System (ADS)

    Kan, Hironobu; Urata, Kensaku; Nagao, Masayuki; Hori, Nobuyuki; Fujita, Kazuhiko; Yokoyama, Yusuke; Nakashima, Yosuke; Ohashi, Tomoya; Goto, Kazuhisa; Suzuki, Atsushi

    2015-01-01

    Submerged tropical karst features were discovered in Nagura Bay on Ishigaki Island in the southern Ryukyu Islands, Japan. The coastal seafloor at depths shallower than ~ 130 m has been subjected to repeated and alternating subaerial erosion and sedimentation during periods of Quaternary sea-level lowstands. We conducted a broadband multibeam survey in the central area of Nagura Bay (1.85 × 2.7 km) and visualized the high-resolution bathymetric results over a depth range of 1.6-58.5 m. Various types of humid tropical karst landforms were found to coexist within the bay, including fluviokarst, doline karst, cockpit karst, polygonal karst, uvalas, and mega-dolines. Although these submerged karst landforms are covered by thick postglacial reef and reef sediments, their shapes and sizes are distinct from those associated with coral reef geomorphology. The submerged landscape of Nagura Bay likely formed during multiple glacial and interglacial periods. According to our bathymetric results and the aerial photographs of the coastal area, this submerged karst landscape appears to have developed throughout Nagura Bay (i.e., over an area of approximately 6 × 5 km) and represents the largest submerged karst in Japan.

  9. Submergence tolerance conferred by Sub1A is mediated by SLR1 and SLRL1 restriction of gibberellin responses in rice

    PubMed Central

    Fukao, Takeshi; Bailey-Serres, Julia

    2008-01-01

    Submergence-tolerant rice maintains viability during complete submergence by limiting underwater elongation until floodwaters recede. Acclimation responses to submergence are coordinated by the submergence-inducible Sub1A, which encodes an ethylene-responsive factor-type transcription factor (ERF). Sub1A is limited to tolerant genotypes and sufficient to confer submergence tolerance to intolerant accessions. Here we evaluated the role of Sub1A in the integration of ethylene, abscisic acid (ABA), and gibberellin (GA) signaling during submergence. The submergence-stimulated decrease in ABA content was Sub1A-independent, whereas GA-mediated underwater elongation was significantly restricted by Sub1A. Transgenics that ectopically express Sub1A displayed classical GA-insensitive phenotypes, leading to the hypothesis that Sub1A limits the response to GA. Notably Sub1A increased the accumulation of the GA signaling repressors Slender Rice-1 (SLR1) and SLR1 Like-1 (SLRL1) and concomitantly diminished GA-inducible gene expression under submerged conditions. In the Sub1A overexpression line, SLR1 protein levels declined under prolonged submergence but were accompanied by an increase in accumulation of SLRL1, which lacks the DELLA domain. In the presence of Sub1A, the increase in these GA signaling repressors and decrease in GA responsiveness were stimulated by ethylene, which promotes Sub1A expression. Conversely, ethylene promoted GA responsiveness and shoot elongation in submergence-intolerant lines. Together, these results demonstrate that Sub1A limits ethylene-promoted GA responsiveness during submergence by augmenting accumulation of the GA signaling repressors SLR1 and SLRL1. PMID:18936491

  10. Contrasting submergence tolerance in two species of stem-succulent halophytes is not determined by differences in stem internal oxygen dynamics.

    PubMed

    Konnerup, Dennis; Moir-Barnetson, Louis; Pedersen, Ole; Veneklaas, Erik J; Colmer, Timothy D

    2015-02-01

    Many stem-succulent halophytes experience regular or episodic flooding events, which may compromise gas exchange and reduce survival rates. This study assesses submergence tolerance, gas exchange and tissue oxygen (O2) status of two stem-succulent halophytes with different stem diameters and from different elevations of an inland marsh. Responses to complete submergence in terms of stem internal O2 dynamics, photosynthesis and respiration were studied for the two halophytic stem-succulents Tecticornia auriculata and T. medusa. Plants were submerged in a glasshouse experiment for 3, 6 and 12 d and O2 levels within stems were measured with microelectrodes. Photosynthesis by stems in air after de-submergence was also measured. Tecticornia medusa showed 100 % survival in all submergence durations whereas T. auriculata did not survive longer than 6 d of submergence. O2 profiles and time traces showed that when submerged in water at air-equilibrium, the thicker stems of T. medusa were severely hypoxic (close to anoxic) when in darkness, whereas the smaller diameter stems of T. auriculata were moderately hypoxic. During light periods, underwater photosynthesis increased the internal O2 concentrations in the succulent stems of both species. Stems of T. auriculata temporally retained a gas film when first submerged, whereas T. medusa did not. The lower O2 in T. medusa than in T. auriculata when submerged in darkness was largely attributed to a less permeable epidermis. The submergence sensitivity of T. auriculata was associated with swelling and rupturing of the succulent stem tissues, which did not occur in T. medusa. The higher submergence tolerance of T. medusa was not associated with better internal aeration of stems. Rather, this species has poor internal aeration of the succulent stems due to its less permeable epidermis; the low epidermal permeability might be related to resistance to swelling of succulent stem tissues when submerged. © The Author 2014. Published by

  11. Sudden, probably coseismic submergence of Holocene trees and grass in coastal Washington State

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Atwater, B.F.; Yamaguchi, D.K.

    Growth-position plant fossils in coastal Washington State imply a suddenness of Holocene submergence that is better explained coseismic lowering of the land than be decade- or century-long rise of the sea. These fossils include western red cedar and Sitka spruce whose death probably resulted from estuarine submergence close to 300 years ago. Rings in eroded, bark-free trunks of the red cedar show that growth remained normal within decades of death. Rings in buried, bark-bearing stumps of the spruce further show normal growth continuing until the year of death. Other growth-position fossils implying sudden submergence include the stems and leaves ofmore » salt-marsh grass entombed in tide-flat mud close to 300 years ago and roughly 1,700 and 3,100 years ago. The preservation of these stems and leaves shows that submergence and initial burial outpaced decomposition, which appears to take just a few years in modern salt marshes. In some places the stems and leaves close to 300 year old are surrounded by sand left by an extraordinary, landward-directed surge-probably a tsunami from a great thrust earthquake on the Cascadia subduction zone.« less

  12. METHODS TO DEFINE MARSH EVALUATION AND PERCENT SUBMERGENCE

    EPA Science Inventory

    Elevation can determine the percentage submergence from tides and therefore is one of the controlling factors for plant zonation within salt marshes. To make comparisons among plants from various salt marshes throughout Narragansett Bay, Rhode Island, a method was developed to es...

  13. Vibration analysis of partially cracked plate submerged in fluid

    NASA Astrophysics Data System (ADS)

    Soni, Shashank; Jain, N. K.; Joshi, P. V.

    2018-01-01

    The present work proposes an analytical model for vibration analysis of partially cracked rectangular plates coupled with fluid medium. The governing equation of motion for the isotropic plate based on the classical plate theory is modified to accommodate a part through continuous line crack according to simplified line spring model. The influence of surrounding fluid medium is incorporated in the governing equation in the form of inertia effects based on velocity potential function and Bernoulli's equations. Both partially and totally submerged plate configurations are considered. The governing equation also considers the in-plane stretching due to lateral deflection in the form of in-plane forces which introduces geometric non-linearity into the system. The fundamental frequencies are evaluated by expressing the lateral deflection in terms of modal functions. The assessment of the present results is carried out for intact submerged plate as to the best of the author's knowledge the literature lacks in analytical results for submerged cracked plates. New results for fundamental frequencies are presented as affected by crack length, fluid level, fluid density and immersed depth of plate. By employing the method of multiple scales, the frequency response and peak amplitude of the cracked structure is analyzed. The non-linear frequency response curves show the phenomenon of bending hardening or softening and the effect of fluid dynamic pressure on the response of the cracked plate.

  14. Elevation dynamics in a restored versus a submerging salt marsh in Long Island Sound

    USGS Publications Warehouse

    Anisfeld, Shimon C.; Hill, Troy D.; Cahoon, Donald R.

    2016-01-01

    Accelerated sea-level rise (SLR) poses the threat of salt marsh submergence, especially in marshes that are relatively low-lying. At the same time, restoration efforts are producing new low-lying marshes, many of which are thriving and avoiding submergence. To understand the causes of these different fates, we studied two Long Island Sound marshes: one that is experiencing submergence and mudflat expansion, and one that is undergoing successful restoration. We examined sedimentation using a variety of methods, each of which captures different time periods and different aspects of marsh elevation change: surface-elevation tables, marker horizons, sediment cores, and sediment traps. We also studied marsh hydrology, productivity, respiration, nutrient content, and suspended sediment. We found that, despite the expansion of mudflat in the submerging marsh, the areas that remain vegetated have been gaining elevation at roughly the rate of SLR over the last 10 years. However, this elevation gain was only possible thanks to an increase in belowground volume, which may be a temporary response to waterlogging. In addition, accretion rates in the first half of the twentieth century were much lower than current rates, so century-scale accretion in the submerging marsh was lower than SLR. In contrast, at the restored marsh, accretion rates are now averaging about 10 mm yr−1 (several times the rate of SLR), much higher than before restoration. The main cause of the different trajectories at the two marshes appeared to be the availability of suspended sediment, which was much higher in the restored marsh. We considered and rejected alternative hypotheses, including differences in tidal flooding, plant productivity, and nutrient loading. In the submerging marsh, suspended and deposited sediment had relatively high organic content, which may be a useful indicator of sediment starvation.

  15. Internal aeration of paddy field rice (Oryza sativa) during complete submergence---importance of light and floodwater O2.

    PubMed

    Winkel, Anders; Colmer, Timothy D; Ismail, Abdelbagi M; Pedersen, Ole

    2013-03-01

    Flash floods can submerge paddy field rice (Oryza sativa), with adverse effects on internal aeration, sugar status and survival. Here, we investigated the in situ aeration of roots of rice during complete submergence, and elucidated how underwater photosynthesis and floodwater pO(2) influence root aeration in anoxic soil. In the field, root pO(2) was measured using microelectrodes during 2 d of complete submergence. Leaf gas films that formed on the superhydrophobic leaves were left intact, or experimentally removed, to elucidate their effect on internal aeration. In darkness, root pO(2) declined to very low concentrations (0.24 kPa) and was strongly correlated with floodwater pO(2). In light, root pO(2) was high (14 kPa) and primarily a function of the incident light determining the rates of underwater net photosynthesis. Plants with intact leaf gas films maintained higher underwater net photosynthesis relative to plants without gas films when the submerged shoots were in light. During complete submergence, internal aeration of rice in the field relies on underwater photosynthesis during the day and entry of O(2) from the floodwater during the night. Leaf gas films enhance photosynthesis during submergence leading to improved O(2) production and sugar status, and therefore contribute to the submergence tolerance of rice. © 2012 The Authors. New Phytologist © 2012 New Phytologist Trust.

  16. OCEAN OUTFALLS. II: SPATIAL EVOLUTION OF SUBMERGED WASTEFIELD

    EPA Science Inventory

    Some of the basic features of submerged wastefield formation in stratified currents are reported in this paper. ilution increased with distance from the diffuser in the initial mixing region until it attained a maximum value, which is the initial dilution, after which it remained...

  17. Benthic bacterial diversity in submerged sinkhole ecosystems.

    PubMed

    Nold, Stephen C; Pangborn, Joseph B; Zajack, Heidi A; Kendall, Scott T; Rediske, Richard R; Biddanda, Bopaiah A

    2010-01-01

    Physicochemical characterization, automated ribosomal intergenic spacer analysis (ARISA) community profiling, and 16S rRNA gene sequencing approaches were used to study bacterial communities inhabiting submerged Lake Huron sinkholes inundated with hypoxic, sulfate-rich groundwater. Photosynthetic cyanobacterial mats on the sediment surface were dominated by Phormidium autumnale, while deeper, organically rich sediments contained diverse and active bacterial communities.

  18. Examination of two lowland rice cultivars reveals that gibberellin-dependent early response to submergence is not necessarily mediated by ethylene.

    PubMed

    Dubois, Vincent; Moritz, Thomas; García-Martínez, José L

    2011-01-01

    Using two lowland rice (Oryza sativa L.) cultivars we found that in both cases submerged-induced elongation early after germination depends on gibberellins (GAs). Submergence increases the content of the active GA 1 by enhancing the expression of GA biosynthesis genes, thus facilitating the seedlings to escape from the water and preventing asphyxiation. However, the two cultivars differ in their response to ethylene. The cultivar Senia (short), by contrast to cultivar Bomba (tall), does not elongate after ethylene application, and submerged-induced elongation is not negated by an inhibitor of ethylene perception. Also, while ethylene emanation in Senia is not altered by submergence, Bomba seedlings emanate more ethylene upon de-submergence, associated with enhanced expression of the ethylene biosynthesis gene OsACS5. The cultivar Senia thus allows the possibility of clarifying the role of ethylene and other factors as triggers of GA biosynthesis enhancement in rice seedlings under submergence.

  19. Investigation of a submerged membrane reactor for continuous biomass hydrolysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Malmali, Mohammadmahdi; Stickel, Jonathan; Wickramasinghe, S. Ranil

    Enzymatic hydrolysis of cellulose is one of the most costly steps in the bioconversion of lignocellulosic biomass. Use of a submerged membrane reactor has been investigated for continuous enzymatic hydrolysis of cellulose thus allowing for greater use of the enzyme compared to a batch process. Moreover, the submerged 0.65 μm polyethersulfone microfiltration membrane avoids the need to pump a cellulose slurry through an external loop. Permeate containing glucose is withdrawn at pressures slightly below atmospheric pressure. The membrane rejects cellulose particles and cellulase enzyme bound to cellulose. Our proof-of-concept experiments have been conducted using a modified, commercially available membrane filtrationmore » cell under low fluxes around 75 L/(m2 h). The operating flux is determined by the rate of glucose production. Maximizing the rate of glucose production involves optimizing mixing, reactor holding time, and the time the feed is held in the reactor prior to commencement of membrane filtration and continuous operation. When we maximize glucose production rates it will require that we operate it at low glucose concentration in order to minimize the adverse effects of product inhibition. Consequently practical submerged membrane systems will require a combined sugar concentration step in order to concentrate the product sugar stream prior to fermentation.« less

  20. Responses of bacterial community structure and denitrifying bacteria in biofilm to submerged macrophytes and nitrate

    NASA Astrophysics Data System (ADS)

    Zhang, Songhe; Pang, Si; Wang, Peifang; Wang, Chao; Guo, Chuan; Addo, Felix Gyawu; Li, Yi

    2016-10-01

    Submerged macrophytes play important roles in constructed wetlands and natural water bodies, as these organisms remove nutrients and provide large surfaces for biofilms, which are beneficial for nitrogen removal, particularly from submerged macrophyte-dominated water columns. However, information on the responses of biofilms to submerged macrophytes and nitrogen molecules is limited. In the present study, bacterial community structure and denitrifiers were investigated in biofilms on the leaves of four submerged macrophytes and artificial plants exposed to two nitrate concentrations. The biofilm cells were evenly distributed on artificial plants but appeared in microcolonies on the surfaces of submerged macrophytes. Proteobacteria was the most abundant phylum in all samples, accounting for 27.3-64.8% of the high-quality bacterial reads, followed by Chloroflexi (3.7-25.4%), Firmicutes (3.0-20.1%), Acidobacteria (2.7-15.7%), Actinobacteria (2.2-8.7%), Bacteroidetes (0.5-9.7%), and Verrucomicrobia (2.4-5.2%). Cluster analysis showed that bacterial community structure can be significantly different on macrophytes versus from those on artificial plants. Redundancy analysis showed that electrical conductivity and nitrate concentration were positively correlated with Shannon index and operational taxonomic unit (OTU) richness (log10 transformed) but somewhat negatively correlated with microbial density. The relative abundances of five denitrifying genes were positively correlated with nitrate concentration and electrical conductivity but negatively correlated with dissolved oxygen.

  1. Deep-water kelp refugia as potential hotspots of tropical marine diversity and productivity.

    PubMed

    Graham, Michael H; Kinlan, Brian P; Druehl, Louis D; Garske, Lauren E; Banks, Stuart

    2007-10-16

    Classic marine ecological paradigms view kelp forests as inherently temperate-boreal phenomena replaced by coral reefs in tropical waters. These paradigms hinge on the notion that tropical surface waters are too warm and nutrient-depleted to support kelp productivity and survival. We present a synthetic oceanographic and ecophysiological model that accurately identifies all known kelp populations and, by using the same criteria, predicts the existence of >23,500 km(2) unexplored submerged (30- to 200-m depth) tropical kelp habitats. Predicted tropical kelp habitats were most probable in regions where bathymetry and upwelling resulted in mixed-layer shoaling above the depth of minimum annual irradiance dose for kelp survival. Using model predictions, we discovered extensive new deep-water Eisenia galapagensis populations in the Galápagos that increased in abundance with increasing depth to >60 m, complete with cold-water flora and fauna of temperate affinities. The predictability of deep-water kelp habitat and the discovery of expansive deep-water Galápagos kelp forests validate the extent of deep-water tropical kelp refugia, with potential implications for regional productivity and biodiversity, tropical food web ecology, and understanding of the resilience of tropical marine systems to climate change.

  2. SUBMERGE! bringing the ocean closer to New York City

    NASA Astrophysics Data System (ADS)

    Rosengard, S.; Alexander, H.; Cramer, C.

    2016-02-01

    The annual SUBMERGE!-NYC marine science festival started in October 2014 as an effort to bring the ocean closer to the millions who live and work in the great estuary that is New York City. Organized by the Hudson River Park and the New York Hall of Science, the event brings together oceanography groups, musicians, and food vendors with distinct connections to the coastal ocean and the Hudson River estuary. Oceanography groups can either participate in the festival by giving a science talk during a specific time slot, or presenting science stations to teach concepts through a more interactive, exhibition-type format. Here, we discuss the experiences of graduate students from Woods Hole Oceanographic Institution who created a biological pump-themed science station for the first and second SUBMERGE! festivals (2014 and 2015). We will explore strategies for communicating different processes of the biological pump and its global significance for the oceans and climate. This festival-style setting also presents unique challenges in transferring knowledge, including how to evaluate successful transfer of knowledge. The festival is free and open to the public; the first year drew an audience of 4500, half of which were adults over 30 years old and a third of which were children under 11 years old. Therefore, SUBMERGE! provides an opportunity for graduate students to contribute to the ocean literacy of thousands of New Yorkers as well as a unique experience for graduate students to develop their skills in talking to the public.

  3. Restoring Ecological Function to a Submerged Salt Marsh

    USGS Publications Warehouse

    Stagg, C.L.; Mendelssohn, I.A.

    2010-01-01

    Impacts of global climate change, such as sea level rise and severe drought, have altered the hydrology of coastal salt marshes resulting in submergence and subsequent degradation of ecosystem function. A potential method of rehabilitating these systems is the addition of sediment-slurries to increase marsh surface elevation, thus ameliorating effects of excessive inundation. Although this technique is growing in popularity, the restoration of ecological function after sediment addition has received little attention. To determine if sediment subsidized salt marshes are functionally equivalent to natural marshes, we examined above- and belowground primary production in replicated restored marshes receiving four levels of sediment addition (29-42 cm North American Vertical Datum of 1988 [NAVD 88]) and in degraded and natural ambient marshes (4-22 cm NAVD 88). Moderate intensities of sediment-slurry addition, resulting in elevations at the mid to high intertidal zone (29-36 cm NAVD 88), restored ecological function to degraded salt marshes. Sediment additions significantly decreased flood duration and frequency and increased bulk density, resulting in greater soil drainage and redox potential and significantly lower phytotoxic sulfide concentrations. However, ecological function in the restored salt marsh showed a sediment addition threshold that was characterized by a decline in primary productivity in areas of excessive sediment addition and high elevation (>36 cm NAVD 88). Hence, the addition of intermediate levels of sediment to submerging salt marshes increased marsh surface elevation, ameliorated impacts of prolonged inundation, and increased primary productivity. However, too much sediment resulted in diminished ecological function that was equivalent to the submerged or degraded system. ?? 2010 Society for Ecological Restoration International.

  4. Maintaining network activity in submerged hippocampal slices: importance of oxygen supply.

    PubMed

    Hájos, Norbert; Ellender, Tommas J; Zemankovics, Rita; Mann, Edward O; Exley, Richard; Cragg, Stephanie J; Freund, Tamás F; Paulsen, Ole

    2009-01-01

    Studies in brain slices have provided a wealth of data on the basic features of neurons and synapses. In the intact brain, these properties may be strongly influenced by ongoing network activity. Although physiologically realistic patterns of network activity have been successfully induced in brain slices maintained in interface-type recording chambers, they have been harder to obtain in submerged-type chambers, which offer significant experimental advantages, including fast exchange of pharmacological agents, visually guided patch-clamp recordings, and imaging techniques. Here, we investigated conditions for the emergence of network oscillations in submerged slices prepared from the hippocampus of rats and mice. We found that the local oxygen level is critical for generation and propagation of both spontaneously occurring sharp wave-ripple oscillations and cholinergically induced fast oscillations. We suggest three ways to improve the oxygen supply to slices under submerged conditions: (i) optimizing chamber design for laminar flow of superfusion fluid; (ii) increasing the flow rate of superfusion fluid; and (iii) superfusing both surfaces of the slice. These improvements to the recording conditions enable detailed studies of neurons under more realistic conditions of network activity, which are essential for a better understanding of neuronal network operation.

  5. [Antimicrobial activity of Laetiporus sulphureus strains grown in submerged culture].

    PubMed

    Ershova, E Iu; Tikhonova, O V; Lur'e, L M; Efremenkova, O V; Kamzolkina, O V; Dudnik, Iu V

    2003-01-01

    Cultural conditions for growth and fruit body formation were elaborated to four strains of Laetiporus sulphureus isolated from nature. All strains demonstrated antimicrobial activity against a wide spectrum of gram-positive and gram-negative bacteria during agar and submerged cultivation including methicillin-resistant strain of Staphylococcus aureus (MRSA) and glycopeptide-resistant strain of Leuconostoc mesenteroides. Antifungal activity was not found. The level of antimicrobial activity during submerged cultivation reached maximum after seven days of growth on specific medium with soybean meal and corn liquid; the next four weeks its increasing was not so manifested. Antimicrobial activity correlated with orange pigment secretion and cultural liquid acidification to pH 2.0-2.8 that indicates on acid nature of synthesized products.

  6. Predicting tidal marsh survival or submergence to sea-level rise using Holocene data

    NASA Astrophysics Data System (ADS)

    Horton, B.; Shennan, I.; Bradley, S.; Cahill, N.; Kirwan, M. L.; Kopp, R. E.; Shaw, T.

    2017-12-01

    Rising sea level threatens to permanently submerge tidal marsh environments if they cannot accrete faster than the rate of relative sea-level rise (RSLR). But regional and global model simulations of the future ability of marshes to maintain their elevation with respect to the tidal frame are uncertain. The compilation of empirical data for tidal marsh vulnerability is, therefore, essential to address disparities across these simulations. A hitherto unexplored source of empirical data are Holocene records of tidal marsh evolution. In particular, the marshes of Great Britain have survived and submerged while RSLR varied between -7.7 and 15.2 mm/yr, primarily because of the interplay between global ice-volume changes and regional isostatic processes. Here, we reveal the limits to marsh vulnerability are revealed through the analysis of over 400 reconstructions of tidal marsh submergence and conversion to tidal mud flat or open water from 54 regions in Great Britain during the Holocene. Holocene records indicate a 90% probability of tidal marsh submergence at sites with RSLR exceeding 7.3 mm/yr (95% CI: 6.6-8.6 mm/yr). Although most modern tidal marshes in Great Britain have not yet reached these sea-level rise limits, our empirical data suggest widespread concern over their ability to survive rates of sea-level rise in the 21st century under high emission scenarios. Integrating over the uncertainties in both sea-level rise predictions and the response of tidal marshes to sea-level rise, all of Great Britain has a >80% probability of marsh submergence under RCP 8.5 by 2100, with areas of south and eastern England, where the rate of RSLR is increased by glacio-isostatic subsidence, achieving this probability by 2040.

  7. The role of submerged trees in the early development of fishes in a Neotropical reservoir.

    PubMed

    Gogola, T M; Daga, P S; Gubiani, É A; da Silva, P L R; Sanches, P V

    2016-07-01

    It was hypothesized that the structural heterogeneity provided by submerged trees positively favours the spatial distribution of fish abundance at early stages of development in an area under the influence of a Neotropical reservoir in the Paraná River basin. The distribution at early stages of development of the most abundant species was evaluated. To remove any possible confounding effect related to local environmental variables, changes in these were also evaluated. Sampling was carried out at sites with and without submerged trees. Among all individuals sampled, 96·1% were classified as larvae and 3·9% as juveniles. The area without submerged trees showed higher total abundance, but there were spatial differences in the distribution of early stage fishes. From the moment the larvae are able to swim actively, they search for sites with a complex structure. The results show that reaches with submerged trees play an important role in the early development of fishes in reservoirs, and, hence, the preservation of those trees is essential to maintain biodiversity in reservoirs. © 2016 The Fisheries Society of the British Isles.

  8. Leaf gas films delay salt entry and enhance underwater photosynthesis and internal aeration of Melilotus siculus submerged in saline water.

    PubMed

    Teakle, Natasha Lea; Colmer, Timothy David; Pedersen, Ole

    2014-10-01

    A combination of flooding and salinity is detrimental to most plants. We studied tolerance of complete submergence in saline water for Melilotus siculus, an annual legume with superhydrophobic leaf surfaces that retain gas films when under water. M. siculus survived complete submergence of 1 week at low salinity (up to 50 mol m(-3) NaCl), but did not recover following de-submergence from 100 mol m(-3) NaCl. The leaf gas films protected against direct salt ingress into the leaves when submerged in saline water, enabling underwater photosynthesis even after 3 d of complete submergence. By contrast, leaves with the gas films experimentally removed suffered from substantial Na(+) and Cl(-) intrusion and lost the capacity for underwater photosynthesis. Similarly, plants in saline water and without gas films lost more K(+) than those with intact gas films. This study has demonstrated that leaf gas films reduce Na(+) and Cl(-) ingress into leaves when submerged by saline water - the thin gas layer physically separates the floodwater from the leaf surface. This feature aids survival of plants exposed to short-term saline submergence, as well as the previously recognized beneficial effects of gas exchange under water. © 2014 John Wiley & Sons Ltd.

  9. Leaf gas films contribute to rice (Oryza sativa) submergence tolerance during saline floods.

    PubMed

    Herzog, Max; Konnerup, Dennis; Pedersen, Ole; Winkel, Anders; Colmer, Timothy David

    2018-05-01

    Floods and salinization of agricultural land adversely impact global rice production. We investigated whether gas films on leaves of submerged rice delay salt entry during saline submergence. Two-week-old plants with leaf gas films (+GF) or with gas films experimentally removed (-GF) were submerged in artificial floodwater with 0 or 50 mm NaCl for up to 16 d. Gas films were present >9 d on GF plants after which gas films were diminished. Tissue ion analysis (Na + , Cl - and K + ) showed that gas films caused some delay of Na + entry, as leaf Na + concentration was 36-42% higher in -GF leaves than +GF leaves on days 1-5. However, significant net uptakes of Na + and Cl - , and K + net loss, occurred despite the presence of gas films, indicating the likely presence of some leaf-to-floodwater contact, so that the gas layer must not have completely separated the leaf surfaces from the water. Natural loss and removal of gas films resulted in severe declines in growth, underwater photosynthesis, chlorophyll a and tissue porosity. Submergence was more detrimental to leaf P N and growth than the additional effect of 50 mm NaCl, as salt did not significantly affect underwater P N at 200 μm CO 2 nor growth. © 2016 John Wiley & Sons Ltd.

  10. Watershed and Hydrodynamic Modeling for Evaluating the Impact of Land Use Change on Submerged Aquatic Vegetation and Seagrasses in Mobile Bay

    DTIC Science & Technology

    2010-06-01

    35805 3 Pacific Northwest National Laboratory 1529 W. Sequim Bay Rd. Sequim , WA 98382 4 University of South Carolina Columbia, SC 5 Tetra...Watershed and Hydrodynamic Modeling for Evaluating the Impact of Land Use Change on Submerged Aquatic Vegetation and Seagrasses in Mobile Bay ...land use change. Mobile Bay , AL is a designated pilot region of the Gulf of Mexico Alliance (GOMA) and is the focus area of many current NASA and

  11. Comparison of the role of gibberellins and ethylene in response to submergence of two lowland rice cultivars, Senia and Bomba.

    PubMed

    Dubois, Vincent; Moritz, Thomas; García-Martínez, José L

    2011-02-15

    We examined the gibberellin (GA) and ethylene regulation of submergence-induced elongation in seedlings of the submergence-tolerant lowland rice (Oryza sativa L.) cvs Senia and Bomba. Elongation was enhanced after germination to facilitate water escape and reach air. We found that submergence-induced elongation depends on GA because it was counteracted by paclobutrazol (an inhibitor of GA biosynthesis), an effect that was negated by GA(3). Moreover, in the cv Senia, submergence increased the content of active GA(1) and its immediate precursors (GA(53), GA(19) and GA(20)) by enhancing expression of several GA biosynthesis genes (OsGA20ox1 and -2, and OsGA3ox2), but not by decreasing expression of several OsGA2ox (GA inactivating genes). Senia seedlings, in contrast to Bomba seedlings, did not elongate in response to ethylene or 1-aminocyclopropane-1-carboxylic-acid (ACC; an ethylene precursor) application, and submergence-induced elongation was not reduced in the presence of 1-methylcyclopropene (1-MCP; an ethylene perception inhibitor). Ethylene emanation was similar in Senia seedlings grown in air and in submerged-grown seedlings following de-submergence, while it increased in Bomba. The expression of ethylene biosynthesis genes (OsACS1, -2 and -3, and OsACO1) was not affected in Senia, but expression of OsACS5 was rapidly enhanced in Bomba upon submergence. Our results support the conclusion that submergence elongation enhancement of lowland rice is due to alteration of GA metabolism leading to an increase in active GA (GA(1)) content. Interestingly, in the cv Senia, in contrast to cv Bomba, this was triggered through an ethylene-independent mechanism. Copyright © 2010 Elsevier GmbH. All rights reserved.

  12. Supporting Calculations For Submerged Bed Scrubber Condensate Disposal Preconceptual Study

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pajunen, A. J.; Tedeschi, A. R.

    This document provides supporting calculations for the preparation of the Submerged Bed Scrubber Condensate Disposal Preconceptual Study report The supporting calculations include equipment sizing, Hazard Category determination, and LAW Melter Decontamination Factor Adjustments.

  13. Mapping of submerged vegetation using remote sensing technology

    NASA Technical Reports Server (NTRS)

    Savastano, K. J.; Faller, K. H.; Mcfadin, L. W.; Holley, H.

    1981-01-01

    Techniques for mapping submerged sea grasses using aircraft supported remote sensors are described. The 21 channel solid state array spectroradiometer was successfully used as a remote sensor in the experiment in that the system operated without problem and obtained data. The environmental conditions of clear water, bright sandy bottom and monospecific vegetation (Thalassia) were ideal.

  14. Implementation of Submerged Arc Welding Training. Final Report.

    ERIC Educational Resources Information Center

    Bowick, Earl; Todd, John

    A unit on submerged arc welding (SAW) was developed and integrated into the welding program at Seattle Central Community College (Washington) during the period December 1983 through May 1984. During this time, 10 major users of SAW in the area were contacted and mailed questionnaires. Follow up consisted of telephone calls and personal contact as…

  15. Deep Venous Procedures Performed in the National Health Service in England between 2005 and 2015.

    PubMed

    Lim, C S; Shalhoub, J; Davies, A H

    2017-10-01

    Recent advances in imaging technology and endovenous interventions have revolutionised the management of specific groups of patients with deep venous pathology. This study aimed to examine data published by Hospital Episode Statistics (HES) to assess trends in the number of endovascular and open surgical deep venous procedures performed in National Health Service (NHS) hospitals in England between 2005 and 2015. The main diagnosis of deep venous thrombosis (DVT), and total number of primary open and percutaneous procedures for deep venous pathology for patients admitted to the NHS hospitals in England from 2005 to 2015 were retrieved from the HES database and analysed. An overall declining trend in the annual number of admissions for a primary diagnosis of DVT was observed (linear regression r 2  = 0.9, p < .0001). The number of open surgical procedures for removal of thrombus remained largely unchanged (range 26-70); the frequency of percutaneous procedures increased steadily over the study period (range 0-311). The number of open surgical procedures relating to the vena cava fell between 2005 and 2009, and remained around 50 per year thereafter. Annual numbers of cases of deep venous bypass (range 17-33) and venous valve surgery (range 8-47) remained similar in trend over this period. The number of vena cava stent (range 0-405), other venous stent (range 0-316), and percutaneous venoplasty (range 0-972) procedures increased over the first 5 years of the study period. There is an increasing trend in relation to endovenous procedures but not open surgery, being carried out for deep venous pathology in the last decade in NHS hospitals in England. Despite a number of limitations with HES, the increase in the number of endovenous procedures shown is likely to have significant implications for the provision of care and healthcare resources for patients with deep venous pathology. Copyright © 2017 European Society for Vascular Surgery. Published by Elsevier Ltd. All

  16. Coordinated motility of cyanobacteria favor mat formation, photosynthesis and carbon burial in low-oxygen, high-sulfur shallow sinkholes of Lake Huron; whereas deep-water aphotic sinkholes are analogs of deep-sea seep and vent ecosystems

    NASA Astrophysics Data System (ADS)

    Biddanda, B. A.; McMillan, A. C.; Long, S. A.; Snider, M. J.; Weinke, A. D.; Dick, G.; Ruberg, S. A.

    2016-02-01

    Microbial life in submerged sinkhole ecosystems of the Laurentian Great Lakes is relatively understudied in comparison to seeps and vents of the deep-sea. We studied the filamentous benthic mat-forming cyanobacteria consisting primarily of Oscillatoria-like cells growing under low-light, low-oxygen and high-sulfur conditions in Lake Huron's submerged sinkholes using in situ observations, in vitro measurements and time-lapse microscopy. Gliding movement of the cyanobacterial trichomes revealed individual as well as group-coordinated motility. When placed in a petri dish and dispersed in ground water from the sinkhole, filaments re-aggregated into defined colonies within minutes. Measured speed of individual filaments ranged from 50 µm minute-1 or 15 body lengths minute-1 to 215 µm minute-1 or 70 body lengths minute-1 - rates that are rapid relative to non-flagellated/ciliated microbes. Filaments exhibited precise and coordinated positive phototaxis towards pinpoints of light and congregated under the light of foil cutouts. Such light-responsive clusters showed an increase in photosynthetic yield - suggesting phototactic motility aids in light acquisition as well as photosynthesis. Pebbles and pieces of broken shells placed upon the mat in intact sediemnt cores were quickly covered by vertically motile filaments within hours and became fully buried in the anoxic sediments over 3-4 diurnal cycles - likely facilitating the preservation of falling plankton debris. Coordinated horizontal and vertical filament motility optimize mat cohesion and dynamics, photosynthetic efficiency and sedimentary carbon burial in modern-day sinkhole habitats where life operates across sharp redox gradients. Analogous cyanobacterial motility in the shallow seas during Earth's early history, may have played a key role in the oxygenation of the planet by optimizing photosynthesis while favoring carbon burial. We are now eagerly mapping and exploring life in deep-water aphotic sinkholes of

  17. 78 FR 16296 - Record of Decision for the Coral Reef Restoration Plan, Biscayne National Park, FL

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-14

    ...] Record of Decision for the Coral Reef Restoration Plan, Biscayne National Park, FL AGENCY: National Park... Record of Decision (ROD) for the Coral Reef Restoration Plan (Plan) for Biscayne National Park, Florida... Biscayne National Park, causing injuries to submerged resources. The goal of coral reef restoration actions...

  18. Mycelium and polysaccharide production of Agaricus blazei Murrill by submerged fermentation.

    PubMed

    Lin, Jr-Hui; Yang, Shang-Shyng

    2006-04-01

    Over the last decade, Agaricus blazei Murrill has been studied and developed as a novel functional food in Japan, Korea, China, and Taiwan. Due to the low yields, the fruiting bodies of A. blazei Murrill are relatively expensive, and a cheap and stable source of A. blazei Murrill mycelium for commercial purposes is highly desirable. Culture media and conditions were investigated with a view to reducing the cost and improving the mycelium and polysaccharide production of A. blazei Murrill by submerged fermentation. Thirty six isolates of A. blazei Murrill were isolated from 22 fruiting bodies produced in Taiwan, and 16 of them could be successfully cultivated on mannitol-egg yolk-polymyxin medium. The isolates were identified by species-specific polymerase chain reaction (PCR) and optimized for the culture media and conditions by submerged fermentation for mycelium and polysaccharide production. Some properties of polysaccharide extract were also investigated. All of the PCR products with species-specific primers showed high identity and matched the internal transcribed spacer 1 sequences of A. blazei Murrill. The phylogenic tree of A. blazei Murrill isolates generated from random amplified polymorphic DNAs arranged all samples into 3 groups and 2 independent cases. The optimal culture media of mycelium production in submerged fermentation were 5% malt extract, 0.1% yeast extract, and 0.5% peptone at pH 6.0, while the optimal culture conditions were 200 mL medium in 500 mL Hinton flask, shaking at 90 rpm for 3 days and then shifting to 105 rpm for 5 days at 27 degrees C. Each liter of A. blazei Murrill M72 yielded 10.83 +/- 0.24 g dried mycelia weight and each liter of A. blazei Murrill M152 produced 0.251 +/- 0.004 g crude polysaccharide (3.03 +/- 0.05% of dried mycelia weight). Crude polysaccharide of A. blazei Murrill M162 contained 82.27-99.14% of total sugar and less than 1.63% of protein; it had 4 major molecular weight components (274.1, 32.7, 7.5, and 2.1 k

  19. Allelic variants of OsSUB1A cause differential expression of transcription factor genes in response to submergence in rice.

    PubMed

    Sharma, Niharika; Dang, Trang Minh; Singh, Namrata; Ruzicic, Slobodan; Mueller-Roeber, Bernd; Baumann, Ute; Heuer, Sigrid

    2018-01-08

    Flooding during seasonal monsoons affects millions of hectares of rice-cultivated areas across Asia. Submerged rice plants die within a week due to lack of oxygen, light and excessive elongation growth to escape the water. Submergence tolerance was first reported in an aus-type rice landrace, FR13A, and the ethylene-responsive transcription factor (TF) gene SUB1A-1 was identified as the major tolerance gene. Intolerant rice varieties generally lack the SUB1A gene but some intermediate tolerant varieties, such as IR64, carry the allelic variant SUB1A-2. Differential effects of the two alleles have so far not been addressed. As a first step, we have therefore quantified and compared the expression of nearly 2500 rice TF genes between IR64 and its derived tolerant near isogenic line IR64-Sub1, which carries the SUB1A-1 allele. Gene expression was studied in internodes, where the main difference in expression between the two alleles was previously shown. Nineteen and twenty-six TF genes were identified that responded to submergence in IR64 and IR64-Sub1, respectively. Only one gene was found to be submergence-responsive in both, suggesting different regulatory pathways under submergence in the two genotypes. These differentially expressed genes (DEGs) mainly included MYB, NAC, TIFY and Zn-finger TFs, and most genes were downregulated upon submergence. In IR64, but not in IR64-Sub1, SUB1B and SUB1C, which are also present in the Sub1 locus, were identified as submergence responsive. Four TFs were not submergence responsive but exhibited constitutive, genotype-specific differential expression. Most of the identified submergence responsive DEGs are associated with regulatory hormonal pathways, i.e. gibberellins (GA), abscisic acid (ABA), and jasmonic acid (JA), apart from ethylene. An in-silico promoter analysis of the two genotypes revealed the presence of allele-specific single nucleotide polymorphisms, giving rise to ABRE, DRE/CRT, CARE and Site II cis-elements, which

  20. Proteomic analysis of extracellular proteins from Aspergillus oryzae grown under submerged and solid-state culture conditions.

    PubMed

    Oda, Ken; Kakizono, Dararat; Yamada, Osamu; Iefuji, Haruyuki; Akita, Osamu; Iwashita, Kazuhiro

    2006-05-01

    Filamentous fungi are widely used for the production of homologous and heterologous proteins. Recently, there has been increasing interest in Aspergillus oryzae because of its ability to produce heterologous proteins in solid-state culture. To provide an overview of protein secretion by A. oryzae in solid-state culture, we carried out a comparative proteome analysis of extracellular proteins in solid-state and submerged (liquid) cultures. Extracellular proteins prepared from both cultures sequentially from 0 to 40 h were subjected to two-dimensional electrophoresis, and protein spots at 40 h were identified by peptide mass fingerprinting using matrix-assisted laser desorption ionization-time-of-flight mass spectrometry. We also attempted to identify cell wall-bound proteins of the submerged culture. We analyzed 85 spots from the solid-state culture and 110 spots from the submerged culture. We identified a total of 29 proteins, which were classified into 4 groups. Group 1 consisted of extracellular proteins specifically produced in the solid-state growth condition, such as glucoamylase B and alanyl dipeptidyl peptidase. Group 2 consisted of extracellular proteins specifically produced in the submerged condition, such as glucoamylase A (GlaA) and xylanase G2 (XynG2). Group 3 consisted of proteins produced in both conditions, such as xylanase G1. Group 4 consisted of proteins that were secreted to the medium in the solid-state growth condition but trapped in the cell wall in the submerged condition, such as alpha-amylase (TAA) and beta-glucosidase (Bgl). A Northern analysis of seven genes from the four groups suggested that the secretion of TAA and Bgl was regulated by trapping these proteins in the cell wall in submerged culture and that secretion of GlaA and XynG2 was regulated at the posttranscriptional level in the solid-state culture.

  1. Proteomic Analysis of Extracellular Proteins from Aspergillus oryzae Grown under Submerged and Solid-State Culture Conditions

    PubMed Central

    Oda, Ken; Kakizono, Dararat; Yamada, Osamu; Iefuji, Haruyuki; Akita, Osamu; Iwashita, Kazuhiro

    2006-01-01

    Filamentous fungi are widely used for the production of homologous and heterologous proteins. Recently, there has been increasing interest in Aspergillus oryzae because of its ability to produce heterologous proteins in solid-state culture. To provide an overview of protein secretion by A. oryzae in solid-state culture, we carried out a comparative proteome analysis of extracellular proteins in solid-state and submerged (liquid) cultures. Extracellular proteins prepared from both cultures sequentially from 0 to 40 h were subjected to two-dimensional electrophoresis, and protein spots at 40 h were identified by peptide mass fingerprinting using matrix-assisted laser desorption ionization-time-of-flight mass spectrometry. We also attempted to identify cell wall-bound proteins of the submerged culture. We analyzed 85 spots from the solid-state culture and 110 spots from the submerged culture. We identified a total of 29 proteins, which were classified into 4 groups. Group 1 consisted of extracellular proteins specifically produced in the solid-state growth condition, such as glucoamylase B and alanyl dipeptidyl peptidase. Group 2 consisted of extracellular proteins specifically produced in the submerged condition, such as glucoamylase A (GlaA) and xylanase G2 (XynG2). Group 3 consisted of proteins produced in both conditions, such as xylanase G1. Group 4 consisted of proteins that were secreted to the medium in the solid-state growth condition but trapped in the cell wall in the submerged condition, such as α-amylase (TAA) and β-glucosidase (Bgl). A Northern analysis of seven genes from the four groups suggested that the secretion of TAA and Bgl was regulated by trapping these proteins in the cell wall in submerged culture and that secretion of GlaA and XynG2 was regulated at the posttranscriptional level in the solid-state culture. PMID:16672490

  2. Examination of two lowland rice cultivars reveals that gibberellin-dependent early response to submergence is not necessarily mediated by ethylene

    PubMed Central

    Dubois, Vincent; Moritz, Thomas

    2011-01-01

    Using two lowland rice (Oryza sativa L.) cultivars we found that in both cases submerged-induced elongation early after germination depends on gibberellins (GAs). Submergence increases the content of the active GA1 by enhancing the expression of GA biosynthesis genes, thus facilitating the seedlings to escape from the water and preventing asphyxiation. However, the two cultivars differ in their response to ethylene. The cultivar Senia (short), by contrast to cultivar Bomba (tall), does not elongate after ethylene application, and submerged-induced elongation is not negated by an inhibitor of ethylene perception. Also, while ethylene emanation in Senia is not altered by submergence, Bomba seedlings emanate more ethylene upon desubmergence, associated with enhanced expression of the ethylene biosynthesis gene OsACS5. The cultivar Senia thus allows the possibility of clarifying the role of ethylene and other factors as triggers of GA biosynthesis enhancement in rice seedlings under submergence. PMID:21224726

  3. Improved, Low-Stress Economical Submerged Pipeline

    NASA Technical Reports Server (NTRS)

    Jones, Jack A.; Chao, Yi

    2011-01-01

    A preliminary study has shown that the use of a high-strength composite fiber cloth material may greatly reduce fabrication and deployment costs of a subsea offshore pipeline. The problem is to develop an inexpensive submerged pipeline that can safely and economically transport large quantities of fresh water, oil, and natural gas underwater for long distances. Above-water pipelines are often not feasible due to safety, cost, and environmental problems, and present, fixed-wall, submerged pipelines are often very expensive. The solution is to have a submerged, compliant-walled tube that when filled, is lighter than the surrounding medium. Some examples include compliant tubes for transporting fresh water under the ocean, for transporting crude oil underneath salt or fresh water, and for transporting high-pressure natural gas from offshore to onshore. In each case, the fluid transported is lighter than its surrounding fluid, and thus the flexible tube will tend to float. The tube should be ballasted to the ocean floor so as to limit the motion of the tube in the horizontal and vertical directions. The tube should be placed below 100-m depth to minimize biofouling and turbulence from surface storms. The tube may also have periodic pumps to maintain flow without over-pressurizing, or it can have a single pump at the beginning. The tube may have periodic valves that allow sections of the tube to be repaired or maintained. Some examples of tube materials that may be particularly suited for these applications are non-porous composite tubes made of high-performance fibers such as Kevlar, Spectra, PBO, Aramid, carbon fibers, or high-strength glass. Above-ground pipes for transporting water, oil, and natural gas have typically been fabricated from fiber-reinforced plastic or from more costly high-strength steel. Also, previous suggested subsea pipeline designs have only included heavy fixed-wall pipes that can be very expensive initially, and can be difficult and expensive

  4. Hydraulic resistance of submerged flexible vegetation

    NASA Astrophysics Data System (ADS)

    Stephan, Ursula; Gutknecht, Dieter

    2002-12-01

    The main research objective consisted in analysing the influence of roughness caused by aquatic vegetation (av), in particular submerged macrophytes, on the overall flow field. These plants are highly flexible and behave differently depending on the flow situation. They also react substantially to the flow field and thus, the roughness becomes variable and dynamic. Conventional flow formulas, such as the Manning or the Strickler formula, are one-dimensional and based on integral flow parameters. They are not suitable for quantifying the roughness of av, because the flow is complex and more dimensional due to the variable behaviour of the plants. Therefore, the present investigation concentrates on the definition of a characteristic hydraulic roughness parameter to quantify the resistance of av. Within this investigation laboratory experiments were carried out with three different types of av, chosen with respect to varying plant structures as well as stem lengths. Velocity measurements above these plants were conducted to determine the relationship between the hydraulic roughness and the deflected plant height. The deflected plant height is used as the geometric roughness parameter, whereas the equivalent sand roughness based on the universal logarithmic law modified by Nikuradse was used as hydraulic roughness parameter. The influence of relative submergence on the hydraulic roughness was also analysed. The analysis of the velocity measurements illustrates that equivalent sand roughness and zero plane displacement of the logarithmic law are correlated to the deflected plant height and are equally to this height.

  5. Production and Characterization of Lipases by Two New Isolates of Aspergillus through Solid-State and Submerged Fermentation

    PubMed Central

    Colla, Luciane Maria; Ficanha, Aline M. M.; Rizzardi, Juliana; Bertolin, Telma Elita; Reinehr, Christian Oliveira; Costa, Jorge Alberto Vieira

    2015-01-01

    Due to the numerous applications of lipases in industry, there is a need to study their characteristics, because lipases obtained from different sources may present different properties. The aim of this work was to accomplish the partial characterization of lipases obtained through submerged fermentation and solid-state fermentation by two species of Aspergillus. Fungal strains were isolated from a diesel-contaminated soil and selected as good lipases producers. Lipases obtained through submerged fermentation presented optimal activities at 37°C and pH 7.2 and those obtained through solid-state fermentation at 35°C and pH 6.0. The enzymes produced by submerged fermentation were more temperature-stable than those obtained by solid-state fermentation, presenting 72% of residual activity after one hour of exposition at 90°C. Lipases obtained through submerged fermentation had 80% of stability in acidic pH and those obtained through solid-state fermentation had stability greater than 60% in alkaline pH. PMID:26180809

  6. Comparison of solid-state and submerged-state fermentation for the bioprocessing of switchgrass to ethanol and acetate by Clostridium phytofermentans.

    PubMed

    Jain, Abhiney; Morlok, Charles K; Henson, J Michael

    2013-01-01

    The conversion of sustainable energy crops using microbiological fermentation to biofuels and bioproducts typically uses submerged-state processes. Alternatively, solid-state fermentation processes have several advantages when compared to the typical submerged-state processes. This study compares the use of solid-state versus submerged-state fermentation using the mesophilic anaerobic bacterium Clostridium phytofermentans in the conversion of switchgrass to the end products of ethanol, acetate, and hydrogen. A shift in the ratio of metabolic products towards more acetate and hydrogen production than ethanol production was observed when C. phytofermentans was grown under solid-state conditions as compared to submerged-state conditions. Results indicated that the end product concentrations (in millimolar) obtained using solid-state fermentation were higher than using submerged-state fermentation. In contrast, the total fermentation products (in weight of product per weight of carbohydrates consumed) and switchgrass conversion were higher for submerged-state fermentation. The conversion of xylan was greater than glucan conversion under both fermentation conditions. An initial pH of 7 and moisture content of 80 % resulted in maximum end products formation. Scanning electron microscopy study showed the presence of biofilm formed by C. phytofermentans growing on switchgrass under submerged-state fermentation whereas bacterial cells attached to surface and no apparent biofilm was observed when grown under solid-state fermentation. To our knowledge, this is the first study reporting consolidated bioprocessing of a lignocellulosic substrate by a mesophilic anaerobic bacterium under solid-state fermentation conditions.

  7. Benthic Bacterial Diversity in Submerged Sinkhole Ecosystems▿ †

    PubMed Central

    Nold, Stephen C.; Pangborn, Joseph B.; Zajack, Heidi A.; Kendall, Scott T.; Rediske, Richard R.; Biddanda, Bopaiah A.

    2010-01-01

    Physicochemical characterization, automated ribosomal intergenic spacer analysis (ARISA) community profiling, and 16S rRNA gene sequencing approaches were used to study bacterial communities inhabiting submerged Lake Huron sinkholes inundated with hypoxic, sulfate-rich groundwater. Photosynthetic cyanobacterial mats on the sediment surface were dominated by Phormidium autumnale, while deeper, organically rich sediments contained diverse and active bacterial communities. PMID:19880643

  8. The mechanism of improved aeration due to gas films on leaves of submerged rice.

    PubMed

    Verboven, Pieter; Pedersen, Ole; Ho, Quang Tri; Nicolai, Bart M; Colmer, Timothy D

    2014-10-01

    Some terrestrial wetland plants, such as rice, have super-hydrophobic leaf surfaces which retain a gas film when submerged. O2 movement through the diffusive boundary layer (DBL) of floodwater, gas film and stomata into leaf mesophyll was explored by means of a reaction-diffusion model that was solved in a three-dimensional leaf anatomy model. The anatomy and dark respiration of leaves of rice (Oryza sativa L.) were measured and used to compute O2 fluxes and partial pressure of O2 (pO2 ) in the DBL, gas film and leaf when submerged. The effects of floodwater pO2 , DBL thickness, cuticle permeability, presence of gas film and stomatal opening were explored. Under O2 -limiting conditions of the bulk water (pO2  < 10 kPa), the gas film significantly increases the O2 flux into submerged leaves regardless of whether stomata are fully or partly open. With a gas film, tissue pO2 substantially increases, even for the slightest stomatal opening, but not when stomata are completely closed. The effect of gas films increases with decreasing cuticle permeability. O2 flux and tissue pO2 decrease with increasing DBL thickness. The present modelling analysis provides a mechanistic understanding of how leaf gas films facilitate O2 entry into submerged plants. © 2014 John Wiley & Sons Ltd.

  9. The Effect of Stem- and Canopy-Scale Turbulence on Sediment Dynamics within Submerged Vegetation.

    NASA Astrophysics Data System (ADS)

    Tinoco, R. O.; San Juan Blanco, J. E.; Prada, A. F.

    2017-12-01

    Stem- and canopy-scale turbulence generated by submerged patches of vegetation plays a paramount role on sediment transport within aquatic ecosystems such as wetlands, marshes, mangrove forests, and coastal regions, as dense patches dampen velocities and mean bed stresses within the plants, while also increasing turbulence intensity through stem-scale wakes and canopy-scale eddies. To explore the interactions between such processes, laboratory experiments are conducted using rigid cylinders placed in a staggered configuration as vegetation elements, embedded on a non-cohesive sediment bed in a racetrack flume. Quantitative imaging is used to characterize the flow field and the associated suspended sediment concentration throughout the water column at different submergence ratios, defined as the ratio between water depth, H, and plant height, h, to investigate the role of canopy-scale eddies formed at the top of the canopy, and their interaction with near-bed flow structures, on sediment dynamics. Turbulent kinetic energy, turbulent intensity, and Reynolds stresses are quantified within and above the array to clearly identify the contributions from bed generated turbulence and vegetation generated turbulence, at both stem- and canopy-scale, as submergence ratio increases from emergent, H/h=1, to fully submerged, H/h=5, conditions. The experimental results are compared with transport models to highlight the need for a multi-scale approach to represent flow-vegetation-sediment interactions.

  10. Field calibration of submerged sluice gates in irrigation canals

    USDA-ARS?s Scientific Manuscript database

    Four rectangular sluice gates were calibrated for submerged-flow conditions using nearly 16,000 field-measured data points on Canal B of the B-XII irrigation scheme in Lebrija, Spain. Water depth and gate opening values were measured using acoustic sensors at each of the gate structures, and the dat...

  11. Excitation of ship waves by a submerged object: New solution to the classical problem

    NASA Astrophysics Data System (ADS)

    Arzhannikov, A. V.; Kotelnikov, I. A.

    2016-08-01

    We have proposed a new method for solving the problem of ship waves excited on the surface of a nonviscous liquid by a submerged object that moves at a variable speed. As a first application of this method, we have obtained a new solution to the classic problem of ship waves generated by a submerged ball that moves rectilinearly with constant velocity parallel to the equilibrium surface of the liquid. For this example, we have derived asymptotic expressions describing the vertical displacement of the liquid surface in the limit of small and large values of the Froude number. The exact solution is presented in the form of two terms, each of which is reduced to one-dimensional integrals. One term describes the "Bernoulli hump" and another term the "Kelvin wedge." As a second example, we considered vertical oscillation of the submerged ball. In this case, the solution leads to the calculation of one-dimensional integral and describes surface waves propagating from the epicenter above the ball.

  12. Excitation of ship waves by a submerged object: New solution to the classical problem.

    PubMed

    Arzhannikov, A V; Kotelnikov, I A

    2016-08-01

    We have proposed a new method for solving the problem of ship waves excited on the surface of a nonviscous liquid by a submerged object that moves at a variable speed. As a first application of this method, we have obtained a new solution to the classic problem of ship waves generated by a submerged ball that moves rectilinearly with constant velocity parallel to the equilibrium surface of the liquid. For this example, we have derived asymptotic expressions describing the vertical displacement of the liquid surface in the limit of small and large values of the Froude number. The exact solution is presented in the form of two terms, each of which is reduced to one-dimensional integrals. One term describes the "Bernoulli hump" and another term the "Kelvin wedge." As a second example, we considered vertical oscillation of the submerged ball. In this case, the solution leads to the calculation of one-dimensional integral and describes surface waves propagating from the epicenter above the ball.

  13. GID1 modulates stomatal response and submergence tolerance involving abscisic acid and gibberellic acid signaling in rice.

    PubMed

    Du, Hao; Chang, Yu; Huang, Fei; Xiong, Lizhong

    2015-11-01

    Plant responses to abiotic stresses are coordinated by arrays of growth and developmental programs. Gibberellic acid (GA) and abscisic acid (ABA) play critical roles in the developmental programs and environmental responses, respectively, through complex signaling and metabolism networks. However, crosstalk between the two phytohormones in stress responses remains largely unknown. In this study, we report that GIBBERELLIN-INSENSITIVE DWARF 1 (GID1), a soluble receptor for GA, regulates stomatal development and patterning in rice (Oryza sativa L.). The gid1 mutant showed impaired biosynthesis of endogenous ABA under drought stress conditions, but it exhibited enhanced sensitivity to exogenous ABA. Scanning electron microscope and infrared thermal image analysis indicated an increase in the stomatal conductance in the gid1 mutant under drought conditions. Interestingly, the gid1 mutant had increased levels of chlorophyll and carbohydrates under submergence conditions, and showed enhanced reactive oxygen species (ROS)-scavenging ability and submergence tolerance compared with the wild-type. Further analyses suggested that the function of GID1 in submergence responses is partially dependent on ABA, and GA signaling by GID1 is involved in submergence tolerance by modulating carbohydrate consumption. Taken together, these findings suggest GID1 plays distinct roles in stomatal response and submergence tolerance through both the ABA and GA signaling pathways in rice. © 2014 Institute of Botany, Chinese Academy of Sciences.

  14. Induction of kranz anatomy and C4-like biochemical characteristics in a submerged amphibious plant by abscisic acid

    PubMed Central

    Ueno, O

    1998-01-01

    The amphibious leafless sedge Eleocharis vivipara develops C4-like traits as well as Kranz anatomy under terrestrial conditions, but it develops C3-like traits without Kranz anatomy under submerged conditions. When submerged plants are exposed to aerial conditions, they rapidly produce new photosynthetic tissues with C4-like traits. In this study, experiments were performed to determine whether abscisic acid (ABA), a plant stress hormone, could induce the formation of photosynthetic tissues with Kranz anatomy and C4-like biochemical traits under water in the submerged form. When the submerged plants were grown in water containing 5 &mgr;M ABA, they developed new photosynthetic tissues with Kranz anatomy, forming well-developed Kranz (bundle sheath) cells that contained many organelles. The ABA-induced tissues accumulated large amounts of phosphoenolpyruvate carboxylase, pyruvate orthophosphate dikinase, and NAD-malic enzyme at the appropriate cellular sites. The tissues had 3.4 to 3.8 times more C4 enzyme activity than did tissues of the untreated submerged plants. Carbon-14 pulse and carbon-12 chase experiments revealed that the ABA-induced tissues fixed higher amounts of carbon-14 into C4 compounds and lower amounts of carbon-14 into C3 compounds as initial products than did the submerged plants and that they exhibited a C4-like pattern of carbon fixation under aqueous conditions of low carbon, indicating enhanced C4 capacity in the tissues. This report provides an example of the hormonal control of the differentiation of the structural and functional traits required for the C4 pathway. PMID:9548983

  15. Surviving floods: leaf gas films improve O₂ and CO₂ exchange, root aeration, and growth of completely submerged rice.

    PubMed

    Pedersen, Ole; Rich, Sarah Meghan; Colmer, Timothy David

    2009-04-01

    When completely submerged, the leaves of some species retain a surface gas film. Leaf gas films on submerged plants have recently been termed 'plant plastrons', analogous with the plastrons of aquatic insects. In aquatic insects, surface gas layers (i.e. plastrons) enlarge the gas-water interface to promote O₂ uptake when under water; however, the function of leaf gas films has rarely been considered. The present study demonstrates that gas films on leaves of completely submerged rice facilitate entry of O₂ from floodwaters when in darkness and CO₂ entry when in light. O₂ microprofiles showed that the improved gas exchange was not caused by differences in diffusive boundary layers adjacent to submerged leaves with or without gas films; instead, reduced resistance to gas exchange was probably due to the enlarged water-gas interface (cf. aquatic insects). When gas films were removed artificially, underwater net photosynthesis declined to only 20% of the rate with gas films present, such that, after 7 days of complete submergence, tissue sugar levels declined, and both shoot and root growth were reduced. Internal aeration of roots in anoxic medium, when shoots were in aerobic floodwater in darkness or when in light, was improved considerably when leaf gas films were present. Thus, leaf gas films contribute to the submergence tolerance of rice, in addition to those traits already recognized, such as the shoot-elongation response, aerenchyma and metabolic adjustments to O₂ deficiency and oxidative stress. © 2009 The Authors. Journal compilation © 2009 Blackwell Publishing Ltd.

  16. Identification of Submergence-Responsive MicroRNAs and Their Targets Reveals Complex MiRNA-Mediated Regulatory Networks in Lotus (Nelumbo nucifera Gaertn)

    PubMed Central

    Jin, Qijiang; Xu, Yingchun; Mattson, Neil; Li, Xin; Wang, Bei; Zhang, Xiao; Jiang, Hongwei; Liu, Xiaojing; Wang, Yanjie; Yao, Dongrui

    2017-01-01

    MicroRNAs (miRNAs) are endogenous non-coding RNAs with important regulatory functions in plant development and stress responses. However, their population abundance in lotus (Nelumbo nucifera Gaertn) has so far been poorly described, particularly in response to stresses. In this work, submergence-related miRNAs and their target genes were systematically identified, compared, and validated at the transcriptome-wide level using high-throughput sequencing data of small RNA, Mrna, and the degradome. A total of 128 known and 20 novel miRNAs were differentially expressed upon submergence. We identified 629 target transcripts for these submergence-responsive miRNAs. Based on the miRNA expression profiles and GO and KEGG annotation of miRNA target genes, we suggest possible molecular responses and physiological changes of lotus in response to submergence. Several metabolic, physiological and morphological adaptations-related miRNAs, i.e., NNU_far-miR159, NNU_gma-miR393h, and NNU_aly-miR319c-3p, were found to play important regulatory roles in lotus response to submergence. This work will contribute to a better understanding of miRNA-regulated adaption responses of lotus to submergence stress. PMID:28149304

  17. Transcriptomic analysis of submergence-tolerant and sensitive Brachypodium distachyon ecotypes reveals oxidative stress as a major tolerance factor

    PubMed Central

    Rivera-Contreras, Irma Karla; Zamora-Hernández, Teresa; Huerta-Heredia, Ariana Arlene; Capataz-Tafur, Jacqueline; Barrera-Figueroa, Blanca Estela; Juntawong, Piyada; Peña-Castro, Julián Mario

    2016-01-01

    When excessive amounts of water accumulate around roots and aerial parts of plants, submergence stress occurs. To find the integrated mechanisms of tolerance, we used ecotypes of the monocot model plant Brachypodium distachyon to screen for genetic material with contrasting submergence tolerance. For this purpose, we used a set of previously studied drought sensitive/tolerant ecotypes and the knowledge that drought tolerance is positively associated with submergence stress. We decided to contrast aerial tissue transcriptomes of the ecotype Bd21 14-day-old plants as sensitive and ecotype Bd2-3 as tolerant after 2 days of stress under a long-day photoperiod. Gene ontology and the grouping of transcripts indicated that tolerant Bd2-3 differentially down-regulated NITRATE REDUCTASE and ALTERNATIVE OXIDASE under stress and constitutively up-regulated HAEMOGLOBIN, when compared with the sensitive ecotype, Bd21. These results suggested the removal of nitric oxide, a gaseous phytohormone and concomitant reactive oxygen species as a relevant tolerance determinant. Other mechanisms more active in tolerant Bd2-3 were the pathogen response, glyoxylate and tricarboxylic acid cycle integration, and acetate metabolism. This data set could be employed to design further studies on the basic science of plant tolerance to submergence stress and its biotechnological application in the development of submergence-tolerant crops. PMID:27282694

  18. Cyanobacterial construction of hot spring siliceous stromatolites in Yellowstone National Park.

    PubMed

    Pepe-Ranney, Charles; Berelson, William M; Corsetti, Frank A; Treants, Merika; Spear, John R

    2012-05-01

    Living stromatolites growing in a hot spring in Yellowstone National Park are composed of silica-encrusted cyanobacterial mats. Two cyanobacterial mat types grow on the stromatolite surfaces and are preserved as two distinct lithofacies. One mat is present when the stromatolites are submerged or at the water-atmosphere interface and the other when stromatolites protrude from the hot spring. The lithofacies created by the encrustation of submerged mats constitutes the bulk of the stromatolites, is comprised of silica-encrusted filaments, and is distinctly laminated. To better understand the cyanobacterial membership and community structure differences between the mats, we collected mat samples from each type. Molecular methods revealed that submerged mat cyanobacteria were predominantly one novel phylotype while the exposed mats were predominantly heterocystous phylotypes (Chlorogloeopsis HTF and Fischerella). The cyanobacterium dominating the submerged mat type does not belong in any of the subphylum groups of cyanobacteria recognized by the Ribosomal Database Project and has also been found in association with travertine stromatolites in a Southwest Japan hot spring. Cyanobacterial membership profiles indicate that the heterocystous phylotypes are 'rare biosphere' members of the submerged mats. The heterocystous phylotypes likely emerge when the water level of the hot spring drops. Environmental pressures tied to water level such as sulfide exposure and possibly oxygen tension may inhibit the heterocystous types in submerged mats. These living stromatolites are finely laminated and therefore, in texture, may better represent similarly laminated ancient forms compared with more coarsely laminated living marine examples. © 2012 Society for Applied Microbiology and Blackwell Publishing Ltd.

  19. Impact of plunging breaking waves on a partially submerged cube

    NASA Astrophysics Data System (ADS)

    Wang, A.; Ikeda, C.; Duncan, J. H.

    2013-11-01

    The impact of a deep-water plunging breaking wave on a partially submerged cube is studied experimentally in a tank that is 14.8 m long and 1.2 m wide with a water depth of 0.91 m. The breakers are created from dispersively focused wave packets generated by a programmable wave maker. The water surface profile in the vertical center plane of the cube is measured using a cinematic laser-induced fluorescence technique with movie frame rates ranging from 300 to 4,500 Hz. The pressure distribution on the front face of the cube is measured with 24 fast-response sensors simultaneously with the wave profile measurements. The cube is positioned vertically at three heights relative to the mean water level and horizontally at a distance from the wave maker where a strong vertical water jet is formed. The portion of the water surface between the contact point on the front face of the cube and the wave crest is fitted with a circular arc and the radius and vertical position of the fitted circle is tracked during the impact. The vertical acceleration of the contact point reaches more than 50 times the acceleration of gravity and the pressure distribution just below the free surface shows a localized high-pressure region with a very high vertical pressure gradient. This work is supported by the Office of Naval Research under grant N000141110095.

  20. Visualisation by high resolution synchrotron X-ray phase contrast micro-tomography of gas films on submerged superhydrophobic leaves.

    PubMed

    Lauridsen, Torsten; Glavina, Kyriaki; Colmer, Timothy David; Winkel, Anders; Irvine, Sarah; Lefmann, Kim; Feidenhans'l, Robert; Pedersen, Ole

    2014-10-01

    Floods can completely submerge terrestrial plants but some wetland species can sustain O2 and CO2 exchange with the environment via gas films forming on superhydrophobic leaf surfaces. We used high resolution synchrotron X-ray phase contrast micro-tomography in a novel approach to visualise gas films on submerged leaves of common cordgrass (Spartina anglica). 3D tomograms enabled a hitherto unmatched level of detail regarding the micro-topography of leaf gas films. Gas films formed only on the superhydrophobic adaxial leaf side (water droplet contact angle, Φ=162°) but not on the abaxial side (Φ=135°). The adaxial side of the leaves of common cordgrass is plicate with a longitudinal system of parallel grooves and ridges and the vast majority of the gas film volume was found in large ∼180μm deep elongated triangular volumes in the grooves and these volumes were connected to each neighbouring groove via a fine network of gas tubules (∼1.7μm diameter) across the ridges. In addition to the gas film retained on the leaf exterior, the X-ray phase contrast micro-tomography also successfully distinguished gas spaces internally in the leaf tissues, and the tissue porosity (gas volume per unit tissue volume) ranged from 6.3% to 20.3% in tip and base leaf segments, respectively. We conclude that X-ray phase contrast micro-tomography is a powerful tool to obtain quantitative data of exterior gas features on biological samples because of the significant difference in electron density between air, biological tissues and water. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Beach impacts of shore-parallel breakwaters backing offshore submerged ridges, Western Mediterranean Coast of Egypt.

    PubMed

    Iskander, Moheb M; Frihy, Omran E; El Ansary, Ahmed E; El Mooty, Mohamed M Abd; Nagy, Hossam M

    2007-12-01

    Seven breakwaters were constructed behind offshore submerged ridges to create a safe area for swimming and recreational activities west of Alexandria on the Mediterranean coast of Egypt. Morphodynamic evaluation was based on the modified Perlin and Dean numerical model (ImSedTran-2D) combined with successive shoreline and beach profile surveys conducted periodically between April 2001 and May 2005. Results reveal insignificant morphologic changes behind the detached breakwaters with slight coastline changes at the down and up-drift beaches of the examined breakwaters (+/-10 m). These changes are associated with salient accretion (20-7 0m) in the low-energy leeside of such structures. Concurrent with this sand accretion is the accumulation of a large amount of benthic algae (Sargassum) in the coastal water of the shadow area of these structures, which in turn have adverse effects on swimmers. Practical measures proposed in this study have successfully helped in mitigating such accumulation of algae in the recreation leeside of the breakwaters. The accumulation of Sargassum, together with the virtual insignificant changes in the up-drift and down-drifts of these structures, is a direct response to both coastal processes and the submerged carbonate ridges. Coastal processes encompass reversal of the directions of long-shore sand transport versus shoreline orientation, the small littoral drift rate and sand deficiency of the littoral zone. The beach response to the breakwaters together with the submerged ridges has also been confirmed by applying the ImSedTran-2D model. Results indicate that submerged ridges play a principal role in the evolution of beach morphology along the west coast of Alexandria. Although the study area is exposed to more than 70% wave exposures, the morphodynamic behavior of the beaches indicates that the submerged ridges act in a similar way as an additional natural barrier together with the artificial detached structures.

  2. 1. Deep Creek Road, picnic pavilion Great Smoky Mountains ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Deep Creek Road, picnic pavilion - Great Smoky Mountains National Park Roads & Bridges, Deep Creek Road, Between Park Boundary near Bryson City & Deep Creek Campground, Gatlinburg, Sevier County, TN

  3. Volcanism and Tectonics of the Central Deep Basin, Sea of Japan

    NASA Astrophysics Data System (ADS)

    Lelikov, E. P.; Emelyanova, T. A.; Pugachev, A. A.

    2018-01-01

    The paper presents the results of a study on the geomorphic structure, tectonic setting, and volcanism of the volcanoes and volcanic ridges in the deep Central Basin of the Sea of Japan. The ridges rise 500-600 m above the acoustic basement of the basin. These ridges were formed on fragments of thinned continental crust along deep faults submeridionally crossing the Central Basin and the adjacent continental part of the Primorye. The morphostructures of the basin began to submerge below sea level in the Middle Miocene and reached their contemporary positions in the Pliocene. Volcanism in the Central Basin occurred mostly in the Middle Miocene-Pliocene and formed marginal-sea basaltoids with OIB (ocean island basalt) geochemical signatures indicating the lower-mantle plume origin of these rocks. The OIB signatures of basaltoids tend to be expressed better in the eastern part of the Central Basin, where juvenile oceanic crust has developed. The genesis of this crust is probably related to rising and melting of the Pacific superplume apophyse.

  4. Macrofouling of deep-sea instrumentation after three years at 3690 m depth in the Charlie Gibbs fracture zone, mid-Atlantic ridge, with emphasis on hydroids (Cnidaria: Hydrozoa)

    NASA Astrophysics Data System (ADS)

    Blanco, R.; Shields, M. A.; Jamieson, A. J.

    2013-12-01

    Macrofouling is a common problem when deploying underwater instrumentation for long periods of time. It is a problem which can effect scientific experiments and monitoring missions though the creation of artificial reefs (thus increasing local biological activity) and reduce the quality of scientific data. Macrofouling is an issue typically considered to be restricted to the photic zones and is absent or negligible in the deep sea. To the contrary, the recovery of an accidentally lost deep-sea lander after 3 years submergence at 3960 m on the Mid-Atlantic Ridge (North Atlantic) revealed dense colonisation of macrofouling organisms. These organisms were found attached to all surfaces of the lander regardless of orientation and materials. The occurrence of such deep-sea macrofouling should be carefully investigated given the recent developments in long-term deep-sea observatory networks.

  5. Critical analysis of submerged membrane sequencing batch reactor operating conditions.

    PubMed

    McAdam, Ewan; Judd, Simon J; Gildemeister, René; Drews, Anja; Kraume, Matthias

    2005-10-01

    To evaluate the Submerged Membrane Sequencing Batch Reactor process, several short-term studies were conducted to define critical flux, membrane aeration and intermittent filtration operation. Critical flux trials indicated that as mixed liquor suspended solids increased in concentration so would the propensity for membrane fouling. Consequently in order to characterise the impact of biomass concentration increase (that develops during permeate withdrawal) upon submerged microfiltration operation, two longer term studies were conducted, one with a falling hydraulic head and another with a continuous hydraulic head (as in membrane bio-reactors). Trans membrane pressure data was used to predict the maximum possible operating periods at 10 and 62 days for the falling hydraulic head and continuous hydraulic head respectively. Further analysis revealed that falling hydraulic head operation would require 21% more aeration to maintain a consistent crossflow velocity than continuous operation and would rely on pumping for full permeate withdrawal 80% earlier. This study concluded that further optimisation would be required to make this technology technically and economically viable.

  6. Investigation of scour adjacent to submerged geotextiles used for shore protection

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gorton, Alicia M.; Herrington, Thomas O.; Smith, Ernest R.

    This study presents the results of an experimental investigation of morphology change in the vicinity of submerged geotextiles placed within the surf zone. The study was motivated by the emerging use of submerged geotextile tubes for shore protection, shoreline stabilization, and surf amenity enhancement and the need to understand the mechanisms responsible for scour in the vicinity of these structures to preserve their structural integrity and reduce their structural failure. A movable bed physical model experiment was conducted at the U.S. Army Engineer Research and Development Center’s Large-scale Sediment Transport Facility (LSTF) to develop empirical formulations to predict the meanmore » scour depth adjacent to geotextiles under oblique wave-breaking conditions as a function of the maximum Keulegan-Carpenter, Shields, and Reynolds numbers. The observed scour in the vicinity of the geotextiles was also compared to a previous study of scour in the vicinity of submerged cylinders. Formulations developed by Cataño-Lopera and García (2006) relating the Keulegan-Carpenter, Shields, and Reynolds numbers to the scour depth were used to predict the scour observed during the LSTF experiment. Results show that the formulations of Cataño-Lopera and García (2006) over-predict the observed scour when calculated using the maximum Keulegan-Carpenter, Shields, and Reynolds numbers. New, modified expressions of Cataño-Lopera and García (2006) were developed for use in oblique random wave fields.« less

  7. Mathematical investigation of tsunami-like long waves interaction with submerge dike of different thickness

    NASA Astrophysics Data System (ADS)

    Zhiltsov, Konstantin; Kostyushin, Kirill; Kagenov, Anuar; Tyryshkin, Ilya

    2017-11-01

    This paper presents a mathematical investigation of the interaction of a long tsunami-type wave with a submerge dike. The calculations were performed by using the freeware package OpenFOAM. Unsteady two-dimensional Navier-Stokes equations were used for mathematical modeling of incompressible two-phase medium. The Volume of Fluid (VOF) method is used to capture the free surface of a liquid. The effects caused by long wave of defined amplitude motion through a submerged dike of varying thickness were discussed in detail. Numerical results show that after wave passing through the barrier, multiple vortex structures were formed behind. Intensity of vortex depended on the size of the barrier. The effectiveness of the submerge barrier was estimated by evaluating the wave reflection and transmission coefficients using the energy integral method. Then, the curves of the dependences of the reflection and transmission coefficients were obtained for the interaction of waves with the dike. Finally, it was confirmed that the energy of the wave could be reduced by more than 50% when it passed through the barrier.

  8. 2. Deep Creek Road, old bridge at campground entrance. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Deep Creek Road, old bridge at campground entrance. - Great Smoky Mountains National Park Roads & Bridges, Deep Creek Road, Between Park Boundary near Bryson City & Deep Creek Campground, Gatlinburg, Sevier County, TN

  9. Formin homology 1 (OsFH1) regulates submergence-dependent root hair development in rice plants.

    PubMed

    Huang, Jin; Liu, Jingmiao; Han, Chang-Deok

    2013-08-01

    By using a forward genetic approach, a formin homology 1 gene (OsFH1) was identified as a critical regulator of rice root hair development. The phenotypic effect of OsFH1 on root hair development was verified by using three independent mutants, one point mutation and two T-DNA insertions. The study showed that OsFH1 is required for the elongation of root-hairs. However, Osfh1 exhibited growth defect of root hairs only when roots were grown submerged in solution. To understand how OsFH1 impinges on plant responses to root submergence, the growth responses of Osfh1 root hairs to anoxia, carbohydrate supplementation and exogenous hormones (auxin and ethylene) and nutrients (Fe and Pi) were examined. However, none of these treatments rescued the growth defects of Osfhl1 root hairs. This study demonstrates that OsFH1 could be involved in preventing submergence-induced inhibition of root hair growth.

  10. Suitability of seagrasses and submerged aquatic vegetation as indicators of eutrophication

    EPA Science Inventory

    Rooted submerged aquatic vegetation (SAV) encompasses a large diversity of species that range from obligate halophytes such as, seagrasses, to euryhaline species and freshwater obligates. All seagrass and SAV provide key biological functions within the enclosed bays, estuaries, a...

  11. Morphological divergence between three Arctic charr morphs - the significance of the deep-water environment.

    PubMed

    Skoglund, Sigrid; Siwertsson, Anna; Amundsen, Per-Arne; Knudsen, Rune

    2015-08-01

    Morphological divergence was evident among three sympatric morphs of Arctic charr (Salvelinus alpinus (L.)) that are ecologically diverged along the shallow-, deep-water resource axis in a subarctic postglacial lake (Norway). The two deep-water (profundal) spawning morphs, a benthivore (PB-morph) and a piscivore (PP-morph), have evolved under identical abiotic conditions with constant low light and temperature levels in their deep-water habitat, and were morphologically most similar. However, they differed in important head traits (e.g., eye and mouth size) related to their different diet specializations. The small-sized PB-morph had a paedomorphic appearance with a blunt head shape, large eyes, and a deep body shape adapted to their profundal lifestyle feeding on submerged benthos from soft, deep-water sediments. The PP-morph had a robust head, large mouth with numerous teeth, and an elongated body shape strongly related to their piscivorous behavior. The littoral spawning omnivore morph (LO-morph) predominantly utilizes the shallow benthic-pelagic habitat and food resources. Compared to the deep-water morphs, the LO-morph had smaller head relative to body size. The LO-morph exhibited traits typical for both shallow-water benthic feeding (e.g., large body depths and small eyes) and planktivorous feeding in the pelagic habitat (e.g., streamlined body shape and small mouth). The development of morphological differences within the same deep-water habitat for the PB- and PP-morphs highlights the potential of biotic factors and ecological interactions to promote further divergence in the evolution of polymorphism in a tentative incipient speciation process. The diversity of deep-water charr in this study represents a novelty in the Arctic charr polymorphism as a truly deep-water piscivore morph has to our knowledge not been described elsewhere.

  12. High-speed imaging of submerged jet: visualization analysis using proper orthogonality decomposition

    NASA Astrophysics Data System (ADS)

    Liu, Yingzheng; He, Chuangxin

    2016-11-01

    In the present study, the submerged jet at low Reynolds numbers was visualized using laser induced fluoresce and high-speed imaging in a water tank. Well-controlled calibration was made to determine linear dependency region of the fluoresce intensity on its concentration. Subsequently, the jet fluid issuing from a circular pipe was visualized using a high-speed camera. The animation sequence of the visualized jet flow field was supplied for the snapshot proper orthogonality decomposition (POD) analysis. Spatio-temporally varying structures superimposed in the unsteady fluid flow were identified, e.g., the axisymmetric mode and the helical mode, which were reflected from the dominant POD modes. The coefficients of the POD modes give strong indication of temporal and spectral features of the corresponding unsteady events. The reconstruction using the time-mean visualization and the selected POD modes was conducted to reveal the convective motion of the buried vortical structures. National Natural Science Foundation of China.

  13. Development and validation of phytotoxicity tests with emergent and submerged aquatic plants

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hughes, J.S.; Powell, R.L.; Nelson, M.K.

    1995-12-31

    Toxicity testing procedures have recently been developed for assessment of contaminant effects on emergent and submerged aquatic macrophytes commonly found in freshwater wetlands. These tests have potential application in risk assessments for contaminated wetlands as well as for new chemical substances. The objective of this study was to evaluate and modify, if necessary, these methods and to validate them, using two benchmark chemicals, in a contract laboratory setting. Oryza sativa (domestic rice) was used as a surrogate emergent vascular plant, while Ceratophylium demersum (coontail) and Myriophyllum heterophyllum (variable-leaf milfoil) were the representative submerged vascular plants. Subsequent to evaluating culturing techniquesmore » and testing conditions, toxicity tests were conducted using boron and metribuzin. The test procedure for the emergent plants involves a two-week pro-exposure period followed by a two-week aqueous exposure. Five types of sediment, including both natural and artificial sediments, were evaluated for use with rice. Fresh weight and chlorophyll a content were the selected test endpoints. The submerged plants were exposed for two weeks, and the response variables evaluated included length, weight (fresh and dry), and root number. The sensitivity of these tests were comparable to the results obtained for the same two chemicals using the green alga, Selenastrum capricornutum, and the duckweed, Lemna gibba, with the exception that rice was less sensitive to metribuzin than the other species.« less

  14. Biogeochemical impacts of submerging forests through large dams in the Rio Negro, Uruguay

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Campo, J.; Sancholuz, K.

    1998-09-01

    The Bonete, Baygorria and Palmar dams of the Rio Negro successively submerged complex floodplain forests. The forest area submerged was greater than 280 km{sup 2} and resulted in large inputs of carbon, nitrogen and phosphorus to the reservoirs. After 46 years wood released 40, 34 and 71% of their original contents of carbon, nitrogen and phosphorus, respectively. During the same period the total amount of nutrients released by wood in comparison to leaves and litter is slightly less for nitrogen, almost double for phosphorus and more than three times for carbon. These results suggest that wood decomposition in water maymore » have a role in the trophic state of reservoirs.« less

  15. Deep mantle roots and continental hypsometry: implications for whole-Earth elemental cycling, long-term climate, and the Cambrian explosion

    NASA Astrophysics Data System (ADS)

    Lee, C. T.

    2016-12-01

    Most of Earth's continents today are above sea level, but the presence of thick packages of ancient sediments on top of the stable cores of continents indicates that continents must have been submerged at least once in their past. Elevations of continents are controlled by the interplay between crustal thickness, mantle root thickness and the temperature of the ambient convecting mantle. The history of a continent begins with mountain building through magmatic or tectonic crustal thickening, during which exhumation of deep-seated igneous and metamorphic rocks are highest. Mountain building is followed by a long interval of subsidence as a result of continued, but decreasing erosion and thermal relaxation, the latter in the form of a growing thermal boundary layer. Subsidence is manifest first as a boring interval in which no sedimentary record is preserved, followed by continent-scale submergence wherein sediments are deposited directly on deep-seated igneous/metamorphic basement, generating a major disconformity. The terminal resting elevation of a mature continent, however, is defined by the temperature of the ambient convecting mantle: below sea level when the mantle is hot and above sea level when the mantle is cold. Using thermobarometric constraints on secular cooling of Earth's mantle, our results suggest that Earth, for most of its history, must have been a water world, with regions of land confined to narrow orogenic belts and oceans characterized by deep basins and shallow continental seas, the latter serving as repositories of sediments and key redox-sensitive biological nutrients, such as phosphorous. Cooling of the Earth led to the gradual and irreversible rise of the continents, culminating in rapid emergence, through fits and starts and possible instabilities in climate, between 500-1000 Ma. Such emergence fundamentally altered marine biogeochemical cycling, continental weathering and the global hydrologic cycle, defining the backdrop for the

  16. Method for cracking hydrocarbon compositions using a submerged reactive plasma system

    DOEpatents

    Kong, Peter C.

    1997-01-01

    A method for cracking a liquid hydrocarbon composition (e.g. crude oil) to produce a cracked hydrocarbon product. A liquid hydrocarbon composition is initially provided. An electrical arc is generated directly within the hydrocarbon composition so that the arc is entirely submerged in the composition. Arc generation is preferably accomplished using a primary and secondary electrode each having a first end submerged in the composition. The first ends of the electrodes are separated from each other to form a gap therebetween. An electrical potential is then applied to the electrodes to generate the arc within the gap. A reactive gas is thereafter delivered to the arc which forms a bubble around the arc. Gas delivery may be accomplished by providing a passageway through each electrode and delivering the gas through the passageways. The arc and gas cooperate to produce a plasma which efficiently cracks the hydrocarbon composition.

  17. Control of the mixing time in vessels agitated by submerged recirculating jets.

    PubMed

    Kennedy, Stephen; Bhattacharjee, Pradipto K; Bhattacharya, Sati N; Eshtiaghi, Nicky; Parthasarathy, Rajarathinam

    2018-01-01

    Submerged recirculating jet mixing systems are an efficient and economical method of agitating large tanks with a high hydraulic residence time. Much work has been carried out in developing design correlations to aid the predictions of the mixing time in such systems, with the first such correlation being developed nearly 70 years ago. In most of these correlations, the mixing time depends directly on the volume of the vessel and inversely on the injection velocity of the submerged jet. This work demonstrates, for the first time, that the distance between the injection and suction nozzles also significantly affects the mixing time and can be used to control this time scale. The study introduces a non-dimensional quantity that can be used as an adjustable parameter in systems where such control is desired.

  18. Control of the mixing time in vessels agitated by submerged recirculating jets

    PubMed Central

    Bhattacharjee, Pradipto K.; Bhattacharya, Sati N.; Eshtiaghi, Nicky; Parthasarathy, Rajarathinam

    2018-01-01

    Submerged recirculating jet mixing systems are an efficient and economical method of agitating large tanks with a high hydraulic residence time. Much work has been carried out in developing design correlations to aid the predictions of the mixing time in such systems, with the first such correlation being developed nearly 70 years ago. In most of these correlations, the mixing time depends directly on the volume of the vessel and inversely on the injection velocity of the submerged jet. This work demonstrates, for the first time, that the distance between the injection and suction nozzles also significantly affects the mixing time and can be used to control this time scale. The study introduces a non-dimensional quantity that can be used as an adjustable parameter in systems where such control is desired. PMID:29410817

  19. Teleseismic studies indicate existence of deep magma chamber below Yellowstone National Park

    USGS Publications Warehouse

    Iyer, H.M.

    1974-01-01

    The secrets of Yellowstone National Park's spectacular geysers and other hot water and steam phenomena are being explored by the U.S Geological Survey with the aid of distant earthquakes (teleseisms). For some time geologists have known that the remarkable array of steam and hot water displays, for which the park is internationally famous, is associated with intense volcanic activity that occurred in the reigon during the last 2 million years. The most recent volcanic eruption took place about 600,000 years ago creating a large caldera, or crater, 75 kilometers long and 50 kilometers wide. This caldera occupies most of the central part of the present-day park. geologists knew from studies of the surface geology that the volcanic activity which creates the present caldera was caused the present caldera was caused by a large body of magma, a mixture composed of molten rock, hot liquids, and gases, that had forced its way from the deep interior of the Earth into the upper mantle and crust below the Yellowstone area. The dimensions and depth below the surface of this magma body were largely unknown, however, because there was no way to "see" deep below the surface. A tool was needed that would enable earth scientists to look into the curst and upper mantle of the Earth. Such a tool became availabe with the installation by the Geological Survey of a network of seismograph stations in the park. 

  20. 46 CFR 42.07-10 - Submergence of load line marks.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... VOYAGES BY SEA Control, Enforcement, and Rights of Appeal § 42.07-10 Submergence of load line marks. (a... by sea, or on the Great Lakes, or during the voyage, or on arrival, the applicable load lines marked... when navigating the Great Lakes. (d) When a vessel departs from a port situated on a river or inland...

  1. 46 CFR 42.07-10 - Submergence of load line marks.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... VOYAGES BY SEA Control, Enforcement, and Rights of Appeal § 42.07-10 Submergence of load line marks. (a... by sea, or on the Great Lakes, or during the voyage, or on arrival, the applicable load lines marked... when navigating the Great Lakes. (d) When a vessel departs from a port situated on a river or inland...

  2. 46 CFR 42.07-10 - Submergence of load line marks.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... VOYAGES BY SEA Control, Enforcement, and Rights of Appeal § 42.07-10 Submergence of load line marks. (a... by sea, or on the Great Lakes, or during the voyage, or on arrival, the applicable load lines marked... when navigating the Great Lakes. (d) When a vessel departs from a port situated on a river or inland...

  3. 46 CFR 42.07-10 - Submergence of load line marks.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... VOYAGES BY SEA Control, Enforcement, and Rights of Appeal § 42.07-10 Submergence of load line marks. (a... by sea, or on the Great Lakes, or during the voyage, or on arrival, the applicable load lines marked... when navigating the Great Lakes. (d) When a vessel departs from a port situated on a river or inland...

  4. 46 CFR 42.07-10 - Submergence of load line marks.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... VOYAGES BY SEA Control, Enforcement, and Rights of Appeal § 42.07-10 Submergence of load line marks. (a... by sea, or on the Great Lakes, or during the voyage, or on arrival, the applicable load lines marked... when navigating the Great Lakes. (d) When a vessel departs from a port situated on a river or inland...

  5. Method for cracking hydrocarbon compositions using a submerged reactive plasma system

    DOEpatents

    Kong, P.C.

    1997-05-06

    A method is described for cracking a liquid hydrocarbon composition (e.g. crude oil) to produce a cracked hydrocarbon product. A liquid hydrocarbon composition is initially provided. An electrical arc is generated directly within the hydrocarbon composition so that the arc is entirely submerged in the composition. Arc generation is preferably accomplished using a primary and secondary electrode each having a first end submerged in the composition. The first ends of the electrodes are separated from each other to form a gap there between. An electrical potential is then applied to the electrodes to generate the arc within the gap. A reactive gas is thereafter delivered to the arc which forms a bubble around the arc. Gas delivery may be accomplished by providing a passageway through each electrode and delivering the gas through the passageways. The arc and gas cooperate to produce a plasma which efficiently cracks the hydrocarbon composition. 6 figs.

  6. Submerged arc welding of heavy plate

    NASA Technical Reports Server (NTRS)

    Wilson, R. A.

    1972-01-01

    The submerged arc process is particularly suitable for heavy plate welding because of its ability to combine very high deposit rates along with excellent quality. It does these things without the smoke and spatter often accompanying other processes. It is available today in several forms that are pointed to the fabricators of heavy sections with long, short or round about welds. Tandem arc full automatic equipment is particularly suitable for those long heavy welds where speed and deposit rate are of the first order. An attachment called long stick-out which makes use of the IR drop on long electrode extensions can be included on this equipment to increase deposition rates 50% or more.

  7. Submerged jet mixing in nuclear waste tanks: a correlation for jet velocity

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Daas, M.; Srivastava, R.; Roelant, D.

    2007-07-01

    Experimental studies were carried out in jet-stirred slurry tanks to correlate the influence of nozzle diameter, initial jet flow velocity, submerged depth of jet, tank diameter and slurry properties on the jet axial velocity. The tanks used in the experimental work had diameters of 0.3 m (1-ft) and 2.13 m (7-ft). The fluids emerged from nozzles of 0.003 m and 0.01 m in diameter, 1/8-inch and 3/8-inch respectively. The examined slurries were non-Newtonian and contained 5 weight percent total insoluble solids. The axial velocities along the centerline of a submerged jet stream were measured at different jet flow rates andmore » at various distances from the nozzle orifice (16 to 200 nozzle diameters) utilizing electromagnetic velocity meter. A new simplified correlation was developed to describe the jet axial velocity in submerged jet stirred tanks utilizing more than 350 data points. The Buckingham Pi theorem and non-linear regression method of multivariate approximation, in conjunction with the Gauss-Jordan elimination method, were used to develop the new correlation. The new correlation agreed well with the experimental data obtained from the current study. Good agreement was also possible with literature data except at large distances from the nozzle as the model slightly overestimated the jet axial velocity. The proposed correlation incorporates the contributions of system geometry, fluid properties, and external forces. Furthermore, it provides reasonable estimates of jet axial velocity. (authors)« less

  8. 46 CFR 28.515 - Submergence test as an alternative to stability calculations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... float in calm water after being submerged for 18 hours so that— (1) The vessel has an equilibrium heel... in paragraph (c) of this section, except that the equilibrium heel angle must not exceed 30° and the...

  9. Predicting submerged aquatic vegetation cover and occurrence in a Lake Superior estuary

    EPA Science Inventory

    Submerged aquatic vegetation (SAV) provides the biophysical basis for multiple ecosystem services in Great Lakes estuaries. Understanding sources of variation in SAV is necessary for sustainable management of SAV habitat. From data collected in 2011 using hydroacoustic survey met...

  10. A submerged ceramic membrane reactor for the p-nitrophenol hydrogenation over nano-sized nickel catalysts.

    PubMed

    Chen, R Z; Sun, H L; Xing, W H; Jin, W Q; Xu, N P

    2009-02-01

    The catalytic hydrogenation of p-nitrophenol to p-aminophenol over nano-sized nickel catalysts was carried out in a submerged ceramic membrane reactor. It has been demonstrated that the submerged ceramic membrane reactor is more suitable for the p-nitrophenol hydrogenation over nano-sized nickel catalysts compared with the side-stream ceramic membrane reactor, and the membrane module configuration has a great influence on the reaction rate of p-nitrophenol hydrogenation and the membrane treating capacity. The deactivation of nano-sized nickel is mainly caused by the adsorption of impurity on the surface of nickel and the increase of oxidation degree of nickel.

  11. Submerged Medium Voltage Cable Systems at Nuclear Power Plants. A Review of Research Efforts Relevant to Aging Mechanisms and Condition Monitoring

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brown, Jason; Bernstein, Robert; White, II, Gregory Von

    academic and industrial literature was performed to identify : 1) findings regarding the degradation mechanisms of submerged cabling and 2) condition monitoring methods that may prove useful in predict ing the remaining lifetime of submerged medium voltage p ower cables . The re search was conducted by a multi - disciplinary team , and s ources includ ed official NRC reports, n ational l aboratory reports , IEEE standards, conference and journal proceedings , magazine articles , PhD dissertations , and discussions with experts . The purpose of this work was to establish the current state - of - the - art in material degradation modeling and cable condition monitoring techniques and to identify research gaps . Subsequently, future areas of focus are recommended to address these research gaps and thus strengthen the efficacy of the NRC's developing cable condition monitoring program . Results of this literature review and details of the test ing recommendations are presented in this report . FOREWORD To ensure the safe, re liable, and cost - effective long - term operation of nuclear power plants, many systems, structures, and components must be continuously evaluated. The Nuclear Regulatory Commission (NRC) has identified that cables in submerged environments are of concern, particularly as plants are seeking license renewal. To date, there is a lack of consensus on aging and degradation mechanisms even though the area of submerged cables has been extensively studied. Consequently, the ability to make lifetime predictions for submerged cable does not yet exist. The NRC has engaged Sandia National Laboratories (SNL) to lead a coordinated effort to help elucidate the aging and degradation of cables in submerged environments by collaborating with cable manufacturers, utilities, universities, and other government agencies. A team of SNL experts was assembled from the laboratories including electrical condition monitoring, mat erial science, polymer degradation, plasma physics

  12. Effects of surrounding land use on metal accumulation in environments and submerged plants in subtropical ponds.

    PubMed

    Liu, Hui; Bu, Hongmei; Liu, Guihua; Wang, Zhixiu; Liu, Wenzhi

    2015-12-01

    Ponds are widely used as stormwater treatment facilities to retain contaminants, including metals, and to improve water quality throughout the world. However, there is still a limited understanding of the effects of surrounding land use on metal accumulation in pond environments and organisms. To address this gap, we measured the concentrations of nine metals (i.e., Al, Ba, Ca, K, Li, Mg, Na, Se, and Sr) in water, sediments, and submerged plants collected from 37 ponds with different surrounding land uses in southwestern China and assessed the metal accumulation capacity of four dominant submerged plant species. Our results showed that Al, Ca, and K concentrations in the water were above drinking water standards. In the sediments, the average concentrations of Ca and Sr were higher than the corresponding soil background values. Ceratophyllum demersum L. could accumulate more K in aboveground biomass than Myriophyllum spicatum L. and Potamogeton maackianus A. Benn. The K concentration in submerged plants was positively influenced by the corresponding metal concentration in the water and negatively influenced by water temperature. Among the nine studied metals, only the water K concentration in ponds receiving agricultural runoff was significantly higher than that for ponds receiving urban and forested runoff. This result suggests that surrounding land use types have no significant effect on metal accumulation in sediments and submerged plants in the studied ponds. A large percentage of the metals in these ponds may be derived from natural sources such as the weathering of rocks.

  13. Scale resolving computation of submerged wall jets on flat wall with different roughness heights

    NASA Astrophysics Data System (ADS)

    Paik, Joongcheol; Bombardelli, Fabian

    2014-11-01

    Scale-adaptive simulation is used to investigate the response of velocity and turbulence in submerged wall jets to abrupt changes from smooth to rough beds. The submerged wall jets were experimentally investigated by Dey and Sarkar [JFM, 556, 337, 2006] at the Reynolds number of 17500 the Froude number of 4.09 and the submergence ratio of 1.12 on different rough beds that were generated by uniform sediments of different median diameters The SAS is carried out by means of a second-order-accurate finite volume method in space and time and the effect of bottom roughness is treated by the approach of Cebeci (2004). The evolution of free surface is captured by employing the two-phase volume of fluid (VOF) technique. The numerical results obtained by the SAS approach, incorporated with the VOF and the rough wall treatment, are in good agreement with the experimental measurements. The computed turbulent boundary layer grows more quickly and the depression of the free surface is more increased on the rough wall than those on smooth wall. The size of the fully developed zone shrinks and the decay rate of maximum streamwise velocity and Reynolds stress components are faster with increase in the wall roughness. Supported by NSF and NRF of Korea.

  14. [Assessment of Antitumor Effect of Submerged Culture of Ophiocordyceps sinensis and Cordyceps militaris].

    PubMed

    Avtonomova, A V; Krasnopolskaya, L M; Shuktueva, M I; Isakova, E B; Bukhman, V M

    2015-01-01

    Ophiocordyceps sinensis and Cordyceps militaris metabolites showed a high potential in the treatment of tumors as well as some other diseases. Antitumor properties of O. sinensis and C. militaris submerged mycelium were investigated. It was found that the O. sinensis dry biomass in a dose of 50 mg/kg administered once a day to the mice with subcutaneously inoculated P388 lympholeucosis lowered the tumor growth by 65% vs. 54% for the C. militaris dry biomass. The water extract of O. sinensis submerged culture however accelerated the growth of the P388 lympholeucosis tumor node in the mice almost two times, compared to the control. A greater caution in using this fungus as a source of biologically active substances is required since unwanted tumor-stimulating effects can arise.

  15. Remote sensing of submerged aquatic vegetation in the lower Chesapeake Bay. [(sea grasses)

    NASA Technical Reports Server (NTRS)

    Orth, R. J.; Gordon, H. R.

    1975-01-01

    An experimental water penetration film and black and white near infrared film were used to study the distribution of submerged aquatic vegetation in the lower Chesapeake Bay. Detailed description of the grass beds was obtained by flying at an altitude of 5,000 feet, at low tide when wind conditions were minimal. Results show that there was a 36% reduction in the amount of submerged aquatic vegetation in the lower Chesapeake Bay from 1971 to 1974, the greatest losses occurring in the York, Piankatank and Rappahannock rivers (tabulated data is given). Recovery of some grass beds occurs primarily through seedling recruitment and subsequent vegetative growth. Cownose rays are suspected as a main factor for the decimation of some of the grass beds. Maps and photographs of the areas studied are given.

  16. Submerged Humid Tropical Karst Landforms Observed By High-Resolution Multibeam Survey in Nagura Bay, Ishigaki Island, Southwestern Japan

    NASA Astrophysics Data System (ADS)

    Kan, H.; Urata, K.; Nagao, M.; Hori, N.; Fujita, K.; Yokoyama, Y.; Nakashima, Y.; Ohashi, T.; Goto, K.; Suzuki, A.

    2014-12-01

    Submerged tropical karst features were discovered in Nagura Bay on Ishigaki Island in the South Ryukyu Islands, Japan. This is the first description of submerged humid tropical karst using multibeam bathymetry. We conducted a broadband multibeam survey in the central area of Nagura Bay (1.85 × 2.7 km) and visualized the high-resolution bathymetric results with a grid size of 1 m over a depth range of 1.6-58.5 m. Various types of humid tropical karst landforms were found to coexist within the bay, including fluviokarst, doline karst, cockpit karst, polygonal karst, uvalas, and mega-dolines. We assume that Nagura Bay was a large karst basin in which older limestone remained submerged, thus preventing corrosion and the accumulation of reef sediments during periods of submersion, whereas the limestone outcropping on land was corroded during multiple interglacial and glacial periods. Based on our bathymetric result together with aerial photographs of the coastal area, we conclude that the submerged karst landscape has likely developed throughout the whole of Nagura Bay, covering an area of ~6 × 5 km. Accordingly, this area hosts the largest submerged karst in Japan. We also observed abundant coral communities during our SCUBA observations. The present marine conditions of Nagura Bay are characterized by low energy (calm sea) and low irradiance owing to the terrestrial influence. Such conditions have been emphasized by the presence of large undulating landforms, which cause decreases in wave intensity and irradiance with depth. These characteristics have acted to establish unique conditions compared to other coral reef areas in the Ryukyu Islands. It may play an important role in supporting the regional coral reef ecosystem.

  17. The deep ocean under climate change

    NASA Astrophysics Data System (ADS)

    Levin, Lisa A.; Le Bris, Nadine

    2015-11-01

    The deep ocean absorbs vast amounts of heat and carbon dioxide, providing a critical buffer to climate change but exposing vulnerable ecosystems to combined stresses of warming, ocean acidification, deoxygenation, and altered food inputs. Resulting changes may threaten biodiversity and compromise key ocean services that maintain a healthy planet and human livelihoods. There exist large gaps in understanding of the physical and ecological feedbacks that will occur. Explicit recognition of deep-ocean climate mitigation and inclusion in adaptation planning by the United Nations Framework Convention on Climate Change (UNFCCC) could help to expand deep-ocean research and observation and to protect the integrity and functions of deep-ocean ecosystems.

  18. Bistatic scattering from submerged unexploded ordnance lying on a sediment.

    PubMed

    Bucaro, J A; Simpson, H; Kraus, L; Dragonette, L R; Yoder, T; Houston, B H

    2009-11-01

    The broadband bistatic target strengths (TSs) of two submerged unexploded ordnance (UXO) targets have been measured in the NRL sediment pool facility. The targets-a 5 in. rocket and a 155 mm projectile-were among the targets whose monostatic TSs were measured and reported previously by the authors. Bistatic TS measurements were made for 0 degrees (target front) and 90 degrees (target side) incident source directions, and include both backscattered and forward scattered echo angles over a complete 360 degrees with the targets placed proud of the sediment surface. For the two source angles used, each target exhibits two strong highlights: a backscattered specular-like echo and a forward scattered response. The TS levels of the former are shown to agree reasonably well with predictions, based on scattering from rigid disks and cylinders, while the levels of the latter with predictions from radar cross section models, based on simple geometric optics appropriately modified. The bistatic TS levels observed for the proud case provide comparable or higher levels of broadband TS relative to free-field monostatic measurements. It is concluded that access to bistatic echo information in operations aimed at detecting submerged UXO targets could provide an important capability.

  19. Analysis of enzyme production by submerged culture of Aspergillus oryzae using whole barley.

    PubMed

    Masuda, Susumu; Kikuchi, Kaori; Matsumoto, Yuko; Sugimoto, Toshikazu; Shoji, Hiroshi; Tanabe, Masayuki

    2009-10-01

    We have reported on high enzyme production by submerged culture of Aspergillus kawachii using barley with the husk (whole barley). To elucidate the mechanism underlying this high enzyme production, we performed a detailed analysis. Aspergillus oryzae RIB40 was submerged-cultured using whole barley and milled whole barley. Enzyme production was analyzed in terms of changes in medium components and gene expression levels. When whole barley was used, high production of glucoamylase and alpha-amylase and high gene expression levels of these enzymes were observed. Low ammonium concentrations were maintained with nitrate ion uptake continuing into the late stage using whole barley. These findings suggest that the sustainability of nitrogen metabolism is related to high enzyme production, and that a mechanism other than that associated with the conventional amylase expression system is involved in this relationship.

  20. Shallow Water Habitat Mapping in Cape Cod National Seashore: A Post-Hurricane Sandy Study

    NASA Astrophysics Data System (ADS)

    Borrelli, M.; Smith, T.; Legare, B.; Mittermayr, A.

    2017-12-01

    Hurricane Sandy had a dramatic impact along coastal areas in proximity to landfall in late October 2012, and those impacts have been well-documented in terrestrial coastal settings. However, due to the lack of data on submerged marine habitats, similar subtidal impact studies have been limited. This study, one of four contemporaneous studies commissioned by the US National Park Service, developed maps of submerged shallow water marine habitats in and around Cape Cod National Seashore, Massachusetts. All four studies used similar methods of data collection, processing and analysis for the production of habitat maps. One of the motivations for the larger study conducted in the four coastal parks was to provide park managers with a baseline inventory of submerged marine habitats, against which to measure change after future storm events and other natural and anthropogenic phenomena. In this study data from a phase-measuring sidescan sonar, bottom grab samples, seismic reflection profiling, and sediment coring were all used to develop submerged marine habitat maps using the Coastal and Marine Ecological Classification Standard (CMECS). Vessel-based acoustic surveys (n = 76) were conducted in extreme shallow water across four embayments from 2014-2016. Sidescan sonar imagery covering 83.37 km2 was collected, and within that area, 49.53 km2 of co-located bathymetric data were collected with a mean depth of 4.00 m. Bottom grab samples (n = 476) to sample macroinvertebrates and sediments (along with other water column and habitat data) were collected, and these data were used along with the geophysical and coring data to develop final habitat maps using the CMECS framework.

  1. The deep ocean under climate change.

    PubMed

    Levin, Lisa A; Le Bris, Nadine

    2015-11-13

    The deep ocean absorbs vast amounts of heat and carbon dioxide, providing a critical buffer to climate change but exposing vulnerable ecosystems to combined stresses of warming, ocean acidification, deoxygenation, and altered food inputs. Resulting changes may threaten biodiversity and compromise key ocean services that maintain a healthy planet and human livelihoods. There exist large gaps in understanding of the physical and ecological feedbacks that will occur. Explicit recognition of deep-ocean climate mitigation and inclusion in adaptation planning by the United Nations Framework Convention on Climate Change (UNFCCC) could help to expand deep-ocean research and observation and to protect the integrity and functions of deep-ocean ecosystems. Copyright © 2015, American Association for the Advancement of Science.

  2. CFD Modeling of Swirl and Nonswirl Gas Injections into Liquid Baths Using Top Submerged Lances

    NASA Astrophysics Data System (ADS)

    Huda, Nazmul; Naser, J.; Brooks, G.; Reuter, M. A.; Matusewicz, R. W.

    2010-02-01

    Fluid flow phenomena in a cylindrical bath stirred by a top submerged lance (TSL) gas injection was investigated by using the computational fluid dynamic (CFD) modeling technique for an isothermal air-water system. The multiphase flow simulation, based on the Euler-Euler approach, elucidated the effect of swirl and nonswirl flow inside the bath. The effects of the lance submergence level and the air flow rate also were investigated. The simulation results for the velocity fields and the generation of turbulence in the bath were validated against existing experimental data from the previous water model experimental study by Morsi et al.[1] The model was extended to measure the degree of the splash generation for different liquid densities at certain heights above the free surface. The simulation results showed that the two-thirds lance submergence level provided better mixing and high liquid velocities for the generation of turbulence inside the water bath. However, it is also responsible for generating more splashes in the bath compared with the one-third lance submergence level. An approach generally used by heating, ventilation, and air conditioning (HVAC) system simulations was applied to predict the convective mixing phenomena. The simulation results for the air-water system showed that mean convective mixing for swirl flow is more than twice than that of nonswirl in close proximity to the lance. A semiempirical equation was proposed from the results of the present simulation to measure the vertical penetration distance of the air jet injected through the annulus of the lance in the cylindrical vessel of the model, which can be expressed as L_{va} = 0.275( {do - di } )Frm^{0.4745} . More work still needs to be done to predict the detail process kinetics in a real furnace by considering nonisothermal high-temperature systems with chemical reactions.

  3. MAPPING AND MONITORING OF SUBMERGED AQUATIC VEGETATION IN ESCAMBIA-PENSACOLA BAY SYSTEM, FLORIDA.

    EPA Science Inventory

    Recently, the distribution and changes in submerged aquatic vegetation (SAV) in the Escambia-Pensacola Bay System in northwestern Florida were monitored by two techniques. One technique used divers to measure changes in the deepwater margin of beds and provided horizontal growth...

  4. Monitoring the effects of floods on submerged macrophytes in a large river.

    PubMed

    Ibáñez, Carles; Caiola, Nuno; Rovira, Albert; Real, Montserrat

    2012-12-01

    The lower Ebro River (Catalonia, Spain) has recently undergone a regime shift from a phytoplankton to a macrophyte-dominated system. Macrophytes started to spread at the end of the 1990s and since 2002 artificial floods (flushing flows) of short duration (1-2 days) are released from the Riba-roja dam once or twice a year in order to reduce macrophyte density. The aim of this study was to analyse the spatiotemporal trends of the submerged macrophytes in two stretches of the lower Ebro River using high-resolution hydroacoustic methods, in order to elucidate the effects of artificial floods and natural floods on its distribution and abundance. Results showed that the mean cover in the two studied stretches (Móra and Ginestar) was not reduced after a flushing flow (from 36.59% to 55.85% in Móra, and from 21.18% to 21.05% in Ginestar), but it was greatly reduced after the natural flood (down to 9.79% in Móra and 2.04% in Ginestar); surprisingly the cover increased in Móra after the artificial flood. In order to increase the efficiency of floods in controlling macrophyte spreading, the magnitude and frequency of them should largely increase, as well as the suspended sediment load, approaching as much as possible to the original flood pattern before dam construction. Hydroacoustic methods combined with geostatistics and interpolation in GIS can accurately monitor spatiotemporal trends of submerged macrophytes in large rivers. This is the first article to apply this monitoring system to submerged macrophytes in rivers. Copyright © 2012 Elsevier B.V. All rights reserved.

  5. Statistical porcess control in Deep Space Network operation

    NASA Technical Reports Server (NTRS)

    Hodder, J. A.

    2002-01-01

    This report describes how the Deep Space Mission System (DSMS) Operations Program Office at the Jet Propulsion Laboratory's (EL) uses Statistical Process Control (SPC) to monitor performance and evaluate initiatives for improving processes on the National Aeronautics and Space Administration's (NASA) Deep Space Network (DSN).

  6. Crassulacean acid metabolism in submerged aquatic plants

    USGS Publications Warehouse

    Keeley, Jon E.; Sybesme, C.

    1984-01-01

    CO2-fixation in the dark is known to occur in various organs of many plants. However, only in species possessing crassulacean acid metabolism (CAM) does dark CO2-fixation contribute substantially to the carbon economy of the plant. Until very recently CAM was known only from terrestrial species, largely drought adapted succulents. The discovery of CAM in the submerged aquatic fern ally Isoetes howellii (Isoetaceae)(Keeley 1981) adds a new dimension to our understanding of crassulacean acid metabolism. In this paper I will summarize 1) the evidence of CAM in Isoetes howellii, 2) the data on the distribution of CAM in aquatic species, and 3) the work to date on the functional significance of CAM in aquatic species.

  7. Statistical optimization of lovastatin production by Omphalotus olearius (DC.) singer in submerged fermentation.

    PubMed

    Atlı, Burcu; Yamaç, Mustafa; Yıldız, Zeki; Isikhuemhen, Omoanghe S

    2016-01-01

    In this study, culture conditions were optimized to improve lovastatin production by Omphalotus olearius, isolate OBCC 2002, using statistical experimental designs. The Plackett-Burman design was used to select important variables affecting lovastatin production. Accordingly, glucose, peptone, and agitation speed were determined as the variables that have influence on lovastatin production. In a further experiment, these variables were optimized with a Box-Behnken design and applied in a submerged process; this resulted in 12.51 mg/L lovastatin production on a medium containing glucose (10 g/L), peptone (5 g/L), thiamine (1 mg/L), and NaCl (0.4 g/L) under static conditions. This level of lovastatin production is eight times higher than that produced under unoptimized media and growth conditions by Omphalotus olearius. To the best of our knowledge, this is the first attempt to optimize submerged fermentation process for lovastatin production by Omphalotus olearius.

  8. Coastal submergence at Ukishima-ga-hara adjacent to the Suruga Trough (eastern Nankai Trough), central Japan, inferred from diatoms and plant macrofossils

    NASA Astrophysics Data System (ADS)

    Sawai, Y.; Momohara, A.

    2017-12-01

    Five episodic submergence events during the past 3500 years were recognized at the Ukishima-ga-hara lowland, northern coast of Suruga Trough (eastern Nankai Trough). Coastal submergence in this region was originally reported by Osamu Fujiwara and his colleagues (e.g., Fujiwara et al., 2016) based mainly on changes in lithostratigraphy from a peaty layer that abruptly changed to a light-colored mud and results of microfossil analyses (pollen and diatoms from 57 and 13 samples, respectively). They attributed the submergence events to coseismic deformation associated with earthquakes in the Fujikawa-kako fault zone or Suruga Trough. Here I reevaluated the micropaleontology of this area using 200 samples from 15 cores to reconstruct the full history of coastal submergence during the last few thousand years. The submergence events were shown not by lithostratigraphy but clearly by changes in fossil diatom assemblages and plant macrofossils. For example, at about 2.3 m and 3.1 m below the ground surface, while aerophilic diatoms (such as Diadesmis contenta and Diploneis elliptica) dominate the underlying peaty layer, freshwater and brackish planktonic taxa (Aulacoseira and Thalassiosira) abound in the overlying layer. As many as five such changes in diatom assemblages were found in a 8-m core and radiocarbon ages constrain the age of the entire sequence to 3500 yr BP.

  9. Design and Analysis of Embedded I&C for a Fully Submerged Magnetically Suspended Impeller Pump

    DOE PAGES

    Melin, Alexander M.; Kisner, Roger A.

    2018-04-03

    Improving nuclear reactor power system designs and fuel-processing technologies for safer and more efficient operation requires the development of new component designs. In particular, many of the advanced reactor designs such as the molten salt reactors and high-temperature gas-cooled reactors have operating environments beyond the capability of most currently available commercial components. To address this gap, new cross-cutting technologies need to be developed that will enable design, fabrication, and reliable operation of new classes of reactor components. The Advanced Sensor Initiative of the Nuclear Energy Enabling Technologies initiative is investigating advanced sensor and control designs that are capable of operatingmore » in these extreme environments. Under this initiative, Oak Ridge National Laboratory (ORNL) has been developing embedded instrumentation and control (I&C) for extreme environments. To develop, test, and validate these new sensing and control techniques, ORNL is building a pump test bed that utilizes submerged magnetic bearings to levitate the shaft. The eventual goal is to apply these techniques to a high-temperature (700°C) canned rotor pump that utilizes active magnetic bearings to eliminate the need for mechanical bearings and seals. The technologies will benefit the Next Generation Power Plant, Advanced Reactor Concepts, and Small Modular Reactor programs. In this paper, we will detail the design and analysis of the embedded I&C test bed with submerged magnetic bearings, focusing on the interplay between the different major systems. Then we will analyze the forces on the shaft and their role in the magnetic bearing design. Next, we will develop the radial and thrust bearing geometries needed to meet the operational requirements of the test bed. In conclusion, we will present some initial system identification results to validate the theoretical models of the test bed dynamics.« less

  10. Design and Analysis of Embedded I&C for a Fully Submerged Magnetically Suspended Impeller Pump

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Melin, Alexander M.; Kisner, Roger A.

    Improving nuclear reactor power system designs and fuel-processing technologies for safer and more efficient operation requires the development of new component designs. In particular, many of the advanced reactor designs such as the molten salt reactors and high-temperature gas-cooled reactors have operating environments beyond the capability of most currently available commercial components. To address this gap, new cross-cutting technologies need to be developed that will enable design, fabrication, and reliable operation of new classes of reactor components. The Advanced Sensor Initiative of the Nuclear Energy Enabling Technologies initiative is investigating advanced sensor and control designs that are capable of operatingmore » in these extreme environments. Under this initiative, Oak Ridge National Laboratory (ORNL) has been developing embedded instrumentation and control (I&C) for extreme environments. To develop, test, and validate these new sensing and control techniques, ORNL is building a pump test bed that utilizes submerged magnetic bearings to levitate the shaft. The eventual goal is to apply these techniques to a high-temperature (700°C) canned rotor pump that utilizes active magnetic bearings to eliminate the need for mechanical bearings and seals. The technologies will benefit the Next Generation Power Plant, Advanced Reactor Concepts, and Small Modular Reactor programs. In this paper, we will detail the design and analysis of the embedded I&C test bed with submerged magnetic bearings, focusing on the interplay between the different major systems. Then we will analyze the forces on the shaft and their role in the magnetic bearing design. Next, we will develop the radial and thrust bearing geometries needed to meet the operational requirements of the test bed. In conclusion, we will present some initial system identification results to validate the theoretical models of the test bed dynamics.« less

  11. New constraints on the structure of Hess Deep from regional- and micro-bathymetry data acquired during RRS James Cook in Jan-Feb 2008 (JC021)

    NASA Astrophysics Data System (ADS)

    Shillington, D. J.; Ferrini, V. L.; MacLeod, C. J.; Teagle, D. A.; Gillis, K. M.; Cazenave, P. W.; Hurst, S. D.; Scientific Party, J.

    2008-12-01

    . Following the cruise, we reprocessed navigation and sonar data using software tools developed through National Deep Submergence Facility (USA) to 1) regenerate seafloor picks with more robust algorithm, 2) incorporate high-resolution navigation (which could not be included in shipboard processing) and 3) correct for attitude variations. The first survey covers a ~15 km2 area on the south-facing slope of the Intrarift Ridge immediately north of the Deep, where lower crustal gabbros have been sampled by Isis during JC021 and by dredging and other deep submergence vehicles during previous cruises. This area also contains the highest priority drill sites from IODP Proposal 551-Full. The second survey covers a ~5.5 km2 area on the Intrarift Ridge and its southern flank, including the location of ODP Site 894. Both grids show structures that strike both E-W and NE-SW, similar to what is observed at a larger scale in the regional bathymetry data. The first survey area also contains a series of sedimented benches, which might be suitable drilling targets. The second survey is characterized by steep scarps that predominantly strike NE-SW. These features were observed to correspond to sizable cliffs during seafloor operations with Isis.

  12. Cobalt Distribution and Speciation: Effect of Aging, Intermittent Submergence, In situ Rice Roots

    EPA Science Inventory

    The speciation and distribution of cobalt (Co) in soils is poorly understood. This study was conducted using X-ray absorption spectroscopy (XAS) techniques to examine the influence of soluble Co(II) aging, submergence-dried cycling, and the presence of in vivo rice roots on the...

  13. [Dynamics of genome changes in Rauwolfia serpentina callus tissue upon the switch to conditions of submerged cultivation].

    PubMed

    Spiridonova, E V; Adnof, D M; Andreev, I O; Kunakh, V A

    2008-01-01

    Genome of Rauwolfia serpentina callus cells was found to fail undergo the noticeable changes for several early passages upon the switch from surface to submerged cultivation in the liquid medium of special composition. After subsequent 4-6 passages in submerged culture RAPD spectra polymorphism was revealed which may reflect the changes in DNA sequence as well as in the structure of cell population that forms the strain. Introduction of the intermediary passage on the agar-solidified medium of more simple composition prior to transfer into liquid medium appeared not to affect essentially the level and the pattern of genome changes.

  14. Mission Accomplished: Deep Submergence Science Routinely Supported Using Multiple Vehicles Throughout the Hawaii Undersea Research Laboratory's 2005 South Pacific Expedition

    NASA Astrophysics Data System (ADS)

    Kerby, T.; Smith, J. R.; Shackelford, R.; Wiltshire, J. C.; Malahoff, A.

    2005-12-01

    The Hawaii Undersea Research Laboratory (HURL) recently completed an internationally partnered 5-month, 14,500 nautical mile multiple leg expedition to the South Pacific that included 21 study sites in the waters of American Samoa, New Zealand, Tonga, and the U.S. Line Islands to commemorate its 25th anniversary of supporting deep submergence science in the Pacific Ocean. During this voyage, HURL successfully operated its two human occupied vehicles ( Pisces IV and Pisces V) each capable of diving to 2000 m from their support ship, the R/V Ka'imikai-o-Kanaloa ( KoK). In addition, a remotely operated vehicle ( RCV-150) with a nearly 1000-m depth limit was utilized alternately with the Pisces HOV's. The size and organized placement of these vehicles on the compact but efficiently run KoK (70-m length, 2000-tons displacement, 14 crew) allowed for deployment of a CTD rosette system and recovery of instrument package moorings during the same cruise leg. The Pisces submersibles are 20-ft long, 13-ton, 3-person vehicles with 7-10 hours duration, up to 350-lb payload capacities, and three forward looking viewports. The small size of the Pisces' relative to much larger deeper diving HOV's increases their agility, thus allowing maneuvering into more difficult sampling site terrain. The smaller package also facilitates rapid launch (8 min avg, stdev=1) and recovery (12 min avg, stdev=2) in heavier seas (up to sea state 5), as routinely experienced in the South Pacific during the austral winter. In addition to the enhanced safety aspect of having two compatible submersibles aboard, scientific efficiency has benefited by allowing the rotation of vehicles on extended deployments prior to battery servicing, thus maintaining an overall dive time average of 7.1 hr (stdev=1.52) for an average dive depth of 891 m (stdev=431) in 2005. Having the two fully operational submersibles also provides a contingency for equipment malfunction while on site that saved 7 dive days in 2005 alone

  15. Realized niche width of a brackish water submerged aquatic vegetation under current environmental conditions and projected influences of climate change.

    PubMed

    Kotta, Jonne; Möller, Tiia; Orav-Kotta, Helen; Pärnoja, Merli

    2014-12-01

    Little is known about how organisms might respond to multiple climate stressors and this lack of knowledge limits our ability to manage coastal ecosystems under contemporary climate change. Ecological models provide managers and decision makers with greater certainty that the systems affected by their decisions are accurately represented. In this study Boosted Regression Trees modelling was used to relate the cover of submerged aquatic vegetation to the abiotic environment in the brackish Baltic Sea. The analyses showed that the majority of the studied submerged aquatic species are most sensitive to changes in water temperature, current velocity and winter ice scour. Surprisingly, water salinity, turbidity and eutrophication have little impact on the distributional pattern of the studied biota. Both small and large scale environmental variability contributes to the variability of submerged aquatic vegetation. When modelling species distribution under the projected influences of climate change, all of the studied submerged aquatic species appear to be very resilient to a broad range of environmental perturbation and biomass gains are expected when seawater temperature increases. This is mainly because vegetation develops faster in spring and has a longer growing season under the projected climate change scenario. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Water-Level Reconstruction and its Implications for Late Pleistocene Paleontological Site Formation in Hoyo Negro, a Submerged Subterranean Pit in Quintana Roo, Mexico

    NASA Astrophysics Data System (ADS)

    Rissolo, D.; Reinhardt, E. G.; Collins, S.; Kovacs, S. E.; Beddows, P. A.; Chatters, J. C.; Nava Blank, A.; Luna Erreguerena, P.

    2014-12-01

    A massive pit deep within the now submerged cave system of Sac Actun, located along the central east coast of the Yucatan Peninsula, contains a diverse fossil assemblage of extinct megafauna as well as a nearly complete human skeleton. The inundated site of Hoyo Negro presents a unique and promising opportunity for interdisciplinary Paleoamerican and paleoenvironmental research in the region. Investigations have thus far revealed a range of associated features and deposits which make possible a multi-proxy approach to identifying and reconstructing the natural and cultural processes that have formed and transformed the site over millennia. Understanding water-level fluctuations (both related to, and independent from, eustatic sea level changes), with respect to cave morphology is central to understanding the movement of humans and animals into and through the cave system. Recent and ongoing studies involve absolute dating of human, faunal, macrobotanical, and geological samples; taphonomic analyses; and a characterization of site hydrogeology and sedimentological facies, including microfossil assemblages and calcite raft deposits.

  17. [Applied study of the submerged macrophytes bed-immobilized bacteria in drinking water restoration].

    PubMed

    Chen, Qi-Chun; Li, Zheng-Kui; Wang, Yi-Chao; Wu, Kai; Fan, Nian-Wen

    2012-01-01

    The effect of submerged macrophytes bed-immobilized bacteria technology which applied in drinking water restoration was studied. Ammonifying bacteria, nitrobacteria, nitrosobacteria and denitrifying bacteria which isolated from Taihu Labe was immobilized to the porous carries, combined with the submerged macrophytes bed technology, we applied the new equipment in water restoration of gonghu bay, this equipment has good ability to resist storm, the denitrifying bacteria number increased from 5.4 x 10(2)-2.7 x 10(3) to 3.9 x 10(5)-9.1 x 10(5), N2O flux of experimental plot was 3-24 microg x (m2 x h)(-1), it's more than the contrast group obviously, TN concentration reduced 19% - 74%, while NO3- concentration reduced 24% -81% after the equipment running a period of time; The experimental data of 120 days showed that this technology is suitable for drinking water restoration, as it can control eutrophication.

  18. Ergot alkaloids produced by submerged cultures of Claviceps zizaniae.

    PubMed

    Kantorová, Michaela; Kolínská, Renata; Pazoutová, Sylvie; Honzátko, Ales; Havlícek, Vladimír; Flieger, Miroslav

    2002-07-01

    Two ergopeptine alkaloids, alpha-ergocryptine (1) and its C(8) epimer alpha-ergocryptinine, have been isolated from the mycelium and fermentation broth of submerged cultures of Claviceps zizaniae CCM 8240. The structure of 1 was determined by HPLC/positive ion APCI MS and NMR analysis. Alkaloid concentrations of 10 microg/mL in 14-day-old fermentation broth and 1 mg/g of dry mycelium mass were found. These results are of considerable biotechnological interest since these were the only detectable alkaloids produced. Toxicity of naturally occurring sclerotia of C. zizaniae cannot be excluded.

  19. 46 CFR 28.515 - Submergence test as an alternative to stability calculations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... vessel must float with the lower end of the vessel not more than 12 inches (0.31 meters) below the water... described in paragraph (e) of this section must float in calm water, after being submerged for 18 hours, so that— (1) For an open vessel, any portion of the vessel's gunwale is above the water's surface; or (2...

  20. Near-Field Propagation of Sub-Nanosecond Electric Pulses into Amorphous Masses

    DTIC Science & Technology

    2012-02-01

    the Idaho National Engineering Laboratory, Idaho Falls, ID, as a Senior Research Engineer, involved with fission reactor diagnostic measurements. He...temperature probe tip was just submerged in the cell buffer, less than 1 mm deep. For other positions, the maximum temperatures decreased to 34 ± 1 ◦C...422, Apr. 2008. [21] R. P. Joshi, J. Song, K. H. Schoenbach, and V. Sridhara, “Aspects of lipid membrane bio -responses to subnanosecond, ultrahigh

  1. Photoinhibition-like damage to the photosynthetic apparatus in plant leaves induced by submergence treatment in the dark.

    PubMed

    Fan, Xingli; Zhang, Zishan; Gao, Huiyuan; Yang, Cheng; Liu, Meijun; Li, Yuting; Li, Pengmin

    2014-01-01

    Submergence is a common type of environmental stress for plants. It hampers survival and decreases crop yield, mainly by inhibiting plant photosynthesis. The inhibition of photosynthesis and photochemical efficiency by submergence is primarily due to leaf senescence and excess excitation energy, caused by signals from hypoxic roots and inhibition of gas exchange, respectively. However, the influence of mere leaf-submergence on the photosynthetic apparatus is currently unknown. Therefore, we studied the photosynthetic apparatus in detached leaves from four plant species under dark-submergence treatment (DST), without influence from roots and light. Results showed that the donor and acceptor sides, the reaction center of photosystem II (PSII) and photosystem I (PSI) in leaves were significantly damaged after 36 h of DST. This is a photoinhibition-like phenomenon similar to the photoinhibition induced by high light, as further indicated by the degradation of PsaA and D1, the core proteins of PSI and PSII. In contrast to previous research, the chlorophyll content remained unchanged and the H2O2 concentration did not increase in the leaves, implying that the damage to the photosynthetic apparatus was not caused by senescence or over-accumulation of reactive oxygen species (ROS). DST-induced damage to the photosynthetic apparatus was aggravated by increasing treatment temperature. This type of damage also occurred in the anaerobic environment (N2) without water, and could be eliminated or restored by supplying air to the water during or after DST. Our results demonstrate that DST-induced damage was caused by the hypoxic environment. The mechanism by which DST induces the photoinhibition-like damage is discussed below.

  2. Photoinhibition-Like Damage to the Photosynthetic Apparatus in Plant Leaves Induced by Submergence Treatment in the Dark

    PubMed Central

    Gao, Huiyuan; Yang, Cheng; Liu, Meijun; Li, Yuting; Li, Pengmin

    2014-01-01

    Submergence is a common type of environmental stress for plants. It hampers survival and decreases crop yield, mainly by inhibiting plant photosynthesis. The inhibition of photosynthesis and photochemical efficiency by submergence is primarily due to leaf senescence and excess excitation energy, caused by signals from hypoxic roots and inhibition of gas exchange, respectively. However, the influence of mere leaf-submergence on the photosynthetic apparatus is currently unknown. Therefore, we studied the photosynthetic apparatus in detached leaves from four plant species under dark-submergence treatment (DST), without influence from roots and light. Results showed that the donor and acceptor sides, the reaction center of photosystem II (PSII) and photosystem I (PSI) in leaves were significantly damaged after 36 h of DST. This is a photoinhibition-like phenomenon similar to the photoinhibition induced by high light, as further indicated by the degradation of PsaA and D1, the core proteins of PSI and PSII. In contrast to previous research, the chlorophyll content remained unchanged and the H2O2 concentration did not increase in the leaves, implying that the damage to the photosynthetic apparatus was not caused by senescence or over-accumulation of reactive oxygen species (ROS). DST-induced damage to the photosynthetic apparatus was aggravated by increasing treatment temperature. This type of damage also occurred in the anaerobic environment (N2) without water, and could be eliminated or restored by supplying air to the water during or after DST. Our results demonstrate that DST-induced damage was caused by the hypoxic environment. The mechanism by which DST induces the photoinhibition-like damage is discussed below. PMID:24586508

  3. Resonant vibrations of a submerged beam

    NASA Astrophysics Data System (ADS)

    Achenbach, J. D.; Qu, J.

    1986-03-01

    Forced vibration of a simply supported submerged beam of circular cross section is investigated by the use of two mathematical methods. In the first approach the problem formulation is reduced to a singular integro-differential equation for the transverse deflection. In the second approach the method of matched asymptotic expansions is employed. The integro-differential equation is solved numerically, to yield an exact solution for the frequency response. Subsequent use of a representation integral yields the radiated far field acoustic pressure. The exact results for the beam deflection are compared with approximate results that are available in the literature. Next, a matched asymptotic expansion is worked out by constructing "inner" and "outer" expansions for frequencies near and not near resonance frequencies, respectively. The two expansions are matched in an appropriate manner to yield a uniformly valid solution. The leading term of the matched asymptotic solution is compared with exact numerical results.

  4. Acoustic radiation from the submerged circular cylindrical shell treated with active constrained layer damping

    NASA Astrophysics Data System (ADS)

    Yuan, Li-Yun; Xiang, Yu; Lu, Jing; Jiang, Hong-Hua

    2015-12-01

    Based on the transfer matrix method of exploring the circular cylindrical shell treated with active constrained layer damping (i.e., ACLD), combined with the analytical solution of the Helmholtz equation for a point source, a multi-point multipole virtual source simulation method is for the first time proposed for solving the acoustic radiation problem of a submerged ACLD shell. This approach, wherein some virtual point sources are assumed to be evenly distributed on the axial line of the cylindrical shell, and the sound pressure could be written in the form of the sum of the wave functions series with the undetermined coefficients, is demonstrated to be accurate to achieve the radiation acoustic pressure of the pulsating and oscillating spheres respectively. Meanwhile, this approach is proved to be accurate to obtain the radiation acoustic pressure for a stiffened cylindrical shell. Then, the chosen number of the virtual distributed point sources and truncated number of the wave functions series are discussed to achieve the approximate radiation acoustic pressure of an ACLD cylindrical shell. Applying this method, different radiation acoustic pressures of a submerged ACLD cylindrical shell with different boundary conditions, different thickness values of viscoelastic and piezoelectric layer, different feedback gains for the piezoelectric layer and coverage of ACLD are discussed in detail. Results show that a thicker thickness and larger velocity gain for the piezoelectric layer and larger coverage of the ACLD layer can obtain a better damping effect for the whole structure in general. Whereas, laying a thicker viscoelastic layer is not always a better treatment to achieve a better acoustic characteristic. Project supported by the National Natural Science Foundation of China (Grant Nos. 11162001, 11502056, and 51105083), the Natural Science Foundation of Guangxi Zhuang Autonomous Region, China (Grant No. 2012GXNSFAA053207), the Doctor Foundation of Guangxi

  5. Project DEEP STEAM

    NASA Astrophysics Data System (ADS)

    Aeschliman, D. P.; Clay, R. G.; Donaldson, A. B.; Eisenhawer, S. W.; Fox, R. L.; Johnson, D. R.; Mulac, A. J.

    1982-01-01

    The objective of Project DEEP STEAM is to develop the technology to economically produce heavy oils from deep reservoirs. The tasks included in this project are the development of thermally efficient delivery systems and downhole steam generation systems. During the period January 1-March 31, 1981, effort has continued on a low pressure combustion downhole generator (Rocketdyne), and on two high pressure designs (Foster-Miller Associates, Sandia National Laboratories). The Sandia design was prepared for deployment in the Wilmington Field at Long Beach, California. Progress continued on the Min-Stress II packer concept at L'Garde, Inc., and on the extruded metal packer at Foster-Miller. Initial bare string field data are reported on the insulated tubular test at Lloydminster, Saskatchewan, Canada.

  6. 77 FR 12245 - Deep Seabed Mining: Request for Extension of Exploration Licenses

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-29

    ... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration Deep Seabed Mining: Request.... Department of Commerce. ACTION: Notice of receipt of application to extend Deep Seabed Mining Exploration... received an application for five-year extensions of Deep Seabed Mining Exploration Licenses USA-1 and USA-4...

  7. Satellite remote sensing of submerged aquatic vegetation distribution and status in the Currituck Sound, NC.

    DOT National Transportation Integrated Search

    2012-11-01

    Submerged Aquatic Vegetation (SAV) is an important component in any estuarine ecosystem. As such, it is regulated by federal and state agencies as a jurisdictional resource, where impacts to SAV are compensated through mitigation. Historically, tradi...

  8. Comparative evaluation of extracellular β-D-fructofuranosidase in submerged and solid-state fermentation produced by newly identified Bacillus subtilis strain.

    PubMed

    Lincoln, Lynette; More, Sunil S

    2018-04-17

    To screen and identify a potential extracellular β-D-fructofuranosidase or invertase producing bacterium from soil, and comparatively evaluate the enzyme biosynthesis under submerged and solid-state fermentation. Extracellular invertase producing bacteria were screened from soil. Identification of the potent bacterium was performed based on microscopic examinations and 16S rDNA molecular sequencing. Bacillus subtilis LYN12 invertase secretion was surplus with wheat bran humidified with molasses medium (70%), with elevated activity at 48 h and 37 °C under solid-state fermentation, whereas under submerged conditions increased activity was observed at 24 h and 45 °C in the molasses medium. The study revealed a simple fermentative medium for elevated production of extracellular invertase from a fast growing Bacillus strain. Bacterial invertases are scarce and limited reports are available. By far, this is the first report on the comparative analysis of optimization of extracellular invertase synthesis from Bacillus subtilis strain by submerged and solid-state fermentation. The use of agricultural residues increased yields resulting in development of a cost-effective and stable approach. Bacillus subtilis LYN12 invertase possesses excellent fermenting capability to utilize agro-industrial residues under submerged and solid-state conditions. This could be a beneficial candidate in food and beverage processing industries. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  9. DEEP: Database of Energy Efficiency Performance

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hong, Tianzhen; Piette, Mary; Lee, Sang Hoon

    A database of energy efficiency performance (DEEP) is a presimulated database to enable quick and accurate assessment of energy retrofit of commercial buildings. DEEP was compiled from results of about 10 million EnergyPlus simulations. DEEP provides energy savings for screening and evaluation of retrofit measures targeting the small and medium-sized office and retail buildings in California. The prototype building models are developed for a comprehensive assessment of building energy performance based on DOE commercial reference buildings and the California DEER [sic] prototype buildings. The prototype buildings represent seven building types across six vintages of constructions and 16 California climate zones.more » DEEP uses these prototypes to evaluate energy performance of about 100 energy conservation measures covering envelope, lighting, heating, ventilation, air conditioning, plug loads, and domestic hot war. DEEP consists the energy simulation results for individual retrofit measures as well as packages of measures to consider interactive effects between multiple measures. The large scale EnergyPlus simulations are being conducted on the super computers at the National Energy Research Scientific Computing Center (NERSC) of Lawrence Berkeley National Laboratory. The pre-simulation database is a part of the CEC PIER project to develop a web-based retrofit toolkit for small and medium-sized commercial buildings in California, which provides real-time energy retrofit feedback by querying DEEP with recommended measures, estimated energy savings and financial payback period based on users' decision criteria of maximizing energy savings, energy cost savings, carbon reduction, or payback of investment. The pre-simulated database and associated comprehensive measure analysis enhances the ability to performance assessments of retrofits to reduce energy use for small and medium buildings and business owners who typically do not have resources to conduct costly

  10. Captive bubble and sessile drop surface characterization of a submerged aquatic plant, Hydrilla verticillata

    USDA-ARS?s Scientific Manuscript database

    The surface energy parameters of the invasive aquatic weed, Hydrilla verticillata, were determined using contact angle measurements using two different methods. The abaxial and adaxial surfaces of the leaves and stem were characterized for the weed while submerged in water using captive air and octa...

  11. Optimization of submerged depth of surface aerators for a carrousel oxidation ditch based on large eddy simulation with Smagorinsky model.

    PubMed

    Wei, Wenli; Bai, Yu; Liu, Yuling

    2016-01-01

    This paper is concerned with the simulation and experimental study of hydraulic characteristics in a pilot Carrousel oxidation ditch for the optimization of submerged depth ratio of surface aerators. The simulation was based on the large eddy simulation with the Smagorinsky model, and the velocity was monitored in the ditches with an acoustic Doppler velocimeter method. Comparisons of the simulated velocities and experimental ones show a good agreement, which validates that the accuracy of this simulation is good. The best submerged depth ratio of 2/3 for surface aerators was obtained according to the analysis of the flow field structure, the ratio of gas and liquid in the bottom layer of a ditch, the average velocity of mixture and the flow region with a velocity easily causing sludge deposition under the four operation conditions with submerged depth ratios of 1/3, 1/2, 2/3 and 3/4 for surface aerators. The research result can provide a reference for the design of Carrousel oxidation ditches.

  12. Deep Borehole Field Test Research Activities at LBNL

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dobson, Patrick; Tsang, Chin-Fu; Kneafsey, Timothy

    The goal of the U.S. Department of Energy Used Fuel Disposition’s (UFD) Deep Borehole Field Test is to drill two 5 km large-diameter boreholes: a characterization borehole with a bottom-hole diameter of 8.5 inches and a field test borehole with a bottom-hole diameter of 17 inches. These boreholes will be used to demonstrate the ability to drill such holes in crystalline rocks, effectively characterize the bedrock repository system using geophysical, geochemical, and hydrological techniques, and emplace and retrieve test waste packages. These studies will be used to test the deep borehole disposal concept, which requires a hydrologically isolated environment characterizedmore » by low permeability, stable fluid density, reducing fluid chemistry conditions, and an effective borehole seal. During FY16, Lawrence Berkeley National Laboratory scientists conducted a number of research studies to support the UFD Deep Borehole Field Test effort. This work included providing supporting data for the Los Alamos National Laboratory geologic framework model for the proposed deep borehole site, conducting an analog study using an extensive suite of geoscience data and samples from a deep (2.5 km) research borehole in Sweden, conducting laboratory experiments and coupled process modeling related to borehole seals, and developing a suite of potential techniques that could be applied to the characterization and monitoring of the deep borehole environment. The results of these studies are presented in this report.« less

  13. New records of the deep-sea anemone Phelliactis callicyclus Riemann-Zurneck, 1973 (Cnidaria, Actiniaria, Hormathiidae) from the Gulf of California, Mexico.

    PubMed

    Hendrickx, M E; Hinojosa-Corona, A; Ayón-Parente, M

    2016-10-20

    Specimens of a deep-sea anemone were observed in photographs and video footage taken with the Remotely Operated Vehicle JASON (WHOI Deep Submergence Laboratory) in the Gulf of California, Mexico, in May 2008. Comparison of our material with photographs and description of this species available in literature indicate that the sea anemones filmed during the JASON survey are most likely to represent Phelliactis callicyclus Riemann-Zurneck, 1973. This species has previously been reported from a locality in the Gulf of California near the present record. During the JASON survey, 28 specimens of P. callicyclus were spotted in 27 locations during six dives. The specimens occurred on angular rock outcrops along the escarpments of the transform faults of the Gulf of California, between depths of 993-2543 m and at temperatures ranging from 2.3 to 4.5°C. Based on these new records, Phelliactis callicyclus appears to be widely spread in the Gulf of California.

  14. Photosynthesis of amphibious and obligately submerged plants in CO2-rich lowland streams.

    PubMed

    Sand-Jensen, Kaj; Frost-Christensen, Henning

    1998-11-01

    Small unshaded streams in lowland regions receive drainage water with high concentrations of free␣CO 2 , and they support an abundant growth of amphibious and obligately submerged plants. Our first objective was to measure the CO 2 regime during summer in a wide range of small alkaline Danish streams subject to wide variation in temperature, O 2 and CO 2 during the day. The second objective was to determine the effect of these variations on daily changes in light-saturated photosynthesis in water of a homophyllous and a heterophyllous amphibious species that only used CO 2 , and an obligately submerged species capable of using both HCO - 3 and CO 2 . We found that the median CO 2 concentrations of the streams were 11 and 6 times above air saturation in the morning and the afternoon, respectively, but stream sites with dense plant growth had CO 2 concentrations approaching air saturation in the afternoon. In contrast, outlets from lakes had low CO 2 concentrations close to, or below, air saturation. The amphibious species showed a reduction of photosynthesis in water from morning to afternoon along with the decline in CO 2 concentrations, while increasing temperature and O 2 had little effect on photosynthesis. Photosynthesis of the obligately submerged species varied little with the change of CO 2 because of HCO 3 - - use, and variations were mostly due to changes in O 2 concentration. Independent measurements showed that changes in temperature, O 2 and CO 2 could account for the daily variability of photosynthesis of all three species in water. The results imply that CO 2 supersaturation in small lowland streams is important for the rich representation of amphibious species and their contribution to system photosynthesis.

  15. Morphologic and seismic evidence of rapid submergence offshore Cide-Sinop in the southern Black Sea shelf

    NASA Astrophysics Data System (ADS)

    Ocakoğlu, Neslihan; İşcan, Yeliz; Kılıç, Fatmagül; Özel, Oğuz

    2018-06-01

    Multi-beam bathymetric and multi-channel seismic reflection data obtained offshore Cide-Sinop have revealed important records on the latest transgression of the Black Sea for the first time. A relatively large shelf plain within the narrow southern continental shelf characterized by a flat seafloor morphology at -100 water depth followed by a steep continental slope leading to -500 m depth. This area is widely covered by submerged morphological features such as dunes, lagoons, possible aeolianites, an eroded anticline and small channels that developed by aeolian and fluvial processes. These morphological features sit upon an erosional surface that truncates the top of all seismic units and constitutes the seafloor over the whole shelf. The recent prograded delta deposits around the shelf break are also truncated by the similar erosional surface. These results indicate that offshore Cide-Sinop was once a terrestrial landscape that was then submerged. The interpreted paleoshoreline varies from -100 to -120 m. This variation can be explained by not only sea level changes but also the active faults observed on the seismic section. The effective protection of morphological features on the seafloor is the evidence of abrupt submergence rather than gradual. In addition, the absence of coastal onlaps suggests that these morphological features should have developed at low sea level before the latest sea level rise in the Black Sea.

  16. Transcriptional and Enzymatic Profiling of Pleurotus ostreatus Laccase Genes in Submerged and Solid-State Fermentation Cultures

    PubMed Central

    Castanera, Raúl; Pérez, Gúmer; Omarini, Alejandra; Alfaro, Manuel; Pisabarro, Antonio G.; Faraco, Vincenza; Amore, Antonella

    2012-01-01

    The genome of the white rot basidiomycete Pleurotus ostreatus includes 12 phenol oxidase (laccase) genes. In this study, we examined their expression profiles in different fungal strains under different culture conditions (submerged and solid cultures) and in the presence of a wheat straw extract, which was used as an inducer of the laccase gene family. We used a reverse transcription-quantitative PCR (RT-qPCR)-based approach and focused on determining the reaction parameters (in particular, the reference gene set for the normalization and reaction efficiency determinations) used to achieve an accurate estimation of the relative gene expression values. The results suggested that (i) laccase gene transcription is upregulated in the induced submerged fermentation (iSmF) cultures but downregulated in the solid fermentation (SSF) cultures, (ii) the Lacc2 and Lacc10 genes are the main sources of laccase activity in the iSmF cultures upon induction with water-soluble wheat straw extracts, and (iii) an additional, as-yet-uncharacterized activity (Unk1) is specifically induced in SSF cultures that complements the activity of Lacc2 and Lacc10. Moreover, both the enzymatic laccase activities and the Lacc gene family transcription profiles greatly differ between closely related strains. These differences can be targeted for biotechnological breeding programs for enzyme production in submerged fermentation reactors. PMID:22467498

  17. A submerged singularity method for calculating potential flow velocities at arbitrary near-field points

    NASA Technical Reports Server (NTRS)

    Maskew, B.

    1976-01-01

    A discrete singularity method has been developed for calculating the potential flow around two-dimensional airfoils. The objective was to calculate velocities at any arbitrary point in the flow field, including points that approach the airfoil surface. That objective was achieved and is demonstrated here on a Joukowski airfoil. The method used combined vortices and sources ''submerged'' a small distance below the airfoil surface and incorporated a near-field subvortex technique developed earlier. When a velocity calculation point approached the airfoil surface, the number of discrete singularities effectively increased (but only locally) to keep the point just outside the error region of the submerged singularity discretization. The method could be extended to three dimensions, and should improve nonlinear methods, which calculate interference effects between multiple wings, and which include the effects of force-free trailing vortex sheets. The capability demonstrated here would extend the scope of such calculations to allow the close approach of wings and vortex sheets (or vortices).

  18. A model for the release, dispersion and environmental impact of a postulated reactor accident from a submerged commercial nuclear power plant

    NASA Astrophysics Data System (ADS)

    Bertch, Timothy Creston

    1998-12-01

    Nuclear power plants are inherently suitable for submerged applications and could provide power to the shore power grid or support future underwater applications. The technology exists today and the construction of a submerged commercial nuclear power plant may become desirable. A submerged reactor is safer to humans because the infinite supply of water for heat removal, particulate retention in the water column, sedimentation to the ocean floor and inherent shielding of the aquatic environment would significantly mitigate the effects of a reactor accident. A better understanding of reactor operation in this new environment is required to quantify the radioecological impact and to determine the suitability of this concept. The impact of release to the environment from a severe reactor accident is a new aspect of the field of marine radioecology. Current efforts have been centered on radioecological impacts of nuclear waste disposal, nuclear weapons testing fallout and shore nuclear plant discharges. This dissertation examines the environmental impact of a severe reactor accident in a submerged commercial nuclear power plant, modeling a postulated site on the Atlantic continental shelf adjacent to the United States. This effort models the effects of geography, decay, particle transport/dispersion, bioaccumulation and elimination with associated dose commitment. The use of a source term equivalent to the release from Chernobyl allows comparison between the impacts of that accident and the postulated submerged commercial reactor plant accident. All input parameters are evaluated using sensitivity analysis. The effect of the release on marine biota is determined. Study of the pathways to humans from gaseous radionuclides, consumption of contaminated marine biota and direct exposure as contaminated water reaches the shoreline is conducted. The model developed by this effort predicts a significant mitigation of the radioecological impact of the reactor accident release

  19. Observation of pressure variation in the cavitation region of submerged journal bearings

    NASA Technical Reports Server (NTRS)

    Etsion, I.; Ludwig, L. P.

    1980-01-01

    Visual observations and pressure measurements in the cavitation zone of a submerged journal bearing are described. Tests were performed at various shaft speeds and ambient pressure levels. Some photographs of the cavitation region are presented showing strong reverse flow at the downstream end of the region. Pressure profiles are presented showing significant pressure variations inside the cavitation zone, contrary to common assumptions of constant cavitation pressure.

  20. INNOVATIVE TECHNOLOGY EVALUATION REPORT, SEDIMENT SAMPLING TECHNOLOGY, ART'S MANUFACTURING, SPLIT CORE SAMPLER FOR SUBMERGED SEDIMENTS

    EPA Science Inventory


    The Split Core Sampler for Submerged Sediments (Split Core Sampler) designed and fabricated by Arts Manufacturing & Supply, Inc., was demonstrated under the U.S. Environmental Protection Agency (EPA) Superfund Innovative Technology Evaluation Program in April and May 1999 at ...

  1. A new mechanism of macrophyte mitigation: how submerged plants reduce malathion's acute toxicity to aquatic animals.

    PubMed

    Brogan, William R; Relyea, Rick A

    2014-08-01

    A growing body of evidence suggests that aquatic plants can mitigate the toxicity of insecticides to sensitive aquatic animals. The current paradigm is that this ability is driven primarily by insecticide sorption to plant tissues, especially for hydrophobic compounds. However, recent work shows that submerged plants can strongly mitigate the toxicity of the relatively hydrophilic insecticide malathion, despite the fact that this compound exhibits a slow sorption rate to plants. To examine this disparity, we tested the hypothesis that the mitigating effect of submerged plants on malathion's toxicity is driven primarily by the increased water pH from plant photosynthesis causing the hydrolysis of malathion, rather than by sorption. To do this, we compared zooplankton (Daphnia magna) survival across five environmentally relevant malathion concentrations (0, 1, 4, 6, or 36 μg L(-1)) in test containers where we chemically manipulated water pH in the absence of plants or added the submerged plant (Elodea canadensis) but manipulated plant photosynthetic activity via shading or no shading. We discovered that malathion was equally lethal to Daphnia at all concentrations tested when photosynthetically inactive (i.e. shaded) plants were present (pH at time of dosing=7.8) or when pH was chemically decreased (pH=7.7). In contrast, when photosynthetically active (i.e. unshaded) plants were present (pH=9.8) or when pH was chemically increased (pH=9.5), the effects of 4 and 6 μg L(-1) of malathion on Daphnia were mitigated strongly and to an equal degree. These results demonstrate that the mitigating effect of submerged plants on malathion's toxicity can be explained entirely by a mechanism of photosynthesizing plants causing an increase in water pH, resulting in rapid malathion hydrolysis. Our findings suggest that current ecotoxicological models and phytoremediation strategies may be overlooking a critical mechanism for mitigating pesticides. Copyright © 2014 Elsevier Ltd

  2. Depth Estimation of Submerged Aquatic Vegetation in Clear Water Streams Using Low-Altitude Optical Remote Sensing.

    PubMed

    Visser, Fleur; Buis, Kerst; Verschoren, Veerle; Meire, Patrick

    2015-09-30

    UAVs and other low-altitude remote sensing platforms are proving very useful tools for remote sensing of river systems. Currently consumer grade cameras are still the most commonly used sensors for this purpose. In particular, progress is being made to obtain river bathymetry from the optical image data collected with such cameras, using the strong attenuation of light in water. No studies have yet applied this method to map submergence depth of aquatic vegetation, which has rather different reflectance characteristics from river bed substrate. This study therefore looked at the possibilities to use the optical image data to map submerged aquatic vegetation (SAV) depth in shallow clear water streams. We first applied the Optimal Band Ratio Analysis method (OBRA) of Legleiter et al. (2009) to a dataset of spectral signatures from three macrophyte species in a clear water stream. The results showed that for each species the ratio of certain wavelengths were strongly associated with depth. A combined assessment of all species resulted in equally strong associations, indicating that the effect of spectral variation in vegetation is subsidiary to spectral variation due to depth changes. Strongest associations (R²-values ranging from 0.67 to 0.90 for different species) were found for combinations including one band in the near infrared (NIR) region between 825 and 925 nm and one band in the visible light region. Currently data of both high spatial and spectral resolution is not commonly available to apply the OBRA results directly to image data for SAV depth mapping. Instead a novel, low-cost data acquisition method was used to obtain six-band high spatial resolution image composites using a NIR sensitive DSLR camera. A field dataset of SAV submergence depths was used to develop regression models for the mapping of submergence depth from image pixel values. Band (combinations) providing the best performing models (R²-values up to 0.77) corresponded with the OBRA

  3. Distribution of submerged aquatic vegetation in the St. Louis River estuary: Maps and models

    EPA Science Inventory

    In late summer of 2011 and 2012 we used echo-sounding gear to map the distribution of submerged aquatic vegetation (SAV) in the St. Louis River Estuary (SLRE). From these data we produced maps of SAV distribution and we created logistic models to predict the probability of occurr...

  4. Hydrodynamic Behaviour of Fully and Partially Submerged Plants In Open Channel Flow: A Prototype Scale Experiment.

    NASA Astrophysics Data System (ADS)

    Armanini, A.; Bortoluzzi, D.; Grisenti, P.; Righetti, M.

    The hydrodynamic behaviour of partially and fully submerged tall vegetation is of great interest in the river management. Only recently some researchers (Kouwen, 1999, Oplatka, 1998) analyzed the hydrodynamic resistance of bushes, taking into account also the plants elasticity in the classical Petryk & Bosmajian approach. In the present work, an experimental investigation is performed, where the hydrodynamic resistance of isolated and grouped salix alba bushes is measured, in a laboratory chan- nel at prototype scale. This kind of plants has particular interest because they are often used in bank stabilization and remediation works for mountain streams. The tests are performed using young plants, ranging from 1 m up to 2 m high, in a 100 m long, 2 m deep and 2 m large open channel flow, the discharge ranges up to 1,3 m3/sec. A suitable strain gauges system has been realized in order to directly measure the force exerted on the plant by the flow. The results are compared with analogous measure- ments of Oplatka and Kouwen, confirming the influence of elasticity and leaves on hydrodynamic resistance; in particular the effect of smaller branches bending and the influence of foliage on drag has been analyzed, comparing the drag of the same bush with and without leaves. Moreover an approach for drag evaluation, alternative to that of Oplatka and Kouwen is proposed.

  5. A Deep-Ocean Observatory with Near Real-time Telemetry

    NASA Astrophysics Data System (ADS)

    Berger, J.; Orcutt, J. A.; Laske, G.

    2014-12-01

    We describe an autonomously deployable, deep-ocean observatory designed to provide long term and near-real-time observations from sites far offshore. The key feature of this new system is its ability to telemeter sensor data from the seafloor to shore without a cable or moored surface buoy. In the future the observatory will be deployable without a ship. The first application of this system is seismology. While permanent ocean seismic stations on the seafloor have long been a goal of global seismology, today there are still no ocean bottom stations in the Global Seismographic Network, mostly for reasons of life-cycle costs. Yet real-time data from stations in oceanic areas are critical for both national and international agencies in monitoring and characterizing earthquakes, tsunamis, and nuclear explosions. The system comprises an ocean bottom instrumentation package and a free-floating surface communications gateway, which uses a Liquid Robotics wave glider. The glider consists of a surfboard-sized float propelled by a tethered, submerged glider, which converts wave motion into thrust. For navigation, the wave gliders are equipped with a small computer, a GPS receiver, a rudder, solar panels and batteries, and an Iridium satellite modem. Wave gliders have demonstrated trans-oceanic range combined with long-term station holding. The 'communications gateway,' which provides the means of communicating between the ocean bottom package and land comprises a wave glider and a towed acoustic communications 'tow body'. Acoustic communications connect the subsea instruments and the surface gateway while communications between the gateway and land is provided by the Iridium satellite constellation. Tests of the surface gateway in 4350 m of water demonstrated the ability to send four channels of compressed 24-bit, 1 sample per second data from the ocean bottom to the gateway with an average power draw of approximately 0.2 W.

  6. Sea Level Affecting Marshes Model (SLAMM)‐New Functionality for Predicting Changes in Distribution of Submerged Aquatic Vegetation in Response to Sea Level Rise.Version 1.0

    EPA Science Inventory

    Submerged aquatic vegetation (SAV) is an ecologically important habitat world-wide. In Pacific Northwest (PNW) estuaries, SAV in the lower intertidal and shallow subtidal habitats are dominated by the native seagrass, Zostera marina also referred to as submerged aquatic vegetati...

  7. Ultra-Deep Drilling Cost Reduction; Design and Fabrication of an Ultra-Deep Drilling Simulator (UDS)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lindstrom, Jason

    2010-01-31

    Ultra-deep drilling, below about 20,000 ft (6,096 m), is extremely expensive and limits the recovery of hydrocarbons at these depths. Unfortunately, rock breakage and cuttings removal under these conditions is not understood. To better understand and thus reduce cost at these conditions an ultra-deep single cutter drilling simulator (UDS) capable of drill cutter and mud tests to sustained pressure and temperature of 30,000 psi (207 MPa) and 482 °F (250 °C), respectively, was designed and manufactured at TerraTek, a Schlumberger company, in cooperation with the Department of Energy’s National Energy Technology Laboratory. UDS testing under ultra-deep drilling conditions offers anmore » economical alternative to high day rates and can prove or disprove the viability of a particular drilling technique or fluid to provide opportunity for future domestic energy needs.« less

  8. The Hawai'i Undersea Research Laboratory: Applying Innovative Deep-sea Technologies Toward Research, Service, and Stewardship in Marine Protected Areas of the Pacific Region

    NASA Astrophysics Data System (ADS)

    Smith, J. R.

    2012-12-01

    The Hawai'i Undersea Research Laboratory (HURL) is the only U.S. deep submergence facility in the Pacific Rim tasked with supporting undersea research necessary to fulfill the mission, goals, and objectives of the National Oceanic and Atmospheric Administration (NOAA), along with other national interests of importance. Over 30 years of submersible operations have resulted in nearly 1900 dives representing 9300 hours underwater, and a benthic ecology database derived from in-house video record logging of over 125,000 entries based on 1100 unique deep-sea animal identifications in the Hawaiian Archipelago. As a Regional Center within the Office of Ocean Exploration and Research (OER), HURL conducts undersea research in offshore and nearshore waters of the main and Northwestern Hawaiian Islands and waters of the central, southern, and western Pacific. HURL facilities primarily support marine research projects that require data acquisition at depths greater than wet diving methods. These consist of the research vessel Ka'imikai-o-Kanaloa (KOK), human occupied submersibles Pisces IV and Pisces V (2000 m), a new remotely operated vehicle (6000 m), and a multibeam bathymetric sonar system (11,000 m). In addition, HURL has also supported AAUS compliant wet diving since 2003, including technical mixed gas/rebreather work. While ecosystem studies of island, atoll, and seamount flanks are the largest component of the HURL science program, many other thematic research areas have been targeted including extreme and unique environments, new resources from the sea, episodic events to long term changes, and the development of innovative technologies. Several examples of HURL's contributions to marine protected areas (MPAs) include: (a) A long term presence in the pristine ecosystems of the Papahānaumokuākea Marine National Monument in the Northwestern Hawaiian Islands. Researchers from National Marine Fisheries have used HURL assets to study endangered Hawaiian Monk Seal habitat

  9. Pulley reef: a deep photosynthetic coral reef on the West Florida Shelf, USA

    USGS Publications Warehouse

    Culter, J.K.; Ritchie, K.B.; Earle, S.A.; Guggenheim, D.E.; Halley, R.B.; Ciembronowicz, K.T.; Hine, A.C.; Jarrett, B.D.; Locker, S.D.; Jaap, W.C.

    2006-01-01

    Pulley Reef (24°50′N, 83°40′W) lies on a submerged late Pleistocene shoreline feature that formed during a sea-level stillstand from 13.8 to 14.5 ka (Jarrett et al. 2005). The reef is currently 60–75 m deep, exhibits 10–60% coral cover, and extends over approximately 160 km2 of the sea floor. Zooxanthellate corals are primarily Agaricia lamarcki, A. fragilis, Leptoseris cucullata, and less common Madracis formosa, M. pharensis, M. decactis, Montastraea cavernosa, Porites divaricata, Scolymia cubensis and Oculina tenella. Coralline algae are comparable in abundance to stony corals. Other macroalgae include Halimeda tuna, Dictyota divaricata, Lobophora variegata, Ventricatri ventricosa, Verdigelas pelas, and Kallymenia sp. Anadyomene menziesii is abundant. The reef provides a habitat for organisms typically observed at much shallower depths, and is the deepest known photosynthetic coral reef on the North America continental shelf (Fig. 1).

  10. 3-D flow and scour near a submerged wing dike: ADCP measurements on the Missouri River

    USGS Publications Warehouse

    Jamieson, E.C.; Rennie, C.D.; Jacobson, R.B.; Townsend, R.D.

    2011-01-01

    Detailed mapping of bathymetry and three-dimensional water velocities using a boat-mounted single-beam sonar and acoustic Doppler current profiler (ADCP) was carried out in the vicinity of two submerged wing dikes located in the Lower Missouri River near Columbia, Missouri. During high spring flows the wing dikes become submerged, creating a unique combination of vertical flow separation and overtopping (plunging) flow conditions, causing large-scale three-dimensional turbulent flow structures to form. On three different days and for a range of discharges, sampling transects at 5 and 20 m spacing were completed, covering the area adjacent to and upstream and downstream from two different wing dikes. The objectives of this research are to evaluate whether an ADCP can identify and measure large-scale flow features such as recirculating flow and vortex shedding that develop in the vicinity of a submerged wing dike; and whether or not moving-boat (single-transect) data are sufficient for resolving complex three-dimensional flow fields. Results indicate that spatial averaging from multiple nearby single transects may be more representative of an inherently complex (temporally and spatially variable) three-dimensional flow field than repeated single transects. Results also indicate a correspondence between the location of calculated vortex cores (resolved from the interpolated three-dimensional flow field) and the nearby scour holes, providing new insight into the connections between vertically oriented coherent structures and local scour, with the unique perspective of flow and morphology in a large river.

  11. Impact of Temperature and Nutrients on Carbon: Nutrient Tissue Stoichiometry of Submerged Aquatic Plants: An Experiment and Meta-Analysis.

    PubMed

    Velthuis, Mandy; van Deelen, Emma; van Donk, Ellen; Zhang, Peiyu; Bakker, Elisabeth S

    2017-01-01

    Human activity is currently changing our environment rapidly, with predicted temperature increases of 1-5°C over the coming century and increased nitrogen and phosphorus inputs in aquatic ecosystems. In the shallow parts of these ecosystems, submerged aquatic plants enhance water clarity by resource competition with phytoplankton, provide habitat, and serve as a food source for other organisms. The carbon:nutrient stoichiometry of submerged aquatic plants can be affected by changes in both temperature and nutrient availability. We hypothesized that elevated temperature leads to higher carbon:nutrient ratios through enhanced nutrient-use efficiency, while nutrient addition leads to lower carbon:nutrient ratios by the luxurious uptake of nutrients. We addressed these hypotheses with an experimental and a meta-analytical approach. We performed a full-factorial microcosm experiment with the freshwater plant Elodea nuttallii grown at 10, 15, 20, and 25°C on sediment consisting of pond soil/sand mixtures with 100, 50, 25, and 12.5% pond soil. To address the effect of climatic warming and nutrient addition on the carbon:nutrient stoichiometry of submerged freshwater and marine plants we performed a meta-analysis on experimental studies that elevated temperature and/or added nutrients (nitrogen and phosphorus). In the microcosm experiment, C:N ratios of Elodea nuttallii decreased with increasing temperature, and this effect was most pronounced at intermediate nutrient availability. Furthermore, higher nutrient availability led to decreased aboveground C:P ratios. In the meta-analysis, nutrient addition led to a 25, 22, and 16% reduction in aboveground C:N and C:P ratios and belowground C:N ratios, accompanied with increased N content. No consistent effect of elevated temperature on plant stoichiometry could be observed, as very few studies were found on this topic and contrasting results were reported. We conclude that while nutrient addition consistently leads to

  12. Lessons from Earth's Deep Time

    ERIC Educational Resources Information Center

    Soreghan, G. S.

    2005-01-01

    Earth is a repository of data on climatic changes from its deep-time history. Article discusses the collection and study of these data to predict future climatic changes, the need to create national study centers for the purpose, and the necessary cooperation between different branches of science in climatic research.

  13. Will heavy metals in the soils of newly submerged areas threaten the water quality of Danjiangkou Reservoir, China?

    PubMed

    Song, Zhixin; Shan, Baoqing; Tang, Wenzhong; Zhang, Chao

    2017-10-01

    Soil heavy metal contents were measured in newly submerged areas of the Danjiangkou Reservoir, China. We aimed to determine the heavy metal distribution in this area and the associated ecological risk. Most of these heavy metal contents (except Pb and Mn) suggest enrichment compared with the background values of soils from Henan Province, especially As and Cd with mean geo-accumulation index (I geo ) values of 0.84 and 0.54. The spatial analysis results indicated that the highest heavy metal contents were distributed in the arable soils above 160m elevation, whereas low heavy metal contents were observed under other land-use types above 160m elevation. According to I geo and EF values, Cd was the major heavy metal contaminant in the newly submerged area, Cr, Pb and Mn mainly originated from natural geochemical sources. In contrast, Ni, Cd, As, Cu, and Zn mainly originated from anthropogenic sources. Evaluation using the potential ecological risk (PER) method indicated that PER of individual elements were low in the studied soils, and the comprehensive PER index was at a moderate level, indicating heavy metals in the soils of newly submerged areas may not threaten the water quality of Danjiangkou Reservoir, especially in winter. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Methane oxidation associated to submerged brown-mosses buffers methane emissions from Siberian polygonal peatlands

    NASA Astrophysics Data System (ADS)

    Liebner, Susanne; Zeyer, Josef; Knoblauch, Christian

    2010-05-01

    Circumpolar peatlands store roughly 18 % of the globally stored carbon in soils [based on 1, 2]. Also, northern wetlands and tundra are a net source of methane (CH4), an effective greenhouse gas (GHG), with an estimated annual CH4 release of 7.2% [3] or 8.1% [4] of the global total CH4 emission. Although it is definite that Arctic tundra significantly contributes to the global methane emissions in general, regional variations in GHG fluxes are enormous. CH4 fluxes of polygonal tundra within the Siberian Lena Delta, for example, were reported to be low [5, 6], particularly at open water polygonal ponds and small lakes [7] which make up around 10 % of the delta's surface. Low methane emissions from polygonal ponds oppose that Arctic permafrost thaw ponds are generally known to emit large amounts of CH4 [8]. Combining tools of biogeochemistry and molecular microbiology, we identified sinks of CH4 in polygonal ponds from the Lena Delta that were not considered so far in GHG studies from Arctic wetlands. Pore water CH4 profiling in polygonal ponds on Samoylov, a small island in the central part of the Lena Delta, revealed a pronounced zone of CH4 oxidation near the vegetation surface in submerged layers of brown-mosses. Here, potential CH4 oxidation was an order of magnitude higher than in non-submerged mosses and in adjacent bulk soil. We could additionally show that this moss associated methane oxidation (MAMO) is hampered when exposure of light is prevented. Shading of plots with submerged Scorpidium scorpioides inhibited MAMO leading to higher CH4 concentrations and an increase in CH4 fluxes by a factor of ~13. Compared to non-submerged mosses, the submerged mosses also showed significantly lower δ13C values indicating that they use carbon dioxide derived from methane oxidation for photosynthesis. Applying stable isotope probing of DNA, type II methanotrophs were identified to be responsible for the oxidation of CH4 in the submerged Scorpidium scorpioides. Our

  15. Activity of Extracts from Submerged Cultured Mycelium of Winter Mushroom, Flammulina velutipes (Agaricomycetes), on the Immune System In Vitro.

    PubMed

    Kashina, Svetlana; Villavicencio, Lerida Liss Flores; Zaina, Silvio; Ordaz, Marco Balleza; Sabanero, Gloria Barbosa; Fujiyoshi, Victor Tsutsumi; Lopez, Myrna Sabanero

    2016-01-01

    Extracts from submerged cultured mycelium of two strains of Flammulina velutipes, a popular culinary mushroom, were obtained by ultrasound and tested in vitro to determine their activity in innate immunity (monocytes/ macrophages). In addition, polyclonal antibodies against the extracts were produced. Both extracts have similar glycoproteins that contain mannose and glucose but have different glycoproteins with galactoseamine units. Two novel immunogenic glycoproteins with molecular weights of 32 and 25 kDa have been revealed. It is thought that these proteins are produced only by submerged cultured mycelium. Both extracts show immune-enhancing activity based on the significant modification of various parameters such as cytokine production, phagocytosis, and reactive oxygen species production.

  16. Glacial to Interglacial Climate and Sea Level Changes Recorded in Submerged Speleothems, Argentarola, Italy

    NASA Astrophysics Data System (ADS)

    Folz-Donahue, K.; Dutton, A.; Antonioli, F.; Richards, D. A.; Nita, D. C.; Lambeck, K.

    2014-12-01

    Direct records of Quaternary sea level change can provide insight on the timing and nature of ice sheet retreat during glacial terminations. Such records are generally rare, particularly prior to the last deglaciation, due in part to the difficulty of recovering material from sites that have been submerged by subsequent sea-level rise. A suite of stalagmites recovered from a submerged cave on Argentarola Island in the Tyrrhenian Sea contains hiatuses that were formed when the cave became submerged by seawater. These hiatuses are remarkable due to the presence of calcite tubes secreted by serpulid worms, providing direct evidence of marine inundation. As sea level drops during the following glacial inception, the cave is drained and dense spelean calcite encases the serpulid worm tubes, forming alternating layers of spelean and serpulid calcite. U-Th dates of spelean calcite directly above and below these serpulid layers has previously been used to constrain timing and amplitude of sea level highstands in the Mediterranean. Stable isotope records from the same cave have also been used to indicate increased precipitation across the Mediterranean during Sapropel 6 (175 ka). Here we present U-Th dates and stable isotope records for three Argentarola stalagmites. These specimens were recovered from -22, -18, and -14 m relative to present sea level (rpsl), and complement previously published data for Argentarola stalagmites at -21, -18.5, and -18 m rpsl. The timing and elevation of spelean calcite directly above and below serpulid tube layers provide rare insight on rates of sea-level change between -14 and -22 m during glacial terminations and inceptions prior to the last termination. Stable isotope records from the same stalagmites are used to investigate changes in western Mediterranean climate and potential relationships to Mediterranean sapropel events.

  17. Effect of Nozzle Geometry on Characteristics of Submerged Gas Jet and Bubble Noise.

    PubMed

    Bie, Hai-Yan; Ye, Jian-Jun; Hao, Zong-Rui

    2016-10-01

    Submerged exhaust noise is one of the main noise sources of underwater vehicles. The nozzle features of pipe discharging systems have a great influence on exhaust noise, especially on the noise produced by gas-liquid two-phase flow outside the nozzle. To study the influence of nozzle geometry on underwater jet noises, a theoretical study was performed on the critical weber number at which the jet flow field morphology changes. The underwater jet noise experiments of different nozzles under various working conditions were carried out. The experimental results implied that the critical weber number at which the jet flow transformed from bubbling regime to jetting regime was basically identical with the theoretical analysis. In the condition of jetting regime, the generated cavity of elliptical and triangular nozzles was smaller than that of the circular nozzle, and the middle- and high-frequency bands increased nonlinearly. The radiated noise decreased with the decrease in nozzle diameter. Combined with theoretical analysis and experimental research, three different submerged exhaust noise reduction devices were designed, and the validation tests proved that the noise reduction device with folds and diversion cone was the most effective. © 2015 Society for Laboratory Automation and Screening.

  18. Improved production of jiangxienone in submerged fermentation of Cordyceps jiangxiensis under nitrogen deficiency.

    PubMed

    Jiang, Lu-Xi; Han, Li-Liang; Wang, Hui-Ping; Xu, Jun-Wei; Xiao, Jian-Hui

    2018-06-14

    Jiangxienone produced by Cordyceps jiangxiensis exhibits significant cytotoxicity and good selectivity against various human cancer cells, especially gastric cancer cells. In this work, the effect of nitrogen deficiency on the accumulation of jiangxienone and the transcription levels of jiangxienone biosynthesis genes was studied in submerged fermentation of C. jiangxiensis. Results showed that accumulation of jiangxienone was improved under nitrogen deficiency condition. A maximal jiangxienone content of 3.2 µg/g cell dry weight was reached at 5 mM glutamine, and it was about 8.9-fold higher than that obtained at 60 mM glutamine (control). The transcription levels of the biosynthetic pathway genes hmgr and sqs and the nitrogen regulatory gene areA were upregulated by 7-, 14-, and 28-fold, respectively, in culture with 5 mM glutamine compared to the control. It was hypothesized that the jiangxienone biosynthesis may involve the mevalonate pathway in C. jiangxiensis. Taken together, our study indicated that nitrogen deficiency is an efficient strategy for enhancing jiangxienone accumulation in submerged fermentation of C. jiangxiensis, which is useful for further understanding the regulation of jiangxienone biosynthesis.

  19. Submerged Glow-Discharge Plasma: An Economical Approach to Convert Construction Scrap Metal into Nanomaterials

    NASA Astrophysics Data System (ADS)

    Yek, Peter Nai Yuh; Rafiq Mirza Julaihi, Muhammad; Shahril Osman, Mohammad; Tiong, Tung Chuan; Lee, Wak Ha; Leing Lee, Chern

    2018-03-01

    Submerged glow-discharge plasma (SGDP) is relatively new among the various methods available for nanomaterials synthesis (NMs) techniques. This method allows great control over the production cost of nanomaterials synthesis. A lab-scale batch type SDGP technology has been constructed to produce nanomaterials and investigate the inter-relationship between plasma excitation voltages, electrodes submerged areas and electrolyte concentration. Metal oxide nanospheres has been synthesised from different electrolyte concentrations (1M-0.001M) and characterized by Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS). As the major results showed that the nanospheres are uniformly spherical with diameter size distribution are between 100 nm - 2μm. EDS analysis shown the nano-Iron Oxide have been formed. Scrap metal initially showed around 6.45% and 93.55% of Carbon and Iron composition respectively. After SGDP process to the scrap metal, Carbon content has increased to 34-35% and Iron content has reduced to around 15-40%. EDS results also shown the higher percentage of Iron amount has remained with lower electrolyte concentration and Current is proportionally related to submersion area of cathode.

  20. Numerical Wake Prediction Methods for Submerged Appended Bodies, A Literature Survey.

    DTIC Science & Technology

    1983-02-01

    Flement 62543N, Task Area 421-252, Work Unit number 1-1506-202-11. INTRODUCTION In order to design a propeller for a submerged vehicle, it is essential to...know the velocity field (i.e. wake) in the propeller plane. One of the goals of the application of computational fluid dynamics to ship design is to...tests for the purpose of obtaining wake data will be either unnecessary or would be needed only at the final stage of design . Before such a goal can

  1. Depth Estimation of Submerged Aquatic Vegetation in Clear Water Streams Using Low-Altitude Optical Remote Sensing

    PubMed Central

    Visser, Fleur; Buis, Kerst; Verschoren, Veerle; Meire, Patrick

    2015-01-01

    UAVs and other low-altitude remote sensing platforms are proving very useful tools for remote sensing of river systems. Currently consumer grade cameras are still the most commonly used sensors for this purpose. In particular, progress is being made to obtain river bathymetry from the optical image data collected with such cameras, using the strong attenuation of light in water. No studies have yet applied this method to map submergence depth of aquatic vegetation, which has rather different reflectance characteristics from river bed substrate. This study therefore looked at the possibilities to use the optical image data to map submerged aquatic vegetation (SAV) depth in shallow clear water streams. We first applied the Optimal Band Ratio Analysis method (OBRA) of Legleiter et al. (2009) to a dataset of spectral signatures from three macrophyte species in a clear water stream. The results showed that for each species the ratio of certain wavelengths were strongly associated with depth. A combined assessment of all species resulted in equally strong associations, indicating that the effect of spectral variation in vegetation is subsidiary to spectral variation due to depth changes. Strongest associations (R2-values ranging from 0.67 to 0.90 for different species) were found for combinations including one band in the near infrared (NIR) region between 825 and 925 nm and one band in the visible light region. Currently data of both high spatial and spectral resolution is not commonly available to apply the OBRA results directly to image data for SAV depth mapping. Instead a novel, low-cost data acquisition method was used to obtain six-band high spatial resolution image composites using a NIR sensitive DSLR camera. A field dataset of SAV submergence depths was used to develop regression models for the mapping of submergence depth from image pixel values. Band (combinations) providing the best performing models (R2-values up to 0.77) corresponded with the OBRA findings

  2. Laser comminution of submerged samples

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mariella, R. Jr.; Rubenchik, A.; Norton, M.

    With the long-term goal in mind of investigating possible designs for a 'universal, solid-sample comminution technique' for elemental analysis of debris and rubble, we have studied pulsed-laser ablation of solid samples that were submerged in water. Using 351-nm, 15-ns laser pulses with energy between 1 J and 0.35 J, intensities between 500 MW/cm{sup 2} and 30 MW/cm{sup 2}, and samples of broken rock [quartzite] and concrete debris, we have observed conditions in which the laser-driven process can remove material from the solid target substrate, dissolving it and/or converting it into ultrafine particles in a controlled manner. Our study used impure,more » non-metallic substrates and investigated both the rate of material removal as well as the size distribution of particles that were ablated from the process. We studied ablation at lower regimes of intensity and fluence [below 100 MW/cm{sup 2} and 0.4 J/cm{sup 2}, respectively] than has previously attracted attention and discovered that there appears to be a new regime for energy-efficient material removal [Q* < 4000 J/g, for quartzite and <2000 J/g for concrete] and for the generation of ultrafine particles.« less

  3. Shoot atmospheric contact is of little importance to aeration of deeper portions of the wetland plant Meionectes brownii; submerged organs mainly acquire O2 from the water column or produce it endogenously in underwater photosynthesis.

    PubMed

    Rich, Sarah Meghan; Pedersen, Ole; Ludwig, Martha; Colmer, Timothy David

    2013-01-01

    Partial shoot submergence is considered less stressful than complete submergence of plants, as aerial contact allows gas exchange with the atmosphere. In situ microelectrode studies of the wetland plant Meionectes brownii showed that O(2) dynamics in the submerged stems and aquatic roots of partially submerged plants were similar to those of completely submerged plants, with internal O(2) concentrations in both organs dropping to less than 5 kPa by dawn regardless of submergence level. The anatomy at the nodes and the relationship between tissue porosity and rates of O(2) diffusion through stems were studied. Stem internodes contained aerenchyma and had mean gas space area of 17.7% per cross section, whereas nodes had 8.2%, but nodal porosity was highly variable, some nodes had very low porosity or were completely occluded (ca. 23% of nodes sampled). The cumulative effect of these low porosity nodes would have impeded internal O(2) movement down stems. Therefore, regardless of the presence of an aerial connection, the deeper portions of submerged organs sourced most of their O(2) via inwards diffusion from the water column during the night, and endogenous production in underwater photosynthesis during the daytime. © 2012 Blackwell Publishing Ltd.

  4. Wall-Friction Support of Vertical Loads in Submerged Sand and Gravel Columns

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Walton, O. R.; Vollmer, H. J.; Hepa, V. S.

    Laboratory studies of the ‘floor-loads’ under submerged vertical columns of sand and/or gravel indicate that such loads can be approximated by a buoyancy-corrected Janssen-silo-theory-like relationship. Similar to conditions in storage silos filled with dry granular solids, most of the weight of the sand or gravel is supported by wall friction forces. Laboratory measurements of the loads on the floor at the base of the water-filled columns (up to 25-diameters tall) indicate that the extra floor-load from the addition of the granular solid never exceeded the load that would exist under an unsupported (wide) bed of submerged sand or gravel thatmore » has a total depth corresponding to only two column-diameters. The measured floorloads reached an asymptotic maximum value when the depth of granular material in the columns was only three or four pipe-diameters, and never increased further as the columns were filled to the top (e.g. up to heights of 10 to 25 diameters). The floor-loads were stable and remained the same for days after filling. Aggressive tapping (e.g. hitting the containing pipe on the outside, manually with a wrench up and down the height and around the circumference) could increase (and occasionally decrease) the floor load substantially, but there was no sudden collapse or slumping to a state without significant wall friction effects. Considerable effort was required, repeatedly tapping over almost the entire column wall periphery, in order to produce floor-loads that corresponded to the total buoyancy-corrected weight of granular material added to the columns. Projecting the observed laboratory behavior to field conditions would imply that a stable floor-load condition, with only a slightly higher total floor pressure than the preexisting hydrostatic-head, would exist after a water-filled bore-hole is filled with sand or gravel. Significant seismic vibration (either a large nearby event or many micro-seismic events over an extended period) would

  5. Exponential growth kinetics for Polyporus versicolor and Pleurotus ostreatus in submerged culture

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Carroad, P.A.; Wilke, C.R.

    1977-04-01

    Simple mathematical models for a batch culture of pellet-forming fungi in submerged culture were tested on growth data for Polyporus versicolor (ATCC 12679) and Pleurotus ostreatus (ATCC 9415). A kinetic model based on a growth rate proportional to the two-thirds power of the cell mass was shown to be satisfactory. A model based on a growth rate directly proportional to the cell mass fitted the data equally well, however, and may be preferable because of mathematical simplicity.

  6. Modeling tabular icebergs submerged in the ocean

    NASA Astrophysics Data System (ADS)

    Stern, A. A.; Adcroft, A.; Sergienko, O.; Marques, G.

    2017-08-01

    Large tabular icebergs calved from Antarctic ice shelves have long lifetimes (due to their large size), during which they drift across large distances, altering ambient ocean circulation, bottom-water formation, sea-ice formation, and biological primary productivity in the icebergs' vicinity. However, despite their importance, the current generation of ocean circulation models usually do not represent large tabular icebergs. In this study, we develop a novel framework to model large tabular icebergs submerged in the ocean. In this framework, tabular icebergs are represented by pressure-exerting Lagrangian elements that drift in the ocean. The elements are held together and interact with each other via bonds. A breaking of these bonds allows the model to emulate calving events (i.e., detachment of a tabular iceberg from an ice shelf) and tabular icebergs breaking up into smaller pieces. Idealized simulations of a calving tabular iceberg, its drift, and its breakup demonstrate capabilities of the developed framework.

  7. 49 CFR 192.455 - External corrosion control: Buried or submerged pipelines installed after July 31, 1971.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false External corrosion control: Buried or submerged... SAFETY STANDARDS Requirements for Corrosion Control § 192.455 External corrosion control: Buried or... against external corrosion, including the following: (1) It must have an external protective coating...

  8. 49 CFR 192.455 - External corrosion control: Buried or submerged pipelines installed after July 31, 1971.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false External corrosion control: Buried or submerged... SAFETY STANDARDS Requirements for Corrosion Control § 192.455 External corrosion control: Buried or... against external corrosion, including the following: (1) It must have an external protective coating...

  9. 49 CFR 192.455 - External corrosion control: Buried or submerged pipelines installed after July 31, 1971.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false External corrosion control: Buried or submerged... SAFETY STANDARDS Requirements for Corrosion Control § 192.455 External corrosion control: Buried or... against external corrosion, including the following: (1) It must have an external protective coating...

  10. 49 CFR 192.455 - External corrosion control: Buried or submerged pipelines installed after July 31, 1971.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false External corrosion control: Buried or submerged... SAFETY STANDARDS Requirements for Corrosion Control § 192.455 External corrosion control: Buried or... against external corrosion, including the following: (1) It must have an external protective coating...

  11. Clinical and Radiologic Outcomes of Submerged and Nonsubmerged Bone-Level Implants with Internal Hexagonal Connections in Immediate Implantation: A 5-Year Retrospective Study.

    PubMed

    Wu, Shiyu; Wu, Xiayi; Shrestha, Rachana; Lin, Jinying; Feng, Zhicai; Liu, Yudong; Shi, Yunlin; Huang, Baoxin; Li, Zhipeng; Liu, Quan; Zhang, Xiaocong; Hu, Mingxuan; Chen, Zhuofan

    2018-02-01

    To evaluate the 5-year clinical and radiologic outcome of immediate implantation using submerged and nonsubmerged techniques with bone-level implants and internal hexagonal connections and the effects of potential influencing factors. A total of 114 bone-level implants (XiVE S plus) with internal hexagonal connections inserted into 72 patients were included. Patients were followed up for 5 years. A t-test was used to statistically evaluate the marginal bone loss between the submerged and nonsubmerged groups. The cumulative survival rate (CSR) was calculated according to the life table method and illustrated with Kaplan-Meier survival curves. Comparisons of the CSR between healing protocols, guided bone regeneration, implants with different sites, lengths, and diameters were performed using log-rank tests. The 5-year cumulative implant survival rates with submerged and nonsubmerged healing were 94% and 96%, respectively. No statistically significant differences in terms of marginal bone loss, healing protocol, application of guided bone regeneration, implant site, or length were observed. High CSRs and good marginal bone levels were achieved 5 years after immediate implantation of bone-level implants with internal hexagonal connections using both the submerged and nonsubmerged techniques. Factors such as implant length, site, and application of guided bone regeneration did not have an impact on the long-term success of the implants. © 2017 by the American College of Prosthodontists.

  12. Fatigue crack growth behavior of pressure vessel steels and submerged arc weldments in a high-temperature pressurized water environment

    NASA Astrophysics Data System (ADS)

    Liaw, P. K.; Logsdon, W. A.; Begley, J. A.

    1989-10-01

    The fatigue crack growth rate (FCGR) properties of SA508 C1 2a and SA533 Gr A C1 2 pressure vessel steels and the corresponding automatic submerged are weldments were developed in a high-temperature pressurized water (HPW) environment at 288 °C (550°F) and 7.2 MPa (1044 psi) at load ratios of 0.02 and 0.50. The HPW enviromment FCGR properties of these pressure vessel steels and submerged arc weldments were generally conservative, compared with the approrpriate American Society of Mechanical Engineers (ASME) Section XI water environmental reference curve. The growth rate of fatigue cracks in the base materials, however, was considerably faster in the HPW environment than in a corresponding 288°C (550°F) base line air environment. The growth rate of fatigue cracks in the two submerged are weldments was also accelerated in the HPW environment but to a significantly lesser degree than that demonstrated by the corresponding base materials. In the air environment, fatigue striations were observed, independent of material and load ratio, while in the HPW environment, some intergranular facets were present. The greater environmental effect on crack growth rates displayed by the base materials, as compared with the weldments, was attributed to a different sulfide composition and morphology.

  13. Interrelationships of petiole air canal architecture, water depth and convective air flow in Nymphaea odorata (Nymphaeaceae)

    USDA-ARS?s Scientific Manuscript database

    Premise of the study--Nymphaea odorata grows in water up to 2 m deep, producing fewer, larger leaves in deeper water. This species has a convective flow system that moves gases from younger leaves through submerged parts to older leaves, aerating submerged parts. Petiole air canals are in the conv...

  14. Comparative study of submerged and surface culture acetification process for orange vinegar.

    PubMed

    Cejudo-Bastante, Cristina; Durán-Guerrero, Enrique; García-Barroso, Carmelo; Castro-Mejías, Remedios

    2018-02-01

    The two main acetification methodologies generally employed in the production of vinegar (surface and submerged cultures) were studied and compared for the production of orange vinegar. Polyphenols (UPLC/DAD) and volatiles compounds (SBSE-GC/MS) were considered as the main variables in the comparative study. Sensory characteristics of the obtained vinegars were also evaluated. Seventeen polyphenols and 24 volatile compounds were determined in the samples during both acetification processes. For phenolic compounds, analysis of variance showed significant higher concentrations when surface culture acetification was employed. However, for the majority of volatile compounds higher contents were observed for submerged culture acetification process, and it was also reflected in the sensory analysis, presenting higher scores for the different descriptors. Multivariate statistical analysis such as principal component analysis demonstrated the possibility of discriminating the samples regarding the type of acetification process. Polyphenols such as apigenin derivative or ferulic acid and volatile compounds such as 4-vinylguaiacol, decanoic acid, nootkatone, trans-geraniol, β-citronellol or α-terpineol, among others, were those compounds that contributed more to the discrimination of the samples. The acetification process employed in the production of orange vinegar has been demonstrated to be very significant for the final characteristics of the vinegar obtained. So it must be carefully controlled to obtain high quality products. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  15. Prosthodontic Treatment Using Vital and Non Vital Submerged Roots-Two Case Reports

    PubMed Central

    Shankar, Y. Ravi; Srinivas, K.; Surapaneni, Hemchand; Reddy, S.V. Sudhakar

    2013-01-01

    Residual ridge resorption has been considered as an inevitable consequence after extraction of the teeth. There is a gradual loss of the alveolar bone due to the pattern of bone remodeling. In spite of the availability of newer treatment modalities like endodontic restoration and periodontic procedures for preservation of the remaining teeth they are not feasible for the patients in severe stages where restoration might not be possible. The only reliable method of preserving the remaining bone is by maintaining the functional health of the teeth. Over the years, many studies showed that roots which are fractured and left behind during extractions are retained into the alveolar bone with no evidence of pathosis. Over denture as a treatment option was developed in an effort to preserve the remaining alveolar bone by retaining the natural teeth or roots. In over denture treatment, the teeth selected as abutments are prone to caries and periodontal disease over a period of time, hence evolved the vital or non vital root submergence concept. After a thorough radiographic and clinical examination, few teeth without pathosis are retained that eventually are surgically submerged in the alveolar ridge. After healing, the over denture with reaining vital or non vital teeth preserve the integrity of the bone, making the treatment an effective and successfull preventive prosthodontic treatment. PMID:24298542

  16. 49 CFR 192.457 - External corrosion control: Buried or submerged pipelines installed before August 1, 1971.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false External corrosion control: Buried or submerged... SAFETY STANDARDS Requirements for Corrosion Control § 192.457 External corrosion control: Buried or... areas in which active corrosion is found: (1) Bare or ineffectively coated transmission lines. (2) Bare...

  17. 49 CFR 192.457 - External corrosion control: Buried or submerged pipelines installed before August 1, 1971.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false External corrosion control: Buried or submerged... SAFETY STANDARDS Requirements for Corrosion Control § 192.457 External corrosion control: Buried or... areas in which active corrosion is found: (1) Bare or ineffectively coated transmission lines. (2) Bare...

  18. 49 CFR 192.457 - External corrosion control: Buried or submerged pipelines installed before August 1, 1971.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false External corrosion control: Buried or submerged... SAFETY STANDARDS Requirements for Corrosion Control § 192.457 External corrosion control: Buried or... areas in which active corrosion is found: (1) Bare or ineffectively coated transmission lines. (2) Bare...

  19. 49 CFR 192.457 - External corrosion control: Buried or submerged pipelines installed before August 1, 1971.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false External corrosion control: Buried or submerged... SAFETY STANDARDS Requirements for Corrosion Control § 192.457 External corrosion control: Buried or... areas in which active corrosion is found: (1) Bare or ineffectively coated transmission lines. (2) Bare...

  20. 49 CFR 192.457 - External corrosion control: Buried or submerged pipelines installed before August 1, 1971.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false External corrosion control: Buried or submerged... SAFETY STANDARDS Requirements for Corrosion Control § 192.457 External corrosion control: Buried or... areas in which active corrosion is found: (1) Bare or ineffectively coated transmission lines. (2) Bare...

  1. Deep challenges for China's war on water pollution.

    PubMed

    Han, Dongmei; Currell, Matthew J; Cao, Guoliang

    2016-11-01

    China's Central government has released an ambitious plan to tackle the nation's water pollution crisis. However, this is inhibited by a lack of data, particularly for groundwater. We compiled and analyzed water quality classification data from publicly available government sources, further revealing the scale and extent of the crisis. We also compiled nitrate data in shallow and deep groundwater from a range of literature sources, covering 52 of China's groundwater systems; the most comprehensive national-scale assessment yet. Nitrate pollution at levels exceeding the US EPA's maximum contaminant level (10 mg/L NO 3 N) occurs at the 90th percentile in 25 of 36 shallow aquifers and 10 out of 37 deep or karst aquifers. Isotopic compositions of groundwater nitrate (δ 15 N and δ 18 O NO3 values ranging from -14.9‰ to 35.5‰ and -8.1‰ to 51.0‰, respectively) indicate many nitrate sources including soil nitrogen, agricultural fertilizers, untreated wastewater and/or manure, and locally show evidence of de-nitrification. From these data, it is clear that contaminated groundwater is ubiquitous in deep aquifers as well as shallow groundwater (and surface water). Deep aquifers contain water recharged tens of thousands of years before present, long before widespread anthropogenic nitrate contamination. This groundwater has therefore likely been contaminated due to rapid bypass flow along wells or other conduits. Addressing the issue of well condition is urgently needed to stop further pollution of China's deep aquifers, which are some of China's most important drinking water sources. China's new 10-point Water Pollution Plan addresses previous shortcomings, however, control and remediation of deep groundwater pollution will take decades of sustained effort. Copyright © 2016. Published by Elsevier Ltd.

  2. A Modal Analysis of Submerged Composite Plates Using Digital Speckle Pattern Interferometry

    DTIC Science & Technology

    1991-05-01

    the drive point. The underwater mode shapes were slightly deformed compared to the in- air modes which is probably due to modal coupling by the dense...modes according to Leissa. The mode shapes in water are very similar to those in air with a small amount of distortion due to modal coupling by the fluid...and cantilever boundarv conditions is described in this thesis. The vibrations of the plates are studies in air and when Submerged in a water tank to

  3. Microbial production of four biodegradable siderophores under submerged fermentation.

    PubMed

    Fazary, Ahmed E; Al-Shihri, Ayed S; Alfaifi, Mohammad Y; Saleh, Kamel A; Alshehri, Mohammed A; Elbehairi, Serag Eldin I; Ju, Yi-Hsu

    2016-07-01

    Four siderophore analogues were isolated and purified from Escherichia coli, Bacillus spp. ST13, and Streptomyces pilosus microorganisms under some specific submerged fermentation conditions. In order to evaluate the highest production of this siderophore analogues through the growth, a rapid spectrophotometric screening semi-quantitative method was used, in which interestingly the analogues were isolated in its own form not its iron chelate. After chromatographic separation, the chemical structures of the isolated and purified siderophores were illustrated using detailed spectroscopic techniques. The biodegradation studies were done on that four novel isolated and purified siderophores following OECD protocols. In addition, the bioactivities of these siderophores and their iron complexes were examined and evaluated. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Instrumentation, control, and automation for submerged anaerobic membrane bioreactors.

    PubMed

    Robles, Ángel; Durán, Freddy; Ruano, María Victoria; Ribes, Josep; Rosado, Alfredo; Seco, Aurora; Ferrer, José

    2015-01-01

    A submerged anaerobic membrane bioreactor (AnMBR) demonstration plant with two commercial hollow-fibre ultrafiltration systems (PURON®, Koch Membrane Systems, PUR-PSH31) was designed and operated for urban wastewater treatment. An instrumentation, control, and automation (ICA) system was designed and implemented for proper process performance. Several single-input-single-output (SISO) feedback control loops based on conventional on-off and PID algorithms were implemented to control the following operating variables: flow-rates (influent, permeate, sludge recycling and wasting, and recycled biogas through both reactor and membrane tanks), sludge wasting volume, temperature, transmembrane pressure, and gas sparging. The proposed ICA for AnMBRs for urban wastewater treatment enables the optimization of this new technology to be achieved with a high level of process robustness towards disturbances.

  5. Study the Effect of SiO2 Based Flux on Dilution in Submerged Arc Welding

    NASA Astrophysics Data System (ADS)

    kumar, Aditya; Maheshwari, Sachin

    2017-08-01

    This paper highlights the method for prediction of dilution in submerged arc welding (SAW). The most important factors of weld bead geometry are governed by the weld dilution which controls the chemical and mechanical properties. Submerged arc welding process is used generally due to its very easy control of process variables, good penetration, high weld quality, and smooth finish. Machining parameters, with suitable weld quality can be achieved with the different composition of the flux in the weld. In the present study Si02-Al2O3-CaO flux system was used. In SiO2 based flux NiO, MnO, MgO were mixed in various proportions. The paper investigates the relationship between the process parameters like voltage, % of flux constituents and dilution with the help of Taguchi’s method. The experiments were designed according to Taguchi L9 orthogonal array, while varying the voltage at two different levels in addition to alloying elements. Then the optimal results conditions were verified by confirmatory experiments.

  6. Strain typing of acetic acid bacteria responsible for vinegar production by the submerged elaboration method.

    PubMed

    Fernández-Pérez, Rocío; Torres, Carmen; Sanz, Susana; Ruiz-Larrea, Fernanda

    2010-12-01

    Strain typing of 103 acetic acid bacteria isolates from vinegars elaborated by the submerged method from ciders, wines and spirit ethanol, was carried on in this study. Two different molecular methods were utilised: pulsed field gel electrophoresis (PFGE) of total DNA digests with a number of restriction enzymes, and enterobacterial repetitive intergenic consensus (ERIC) - PCR analysis. The comparative study of both methods showed that restriction fragment PFGE of SpeI digests of total DNA was a suitable method for strain typing and for determining which strains were present in vinegar fermentations. Results showed that strains of the species Gluconacetobacter europaeus were the most frequent leader strains of fermentations by the submerged method in the studied vinegars, and among them strain R1 was the predominant one. Results showed as well that mixed populations (at least two different strains) occurred in vinegars from cider and wine, whereas unique strains were found in spirit vinegars, which offered the most stressing conditions for bacterial growth. Copyright © 2010 Elsevier Ltd. All rights reserved.

  7. PECONIC ESTUARY: AN INVENTORY OF SUBMERGED AQUATIC VEGETATION AND HARDENED SHORELINES FOR THE PECONIC ESTUARY, NEW YORK

    EPA Science Inventory

    Executive Summary The Peconic Estuary Program (PEP) is interested in the extent of eelgrass and other submerged aquatic vegetation and in documenting changes in the shorelines of the Peconic Estuary. The Suffolk County Department of Health Services' Office of Ecology provided fun...

  8. Physical modeling of long-wave run-up mitigation using submerged breakwaters

    NASA Astrophysics Data System (ADS)

    Lee, Yu-Ting; Wu, Yun-Ta; Hwung, Hwung-Hweng; Yang, Ray-Yeng

    2016-04-01

    Natural hazard due to tsunami inundation inland has been viewed as a crucial issue for coastal engineering community. The 2004 India Ocean tsunami and the 2011 Tohoku earthquake tsunami were caused by mega scale earthquakes that brought tremendous catastrophe in the disaster regions. It is thus of great importance to develop innovative approach to achieve the reduction and mitigation of tsunami hazards. In this study, new experiments have been carried out in a laboratory-scale to investigate the physical process of long-wave through submerged breakwaters built upon a mild slope. Solitary-wave is employed to represent the characteristic of long-wave with infinite wavelength and wave period. Our goal is twofold. First of all, through changing the positions of single breakwater and multiple breakwaters upon a mild slope, the optimal locations of breakwaters can be pointed out by means of maximum run-up reduction. Secondly, through using a state-of-the-art measuring technique Bubble Image Velocimetry, which features non-intrusive and image-based measurement, the wave kinematics in the highly aerated region due to solitary-wave shoaling, breaking and uprush can be quantitated. Therefore, the mitigation of long-wave due to the construction of submerged breakwaters built upon a mild slope can be evaluated not only for imaging run-up and run-down characteristics but also for measuring turbulent velocity fields due to breaking wave. Although we understand the most devastating tsunami hazards cannot be fully mitigated with impossibility, this study is to provide quantitated information on what kind of artificial coastal structure that can withstand which level of wave loads.

  9. An atomic force microscopy study on fouling characteristics of modified PES membrane in submerged membrane bioreactor for domestic wastewater treatment

    NASA Astrophysics Data System (ADS)

    Liu, Shuo; Han, Hongjun; Liu, Yanping; Wang, Baozhen

    2008-10-01

    To investigate the fouling characteristics of modified PES membrane in submerged Membrane Bioreactor (MBR) for domestic wastewater treatment, Atomic Force Microscope (AFM) study was conducted to analyze the microstructure characteristics of PES membrane. Surface roughness and section analysis of both virgin and fouled membrane were achieved by software of NanoScope 6.12. Compared to the virgin membrane, the average roughness (Ra), square average roughness (Rms) and ten points average roughness (Rz) of fouled membrane were increased by 100.6nm, 133.7nm and 330.7nm respectively. The section analysis results indicated that the cake layer formed and membrane pore blocked were the main causes for the increase of TMP. Micro-filtration resistance analysis was conducted to support the results of AFM analysis. It is showed that membrane resistance, cake resistance, pore blocking and irreversible fouling resistance is 0.755, 1.721 and 1.386 respectively, which contributed 20%, 44%, and 36%, respectively, to total resistance of submerged MBR (at MLSS 6000mg/L and flux 21.9L/m2Â.h). The results proved that AFM could be used to properly describe the fouling characteristics of modified PES membrane in submerged MBR through roughness and section analysis.

  10. Saltwater Intrusion Through Submerged Caves due to the Venturi Effect

    NASA Astrophysics Data System (ADS)

    Khazmutdinova, K.; Nof, D.

    2016-12-01

    Saltwater intrusion into freshwater sources is a concern in coastal areas. In order to reduce the intrusion of seawater the physical mechanisms that allow this to occur must be understood. This study presents an approach to quantify saltwater intrusion in karstic coastal aquifers due to the presence of submerged caves. Many water-filled caves have variable tunnel cross-sections and often have narrow connections between two otherwise large tunnels. Generally, the diameter of these restrictions is 1 - 2 m and the flow speed within them is approximately 1 - 5 m/s. Main cave tunnels can be 10 - 20 times bigger than restrictions, and have flow speeds ranging anywhere between 0.5 cm/s and 20 cm/s. According to Bernoulli's theorem, in order to balance high velocities within a restriction, the pressure has to drop as the water flow passes through a narrow tunnel. This is expected to influence the height to which a deeper saline aquifer can penetrate in conduits connecting the narrow restriction and saltwater. For sufficiently small restrictions, saline water can invade the freshwater tunnel. The intrusion of saltwater from a deeper, saline aquifer into a fresh groundwater system due to the Venturi effect in submerged caves was computed, and an analytical and a qualitative model that captures saltwater intrusion into a fresh aquifer was developed. Using Bernoulli's theorem, we show that depths from which the saline water can be drawn into the freshwater tunnel reach up to 450 m depending on the difference in the density between fresh and saltwater. The velocity of the saline upward flow is estimated to be 1.4 m/s using the parameters for Wakulla Spring, a first order magnitude spring in Florida, with a saltwater interface 180 m below the spring cave system.

  11. Conservation of peat soils in agricultural use by infiltration of ditch water via submerged drains: results of a case study in the western peat soil area of The Netherlands

    NASA Astrophysics Data System (ADS)

    van den Akker, Jan J. H.; Hendriks, Rob F. A.

    2017-04-01

    About 8% of all soils in The Netherlands are peat soils which almost all drained with ditches and mainly in agricultural use as permanent pasture for dairy farming. The largest part of the peat meadow area is situated in the densely populated western provinces South- and North-Holland and Utrecht and is called the Green Heart and is valued as a historic open landscape. Conservation of these peats soil by raising water levels and converting the peat meadow areas mainly in very extensive grasslands or wet nature proved to be a very costly and slow process due to the strong opposition of farmers and many others who value the open cultural historic landscape and meadow birds. The use of submerged drains seems to be a promising solution acceptable for dairy farmers and effective in diminishing peat oxidation and so the associated subsidence and CO2 emissions. Oxidation of peat soils strongly depends on the depth of groundwater levels in dry periods. In dry periods the groundwater level can be 30 to 50 cm lower than the ditchwater level, which is 30 - 60 cm below soil surface. Infiltration of ditchwater via submerged drain can raise the groundwater level up to the ditchwater level and diminish the oxidation and associated subsidence and CO2 emissions with at least 50%. Since 2003 several pilots with submerged drains are started to check this theoretical reduction and to answer questions raised about water usage and water quality and grass yields and trafficability etcetera. In our presentation we focus on the results of a pilot in South-Holland concerning the hydrological aspects, however, include results from the other pilots to consider the long term aspects such as the reduction of subsidence. The use of submerged drains proves to be promising to reduce peat oxidation and so subsidence and CO2 emissions with at least 50%. Grass yields are more or less equal in parcels with versus parcels without submerged drains. Trafficability in wet periods is better and trampling

  12. DeepMeSH: deep semantic representation for improving large-scale MeSH indexing

    PubMed Central

    Peng, Shengwen; You, Ronghui; Wang, Hongning; Zhai, Chengxiang; Mamitsuka, Hiroshi; Zhu, Shanfeng

    2016-01-01

    Motivation: Medical Subject Headings (MeSH) indexing, which is to assign a set of MeSH main headings to citations, is crucial for many important tasks in biomedical text mining and information retrieval. Large-scale MeSH indexing has two challenging aspects: the citation side and MeSH side. For the citation side, all existing methods, including Medical Text Indexer (MTI) by National Library of Medicine and the state-of-the-art method, MeSHLabeler, deal with text by bag-of-words, which cannot capture semantic and context-dependent information well. Methods: We propose DeepMeSH that incorporates deep semantic information for large-scale MeSH indexing. It addresses the two challenges in both citation and MeSH sides. The citation side challenge is solved by a new deep semantic representation, D2V-TFIDF, which concatenates both sparse and dense semantic representations. The MeSH side challenge is solved by using the ‘learning to rank’ framework of MeSHLabeler, which integrates various types of evidence generated from the new semantic representation. Results: DeepMeSH achieved a Micro F-measure of 0.6323, 2% higher than 0.6218 of MeSHLabeler and 12% higher than 0.5637 of MTI, for BioASQ3 challenge data with 6000 citations. Availability and Implementation: The software is available upon request. Contact: zhusf@fudan.edu.cn Supplementary information: Supplementary data are available at Bioinformatics online. PMID:27307646

  13. DeepMeSH: deep semantic representation for improving large-scale MeSH indexing.

    PubMed

    Peng, Shengwen; You, Ronghui; Wang, Hongning; Zhai, Chengxiang; Mamitsuka, Hiroshi; Zhu, Shanfeng

    2016-06-15

    Medical Subject Headings (MeSH) indexing, which is to assign a set of MeSH main headings to citations, is crucial for many important tasks in biomedical text mining and information retrieval. Large-scale MeSH indexing has two challenging aspects: the citation side and MeSH side. For the citation side, all existing methods, including Medical Text Indexer (MTI) by National Library of Medicine and the state-of-the-art method, MeSHLabeler, deal with text by bag-of-words, which cannot capture semantic and context-dependent information well. We propose DeepMeSH that incorporates deep semantic information for large-scale MeSH indexing. It addresses the two challenges in both citation and MeSH sides. The citation side challenge is solved by a new deep semantic representation, D2V-TFIDF, which concatenates both sparse and dense semantic representations. The MeSH side challenge is solved by using the 'learning to rank' framework of MeSHLabeler, which integrates various types of evidence generated from the new semantic representation. DeepMeSH achieved a Micro F-measure of 0.6323, 2% higher than 0.6218 of MeSHLabeler and 12% higher than 0.5637 of MTI, for BioASQ3 challenge data with 6000 citations. The software is available upon request. zhusf@fudan.edu.cn Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press.

  14. Comparison of fouling characteristics in different pore-sized submerged ceramic membrane bioreactors.

    PubMed

    Jin, Le; Ong, Say Leong; Ng, How Yong

    2010-12-01

    Membrane fouling, the key disadvantage that inevitably occurs continuously in the membrane bioreactor (MBR), baffles the wide-scale application of MBR. Ceramic membrane, which possesses high chemical and thermal resistance, has seldom been used in MBR to treat municipal wastewater. Four ceramic membranes with the same materials but different pore sizes, ranging from 80 to 300 nm, were studied in parallel using four lab-scale submerged MBRs (i.e., one type of ceramic membrane in one MBR). Total COD and ammonia nitrogen removal efficiencies were observed to be consistently above 94.5 and 98%, respectively, in all submerged ceramic membrane bioreactors. The experimental results showed that fouling was mainly affected by membrane's microstructure, surface roughness and pore sizes. Ceramic membrane with the roughest surface and biggest pore size (300 nm) had the highest fouling potential with respect to the TMP profile. The 80 nm membrane with a smoother surface and relatively uniform smaller pore openings experienced least membrane fouling with respect to TMP increase. The effects of the molecular weight distribution, particle size distribution and other biomass characteristics such as extracellular polymeric substances, zeta potential and capillary suction time, were also investigated in this study. Results showed that no significant differences of these attributes were observed. These observations indicate that the membrane surface properties are the dominant factors leading to different fouling potential in this study. Copyright © 2010 Elsevier Ltd. All rights reserved.

  15. Unusual energy properties of leaky backward Lamb waves in a submerged plate.

    PubMed

    Nedospasov, I A; Mozhaev, V G; Kuznetsova, I E

    2017-05-01

    It is found that leaky backward Lamb waves, i.e. waves with negative energy-flux velocity, propagating in a plate submerged in a liquid possess extraordinary energy properties distinguishing them from any other type of waves in isotropic media. Namely, the total time-averaged energy flux along the waveguide axis is equal to zero for these waves due to opposite directions of the longitudinal energy fluxes in the adjacent media. This property gives rise to the fundamental question of how to define and calculate correctly the energy velocity in such an unusual case. The procedure of calculation based on incomplete integration of the energy flux density over the plate thickness alone is applied. The derivative of the angular frequency with respect to the wave vector, usually referred to as the group velocity, happens to be close to the energy velocity defined by this mean in that part of the frequency range where the backward mode exists in the free plate. The existence region of the backward mode is formally increased for the submerged plate in comparison to the free plate as a result of the liquid-induced hybridization of propagating and nonpropagating (evanescent) Lamb modes. It is shown that the Rayleigh's principle (i.e. equipartition of total time-averaged kinetic and potential energies for time-harmonic acoustic fields) is violated due to the leakage of Lamb waves, in spite of considering nondissipative media. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Field Test to Evaluate Deep Borehole Disposal.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hardin, Ernest; Brady, Patrick Vane.; Clark, Andrew Jordan

    The U.S. Department of Energy (DOE) has embarked on the Deep Borehole Field Test (DBFT), which will investigate whether conditions suitable for disposal of radioactive waste can be found at a depth of up to 5 km in the earth’s crust. As planned, the DBFT will demonstrate drilling and construction of two boreholes, one for initial scientific characterization, and the other at a larger diameter such as could be appropriate for waste disposal (the DBFT will not involve radioactive waste). A wide range of geoscience activities is planned for the Characterization Borehole, and an engineering demonstration of test package emplacementmore » and retrieval is planned for the larger Field Test Borehole. Characterization activities will focus on measurements and samples that are important for evaluating the long-term isolation capability of the Deep Borehole Disposal (DBD) concept. Engineering demonstration activities will focus on providing data to evaluate the concept’s operational safety and practicality. Procurement of a scientifically acceptable DBFT site and a site management contractor is now underway. The concept of deep borehole disposal (DBD) for radioactive wastes is not new. It was considered by the National Academy of Science (NAS 1957) for liquid waste, studied in the 1980’s in the U.S. (Woodward–Clyde 1983), and has been evaluated by European waste disposal R&D programs in the past few decades (for example, Grundfelt and Crawford 2014; Grundfelt 2010). Deep injection of wastewater including hazardous wastes is ongoing in the U.S. and regulated by the Environmental Protection Agency (EPA 2001). The DBFT is being conducted with a view to use the DBD concept for future disposal of smaller-quantity, DOE-managed wastes from nuclear weapons production (i.e., Cs/Sr capsules and granular solid wastes). However, the concept may also have broader applicability for nations that have a need to dispose of limited amounts of spent fuel from nuclear power reactors

  17. Chronobiology of deep-water decapod crustaceans on continental margins.

    PubMed

    Aguzzi, Jacopo; Company, Joan B

    2010-01-01

    Species have evolved biological rhythms in behaviour and physiology with a 24-h periodicity in order to increase their fitness, anticipating the onset of unfavourable habitat conditions. In marine organisms inhabiting deep-water continental margins (i.e. the submerged outer edges of continents), day-night activity rhythms are often referred to in three ways: vertical water column migrations (i.e. pelagic), horizontal displacements within benthic boundary layer of the continental margin, along bathymetric gradients (i.e. nektobenthic), and endobenthic movements (i.e. rhythmic emergence from the substrate). Many studies have been conducted on crustacean decapods that migrate vertically in the water column, but much less information is available for other endobenthic and nektobenthic species. Also, the types of displacement and major life habits of most marine species are still largely unknown, especially in deep-water continental margins, where steep clines in habitat factors (i.e. light intensity and its spectral quality, sediment characteristics, and hydrography) take place. This is the result of technical difficulties in performing temporally scheduled sampling and laboratory testing on living specimens. According to this scenario, there are several major issues that still need extensive research in deep-water crustacean decapods. First, the regulation of their behaviour and physiology by a biological clock is almost unknown compared to data for coastal species that are easily accessible to direct observation and sampling. Second, biological rhythms may change at different life stages (i.e. size-related variations) or at different moments of the reproductive cycle (e.g. at egg-bearing) based on different intra- and interspecific interactions. Third, there is still a major lack of knowledge on the links that exist among the observed bathymetric distributions of species and selected autoecological traits that are controlled by their biological clock, such as the

  18. Submerged Gas Jet Penetration: A Study of Bubbling Versus Jetting and Side Versus Bottom Blowing in Copper Bath Smelting

    NASA Astrophysics Data System (ADS)

    Kapusta, Joël P. T.

    2017-06-01

    Although the bottom blowing ShuiKouShan process has now been widely implemented in China, in both lead and copper smelters, some doubts, questions, and concerns still seem to prevail in the metallurgical community outside China. In the author's opinion, part of these doubts and concerns could be addressed by a better general understanding of key concepts of submerged gas injection, including gas jet trajectory and penetration, and the concept, application, and benefits of sonic injection in jetting regime. To provide some answers, this article first offers a discussion on the historical developments of the theory and mathematical characterization of submerged gas jet trajectory, including the proposed criteria for the transition from bubbling to jetting regime and the application of the Prandtl-Meyer theory to submerged gas jets. A second part is devoted to a quantitative study of submerged gas jet penetration in copper bath smelting, including a comparison between bubbling and jetting regimes, and side versus bottom blowing. In the specific cases studied, the calculated gas jet axis trajectory length in jetting regime is 159 cm for bottom blowing, whereas it varies between 129 and 168 cm for side blowing for inclination angles of +18° to -30° to the horizontal. This means that side blowing in the jetting regime would provide a deeper penetration and longer gas jet trajectory than generally obtained by conventional bath smelting vessels such as the Noranda and Teniente reactors. The theoretical results of this study do corroborate the successful high-intensity practice of the slag make converting process at Glencore Nickel in Canada that operates under high oxygen shrouded injection in the jetting regime, and this would then suggest that retrofitting conventional low-pressure, side-blowing tuyeres of bath smelting and converting reactors with sonic injectors in jetting regime certainly appears as a valuable option for process intensification with higher oxygen

  19. 76 FR 55090 - Commercial Lease of Submerged Lands for Renewable Energy Development on the Outer Continental Shelf

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-06

    ...-2011-0039] Commercial Lease of Submerged Lands for Renewable Energy Development on the Outer... renewable energy leases on the Outer Continental Shelf. In the preamble to the April 29, 2009, Final Rule, ``Renewable Energy and Alternate Uses of Existing Facilities on the Outer Continental Shelf,'' BOEMRE stated...

  20. Chemical treatment of contaminated sediment for phosphorus control and subsequent effects on ammonia-oxidizing and ammonia-denitrifying microorganisms and on submerged macrophyte revegetation.

    PubMed

    Lin, Juan; Zhong, Yufang; Fan, Hua; Song, Chaofeng; Yu, Chao; Gao, Yue; Xiong, Xiong; Wu, Chenxi; Liu, Jiantong

    2017-01-01

    In this work, sediments were treated with calcium nitrate, aluminum sulfate, ferric sulfate, and Phoslock®, respectively. The impact of treatments on internal phosphorus release, the abundance of nitrogen cycle-related functional genes, and the growth of submerged macrophytes were investigated. All treatments reduced total phosphorus (TP) and soluble reactive phosphorus (SRP) in interstitial water, and aluminum sulfate was most efficient. Aluminum sulfate also decreased TP and SRP in overlying water. Treatments significantly changed P speciations in the sediment. Phoslock® transformed other P species into calcium-bound P. Calcium nitrate, ferric sulfate, and Phoslock® had negative influence on ammonia oxidizers, while four chemicals had positive influence on denitrifies, indicating that chemical treatment could inhibit nitrification but enhance denitrification. Aluminum sulfate had decreased chlorophyll content of the leaves of submerged macrophytes, while ferric sulfate and Phoslock® treatment would inhibit the growth of the root. Based on the results that we obtained, we emphasized that before application of chemical treatment, the effects on submerged macrophyte revegetation should be taken into consideration.

  1. Biochemical Characterization of Extracellular Cellulase from Tuber maculatum Mycelium Produced Under Submerged Fermentation.

    PubMed

    Bedade, Dattatray K; Singhal, Rekha S; Turunen, Ossi; Deska, Jan; Shamekh, Salem

    2017-02-01

    Interaction of truffle mycelium with the host plant involves the excretion of extracellular enzymes. The ability of Tuber maculatum mycelium to produce an extracellular cellulase during submerged fermentation was demonstrated for the first time. T. maculatum mycelia were isolated and tested for extracellular cellulase production at variable pH on solid agar medium, and the highest activity was observed at pH 7.0. Furthermore, T. maculatum was subjected to submerged fermentation in basal salt medium for cellulase production. Under optimized conditions using sodium carboxymethyl cellulose (0.5 % w/v) as carbon source and an initial pH of 7.0, the enzyme production yielded 1.70 U/mL of cellulase in the cell-free supernatant after 7 days of incubation time. The optimum of the obtained cellulase's activity was at pH 5.0 and a temperature of 50 °C. The enzyme showed good thermostability at 50 °C by retaining 99 % of its maximal activity over an incubation time of 100 min. The cellulase activity was inhibited by Fe 2+ and slightly activated by Mn 2+ and Cu 2+ at 1 mM concentration. The results indicated that truffle mycelium is utilizing cellulosic energy source in the root system, and the optimal conditions are those existing in the acidic Finnish soil.

  2. Deepwater Program: Lophelia II, continuing ecological research on deep-sea corals and deep-reef habitats in the Gulf of Mexico

    USGS Publications Warehouse

    Demopoulos, Amanda W.J.; Ross, Steve W.; Kellogg, Christina A.; Morrison, Cheryl L.; Nizinski, Martha S.; Prouty, Nancy G.; Bourque, Jill R.; Galkiewicz, Julie P.; Gray, Michael A.; Springmann, Marcus J.; Coykendall, D. Katharine; Miller, Andrew; Rhode, Mike; Quattrini, Andrea; Ames, Cheryl L.; Brooke, Sandra D.; McClain Counts, Jennifer; Roark, E. Brendan; Buster, Noreen A.; Phillips, Ryan M.; Frometa, Janessy

    2017-12-11

    The deep sea is a rich environment composed of diverse habitat types. While deep-sea coral habitats have been discovered within each ocean basin, knowledge about the ecology of these habitats and associated inhabitants continues to grow. This report presents information and results from the Lophelia II project that examined deep-sea coral habitats in the Gulf of Mexico. The Lophelia II project focused on Lophelia pertusa habitats along the continental slope, at depths ranging from 300 to 1,000 meters. The chapters are authored by several scientists from the U.S. Geological Survey, National Oceanic and Atmospheric Administration, University of North Carolina Wilmington, and Florida State University who examined the community ecology (from microbes to fishes), deep-sea coral age, growth, and reproduction, and population connectivity of deep-sea corals and inhabitants. Data from these studies are presented in the chapters and appendixes of the report as well as in journal publications. This study was conducted by the Ecosystems Mission Area of the U.S. Geological Survey to meet information needs identified by the Bureau of Ocean Energy Management.

  3. Mosaicking Techniques for Deep Submergence Vehicle Video Imagery - Applications to Ridge2000 Science

    NASA Astrophysics Data System (ADS)

    Mayer, L.; Rzhanov, Y.; Fornari, D. J.; Soule, A.; Shank, T. M.; Beaulieu, S. E.; Schouten, H.; Tivey, M.

    2004-12-01

    Severe attenuation of visible light and limited power capabilities of many submersible vehicles require acquisition of imagery from short ranges, rarely exceeding 8-10 meters. Although modern video- and photo-equipment makes high-resolution video surveying possible, the field of view of each image remains relatively narrow. To compensate for the deficiencies in light and field of view researchers have been developing techniques allowing for combining images into larger composite images i.e., mosaicking. A properly constructed, accurate mosaic has a number of well-known advantages in comparison with the original sequence of images, the most notable being improved situational awareness. We have developed software strategies for PC-based computers that permit conversion of video imagery acquired from any underwater vehicle, operated within both absolute (e.g. LBL or USBL) or relative (e.g. Doppler Velocity Log-DVL) navigation networks, to quickly produce a set of geo-referenced photomosaics which can then be directly incorporated into a Geographic Information System (GIS) data base. The timescale of processing is rapid enough to permit analysis of the resulting mosaics between submersible dives thus enhancing the efficiency of deep-sea research. Commercial imaging processing packages usually handle cases where there is no or little parallax - an unlikely situation for undersea world where terrain has pronounced 3D content and imagery is acquired from moving platforms. The approach we have taken is optimized for situations in which there is significant relief and thus parallax in the imagery (e.g. seafloor fault scarps or constructional volcanic escarpments and flow fronts). The basis of all mosaicking techniques is a pair-wise image registration method that finds a transformation relating pixels of two consecutive image frames. We utilize a "rigid affine model" with four degrees of freedom for image registration that allows for camera translation in all directions and

  4. Interaction of wave with a body submerged below an ice sheet with multiple arbitrarily spaced cracks

    NASA Astrophysics Data System (ADS)

    Li, Z. F.; Wu, G. X.; Ji, C. Y.

    2018-05-01

    The problem of wave interaction with a body submerged below an ice sheet with multiple arbitrarily spaced cracks is considered, based on the linearized velocity potential theory together with the boundary element method. The ice sheet is modeled as a thin elastic plate with uniform properties, and zero bending moment and shear force conditions are enforced at the cracks. The Green function satisfying all the boundary conditions including those at cracks, apart from that on the body surface, is derived and is expressed in an explicit integral form. The boundary integral equation for the velocity potential is constructed with an unknown source distribution over the body surface only. The wave/crack interaction problem without the body is first solved directly without the need for source. The convergence and comparison studies are undertaken to show the accuracy and reliability of the solution procedure. Detailed numerical results through the hydrodynamic coefficients and wave exciting forces are provided for a body submerged below double cracks and an array of cracks. Some unique features are observed, and their mechanisms are analyzed.

  5. Investigation of submerged waterjet cavitation through surface property and flow information in ambient water

    NASA Astrophysics Data System (ADS)

    Kang, Can; Liu, Haixia; Zhang, Tao; Li, Qing

    2017-12-01

    To illuminate primary factors influencing the morphology of the surface impinged by submerged waterjet, experiments were performed at high jet pressures from 200 to 320 MPa. The cavitation phenomenon involved in the submerged waterjet was emphasized. Copper specimens were used as the targets enduring the impingement of high-pressure waterjets. The microhardness of the specimen was measured. Surface morphology was observed using an optical profiling microscope. Pressure fluctuations near the jet stream were acquired with miniature pressure transducers. The results show that microhardness increases with jet pressure and impingement time, and the hardening effect is restricted within a thin layer underneath the target surface. A synthetic effect is testified with the plastic deformation and cavities on the specimen surfaces. Characteristics of different cavitation erosion stages are illustrated by surface morphology. At the same jet pressure, the smallest standoff distance is not corresponding to the highest mass removal rate. Instead, there is an optimal standoff distance. With the increase of jet pressure, overall mass removal rate rises as well. Low-frequency components are predominant in the pressure spectra and the dual-peak pattern is typical. As the streamwise distance from the nozzle is enlarged, pressure amplitudes associated with cavitation bubble collapse are improved.

  6. A unified model for reverberation and submerged object scattering in a stratified ocean waveguide.

    PubMed

    Makris, N C; Ratilal, P

    2001-03-01

    A unified model for reverberation and submerged target scattering in a stratified medium is developed from wave theory. The advantage of the unified approach is that it enables quantitative predictions to be made of the target-echo-to-reverberation ratio in an ocean waveguide. Analytic expressions are derived for both deterministic and stochastic scattering from the seafloor and subseafloor. Asymptotic techniques are used to derive expressions for the scattering of broadband waveforms from distant objects or surfaces. Expressions are then obtained for the scattered field after beamforming with a horizontal line array. The model is applied to problems of active detection in shallow water. Sample calculations for narrow-band signals indicate that the detection of submerged target echoes above diffuse seafloor reverberation is highly dependent upon water column and sediment stratification as well as array aperture, source, receiver, and target locations, in addition to the scattering properties of the target and seafloor. The model is also applied to determine the conditions necessary for echo returns from discrete geomorphologic features of the seafloor and subseafloor to stand prominently above diffuse seafloor reverberation. This has great relevance to the geologic clutter problem encountered by active sonar systems operating in shallow water, as well as to the remote sensing of underwater geomorphology.

  7. Astronaut Sunita L. Williams Submerges Into Waters of the Neutral Buoyancy Laboratory (NBL)

    NASA Technical Reports Server (NTRS)

    2006-01-01

    Astronauts Sunita L. Williams, Expedition 14 flight engineer, and Robert L. Curbeam (partially obscured), STS-116 mission specialist, are about to be submerged in the waters of the Neutral Buoyancy Laboratory (NBL) near Johnson Space Center. Williams and Curbeam are attired in training versions of the Extravehicular Mobility Unit (EMU) space suit. SCUBA-equipped divers are in the water to assist the crew members in their rehearsal intended to help prepare them for work on the exterior of the International Space Station (ISS).

  8. 77 FR 5529 - Commercial Lease of Submerged Lands for Renewable Energy Development on the Outer Continental Shelf

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-03

    ... Submerged Lands for Renewable Energy Development on the Outer Continental Shelf AGENCY: Bureau of Ocean... use Form 0008 to issue commercial renewable energy leases on the Outer Continental Shelf (OCS). In the preamble to the April 29, 2009, Final Rule, ``Renewable Energy and Alternate Uses of Existing Facilities on...

  9. Determining the Discharge Rate from a Submerged Oil Leaks using ROV Video and CFD study

    NASA Astrophysics Data System (ADS)

    Saha, Pankaj; Shaffer, Frank; Shahnam, Mehrdad; Savas, Omer; Devites, Dave; Steffeck, Timothy

    2016-11-01

    The current paper reports a technique to measure the discharge rate by analyzing the video from a Remotely Operated Vehicle (ROV). The technique uses instantaneous images from ROV video to measure the velocity of visible features (turbulent eddies) along the boundary of an oil leak jet and subsequently classical theory of turbulent jets is imposed to determine the discharge rate. The Flow Rate Technical Group (FRTG) Plume Team developed this technique that manually tracked the visible features and produced the first accurate government estimates of the oil discharge rate from the Deepwater Horizon (DWH). For practical application this approach needs automated control. Experiments were conducted at UC Berkeley and OHMSETT that recorded high speed, high resolution video of submerged dye-colored water or oil jets and subsequently, measured the velocity data employing LDA and PIV software. Numerical simulation have been carried out using experimental submerged turbulent oil jets flow conditions employing LES turbulence closure and VOF interface capturing technique in OpenFOAM solver. The CFD results captured jet spreading angle and jet structures in close agreement with the experimental observations. The work was funded by NETL and DOI Bureau of Safety and Environmental Enforcement (BSEE).

  10. Oxygen, pH, and Eh microprofiles around submerged macrophyte Vallisneria natans response to growing stages

    NASA Astrophysics Data System (ADS)

    Dong, B.; Wang, G. X.; Yu, H. G.

    2017-08-01

    The periphyton, attached to the surfaces of submerged plants, has important effects on plant growth and development in eutrophic waters. Periphyton complicates the microenvironment of diffusive boundary layer around submerged plants. We researched periphyton characteristics, oxygen (O2), pH, and Eh microprofiles at various growing stages of Vallisneria natans. The results suggested that during the growing period of V. natans, O2 concentration and pH decreased from 0 to 2 mm above the leaf surface, whereas the Eh increased. As V. natans grew, O2 and pH gradually increased until they peaked during stable growing stages, while the Eh decreased. However, during the decline stage, O2 and pH gradually decreased, and Eh increased. To summarise, O2 and pH showed a unimodal pattern in response to the life cycle of V. natans, with the maximum levels during the stable growth stage and the minimum levels during the rapid growth and decline stages. Our study demonstrated that V. natans growth induced steep gradients in O2 concentrations, pH, and Eh at the DBL by increasing the layer’s thickness, macrophyte photosynthetic capacity, and periphyton biomass in eutrophic waters.

  11. Response of sago pondweed, a submerged aquatic macrophyte, to herbicides in three laboratory culture systems

    USGS Publications Warehouse

    Fleming, W.J.; Ailstock, M.S.; Momot, J.J.; Norman, C.M.; Gorsuch, Joseph W.; Lower, William R.; Wang, Wun-cheng; Lewis, M.A.

    1991-01-01

    The phytotoxicity of atrazine, paraquat, glyphosate, and alachlor to sago pondweed (Potamogeton pectinatus), a submerged aquatic macrophyte, was tested under three types of laboratory culture conditions. In each case, tests were conducted in static systems, the test period was four weeks, and herbicide exposure was chronic, resulting from a single addition of herbicide to the test vessels at the beginning of the test period. The three sets of test conditions employed were(1) axenic cultures in 125-mL flasks containing a nutrient media and sucrose; (2) a microcosm system employing 18.9-L buckets containing a sand, shell, and peat substrate; and (3) an algae-free system employing O.95-L jars containing reconstituted freshwater and a nutrient agar substrate. The primary variable measured was biomass production. Plants grew well in all three test systems, with biomass of untreated plants increasing by a factor of about 5 to 6.5 during the four-week test period. Biomass production in response to herbicide exposure differed significantly among culture systems, which demonstrates the need for a standardized testing protocol for evaluating the effects of toxics on submerged aquatic plants.

  12. EAARL coastal topography-western Florida, post-Hurricane Charley, 2004: seamless (bare earth and submerged.

    USGS Publications Warehouse

    Nayegandhi, Amar; Bonisteel, Jamie M.; Wright, C. Wayne; Sallenger, A.H.; Brock, John C.; Yates, Xan

    2010-01-01

    Project Description These remotely sensed, geographically referenced elevation measurements of lidar-derived seamless (bare-earth and submerged) topography were produced as a collaborative effort between the U.S. Geological Survey (USGS), Coastal and Marine Geology Program (CMGP), St. Petersburg, FL, and the National Aeronautics and Space Administration (NASA), Wallops Flight Facility, VA. This project provides highly detailed and accurate datasets of a portion of the western Florida coastline beachface, acquired post-Hurricane Charley on August 17 and 18, 2004. The datasets are made available for use as a management tool to research scientists and natural-resource managers. An innovative airborne lidar instrument originally developed at the NASA Wallops Flight Facility, and known as the Experimental Advanced Airborne Research Lidar (EAARL), was used during data acquisition. The EAARL system is a raster-scanning, waveform-resolving, green-wavelength (532-nanometer) lidar designed to map near-shore bathymetry, topography, and vegetation structure simultaneously. The EAARL sensor suite includes the raster-scanning, water-penetrating full-waveform adaptive lidar, a down-looking red-green-blue (RGB) digital camera, a high-resolution multispectral color infrared (CIR) camera, two precision dual-frequency kinematic carrier-phase GPS receivers, and an integrated miniature digital inertial measurement unit, which provide for sub-meter georeferencing of each laser sample. The nominal EAARL platform is a twin-engine Cessna 310 aircraft, but the instrument may be deployed on a range of light aircraft. A single pilot, a lidar operator, and a data analyst constitute the crew for most survey operations. This sensor has the potential to make significant contributions in measuring sub-aerial and submarine coastal topography within cross-environmental surveys. Elevation measurements were collected over the survey area using the EAARL system, and the resulting data were then

  13. Towards deep inclusion for equity-oriented health research priority-setting: A working model.

    PubMed

    Pratt, Bridget; Merritt, Maria; Hyder, Adnan A

    2016-02-01

    Growing consensus that health research funders should align their investments with national research priorities presupposes that such national priorities exist and are just. Arguably, justice requires national health research priority-setting to promote health equity. Such a position is consistent with recommendations made by the World Health Organization and at global ministerial summits that health research should serve to reduce health inequalities between and within countries. Thus far, no specific requirements for equity-oriented research priority-setting have been described to guide policymakers. As a step towards the explication and defence of such requirements, we propose that deep inclusion is a key procedural component of equity-oriented research priority-setting. We offer a model of deep inclusion that was developed by applying concepts from work on deliberative democracy and development ethics. This model consists of three dimensions--breadth, qualitative equality, and high-quality non-elite participation. Deep inclusion is captured not only by who is invited to join a decision-making process but also by how they are involved and by when non-elite stakeholders are involved. To clarify and illustrate the proposed dimensions, we use the sustained example of health systems research. We conclude by reviewing practical challenges to achieving deep inclusion. Despite the existence of barriers to implementation, our model can help policymakers and other stakeholders design more inclusive national health research priority-setting processes and assess these processes' depth of inclusion. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Characteristics and limitations of GPS L1 observations from submerged antennas - Theoretical investigation in snow, ice, and freshwater and practical observations within a freshwater layer

    NASA Astrophysics Data System (ADS)

    Steiner, Ladina; Meindl, Michael; Geiger, Alain

    2018-05-01

    Observations from a submerged GNSS antenna underneath a snowpack need to be analyzed to investigate its potential for snowpack characterization. The magnitude of the main interaction processes involved in the GPS L1 signal propagation through different layers of snow, ice, or freshwater is examined theoretically in the present paper. For this purpose, the GPS signal penetration depth, attenuation, reflection, refraction as well as the excess path length are theoretically investigated. Liquid water exerts the largest influence on GPS signal propagation through a snowpack. An experiment is thus set up with a submerged geodetic GPS antenna to investigate the influence of liquid water on the GPS observations. The experimental results correspond well with theory and show that the GPS signal penetrates the liquid water up to three centimeters. The error in the height component due to the signal propagation delay in water can be corrected with a newly derived model. The water level above the submerged antenna could also be estimated.

  15. 75 FR 7435 - Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-19

    .... 100105009-0053-01] RIN 0648-AY51 Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic Deep-Sea Red Crab Specifications AGENCY: National Marine Fisheries Service (NMFS... comments. SUMMARY: NMFS proposes 2010 specifications for the Atlantic deep-sea red crab fishery, including...

  16. 75 FR 27219 - Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-14

    .... 100105009-0167-02] RIN 0648-AY51 Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic Deep-Sea Red Crab Specifications AGENCY: National Marine Fisheries Service (NMFS... final specifications for the 2010 Atlantic deep- sea red crab fishery, including a target total...

  17. Ram-recovery Characteristics of NACA Submerged Inlets at High Subsonic Speeds

    NASA Technical Reports Server (NTRS)

    Hall, Charles F; Frank, Joseph L

    1948-01-01

    Results are presented of an experimental investigation of the characteristics of NACA submerged inlets on a model of a fighter airplane for Mach numbers from 0.30 to 0.875. The effects on the ram-recovery ratio at the inlets of Mach number, angle of attack, boundary-layer thickness on the fuselage, inlet location, and boundary-layer deflectors are shown. The data indicate only a slight decrease in ram-recovery ratio for the inlets ahead of or just behind the wing leading edge as Mach number increased, but showed large decreases at high Mach numbers for the inlets aft of the point of maximum thickness of the wing.

  18. Cell growth and catecholase production for Polyporus versicolor in submerged culture

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Carroad, P.A.; Wilke, C.R.

    1977-04-01

    Cell growth and catecholase production for Polyporus versicolor (ATCC 12679) were studied in mechanically agitated submerged culture, as functions of temperature. The exponential-phase growth rate exhibited a maximum at 28/sup 0/C. Over the range of 20/sup 0/C to approximately 30/sup 0/C, both cell mass and enzyme yield factors were constant. At higher temperatures (30 to 40/sup 0/C) cell mass yield factor decreased and enzyme yield factor increased. Specific respiration rate of P. versicolor was determined. Thermal deactivation of catecholase was investigated between 30 and 50/sup 0/C, and deactivation rates were fit to an Arrhenius rate expression.

  19. 75 FR 49420 - Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-13

    .... 100513223-0289-02] RIN 0648-AY88 Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic Deep-Sea Red Crab Specifications In- season Adjustment AGENCY: National Marine...-sea (DAS) allocation for the Atlantic deep- sea red crab fishery that were implemented in May 2010...

  20. Accurate Determination of the Frequency Response Function of Submerged and Confined Structures by Using PZT-Patches†.

    PubMed

    Presas, Alexandre; Valentin, David; Egusquiza, Eduard; Valero, Carme; Egusquiza, Mònica; Bossio, Matias

    2017-03-22

    To accurately determine the dynamic response of a structure is of relevant interest in many engineering applications. Particularly, it is of paramount importance to determine the Frequency Response Function (FRF) for structures subjected to dynamic loads in order to avoid resonance and fatigue problems that can drastically reduce their useful life. One challenging case is the experimental determination of the FRF of submerged and confined structures, such as hydraulic turbines, which are greatly affected by dynamic problems as reported in many cases in the past. The utilization of classical and calibrated exciters such as instrumented hammers or shakers to determine the FRF in such structures can be very complex due to the confinement of the structure and because their use can disturb the boundary conditions affecting the experimental results. For such cases, Piezoelectric Patches (PZTs), which are very light, thin and small, could be a very good option. Nevertheless, the main drawback of these exciters is that the calibration as dynamic force transducers (relationship voltage/force) has not been successfully obtained in the past. Therefore, in this paper, a method to accurately determine the FRF of submerged and confined structures by using PZTs is developed and validated. The method consists of experimentally determining some characteristic parameters that define the FRF, with an uncalibrated PZT exciting the structure. These parameters, which have been experimentally determined, are then introduced in a validated numerical model of the tested structure. In this way, the FRF of the structure can be estimated with good accuracy. With respect to previous studies, where only the natural frequencies and mode shapes were considered, this paper discuss and experimentally proves the best excitation characteristic to obtain also the damping ratios and proposes a procedure to fully determine the FRF. The method proposed here has been validated for the structure vibrating

  1. Bed Surface Adjustments to Spatially Variable Flow in Low Relative Submergence Regimes

    NASA Astrophysics Data System (ADS)

    Monsalve, A.; Yager, E. M.

    2017-11-01

    In mountainous rivers, large relatively immobile grains partly control the local and reach-averaged flow hydraulics and sediment fluxes. When the flow depth is similar to the size of these grains (low relative submergence), heterogeneous flow structures and plunging flow cause spatial distributions of bed surface elevations, textures, and sedimentation rates. To explore how the bed surface responds to these flow variations we conducted a set of experiments in which we varied the relative submergence of staggered hemispheres (simulated large boulders) between runs. All experiments had the same average sediment transport capacity, upstream sediment supply, and initial bed thickness and grain size distribution. We combined our laboratory measurements with a 3-D flow model to obtain the detailed flow structure around the hemispheres. The local bed shear stress field displayed substantial variability and controlled the bed load transport rates and direction in which sediment moved. The divergence in bed shear stress caused by the hemispheres promoted size-selective bed load deposition, which formed patches of coarse sediment upstream of the hemisphere. Sediment deposition caused a decrease in local bed shear stress, which combined with the coarser grain size, enhanced the stability of this patch. The region downstream of the hemispheres was largely controlled by a recirculation zone and had little to no change in grain size, bed elevation, and bed shear stress. The formation, development, and stability of sediment patches in mountain streams is controlled by the bed shear stress divergence and magnitude and direction of the local bed shear stress field.

  2. Decontamination of chemical tracers in droplets by a submerging thin film flow

    NASA Astrophysics Data System (ADS)

    Landel, Julien R.; McEvoy, Harry; Dalziel, Stuart B.

    2016-11-01

    We investigate the decontamination of chemical tracers contained in small viscous drops by a submerging falling film. This problem has applications in the decontamination of hazardous chemicals, following accidental releases or terrorist attacks. Toxic droplets lying on surfaces are cleaned by spraying a liquid decontaminant over the surface. The decontaminant film submerges the droplets, without detaching them, in order to neutralize toxic chemicals in the droplets. The decontamination process is controlled by advection, diffusion and reaction processes near the drop-film interface. Chemical tracers dissolve into the film flow forming a thin diffusive boundary layer at the interface. The chemical tracers are then neutralized through a reaction with a chemical decontaminant transported in the film. We assume in this work that the decontamination process occurs mainly in the film phase owing to low solubility of the decontaminant in the drop phase. We analyze the impact of the reaction time scale, assuming first-order reaction, in relation with the characteristic advection and diffusion time scales in the case of a single droplet. Using theoretical, numerical and experimental means, we find that the reaction time scale need to be significantly smaller than the characteristic time scale in the diffusive boundary layer in order to enhance noticeably the decontamination of a single toxic droplet. We discuss these results in the more general case of the decontamination of a large number of droplets. This material is based upon work supported by the Defense Threat Reduction Agency under Contract No. HDTRA1-12-D-0003-0001.

  3. Clementine, Deep Space Program Science Experiment

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Clementine, also called the Deep Space Program Science Experiment, is a joint Department of Defense (DoD)/National Aeronautics and Space Administration (NASA) mission with the dual goal of testing small spacecraft, subsystems, and sensors in the deep space environment and also providing a nominal science return. The Clementine mission will provide technical demonstrations of innovative lightweight spacecraft components and sensors, will be launced on a spacecraft developed within 2 years of program start, and will point a way for new planetary mission options under consideration by NASA. This booklet gives the background of the Clementine mission (including the agencies involved), the mission objectives, the mission scenario, the instruments that the mission will carry, and how the data will be analyzed and made accessible.

  4. 75 FR 35435 - Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-22

    .... 100513223-0254-01] RIN 0648-AY88 Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic Deep-Sea Red Crab Specifications In- season Adjustment AGENCY: National Marine... deep-sea red crab fishery, including a target total allowable catch (TAC) and a fleet-wide days-at-sea...

  5. Being There & Getting Back Again: Half a Century of Deep Ocean Research & Discovery with the Human Occupied Vehicle "Alvin"

    NASA Astrophysics Data System (ADS)

    German, C. R.; Fornari, D. J.; Fryer, P.; Girguis, P. R.; Humphris, S. E.; Kelley, D. S.; Tivey, M.; Van Dover, C. L.; Von Damm, K.

    2012-12-01

    In 2013, Alvin returns to service after significant observational and operational upgrades supported by the NSF, NAVSEA & NOAA. Here we review highlights of the first half-century of deep submergence science conducted by Alvin, describe some of the most significant improvements for the new submarine and discuss the importance of these new capabilities for 21st century ocean science and education. Alvin has a long history of scientific exploration, discovery and intervention at the deep seafloor: in pursuit of hypothesis-driven research and in response to human impacts. One of Alvin's earliest achievements, at the height of the Cold War, was to help locate & recover an H-bomb in the Mediterranean, while the last dives completed, just ahead of the current refit, were to investigate the impacts of the Deep Water Horizon oil spill. Alvin has excelled in supporting a range of Earth & Life Science programs including, in the late 1970s, first direct observations and sampling of deep-sea hydrothermal vents and the unusual fauna supported by microbial chemosynthesis. The 1980s saw expansion of Alvin's dive areas to newly discovered hot-springs in the Atlantic & NE Pacific, Alvin's first dives to the wreck of RMS Titanic and its longest excursions away from WHOI yet, via Loihi Seamount (Hawaii) to the Mariana Trench. The 1990s saw Alvin's first event-response dives to sites where volcanic eruptions had just occurred at the East Pacific Rise & Juan de Fuca Ridge while the 2000s saw Alvin discover novel off-axis venting at Lost City. Observations from these dives fundamentally changed our views of volcanic and microbial processes within young ocean crust and even the origins of life! In parallel, new deep submergence capabilities, including manipulative experiments & sensor development, relied heavily on testing using Alvin. Recently, new work has focused on ocean margins where fluid flow from the seafloor results in the release of hydrocarbons and other chemical species that

  6. Microstructural changes of a thermally aged stainless steel submerged arc weld overlay cladding of nuclear reactor pressure vessels

    NASA Astrophysics Data System (ADS)

    Takeuchi, T.; Kameda, J.; Nagai, Y.; Toyama, T.; Matsukawa, Y.; Nishiyama, Y.; Onizawa, K.

    2012-06-01

    The effect of thermal aging on microstructural changes in stainless steel submerged arc weld-overlay cladding of reactor pressure vessels was investigated using atom probe tomography (APT). In as-received materials subjected to post-welding heat treatments (PWHTs), with a subsequent furnace cooling, a slight fluctuation of the Cr concentration was observed due to spinodal decomposition in the δ-ferrite phase but not in the austenitic phase. Thermal aging at 400 °C for 10,000 h caused not only an increase in the amplitude of spinodal decomposition but also the precipitation of G phases with composition ratios of Ni:Si:Mn = 16:7:6 in the δ-ferrite phase. The degree of the spinodal decomposition in the submerged arc weld sample was similar to that in the electroslag weld one reported previously. We also observed a carbide on the γ-austenite and δ-ferrite interface. There were no Cr depleted zones around the carbide.

  7. Effect of high loading on substrate utilization kinetics and microbial community structure in super fast submerged membrane bioreactor.

    PubMed

    Sözen, S; Çokgör, E U; Başaran, S Teksoy; Aysel, M; Akarsubaşı, A; Ergal, I; Kurt, H; Pala-Ozkok, I; Orhon, D

    2014-05-01

    The study investigated the effect of high substrate loading on substrate utilization kinetics, and changes inflicted on the composition of the microbial community in a superfast submerged membrane bioreactor. Submerged MBR was sequentially fed with a substrate mixture and acetate; its performance was monitored at steady-state, at extremely low sludge age values of 2.0, 1.0 and 0.5d, all adjusted to a single hydraulic retention time of 8.0 h. Each MBR run was repeated when substrate feeding was increased from 200 mg COD/L to 1000 mg COD/L. Substrate utilization kinetics was altered to significantly lower levels when the MBR was adjusted to higher substrate loadings. Molecular analysis of the biomass revealed that variable process kinetics could be correlated with parallel changes in the composition of the microbial community, mainly by a replacement mechanism, where newer species, better adapted to the new growth conditions, substituted others that are washed out from the system. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. The discovery of deep-water seagrass meadows in a pristine Indian Ocean wilderness revealed by tracking green turtles.

    PubMed

    Esteban, N; Unsworth, R K F; Gourlay, J B Q; Hays, G C

    2018-03-21

    Our understanding of global seagrass ecosystems comes largely from regions characterized by human impacts with limited data from habitats defined as notionally pristine. Seagrass assessments also largely focus on shallow-water coastal habitats with comparatively few studies on offshore deep-water seagrasses. We satellite tracked green turtles (Chelonia mydas), which are known to forage on seagrasses, to a remote, pristine deep-water environment in the Western Indian Ocean, the Great Chagos Bank, which lies in the heart of one of the world's largest marine protected areas (MPAs). Subsequently we used in-situ SCUBA and baited video surveys to survey the day-time sites occupied by turtles and discovered extensive monospecific seagrass meadows of Thalassodendron ciliatum. At three sites that extended over 128 km, mean seagrass cover was 74% (mean range 67-88% across the 3 sites at depths to 29 m. The mean species richness of fish in seagrass meadows was 11 species per site (mean range 8-14 across the 3 sites). High fish abundance (e.g. Siganus sutor: mean MaxN.site -1  = 38.0, SD = 53.7, n = 5) and large predatory shark (Carcharhinus amblyrhynchos) (mean MaxN.site -1  = 1.5, SD = 0.4, n = 5) were recorded at all sites. Such observations of seagrass meadows with large top predators, are limited in the literature. Given that the Great Chagos Bank extends over approximately 12,500 km 2 and many other large deep submerged banks exist across the world's oceans, our results suggest that deep-water seagrass may be far more abundant than previously suspected. Copyright © 2018 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  9. Modelling of depth stabilization and submerging of tethered underwater garage in conditions of sea oscillating motion

    NASA Astrophysics Data System (ADS)

    Gayvoronskiy, S. A.; Ezangina, T. A.; Khozhaev, I. V.

    2018-03-01

    The paper is dedicated to examining dynamics of a submersible underwater garage in conditions of significant sea oscillation. During the considered research, the mathematical model of the electromechanical depth control system, considering interval parametric uncertainty of the system and distribution of tether mass, was developed. An influence of sea oscillation on submerging underwater garages and their depth stabilization processes was analyzed.

  10. Effects of hierarchical features on longevity of submerged superhydrophobic surfaces with parallel grooves

    NASA Astrophysics Data System (ADS)

    Hemeda, A. A.; Gad-el-Hak, M.; Tafreshi, H. Vahedi

    2014-08-01

    While the air-water interface over superhydrophobic surfaces decorated with hierarchical micro- or nanosized geometrical features have shown improved stability under elevated pressures, their underwater longevity—-the time that it takes for the surface to transition to the Wenzel state—-has not been studied. The current work is devised to study the effects of such hierarchical features on the longevity of superhydrophobic surfaces. For the sake of simplicity, our study is limited to superhydrophobic surfaces composed of parallel grooves with side fins. The effects of fins on the critical pressure—-the pressure at which the surface starts transitioning to the Wenzel state—-and longevity are predicted using a mathematical approach based on the balance of forces across the air-water interface. Our results quantitatively demonstrate that the addition of hierarchical fins significantly improves the mechanical stability of the air-water interface, due to the high advancing contact angles that can be achieved when an interface comes in contact with the fins sharp corners. For longevity on the contrary, the hierarchical fins were only effective at hydrostatic pressures below the critical pressure of the original smooth-walled groove. Our results indicate that increasing the length of the fins decreases the critical pressure of a submerged superhydrophobic groove but increases its longevity. Increasing the thickness of the fins can improve both the critical pressure and longevity of a submerged groove. The mathematical framework presented in this paper can be used to custom-design superhydrophobic surfaces for different applications.

  11. Deep-Sea Research Submarine 'Ben Franklin' at the East Coast of the United States

    NASA Technical Reports Server (NTRS)

    1969-01-01

    In this photograph, the deep-sea Research Submarine 'Ben Franklin' drifts off the East Coast of the United States (U.S.) prior to submerging into the ocean. Named for American patriot and inventor Ben Franklin, who discovered the Gulf Steam, the 50-foot Ben Franklin was built between 1966 and 1968 in Switzerland for deep-ocean explorer Jacques Piccard and the Grumman Aircraft Engineering Corporation. The submersible made a famous 30-day drift dive off the East Coast of the United States and Canada in 1969 mapping the Gulf Stream's currents and sea life, and also made space exploration history by studying the behavior of aquanauts in a sealed, self-contained, self-sufficient capsule for NASA. On July 14, 1969, the Ben Franklin was towed to the high-velocity center of the Stream off the coast of Palm Beach, Florida. With a NASA observer on board, the sub descended to 1,000 feet off of Riviera Beach, Florida and drifted 1,400 miles north with the current for more than four weeks, reemerging near Maine. During the course of the dive, NASA conducted exhaustive analyses of virtually every aspect of onboard life. They measured sleep quality and patterns, sense of humor and behavioral shifts, physical reflexes, and the effects of a long-term routine on the crew. The submarine's record-shattering dive influenced the design of Apollo and Skylab missions and continued to guide NASA scientists as they devised future marned space-flight missions.

  12. Visit to the Deep Underground Science and Engineering Laboratory

    ScienceCinema

    None

    2017-12-09

    U.S. Department of Energy scientists and administrators join members of the National Science Foundation and South Dakotas Sanford Underground Laboratory for the deepest journey yet to the proposed site of the Deep Underground Science and Engineering Laboratory (DUSEL).

  13. Visit to the Deep Underground Science and Engineering Laboratory

    ScienceCinema

    None

    2018-05-16

    U.S. Department of Energy scientists and administrators join members of the National Science Foundation and South Dakotas Sanford Underground Laboratory for the deepest journey yet to the proposed site of the Deep Underground Science and Engineering Laboratory (DUSEL).

  14. Emerging and Submerging Shorelines: Impacts of Physical Change on Bioband Length

    NASA Astrophysics Data System (ADS)

    Kruger, L. E.; Johnson, A. C.; Gregovich, D.; Buma, B.; Noel, J.

    2017-12-01

    We approximated shifts in coastal benthic species for shoreline length units undergoing both sea level rise and relative sea level lowering (often post-glacial, termed isostatic rebound) where subsistence-based, southeast Alaska Natives reside. From six community centers, we examined 30 km radii shoreline reaches by merging relevant portions of the NOAA ShoreZone database with near shore bathymetry and measures of mean global sea level rise with local global positioning system information (GIS) of tectonic shift and isostatic rebound. For our analysis, we estimated change for 9,868 assessed shoreline length units having uniform substrate and biologic type over a 100-yr time span (2008-2108) using geometric analysis of shoreline attributes. For each shoreline length unit we assessed relationships among substrate, slope, exposure, and presence of five benthic species including eel grass (Zostera marina), blue mussel (Mytilus edulis), butter clams (Saxidomus gigantean), bull kelp (Nereocytis leutkeana), and foliose red algae including ribbon kelp (Palmaria sp.). Our research indicates that both emergence, up to 1.8 m, and submergence, up 0.2 m, of the land will result in disportionately larger shoreline length segment alterations for habitats in protected low-slope gradient bays and estuaries (dominated by eelgrass and butter clam habitats) with less change for rocky steep-gradient exposed penninsulas (red algae and canopy kelp). This trend, holding true regardless of isostatic rebound, tectonic shift or sea level rise rate, highlights the importance of initial geomorphology-based assessments serving to improve bio-physical, chemical, and socially-related coastal research. Where shorelines are emerging 30% decreases in estuary lengths are predicted, but where shorelines are submerging up to 3% increases in estuaries are expected. Our research results are consistent with anthropology studies assessing past coastal change. Coastal change, influencing subsistance foods

  15. Submerged Macrophytes Mitigate Direct and Indirect Insecticide Effects in Freshwater Communities

    PubMed Central

    Brogan, William R.; Relyea, Rick A.

    2015-01-01

    Understanding how ecological interactions mitigate the impacts of perturbations such as pesticides in biological communities is an important basic and applied question for ecologists. In aquatic ecosystems, new evidence from microcosm experiments suggests that submerged macrophytes can buffer cladocerans from pulse exposures to the widely used insecticide malathion, and that mitigation increases with macrophyte density. However, whether these results scale up to more complex aquatic communities where ecological interactions such as competition can alter toxicity is unknown. Further, macrophyte abilities to mitigate different insecticide exposure scenarios (i.e. single versus repeated pulses) have never been tested. To address these gaps, we performed a factorial mesocosm experiment examining the influence of four macrophyte treatments (0, 10, 50, or 100 Elodea Canadensis shoots planted per mesocosm) crossed with three malathion exposure scenarios (no insecticide, single pulse, repeated pulses) on aquatic communities containing zooplankton, phytoplankton, periphyton, two snail species, and larval amphibians. In the absence of macrophytes, single malathion pulses caused short-term declines in cladoceran abundance followed by their rapid recovery, which precluded any indirect effects (i.e. trophic cascades). However, repeated malathion pulses caused cladoceran extinctions, resulting in persistent phytoplankton blooms and reduced abundance of one snail species. In contrast, with macrophytes present, even at low density, malathion had no effect on any taxa. We also discovered novel effects of macrophytes on the benthic food web. In the two highest macrophyte treatments, we observed trends of reduced periphyton biomass, decreased abundance of one snail species, and decreased amphibian time to and mass at metamorphosis. To our knowledge, this is the first evidence of negative submerged macrophyte effects on amphibians, a taxa of global conservation concern. Our findings

  16. Response of biofilms-leaves of two submerged macrophytes to high ammonium.

    PubMed

    Gong, Lixue; Zhang, Songhe; Chen, Deqiang; Liu, Kaihui; Lu, Jian

    2018-02-01

    Submerged macrophytes can provide attached surface for biofilms (known as periphyton) growth. In the present study, the alterations in biofilms formation, and chemical compositions and physiological responses were investigated on leaves of Vallisneria asiatica and Hydrilla verticillata exposed to 0.1 mg L -1 (control) or with 10 mg L -1 NH 4 + -N for 13 days. Results from physiological and biochemical indices (content of H 2 O 2 , malondialdehyde, total chlorophyll and activity of superoxide dismutase, catalase and peroxidase) showed that high ammonium caused oxidative damage to leaves of two species of plant. Multifractal analysis (based on scanning electron microscope images) showed that for the same plant, the values of width △α (△α = α max -α min ) of the f(α) and Δf (Δf = f(α min )-f(α max )) were smaller on leaves surface of two species of plant treated with 10 mg L -1 NH 4 + -N for 13 days than their controls, suggesting high ammonium treatments reduced morphological heterogeneity of leaf surface and enhanced area of the colony-like biofilms. X-ray photoelectron spectroscopy analysis showed that C, O, N and P were dominant elements on leaves surface of two species of plant and ammonium application increased the percentage of C but decreased that of O. High ammonium increased C1 (C-C or C-H) percentage but decreased C2 (C-O) and C3 (O-C-O or C=O) percentage on leaves surface of two species of plant, indicating that ammonium stress changed the surface chemical states and thus might reduce the capacity of leaves to adsorb nutrients from water column. Our results provided useful information to understand ammonium induced toxicity to submerged macrophytes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Excess plutonium disposition: The deep borehole option

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ferguson, K.L.

    1994-08-09

    This report reviews the current status of technologies required for the disposition of plutonium in Very Deep Holes (VDH). It is in response to a recent National Academy of Sciences (NAS) report which addressed the management of excess weapons plutonium and recommended three approaches to the ultimate disposition of excess plutonium: (1) fabrication and use as a fuel in existing or modified reactors in a once-through cycle, (2) vitrification with high-level radioactive waste for repository disposition, (3) burial in deep boreholes. As indicated in the NAS report, substantial effort would be required to address the broad range of issues relatedmore » to deep bore-hole emplacement. Subjects reviewed in this report include geology and hydrology, design and engineering, safety and licensing, policy decisions that can impact the viability of the concept, and applicable international programs. Key technical areas that would require attention should decisions be made to further develop the borehole emplacement option are identified.« less

  18. Sequoia National Park

    NASA Image and Video Library

    2017-12-08

    Naked peaks, sheltered valleys, snowfields, towering trees, and alpine meadows make up the varied landscape of Sequoia National Park in California. Established as a National Park by Congress on September 25, 1890, Sequoia National Park is the second-oldest U.S. National Park, after Yellowstone. This national park borders Kings Canyon National Park. The Thematic Mapper sensor on NASA’s Landsat 5 satellite captured this true-color image of Sequoia National Park, outlined in white, on October 22, 2008. Sunlight illuminates southern slopes, leaving northern faces in shadow in this autumn image. In the west, deep green conifers carpet most of the land. These forested mountains are home to the park’s most famous giant sequoia trees. Sequoia National Park sits at the southern end of the Sierra Nevada mountains. Terrain alternates between extremes, from peaks such as Mt. Whitney—the highest peak in the contiguous United States—to deep caverns. The rivers and lakes in this region are part of a watershed valuable not only to the plants and animals of the park, but also to farms and cities in California’s Central Valley. Read more: go.nasa.gov/2bzGOXr Credit: NASA/Landsat5 NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  19. Lectin activity of species of genus Cerrena S.F. Gray (Aphyllophoromycetideae) in submerged fermentation of lignocellulosic materials.

    PubMed

    Davitashvili, Elene; Kapanadze, Ekaterine; Kachlishvili, Eva; Elisashvili, Vladimir

    2011-01-01

    The capability of 5 strains of 2 species of genus Cerrena (Aphyllophoromycetideae) to express hemagglutinating activity (HA) was evaluated in submerged fermentation of 7 lignocellulosic materials of different chemical compositions. Among the lignocellulosic substrates tested, walnut pericarp, followed by mandarin and kiwi peels provided the highest specific HA of C. unicolor IBB 300; walnut leaves and pericarp appeared to be the best substrates for the accumulation of lectin by C. unicolor IBB 301, whereas the fermentation of kiwi peels ensured the highest HA of C. unicolor IBB 302. The highest HA was detected in C. maxima IBB 402 cultivation in submerged fermentation of walnut leaves (64103 U/mg), mandarin (33333 U/mg) and kiwi peels (28571 U/mg). Moreover, the fermentation of walnut pericarp and leaves provided the secretion of high lectin levels in culture liquid (9143 U/mg). The carbohydrate specificity of tested preparations significantly depended on both fungus strain and lignocellulosic growth substrate. By substitution of lignocellulosic material, it is possible to regulate lectin production and to obtain a preparation with different specificity toward carbohydrates.

  20. AN EXPERT SYSTEM FOR HYDRODYNAMIC MIXING ZONE ANAYLSIS OF CONVENTIONAL AND TOXIC SUBMERGED SINGLE PORT DISCHARGES (CORMIX1)

    EPA Science Inventory

    U.S. water quality policy includes the concept of a mixing zone, a limited area or volume of water where the initial dilution of a discharge occurs. he Cornell Mixing Zone Expert System (CORMIX1) was developed to predict the dilution and trajectory of a submerged single port disc...

  1. Xylanase production by a newly isolated Aspergillus niger SS7 in submerged culture.

    PubMed

    Bakri, Yasser; Al-Jazairi, Manal; Al-Kayat, Ghassan

    2008-01-01

    Xylanase production by a newly isolated Aspergillus niger SS7 was studied in submerged culture. The optimum initial pH for xylanase production was found to be 7.0. Different agricultural and industrial wastes were evaluated for their ability to induce xylanase production by this isolate. The best xylanase production (293.82 IU/ml) was recorded at 3% (w/v) corn cob hulls after 120 h of incubation. The Aspergillus niger SS7 isolate grown in a simple medium, proved to be a promising microorganism for xylanase production.

  2. Three-Dimensional Flow Behavior Inside the Submerged Entry Nozzle

    NASA Astrophysics Data System (ADS)

    Real-Ramirez, Cesar Augusto; Carvajal-Mariscal, Ignacio; Sanchez-Silva, Florencio; Cervantes-de-la-Torre, Francisco; Diaz-Montes, Jesus; Gonzalez-Trejo, Jesus

    2018-05-01

    According to various authors, the surface quality of steel depends on the dynamic conditions that occur within the continuous casting mold's upper region. The meniscus, found in that upper region, is where the solidification process begins. The liquid steel is distributed into the mold through a submerged entry nozzle (SEN). In this paper, the dynamic behavior inside the SEN is analyzed by means of physical experiments and numerical simulations. The particle imaging velocimetry technique was used to obtain the vector field in different planes and three-dimensional flow patterns inside the SEN volume. Moreover, large eddy simulation was performed, and the turbulence model results were used to understand the nonlinear flow pattern inside the SEN. Using scaled physical and numerical models, quasi-periodic behavior was observed due to the interaction of two three-dimensional vortices that move inside the SEN lower region located between the exit ports of the nozzle.

  3. Wakes from submerged obstacles in an open channel flow

    NASA Astrophysics Data System (ADS)

    Smith, Geoffrey B.; Marmorino, George; Dong, Charles; Miller, W. D.; Mied, Richard

    2015-11-01

    Wakes from several submerged obstacles are examined via airborne remote sensing. The primary focus will be bathymetric features in the tidal Potomac river south of Washington, DC, but others may be included as well. In the Potomac the water depth is nominally 10 m with an obstacle height of 8 m, or 80% of the depth. Infrared imagery of the water surface reveals thermal structure suitable both for interpretation of the coherent structures and for estimating surface currents. A novel image processing technique is used to generate two independent scenes with a known time offset from a single overpass from the infrared imagery, suitable for velocity estimation. Color imagery of the suspended sediment also shows suitable texture. Both the `mountain wave' regime and a traditional turbulent wake are observed, depending on flow conditions. Results are validated with in-situ ADCP transects. A computational model is used to further interpret the results.

  4. Phytoremediation of arsenic in submerged soil by wetland plants.

    PubMed

    Jomjun, Nateewattana; Siripen, Trichaiyaporn; Maliwan, Saeouy; Jintapat, Nateewattana; Prasak, Thavornyutikarn; Somporn, Choonluchanon; Petch, Pengchai

    2011-01-01

    Wetland aquatic plants including Canna glauca L., Colocasia esculenta L. Schott, Cyperus papyrus L. and Typha angustifolia L. were used in the phytoremediation of submerged soil polluted by arsenic (As). Cyperus papyrus L. was noticed as the largest biomass producer which has arsenic accumulation capacity of 130-172 mg As/kg plant. In terms of arsenic removal rate, however, Colocasia esculenta L. was recognized as the largest and fastest arsenic remover in this study. Its arsenic removal rate was 68 mg As/m2/day while those rates of Canna glauca L., Cyperus papyrus L. and Typha angustifolia L. were 61 mg As/m2/day, 56 mg As/m2/day, and 56 mg As/m2/day, respectively. Although the 4 aquatic plants were inferior in arsenic accumulation, their high arsenic removal rates were observed. Phytostabilization should be probable for the application of these plants.

  5. A new approach on anti-vortex devices at water intakes including a submerged water jet

    NASA Astrophysics Data System (ADS)

    Tahershamsi, Ahmad; Rahimzadeh, Hassan; Monshizadeh, Morteza; Sarkardeh, Hamed

    2018-04-01

    A new approach on anti-vortex methods as hydraulic-based anti-vortex was investigated experimentally in the present study. In the investigated method, a submerged water jet is used as the anti-vortex mechanism. The added jet acts as a source of external momentum. This leads to change the intake-induced hydrodynamic pattern in the near-field of the intake structure, which can prevent formation of undesirable intake vortices. The experiments were carried out on a horizontal pipe intake. By performing 570 test cases in two different categories, including the inclined jet with respect to the axis of the intake, and the inclined jet with respect to the water surface, the effects of the jet inclination angle on the anti-vortex performance were investigated. It was found that the inclined jet with respect to the water surface is the best alternative to consider as the water jet injection pattern. Results showed that using the inclined jet with respect to the water surface can simply reduce the amounts of the expected water jet momentum more than 50% compared to that of the similar condition of the horizontal injection pattern. Moreover, it was concluded that the intake critical submergence can easily be minimized using the inclined jet with respect to the water surface.

  6. Experimental study to control the upstream migration of invasive alien fish species by submerged weir

    NASA Astrophysics Data System (ADS)

    Sakuma, Masami; Kunimatsu, Fumihiro; Tsuchiya, Taku; Kawamura, Makiko; Fujita, Hiroshi

    Largemouth bass and Bluegill, major invasive alien fish species in Japan, have been extending their habitat ranges over not only Lake Biwa and the lagoons but also surrounding waters connected to them through small rivers and canals. Their increasing number is bringing about the reduction in the number of native fish species. To prevent the spread of these alien species through small rivers and canals during breeding season of the native fish (crucian carp), this study experimentally examined the effect of a submerged weir on controlling upstream migration of the alien species and the native fish. As a result of the experiment, the ratio of the alien species migrating upstream decreased as the weir height rose, whereas the ratio did not show the same trend in the case of the native fish. The ratio of the alien species also decreased as the overflow velocity over the weir rose. On the other hand, the ratio of the native fish increased as the overflow velocity rose up to 1.0m/s and decreased thereafter. These results suggest that the submerged weir may control upstream migration of the alien species to surrounding waters through small rivers and canals without interfering with the reproductive migration of the native fish.

  7. Stem Cubic-Volume Tables for Tree Species in the Deep South Area

    Treesearch

    Alexander Clark; Ray A. Souter

    1996-01-01

    Stemwood cubic-foot volume inside bark tables are presented for 21 species and 8 species groups based on equations used to estimate timber sale volumes on national forests in the Deep South Area. Tables are based on form class measurement data for 2,390 trees sampled in the Deep South Area and taper data collected across the South. A series of tables is presented for...

  8. Secretome analysis of Trichoderma reesei and Aspergillus niger cultivated by submerged and sequential fermentation processes: Enzyme production for sugarcane bagasse hydrolysis.

    PubMed

    Florencio, Camila; Cunha, Fernanda M; Badino, Alberto C; Farinas, Cristiane S; Ximenes, Eduardo; Ladisch, Michael R

    2016-08-01

    Cellulases and hemicellulases from Trichoderma reesei and Aspergillus niger have been shown to be powerful enzymes for biomass conversion to sugars, but the production costs are still relatively high for commercial application. The choice of an effective microbial cultivation process employed for enzyme production is important, since it may affect titers and the profile of protein secretion. We used proteomic analysis to characterize the secretome of T. reesei and A. niger cultivated in submerged and sequential fermentation processes. The information gained was key to understand differences in hydrolysis of steam exploded sugarcane bagasse for enzyme cocktails obtained from two different cultivation processes. The sequential process for cultivating A. niger gave xylanase and β-glucosidase activities 3- and 8-fold higher, respectively, than corresponding activities from the submerged process. A greater protein diversity of critical cellulolytic and hemicellulolytic enzymes were also observed through secretome analyses. These results helped to explain the 3-fold higher yield for hydrolysis of non-washed pretreated bagasse when combined T. reesei and A. niger enzyme extracts from sequential fermentation were used in place of enzymes obtained from submerged fermentation. An enzyme loading of 0.7 FPU cellulase activity/g glucan was surprisingly effective when compared to the 5-15 times more enzyme loadings commonly reported for other cellulose hydrolysis studies. Analyses showed that more than 80% consisted of proteins other than cellulases whose role is important to the hydrolysis of a lignocellulose substrate. Our work combined proteomic analyses and enzymology studies to show that sequential and submerged cultivation methods differently influence both titers and secretion profile of key enzymes required for the hydrolysis of sugarcane bagasse. The higher diversity of feruloyl esterases, xylanases and other auxiliary hemicellulolytic enzymes observed in the enzyme

  9. 78 FR 72060 - Chimney Rock National Monument Management Plan; San Juan National Forest; Colorado

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-02

    ..., as well as objects of deep cultural and educational value. The plan will also provide for continued... Ranger District office in Pagosa Springs, Colorado, and on the San Juan National Forest Web site at www..., direct mailings, emails, and will be posted on the San Juan National Forest Web site. It is important...

  10. A Servicewide Benthic Mapping Program for National Parks

    USGS Publications Warehouse

    Moses, Christopher S.; Nayegandhi, Amar; Beavers, Rebecca; Brock, John

    2010-01-01

    In 2007, the National Park Service (NPS) Inventory and Monitoring Program directed the initiation of a benthic habitat mapping program in ocean and coastal parks in alignment with the NPS Ocean Park Stewardship 2007-2008 Action Plan. With 74 ocean and Great Lakes parks stretching over more than 5,000 miles of coastline across 26 States and territories, this Servicewide Benthic Mapping Program (SBMP) is essential. This program will deliver benthic habitat maps and their associated inventory reports to NPS managers in a consistent, servicewide format to support informed management and protection of 3 million acres of submerged National Park System natural and cultural resources. The NPS and the U.S. Geological Survey (USGS) convened a workshop June 3-5, 2008, in Lakewood, Colo., to discuss the goals and develop the design of the NPS SBMP with an assembly of experts (Moses and others, 2010) who identified park needs and suggested best practices for inventory and mapping of bathymetry, benthic cover, geology, geomorphology, and some water-column properties. The recommended SBMP protocols include servicewide standards (such as gap analysis, minimum accuracy, final products) as well as standards that can be adapted to fit network and park unit needs (for example, minimum mapping unit, mapping priorities). SBMP Mapping Process. The SBMP calls for a multi-step mapping process for each park, beginning with a gap assessment and data mining to determine data resources and needs. An interagency announcement of intent to acquire new data will provide opportunities to leverage partnerships. Prior to new data acquisition, all involved parties should be included in a scoping meeting held at network scale. Data collection will be followed by processing and interpretation, and finally expert review and publication. After publication, all digital materials will be archived in a common format. SBMP Classification Scheme. The SBMP will map using the Coastal and Marine Ecological

  11. Spectral wave dissipation by submerged aquatic vegetation in a back-barrier estuary

    USGS Publications Warehouse

    Nowacki, Daniel J.; Beudin, Alexis; Ganju, Neil K.

    2017-01-01

    Submerged aquatic vegetation is generally thought to attenuate waves, but this interaction remains poorly characterized in shallow-water field settings with locally generated wind waves. Better quantification of wave–vegetation interaction can provide insight to morphodynamic changes in a variety of environments and also is relevant to the planning of nature-based coastal protection measures. Toward that end, an instrumented transect was deployed across a Zostera marina (common eelgrass) meadow in Chincoteague Bay, Maryland/Virginia, U.S.A., to characterize wind-wave transformation within the vegetated region. Field observations revealed wave-height reduction, wave-period transformation, and wave-energy dissipation with distance into the meadow, and the data informed and calibrated a spectral wave model of the study area. The field observations and model results agreed well when local wind forcing and vegetation-induced drag were included in the model, either explicitly as rigid vegetation elements or implicitly as large bed-roughness values. Mean modeled parameters were similar for both the explicit and implicit approaches, but the spectral performance of the explicit approach was poor compared to the implicit approach. The explicit approach over-predicted low-frequency energy within the meadow because the vegetation scheme determines dissipation using mean wavenumber and frequency, in contrast to the bed-friction formulations, which dissipate energy in a variable fashion across frequency bands. Regardless of the vegetation scheme used, vegetation was the most important component of wave dissipation within much of the study area. These results help to quantify the influence of submerged aquatic vegetation on wave dynamics in future model parameterizations, field efforts, and coastal-protection measures.

  12. Bacterial Production and Enzymatic Activities in Deep-Sea Sediments of the Pacific Ocean: Biogeochemical Implications of Different Temperature Constraints

    NASA Astrophysics Data System (ADS)

    Danovaro, R.; Corinaldesi, C.; dell'Anno, A.

    2002-12-01

    The deep-sea bed, acting as the ultimate sink for organic material derived from the upper oceans primary production, is now assumed to play a key role in biogeochemical cycling of organic matter on global scale. Early diagenesis of organic matter in marine sediments is dependent upon biological processes (largely mediated by bacterial activity) and by molecular diffusion. Organic matter reaching the sea floor by sedimentation is subjected to complex biogeochemical transformations that make organic matter largely unsuitable for direct utilization by benthic heterotrophs. Extracellular enzymatic activities in the sediment is generally recognized as the key step in the degradation and utilization of organic polymers by bacteria and a key role in biopolymeric carbon mobilization is played by aminopeptidase, alkaline phosphatase and glucosidase activities. In the present study we investigated bacterial density, bacterial C production and exo-enzymatic activities (aminopeptidase, glucosidase and phosphatase activity) in deep-sea sediments of the Pacific Ocean in relation with the biochemical composition of sediment organic matter (proteins, carbohydrates and lipids), in order to gather information on organic matter cycling and diagenesis. Benthic viral abundance was also measured to investigate the potential role of viruses on microbial loop functioning. Sediment samples were collected at eight stations (depth ranging from 2070-3100 m) along two transects located at the opposite side (north and south) of ocean seismic ridge Juan Fernandez (along latitudes 33° 20' - 33° 40'), constituted by the submerged vulcanoes, which connects the Chilean coasts to Rapa Nui Island. Since the northern and southern sides of this ridge apparently displayed small but significant differences in deep-sea temperature (related to the general ocean circulation), this sampling strategy allowed also investigating the role of different temperature constraints on bacterial activity and

  13. Characterization Efforts in a Deep Borehole Field Test

    NASA Astrophysics Data System (ADS)

    Kuhlman, K. L.; Sassani, D.; Freeze, G. A.; Hardin, E. L.; Brady, P. V.

    2016-12-01

    The US Department of Energy Office of Nuclear Energy is embarking on a Deep Borehole Field Test to investigate the feasibility of constructing and characterizing two boreholes in crystalline basement rock to a depth of 5 km (16,400 ft). The concept of deep borehole disposal for radioactive waste has some advantages, including incremental construction and loading and the enhanced natural barriers provided by deep continental crystalline basement. Site characterization activities will include geomechanical (i.e., hydrofracture stress measurements), geological (i.e., core and mud logging), hydrological (i.e., packer-based pulse and pumping tests), and chemical (i.e., fluids sampled in situ from packer intervals and extracted from cores) tests. Borehole-based characterization will be used to determine the variability of system state (i.e., stress, pressure, temperature, and chemistry) with depth and interpretation of material and system parameters relevant to numerical site simulation. We explore the effects fluid density and geothermal temperature gradients (i.e., thermohaline convection) have on characterization goals in light of expected downhole conditions, including a disturbed rock zone surrounding the borehole. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the US Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  14. Deep learning of unsteady laminar flow over a cylinder

    NASA Astrophysics Data System (ADS)

    Lee, Sangseung; You, Donghyun

    2017-11-01

    Unsteady flow over a circular cylinder is reconstructed using deep learning with a particular emphasis on elucidating the potential of learning the solution of the Navier-Stokes equations. A deep neural network (DNN) is employed for deep learning, while numerical simulations are conducted to produce training database. Instantaneous and mean flow fields which are reconstructed by deep learning are compared with the simulation results. Fourier transform of flow variables has been conducted to validate the ability of DNN to capture both amplitudes and frequencies of flow motions. Basis decomposition of learned flow is performed to understand the underlying mechanisms of learning flow through DNN. The present study suggests that a deep learning technique can be utilized for reconstruction and, potentially, for prediction of fluid flow instead of solving the Navier-Stokes equations. This work was supported by the National Research Foundation of Korea(NRF) Grant funded by the Korea government(Ministry of Science, ICT and Future Planning) (No. 2014R1A2A1A11049599, No. 2015R1A2A1A15056086, No. 2016R1E1A2A01939553).

  15. Opportunities and challenges in studies of deep life (Invited)

    NASA Astrophysics Data System (ADS)

    Edwards, K. J.

    2010-12-01

    Over the past two decades, there has been an increasing awareness within the geological, microbiological, and oceanographic communities of the potentially vast microbial biosphere that is harbored beneath the surface of the Earth. With this awareness has come a mounting effort to study this potential biome - to better quantify biomass abundance, activity, and biogeochemical activity. In the Earth system, the largest deep subsurface biome is also the least accessible - the deep ocean subsurface biosphere. The oceanic deep biosphere also has greatest potential for influencing global scale biogeochemical processes -the carbon and energy cycles for example, and other elemental cycles. To address these topics and mount interdisciplinary efforts to study the deep subsurface marine biosphere, we have recently formed a center in support integrative, collaborative investigations. The national science foundation Center for Dark Biosphere Investigations (C-DEBI), has been initiated for the explicit purpose of resolving the extent, function, dynamics and implications of the subseafloor biosphere. This talk will discuss C-DEBI science, with focus on some of the opportunities and challenges in the study of deep life in the ocean, and the role that C-DEBI will play in meeting them

  16. Accurate Determination of the Frequency Response Function of Submerged and Confined Structures by Using PZT-Patches †

    PubMed Central

    Presas, Alexandre; Valentin, David; Egusquiza, Eduard; Valero, Carme; Egusquiza, Mònica; Bossio, Matias

    2017-01-01

    To accurately determine the dynamic response of a structure is of relevant interest in many engineering applications. Particularly, it is of paramount importance to determine the Frequency Response Function (FRF) for structures subjected to dynamic loads in order to avoid resonance and fatigue problems that can drastically reduce their useful life. One challenging case is the experimental determination of the FRF of submerged and confined structures, such as hydraulic turbines, which are greatly affected by dynamic problems as reported in many cases in the past. The utilization of classical and calibrated exciters such as instrumented hammers or shakers to determine the FRF in such structures can be very complex due to the confinement of the structure and because their use can disturb the boundary conditions affecting the experimental results. For such cases, Piezoelectric Patches (PZTs), which are very light, thin and small, could be a very good option. Nevertheless, the main drawback of these exciters is that the calibration as dynamic force transducers (relationship voltage/force) has not been successfully obtained in the past. Therefore, in this paper, a method to accurately determine the FRF of submerged and confined structures by using PZTs is developed and validated. The method consists of experimentally determining some characteristic parameters that define the FRF, with an uncalibrated PZT exciting the structure. These parameters, which have been experimentally determined, are then introduced in a validated numerical model of the tested structure. In this way, the FRF of the structure can be estimated with good accuracy. With respect to previous studies, where only the natural frequencies and mode shapes were considered, this paper discuss and experimentally proves the best excitation characteristic to obtain also the damping ratios and proposes a procedure to fully determine the FRF. The method proposed here has been validated for the structure vibrating

  17. Tractography patterns of subthalamic nucleus deep brain stimulation.

    PubMed

    Vanegas-Arroyave, Nora; Lauro, Peter M; Huang, Ling; Hallett, Mark; Horovitz, Silvina G; Zaghloul, Kareem A; Lungu, Codrin

    2016-04-01

    Deep brain stimulation therapy is an effective symptomatic treatment for Parkinson's disease, yet the precise mechanisms responsible for its therapeutic effects remain unclear. Although the targets of deep brain stimulation are grey matter structures, axonal modulation is known to play an important role in deep brain stimulation's therapeutic mechanism. Several white matter structures in proximity to the subthalamic nucleus have been implicated in the clinical benefits of deep brain stimulation for Parkinson's disease. We assessed the connectivity patterns that characterize clinically beneficial electrodes in Parkinson's disease patients, after deep brain stimulation of the subthalamic nucleus. We evaluated 22 patients with Parkinson's disease (11 females, age 57 ± 9.1 years, disease duration 13.3 ± 6.3 years) who received bilateral deep brain stimulation of the subthalamic nucleus at the National Institutes of Health. During an initial electrode screening session, one month after deep brain stimulation implantation, the clinical benefits of each contact were determined. The electrode was localized by coregistering preoperative magnetic resonance imaging and postoperative computer tomography images and the volume of tissue activated was estimated from stimulation voltage and impedance. Brain connectivity for the volume of tissue activated of deep brain stimulation contacts was assessed using probabilistic tractography with diffusion-tensor data. Areas most frequently connected to clinically effective contacts included the thalamus, substantia nigra, brainstem and superior frontal gyrus. A series of discriminant analyses demonstrated that the strength of connectivity to the superior frontal gyrus and the thalamus were positively associated with clinical effectiveness. The connectivity patterns observed in our study suggest that the modulation of white matter tracts directed to the superior frontal gyrus and the thalamus is associated with favourable clinical

  18. Spectrum response estimation for deep-water floating platforms via retardation function representation

    NASA Astrophysics Data System (ADS)

    Liu, Fushun; Liu, Chengcheng; Chen, Jiefeng; Wang, Bin

    2017-08-01

    The key concept of spectrum response estimation with commercial software, such as the SESAM software tool, typically includes two main steps: finding a suitable loading spectrum and computing the response amplitude operators (RAOs) subjected to a frequency-specified wave component. In this paper, we propose a nontraditional spectrum response estimation method that uses a numerical representation of the retardation functions. Based on estimated added mass and damping matrices of the structure, we decompose and replace the convolution terms with a series of poles and corresponding residues in the Laplace domain. Then, we estimate the power density corresponding to each frequency component using the improved periodogram method. The advantage of this approach is that the frequency-dependent motion equations in the time domain can be transformed into the Laplace domain without requiring Laplace-domain expressions for the added mass and damping. To validate the proposed method, we use a numerical semi-submerged pontoon from the SESAM. The numerical results show that the responses of the proposed method match well with those obtained from the traditional method. Furthermore, the estimated spectrum also matches well, which indicates its potential application to deep-water floating structures.

  19. Exploring the Earth Using Deep Learning Techniques

    NASA Astrophysics Data System (ADS)

    Larraondo, P. R.; Evans, B. J. K.; Antony, J.

    2016-12-01

    Research using deep neural networks have significantly matured in recent times, and there is now a surge in interest to apply such methods to Earth systems science and the geosciences. When combined with Big Data, we believe there are opportunities for significantly transforming a number of areas relevant to researchers and policy makers. In particular, by using a combination of data from a range of satellite Earth observations as well as computer simulations from climate models and reanalysis, we can gain new insights into the information that is locked within the data. Global geospatial datasets describe a wide range of physical and chemical parameters, which are mostly available using regular grids covering large spatial and temporal extents. This makes them perfect candidates to apply deep learning methods. So far, these techniques have been successfully applied to image analysis through the use of convolutional neural networks. However, this is only one field of interest, and there is potential for many more use cases to be explored. The deep learning algorithms require fast access to large amounts of data in the form of tensors and make intensive use of CPU in order to train its models. The Australian National Computational Infrastructure (NCI) has recently augmented its Raijin 1.2 PFlop supercomputer with hardware accelerators. Together with NCI's 3000 core high performance OpenStack cloud, these computational systems have direct access to NCI's 10+ PBytes of datasets and associated Big Data software technologies (see http://geonetwork.nci.org.au/ and http://nci.org.au/systems-services/national-facility/nerdip/). To effectively use these computing infrastructures requires that both the data and software are organised in a way that readily supports the deep learning software ecosystem. Deep learning software, such as the open source TensorFlow library, has allowed us to demonstrate the possibility of generating geospatial models by combining information from

  20. Underwater photosynthesis of submerged plants - recent advances and methods.

    PubMed

    Pedersen, Ole; Colmer, Timothy D; Sand-Jensen, Kaj

    2013-01-01

    We describe the general background and the recent advances in research on underwater photosynthesis of leaf segments, whole communities, and plant dominated aquatic ecosystems and present contemporary methods tailor made to quantify photosynthesis and carbon fixation under water. The majority of studies of aquatic photosynthesis have been carried out with detached leaves or thalli and this selectiveness influences the perception of the regulation of aquatic photosynthesis. We thus recommend assessing the influence of inorganic carbon and temperature on natural aquatic communities of variable density in addition to studying detached leaves in the scenarios of rising CO2 and temperature. Moreover, a growing number of researchers are interested in tolerance of terrestrial plants during flooding as torrential rains sometimes result in overland floods that inundate terrestrial plants. We propose to undertake studies to elucidate the importance of leaf acclimation of terrestrial plants to facilitate gas exchange and light utilization under water as these acclimations influence underwater photosynthesis as well as internal aeration of plant tissues during submergence.

  1. Natural air leak test without submergence for spontaneous pneumothorax.

    PubMed

    Uramoto, Hidetaka; Tanaka, Fumihiro

    2011-12-24

    Postoperative air leaks are frequent complications after surgery for a spontaneous pneumothorax (SP). We herein describe a new method to test for air leaks by using a transparent film and thoracic tube in a closed system. Between 2005 and 2010, 35 patients underwent a novel method for evaluating air leaks without submergence, and their clinical records were retrospectively reviewed. The data on patient characteristics, surgical details, and perioperative outcomes were analyzed. The differences in the clinical background and intraoperative factors did not reach a statistically significant level between the new and classical methods. The incidence of recurrence was also equivalent to the standard method. However, the length of the operation and drainage periods were significantly shorter in patients evaluated using the new method than the conventional method. Further, no postoperative complications were observed in patients evaluated using the new method. This simple technique is satisfactorily effective and does not result in any complications.

  2. Modelling wastewater treatment in a submerged anaerobic membrane bioreactor.

    PubMed

    Spagni, Alessandro; Ferraris, Marco; Casu, Stefania

    2015-01-01

    Mathematical modelling has been widely applied to membrane bioreactor (MBRs) processes. However, to date, very few studies have reported on the application of the anaerobic digestion model N.1 (ADM1) to anaerobic membrane processes. The aim of this study was to evaluate the applicability of the ADM1 to a submerged anaerobic MBR (SAMBR) treating simulated industrial wastewater composed of cheese whey and sucrose. This study demonstrated that the biological processes involved in SAMBRs can be modelled by using the ADM1. Moreover, the results showed that very few modifications of the parameters describing the ADM1 were required to reasonably fit the experimental data. In particular, adaptation to the specific conditions of the coefficients describing the wastewater characterisation and the reduction of the hydrolysis rate of particulate carbohydrate (khyd,ch) from 0.25 d(-1) (as suggested by the ADM1 for high-rate mesophilic reactors) to 0.13 d(-1) were required to fit the experimental data.

  3. Review of microfluidic microbioreactor technology for high-throughput submerged microbiological cultivation

    PubMed Central

    Hegab, Hanaa M.; ElMekawy, Ahmed; Stakenborg, Tim

    2013-01-01

    Microbial fermentation process development is pursuing a high production yield. This requires a high throughput screening and optimization of the microbial strains, which is nowadays commonly achieved by applying slow and labor-intensive submerged cultivation in shake flasks or microtiter plates. These methods are also limited towards end-point measurements, low analytical data output, and control over the fermentation process. These drawbacks could be overcome by means of scaled-down microfluidic microbioreactors (μBR) that allow for online control over cultivation data and automation, hence reducing cost and time. This review goes beyond previous work not only by providing a detailed update on the current μBR fabrication techniques but also the operation and control of μBRs is compared to large scale fermentation reactors. PMID:24404006

  4. 78 FR 47748 - Right-of-Way Grant of Submerged Lands on the Outer Continental Shelf to Support Renewable Energy...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-06

    ...-Way Grant of Submerged Lands on the Outer Continental Shelf to Support Renewable Energy Development... will use Form 0009 to issue a renewable energy right-of- way (ROW) grant on the Outer Continental Shelf....gov/Renewable-Energy Program/ Regulatory-Information/Index.aspx. DATES: The ROW grant form will be...

  5. Stimulating the biosynthesis of antroquinonol by addition of effectors and soybean oil in submerged fermentation of Antrodia camphorata.

    PubMed

    Hu, Yong-Dan; Lu, Rui-Qiu; Liao, Xiang-Ru; Zhang, Bo-Bo; Xu, Gan-Rong

    2016-05-01

    Antrodia camphorata is a precious medicinal mushroom that has attracted increasing attentions. Antroquinonol has been considered as being among the most biologically active components of A. camphorata. However, it was hardly biosynthesized via conventional submerged fermentation. Two approaches were applied to stimulate the biosynthesis of antroquinonol in submerged fermentation. On one hand, different kinds of effectors that may involve in the antroquinonol biosynthesis were investigated. Among the tested effectors, camphorwood leach liquor was the most effective for stimulating the antroquinonol production. On the other hand, because of the hydrophobic characteristics of antroquinonol, soybean oil was added to establish an extractive fermentation system for alleviating the product inhibition and resulting in enhanced productivity. The highest antroquinonol concentration could be achieved at 89.06 ± 0.14 mg/L when 10% (v/v) soybean oil was added at the beginning of the fermentation. This study will be of great significance for the study of A. camphorata and the bioprocess regulation of antroquinonol production. © 2015 International Union of Biochemistry and Molecular Biology, Inc.

  6. Direct measurements of lift and drag on shallowly submerged cobbles in steep streams: Implications for flow resistance and sediment transport

    NASA Astrophysics Data System (ADS)

    Lamb, Michael P.; Brun, Fanny; Fuller, Brian M.

    2017-09-01

    Steep mountain streams have higher resistance to flow and lower sediment transport rates than expected by comparison with low gradient rivers, and often these differences are attributed to reduced near-bed flow velocities and stresses associated with form drag on channel forms and immobile boulders. However, few studies have directly measured drag and lift forces acting on bed sediment for shallow flows over coarse sediment, which ultimately control sediment transport rates and grain-scale flow resistance. Here we report on particle lift and drag force measurements in flume experiments using a planar, fixed cobble bed over a wide range of channel slopes (0.004 < S < 0.3) and water discharges. Drag coefficients are similar to previous findings for submerged particles (CD ˜ 0.7) but increase significantly for partially submerged particles. In contrast, lift coefficients decrease from near unity to zero as the flow shallows and are strongly negative for partially submerged particles, indicating a downward force that pulls particles toward the bed. Fluctuating forces in lift and drag decrease with increasing relative roughness, and they scale with the depth-averaged velocity squared rather than the bed shear stress. We find that, even in the absence of complex bed topography, shallow flows over coarse sediment are characterized by high flow resistance because of grain drag within a roughness layer that occupies a significant fraction of the total flow depth, and by heightened critical Shields numbers and reduced sediment fluxes because of reduced lift forces and reduced turbulent fluctuations.

  7. Landcover Classification Using Deep Fully Convolutional Neural Networks

    NASA Astrophysics Data System (ADS)

    Wang, J.; Li, X.; Zhou, S.; Tang, J.

    2017-12-01

    Land cover classification has always been an essential application in remote sensing. Certain image features are needed for land cover classification whether it is based on pixel or object-based methods. Different from other machine learning methods, deep learning model not only extracts useful information from multiple bands/attributes, but also learns spatial characteristics. In recent years, deep learning methods have been developed rapidly and widely applied in image recognition, semantic understanding, and other application domains. However, there are limited studies applying deep learning methods in land cover classification. In this research, we used fully convolutional networks (FCN) as the deep learning model to classify land covers. The National Land Cover Database (NLCD) within the state of Kansas was used as training dataset and Landsat images were classified using the trained FCN model. We also applied an image segmentation method to improve the original results from the FCN model. In addition, the pros and cons between deep learning and several machine learning methods were compared and explored. Our research indicates: (1) FCN is an effective classification model with an overall accuracy of 75%; (2) image segmentation improves the classification results with better match of spatial patterns; (3) FCN has an excellent ability of learning which can attains higher accuracy and better spatial patterns compared with several machine learning methods.

  8. The relationship between critical flux and fibre movement induced by bubbling in a submerged hollow fibre system.

    PubMed

    Wicaksana, F; Fan, A G; Chen, V

    2005-01-01

    Bubbling has been used to enhance various processes. In this paper we deal with the effect of bubbling on submerged hollow fibre membranes, where bubbling is applied to prevent severe membrane fouling. Previous work with submerged hollow fibres has observed that significant fibre movement can be induced by bubbling and that there is a qualitative relationship between fibre movement and filtration performance. Therefore, the aim of the present research has been to analyse the link between bubbling, fibre movement and critical flux, identified as the flux at which the transmembrane pressure (TMP) starts to rise. Tests were performed on vertical isolated fibres with a model feed of yeast suspension. The fibres were subject to steady bubbling from below. The parameters of interest were the fibre characteristics, such as tightness, diameter and length, as well as feed concentration. The results confirmed that the critical fluxes are affected by the fibre characteristics and feed concentration. Higher critical flux values can be achieved by using loose fibres, smaller diameters and longer fibres. The enhancement is partially linked to fibre movement and this is confirmed by improved performance when fibres are subject to mechanical movement in the absence of bubbling.

  9. Bioprocessing of wheat bran for the production of lignocellulolytic enzyme cocktail by Cotylidia pannosa under submerged conditions.

    PubMed

    Sharma, Deepika; Garlapat, Vijay Kumar; Goel, Gunjan

    2016-04-02

    Characterization and production of efficient lignocellulytic enzyme cocktails for biomass conversion is the need for biofuel industry. The present investigation reports the modeling and optimization studies of lignocellulolytic enzyme cocktail production by Cotylidia pannosa under submerged conditions. The predominant enzyme activities of cellulase, xylanase and laccase were produced in the cocktail through submerged conditions using wheat bran as a substrate. A central composite design approach was utilized to model the production process using temperature, pH, incubation time and agitation as input variables with the goal of optimizing the output variables namely cellulase, xylanase and laccase activities. The effect of individual, square and interaction terms on cellulase, xylanase and laccase activities were depicted through the non-linear regression equations with significant R(2) and P-values. An optimized value of 20 U/ml, 17 U/ml and 13 U/ml of cellulase, xylanase and laccase activities, respectively, were obtained with a media pH of 5.0 in 77 h at 31C, 140 rpm using wheatbran as a substrate. Overall, the present study introduces a fungal strain, capable of producing lignocellulolytic enzyme cocktail for subsequent applications in biofuel industry.

  10. Bioprocessing of wheat bran for the production of lignocellulolytic enzyme cocktail by Cotylidia pannosa under submerged conditions

    PubMed Central

    Sharma, Deepika; Garlapat, Vijay Kumar; Goel, Gunjan

    2016-01-01

    ABSTRACT Characterization and production of efficient lignocellulytic enzyme cocktails for biomass conversion is the need for biofuel industry. The present investigation reports the modeling and optimization studies of lignocellulolytic enzyme cocktail production by Cotylidia pannosa under submerged conditions. The predominant enzyme activities of cellulase, xylanase and laccase were produced in the cocktail through submerged conditions using wheat bran as a substrate. A central composite design approach was utilized to model the production process using temperature, pH, incubation time and agitation as input variables with the goal of optimizing the output variables namely cellulase, xylanase and laccase activities. The effect of individual, square and interaction terms on cellulase, xylanase and laccase activities were depicted through the non-linear regression equations with significant R2 and P-values. An optimized value of 20 U/ml, 17 U/ml and 13 U/ml of cellulase, xylanase and laccase activities, respectively, were obtained with a media pH of 5.0 in 77 h at 31C, 140 rpm using wheatbran as a substrate. Overall, the present study introduces a fungal strain, capable of producing lignocellulolytic enzyme cocktail for subsequent applications in biofuel industry. PMID:26941214

  11. Quantitative determination of steroids in the fruiting bodies and submerged-cultured mycelia of Inonotus obliquus.

    PubMed

    Gao, Yuan; Xu, Hongyu; Lu, Zhenming; Xu, Zhenghong

    2009-11-01

    This study describes the method of quantitative determination of betulin, ergosterol, cholesterol, lanosterol, stigmasterol and sitosterol in the fruiting bodies and submerged-cultured mycelia of Inonotus obliquus. A high performance liquid chromatographic (HPLC) method was applied to separate these steroids. The procedure was carried out on a reversed-phase C, column, using a stepwise gradient of water-methanol as mobile phase with the following profile: 0-10 min, 10% water, 90% methanol; 10-40 min, 3% water, 97% methanol. The flow rate was 1.4 mL/min and the detection wavelength was 202 nm. The analysis was completed within 40 min. The results showed that this method has good reproducibility and satisfactory recoveries for the determination of steroids. The relative standard deviations of the peak areas were less than 2.94% (n = 5) for intraday assays. A good linear correlation was obtained in a range of 0.4-4.8 microg. The recoveries of betulin, ergosterol, cholesterol, lanosterol, stigmasterol, and sitosterol were 100.05%-100.72%, 99.31%-101.04%, 97.52%-101.63%, 96.61%-100.08%, 96.21%-100.76% and 100.04%-100.51%, respectively. This method can be applied to evaluate real samples, and it is rapid, accurate and suitable for the quantitative determination of steroids in the fruiting bodies and submerged-cultured mycelia of Inonotus obliquus.

  12. Marginal bone loss around non-submerged implants is associated with salivary microbiome during bone healing.

    PubMed

    Duan, Xiao-Bo; Wu, Ting-Xi; Guo, Yu-Chen; Zhou, Xue-Dong; Lei, Yi-Ling; Xu, Xin; Mo, An-Chun; Wang, Yong-Yue; Yuan, Quan

    2017-06-01

    Marginal bone loss during bone healing exists around non-submerged dental implants. The aim of this study was to identify the relationship between different degrees of marginal bone loss during bone healing and the salivary microbiome. One hundred patients were recruited, and marginal bone loss around their implants was measured using cone beam computed tomography during a 3-month healing period. The patients were divided into three groups according to the severity of marginal bone loss. Saliva samples were collected from all subjected and were analysed using 16S MiSeq sequencing. Although the overall structure of the microbial community was not dramatically altered, the relative abundance of several taxonomic groups noticeably changed. The abundance of species in the phyla Spirochaeta and Synergistetes increased significantly as the bone loss became more severe. Species within the genus Treponema also exhibited increased abundance, whereas Veillonella, Haemophilus and Leptotrichia exhibited reduced abundances, in groups with more bone loss. Porphyromonasgingivalis, Treponemadenticola and Streptococcus intermedius were significantly more abundant in the moderate group and/or severe group. The severity of marginal bone loss around the non-submerged implant was associated with dissimilar taxonomic compositions. An increased severity of marginal bone loss was related to increased proportions of periodontal pathogenic species. These data suggest a potential role of microbes in the progression of marginal bone loss during bone healing.

  13. Comparative study on the treatment of raw and biologically treated textile effluents through submerged nanofiltration.

    PubMed

    Chen, Qing; Yang, Ying; Zhou, Mengsi; Liu, Meihong; Yu, Sanchuan; Gao, Congjie

    2015-03-02

    Raw and biologically treated textile effluents were submerged filtrated using lab-fabricated hollow fiber nanofiltration membrane with a molecular weight cut-off of about 650 g/mol. Permeate flux, chemical oxygen demand (COD) reduction, color removal, membrane fouling, and cleaning were investigated and compared by varying the trans-membrane pressure (TMP) and volume concentrating factor (VCF). It was found that both raw and biologically treated textile effluents could be efficiently treated through submerged nanofiltration. The increase of TMP resulted in a decline in water permeability, COD reduction, color removal, and flux recovery ratio, while the increase of VCF resulted in both increased COD reduction and color removal. Under the TMP of 0.4 bar and VCF of 5.0, fluxes of 1.96 and 2.59 l/m(2)h, COD reductions of 95.7 and 94.2%, color removals of 99.0, and 97.3% and flux recovery ratios of 91.1 and 92.9% could be obtained in filtration of raw and biologically treated effluents, respectively. After filtration, the COD and color contents of the raw effluent declined sharply from 1780 to 325 mg/l and 1.200 to 0.060 Abs/cm, respectively, while for the biologically treated effluent, they decreased from 780 to 180 mg/l and 0.370 to 0.045 Abs/cm, respectively. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Geologic evolution of the Bering Sea Komandorksy deep basin

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bogdanov, N.A.

    1986-07-01

    The deep-water Komandorsky basin is located in the southwestern part of the Bering Sea. On the east, it is separated from the Aleutian basin by the submerged Shirshov Ridge; on the west, it is bordered by structures of the north Kamchatka accretionary prism. The Komandorsky basin is characterized by strongly dissected relief of it acoustic basement, which is overlain by a 1.5 to 2.0-km thick sedimentary cover. The western part of the basin is occupied by a rift zone, which is characterized by modern seismicity and high heat flow. It is considered to be the axial zone of Miocene-Pleistocene spreading.more » On the north terrace of the Komandorsky island arc, traced active volcanos provide evidence that subduction is occurring under the arc from the north. The spreading rift zone is reflected on the continent in Miocene-Pleistocene volcanic rocks, characterized by typical oceanic tholeiitic composition. The Komandorsky basin formed as a result of spreading during the Maestrichtian. Spreading within the basin occurred during the early and middle Oligocene and the late Miocene. East and west of the spreading axis, accretionary prisms formed. The latter are observed along the western flank of the Shirshov Ridge and on the eastern sides of the Kamchatka Peninsula and Koraginsky Island.« less

  15. Optimization design of submerged propeller in oxidation ditch by computational fluid dynamics and comparison with experiments.

    PubMed

    Zhang, Yuquan; Zheng, Yuan; Fernandez-Rodriguez, E; Yang, Chunxia; Zhu, Yantao; Liu, Huiwen; Jiang, Hao

    The operating condition of a submerged propeller has a significant impact on flow field and energy consumption of the oxidation ditch. An experimentally validated numerical model, based on the computational fluid dynamics (CFD) tool, is presented to optimize the operating condition by considering two important factors: flow field and energy consumption. Performance demonstration and comparison of different operating conditions were carried out in a Carrousel oxidation ditch at the Yingtang wastewater treatment plants in Anhui Province, China. By adjusting the position and rotating speed together with the number of submerged propellers, problems of sludge deposit and the low velocity in the bend could be solved in a most cost-effective way. The simulated results were acceptable compared with the experimental data and the following results were obtained. The CFD model characterized flow pattern and energy consumption in the full-scale oxidation ditch. The predicted flow field values were within -1.28 ± 7.14% difference from the measured values. By determining three sets of propellers under the rotating speed of 6.50 rad/s with one located 5 m from the first curved wall, after numerical simulation and actual measurement, not only the least power density but also the requirement of the flow pattern could be realized.

  16. Numerical study on the effect of a lobed nozzle on the flow characteristics of submerged exhaust

    NASA Astrophysics Data System (ADS)

    Miao, T. C.; Du, T.; Wu, D. Z.; Wang, L. Q.

    2016-05-01

    In order to investigate the effecting mechanism of nozzle structure on the flow characteristics of submerged exhaust, the processes of air exhausted from a lobed nozzle and a round nozzle into water have been numerically simulated using realizable k - ɛ model under the framework of the volume of fluid (VOF) model. Both the flow structure and the upstream pressure fluctuations are taken into consideration. The calculated results are in good agreement with the experimental results, showing that gas exhausted from the lobed nozzle would flow along the axial direction easier. Flow structure of the gas exhausted from the lobed nozzle is more continuous and smoother. The pressure fluctuations in the upstream pipeline would also be reduced when gas exhausted from the lobed nozzle. The resulting analysis indicates that the lobed structure could deflect water flow into the gas jet. The induced water would be mixed into the gas jet in form of small droplets, making the jet more continuous. As a result, the mixed jet flow would be less obstructed by the surrounding water, and the upstream pressure fluctuation would be reduced. The work in this paper partly explained the effecting mechanism of nozzle structure on the flow characteristics of submerged exhaust. The results are useful in the designing of exhaust nozzles.

  17. Wastewater treatment with submerged fixed bed biofilm reactor systems--design rules, operating experiences and ongoing developments.

    PubMed

    Schlegel, S; Koeser, H

    2007-01-01

    Wastewater treatment systems using bio-films that grow attached to a support media are an alternative to the widely used suspended growth activated sludge process. Different fixed growth biofilm reactors are commercially used for the treatment of municipal as well as industrial wastewater. In this paper a fairly new fixed growth biofilm system, the submerged fixed bed biofilm reactor (SFBBR), is discussed. SFBBRs are based on aerated submerged fixed open structured plastic media for the support of the biofilm. They are generally operated without sludge recirculation in order to avoid clogging of the support media and problems with the control of the biofilm. Reactor and process design considerations for these reactors are reviewed. Measures to ensure the development and maintenance of an active biofilm are examined. SFBBRs have been applied successfully to small wastewater treatment plants where complete nitrification but no high degree of denitrification is necessary. For the pre-treatment of industrial wastewater the use of SFBBRs is advantageous, especially in cases of wastewater with high organic loading or high content of compounds with low biodegradability. Performance data from exemplary commercial plants are given. Ongoing research and development efforts aim at achieving a high simultaneous total nitrogen (TN) removal of aerated SFBBRs and at improving the efficiency of TN removal in anoxic SFBBRs.

  18. Study on mechanical and microstructure behavior of submerged arc welding flux using red mud

    NASA Astrophysics Data System (ADS)

    Dewangan, Rishi; Pandey, Pankaj K.; Upadhyay, Renu

    2018-05-01

    This paper emphasis on utilization of Red Mud for preparing submerged arc welding flux and study its mechanical and microstructure behavior. Among the six fluxes prepared in the laboratory, Flux no. 1 (basicity 1.106) found to be best due to its running performance, micro hardness and Brinell hardness. The hardness value (HV) of the fluxes was varying from 165.70 to 217.15 at a load of 1000gm respectively. From the micrograph of welded metal, acicular ferrite found to be optimum which helps in increasing the ductility and hardness of the welded material.

  19. 77 FR 52353 - Right-of-Way Grant of Submerged Lands on the Outer Continental Shelf to Support Renewable Energy...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-29

    ... of Submerged Lands on the Outer Continental Shelf to Support Renewable Energy Development AGENCY... would be used to issue Outer Continental Shelf (OCS) renewable energy right-of-way (ROW) grants in order... renewable energy, but does not constitute a project easement. The ability of an ROW grantee to install such...

  20. Modification of Surf Zone Turbulence and the Undertow by a Submerged Canopy

    NASA Astrophysics Data System (ADS)

    Mandel, T.; Koseff, J. R.; Rosenzweig, I.; Suckale, J.; Zarama, F. J.

    2016-02-01

    As sea level rise and stronger storm events threaten our coastlines, coastal vegetation has come under consideration as a potentially resilient, financially viable tool to mitigate flooding and erosion. However, the actual role of this "green infrastructure" in the near-shore region is not fully understood. In order to evaluate the role of vegetation in coastal protection, a series of experiments were conducted in a simulated laboratory surf zone. We examine the impact of canopy location and submergence on the undertow profile, turbulent kinetic energy, and Reynolds stress for varying Reynolds number and Keulegan-Carpenter number, and compare these results to theoretical formulations that utilize a depth-averaged undertow and highly simplified eddy viscosity.

  1. Energetics of acclimation to NaCl by submerged, anoxic rice seedlings

    PubMed Central

    Kurniasih, Budiastuti; Greenway, Hank; Colmer, Timothy David

    2017-01-01

    Background and aims Our aim was to elucidate how plant tissues under a severe energy crisis cope with imposition of high NaCl, which greatly increases ion fluxes and hence energy demands. The energy requirements for ion regulation during combined salinity and anoxia were assessed to gain insights into ion transport processes in the anoxia-tolerant coleoptile of rice. Methods We studied the combined effects of anoxia plus 50 or 100 mm NaCl on tissue ions and growth of submerged rice (Oryza sativa) seedlings. Excised coleoptiles allowed measurements in aerated or anoxic conditions of ion net fluxes and O2 consumption or ethanol formation and by inference energy production. Key Results Over 80 h of anoxia, coleoptiles of submerged intact seedlings grew at 100 mm NaCl, but excised coleoptiles, with 50 mm exogenous glucose, survived only at 50 mm NaCl, possibly due to lower energy production with glucose than for intact coleoptiles with sucrose as substrate. Rates of net uptake of Na+ and Cl− by coleoptiles in anoxia were about half those in aerated solution. Ethanol formation in anoxia and O2 uptake in aerobic solution were each increased by 13–15 % at 50 mm NaCl, i.e. ATP formation was stimulated. For acclimation to 50 mm NaCl, the anoxic tissues used only 25 % of the energy that was expended by aerobic tissues. Following return of coleoptiles to aerated non-saline solution, rates of net K+ uptake recovered to those in continuously aerated solution, demonstrating there was little injury during anoxia with 50 mm NaCl. Conclusion Rice seedlings survive anoxia, without the coleoptile incurring significant injury, even with the additional energy demands imposed by NaCl (100 mm when intact, 50 mm when excised). Energy savings were achieved in saline anoxia by less coleoptile growth, reduced ion fluxes as compared to aerobic coleoptiles and apparent energy-economic ion transport systems. PMID:27694332

  2. Silica nanoparticles are less toxic to human lung cells when deposited at the air–liquid interface compared to conventional submerged exposure

    PubMed Central

    Saathoff, Harald; Leisner, Thomas; Al-Rawi, Marco; Simon, Michael; Seemann, Gunnar; Dössel, Olaf; Mülhopt, Sonja; Paur, Hanns-Rudolf; Fritsch-Decker, Susanne

    2014-01-01

    Summary Background: Investigations on adverse biological effects of nanoparticles (NPs) in the lung by in vitro studies are usually performed under submerged conditions where NPs are suspended in cell culture media. However, the behaviour of nanoparticles such as agglomeration and sedimentation in such complex suspensions is difficult to control and hence the deposited cellular dose often remains unknown. Moreover, the cellular responses to NPs under submerged culture conditions might differ from those observed at physiological settings at the air–liquid interface. Results: In order to avoid problems because of an altered behaviour of the nanoparticles in cell culture medium and to mimic a more realistic situation relevant for inhalation, human A549 lung epithelial cells were exposed to aerosols at the air–liquid interphase (ALI) by using the ALI deposition apparatus (ALIDA). The application of an electrostatic field allowed for particle deposition efficiencies that were higher by a factor of more than 20 compared to the unmodified VITROCELL deposition system. We studied two different amorphous silica nanoparticles (particles produced by flame synthesis and particles produced in suspension by the Stöber method). Aerosols with well-defined particle sizes and concentrations were generated by using a commercial electrospray generator or an atomizer. Only the electrospray method allowed for the generation of an aerosol containing monodisperse NPs. However, the deposited mass and surface dose of the particles was too low to induce cellular responses. Therefore, we generated the aerosol with an atomizer which supplied agglomerates and thus allowed a particle deposition with a three orders of magnitude higher mass and of surface doses on lung cells that induced significant biological effects. The deposited dose was estimated and independently validated by measurements using either transmission electron microscopy or, in case of labelled NPs, by fluorescence analyses

  3. Comparison of submerged and unsubmerged printing of ovarian cancer cells.

    PubMed

    Davidoff, Sherry N; Au, David; Smith, Samuel; Brooks, Amanda E; Brooks, Benjamin D

    2015-01-01

    A high-throughput cell based assay would greatly aid in the development and screening of ovarian cancer drug candidates. Previously, a three-dimensional microfluidic printer that is not only capable of controlling the location of cell deposition, but also of maintaining a liquid, nutrient rich environment to preserve cellular phenotype has been developed (Wasatch Microfluidics). In this study, we investigated the impact (i.e., viability, density, and phenotype) of depositing cells on a surface submerged in cell culture media. It was determined that submersion of the microfluidic print head in cell media did not alter the cell density, viability, or phenotype.. This article describes an in depth study detailing the impact of one of the fundamental components of a 3D microfluidic cell printer designed to mimic the in vivo cell environment. Development of such a tool holds promise as a high-throughput drug-screening platform for new cancer therapeutics.

  4. Development of a TL-3 deep beam tubular backup bridge rail.

    DOT National Transportation Integrated Search

    2010-12-01

    The objective of this study is to investigate the performance of the Ohio Department of Transportation (ODOT) Deep Beam bridge rail system per the National Cooperative Highway Research Program (NCHRP) Report 350 TL-3. Analytical study, computer simul...

  5. Cell wall α-1,3-glucan prevents α-amylase adsorption onto fungal cell in submerged culture of Aspergillus oryzae.

    PubMed

    Zhang, Silai; Sato, Hiroki; Ichinose, Sakurako; Tanaka, Mizuki; Miyazawa, Ken; Yoshimi, Akira; Abe, Keietsu; Shintani, Takahiro; Gomi, Katsuya

    2017-07-01

    We have previously reported that α-amylase (Taka-amylase A, TAA) activity disappears in the later stage of submerged Aspergillus oryzae culture as a result of TAA adsorption onto the cell wall. Chitin, one of the major components of the cell wall, was identified as a potential factor that facilitates TAA adsorption. However, TAA adsorption only occurred in the later stage of cultivation, although chitin was assumed to be sufficiently abundant in the cell wall regardless of the submerged culture period. This suggested the presence a factor that inhibits TAA adsorption to the cell wall in the early stage of cultivation. In the current study, we identified α-1,3-glucan as a potential inhibiting factor for TAA adsorption. We constructed single, double, and triple disruption mutants of three α-1,3-glucan synthase genes (agsA, agsB, and agsC) in A. oryzae. Growth characteristics and cell wall component analysis of these disruption strains showed that AgsB plays a major role in α-1,3-glucan synthesis. In the ΔagsB mutant, TAA was adsorbed onto the mycelium in all stages of cultivation (early and later), and the ΔagsB mutant cell walls had a significantly high capacity for TAA adsorption. Moreover, the α-1,3-glucan content of the cell wall prepared from the wild-type strain in the later stage of cultivation was markedly reduced compared with that in the early stage. These results suggest that α-1,3-glucan is a potential inhibiting factor for TAA adsorption onto the cell wall component, chitin, in the early stage of submerged culture in A. oryzae. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  6. 78 FR 59626 - Main Hawaiian Islands Deep 7 Bottomfish Annual Catch Limits and Accountability Measures for 2013-14

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-27

    ... Accountability Measures for 2013-14 AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and... associated accountability measure (AM) close the non-commercial and commercial fisheries for Deep 7...

  7. Response of Submerged Macrophyte Communities to External and Internal Restoration Measures in North Temperate Shallow Lakes.

    PubMed

    Hilt, Sabine; Alirangues Nuñez, Marta M; Bakker, Elisabeth S; Blindow, Irmgard; Davidson, Thomas A; Gillefalk, Mikael; Hansson, Lars-Anders; Janse, Jan H; Janssen, Annette B G; Jeppesen, Erik; Kabus, Timm; Kelly, Andrea; Köhler, Jan; Lauridsen, Torben L; Mooij, Wolf M; Noordhuis, Ruurd; Phillips, Geoff; Rücker, Jacqueline; Schuster, Hans-Heinrich; Søndergaard, Martin; Teurlincx, Sven; van de Weyer, Klaus; van Donk, Ellen; Waterstraat, Arno; Willby, Nigel; Sayer, Carl D

    2018-01-01

    Submerged macrophytes play a key role in north temperate shallow lakes by stabilizing clear-water conditions. Eutrophication has resulted in macrophyte loss and shifts to turbid conditions in many lakes. Considerable efforts have been devoted to shallow lake restoration in many countries, but long-term success depends on a stable recovery of submerged macrophytes. However, recovery patterns vary widely and remain to be fully understood. We hypothesize that reduced external nutrient loading leads to an intermediate recovery state with clear spring and turbid summer conditions similar to the pattern described for eutrophication. In contrast, lake internal restoration measures can result in transient clear-water conditions both in spring and summer and reversals to turbid conditions. Furthermore, we hypothesize that these contrasting restoration measures result in different macrophyte species composition, with added implications for seasonal dynamics due to differences in plant traits. To test these hypotheses, we analyzed data on water quality and submerged macrophytes from 49 north temperate shallow lakes that were in a turbid state and subjected to restoration measures. To study the dynamics of macrophytes during nutrient load reduction, we adapted the ecosystem model PCLake. Our survey and model simulations revealed the existence of an intermediate recovery state upon reduced external nutrient loading, characterized by spring clear-water phases and turbid summers, whereas internal lake restoration measures often resulted in clear-water conditions in spring and summer with returns to turbid conditions after some years. External and internal lake restoration measures resulted in different macrophyte communities. The intermediate recovery state following reduced nutrient loading is characterized by a few macrophyte species (mainly pondweeds) that can resist wave action allowing survival in shallow areas, germinate early in spring, have energy-rich vegetative

  8. Response of Submerged Macrophyte Communities to External and Internal Restoration Measures in North Temperate Shallow Lakes

    PubMed Central

    Hilt, Sabine; Alirangues Nuñez, Marta M.; Bakker, Elisabeth S.; Blindow, Irmgard; Davidson, Thomas A.; Gillefalk, Mikael; Hansson, Lars-Anders; Janse, Jan H.; Janssen, Annette B. G.; Jeppesen, Erik; Kabus, Timm; Kelly, Andrea; Köhler, Jan; Lauridsen, Torben L.; Mooij, Wolf M.; Noordhuis, Ruurd; Phillips, Geoff; Rücker, Jacqueline; Schuster, Hans-Heinrich; Søndergaard, Martin; Teurlincx, Sven; van de Weyer, Klaus; van Donk, Ellen; Waterstraat, Arno; Willby, Nigel; Sayer, Carl D.

    2018-01-01

    Submerged macrophytes play a key role in north temperate shallow lakes by stabilizing clear-water conditions. Eutrophication has resulted in macrophyte loss and shifts to turbid conditions in many lakes. Considerable efforts have been devoted to shallow lake restoration in many countries, but long-term success depends on a stable recovery of submerged macrophytes. However, recovery patterns vary widely and remain to be fully understood. We hypothesize that reduced external nutrient loading leads to an intermediate recovery state with clear spring and turbid summer conditions similar to the pattern described for eutrophication. In contrast, lake internal restoration measures can result in transient clear-water conditions both in spring and summer and reversals to turbid conditions. Furthermore, we hypothesize that these contrasting restoration measures result in different macrophyte species composition, with added implications for seasonal dynamics due to differences in plant traits. To test these hypotheses, we analyzed data on water quality and submerged macrophytes from 49 north temperate shallow lakes that were in a turbid state and subjected to restoration measures. To study the dynamics of macrophytes during nutrient load reduction, we adapted the ecosystem model PCLake. Our survey and model simulations revealed the existence of an intermediate recovery state upon reduced external nutrient loading, characterized by spring clear-water phases and turbid summers, whereas internal lake restoration measures often resulted in clear-water conditions in spring and summer with returns to turbid conditions after some years. External and internal lake restoration measures resulted in different macrophyte communities. The intermediate recovery state following reduced nutrient loading is characterized by a few macrophyte species (mainly pondweeds) that can resist wave action allowing survival in shallow areas, germinate early in spring, have energy-rich vegetative

  9. Submerged fermentation of Lactobacillus rhamnosus YS9 for γ-aminobutyric acid (GABA) production

    PubMed Central

    Lin, Qian

    2013-01-01

    γ-Aminobutyric acid (GABA) is a major inhibitory neurotransmitter in central nervous system, and its application in drugs and functional foods has attracted great attention. To enhance production of γ-aminobutyric acid, Lactobacillus rhamnosus YS9, a strain isolated from Chinese traditional fermented food pickled vegetable, was grown under submerged fermentation. Its cultivation conditions were investigated. When culture pH condition was adjusted to the optimal pH of glutamate decarboxylase activity, culture of Lb. rhamnosus YS9 in medium supplemented with 200 mM of monosodium glutamate and 200 μM of pyridoxal phosphate (PLP), produced 187 mM of GABA. PMID:24159304

  10. Involvement of Physical Parameters in Medium Improvement for Tannase Production by Aspergillus niger FETL FT3 in Submerged Fermentation

    PubMed Central

    Darah, I.; Sumathi, G.; Jain, K.; Hong, Lim Sheh

    2011-01-01

    Aspergillus niger FETL FT3, a local extracellular tannase producer strain that was isolated from one of dumping sites of tannin-rich barks of Rhizophora apiculata in Perak, Malaysia. This fungus was cultivated in 250 mL Erlenmeyer flask under submerged fermentation system. Various physical parameters were studied in order to maximize the tannase production. Maximal yield of tannase production, that is, 2.81 U per mL was obtained on the fourth day of cultivation when the submerged fermentation was carried out using liquid Czapek-Dox medium containing (percent; weight per volume) 0.25% NaNO3, 0.1% KH2PO4, 0.05% MgSO4 ·7H2O, 0.05% KCl, and 1.0% tannic acid. The physical parameters used initial medium pH of 6.0, incubation temperature of 30°C, agitation speed of 200 rpm and inoculums size of 6 × 106 spores/ ml. This research has showed that physical parameters were influenced the tannase production by the fungus with 156.4 percent increment. PMID:21826273

  11. Involvement of Physical Parameters in Medium Improvement for Tannase Production by Aspergillus niger FETL FT3 in Submerged Fermentation.

    PubMed

    Darah, I; Sumathi, G; Jain, K; Hong, Lim Sheh

    2011-01-01

    Aspergillus niger FETL FT3, a local extracellular tannase producer strain that was isolated from one of dumping sites of tannin-rich barks of Rhizophora apiculata in Perak, Malaysia. This fungus was cultivated in 250 mL Erlenmeyer flask under submerged fermentation system. Various physical parameters were studied in order to maximize the tannase production. Maximal yield of tannase production, that is, 2.81 U per mL was obtained on the fourth day of cultivation when the submerged fermentation was carried out using liquid Czapek-Dox medium containing (percent; weight per volume) 0.25% NaNO(3), 0.1% KH(2)PO(4), 0.05% MgSO(4) ·7H(2)O, 0.05% KCl, and 1.0% tannic acid. The physical parameters used initial medium pH of 6.0, incubation temperature of 30°C, agitation speed of 200 rpm and inoculums size of 6 × 10(6) spores/ ml. This research has showed that physical parameters were influenced the tannase production by the fungus with 156.4 percent increment.

  12. Domestic wastewater treatment by a submerged MBR (membrane bio-reactor) with enhanced air sparging.

    PubMed

    Chang, I S; Judd, S J

    2003-01-01

    The air sparging technique has been recognised as an effective way to control membrane fouling. However, its application to a submerged MBR (Membrane Bio-Reactor) has not yet been reported. This paper deals with the performances of air sparging on a submerged MBR for wastewater treatment. Two kinds of air sparging techniques were used respectively. First, air is injected into the membrane tube channels so that mixed liquor can circulate in the bioreactor (air-lift mode). Second, a periodic air-jet into the membrane tube is introduced (air-jet mode). Their applicability was evaluated with a series of lab-scale experiments using domestic wastewater. The flux increased from 23 to 33 l m(-2) h(-1) (43% enhancement) when air was injected for the air-lift module. But further increase of flux was not observed as the gas flow increased. The Rc/(Rc+Rf), ratio of cake resistance (Rc) to sum of Rc and Rf (internal fouling resistance), was 23%, indicating that the Rc is not the predominant resistance unlike other MBR studies. It showed that the cake layer was removed sufficiently due to the air injection. Thus, an increase of airflow could not affect the flux performance. The air-jet module suffered from a clogging problem with accumulated sludge inside the lumen. Because the air-jet module has characteristics of dead end filtration, a periodic air-jet was not enough to blast all the accumulated sludge out. But flux was greater than in the air-lift module if the clogging was prevented by an appropriate cleaning regime such as periodical backwashing.

  13. Influence of nanoparticles on filterability of fruit-juice industry wastewater using submerged membrane bioreactor.

    PubMed

    Demirkol, Guler Turkoglu; Dizge, Nadir; Acar, Turkan Ormanci; Salmanli, Oyku Mutlu; Tufekci, Nese

    2017-07-01

    In this study, polyethersulfone (PES) ultrafiltration membrane surface was modified with nano-sized zinc oxide (nZnO) and silver (nAg) to improve the membrane filterability of the mixed liquor and used to treat fruit-juice industry wastewater in a submerged membrane bioreactor (MBR). The nAg was synthesized using three different methods. In the first method, named as nAg-M1, PES membrane was placed on the membrane module and nAg solution was passed through the membrane for 24 h at 25 ± 1 °C. In the second method, named as nAg-M2, PES membrane was placed in a glass container and it was shaken for 24 h at 150 rpm at 25 ± 1 °C. In the third method, named as nAg-M3, Ag nanoparticles were loaded onto PES membrane in L-ascorbic acid solution (0.1 mol/L) at pH 2 for 24 h at 150 rpm at 25 ± 1 °C. For the preparation of nZnO coated membrane, nZnO nanoparticles solution was passed through the membrane for 24 h at 25 ± 1 °C. Anti-fouling performance of pristine and coated membranes was examined using the submerged MBR. The results showed that nZnO and nAg-M3 membranes showed lower flux decline compared with pristine membrane. Moreover, pristine and coated PES membranes were characterized using a permeation test, contact angle goniometer, and scanning electron microscopy.

  14. Effect of inorganic nutrients on relative contributions of fungi and bacteria to carbon flow from submerged decomposing leaf litter

    Treesearch

    Vladislav Gulis; Keller Suberkropp

    2003-01-01

    The relative contributions of fungi and bacteria to carbon flow from submerged decaying plant litter at different levels of inorganic nutrients (N and P) were studied. We estimated leaf mass loss, fungal and bacterial biomass and production, and microbial respiration and constructed partial carbon budgets for red maple leaf disks precolonized in a stream and then...

  15. [National preparedness for biological mass casualty event: between the devil and the deep blue sea].

    PubMed

    Eldad, Arieh

    2002-05-01

    Species of plants and animals, as well as nations of human beings were extinguished throughout the prehistory and history of this planet. One of the possible explanations for this phenomenon is a large scale epidemic of viral, bacterial or fungal infections. One well-documented example was the smallpox epidemic among native Indians of South America following the European invasion. Deliberate dissemination of disease was used as a weapon during the Middle Ages when corpses of plague casualties were thrown over the walls and into the besieged towns. The Book of Kings II, of the Bible, in chapter 19 recalls the story of 185,000 soldiers of Sennacherib that died in one night, near the walls of Jerusalem. The possibility of causing mass casualty by dissemination of infectious disease has driven countries and terrorist organizations to produce and store large quantities of bacteria or viruses. The death of thousands in the USA on September 11, 2001, demonstrated that terror has no moral prohibitions, only technical limitations. Terror organizations will not hesitate to use weapons for mass destruction to kill many, and if only few will die, it will still serve the purpose of these evil organizations: to strew panic, to destroy normal life and to increase fear and instability. Any government that faces decisions about how to be better prepared against biological warfare is pushed between the devil and the deep blue sea. On the one hand: the better we will be prepared, equipped with antibiotics and vaccines--the more lives of casualties we will be able to save. Better public education will help to reduce the damage, but, on the other hand--in order to cause more people to make the effort to equip themselves or to refresh their protective kit--we will have to increase their level of concern. In order to improve the medical education of all members of the medical teams we will have to start a broad and intense campaign, thereby taking the risk of increasing stress in the

  16. Mathematical model for Trametes versicolor growth in submerged cultivation.

    PubMed

    Tisma, Marina; Sudar, Martina; Vasić-Racki, Durda; Zelić, Bruno

    2010-08-01

    Trametes versicolor is a white-rot fungus known as a producer of extracellular enzymes such as laccase, manganese-peroxidase, and lignin-peroxidase. The production of these enzymes requires detailed knowledge of the growth characteristics and physiology of the fungus. Submerged cultivations of T. versicolor on glucose, fructose, and sucrose as sole carbon sources were performed in shake flasks. Sucrose hydrolysis catalyzed by the whole cells of T. versicolor was considered as one-step enzymatic reaction described with Michaelis-Menten kinetics. Kinetic parameters of invertase-catalyzed sucrose hydrolysis were estimated (K (m) = 7.99 g dm(-3) and V (m) = 0.304 h(-1)). Monod model was used for description of kinetics of T. versicolor growth on glucose and fructose as sole carbon sources. Growth associated model parameters were estimated from the experimental results obtained by independent experiments (mu(G)(max) = 0.14 h(-1), K(G)(S) = 8.06 g dm(-3), mu(F)(max) = 0.37 h(-1) and K(F)(S) = 54.8 g dm(-3)). Developed mathematical model is in good agreement with the experimental results.

  17. Investigation of micro burner performance during porous media combustion for surface and submerged flames

    NASA Astrophysics Data System (ADS)

    Janvekar, Ayub Ahmed; Abdullah, M. Z.; Ahmad, Z. A.; Abas, Aizat; Hussien, Ahmed A.; Kataraki, Pramod S.; Mohamed, Mazlan; Husin, Azmi; Fadzli, Khairil

    2018-05-01

    Porous media combustion is considered to be one of the popular choice due to its tremendous advantages. Such type of combustion liberates not only super stable flame but also maintains emissions parameters below thresholds level. Present study incorporates reaction and preheat layer with discrete and foam type of materials respectively. Burner was made to run in ultra-lean mode. Optimum equivalence ratio was found out to be 0.7 for surface flame, while 0.6 during submerged flame condition. Maximum thermal efficiency was noted to be 81%. Finally, emissions parameters where recorded continuously to measure NOx and CO, which were under global limits.

  18. Sustainable operation of submerged Anammox membrane bioreactor with recycling biogas sparging for alleviating membrane fouling.

    PubMed

    Li, Ziyin; Xu, Xindi; Xu, Xiaochen; Yang, FengLin; Zhang, ShuShen

    2015-12-01

    A submerged anaerobic ammonium oxidizing (Anammox) membrane bioreactor with recycling biogas sparging for alleviating membrane fouling has been successfully operated for 100d. Based on the batch tests, a recycling biogas sparging rate at 0.2m(3)h(-1) was fixed as an ultimate value for the sustainable operation. The mixed liquor volatile suspended solid (VSS) of the inoculum for the long operation was around 3000mgL(-1). With recycling biogas sparging rate increasing stepwise from 0 to 0.2m(3)h(-1), the reactor reached an influent total nitrogen (TN) up to 1.7gL(-1), a stable TN removal efficiency of 83% and a maximum specific Anammox activity (SAA) of 0.56kg TNkg(-1) VSSd(-1). With recycling biogas sparging rate at 0.2 m(3) h(-1) (corresponding to an aeration intensity of 118m(3)m(-2)h(-1)), the membrane operation circle could prolong by around 20 times compared to that without gas sparging. Furthermore, mechanism of membrane fouling was proposed. And with recycling biogas sparging, the VSS and EPS content increasing rate in cake layer were far less than the ones without biogas sparging. The TN removal performance and sustainable membrane operation of this system showed the appealing potential of the submerged Anammox MBR with recycling biogas sparging in treating high-strength nitrogen-containing wastewaters. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Observation of pressure variation in the cavitation region of submerged journal bearings

    NASA Technical Reports Server (NTRS)

    Etsion, I.; Ludwig, L. P.

    1981-01-01

    Visual observations and pressure measurements in the cavitation zone of a submerged journal bearing are described. Tests are run at speeds of 1840 and 3000 rpm, and at each speed, four different levels of the ambient supply pressure are applied, ranging from 13.6 KPa to 54.4 KPa. A strong reverse flow is detected inside the cavitation area adjacent to its downstream end, and significant pressure variations on the order of 50 KPa are found inside the cavitation region at the downstream portion of its circumferential extent. Results indicate that the assumption of a constant cavitation pressure is incorrect in the case of enclosed cavitations, and it is postulated that oil which is saturated with air under atmospheric pressure becomes oversaturated in the subcavity pressure loop.

  20. Does the Deep Layer of the Deep Temporalis Fascia Really Exist?

    PubMed

    Li, Hui; Li, Kaide; Jia, Wenhao; Han, Chaoying; Chen, Jinlong; Liu, Lei

    2018-04-14

    It has been widely accepted that a split of the deep temporal fascia occurs approximately 2 to 3 cm above the zygomatic arch and extends into the superficial and deep layers. The deep layer of the deep temporal fascia is between the superficial temporal fat pad and the temporal muscle. However, during procedures, the authors noted the absence of the deep layer of the deep temporal fascia between the superficial temporal fat pad and the temporal muscle. This prospective study was conducted to clarify the presence or absence of a deep layer of the deep temporal fascia. Anatomic layers of the soft tissues of the temporal region, with reference to the deep temporal fascia, were investigated in 130 cases operated on for zygomaticofacial fractures using the supratemporal approach from June 2013 to June 2017. Of 130 surgeries, the authors found the absence of a thick, obviously identifiable, fascial layer between the superficial temporal fat pad and the temporal muscle. In fact, the authors found nothing above the temporal muscle in most cases. In a few cases, the authors observed only a small amount of scattered loose connective tissue between the superficial temporal fat pad and the temporal muscle. This clinical study showed the absence of a thick, obviously identifiable, fascial layer between the superficial temporal fat pad and the temporal muscle, which suggests that a "deep layer of the deep temporal fascia" might not exist. Copyright © 2018. Published by Elsevier Inc.

  1. Production of Trametes pubescens laccase under submerged and semi-solid culture conditions on agro-industrial wastes.

    PubMed

    Gonzalez, Juan C; Medina, Sandra C; Rodriguez, Alexander; Osma, Johann F; Alméciga-Díaz, Carlos J; Sánchez, Oscar F

    2013-01-01

    Laccases are copper-containing enzymes involved in the degradation of lignocellulosic materials and used in the treatment of phenol-containing wastewater. In this study we investigated the effect of culture conditions, i.e. submerged or semi-solid, and copper supplementation on laccase production by Trametespubescens grown on coffee husk, soybean pod husk, or cedar sawdust. The highest specific laccase activity was achieved when the culture was conducted under submerged conditions supplemented with copper (5 mM), and using coffee husk as substrate. The crude extracts presented two laccase isoforms with molecular mass of 120 (Lac1) and 60 kDa (Lac2). Regardless of the substrate, enzymatic crude extract and purified fractions behaved similarly at different temperatures and pHs, most of them presented the maximum activity at 55 °C and a pH range between 2 and 3. In addition, they showed similar stability and electro-chemical properties. At optimal culture conditions laccase activity was 7.69 ± 0.28 U mg(-1) of protein for the crude extract, and 0.08 ± 0.001 and 2.86 ± 0.05 U mg(-1) of protein for Lac1 and Lac2, respectively. In summary, these results show the potential of coffee husk as an important and economical growth medium to produce laccase, offering a new alternative use for this common agro-industrial byproduct.

  2. Production of Trametes pubescens Laccase under Submerged and Semi-Solid Culture Conditions on Agro-Industrial Wastes

    PubMed Central

    Rodriguez, Alexander; Osma, Johann F.; Alméciga-Díaz, Carlos J.; Sánchez, Oscar F.

    2013-01-01

    Laccases are copper-containing enzymes involved in the degradation of lignocellulosic materials and used in the treatment of phenol-containing wastewater. In this study we investigated the effect of culture conditions, i.e. submerged or semi-solid, and copper supplementation on laccase production by Trametes pubescens grown on coffee husk, soybean pod husk, or cedar sawdust. The highest specific laccase activity was achieved when the culture was conducted under submerged conditions supplemented with copper (5 mM), and using coffee husk as substrate. The crude extracts presented two laccase isoforms with molecular mass of 120 (Lac1) and 60 kDa (Lac2). Regardless of the substrate, enzymatic crude extract and purified fractions behaved similarly at different temperatures and pHs, most of them presented the maximum activity at 55 °C and a pH range between 2 and 3. In addition, they showed similar stability and electro-chemical properties. At optimal culture conditions laccase activity was 7.69±0.28 U mg-1 of protein for the crude extract, and 0.08±0.001 and 2.86±0.05 U mg-1 of protein for Lac1 and Lac2, respectively. In summary, these results show the potential of coffee husk as an important and economical growth medium to produce laccase, offering a new alternative use for this common agro-industrial byproduct. PMID:24019936

  3. The diving behaviour of green turtles undertaking oceanic migration to and from Ascension Island: dive durations, dive profiles and depth distribution.

    PubMed

    Hays, G C; Akesson, S; Broderick, A C; Glen, F; Godley, B J; Luschi, P; Martin, C; Metcalfe, J D; Papi, F

    2001-12-01

    Satellite telemetry was used to record the submergence duration of green turtles (Chelonia mydas) as they migrated from Ascension Island to Brazil (N=12 individuals) while time/depth recorders (TDRs) were used to examine the depth distribution and dive profiles of individuals returning to Ascension Island to nest after experimental displacement (N=5 individuals). Satellite telemetry revealed that most submergences were short (<5 min) but that some submergences were longer (>20 min), particularly at night. TDRs revealed that much of the time was spent conducting short (2-4 min), shallow (approximately 0.9-1.5 m) dives, consistent with predictions for optimisation of near-surface travelling, while long (typically 20-30 min), deep (typically 10-20 m) dives had a distinctive profile found in other marine reptiles. These results suggest that green turtles crossing the Atlantic do not behave invariantly, but instead alternate between periods of travelling just beneath the surface and diving deeper. These deep dives may have evolved to reduce silhouetting against the surface, which would make turtles more susceptible to visual predators such as large sharks.

  4. Nonlinear water waves generated by impulsive motion of submerged obstacle

    NASA Astrophysics Data System (ADS)

    Makarenko, N.; Kostikov, V.

    2012-04-01

    The fully nonlinear problem on generation of unsteady water waves by impulsively moving obstacle is studied analytically. The method involves the reduction of basic Euler equations to the integral-differential system for the wave elevation together with normal and tangential fluid velocities at the free surface. Exact model equations are derived in explicit form when the isolated obstacle is presented by totally submerged circular- or elliptic cylinder. Small-time asymptotic solution is constructed for the cylinder which starts moving with constant acceleration from rest. It is demonstrated that the leading-order solution terms describe several wave regimes such as the formation of non-stationary splash jets by vertical rising or vertical submersion of the obstacle, as well as the generation of diverging waves by horizontal- and combined motion of the obstacle under free surface. This work was supported by RFBR (grant No 10-01-00447) and by Research Program of the Russian Government (grant No 11.G34.31.0035).

  5. Fouling mechanisms of gel layer in a submerged membrane bioreactor.

    PubMed

    Hong, Huachang; Zhang, Meijia; He, Yiming; Chen, Jianrong; Lin, Hongjun

    2014-08-01

    The fouling mechanisms underlying gel layer formation and its filtration resistance in a submerged membrane bioreactor (MBR) were investigated. It was found that gel layer rather than cake layer was more easily formed when soluble microbial products content in sludge suspension was relatively high. Thermodynamic analyses showed that gel layer formation process should overcome a higher energy barrier as compared with cake layer formation process. However, when separation distance <2.3 nm, attractive interaction energy of gelling foulant-membrane combination was remarkably higher than that of sludge floc-membrane combination. The combined effects were responsible for gel layer formation. Filtration tests showed that specific filtration resistance (SFR) of gel layer was almost 100 times higher than that of cake layer. The unusually high SFR of gel layer could be ascribed to the gelling propensity and osmotic pressure mechanism. These findings shed significant light on fouling mechanisms of gel layer in MBRs. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Sputtered gold mask for deep chemical etching of silicon

    NASA Technical Reports Server (NTRS)

    Pisciotta, B. P.; Gross, C.; Olive, R. S.

    1975-01-01

    Sputtered mask resists chemical attack from acid and has adherence to withstand prolonged submergence in etch solution without lifting from silicon surface. Even under prolonged etch conditions with significant undercutting, gold mask maintained excellent adhesion to silicon surface and imperviousness to acid.

  7. A deep reef in deep trouble

    USGS Publications Warehouse

    Menza, Charles; Kendall, M.; Rogers, C.; Miller, J.

    2007-01-01

    The well-documented degradation of shallower reefs which are often closer to land and more vulnerable to pollution, sewage and other human-related stressors has led to the suggestion that deeper, more remote offshore reefs could possibly serve as sources of coral and fish larvae to replenish the shallower reefs. Yet, the distribution, status, and ecological roles of deep (>30 m) Caribbean reefs are not well known. In this report, an observation of a deep reef which has undergone a recent extensive loss of coral cover is presented. In stark contrast to the typical pattern of coral loss in shallow reefs, the deeper corals were most affected. This report is the first description of such a pattern of coral loss on a deep reef.

  8. Submergence Tolerance and Germination Dynamics of Roegneria nutans Seeds in Water-Level Fluctuation Zones with Different Water Rhythms in the Three Gorges Reservoir

    PubMed Central

    Zeng, Bo; Pan, Xiaojiao; Su, Xiaolei

    2016-01-01

    The Three Gorges Dam features two water-level fluctuation zones (WLFZs): the preupland drawdown zone (PU-DZ) and the preriparian drawdown zone (PR-DZ). To investigate the vegetation potential of Roegneria nutans in WLFZs, we compared the submergence tolerance and germination dynamics in the natural riparian zone (NRZ), PU-DZ and PR-DZ. We found that the NRZ seeds maintained an 81.3% intactness rate and >91% germination rate. The final seed germination rate and germination dynamics were consistent with those of the controls. Meanwhile, the PU-DZ seeds submerged at 5 m, 10 m, 15 m, and 20 m exhibited intactness rates of 70.5%, 79.95%, 40.75%, and 39.87%, respectively, and >75% germination. Furthermore, the PR-DZ seeds exhibited intactness rates of 22.44%, 61.13%, 81.87%, and 15.36% at 5 m, 10 m, 15 m, and 17 m, respectively, and 80% germination. The germination rates of the intact seeds submerged >10 m were >80%. Finally, the intact seeds germinated quickly in all WLFZs. The high proportion of intact seeds, rapid germination capacity, and high germination rate permit R. nutans seeds to adapt to the complicated water rhythms of the PU-DZ and PR-DZ and indicate the potential for their use in vegetation restoration and recovery. Thus, perennial seeds can be used for vegetation restoration in the WLFZs of large reservoirs and in other regions with water rhythms similar to the Three Gorges Reservoir. PMID:27031104

  9. DeepSynergy: predicting anti-cancer drug synergy with Deep Learning

    PubMed Central

    Preuer, Kristina; Lewis, Richard P I; Hochreiter, Sepp; Bender, Andreas; Bulusu, Krishna C; Klambauer, Günter

    2018-01-01

    Abstract Motivation While drug combination therapies are a well-established concept in cancer treatment, identifying novel synergistic combinations is challenging due to the size of combinatorial space. However, computational approaches have emerged as a time- and cost-efficient way to prioritize combinations to test, based on recently available large-scale combination screening data. Recently, Deep Learning has had an impact in many research areas by achieving new state-of-the-art model performance. However, Deep Learning has not yet been applied to drug synergy prediction, which is the approach we present here, termed DeepSynergy. DeepSynergy uses chemical and genomic information as input information, a normalization strategy to account for input data heterogeneity, and conical layers to model drug synergies. Results DeepSynergy was compared to other machine learning methods such as Gradient Boosting Machines, Random Forests, Support Vector Machines and Elastic Nets on the largest publicly available synergy dataset with respect to mean squared error. DeepSynergy significantly outperformed the other methods with an improvement of 7.2% over the second best method at the prediction of novel drug combinations within the space of explored drugs and cell lines. At this task, the mean Pearson correlation coefficient between the measured and the predicted values of DeepSynergy was 0.73. Applying DeepSynergy for classification of these novel drug combinations resulted in a high predictive performance of an AUC of 0.90. Furthermore, we found that all compared methods exhibit low predictive performance when extrapolating to unexplored drugs or cell lines, which we suggest is due to limitations in the size and diversity of the dataset. We envision that DeepSynergy could be a valuable tool for selecting novel synergistic drug combinations. Availability and implementation DeepSynergy is available via www.bioinf.jku.at/software/DeepSynergy. Contact klambauer

  10. Impact of submerged aquatic macrophytes on 3-dim current systems and hydrodynamic transport processes in Lake Constance

    NASA Astrophysics Data System (ADS)

    Wolf, Thomas; Lüddeke, Frauke; Thiange, Christophe

    2015-04-01

    According to the assessment criteria of the European water framework directive Lake Constance is having a good water quality. Nevertheless upcoming criteria using environmental quality measures show that there are still problems with respect to micropollutants. In fact, we observe significantly enhanced concentrations of micropollutants close to river mouths and in the areas of shallow water zones within Lake Constance compared to deep water concentrations. These findings are caused by river water plumes which can flow over distances of kilometers in the lake without being diluted or mixed only weakly with the surrounding lake water body. Besides, in the area of interest exist large populations of submerged aquatic macrophytes (SAM). There is only little knowledge, how these influence the distribution and transport processes of micropollutants. In order to assess the impact and distribution of river water plumes in different areas of the lake we implemented a 3-dim hydrodynamic model using DELFT3D-FLOW on a locally refined numerical grid which enables to cover different process scales of the distribution of river water bodies ranging from a few meters up to basin wide scales in the order of a few kilometers. We used numerical tracers (conservative and non-conservative) in order to quantify the impact of different abstract substance classes which are distinguished by their decay rates. In order to asses the influence of SAM populations on current field and transport processes we used a special simulation technique - the trachytope concept. The results of our 3-dim hydrodynamic model showed significantly changed current velocities, residence times and age of water parameters within the SAM areas compared to the control simulation without SAM. By simulating the propagation of coliform bacteria using numerical tracers with spatially and temporarily variable decay rates, we found complex impact pattern of the SAM on the distribution of these potentially harmful

  11. Effects of Oil-Contaminated Sediments on Submerged Vegetation: An Experimental Assessment of Ruppia maritima.

    PubMed

    Martin, Charles W; Hollis, Lauris O; Turner, R Eugene

    2015-01-01

    Oil spills threaten the productivity of ecosystems through the degradation of coastal flora and the ecosystem services these plants provide. While lab and field investigations have quantified the response of numerous species of emergent vegetation to oil, the effects on submerged vegetation remain uncertain. Here, we discuss the implications of oil exposure for Ruppia maritima, one of the most common species of submerged vegetation found in the region affected by the recent Deepwater Horizon oil spill. We grew R. maritima in a range of manipulated sediment oil concentrations: 0, 0.26, 0.53, and 1.05 mL oil /L tank volume, and tracked changes in growth (wet weight and shoot density/length), reproductive activity (inflorescence and seed production), root characteristics (mass, length, diameter, and area), and uprooting force of plants. While no statistical differences were detected in growth, plants exhibited significant changes to reproductive output, root morphology, and uprooting force. We found significant reductions in inflorescences and fruiting bodies at higher oil concentrations. In addition, the roots growing in the high oil were shorter and wider. Plants in medium and high oil required less force to uproot. A second experiment was performed to separate the effects of root morphology and oiled sediment properties and indicated that there were also changes to sediment cohesion that contributed to a reduction in uprooting forces in medium and high oil. Given the importance of sexual reproduction for these plants, oil contamination may have substantial population-level effects. Moreover, areas containing buried oil may be more susceptible to high energy storm events due to the reduction in uprooting force of foundation species such as R. maritima.

  12. Effects of Oil-Contaminated Sediments on Submerged Vegetation: An Experimental Assessment of Ruppia maritima

    PubMed Central

    Martin, Charles W.; Hollis, Lauris O.; Turner, R. Eugene

    2015-01-01

    Oil spills threaten the productivity of ecosystems through the degradation of coastal flora and the ecosystem services these plants provide. While lab and field investigations have quantified the response of numerous species of emergent vegetation to oil, the effects on submerged vegetation remain uncertain. Here, we discuss the implications of oil exposure for Ruppia maritima, one of the most common species of submerged vegetation found in the region affected by the recent Deepwater Horizon oil spill. We grew R. maritima in a range of manipulated sediment oil concentrations: 0, 0.26, 0.53, and 1.05 mL oil /L tank volume, and tracked changes in growth (wet weight and shoot density/length), reproductive activity (inflorescence and seed production), root characteristics (mass, length, diameter, and area), and uprooting force of plants. While no statistical differences were detected in growth, plants exhibited significant changes to reproductive output, root morphology, and uprooting force. We found significant reductions in inflorescences and fruiting bodies at higher oil concentrations. In addition, the roots growing in the high oil were shorter and wider. Plants in medium and high oil required less force to uproot. A second experiment was performed to separate the effects of root morphology and oiled sediment properties and indicated that there were also changes to sediment cohesion that contributed to a reduction in uprooting forces in medium and high oil. Given the importance of sexual reproduction for these plants, oil contamination may have substantial population-level effects. Moreover, areas containing buried oil may be more susceptible to high energy storm events due to the reduction in uprooting force of foundation species such as R. maritima. PMID:26430971

  13. Geometrical and hydrogeological impact on the behaviour of deep-seated rock slides during reservoir impoundment

    NASA Astrophysics Data System (ADS)

    Lechner, Heidrun; Zangerl, Christian

    2015-04-01

    Given that there are still uncertainties regarding the deformation and failure mechanisms of deep-seated rock slides this study concentrates on key factors that influence the behaviour of rock slides in the surrounding of reservoirs. The focus is placed on the slope geometry, hydrogeology and kinematics. Based on numerous generic rock slide models the impacts of the (i) rock slide geometry, (ii) reservoir impoundment and level fluctuations, (iii) seepage and buoyancy forces and (iv) hydraulic conductivity of the rock slide mass and the basal shear zone are examined using limit equilibrium approaches. The geometry of many deep-seated rock slides in metamorphic rocks is often influenced by geological structures, e.g. fault zones, joints, foliation, bedding planes and others. With downslope displacement the rock slide undergoes a change in shape. Several observed rock slides in an advanced stage show a convex, bulge-like topography at the foot of the slope and a concave topography in the middle to upper part. Especially, the situation of the slope toe plays an important role for stability. A potentially critical situation can result from a partially submerged flat slope toe because the uplift due to water pressure destabilizes the rock slide. Furthermore, it is essential if the basal shear zone daylights at the foot of the slope or encounters alluvial or glacial deposits at the bottom of the valley, the latter having a buttressing effect. In this study generic rock slide models with a shear zone outcropping at the slope toe are established and systematically analysed using limit equilibrium calculations. Two different kinematic types are modelled: (i) a translational or planar and (ii) a rotational movement behaviour. Questions concerning the impact of buoyancy and pore pressure forces that develop during first time impoundment are of key interest. Given that an adverse effect on the rock slide stability is expected due to reservoir impoundment the extent of

  14. Deep-sea geohazards in the South China Sea

    NASA Astrophysics Data System (ADS)

    Wu, Shiguo; Wang, Dawei; Völker, David

    2018-02-01

    Various geological processes and features that might inflict hazards identified in the South China Sea by using new technologies and methods. These features include submarine landslides, pockmark fields, shallow free gas, gas hydrates, mud diapirs and earthquake tsunami, which are widely distributed in the continental slope and reefal islands of the South China Sea. Although the study and assessment of geohazards in the South China Sea came into operation only recently, advances in various aspects are evolving at full speed to comply with National Marine Strategy and `the Belt and Road' Policy. The characteristics of geohazards in deep-water seafloor of the South China Sea are summarized based on new scientific advances. This progress is aimed to aid ongoing deep-water drilling activities and decrease geological risks in ocean development.

  15. Nuclear Technology. Course 28: Welding Inspection. Module 28-3, Tungsten Inert Gas (TIG), Metal Inert Gas (MIG) and Submerged Arc Welding.

    ERIC Educational Resources Information Center

    Espy, John

    This third in a series of ten modules for a course titled Welding Inspection presents the apparatus, process techniques, procedures, applications, associated defects, and inspection for the tungsten inert gas, metal inert gas, and submerged arc welding processes. The module follows a typical format that includes the following sections: (1)…

  16. Deep Logic Networks: Inserting and Extracting Knowledge From Deep Belief Networks.

    PubMed

    Tran, Son N; d'Avila Garcez, Artur S

    2018-02-01

    Developments in deep learning have seen the use of layerwise unsupervised learning combined with supervised learning for fine-tuning. With this layerwise approach, a deep network can be seen as a more modular system that lends itself well to learning representations. In this paper, we investigate whether such modularity can be useful to the insertion of background knowledge into deep networks, whether it can improve learning performance when it is available, and to the extraction of knowledge from trained deep networks, and whether it can offer a better understanding of the representations learned by such networks. To this end, we use a simple symbolic language-a set of logical rules that we call confidence rules-and show that it is suitable for the representation of quantitative reasoning in deep networks. We show by knowledge extraction that confidence rules can offer a low-cost representation for layerwise networks (or restricted Boltzmann machines). We also show that layerwise extraction can produce an improvement in the accuracy of deep belief networks. Furthermore, the proposed symbolic characterization of deep networks provides a novel method for the insertion of prior knowledge and training of deep networks. With the use of this method, a deep neural-symbolic system is proposed and evaluated, with the experimental results indicating that modularity through the use of confidence rules and knowledge insertion can be beneficial to network performance.

  17. Fatigue crack growth behavior of pressure vessel steels and submerged arc weldments in a high-temperature pressurized water environment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liaw, P.K.; Logsdon, W.A.; Begley, J.A.

    1989-10-01

    The fatigue crack growth rate (FCGR) properties of SA508 Cl 2a and SA533 Gr A Cl 2 pressure vessel steels and the corresponding automatic submerged arc weldments were developed in a high-temperature pressurized water (HPW) environment at 288{degrees} C (550{degrees} F) and 7.2 MPa (1044 psi) at load ratios of 0.20 and 0.50. The properties were generally conservative compared to American Society of Mechanical Engineers Section XI water environment reference curve. The growth rate of fatigue cracks in the base materials, however, was faster in the HPW environment than in a 288{degrees} C (550{degrees} F) base line air environment. Themore » growth rate of fatigue cracks in the two submerged arc weldments was also accelerated in the HPW environment but to a lesser degree than that demonstrated by the base materials. In the air environment, fatigue striations were observed, independent of material and load ratio, while in the HPW environment, some intergranular facets were present. The greater environmental effect on crack growth rates displayed by the base materials compared the weldments attributed to a different sulfide composition and morphology.« less

  18. Deep Vein Thrombosis

    MedlinePlus

    Deep vein thrombosis, or DVT, is a blood clot that forms in a vein deep in the body. Most ... vein swells, the condition is called thrombophlebitis. A deep vein thrombosis can break loose and cause a serious problem ...

  19. In-Hospital Mortality with Deep Venous Thrombosis.

    PubMed

    Stein, Paul D; Matta, Fadi; Hughes, Mary J

    2017-05-01

    Little is known about the in-hospital mortality of deep venous thrombosis in recent years. This investigation was undertaken to determine trends in in-hospital mortality in patients with deep venous thrombosis and mortality according to age. Administrative data were analyzed from the National (Nationwide) Inpatient Sample, 2003-2012. We determined in-hospital all-cause mortality according to year and age among patients with a primary (first-listed) diagnosis of deep venous thrombosis. We analyzed all such patients and we analyzed those who had none of the comorbid conditions listed in the Charlson Comorbidity Index. From 2003-2012, 1,603,690 hospitalized patients had a primary diagnosis of deep venous thrombosis. All-cause in-hospital mortality decreased from 1.3% in 2003 to 0.6% in 2012. Mortality increased with age from 0.1% in those aged 18-20 years to 1.5% in those over age 80 years. All-cause in-hospital mortality in those with no comorbid conditions according to the Charlson Comorbidity Index (1,094,184 patients) decreased from 1.1% in 2003 to 0.5% in 2012. Presumably, these deaths were from pulmonary embolism. All-cause mortality in those with no comorbid conditions increased with age from 0.1% in those aged 18-20 years to 1.4% in those over aged 80 years. All-cause death and death due to pulmonary embolism in patients hospitalized with a primary diagnosis of deep venous thrombosis decreased from 2003-2012. The death rate increased with age. The decreased mortality over the period of investigation may have resulted from a shift toward use of low-molecular-weight heparins and newer anticoagulants. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Free-surface tracking of submerged features to infer hydrodynamic flow characteristics

    NASA Astrophysics Data System (ADS)

    Mandel, Tracy; Rosenzweig, Itay; Koseff, Jeffrey

    2016-11-01

    As sea level rise and stronger storm events threaten our coastlines, increased attention has been focused on coastal vegetation as a potentially resilient, financially viable tool to mitigate flooding and erosion. However, the actual effect of this "green infrastructure" on near-shore wave fields and flow patterns is not fully understood. For example, how do wave setup, wave nonlinearity, and canopy-generated instabilities change due to complex bottom roughness? Answering this question requires detailed knowledge of the free surface. We develop easy-to-use laboratory techniques to remotely measure physical processes by imaging the apparent distortion of the fixed features of a submerged cylinder array. Measurements of surface turbulence from a canopy-generated Kelvin-Helmholtz instability are possible with a single camera. A stereoscopic approach similar to Morris (2004) and Gomit et al. (2013) allows for measurement of waveform evolution and the effect of vegetation on wave steepness and nonlinearity.

  1. Abrupt climate change and collapse of deep-sea ecosystems

    USGS Publications Warehouse

    Yasuhara, Moriaki; Cronin, T. M.; Demenocal, P.B.; Okahashi, H.; Linsley, B.K.

    2008-01-01

    We investigated the deep-sea fossil record of benthic ostracodes during periods of rapid climate and oceanographic change over the past 20,000 years in a core from intermediate depth in the northwestern Atlantic. Results show that deep-sea benthic community "collapses" occur with faunal turnover of up to 50% during major climatically driven oceanographic changes. Species diversity as measured by the Shannon-Wiener index falls from 3 to as low as 1.6 during these events. Major disruptions in the benthic communities commenced with Heinrich Event 1, the Inter-Aller??d Cold Period (IACP: 13.1 ka), the Younger Dryas (YD: 12.9-11.5 ka), and several Holocene Bond events when changes in deep-water circulation occurred. The largest collapse is associated with the YD/IACP and is characterized by an abrupt two-step decrease in both the upper North Atlantic Deep Water assemblage and species diversity at 13.1 ka and at 12.2 ka. The ostracode fauna at this site did not fully recover until ???8 ka, with the establishment of Labrador Sea Water ventilation. Ecologically opportunistic slope species prospered during this community collapse. Other abrupt community collapses during the past 20 ka generally correspond to millennial climate events. These results indicate that deep-sea ecosystems are not immune to the effects of rapid climate changes occurring over centuries or less. ?? 2008 by The National Academy of Sciences of the USA.

  2. Oxygen uptake and local Po2 profiles in submerged larvae of phaeoxantha klugii (Coleoptera: Cicindelidae), as well as their metabolic rate in air.

    PubMed

    Zerm, M; Zinkler, D; Adis, J

    2004-01-01

    We studied whether oxygen uptake from the surrounding water might enhance survival in submerged third instar larvae of Phaeoxantha klugii, a tiger beetle from the central Amazonian floodplains. Local oxygen partial pressures (Po(2)) were measured with microcoaxial needle electrodes close to larvae submerged in initially air-saturated still water. The Po(2) profiles showed that the larvae exploit oxygen from the aquatic medium. Metabolism in the air of more or less resting larvae was determined by measuring the rate of CO(2) production (sV dot co2) with an infrared gas analyzer at 29 degrees C. The sV dot co2 was around 1.8 mu L g(-1) min(-1), equivalent to an oxygen consumption rate (sV dot o2) of 1.8-2.6 mu L g(-1) min(-1). Oxygen consumption (V dot o2) of individually submerged larvae measured in closed respiration chambers at 19-10.3 kPa Po(2) (initially air saturated, 29 degrees C) ranged between 0.05 and 0.2 mu L min(-1) and was not correlated with body mass. The sV dot o2 ranged between 0.1 and 0.4 mu L min(-1), that is, 4%-22% of the metabolic rate measured in air. Mean V dot o2 decreased with declining Po(2); however, some individuals showed contrary patterns. V dot o2 was additionally measured in dormant larvae, in larvae submerged for 1-2 d in open water or for 30-49 d within sediment, as well as in larvae exposed to anoxia before the measurements. The range of V dot o2 was similar in all groups, indicating that the larvae exploit oxygen from the water whenever available. Similar V dot o2 across the whole range of body mass investigated (0.31-0.76 g) suggests that oxygen uptake occurs by spiracular uptake. Assuming that larvae survive for some time at rates comparable to depressed metabolic rates reported for other insect species, it can be concluded that oxygen uptake from water can sustain aerobic metabolism even under quite severe hypoxia. It might therefore play an important role for survival during inundation periods.

  3. Microbial community evolution of black and stinking rivers during in situ remediation through micro-nano bubble and submerged resin floating bed technology.

    PubMed

    Sun, Yanmei; Wang, Shiwei; Niu, Junfeng

    2018-06-01

    Microbes play important roles during river remediation and the interaction mechanism illustration between microorganisms and sewage is of great significance to improve restoration technology. In this study, micro-nano bubble and submerged resin floating bed composite technology (MBSR) was firstly used to restore two black and stinking urban rivers. After restoration, the water pollution indices such as dissolved oxygen (DO), ammonia nitrogen (NH 4 + -N), total phosphorous (TP), chemical oxygen demand (COD Cr ), water clarity, and the number of facial coliform were significantly improved. Microbial community composition and relative abundance both varied and more aerobic microbes emerged after remediation. The microbial changes showed correlation with DO, NH 4 + -N, TP and COD Cr of the rivers. In summary, the MBSR treatment improved the physiochemical properties of the two black and stinking urban rivers probably through oxygen enrichment of micro-nano bubble and adsorption of submerged resin floating bed, which thereby stimulated functional microbes to degrade pollutants. Copyright © 2018 Elsevier Ltd. All rights reserved.

  4. Phytase Production by Aspergillus niger CFR 335 and Aspergillus ficuum SGA 01 through Submerged and Solid-State Fermentation

    PubMed Central

    Shivanna, Gunashree B.; Venkateswaran, Govindarajulu

    2014-01-01

    Fermentation is one of the industrially important processes for the development of microbial metabolites that has immense applications in various fields. This has prompted to employ fermentation as a major technique in the production of phytase from microbial source. In this study, a comparison was made between submerged (SmF) and solid-state fermentations (SSF) for the production of phytase from Aspergillus niger CFR 335 and Aspergillus ficuum SGA 01. It was found that both the fungi were capable of producing maximum phytase on 5th day of incubation in both submerged and solid-state fermentation media. Aspergillus niger CFR 335 and A. ficuum produced a maximum of 60.6 U/gds and 38 U/gds of the enzyme, respectively, in wheat bran solid substrate medium. Enhancement in the enzyme level (76 and 50.7 U/gds) was found when grown in a combined solid substrate medium comprising wheat bran, rice bran, and groundnut cake in the ratio of 2 : 1 : 1. A maximum of 9.6 and 8.2 U/mL of enzyme activity was observed in SmF by A. niger CFR 335 and A.ficuum, respectively, when grown in potato dextrose broth. PMID:24688383

  5. Effect of the submergence, the bed form geometry, and the speed of the surface water flow on the mitigation of pesticides in agricultural ditches

    NASA Astrophysics Data System (ADS)

    Boutron, Olivier; Margoum, Christelle; Chovelon, Jean-Marc; Guillemain, CéLine; Gouy, VéRonique

    2011-08-01

    Pesticides, which have been extensively used in agriculture, have become a major environmental issue, especially regarding surface and groundwater contamination. Of particular importance are vegetated farm drainage ditches, which can play an important role in the mitigation of pesticide contamination by adsorption onto ditch bed substrates. This role is, however, poorly understood, especially regarding the influence of hydrodynamic parameters, which make it difficult to promote best management practice of these systems. We have assessed the influence of three of these parameters (speed of the surface water flow, submergence, and geometrical characteristics of the bed forms) on the transfer and adsorption of selected pesticides (isoproturon, diuron, tebuconazole, and azoxystrobin) into the bed substrate by performing experiments with a tilted experimental flume, using hemp fibers as a standard of natural organic substrates that are found at the bottom of agricultural ditches. Results show the transfer of pesticides from surface water flow into bed substrate is favored, both regarding the amounts transferred into the bed substrate and the kinetics of the transfer, when the surface water speed and the submergence increase and when the bed forms are made of rectangular shapes. Extrapolation of flume data over a distance of several hundred meters suggests that an interesting possibility for improving the mitigation of pesticides in ditches would be to increase the submergence and to favor bed forms that tend to enhance perturbations and subsequent infiltration of the surface water flow.

  6. Deep seismic sounding in northern Eurasia

    USGS Publications Warehouse

    Benz, H.M.; Unger, J.D.; Leith, W.S.; Mooney, W.D.; Solodilov, L.; Egorkin, A.V.; Ryaboy, V.Z.

    1992-01-01

    For nearly 40 years, the former Soviet Union has carried out an extensive program of seismic studies of the Earth's crust and upper mantle, known as “Deep Seismic Sounding” or DSS [Piwinskii, 1979; Zverev and Kosminskaya, 1980; Egorkin and Pavlenkova, 1981; Egorkin and Chernyshov, 1983; Scheimer and Borg, 1985]. Beginning in 1939–1940 with a series of small-scale seismic experiments near Moscow, DSS profiling has broadened into a national multiinstitutional exploration effort that has completed almost 150,000 km of profiles covering all major geological provinces of northern Eurasia [Ryaboy, 1989].

  7. Purification of an Exopolygalacturonase from Penicillium viridicatum RFC3 Produced in Submerged Fermentation.

    PubMed

    Gomes, Eleni; Leite, Rodrigo Simões Ribeiro; da Silva, Roberto; Silva, Dênis

    2009-01-01

    An exo-PG obtained from Penicillium viridicatum in submerged fermentation was purified to homogeneity. The apparent molecular weight of the enzyme was 92 kDa, optimum pH and temperature for activity were pH 5 and 50-55 degrees C. The exo-PG showed a profile of an exo-polygalacturonase, releasing galacturonic acid by hydrolysis of pectin with a high degree of esterification (D.E.). Ions Ca(2+) enhanced the stability of enzyme and its activity by 30%. The K(m) was 1.30 in absence of Ca(2+) and 1.16 mg mL(-1) in presence of this ion. In relation to the V(max) the presence of this ion increased from 1.76 to 2.07 mumol min(-1)mg(-1).

  8. Evaluation of metal ions and surfactants effect on cell growth and exopolysaccharide production in two-stage submerged culture of Cordyceps militaris.

    PubMed

    Cui, Jian-Dong; Zhang, Ya-Nan

    2012-11-01

    During the two-stage submerged fermentation of medicinal mushroom Cordyceps militaris, it was found that K(+), Ca(2+), Mg(2+), and Mn(2+) were favorable to the mycelial growth. The EPS production reached the highest levels in the media containing Mg(2+) and Mn(2+). However, Ca(2+) and K(+) almost failed to increase significantly exopolysaccharides (EPS) production. Sodium dodecyl sulfate (SDS) significantly enhanced EPS production compared with that of without adding SDS when SDS was added on static culture stage of two-stage cultivation process. The presence of Tween 80 in the medium not only simulated mycelial growth but also increased EPS production. By response surface methods (RSM), EPS production reached its peak value of 3.28 g/L under optimal combination of 27.6 mM Mg(2+), 11.1 mM Mn(2+), and 0.05 mM SDS, which was 3.76-fold compared with that of without metal ion and surfactant. The results obtained were useful in better understanding the regulation for efficient production of EPS of C. militaris in the two-stage submerged culture.

  9. Submerged Cultivation of Pleurotus sapidus with Molasses: Aroma Dilution Analyses by Means of Solid Phase Microextraction and Stir Bar Sorptive Extraction.

    PubMed

    Trapp, Tobias; Zajul, Martina; Ahlborn, Jenny; Stephan, Alexander; Zorn, Holger; Fraatz, Marco Alexander

    2018-03-14

    The basidiomycete Pleurotus sapidus (PSA) was grown in submerged cultures with molasses as substrate for the production of mycelium as a protein source for food applications. The volatilomes of the substrate, the submerged culture, and the mycelia were analyzed by gas chromatography-tandem mass spectrometry-olfactometry. For compound identification, aroma dilution analyses by means of headspace solid phase microextraction and stir bar sorptive extraction were performed via variation of the split vent flow rate. Among the most potent odorants formed by PSA were arylic compounds (e.g., p-anisaldehyde), unsaturated carbonyls (e.g., 1-octen-3-one, ( E)-2-octenal, ( E, E)-2,4-decadienal), and cyclic monoterpenoids (e.g., 3,9-epoxy- p-menth-1-ene, 3,6-dimethyl-3a,4,5,7a-tetrahydro-1-benzofuran-2(3 H)-one). Several compounds from the latter group were described for the first time in Pleurotus spp. After separation of the mycelia from the medium, the aroma compounds were mainly enriched in the culture supernatant. The sensory analysis of the mycelium correlated well with the instrumental results.

  10. Geological events in submerged areas: attributes and standards in the EMODnet Geology Project

    NASA Astrophysics Data System (ADS)

    Fiorentino, A.; Battaglini, L.; D'Angelo, S.

    2017-12-01

    EMODnet Geology is a European Project which promotes the collection and harmonization of marine geological data mapped by various national and regional mapping projects and recovered in the literature, in order to make them freely available through a web portal. Among the several features considered within the Project, "Geological events and probabilities" include submarine landslides, earthquakes, volcanic centers, tsunamis, fluid emissions and Quaternary faults in European Seas. Due to the different geological settings of European sea areas it was necessary to elaborate a comprehensive and detailed pattern of Attributes for the different features in order to represent the diverse characteristics of each occurrence. Datasets consist of shapefiles representing each event at 1:250,000 scale. The elaboration of guidelines to compile the shapefiles and attribute tables was aimed at identifying parameters that should be used to characterize events and any additional relevant information. Particular attention has been devoted to the definition of the Attribute table in order to achieve the best degree of harmonization and standardization according to the European INSPIRE Directive. One of the main objectives is the interoperability of data, in order to offer more complete, error-free and reliable information and to facilitate exchange and re-use of data even between non-homogeneous systems. Metadata and available information collected during the Project is displayed on the Portal (http://www.emodnet-geology.eu/) as polygons, lines and points layers according to their geometry. By combining all these data it might be possible to elaborate additional thematic maps which could support further research as well as land planning and management. A possible application is being experimented by the Geological Survey of Italy - ISPRA which, in cooperation with other Italian institutions contributing to EMODnet Geology, is working at the production of an update for submerged areas

  11. Underwater Photosynthesis of Submerged Plants – Recent Advances and Methods

    PubMed Central

    Pedersen, Ole; Colmer, Timothy D.; Sand-Jensen, Kaj

    2013-01-01

    We describe the general background and the recent advances in research on underwater photosynthesis of leaf segments, whole communities, and plant dominated aquatic ecosystems and present contemporary methods tailor made to quantify photosynthesis and carbon fixation under water. The majority of studies of aquatic photosynthesis have been carried out with detached leaves or thalli and this selectiveness influences the perception of the regulation of aquatic photosynthesis. We thus recommend assessing the influence of inorganic carbon and temperature on natural aquatic communities of variable density in addition to studying detached leaves in the scenarios of rising CO2 and temperature. Moreover, a growing number of researchers are interested in tolerance of terrestrial plants during flooding as torrential rains sometimes result in overland floods that inundate terrestrial plants. We propose to undertake studies to elucidate the importance of leaf acclimation of terrestrial plants to facilitate gas exchange and light utilization under water as these acclimations influence underwater photosynthesis as well as internal aeration of plant tissues during submergence. PMID:23734154

  12. 46 CFR 117.207 - Survival craft-vessels operating on lakes, bays, and sounds routes.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... survival craft. (e) For a vessel certificated to operate on a lakes, bays, and sounds route in shallow water where the vessel can not sink deep enough to submerge the topmost passenger deck or where...

  13. Coastline shifts and probable ship landing site submerged off ancient Locri-Epizefiri, southern Italy

    USGS Publications Warehouse

    Tennent, J.M.; Stanley, J.-D.; Hart, P.E.; Bernasconi, M.P.

    2009-01-01

    A geophysical survey provides new information on marine features located seaward of Locri-Epizefiri (Locri), an ancient Greek settlement on the Ionian coastal margin in southern Italy. The study supplements previous work by archaeologists who long searched for the site's harbor and recently identified what was once a marine basin that is now on land next to the city walls of Locri. Profiles obtained offshore, between the present coast and outer shelf, made with a high-resolution, seismic subbottom-profiling system, record spatial and temporal variations of buried Holocene deposits. Two of these submerged features are part of a probable now-submerged ship landing facility. The offshore features can be linked to coastline displacements that occurred off Locri: a sea-to-land shift before Greek settlement, followed by a shoreline reversal from the archaeological site back to sea, and more recently, a return landward. The seaward directed coastal shift that occurred after Locri's occupation by Greeks was likely caused by land uplift near the coastal margin and tectonic seaward shift of the coast, as documented along this geologically active sector of the Calabrian Arc. The seismic survey records an angular, hook-shaped, low rise that extends from the present shore and is now buried on the inner shelf. The rise, enclosing a core lens of poorly stratified to transparent acoustic layers, bounds a broad, low-elevation zone positioned immediately seaward of the shoreline. Close proximity of the raised feature to the low-elevation area suggests it may have been a fabricated structure that functioned as a wave-break for a ship-landing site. The study indicates that the basin extended offshore as a function of the coastline's seaward migration during and/or after Greek occupation of Locri.

  14. Distribution and abundance of submerged aquatic macrophytes in a reactor cooling reservoir

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Grace, J.B.

    1977-08-01

    Measurements of ash-free dry weight were used to characterize the effects of a heated effluent on submerged macrophytes in a reactor cooling reservoir. The species which were most abundant during the summers of 1974 and 1975 were Myriophyllum spicatum L. and Eleocharis acicularis (L.) R. and S. Examination of the vertical distribution of the shoot biomass of Myriophyllum revealed that plants in heated areas grew closer to the water surface than plants in unheated areas. The biomass of the second most abundant species, Eleocharis acicularis, was less at 0.5 m depths in heated areas (more than 5C/sup 0/ warmer thanmore » unheated areas) than at equal depths in unheated areas. Species diversity was greater at heated locations because of a greater equitability (i.e., evenness of distribution of biomass) among species.« less

  15. Deep Space Telecommunications

    NASA Technical Reports Server (NTRS)

    Kuiper, T. B. H.; Resch, G. M.

    2000-01-01

    The increasing load on NASA's deep Space Network, the new capabilities for deep space missions inherent in a next-generation radio telescope, and the potential of new telescope technology for reducing construction and operation costs suggest a natural marriage between radio astronomy and deep space telecommunications in developing advanced radio telescope concepts.

  16. DEEP: A Database of Energy Efficiency Performance to Accelerate Energy Retrofitting of Commercial Buildings

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hoon Lee, Sang; Hong, Tianzhen; Sawaya, Geof

    The paper presents a method and process to establish a database of energy efficiency performance (DEEP) to enable quick and accurate assessment of energy retrofit of commercial buildings. DEEP was compiled from results of about 35 million EnergyPlus simulations. DEEP provides energy savings for screening and evaluation of retrofit measures targeting the small and medium-sized office and retail buildings in California. The prototype building models are developed for a comprehensive assessment of building energy performance based on DOE commercial reference buildings and the California DEER prototype buildings. The prototype buildings represent seven building types across six vintages of constructions andmore » 16 California climate zones. DEEP uses these prototypes to evaluate energy performance of about 100 energy conservation measures covering envelope, lighting, heating, ventilation, air-conditioning, plug-loads, and domestic hot water. DEEP consists the energy simulation results for individual retrofit measures as well as packages of measures to consider interactive effects between multiple measures. The large scale EnergyPlus simulations are being conducted on the super computers at the National Energy Research Scientific Computing Center of Lawrence Berkeley National Laboratory. The pre-simulation database is a part of an on-going project to develop a web-based retrofit toolkit for small and medium-sized commercial buildings in California, which provides real-time energy retrofit feedback by querying DEEP with recommended measures, estimated energy savings and financial payback period based on users’ decision criteria of maximizing energy savings, energy cost savings, carbon reduction, or payback of investment. The pre-simulated database and associated comprehensive measure analysis enhances the ability to performance assessments of retrofits to reduce energy use for small and medium buildings and business owners who typically do not have resources to

  17. Cold Flow Determination of the Internal Flow Environment Around the Submerged TVC Nozzle for the Space Shuttle SRM

    NASA Technical Reports Server (NTRS)

    Whitesides, R. H.; Ghosh, A.; Jenkins, S. L.; Bacchus, D. L.

    1989-01-01

    A series of subscale cold flow tests was performed to quantify the gas flow characteristics at the aft end of the Space Shuttle Solid Rocket Motor. This information was used to support the analyses of the redesigned nozzle/case joint. A portion of the thermal loads at the joint are due to the circumferential velocities and pressure gradients caused primarily by the gimbaling of the submerged nose TVC nozzle. When the nozzle centerline is vectored with respect to the motor centerline, asymmetries are set up in the flow field under the submerged nozzle and immediately adjacent to the nozzle/case joint. Specific program objectives included: determination of the effects of nozzle gimbal angle and propellant geometry on the circumferential flow field; measurement of the static pressure and gas velocities in the vicinity of the nozzle/case joint; use of scaling laws to apply the subscale cold flow data to the full scale SRM; and generation of data for use in validation of 3-D computational fluid dynamic, CFD, models of the SRM flow field. These tests were conducted in the NASA Marshall Space Flight Center Airflow Facility with a 7.5 percent scale model of the aft segment of the SRM. Static and dynamic pressures were measured in the model to quantify the flow field. Oil flow data was also acquired to obtain qualitative visual descriptions of the flow field. Nozzle gimbal angles of 0, 3.5, and 7 deg were used with propellant grain configurations corresponding to motor burn times of 0, 9, 19, and 114 seconds. This experimental program was successful in generating velocity and pressure gradient data for the flow field around the submerged nose nozzle of the Space Shuttle SRM at various burn times and gimbal angles. The nature of the flow field adjacent to the nozzle/case joint was determined with oil droplet streaks, and the velocity and pressure gradients were quantified with pitot probes and wall static pressure measurements. The data was applied to the full scale SRM thru

  18. Preliminary investigation of submerged aquatic vegetation mapping using hyperspectral remote sensing.

    PubMed

    William, David J; Rybicki, Nancy B; Lombana, Alfonso V; O'Brien, Tim M; Gomez, Richard B

    2003-01-01

    The use of airborne hyperspectral remote sensing imagery for automated mapping of submerged aquatic vegetation (SAV) in the tidal Potomac River was investigated for near to real-time resource assessment and monitoring. Airborne hyperspectral imagery and field spectrometer measurements were obtained in October of 2000. A spectral library database containing selected ground-based and airborne sensor spectra was developed for use in image processing. The spectral library is used to automate the processing of hyperspectral imagery for potential real-time material identification and mapping. Field based spectra were compared to the airborne imagery using the database to identify and map two species of SAV (Myriophyllum spicatum and Vallisneria americana). Overall accuracy of the vegetation maps derived from hyperspectral imagery was determined by comparison to a product that combined aerial photography and field based sampling at the end of the SAV growing season. The algorithms and databases developed in this study will be useful with the current and forthcoming space-based hyperspectral remote sensing systems.

  19. Combined submerged and solid substrate fermentation for the bioconversion of lignocellulose

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Viesturs, U.E.; Strikauska, S.V.; Leite, M.P.

    1987-01-01

    A novel two-stage bioreactor has been designed for a combined submerged (SF) and solid substrate fermentation (SSF) of wheat straw. The straw was pretreated with steam, and cellulases from the culture fluid of Trichoderma reesei were adsorbed on it for increased bio-convertibility. SSF was conducted in the top part of the bioreactor by inoculating the straw with a 36-h mycelial culture of T. reesei, or Coriolus versicolor. In the bottom part of the fermenter, Endomycopsis fibuliger was grown in SF. The SF liquor was recirculated through the SSF stage at 24 hour intervals to remove glucose and other metabolites thatmore » may inhibit growth, and to maintain optimum moisture level and temperature. The removed glucose and other metabolites provided nutrients for the yeast in the SF stage. The combined fermentation resulted in overall higher biomass yield, increased bioconversion, increased cellulase production, and increased digestibility compared with single SSF or SF. (Refs. 16).« less

  20. Surface wave energy absorption by a partially submerged bio-inspired canopy.

    PubMed

    Nové-Josserand, C; Castro Hebrero, F; Petit, L-M; Megill, W M; Godoy-Diana, R; Thiria, B

    2018-03-27

    Aquatic plants are known to protect coastlines and riverbeds from erosion by damping waves and fluid flow. These flexible structures absorb the fluid-borne energy of an incoming fluid by deforming mechanically. In this paper we focus on the mechanisms involved in these fluid-elasticity interactions, as an efficient energy harvesting system, using an experimental canopy model in a wave tank. We study an array of partially-submerged flexible structures that are subjected to the action of a surface wave field, investigating in particular the role of spacing between the elements of the array on the ability of our system to absorb energy from the flow. The energy absorption potential of the canopy model is examined using global wave height measurements for the wave field and local measurements of the elastic energy based on the kinematics of each element of the canopy. We study different canopy arrays and show in particular that flexibility improves wave damping by around 40%, for which half is potentially harvestable.

  1. Viscous Effects on Wave Forces on A Submerged Horizontal Circular Cylinder

    NASA Astrophysics Data System (ADS)

    Teng, Bin; Mao, Hong-Fei; Lu, Lin

    2018-06-01

    Numerical simulations are carried out for wave action on a submerged horizontal circular cylinder by means of a viscous fluid model, and it is focused on the examination of the discrepancies between the viscous fluid results and the potential flow solutions. It is found that the lift force resulted from rotational flow on the circular cylinder is always in anti-phase with the inertia force and induces the discrepancies between the results. The influence factors on the magnitude of the lift force, especially the correlation between the stagnation-point position and the wave amplitude, and the effect of the vortex shedding are investigated by further examination on the flow fields around the cylinder. The viscous numerical calculations at different wave frequencies showed that the wave frequency has also significant influence on the wave forces. Under higher frequency and larger amplitude wave action, vortex shedding from the circular cylinder will appear and influence the wave forces on the cylinder substantially.

  2. Analysis of Manning’s and Drag Coefficients for Flexible Submerged Vegetation

    NASA Astrophysics Data System (ADS)

    Yusof, Khamaruzaman Wan; Mujahid Muhammad, Muhammad; Mustafa, Muhammad Raza Ul; Azazi Zakaria, Nor; Gahani, Aminuddin Ab.

    2017-06-01

    Accurate determination of flow resistance is of great significance in modelling of open channels that will convey water efficiently. Although, resistance or drag induced by vegetation have been systematically studied for several decades, estimating of the resistance remain as a challenge. This is because most of previous studies use artificial vegetation to investigate flow - vegetation interactions. To overcome this, the present study evaluates the vegetation resistance in terms of Manning’s roughness coefficient and drag coefficient using a natural flexible vegetation (cow grass) under submerged condition. From the experimental result obtained, it was observed that the Manning’s and drag coefficients decreased with the increasing in average velocity. Also, graphical relationship between Manning’s coefficient, n and drag coefficient, CD has been developed with R2 = 0.9465, which indicate that there exist a strong correlation between n and CD, and one can use the proposed graphical model to predict the n - values corresponding to the CD - values.

  3. Compendium of the ULF/ELF Electromagnetic Fields Generated above a Sea of Finite Depth by Submerged Harmonic Dipoles

    DTIC Science & Technology

    1980-01-01

    CATALOG NUMBER Tech. Report No. E715-1 4. TTE (ln tlitts LTYPE RPOT’ QcOIJj. Compendium of the ULF/ELF Electromagnetic Fields nccnicat Generated above...sidi if noeess’ry arid Identify hy bulock mriifi.rnb) ULF/ELF Electromagnetic Fields VMD, VED, HED, HMD Submerged Dipoles Undersea /Air Communication...a whole, it appears that the vertical electric component produced by th HED in the plane of the dipole (• =0) should be the most useful for undersea

  4. Drinking water treatment using a submerged internal-circulation membrane coagulation reactor coupled with permanganate oxidation.

    PubMed

    Zhang, Zhongguo; Liu, Dan; Qian, Yu; Wu, Yue; He, Peiran; Liang, Shuang; Fu, Xiaozheng; Li, Jiding; Ye, Changqing

    2017-06-01

    A submerged internal circulating membrane coagulation reactor (MCR) was used to treat surface water to produce drinking water. Polyaluminum chloride (PACl) was used as coagulant, and a hydrophilic polyvinylidene fluoride (PVDF) submerged hollow fiber microfiltration membrane was employed. The influences of trans-membrane pressure (TMP), zeta potential (ZP) of the suspended particles in raw water, and KMnO 4 dosing on water flux and the removal of turbidity and organic matter were systematically investigated. Continuous bench-scale experiments showed that the permeate quality of the MCR satisfied the requirement for a centralized water supply, according to the Standards for Drinking Water Quality of China (GB 5749-2006), as evaluated by turbidity (<1 NTU) and total organic carbon (TOC) (<5mg/L) measurements. Besides water flux, the removal of turbidity, TOC and dissolved organic carbon (DOC) in the raw water also increased with increasing TMP in the range of 0.01-0.05MPa. High ZP induced by PACl, such as 5-9mV, led to an increase in the number of fine and total particles in the MCR, and consequently caused serious membrane fouling and high permeate turbidity. However, the removal of TOC and DOC increased with increasing ZP. A slightly positive ZP, such as 1-2mV, corresponding to charge neutralization coagulation, was favorable for membrane fouling control. Moreover, dosing with KMnO 4 could further improve the removal of turbidity and DOC, thereby mitigating membrane fouling. The results are helpful for the application of the MCR in producing drinking water and also beneficial to the research and application of other coagulation and membrane separation hybrid processes. Copyright © 2016. Published by Elsevier B.V.

  5. Deep Web video

    ScienceCinema

    None Available

    2018-02-06

    To make the web work better for science, OSTI has developed state-of-the-art technologies and services including a deep web search capability. The deep web includes content in searchable databases available to web users but not accessible by popular search engines, such as Google. This video provides an introduction to the deep web search engine.

  6. Biogeochemistry of a submerged groundwater seep ecosystem in Lake Huron near karst region of Alpena, MI

    NASA Astrophysics Data System (ADS)

    Kinsman-Costello, L. E.; Dick, G.; Sheik, C.; Burton, G. A.; Sheldon, N. D.

    2015-12-01

    Submerged groundwater seeps in Lake Huron establish ecosystems with distinctive geochemical conditions. In the Middle Island Sinkhole (MIS), a 23-m deep seep, groundwater seepage establishes low O2 (< 4 mg L-1), high sulfate (6 mM) conditions, in which a purple cyanobacteria-dominated mat thrives. The mat is capable of anoxygenic photosynthesis, oxygenic photosynthesis, and chemosynthesis. Within the top 3 cm of the mat-water interface, hydrogen sulfide concentrations increase to 1-7 mM. Little is known about the structure and function of microbes within organic-rich, high-sulfide sediments beneath the mat. Using pore water and sediment geochemical characterization along with microbial community analysis, we elucidated relationships between microbial community structure and ecosystem function along vertical gradients. In sediment pore waters, biologically reactive solutes (SO42-, NH4+, PO43-, and CH4) displayed steep vertical gradients, reflecting biological and geochemical functioning. In contrast, more conservative ions (Ca+2, Mg+2, Na+, and Cl-), did not change significantly with depth in MIS sediments, indicating groundwater influence in the sediment profile. MIS sediments contained more organic matter than typical Lake Huron sediments, and were generally higher in nutrients, metals, and sulfur (acid volatile sulfide). Using the Illumina MiSeq platform we detected 14,127 unique operational taxonomic units across sediment and surface mat samples. Microbial community composition in the MIS was distinctly different from non-groundwater affected areas at similar depth nearby in Lake Huron (ANOSIM, R= 0.74, p=0.002). MIS sediment communities were more diverse that MIS surface mat communities and changed with depth into sediments. MIS sediment community composition was related to several geochemical variables, including organic matter and multiple indicators of phosphorus availability. Elucidating the structure and function of microbial consortia in MIS, a highly

  7. Site Characterization for a Deep Borehole Field Test

    NASA Astrophysics Data System (ADS)

    Kuhlman, K. L.; Hardin, E. L.; Freeze, G. A.; Sassani, D.; Brady, P. V.

    2015-12-01

    The US Department of Energy Office of Nuclear Energy is at the beginning of 5-year Deep Borehole Field Test (DBFT) to investigate the feasibility of constructing and characterizing two boreholes in crystalline basement rock to a depth of 5 km (16,400 ft). The concept of deep borehole disposal for radioactive waste has some advantages over mined repositories, including incremental construction and loading, the enhanced natural barriers provided by deep continental crystalline basement, and reduced site characterization. Site characterization efforts need to determine an eligible site that does not have the following disqualifying characteristics: greater than 2 km to crystalline basement, upward vertical fluid potential gradients, presence of economically exploitable natural resources, presence of high permeability connection to the shallow subsurface, and significant probability of future seismic or volcanic activity. Site characterization activities for the DBFT will include geomechanical (i.e., rock in situ stress state, and fluid pressure), geological (i.e., rock and fracture infill lithology), hydrological (i.e., quantity of fluid, fluid convection properties, and solute transport mechanisms), and geochemical (i.e., rock-water interaction and natural tracers) aspects. Both direct (i.e., sampling and in situ testing) and indirect (i.e., borehole geophysical) methods are planned for efficient and effective characterization of these site aspects and physical processes. Borehole-based characterization will be used to determine the variability of system state (i.e., stress, pressure, temperature, and chemistry) with depth, and interpretation of material and system parameters relevant to numerical site simulation. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE

  8. DeepInfer: open-source deep learning deployment toolkit for image-guided therapy

    NASA Astrophysics Data System (ADS)

    Mehrtash, Alireza; Pesteie, Mehran; Hetherington, Jorden; Behringer, Peter A.; Kapur, Tina; Wells, William M.; Rohling, Robert; Fedorov, Andriy; Abolmaesumi, Purang

    2017-03-01

    Deep learning models have outperformed some of the previous state-of-the-art approaches in medical image analysis. Instead of using hand-engineered features, deep models attempt to automatically extract hierarchical representations at multiple levels of abstraction from the data. Therefore, deep models are usually considered to be more flexible and robust solutions for image analysis problems compared to conventional computer vision models. They have demonstrated significant improvements in computer-aided diagnosis and automatic medical image analysis applied to such tasks as image segmentation, classification and registration. However, deploying deep learning models often has a steep learning curve and requires detailed knowledge of various software packages. Thus, many deep models have not been integrated into the clinical research work ows causing a gap between the state-of-the-art machine learning in medical applications and evaluation in clinical research procedures. In this paper, we propose "DeepInfer" - an open-source toolkit for developing and deploying deep learning models within the 3D Slicer medical image analysis platform. Utilizing a repository of task-specific models, DeepInfer allows clinical researchers and biomedical engineers to deploy a trained model selected from the public registry, and apply it to new data without the need for software development or configuration. As two practical use cases, we demonstrate the application of DeepInfer in prostate segmentation for targeted MRI-guided biopsy and identification of the target plane in 3D ultrasound for spinal injections.

  9. DeepInfer: Open-Source Deep Learning Deployment Toolkit for Image-Guided Therapy.

    PubMed

    Mehrtash, Alireza; Pesteie, Mehran; Hetherington, Jorden; Behringer, Peter A; Kapur, Tina; Wells, William M; Rohling, Robert; Fedorov, Andriy; Abolmaesumi, Purang

    2017-02-11

    Deep learning models have outperformed some of the previous state-of-the-art approaches in medical image analysis. Instead of using hand-engineered features, deep models attempt to automatically extract hierarchical representations at multiple levels of abstraction from the data. Therefore, deep models are usually considered to be more flexible and robust solutions for image analysis problems compared to conventional computer vision models. They have demonstrated significant improvements in computer-aided diagnosis and automatic medical image analysis applied to such tasks as image segmentation, classification and registration. However, deploying deep learning models often has a steep learning curve and requires detailed knowledge of various software packages. Thus, many deep models have not been integrated into the clinical research workflows causing a gap between the state-of-the-art machine learning in medical applications and evaluation in clinical research procedures. In this paper, we propose "DeepInfer" - an open-source toolkit for developing and deploying deep learning models within the 3D Slicer medical image analysis platform. Utilizing a repository of task-specific models, DeepInfer allows clinical researchers and biomedical engineers to deploy a trained model selected from the public registry, and apply it to new data without the need for software development or configuration. As two practical use cases, we demonstrate the application of DeepInfer in prostate segmentation for targeted MRI-guided biopsy and identification of the target plane in 3D ultrasound for spinal injections.

  10. DeepInfer: Open-Source Deep Learning Deployment Toolkit for Image-Guided Therapy

    PubMed Central

    Mehrtash, Alireza; Pesteie, Mehran; Hetherington, Jorden; Behringer, Peter A.; Kapur, Tina; Wells, William M.; Rohling, Robert; Fedorov, Andriy; Abolmaesumi, Purang

    2017-01-01

    Deep learning models have outperformed some of the previous state-of-the-art approaches in medical image analysis. Instead of using hand-engineered features, deep models attempt to automatically extract hierarchical representations at multiple levels of abstraction from the data. Therefore, deep models are usually considered to be more flexible and robust solutions for image analysis problems compared to conventional computer vision models. They have demonstrated significant improvements in computer-aided diagnosis and automatic medical image analysis applied to such tasks as image segmentation, classification and registration. However, deploying deep learning models often has a steep learning curve and requires detailed knowledge of various software packages. Thus, many deep models have not been integrated into the clinical research workflows causing a gap between the state-of-the-art machine learning in medical applications and evaluation in clinical research procedures. In this paper, we propose “DeepInfer” – an open-source toolkit for developing and deploying deep learning models within the 3D Slicer medical image analysis platform. Utilizing a repository of task-specific models, DeepInfer allows clinical researchers and biomedical engineers to deploy a trained model selected from the public registry, and apply it to new data without the need for software development or configuration. As two practical use cases, we demonstrate the application of DeepInfer in prostate segmentation for targeted MRI-guided biopsy and identification of the target plane in 3D ultrasound for spinal injections. PMID:28615794

  11. DeepNeuron: an open deep learning toolbox for neuron tracing.

    PubMed

    Zhou, Zhi; Kuo, Hsien-Chi; Peng, Hanchuan; Long, Fuhui

    2018-06-06

    Reconstructing three-dimensional (3D) morphology of neurons is essential for understanding brain structures and functions. Over the past decades, a number of neuron tracing tools including manual, semiautomatic, and fully automatic approaches have been developed to extract and analyze 3D neuronal structures. Nevertheless, most of them were developed based on coding certain rules to extract and connect structural components of a neuron, showing limited performance on complicated neuron morphology. Recently, deep learning outperforms many other machine learning methods in a wide range of image analysis and computer vision tasks. Here we developed a new Open Source toolbox, DeepNeuron, which uses deep learning networks to learn features and rules from data and trace neuron morphology in light microscopy images. DeepNeuron provides a family of modules to solve basic yet challenging problems in neuron tracing. These problems include but not limited to: (1) detecting neuron signal under different image conditions, (2) connecting neuronal signals into tree(s), (3) pruning and refining tree morphology, (4) quantifying the quality of morphology, and (5) classifying dendrites and axons in real time. We have tested DeepNeuron using light microscopy images including bright-field and confocal images of human and mouse brain, on which DeepNeuron demonstrates robustness and accuracy in neuron tracing.

  12. Deep-sea faunal communities associated with a lost intermodal shipping container in the Monterey Bay National Marine Sanctuary, CA.

    PubMed

    Taylor, Josi R; DeVogelaere, Andrew P; Burton, Erica J; Frey, Oren; Lundsten, Lonny; Kuhnz, Linda A; Whaling, P J; Lovera, Christopher; Buck, Kurt R; Barry, James P

    2014-06-15

    Carrying assorted cargo and covered with paints of varying toxicity, lost intermodal containers may take centuries to degrade on the deep seafloor. In June 2004, scientists from Monterey Bay Aquarium Research Institute (MBARI) discovered a recently lost container during a Remotely Operated Vehicle (ROV) dive on a sediment-covered seabed at 1281 m depth in Monterey Bay National Marine Sanctuary (MBNMS). The site was revisited by ROV in March 2011. Analyses of sediment samples and high-definition video indicate that faunal assemblages on the container's exterior and the seabed within 10 m of the container differed significantly from those up to 500 m. The container surface provides hard substratum for colonization by taxa typically found in rocky habitats. However, some key taxa that dominate rocky areas were absent or rare on the container, perhaps related to its potential toxicity or limited time for colonization and growth. Ecological effects appear to be restricted to the container surface and the benthos within ∼10 m. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  13. Response of soil physico-chemical properties to restoration approaches and submergence in the water level fluctuation zone of the Danjiangkou Reservoir, China.

    PubMed

    Shu, Xiao; Zhang, KeRong; Zhang, QuanFa; Wang, WeiBo

    2017-11-01

    With the completion of the Danjiangkou Dam, the impoundment and drainage of dams can significantly alter shorelines, hydrological regime, and sediment and can result in the loss of soil and original riparian vegetation. Revegetation may affect soil properties and have broad important implications both for ecological services and soil recovery. In this work, we investigated the soil properties under different restoration approaches, and before and after submergence in the water level fluctuation zone (WLFZ) of the Danjiangkou Reservoir. Soil physical (bulk density and soil moisture), chemical (pH, soil organic carbon, nitrogen, phosphorus and potassium contents), and heavy metals were determined. This study reported that restoration approaches have impacts on soil moisture, pH, N, soil organic carbon, P, K and heavy metals in the WLFZ of the Danjiangkou Reservoir. Our results indicated that different restoration approaches could increase the soil moisture while decrease soil pH. Higher soil organic carbon in propagule banks transplantation (PBT) and shrubs restoration (SR) indicate that PBT and SR may provide soil organic matter more quickly than trees restoration (TR). SR and TR could significantly improve the soil total P and available P. PBT and SR could improve the soil total K and available K. SR and TR could significantly promote Cu and Zn adsorption, and Pb and Fe release by plant. Submergence could significantly affect the soil pH, NO 3 - -N, NH 4 + -N, total P and available P. Submergence could promote NO 3 - -N and available P adsorption, and NH 4 + -N and total P release by soil. The soil quality index (SQI) values implied that TR and PBT greatly improved soil quality. The present study suggests that PBT and TR could be effective for soil restoration in WLFZ of the Danjiangkou Reservoir. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Combined effects of phosphate-solubilizing bacterium XMT-5 (Rhizobium sp.) and submerged macrophyte Ceratophyllum demersum on phosphorus release in eutrophic lake sediments.

    PubMed

    Li, Haifeng; Li, Zhijian; Qu, Jianhang; Tian, Hailong; Yang, Xiaohong

    2018-05-02

    Simulation experiments were conducted using sediments collected from the Taihu Lake to determine the combined effects of submerged macrophytes Ceratophyllum demersum and phosphate-solubilizing bacteria (PSB) strain XMT-5 (Rhizobium sp.) on phosphorus (P) concentrations in overlying waters and sediments. After 30 days of experimental incubation, the total phosphorus (TP) and dissolved total phosphorus (DTP) concentrations of the overlying water subjected to AMB and AHMB treatments (both with the combined effects of PSB cells and submerged macrophytes) were generally lower than those of the AM (with individual effects of inoculated C. demersum) and AB (with individual effects of a smaller amount of inoculated PSB cells) control treatments but higher than that of the A (with no effects of inoculated PSB cells or C. demersum) and AHB (with individual effects of a larger amount of inoculated PSB) control treatments. The TP contents of the sediment in the AMB and AHMB treatments were significantly lower than those of the other control treatments. The TP contents of the C. demersum cocultured with the PSB strain XMT-5 cells in the AMB and AHMB treatments were all significantly higher than that of the AM treatment, indicating the enhancement of P uptake by submerged plants inoculated with PSB. The bacterial diversity structures of the rhizosphere sediment subjected to different treatments were also analyzed by the high-throughput sequencing method. According to the ACE and Chao 1 indices, the bacterial diversity in the AMB and AHMB treatments were the highest. Although many sources contributed to the decrease in the nutrient loads of the lake sediment, harvesting macrophytes inoculated with PSB cells prior to their senescence might constitute a significant in-lake measure for reducing internal P load.

  15. Deep Space Network Antenna Monitoring Using Adaptive Time Series Methods and Hidden Markov Models

    NASA Technical Reports Server (NTRS)

    Smyth, Padhraic; Mellstrom, Jeff

    1993-01-01

    The Deep Space Network (DSN)(designed and operated by the Jet Propulsion Laboratory for the National Aeronautics and Space Administration (NASA) provides end-to-end telecommunication capabilities between earth and various interplanetary spacecraft throughout the solar system.

  16. Purification of an Exopolygalacturonase from Penicillium viridicatum RFC3 Produced in Submerged Fermentation

    PubMed Central

    Gomes, Eleni; Leite, Rodrigo Simões Ribeiro; da Silva, Roberto; Silva, Dênis

    2009-01-01

    An exo-PG obtained from Penicillium viridicatum in submerged fermentation was purified to homogeneity. The apparent molecular weight of the enzyme was 92 kDa, optimum pH and temperature for activity were pH 5 and 50–55°C. The exo-PG showed a profile of an exo-polygalacturonase, releasing galacturonic acid by hydrolysis of pectin with a high degree of esterification (D.E.). Ions Ca2+ enhanced the stability of enzyme and its activity by 30%. The K m was 1.30 in absence of Ca2+ and 1.16 mg mL−1 in presence of this ion. In relation to the V max the presence of this ion increased from 1.76 to 2.07 μmol min−1mg−1. PMID:20148174

  17. Wave energy absorption by a submerged air bag connected to a rigid float.

    PubMed

    Kurniawan, A; Chaplin, J R; Hann, M R; Greaves, D M; Farley, F J M

    2017-04-01

    A new wave energy device features a submerged ballasted air bag connected at the top to a rigid float. Under wave action, the bag expands and contracts, creating a reciprocating air flow through a turbine between the bag and another volume housed within the float. Laboratory measurements are generally in good agreement with numerical predictions. Both show that the trajectory of possible combinations of pressure and elevation at which the device is in static equilibrium takes the shape of an S. This means that statically the device can have three different draughts, and correspondingly three different bag shapes, for the same pressure. The behaviour in waves depends on where the mean pressure-elevation condition is on the static trajectory. The captured power is highest for a mean condition on the middle section.

  18. Wave energy absorption by a submerged air bag connected to a rigid float

    PubMed Central

    Chaplin, J. R.; Hann, M. R.; Greaves, D. M.; Farley, F. J. M.

    2017-01-01

    A new wave energy device features a submerged ballasted air bag connected at the top to a rigid float. Under wave action, the bag expands and contracts, creating a reciprocating air flow through a turbine between the bag and another volume housed within the float. Laboratory measurements are generally in good agreement with numerical predictions. Both show that the trajectory of possible combinations of pressure and elevation at which the device is in static equilibrium takes the shape of an S. This means that statically the device can have three different draughts, and correspondingly three different bag shapes, for the same pressure. The behaviour in waves depends on where the mean pressure-elevation condition is on the static trajectory. The captured power is highest for a mean condition on the middle section. PMID:28484330

  19. Enzymatic formation of gold nanoparticles by submerged culture of the basidiomycete Lentinus edodes.

    PubMed

    Vetchinkina, Elena P; Loshchinina, Ekaterina A; Burov, Andrey M; Dykman, Lev A; Nikitina, Valentina E

    2014-07-20

    We report for the first time that the medicinal basidiomycete Lentinus edodes can reduce Au(III) from chloroauric acid (HAuCl4) to elemental Au [Au(0)], forming nanoparticles. Several methods, including transmission electron microscopy, electron energy loss spectroscopy, X-ray fluorescence, and dynamic light scattering, were used to show that when the fungus was grown submerged, colloidal gold accumulated on the surface of and inside the mycelial hyphae as electron-dense particles mostly spherical in shape, with sizes ranging from 5 to 50nm. Homogeneous proteins (the fungal enzymes laccase, tyrosinase, and Mn-peroxidase) were found for the first time to be involved in the reduction of Au(III) to Au(0) from HAuCl4. A possible mechanism forming Au nanoparticles is discussed. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Performance of a pilot-scale submerged membrane bioreactor (MBR) in treating bathing wastewater.

    PubMed

    Xia, Siqing; Guo, Jifeng; Wang, Rongchang

    2008-10-01

    Bathing wastewater was treated by a pilot-scale submerged membrane bioreactor (MBR) for more than 60 days. The results showed that the removal rates of main pollutants of wastewater such as COD(Cr), LAS, NH(4)(+)-N and total nitrogen (TN) were above 93%, 99%, 99%, and 90%, respectively. The results of denaturing gel gradient electrophoresis (DGGE) and fluorescent in situ hybridization (FISH) indicated that the bacteria were stable. The abundant nitrobacteria intercepted by the membrane led to the high removal rate of ammonia and TN. FISH and 16S rDNA gene sequence analysis revealed that some specific phylogenetic group of bacteria, the Pseudomonas sp. Ochrobactrum anthropi sp. and Enterobacter sp. probably played a major role in the development of the mature biofilms, which led to the severe irreversible membrane biofouling.

  1. Wave energy absorption by a submerged air bag connected to a rigid float

    NASA Astrophysics Data System (ADS)

    Kurniawan, A.; Chaplin, J. R.; Hann, M. R.; Greaves, D. M.; Farley, F. J. M.

    2017-04-01

    A new wave energy device features a submerged ballasted air bag connected at the top to a rigid float. Under wave action, the bag expands and contracts, creating a reciprocating air flow through a turbine between the bag and another volume housed within the float. Laboratory measurements are generally in good agreement with numerical predictions. Both show that the trajectory of possible combinations of pressure and elevation at which the device is in static equilibrium takes the shape of an S. This means that statically the device can have three different draughts, and correspondingly three different bag shapes, for the same pressure. The behaviour in waves depends on where the mean pressure-elevation condition is on the static trajectory. The captured power is highest for a mean condition on the middle section.

  2. DeepSig: deep learning improves signal peptide detection in proteins.

    PubMed

    Savojardo, Castrense; Martelli, Pier Luigi; Fariselli, Piero; Casadio, Rita

    2018-05-15

    The identification of signal peptides in protein sequences is an important step toward protein localization and function characterization. Here, we present DeepSig, an improved approach for signal peptide detection and cleavage-site prediction based on deep learning methods. Comparative benchmarks performed on an updated independent dataset of proteins show that DeepSig is the current best performing method, scoring better than other available state-of-the-art approaches on both signal peptide detection and precise cleavage-site identification. DeepSig is available as both standalone program and web server at https://deepsig.biocomp.unibo.it. All datasets used in this study can be obtained from the same website. pierluigi.martelli@unibo.it. Supplementary data are available at Bioinformatics online.

  3. Radiation release at the nation's only operating deep geological repository--an independent monitoring perspective.

    PubMed

    Thakur, P; Ballard, S; Hardy, R

    2014-11-04

    Recent incidents at the nation's only operating deep geologic nuclear waste repository, the Waste Isolation Pilot Plant (WIPP), resulted in the release of americium and plutonium from one or more defense-related transuranic (TRU) waste containers into the environment. WIPP is a U.S. Department of Energy mined geologic repository that has been in operation since March, 1999. Over 85,000 m3 of waste in various vented payload containers have been emplaced in the repository. The primary radionuclides within the disposed waste are 239+240Pu and 241Am, which account for more than 99% of the total TRU radioactivity disposed and scheduled for disposal in the repository. For the first time in its 15 years of operation, there was an airborne radiation release from the WIPP at approximately 11:30 PM Mountain Standard Time (MST) on Friday, February 14, 2014. The radiation release was likely caused by a chemical reaction inside a TRU waste drum that contained nitrate salts and organic sorbent materials. In a recent news release, DOE announced that photos taken of the waste underground showed evidence of heat and gas pressure resulting in a deformed lid, in material expelled through that deformation, and in melted plastic and rubber and polyethylene in the vicinity of that drum. Recent entries into underground Panel 7 have confirmed that at least one waste drum containing a nitrate salt bearing waste stream from Los Alamos National Laboratory was breached underground and was the most likely source of the release. Further investigation is underway to determine if other containers contributed to the release. Air monitoring across the WIPP site intensified following the first reports of radiation detection underground to ascertain whether or not there were releases to the ground surface. Independent analytical results of air filters from sampling stations on and near the WIPP facility have been released by us at the Carlsbad Environmental Monitoring & Research Center and confirmed

  4. True Triaxial Failure of Granite: Implications for Deep Borehole Waste Disposal

    NASA Astrophysics Data System (ADS)

    Williams, M.; Ingraham, M. D.; Cheung, C.; Haimson, B. C.

    2016-12-01

    A series of tests have been completed to determine the failure of Sierra White Granite under a range of true triaxial stress conditions ranging from axisymmetric compression to axisymmetric extension. Tests were performed under constant mean stress conditions. Results show a significant difference in failure due to the intermediate principal stress. Borehole breakout, a significant issue for deep borehole disposal, occurs in line with the least principal stress, which in the United States at great depth is almost certainly a horizontal stress. This means that any attempt to dispose of waste in deep boreholes will have to overcome this phenomenon. This work seeks to determine the full 3D failure surface for granite such that it can be applied to determining the likelihood of borehole breakout occurring under different stress conditions. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  5. A GIS Analysis of Seagrass Resources and Condition Within Padre Island National Seashore, Texas

    USGS Publications Warehouse

    Onuf, Christopher P.; Ingold, Jaimie J.

    2007-01-01

    A survey of the seagrass resources of Padre Island National Seashore was conducted in fall 2002 and 2003, with additional sampling through 2006, to resolve distribution questions. Location coordinates were recorded to thousandths of minutes of latitude and longitude and converted to decimal degrees (minus decimal degrees for longitude) for import into ArcView (Environmental Systems Research Institute, Inc.). The seagrass core frequency data were developed as a theme in ArcView and overlaid on digital orthophoto quarter quadrangles of the U.S. Geological Survey to show sample depth with respect to mean sea level and frequency of occurrence of seagrass for five samples collected from every station sampled. These data were used to draw boundaries of area submerged at mean sea level and seagrass meadow in relation to the boundary of Padre Island National Seashore. Frequency of seagrass occurrence, mean plant height, shoot density, plant height multiplied by shoot density, live biomass, and dead biomass on a 1' latitude by 0.25' longitude grid were collected, and their distribution was plotted in space and according to depth. A User Guide for displaying data in ArcView is included at the end of this report. Seagrasses covered almost two-thirds of the regularly flooded part of Laguna Madre within the borders of Padre Island National Seashore. Comparisons with earlier surveys showed that substantial areas of seagrass cover had been lost in deep water between 1988 and 1998 as a result of a persistent phytoplankton bloom, and little recovery has occurred since. Maximum depth of seagrass occurrence responded to changes in water clarity. In contrast, much of the cover at shallow to intermediate depths lost at the south end of the study area between 1988 and 1998 was replaced by 2003. The seven stations with greatest plant height were located in this area of recent recolonization. Continuity of cover as measured by frequency of occurrence was high except near the edge of

  6. Optimization of submerged fermentation medium for citrinin-free monascin production by Monascus.

    PubMed

    Chen, Di; Xue, Yuan; Chen, Mianhua; Li, Zhenjing; Wang, Changlu

    2016-11-16

    Microbial fermentation of citrinin-free Monascus pigments is in favor in the development of food industry. This study investigated the influences of carbon source, nitrogen source, and mineral salts on the cell growth, monascin (MS), and citrinin (CT) production in Monascus M9. A culture medium composition was established for maximizing the production of citrinin-free MS in submerged culture, as follows: 50 g/L Japonica rice powder, 20 g/L NH 4 NO 3 , 3 g/L NaNO 3 , 1.5 g/L KH 2 PO 4 , 1 g/L MgSO 4  · 7H 2 O, 0.2 g/L MnSO 4 . Under these conditions, no CT was detectable by high performance liquid chromatography. The yield of MS reached 14.11 mg/g, improving approximately 30% compared with before optimization.

  7. Survey report of NOAA Ship McArthur II cruises AR-04-04, AR-05-05 and AR-06-03: habitat classification of side scan sonar imagery in support of deep-sea coral/sponge explorations at the Olympic Coast National Marine Sanctuary

    USGS Publications Warehouse

    Intelmann, Steven S.; Cochrane, Guy R.; Bowlby, C. Edward; Brancato, Mary Sue; Hyland, Jeffrey

    2007-01-01

    Habitat mapping and characterization has been defined as a high-priority management issue for the Olympic Coast National Marine Sanctuary (OCNMS), especially for poorly known deep-sea habitats that may be sensitive to anthropogenic disturbance. As a result, a team of scientists from OCNMS, National Centers for Coastal Ocean Science (NCCOS), and other partnering institutions initiated a series of surveys to assess the distribution of deep-sea coral/sponge assemblages within the sanctuary and to look for evidence of potential anthropogenic impacts in these critical habitats. Initial results indicated that remotely delineating areas of hard bottom substrate through acoustic sensing could be a useful tool to increase the efficiency and success of subsequent ROV-based surveys of the associated deep-sea fauna. Accordingly, side scan sonar surveys were conducted in May 2004, June 2005, and April 2006 aboard the NOAA Ship McArthur II to: (1) obtain additional imagery of the seafloor for broader habitat-mapping coverage of sanctuary waters, and (2) help delineate suitable deep-sea coral-sponge habitat, in areas of both high and low commercial-fishing activities, to serve as sites for surveying-in more detail using an ROV on subsequent cruises, Several regions of the sea floor throughout the OCNMS were surveyed and mosaicked at 1-meter pixel resolution. Imagery from the side scan sonar mapping efforts was integrated with other complementary data from a towed camera sled, ROVs, sedentary samples, and bathymetry records to describe geological and biological (where possible) aspects of habitat. Using a hierarchical deep-water marine benthic classification scheme (Greene et al. 1999), we created a preliminary map of various habitat polygon features for use in a geographical information system (GIS). This report provides a description of the mapping and groundtruthing efforts as well as results of the image classification procedure for each of the areas surveyed.

  8. 76 FR 65180 - Proposed Information Collection; Comment Request; Deep Seabed Mining Exploration Licenses

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-20

    ... Collection; Comment Request; Deep Seabed Mining Exploration Licenses AGENCY: National Oceanic and Atmospheric... documentation electronically when feasible. III. Data OMB Control Number: 0648-0145. Form Number: None. Type of... information on respondents, including through the use of automated collection techniques or other forms of...

  9. The deep structure of the Sichuan basin and adjacent orogenic zones revealed by the aggregated deep seismic profiling datum

    NASA Astrophysics Data System (ADS)

    Xiong, X.; Gao, R.; Li, Q.; Wang, H.

    2012-12-01

    The sedimentary basin and the orogenic belt are the basic two tectonic units of the continental lithosphere, and form the basin-mountain coupling system, The research of which is the key element to the oil and gas exploration, the global tectonic theory and models and the development of the geological theory. The Sichuan basin and adjacent orogenic belts is one of the most ideal sites to research the issues above, in particular by the recent deep seismic profiling datum. From the 1980s to now, there are 11 deep seismic sounding profiles and 6 deep seismic reflection profiles and massive seismic broadband observation stations deployed around and crossed the Sichuan basin, which provide us a big opportunity to research the deep structure and other forward issues in this region. Supported by the National Natural Science Foundation of China (Grant No. 41104056) and the Fundamental Research Funds of the Institute of Geological Sciences, CAGS (No. J1119), we sampled the Moho depth and low-velocity zone depth and the Pn velocity of these datum, then formed the contour map of the Moho depth and Pn velocity by the interpolation of the sampled datum. The result shows the Moho depth beneath Sichuan basin ranges from 40 to 44 km, the sharp Moho offset appears in the western margin of the Sichuan basin, and there is a subtle Moho depression in the central southern part of the Sichuan basin; the P wave velocity can be 6.0 km/s at ca. 10 km deep, and increases gradually deeper, the average P wave velocity in this region is ca. 6.3 km/s; the Pn velocity is ca. 8.0-8.02 km/s in Sichuan basin, and 7.70-7.76 km/s in Chuan-Dian region; the low velocity zone appears in the western margin of the Sichuan basin, which maybe cause the cause of the earthquake.

  10. Dissipation of Electrical Energy in Submerged Arc Furnaces Producing Silicomanganese and High-Carbon Ferromanganese

    NASA Astrophysics Data System (ADS)

    Steenkamp, Joalet Dalene; Hockaday, Christopher James; Gous, Johan Petrus; Nzima, Thabo Witness

    2017-09-01

    Submerged-arc furnace technology is applied in the primary production of ferroalloys. Electrical energy is dissipated to the process via a combination of arcing and resistive heating. In processes where a crater forms between the charge zone and the reaction zone, electrical energy is dissipated mainly through arcing, e.g., in coke-bed based processes, through resistive heating. Plant-based measurements from a device called "Arcmon" indicated that in silicomanganese (SiMn) production, at times up to 15% of the electrical energy used is transferred by arcing, 30% in high-carbon ferromanganese (HCFeMn) production, compared with 5% in ferrochromium and 60% in ferrosilicon production. On average, the arcing is much less at 3% in SiMn and 5% in HCFeMn production.

  11. Eddy Seeding in the Labrador Sea: a Submerged Autonomous Launching Platform (SALP) Application

    NASA Astrophysics Data System (ADS)

    Furey, Heather H.; Femke de Jong, M.; Bower, Amy S.

    2013-04-01

    A simplified Submerged Autonomous Launch Platform (SALP) was used to release profiling floats into warm-core Irminger Rings (IRs) in order to investigate their vertical structure and evolution in the Labrador Sea from September 2007 - September 2009. IRs are thought to play an important role in restratification after convection in the Labrador Sea. The SALP is designed to release surface drifters or subsurface floats serially from a traditional ocean mooring, using real-time ocean measurements as criteria for launch. The original prototype instrument used properties measured at multiple depths, with information relayed to the SALP controller via acoustic modems. In our application, two SALP carousels were attached at 500 meters onto a heavily-instrumented deep water mooring, in the path of recently-shed IRs off the west Greenland shelf. A release algorithm was designed to use temperature and pressure measured at the SALP depth only to release one or two APEX profiling drifters each time an IR passed the mooring, using limited historical observations to set release thresholds. Mechanically and electronically, the SALP worked well: out of eleven releases, there was only one malfunction when a float was caught in the cage after the burn-wire had triggered. However, getting floats trapped in eddies met with limited success due to problems with the release algorithm and float ballasting. Out of seven floats launched from the platform using oceanographic criteria, four were released during warm water events that were not related to passing IRs. Also, after float release, it took on average about 2.6 days for the APEX to adjust from its initial ballast depth, about 600 meters, to its park point of 300 meters, leaving the float below the trapped core of water in the IRs. The other mooring instruments (at depths of 100 to 3000 m), revealed that 12 IRs passed by the mooring in the 2-year monitoring period. With this independent information, we were able to assess and improve

  12. DeepMitosis: Mitosis detection via deep detection, verification and segmentation networks.

    PubMed

    Li, Chao; Wang, Xinggang; Liu, Wenyu; Latecki, Longin Jan

    2018-04-01

    Mitotic count is a critical predictor of tumor aggressiveness in the breast cancer diagnosis. Nowadays mitosis counting is mainly performed by pathologists manually, which is extremely arduous and time-consuming. In this paper, we propose an accurate method for detecting the mitotic cells from histopathological slides using a novel multi-stage deep learning framework. Our method consists of a deep segmentation network for generating mitosis region when only a weak label is given (i.e., only the centroid pixel of mitosis is annotated), an elaborately designed deep detection network for localizing mitosis by using contextual region information, and a deep verification network for improving detection accuracy by removing false positives. We validate the proposed deep learning method on two widely used Mitosis Detection in Breast Cancer Histological Images (MITOSIS) datasets. Experimental results show that we can achieve the highest F-score on the MITOSIS dataset from ICPR 2012 grand challenge merely using the deep detection network. For the ICPR 2014 MITOSIS dataset that only provides the centroid location of mitosis, we employ the segmentation model to estimate the bounding box annotation for training the deep detection network. We also apply the verification model to eliminate some false positives produced from the detection model. By fusing scores of the detection and verification models, we achieve the state-of-the-art results. Moreover, our method is very fast with GPU computing, which makes it feasible for clinical practice. Copyright © 2018 Elsevier B.V. All rights reserved.

  13. Photometric redshifts for the CFHTLS T0004 deep and wide fields

    NASA Astrophysics Data System (ADS)

    Coupon, J.; Ilbert, O.; Kilbinger, M.; McCracken, H. J.; Mellier, Y.; Arnouts, S.; Bertin, E.; Hudelot, P.; Schultheis, M.; Le Fèvre, O.; Le Brun, V.; Guzzo, L.; Bardelli, S.; Zucca, E.; Bolzonella, M.; Garilli, B.; Zamorani, G.; Zanichelli, A.; Tresse, L.; Aussel, H.

    2009-06-01

    Aims: We compute photometric redshifts in the fourth public release of the Canada-France-Hawaii Telescope Legacy Survey. This unique multi-colour catalogue comprises u^*, g', r', i', z' photometry in four deep fields of 1 deg2 each and 35 deg2 distributed over three wide fields. Methods: We used a template-fitting method to compute photometric redshifts calibrated with a large catalogue of 16 983 high-quality spectroscopic redshifts from the VVDS-F02, VVDS-F22, DEEP2, and the zCOSMOS surveys. The method includes correction of systematic offsets, template adaptation, and the use of priors. We also separated stars from galaxies using both size and colour information. Results: Comparing with galaxy spectroscopic redshifts, we find a photometric redshift dispersion, σΔ z/(1+z_s), of 0.028-0.30 and an outlier rate, |Δ z| ≥ 0.15× (1+z_s), of 3-4% in the deep field at i'_AB < 24. In the wide fields, we find a dispersion of 0.037-0.039 and an outlier rate of 3-4% at i'_AB < 22.5. Beyond i'_AB = 22.5 in the wide fields the number of outliers rises from 5% to 10% at i'_AB < 23 and i'_AB < 24, respectively. For the wide sample the systematic redshift bias stays below 1% to i'_AB < 22.5, whereas we find no significant bias in the deep fields. We investigated the effect of tile-to-tile photometric variations and demonstrated that the accuracy of our photometric redshifts is reduced by at most 21%. Application of our star-galaxy classifier reduced the contamination by stars in our catalogues from 60% to 8% at i'_AB < 22.5 in our field with the highest stellar density while keeping a complete galaxy sample. Our CFHTLS T0004 photometric redshifts are distributed to the community. Our release includes 592891 (i'_AB < 22.5) and 244701 (i'_AB < 24) reliable galaxy photometric redshifts in the wide and deep fields, respectively. Based on observations obtained with MegaPrime/MegaCam, a joint project of CFHT and CEA/DAPNIA, at the Canada-France-Hawaii Telescope (CFHT) which is

  14. National requirements for improved elevation data

    USGS Publications Warehouse

    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

  15. Evaluating the Impact of Land Use Change on Submerged Aquatic Vegetation Stressors in Mobile Bay

    NASA Technical Reports Server (NTRS)

    Al-Hamdan, Mohammad; Estes, Maurice G., Jr.; Quattrochi, Dale; Thom, Ronald; Woodruff, Dana; Judd, Chaeli; Ellis, Jean; Watson, Brian; Rodriquez, Hugo; Johnson, Hoyt

    2009-01-01

    Alabama coastal systems have been subjected to increasing pressure from a variety of activities including urban and rural development, shoreline modifications, industrial activities, and dredging of shipping and navigation channels. The impacts on coastal ecosystems are often observed through the use of indicator species. One such indicator species for aquatic ecosystem health is submerged aquatic vegetation (SAV). Watershed and hydrodynamic modeling has been performed to evaluate the impact of land use change in Mobile and Baldwin counties on SAV stressors and controlling factors (temperature, salinity, and sediment) in Mobile Bay. Watershed modeling using the Loading Simulation Package in C++ (LSPC) was performed for all watersheds contiguous to Mobile Bay for land use scenarios in 1948, 1992, 2001, and 2030. Landsat-derived National Land Cover Data (NLCD) were used in the 1992 and 2001 simulations after having been reclassified to a common classification scheme. The Prescott Spatial Growth Model was used to project the 2030 land use scenario based on current trends. The LSPC model simulations provided output on changes in flow, temperature, and sediment for 22 discharge points into the Bay. Theses results were inputted in the Environmental Fluid Dynamics Computer Code (EFDC) hydrodynamic model to generate data on changes in temperature, salinity, and sediment on a grid with four vertical profiles throughout Mobile Bay. The changes in the aquatic ecosystem were used to perform an ecological analysis to evaluate the impact on SAV habitat suitability. This is the key product benefiting the Mobile Bay coastal environmental managers that integrates the influences of temperature, salinity, and sediment due to land use driven flow changes with the restoration potential of SAVs.

  16. Landslide-Generated Waves in a Dam Reservoir: The Effects of Landslide Rheology and Initial Submergence

    NASA Astrophysics Data System (ADS)

    Yavari Ramsheh, S.; Ataie-Ashtiani, B.

    2017-12-01

    Recent studies revealed that landslide-generated waves (LGWs) impose the largest tsunami hazard to our shorelines although earthquake-generated waves (EGWs) occur more often. Also, EGWs are commonly followed by a large number of landslide hazards. Dam reservoirs are more vulnerable to landslide events due to being located in mountainous areas. Accurate estimation of such hazards and their destructive consequences help authorities to reduce their risks by constructive measures. In this regard, a two-layer two-phase Coulomb mixture flow (2LCMFlow) model is applied to investigate the effects of landslide characteristics on LGWs for a real-sized simplification of the Maku dam reservoir, located in the North of Iran. A sensitivity analysis is performed on the role of landslide rheological and constitutive parameters and its initial submergence in LGW characteristics and formation patterns. The numerical results show that for a subaerial (SAL), a semi-submerged (SSL), and a submarine landslide (SML) with the same initial geometry, the SSLs can create the largest wave crest, up to 60% larger than SALs, for dense material. However, SMLs generally create the largest wave troughs and SALs travel the maximum runout distances beneath the water. Regarding the two-phase (solid-liquid) nature of the landslide, when interestial water is isolated from the water layer along the water/landslide interface, a LGW with up to 30% higher wave crest can be created. In this condition, increasing the pore water pressure within the granular layer results in up to 35% higher wave trough and 40% lower wave crest at the same time. These results signify the importance of appropriate description of two-phase nature and rheological behavior of landslides in accurate estimation of LGWs which demands further numerical, physical, and field studies about such phenomena.

  17. Hot, deep origin of petroleum: deep basin evidence and application

    USGS Publications Warehouse

    Price, Leigh C.

    1978-01-01

    Use of the model of a hot deep origin of oil places rigid constraints on the migration and entrapment of crude oil. Specifically, oil originating from depth migrates vertically up faults and is emplaced in traps at shallower depths. Review of petroleum-producing basins worldwide shows oil occurrence in these basins conforms to the restraints of and therefore supports the hypothesis. Most of the world's oil is found in the very deepest sedimentary basins, and production over or adjacent to the deep basin is cut by or directly updip from faults dipping into the basin deep. Generally the greater the fault throw the greater the reserves. Fault-block highs next to deep sedimentary troughs are the best target areas by the present concept. Traps along major basin-forming faults are quite prospective. The structural style of a basin governs the distribution, types, and amounts of hydrocarbons expected and hence the exploration strategy. Production in delta depocenters (Niger) is in structures cut by or updip from major growth faults, and structures not associated with such faults are barren. Production in block fault basins is on horsts next to deep sedimentary troughs (Sirte, North Sea). In basins whose sediment thickness, structure and geologic history are known to a moderate degree, the main oil occurrences can be specifically predicted by analysis of fault systems and possible hydrocarbon migration routes. Use of the concept permits the identification of significant targets which have either been downgraded or ignored in the past, such as production in or just updip from thrust belts, stratigraphic traps over the deep basin associated with major faulting, production over the basin deep, and regional stratigraphic trapping updip from established production along major fault zones.

  18. deepTools: a flexible platform for exploring deep-sequencing data.

    PubMed

    Ramírez, Fidel; Dündar, Friederike; Diehl, Sarah; Grüning, Björn A; Manke, Thomas

    2014-07-01

    We present a Galaxy based web server for processing and visualizing deeply sequenced data. The web server's core functionality consists of a suite of newly developed tools, called deepTools, that enable users with little bioinformatic background to explore the results of their sequencing experiments in a standardized setting. Users can upload pre-processed files with continuous data in standard formats and generate heatmaps and summary plots in a straight-forward, yet highly customizable manner. In addition, we offer several tools for the analysis of files containing aligned reads and enable efficient and reproducible generation of normalized coverage files. As a modular and open-source platform, deepTools can easily be expanded and customized to future demands and developments. The deepTools webserver is freely available at http://deeptools.ie-freiburg.mpg.de and is accompanied by extensive documentation and tutorials aimed at conveying the principles of deep-sequencing data analysis. The web server can be used without registration. deepTools can be installed locally either stand-alone or as part of Galaxy. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

  19. Man and the Last Great Wilderness: Human Impact on the Deep Sea

    PubMed Central

    Ramirez-Llodra, Eva; Tyler, Paul A.; Baker, Maria C.; Bergstad, Odd Aksel; Clark, Malcolm R.; Escobar, Elva; Levin, Lisa A.; Menot, Lenaick; Rowden, Ashley A.; Smith, Craig R.; Van Dover, Cindy L.

    2011-01-01

    The deep sea, the largest ecosystem on Earth and one of the least studied, harbours high biodiversity and provides a wealth of resources. Although humans have used the oceans for millennia, technological developments now allow exploitation of fisheries resources, hydrocarbons and minerals below 2000 m depth. The remoteness of the deep seafloor has promoted the disposal of residues and litter. Ocean acidification and climate change now bring a new dimension of global effects. Thus the challenges facing the deep sea are large and accelerating, providing a new imperative for the science community, industry and national and international organizations to work together to develop successful exploitation management and conservation of the deep-sea ecosystem. This paper provides scientific expert judgement and a semi-quantitative analysis of past, present and future impacts of human-related activities on global deep-sea habitats within three categories: disposal, exploitation and climate change. The analysis is the result of a Census of Marine Life – SYNDEEP workshop (September 2008). A detailed review of known impacts and their effects is provided. The analysis shows how, in recent decades, the most significant anthropogenic activities that affect the deep sea have evolved from mainly disposal (past) to exploitation (present). We predict that from now and into the future, increases in atmospheric CO2 and facets and consequences of climate change will have the most impact on deep-sea habitats and their fauna. Synergies between different anthropogenic pressures and associated effects are discussed, indicating that most synergies are related to increased atmospheric CO2 and climate change effects. We identify deep-sea ecosystems we believe are at higher risk from human impacts in the near future: benthic communities on sedimentary upper slopes, cold-water corals, canyon benthic communities and seamount pelagic and benthic communities. We finalise this review with a short

  20. Deep learning

    NASA Astrophysics Data System (ADS)

    Lecun, Yann; Bengio, Yoshua; Hinton, Geoffrey

    2015-05-01

    Deep learning allows computational models that are composed of multiple processing layers to learn representations of data with multiple levels of abstraction. These methods have dramatically improved the state-of-the-art in speech recognition, visual object recognition, object detection and many other domains such as drug discovery and genomics. Deep learning discovers intricate structure in large data sets by using the backpropagation algorithm to indicate how a machine should change its internal parameters that are used to compute the representation in each layer from the representation in the previous layer. Deep convolutional nets have brought about breakthroughs in processing images, video, speech and audio, whereas recurrent nets have shone light on sequential data such as text and speech.

  1. Deep learning.

    PubMed

    LeCun, Yann; Bengio, Yoshua; Hinton, Geoffrey

    2015-05-28

    Deep learning allows computational models that are composed of multiple processing layers to learn representations of data with multiple levels of abstraction. These methods have dramatically improved the state-of-the-art in speech recognition, visual object recognition, object detection and many other domains such as drug discovery and genomics. Deep learning discovers intricate structure in large data sets by using the backpropagation algorithm to indicate how a machine should change its internal parameters that are used to compute the representation in each layer from the representation in the previous layer. Deep convolutional nets have brought about breakthroughs in processing images, video, speech and audio, whereas recurrent nets have shone light on sequential data such as text and speech.

  2. Liquid culture production of microsclerotia and submerged conidia by Trichoderma harzianum active against damping-off disease caused by Rhizoctonia solani.

    PubMed

    Kobori, Nilce N; Mascarin, Gabriel M; Jackson, Mark A; Schisler, David A

    2015-04-01

    Media and culturing protocols were identified that supported the formation of submerged conidia and microsclerotia (MS) by Trichoderma harzianum Rifai strain T-22 using liquid culture fermentation. Liquid media with a higher carbon concentration (36 g L(-1)) promoted MS formation at all C:N ratios tested. Hyphae aggregated to form MS after 2 d growth and after 7 d MS were fully melanized. This is the first report of MS formation by T. harzianum or any species of Trichoderma. Furthermore, submerged conidia formation was induced by liquid culture media, but yields, desiccation tolerance, and storage stability varied with C:N ratio and carbon rate. Air-dried MS granules (<4% moisture) retained excellent shelf life under cool and unrefrigerated storage conditions with no loss in conidial production. A low-cost complex nitrogen source based on cottonseed flour effectively supported high MS yields. Amending potting mix with dried MS formulations reduced or eliminated damping-off of melon seedlings caused by Rhizoctonia solani. Together, the results provide insights into the liquid culture production, stabilization process, and bioefficacy of the hitherto unreported MS of T. harzianum as a potential biofungicide for use in integrated management programs against soilborne diseases. Copyright © 2014 The British Mycological Society. All rights reserved.

  3. New initiative in studies of Earth's deep interior

    NASA Astrophysics Data System (ADS)

    Lay, Thorne

    A multidisciplinary U.S. research community is undertaking a new coordinated effort to study the state and dynamics of the Earth's deep mantle and core. At an open meeting held at the Massachusetts Institute of Technology, Cambridge, from September 11 to 12, 1992, over 120 Earth scientists gathered to discuss this new program, which is an outgrowth of activity during the previous year by an ad hoc steering committee. The research program will be coordinated by a community-based scientific organization and supported through competitive research proposals submitted to the National Science Foundation with the aim of facilitating cooperative research projects cutting across traditional disciplinary and institutional boundaries.The new organization is the U.S. Studies of the Earth's Deep Interior (SEDI) Coordinating Committee. This committee will facilitate communication among the U.S. SEDI research community, federal funding agencies, the AGU Committee for Studies of the Earth's Interior (SEI), the Union SEDI Committee of the International Union of Geodesy and Geophysics, and the general public (Figure 1).

  4. Parameter optimization of flux-aided backing-submerged arc welding by using Taguchi method

    NASA Astrophysics Data System (ADS)

    Pu, Juan; Yu, Shengfu; Li, Yuanyuan

    2017-07-01

    Flux-aided backing-submerged arc welding has been conducted on D36 steel with thickness of 20 mm. The effects of processing parameters such as welding current, voltage, welding speed and groove angle on welding quality were investigated by Taguchi method. The optimal welding parameters were predicted and the individual importance of each parameter on welding quality was evaluated by examining the signal-to-noise ratio and analysis of variance (ANOVA) results. The importance order of the welding parameters for the welding quality of weld bead was: welding current > welding speed > groove angle > welding voltage. The welding quality of weld bead increased gradually with increasing welding current and welding speed and decreasing groove angle. The optimum values of the welding current, welding speed, groove angle and welding voltage were found to be 1050 A, 27 cm/min, 40∘ and 34 V, respectively.

  5. The problem of fouling in submerged membrane bioreactors - Model validation and experimental evidence

    NASA Astrophysics Data System (ADS)

    Tsibranska, Irene; Vlaev, Serafim; Tylkowski, Bartosz

    2018-01-01

    Integrating biological treatment with membrane separation has found a broad area of applications and industrial attention. Submerged membrane bioreactors (SMBRs), based on membrane modules immersed in the bioreactor, or side stream ones connected in recycle have been employed in different biotechnological processes for separation of thermally unstable products. Fouling is one of the most important challenges in the integrated SMBRs. A number of works are devoted to fouling analysis and its treatment, especially exploring the opportunity for enhanced fouling control in SMBRs. The main goal of the review is to provide a comprehensive yet concise overview of modeling the fouling in SMBRs in view of the problematics of model validation, either by real system measurements at different scales or by analysis of the obtained theoretical results. The review is focused on the current state of research applying computational fluid dynamics (CFD) modeling techniques.

  6. Discriminating a deep defect from shallow acceptors in supercell calculations: gallium antisite in GaAs

    NASA Astrophysics Data System (ADS)

    Schultz, Peter

    To make reliable first principles predictions of defect energies in semiconductors, it is crucial to discriminate between effective-mass-like defects--for which existing supercell methods fail--and deep defects--for which density functional theory calculations can yield reliable predictions of defect energy levels. The gallium antisite GaAs is often associated with the 78/203 meV shallow double acceptor in Ga-rich gallium arsenide. Within a framework of level occupation patterns, analyses of structure and spin stabilization can be used within a supercell approach to distinguish localized deep defect states from shallow acceptors such as BAs. This systematic analysis determines that the gallium antisite is inconsistent with a shallow state, and cannot be the 78/203 shallow double acceptor. The properties of the Ga antisite in GaAs are described, predicting that the Ga antisite is a deep double acceptor and has two donor states, one of which might be accidentally shallow. -- Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Company, for the U.S. Department of Energy's National Nuclear Security Administration under Contract DE-AC04-94AL85000.

  7. Deep learning in bioinformatics.

    PubMed

    Min, Seonwoo; Lee, Byunghan; Yoon, Sungroh

    2017-09-01

    In the era of big data, transformation of biomedical big data into valuable knowledge has been one of the most important challenges in bioinformatics. Deep learning has advanced rapidly since the early 2000s and now demonstrates state-of-the-art performance in various fields. Accordingly, application of deep learning in bioinformatics to gain insight from data has been emphasized in both academia and industry. Here, we review deep learning in bioinformatics, presenting examples of current research. To provide a useful and comprehensive perspective, we categorize research both by the bioinformatics domain (i.e. omics, biomedical imaging, biomedical signal processing) and deep learning architecture (i.e. deep neural networks, convolutional neural networks, recurrent neural networks, emergent architectures) and present brief descriptions of each study. Additionally, we discuss theoretical and practical issues of deep learning in bioinformatics and suggest future research directions. We believe that this review will provide valuable insights and serve as a starting point for researchers to apply deep learning approaches in their bioinformatics studies. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  8. Structured-Light Based 3d Laser Scanning of Semi-Submerged Structures

    NASA Astrophysics Data System (ADS)

    van der Lucht, J.; Bleier, M.; Leutert, F.; Schilling, K.; Nüchter, A.

    2018-05-01

    In this work we look at 3D acquisition of semi-submerged structures with a triangulation based underwater laser scanning system. The motivation is that we want to simultaneously capture data above and below water to create a consistent model without any gaps. The employed structured light scanner consist of a machine vision camera and a green line laser. In order to reconstruct precise surface models of the object it is necessary to model and correct for the refraction of the laser line and camera rays at the water-air boundary. We derive a geometric model for the refraction at the air-water interface and propose a method for correcting the scans. Furthermore, we show how the water surface is directly estimated from sensor data. The approach is verified using scans captured with an industrial manipulator to achieve reproducible scanner trajectories with different incident angles. We show that the proposed method is effective for refractive correction and that it can be applied directly to the raw sensor data without requiring any external markers or targets.

  9. Navigating environmental, economic, and technological trade-offs in the design and operation of submerged anaerobic membrane bioreactors (AnMBRs).

    PubMed

    Pretel, R; Shoener, B D; Ferrer, J; Guest, J S

    2015-12-15

    Anaerobic membrane bioreactors (AnMBRs) enable energy recovery from wastewater while simultaneously achieving high levels of treatment. The objective of this study was to elucidate how detailed design and operational decisions of submerged AnMBRs influence the technological, environmental, and economic sustainability of the system across its life cycle. Specific design and operational decisions evaluated included: solids retention time (SRT), mixed liquor suspended solids (MLSS) concentration, sludge recycling ratio (r), flux (J), and specific gas demand per membrane area (SGD). The possibility of methane recovery (both as biogas and as soluble methane in reactor effluent) and bioenergy production, nutrient recovery, and final destination of the sludge (land application, landfill, or incineration) were also evaluated. The implications of these design and operational decisions were characterized by leveraging a quantitative sustainable design (QSD) framework which integrated steady-state performance modeling across seasonal temperatures (using pilot-scale experimental data and the simulating software DESASS), life cycle cost (LCC) analysis, and life cycle assessment (LCA). Sensitivity and uncertainty analyses were used to characterize the relative importance of individual design decisions, and to navigate trade-offs across environmental, economic, and technological criteria. Based on this analysis, there are design and operational conditions under which submerged AnMBRs could be net energy positive and contribute to the pursuit of carbon negative wastewater treatment. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Soft tissue decomposition of submerged, dismembered pig limbs enclosed in plastic bags.

    PubMed

    Pakosh, Caitlin M; Rogers, Tracy L

    2009-11-01

    This study examines underwater soft tissue decomposition of dismembered pig limbs deposited in polyethylene plastic bags. The research evaluates the level of influence that disposal method has on underwater decomposition processes and details observations specific to this scenario. To our knowledge, no other study has yet investigated decomposing, dismembered, and enclosed remains in water environments. The total sample size consisted of 120 dismembered pig limbs, divided into a subsample of 30 pig limbs per recovery period (34 and 71 days) for each treatment. The two treatments simulated non-enclosed and plastic enclosed disposal methods in a water context. The remains were completely submerged in Lake Ontario for 34 and 71 days. In both recovery periods, the non-enclosed samples lost soft tissue to a significantly greater extent than their plastic enclosed counterparts. Disposal of remains in plastic bags therefore results in preservation, most likely caused by bacterial inhibition and reduced oxygen levels.

  11. Performance assessment of a submerged membrane bioreactor using a novel microbial consortium.

    PubMed

    Chon, Kangmin; Lee, Kyungpyo; Kim, In-Soo; Jang, Am

    2016-06-01

    The performance of a submerged membrane bioreactor (MBR) with and without a novel microbial consortium (NMBR vs. CMBR) was compared to provide deeper insights into the effects of changes in water quality and dissolved organic matter (DOM) characteristics by a novel microbial consortium on the fouling characteristics of MBR processes. Despite similar operating conditions and identical DOM properties in the feed waters, NMBR exhibited a lower propensity to release polysaccharide-like compounds with low molecular weight by bacterial activities compared to CMBR. These compounds have a great fouling potential for MBR processes. Therefore, an increase in the transmembrane pressure (TMP) of NMBR (normalized TMP (TMP/TMP0): 1.14) was much slower and less significant than that observed in CMBR (TMP/TMP0: 2.61). These observations imply that the novel microbial consortium can efficiently mitigate membrane fouling by hydrophilic DOM in MBR processes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Estimation of Leaf Area Index and Plant Area Index of a Submerged Macrophyte Canopy Using Digital Photography

    PubMed Central

    Zhao, Dehua; Xie, Dong; Zhou, Hengjie; Jiang, Hao; An, Shuqing

    2012-01-01

    Non-destructive estimation using digital cameras is a common approach for estimating leaf area index (LAI) of terrestrial vegetation. However, no attempt has been made so far to develop non-destructive approaches to LAI estimation for aquatic vegetation. Using the submerged plant species Potamogeton malainus, the objective of this study was to determine whether the gap fraction derived from vertical photographs could be used to estimate LAI of aquatic vegetation. Our results suggested that upward-oriented photographs taken from beneath the water surface were more suitable for distinguishing vegetation from other objects than were downward-oriented photographs taken from above the water surface. Exposure settings had a substantial influence on the identification of vegetation in upward-oriented photographs. Automatic exposure performed nearly as well as the optimal trial exposure, making it a good choice for operational convenience. Similar to terrestrial vegetation, our results suggested that photographs taken for the purpose of distinguishing gap fraction in aquatic vegetation should be taken under diffuse light conditions. Significant logarithmic relationships were observed between the vertical gap fraction derived from upward-oriented photographs and plant area index (PAI) and LAI derived from destructive harvesting. The model we developed to depict the relationship between PAI and gap fraction was similar to the modified theoretical Poisson model, with coefficients of 1.82 and 1.90 for our model and the theoretical model, respectively. This suggests that vertical upward-oriented photographs taken from below the water surface are a feasible alternative to destructive harvesting for estimating PAI and LAI for the submerged aquatic plant Potamogeton malainus. PMID:23226557

  13. National Grid Deep Energy Retrofit Pilot Program—Clark Residence

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

    2010-03-30

    In this case study, Building Science Corporation partnered with local utility company, National Grid, Massachusetts homes. This project involved the renovation of a 18th century Cape-style building and achieved a super-insulated enclosure (R-35 walls, R-50+ roof, R-20+ foundation), extensive water management improvements, high-efficiency water heater, and state-of-the-art ventilation.

  14. Cyriax's deep friction massage application parameters: Evidence from a cross-sectional study with physiotherapists.

    PubMed

    Chaves, Paula; Simões, Daniela; Paço, Maria; Pinho, Francisco; Duarte, José Alberto; Ribeiro, Fernando

    2017-12-01

    Deep friction massage is one of several physiotherapy interventions suggested for the management of tendinopathy. To determine the prevalence of deep friction massage use in clinical practice, to characterize the application parameters used by physiotherapists, and to identify empirical model-based patterns of deep friction massage application in degenerative tendinopathy. observational, analytical, cross-sectional and national web-based survey. 478 physiotherapists were selected through snow-ball sampling method. The participants completed an online questionnaire about personal and professional characteristics as well as specific questions regarding the use of deep friction massage. Characterization of deep friction massage parameters used by physiotherapists were presented as counts and proportions. Latent class analysis was used to identify the empirical model-based patterns. Crude and adjusted odds ratios and 95% confidence intervals were computed. The use of deep friction massage was reported by 88.1% of the participants; tendinopathy was the clinical condition where it was most frequently used (84.9%) and, from these, 55.9% reported its use in degenerative tendinopathy. The "duration of application" parameters in chronic phase and "frequency of application" in acute and chronic phases are those that diverge most from those recommended by the author of deep friction massage. We found a high prevalence of deep friction massage use, namely in degenerative tendinopathy. Our results have shown that the application parameters are heterogeneous and diverse. This is reflected by the identification of two application patterns, although none is in complete agreement with Cyriax's description. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Neutrino-Nucleon Deep Inelastic Scattering in MINERvA

    NASA Astrophysics Data System (ADS)

    Norrick, Anne; Minerva Collaboration

    2015-04-01

    Neutrino-Nucleon Deep Inelastic Scattering (DIS) events provide a probe into the structure of the nucleus that cannot be accessed via charged lepton-nucleon interactions. The MINERvA experiment is stationed in the Neutrinos from the Main Injector (NuMI) beam line at Fermi National Accelerator Laboratory. The projected sensitivity of nuclear structure function analyses using MINERvA's suite of nuclear targets (C, CH, Fe and Pb) in the upgraded 6 GeV neutrino energy NuMI beam will be explored, and their impact discussed.

  16. System Certification Procedures and Criteria Manual for Deep Submergence Systems

    DTIC Science & Technology

    1973-07-01

    Certification Milestone Events. The applicant and SCA interplay and negotiations between milestones is stressed . Effective and frequent communication...a series of events beginning with a single failure, often relatively minor, which may place the DSq Personnel or equipments under additional stresses ...for the particular DSS. p. Support ship handling system components such as cranes , brakes, and cables when the DSS is handled with personnel aboard. q

  17. U.S. National Committee for Geochemistry

    ERIC Educational Resources Information Center

    Geotimes, 1974

    1974-01-01

    Reports highlights of the April, 1973 meeting of the U.S. National Committee for Geochemistry. Some of the topics reported on were: The Geophysics Research Board, deep drilling, exchange of geochemists with China and the activities of the Subcommittee on Geochemical Environment in Relation to Health and Disease. (BR)

  18. The Greening after Extended Darkness1 Is an N-End Rule Pathway Mutant with High Tolerance to Submergence and Starvation1[OPEN

    PubMed Central

    Riber, Willi; Müller, Jana T.; Visser, Eric J.W.; Sasidharan, Rashmi; Voesenek, Laurentius A.C.J.; Mustroph, Angelika

    2015-01-01

    Plants respond to reductions in internal oxygen concentrations with adaptive mechanisms (for example, modifications of metabolism to cope with reduced supply of ATP). These responses are, at the transcriptional level, mediated by the group VII Ethylene Response Factor transcription factors, which have stability that is regulated by the N-end rule pathway of protein degradation. N-end rule pathway mutants are characterized by a constitutive expression of hypoxia response genes and abscisic acid hypersensitivity. Here, we identify a novel proteolysis6 (prt6) mutant allele, named greening after extended darkness1 (ged1), which was previously discovered in a screen for genomes uncoupled-like mutants and shows the ability to withstand long periods of darkness at the seedling stage. Interestingly, this ethyl methanesulfonate-derived mutant shows unusual chromosomal rearrangement instead of a point mutation. Furthermore, the sensitivity of N-end rule pathway mutants ged1 and prt6-1 to submergence was studied in more detail to understand previously contradicting experiments on this topic. Finally, it was shown that mutants for the N-end rule pathway are generally more tolerant to starvation conditions, such as prolonged darkness or submergence, which was partially associated with carbohydrate conservation. PMID:25667318

  19. Generation Mechanism and Prediction Model for Low Frequency Noise Induced by Energy Dissipating Submerged Jets during Flood Discharge from a High Dam

    PubMed Central

    Lian, Jijian; Zhang, Wenjiao; Guo, Qizhong; Liu, Fang

    2016-01-01

    As flood water is discharged from a high dam, low frequency (i.e., lower than 10 Hz) noise (LFN) associated with air pulsation is generated and propagated in the surrounding areas, causing environmental problems such as vibrations of windows and doors and discomfort of residents and construction workers. To study the generation mechanisms and key influencing factors of LFN induced by energy dissipation through submerged jets at a high dam, detailed prototype observations and analyses of LFN are conducted. The discharge flow field is simulated using a gas-liquid turbulent flow model, and the vorticity fluctuation characteristics are then analyzed. The mathematical model for the LFN intensity is developed based on vortex sound theory and a turbulent flow model, verified by prototype observations. The model results reveal that the vorticity fluctuation in strong shear layers around the high-velocity submerged jets is highly correlated with the on-site LFN, and the strong shear layers are the main regions of acoustic source for the LFN. In addition, the predicted and observed magnitudes of LFN intensity agree quite well. This is the first time that the LFN intensity has been shown to be able to be predicted quantitatively. PMID:27314374

  20. LUNA: Nuclear Astrophysics Deep Underground

    NASA Astrophysics Data System (ADS)

    Broggini, Carlo; Bemmerer, Daniel; Guglielmetti, Alessandra; Menegazzo, Roberto

    2010-11-01

    Nuclear astrophysics strives for a comprehensive picture of the nuclear reactions responsible for synthesizing chemical elements and for powering the stellar evolution engine. Deep underground in the Gran Sasso National Laboratory, the cross sections of the key reactions of the proton-proton chain and of the carbon-nitrogen-oxygen cycle have been measured right down to the energies of astrophysical interest. The salient features of underground nuclear astrophysics are summarized here. We review the main results obtained by LUNA during the past 20 years and discuss their influence on our understanding of the properties of the neutrino, the Sun, and the universe itself. Future directions of underground nuclear astrophysics toward the study both of helium and carbon burning and of stellar neutron sources in stars are outlined.

  1. The formation of Greenland Sea Deep Water: double diffusion or deep convection?

    NASA Astrophysics Data System (ADS)

    Clarke, R. Allyn; Swift, James H.; Reid, Joseph L.; Koltermann, K. Peter

    1990-09-01

    An examination of the extensive hydrographic data sets collected by C.S.S. Hudson and F.S. Meteor in the Norwegian and Greenland Seas during February-June 1982 reveals property distributions and circulation patterns broadly similar to those seen in earlier data sets. These data sets, however, reveal the even stronger role played by topography, with evidence of separate circulation patterns and separate water masses in each of the deep basins. The high precision temperature, salinity and oxygen data obtained reveals significant differences in the deep and bottom waters found in the various basins of the Norwegian and Greenland Seas. A comparison of the 1982 data set with earlier sets shows that the renewal of Greenland Sea Deep Water must have taken place sometime over the last decade; however there is no evidence that deep convective renewal of any of the deep and bottom waters in this region was taking place at the time of the observations. The large-scale density fields, however, do suggest that deep convection to the bottom is most likely to occure in the Greenland Basin due to its deep cyclonic circulation. The hypothesis that Greenland Sea Deep Water (GSDW) is formed through dipycnal mixing processes acting on the warm salty core of Atlantic Water entering the Greenland Sea is examined. θ-S correlations and oxygen concentrations suggest that the salinity maxima in the Greenland Sea are the product of at least two separate mixing processes, not the hypothesized single mixing process leading to GSDW. A simple one-dimensional mixed layer model with ice growth and decay demonstrates that convective renewal of GSDW would have occurred within the Greenland Sea had the winter been a little more severe. The new GSDW produced would have only 0.003 less salt and less than 0.04 ml 1 -1 greater oxygen concentration than that already in the basin. Consequently, detection of whether new deep water has been produced following a winter cooling season could be difficult even

  2. Deep subsurface microbial processes

    USGS Publications Warehouse

    Lovley, D.R.; Chapelle, F.H.

    1995-01-01

    Information on the microbiology of the deep subsurface is necessary in order to understand the factors controlling the rate and extent of the microbially catalyzed redox reactions that influence the geophysical properties of these environments. Furthermore, there is an increasing threat that deep aquifers, an important drinking water resource, may be contaminated by man's activities, and there is a need to predict the extent to which microbial activity may remediate such contamination. Metabolically active microorganisms can be recovered from a diversity of deep subsurface environments. The available evidence suggests that these microorganisms are responsible for catalyzing the oxidation of organic matter coupled to a variety of electron acceptors just as microorganisms do in surface sediments, but at much slower rates. The technical difficulties in aseptically sampling deep subsurface sediments and the fact that microbial processes in laboratory incubations of deep subsurface material often do not mimic in situ processes frequently necessitate that microbial activity in the deep subsurface be inferred through nonmicrobiological analyses of ground water. These approaches include measurements of dissolved H2, which can predict the predominant microbially catalyzed redox reactions in aquifers, as well as geochemical and groundwater flow modeling, which can be used to estimate the rates of microbial processes. Microorganisms recovered from the deep subsurface have the potential to affect the fate of toxic organics and inorganic contaminants in groundwater. Microbial activity also greatly influences 1 the chemistry of many pristine groundwaters and contributes to such phenomena as porosity development in carbonate aquifers, accumulation of undesirably high concentrations of dissolved iron, and production of methane and hydrogen sulfide. Although the last decade has seen a dramatic increase in interest in deep subsurface microbiology, in comparison with the study of

  3. Do deep convolutional neural networks really need to be deep when applied for remote scene classification?

    NASA Astrophysics Data System (ADS)

    Luo, Chang; Wang, Jie; Feng, Gang; Xu, Suhui; Wang, Shiqiang

    2017-10-01

    Deep convolutional neural networks (CNNs) have been widely used to obtain high-level representation in various computer vision tasks. However, for remote scene classification, there are not sufficient images to train a very deep CNN from scratch. From two viewpoints of generalization power, we propose two promising kinds of deep CNNs for remote scenes and try to find whether deep CNNs need to be deep for remote scene classification. First, we transfer successful pretrained deep CNNs to remote scenes based on the theory that depth of CNNs brings the generalization power by learning available hypothesis for finite data samples. Second, according to the opposite viewpoint that generalization power of deep CNNs comes from massive memorization and shallow CNNs with enough neural nodes have perfect finite sample expressivity, we design a lightweight deep CNN (LDCNN) for remote scene classification. With five well-known pretrained deep CNNs, experimental results on two independent remote-sensing datasets demonstrate that transferred deep CNNs can achieve state-of-the-art results in an unsupervised setting. However, because of its shallow architecture, LDCNN cannot obtain satisfactory performance, regardless of whether in an unsupervised, semisupervised, or supervised setting. CNNs really need depth to obtain general features for remote scenes. This paper also provides baseline for applying deep CNNs to other remote sensing tasks.

  4. Bacterial Activity and Geochemical Reactions in Submerged Cave Development -- Impact on Karst Aquifers in Florida

    NASA Astrophysics Data System (ADS)

    Herman, J. S.; Franklin, R. B.; Mills, A. L.; Giannotti, A. L.; Tysall, T. N.

    2008-05-01

    Elucidation of coupled mechanisms of sulfide oxidation and biomass generation supports an improved understanding the driving forces behind acid production, calcite dissolution, cave development, and karst aquifers characterization. Wekiwa Springs Cave and DeLeon Springs Cave, located in central Florida, both contain prolific bacterial mats from which sulfur-oxidizing bacteria have been identified. Wekiwa Springs Cave, a submerged cave developed in the Hawthorne Formation and located near Orlando, Florida, has groundwater discharge from the Floridian aquifer system, with some contribution from surficial and intermediate aquifers. The spring is the headwater of the Wekiwa River and releases a total of 170,000 m3 of water per day. The ceiling and walls are heavily covered (10 cm thick) with three morphologically distinct types of microbial mats largely comprising sulfur-oxidizing bacteria. Analysis of nearby groundwater collected from wells confirms sulfide concentrations in the regional groundwater of ~ 1.5 mg/L, though sulfide concentrations for water collected in the cave are below detection. Dissolved oxygen concentration in the water is low (<0.5 mg/L). DeLeon Springs Cave, a submerged cave located in Volusia County, Florida, is a single conduit with an average discharge of ~ 70,000 m3 of water per day, and water chemistry data suggest the presence of a saline seep in the system. Dense microbial mats cover the rock surfaces of the cave; the mats are highly filamentous, with long white streamers that often extend 1-2 feet from the cave wall. Microscopic analysis has confirmed the presence of sulfur granules within these bacterial cells, similar to those observed in the Wekiwa cave organisms. The water chemistry in DeLeon Springs Cave, however, is distinct from that of Wekiwa Springs Cave. Though DO, Fetotal, and HS- values are similar for the two sites, the concentration of ions such as Cl-, Na+, and SO42- are considerably higher at DeLeon. A similar contrast

  5. DeepSurv: personalized treatment recommender system using a Cox proportional hazards deep neural network.

    PubMed

    Katzman, Jared L; Shaham, Uri; Cloninger, Alexander; Bates, Jonathan; Jiang, Tingting; Kluger, Yuval

    2018-02-26

    Medical practitioners use survival models to explore and understand the relationships between patients' covariates (e.g. clinical and genetic features) and the effectiveness of various treatment options. Standard survival models like the linear Cox proportional hazards model require extensive feature engineering or prior medical knowledge to model treatment interaction at an individual level. While nonlinear survival methods, such as neural networks and survival forests, can inherently model these high-level interaction terms, they have yet to be shown as effective treatment recommender systems. We introduce DeepSurv, a Cox proportional hazards deep neural network and state-of-the-art survival method for modeling interactions between a patient's covariates and treatment effectiveness in order to provide personalized treatment recommendations. We perform a number of experiments training DeepSurv on simulated and real survival data. We demonstrate that DeepSurv performs as well as or better than other state-of-the-art survival models and validate that DeepSurv successfully models increasingly complex relationships between a patient's covariates and their risk of failure. We then show how DeepSurv models the relationship between a patient's features and effectiveness of different treatment options to show how DeepSurv can be used to provide individual treatment recommendations. Finally, we train DeepSurv on real clinical studies to demonstrate how it's personalized treatment recommendations would increase the survival time of a set of patients. The predictive and modeling capabilities of DeepSurv will enable medical researchers to use deep neural networks as a tool in their exploration, understanding, and prediction of the effects of a patient's characteristics on their risk of failure.

  6. Pathogenesis of deep endometriosis.

    PubMed

    Gordts, Stephan; Koninckx, Philippe; Brosens, Ivo

    2017-12-01

    The pathophysiology of (deep) endometriosis is still unclear. As originally suggested by Cullen, change the definition "deeper than 5 mm" to "adenomyosis externa." With the discovery of the old European literature on uterine bleeding in 5%-10% of the neonates and histologic evidence that the bleeding represents decidual shedding, it is postulated/hypothesized that endometrial stem/progenitor cells, implanted in the pelvic cavity after birth, may be at the origin of adolescent and even the occasionally premenarcheal pelvic endometriosis. Endometriosis in the adolescent is characterized by angiogenic and hemorrhagic peritoneal and ovarian lesions. The development of deep endometriosis at a later age suggests that deep infiltrating endometriosis is a delayed stage of endometriosis. Another hypothesis is that the endometriotic cell has undergone genetic or epigenetic changes and those specific changes determine the development into deep endometriosis. This is compatible with the hereditary aspects, and with the clonality of deep and cystic ovarian endometriosis. It explains the predisposition and an eventual causal effect by dioxin or radiation. Specific genetic/epigenetic changes could explain the various expressions and thus typical, cystic, and deep endometriosis become three different diseases. Subtle lesions are not a disease until epi(genetic) changes occur. A classification should reflect that deep endometriosis is a specific disease. In conclusion the pathophysiology of deep endometriosis remains debated and the mechanisms of disease progression, as well as the role of genetics and epigenetics in the process, still needs to be unraveled. Copyright © 2017 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  7. Detection of Emerging Vaccine-Related Polioviruses by Deep Sequencing.

    PubMed

    Sahoo, Malaya K; Holubar, Marisa; Huang, ChunHong; Mohamed-Hadley, Alisha; Liu, Yuanyuan; Waggoner, Jesse J; Troy, Stephanie B; Garcia-Garcia, Lourdes; Ferreyra-Reyes, Leticia; Maldonado, Yvonne; Pinsky, Benjamin A

    2017-07-01

    Oral poliovirus vaccine can mutate to regain neurovirulence. To date, evaluation of these mutations has been performed primarily on culture-enriched isolates by using conventional Sanger sequencing. We therefore developed a culture-independent, deep-sequencing method targeting the 5' untranslated region (UTR) and P1 genomic region to characterize vaccine-related poliovirus variants. Error analysis of the deep-sequencing method demonstrated reliable detection of poliovirus mutations at levels of <1%, depending on read depth. Sequencing of viral nucleic acids from the stool of vaccinated, asymptomatic children and their close contacts collected during a prospective cohort study in Veracruz, Mexico, revealed no vaccine-derived polioviruses. This was expected given that the longest duration between sequenced sample collection and the end of the most recent national immunization week was 66 days. However, we identified many low-level variants (<5%) distributed across the 5' UTR and P1 genomic region in all three Sabin serotypes, as well as vaccine-related viruses with multiple canonical mutations associated with phenotypic reversion present at high levels (>90%). These results suggest that monitoring emerging vaccine-related poliovirus variants by deep sequencing may aid in the poliovirus endgame and efforts to ensure global polio eradication. Copyright © 2017 Sahoo et al.

  8. Introducing Deep Underground Science to Middle Schoolers: Challenges and Rewards

    NASA Astrophysics Data System (ADS)

    McMahan Norris, Margaret

    2010-03-01

    Work is in progress to define the mission, vision, scope and preliminary design of the Sanford Center for Science Education (SCSE), the education arm of the Deep Underground Science and Engineering Laboratory (DUSEL), a proposed major research facility of the National Science Foundation. If final funding is approved, DUSEL will be built at the site of the former Homestake Gold Mine in Lead, South Dakota beginning in 2012. The SCSE is envisioned to serve as a model for the integration of a science education center into the fabric of a new national laboratory. Its broad mission is to share the excitement and promise of deep underground science and engineering at Homestake with learners of all ages worldwide. The science to be pursued at DUSEL, whether in physics, astronomy, geomicrobiology, or geoscience, is transformational and sparks the imagination of learners of all ages. While the SCSE is under design, an early education program has been initiated that is designed to build capacity for the envisioned center, to prototype individual programs, and to build partnerships and community support. This talk will give an overview of the middle school portion of that program and its context within the overall content development plan of the SCSE.

  9. Monitoring structural response in pressurized environments. Part 2: Applications

    NASA Astrophysics Data System (ADS)

    Roach, D. P.

    There are various methods which can be used to monitor the structural response of electrical components, weapon systems, pressure vessels, submerged pipelines, deep sea vehicles and offshore structures. Numerous experimental techniques have been developed at Sandia National Labs in order to measure the strain, displacement and acceleration of a structural member. These techniques have been successfully implemented in adverse environments of 25 ksi and 300 F. A separate paper discusses the performance of various instrumentation schemes, the environmental protection of these diagnostics under pressure, and the means by which data is extracted from a closed pressure system. In this paper, specific hydrostatic and dynamic pressure tests are used to demonstrate how these techniques are employed, the problems encountered, and the importance of the data obtained.

  10. Light and transmission electron microscopy of the intact interfaces between non-submerged titanium-coated epoxy resin implants and bone or gingiva.

    PubMed

    Listgarten, M A; Buser, D; Steinemann, S G; Donath, K; Lang, N P; Weber, H P

    1992-02-01

    This experiment was aimed at studying the intact tissue/implant interface of non-submerged dental implants with a titanium surface. Epoxy-resin replicas were fabricated from 3.05 x 8 mm cylindrical titanium implants with a plasma-sprayed apical portion and a smooth coronal collar. The replicas were coated with a 90-120-nm-thick layer of pure titanium and autoclaved. The coated replicas were inserted as non-submerged endosseous implants in the edentulous premolar region of dog mandibles and allowed to heal for three months. Jaw sections containing the implants were processed for light and electron microscopic study of the intact tissue/implant interface with and without prior demineralization. Gingival connective tissue fibers were closely adapted to the titanium layer, in an orientation more or less parallel to the implant surface. There was no evidence of any fiber insertions into the surface irregularities of the smooth or rough titanium surface. Undemineralized bone was intimately adapted to the titanium surface without any intervening space. In demineralized sections, the collagen fibers of the bone matrix tended to be somewhat thinner and occasionally less densely packed in the vicinity of the implant surface. However, they extended all the way to the titanium surface, without any intervening fibril-free layer.

  11. 76 FR 24923 - National Science Board; Sunshine Act Meetings; Notice

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-03

    ...: Some portions open, some portions closed. UPDATES: Please refer to the National Science Board Web site... Information Item: Status Deep Underground Science and Engineering Laboratory Information Item: High...

  12. Dining in the Deep: The Feeding Ecology of Deep-Sea Fishes

    NASA Astrophysics Data System (ADS)

    Drazen, Jeffrey C.; Sutton, Tracey T.

    2017-01-01

    Deep-sea fishes inhabit ˜75% of the biosphere and are a critical part of deep-sea food webs. Diet analysis and more recent trophic biomarker approaches, such as stable isotopes and fatty-acid profiles, have enabled the description of feeding guilds and an increased recognition of the vertical connectivity in food webs in a whole-water-column sense, including benthic-pelagic coupling. Ecosystem modeling requires data on feeding rates; the available estimates indicate that deep-sea fishes have lower per-individual feeding rates than coastal and epipelagic fishes, but the overall predation impact may be high. A limited number of studies have measured the vertical flux of carbon by mesopelagic fishes, which appears to be substantial. Anthropogenic activities are altering deep-sea ecosystems and their services, which are mediated by trophic interactions. We also summarize outstanding data gaps.

  13. Religious Conflicts and Education in Nigeria: Implications for National Security

    ERIC Educational Resources Information Center

    Ushe, Ushe Mike

    2015-01-01

    The persistent religious conflicts and insecurity in Nigeria has given meaningful Nigerians a cause for deep concern in recent times. Many of them wonder why religion which used to be the cohesive factor and core of national unity, peaceful co-existence and national development has become a tool for political manipulation, violence, destruction of…

  14. DeepARG: a deep learning approach for predicting antibiotic resistance genes from metagenomic data.

    PubMed

    Arango-Argoty, Gustavo; Garner, Emily; Pruden, Amy; Heath, Lenwood S; Vikesland, Peter; Zhang, Liqing

    2018-02-01

    Growing concerns about increasing rates of antibiotic resistance call for expanded and comprehensive global monitoring. Advancing methods for monitoring of environmental media (e.g., wastewater, agricultural waste, food, and water) is especially needed for identifying potential resources of novel antibiotic resistance genes (ARGs), hot spots for gene exchange, and as pathways for the spread of ARGs and human exposure. Next-generation sequencing now enables direct access and profiling of the total metagenomic DNA pool, where ARGs are typically identified or predicted based on the "best hits" of sequence searches against existing databases. Unfortunately, this approach produces a high rate of false negatives. To address such limitations, we propose here a deep learning approach, taking into account a dissimilarity matrix created using all known categories of ARGs. Two deep learning models, DeepARG-SS and DeepARG-LS, were constructed for short read sequences and full gene length sequences, respectively. Evaluation of the deep learning models over 30 antibiotic resistance categories demonstrates that the DeepARG models can predict ARGs with both high precision (> 0.97) and recall (> 0.90). The models displayed an advantage over the typical best hit approach, yielding consistently lower false negative rates and thus higher overall recall (> 0.9). As more data become available for under-represented ARG categories, the DeepARG models' performance can be expected to be further enhanced due to the nature of the underlying neural networks. Our newly developed ARG database, DeepARG-DB, encompasses ARGs predicted with a high degree of confidence and extensive manual inspection, greatly expanding current ARG repositories. The deep learning models developed here offer more accurate antimicrobial resistance annotation relative to current bioinformatics practice. DeepARG does not require strict cutoffs, which enables identification of a much broader diversity of ARGs. The

  15. Multiple mitigation mechanisms: Effects of submerged plants on the toxicity of nine insecticides to aquatic animals.

    PubMed

    Brogan, William R; Relyea, Rick A

    2017-01-01

    Understanding the processes that regulate contaminant impacts in nature is an increasingly important challenge. For insecticides in surface waters, the ability of aquatic plants to sorb, or bind, hydrophobic compounds has been identified as a primary mechanism by which toxicity can be mitigated (i.e. the sorption-based model). However, recent research shows that submerged plants can also rapidly mitigate the toxicity of the less hydrophobic insecticide malathion via alkaline hydrolysis (i.e. the hydrolysis-based model) driven by increased water pH resulting from photosynthesis. However, it is still unknown how generalizable these mitigation mechanisms are across the wide variety of insecticides applied today, and whether any general rules can be ascertained about which types of chemicals may be mitigated by each mechanism. We quantified the degree to which the submerged plant Elodea canadensis mitigated acute (48-h) toxicity to Daphnia magna using nine commonly applied insecticides spanning three chemical classes (carbamates: aldicarb, carbaryl, carbofuran; organophosphates: malathion, diazinon, chlorpyrifos; pyrethroids: permethrin, bifenthrin, lambda-cyhalothrin). We found that insecticides possessing either high octanol-water partition coefficients (log K ow ) values (i.e. pyrethroids) or high susceptibility to alkaline hydrolysis (i.e. carbamates and malathion) were all mitigated to some degree by E. canadensis, while the plant had no effect on insecticides possessing intermediate log K ow values and low susceptibility to hydrolysis (i.e. chlorpyrifos and diazinon). Our results provide the first general insights into which types of insecticides are likely to be mitigated by different mechanisms based on known chemical properties. We suggest that current models and mitigation strategies would be improved by the consideration of both mitigation models. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Measuring landscape-scale spread and persistence of an invaded submerged plant community from airborne remote sensing.

    PubMed

    Santos, Maria J; Khanna, Shruti; Hestir, Erin L; Greenberg, Jonathan A; Ustin, Susan L

    2016-09-01

    Processes of spread and patterns of persistence of invasive species affect species and communities in the new environment. Predicting future rates of spread is of great interest for timely management decisions, but this depends on models that rely on understanding the processes of invasion and historic observations of spread and persistence. Unfortunately, the rates of spread and patterns of persistence are difficult to model or directly observe, especially when multiple rates of spread and diverse persistence patterns may be co-occurring over the geographic distribution of the invaded ecosystem. Remote sensing systematically acquires data over large areas at fine spatial and spectral resolutions over multiple time periods that can be used to quantify spread processes and persistence patterns. We used airborne imaging spectroscopy data acquired once a year for 5 years from 2004 to 2008 to map an invaded submerged aquatic vegetation (SAV) community across 2220 km 2 of waterways in the Sacramento-San Joaquin River Delta, California, USA, and measured its spread rate and its persistence. Submerged aquatic vegetation covered 13-23 km 2 of the waterways (6-11%) every year. Yearly new growth accounted for 40-60% of the SAV area, ~50% of which survived to following year. Spread rates were overall negative and persistence decreased with time. From this dataset, we were able to identify both radial and saltatorial spread of the invaded SAV in the entire extent of the Delta over time. With both decreasing spread rate and persistence, it is possible that over time the invasion of this SAV community could decrease its ecological impact. A landscape-scale approach allows measurements of all invasion fronts and the spatial anisotropies associated with spread processes and persistence patterns, without spatial interpolation, at locations both proximate and distant to the focus of invasion at multiple points in time. © 2016 by the Ecological Society of America.

  17. Deep South Atlantic carbonate chemistry and increased interocean deep water exchange during last deglaciation

    NASA Astrophysics Data System (ADS)

    Yu, Jimin; Anderson, Robert F.; Jin, Zhangdong; Menviel, Laurie; Zhang, Fei; Ryerson, Fredrick J.; Rohling, Eelco J.

    2014-04-01

    Carbon release from the deep ocean at glacial terminations is a critical component of past climate change, but the underlying mechanisms remain poorly understood. We present a 28,000-year high-resolution record of carbonate ion concentration, a key parameter of the global carbon cycle, at 5-km water depth in the South Atlantic. We observe similar carbonate ion concentrations between the Last Glacial Maximum and the late Holocene, despite elevated concentrations in the glacial surface ocean. This strongly supports the importance of respiratory carbon accumulation in a stratified deep ocean for atmospheric CO2 reduction during the last ice age. After ˜9 μmol/kg decline during Heinrich Stadial 1, deep South Atlantic carbonate ion concentration rose by ˜24 μmol/kg from the onset of Bølling to Pre-boreal, likely caused by strengthening North Atlantic Deep Water formation (Bølling) or increased ventilation in the Southern Ocean (Younger Drays) or both (Pre-boreal). The ˜15 μmol/kg decline in deep water carbonate ion since ˜10 ka is consistent with extraction of alkalinity from seawater by deep-sea CaCO3 compensation and coral reef growth on continental shelves during the Holocene. Between 16,600 and 15,000 years ago, deep South Atlantic carbonate ion values converged with those at 3.4-km water depth in the western equatorial Pacific, as did carbon isotope and radiocarbon values. These observations suggest a period of enhanced lateral exchange of carbon between the deep South Atlantic and Pacific Oceans, probably due to an increased transfer of momentum from southern westerlies to the Southern Ocean. By spreading carbon-rich deep Pacific waters around Antarctica for upwelling, invigorated interocean deep water exchange would lead to more efficient CO2 degassing from the Southern Ocean, and thus to an atmospheric CO2 rise, during the early deglaciation.

  18. DeepQA: improving the estimation of single protein model quality with deep belief networks.

    PubMed

    Cao, Renzhi; Bhattacharya, Debswapna; Hou, Jie; Cheng, Jianlin

    2016-12-05

    Protein quality assessment (QA) useful for ranking and selecting protein models has long been viewed as one of the major challenges for protein tertiary structure prediction. Especially, estimating the quality of a single protein model, which is important for selecting a few good models out of a large model pool consisting of mostly low-quality models, is still a largely unsolved problem. We introduce a novel single-model quality assessment method DeepQA based on deep belief network that utilizes a number of selected features describing the quality of a model from different perspectives, such as energy, physio-chemical characteristics, and structural information. The deep belief network is trained on several large datasets consisting of models from the Critical Assessment of Protein Structure Prediction (CASP) experiments, several publicly available datasets, and models generated by our in-house ab initio method. Our experiments demonstrate that deep belief network has better performance compared to Support Vector Machines and Neural Networks on the protein model quality assessment problem, and our method DeepQA achieves the state-of-the-art performance on CASP11 dataset. It also outperformed two well-established methods in selecting good outlier models from a large set of models of mostly low quality generated by ab initio modeling methods. DeepQA is a useful deep learning tool for protein single model quality assessment and protein structure prediction. The source code, executable, document and training/test datasets of DeepQA for Linux is freely available to non-commercial users at http://cactus.rnet.missouri.edu/DeepQA/ .

  19. Enhanced phosphorus reduction in simulated eutrophic water: a comparative study of submerged macrophytes, sediment microbial fuel cells, and their combination.

    PubMed

    Xu, Peng; Xiao, Enrong; Xu, Dan; Li, Juan; Zhang, Yi; Dai, Zhigang; Zhou, Qiaohong; Wu, Zhenbin

    2018-05-01

    The phosphorus reduction in water column was attempted by integrating sediment microbial fuel cells (SMFCs) with the submerged macrophyte Vallisneria spiralis. A comparative study was conducted to treat simulated water rich in phosphate with a control and three treatments: SMFC alone (SMFC), submerged macrophytes alone (macophyte), and combined macrophytes and fuel cells (M-SMFC). All treatments promoted phosphorus flux from the water column to sediments. Maximum phosphorus reduction was obtained in proportion to the highest stable phosphorus level in sediments in M-SMFC. For the initial phosphate concentrations of 0.2, 1, 2, and 4 mg/L, average phosphate values in the overlying water during four phases decreased by 33.3% (25.0%, 8.3%), 30.8% (5.1%, 17.9%), 36.5% (27.8%, 15.7%), and 36.2% (0.7%, 22.1%) for M-SMFC (macrophyte, SMFC), compared with the control. With macrophyte treatment, the obvious phosphorus release from sediments was observed during the declining period. However, such phenomenon was significantly inhibited with M-SMFC. The electrogenesis bacteria achieved stronger phosphorus adsorption and assimilation was significantly enriched on the closed-circuit anodes. The higher abundance of Geobacter and Pseudomonas in M-SMFC might in part explain the highest phosphorus reduction in the water column. M-SMFC treatment could be promising to control the phosphorus in eutrophic water bodies.

  20. Characterization of dissolved organic matter in a submerged membrane bioreactor by using three-dimensional excitation and emission matrix fluorescence spectroscopy.

    PubMed

    Wang, Zhiwei; Wu, Zhichao; Tang, Shujuan

    2009-04-01

    Three-dimensional excitation-emission matrix (EEM) fluorescence spectroscopy was employed to characterize dissolved organic matter (DOM) in a submerged membrane bioreactor (MBR). Three fluorescence peaks could be identified from the EEM fluorescence spectra of the DOM samples in the MBR. Two peaks were associated with the protein-like fluorophores, and the third was related to the visible humic acid-like fluorophores. Only two main peaks were observed in the EEM fluorescence spectra of the extracellular polymeric substance (EPS) samples, which were due to the fluorescence of protein-like and humic acid-like matters, respectively. However, the EEM fluorescence spectra of membrane foulants were observed to have three peaks. It was also found that the dominant fluorescence substances in membrane foulants were protein-like substances, which might be due to the retention of proteins in the DOM and/or EPS in the MBR by the fine pores of the membrane. Quantitative analysis of the fluorescence spectra including peak locations, fluorescence intensity, and different peak intensity ratios and the fluorescence regional integration (FRI) analysis were also carried out in order to better understand the similarities and differences among the EEM spectra of the DOM, EPS, and membrane foulant samples and to further provide an insight into membrane fouling caused by the fluorescence substances in the DOM in submerged MBRs.